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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Prevalensen av HPA1a-negativa blodgivare i Jönköpings- och Östergötlands län med flödescytometrisk fenotypning

Karlsson, Christina, Fredriksson, Liza January 2019 (has links)
Humana trombocytantigen (Human Platelet Antigens, HPA) är genetiska polymorfismer som uttrycks på trombocyters membranglykoproteiner. Om icke-kompatibla trombocytantigen införs i blodcirkulationen kan alloimmunisering uppstå där antikroppar produceras mot främmande antigen, det kan därför vara av betydelse att registrera blodgivares antigen. Studiens syfte var att utvärdera prevalensen av HPA1a-negativa blodgivare i Jönköpings- och Östergötlands län med hjälp av flödescytometrisk fenotypning. Studien inkluderade totalt 300 blodgivare, varav 150 från Jönköpings län och 150 från Östergötlands län. Fluorokrommärkta antikroppar riktade mot CD42a och CD61 användes för att detektera HPA1a-negativitet med flödescytometrisk metod. I Jönköpings län detekterades fyra (2,7 %) HPA1a-negativa blodgivare och i Östergötlands län detekterades sex (4,0 %) HPA1a-negativa blodgivare. Statistisk analys visade ingen signifikant skillnad mellan antal HPA1a-negativa blodgivare i de undersökta länen. Länens prevalens av HPA1a-negativitet motsvarade den genomsnittliga prevalensen i Sverige och nya HPA1a-negativa blodgivare har registrerats vilket är en viktig tillgång då patienter är i behov av trombocytkoncentrat. Då studien begränsades av dess ringa storlek samt att kvinnor exkluderats bör vidare studier med större populationer och fler län i Sverige utföras.
362

Metodverifiering av ny upparbetningsmetod för kolhydratfattigt transferrin

Ulin, Desirée January 2019 (has links)
Transferrin är ett protein som har uppgiften att transportera järn i kroppen. Transferrin är ett glykoprotein med två kolhydratkedjor med två, tre förgreningar med terminala sialinsyror. Antalet sialinsyror ger proteinet olika isoformer och benämns därefter, så som tetrasialotransferrin som har fyra terminala sialinsyror och är den vanligaste förekommande isoformen. Disialotransferrin används som en biokemisk markör för att identifiera individer som har en hög alkoholkonsumtion under en längre period. Disialotransferrin ökar i koncentrationen vid hög alkoholkonsumtion under minst 14 dagar. Den benämns som kolhydratfattigt transferrin (eng. Carbohydrate-Deficient Transferrin, CDT) och analyseras med jonbyteskromatografi. Referensvärdet för CDT är > 2,0 % då en individ har ett alkoholmissburk. Syftet med studien var att undersöka om svarstiden går att förkorta genom att optimera upparbetningen av prover och sedan utföra en metodverifiering. Optimeringen av upparbetningen omfattade en kortare inkuberingstid från nästan ett dygn till 60 minuter, förenklad tillsättning av fällningsreagens och förändrad centrifugering av proverna. I ett inledande försök analyserades 25 serumprover med olika varianter av optimerad upparbetning och resultatet jämfördes mot standardmetoden. Metodverifieringen bestod av analys av 35 serumprover med den nya upparbetningsmetoden vilket jämfördes mot standardmetoden. I analysen jämfördes även precisionen för låg (1,4 % CDT) och hög (3,2 % CDT) kontroll samt två patientprover med ett låg och hög halt av disialotransferrin med den nya metoden. Precisionen för den låga kontrollen och patientprov 1 (CV=18,05 %) visade sig var sämre än för den höga kontrollen och det patientprov 2 (CV=5,79 %). Analys av de 35 proverna visade att det var en bra överensstämmelse mellan metoderna; korrelationskoefficienten var 0,997 och ett parat t-test kunde inte detektera någon statistik signifikant skillnad mellan proverna (95 % konfidensnivå). På grund av den sämre precisionen för låga koncentrationer av disialotransferrin behöver dock den nya upparbetningsmetoden utvärderas ytterligare. Däremot är det bestämningen av CDT-halten runt 2 % som är viktig och den nya metoden har inte sämre variationskoefficient (CV %) än standardmetoden.
363

Middle School Students’ Conceptualization of Science Classroom Belonging Between Curricular Contexts

Temitope F Adeoye (6636410) 10 June 2019 (has links)
The purpose of this study was to examine belonging at classroom and academic domain levels, extending research that has primarily investigated general school and classroom-level belonging. This examination accounts for the context-specific, instructional, and domain experiences of students’ belonging. More specifically, the goals of the research were to investigate the relations between belonging in science class with engagement, and to contrast students’ perspectives of science classroom belonging in traditional compared to inquiry curricular contexts. Middle school students from traditional and inquiry science contexts completed self-reported measures of science classroom belonging and science engagement. Semi-structured interviews were conducted to evaluate students’ experiences of belonging in science class. Science classroom belonging was correlated with science engagement, with students from inquiry contexts reporting higher belonging and engagement quality. In both contexts, students reported common social, academic and contextual sources of belonging, with additional emphasis on content-based and interpersonal interactions. In comparing justifications between contexts on the role of competence for experienced belonging, students in traditional contexts reflected on self-focused, intrapersonal competence, while students in inquiry contexts reflected on interpersonal forms of competence. Students’ differentiated reports and conceptualization of belonging were related to contextual supports for involvement in authentic disciplinary practice and peer responsiveness.
364

Introducing the dilemma of societal alignment for inclusive and responsible research and innovation

Bengtsson, Lars, Ribeiro, Barbara, Benneworth, Paul, Bührer, Susanne, Castro-Martínez, Elena, Hansen, Meiken, Jarmai, Katharina, Lindner, Ralf, Olmos-Penuela, Julia, Cordula, Ott, Shapira, Philipp January 2018 (has links) (PDF)
In this discussion paper, we outline and reflect on some of the key challenges that influence the development and uptake of more inclusive and responsible forms of research and innovation. Taking these challenges together, we invoke Collingridge's famous dilemma of social control of technology to introduce a complementary dilemma that of "societal alignment" in the governance of science, technology and innovation. Considerations of social alignment are scattered and overlooked among some communities in the field of science, technology and innovation policy. By starting to unpack this dilemma, we outline an agenda for further consideration of social alignment in the study of responsible research and innovation.
365

Evaluation of environmental samples as a sampling method for detecting pathogens in zebrafish

Lacorazza, Camila January 2019 (has links)
Zebrafish are becoming increasingly popular to use in different kinds of research projects as research animals, replacing rodents in many fields. When using animals for research, it is important to keep track of the animal health in order to get reliable results. The purpose of the study was to investigate whether these pathogens could be found analyzing environmental materials with real-time PCR instead of euthanizing fish and submitting them for histopathology. Also, to see if any material differentiated from the rest regarding accessibility to work with in a routine diagnostic laboratory.     This study was performed on environmental samples, such as filters, swabs, detritus and water, from a recirculating water system holding zebrafish. The pathogens analyzed were Mycobacterium chelonae, M. haemophilum, M. abscessus, M. marinum, M. fortuitum and Pseudoloma neurophilia, all common pathogens that can affect zebrafish.     All materials tested gave at least one positive result for most of the pathogens tested. Two pathogens were not detected, M. marinum and M. abscessus. Due to poorly working PCR-system for M. fortuitum, the results for that bacteria were deemed inconclusive. The filter materials and the swabs of the filter materials gave the best results in this small study, although all materials gave satisfactory results. In conclusion this study shows that environmental samples can be used to detect pathogens in zebrafish, but larger studies should be performed to better evaluate which material is the best one to use.
366

Retrospective serological and virological survey of influenza D virus among cattle in Sweden

Ahlgren, Evelina January 2019 (has links)
Respiratory diseases in cattle can cause economic losses due to the decreased dairy and meat production. Virus is the main reason for these diseases. Symptoms can be fever, cough and nasal discharge.     Influenza are a group of viruses belonged in the Ortomyxoviridae family. The big influenza groups are influenza A, B and C. The viruses can cause respiratory signs, and mammals can be affected. Recently a new influenza virus was found in the United States. The influenza virus was found in swine, but the natural host was later considered to be cattle. The virus was named influenza D. Different studies worldwide have confirmed the virus in a variety of regions. Antibodies have also been reported.     In this study, virologic and serologic methods were used to detect if influenza D circulates among cattle in Sweden. The serologic method performed was indirect ELISA. Serum and milk samples were investigated in the ELISA method. For the virologic detection a real-time RT-PCR was made, with a variety of study material.     Antibodies against influenza D were found in both serum and milk samples. No virus was found in the real-time RT-PCR. In Sweden the animal keeping is different compared to several other nations. For instance, the conditions of health and hygiene are better in Sweden, this may be an important cause of a system more resistant against spreading of infections. Influenza D could be more common in Sweden, but in that case further researches are needed to determine the prevalence.
367

Characterization of NeuN expression in the mouse neuronal NSC-34 cell line using RT-qPCR, immunological staining and siRNA-mediated gene suppression

Hallgren, Henrik January 2019 (has links)
Background: Acute spinal trauma is followed by a secondary injury that causes additional damage to the tissue. The mouse neuronal hybrid cell line NSC-34 is planned for studies regarding this process, wherefore the cell line needed to be established in the laboratory and a proof-of-concept study needed to be performed. A suitable target gene for this study was Neuronal Nucleus (NeuN), a neuronal marker expressed in nearly all neuronal cells although not yet studied in NSC-34. Aim: The aim of this project was to characterize the expression of NeuN in differentiated and undifferentiated NSC-34 cells and silence gene expression by using siRNA. Methods: RT-qPCR was used to measure NeuN expression during passages 5 to 15 and a comparison was performed between one early and one late passage. Lipofectamine® RNAiMAX was used for siRNA-treatment in different concentrations and several different medium compositions were tested as differentiation media. Results: NeuN was expressed in passages 5 to 15, with decreased expression levels in passage 13 (ΔCt 15.36 ± 0.16) compared to passage 5 (ΔCt 15.09 ± 0.16), p < 0.05. The expression levels did not change after differentiation. siRNA-treatment yielded knockdown when using  high concentrations of the reagent (p < 0.05). Conclusion: NeuN was expressed in a stable, low level throughout passages 5 to 15 with a slightly decreased expression during later passages and no change after differentiation. The siRNA-treatment suppressed gene expression, although further optimization is needed to increase the suppression.
368

Polyvinylalcohol-carbazate (PVAC) inhibits bacteria growth

Syk, Jakob January 2019 (has links)
Abstract Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used. Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used.
369

Projects, management, and protean times : engineering enterprise in the United States, 1870-1960 / Engineering enterprise in the United States, 1870-1960

Pinney, Benjamin W January 2001 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Program in Science, Technology and Society, 2001. / Includes bibliographical references (295-338). / In this dissertation, I trace methods for organizing skilled workers engaged in creative, limited-term projects in the United States between the nineteenth century and the 1950s. Examining eras of system building in technical fields-civil engineering in the nineteenth century, laboratory administration in the 1910s and 1920s, aircraft design in the 1930s, and electronics in the 1950s-I show that recent discourse on the management of innovation and change is a manifestation of a cyclically recurring conversation. This story complicates prevalent views of management theory and practice before World War II by recovering a thread obscured by emphasis on the organization of integrated, divisional companies and operative labor within them. Applying ideas from recent work in organization studies to distill common aspects of the management problems and labor processes individuals have confronted and theorized, I find common patterns: managers of construction firms, engineering departments, and research laboratories have again and again theorized the fast-moving, knowledge-intensive, relational organization, doing so long before these terms were available. Such thinking has been driven both by practical needs and because external pressures have forced explanation of seemingly uncontrolled, irrational work. Practically, the transferability of management techniques among settings such as construction and research has reflected kinships between labor and communication processes: each has involved skilled workers producing complex artifacts in uncertain physical, technical, and social environments. / (cont.) The need to explain such work, though, has been as much about external representation as internal control. From origins in government oversight of appropriations and military use of esprit de corps to cohere organizations under stress, tools used to manage project-based enterprises have been applied in response to the speed, scale, and complexity of the work itself. At the same time, engineers have explained the management of their work to deflect pressures to apply the logics of factory production and Taylorist scientific management to the organization of skilled labor. As explanations of the differences between building and operating and as delineations of points and terms of physical and cultural contact, representations of engineering work in schedules, budgets, organization charts, and narratives have both controlled and insulated work. / by Benjamin W. Pinney. / Ph.D.
370

Comparison of Focus and Audience Between Seneca’s Natural Questions and Pliny’s Natural History

Ely, Joshua 01 May 2014 (has links)
ABSTRACT Around 65 AD, the Ancient Roman philosopher Seneca wrote his only text concerning Natural Phenomenon: Natural Questions. Considered since medieval times as part of a trinity of great thinkers including Plato and Aristotle, Seneca’s work in rhetoric, philosophy, and legal theory still receive praise today. The praise is not replicated for Natural Questions, however. Modern historians who consider the work paint it as uninspiring. Pliny, another Roman author and philosopher, wrote a far more encompassing and detailed work called Natural History, and it is this work that is considered the premier Roman comment on Natural Philosophy. These contemporaneous works become juxtaposed and used to criticize Seneca’s work as inferior. A deeper consideration of the texts --primarily the subject material and use of poetry-- will determine that Seneca and Pliny wrote to different audiences and belong to different genres.

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