Dissertations / Theses on the topic 'Noel Settings'

Due to their unique characteristics, military domains contain various peculiarities that directly or indirectly and favourably or unfavourably impact the development of software products. Observations of systems development in the Brazilian Navy for many years have shown that systems are developed and delivered usually with many delays, and during development there are many changes to the requirements initially elicited. Since many authors in the software engineering literature agree that problems in requirements account for more than 70% of total system development failures, it seemed to be logical that any effort to solve the problems encountered in the military environment should start focusing on the requirements area. Currently several techniques and approaches already exist that support the execution of activities in this phase. With this abundance of techniques, it becomes a difficult task for the analysts to select the best technique in a given circumstance. To support the selection of these techniques, several frameworks were also created, each one guided by a respective group of influencing factors. This study examined, in a detailed manner, these techniques and frameworks, and noticed that there are still issues to be addressed to guide the selection of elicitation techniques, especially in a complex environment such as the military one. To elicit these issues an exploratory qualitative research was performed. The results showed that social issues rather than technical ones were the main concern in the domain under study. Issues such as hierarchy and high staff turnover interfere in the requirements process but are yet not addressed. The findings of the qualitative research are the first contribution of the thesis. Based on these results this research proposed a novel framework for requirements elicitation within the context of a military environment taking into account social and technical factors, which is the second contribution of the thesis. Such a framework was developed following Conflict Theory from sociology. This framework organized a selection of techniques based on possible solutions to conflicts. Finally, the solution was evaluated to assess its efficacy. This evaluation was based on qualitative and quantitative research. Based on the evaluation results the framework was updated.

O objetivo deste trabalho é, à luz da Literatura Comparada, tecer uma rede de vínculos entre os romances O Amanuense Belmiro, de Cyro dos Anjos, e Para Sempre, de Vergílio Ferreira, para cotejá-los, realçando suas semelhanças e dessemelhanças, e, conseqüentemente, compreendê-los melhor. Para isso, após breves considerações sobre determinados conceitos relativos à composição do romance, como enunciado e enunciação, narrador e narratário, o foco narrativo, o espaço e a personagem, centralizamos a discussão no conceito de tempo distinguindo três noções: tempo físico, tempo interior e tempo lingüístico, com destaque para as duas últimas e o utilizamos como eixo no estudo das obras, na intenção de verificar como os narradores-personagens vêem seu passado e vivem seu presente. No que tange ao tempo lingüístico, privilegiamos o estudo do uso dos verbos, dentre outras palavras temporais, a fim de verificarmos os efeitos de sentido nas escolhas dos dois autores; quanto ao tempo interior, que não é marcado pelo relógio, mas pela intensidade com que as personagens vivem diferentes momentos, enfatizamos o estudo da relação das personagens com o passado. Também, em virtude da clara diferença entre os tipos de romance analisados, destinamos considerável parte do trabalho ao estudo do gênero narrativo.
The aim of this paper is to weave a set of relations, at the light of the Comparative Literature, between the novels O Amanuense Belmiro (Cyro dos Anjos, 19XX) and Para Sempre (Vergílio Ferreira, 19XX), highlighting similarities and differences in a way such as to provide a deeper understanding of them. To cope with this task, after briefly considering some concepts related to the novel composition, like the enunciation and the enunciated, the narrator and the narrated, the point of view, the setting, and the character, we centered the discussion over the concept of time making a tripartite distinction among time notions: the physical, the internal, and the linguistic, with emphasis on the latter two using it as an axis in the study of the novels, seeking to verify how the character-narrators see through their past and live their present. With regard to the linguistic time, we gave particular attention to the study of verbs, detached from other temporal words, in order that we could note the meaning effects resulting from the authors verb choices; as for the internal time, which is not measured by the clock, but by the intensity with which the characters go through different moments, we focused our study on the relation of the characters with the past. Also, owing to the clear difference between the types of novel analyzed, we dedicated a considerable effort to the study of the narrative genre.

Calcium phosphate cements are in-vivo setting, injectable calcium phosphate based biomaterials. They are made of calcium phosphate salts which when mixed with water react to form apatite, the mineral phase of bones and teeth. This study investigates a novel way of forming calcium phosphate cements using bioactive glasses. The aim of the work was to discover a novel route of synthesis using a silicate bioactive glass. Fifteen glass compositions were produced designed to investigate P2O5 content, CaF2 content and calcium to sodium ratio within the glass. Glasses were produced via a melt-quench route before being milled and sieved to below 38 μm. The bioactive glass and Ca(H2PO4)2 powders were mixed in an overall calcium to phosphate ratio of 1.67. The cement powder was then reacted with a 2.5 % solution of Na2HPO4. The paste was then mixed and then placed into cylindrical moulds. Eight samples were immersed into Tris buffer solution for 1 hour, 1 day, 7 days or 28 days. The compressive strength was measured for each specimen as well as SEM performed and the setting times for each composition was studied using the Gilmore needle test. The cement phase was analysed using 31P & 19F MAS-NMR, FTIR and XRD. The results showed that both compressive strength and setting time was dependent upon glass composition. As sodium content was increased both the initial and final setting times decreased. Increased fluoride addition caused a decrease in the setting time. In the fluoride free compositions octacalcium phosphate was identified in all compositions. The cement setting reaction for these compositions followed a similar reaction of first forming dicalcium phosphate dihydrate which transformed to octacalcium phosphate then eventually hydrolysing to hydroxyapatite. When fluoride was incorporated into the cement the phases formed were fluoridated-apatite and DCPD. In conclusion a novel method of producing calcium phosphate cements was discovered using a bioactive glass as a reactive precursor. It was shown that the cement phase, setting time and compressive strength could all be altered by changing the glass composition.

To properly evaluate initiatives targeting children's fruit and vegetable (FV) consumption, we need feasible and valid dietary assessment methods that are time, cost, and resource effective. The objectives of this study were to test the feasibility and validity of two methods, digital imaging (DI) and aggregate plate waste (APW), for assessing children's FV consumption. UVM dietary assessment team graduate students prepared and distributed FV snacks in two pre-school classrooms over 30 consecutive school days. Feasibility of APW was tested by recording the frequency and weight of waste sorting errors by pre-school children and performing paired t-tests comparing uncorrected and corrected FV waste. Feasibility was tested for DI by determining the total number of individual FV snacks from which FV consumption could be estimated using the digital images. Validity was tested for DI using paired t-tests to compare FV consumption as assessed by DI against actual consumption as assessed by weighed plate waste (WPW). A total of 159 cluster APW weights were recorded during the 20 days of APW collection, with an overall mean difference of 0.57 grams (p=0.440) between uncorrected and corrected FV waste. Researchers were able to capture 100-percent usable digital images, effectively displaying 214 individual FV snack servings over the 10-day DI study period. Percent agreement between the two digital image coders was 99.1-percent. DI estimations for individual FV item and cumulative consumption were strongly correlated with WPW (all above r=0.97). Overall FV consumption as estimated by DI differed from WPW by less than one gram, and DI estimations for individual FV items differed from WPW by no more than two grams. Paired t-tests revealed no significant difference between DI estimations of clementine (p=0.954) and peapod (p=0.806) consumption and WPW measurements. However, paired t-tests indicated statistically significant differences between DI and WPW measurements for overall (p=0.001), grape (p=0.031), carrot (p=0.008), and pepper (p=0.027) consumption. Both methods were feasible for assessing mean FV consumption. DI estimations for individual FV items and cumulative consumption were strongly correlated with WPW, suggesting that despite statistical significance between DI and WPW measurements in some cases, the DI method is still precise for mean FV consumption evaluation. APW may be especially advantageous for rapid and efficient evaluation of behavior change in response to interventions targeting children's FV consumption. Due to ease of administration and instantaneous results, the APW method reduces the need for trained research staff to be present, drastically increasing accessibility to group-level dietary assessment.

The purpose of this study was to evaluate the effectiveness of teaching self-instructional skills to navigate to a mobile device to access video prompts to teach novel behaviors to two adults with autism spectrum disorder (ASD) in a vocational setting. This study used a multiple probe across conditions design to evaluate effectiveness. In baseline, the researcher directed the participants to complete a novel task and collected data on correct steps completed. In technology training the researcher used a system of least prompts procedure to teach participants to initiate the use of the mobile device, navigate to an app, navigate to the specific behavior schedule, watch video prompt, navigate to the next step, and complete the modeled behaviors. After mastery of technology training, researcher evaluated performance of novel tasks following self-instruction to access video prompts on the mobile device. Participant’s fidelity of navigation skills was assessed, however was not included in mastery criterion. Both participants learned to self-instruct to independently access video prompts on a mobile device. One participant self-instructed using the mobile device and video prompts to correctly complete novel tasks.

This thesis evaluated the clinical utility of cardiopulmonary computed tomography (CT) in patients presenting with chest pain and dyspnoea. Studies within this thesis confirmed the following. Firstly, there is a requirement for improved diagnostic pathways to minimise patients being discharged without a diagnosis, which currently occurs in 30-40% of patients admitted with chest pain and dyspnoea. Historically, CT has been utilised in 32% of admissions with chest pain and 10% of admissions with dyspnoea. Secondly, challenges exist to the wider adoption of cardiopulmonary CT. These include patient-related factors, institutional capabilities and guideline restrictions. In acute admissions, 11% of patients with dyspnoea and 7% of patients with chest pain and a low to moderate likelihood of CAD are suitable for CT. In the RACPC setting, including patients across the entire spectrum of CAD likelihood, 18% of patients are suitable for CT. NICE CG95 would recommend only 1% of acute chest pain admissions and 2% of RACPC attenders for CT. Thirdly, NICE CG95 would recommend 51% of acute chest pain admissions and 66% of RACPC attenders for discharge without cardiac investigation. In the RACPC population, significant CAD is identified in 10% of these patients and a major adverse cardiac event in 2%. Fourthly, in selected patients with suspected cardiac chest pain, cardiac CT has a diagnostic yield of 21% in acute admissions and 13% in RACPC attenders for significant CAD. In acute admissions with dyspnoea, cardiopulmonary CT has a diagnostic yield of 20% for CAD, 20% for pulmonary embolism, nil for aortic dissection and 89% for non-vascular chest pathology. Fifthly, inclusion of CT in diagnostic pathways for chest pain result in fewer patients discharged without a diagnosis, fewer invasive angiography procedures and reduced diagnostic costs. In patients with dyspnoea, CT provides value to clinicians making diagnoses and supports early discharge without detrimental outcomes.

Esta pesquisa visa analisar a estética do espaço e a estética literária empregadas na narrativa da obra Pôr-do-Sol, de Dazai Osamu, bem como resgatar a essência da cultura japonesa contemporânea de um Japão devastado pela Segunda Guerra Mundial, onde o autor expressa toda a sua sensibilidade poética. Este trabalho baseia-se na pesquisa biográfica de Dazai Osamu, com ênfase ao momento histórico que o autor testemunhou e onde realizou suas escritas, visando o levantamento da iconografia, pictografia e metonímia na linguagem de sua obra. Através deste estudo buscam-se os elementos que o enquadrem no gênero literário denominado Romance do Eu e as influências exercidas pelo Naturalismo europeu e movimentos sociais em sua carreira literária por meio da análise da hereditariedade, das influências do meio social no ambiente da obra e a estética literária empregada em sua técnica narrativa. O estudo desenvolvido demonstra as interferências ocidentais na Literatura Japonesa através da intertextualidade de obras japonesas e ocidentais, que dialogam entre si, e apresentam uma narrativa ao redor da estética do espaço na obra Pôr-do-Sol, retratando a essência humana, o irracional, as emoções, o onírico, as alegrias e desilusões inerentes a todos os seres humanos, principalmente na sociedade japonesa do período histórico do pós-guerra.
This research seeks analyze Dazai Osamu\'s spatial aesthetics and his literary style, which was used in his novel Setting Sun, besides to bring off essence of Japan Contemporary Culture, that was devastated in this country due to World War II. Another point of this study is the narrative aesthetics, where the writer expresses his poetic sensitiveness. This study is based on Dazai Osamu\'s autobiographic research, emphasizing a historical moment of Japan, which he witnessed and finished his writings despite of war; in his novel, Dazai aimed the language of: iconography survey, pictorial survey and metonymy language. This study will search for elements that fit in the literary genre named I Novel, as well as influences the writer suffered from European Naturalism and social movements in his literary carrier; Dazai analyzed the heredity and the influences of social means described in atmosphere of his work and the literary aesthetic (spatial) carried out in his narrative techniques. The study developed here points out western interference in Japanese literature, which can be noticed in the inter-textuality of literary works between west and east, that inter-act itself; therefore introduces a narrative related to spatial aesthetic in the Setting Sun which the writer describes the essence of human beings´nature such as: irrational feelings, the emotions, the day-dreams, the cheerfulness and disappointments, inherent in whole human beings, especially in the Japanese society in certain historical time after war.

The role of hydration in causing or alleviating suffering in patients with advanced cancer is poorly understood and remains controversial. Most dying cancer patients have reduced oral intake in the last days of life. This may be related to symptoms arising from the cancer or its treatment, such as dysphagia, anorexia, nausea, vomiting, or mechanical problems such as bowel obstruction. Accordingly, the subject of clinically assisted hydration (CAH) is emotive amongst patients and their carers, with the omission or withdrawal of CAH potentially viewed as hastening death in some instances. Current hydration assessment methods are limited in cancer patients approaching death. Bioelectrical impedance vector analysis (BIVA) is an accurate validated method of assessing body composition; however its clinical use in advanced cancer is uncertain. This study aims to measure hydration in advanced cancer patients using BIVA, in order, to determine the relationship between symptoms, physical signs and biochemistry. BIVA was used to evaluate hydration in advanced cancer patients within a hospice in the UK. Total body water (TBW) was estimated using the impedance index (Height2/Resistance [H2/R]). Regression analysis determined the predictive properties of clinical variables on H2/R. Assessed items included: performance status (ECOG), symptoms (Burge-4 score), physical signs (Morita Dehydration Score) and biochemistry. Ninety patients participated (recruitment rate = 76.3%). Hydration status was normal in 43 (47.8%), ‘more hydrated’ in 37 (41.1%) and ‘less hydrated’ in 10 (11.1%) patients. A multiple regression analysis was conducted. H2/R was significantly predicted by female gender (Beta = -13.85, p<.001), the Burge-4 score (Beta = -0.29, p=.04), the Morita dehydration score (Beta = -2.55, p=.02) and oedema (Beta = 2.55, p<.001). Median survival was significantly shorter in ‘less hydrated’ patients (44 vs. 68 days; p=.04) and in pre-renal failure (44 vs. 100 days; p=.003). Higher values of H2/R were associated with improved survival (HR=0.98 [95%CI= .96, .99], p=0.01). The results demonstrate that in advanced cancer, hydration status (as measured by H2/R and BIVA) relates to clinically measurable signs and symptoms. Lower TBW volume was associated with female gender and also linked with higher scores for symptoms and physical signs. Higher TBW was associated with oedema. H2/R, BIVA and pre-renal failure were independent predictors of survival. Further work is needed to determine how BIVA can be used to guide the management of fluid states in advanced cancer.

Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul
In the late eighteenth century, Ann Radcliffe established herself as one of the most famous novelists of her time, and she reached the peak of her career with her fourth novel entitled The Mysteries of Udolpho (1794). Although it is one of the most important gothic novels, this narrative has issues not much explored by critics yet. The Mysteries of Udolpho presents us with one of the strongest characteristics of Radcliffe s fiction, namely, the detailed construction of setting. In this sense, this work analyses and discusses the roles of setting, which is organized in the novel as natural or constructed setting. The analysis focuses on the relation between this thematic-formal aspect and the actions and personal relationships of the protagonist Emily with other characters. The discussion shows that the different types of setting are essential in the narrative once they have strong participation in the ideological construction of characters regarding the connection between sentimentalism and rationality. Therefore, the relation between setting and characters, in this particular novel, expresses important aspects of the complex development of the bourgeois sensibility in eighteenth-century England.
Em fins do século XVIII, Ann Radcliffe se estabeleceu como uma das romancistas mais famosas de sua época, atingindo o ápice de sua carreira com seu quarto romance intitulado The Mysteries of Udolpho (1794). Apesar de ser um dos romances góticos ingleses mais importantes, ele ainda apresenta questões pouco exploradas pelos críticos. The Mysteries of Udolpho possui uma das características mais fortes das obras de Radcliffe: a minuciosa elaboração do espaço. Em vista disso, este estudo analisa e discute as funções do espaço, o qual está organizado em natural e construído. A análise centra na maneira como esse aspecto temático-estrutural se relaciona com as ações e relações pessoais da protagonista Emily com as demais personagens. Discutimos como os diferentes tipos de espaço tornam-se essenciais por participarem de forma enfática na construção ideológica das personagens, no que diz respeito à associação entre sentimentalismo e racionalidade. Assim, a relação entre espaço e personagens nesse romance expressa aspectos importantes da complexa construção da sensibilidade burguesa na Inglaterra do século XVIII.

This essay’s aim is to investigate how Rowling uses her novel Harry Potter and the Chamber of Secrets to criticize racism in her magical world and ours. A secondary aim concerns how Rowling’s critical stance creates ways to resist racism for readers in the EFL classroom. Therefore, a comparison from a Critical Race Theory (CRT) perspective is made with focus on certain sequence comparisons between the novel and the film. Teachers need to highlight problems like racism in classrooms and fantasy novels and movies are exceptional tools to raise awareness and teach critical thinking to students.

In the years immediately following the Second World War, the main part of Latvian literature was produced by writers living outside Latvia. To this day Latvian literature continues to be written outside Latvia, albeit to a much smaller extent. This study examines those Latvian novels, written outside Latvia after the Second World War, which depict the realities of the early years of exile. The aim of the study is to describe the image of the world of exile as depicted in these novels. Borrowing from Bakhtin's concept of the chronotope, images relating to time and space in these novels are examined in order to discern a mental topography of exile common to all these novels - a chronotope of exile. The novels are read as part of a collective narrative, produced by a particular social group in unordinary historical circumstances. The novels are regarded as this social group’s common perception of its own experience of this historical reality. The early years of exile fall into two distinct periods: first, the period of flight from Latvia and life in and around the Displaced Persons camps of postwar Germany; second, the early years of settling in a new country of residence after emigration from Germany. A model of the perceived world is constructed in order to compare these two periods, as well as their divergence from a standard perception of oneself in the world. This model consists of various time-spaces radiating concentrically out from the individual – ranging from the physically and psychologically near-lying time-spaces of one’s personal and intimate life, through everyday social time-spaces, as well as formal societal time-spaces, to the more distant abstract and conceptual perceptions of one’s place in the universe. Basic human concepts such as home, family, work, intimate relationships, social administration, and most notably the homeland – Latvia – are plotted at various points within these models. Divergences between the models describing the perception of time and space in the two early periods of exile thus become apparent.

This study examined the effects and efficacy of two vocational instructional interventions - a Hand-Held Computer intervention versus a Staff Model intervention - as vocational instructional tools for high school students with autism and mental retardation. Specifically, the study analyzed the effects of these two treatments on the completion of authentic novel job tasks within a local department store. This research indicated the provision of specific technology as an instructional model positively influenced participants' ability to: accurately complete tasks, exercise increased independence during task completion, reduce problematic behavior during task completion, and lower necessary staff prompts during task completion. The use of technology to support individuals with severe disabilities has the potential to increase their level of independence and accuracy of job completion within community-based settings. Five high school students with autism and mental retardation participated in this study, which compared the use of a palm-top computer with a traditional staff model during the completion of eighteen novel job tasks within various departments of a large department store. Five of eight variables subjected to ANOVA and independent t-test analyses demonstrated significance.
Ph.D.
Department of Child, Family and Community Sciences
Education
Child, Family, and Community Sciences

Allocation of objects or resources to competing agents is a ubiquitous problem in the real world. For example, a federal government may wish to allocate different types of spectrum licenses to telecom service providers; a search engine has to assign different sponsored slots to the ads of advertisers; etc. The agents involved in such situations have private preferences over the allocations. The agents, being strategic, may manipulate the allocation procedure to get a favourable allocation. If the objects to be allocated are heterogeneous (rather than homogeneous), the problem becomes quite complex. The allocation problem becomes even more formidable in the presence of a dynamic supply and/or demand. This doctoral work is motivated by such problems involving strategic agents, heterogeneous objects, and dynamic supply and/or demand. In this thesis, we model such problems in a standard game theoretic setting and use mechanism design to propose novel solutions to the problems. We extend the current state-of-the-art in a non-trivial way by solving the following problems: Optimal combinatorial auctions with single minded bidders, generalizing the existing methods to take into account multiple units of heterogeneous objects Multi-armed bandit mechanisms for sponsored search auctions with multiple slots, generalizing the current methods that only consider a single slot. Strategyproof redistribution mechanisms for heterogeneous objects, expanding the scope of the current state of practice beyond homogeneous objects Online allocation mechanisms without money for one-sided and two-sided matching markets, extending the existing methods for static settings.

Calcium phosphate biocements are inherently brittle materials due to their ceramic nature. Hence, currently applied cement formulations are only indicated for non-load bearing application sites. An approach to reduce cement brittleness is based on the use of cement – polymer composites, which combine the flexibility of a polymeric phase with the hardness and compression strength of a cement matrix. Here, a relatively new strategy is the use of “dual-setting” cements, in which the polymeric phase is simultaneously build up from monomers or prepolymers during cement setting. This approach largely maintains basic properties of the fresh paste such as rheology or setting time. Previous works on such dual setting cements were dealing with a radical polymerization reaction to create the polymeric network. This type of reaction requires the addition of a suitable initiator system (e.g. a tertiary amine in conjunction with ammonium peroxosulfate), which are often cytotoxic and may interfere with the cement setting conditions. The current thesis dealt with alternative strategies, in which the cross-linking and gelation of the second (polymeric or inorganic) cement phase is initiated by the chemical conditions of the setting reaction such that no additional initiator has to be added to the cement paste. In a first approach a six armed star molecule functionalized with isocyanate groups as reactive termini (NCO–sP(EO-stat-PO)) was used to build up a hydrogel matrix, which was then subsequently mineralized with hydroxyapatite nanocrystals following the hydrolysis of incorporated -tricalcium phosphate particles. The stimulus to initiate hydrogel cross-linking are water molecules, which subsequently hydrolyzed isocyanate groups to amines, which then cross-linked with unreacted isocyanate to form urea-bonds. Here, it was possible to show the advantages features of a dual setting system in comparison to the simple combination of hydrogels with unreactive filler particles. By the formation of the cement matrix within the hydrogel a strength improvement by the factor of 30 could be observed. Furthermore, by applying a dual setting system higher mineral concentrations are realizable. The mechanical properties such as elasticity, compression strength and E-modulus of a composite with 30 wt% NCO–sP(EO-stat-PO) were found to be similar to the properties of cancellous bone. With the motivation to develop a dual setting and resorbable cement, a brushite (CaHPO4·2H2O) forming cement was modified with a second inorganic silica based precursor. The latter was obtained by pre-hydrolysing tetraethyl orthosilicate (TEOS) under acidic conditions. This silica precursor was mixed with a cement powder composed of ß-tricalcium phosphate and monocalcium phosphate, whereas cement setting occurred by a dissolution–precipitation process to form a matrix of brushite. Simultaneously, the increase of the pH during setting from initially 1-2 to values > 4 initiated the condensation reaction of the hydrolysed TEOS. This resulted in an interpenetrating phase composite material in which the micropores of the cement were filled with the nanoporous silica gel. This resulted in a higher density and a compressive strength of 24 MPa, which is approximately 5-10 times higher than the CPC reference at the same powder to liquid ratio. The microporous character of the composites also altered the release of vancomycin as a model drug, whereby in contrast to the quantitative release from the CPC reference, approx. 25 % of the immobilised drug remained in the composite matrix. It was also observed, that a variation of the TEOS content in the composite enabled a control over cement phase composition to form either brushite, anhydrous monetite or a biphasic mixture of both. Cytocompatibility tests revealed that composites with the highest silicate content showed an increased cell proliferation compared to the silica-free brushite reference. Proliferation was found to be similar to a hydroxyapatite reference with a significant higher activity per cell. Mechanistically, the improved biological response could not be attributed to the released silicate ions, but to a decreased release of phosphate and adsorption of magnesium ions from the cell culture medium. Finally, an investigated dual setting cement system was based on the combination of a brushite forming cement powder with an aqueous silk fibroin solution. Here, changes of both ion concentration and pH during cement setting were shown to build up an interpenetrating fibroin – brushite composite with combined properties of the elastic polymer and the rigid cement. Mechanistically, the low pH of the cement paste (2) as well as the free Ca2+ ions during setting resulted in a conformation change of the dissolved fibroin from random coil to ß-sheet structure. This leads to a rapid gelation and contraction of the fibroin phase with a self-densifying effect on the cement paste. The set composites showed typical ductile fracture behavior under dry testing conditions and a high elasticity under wet conditions with a mechanical strength nearly an order of magnitude higher than the fibroin free cement reference. Cell number and activity against MG63 cells were strongly increased on silk fibroin cement composite surfaces at later time points, which could be again attributed to a decreased ion release and adsorption compared to the fibroin free cements. This in turn slowed down the in vitro degradation of the CPC phase in such composites
Calciumphosphat-Knochenzemente sind auf Grund ihrer keramischen Struktur inhärent spröde Werkstoffe, weswegen sie gegenwärtig nur für nicht-kraftbelastete Anwendungsbereiche verwendet werden. Ein Ansatz zur Verringerung des spröden Verhaltens basiert auf der Verwendung von Zement – Polymer Kompositen, welche die Flexibilität der Polymerphase mit der hohen Härte und Druckfestigkeit des Zements vereinen. Eine relativ neue Strategie sind dabei sogenannte dual-härtende Zemente, in denen die Polymerphase aus Monomeren bzw. Präpolymeren simultan zur Abbindereaktion des Zements aufgebaut wird. Dieser Ansatz ist insofern vorteilhaft, als dass die grundlegenden Eigenschaften der Zementpaste, wie etwa deren Rheologie oder Abbindedauer, hierbei weitgehend erhalten bleiben. In frühere Arbeiten zu dual-härtenden Knochenzementen wurden die Monomere radikalisch vernetzt. Die dabei notwendigen Initiatorsysteme (z.B. tertiäres Amin und Ammoniumperoxosulfat) sind jedoch zytotoxisch und können zudem mit der Zementreaktion nachteilig interferieren. Die vorliegende Arbeit beschäftigt sich deshalb mit alternativen Lösungstrategien, bei denen die Vernetzung der sekundären (organischen oder anorganischen) Zementphase durch die Reaktionsbedingungen der Zementpaste initiiert wird, sodass kein zusätzlicher Initiator der Paste zugesetzt werden muss. In einem ersten Ansatz wurden Isocanat-modifizierte, sternförmige Präpolymere (NCO–sP(EO-stat-PO)) zum Aufbau der Hydrogelmatrix durch Hydrolyse von zugesetzten α-Tricalciumphosphat Partikeln schrittweise mit Hydroxylapatit Nanokristalliten mineralisiert. Die Vernetzung des Hydrogels in der Paste wurde durch Wasser stimuliert, wobei in einem zunächst Isocyanatgruppen zu Aminen hydrolysiert wurden, die anschließend mit weiterem Isocyanat zu Urethanbindungen reagierten. Hier konnte der Vorteil von dualhärtenden Systemen im Vergleich zu Hydrogelen, denen nichtreaktive Partikel untergemischt werden, gezeigt werden. Durch den Aufbau der Zementmatrix im Hydrogel ergab sich eine um den Faktor 30 erhöhte Festigkeit. Zusätzlich ermöglicht diese Vorgehensweise den Einsatz von erhöhten Mineralgehalten. Die mechanischen Eigenschaften der Komposite mit 30 Gew.% NCO–sP(EO-stat-PO) wie Elastizität, Druckfestigkeit und E-Modul waren dabei vergleichbar mit den Eigenschaften von spongiösem Knochen. Mit dem Ziel einen dualhärtenden, resorbierbaren Zement zu entwickeln, wurde ein Bruschit (CaHPO4·2H2O) bildender Zement mit einer zweiten anorganischen Matrix aus einem silikatischen Precursor modifiziert. Letzterer wurde durch Hydrolyse von Tetraethylorthosilikat (TEOS) unter sauren Bedingungen hergestellt. Das so erhaltene Silicasol wurde anschließend mit dem Zementpulver aus β-Tricalciumphosphat und primärem Calcium-bis-dihydrogenphosphat gemischt, wodurch die Zementreaktion zu Bruschit durch einen Lösungs – Fällungsmechanismus gestartet wurde. Der zeitgleich einsetzende Anstieg des pH-Werts von initial 1-2 auf Werte im Bereich von >4 führt dabei zur Kondensation des Silicasols. Resultat waren interpenetrierende Netzwerke, wobei die Mikroporen der Bruschitzementmatrix mit dem nanoporösem Silicagel gefüllt sind. Dadurch ergibt sich eine höhere Dichte der Zementmatrix und eine mit 24 MPa um den Faktor 5-10 höhere Druckfestigkeit der Komposite gegenüber der Referenz bei gleich bleibendem Pulver-Flüssigkeits-Verhältnis. Der nanoporöse Charakter des Komposites beeinflusst die Freisetzung von Vancomycin als Modellwirkstoff, wobei im Gegensatz zur silicafreien Referenz ca. 25% des Wirkstoffs in der Matrix verblieben. Die Variation des TEOS Gehalts ermöglichte zeitgleich die gezielte Beeinflussung der Zusammensetzung der mineralischen Zementphase mit Bildung von Bruschit, dessen Anhydrid Monetit oder Mischungen aus beiden Verbindungen. Zytokompatibilitätstests an den Kompositen zeigten, dass die höchsten Silicagehalte zu einer verbesserten Proliferation von Zellen auf den Oberflächen gegenüber der silicafreien Referenz führten. Das Zellwachstum war vergleichbar mit einer Referenz aus Hydroxylapatit, wobei deutlich höhere Aktivitäten pro Zelle gemessen wurden. Mechanistisch konnte die verbesserte Zytokompatibilität nicht der Freisetzung von Silikationen zugeordnet werden, vielmehr war eine verminderte Freisetzung von Phosphat und eine geringere Tendenz zur Adsorption von Magnesiumionen aus dem Zellkulturmedium der Grund. Ein abschließender Ansatz bestand aus der Kombination aus einem Bruschit-bildenden Zement und einer wässrigen Seidenfibroin-Lösung. Hier erfolgte der Aufbau der interpenetrierenden Bruschit – Fibroin Netzwerke über den sauren pH-Wert sowie den Anstieg der Ionenkonzentration im System durch die ablaufende Zementreaktion. Somit werden die Eigenschaften des elastischen Polymers und der festen Zementphase erfolgreich kombiniert. Mechanistisch führt dabei der initial saure pH Wert (2) und die während der Reaktion vorhandenen freien Ca2+ Ionen zu einer Konformationsänderung des gelösten Fibroins von eine Zufallsstruktur hin zur β-Faltblattstruktur. Dies führt zur schnellen Gelierung und Kontraktion der Fibroinphase, einhergehend mit einer Selbstverdichtung der gesamten Paste. Die abgebundenen Komposite zeigten typischerweise duktile Brucheigenschaften im trockenen Zustand und eine hohe Elastizität unter wässrigen Testbedingungen, wobei sich um eine Größenordnung höhere Festigkeiten gegenüber der fibroinfreien Referenz ergaben. Zellzahl und Aktivität von MG63 Zellen waren auf den Seidenfibroin-Zementkompositen bei späteren Messzeitpunkten deutlich erhöht, was ebenfalls auf eine geringere Ionenfreisetzung bzw. -adsorption aus dem Medium rückgeführt werden kann. Zeitgleich konnte hierdurch die in vitro Degradation der Zementphase in solchen Kompositen verringert werden

Calcium phosphate cements (CPC) represent valuable synthetic bone grafts, as they are self-setting, biocompatible, osteoconductive and in their composition similar to the inorganic phase of human bone. Due to their long shelf-life, neutral setting and since water is sufficient for setting, hydroxyapatite (HA) forming cements are processed in different paste formulations. Those comprise dual setting, Ca2+ binding and premixed cement systems. With dual setting formulations, both dissolution and precipitation of the cement raw powder occur simultaneously to the polymerization of water-soluble monomers to form a hydrogel. Chelating agents are able to form complexes with Ca2+ released from the raw powder. Premixed systems mostly contain the raw powder of the cement and a non-aqueous binder liquid which delays the setting reaction until application in the moist physiological environment. In the present work, two of those reaction mechanisms allowed the development of HA based cement applications. Drillable cements are of high clinical interest, as the quality of screw and plate osteosynthesis techniques can be improved by cement augmentation. A drillable, dual setting composite from HA and a poly(2-hydroxyethyl methacrylate) hydrogel was analyzed with respect to the influence of monomer content and powder-to-liquid ratio on setting kinetics and mechanical outcome. While the conversion to HA and crystal growth were constantly confined with increased monomer amount, a minimum concentration of 50 % was required to see impressive ameliorations including a low bending modulus and high fracture energy at improved bending strength. Increasing the liquid amount enabled injection of the paste as well as drilling after 10 min of pre-setting. While classic bone wax formulations have drawbacks such as infection, inflammation, hindered osteogenesis and a lack of biodegradability, the as-presented premixed formulation is believed to exhibit outmatching properties. It consisted of HA raw powders and a non-aqueous, but water-miscible carrier liquid from poly(ethylene glycol) (PEG). The bone wax was proved to be cohesive and malleable, it withstood blood pressure conditions and among deposition in an aqueous environment, PEG was exchanged such that porous, nanocrystalline HA was formed. Incorporation of a model antibiotic proved the suitability of the novel bone wax formulation for drug release purposes. Prefabricated laminates from premixed carbonated apatite forming cement and poly(ε-caprolactone) fiber mats with defined pore architecture were presented as a potential approach for the treatment of 2-dimensional, curved cranial defects. They are flexible until application and were produced in a layer-by-layer approach from both components such that the polymer scaffold prevents the cement from flowing. It was demonstrated that solution electrospinning with a patterned collector for the fabrication of perforated fiber mats was suitable, as high fiber volume contents in combination with an appropriate interface enabled the successful fabrication of mechanically reinforced laminates. Mild immersion of the scaffolds under alkaline conditions additionally improved the interphase followed by an increase in bending-strength. Since few years, magnesium phosphate cements (MPC) have attracted increasing attention for bone replacement. Compared to CPC, MPC exhibit a higher degradation potential and high early strength and they release biologically valuable Mg2+. However, common systems offer some challenges while using them in non-classic cement formulations such as the need for foreign ion supply, the potential acidity of the reaction or the fast setting kinetics. Here, it was possible to develop a chelate-setting MPC paste with a broad spectrum of potential applications. The general mechanism of the novel setting principle was tested in a proof-of-principle manner. The cement paste consisted of farringtonite with differently concentrated phytic acid solution for chelate formation with Mg2+ from the raw powder. Adjusting the phytic acid content and adding a magnesium oxide as setting regulator to compensate its retarding effect resulted in drillable formulations. Additionally, there is a strong clinical demand for well working bone adhesives especially in a moist environment. Mostly the existing formulations are non-biodegradable. Ex vivo adhesion of the above presented MPC under wet conditions on bone demonstrated over a course of 7 d shear strengths of 0.8 MPa. Further, the hardened cement specimens showed a mass loss of 2 wt.% within 24 d in an aqueous environment and released about 0.17 mg/g of osteogenic Mg2+ per day. Together with the demonstrated cytocompatibility towards human fetal osteoblasts, this cement system showed promising characteristics in terms of degradable biocements with special application purposes
Calciumphosphatzemente (CPC) stellen ein bedeutsames Knochenersatzmaterial dar, da sie selbstabbindend, biokompatibel, osteokonduktiv und der anorganischen Komponente humanen Knochens ähnlich sind. Durch ihre Lagerstabilität, neutrale Abbindereaktion und da Wasser zum Abbinden ausreicht, werden Hydroxylapatit (HA) bildende Zemente in dual abbindenden, Ca2+ chelatisierenden und vorgefertigten Zementen, verarbeitet. Bei dual abbindenden Formulierungen findet die Lösungs-Fällungs-Reaktion zeitgleich zur Polymerisation wasserlöslicher Monomere zu einem Hydrogel statt. Chelatbildner können mit aus dem Rohpulver freigesetzten Ca2+ Komplexe bilden. Vorgefertigte Zemente enthalten eine nicht-wässrige Trägerflüssigkeit, welche die Abbindereaktion bis zur Anwendung des Zements im feuchten Milieu verzögert. In der vorliegenden Arbeit wurden zwei dieser Reaktionsmechanismen zur Entwicklung HA basierter Anwendungsformen eingesetzt. Bohrbare Zemente sind von klinischem Interesse, da die Qualität einer Schrauben- oder Plattenosteosynthese durch Augmentation mit Zement verbessert werden kann. Bei einem bohrbaren, dual abbindenden Komposit aus HA und einem Poly-2-Hydroxyethylmethacrylat Hydrogel wurde der Einfluss des Monomergehalts und des Pulver-zu-Flüssigkeits-Verhältnisses auf die Abbindekinetik und mechanischen Eigenschaften untersucht. Während die Umwandlung zu HA und das Kristallwachstum mit zunehmendem Monomergehalt reduziert wurden, war eine minimale Konzentration von 50 % nötig, um signifikante Verbesserungen des Bruchverhaltens im Sinne eines niedrigen Biegemoduls und einer hohen Bruchenergie bei gesteigerter Biegefestigkeit nachzuweisen. Wurde der Flüssigkeitsgehalt erhöht, so konnte die Paste injiziert und nach 10 min des Abbindens gebohrt werden. Während klassische Knochenwachsformulierungen Infektionen, Entzündungen, gehinderte Knochenneubildung und mangelhafte Bioabbaubarkeit vorweisen, zeigt die hier dargestellte Formulierung überlegene Eigenschaften. Sie bestand aus HA-Rohpulvern und einer nicht-wässrigen, mit Wasser mischbaren Trägermasse aus Polyethylenglycol (PEG). Es wurde gezeigt, dass das Wachs kohäsiv und knetbar ist und Blutdruckbedingungen standhält. Bei Kontakt mit einer wässrigen Phase wurde das PEG diffusiv mit Wasser ausgetauscht, so dass ein poröser, nanokristalliner HA präzipitierte. Die Einbettung eines Modell-Antibiotikums bestätigte zudem die Eignung des neuartigen Wachses als Wirkstoffdepot. Als eine mögliche Behandlung von 2-dimensionalen, gekrümmten Defekten der Schädeldecke wurden präfabrizierte Laminate aus lagerstabiler, Carbonatapatit bildender Zementpaste und Polycaprolakton-Fasermatten mit definierter Porenarchitektur vorgestellt. Diese sind bis zu ihrer Anwendung flexibel und wurden durch einen schichtweisen Aufbau aus beiden Komponenten erzeugt, so dass der Polymerscaffold den Zement am Zerfließen hindert. Es wurde gezeigt, dass die Herstellung makroporöser Fasermatten durch Elektrospinnen aus der Lösung mittels eines perforierten Kollektors geeignet war, da der hohe Faservolumengehalt und angemessene Grenzflächeneigenschaften die erfolgreiche Herstellung mechanisch verstärkter Laminate ermöglichte. Bei milder Behandlung der Scaffolds mit alkalischer Lösung wurden die Grenzflächeneigenschaften weiter verbessert, was zu einer Steigerung der Biegefestigkeit führte. Seit einigen Jahren geht der Trend der Knochenzementforschung immer stärker in Richtung von Magnesiumphosphatzementen (MPC), da diese verglichen mit CPC ein erhöhtes Degradationspotential, eine hohe initiale Festigkeit, sowie die Freisetzung biologisch wertvoller Mg2+ aufweisen. Jedoch stellen gängige Systeme hohe Anforderungen bei der Verwendung in nicht-klassischen Zementen wie z.B. der Bedarf an Fremdionen und die saure sowie schnelle Abbindereaktion. Dennoch war es möglich, einen chelatisierenden MPC zu entwickeln, welcher ein breites Spektrum an möglichen Anwendungsformen bot. In einer Machbarkeitsstudie wurde untersucht, ob das Abbindeprinzip funktioniert. Die Paste bestand aus Farringtonit und unterschiedlich konzentrierter Phytinsäure. Diese sollte mit freigesetzten Mg2+ komplexieren. Durch Anpassung der Phytinsäurekonzentration und Zugabe von Magnesiumoxid als Abbindemodulator wurden bohrbare Formulierungen erhalten. Neben der Bohrbarkeit sind auch adhäsive Eigenschaften der Zemente im feuchten Milieu von klinischem Interesse, wobei kommerziell erhältliche Systeme meist nicht bioabbaubar sind. Daher wurde die ex vivo Klebehaftung dieses MPC nach 7 d unter nassen Bedingungen auf Knochen analysiert, wobei sich eine Abscherfestigkeit von 0.8 MPa ergab. Des Weiteren zeigten diese Zemente einen Masseverlust von 2 Gew.% innerhalb von 24 d in wässriger Umgebung, sowie die Freisetzung von 0.17 mg/g an osteogenen Mg2+ pro Tag. Zusammen mit der bestätigten Zytokompatibilität bezüglich humaner fetaler Osteoblasten ist dieses System vielversprechend für die Anwendung als abbaubarer Biozement für unterschiedliche klinische Zwecke

The process of metaphrasis denotes the translation of a work of art from one medium into another. Opera is fundamentally an adaptive art form and contemporary opera has increasingly turned to the novel as the sophistication and range of the resources of modem music theatre have expanded. This dissertation will examine the contemporary operatic adaptation of five works of fiction. The method employed is a comparison of fictional and operatic discourse and an analysis of the translation of fictional narrative into operatic narrative. Emily Bronte's Wuthering Heights poses particular narrative problems for operatic adaption while Herman Melville's Billy Budd is characterised by its intrusive narrator and a pervasive ambiguity. Joseph Conrad's novel, Under Western Eyes, exemplifies many of the narratological complexities of modernism, whereas Patrick White's Voss, a seminal postcolonial text, offers the operatic adaptor opportunities for the transcendence of language through music. The final chapter of this study will examine Henry James's tale, liThe Aspern Papers II , which incorporates many of James's reflections on literature and the literary life. The postmodernist operatic adaptation transmutes this self-reflexive fictional work into an opera profoundly concerned with the ontology of opera itself. This study will test the thesis that opera's affinity lies with the novel rather than with drama: that the fundamental narrative mode of opera is diegetic rather than mimetic. The main theoretic thrust proposes that the orchestra in opera performs a similar function to the narrator in fiction. As fictional characters exist only through the medium of their 'text' therefore, it will be argued, operatic characters exist only as part of their 'musical' text. Fictional narrative, while frequently conveying the impression of mimesis is essentially diegetic; operatic characters appear to possess a similar autonomy to their counterparts in drama, but can be seen as analogous to those in fiction and as a function of the diegesis of operatic narrative. Operatic characters are 'created' by the orchestral-narrator and have their being only as part of this narrative act.
Thesis (Ph.D.)-University of Natal, Durban, 1994.

RATIONALE: A low cost point of care test (POCT) to diagnose hepatitis C virus (HCV) viremia could be a critical step toward HCV elimination. The aim of this study is to inform the limit of detection (LOD) for an affordable POC test. METHODS: This study analyzed a convenience sample of cross-sectional HCV testing data from reference laboratories and clinical research studies in 9 countries. Participants of all ages with quantified HCV viremia were included. We analyzed the distribution of HCV viral load for the first detectable HCV RNA available, and derived the clinical sensitivity for a POCT with an LOD of 3 log IU/mL. Bivariate and multivariate analyses were then performed to identify demographic and clinical characteristics associated with low-level viremia (< 3 log IU/mL). RESULTS: The dataset included 53,295 participants from Cambodia, Canada, Cameroon, Georgia, Indonesia, Malaysia, Pakistan, Thailand, and Vietnam. Log HCV RNA was normally distributed, and ≥ 3 log IU/mL corresponded with clinical sensitivity of 98%. Neither HIV co-infection nor cirrhosis were significantly associated with low-level viremia, whereas bivariate analyses showed increased odds of 2.47 (95% CI 2.04, 2.99) for low-level HCV RNA among those ≤ 30 years old compared to those > 30, and an OR of 1.17 (1.02, 1.34) among females compared to males. Stepwise multivariate regression found no significant confounding. CONCLUSION: In this global dataset, a POCT with a LOD of 3 log IU/mL would identify 98% of chronic HCV infections. The increase OR among those ≤ 30 years old year olds is likely explained by a greater frequency among younger persons of recent infection, where fluctuating viremia is well described. A POCT for HCV that could identify persons with 3 log IU/mL or greater would likely facilitate affordable product development and expand the reach of HCV testing in resource-limited settings.
2019-03-17T00:00:00Z

INTRODUCTION: Recently, the faculty from the Department of Family Medicine in conjunction with the Vertical Integration Group at Boston University School of Medicine (BUSM) developed the Finding Information Framework or FIF to assist medical students in building skills utilizing Evidence Based Medicine (EBM). The FIF is an educational algorithm that guides students on how to ask a clinical question and then assists them in finding the most appropriate online resource. This past year, together with the Division of Graduate Medical Sciences and the Alumni Medical Library, the FIF tool was developed into an EBM mobile application (app) to help the students transition from their second to third year of medical school, where they transition from a more didactic to clinical curriculum. This current study aims to assess the aesthetics as well as functionalities of the FIF mobile app by surveying current medical students. METHODS: The author presented initial outlines of the survey to the research team following a review of relevant studies. From this, the final survey was created and submitted for Boston University (BU) Institutional Review Board Approval (IRB) for a study on human subjects. A recruitment email, requesting volunteers to participate in the survey study, was sent to the third and fourth year medical students. RESULTS: Data were categorized into four sections: (1) preliminary questions, (2) app-specific questions, (3) clinical questions, and (4) open-ended questions. Survey results were divided into two parts: part one was with a mixed population and part two was exclusively for third and fourth year medical students. Ease of use and aesthetic appeal generally received higher scores than potential future use of the app. Clinical question responses varied significantly. DISCUSSION: The survey assessing the FIF mobile app shed light into potential areas that the research team should address in further improvements to the app. These areas include easier log-in, preferably earlier in the app to assure easier access to databases, and the option to go directly to a specific known resource without requiring movement through the decision tree if desirable. A major limitation of the study was the small sample size. Further studies would help in further validating the results gained in this study.

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2015
Sickle cell disease represents a major public health problem, especially in Africa, where most of the cases occur. The characteristic feature of the condition is the occurrence of the abnormal hemoglobin S, which polymerizes. Affected individuals may display severe complications, often leading to early death. Therefore, they need to be properly identified to start a treatment as early as possible. However, currently available laboratory diagnostic methods are not feasible in resource-limited settings, since they are time-consuming, usually require expertise and expensive equipment and consumables, and do not allow point of care testing. Thus, there is an urgent need for a reliable low-cost diagnostic test. Some new approaches are under development to overcome this issue. This review summarizes existing methods and new approaches for the diagnosis of the disease and gives the background for my on-going study to use the birefringence of polymerized hemoglobin S to develop a novel diagnostic method (work in progress). An optical assay able to detect light depolarization of haemoglobin S may not only give the diagnosis, but may eventually serve as a novel clinical parameter to assess disease severity.
A doença de células falciformes constitui um importante problema de saúde pública, principalmente em África, onde ocorre a maioria dos casos. Esta doença caracteriza-se pela presença de uma variante da hemoglobina normal, a hemoglobina S, que polimeriza. Estes doentes podem apresentar complicações graves, que frequementemente conduzem a morte prematura. Consequentemente, precisam de ser identificados adequadamente para iniciarem o tratamento o mais cedo possível. No entanto, os métodos diagnósticos laboratoriais disponíveis actualmente não são aplicáveis em regiões com poucos recursos, uma vez que requerem tempo, experiência e equipamentos e consumíveis caros e não permitem realizar o teste no local onde o doente é atendido. Deste modo, há uma necessidade urgente de um teste diagnóstico de baixo custo. Novos métodos estão a ser desenvolvidos para ultrapasssar este problema. Esta revisão aborda os métodos existentes e novas técnicas para o diagnóstico da doença e apresenta o meu projecto em curso de um novo método de diagnóstico utilizando a propriedade de birefringência dos polímeros de hemoglobina S (trabalho em densenvolvimento). Um método óptico capaz de detectar a depolarização da luz pela hemoglobina S poderá não só permitir o diagnóstico, mas também eventualmente constituir um novo parâmetro clínico para avaliar a gravidade da doença.

This dissertation investigates the extent and type of influence the Shona folktale has had on the writing of the Shona novel. Of particular interest is how much influence the folktale has had on the early writers of Shona novels as compared to the modern writers. The study investigates folktale influence on the development of plot, setting and characterisation in targeted novels. With regard to the development of plot, the study focuses on folktale influence on the following aspects; the exposition, complication, climax and resolution. Looking at setting, the study investigates folktale influence on setting as place, time or social circumstances in which the stories happen. The study also investigates the type of characters the novelists portray and seek to detect any folktale influence on characterisation.
African Languages and Literature
Thesis (M.A.)

Waterborne pathogenic organisms including bacteria, viruses, protozoa and helminths, are responsible for a series of diseases which is a major public health concern worldwide. This issue is extremely severe in developing regions due to the scarcity of clean water supply and poor sanitation. Therefore, point-of-use (POU) detection and quantification processes as well as a monitoring program of waterborne pathogens are needed to ensure the safety of water and protect human health. However, the polymerase chain reaction (PCR) technology and its related detection platforms rely on complicated thermal cycling, centralized laboratory equipment and trained personnel, thus making PCR-based systems incapable of POU testing of environmental waters. In this dissertation, we develop a portable 3D-printed system with super-absorbent polymer (SAP) microspheres for sample enrichment, and a membrane-based in-gel loop-mediated isothermal amplification (mgLAMP) system for absolute quantification of pathogens. We also explored the interactions between microbial indicator of Escherichia coli (E. coli) and waterborne pathogen Vibrio Cholerae (V. Cholerae). The main results are as follows:

1. The application of detection and quantification methods is often hindered by the low pathogen concentrations in natural waters. Rapid and efficient sample concentration methods are urgently needed. Here we present a novel method to pre-concentrate microbial pathogens in water using a portable 3D-printed system with super-absorbent polymer (SAP) microspheres, which can effectively reduce the actual volume of water in a collected sample. The SAP microspheres absorb water while excluding bacteria and viruses by size exclusion and charge repulsion. The 3D-printed system with optimally-designed SAP microspheres could rapidly achieve a 10-fold increase in the concentration of E. coli and bacteriophage MS2 within 20 minutes with concentration efficiencies of 87% and 96%, respectively. Fold changes between concentrated and original samples from qPCR and RT-qPCR results were found to be 11.34-22.27 for E. coli with original concentrations of 10⁴-10⁶ cell·mL^-1; and 8.20-13.81 for MS2 with original concentrations of 10⁴-10⁶ PFU·mL^-1. Furthermore, SAP microspheres can be reused 20 times without performance loss thereby significantly decreasing the cost of our concentration system.

2. Following sample concentration, accurate quantification methods for waterborne pathogens are needed, especially at the point of sample collection. The surge of COVID-19 in late 2019 called for a more urgent need for a rapid and cost-effective quantification of SARS-CoV-2 in environmental waters. Quantification results contribute to wastewater-based epidemiology (WBE) which helps the monitoring of prevalent infections within a community and early detections of contamination. Here we demonstrated the usage of our portable membrane-based in-gel loop-mediated isothermal amplification (mgLAMP) system for absolute quantification of SARS CoV-2 in wastewater samples within a one-hour timeframe for point-of-use (POU) testing and data management. The limit of detection (LOD) of mgLAMP for SARS-CoV-2 quantification in Milli-Q water was observed to be down to 1 copy/mL, and that in surface water collected from Kathmandu, Nepal was down to 100 copies/mL. Both were 100-fold lower than that of RT-qPCR in corresponding matrices. Compared to alternative detection methods, our platform has a very high level of tolerance against inhibitors thanks to the restriction of the hydrogel matrix. This enables the highly sensitive detection in either clinical or environmental samples.

3. Regular environmental surveillance of waterborne pathogens is key to ensure the safety of water and protect public health. Due to the diversity of pathogenic bacteria in environmental waters, regular monitoring of so many pathogens for individuality is impractical. Therefore, microbial indicators are used to gauge the total pathogen concentration; and manage waterborne health risks. In this study, the interactions of V. cholerae, the etiologic agent of reemerging cholera, with E. coli, the most commonly used indicator for waterborne pathogens. Specifically, we investigated through evaluating the survival and growth of both bacteria under different temperature and nutrition deprivation using plate culturing and real-time polymerase chain reaction (qPCR). During co-growth, it was challenging for V. Cholerae to maintain initial population advantages as E. coli consumes nutrition more effectively. Whereas during co-existence, V. Cholerae soon fell into a viable-but–non-culturable state under environmental stress in 3-5 days while E. coli stay viable more than 14 days. We found that V. cholerae interacts with E. coli differently depending on the composition of the water that is sampled and analyzed. This suggests that bacterium-bacterium interactions influenced by the intrinsic chemical and biological parameters of ambient water will be a contributing mechanism in regulating the proliferation of V. cholerae.

In summary, two platforms for environmental sample concentration and detection have been developed and tested using ambient and engineered waters. In addition, interactions between a microbial indicator, E. coli, and the pathogenic bacteria, V. Cholerae, were studied. The chapters in this thesis describe in detail: (1) A hand-pressed 3D-printed system to produce SAP microspheres was developed with the goal of achieving efficient concentrations of environmental microorganisms for subsequent analysis. The simplified concentration procedure and can be easily integrated into various detection platforms; (2) A portable membrane-based in-gel loop-mediated isothermal amplification (mgLAMP) system was developed for absolute quantification of SARS-CoV-2 in environmental water samples within one hour, enabling a 100-fold lower detection limit compared to the gold-standard of RT-qPCR; and (3) Differences in bacterium-bacterium interactions of V. cholerae and E. coli under as a function of water composition indicated that environmental stress presented in ambient water matrices should be taken into consideration while using a microbial indicator such as E. coli to estimate the risk of waterborne pathogens. These collective advances allow for the rapid and ultrasensitive POU testing of waterborne pathogens that should provide for more effective monitoring strategies in terms of the use of indicator microorganisms.

Background: There is currently no standard method of diagnosing the presence or severity of concussion in acute primary care settings. This pilot project is part of a larger study to develop a Computerized Concussion Assessment Tool (CCAT). Methods: A prospective observational clinical study was conducted to explore the validity of the CCAT among patients presenting to the Emergency Department at Kingston General Hospital and at Hotel Dieu Hospital (Kingston, Ontario) with minor head injury. Twenty-two patients with concussion and eighteen patients with head injury (but not diagnosed with concussion) were recruited to the study. All participants completed a background questionnaire, several neurocognitive tests and the CCAT assessment. Performance on the CCAT was compared between these two groups. Data collected during the development phase of the CCAT from a Normal Volunteers group (n=68) were used in an additional comparison. CCAT Scores for Selective Attention, Divided Attention and Memory were compared with standard neurocognitive tests through correlational analyses. In addition, the validity and clinical yield of the CCAT were investigated relative to gold standard measures. Results: After adjustment for covariates, no statistically significant differences were found between the three participant groups for any of the three primary CCAT Scores (Selective Attention, Divided Attention and Memory). Correlational analyses showed that the CCAT Selective Attention Score and the CCAT Memory Score are moderately correlated with standard neurocognitive tests. There was no correlation observed for the CCAT Divided Attention Score and its associated neurocognitive test. Conclusion: The CCAT was unable to discriminate between concussed patients and non-concussed individuals. However, moderate correlations observed between the CCAT Scores for Memory and Selective Attention and their respective neurocognitive tests support a view that there should be optimism for the future development of the CCAT. Issues related to the feasibility of the study and its administration in the emergency department setting are discussed.
Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2008-09-23 10:40:20.199

Early written Shona narratives like Solomon Mutswairo's Feso [Thorn; name of main character, 1982] evince fantasy since they emanated from folktales, a genre that abounds in this element. Contrary to this, Charles Mungoshi attempts to portray life faithfully in Makunun'unu Maodzamwoyo [Brooding breeds despair, 1977], Ndiko Kupindana Kwamazuva [How time passes, 1975] and Kunyarara Hakusi Kutaura? [Is silence not a form of speech? 1983]. This study attempts to show how this realism manifests itself in the components that constitute each of the works: setting, plot, characterisation, theme and style. Mungoshi's characters, for instance, are not one-sided supernatural beings who perform fabulous acts. Instead, they have strengths and limitations like people in everyday life. Their actions and speech are consistent with their social backgrounds. By injecting realism into the Shona narrative, Mungoshi has contributed towards its development. Due to this realism, the works deserve the label "novels" as opposed to "romances".
African Languages
M.A. (African languages)

Trabalho de Projeto do Mestrado Integrado em Engenharia Biomédica apresentado à Faculdade de Ciências e Tecnologia
Um cimento ósseo é um material biocompatível endurecível usado para preencher defeitos ósseos que deve possuir características parecidas com os tecidos ósseo e dentário. Os cimentos à base de fosfatos de cálcio disponíveis revelam alta microporosidade (permite a deposição de moléculas biológicas e o escoamento de nutrientes/lixos metabólicos) e têm “parecenças” químicas à hidroxiapatite de cálcio do osso. No entanto, revelam baixa eficiência mecânica (para aplicação em áreas de carga elevada) e baixa macroporosidade (para migração de osteoblastos e consequente regeneração óssea).Diferentes formulações de cimentos à base de fosfato de cálcio/gelatina fora produzidos incorporando pedaços altamente porosos de poli(ε-caprolactona)/nanopartículas de sílica (92:8 % m/m) (aditivados com glicofurol, um agente porogénico, compatibilizante de polímero/inorgânico e plastificante) processados por uma técnica de foaming/mistura assistida por dióxido de carbono supercrítico. Estes biomateriais foram produzidos de maneira a melhorar as propriedades morfológicas (tais como área de superfície, macroporosidade e densidades aparente e real), mecânicas (módulo de Young e força de compressão à rutura) e de compatibilidade dos cimentos ósseos produzidos. A composição dos pedaços produzidos pela técnica de foaming/mistura assistida por dióxido de carbono supercrítico a serem incorporados nos cimentos à base de fosfato de cálcio/gelatina foi investigada. As propriedades morfológicas e mecânicas dos cimentos ósseos produzidos foram avaliadas e ensaios de hemocompatibilidade e libertação de um fármaco osteogénico (dexametasona) foram realizados.Foi concluído que os cimentos ósseos produzidos são rapidamente endurecíveis (~7,5 minutos). A alta composição mássica percentual dos pedaços produzidos pelo método de foaming/mistura supercrítico (12 m/m %) não melhorou diretamente as propriedade dos cimentos ósseos. No entanto, alguns dos cimentos ósseos produzidos mostraram valores superiores de propriedades mecânicas (tais como 45 MPa e 2.1 MPa para o módulo de Young e força de compressão à rutura, respetivamente) e porosidade (>70%) (particularmente revelando alta macroporosidade) quando comparados com outos cimentos de fosfato de cálcio comerciais (tais como Ostim® e ChronOS®Inject). Foi também concluído que os cimentos ósseos produzidos são capazes de libertar dexametasona até 21 dias, o que é considerado pela literatura como um intervalo de tempo adequado para estímulo da regeneração óssea.Conclui-se que os cimentos ósseos produzidos são candidatos para enchimento de defeitos de osso/dentes, no entanto mais pesquisa deve ser realizada a formulações de cimentos de fosfato de cálcio, particularmente à percentagem de composição mássica dos pedaços produzidos pelo método de foaming/mistura supercrítica.
Bone cement is a biocompatible setting biomaterial used for bone defect fill that must have similar features to bone and dental tissues. Available calcium phosphate-based bone cements reveal high microporosity (enable deposition of biological molecules and nutrients/metabolic wastes flow) and have higher chemical similarities to bone calcium hydroxyapatite. However, they reveal low mechanical performance (to high load-bearing application areas) and low macroporosity (for osteoblast migration and consequent bone regeneration).Different formulations of calcium phosphate/gelatine-based bone cements were produced incorporating highly porous pieces of poly(ε-caprolactone)/silica nanoparticles (92:8wt.%) (additivated with glycofurol, a porogenic, polymer/inorganic compatibilizer and plasticizer agent) processed by supercritical carbon dioxide-assisted foaming/mixing method. These biomaterials were produced in order to enhance morphological (such as surface area, macroporosity and bulk and real densities), mechanical (Young’s modulus and compressive strength at break) and compatibility properties of the produced bone cements. The composition of pieces produced by supercritical foaming/mixing method to be incorporated into the calcium phosphate/gelatine-based bone cements was investigated. Morphological and mechanical properties of the produced bone cements were evaluated and hemocompatibility and osteogenic drug release (dexamethasone) assays were also performed. It was concluded that the produced bone cements are fast-setting (~7.5 minutes). The higher weight percent composition of pieces (12 wt.%) produced by supercritical foaming/mixing method did not directly enhance the properties of the bone cements. However, some of the produced bone cements showed higher values of mechanical properties (such as 45 MPa and 2.1 MPa for Young’s modulus and compressive strength at break, respectively) and porosity (>70%) (particularly, revealing high macroporosity) when compared to other commercial calcium phosphate cements (such as Ostim® and ChronOS®Inject). It was also concluded that the produced bone cements are able to release dexamethasone for an estimated period of 21 days, which is considered by the literature as a suitable time interval to stimulate bone regeneration.It was concluded that the produced bone cements are candidates for bone/dental defect fillers, however more research should be performed to calcium phosphate cement formulations, particularly on the weight percent composition of pieces produced by supercritical foaming/mixing method.