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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.
41

Hydrodynamic delivery for the study, treatment and prevention of acute kidney injury

Corridon, Peter R. 07 July 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Advancements in human genomics have simultaneously enhanced our basic understanding of the human body and ability to combat debilitating diseases. Historically, research has shown that there have been many hindrances to realizing this medicinal revolution. One hindrance, with particular regard to the kidney, has been our inability to effectively and routinely delivery genes to various loci, without inducing significant injury. However, we have recently developed a method using hydrodynamic fluid delivery that has shown substantial promise in addressing aforesaid issues. We optimized our approach and designed a method that utilizes retrograde renal vein injections to facilitate widespread and persistent plasmid and adenoviral based transgene expression in rat kidneys. Exogenous gene expression extended throughout the cortex and medulla, lasting over 1 month within comparable expression profiles, in various renal cell types without considerably impacting normal organ function. As a proof of its utility we by attempted to prevent ischemic acute kidney injury (AKI), which is a leading cause of morbidity and mortality across among global populations, by altering the mitochondrial proteome. Specifically, our hydrodynamic delivery process facilitated an upregulated expression of mitochondrial enzymes that have been suggested to provide mediation from renal ischemic injury. Remarkably, this protein upregulation significantly enhanced mitochondrial membrane potential activity, comparable to that observed from ischemic preconditioning, and provided protection against moderate ischemia-reperfusion injury, based on serum creatinine and histology analyses. Strikingly, we also determined that hydrodynamic delivery of isotonic fluid alone, given as long as 24 hours after AKI is induced, is similarly capable of blunting the extent of injury. Altogether, these results indicate the development of novel and exciting platform for the future study and management of renal injury.
42

Three-dimensional transient numerical study of hot-jet ignition of methane-hydrogen blends in a constant-volume combustor

Khan, Md Nazmuzzaman January 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Ignition by a jet of hot combustion product gas injected into a premixed combustible mixture from a separate pre-chamber is a complex phenomenon with jet penetration, vortex generation, flame and shock propagation and interaction. It has been considered a useful approach for lean, low-NOx combustion for automotive engines, pulsed detonation engines and wave rotor combustors. The hot-jet ignition constant-volume combustor (CVC) rig established at the Combustion and Propulsion Research Laboratory (CPRL) of the Purdue School of Engineering and Technology at Indiana University-Purdue University Indianapolis (IUPUI) is considered for numerical study. The CVC chamber contains stoichiometric methane-hydrogen blends, with pre-chamber being operated with slightly rich blends. Five operating and design parameters were investigated with respect to their eff ects on ignition timing. Di fderent pre-chamber pressure (2, 4 and 6 bar), CVC chamber fuel blends (Fuel-A: 30% methane + 70% hydrogen and Fuel-B: 50% methane + 50% hydrogen by volume), active radicals in pre-chamber combusted products (H, OH, O and NO), CVC chamber temperature (298 K and 514 K) and pre-chamber traverse speed (0.983 m/s, 4.917 m/s and 13.112 m/s) are considered which span a range of fluid-dynamic mixing and chemical time scales. Ignition delay of the fuel-air mixture in the CVC chamber is investigated using a detailed mechanism with 21 species and 84 elementary reactions (DRM19). To speed up the kinetic process adaptive mesh refi nement (AMR) based on velocity and temperature and multi-zone reaction technique is used. With 3D numerical simulations, the present work explains the e ffects of pre-chamber pressure, CVC chamber initial temperature and jet traverse speed on ignition for a speci fic set of fuels. An innovative post processing technique is developed to predict and understand the characteristics of ignition in 3D space and time. With the increase of pre-chamber pressure, ignition delay decreases for Fuel-A which is the relatively more reactive fuel blend. For Fuel-B which is relatively less reactive fuel blend, ignition occurs only for 2 bar pre-chamber pressure for centered stationary jet. Inclusion of active radicals in pre-chamber combusted product decreases the ignition delay when compared with only the stable species in pre-chamber combusted product. The eff ects of shock-flame interaction on heat release rate is observed by studying flame surface area and vorticity changes. In general, shock-flame interaction increases heat release rate by increasing mixing (increase the amount of deposited vorticity on flame surface) and flame stretching. The heat release rate is found to be maximum just after fast-slow interaction. For Fuel-A, increasing jet traverse speed decreases the ignition delay for relatively higher pre-chamber pressures (6 and 4 bar). Only 6 bar pre-chamber pressure is considered for Fuel-B with three di fferent pre-chamber traverse speeds. Fuel-B fails to ignite within the simulation time for all the traverse speeds. Higher initial CVC temperature (514 K) decreases the ignition delay for both fuels when compared with relatively lower initial CVC temperature (300 K). For initial temperature of 514 K, the ignition of Fuel-B is successful for all the pre-chamber pressures with lowest ignition delay observed for the intermediate 4 bar pre-chamber pressure. Fuel-A has the lowest ignition delay for 6 bar pre-chamber pressure. A speci fic range of pre-chamber combusted products mass fraction, CVC chamber fuel mass fraction and temperature are found at ignition point for Fuel-A which were liable for ignition initiation. The behavior of less reactive Fuel-B appears to me more complex at room temperature initial condition. No simple conclusions could be made about the range of pre-chamber and CVC chamber mass fractions at ignition point.
43

Development and preliminary validation of the romantic relationship functioning scale

Bonfils, Kelsey A. January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Background: Research has repeatedly shown that individuals with severe mental illness desire interpersonal and romantic relationships and that social support (including spousal relationships) is beneficial. In addition, social deficits in mental disorders can often get in the way of developing fulfilling relationships. However, there is little currently available to help clinicians and researchers assess romantic relationship functioning in those with mental illness. The aim of this pilot study was to examine reliability and validity of a new measure of functioning in romantic relationships, the Romantic Relationship Functioning Scale (RRFS). Method: The RRFS was constructed based on theory proposed by Redmond, Larkin, and Harrop (2010). In an analog study, we tested the measure in a sample of college students (N=387), examining reliability, stability over time, factor structure, and relationships with measures of psychopathology and related measures of social functioning to assess convergent validity. Results: The RRFS exhibited a hierarchical four-factor structure, supporting the use of a total score. Although subscales were supported in the factor analysis, other psychometric evidence was weaker, and the use of a total score is advocated. Internal consistency and test-retest reliability were acceptable for the total scale (>.8). The RRFS had moderate to large correlations in the expected direction with all psychopathology measures. In predictive models, overall mental health, social functioning, and fewer interpersonal difficulties predicted higher romantic relationship functioning. Conclusions: The RRFS total score shows preliminary evidence of reliability and validity. The RRFS has potential to be of use in treatment centers for undergraduates and for individuals with diagnosed mental disorders. Future research should further investigate the RRFS subscales and the measure’s performance in clinical samples.
44

Lineage tracing of Ascl1-expressing cells in the maternal liver during pregnancy

Nambiar, Shashank Manohar January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / To cope with the high metabolic demands of the body during pregnancy, the maternal liver adapts by increasing its mass and size. This increase is proportional to the increase in total body weight during the course of gestation. The pregnancy-induced maternal liver growth is a result of both hepatocyte hypertrophy and hyperplasia. Microarray analysis of pregnant maternal livers shows markedly different gene expression profiles when compared to a non-pregnant state. Most interesting was the 2,500-fold up-regulation in the mRNA expression of Ascl1, a transcription factor responsible for the differentiation of neural progenitor cells into various neuronal types, during the second half of pregnancy. Our investigation aimed at (1) characterizing the identity of maternal hepatic Ascl1-expressing cells and (2) tracing the fate of Ascl1-expressing cells in the maternal liver during pregnancy. Timed pregnancies were generated and non-pregnant (NP) and pregnant maternal livers were harvested and analysed. To identify the maternal hepatic Ascl1-expressing cells we used the Ascl1GFP/+ reporter mouse line. NP and gestation day 15 (D15) maternal livers were immunostained for green fluorescent protein (GFP). The result shows that GFP-positive, Ascl1-expressing cells are hepatocyte-like cells, which are present in D15 maternal livers, but absent in NP livers. The Rosa26floxstopLacZ/ floxstopLacZ;Ascl1CreERT2/+ mouse line was used to trace the fate of Ascl1-expressing cells during pregnancy. LacZ staining of gestation day 13 (D13) and 18 (D18) maternal livers demonstrates that D13 hepatic Ascl1-expressing cells (labeled with LacZ) undergo hyperplasia to repopulate a large portion of D18 maternal livers. Furthermore, LacZ and HNF4α co-staining of D13 and D18 maternal livers shows the presence of two populations of LacZ-expressing cells: HNF4α+ population and HNF4α- population. HNF4α+ LacZ-expressing cells represent hepatocyte lineage cells that are derived from Ascl1-expressing cells. We observe that, towards the end of pregnancy, a considerable portion of the maternal liver is comprised of hepatocytes derived from Ascl1-expressing cells. Taken together, our preliminary study suggests that pregnancy induces maternal liver turnover via Ascl1-expressing cells.
45

Die bepaling van standaarde vir die eenheidsbestuurder in geselekteerde hospitale

Van Dyk, Anneline Lynette 12 1900 (has links)
Thesis (MCur)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The traditional management practice of the unit manager has changed dramatically in the past decade. She is responsible to supply nursing services in an environment which is characterized by smaller operational budgets, rapid developments and changes in every sphere. The researcher has identified deficiencies in the management process of the unit manager. This led to the evaluation of the management activities of the unit manager in a selected group of hospitals. A quantitative, non-experimental, descriptive approach was followed with a questionnaire survey as research design. Standards were set and the management activities were evaluated against these standards. The main findings were: • The unit manager was not 100% involved in her comprehensive management task • The unit manager did not have the necessary training to empower her to manage effectively. The researcher recommends that the unit manager should be empowered by inservice education programmes but should also follow the formal management programmes at a recognized tertiary education institution. Keywords: Unit management / Standard formulation / AFRIKAANSE OPSOMMING: Die tradisionele bestuurspraktyk van die eenheidsbestuurder het oor die afgelope dekade dramaties verander. Sy is verantwoordelik vir die verskaffing van verpleegdienste in 'n omgewing wat gekenmerk word deur kleiner operasionele begrotings, vinnige vooruitgang en veranderinge op alle gebiede, Die navorser het leemtes in die bestuursproses van die eenheidsbestuurder geïdentifiseer. Dit het gelei tot die evaluering van die bestuursaktiwiteite van die eenheidsbestuurder in 'n geselekteerde groep hospitale. 'n Kwantitatiewe, nie-eksperimentele beskrywende navorsingsbenadering is gebruik met 'n vraelysopname as navorsingsontwerp. Standaarde is gestel waarteen die bestuursaktiwiteite geëvalueer is. Die belangrikste bevindinge was dat: • Die eenheidsbestuurder nie 100% betrokke was by haar omvangryke bestuurstaak nie • Die eenheidsbestuurder nie oor die nodige opleiding beskik wat haar bemagtig om hierdie bestuurstaak effektief te verrig nie. Die navorser beveel aan dat die eenheidsbestuurder bemagtig moet word deur middel van indiensopleidingsprogramme maar ook deur formele bestuursopleiding aan 'n erkende tersiêre opvoedkundige intansie moet te volg. Sleutelwoorde: Eenheidsbestuur/standaard formulering
46

A framework for the evaluation of research in South African Higher Education Institutions : conceptual and methodological issues

Masipa, Mochaki Deborah 03 1900 (has links)
Thesis (PhD (Social Science Research Methodology))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: This study aimed at establishing whether or not an integrated and appropriate system exists for the evaluation of research in the South African higher education system. As background to the assessment of research in South African higher education, models of research evaluation from other countries were reviewed and served as reference to the discussions on the local efforts. In each case the higher education research systems were reviewed, including existing efforts of research evaluation that exits alongside the systems. The review followed a pattern that focuses on areas including the history and rationale, purpose (s) for research evaluation, political/transformation contributions and methodological issues for a clearer understanding of the contributions made by the efforts. The study followed a multiple-case study approach to review the models and the South African situation, with the local research evaluation efforts embedded within the study of South Africa as a case. Five themes guided the reviews that were apparent for the final discussions of the study: the rationale and purpose of research evaluation, units of analysis used in the evaluation, dimensions/criteria used in research evaluation, governance and management of research evaluation processes and methodological issues related to research evaluation. The study revealed that none of the fragmented South African research evaluation efforts is suitable to deal with the transformation requirements expected of higher education institutions. This is mainly because of the voluntary nature of the current initiatives and their focus on the lowest level of units of analysis – the individual researcher. The one effort that would be better suited to meet the transformation imperatives – the HEQC institutional audits - does not concentrate on research exclusively but collectively addresses all core activities in institutions, reducing the attention necessary for research evaluation to make a meaningful contribution to higher education research. The study suggested a comprehensive design for the framework of South African research evaluation. The purpose identified for the envisaged exercise is the development and improvement of quality research of international standards across the system of higher education in order for research to make meaningful contributions to national demands. Programmes/departments in the higher education institutions are suggested as the units of analysis in which quality, productivity, relevance and viability serve as criteria for evaluation. / AFRIKAANSE OPSOMMING: Hierdie studie poog om vas te stel of 'n geïntegreerde en toepaslike stelsel bestaan vir die evaluering van navorsing in die Suid-Afrikaanse hoër onderwys stelsel. As agtergrond tot die beoordeling van navorsing in Suid-Afrikaanse hoër onderwys, word ‘n oorsig verskaf van die modelle van navorsing evaluering van ander lande. Dit het gedien as verwysing vir die besprekings oor die plaaslike pogings. In elke geval is ‘n oorsig gebied van die hoër onderwys navorsingstelsels , insluitend die bestaande pogings tot navorsing evaluering. Die oorsigte fokus op gebiede soos die geskiedenis en die rasionaal, doel van navorsing evaluering, politiese / transformasie bydraes en metodologiese vraagstukke vir' n beter begrip van die bydraes wat gemaak word deur die pogings. Die studie volg 'n meervoudige gevallestudie benadering tot die modelle en die Suid-Afrikaanse situasie, met die plaaslike navorsing evaluering pogings onderliggend in die Suid-Afrikaanse gevallestudie. Die oorsigte word gelei deur vyf temas: die rasionaal en doel van die navorsing evaluering, eenhede van analise wat gebruik word in die evaluering, dimensies / kriteria wat gebruik word in navorsing evaluering, beheer en bestuur van navorsing, en metodologiese evalueringsprosesse kwessies met betrekking tot navorsing evaluering. Hierdie temas is duidelik in die finale bespreking van die studie. Die studie het aangetoon dat nie een van die gefragmenteerde Suid-Afrikaanse navorsing evaluering pogings geskik is om die transformasie verwagtinge van hoër onderwys instellings te hanteer nie. Dit is hoofsaaklik as gevolg van die vrywillige aard van die huidige inisiatiewe en hul fokus op die laagste vlak van die eenhede van analise - die individuele navorser. Die een poging wat beter geskik sou wees die transformasiedoelwitte te ontmoet - die HEQC institusionele oudits - konsentreer nie uitsluitlik op navorsing nie, maar spreek gesamentlik alle kern aktiwiteite in instellings aan. Dit verminder die aandag wat nodig is vir navorsing evaluering om 'n betekenisvolle bydrae te lewer tot hoër onderwys navorsing . Die studie stel 'n omvattende ontwerp voor vir die raamwerk van Suid-Afrikaanse navorsing evaluering. Die doel wat vir die beoogde oefening geïdentifiseer word, is die ontwikkeling en verbetering van die kwaliteit navorsing van internasionale standaarde oor die stelsel van hoër onderwys sodat die navorsing betekenisvolle bydraes kan lewer tot die nasionale vereistes. Programme / departemente in die hoër onderwys instellings word voorgestel as die eenhede van analise waarin gehalte, produktiwiteit, relevansie en lewensvatbaarheid dien as kriteria vir evaluering.
47

Objectivity, power and interests : a sociological analysis

Jacobz, Melville 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Discourse about the human world has, since Socrates, been structured around the assumption that one view of a given matter is better than competing views, and that argumentation, if carried out correctly and systematically, will favour the view which has the preponderance of reasons and evidence on its side. If this supposition were dropped, the nature of social scientific inquiry would change significantly. For many commentators in the social sciences the ineliminable interpretative dimension of social inquiry and the standpoint-bound character of interpretation lead to the conclusion that we have to abandon any notion of objective truth in the social sciences. The central question raised in this thesis is whether this abandonment is inevitable or even plausible. Is it plausible to conflate objectivity and truth? Is objectivity a possible characteristic of the individual researcher or a characteristic of the scientific research process? Does the cultural environment of the researcher impact on the validity of research findings? If science is a social phenomenon, are scientific beliefs different from other beliefs? How do the interests of the individual researcher or the formal organisation of scientific practice impact on the validity of findings? What role does power play in the shaping of knowledge? These are the questions that will be addressed in the following thesis. The methodology of Max Weber serves as a point of departure and divergences and similarities to the work of Weber are explored in the writings of Kuhn, the Edinburgh School, Latour, Foucault, Habermas, as well as contemporary postmodernist and feminist writers. The analysis of these various concepts and approaches is not presented chronologically, but rather as an exposition of the contributors of various commentators in the fields of both the sociology of science and knowledge, and the philosophy of science. / AFRIKAANSE OPSOMMING: Diskoers oor die menslike wêreld is, sedert Socrates, gestuktureer rondom die aanname dat een siening van 'n gegewe saak beter is as mededingende sienings, en dat argumentasie, indien korrek en sistematies uitgevoer, ten voordeel sal wees van die siening wat gesteun word deur die oormaat van redes en bewyse. As ons hierdie aanname sou laat vaar, sal die stand van sosiaal wetenskaplike ondersoek ingrypend verander. Vir menige kommentator in die sosiale wetenskappe lei die onafwendbare interpretatiewe dimensie van maatskaplike ondersoek, en die standpunt-gebonde aard van interpretasie, tot die gevolgtrekking dat ons enige opvatting van objektiwiteit in die sosiale wetenskappe moet laat vaar. Die kernvraag in hierdie tesis is of hierdie verskuiwing onvermydelik of selfs aanneemlik is. Is dit geldig om objektiwiteit en waarheid saam te snoer? Is objektiwiteit 'n moontlike eienskap van die individuele navorser, of 'n eienskap van die navorsingsproses? Watter impak het die kulturele omgewing van die navorser op die geldigheid van die navorsingsbevindinge? As wetenskap 'n sosiale fenomeen is, is wetenskaplike oortuigings enigsins anders as ander oortuigings? Watter impak het die belange van 'n individuele navorser, of die formele organsiasie van wetenskaplike praktyk, op die geldigheid van bevindings? Watter rol speel mag in die vorming en skepping van kennis? Hierdie is die vrae wat aangespreek word in dié tesis. Die metodologie van Max Weber dien as vertrekpunt, en ooreenkomste tot en afwykings van die sienings van Weber word ondersoek in die werk van Kuhn, die "Edinburgh School", Latour, Foucault, Habermas, sowel as kontemporêre postmoderne en feministiese skrywers. Die analise van hierdie verskeie konsepte en benaderings word nie kronologies aangebied nie, maar eerder as 'n uiteensetting van die bydraes van verskeie kommentators op die gebied van die sosiologie van die wetenskap en van kennis, sowel as die filosofie van wetenskap.
48

Los estudios de síntesis como base para las evaluaciones económicas: necesidad de la valoración de su calidad.

Bolaños Díaz, Rafael, Mezones Holguín, Edward, Gutiérrez Aguado, Alfonso, Málaga, Germán 21 March 2014 (has links)
RB redactó el primer borrador del artículo y realizó la revisión final. EM redactó la versión presentada al comité editorial, elaboró las figuras del artículo, levantó las observaciones del comité editorial y redactó la versión final del artículo. AG realizó contribuciones al texto inicial, desarrolló la primera versión del resumen y revisó la versión final. GM realizó contribuciones al texto inicial, levantó las observaciones del comité editorial, realizó contribuciones al texto final y revisó la versión final. / Los estudios de síntesis (EDS): revisiones sistemáticas y metanálisis, son base para llevar a cabo las evaluaciones económicas en salud (EES). Los EDS, al permitir obtener parámetros para las probabilidades de estimación y de efectividad a partir de la combinación de resultados de estudios primarios y, al incluir en su metodología procesos de selección, evaluación, sistematización y síntesis, son considerados como el primer nivel de jerarquía en la evidencia científica. No obstante, pueden estar sometidos a sesgos y fallas metodológicas que afectan su validez. El presente artículo expone, inicialmente, la importancia de la aleatorización en la jerarquización de los diseños de investigación; luego se revisa los principales factores que afectan la validez de los EDS, incidiendo en el sesgo de publicación, la heterogeneidad y la inclusión de estudios primarios con objetivos principales distintos al del EDS; asimismo, se presenta a los estudios individuales como una alternativa válida para el desarrollo de una EES. Se concluye que uno de los aspectos claves en una EES es la selección adecuada de los tipos de estudio, sean estos primarios o secundarios. / Synthesis studies (SS): systematic review and meta-analysis are the basis for developing Health Economic Evaluations (HEE). SS allow us to obtain parameters for estimating probabilities and effectiveness from the combination of the results of primary studies, and, as they include in their methodology the selection, evaluation, systematization and synthesis processes, they are considered the first level of hierarchy in scientific evidence. Nevertheless, they can be prone to bias and methodological failures that can affect the validity of their results. This article initially presents the relevance of the randomization in the hierarchic classification of research designs, then it reviews the main factors affecting the validity of the SS, emphasising the publication bias, the heterogeneity and the inclusion of primary studies with main objective differing from the one of the SS. Moreover, it presents individual studies like a valid alternative for the development of a SS. The conclusion is that one of the key aspects in a SS is the correct evaluation of the study types and the objective evaluation of their quality, being these primary or secondary.
49

Integration of Risk and Multiple Objectives inPriority Setting for Agricultural Research

Gierend, Albert 01 January 1999 (has links)
Prioritätensetzung in der Agrarforschung ist ein komplexes Entscheidungsproblem angesichts der Unsicherheit in der Abschätzung der erwarteten Wirkungen von Forschung und Technologien und den vielfältigen sozialen und wirtschaftlichen Zielen, die mit der Generierung von Wissen und neuen Technologien in landwirtschaftlichen Forschungsinstitutionen in Entwicklungsländern verbunden sind. Diese Arbeit versucht durch die Anwendung von formalen und quantitativen Evaluierungs- und Entscheidungsmethoden mit der besonderen Berücksichtigung von Unsicherheit und multiplen Zielen einen Beitrag zur Methodenverbesserung in der Prioritätensetzung zu leisten. Zur Darstellung dieser Methoden wurde als Fallstudie das nationale Milchviehforschungsprogramm des "Kenyan Agricultural Research Institute" (KARI) ausgewählt. Gegenstand der Analyse sind 19 geplante Forschungsprojekte, die anhand eines stochastischen Evaluierungsansatzes ("Economic Surplus" und Monte Carlo Simulation) hinsichtlich ihrer ökonomischen Wirkungen auf den kenianischen Milchmarkt untersucht wurden. Die Evaluierungsergebnisse der Forschungsprojekte und anschließende Bewertung anhand verschiedener stochastischer Dominanztests zeigen, daß die Ableitung einer klaren Präferenzstruktur und Rangordnung innerhalb der Projekte nach ökonomischen Kriterien, z.B. Gegenwartswert und Kosten-Nutzenrelation, in vielen Fällen nicht möglich ist, sondern vielmehr von den unterstellten Risikopräferenzen abhängt. Dies bedeutet, daß aus der Sicht eines Planers eine differenzierte und vorsichtige Interpretation und Beratung des Forschungsmanagements vorzunehmen ist. Dies steht im Gegensatz zu einer deterministischen Investitionsanalyse. Mehrere mathematische Programmierungsmodelle wurden zur Analyse von multiplen Zielen, der Untersuchung der Wirkungen von Verteilungsaspekten und unterschiedlicher Risikopräferenzen auf die Zusammensetzung eines optimalen Forschungsportfolios entwickelt und angewandt. Obwohl in den meisten Fällen eine Änderung der Risikoeinstellung auch eine Änderung des optimalen Portfolios bewirken würde, sind die ökonomischen Unterschiede gemessen am Gegenwartswert der alternativen Portfolios unbedeutend. Die Analyse der Zielkonflikte zwischen Effizienz- und Verteilungsziel wurde unter zwei unterschiedlichen Blickwinkeln für das Verteilungsziel untersucht: zum einen als räumliche und regionale Allokation des Forschungsnutzens, und zum anderen zwischen kenianischen Konsumenten und Produzenten von Milch. Aus den Modellergebnissen wird deutlich, daß eine spezielle Förderung von Produzenten- sowie Konsumenteninteressen nur beschränkt möglich ist, d.h. die jeweiligen Planungsoptionen nur geringe Umverteilungswirkungen erzielen. Ganz anders stellt sich die Situation bei einer regionalen Differenzierung dar. Dort würden je nach relativer Bedeutung einzelner Regionen starke Umverteilungswirkungen in den regionalen Einkommen auftreten. Allerdings sind diese Optionen im Vergleich zu einer "neutralen", d.h. regional indifferenten Ausrichtung mit großen Effizienzverlusten verbunden. / Priority setting in agricultural research is a complex decision making problem due to the inherent uncertainty surrounding the impact of research activities and the multiple social and economic research objectives under which research institutions in developing countries have to operate. This study attempts to apply formal and quantitative evaluation and decision making methods for a more rigorous and explicit analysis of the uncertainty and multiple research objectives. These methods are illustrated by applying them to a priority setting exercise for the National Dairy Research Program of the Kenyan Agricultural Research Institute (KARI) conducted in 1996. A set of 19 planned dairy research projects was proposed and specified by KARI scientists and the economic impact assessed based on a stochastic evaluation framework using economic surplus methods and Monte Carlo simulation. Results show that comparing these projects by stochastic dominance criteria with respect to the expected net present value and cost-benefit ratio the final rank order is very much subject to assumed risk preferences of the decision- makers. Thus, decision advice on the type of prioritised projects for implementation and fund raising is much less clear-cut than a deterministic evaluation would suggest. Mathematical programming techniques were applied to analyse the trade-off between multiple research objectives, to examine the distributional consequences of research, and to explore how different risk strategies (from risk aversion to risk proneness) would affect the selection of a optimal research portfolio from the planned dairy research projects. Although risk has a strong bearing on the composition of a research portfolio for various different funding levels the economic implications are not significant in terms of net present value. In a Multiple-objective programming framework the trade-off between efficiency and equity was examined. Equity concern was looked at two different angles: first, by a spatial distribution of the research benefits, and second by the distributions among consumer and producer groups. Results show a limited scope of directing the dairy research plan either for the sake of consumers or producers while the scope of targeting different production zones in Kenya is much larger although the trade-offs in terms of foregone welfare between different zones are very pronounced.
50

Avaliação metodológica dos artigos publicados na área de ortopedia e traumatologia nos anos de 2004 e 2005 / Evaluation of articles published within the field of Orthopedics and Traumatology in the years 2004 and 2005

Amatuzzi, Maria Luiza Lotumulo 19 June 2007 (has links)
A autora avaliou a qualidade dos artigos publicados na literatura brasileira, na área de Ortopedia e Traumatologia. Foi feita a revisão de todos os artigos constantes dos sumários da Acta Ortopédica Brasileira e da Revista Brasileira de Ortopedia, em seus fascículos publicados nos anos de 2004 e 2005. Considerou que o conteúdo dessas duas Revistas retrata a produção científica nacional na área e que sua análise pode responder ao objetivo do trabalho. Após o levantamento da literatura, foi escolhida a classificação de Cook adaptada por Atallah para a classificação dos artigos por Nível de Evidência. Foi utilizada a lista de Atallah para a avaliação metodológica para trabalhos sobre terapêutica, etiologia e diagnóstico. Os artigos de ciência básica foram avaliados por suas características metodológicas e classificados por parâmetros representativos de seu nível e utilizados formulários preenchidos por dois avaliadores. Foram aplicados cálculos de estatística descritiva. A autora conclui que a qualidade metodológica dos artigos publicados nas revistas analisadas é inadequada e tem baixo Nível de Evidência. / The author evaluated the quality of articles published within the field of Orthopedics and Traumatology in Brazil. A review was conducted on all the articles appearing in the summaries of Acta Ortopédica Brasileira and Revista Brasileira de Ortopedia, in their issues published in the years 2004 and 2005. The author took the content of these two journals to portray the national scientific production in this field and made the assumption that analysis of these journals would provide answers for the study objective. After surveying the literature, the classification of Cook as adapted by Atallah for classifying articles by evidence level, was chosen. Atallahs list for evaluating the methodology of studies on therapies, etiologies and diagnoses was utilized. Articles on basic science were evaluated according to the methodological characteristics and were classified using parameters that represented their level. Forms filled out by two evaluators were utilized. Descriptive statistical calculations were applied. The author concluded that the methodological quality of the articles published in the journals analyzed is inadequate and provides a low level of evidence.

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