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Semwogerere, Denis Bbija. "Wave Number Selection and Defect Dynamics in Patterns with Hexagonal Symmetry." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/5300.
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Wave Number Selection and Defect Dynamics in
Patterns with Hexagonal Symmetry
Denis B. Semwogerere
108 Pages
Directed by Dr. Michael F. Schatz
We report quantitative measurements of wave number selection, secondary instability and defect dynamics in hexagonal patterns. A novel optical technique ("thermal laser writing") is used to imprint initial patterns with selected characteristics in a B뮡rd-Marangoni convection experiment. Initial patterns of ideal hexagons are imposed to determine the band of stable-pattern wave numbers. For small values of control parameter epsilon the measured stable band is found to agree quantitatively with theoretical predictions at the low-wave-number side of the band, and qualitatively at the high-wave-number side. Long-wavelength perturbations of ideal hexagonal patterns suggested by theory are imposed for epsilon=0.46 and their growth rates are measured to investigate the mechanisms of secondary instability. Our results suggest a transverse-phase instability limits stable hexagons at low wave number while a longitudinal-phase instability limits high-wave-number hexagons. Initial patterns containing an isolated penta-hepta defect are imprinted to study defect propagation directions and velocities. The experimental results agree well with theoretical predictions. The experimental investigations are discussed in the context of patterns with hexagonal symmetry formed under nonequilibrium external driving conditions.
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Руденко, Александр Антонович. "Вероятностные модели и методы оценивания надежности программных средств с учетом вторичных дефектов." Thesis, Полтавский национальный технический университет им. Ю. Кондратюка, 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19065.
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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.13.06 – информационные технологии – Национальный технический университет "Харьковский политехнический институт", Харьков, 2015.
Диссертация посвящена разработке моделей, методов оценки надежности программно-технических комплексов, информационной технологии на основе
учета внесения вторичных дефектов. Как показывает проведенный анализ, необходимость обеспечения точности оценки надежности программного обеспечения обуславливает актуальность научных исследований, посвященных разработке и совершенствованию методов и моделей оценки. В существующих моделях оценки надежности не учитывается фактор вторичных дефектов или этому аспекту не уделяется внимание вообще. Это может привести, с одной стороны, к неэффективному применению и распределению методов и средств повышения надежности, а с другой, к недооценке рисков, связанных с возникновением отказов. Усовершенствованы вероятностные модели оценки надежности программных средств на основе учета параметров вторичных дефектов, путем модификаций функций риска этих моделей, что позволяет адекватно отображать процессы тестирования и сопровождения программных средств. В рамках исследования был проведен анализ классификаций моделей, анализ вероятностных моделей повышения надежности на предмет возможности их модификаций с тем, чтобы учитывать вторичные дефекты. Наиболее целесообразно в контексте поставленной задачи использовать модель Джелински-Моранды. Разработан метод оценивания числа вторичных дефектов программных средств, основанный на анализе статистических данных проявления первичных дефектов программных средств, что позволяет повысить точность количественных оценок эксплуатационных показателей. Потребность в разработке метода вызвана трудностями аналитического нахождения вторичных дефектов на основе моделей оценки надежности программных средств. В методе оценивания числа вторичных дефектов по статистическим данным выявления дефектов учитываются факторы раннего и поздних этапов тестирования (эксплуатации), что соответствует реалиям соответствующих этапов жизненного цикла программ.The dissertation on obtaining the scientific degree of candidate of technical sciences in the specialty 05.13.06 – information technologies – National technical University "Kharkiv Polytechnic Institute", Kharkov, 2015. The dissertation dedicated to the developing of models, methods of reliability estimation of software-technical complexes of information technology on the basis of making secondary defects. Scientific results are: improving probabilistic models of reliability estimation of software based on the parameters of secondary defects by modifying the risk function of these models that allows to reflect processes of testing and maintenance of software; method of estimating secondary defects of software tools that is based on the analysis of statistical data of manifestation of primary defects of software tools that allows to raise the accuracy of the quantitative assessment of performance indicators; the method of calculating the average intensity of manifestation of defects and the average change in the intensity of manifestation of defects with the help of modified model Jelinski-Moranda that, unlike existing, takes into account factor of secondary defects that allows to verify the reliability of software tools. Information technology of assessment the secure of software tools taking into account the secondary defects is devised basing on the method of estimating the number of secondary defects according to the statistics of defect detection and the method of calculating the average intensity of manifestation of defects and the average change in the intensity of manifestation of defects. The proposed models and methods allow to raise the accuracy of estimation of reliability of software and hardware complexes that is achieved by taking into account the factor of secondary defects.
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Руденко, Олександр Антонович. "Імовірнісні моделі та методи оцінювання надійності програмних засобів з урахуванням вторинних дефектів." Thesis, ТОВ "Фірма "Техсервіс", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19064.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.06 – інформаційні технології – Національний технічний університет "Харківський політехнічний інститут", Харків, 2015.
Дисертація присвячена розробці моделей, методів оцінювання надійності програмно-технічних комплексів, інформаційної технології на основі врахування внесення вторинних дефектів. Науковими результатами є: удосконалення імовірнісних моделей оцінки надійності програмних засобів на основі врахування параметрів вторинних дефектів шляхом модифікації функцій ризику цих моделей, що дозволяє адекватно відображати процеси тестування і супроводу програмних засобів; метод оцінювання числа вторинних дефектів програмних засобів, що ґрунтується на аналізі статистичних даних прояву первинних дефектів програмних засобів, що дозволяє підвищити точність оцінок кількісних експлуатаційних показників; метод обчислення середньої інтенсивності прояву дефектів і середньої зміни інтенсивності прояву дефектів за допомогою модифікованої моделі Джелінські-Моранди, у якому, на відміну від існуючих, враховується фактор вторинних дефектів, що дозволяє верифікувати показники надійності програмних засобів. На основі методу оцінювання числа вторинних дефектів за статистичними даними виявлення дефектів та методу обчислення середньої інтенсивності прояву дефектів і середньої зміни інтенсивності прояву дефектів розроблена інформаційна технологія оцінювання надійності програмних засобів з урахуванням вторинних дефектів. Запропоновані моделі і методи дозволяють підвищити точність оцінювання надійності програмно-технічних комплексів, що досягається за рахунок урахування фактора вторинних дефектів.The dissertation on obtaining the scientific degree of candidate of technical sciences in the specialty 05.13.06 – information technologies – National technical University "Kharkiv Polytechnic Institute", Kharkov, 2015. The dissertation dedicated to the developing of models, methods of reliability estimation of software-technical complexes of information technology on the basis of making secondary defects. Scientific results are: improving probabilistic models of reliability estimation of software based on the parameters of secondary defects by modifying the risk function of these models that allows to reflect processes of testing and maintenance of software; method of estimating secondary defects of software tools that is based on the analysis of statistical data of manifestation of primary defects of software tools that allows to raise the accuracy of the quantitative assessment of performance indicators; the method of calculating the average intensity of manifestation of defects and the average change in the intensity of manifestation of defects with the help of modified model Jelinski-Moranda that, unlike existing, takes into account factor of secondary defects that allows to verify the reliability of software tools. Information technology of assessment the secure of software tools taking into account the secondary defects is devised basing on the method of estimating the number of secondary defects according to the statistics of defect detection and the method of calculating the average intensity of manifestation of defects and the average change in the intensity of manifestation of defects. The proposed models and methods allow to raise the accuracy of estimation of reliability of software and hardware complexes that is achieved by taking into account the factor of secondary defects.
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Clemente, Damião Inácio. "Estresse hídrico sobre caracteres morfofisiológicos e agronômicos em populações de milho." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7572.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
The occurrence of estimation periods has been provoking several activities, increasing corn area cultivated in Brazil is rainfed, and as losses in annual productivity due to drought are around 15% of the total yield potential. The objective of this study was to evaluate the effect of water deficit on agronomic traits and production components on maize (Zea mays L.) genotypes and to distinguish populations with greater tolerance to water stress. The study was carried out during the period 2015/2016, in the experimental area of the Federal University of Goiás - Jatobá Campus, located in the city of Jataí / Goiás. Twenty-four genotypes were studied, 12 of which were pollinated: CC1; CCV; CRE1; CRE2; CRE3; CRE1S; MPA; MPA1; TG2R; TG2RMV; NAPPMHG; CRV-02, 10 genotypes of commercial hybrid F2 generation: HSG1, HSG2, HSG4, HSG4, HSG5, HSG6, HSG7, HSG8, HSG9 and HSG10 and two testers: DKB390 (tolerant) and BRS1030 (sensitive). The experiment was conducted in randomized blocks (DBC), in a 2 x 24 factorial scheme, (2 planting times and 24 genotypes), with 4 reps. The traits are: Male and Female Flowering (FM and FF); Interval between female and male flowering in days (IFMF); Height of plants (APL); Ear Height (AES); Stay green (STG); Prolificity (PRL); Ear length (CES); Ear diameter (DES); Hectoliter weight (PHCL) and Grain yield (PGR). The genotypes CCV, CRE3 and TG2R are potential genotypes for use in breeding programs aiming at greater tolerance to water stress. These genotypes do not differ among themselves for PGR under water deficit, with productivity of 5.76; 6.26; 5.59 and 4.48 t ha-1, respectively. The flowering interval, ear diameter and stay green are good indicative as secondary traits in the selection of water stress tolerant genotypes.
A ocorrência de períodos de estiagem vem provocando diversas alterações nas estratégias agrícolas, Grande parte da área de milho cultivados no Brasil é de sequeiro, e as perdas em produtividade anual em decorrência da seca ficam em torno de 15% do potencial de rendimento total do milho. Deste modo, objetivou-se neste trabalho avaliar o efeito do déficit hídrico sobre caracteres agronômicos e componentes de produção em genótipos de milho (Zea mays L.) e distinguir populações com maior tolerância ao estresse hídrico. O estudo foi realizado durante o período de safra 2015/2016, na área experimental da Universidade Federal de Goiás - Campus Jatobá, situado na cidade de Jataí/Goiás, Foram estudados 24 genótipos, sendo 12 populações oriundas de polinização aberta: CC1; CCV; CRE1; CRE2; CRE3; CRE1S; MPA; MPA1; TG2R; TG2RMV; NAPPMHG; CRV-02, 10 genótipos de geração F2 de híbridos comerciais: HSG1, HSG2, HSG3, HSG4, HSG5, HSG6, HSG7, HSG8, HSG9 e HSG10 e duas testemunhas: DKB390 (tolerante) e BRS1030 (sensível). O experimento foi conduzido em blocos casualizados (DBC), em um esquema fatorial 2 x 24, (2 épocas de plantio e 24 genótipos), com 4 repetições. Os caracteres avaliados foram: Florescimento Masculino e Feminino (FM e FF); Intervalo entre os florescimentos feminino e masculino em dias (IFMF); Altura de plantas (APL); Altura de espiga (AES); Stay Green (STG); Prolificidade média (PRL); Comprimento de espiga (CES); Diâmetro de espiga (DES); Peso hectolitro (PHCL) e Produtividade de grãos (PGR). Os genótipos CCV, CRE3 e TG2R são potenciais genótipos para uso em programas de melhoramento visando maior tolerância ao estresse hídrico. Estes genótipos não se diferem entre si para PGR sob déficit hídrico, com produtividade média de 5,76; 6,26; 5,59 e 4,48 t ha-1, respectivamente. O intervalo de florescimento, diâmetro de espiga e stay green são bons indicativos como caracteres secundários na seleção de genótipos tolerantes ao estresse hídrico.
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Stevens, Troy A. "Classroom management techniques for ADHD students a teaching guide for secondary teachers /." [Denver, Colo.] : Regis University, 2009. http://adr.coalliance.org/codr/fez/view/codr:159.
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Caprariello, Andrew Vincent. "Cytoarchitectural Defects Secondary To Experimentally Induced Oligodendrocyte Death In The Adult And Developing Central Nervous System." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1346859526.
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Grynkewich, Magda Ann Urban 1952. "Elementary and secondary preservice educators' attitudes and knowledge about attention-deficit/hyperactivity disorder." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282128.
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General education teachers are largely responsible for the education of students with Attention-Deficit/Hyperactivity Disorder (ADHD). This is partially due to the educational movement toward inclusion for students with disabilities, and partially due to the ability of about 50% of students with ADHD to progress normally in school when given classroom accommodations and/or instructional modifications. General educators are teaching students with ADHD, yet limited information about teacher attitudes and knowledge about ADHD exists. This study is an initial exploratory investigation that examined the attitudes and knowledge about ADHD of preservice general education teachers at the elementary and secondary levels. Preservice elementary and secondary teachers completed an instrument designed to assess their attitudes and knowledge regarding ADHD. Two scales were created: one scale for items related to attitudes, and the second scale related to basic knowledge about ADHD. Research questions addressed preservice teachers' overall attitude and knowledge about ADHD, and whether grade level, gender, or perceived experience with ADHD influenced their attitude and/or knowledge about ADHD. Findings demonstrated that preservice teachers were in general agreement with positive attitude statements about ADHD. Differences in attitude ratings by grade level were significant, with elementary preservice teachers in stronger agreement with statements about ADHD than secondary preservice teachers. No significant differences in attitude were evident for gender. There was, however, a significant difference in attitude based on teachers' reported experience with ADHD. Teachers with basic or moderate/extensive experience had significantly more positive attitudes than teachers with no experience. Preservice teachers answered slightly more than half of the 11 knowledge items correctly. Elementary preservice teachers correctly answered more knowledge items about ADHD than secondary preservice teachers. No differences in knowledge were identified based on preservice teachers' gender or experience with ADHD. The findings are discussed in relation to other research on teacher attitudes and knowledge for ADHD. Implications for research and practice are discussed.
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Holmes, Henderson Arlene Victoria. "A defence of classical rhetoric in Scotland's Curriculum for Excellence." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4705/.
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This study warns that Scottish education is in danger of losing a valuable and venerable element of the school curriculum: the Classics. In order to demonstrate what Scottish education stands to lose, this study defends one particular element of the Classics, rhetoric, understood as the practice of effective speaking and effective writing for the purpose of persuasion. Scotland’s Curriculum for Excellence (CfE), first conceived in 2002 and implemented in 2010, is still a fledgling curricular initiative and schools are currently in an adjustment phase while existing syllabus content and pedagogical approaches are reviewed in order to better reflect the aims and purposes of the new curriculum. With increased focus on teacher autonomy, flexibility, personalisation and choice (Scottish Government 2008), now is an ideal time, I claim, to reveal and defend the contribution of rhetoric to this curriculum. This study promotes the learning and teaching of rhetoric in Scottish secondary schools, citing its potential to enrich not just the Classics but many areas of the curriculum, and makes particular claims for its contribution to cultivating critical and responsible citizens. Set against a broader backdrop of political and philosophical influences on curriculum reform and educational policy, this research examines the origins, aims and purposes of CfE and suggests that, although clearly influenced by supranational expectations regarding employability, economic growth and adequately equipping the future workforce, the curriculum appears to uphold the value of the Arts and Humanities and places education for citizenship at its core. These moves imply progress, at least in Scotland, towards ameliorating the ‘crisis in the Humanities’ and making room for increased focus on cross-curricular skills and abilities which are considered important for responsible citizenship: literacy, speaking and listening, argumentation and debate. The retention of Classical languages in Scotland’s new curriculum offers renewed hope, at least at the policy level, for the revitalisation of Classics teaching in Scottish schools. Yet despite their inclusion in the curriculum, they have received no promotion and there are no teacher training places available in Classical languages in Scotland so, at a practical level, the future of the subjects remains in crisis. By focussing on the educational merit of just one feature of the Classics, this study aims to highlight the value of rhetoric in CfE and in so doing raise the profile and improve the image of Classical language education. I argue that the Classical rhetorical framework, developed as a method for citizens to represent themselves effectively in public, has much to offer the development of literacy, critical literacy and critical thinking. These skills are shown to be linked to citizenship education and particular attention is paid to what is meant by ‘responsible citizenship’ in CfE. The argument is made that popular interpretations of the policy imply personally responsible or participatory conceptions of citizenship, but I promote a maximal interpretation in the form of ‘justice-oriented’ citizenship (Westheimer and Kahne 2004: 242). I defend that it is this conception of citizenship which is optimal for Scottish democracy both to appeal to the Scottish democratic intellect (Davie 1961) and to advance the values of wisdom, justice, compassion and integrity, the values inscribed on the mace in the Scottish Parliament (Gillies 2006). Despite ambiguity in CfE regarding the form of democracy envisaged for the 21st century, I argue that the study of rhetoric cultivates knowledge and skills which are particularly pertinent and beneficial to deliberative democracy and that in such a conception of democracy, rhetoric complements critical argumentation as a method of deliberation between citizens. I claim that it does so by facilitating narrative imagination, engaging the emotions and by providing a communicative bridge between diversely positioned deliberators. After highlighting and defending the value of rhetoric in CfE, the study concludes with the consideration of how rhetoric might best be positioned in the curriculum and advances a number of possible pedagogical models for its delivery, the most practical of which is offered by a cross-curricular approach but the most desirable of which is conferred by Classical languages.
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Bratt, Katharina. "Secondary plant metabolites as defence against herbivores and oxidative stress : Synthesis, isolation and biological evaluation." Doctoral thesis, Uppsala University, Department of Chemistry, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-1074.
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In this thesis the isolation, synthesis and biological evaluation of natural defense compounds against herbivores or oxidative stress is discussed.
The first part concerns the metabolites of platyphylloside ((5S)-5-hydroxy-1,7-bis-(4-hydroxyphenyl)-3-heptanone-5-O-β-D-glucopyranoside), a phenolic glucoside found in birch (Betula pendula) that possess digestibility inhibiting activity in herbivores. The structure-activity relationship of platyphylloside analogues were investigated regarding to stereochemistry and substitution pattern on the aromatic rings. The metabolites formed in vitro in rumen fluid were synthesized and the active metabolite determined as (R)-centrolobol (1,7-bis-(4-hydroxyphenyl)-3-heptanol). Treatment of mice and rats with rac-centrolobol did not effect either food intake or body weight. Effect of platyphylloside in moose was also investigated, and the results indicate that there was an in vivo digestibility reducing activity.
The second part concerns naturally occurring antioxidants. Avenanthramides is a class of phenolic antioxidants found in oat (Avena sativa). Avenanthramides derived from either anthranilic acid or 5-hydroxyanthranilic acid were evaluated for their antioxidative capacity and quantified in oat extracts. Avenanthramides derived from 5-hydroxyanthranilic acid possessed higher activity than those from anthranilic acid. The order of reactivity depending on substitution pattern on the phenolic moiety was found to be 4-hydroxy < 4-hydroxy-3-methoxy < 3,5-dimethoxy-4-hydroxy and 3,4-dihydroxy. A synthesis towards antioxidative compounds such as 4-deoxycarbazomycin was developed.
The third part concerns the isolation of compounds from Lodgepole pine (Pinus contorta) with antifeedant activity against pine weevil (Hylobius abietis). Two compounds possessing high activity were isolated and identified.
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Goodey, Nicole Ann. "Ecological patterns in plant defence chemistry and herbivore responses in natural populations of Brassica oleracea." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/21667.
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Relationships between two taxonomic kingdoms; plants and herbivorous insects, are hypothesized to be a major zone of interaction for generating current day biodiversity; and coevolutionary processes between these intricately linked organisms are hypothesized to maintain diversity in plant secondary chemistry. These metabolites play a key role in plant defence against herbivory and a high degree of intraspecific variation is observed at multiple ecological scales. However, the nature of selection maintaining variation in plant defence profiles is still a major question in evolutionary biology and ecology, and progress towards a deeper understanding is hampered by a lack of studies that take into account ecological context and the multivariate nature of plant defence phenotypes. In this thesis, I employ sophisticated chemical analysis techniques to identify a suite of glucosinolate secondary chemicals, representing different biosynthetic pathways, in the wild cabbage, Brassica oleracea, in natural populations in the UK. I used model-based cluster analysis to explore patterns of association between individual glucosinolates, predicting that as simultaneous resource allocation to multiple defences is likely to be constrained; negative associations between defensive traits should be observed. However, results revealed positive associations between glucosinolates. Therefore co-expression of multiple defences may not be costly for this species. Using this information in conjunction with herbivore surveys and experiments, I show that this mixture has the potential to shape patterns of herbivore abundance and host plant utilization: species-specific responses to variation in glucosinolate phenotypes are discovered at various ecological scales. Thus there is the potential for differential selection on plant chemotypes though species-specific attractions and aversions. By conducting fine scale experiments with herbivore species, I also found that glucosinolate variation has an impact on the counter-adaptations that some brassica specialists have evolved: in order to optimally defend against their own natural enemies, Brevicoryne brassicae aphids sequestering glucosinolates from their host plants must do so selectively, and must choose plants whose chemical profile best matches this behaviour. These findings show that glucosinolate profiles may be under natural selection by herbivores in wild populations, and that reciprocal evolution between these plants and their specialists may continue to promote diversity in secondary metabolites. Together these results highlight the complexity inherent in plant-insect interactions, the importance of field studies and generate a wealth of testable hypotheses for future work.
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Moeschberger, S. L. "A secondary analysis of the cognitive effects of methylphenidate and fenfluramine in children with mental retardation and hyperactivity." Online full text .pdf document, available to Fuller patrons only, 2000. http://www.tren.com.
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Keaveny, Dawn-Marie. "Transitioning from primary to secondary school in Jamaica : perspectives of students with learning disabilities and/or attention deficit hyperactivity disorder." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/7205/.
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This is a qualitative research with an ethnographic flavour. It seeks to understand the experiences and perspectives of a group of Jamaican students with learning disabilities (LD) and attention deficit hyperactivity disorder (ADHD) on their transitioning from primary to high school. At present, Jamaica does not have a transition policy and many students with disabilities transition to high school but are not receiving the level of support, and accommodations they need. Interviews were used in this research to gain an insider view of the students’ transition experiences. The students’ stories of high school were compared for similarities and differences using thematic analysis. Through inductive and deductive analysis their stories were examined and interpreted. Four general themes were identified as factors that influenced how students experienced school. These themes were pedagogy, ableist beliefs, the hidden curriculum and social networks. These themes were related to the theories of social capital and sense of belonging and it is argued that social capital and sense of belonging are likely to significantly impact students’ transition experiences, and future outcomes. The findings suggest students use their social capital in the form of social networks to navigate high school and access academic, emotional and social support. Belonging to a social network is associated with positive feelings towards school, as well as with a greater sense of connectedness to their school. Recommendations include the creation of a national transition policy to encourage a smooth transition of students from the primary to the secondary level of schooling. It is also suggested that teachers create opportunities for students to build social networks thereby increasing their social capital in schools. This research contributes to knowledge by presenting a Caribbean perspective on transition. It adds to the literature by giving voice to an often silent minority that is, Caribbean students with disabilities.
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Edmonds, Markus. "A Defence of Literary Theory : A psychoanalytical study of selected works by Percy Bysshe Shelley with a view to didactic usage." Thesis, Linnéuniversitetet, Institutionen för språk (SPR), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-61065.
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This essay argued the importance of literary theory in the classroom. As a teacher, it is possible to achieve the empathetic goals of the English curriculum and Judith A. Langer’s ambition of literate thinking by using poetry and literary theory in school. The essay demonstrated this with a Lacanian reading of Percy Bysshe Shelley’s poems “To a Skylark” and “Ode to the West Wind.” The analysis focused on readable and unreadable aspects of the poems. The readable aspects centred on the role of the Imaginary in “To a Skylark” and the representation of the fragmented body in “Ode to the West Wind.” Furthermore, the unreadable elements of the poetry demonstrated the discrepancy between the performative and declarative dimensions and the role of the pathetic fallacy in the signifying chain. Finally, this essay argued that, although all aspects of psychoanalytic literary theory should not be used in the classroom, elements of Lacanian thought can be used to combat the prevalence of individualism in Swedish upper secondary schools.
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Ewens, Vicki J. "An odontological study of ovicaprine herding strategies in the North Atlantic islands. The potential of dental enamel defects for identifying secondary product utilisation in an archaeological context." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5106.
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Abstract: Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.
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Pernica, Vítězslav. "Optimalizace výroby těžkých ocelových odlitků." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228645.
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Diploma thesis deal with definnig the casuses of stell castings defects in the DSB EURO s.r.o Foundry. The main target is to optimise technological parameters for avoiding the surface casting defects. The first stage is the identification of the defects, describing of the main reasons and mechanic. Defect quantification is make from measuring of area and volume of the mended defects. In association with surface defects, the number of the crackings was observed. Finally there are suggested correction actions based on the previous investigation.
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Ewens, Vicky Jane. "An odontological study of ovicaprine herding strategies in the North Atlantic islands : the potential of dental enamel defects for identifying secondary product utilisation in an archaeological context." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5106.
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Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.
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Müller, Mônica Anghinoni. "Influência de dinamizações de Mercurius solubilis em enzimas de defesa, crescimento da soja e no controle de Pratylenchus brachyurus." Universidade Estadual do Oeste do Paraná, 2015. http://tede.unioeste.br:8080/tede/handle/tede/1268.
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The nematode Pratylenchus brachyurus known as nematode lesions, affects the soybean crop caused significant damage, this means that there is a need to develop alternatives that supply the control of pathogens by aggregating in productivity. Then the objective is to verify the influence of homeopathic Mercurius solubilis in different potencies in soybean plants and on control of the nematode. For this, three experiments were carried out in climatized greenhouse, testing the potencies of 6, 12, 24, 50, 100, 200 and 400CH (centesimal Hahnemannian) of Mercurius solubilis, ethanol 30% and healthy plants (untreated and not inoculated) were used as control treatment. The treatments were applied weekly from the V3 growth stage of soybeans. Three days after the first treatment, inoculation of nematodes was done. After 50 and 70 days after inoculation of the first and second experiment respectively, were made assessments of the aerial part height, stem diameter, number of pods per plant, dry weight of aerial part, dry weight of leaf + petiole + stem, dry mass of total pods, dry weight per pod, fresh weight of root, and were count juvenile, adults and eggs in the soil and in roots, and determined the reproduction factor (RF). In the third experiment, were quantified enzymes involved in secondary metabolism of plants, peroxidase (POX), phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO). The sample of roots were taken at intervals of 0, 3, 7 and 14 days after treatment (DAT) and in the 3rd DAT, inoculation was made. In laboratory was conducted a experiment to evaluate in vitro motility and mortality, a distilled water solution containing 100 ml-1 juveniles and adults were placed in plastic container and add 7 mL of in vivo treatments tested at a dilution of 0.1%. The experiments were conducted in a randomized block design. The potencies 24CH, 50CH, 200CH and 100CH reduce the number of adults and juveniles in soil, as well as the reproduction factor, furthermore 100CH is able to interfere in the productive aspects, increasing 107.5% in the number of pods when compared to the control ethanol 30%, as well as dynamization 6CH and 12CH. To POX the enzymatic activity was higher for dynamizations 6CH, 100CH and 400CH, 3, 7 and 14 DAT respectively. The PAL activity presented increases of 79.93%, 80.72% and 84.10% in dynamizations 6CH, 12CH and 24CH respectively compared to control treatment, 3 DAT. 14 days after the first treatment, 400CH dynamization showed an increase in the enzymatic activity of 53.41% and 32.21% when compared to the control ethanol 30% and absolute control respectively. The dynamization 24CH when compared to absolute control showed an increase of 41.10% in the enzymatic activity. So Mercurius solubilis may be a potential alternative for the control of the nematode
O nematoide Pratylenchus brachyurus conhecido como nematoide das lesões, afeta a cultura da soja causado danos expressivos, isso faz com que haja a necessidade de desenvolver alternativas que supram o controle dos patógenos, agregando em produtividade. Objetivou-se então, verificar a influência do medicamento homeopático Mercurius solubilis em diferentes dinamizações nas plantas de soja e no controle de P. brachyurus. Para tanto, foram conduzidos três experimentos em casa de vegetação climatizada, testando-se as dinamizações de 6, 12, 24, 50, 100, 200 e 400CH (centesimal hahnemanniana) de Mercurius solubilis, Etanol 30% e plantas sadias (não tratada e não inoculada) foram utilizadas como tratamento testemunha. Os tratamentos foram aplicados semanalmente a partir do estádio fenológico V3 da soja. Três dias após o primeiro tratamento, foi feita a inoculação dos nematoides. Decorridos 50 e 70 dias após a inoculação do primeiro e segundo experimento respectivamente, foram realizadas as avaliações de altura de parte aérea, diâmetro do coleto, número de vagens por planta, massa seca de parte aérea, massa seca de folha+pecíolo+caule, massa seca total de vagens, massa seca por vagem, massa fresca de raiz, e contagem de juvenis, adultos e ovos presentes no solo e na raiz, e determinado o fator de reprodução (FR). No terceiro experimento, foram quantificadas enzimas envolvidas no metabolismo secundário das plantas, peroxidase (POX), fenilalanina amônia-liase (FAL) e a polifenoloxidase (PFO). As coletas das amostras de raízes foram realizadas no intervalo de 0, 3, 7 e 14 dias após o tratamento (DAT) sendo que no 3º DAT foi feita a inoculação. Em laboratório foi realizado experimento in vitro para avaliação de motilidade e mortalidade, uma solução de água destilada contendo 100 juvenis e adultos mL-1 foi depositada em recipiente plástico, e adicionados 7 mL dos tratamentos testados in vivo na diluição de 0,1%. Os experimentos foram conduzidos em delineamento em blocos casualizados. As dinamizações 24CH, 50CH, 100CH e 200CH reduzem o número de juvenis e adultos presentes no solo, assim como o fator de reprodução, além disso, a dinamização 100CH é capaz de interferir em aspectos produtivos pelo aumento de 107,5% no número de vagens quando comparada à testemunha etanol 30%, assim como a dinamização 6CH e 12CH. Para POX a atividade enzimática foi superior para as dinamizações 6CH, 100CH e 400CH, em 3, 7 e 14 DAT respectivamente. A atividade de FAL apresentou incrementos de 79,93%, 80,72% e 84,10% nas dinamizações 6CH, 12CH e 24CH respectivamente em relação à testemunha absoluta, 3 DAT. 14 dias após o primeiro tratamento, a dinamização 400CH mostrou um aumento na atividade enzimática de 53,41% e 32,21% quando comparada à testemunha etanol 30% e testemunha absoluta respectivamente. A dinamização 24CH quando comparada a testemunha absoluta mostrou um acréscimo de 41,10% na atividade enzimática. Assim Mercurius solubilis pode ser uma alternativa potencial para o controle de P. brachyurus
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Hedner, Erik. "Bioactive Compounds in the Chemical Defence of Marine Sponges : Structure-Activity Relationships and Pharmacological Targets." Doctoral thesis, Uppsala University, Division of Pharmacognosy, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8218.
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Marine invertebrates, in particular sponges, represent a source of a wide range of secondary metabolites, many of which have been attributed various defensive capabilities against environmental stress factors. In this thesis sponge-derived low-molecular peptide-like compounds and associated analogs are investigated for bioactivity and pharmacological targets.
The compound bromobenzisoxazolone barettin (cyclo[(6-bromo-8-(6-bromo-benzioxazol -3(1H)-one)-8-hydroxy)tryptophan)]arginine) was isolated from the sponge Geodia barretti and its ability to inhibit larval settlement of the barnacle Balanus improvisus was determined. With an EC50 value of 15 nM, this compound’s antifouling effect was higher than those of the previously reported brominated dipeptides from Geodia barretti, i.e., barettin and 8,9-dihydrobarettin; moreover, this antifouling effect was demonstrated to be reversible. However, the compound lacked affinity for 5-HT1-7 receptors, whereas barettin possessed specific affinity to 5-HT2A, 5-HT2C and 5-HT4, while 8,9-dihydrobarettin interacted with 5-HT4. In an attempt to evaluate structure-activity relationships synthesized analogs with barettin and dipodazine scaffolds were investigated for antifouling activity. The analog benso[g]dipodazine, with an EC50 value of 34 nM, displayed the highest settlement inhibition.
The studies of the structure-activity relationships of sponge-derived compounds were extended to cover analogs of agelasines and agelasimines originally isolated from sponges of the genus Agelas. Synthesized (+)-agelasine D and two structurally close analogs were investigated for cytotoxic and antibacterial activity. The profound cytotoxicity and broad spectrum antibacterial activity found prompted a further investigation of structure-activity relationships in 42 agelasine and agelasimine analogs and several characteristics that increased bioactivity were identified.
In conclusion this work has produced new results regarding the potent bioactivity of compounds derived from the sponges Geodia barretti and Agelas spp. and increased SAR knowledge of the fouling inhibition, cytotoxicity and antimicrobial activity of these compounds.
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Pöykkö, H. (Heikki). "Host range of lichenivorous moths with special reference to nutritional quality and chemical defence in lichens." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:951427959X.
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Abstract
Host use and range of herbivorous insects are determined by several factors, of which nutritional quality and secondary chemistry have been shown to play very important roles. For herbivores feeding on lichens these traits are assumed to be more critical than for species feeding on higher plants, since lichens are nutritionally poor and often contain high concentrations of secondary metabolites. I examined the role of lichens' nutritional quality and secondary chemicals on the performance of lichen-feeding Lepidopteran larvae. I also tested whether females of lichenivorous species preferably oviposit on host species of the highest nutritional quality for the growth of larvae.
Larvae of Eilema depressum performed best on Melanelia exasperata, which is of the highest nutritional quality, as indicated by the high N concentration and the absence of lichen secondary metabolites compared to the other lichens studied. Host nutritional quality did not promote the production of an additional generation. Larvae of E. depressum needed fewer instars and grew bigger on a high-quality diet than larvae reared on a diet of poorer quality. However, the main factor contributing to the wide variation in the number of larval instars was the question of whether or not larvae overwintered. Growth of Cleorodes lichenaria at the beginning of the larval period matched equally the nutritional quality of the hosts. However, the final larval period was shortest on Ramalina species, which was preferred by both females ovipositing their eggs and larvae searching for a host. In the field, larvae were found almost exclusively on Ramalina species.
Larvae of E. depressum were not able to survive on intact thalli of Vulpicida pinastri and Hypogymnia physodes, but after removal of lichen's secondary metabolites, larval survival remained equally high as on other lichens. Larvae also showed a clear preference towards thalli with lowered concentrations of secondary metabolites in Parmelia sulcata, V. pinastri and H. physodes. Parietin in Xanthoria parietina was the only secondary metabolite that had no impact on the survival or host selection of E. depressum larvae.
The present results show that the nutritional quality and some lichen secondary chemicals are important factors for the growth, survival and host selection of lichen-feeding Lepidopteran larvae. The preference-performance hypothesis is at least partly able to explain the host range of C. lichenaria, although it seems that there are also other factors, such as larval dispersal and host selection or top-down forces, that might contribute to host range of lichenivorous Lepidopteran larvae. Moreover, lichenivorous larvae seem to be partly responsible for their own host selection.
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Morris, Mary Ann. "A Comparison of Written Composition Assessment Using Standard Format Versus Alternate Format Among College-Bound Students with Learning Disabilities and/or Attention-Deficit/Hyperactivity Disorder." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5405/.
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The purpose of this study was to explore the efficacy of using a computer word processing program in the assessment of written expression with college-bound individuals who had been diagnosed with a learning disability (LD) and/or attention-deficit/hyperactivity disorder (ADHD). Fifty-six (35 eleventh and 21 twelfth) graders, attending a private college-preparatory school for students with LD and/or ADHD, were administered the Spontaneous Writing composite of the Test of Written Expression - Third Edition (TOWL-3). The TOWL-3 has equivalent forms, Form A and Form B. One form was administered in accordance with the test manual, using paper and pencil (standard format). The other form (i.e., alternate format) was administered with word processing access. Paired samples tests (repeated measure) and bivariate correlation designs were computed to explore the relationships between measures. Results of the study revealed significant increases (p<.01) in the subtest and composite scores when participants were administered the test in the alternate format. Other components of the research study did not reveal strong meaningful relationships when cognitive ability, graphomotor speed, and keyboarding rate were compared with the standard and/or alternative formats of the writing composite. A high rate of comorbity was exhibited with the majority of participants (75%) having two or more LD and/or ADHD diagnoses. On an informal questionnaire, the participants endorsed a strong preference for the use of word processors in the majority of their written academic tasks. The study concludes that for students who are accustomed to producing written work on a word processor, restriction from this writing tool can adversely affect the results of their product, leaving a false impression, underestimating their writing skills, ability, creativity, and subject knowledge. In addition, having access to a word processor during high stakes testing is paramount. Inaccurate results can affect future opportunities, such as admission to postsecondary educational settings. In summary, future and more extensive studies are needed to continue to increase the understanding of assessment, diagnosis, instruction, and assistive technology (AT) options for individuals with written language disorders.
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Shidonia, Fagarasan. "Alymphoplasia (aly)-type nuclear factor κB-inducing kinase (NIK) causes defects in secondary lymphoid tissue chemokine receptor signaling and homing of peritoneal cells to the gut-associated lymphatic tissue system." Kyoto University, 2000. http://hdl.handle.net/2433/151446.
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Guarracino, Sophia Elizabeth. "Students with Learning Disabilities and Attention Deficit Hyperactivity Disorder and Those Who Teach Them: Building Positive Relationships to Increase Academic Success." Bowling Green State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1273496818.
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Tavares, Sheila dos Santos. "Ecologia química da cana-de-açúcar: caracterização das respostas de defesa em diferentes cultivares de cana-de-açúcar." Universidade Federal de Alagoas, 2016. http://www.repositorio.ufal.br/handle/riufal/1638.
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Sugarcane plants (Saccharum sp) originates from Southeast Asia but has adapted to the climate and soil in Brazil thus become the main crop for ethanol and sugar production. The main obstacles in sugarcane production are pests and plant diseases. Amongst the various sugarcane pests, Diatrea saccharalis, are of great importance as they attack the sugarcane stalk. Upon attack, sugarcane plants combine constitutive and induced defenses in order to prevent further damage. Volatile organic compounds and secondary metabolites are two mechanisms synthetized by the plant that provides protection against herbivores. Based on the attributes, secondary metabolites have gained great interest as a tool for pest management. This study aims to identify volatile metabolites and metabolite alterations upon herbivore attack in different sugarcane cultivars in order to determine resistance. In addition, the effect of various chlorogenic acid doses on the different life stages of D. saccharalis was evaluated. Initially, two sugarcane cultivars were analyzed, SP81-3250 and SP89-1115, that are considered to be susceptible and resistant, respectively. These cultivars were acquired by the germplant bank of the Genetic Improvement Program of sugarcane at the Federal University of Viscosa (RIDESA). In addition, different material from the Saccharum Complex was used, including Saccharum officinarum, Saccharum officinarum (Caiana), Miscanthu and Erianthus, all acquired from EMBRAPA Tabuleiros Costeiros. The following behavioral assays were conducted: choice assays using wind tunnel, oviposition assays and larval performance when exposed to two plant cultivars (SP81-3250 and SP89-1115). Extraction and identification of phenolic compounds, DIMBOA and chlorogenic acid from SP81-3250 and SP89-1115 was conducted. Results from the no choice oviposition assay using D.saccaralis demonstrated a significant preference for oviposition on the SP89-1115 cultivar. There was a significant difference between the volatile profiles of the two different cultivars, which could explain the preference of D.saccaralis. The two cultivars also presented a quantitative difference of phenolic compounds present in both leaf and root tissue with and without infestation, chlorogenic acid was only detected in leaf tissue and at higher concentrations in the resistant cultivar. Feeding adult D. saccharalis with a diet containing chlorogenic acid resulted in deformation after emerging from the pupae. The various materials from the “Saccharum complex” presented a varied VOC profile. This study demonstrated that there is a difference between cultivars of sugarcane plants and their direct and indirect defense mechanisms. This provides a potential aspect that should be further explored within genetic programs of sugarcane and the development of resistant cultivars.A cana-de-açúcar (Saccharum sp.) é uma planta originária do sudeste da Ásia que adaptou-se bem ao clima e solo do Brasil, sendo a principal matéria-prima para a produção de etanol e açúcar. Um dos grandes entraves à produção de cana-de-açúcar ainda é o ataque de pragas e doenças. Dentre as pragas mais importantes para a cultura estão as que atacam o colmo e entre elas a broca-da-cana, Diatraea saccharalis. As plantas ao serem atacadas se protegem através da combinação de defesas constitutivas e induzidas que consequentemente, podem interromper a propagação do dano. Entre essas defesas está a síntese de compostos orgânicos voláteis (COVs) e a produção de metabólicos secundários tóxicos que lhes atribui proteção contra diferentes herbívoros. Este trabalho busca Identificar os metabólitos voláteis e as alterações metabólicas em diferentes cultivares de cana-de-açúcar que sejam induzidas em resposta a herbivoria, visando a busca de novas fontes de resistência. Além disso, avaliou-se o efeito de diferentes doses do ácido clorogênico sobre as diferentes fases do ciclo de vida de D. saccharalis. Primeiramente duas cultivares de cana-de-açucar foram analisadas SP81-3250 e SP89-1115 (consideradas resistente e suscetível, respectivamente). Estas foram adquiridas junto ao banco de germoplasma do Programa de Melhoramento Genético de cana-de-açúcar da Universidade Federal de Viçosa (RIDESA). Num segundo momento utilizaram-se diferentes materiais do “complexo Saccharum”, entre elas Saccharum officinarum, Saccharum officinarum (Caiana), Miscanthu e Erianthus que foram adquiridos junto a EMBRAPA Tabuleiros Costeiros. Foram realizados bioensaios de preferência em túnel de vento, comportamento de oviposição e performance larval, além de extração e identificação de compostos fenólicos, DIMBOA e ácido clorogênico nas duas cultivares SP81-3250 e SP89-1115. No teste de oviposição com chance de escolha D. saccharalis a mostrou preferência de oviposição para a cultivar suscetível SP89-1115. As diferenças encontradas entre os perfis dos COVs podem auxiliar a explicar este comportamento. As duas cultivares também apresentaram diferenças quantitativas e qualitativas nos compostos fenólicos presentes nos tecidos foliares e radiculares com e sem infestação, entre eles, o ácido clorogênico que foi detectado apenas no tecido foliar e em maior concentração na cultivar resistente. Quando adultos de D. saccharalis foram alimentados com dietas adicionadas de ácido clorogênico, estes apresentaram má formação após emergirem das pupas. Os diferentes materiais do “complexo Saccharum” apresentaram também diferenças nos perfil de COVs. Os resultados obtidos demonstram que diferentes cultivares de cana-de-açúcar possuem respostas de defesa direta e indireta distintas, apresentando-se como potencial a ser explorado e aplicado em Programas Genético de cana-de-açúcar no desenvolvimento de materiais mais resistentes.
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Pazinato, Daiane Maria Melo. "Capacidade antioxidante de Eugenia uniflora L. (Pintangueira) em resposta ao ambiente de mineração de calcário." Universidade Federal do Pampa, 2017. http://dspace.unipampa.edu.br:8080/jspui/handle/riu/3495.
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As condições ambientais podem influenciar a composição e produção dos metabólitos secundários, ocasionando maior ou menor capacidade antioxidante nas plantas. Em áreas de mineração ocorrem modificações no meio ambiente, alterações estas que podem vir a interferir nos constituintes do vegetal. Neste trabalho foi comparada a atividade antioxidante do extrato etanólico de Eugenia uniflora L. presente em área de mineração com uma área controle, bem como, foram feitas investigações da condição do meio ambiente. A atividade antioxidante foi analisada através de dois métodos: complexação do fosfomolibdênio e o método de sequestro de radicais livres DPPH° (2,2-difenil1-picril-hidrazila). Tendo em vista verificar a qualidade dos solos onde estavam as plantas, foi verificado o pH e investigada a presença de alguns elementos químicos. Na região de mineração não houve detecção de alguns elementos que são essenciais para a nutrição vegetal, são eles: cobre, molibdênio, níquel e zinco, assim como, ocorreu uma menor concentração de cobalto, que também é considerado um elemento essencial. A determinação do pH dos solos possibilitou definir o solo da área de mineração como básico (8,85±0,78), enquanto que o da área controle foi caracterizado como ácido (5,37±0,35). O valor de pH elevado na área de mineração é um fator que causa mais impactos na nutrição vegetal que a acidez do solo da área controle, pois a disponibilidade de nutrientes é afetada em maior proporção. As análises de água indicaram que a qualidade da água na área controle está adequada, enquanto que na área de mineração, os níveis de dureza, condutividade, cálcio e magnésio estavam elevados por se tratar de uma bacia de decantação de efluentes líquidos de fábrica de cal. A atividade antioxidante da planta localizada na área de mineração foi maior que a da planta da área controle, que não está sob influência de atividades de mineração. No método de complexo do fosfomolibdênio, a análise estatística demonstrou que entre os extratos de Eugenia uniflora L. das duas áreas analisadas não há diferença expressiva. No método de sequestro de radicais livres (DPPH) houve diferença significativa entre os distintos extratos. O maior percentual de atividade antioxidante observado foi de 96,55% para o extrato da área de mineração, enquanto que para a área controle foi 92,78%. Alguns fatores podem ocasionar estresse nas espécies vegetais, promovendo um aumento nos compostos antioxidantes, aspecto esse que pode ser relacionado ao aumento dos níveis de pH no solo da área de mineração, assim como a ausência ou deficiência de elementos que são essenciais para a nutrição vegetal.
Environmental conditions can influence the composition and production of secondary metabolites, causing greater or lesser antioxidant capacity in plants. In mining areas there are changes in the environment, which may interfere with the constituents of the plant. In this work, the antioxidant activity of the Eugenia uniflora L. ethanolic extract present in a mining area with a control area was compared, as well as investigations of the condition of the environment. The antioxidant activity was analyzed by two methods: phosphomolybdenum complexation and the free radical sequestration method DPPH ° (2,2-diphenyl1-picryl-hydrazyl). In order to verify the quality of the soils where the plants were, the pH was verified and the presence of some chemical elements was investigated. In the mining region there was no detection of some elements that are essential for plant nutrition: copper, molybdenum, nickel and zinc, as well as a lower concentration of cobalt, which is also considered an essential element. The determination of the pH of the soils allowed to define the soil of the mining area as basic (8.85 ± 0.78), while that of the control area was characterized as acid (5.37 ± 0.35). The high pH value in the mining area is a factor that causes more impacts on plant nutrition than the soil acidity of the control area, because the availability of nutrients is affected to a greater extent. The water analysis indicated that the water quality in the control area is adequate, while in the mining area the hardness, conductivity, calcium and magnesium levels were high because it was a sedimentation basin of liquid effluents from the lime factory . The antioxidant activity of the plant located in the mining area was higher than that of the control area, which is not under the influence of mining activities. In the phosphomolybdenum complex method, the statistical analysis showed that between the extracts of Eugenia uniflora L. of the two analyzed areas there is no significant difference. In the free radical sequestration method (DPPH) there was a significant difference between the different extracts. The highest percentage of antioxidant activity observed was 96.55% for the extract from the mining area, while for the control area it was 92.78%. Some factors can cause stress in the plant species, promoting an increase in the antioxidant compounds, which aspect may be related to the increase of pH levels in the soil of the mining area, as well as the absence or deficiency of elements that are essential for plant nutrition .
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Asplet, William. "Etude des interactions entre les défauts lacunaires et les solutés Y,O, Ti pour mieux comprendre leur rôle dans la formation des nanoparticules d'oxydes dans les aciers ODS." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2056/document.
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Cette thèse est dédiée à l’étude des interactions entre les défauts lacunaires et les solutés (Y, Ti, O) pour mieux comprendre la formation des nanoparticules d’oxyde dans les aciers ODS (Oxide Dispersion Strengthened). Ces aciers sont envisagés comme matériau de structure dans la prochaine génération de réacteurs nucléaires fission et fusion. Leurs bonnes propriétés reposent essentiellement sur une répartition homogène de nanoparticules (YxTiyOz) de très faible taille. Cependant, l’obtention de cette répartition n’est pas encore maitrisée et le mécanisme de formation de ces nanoparticules n’est pas encore bien défini. Des modèles théoriques montrent que la présence de lacunes pendant l’étape de broyage pourrait impacter la formation de ces nanoparticules. Cette étude fait suite à la thèse de C. He et apporte de nouveaux résultats et de nouvelles interprétations et conclusions. Des implantations avec des ions Y, Ti, O ont été réalisées afin de simuler l’étape de broyage de ces aciers ODS. Elles ont permis d’introduire des défauts et les solutés désirés dans la matrice de fer α. Nous avons ensuite étudié les interactions entre les solutés et les défauts générés dans la matrice. La nature des défauts induits a été étudiée en fonction de l’ion implanté et de traitements thermiques après implantation par spectroscopie d’annihilation de positons (PAS) et corrélée avec les profils en profondeur des solutés obtenus par spectrométrie de masse des ions secondaires (SIMS). Les caractéristiques d’annihilation de certains défauts encore inconnues ont pu être déterminées. Les mesures SIMS ont montré que le titane ne migre pas entre 100 et 450°C et que l’oxygène présente un comportement complexe de migration et de piégeage dépendant de la température et de la microstructure des matériaux. Les résultats PAS montrent que les implantations ioniques conduisent à la formation de clusters lacunaires, de complexes lacunes-solutés et de dislocations dont la proportion change en fonction de la profondeur et de la nature de l’ion implanté. Les clusters de lacunes Vn et les dislocations sont détectés au-delà du pic d’implantation avec une fraction plus importante pour les dislocations indiquant que les défauts ont pu migrer pendant l’implantation. La proportion des complexes lacunes-solutés est maximale dans la zone d’arrêt des ions. Elle est en accord avec les énergies de liaison théoriques des complexes lacunes-soluté. La nature et la distribution des défauts formés évoluent en fonction de la température de recuit. Les clusters lacunaires Vn disparaissent entre RT et 300°C alors que les dislocations sont éliminées à partir de 400°C. Des phases oxydes sont détectées pour des recuits à 500 et 550°C en lien avec la contamination en oxygène. Des défauts dont la nature est non identifiée ont été mis en évidence pour des recuits réalisés entre 300 et 400°C dans les implantations O, Y et Y+OThis PhD thesis is dedicated to the study of interaction between vacancies and Y, Ti,O solutes for a better understanding of formation of oxide nanoparticles in ODS steel (Oxide Dispersion Strengthened). These ODS steels are considered as structural material for the next generation of fission and fusion nuclear reactors. Their good properties are induced by the fine dispersion of low size oxide nanoparticles. However, obtaining this distribution is not mastered and atomic scale clustering is not yet defined. Furthermore, it was shown by theoretical models that the presence of vacancy during mechanical alloying could affect the formation of these nanoparticles. This study follows upon on a previous study made by C.He, and bring new results, new interpretation and conclusions. Some implantations with Y, Ti, O ions with several energy have been made in order to simulate the mechanical alloying step used for ODS steel fabrication. Theses irradiations have induced defects and solutes into the iron matrix. Then we characterized samples using positron annihilation spectroscopy (PAS) and secondary ion mass spectrometry (SIMS). The nature of defects was studied according to nature of the implanted ion and the annealing temperature by PAS and correlated to depth profiles of solutes obtained by SIMS. Annihilation characteristics of some defects still unknown were able to be determined thanks to positron lifetime measurements. SIMS analysis showed that titanium doesn’t migrate for annealing experiments between 100°C and 450°C and that oxygen show a complex behavior of migration and trapping dependent on the microstructure of the material. PAS results show that ionic implantations produce vacancy clusters, dislocations and solutes-vacancies complex. Their proportion changes as a function of depth and nature of these irradiations. Vacancy clusters and dislocations are detected deeper than the implantation peak with a higher fraction for the dislocations indicating that the defects were able to migrate during implantations. The fraction of vacancy-solutes complexes is the highest in the ion stopping zone and is in a good agreement with the theoretical binding energy of vacancies-solutes complex. The nature and the distribution of the defects evolve according to the annealing temperature. Vacancy clusters disappear between RT and 300°C while the dislocations are eliminated from 400°C. Oxide phases are detected for annealing at 500 and 550°C in relation with the oxygen contamination during these annealings. Some defects which the nature is not yet identified were highlighted for annealing between 300 and 400°C for Y, O and Y+O irradiations
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He, Chenwei. "Experimental study of the interaction of vacancy defects with Y, O and Ti solutes to better understand their roles in the nanoparticles formation in ODS steels." Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2057/document.
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Les conditions sévères de fonctionnement des réacteurs du futur, Génération-IV, -haute température et fortes irradiations-nécessitent le développement de matériaux adaptés. Les aciers ODS (Oxide Dispersion Strengthened) sont des candidats très compétitifs pour le gainage du combustible en raison de leurs excellentes propriétés de gonflement et de fluage. Ces atouts majeurs sont induits par la fine dispersion de nanoparticules d’oxydes (Y, O, Ti) obtenue par co-broyage de poudres de la matrice et d’oxyde dont les conditions sont à optimiser pour maitriser la distribution en taille et composition de ces nanoparticules. Dans l’objectif de mieux comprendre le mécanisme de formation de ces nanoparticules à l’échelle atomique, la présente thèse met à profit l’utilisation de la spectroscopie d’annihilation de positons (PAS) et de la spectrométrie de masse d’ions secondaires pour étudier l’interaction des défauts lacunaires avec des solutés Y, O et Ti et évaluer leur rôle dans la formation des nanoparticules. Les irradiations avec des ions He ont été effectuées pour révéler les propriétés des défauts lacunaires et les implantations d’Y, Ti, O ont été réalisées pour étudier les interactions de ces éléments Y, Ti, O avec les lacunes dans la matrice de fer. La distribution des défauts en profondeur indique la présence de défauts lacunaires avec une taille plus petite dans la région où la concentration d’Y, Ti, O est la plus élevée. Cet effet est plus prononcé pour O, Y et Ti respectivement. Il est expliqué par la formation de V-X (X=O, Y, Ti) complexes qui réduisent la probabilité de la mobilité et d’agglomération des défauts lacunaires. Les recuits des échantillons implantés Y et O révèlent que des complexes O-lacune sont mobiles à température ambiante, et que l’yttrium ne diffuse pas jusqu’à 550°C alors que des complexes Y-lacunes sont encore détectés comme cela est attendu par des résultats théoriques. Un modèle des premières étapes de la nucléation des nanoparticules est proposé en utilisant les résultats obtenus dans cette thèseThe severe operating conditions of the future nuclear reactor, Generation-IV, -high temperature and high irradiation damage-, require the adapted materials development. Oxide-dispersion strengthened (ODS) alloy is one of the most potential candidates expected to be used for fuel cladding material because of their outstanding swelling and creep properties. Their excellent properties are induced by the fine dispersion of oxide nanoparticles (Y, O, Ti), obtained by mechanical alloying of steel and oxide powders and which has to be better mastered. But the atomic scale clustering mechanism of these nanoparticles is not yet cleared. In this context, the present thesis using positron annihilation spectroscopy (PAS) and secondary ion mass spectrometry (SIMS) sheds light on the interaction of vacancy defects with Y, O and Ti solutes to better understand their roles in the nanoparticles formation. The He irradiations have been performed to reveal the vacancy defects properties and Y, Ti, O implantations realized to study the Y, Ti, O-vacancy interactions in bcc Fe matrix. In all cases, the defects depth distribution shows a lower size of vacancy defects in the region where the concentration of the incident ions Y, Ti and O is the highest. This effect of the ions on the damage formation is more pronounced for respectively O, Y and Ti. It is explained by the formation of V-X (X=O, Y, Ti) complexes which reduce the mobility and agglomeration probability of the vacancy defects. The annealing of the Y and O implanted samples reveals that some O-vacancy complexes are mobile at room temperature and Y doesn’t diffuse up to 550°C whilst Y-vacancy complexes remain as it is expected from theory. A model of the first steps of the ODS nanoparticles nucleation is proposed by using the results obtained in this thesis
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Koefender, Jana. "Crescimento de calêndula e produção de flavonóides em diferentes épocas de semeadura e suprimento hídrico." Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/3160.
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The cultivation of medicinal plants, like marigold, is increasing in Brazil and is an alternative for cultivation in small areas. For this reason it is important to know about its bioclimatic requirements and its phenometric characteristics in order to obtain maximum quality and yield. Thus, the main goals of this work were: evaluate the effect of temperature on Calendula officinalis L. seed germination, testing 15°C, 20°C, 25°C 30°C and 35°C, in the presence and absence of light; determine the phyllochron in three sowing dates (04/06/2005, 06/23/2005 and 10/03/2005); evaluate the effect of the different sowing dates and hydric supply (100%, 85%, 70% and 55% of field capacity) on flower flavonoids and; determine the fresh and dry matter production of the different organs in different sowing dates and when submitted to a 21-day hydric deficient period from flowering on. It was observed that the highest seed germination percentage occurs at the temperature of 20°C, and that temperatures higher than 30°C are harmful to seedlings; sowing dates interfere on the phyllochron and on the number of leaves on both the main and on the first lateral stem; the relation between the thermic sum and plant biomass production is highly significant, the growth of plants being higher in the April and June sowing dates as compared to those of October; water supply in the substratum and the accumulated thermic sum interfere on the growth parameters, the plants submitted to lower water availability in the substratum (55% and 70%), even after rehydration, do not recover fresh and dry matter production along the growing cycle; the best sowing dates for seed production are those of April and June, and for the production of fresh and dry matter of flowers the April date; there is no significant effect of hydric deficiency on flower and seed production parameters; high temperatures cause deleterious effects on growth of plants; Quercetin and Rutin contents on flowers vary along the plant development and with sowing dates, being higher in warmer dates; there is effect of hydric deficiency on plants and; submitted to a hydric supply in the substratum of 55% and 70% of the field capacity at flowering initiation and for a three-week period were favored in the concentration production of Rutin and Quercetin in the flowers.O cultivo de plantas medicinais, como a calêndula, é crescente no Brasil e uma alternativa para produção em pequenas áreas. Para isso é importante conhecer suas exigências bioclimáticas e suas características fenométricas para se obter o máximo de rendimento e com qualidade. Assim, os objetivos, neste trabalho, foram: avaliar o efeito da temperatura na germinação das sementes de Calendula officinalis L., testando 15°C; 20°C; 25°C; 30°C e 35°C, na presença e na ausência de luz; determinar o filocrono em três épocas de semeadura (06/04/2005; 23/06/2005 e 03/10/2005); avaliar o efeito das diferentes épocas de semeadura e de suprimento hídrico (100%, 85%, 70% e 55% da capacidade de campo) nos flavonóides das flores e; determinar a produção de massa seca e fresca dos diferentes órgãos em diferentes épocas de semeadura e quando submetida a um período de 21 dias de deficiência hídrica a partir do florescimento. Foi constatado que a maior percentagem de germinação das sementes ocorre à temperatura de 20°C, e temperaturas superiores a 30°C são prejudiciais às plântulas; as épocas de semeadura interferem no filocrono e no número de folhas da haste principal e da primeira haste lateral; a relação entre a soma térmica e a produção de biomassa de plantas é altamente significativa, sendo o crescimento das plantas maior nas épocas de abril e junho do que naquelas da época de outubro; o suprimento de água no substrato e a soma térmica acumulada interferem nos parâmetros de crescimento, sendo que as menores disponibilidades de água no substrato, de 55% e 70%, mesmo após a reidratação não recuperam a produção de massa fresca e seca ao longo do ciclo; as melhores épocas de semeadura para a produção de sementes são as dos meses de abril e junho e para a produção de massa fresca e seca de flores, a do mês de abril; não ocorre efeito significativo da deficiência hídrica nos parâmetros de produção de flores e de sementes; temperaturas elevadas causam um efeito deletério no crescimento das plantas; os teores de Quercetina e Rutina nas flores variam ao longo do desenvolvimento das plantas e nas épocas de cultivo, sendo mais elevados nas épocas mais quentes; há efeito da deficiência hídrica na planta e; as plantas submetidas a um suprimento hídrico no substrato, de 55% e 70% da capacidade de campo, no início do florescimento e por um período de três semanas, foram favorecidas na produção de concentração de Rutina e de Quercetina nas flores.
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Prill, Nadine. "Effects of environmental change on plant performance and plant-herbivore interactions." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:c58761e9-666c-4b7d-a78a-d70de7f253d4.
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Global environmental change fundamentally affects plants and their interactions with other species, and this has profound impacts on communities and ultimately ecosystems. In order to understand the mechanisms involved, we need to elaborate on the combined effects of different global change drivers on multiple levels of plant organization, including the biochemical level (production of defence compounds), the whole organism, the population, and the plant-herbivore interaction level. This thesis investigates (1) the combined effects of factors related to climate change and habitat fragmentation on Brassica nigra and (2) the effects of Zn soil pollution on the heavy metal hyperaccumulator Noccaea caerulescens at these different levels. Common garden and greenhouse experiments with B. nigra applied drought stress and elevated CO2 to examine climate change impacts, while crossing treatments (inbreeding and between-population outbreeding) were used to investigate habitat fragmentation effects. Heterosis was lost under drought stress, and there were several interactive effects of the experimental treatments that varied within and among populations. In a greenhouse experiment with N. caerulescens, plants were grown on soil with different amounts of zinc. Plants had greater herbivore resistance when grown on Zn-amended soil, and invested more in herbivore tolerance when grown on soil without added Zn. In general, the results indicate that factors related to global environmental change have complex and interactive effects on different levels of plant organization. The findings are discussed in terms of their implications for ecology, evolution and conservation.
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Santos, Vitor Francisco dos. "Estudo das alterações da parede celular durante ativação de mecanismos de defesa em Momordica charantia como fator de produção de metabólitos secundários bioativos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-26112014-162605/.
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Momordica charantia é uma espécie de planta pertencente à família Cucurbitaceae. No Brasil, é conhecida pelo nome popular de Melão de São Caetano. É encontrada em grande parte do globo terrestre, sendo que no Brasil é observada nas regiões litorâneas e principalmente nas regiões do interior do país. Escolhemos o estudo com Momordica charantia devido suas propriedades terapêuticas conhecidas serem de grande interesse. Ela vem ganhando cada vez mais reconhecimento através de pesquisas científicas realizadas, visto que, já é utilizada a milhares de anos através da cultura popular. Tais pesquisas têm confirmado e entendido cada vez mais as propriedades medicamentosas desta planta e os mecanismos responsáveis por tais funções nesta espécie, sendo as propriedades antidiabéticas, antivirais e anticancerígenas as de maior destaque. Os experimentos realizados em torno da Momordica charantia, na busca destes compostos foram todos realizados utilizando extratos retirados dos próprios tecidos já diferenciados na planta adulta (sementes, folhas, raízes e frutos). Neste trabalho, foi realizado a pesquisa de metabólitos secundários produzidos pela cultura de células em suspensão de Momordica charantia durante a fase de crescimento desta e após a realização de ensaios de elicitação com Ácido Salicílico (AS). Nosso laboratório vem se dedicando aos estudos da composição da parede celular vegetal e suas alterações, bem como dos mecanismos de defesa empregados pelas células em suspensão em condições de estresse biótico e abiótico. O ácido salicílico é um dos hormônios vegetais envolvido em vários mecanismos de respostas que envolve o estresse vegetal e de desenvolvimento da planta tais como o de garantir resistência a patógenos por exemplo. Quando ocorre algum processo de infecção ou lesivo para a planta, ocorre um aumento na concentração de AS no interior da planta. Esse aumento leva a ativação de certas vias metabólicas que culminam na produção de metabólitos secundários e na degradação, fragmentação ou espessamento da parede celular. Como reposta dos ensaios de elicitação realizados podemos comprovar os efeitos do AS mediados na produção de metabólitos secundários que foram aumentados conforme a concentração de AS. Foi utilizado para os ensaios de elicitação AS nas concentrações de 0,5 , 1,0 e 5 mmol/L. Para o monitoramento da cultura e averiguação da efetividade dos ensaios de elicitação foi utilizado a monitoria através da dosagem de proteínas totais, compostos fenólicos totais e açúcares redutores totais tanto liberados para o meio extracelular quanto produzidos no meio intracelular. Foi determinado as variações dos componentes da parede celular durante a fase de crescimento e após os ensaios de elicitação onde foi comprovado que quanto maior a concentração de AS, maiores são os fragmentos de açúcares fragmentados da parede celular. Foi evidenciado também a presença de triterpenos na cultura celular (em comparação com os padrões isolados da planta), tanto na fase de crescimento e também após a indução com os ensaios de elicitação com AS.Momordica charantia is a plant from the Cucurbitaceae family. In Brazil, it is known by the popular name of Melão de São Caetano. It is found across the whole world, and in Brazil it can be found in coastal and interior regions of the country. The aim to study Momordica charantia is due to its known therapeutic properties that are already used for thousands of years through popular culture. The studies have confirmed and understood various drug-like properties of this plant and the mechanisms responsible for such functions in this species, such as antidiabetic, antiviral and anticancer properties. The researches with Momordica charantia were all performed using extracts obtained from seeds, leaves, roots and fruit. In this work, the isolation and characterization of metabolites as standards from leaves and stems of Momordica charantia was performed. The research of secondary metabolites produced in cell culture suspension of Momordica charantia without elicitor or after elicitation with salicylic acid (SA) was conducted. Salicylic acid is a plant hormone involved in various mechanisms of responses. When the plant suffers an infection or injury, it is followed by an increase in AS concentration. This increase leads to activation of certain metabolic pathways that culminate in the production of secondary metabolites and degradation, fragmentation or cell wall thickening. AS was utilized for the elicitation experiments at 0.5, 1.0 and 5 mmol/L. For the monitoring of plant cell culture, it was determinate the total protein, phenolic compounds and reducing sugars content, into the extra and intra cellular medium. Where it was verified that AS modulates the production of these molecules in culture. After this, we determined the variation in the oligosaccharides in the extracellular medium obtained in the presence or absence of AS. It was observed the degree of polymerization of oligosaccharides higher when increase AS concentration in the medium. In conclusion, this study can demonstrate the effects of SA on the production of secondary metabolites in plant cell culture, which were increased as the concentration of AS increased. The presence of triterpenes in cell culture was confirmed to compare the molecules obtained from culture with that isolated from plant standards.
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Alm, Bergvall Ulrika. "Food choice in fallow deer : experimental studies of selectivity /." Doctoral thesis, Stockholm : Department of Zoology, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6789.
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Ornelas, Gabriela R. "The District's Stepchild: The Total Erasure of Low-Income Latinx Students' Needs at Continuation High Schools." Scholarship @ Claremont, 2017. http://scholarship.claremont.edu/pitzer_theses/83.
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My study explores the underlying factors that allow systemic structural issues to exist within continuation high schools which result in the low educational performance of low-income Latinx continuation students. My study focuses on educators’ experiences, as I conducted 20 in-depth, semi-structured interviews with Southern California continuation high school teachers. I focused on the following areas of study: the teacher’s career, the teacher’s interactions with students, and the teacher’s opinions regarding their accessibility to funding and resources. My findings indicate that teachers, the outer community, and school-board administrators utilize cultural deficit thinking and stigmatization as tools of total erasure to exchange low-income Latinx students’ social identities with racist and classist stereotypes; in consequence, these mechanisms allow the district to impose invisibility on students’ academic and emotional needs in order to justify the formation and maintenance of institutional challenges for administrators’ fiscal benefit. Overall, these results reaffirm that our educational system reproduces social inequality; the total erasure of low-income Latinx continuation students’ academic and emotional needs permits the persistence of systemic structural issues informed by racist and classist stereotypes. My research calls for avenues of communication between administrators, teachers, and the outer community to address institutional barriers and, subsequently, establish equitable funding distributions to promote continuation high school students’ educational success with an understanding of the increased academic, emotional, and social needs of low-income Latinx students.
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Fefer, Sarah A. "The Positive Illusory Bias: Do ADHD Symptoms Differ Among Young Adolescents with Accurate Versus Discrepant Self-Perceptions?" Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3098.
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The purpose of this study was to gain insight into whether inattentive, hyperactive/ impulsive, and depressive symptoms differ among young adolescents with negative, accurate, or positive self-perceptions of their academic and social competence. Current literature suggests that elementary-age children with ADHD display overly positive self-perceptions, often referred to as the positive illusory bias (PIB; Owens, Goldfine, Evangelista, Hoza, & Kaiser, 2007). Self-reports of academic and social self-concept were compared to teacher ratings and test scores for 164 middle school students in an effort to determine if the PIB was present within this sample. Inattentive and hyperactive/impulsive symptoms were found to be significantly higher among the positive self-perception group in the academic domain with teacher ratings as the indicator of competence, while depressive symptoms were found to be significantly higher among the negative self-perception group. In the social domain, only inattentive symptoms were shown to be significantly higher in the positive self-perception group compared to the negative and accurate groups. Interestingly, there were no significant differences between groups with achievement test scores as the indicator of academic competence. These findings provide information about the PIB in young adolescents, an understudied group. Implications related to research and practice are also presented.
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Kultima, Kim. "Transcriptomics and Proteomics Applied to Developmental Toxicology." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7921.
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Olsson, Anna. "Dansundervisning för elever med autism och ADHD : En kvalitativ studie av gymnasielärares erfarenheter ur ett sociokulturellt perspektiv." Thesis, Stockholms konstnärliga högskola, Institutionen för danspedagogik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uniarts:diva-748.
Full textAbstract:
The aim of the study is to contribute knowledge and increase the understanding of teaching dance to students aged 16-18 with autism and ADHD in upper secondary school in Sweden by investigating teachers understanding of adaptation and the reason for students experiencing difficulties related to their diagnosis. The study also investigates the different strategies used by the teachers to adapt their teaching. The study uses a qualitative method and empirical data was collected through semi-structured interviews with four dance teachers. The data was analysed within the framework of a sociocultural perspective using concepts such as mediation, affordance and intellectual tools defined as given models for thinking. The results of the study show firstly that teachers’ understanding of different ways to adapt teaching and ways of understanding the reason for students experiencing difficulties, affects how they adapt and design their teaching. Secondly the study shows that the strategies used by the teachers mainly strives for making the teaching clear and predictable, to improve students’ self-esteem and to build good relationships to the students, and among the students. The study concludes that more knowledge about the subject is needed to further support the teachers in their work.
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Schmillen, Justin Alan. "INFLUENCES OF ENVIRONMENTAL EDUCATION PROGRAMS ON THE PARTICIPANT’S AFFINITY FOR NATURE." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/307.
Full textAbstract:
This study was conducted to determine the change, and the factors influencing the change, in the participant’s affinity for nature resulting from an environmental education experience. In addition, this study also examined the change and factors of change in aspects of the participant’s affinity for nature that directly relate to marine and coastal resources and environments. An adapted version of the Affinity for Nature scale, an outcome measuring instrument used by the American Camp Association was used to collect data from participants (n=529) at Rancho El Chorro Outdoor School and Camp Ocean Pines, whose experience included an overnight component and a marine science component in the curriculum. Comparisons of overall mean scores were used to determine if affinity for nature changed due to participation in the environment education program. Analysis of variance was used to determine which participant characteristic and experiential variables had a significant influence on affinity for nature index scores. Findings indicated that participation in environmental education experience had a positive change on affinity for nature scores. Residence, ethnicity/language, and gender were also found to significantly influence sense of community various affinity for nature index scores.
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Beard, Karen Stansberry. "An Exploratory Study of Academic Optimism and Flow of Elementary School Teachers." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1217020480.
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Palena, Emily I., and Caroline T. Spurgin. "Landscapes to Learnscapes: Exploring Schoolyard-based Education." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/pitzer_theses/34.
Full textAbstract:
This thesis explores schoolyard-based education as a viable and necessary method for rectifying the shortcomings within the American public school system and the Nature-deficit Disorder epidemic. We argue that schoolyard-based education should be fully integrated into the school system, not in the sole form of popularized school gardens, but as a standard teaching method. We show this using extensive research and a case study of three elementary schools in Claremont, California.
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Lee, Jeng-Han, and 李正漢. "Study of Dopant Profiling and Defect Isolation Using Secondary Electron Potential Contrast." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/53330313102143526125.
Full textAbstract:
博士國立交通大學
光電工程學系
100
This study investigates the defect isolation and dopant profiling using secondary electron potential contrast (SEPC). A novel primary electron energy adjustment method is proposed to remedy the imperfections in traditional SEPC method, which uses fixed primary electron energy. For dopant profiling, a novel in situ nano-probe biasing is applied to enhance the SEPC signal, restoring the missing dopant contrast successfully. First author discusses the application of SEPC is applied to investigate the leakage and high resistance in a metal oxide semiconductor field effect transistor (MOSFET). The contact nodes in an MOSFET can be classified into four categories: the polysilicon gate node, p+/n-well node, n+/p-well node, and, well nodes. Most studies set primary electron beam energy (EPE) at 1 keV and used potential contrast to identify the gate oxide rupture and continuity failures. However, the bright and dark contrast of samples cannot distinguish these four nodes types well. For instance, the contrast of a p+/n-well node and well nodes is bright in scanning electron microscope (SEM). However, a leaky p+/n-well node exhibits the same brightness as the well nodes, an insufficiency of the EPE 1 keV condition for identifying p+/n-well nodes and well nodes. Previous studies indicate that the contrast of SEPC arises from the surface charging effect, which is initiated by the interactions between the primary electron beam and sample. The EPE 1 keV condition results in the positive charging on the sample. Positive charging will set the p+/n-well node in forward bias and leak positive charges into well nodes. Thus, the EPE 1 keV condition cannot be used to distinguish the p+/n-well node and well nodes. This can be solved by setting the p+/n-well node in reverse bias. This study increases the EPE to 5 keV to reverse surface charging from positive to negative. Experimental results demonstrate that the 1 keV and 5 keV EPE conditions can be used to identify these four nodes. Finally, the analytical method was applied to a real failure case and no abnormality under the conventional EPE=1 keV condition was observed. However, the proposed EPE=5 keV can isolate a defect successfully and complete the imperfect conventional method. The second part of this study discusses the application of SEPC to diode dopant profiling. Since 1967, researchers have observed dopant contrast in SEM image. The dopant contrast arises from built-in potential across the diode. This study also uses this property to identify a p+/n-well junction leakage path in a static random access memory (SRAM). However, for a small bandgap material like silicon, the built-in voltage is as small as 1.12 eV. Dopant contrast is weak and, in the worse case, no contrast is observable. The surface-damaged layer generated by sample preparation is believed to be the cause of dopant contrast reduction, inhibiting the application of SEPC to the integrated circuit (IC) failure analysis. For SEPC enhancement, this study studied the contrast effect under different sample preparation methods. By triggering the diode in the reverse bias condition through in situ nano-probe biasing, that dopant contrast can be restored. The SEPC image was digitalized and quantified for conversion of image contrast to the voltage scale, allowing the identification of the depletion region and electrical junction. The overlap length between the poly silicon gate and p+ region is also depicted by the two-dimensional (2D) imaging. The proposed method can maintain stable voltage conditions in the junction, facilitating the inspection of dopant area by SEM, and the development of an efficient method for examining dopant areas. Experimental results also confirmed the method has promising application in site-specific junction inspection. Finally, the novel method was applied to identified the failure cause of a current mirror mismatch. The inspection method successfully identified a 0.4 µm p-well layer misalignment caused by the mismatch. The experimental split also confirmed that a p-well misalignment exceeding 0.4 µm will cause failure.
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Vinciguerra, Salvatore. "Lived experiences of secondary instrumental music teachers who teach students with learning disabilities." Thesis, 2016. https://hdl.handle.net/2144/16836.
Full textAbstract:
Very little research is published on teaching music to students with learning disabilities. Nevertheless, federal law mandates that instruction of such students take place in all public schools. The purpose of this study was to investigate the lived experiences of four secondary instrumental music teachers who teach five students with learning disabilities. This study looked at the interactions between teachers and these students and examined how their experiences informed teaching practices. Phenomenological in design, this study included data collected from journals, as well as interviews, relevant artifacts, and direct observations of the teachers. My goal was to provide data for music teacher training programs and for these teachers to help each class of their students educate students with learning disabilities.
Results showed that the teachers were aware of the needs of students with learning disabilities. Teachers became frustrated with occurrences of undisclosed diagnoses of such students and those with Attention-Deficit/Hyperactivity Disorder, and that they had received little guidance from Individualized Education Programs or other documents designed to inform teachers about accommodations for those with disabilities. Successful accommodations depended on the experience or training of the teachers and the severity of the disability, as well as how much the students had previously learned to cope with their learning disabilities. Students were rarely aware of specific interventions or adaptations teachers had made to accommodate a disability. Instructors employed general teaching techniques that aligned with Universal Design for Learning (UDL). Pedagogical information given in this study would benefit music education and add more data to the sparse amount of work being done on teaching instrumental music to students with learning disabilities.
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Sinopoli, Katia Joanne. "Inhibitory Control and Reward Processes in Children and Adolescents with Traumatic Brain Injury and Secondary Attention-deficit/Hyperactivity Disorder." Thesis, 2010. http://hdl.handle.net/1807/26326.
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Children with traumatic brain injury (TBI) often experience difficulties with inhibitory control (IC), manifest in both neurocognitive function (poor performance on the stop signal task, SST) and behavior (emergence of de novo attention-deficit/hyperactivity disorder, or secondary ADHD, S-ADHD). IC allows for the regulation of thought and action, and interacts with reward to modify behaviour adaptively as environments change. Children with developmental or primary ADHD (P-ADHD) exhibit poor IC and abnormalities when responding to rewards, yet the extent to which S-ADHD is similar to and different from P-ADHD in terms of these behaviours is not well-characterized. The cancellation and restraint versions of the SST were used to examine the effects of rewards on 2 distinct forms of IC in children and adolescents divided into 4 groups (control, TBI, S-ADHD, and P-ADHD). The SST requires participants to respond to a “go signal” and inhibit their responses when encountering a “stop signal”. Rewards improved performance similarly across groups, ages, and cancellation and restraint IC tasks. Adolescents exhibited better IC and faster and less variable response execution relative to children. Significant IC deficits were found in both tasks in the P-ADHD group, with participants with S-ADHD exhibiting intermediate cancellation performance relative to the other groups. Participants with TBI without S-ADHD were not impaired on either task. The relationship between neurocognitive and behavioral IC was examined by comparing multi-informant ratings of IC across groups, and examining the relationship between ratings and IC performance on the SST. Participants in the control and TBI groups were rated within the typical range, and exhibited fewer problems than either of the ADHD groups, who differed from each other (the P-ADHD group was rated as more inattentive than the S-ADHD group). Moderate to high concordance was found between parent and teacher reports, each of which was poorly concordant with self-reports. The P-ADHD and S-ADHD groups were unaware of their own deficits. Poorer IC predicted parent and teacher classification of participants into ADHD subtypes, although IC did not predict rating concordance. Despite similar clinical presentations, S-ADHD and P-ADHD differ in the phenotypic expression of behaviour and manifestation of IC across contexts.
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Tugizimana, Fidele. "Metabolite profiling of defence-related secondary metabolites in tobacco cells, in response to ergosterol, a steroid from fungal membranes." Thesis, 2012. http://hdl.handle.net/10210/8088.
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M.Sc.Plants have the ability to continuously respond to various stimuli which alter their physiology, morphology and development. These stimuli may be abiotic or biotic and range from essential to toxic in their effects. One of these stimuli is a steroid from fungal membranes, ergosterol (C28H44O), which does not occur in plants. Ergosterol acts as a pathogen-associated molecular pattern molecule and triggers defence mechanisms in plants, characterised by highly regulated and interrelated events that include the elicitation of the oxidative burst and expression of a number of defencerelated genes. However, the ergosterol-induced global cellular reprogramming of the host has not been fully investigated in all aspects. No metabolomic study has previously been conducted to elucidate, for instance, the effect of ergosterol on plant metabolism. A clear and broader understanding of the molecular mechanisms involved in plant : ergosterol interactions is of paramount importance, for it would open up possibilities of developing novel, more effective and sustainable strategies to control or eradicate fungal diseases in plants. In plants, the metabolome is a compilation of all primary and secondary metabolites. The latter are the final recipients of genetic information, and their levels can influence gene expression and protein stability. Metabolite patterns reveal the actual cellular dynamic environment. Hence, qualitative and quantitative measurements of extra- and intracellular metabolites yield insights into the cellular processes that control the biochemical phenotype of the cell, tissue or whole organism. Metabolomics, the most recent of the ‘omics’ approaches, is the holistic analysis of metabolites present within a biological system under specific physiological conditions. In the present study a metabolomic approach was used to elucidate and analyse changes in the metabolism of tobacco (Nicotiana tabacum) cells following ergosterol treatment. Special attention is given to sesquiterpenoids since the antimicrobial compounds (phytoalexins) isolated from plants within the Solanaceae are mostly bicyclic sesquiterpenoids. Suspension of tobacco cells were treated with different concentrations (0 - 1000 nM) of ergosterol and incubated for different time periods (0 - 24 h). A viability assay, based on the ability of viable cells to reduce 2,3,5- triphenyltetrazolium chloride (TTC), was used to determine whether cell death occurred due to ergosterol treatment. No loss of cell viability was observed over the concentration range and time periods used in this study, indicating that the observed responses were due to the treatment alone and possible secondary responses due to cell death could be excluded. Intracellular metabolites were extracted with two methods: a selective dispersive liquid-liquid micro extraction and a general methanol extraction. Chromatographic techniques (TLC/HPTLC, GC-FID, GC-MS, GC×GC-TOF-MS, UPLC-MS) and 1H NMR spectroscopy were used for quantitative and qualitative analyses. Multivariate data analyses (PCA and OPLS-DA models) were used to extract interpretable information from the multidimensional data generated from the aforementioned techniques.
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Korcsmáros, Gabriel. "Vlastnosti bodových defektů v CdTe při teplotách 300 - 600 K." Doctoral thesis, 2019. http://www.nusl.cz/ntk/nusl-404554.
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The thermal stability of p-type CdTe crystals by using conductivity and Hall-effect measurements have been studied at room and slightly increased temperatures. It was observed that thermal changes often implicate an anomalous behavior of the hole density characterized by reversible decrease/increase in a heating/cooling regime. This anomaly was explained by a transfer of fast diffusing donors between Te inclusions and the bulk of the sample. Sodium and potassium were determined by the Secondary Ion Mass Spectroscopy (SIMS) as the most probable diffusing species. To verify this behavior samples were also treated in saturated NaCl solution for different time intervals in order to examine the influence of the oxide layer and sodium on the surface of the sample. To determine the structure of the surface the sample was characterized by ellipsometric and X-ray photoelectron spectroscopy (XPS) and SIMS. Very low determined diffusion coefficient of Na was explained by trapping of Na in Cd sublattice
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Pilkington, Colin Leon. "Constructing programs, how children with Attention Deficit Hyperactivity Disorder (ADHD) learn to program." Diss., 2007. http://hdl.handle.net/10500/1631.
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Many learners find the study of introductory computer programming difficult. This is
also true of children with attention deficit hyperactivity disorder (ADHD), and we need
an improved understanding of how they learn programming. After reviewing the
constructivist approach to teaching and learning and investigating ADHD, this study
explored strategies for constructive learning of introductory programming. The aim
was to evaluate the effectiveness of the Karplus learning cycle to teach introductory
programming. This was done through qualitative research from an interpretive
perspective. Action research techniques were employed and data analysed using
grounded theory methods. Four major constructivist teaching categories emerged,
all of which support the use of the Karplus cycle. It is concluded that the three-phase
Karplus cycle can be used to assist these learners learn introductory programming.
However, it needs to be understood more broadly and the middle phase broken into
two subphases to ensure effective learning.Mathematical Sciences
M. Sc. (Mathematical Sciences)
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Armanjo, Jahanmehr. "The influence of microstructural deformations and defects on mechanical properties in cast aluminium components by using Digital Image Correlation Techniques (DICT)." Thesis, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-28022.
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Digital image correlation techniques (DICT), a non-contact deformation measuring technique based on gray value digital images, have become increasingly used over the last years. By using the DIC technique during a tensile test, the deformation behavior of different engineering material under an applied load can be determined and analyzed. Digital images, acquired from a tensile test, can be correlated by using DICT software and from that the local or global mechanical properties can be calculated. The local or global mechanical properties determination of a flat test specimens are based on the displacements or changes in a previous stochastic sprayed or natural pattern. The used material for this purpose is cast silicon (Si) based aluminium (Al) component, designated as AlSi7Mg0.3 (Anticorodal-78 dv). The hypoeutectic Al- Si alloy is widely applicable for engine constructions, vehicle and aerospace constructions, shipbuilding, electrical engineering and constructions for food industry. There are many microstructural parameters in a binary system Al- Si alloys, which the mechanical properties can be depended on, for instance phase distribution, Secondary Dendrite Arm Spacing (SDAS), morphology of Si particles (Roundness) and microscopic defects or pores. All these parameters can contribute to enhance the proper mechanical performance (e.g. Strength and ductility) in the Al-Si cast components.
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Akter, Pervin. "Plant Root Exudates." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-002B-7D35-3.
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Naidoo, Nathasia. "Impact of educator knowledge of attention decifit hyperactivity disorder on teaching strategies." Diss., 2012. http://hdl.handle.net/10500/11899.
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Attention Deficit Hyperactivity Disorder (ADHD), an intellectual impairment, generally characterised by inattentiveness and impulsivity has become prevalent in South African schools. ADHD learners require support from within the classroom to accommodate their academic and behavioural needs. A quantitative research was undertaken to determine the impact of an educator's knowledge of ADHD on teaching support strategies. An educator's ADHD knowledge is based on their understanding of the diagnosis, causes, symptoms and management of ADHD as well as the effect that ADHD has on a learner's classroom skills. Data was obtained from responses to questionnaires from randomly selected respondents within randomly selected government secondary schools in the Umlazi District of Kwa-Zulu Natal. The data was descriptively analysed to conclude that the level of ADHD knowledge possessed by educators impact on the appropriateness of their teaching strategies. There is a need to impart knowledge regarding learning barriers to educators, to ensure the efficacy of teaching strategies.Inclusive Education
M. Ed. (Inclusive Education)
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Girard, Lapointe Julie. "Effet de la participation au projet TRANSITION sur l’engagement et le rendement scolaires des jeunes ayant un TDAH à la fin de la première année du secondaire." Thèse, 2014. http://hdl.handle.net/1866/11519.
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Hartley, Llewellyn Henry. "Barriers to formal communication in the SANDF." Diss., 1998. http://hdl.handle.net/10500/16911.
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This dissertation is an exploratory study aimed at empirically identifying and examining manifestations of communication barriers in the South African National Defence Force. A convergence model of communication is presented, describing the stages involved when individuals share the same information. The convergence model of communication delineates the relationship among the physical, psychological, and social aspects of communication. Two complementary theorems deduced by Kincaid (1988) from the convergence principle and the basic cybernetic process involved in information processing are applied in the analyses. The
theorems specify the conditions under which intercultural communication will lead to convergence between members of different cultures involved. An empirically testable model was developed to collect information about possible communication barriers. The barriers are an indication of the restrictions on communication in the system and therefore indicate the possibility of restricting cultural convergence.Communication
M.A. (Communication)
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Wang, Lurong. "Immigration, Literacy, and Mobility: A Critical Ethnographic Study of Well-educated Chinese Immigrants’ Trajectories in Canada." Thesis, 2011. http://hdl.handle.net/1807/27608.
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This dissertation interrogates the deficit assumptions about English proficiency of skilled immigrants who were recruited by Canadian governments between the late 1990s and early 2000s. Through the lens of literacy as social practice, the eighteen-month ethnographic qualitative research explores the sequential experiences of settlement and economic integration of seven well-educated Chinese immigrant professionals. The analytical framework is built on sociocultural approaches to literacy and learning, as well as the theories of discourses and language reproduction. Using multiple data sources (observations, conversational interviews, journal and diary entries, photographs, documents, and artifacts collected in everyday lives), I document many different ways that well-educated Chinese immigrants take advantage of their language and literacy skills in English across several social domains of home, school, job market, and workplace.
Examining the trans-contextual patterning of the participants’ language and literacy activities reveals that immigrant professionals use literacy as assistance in seeking, negotiating, and taking hold of resources and opportunities within certain social settings. However, my data show that their language and literacy engagements might not always generate positive consequences for social networks, job opportunities, and upward economic mobility. Close analyses of processes and outcomes of the participants’ engagements across these discursive discourses make it very clear that the monolithic assumptions of the dominant language shape and reinforce structural barriers by constraining their social participation, decision making, and learning practice, and thereby make literacy’s consequences unpredictable. The deficit model of language proficiency serves the grounds for linguistic stereotypes and economic marginalization, which produces profoundly consequential effects on immigrants’ pathways as they strive for having access to resources and opportunities in the new society.
My analyses illuminate the ways that language and literacy create the complex web of discursive spaces wherein institutional agendas and personal desires are intertwined and collide in complex ways that constitute conditions and processes of social and economic mobility of immigrant populations. Based on these analyses, I argue that immigrants’ successful integration into a host country is not about the mastery of the technical skills in the dominant language. Rather, it is largely about the recognition and acceptance of the value of their language use and literacy practice as they attempt to partake in the globalized new economy.