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1

Flagle, Andrew Loren. "A national study of institutional policies for the evaluation of transfer applicants." Diss., Connect to online resource - MSU authorized users, 2008.

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Thesis (Ph.D.)--Michigan State University. Dept. of Higher, Adult, and Lifelong Education, 2008.
Title from PDF t.p. (viewed on Apr. 1, 2009) Includes bibliographical references (p.197-212). Also issued in print.
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2

Niu, Yuanlu. "How facial attractiveness of Chinese female applicants affects the decisions regarding a hypothetical employment evaluation." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/dissertations/1562.

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The purpose of this study was to explore how facial attractiveness of female job applicants influences the decision-making regarding a hypothetical employment evaluation in China. The study examined the effects of raters’ gender, job applicants’ facial attractiveness, and job applicants’ professional qualifications (education attainment and the years of work experience) on the interview selection, hiring, and salary decisions in a hypothetical situation. To examine the research hypotheses, a laboratory or “controlled” experiment was conducted in this quantitative study. There were two stages in this study. In Stage I, participants were recruited to rate 20 female facial photos, and based on the rating, the researcher selected two attractive photos and two unattractive photos to use in Stage II. In Stage II, college students of Human Resource Management (HRM) were recruited to evaluate six female job applications for an administrative assistant position in a hypothetical situation. Each application included one resume (high professional qualification or low professional qualification) and a photo indicator (an attractive photo, unattractive photo or no photo). Both Stage I and Stage II were within-subjects designs, also known as “repeated measures” designs. The study concluded that lookism or attractiveness bias existed in the hypothetical employment evaluations for the female applicants. Attaching an attractive photo on the resume was a benefit for the female applicants applying for the administration assistant position. Both male and female raters were more likely to interview, hire, and offer a higher salary to applicants with an attractive photo than the ones with an unattractive photo or without a photo in all of the hypothetical situations. However, male raters were more sensitive to the physical attractiveness of applicants than the female raters. Therefore, the issues of lookism or attractiveness bias in the workplace should be addressed. The author suggested that an application system should be designed and implemented which could prevent lookism at the early stages of the hiring process. Also, clarifying the definition of physical appearance discrimination and establishing legislation specific to physical appearance discrimination would be helpful to reduce the issues of lookism. Diversity training should be provided to employers and employees in the workplace to increase awareness of employment lookism. In future studies, the actual human resource (HR) professionals could be included to explore the effect of facial attractiveness on their employment decisions in the actual workplaces across different occupations and different cultures. In addition, future research could include several potential variables to control for a potentially significant aspect, such as rater’s attractiveness, rater’s age, years of rater in their professional field, or applicant’s gender.
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3

Bowman, Jeffry Stephen. "The Relationship Between Applicant Age and Evaluator Age in Pre-Interview Screening of Teacher Applicants." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1364296161.

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4

Stoddard, Jil A. "An evaluation of the impact of the Virginia employment commission's applicant screening procedure on the job service applicant." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/94473.

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The Virginia Employment Commission's Job Service has implemented an automated testing procedure to refer applicants to job openings. This procedure, Validity Generalization (VG) testing, utilizes the General Aptitude Test Battery (GATB) to assess and predict ability for successful performance in all occupations. The purpose of this study was to assess applicants' reactions to VG testing and to evaluate VG' s impact on applicants' subsequent placement outcomes. Twelve research questions were developed to examine applicants' attitudes toward 1) the GATB's useful-ness as an ability test and referral tool, 2) the services provided by the Job Service, and 3) their job. Overall findings revealed certain important trends. First, although initial reactions to VG were favorable, applicants' attitudes twelve weeks later were much less favorable, indicating dissatisfaction with the outcome of Job Service placement eff0rts. Only 7% of applicants tested were placed through VG referral. Second, findings indicated that VG testing produced no significant negative impact on applicant subgroups, such as minorities, females, Veterans, etc., relative to other applicants. Finally, results suggested that applicants placed through VG referral were no more satisfied with those jobs, perceived them to be no better person/job 'matches', and were no less likely to turnover than applicants placed through other means. Due to insufficient sample sizes for many analyses, the reliability of certain findings is uncertain. It was recommended that the VEC increase the number of applicant referrals made through VG, ensure that computer-maintained records are accurate and accessible and that Job Service personnel more-stringently follow the 'top-down' rank-ordered referral procedures which optimize the effectiveness of VG testing.
M.S.
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5

BUSCICCHIO, GIULIA. "Il Gender Bias nella Valutazione delle Lettere Motivazionali: Il Ruolo della Stereotipicità di Genere, della Struttura Argomentativa e delle Caratteristiche del Linguaggio." Doctoral thesis, Università Cattolica del Sacro Cuore, 2021. http://hdl.handle.net/10280/107359.

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Per esaminare quali fattori interagiscono nel causare una diversa percentuale di donne e uomini in alcuni settori lavorativi, mi sono concentrata sugli effetti della manipolazione del linguaggio di tratti e debolezze che descrivono candidati stereotipici o controstereotipici sulla valutazione finale dei candidati. A tal fine, ho condotto tre studi pilota e tre studi principali. Questi effetti sono stati testati considerando anche l'effetto del processo cognitivo dei partecipanti e delle caratteristiche interne (es. bias di genere, attitudini verso le donne, comunion e agency dei partecipanti), che sono stati integrati in un nuovo path model che è stato testato nei tre studi. I risultati hanno mostrato che la manipolazione del linguaggio in cui sono state presentate le informazioni sui tratti e sulle debolezze ha aiutato solo i candidati donna a migliorare la propria valutazione: le donne controstereotipiche descritte concretamente, così come le donne stereotipiche descritte in modo astratto hanno ottenuto un giudizio più favorevole rispetto agli uomini. Il path model ha rivelato che l'onestà percepita dei candidati svolge un ruolo mediatore nella relazione delle caratteristiche interne dei partecipanti e la valutazione dei candidati.
To examine which factors act together in causing unbalanced percentage of women and men in different job sectors, I focused on the effects of the manipulation of the language in which stereotypical or counterstereotypical applicants’ traits and weaknesses are presented on the evaluation of female and male target applicants. To this end, I conducted three pilot studies and three studies. These effects were tested while considering also the effect of participants’ cognitive process and internal characteristics (e.g., gender bias, attitudes toward women, self-reported communion, and agency), which were integrated into a new path model that was performed along with the three studies. Results showed that manipulating language in which information on traits and weaknesses was presented helped only female applicants to increase their evaluation: Counterstereotypical women concretely described, as well as stereotypical women abstractly described gain more positive evaluation than men. The final path model revealed the perceived honesty of applicants plays the mediating role in the relation of some participants’ internal characteristics with the evaluation of applicants. Theoretical and practical implication have been discussed.
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6

Hunter, Seft. "The relationship of interviewer's communication behaviors and applicant's evaluation of the interviewer." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1914.

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7

Sink, David William 1947. "The Impact of Applicant Disability on Personnel Managers' Evaluative Judgments." Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/72899.

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This study was the investigation of the effects of five factors related to hiring handicapped individuals. The five factors were psychological disability, physical disability, no disability, and a good or poor work record. The purpose of the study was to determine whether a relationship existed between perceived employment decisions and (a) applicant disability; (b) applicant work record; and (c) personnel managers' demographic characteristics.
The population from which the sample was drawn consisted of personnel managers in personnel associations and educational administrators in the piedmont and eastern sections of North Carolina in June and July of 1983. The sample for the study consisted of 133 persons, stratified by size of company or institution.
The personnel managers were randomly assigned to one of six experimental conditions in a 2 x 3 (levels of disability x levels of work record) factorial design. Each subject reviewed staged information on the job applicant prior to listening to a taped job interview of the applicant. After hearing the interview, managers rated the quality of the interview, using the Job Interview Rating Scale and stated the probability that they would hire the applicant on the Probability Of Hire Score. Factors affecting personnel managers' decisions to hire the handicapped were identified through a personnel managers' questionnaire.
Higher ratings of the job interview and higher probability of hiring occurred when a positive work record was present. Applicants were less likely to be hired if they had a psychological disability. Ratings of job interviews were not affected by disability levels. There were no interactions between work records and disability status. "Ability to perform job" and "productivity" were ranked by the managers as the most influential among the 26 factors considered by personnel managers when making decisions to hire the handicapped. None of the demographic variables of personnel managers of age, sex, education and experience were significant in their relationship to hiring. Sex of the interviewer appeared to be the best predictor of interview rating.
Ed. D.
Vita.
Abstract.
Bibliography: leaves 94-106.
This dissertation may contain sensitive information and is therefore not available online.
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8

Moore, Jason S. "THE EFFECTS OF DIVERSITY INITIATIVES ON THE DISTORTION OF APPLICANT QUALIFICATIONS AND DECISION STANDARDS." Bowling Green State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1162227465.

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9

Kaiser, Sally Allene. "Job applicants' age, gender, and exercise lifestyle as determinants of evaluations of hiring application forms." CSUSB ScholarWorks, 1993. https://scholarworks.lib.csusb.edu/etd-project/696.

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10

Taylor, Mary Anne. "The effects of rater sex, ratee sex, and applicant attire on personnel selection." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/101466.

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The impact of attire on assessments of job applicants was investigated by creating three dress conditions for two male and two female rates. A formal, intermediate, and casual condition were portrayed for each of the four stimuli. Stimuli were rated on six dimensions relevant to performance as a retail department store manager in a between-subjects design. Results indicate that the role of attire in estimates of performance depends on the sex of the rater and the sex of the ratee. Dissimilar ratings were obtained from males and females who assessed individuals in a particular dress condition. These results indicated that the hypothesized main effects for dress and rater sex were overly simplistic. The implication of this finding for future research is discussed. Findings also suggested the importance of including a reasonable range and portrayal of attire in studies of this type. The inclusion of an intermediate apparel condition showed that raters prefer this attire over formal wear under certain rating conditions. The importance of this finding for future attire research designs is discussed.
M.S.
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11

Reis, Susan Bon. "Effects of sex of evaluator, applicant, and reference source on screening decisions for an administrative position /." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487940308432387.

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12

Reis, Simone Maria de ávila Silva. "Avaliação comparativa do desempenho de alunos admitidos na Faculdade de Odontologia da Universidade Federal de Uberlândia - FOUFU - via Vestibular e via PAIES, no período de 2000/1 a 2003/2." Universidade Federal de Uberlândia, 2006. https://repositorio.ufu.br/handle/123456789/16991.

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The research approached the selective process used by the Brazilian Colleges in the admission of candidates to the higher education. The raising demand for vacancies in the public universities contributed to the exceeding competition in the college entrance exams, what rebounded in the way of high school conduction, that has acquired propaedeutic characteristics. The negative reflection about the objectives of this level of the teaching trigged off searches for the alternatives selective process, that could rescue and encourage the realization of the purposes originally offered to the high school. New proposals acquired impulse with the promulgation of the Lei de Diretrizes e Bases da Educação Nacional (LDB) nº 9394, in 12/20/1996, that extinguished the traditional college entrance exams exclusiveness as the selection s way. The Universidade Federal de Uberlândia implanted the Alternative Process to College Entrance PAIES, a process of evaluation in series, with exams aplicated in the end of the three series of high school. The candidates that reach the best general results in the three evaluations, since 1997, are selected to occupy 25% of the offered vacancies, yearly, by the higher courses of UFU; entering always in the first semester. While the traditional college entrance exams selects for the others 75% of the offered vacancies; that enter in both semesters. The aim of this work was to know the factor of predictive validate of these two selective processes, through the comparison of the academic performance of the student s groups of the Faculdade de Odontologia da Universidade Federal de Uberlândia (FOUFU) admitted by traditional college entrance exams and by Alternative Process to College Entrance (PAIES). The subjects of the research were the students of the 51º to 56º groups of the Odontology Course, examined in pre established periods of the course, by analysis of the official registers of notes and subjective evaluation of the students and the teachers, by the application of the questionnaire. The data, collected between 2002/2 and 2003/2, were treated statistically and analyzed qualitatively and quantitatively. The results allowed to conclude that the admitted students by Alternative Process to College Entrance (PAIES) presented best academic performance and best competence of learning during the graduation, and suggested that this selective process present level of factor of predictive validate higher then the traditional college entrance exams.
A pesquisa abordou os processos seletivos utilizados pelas Instituições de Ensino Superior (IES) brasileiras na admissão de candidatos aos cursos de graduação. A crescente demanda por vagas nas Universidades Públicas contribuiu para a excessiva concorrência nos exames vestibulares, o que repercutiu na forma de condução do Ensino Médio, que assumiu funções meramente propedêuticas. Os reflexos negativos sobre os objetivos deste nível de ensino desencadearam buscas por processos seletivos alternativos, que pudessem resgatar e fomentar a concretização das metas originalmente propostas para o Ensino Secundário. Com a promulgação da Lei de Diretrizes e Bases da Educação Nacional nº 9394, em 20/12/1996, que extinguiu a exclusividade do vestibular como meio de seleção para o ingresso no Ensino Superior, novas propostas de processos seletivos têm sido implantadas e utilizadas pelas Instituições de Ensino. A Universidade Federal de Uberlândia (UFU) implantou o Programa Alternativo de Ingresso ao Ensino Superior (PAIES), processo de avaliação seriada com provas aplicadas ao final das três séries do Ensino Médio. Os candidatos que alcançam os melhores resultados gerais nas três avaliações, desde 1997, são selecionados para ocupar 25% das vagas oferecidas, anualmente, pelos cursos superiores da UFU, ingressando sempre no primeiro semestre. Por sua vez, o Processo Seletivo Semestral (VESTIBULAR) seleciona os candidatos para os demais 75% das vagas, que ingressam em ambos os semestres. O objetivo deste trabalho foi determinar o Fator de Validade Preditiva1 desses dois processos seletivos, mediante a avaliação comparativa do desempenho acadêmico dos grupos de alunos da Faculdade de Odontologia da UFU admitidos via VESTIBULAR e via PAIES. Os sujeitos da pesquisa foram os alunos das 51ª à 56ª turmas, investigados em períodos pré-estabelecidos do curso, mediante análise dos registros oficiais de notas e avaliações subjetivas docente e discente, via questionários. Os dados, coletados entre 2002/2 e 2003/2, foram analisados de forma qualitativa e quantitativa, e tratados estatisticamente. Os resultados permitiram concluir que os alunos ingressos via PAIES apresentaram melhor performance e maior competência de aprendizagem durante a graduação, e demonstraram que o Fator de Validade Preditiva do PAIES é superior ao do VESTIBULAR.
Mestre em Odontologia
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13

White, Tiffany N. "Two Steps Forward, One Step Back: Effects of Skin Tone and Cross-Platform Self-Presentation on Evaluations of Black Job Applicants." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500574106470159.

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14

Wise, Shelby. "An Evaluation of Test-Taking Performance in a Selection Context Through Motivational Mechanisms and Job-Relatedness Perceptions." Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1509628823852464.

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15

Chen, Liubeite <1991&gt. "Evaluation of soccer players in Serie A: a data-driven approach." Master's Degree Thesis, Università Ca' Foscari Venezia, 2021. http://hdl.handle.net/10579/20141.

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Thanks to the technological innovation of electronic motion recording methods, the use of quantitative data in sport to measure performance has increased significantly in recent years, enough to represent a new specialty of statistical studies. The most relevant literature concerning quantitative models for evaluating the price of a football player is examined. Through OLS, an empirical analysis is conducted that can understand and predict what are the performance variables that can determine a player's trading price. The data relate to the exchanges that took place in the top Italian football championship (Serie A) between 2017 and 2019. The variables that determine the price change due to the role, therefore there is a strong specialization by role. The performance does not fully explain the price changes of the players. Furthermore, the higher investments are not necessarily proportional to the sporting results of the team.
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Ghezzo, Alessandro <1962&gt. "The biological basis of autism spectrum disorders: evaluation of oxidative stress and erytrocyte membrane alterations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7116/1/Ghezzo_Alessandro_tesi.pdf.

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This case-control study involved a total of 29 autistic children (Au) aged 6 to 12 years, and 28 gender and age-matched typically developing children (TD). We evaluated a high number of peripheral oxidative stress parameters, erythrocyte and lymphocyte membrane functional features and membrane lipid composition of erythrocyte. Erythrocyte TBARS, Peroxiredoxin II, Protein Carbonyl Groups and urinary HEL and isoprostane levels were elevated in AU (confirming an imbalance of the redox status of Au); other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma Total antioxidant capacity and plasma carbonyl groups, erythrocyte SOD and catalase activities) were unchanged, whilst peroxiredoxin I showed a trend of elevated levels in red blood cells of Au children. A very significant reduction of both erythrocyte and lymphocyte Na+, K+-ATPase activity (NKA), a reduction of erythrocyte membrane fluidity, a reduction of phospatydyl serine exposition on erythrocyte membranes, an alteration in erythrocyte fatty acid membrane profile (increase in MUFA and in ω6/ω3 ratio due to decrease in EPA and DHA) and a reduction of cholesterol content of erythrocyte membrane were found in Au compared to TD, without change in erythrocyte membrane sialic acid content and in lymphocyte membrane fluidity. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity, and ADOS and CARS score are inversely related to peroxiredoxin II levels. Oxidative stress and erythrocyte structural and functional alterations may play a role in the pathogenesis of Autism Spectrum Disorders and could be potentially utilized as peripheral biomarkers.
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17

Ghezzo, Alessandro <1962&gt. "The biological basis of autism spectrum disorders: evaluation of oxidative stress and erytrocyte membrane alterations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7116/.

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This case-control study involved a total of 29 autistic children (Au) aged 6 to 12 years, and 28 gender and age-matched typically developing children (TD). We evaluated a high number of peripheral oxidative stress parameters, erythrocyte and lymphocyte membrane functional features and membrane lipid composition of erythrocyte. Erythrocyte TBARS, Peroxiredoxin II, Protein Carbonyl Groups and urinary HEL and isoprostane levels were elevated in AU (confirming an imbalance of the redox status of Au); other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma Total antioxidant capacity and plasma carbonyl groups, erythrocyte SOD and catalase activities) were unchanged, whilst peroxiredoxin I showed a trend of elevated levels in red blood cells of Au children. A very significant reduction of both erythrocyte and lymphocyte Na+, K+-ATPase activity (NKA), a reduction of erythrocyte membrane fluidity, a reduction of phospatydyl serine exposition on erythrocyte membranes, an alteration in erythrocyte fatty acid membrane profile (increase in MUFA and in ω6/ω3 ratio due to decrease in EPA and DHA) and a reduction of cholesterol content of erythrocyte membrane were found in Au compared to TD, without change in erythrocyte membrane sialic acid content and in lymphocyte membrane fluidity. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity, and ADOS and CARS score are inversely related to peroxiredoxin II levels. Oxidative stress and erythrocyte structural and functional alterations may play a role in the pathogenesis of Autism Spectrum Disorders and could be potentially utilized as peripheral biomarkers.
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18

PASTORINO, GIULIA. "Evaluation of fodder legumes for nutraceutical, pharmaceutical and cosmetic applications." Doctoral thesis, Università degli studi di Genova, 2018. http://hdl.handle.net/11567/932126.

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Since the beginning of human cultivation, the role of plants in medicine has been of huge importance. The aim of this PhD Project is to investigate some forage plants belonging to the family of Fabaceae to gain knowledge concerning their possible use in nutraceutical, pharmaceutical and cosmetics field. These plants have been chosen because they are characterized by great productive potential, but they are still under-exploited from the officinal and industrial point of view. They are also a potential source for the extraction of bioactive compounds with possible pharmaceutical and cosmetic applications (Rodrigues et al., 2013;Cornara et al., 2016), being generally rich in secondary metabolites such as alkaloids, amines, flavonoids, coumarins, condensed tannins and saponins (Burlando et al., 2010; Pastorino et al., 2017) To increase their use also in the industrial sector and, consequently, their commercial value, the study has focused on the identification of bioactive compounds with possible interest in human health. In this study a multidisciplinary approach was carried out, investigating several aspects such as antioxidant, antilipidemic and cytotoxicity strength, content of total phenols and flavonoids. In this PhD Project we studied four species of legumes: Melilotus officinalis (L.) Pall., Lespedeza capitata Michx., Sulla coronaria (L.) Medik and Glycyrrhiza glabra L. Thanks to a collaboration with Egadi S.r.l., Favignana, Italy, we also concentrated our study to another kind of plant, belonging to the family of Potamogetonaceae: Posidonia oceanica (L.) Delile. The species has shown bioactivities suitable for the development of cosmetic and dermatologic applications. In summary, the results of these investigations show new opportunities to exploit the plants studied plants in bioindustry processes, possibly increasing their commercial value.
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Rivetti, Di Val Cervo Stefano <1975&gt. "Performance evaluation of detectors for digital radiography." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3611/1/stefano_rivetti_tesi.pdf.

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To date the hospital radiological workflow is completing a transition from analog to digital technology. Since the X-rays digital detection technologies have become mature, hospitals are trading on the natural devices turnover to replace the conventional screen film devices with digital ones. The transition process is complex and involves not just the equipment replacement but also new arrangements for image transmission, display (and reporting) and storage. This work is focused on 2D digital detector’s characterization with a concern to specific clinical application; the systems features linked to the image quality are analyzed to assess the clinical performances, the conversion efficiency, and the minimum dose necessary to get an acceptable image. The first section overviews the digital detector technologies focusing on the recent and promising technological developments. The second section contains a description of the characterization methods considered in this thesis categorized in physical, psychophysical and clinical; theory, models and procedures are described as well. The third section contains a set of characterizations performed on new equipments that appears to be some of the most advanced technologies available to date. The fourth section deals with some procedures and schemes employed for quality assurance programs.
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Rivetti, Di Val Cervo Stefano <1975&gt. "Performance evaluation of detectors for digital radiography." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3611/.

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To date the hospital radiological workflow is completing a transition from analog to digital technology. Since the X-rays digital detection technologies have become mature, hospitals are trading on the natural devices turnover to replace the conventional screen film devices with digital ones. The transition process is complex and involves not just the equipment replacement but also new arrangements for image transmission, display (and reporting) and storage. This work is focused on 2D digital detector’s characterization with a concern to specific clinical application; the systems features linked to the image quality are analyzed to assess the clinical performances, the conversion efficiency, and the minimum dose necessary to get an acceptable image. The first section overviews the digital detector technologies focusing on the recent and promising technological developments. The second section contains a description of the characterization methods considered in this thesis categorized in physical, psychophysical and clinical; theory, models and procedures are described as well. The third section contains a set of characterizations performed on new equipments that appears to be some of the most advanced technologies available to date. The fourth section deals with some procedures and schemes employed for quality assurance programs.
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21

Colais, Paola <1975&gt. "Validity of Robson Ten Group Classification System for comparative evaluation of caesarean section." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1688/1/Colais_Paola_tesi.pdf.

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Colais, Paola <1975&gt. "Validity of Robson Ten Group Classification System for comparative evaluation of caesarean section." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1688/.

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23

Forlani, Margherita <1986&gt. "A New Test Rig for In-Vitro Evaluation of the Knee Joint Behaviour." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7137/1/Forlani_Margherita_Tesi.pdf.

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The evaluation of the knee joint behavior is fundamental in many applications, such as joint modeling, prosthesis and orthosis design. In-vitro tests are important in order to analyse knee behavior when simulating various loading conditions and studying physiology of the joint. A new test rig for in-vitro evaluation of the knee joint behavior is presented in this paper. It represents the evolution of a previously proposed rig, designed to overcome its principal limitations and to improve its performances. The design procedure and the adopted solution in order to satisfy the specifications are presented here. Thanks to its 6-6 Gough-Stewart parallel manipulator loading system, the rig replicates general loading conditions, like daily actions or clinical tests, on the specimen in a wide range of flexion angles. The restraining actions of knee muscles can be simulated when active actions are simulated. The joint motion in response to the applied loads, guided by passive articular structures and muscles, is permitted by the characteristics of the loading system which is force controlled. The new test rig guarantees visibility so that motion can be measured by an optoelectronic system. Furthermore, the control system of the new test rig allows the estimation of the contribution of the principal leg muscles in guaranteeing the equilibrium of the joint by the system for muscle simulation. Accuracy in positioning is guaranteed by the designed tibia and femur fixation systems,which allow unmounting and remounting the specimen in the same pose. The test rig presented in this paper permits the analysis of the behavior of the knee joint and comparative analysis on the same specimen before and after surgery, in a way to assess the goodness of prostheses or surgical treatments.
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Forlani, Margherita <1986&gt. "A New Test Rig for In-Vitro Evaluation of the Knee Joint Behaviour." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7137/.

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The evaluation of the knee joint behavior is fundamental in many applications, such as joint modeling, prosthesis and orthosis design. In-vitro tests are important in order to analyse knee behavior when simulating various loading conditions and studying physiology of the joint. A new test rig for in-vitro evaluation of the knee joint behavior is presented in this paper. It represents the evolution of a previously proposed rig, designed to overcome its principal limitations and to improve its performances. The design procedure and the adopted solution in order to satisfy the specifications are presented here. Thanks to its 6-6 Gough-Stewart parallel manipulator loading system, the rig replicates general loading conditions, like daily actions or clinical tests, on the specimen in a wide range of flexion angles. The restraining actions of knee muscles can be simulated when active actions are simulated. The joint motion in response to the applied loads, guided by passive articular structures and muscles, is permitted by the characteristics of the loading system which is force controlled. The new test rig guarantees visibility so that motion can be measured by an optoelectronic system. Furthermore, the control system of the new test rig allows the estimation of the contribution of the principal leg muscles in guaranteeing the equilibrium of the joint by the system for muscle simulation. Accuracy in positioning is guaranteed by the designed tibia and femur fixation systems,which allow unmounting and remounting the specimen in the same pose. The test rig presented in this paper permits the analysis of the behavior of the knee joint and comparative analysis on the same specimen before and after surgery, in a way to assess the goodness of prostheses or surgical treatments.
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Lanzoni, Alberto <1965&gt. "Evaluation of the Effects of BT-Maize on Non-Target Insects Using a Demographic Approach." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7536/1/LanzoniAlberto.pdf.

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An experiment on life-table of the aphid on Bt-maize and isoline was performed. No significant differences were found between treatments. Differences in aphid performance were the lower adult and total longevity on the second generation, and the opposite trend of the pre-reproductive time that increased from the first to the second generation on isoline and decreased on Bt-maize. None of the demographic parameters analyzed showed significant differences. LTREs showed that this trend could be ascribed to a higher fecundity of young adult aphids of the second generation, probably connected to the lower pre-reproductive time. These differences could be the result of differences in chemical constituents. Analyses of secondary metabolites showed significant reduction of free polyphenols in Bt-maize. The experiment with the coccinellid H. variegata were performed evaluating the effects due to eating Cry1Ab toxin in maize pollen. No significant differences were found between GM and near-isogenic maize in all the parameter studied. Even if no significant, the reduced λ of H. variegata feeding on Bt-maize pollen, caused a population delay of 28 days. LTRE decomposition showed a lower egg and larval survival in the offspring of Bt pollen fed H. variegata, all contributing most on λ reduction. A bioassays were carried out in the greenhouse to assess the population-level responses of the coccinellid H. variegata, feeding on aphids reared on Bt-Maize and near-isogenic plants in a more realistic condition respect to laboratory trials. No differences in the mean number of eggs, larvae, pupae, and adults of H. variegata between Bt-maize and near-isogenic line. A higher number of pupae was found a week early in Bt-maize. No differences observed in H. variegata population growth rates between treatments. Using LTRE decomposition, the effect of Bt-maize exposition on λ have been decomposed into contributions arising from the effect on each stage-specific parameter.
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26

Lanzoni, Alberto <1965&gt. "Evaluation of the Effects of BT-Maize on Non-Target Insects Using a Demographic Approach." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7536/.

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An experiment on life-table of the aphid on Bt-maize and isoline was performed. No significant differences were found between treatments. Differences in aphid performance were the lower adult and total longevity on the second generation, and the opposite trend of the pre-reproductive time that increased from the first to the second generation on isoline and decreased on Bt-maize. None of the demographic parameters analyzed showed significant differences. LTREs showed that this trend could be ascribed to a higher fecundity of young adult aphids of the second generation, probably connected to the lower pre-reproductive time. These differences could be the result of differences in chemical constituents. Analyses of secondary metabolites showed significant reduction of free polyphenols in Bt-maize. The experiment with the coccinellid H. variegata were performed evaluating the effects due to eating Cry1Ab toxin in maize pollen. No significant differences were found between GM and near-isogenic maize in all the parameter studied. Even if no significant, the reduced λ of H. variegata feeding on Bt-maize pollen, caused a population delay of 28 days. LTRE decomposition showed a lower egg and larval survival in the offspring of Bt pollen fed H. variegata, all contributing most on λ reduction. A bioassays were carried out in the greenhouse to assess the population-level responses of the coccinellid H. variegata, feeding on aphids reared on Bt-Maize and near-isogenic plants in a more realistic condition respect to laboratory trials. No differences in the mean number of eggs, larvae, pupae, and adults of H. variegata between Bt-maize and near-isogenic line. A higher number of pupae was found a week early in Bt-maize. No differences observed in H. variegata population growth rates between treatments. Using LTRE decomposition, the effect of Bt-maize exposition on λ have been decomposed into contributions arising from the effect on each stage-specific parameter.
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27

Pacifico, Daniele <1982&gt. "Tax-benefit microsimulation models for the evaluation of public policies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2587/1/Pacifico_Daniele_tesi.pdf.

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28

Pacifico, Daniele <1982&gt. "Tax-benefit microsimulation models for the evaluation of public policies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2587/.

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29

MADDALENA, GIUSEPPE. "Identification and evaluation of attractiveness of lactic acid bacteria as a bait for Drosophila suzukii Matsumura." Doctoral thesis, Università degli studi del Molise, 2016. http://hdl.handle.net/11695/66264.

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Il rapido incremento delle attività commerciali, il perpetuarsi delle migrazioni umane, il turismo, i trasporti e i viaggi sempre più celeri, nel corso dell’ultimo secolo hanno notevolmente favorito la diffusione di numerose specie invasive, che hanno superato barriere geografiche, anche considerevoli, in un ristretto arco temporale. Questa tendenza è destinata ad aumentare ulteriormente, e le specie invasive provenienti da altri Paesi, prima sconosciute, sono da annoverare tre le principali minacce per la biodiversità e la produzione alimentare in tutto il mondo. Gli insetti rappresentano la maggioranza degli organismi viventi e, quindi, costituiscono larga parte del problema delle specie invasive, tanto che in molte aree, come Nord America, Australia, Asia e Sud Africa, gli insetti dannosi alloctoni sono considerati importanti quanto, e forse più, di quelli autoctoni. Tradizionalmente l’Europa ha subito danni meno ingenti da parte di insetti di provenienza esterna, tendenza che è notevolmente cambiata in anni recenti e che ha portato ad un interesse sempre maggiore nei confronti degli insetti alieni che hanno colonizzato il territorio comunitario. Drosophila suzukii Matsumura (Diptera: Drosophilidae), nota anche come moscerino dei piccoli frutti o spotted-wing drosophila (SWD), originaria del sud-est asiatico, è un fitofago di recente introduzione in Europa, Stati Uniti e Canada, ove i danni sono stati rinvenuti su numerose colture come ciliegio, vite, uva spina, lampone e frutti di bosco in genere, pesco, susino, cachi, pomodoro, olivo, gelso e nespolo, di cui attacca i frutti. Gli adulti di D. suzukii sono moscerini lunghi 2-3 mm, con occhi rossi, torace marrone chiaro o giallastro e strisce nere sull'addome. Sono caratterizzati da uno spiccato dimorfismo sessuale; i maschi mostrano, infatti, una macchia scura al margine anteriore di ogni ala, le femmine un grande ovipositore seghettato. Le uova sono bianco latte, oblunghe (0,5-0,7 x 0,2 mm) e con due filamenti ad un’estremità; dell’uovo, deposto sotto l’epicarpo, sono visibili dall’esterno solo i due filamenti sporgenti (ca. 0,4 mm) dalla cicatrice di ovideposizione. Le larve si sviluppano attraverso tre età, sono di colore bianco traslucido e vivono all’interno del frutto ospite, nutrendosi della polpa e dei microrganismi naturalmente presenti, causandone il deterioramento; le cicatrici di ovideposizione, infatti, consentono l’ingresso di patogeni, come batteri e funghi, che comportano la cascola precoce dei frutti danneggiati. I danni economici causati da D. suzukii sono stati stimati in circa 2 miliardi di dollari in America, oltre 4 miliardi in Europa e 500 milioni in Asia. Appare scontato pensare che gli insetticidi di sintesi possano rappresentare il mezzo principale per il controllo e la gestione di D. suzukii ma, data la novità rappresentata da questo fitofago, deve essere individuata, intanto, una soglia economica di danno. Insetticidi di sintesi quali organofosfati, piretroidi e spinosad, hanno dimostrato una certa efficacia contro D. suzukii; l’altra faccia della medaglia mostra come questi principi attivi ad ampio spettro di azione siano tossici per gli insetti utili, oltre che essere responsabili dell’aumento dei residui presenti nei frutti, con tutti i rischi conseguenti per la salute umana. Risultati incoraggianti sono attesi dall’uso di agenti di biocontrollo come funghi, batteri, virus e altri nemici naturali del carpofago, ovvero predatori e parassitoidi, che potrebbero essere usati per limitarne le popolazioni. Il metodo attualmente più utilizzato per il monitoraggio di D. suzukii è basato sull’impiego di trappole costituite da un bicchiere di plastica forato contenente aceto di sidro di mele, un tensioattivo e un pannello adesivo di colore giallo. Tali trappole sono inefficaci per un monitoraggio precoce di D. suzukii, le cui popolazioni raggiungono rapidamente densità tali da arrecare danni, in quanto progettate per catturare altri insetti, in particolare Drosophilidae. Al fine di mettere a punto strategie efficaci di cattura massale, sono necessari attrattivi altamente efficaci e selettivi. Per D. suzukii, osservazioni preliminari confermano che l’insetto adulto è richiamato dalla frutta lesionata e preferibilmente in stato di fermentazione, come suggerisce la naturale attrazione esercitata da una varietà di liquidi fermentati, tra cui vino, aceto, succhi di frutta e derivati, nonché dall’associazione, recentemente riportata, di questo insetto con una comunità di diverse specie di lieviti, come Hanseniaspora uvarum (Niehaus) Shehata et al. Allo stato attuale, le trappole più efficaci per catturare D. suzukii sono innescate con diversi tipi di aceto e vino, substrati entrambi derivanti dalla fermentazione mediata sia da lieviti che da batteri. Una delle esche liquide commerciali, il cosiddetto “Droskidrink”, ha fornito risultati promettenti sia nel monitoraggio di D. suzukii, condotto negli anni 2011-2013 in provincia di Trento, che in prove preliminari di cattura massale. L’obiettivo principale di questo lavoro, pertanto, è stato quello di studiare alcuni aspetti poco noti di D. suzukii, in particolare quelli inerenti la percezione di stimoli di varia natura e il riconoscimento di substrati di interesse per la messa a punto di esche innovative e altamente efficaci da utilizzare nel monitoraggio e in strategie di controllo del carpofago. In particolare, gli studi sono stati indirizzati alla caratterizzazione di parametri biologici, fisici e chimici utili per valutare l’efficacia in campo dell’attrattivo noto come “Droskidrink”, l’esca commerciale raccomandata contro D. suzukii anche in pieno campo. Le prove di campo sono state condotte nella regione Trentino-Alto Adige, dove il fitofago ha recentemente causato danni ingenti. La ricerca ha sviluppato un nuovo tipo di esca, in cui l’attrattivo commerciale “Droskidrink” è risultato fortemente potenziato nella sua azione grazie all’associazione con microrganismi in grado di rilasciare sostanze volatili biologicamente attive su D. suzukii. Gli studi sono proseguiti presso l’Oregon State University, dove è stata saggiata la funzionalità della trappola innescata con il nuovo attrattivo anche in ambienti ecologicamente diversi, con l’intento di accelerare la ricerca e il trasferimento tecnologico di nuovi metodi ecosostenibili di controllo di D. suzukii basati, ad esempio, su tecniche di cattura massale. Nel presente lavoro è stato possibile dimostrare l’importanza dei microrganismi, in particolare batteri lattici, e più propriamente ceppi appartenenti alla specie Oenococcus oeni (Garvie) Dicks et al., nel miglioramento della capacità di cattura del “Droskidrink”, dovuto a sostanze prodotte durante la fermentazione malolattica. Gli studi compiuti hanno anche condotto alla messa a punto di un nuovo modello di trappola che sembra agire in modo sinergico con la miscela attrattiva utilizzata e che, tra l’altro, è in grado di ridurre i tempi necessari per la quantificazione e la determinazione degli individui catturati. Interessante è risultata la capacità di questo nuovo modello di trappola di catturare un consistente numero di individui, specialmente di sesso femminile, in periodi caratterizzati da temperature al limite della sopravvivenza di D. suzukii, ovvero in presenza di basse densità di popolazione del carpofago. Questi risultati permettono di ipotizzare una buona efficacia dell’applicazione precoce delle tecniche di cattura massale o di lotta attratticida, che potrebbero condurre, come auspicato, ad una significativa riduzione del numero di individui presenti in campo al momento della comparsa dei frutti adatti all’ovideposizione.
The spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), native of Eastern Asia, is an invasive alien species in Europe and the Americas and is one of the main emerging pests of valuable crops, including soft fruits and wine grapes. The conventional approach to handle infestations of SWD involves the use of commercially available insecticides, but these do not seem able to ensure effective results; consequently, alternative strategies are strongly required. Mass trapping uses a high density of traps baited with a lure and is one of the most promising methods studied and tested so far. Consequently, an improvement in the bait composition is obligatory to guarantee reliable attractivity to SWD. This study was aimed precisely to investigate and improve upon one of the best attractant mixtures for SWD, the “Droskidrink” (DD). The goal of the work was centred on the exploitation of lactic acid bacteria as a biological catalyst in the production of organic volatile molecules attractive to SWD, thanks to the fermentation of sugars and organic acids present in the liquid bait. Strains of lactic acid bacteria were chosen because they are usually involved in the fermentation of wine and vinegar, historically the most attractive liquids for species of Drosophilidae. A series of preliminary field tests was coupled with laboratory tests to describe the behaviour and performance of various kinds of lactic acid bacteria, in this particular application. Afterwards, we focused our analysis on different biotypes of the bacterium Oenococcus oeni (Garvie) Dicks et al. that revealed a high resistance to stressful environmental conditions of the liquid bait and, at the same time, a promising attractive capacity to SWD. Attention was then moved to a new model of trap able to produce a synergistic effect between the trap and the liquid bait. Our results showed that the attractiveness of DD was greatly increased by the addition of O. oeni to the standard mixture. Malolactic fermentation due to O. oeni released volatile substances attractive to SWD. In particular, the new trap-bait combination provided excellent results, increasing the number of catches, especially with regard to female individuals and particularly during the cold seasons, when SWD has low population density. In addition, this new trap design is simpler and faster to service, compared to the traps used previously. The long-term goal is to accelerate research and technology transfer toward the development of mass trapping and attract-and-kill strategies based on the use of traps baited with this new attractant. Moreover, through the development of a trap utilizing the best characteristics identified in this study, we were able to obtain excellent levels of catches during the whole year.
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BOLOGNINI, SARA. "Towards the evaluation of innovation procurement: The Pre-Commercial Procurement in Italy." Doctoral thesis, Università Politecnica delle Marche, 2021. http://hdl.handle.net/11566/291095.

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Negli ultimi due decenni, l'uso strategico degli appalti pubblici è diventato un tema sempre più centrale della politica europea dell'innovazione poiché può migliorare i servizi pubblici guidando il cambiamento tecnologico verso obiettivi socialmente condivisi. L'applicazione degli appalti pubblici in acquisti innovativi si basa su una triplice logica: (1) il miglioramento dei servizi pubblici; (2) l'incentivo delle aziende a essere più innovative; e (3) il perseguimento di obiettivi o missioni sociali più ampie. Il dibattito accademico ha affrontato, in diverse prospettive, il ruolo degli appalti pubblici come motore dell'innovazione. Dagli anni 90 ', diversi autori si sono interessati al ruolo degli appalti come strumento di politica dell'innovazione, hanno discusso degli appalti pubblici come uno degli elementi critici di una politica di innovazione orientata alla domanda e hanno sottolineato il ruolo dei policymakers nella promozione pratiche favorevoli all'innovazione in tutti i tipi di appalti. Nonostante la crescente consapevolezza che la domanda pubblica può stimolare l'innovazione, gli investimenti dedicati all'adozione di soluzioni innovative in Europa sono appena sopra la metà del livello atteso. uesta tesi affronta il tema degli appalti per l'innovazione concentrandosi sull'attuazione degli appalti Pre-commerciali (o Pre-Commercial Procurement-PCP), un approccio relativamente nuovo per l'approvvigionamento di servizi di ricerca e sviluppo, definito dalla Commissione Europea COM (2007) 799. La tesi considera i tre attori chiave coinvolti l'implementazione della politica di approvvigionamento di innovazione: il decisore politico, l'acquirente pubblico e il fornitore. Analizzando in parallelo (e in qualche modo anche congiuntamente) queste tre diverse prospettive sulle esperienze di appalto PCP, la dissertazione mira a valutare la politica degli appalti per l'innovazione nel quadro politico italiano. A questo proposito, la tesi si basa su tre studi originali: Studio 1- L'esperienza in italiano e nelle regioni italiane; Studio 2- Il punto di vista del procuratore; Studio 3-La prospettiva dei fornitori.L'approccio metodologico per l'intero lavoro si basa sul "Monitoraggio, valutazione e valutazione dell'impatto delle attività legate all'innovazione" (MLE- on Innovation Related Procurement), che incoraggia l'approccio multi-metodo di triangolazione nella valutazione delle politiche di appalti pubblici per l'innovazione. Lo studio 1. adotta principalmente: "analisi della legislazione", "ricerca documentale”. Lo studio 2. applica un approccio di mixed-method basato principalmente su "Survey" e "interviste One-to-one" con attori chiave dal lato del committente (coinvolgendo 12 delle 18 pubbliche amministrazioni che hanno gestito PCP in Italia). Lo studio 3. fa leva sulla metodologia del "caso studio" supportata dalla "osservazione partecipativa"; tale studio ha coinvolto Tech4Care Srl, una start up italiana particolarmente attiva nel campo degli appalti PCP. L'analisi dei tre studi ha portato a diverse considerazioni, che possono essere brevemente riassunte come segue. La politica sugli appalti per l'innovazione, sebbene fortemente promossa, è relativamente immatura per quanto riguarda l'attuazione e la valutazione sia a livello nazionale che regionale. L'appalto PCP potrebbe effettivamente rappresentare un'ottima opportunità di crescita dal lato per l’impresa. Il fornitore può sperimentare un notevole miglioramento riguardo lo sviluppo del business grazie all'esperienza dei PCP. Tuttavia, alcuni requisiti preliminari del fornitore potrebbero essere necessari per sfruttare appieno le opportunità del PCP. Anche l’Ente appaltante subisce generalmente impatti positivi diretti e indiretti. Tuttavia, quando un Appalto di Innovazione non segue l'esperienza del PCP, la conoscenza derivante dall'attività di ricerca e sviluppo rimane non sfruttata dal punto di vista dell’attore pubblico. ​
Over the two past decades, the strategical use of public procurement has increasingly become a central theme of European innovation policy. Public Demand for Innovation can improve public services steering technological change towards socially shared objectives. The application of public procurement of goods and services to innovation has thus a triple rationale: (1) the improvement of public services; (2) the incentive of supplier firms to be more innovative; and (3) the pursuit of broader societal goals or missions. Academic debate has, in different perspectives, dealt with the role of public procurement as an innovation driver. From 90', authors interested on the role of procurement as an innovation policy tool or as a tool of industrial policy, have discussed public procurement as one of the critical elements of a demand-oriented innovation policy and have emphasised the role of policymakers in promoting innovation-friendly practices across all types of procurement. Despite the growing awareness of public demand to spur innovation, the investments devoted to adopting innovative solutions in Europe are just above half of the ambition level. This dissertation addresses the theme of innovation procurement by focusing on the implementation of Pre-commercial procurement, which is a relatively new approach to procuring R&D services, defined by the European Commission's COM (2007) 799. The dissertation considers the three key actors involved in the innovation procurement policy implementation: the policymaker, the procurer, and the supplier. By analysing in parallel (and somehow also jointly) these three different perspectives on the Pre-Commercial Procurement experiences, the dissertation aims to evaluate innovation procurement policy in the Italian policy framework. In this respect, the thesis is built upon three original studies: Study 1- The experience in Italian and in the Italian Regions; Study 2- The Procurer’s perspective; Study 3-The Suppliers perspective. The methodology approach for the whole dissertation draws on the "Monitoring, evaluation and impact assessment of innovation-related" (MLE- on Innovation Related Procurement), which encourages the triangulation multi-methods approach in Innovation public procurement policies evaluation. Study 1. primarily adopts: "Legislation analysis", "documentary desk research". Study 2. applies a mixed-method approach mainly based on "Survey" and "One-to-one interviews" with key actors from the procurer's side (involving 12 out of 18 public administration who has run PCP in Italy). Study 3. leverages the "case study" methodology supported by the "participatory observation"; this study involved Tech4Care Srl, an Italian start-up particularly active in the Pre-Commercial procurement field. The analysis of the three studies led to several considerations, which can be briefly picked up as follow. The Innovation procurement policy, although severely promoted, is relatively immature concerning the implementation and evaluation both at the national and regional level. The pre-commercial procurement could effectively represent an excellent opportunity for growing concerning the supply-side. The supplier can experience a strengthened improvement concerning business development due to the PCPs experience. However, some preliminary requirements of the supply-side may be necessary to exploit the PCP opportunities fully. Concerning the procurer-side, the Procuring Entity (PE) generally experiences either direct and indirect positive impacts. However, when a wider PPI does not follow the PCP experience, the knowledge arisen from R&D activity remains unexploited from the Procurer side. ​
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Masini, Alice <1993&gt. "Evaluation of an intervention focusing on children to promote physical activity in the entire community: Feasibility, effectiveness and sustainability over time." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10312/1/PhD_Thesis_Dott.ssa%20Alice_%20Masini.pdf.

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Regular physical activity (PA) during childhood is associated with physical, mental, emotional and social health benefits. The constant practice of PA is considered one of the best buys available in public health. The World Health Organization (WHO) recommends to perform at least 60 minutes per day of moderate to vigorous PA for children and adolescents in order to obtain health benefits. However, globally, this level of PA is hardly achieved. Children and adolescent who do not reach the recommended levels of PA are defined as physically inactive and nowadays physical inactivity constitutes a new type of pandemic. For this reason, the WHO launched a global action plan addressing physical activity with a goal of reducing physical inactivity in children and youth. The plan also included recommendation to improve individual and community health and contribute to the social, cultural and economic development of all nations. Worldwide, children and adolescents spend a significant amount of time in school and for this reason the school represents a fundamental educational setting that can play a pivotal role increasing students’ PA. Opportunities to be physically active should not be considered purely in relation to when children attend physical education classes but also making physical activity available during the school day, such as physically active lessons, and multicomponent PA interventions. Since school-based PA interventions are quite numerous, the present thesis focused on interventions delivered during school hours and that integrate small doses of PA as part of routine instruction. This type of intervention is called “Active Breaks.” Active Breaks consists of brief 5–15 minutes sessions of PA led by teachers who introduce short bursts of PA into the academic lesson. In light of this the present thesis aims to evaluate the feasibility, efficacy and sustainability of an Active Breaks intervention targeting children to promote PA.
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FANELLI, GIULIANO. "Flowering phenology of antrhopogenous plant communities in an urban ecosystem: a useful tool for ecological evaluation and aerobiological monitoring." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2014. http://hdl.handle.net/2108/202053.

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Do, David, and Daniel Ohlsson. "The impact of Task-Technology Fit on user performance within an Applicant Tracking Software : A qualitative study on the Bullhorn system." Thesis, Linnéuniversitetet, Institutionen för informatik (IK), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76762.

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The possibilities that exist with today’s online environments are huge. Today more data than ever before is stored each day in different forms online, and it is steadily increasing. With increasing amounts of data in the online databases, the need for evaluation and optimization in information systems is ever increasing. The field studies within this project was done on demand by a recruitment agency located in Great Britain. The main area of this study was to investigate the user experience and workflow within an applicant tracking software (ATS). With the Task-Technology Fit (TTF) theory as theoretical framework, this study aimed to apply this theory in the evaluation of the ATS called Bullhorn, by evaluating the match between Task characteristic and Technology characteristic through qualitative methods. Results shows how user experience and performance is affected by the current TTF construct.
Möjligheterna i dagens onlinevärld är oändliga. Idag samlas det varje dag in mer data än någonsin innan i olika former online, och detta fortsätter att öka stadigt. Med ökande mängder data i databaserna online, ökar behovet av utvärdering och optimering inom informationssystem. Fältstudierna som genomfördes i detta projekt gjordes på beställning av ett rekryteringsbolag i Storbritannien. Huvudområdet för detta projekt var att undersöka användarupplevelsen och arbetsflödet i en söktjänst för arbetssökande. Med Task-Technology Fit-teorin (TTF) som teoretiskt ramverk var målet med denna studie att applicera denna teori i utvärderingen av söktjänsten Bullhorn, genom att utvärdera matchningen mellan uppgifterna som användarna behöver genomföra och tjänstens tekniska möjligheter via kvalitativa metoder. Resultatet visar hur användarupplevelsen och användarens prestation påverkas av den nuvarande TTF-matchningen.
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ATZORI, ROSSELLA. "Advances in data analysis and survey design of Discrete Choice Experiments: an application to the evaluation of the military presence in Sardinia." Doctoral thesis, Università degli Studi di Cagliari, 2022. http://hdl.handle.net/11584/332567.

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This thesis contributes to the literature on economic valuation with stated preference tools based on Hick’s compensated demand function. Among these methods, Discrete Choice Experiments (DCE) are extensively used for investigating individual preferences and assessing the value of hypothetical projects. Academic efforts over the past few decades have been devoted to improving the ability of choice models to describe behaviour, but some research areas call for further consideration. The present work seeks to enhance the comprehension of preference and process heterogeneity and aims to delve into the design of DCEs. These topics were explored through three case studies focusing on preferences towards the military presence in Sardinia, Italy. Every decision regarding the future of military facilities entails a change in the mixture of benefits and costs experienced by hosting communities and hence needs to be carefully considered given the relevance of this topic in the regional public debate. Chapter 2 investigates preferences for the downsizing of Poligono Interforze del Salto di Quirra. Modelling the socio-psychological roots underlying acceptance of hazardous facilities could better inform assessment of welfare changes, yet this approach is seldom used in project appraisal. This chapter aims at filling this gap, integrating a rich socio-psychological framework with the choice model, resulting in a hybrid choice model with a complex multi-layer structure. Results show that place attachment, sense of community and trust in institutions influence the perception of environmental and health risks, and the perception of economic benefits. The last two factors are negatively correlated and directly influence the utility of the attributes characterising the alternatives, driving the preference toward the proposed scenarios. These findings have important practical implications, giving guidance to calibrate welfare compensations and define policy measures aimed at socio-economic regeneration. Chapter 3 explores the role of alternative decision-making strategies in guiding preferences for the downsizing of Poligono di Capo Teulada and Poligono di Capo Frasca. A finite mixture model is used to allocate respondents to different classes based on decision-making procedures, combining the traditional compensatory behaviour with selection-by-aspects strategies and saliency-led choices. This chapter proposes a latent class model with random parameters (LC RPL) to jointly account for preference and process heterogeneity. Latent class analysis indicates that integrating multiple heuristics in the modelling describes satisfactorily individual behaviour. Findings confirm a superior performance of models integrating process heterogeneity, compared to both the MNL and the RPL models. The LC RPL structure used in this chapter produces more conservative model estimates and favours a richer comprehension of citizen preferences. Chapter 4 aims to test whether and to what extent valence-based attribute framing influences the choice estimates with an application on the regeneration of a former military site (Caserma Ederle, Cagliari). Attribute framing has been investigated only to a limited degree in environmental DCE studies. This chapter contributes to its understanding by focusing on alternative framings for the monetary attribute, using a within-subjects experimental treatment. The reliability of the latter is crucial to calculate welfare change measures. RPL model results show higher disutility for the negatively framed monetary attribute but a less dispersed parameter distribution under the positive treatment. In light of these findings, researchers should acknowledge the relevance of attribute framing, proceeding cautiously when defining attributes and levels of the DCE. Pre-testing different wordings for the payment vehicle is recommended, especially when its choice is not obvious or cannot be based on previous studies.
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35

GIROLETTI, TOA. "MEASURING AUTONOMY THROUGH A SUBJECTIVE EVALUATION." Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/18563.

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All’interno del quadro teorico del Capability Approach ‘agency’ viene definito come ciò che permette agli individui di raggiungere i propri obiettivi. Quando il concetto di ‘agency’ viene studiato attraverso misure soggettive, insorge il problema delle preferenze adattive. Lo scopo di questa Tesi è di testare una metodologia che possa catturare la percezione individuale di ‘agency’ nelle diverse dimensioni che compongono la nostra vita, limitando i problemi di misurazione dovuti delle preferenze adattive. Per questo fine, ci affidiamo al ‘Relative Autonomy Index’. Inoltre, utilizziamo la metodologia di ‘Achoring Vignette’ per aumentare la comparabilità tra le percezioni dei singoli individui. Nella prima parte, indaghiamo se il nostro metodo effettivamente riduce l’incomparabilità individuale attraverso uno studio pilota. I risultati dimostrano come il nostro metodo sia in grado di catturare differenze nel comportamento di risposta. Nella seconda parte, sulla base di una seconda raccolta di dati, applichiamo la nostra metodologia al fine di indagare l'impatto dei Gruppi di Acquisto Solidale sul livello di autonomia di un gruppo di produttori italiani. I nostri risultati indicano che il coinvolgimento con i Gruppi di Acquisto Solidale evita la riduzione dell'autonomia percepita dai quei produttori che non sono coinvolti con i Gruppi di Acquisto Solidale.
Within the Capability Approach, agency is one of the components that enable individuals to be empowered. When subjective measures are applied to the study of agency, the problem of ‘adaptive preferences’ arises. The aim of this thesis is to test a methodology that captures the individual perception of agency, while taking into account the bias coming from adaptive preferences. We rely on the Relative Autonomy Index to capture the individual’s agency in several dimensions. In addition, in order to increase the comparability between the individual’s perceptions, we employ the Anchoring Vignette methodology. We investigate whether our methodology reduces the individual incomparability through a pilot study. The results of this preliminary exercises show that our methodology is able to capture dissimilarities in response behaviours. Through a second data collection, we apply our methodology in order to investigate the impact that the commercial relationship between Solidarity Purchasing Group and Italian producers has on the latter. Our findings suggest that the involvement in the Solidarity Purchasing Group has a mainly positive impact on producers’ level of autonomy, which remains at lower levels for producers that did not develop a relationship with the Solidarity Purchasing Group.
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36

GIROLETTI, TOA. "MEASURING AUTONOMY THROUGH A SUBJECTIVE EVALUATION." Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/18563.

Full text
Abstract:
All’interno del quadro teorico del Capability Approach ‘agency’ viene definito come ciò che permette agli individui di raggiungere i propri obiettivi. Quando il concetto di ‘agency’ viene studiato attraverso misure soggettive, insorge il problema delle preferenze adattive. Lo scopo di questa Tesi è di testare una metodologia che possa catturare la percezione individuale di ‘agency’ nelle diverse dimensioni che compongono la nostra vita, limitando i problemi di misurazione dovuti delle preferenze adattive. Per questo fine, ci affidiamo al ‘Relative Autonomy Index’. Inoltre, utilizziamo la metodologia di ‘Achoring Vignette’ per aumentare la comparabilità tra le percezioni dei singoli individui. Nella prima parte, indaghiamo se il nostro metodo effettivamente riduce l’incomparabilità individuale attraverso uno studio pilota. I risultati dimostrano come il nostro metodo sia in grado di catturare differenze nel comportamento di risposta. Nella seconda parte, sulla base di una seconda raccolta di dati, applichiamo la nostra metodologia al fine di indagare l'impatto dei Gruppi di Acquisto Solidale sul livello di autonomia di un gruppo di produttori italiani. I nostri risultati indicano che il coinvolgimento con i Gruppi di Acquisto Solidale evita la riduzione dell'autonomia percepita dai quei produttori che non sono coinvolti con i Gruppi di Acquisto Solidale.
Within the Capability Approach, agency is one of the components that enable individuals to be empowered. When subjective measures are applied to the study of agency, the problem of ‘adaptive preferences’ arises. The aim of this thesis is to test a methodology that captures the individual perception of agency, while taking into account the bias coming from adaptive preferences. We rely on the Relative Autonomy Index to capture the individual’s agency in several dimensions. In addition, in order to increase the comparability between the individual’s perceptions, we employ the Anchoring Vignette methodology. We investigate whether our methodology reduces the individual incomparability through a pilot study. The results of this preliminary exercises show that our methodology is able to capture dissimilarities in response behaviours. Through a second data collection, we apply our methodology in order to investigate the impact that the commercial relationship between Solidarity Purchasing Group and Italian producers has on the latter. Our findings suggest that the involvement in the Solidarity Purchasing Group has a mainly positive impact on producers’ level of autonomy, which remains at lower levels for producers that did not develop a relationship with the Solidarity Purchasing Group.
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37

BATTARRA, Mattia. "Performance evaluation in external gear pumps: numerical and experimental methods." Doctoral thesis, Università degli studi di Ferrara, 2018. http://hdl.handle.net/11392/2478774.

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La tesi riporta i risultati ottenuti durante il corso di dottorato frequentato negli ultimi tre anni. La mia attività di ricerca si è concentrata sullo sviluppo di modelli matematici per la previsione delle prestazioni di pompe ad ingranaggi, focalizzando l’attenzione sull’analisi di caratteristiche specifiche quali l’uso di ingranaggi elicoidali, rapporto di trasmissione non unitario e la necessità di studiare un'ampia gamma di velocità operative. Tali aspetti, solitamente inusuali nelle applicazioni classiche, costituiscono oggi requisiti standard nei sistemi automobilistici ausiliari ad alte prestazioni, in abbinamento ai tipici vincoli di affidabilità, comportamento NVH ed efficienza. In questo contesto, la disponibilità di modelli robusti rappresenta un valore aggiunto durante tutto il processo di progettazione e sviluppo. Per tale motivo, durante la mia attività di ricerca ho affrontato la tematica da diverse prospettive, dal momento che le moderne pompe volumetriche devono soddisfare simultaneamente requisiti eterogenei. Il comportamento NVH della pompa è stato analizzato tramite un modello dinamico discreto a sei gradi di libertà, tenente conto della non linearità legata al backlash e di cuscinetti flessibili. Il modello è stato utilizzato per uno studio parametrico atto a valutare l’effetto di diverse pressioni di mandata, la presenza di picchi di pressione nel volume intrappolato dipendenti dalla velocità e varie estensioni della zona di pressurizzazione. Il risultato è un modello minimale per studiare la dinamica di pompe ad ingranaggi basato su un numero limitato di parametri progettuali, caratteristica che lo rende un valido strumento nella fase iniziale del processo di progettazione, quando la geometria dettagliata deve ancora essere definita. L'originalità del presente lavoro risiede proprio nell'approccio proposto, che differisce dai metodi classici basati sulla completa definizione della geometria per ottenere un’elevata accuratezza dei risultati. Le prestazioni delle pompe a ingranaggi sono state valutate anche in termini di efficienza volumetrica e di distribuzione di pressione all'interno dell’ingranaggio, utilizzando un approccio zero-dimensionale che ha portato alla realizzazione di un modello dove la fluidodinamica è accoppiata ai micro-moti dell’ingranaggio stesso. I due fenomeni fisici sono reciprocamente risolti, ad ogni step di calcolo, ottenendo così una stima accurata del comportamento della pompa. Inoltre, la possibilità di studiare sia ingranaggi a denti dritti che elicoidali e con rapporto di trasmissione non unitario è stata inclusa nel modello, al fine di garantirne l'ampia applicabilità nelle soluzioni progettuali moderne. I risultati sono stati confrontati con dati sperimentali ottenuti da una campagna sperimentale dedicata, eseguita su 20 esemplari di pompa nominalmente identici, ciascuno testato in 16 diverse condizioni di lavoro. L’analisi ha dimostrato che l'approccio proposto garantisce previsioni accurate in termini di efficienza volumetrica nell'ambito delle condizioni di lavoro considerate. Al fine di estendere la panoramica dei potenziali fenomeni che possono verificarsi nei progetti di design moderni, l'ultima parte della tesi descrive una tecnica sperimentale per la rilevazione di cavitazione incipiente in pompe ad ingranaggi esterni mediante misure vibro-acustiche. La problematica è stata studiata su quattro diversi prototipi di pompe, rilevando la presenza di cavitazione con una post-elaborazione dedicata, applicata ai segnali ottenuti da un idrofono, un accelerometro ad alta frequenza e due trasduttori di pressione. Il confronto tra pompe cavitanti e non-cavitanti ha sottolineato l'effettiva capacità della tecnica diagnostica e la necessità di ulteriori approfondimenti su questo argomento, che non è mai stato affrontato sperimentalmente in letteratura, per una più profonda comprensione delle sue caratteristiche.
The thesis reports the results I obtained throughout the PhD course that I have attended for the last three years. My research activity focused on developing mathematical models for predicting gear pump performance, with a particular attention on specific features including helical gears, non-unitary transmission ratio and the need to investigate a wide operating speed range. Such peculiar aspects, usually uncommon in fluid power applications, nowadays constitute standard requirements of high performance automotive auxiliary systems to be matched with classic constraints regarding reliability, NVH behavior and efficiency of the machine itself. Within this framework, robust numerical models represent powerful tools for engineers throughout the entire design process. For this reason, during my research activity I developed methods performance prediction from different perspectives, since modern volumetric pumps must match heterogeneous requirements simultaneously. The pump NVH behavior has been addressed by means of a discrete dynamic model, accounting for backlash nonlinearities and based on a six degrees of freedom system with flexible bearings. Dynamic loads due to the pressure field around the gears are estimated by means of an analytical procedure, as well as speed dependent friction torque. A parametric study has been conducted to evaluate the effects of different outlet pressures, presence of speed dependent high pressure peaks in the trapping volume and various pressurizing zone extensions. The result is a minimal model to study the dynamics of gear pumps based on a limited number of design parameters. These features make it a powerful tool at the early stage of the design process, when the detailed geometry is still to be defined. The originality of the present work stands in the proposed approach itself, which differs from classical methods based on the detailed definition of the pump geometry to reach high accuracy results. Gear pump performances have been evaluated also in terms of volumetric efficiency and pressure phenomena occurring within the gearpair by using a zero-dimensional approach. This model couples the effects of the fluid-dynamic field and the gearpair micromotions on the basis of a novel set of equations. The two phenomena are reciprocally solved, at each time-step, to obtain an accurate estimation of the pump behavior, which is reached by considering multiple load sources. Possibility to study both spur and helical gears and non-unitary transmission ratio gearpairs has been included, in order to ensure the wide applicability of the model in modern design solutions. Results assessment has been achieved by means of a dedicated experimental campaign, involving measurements on 20 nominally identical samples of the same pump design, each one tested at 16 different working conditions. The comparison demonstrated that the proposed approach guarantees high accuracy predictions in terms of volumetric efficiency within the range of working conditions considered. In order to extend the overview of the potential phenomena that may occur in modern design projects, the last part of the thesis introduces an experimental technique for detecting incipient cavitation in external gear pumps by means of vibro-acoustic measurements. The phenomenon has been investigated on four different pump prototypes, where marks of cavitation have been captured with a dedicated post-processing technique applied to signals obtained with a hydrophone, a high frequency accelerometer and two pressure ripple transducers. Comparison between cavitating and not-cavitating pumps has underlined the effective capability of the procedure in detecting the phenomenon and the necessity of further investigations on this subject, which has never been experimentally addressed in the literature, for a deeper understanding of its characteristics.
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38

Passarini, Chiara. "Performance evaluation and safety improvement of Cable Driven Robots." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3427297.

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Cable Driven Robots are a new class of parallel manipulators in which rigid links are replaced by cables. They are widely suggested for applications involving wide workspaces and high payloads. Moreover, their simple and light design makes them inexpensive and reconfigurable. However, besides all these advantages, only few examples of successful applications are present outside research laboratories. The most well known one is the cable suspended camera system in stadiums and arenas. Even if these devices are widely employed in public and crowded areas, close to or even in contact with humans, an emergency stop in case of failure or cable breakage is not yet available. Indeed, managing safety in cable driven robots is more difficult than in conventional manipulators with rigid links. In particular, an abrupt brake of the actuated joints is not a sufficient condition to ensure the arrest of the end effector. The objective of this thesis is to investigate safety issues in cable driven robots and propose recovery approaches to apply in case of failure. The need of safety is proven by many examples of malfunctions or accidents involving cable camera systems around the world. By studying the performance of cable driven robots before and after failure, new algorithms are proposed to deal with cable breakage and keep the end effector under control in emergency conditions. The first part of the thesis presents an overview of cable driven robots, including classification, modeling and performance evaluation. The second part focuses on after failure recovery approaches. Two different strategies are proposed to lead the end effector towards a safe configuration following a feasible path and avoiding further damages. The proposed strategies are tested on a real prototype to prove their effectiveness and the experimental results are discussed in the last part of this dissertation.
I robot a cavi sono una classe di manipolatori innovativa nell’ambito della robotica. Risultano particolarmente vantaggiosi nei campi in cui si richiede un ampio spazio di lavoro o la capacità di sollevare carichi ingenti. Il loro design semplice e leggero li rende notevolmente economici e facilmente riconfigurabili. Nonostante gli innegabili vantaggi, i robot a cavi sono ancora scarsamente diffusi in applicazioni che esulano dalla ricerca. L’applicazione più nota e di maggior successo è probabilmente quella delle telecamere sospese, impiegate in stadi e palazzetti. Nonostante l’uso intensivo di questa tecnologia in aree pubbliche ed affollate, non è ancora presente un efficiente sistema di emergenza. Infatti, un improvviso blocco dei motori non assicura l’arresto del dispositivo, come invece accade per i robot tradizionali a membri rigidi. Lo scopo di questa tesi è quello di analizzare le problematiche legate alla sicurezza nei robot a cavi e proporre nuove soluzioni da attuare in caso di malfunzionamento per assicurare l’arresto dell’organo terminale. La necessità di un’efficiente strategia per gestire i guasti è provata dai numerosi incidenti riguardanti le telecamere sospese avvenuti in tutto il mondo. La prima parte della tesi presenta una panoramica sui robot a cavi, considerando classificazione, modellazione e valutazione delle prestazioni. Successivamente, la tesi presenta due diverse possibili strategie da attuare in caso di rottura di uno o più cavi per garantire l’arresto in sicurezza dell’organo terminale mentendo la tensione su tutti i cavi rimanenti. Le strategie verrano quindi testate considerando un prototipo di robot a cavi sospeso e planare. Seguiranno poi i risultati sperimentali nella parte finale della tesi dove verranno discusse fattibilità ed affidabilità di entrambe le strategie.
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39

ZAMBELLI, VANESSA. "Pet imaging for evaluation of inflammatory response in a murine model of acute respiratory failure." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/43295.

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Background: Acute Respiratory Distress Syndrome (ARDS) is a life-threatening form of acute respiratory failure, with a still high mortality. Aspiration pneumonitis is a clinical disorder that, entailing a direct lung injury, is associated to ARDS. It is characterized by an acute inflammatory response with neutrophilic recruitment into the lung and a late fibrotic evolution of injury. This study investigates whether the use of PET could allow to monitor this inflammatory response and its correlation with the later fibroproliferative phase in an experimental model of acute respiratory failure. Since to date no specific therapeutic strategies are available for ARDS patients, we tested the effects of exogenous surfactant treatment on lung injury evolution, by monitoring it with CT-PET imaging. Methods: Hydrochloric acid (0,1M) was instilled (1,5 ml/kg) into the right bronchus of mice. The study was divided into three parts. Time-course experiment: four groups of mice underwent micro-CT and micro-PET scans and sacrificed at different time point (6hrs, 24 hrs, 48 hrs and 7 days after surgery) to assess arterial blood gases, histology and bronchoalveolar lavage (BAL). Long-term experiment: one group of mice underwent a micro-CT scan 1 hour after lung injury and a series of [18F]FDG-PET at the same time points. 21 days after respiratory static compliance was measured and lung tissue was collected in order to measure the OH-proline content. Treatment experiment: two groups of mice were treated with exogenous surfactant (Curosurf ®) or vehicle (sterile saline 0.9 %) three hours after HCl instillation. Animals underwent micro-CT and a series of micro-PET scans. 21 days after they were sacrificed to measure lung mechanics and collagen deposition. Results: Histological analysis showed a rapid recruitment of neutrophils into the damaged lung 6 hours after injury, with a peak after 24 hours. Macrophages, as expected, reached the peak after 48 hours. [18F]FDG signal, as inflammation marker, showed similar time course to that of recruited inflammatory cells (sum of two cell types). Mice that were sacrificed 21 days after the surgery were characterized by a correlation between a reduced respiratory static compliance and a high PET signal 7 days after lung injury. PET signal correlated also with collagen content. This correlation was confirmed in treatment experiment, in which we found that exogenous surfactant administration improved lung fibrotic evolution, by reducing collagen deposition. Conclusions: This study demonstrated the possibility to use PET imaging to follow the inflammatory response also in longitudinal studies. Moreover a correlation between a persistence of inflammatory process and fibrotic evolution was showed. We speculate that it is possible that acute treatments of the inflammation capable of reducing the fibroproliferative process, could be monitored using the FDG-PET method.
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40

Renzi, Maria Teresa <1983&gt. "Effects of pesticides on honey bees (Apis mellifera L.): study of a specific route of exposure and evaluation of biochemical-physiological changes in the assessment of the pesticides toxicity." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5699/1/RENZI_MARIATERESA_TESI.pdf.

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In this study, some important aspects of the relationship between honey bees (Apis mellifera L.) and pesticides have been investigated. In the first part of the research, the effects of the exposure of honey bees to neonicotinoids and fipronil contaminated dusts were analyzed. In fact, considerable amounts of these pesticides, employed for maize seed dressing treatments, may be dispersed during the sowing operations, thus representing a way of intoxication for honey bees. In particular, a specific way of exposure to this pesticides formulation, the indirect contact, was taken into account. To this aim, we conducted different experimentations, in laboratory, in semi-field and in open field conditions in order to assess the effects on mortality, foraging behaviour, colony development and capacity of orientation. The real dispersal of contaminated dusts was previously assessed in specific filed trials. In the second part, the impact of various pesticides (chemical and biological) on honey bee biochemical-physiological changes, was evaluated. Different ways and durations of exposure to the tested products were also employed. Three experimentations were performed, combining Bt spores and deltamethrin, Bt spores and fipronil, difenoconazole and deltamethrin. Several important enzymes (GST, ALP, SOD, CAT, G6PDH, GAPDH) were selected in order to test the pesticides induced variations in their activity. In particular, these enzymes are involved in different pathways of detoxification, oxidative stress defence and energetic metabolism. The results showed a significant effect on mortality of neonicotinoids and fipronil contaminated dusts, both in laboratory and in semi-field trials. However, no effects were evidenced in honey bees orientation capacity. The analysis of different biochemical indicators highlighted some interesting physiological variations that can be linked to the pesticide exposure. We therefore stress the attention on the possibility of using such a methodology as a novel toxicity endpoint in environmental risk assessment.
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41

Renzi, Maria Teresa <1983&gt. "Effects of pesticides on honey bees (Apis mellifera L.): study of a specific route of exposure and evaluation of biochemical-physiological changes in the assessment of the pesticides toxicity." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5699/.

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In this study, some important aspects of the relationship between honey bees (Apis mellifera L.) and pesticides have been investigated. In the first part of the research, the effects of the exposure of honey bees to neonicotinoids and fipronil contaminated dusts were analyzed. In fact, considerable amounts of these pesticides, employed for maize seed dressing treatments, may be dispersed during the sowing operations, thus representing a way of intoxication for honey bees. In particular, a specific way of exposure to this pesticides formulation, the indirect contact, was taken into account. To this aim, we conducted different experimentations, in laboratory, in semi-field and in open field conditions in order to assess the effects on mortality, foraging behaviour, colony development and capacity of orientation. The real dispersal of contaminated dusts was previously assessed in specific filed trials. In the second part, the impact of various pesticides (chemical and biological) on honey bee biochemical-physiological changes, was evaluated. Different ways and durations of exposure to the tested products were also employed. Three experimentations were performed, combining Bt spores and deltamethrin, Bt spores and fipronil, difenoconazole and deltamethrin. Several important enzymes (GST, ALP, SOD, CAT, G6PDH, GAPDH) were selected in order to test the pesticides induced variations in their activity. In particular, these enzymes are involved in different pathways of detoxification, oxidative stress defence and energetic metabolism. The results showed a significant effect on mortality of neonicotinoids and fipronil contaminated dusts, both in laboratory and in semi-field trials. However, no effects were evidenced in honey bees orientation capacity. The analysis of different biochemical indicators highlighted some interesting physiological variations that can be linked to the pesticide exposure. We therefore stress the attention on the possibility of using such a methodology as a novel toxicity endpoint in environmental risk assessment.
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42

MATA, ELIDA. "EVALUATION OF SURVEILLANCE SYSTEM OF INFECTION DISEASES AND VACCINATION COVERAGE IN ALBANIA." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/169570.

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Introduction The Albanian system of epidemiological surveillance for infectious diseases has been and continues to be mandatory: the infectious diseases included in this system should be reported by law. The statutory notification system dates from the years ’50. In spite of small improvements over the time, the essential features of the system remained as before until 1998. Before the years ’98, the surveillance system have had registered a shortage and deficiency on the information flow on infectious diseases due to the non application of active and sentinel epidemiological surveillance, related directly to quantitative and qualitative shortage of the existing form of mandatory reporting of infectious diseases. Today in Albania, the information flow on infectious diseases has been realized and continues to be realized through the monthly reporting form (named-14/Sh). The monthly reporting form of infectious diseases (14/Sh) is compiled by the epidemiological service in the district level and sent to the Department of Epidemiology and Biostatistics at the Public Health Institute (under the direction of the Minister of Health nr.189, dt.08.08.1995, and the approval of the Statistical Institute, 134 letters, dated, 08.25.1995). The monthly data are collected by the departments of epidemiology in the 36 districts from general practitioners, hospitals and laboratories. Surveillance system in Albania has in use 4 cards of notification. Group A (14-1/Sh) includes infectious diseases of the utmost importance to public health, group B / 1 (14-2/Sh) are those for which there is an obligation to notify rapid (within 1-3 days), group B / 2 (14-3/Sh) includes tuberculosis diseases and group B / 3 (14-4Sh) sexually transmitted diseases. Regarding the immunization system has started at the end of the 1950 with diphtheria toxoid and later with DT and DTP in the early 1970s, tuberculosis vaccine (BCG), measles and polio vaccine. After 1993, in the immunization calendar are included other vaccines such as viral hepatitis B, trivalent vaccine (measles, rubella and mumps) and at the end homophiles’ influenza type B which is introduced in 2009. Since 1993, UNICEF started to provide the whole vaccines according to the WHO recommendation for immunization. In 1995, Ministry of Health in Albania introduced also the immunization against hepatitis B for all newborns. After the year 1993 in the immunization calendar have been introduced the following vaccines: 1995 - Viral hepatitis B, 2000 – bivalent vaccine of measles & rubella (MR) 2005 – trivalent vaccine measles, mumps and rubella (MMR) 2009 – penta-vaccine DTP + Hep.B + HiB (influenza hemophilus B). The Research Objectives The evaluation of the current system of infectious diseases surveillance in Albania during the period 1998-2009 in order to identify the critical issues and existing possibilities for improvement This objective will be carrying out through: 1. Evaluation of epidemiological situation of these diseases by focusing attention on: description of the trend of infectious diseases in Albania during the period of study (data from the monthly reporting forms) and the evaluation of the information by the individual form of infectious diseases notification; distribution of the infectious diseases by sex and age; distribution by the regions and the areas (urban and rural); assessment of the vaccine coverage for vaccine preventable diseases in Albania; comparing of the levels of infectious diseases and our surveillance system with those of other European countries. 2. Analysis of the characteristics of the surveillance system (the way of completing the individual forms) in terms of sensitivity of recording the cases of infection, emphasizing the importance of the system and making a balance between the strengths and weaknesses points of the system, in order to implement of the measures to improve the monitoring of infectious diseases and the introduction of surveillance systems for specific diseases. 3. Assessment of the organizational structure of the monitoring system, trying to find out any restrictions on the management of data from local levels of health; 4. Providing a comparison of surveillance system on infectious diseases through the intersection of monthly and individual data to assess and calculate the percentage of cases reported by the monthly reporting forms and individual form and to understand the inadequacy of data with the ultimate goal of improving the current system of surveillance on infectious diseases. The Material and Method It 'was built a database specifically for processing data relating to all infectious disease notifications and conduct an analysis of the criticality of the system in terms of data quality and simplicity of the system according to the criteria of the CDC (2004). There are included all the reported infectious diseases from the monthly reporting system for the period 1998-2009 and there are assessed individual notification forms of infectious diseases which constitute the key point of the system of surveillance of these diseases from which depends and quality and reliability of monthly reporting data. The analysis was based on general information related to the total number of cases from monthly reporting system in order to describe the trends and key variables of infectious diseases under the study, and the data reported by the individual notification forms, so that makes an assessment of the system through cross-analysis of data. Results The main problems found were the poor quality of data and system organization. Individual notification forms consist of the following parts: general information of the patient, the history of the disease, laboratory diagnosis, epidemiological investigation and conclusion. Regarding the individual notification for Measles, Mumps, Rubella, Diphtheria, Tetanus, Pertussis and Poliomyelitis are not completed the individual forms. The diagnosis for these diseases is established only by clinical symptoms. About the quality of data it is concluded that there is a lack of information regarding to: 1. Characteristics of the person (personal data and address) • Diarrheal diseases (typhoid fever, salmonellosis, shigellosis, poisoning) – 40% of cases present lack of the father's name usually indicated in Albania (source of inaccuracy in identifying the subject). • Viral Hepatitits and zoonoses diseases – 20% of them present lack of the father’ name • Pulmonary tuberculosis – 45% of cases present lack of the father’ name; 20% of them present lack of data onset and starting of therapy and 26% of cases present lack of hospital admission; • Other diseases of infectious diseases – present in 40% of cases lack of father’ name and in 20% of them lack of patient address. 2. Characteristics of the disease (laboratory diagnosis) • Diarrheal diseases – in 30% of cases is not complete "laboratory confirmation" field; • Viral hepatitis - in 60% of cases is not complete "laboratory diagnosis" field (especially since 2001 we have confirmed no case for hepatitis A, B and C); in 51% of cases is not shown hospital and in 37% is not complete the evolution of the disease • Zoonoses diseases present in 70% of cases lack of diagnostic confirmation (is not complete the laboratory diagnosis) • Pulmonary tuberculosis – in 45% of cases is “missing” for laboratory confirmation • Regarding the vaccine preventable diseases, data on the subject of previous vaccination is only reported in 63% of cases. • Other infectious diseases – present over 70% of cases lack of laboratory diagnosis 3. Epidemiological investigation The third part presents individual data form about the outbreak nature and infectious origin. Percentages of lack of data are presented as follows: • Diarrheal diseases – in 40% of cases is not complete for outbreak nature and in 8% of them is completed the infectious origin • Viral hepatitis - in 30% of them is not completed the outbreak nature and in 0.6% is completed the infectious origin • Zoonosis diseases – in 60% of cases is not completed the infectious origin field • Pulmonary tuberculosis – present uncompleted field of infectious origin in 20% of cases • Other infectious diseases – in 55% of cases have not information regarding the infectious origin of diseases. 4. Conclusion part of individual notification form Regarding the “Conclusion” part of the individual notification form in the highest percentage the diseases are confirmed, although the laboratory diagnosis is not performed. Conclusion The data produced by the system does not reach a satisfactory quality and is a clear need to revamp the system: the first intervention should be aimed at improving the performance of microbiology laboratories in the laboratory that allows the detection of disease etiology, in addition the system surveillance must be better defined with respect to flows and information tools as well as the timing of data transmission. As part of our analytical work we have already built a new notification card, simplified in some places and made easier to complete, this card will probably be introduced for an initial pilot phase in 6 of the Albanian districts by the end of 2010. This work is also related to the training of operators involved in the reporting of infectious diseases.
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GODA, NIZAR FAHMI MOHAMED SALEM. "THE MICROBIOTA ASSOCIATED WITH THE INVASIVE POPILLIA JAPONICA (COLEOPTERA: SCARABAEIDAE) AND EVALUATION OF ENTOMOPATHOGENIC ACTIVITY OF THE ISOLATED NEMATODES." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/702594.

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Popillia japonica Newman (Coleoptera: Scarabaeidae) is a highly polyphagous invasive beetle originating from Japan. It attacks more than 300 plant species, causing severe damage, and can adapt rapidly to new environments. Recently, several studies have been carried out in order to study insect-associated microorganisms and their impact on insect physiology. These microbiota-based studies have also investigated the impact of symbionts on their host’s potential to adapt to changing conditions, thus contributing to an insect’s invasive potential. However, to date, no study has been reported regarding the microbial community associated with P. japonica and the factors that may influence the composition of these communities. Therefore, our group decided to investigate the bacterial community associated with P. japonica at different developmental stages (i.e., larvae, pupae and adults (male, female) using NGS approaches. The aim of this thesis is to investigate the microbiota associated with the three gut regions of different developmental stages of P. japonica (i.e., larvae, pupae and adults) in order to address the following biological questions: 1) Do the developmental stages (i.e., larvae vs. adults) influence the bacterial community associated with P. japonica? 2) Are the bacterial communities which are associated with the three gut regions different? 3) Does the soil have an impact on shaping the bacterial community associated with the different developmental stages of P. japonica (i.e., larvae, pupae and adults)? Further, we seek to: 4) investigate the isolation and molecular characterization of the nematode associated with the third larvae of P. japonica and the microbiota associated with the isolated nematode and 5) test the entomopathogenic activity of the nematode associated with the third larvae of P. japonica. Regarding the P. japonica bacterial community, our results show that soil microbes represent an important source of gut bacteria for P. japonica larvae; but, as the insect develops, its gut microbiota richness and diversity decrease substantially. These changes are in parallel with changes in community composition. Regarding the nematode associated with the third larvae of P. japonica, the results of both the BLAST search and the reconstruction of a phylogenetic tree using the maximum-likelihood method from 18S rRNA sequences confirm the attribution of the isolated nematode to the genus Oscheius. The isolated nematode leads to the mortality of more than 50% of the host after five days. The microbiota study of the nematode shows that its bacterial community is dominated by bacteria belonging to the genus Ochrobactrum, which includes entomopathogenic species.
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CORONEL, VARGAS GABRIELA FERNANDA. "microRNA pattern in tumoral lung tissues from former- and non-smokers: a possible footprint for environmental and genetic risk factors evaluation." Doctoral thesis, Università degli studi di Genova, 2022. http://hdl.handle.net/11567/1076067.

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For the last decade the interest of microRNA as a possible early biomarker for lung-cancer has increased. Less attention has been focused in using microRNA as a biomarker to study the contribution of environmental exposure to air pollutants in non-smokers lung cancer patients. The aim of this thesis is the identification of environmental related microRNA pattern in collected tissues from a total of 64 formal- and non- smoker patients recruited in a three-year observational study. The identified patterns may be used as early predictors of lung cancer, as well as environmental-related footprints. Through microRNA-chip array analysis of lung tissue, it was studied the expression of 2549 microRNAs. A differential analysis between healthy and tumoral tissue showed the presence of 273 microRNA differentially regulated, 222 were down-regulated and 51 up-regulated. Differential analysis was also applied to identify environmental pollution related microRNAs and finding microRNA deregulation in Passive Smoking at home (n=8), Passive smoking at work (n=1), Vehicle traffic at home (n=53), home distance from Etna Volcano (n=21), and home Type radon risk (n=19) exposures. A second biomarker, Benzo(a)Pyrene-DNA adducts levels in blood, was also studied to understand its correlation to the above-mentioned environmental factors. The specificity of this biomarker was minor than microRNA pattern biomarker, but it was strongly correlated to vehicle traffic pollution. The analysis of the microRNA environmental signatures indicates the contribution of environmental factors to the analysed lung cancers in the following decreasing rank: (a) vehicle traffic, (b) passive smoke, (c) radon, and (d) volcano ashes. These results provide evidence that microRNA analysis can be used to investigate the contribution of environmental factors in human lung cancer occurring in non-smokers
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ALBERTI, VIOLETTI SILVIA. "MYCOSIS FUNGOIDES AND SEZARY SYNDROME THE JANUS BIFRONS OF THE CUTANEOUS T-CELL LYMPHOMAS: EVALUATION OF SPECIFIC PHENOTYPE AND GENETIC ALTERATIONS." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/813859.

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Mycosis fungoides (MF) and Sézary syndrome (SS) are two variants of cutaneous T-cell lymphomas (CTCL). These entities are considered two distinct diseases, based on phenotypic and genetic analyses. Neoplastic cells in MF seem to derive from T effector memory cells, instead, neoplastic SS cells have a central memory (TCM) profile. Moreover, evidence of a resident memory T cell (TRM) profile in early-stage MF, compared to migratory memory T cells (TMM) profile in advanced-stage MF, seems to explain the clinical behavior of MF during progression. Recent studies have shown more heterogeneity in CTCL phenotypes compared to that theory. Differences between MF and SS also involve the microenvironment, which predominantly expresses Th1 phenotype compared to Th2 phenotype in advanced stages and SS. A series of studies have identified multiple molecular changes in CTCL, showing a heterogeneous landscape of numerous genetic alterations without a strong differential signature between the two diseases. Molecular mutations could be found more frequently in the pathways of epigenetic and/or chromatin regulation, TCR and T-cell/ cytokine signaling, JAK/STAT signaling, and phosphoinositide 3-kinases (PI3K)/protein kinase B (Akt) and NF-kB pathway. The aim of this project is to delineate the differences between MF and SS about the phenotypic and genetic point of view, taking into account all stages of the diseases. In the first phase of the project, 15 patients with a new diagnosis of MF and SS were selected, including 5 early-stage MF (IA-IIA), 3 advanced MF (2 III MF, 1 IIB MF), 5 classical SS, 2 non-erythrodermic SS. Neoplastic T-cell immune phenotypes were evaluated on paraffin-embedded formalin-fixed sections of skin biopsies and on CD4+CD7- sorted T cells of the peripheral blood by flow cytometry (except for two CD7+ cases). About the 3 patients with stage IB MF, two of them revealed a TRM phenotype (CD69+CD103+CCR7-CD62L-). In the third of them, T cells aberrantly showed expression of CD69 and also CD62L. One IIA-MF patient showed expression of CD69 and CD103 (TRM markers) but also a partial expression of CCR7 with the negativity of CD62L, as TMM phenotype. Erythrodermic and tumoral MF patients were characterized by an infiltrate with a TMM phenotype. In SS, 3 patients showed a typical TCM phenotype (CD45RO+CD27+CCR7+CD62L+). Out of 5 CD45RA+ cases, 4 of them evidenced a T naïve phenotype (CD62L+), including an early MF (IIA). One SS showed complete negativity of CD62L and CCR7, arguing a TEMRA phenotype. Immunophenotype of blood samples revealed a better correlation with the skin of SS patients compared to MF patients. Neoplastic T cells in MF mainly had a Th1 phenotype, also in advanced stages, compared to Th2 phenotype of SS patients. This first step of the project confirmed that MF and SS are characterized by heterogeneity of phenotypes with partial correlation to the clinical features. Evidence of the same TCM phenotype in patients with classical and atypical SS suggests that criteria of this disease should be revised, including also non-erythrodermic forms. In the second phase of the project, we performed a gene expression analysis using a 770-genes panel by NanoString technologies (PanCancer Immune Profiling Panel). To obtain more statically significant data, we included 95 FFPE slides of CTCL. Total RNA from 87 samples was extracted (36 SS and 51 MF at any stage). NanoString data were processed and statistical analysis was performed within the statistical environment R. A principal component analysis was performed on all samples together, but we found a homogeneous group without any evidence of clustering between MF and SS. So, we decided to study separately the two entities. About MF, 12 differentially expressed genes (DEGs) between advanced stages and early stages were found (p-value <0.01): 9 of them resulted upregulated (CCR3, PRAME, FPR2, PMCH, AMBP, TRL7, TNFRSF10C, CFI, HAVCR2) and 3 were down-regulated (KLRB1, CD1B, CD5). Gene ontology (GO) enrichment analysis showed that those genes were significantly enriched in the regulation of the immune system, macrophage activation and Toll-like receptor (TLR) signaling. (FDR <0.05) KEGG pathways analysis revealed a not significantly representation in any pathways. Then, MF cohort was divided into two groups based on the median expression for each gene and the effects of high or low expression levels on OS were examined using the Kaplan-Meier (KM) survival curve. A list of 39 genes was identified as significant associated with OS (p-value <0.05). The HRs and p-values of those selected 39 genes were calculated through Cox regression model, revealing a 9-genes signature, which did not match with DEGs but showed a high significance from KM survival analysis. The increased expression of the following genes is significantly associated with poor prognosis: CDK1 (HR=2.06), IL6ST (HR=1.49), CCR4 (HR=1.66), ITK (HR=1.78), NOS2A (HR=1.38), IL2RA (HR=2.06), LRRN3 (HR=1.39), DUSP4 (HR=1.74). Instead, the lower expression of CCL26 (HR=0.53, p-value 0.028) is significantly associated to poor prognosis. A prognostic score was developed based on the incidence of each gene of the signature on overall survival and was defined as the linear combination of logarithmically transformed gene expression levels weighted by average Cox regression co-efficient. Patients with a high score of expression of the signature had a significantly poorer prognosis compared to patients with a low score (p-value < 0.05). Similarly, considering advanced versus early stages, the two groups with high score confirmed to have a statistically significant poorer prognosis compared to low score (p-value <0.05). This result is particularly evident comparing the score in early stages. KEGG pathway analysis showed that the 9-genes signature was significantly enriched in cytokine and JAK-STAT signaling. For SS samples, we did not evaluate DEGs because of the absence of different stages like in MF, but we performed the same analyses based on OS. A 14-gene signature was found, characterized by the association of their high expression and poor prognosis. The genes identified were IL12A (HR=2.12), IL5RA (HR=2.80), IFNL2 (HR=2.21), NT5E (HR=1.97), IL18RAP (HR=1.89), ABCB1 (HR=1.74), CCL16 (HR=1.89), CCL1 (HR=1.95), IL22RA2 (HR=1.67), IFNA17 (HR=1.69), C9 (HR=1.79), CCR9 (HR=3.31), SPANXB1 (HR=1.62), TREM1 (HR=1.76). We applied the prognostic score, showing that patients with a high score had a worse prognosis compared to patients with a low score. GO analysis showed that this 14-gene signature was significantly involved in defense response and Th1 cytokine production (FDR <0.05). KEGG pathway analysis was able to confirm a statistically significant involvement of these genes in JAK-STAT and TLR signaling. In this second phase of the project, we were able to find a gene signature for each disease with a significant prognostic value that could be useful in clinical practice, especially in early stages. Evidence of a strong involvement of JAK-STAT pathway in analysis of both MF and SS is interesting because this pathway is well known to be involved in CTCL pathogenesis and its pharmaceutical inhibition is still studied.
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DE, ACUTIS Laura. "Characterisation of different hop ecotypes (Humulus lupulus, L.) in Central Italy and evaluation of the biological activity of their extracts, EO and components against Sitophilus granarius (L.)." Doctoral thesis, Università degli studi del Molise, 2019. http://hdl.handle.net/11695/91436.

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L'uso indiscriminato di insetticidi sintetici per diversi decenni ha sollevato preoccupazioni per la salute umana, principalmente a causa del loro lento degrado nell'ambiente, dei residui tossici da essi rilasciati e dell'evoluzione della resistenza ai pesticidi nelle popolazioni di parassiti (Isman, 2006). I gravi problemi di resistenza agli insetticidi nei parassiti e la contaminazione della biosfera associata all'uso su larga scala di pesticidi sintetici, hanno portato alla ricerca di prodotti eco-compatibili con maggiore selettività. Questa consapevolezza ha creato un interesse mondiale nello sviluppo di strategie alternative, compresa la scoperta di nuovi insetticidi più ecologici rispetto alle sostanze chimiche sintetiche (Rajashekar et al.,2012a, b; Miresmailli e Isman, 2014). In questo contesto, l'impiego di insetticidi a base di estratti botanici sta suscitando un notevole interesse sia tra i ricercatori che tra i consumatori. È noto che vari composti vegetali si legano ad alcune macromolecole biologiche (principalmente proteine), interagendo con siti specifici all'interno delle cellule. Ultimamente, lo studio sulle interazioni tra sostanze naturali e componenti cellulari ha assunto un ruolo importante nello sviluppo di farmaci sintetici. Ciò potrebbe incoraggiare la ricerca verso l'identificazione di nuovi composti/estratti con attività biologica in quanto costituiscono la base per nuovi approcci biotecnologici alla difesa delle piante e alla loro gestione. Oltre alle nuove classi di insetticidi, sono però necessarie sostanze chimiche che presentano diverse modalità di azione, in modo da mantenere una produzione alimentare stabile (Gokce et al., 2012). La maggior parte delle piante si difende dagli erbivori attraverso la produzione di metaboliti secondari come terpeni, composti fenolici e composti contenenti azoto (Taiz and Zeiger, 2010). Alcuni di questi, tra cui piretrina e rotenone, provocano tossicità diretta, altri causano interruzioni fisiologiche (regolatori della crescita) ed altri ancora vengono utilizzati come repellenti, attrattivi o anti-nutrizionali (Isman, 1999; Gokce et al., 2006). Il luppolo (Humulus lupulus L.) è una pianta perenne e rampicante, utilizzata nei birrifici per aggiungere l’amaro e l’aroma alla birra (Chadwick et al., 2006) la cui produzione è stata stimata di oltre 100.000 tonnellate in tutto il mondo (FAOSTAT, 2014). Tuttavia, parti aeree di questa pianta, producono diversi composti secondari come resine amare, olio essenziale (OE), tannini e terpeni ed hanno dimostrato avere attività biologiche: xantumolo, il principale prenilflavonoide, è stato segnalato possedere effetti antitumorali e antiossidanti (Jacob et al., 2010; Colgate et al ., 2010); gli iso-α-acidi del luppolo influenzano positivamente il metabolismo del glucosio, l'obesità indotta dalla dieta e il relativo declino cognitivo nei roditori (Hiroaki Yajima et al., 2004; Miura et al., 2005; Yajima et al., 2005; Ayabe et al., 2018); i principali composti dell’ OE come α-umulene, β-mircene e β-cariofillene hanno mostrato attività antimicrobiche contro diversi ceppi di batteri Gram-positivi e Gram-negativi (Stompor e Zarowska, 2016). Inoltre, oltre agli impieghi in campo medico (Bocquet et al., 2018), l'interesse per gli estratti/composti derivati dal luppolo sta aumentando, alla luce di un loro possibile utilizzo anche nel controllo dei parassiti. In particolare, diversi articoli hanno evidenziato (Bocquet et al., 2018), attività antinutrizionale e repellente di estratti di luppolo e composti dell’OE di questa pianta (DeGrandi et al., 2012; Powell et al., 1997). Pertanto, nel presente studio l'attenzione è stata focalizzata sull’utilizzo di luppolo selvatico e sulla valutazione dell'attività biologica di estratti, OE e dei suoi principali composti (α-umulene, β-mircene e β-cariofillene) contro il tonchio del grano Sitophilus granarius (L.) (Coleoptera Dryophthoridae). Successivamente, l'attenzione è stata focalizzata sulla caratterizzazione degli ecotipi di luppolo in diverse località dell'Italia centrale (Abruzzo e Molise) al fine di individuarne il migliore in termini di contenuto in polifenoli, associato ad un elevato potere antiossidante. I terpeni, α-umulene, β-mircene e β-cariofillene sono risultati i componenti principali (77,6%) dell’OE. Tra tutti i composti chimici e gli estratti testati, l'OE è stato in grado di esercitare la massima tossicità di contatto con valori di LD50 e LD90 di 13,30 e 40,23 μg/adulto dopo 24 ore dall'applicazione, diminuendo a 11,77 e 36,80 μg/adulto dopo 48 ore, rispettivamente. Tra gli estratti in solvente il più attivo è stato quello in acetone, mentre tra i composti la maggiore tossicità da contatto è stata riscontrata per l'α-umulene. Inoltre, l’α-humulene ha mostrato il miglior indice di repellenza (IR) (-38,89) contro gli adulti di S. granarius. Per quanto riguarda la tossicità per inalazione, la massima attività fumigante è stata osservata per il ß-mircene con valori di LC50 e LC90 di 72,78 e 116,92 mg/L in assenza di grano e 115,78 e 171,42 mg/L in presenza di esso. La massima mortalità per ingestione è stata rilevata nell'estratto in acetone, mentre la maggiore deterrenza per l'estratto in metanolo. L'attività anticolinesterasica è risultata trascurabile per tutte le sostanze, con la sola eccezione del ß-cariofillene, che ha mostrato un effetto inibitorio dose-dipendente, ad eccezione, invece, tutte le frazioni libere di polifenoli che hanno mostrato una buona attività anticolinesterasica. Il più alto contenuto in polifenoli è stato trovato nell’ecotipo raccolto nelle “99 Cannelle” (78,28 mg/g di peso secco) associato alla migliore attività anticolinesterasica. Infine, il contenuto più elevato in alfa e beta acidi è stato registrato nel campione raccolto in “Bussi”. Questo studio indica che il luppolo selvatico potrebbe rappresentare una fonte di sostanze biologicamente attive verso adulti di S. granarius, in quanto ha mostrato una buona tossicità per contatto, ingestione e inalazione, da utilizzare anche come repellente a basso costo ed eco-compatibile nella protezione degli alimenti conservati. Inoltre, i risultati confermano che gli ecotipi di luppolo esaminati mostrano differenze significative nel contenuto in polifenoli, che determinano diverse attività antiossidanti e anti-colinesterasiche. Quest'ultime, in particolare, potrebbero essere responsabili dell'azione insetticida riscontrata precedentemente negli estratti alcolici di alcuni ecotipi. Questi risultati evidenziano, per cui, la necessità di definire la composizione chimica delle varie frazioni al fine di caratterizzare i diversi ecotipi e identificare le molecole biologicamente attive.
The indiscriminate use of synthetic insecticides for several decades has raised long-term human health and environmental concerns, mainly due to their slow degradation in the environment and toxic residues in the products, as well as the evolution of resistance to pesticides in pest populations (Isman, 2006). The serious problems of insecticide resistance in pests and the contamination of the biosphere associated with large scale use of synthetic pesticides have led to the search for eco-friendly pesticides with greater selectivity to the pests. This awareness has created a worldwide interest in the development of alternative strategies, including the discovery of newer insecticides that are more environmentally friendly than synthetic chemicals (Rajashekar et al., 2012a, b; Miresmailli and Isman 2014). In this context, the use of insecticides based on botanical extracts is attracting considerable interest among both researchers and consumers. It’s known that various plant compounds bind to some biological macromolecules (mainly proteins), interacting with specific sites inside the cells. Lately, the study on the interactions among natural substances and cellular components has assumed an important role in the development of synthetic medicines/drugs/compounds. This could encourage the identification of new plant compounds/extracts with biological activity since they constitute the basis for new biotechnological approaches to plant defense and its management. Therefore, in addition to new classes of insecticides, chemicals that have different modes of action are needed to maintain stable food production (Gokce et al., 2012). Most plants defend themselves from herbivory through production of secondary compounds such as terpenes, phenolics and nitrogen-containing compounds (Taiz and Zeiger, 2010). Some of these secondary compounds, including pyrethrin and rotenone, produce direct toxicity, while others cause either physiological disruption as caused by growth regulators or behavioral effects as repellents, attractants or antifeedants (Isman, 1999; Gokce et al., 2006). Hop (Humulus lupulus L.) is a high-climbing, perennial vine, utilized in the brewing industry to add flavor and bitterness to beer (Chadwick et al., 2006) whose production has been estimated at over 100.000 tons worldwide (FAOSTAT, 2014). However, aerial parts of this plant produces several secondary metabolites as bitter resins, essential oil (EO), tannins and terpenes, proved to have biological activities: xanthohumol was reported to show anticancer and antioxidant effects (Colgate et al., 2010); hop iso-α-acids positively affect glucose metabolism, diet-induced obesity and its relative cognitive decline in rodents (Miura et al., 2005; Yajima et al., 2005; Ayabe et al. 2018); main compounds of EO such as α-humulene, α-myrcene and β-caryophyllene showed antimicrobial activities against different strains of Gram-positive and Gram-negative bacteria (Stompor and Zarowska 2016). Moreover, besides medical purposes (Bocquet et al., 2018a), the interest in hop extracts/compounds is increasing in the light of a their possible use also in pest control (Bocquet et al., 2018b). In particular, several papers highlighted activities against insect due to both antifeedant and repellent activities for hop extracts or EO compounds of this plant (DeGrandi et al 2012; Powell et al 1997). Aim of the present study is to gain a further insight into wild hop properties. Thus, in a first part the biological activity of …hop extracts, EO and its principal chemical compounds (α-humulene, α-myrcene and β-caryophyllene) against the granary weevil Sitophilus granarius (L.) (Coleoptera Dryophthoridae) was investigated;subsequently, the attention was focused on the characterization of hop ecotypes in different locations of Central Italy (Abruzzo, Molise) in order to identify the best one in terms of polyphenols content associated with a high antioxidant power . The terpenes, α-humulene, β-myrcene and β-caryophyllene were the main components (77.6%) of EO. Among all chemical compounds and extracts tested, EO was able to exert the highest contact toxicity with LD50 and LD90 values of 13.30 and 40.23 µg/adult after 24 h of application, decreasing to 11.77 and 36.80 µg/adult after 48 h, respectively. Between solvent extracts the most active was the one in acetone while among compounds the greatest contact toxicity was observed for α-humulene. Moreover, α-humulene was able to exert the highest average RI (-38.89) against S. granarius adults. As regards to inhalation toxicity, the highest fumigant activity was observed for ß-myrcene with LC50 and LC90 values of 72.78 and 116.92 mg/L in the absence of grain, and 115.78 and 171.42 mg/L in the presence of it. The highest ingestion mortality was detected in acetone extract while the greatest deterrence was found for methanol extract. Negligible anticholinesterase activity was found for all substances in the checked range, with the only exception of ß-caryophyllene which showed a dose dependent inhibitory effect, whereas all free fractions of polyphenols showed anticholinesterase activity. The highest polyphenols content was found for the ecotype collected in 99 Cannelle (78.28 mg/g of dry weight) associated with the highest anticholinesterase activity. Finally, the highest content of alpha and beta acids was recorded in the sample collected in Bussi. This study indicate that wild hop is a source of biological substances which are active on S. granarius adults by contact, ingestion and fumigant toxicity, to be also utilized as low-cost, eco-friendly pests repellents in the protection of stored food. Moreover, the results confirm that the examined hop ecotypes show significant differences in the content of polyphenols, which determine different antioxidant and anti-cholinesterase activities. The latter, in particular, could be responsible for the insecticidal action found previously in alcoholic extracts of ecotypes. These results highlight the need to define the chemical composition of the various fractions in order to characterize the various ecotypes and identify the biologically active molecules.
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PIAI, ANNA. "Diagnostic performance and organ dose evaluation in radiological diagnosis and follow-up of Ollier enchondromatosis pediatric patients: a phantom study." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/883102.

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The European Council Directive 2013/59/Euratom included pediatric exposure in the special practices for which appropriate medical radiological equipment and practical techniques have to be ensured. Children are generally more sensitive to X-rays than adults, mainly due to rapid cell growth and replication, and a longer lifespan after exposure. Hence, the optimization of protection is a priority factor and it shall involve all the practical aspects of medical radiological procedures, from the selection of equipment to quality assurance and the assessment of patient doses. These concepts are strongly endorsed by health care organizations dedicated to providing safe and high-quality pediatric imaging, particularly in modalities involving higher radiation doses, such as computed tomography and fluoroscopy. IRCCS Istituto Ortopedico Galeazzi is a reference center for the diagnosis and treatment of pediatric orthopedic and traumatological diseases, including orthopedic tumors. Ollier disease is a rare skeletal disorder characterized by the presence of multiple enchondromas, which are intraosseous, usually benign, cartilage tumors. Although the enchondromas start out as benign, they may become malignant, so children affected by the disease undergo multiple radiographs over time. Special effort is thus required to reduce the risk of radiation-induced cancers, and the benefit provided by radiological procedures has to be properly balanced with the health risk associated with ionizing radiation. The principal aim of this study was to evaluate the applicability of a relatively novel low-dose technique based on a slot scanning technology (EOS imaging system), for the diagnosis and follow-up of Ollier disease. For this purpose, a 5-year-old anthropomorphic phantom was specifically purchased to evaluate the diagnostic and dosimetric performances of the system. Digital radiography (DR) and computed tomography (CT), the current gold standards for diagnosis and monitoring, were evaluated for comparison. Ollier enchondromas were simulated with homemade bone structures stuck on the phantom, which was then imaged with DR, CT, and the EOS system at three different scanning speeds. To assess the diagnostic power of the imaging system, non-expert observers and experienced radiologists measured the inserts dimensions and compared them with those derived from CT and DR. Interobserver and intermodality reproducibilities were evaluated through Bland-Altman analysis. Furthermore, the accuracy in the size estimation was investigated by comparing the measured dimensions with the real ones. Dosimetric evaluations were performed for each imaging technique through Monte Carlo (MC) simulations and in-phantom measurements with thermoluminescent dosimeters (TLDs). The validation of MC simulations with TL dosimetry was necessary for the EOS system as no reference was found in the literature. Three speed levels of the EOS X-ray tube, and two DR acquisition protocols, respectively suited for diagnosis and follow-up, were investigated. The measured organ doses were used to calculate effective dose according to the ICRP 103 recommendations. Risks of radiation-induced cancers were estimated in the form of Lifetime Attributable Risk (LAR). The EOS system performed similarly to DR and CT in both detection and measurement of enchondromas-like inserts. Excellent intermodality reliability and interobserver reproducibility were obtained for each imaging technique. EOS fast protocol provided a reduction of effective and organ doses with respect to DR acquisitions performed with the diagnostic protocol. When the DR protocol optimized for follow-up was considered, instead, no significant dose sparing was observed, neither in organ doses nor in effective dose. CT doses were considerably higher than doses of EOS and DR, regardless of the acquisition protocol or speed level. Comparable LARs were observed for EOS acquisitions performed with the fast protocol and DR examinations with the follow-up protocol. DR diagnosis protocol was found to be equivalent, in terms of radiological risk, to the EOS intermediate speed level. The risk associated with CT examinations was two orders of magnitude higher than of the other techniques. This work showed that the EOS system has the same diagnostic capability as DR and CT to detect and measure enchondromas-like inserts in a pediatric phantom, but delivering lower doses. Although no dose reduction was found with respect to DR follow-up protocol, EOS fast protocol still provides low doses, and the two techniques were found to be equivalent in terms of LAR. Thus, it may be considered a valid solution for both the diagnosis and followup of patients with Ollier disease or other bone pathologies, allowing easier and faster exams, which is a crucial aspect in pediatric applications.
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48

MAGOGA, GIULIA. "MOLECULAR IDENTIFICATION AND DELIMITATION OF INSECT TAXA: DEVELOPMENT OF NEW DATA, APPROACHES AND EVALUATION OF TOOLS EFFICIENCY." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/702867.

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Molecular taxonomy is the science that classifies and identifies organism basing on molecular information. Its application to species-rich groups of organisms, as insects, could improve and accelerate taxa identification and delimitation. The efficiency and the limits of the methods for molecular taxonomy have to be properly evaluated for achieving unbiased results with this taxonomic approach. The main aims of this thesis are: i) to develop COI barcode libraries for Euro-Mediterranean Chrysomelidae identification and test DNA-barcoding efficiency in the identification of the species of the family; ii) to estimate group-specific nucleotide distance thresholds for the molecular identification of Chrysomelidae taxa and compare the error related to their use with the error related to the use of a general threshold value estimated for the whole family; iii) to apply molecular species delimitation methods to other insects taxa with the aim of resolving their taxonomic status in an integrative taxonomy framework; vi) to test the influence of factors intrinsic to the analysed data on molecular species delimitation efficiency. The results obtained confirmed the high efficiency of DNA-Barcoding as tool for Chrysomelidae molecular identification (94-99% efficiency) and the usefulness of molecular delimitation methods in integrative taxonomy for resolving taxonomic debated issues. The use of groups specific thresholds resulted to be related to a significantly lower identification error than the use of a general threshold for the whole Chrysomelidae, suggesting how the use of fixed thresholds for taxa identification is unwise. Finally, some factors, i.e. the species delimitation methods used, the geographic intraspecific distance among individuals collection localities and the difficulties in morphological identification of species, resulted to affect the efficiency of molecular species delimitation.
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49

CALCINA, SERGIO VINCENZO. "Ambient vibration measurements for non-destructive evaluation of structures by means of seismic methods and ground-based microwave interferometry." Doctoral thesis, Università degli Studi di Cagliari, 2015. http://hdl.handle.net/11584/266845.

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This thesis collects the results of the researches carried out during the Ph.D. course in “Technologies for the Conservation of Architectural and Environmental Heritage” into the School of Civil Engineering and Architecture of the University of Cagliari. The main topics of this research are focused on the experimental dynamic analysis of the structures with prevalent, but not exclusive, interest for the analyses of historic structures. The research deals with several issues concerning both the experimental measurements and the relationships between vibration properties and structural features and materials. The study starts with an introduction, developed into the first chapter, where the general principles of the experimental dynamic analysis methods of structures are presented and summarised, especially for the passive techniques based only on ambient vibrations records. The next chapter presents and describes the main features of the Ground-based Radar Interferometry to perform remote measurements of vibrations, using the phase difference between reflected signals coming from the surface of the same object inside the radar scenario. This technique has been developed in relatively recent years and has seen a considerable spread thanks to the short time need for the measurements and for the capability to retrieve reliable time series of displacement without any contact sensors above the structures. Furthermore the vibration data, acquired with both conventional systems (such as seismic sensors, velocimeters, accelerometers, etc.) and the microwave interferometer IBIS-S (Image By Intereferometry Survey), have been compared. Different case studies have been examined and critically discussed in the following chapters. In particular, chapter three is focused on the analysis of the vibration properties of an earthquake damaged bell tower located near the epicenter of the Emilia earthquake. Both ex ante and ex post conditions respect to the seismic induced damage have been compared. For this purpose a non-contact dynamic survey has been carried out by means of the radar interferometry method. The campaign of measurements has been conducted after the earthquake to describe the dynamic behaviour of the structure with open fractures pattern and with significant structural damages. Finally, a Finite Element model of the structure has been done in order to compare the actual dynamic response of the tower with that one of the undamaged structure. Chapter four looks at the influence of the vibration artificially induced by the coordinated movement of twenty people to improve main dynamic properties identification of the structure. In this case, the measurements have been carried out using the radar sensor by means of four stations located around the examined structure, the Leaning Tower of Pisa. The measurements have been performed in both operational mode using only wind induced vibrations and also with the artificial human forcing, applied at the top floor of the tower. Chapter five describes both the experimental measurements and the numerical modelling carried out in order to derive the dynamic features of two similar bell towers. The comparison between the dynamic behaviour of the towers is aimed at studying the influence of the mechanical properties of different construction materials. In fact, the towers are symmetrically built on both sides of the main façade of a church but the two structures are made using different materials and with different construction techniques. The oldest tower is a stone masonry building and the second one is a Reinforced Concrete structure. In this case, the analyses have been carried out using vibration data acquired by means of both available systems, i.e. the IBIS-S radar interferometer for the 2 measurements related to the upper parts of the structure (not easily accessible) and some seismic transducers for the stations located inside of the building. Chapter six finally presents the vibration measurements performed on a double curvature arch dam with different reservoir water level in order to analyse the variation of the linear dynamic response of the structure related to the water level height on the upstream side of the dam. The experimental surveys are described and the comparison with a numerical modelling is shown.
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50

TORINO, Valentina. "Evaluation of proline increase in plant parts stimulated by cadmium and detected by honey bee as environmental indicator." Doctoral thesis, Università degli studi del Molise, 2022. https://hdl.handle.net/11695/114588.

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Negli ultimi 50 anni l'aumento esponenziale dell'inquinamento, compreso quello da metalli pesanti, come il cadmio (Cd), ha portato a numerose alterazioni che coinvolgono varie specie animali, come la preoccupante diminuzione di api, insetto pronubo per eccellenza. A causa della loro immobilità, le piante devono affrontare costantemente vari stress (sia abiotici che biotici) sfruttando la loro capacità di adattamento ai cambiamenti ambientali. È stato dimostrato che nei periodi di stress (idrico, da metalli pesanti ecc.) si attivano meccanismi di protezione mediati dalla prolina, che hanno un’azione scavenger. Gli aminoacidi sono sempre presenti nel nettare delle angiosperme, e la prolina rappresenta il 70% degli aminoacidi pollinici. Gli aminoacidi liberi possono agire da potenti attrattivi per gli insetti e in particolare per le api. La prolina, infatti, è l'amminoacido più abbondante nell'emolinfa di molte specie, compreso le api. Queste evidenze suggeriscono un rapporto evolutivo api-prolina. Oltre al sistema fiorale, anche le foglie, attraverso l'emissione di sostanze volatili (VOCs), possono svolgere un ruolo importante nel processo di attrazione o repellenza degli insetti. La complessità della comunicazione pianta-insetto mediata dai VOCs, basata sui sofisticati meccanismi di percezione degli insetti, e sulle loro risposte comportamentali, deve ancora essere completamente chiarito. Lo scopo di questo lavoro è stato quello di mostrare se l'aumento della prolina ed il cambiamento del patter dei VOCs, indotto dalla contaminazione da Cd, possa influenzare la capacità delle api di percepire le piante inquinate. Per perseguire questo scopo sono state utilizzate tecniche analitiche come HPLC, GC.MS, PTR-qTOF e ICP, oltre a biosaggi come un test di alimentazione delle api e registrazioni EAG. Il lavoro è stato condotto su Medicago sativa L. coltivata su substrato inquinato con Cd (10 - 20ppm), ed è stato confermato l’aumento della prolina. Le analisi dei VOCs hanno mostrato che i cambiamenti maggiori, in termini di metabolismo secondario, avvenivano principalmente a livello dei tessuti fogliari, con un maggior aumento dell’emissione di VOCs rispetto ai fiori. I risultati EAG hanno permesso di ipotizzare una preferenza delle api per le piante inquinate. Tuttavia il biosaggio ha mostrato che 3.2 mMol, in un intervallo da 0 a 6.4, è la concentrazione a cui corrisponde la maggiore quantità di nettare bottinato, generando un profilo gaussiano tra la quantità di nutrimento assunta e la concentrazione di prolina. Questa risposta si presta a due possibili interpretazioni; la prolina ad alta concentrazione nel nettare genera: 1) un effetto repellente che induce le api ad interrompere l’alimentazione 2) una saturazione metabolica sia in termini bioenergetici che di sostanze azotorganiche. Sono necessari ulteriori studi per chiarire questo aspetto cruciale, poiché solo nel primo caso le api evitano del tutto di nutrirsi di piante inquinate e, di conseguenza: a) non produrranno miele e altri prodotti dell’alvere inquinati, b) questo comportamento non limita l’adozione di tecniche di fitodepurazione dei terreni inquinati da cadmio.
In the last 50 years the exponential increase in pollution, including heavy metals, such as cadmium (Cd), has led to numerous alterations involving various animal species, such as the worrisome decrease of honeybees, the pollinating insects par excellence. Because of their immobility, plants must constantly face various stresses (both abiotic and biotic) exploiting their ability to adapt to environmental changes. It has been demonstrated that proline-mediated protection mechanisms, with scavenger actions, are activated under stress (water, heavy metal etc.) conditions. Amino acids are always present in the nectar of angiosperms, and proline represents 70% of pollen aminoacids. Free amino acids can be strong attractants for insects, in particular for bees, that are able to recognize proline taste. Indeed proline is particularly important for insects, so as to be the most abundant aminoacid in the hemolymph of many of them, including bees. These evidences suggest a bees-proline evolutionary relationship. In addition to the flowers, also the leaves, through the emission of volatile organic compounds (VOCs), can play an important role in the process of attraction or repulsion of insects. The complexity of plant-insect communication via VOCs, based on the sophisticated perception mechanisms of insects, and their behavioral responses, have yet to be fully elucidated. The aim of this work was to show whether the proline increase and the VOCs pattern change, induced by Cd contamination, could influence the ability of bees to perceive the polluted plants. To achieve this purpose analytical techniques like HPLC, GC-MS, PTR-qTOF and ICP have been used, as well as bioassays like honeybees feed test and EAG recordings. The work was conducted on Medicago sativa L. plants grown on polluted substrate with Cd (10 and 20 ppm), and the proline increase was confirmed. The VOCs analyses showed that the major changes, in terms of secondary metabolism, took place mainly at leaf tissues, with a higher increase in VOCs, respect to the flowers. The EAG results allowed to speculate a preference of the honeybee towards polluted plants. However the feed test showed that 3.2 mMol, in a range from 0 to 6.4, is the concentration to which it corresponds the major quantity of foraged nectar, thus generating a gaussian profile between the quantity of nutrient solution taken and the proline concentration. This response lends itself to two interpretations; the proline at high concentration in the nectar generates: 1) a repellent threshold that leads the bees to stop feeding or 2) a metabolic saturation both in bioenergetics terms and azotorganic substances. Further studies will be needed to clarify this crucial aspect because only in the first case bees will completely avoid feeding on polluted plants and, consequently: a) they will not produce polluted honey and other beehive products, b) such behaviour will not limit the adoption of phytodepuration techniques of soils polluted with cadmium.
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