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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.
111

Literature Review on System Dynamics and Simulation

Linnéusson, Gary January 2006 (has links)
This report is a literature review of System Dynamics (SD) and simulation, with enough information so the receiver can form a mental model of his own of what SD is. It started in the 1950s by Jay W. Forrester at the Massachusetts Institute of Technology, a devoted man that through his career always sought for practical applications of theory and gained skills. The key in why this new way of approaching problems in complex systems was its strength in capturing the dynamics, through the use of a computer to run a modeled system for a set of time and experimenting on which variables to modify or rearrange. SD methodology uses the theory of information feedbacks (i.e. closed loop structures), and the structure is based on the decision making processes or policies that interrelate in ways in the system. The model is valid if it shows the same dynamic behavior as the real system. In the report you will find some history and background to SD and the contents of the methodology, some application areas and two models; of which simulation is performed, one made by Jay Forrester and one very simple made by Gary Linnéusson. Main purpose with this review was to find out if SD could serve as a tool for simulating organizational development. If it can, further research on how will be part of a doctoral study project within CAPE, an Industrial Graduate School in Advanced Production Engineering. This due to that Arkivator Falköping AB is interested in to conduct an attendee in that School which would research on: "developing a method that would support management in decisions to develop their organization". The result of this review shows that SD can be a tool to treat that issue, one of very few tools that consider interrelations and interactions within organizational systems.
112

Retractions, Post-Publication Peer Review and Fraud: Scientific Publishing's Wild West

Oransky, Ivan 27 October 2016 (has links)
Presentation given on October 27, 2016 at Data Reproducibility: Integrity and Transparency program as part of Open Access Week 2016. / Ivan Oransky and Adam Marcus founded Retraction Watch in 2010. Unbeknownst to them, retractions had grown ten-fold in the previous decade. Oransky will discuss the reasons for that increase, whether fraud is on the rise, the growth of post-publication peer review, and other trends he and Marcus have seen as they've built a site that is now viewed by 150,000 people per month, and funded by philanthropies including the MacArthur and Arnold Foundations.
113

Pólipos colorectales: actualización en el diagnóstico

Arévalo, F., Aragón, V., Alva, J., Perez Narrea, M., Cerrillo, G., Montes, P., Monge, Eduardo 11 August 2014 (has links)
El diagnóstico histológico de los pólipos colorrectales determina la conducta que tomará el médico especialista con el paciente. Con la aparición de nuevos pólipos en los últimos años, la clasificación histológica se ha tornado más compleja y amplia. Nuestro objetivo es actualizar los conceptos en el diagnóstico histológico de pólipos de colon de una manera clara y de fácil comprensión, especialmente para gastroenterólogos y patólogos.
114

Acute Endovascular Reperfusion Therapy in Ischemic Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Osanai, Toshiya, Pasupuleti, Vinay, Deshpande, Abhishek, Thota, Priyaleela, Roman, Yuani, Hernández, Adrian V., Uchino, Ken 06 May 2015 (has links)
uchinok@ccf.org / Background Randomized controlled trials (RCTs) of endovascular therapy for acute ischemic stroke have had inconsistent results. We evaluated the efficacy and safety of endovascular therapy in published RCTs. Methods We performed a systematic review of RCTs of endovascular therapy with thrombolytic or mechanical reperfusion compared with interventions without endovascular therapy. Primary outcome was the frequency of good functional outcome (modified Rankin scale (mRS) of 0-2 at 90 days) and secondary outcomes were mortality at 90 days and symptomatic intracranial hemorrhage (sICH). Random-effects meta-analysis was performed and the Cochrane risk of bias assessment was used to evaluate quality of evidence. Results Ten studies involving 1,612 subjects were included. Endovascular therapy was not significantly associated with good functional outcome (Relative Risk [RR] =1.17; 95% CI, 0.97 to 1.42; p=0.10 and Absolute Risk Difference [ARD] =7%; 95%CI -0.1% to 14%; p=0.05); heterogeneity was moderate among studies (I2=30%). Mortality was unchanged with endovascular therapy (RR=0.92; 95 % CI, 0.75 to 1.13; p=0.45) and there was no difference in sICH (RR=1.20; 95 % CI, 0.79 to 1.82; p=0.39). The quality of evidence was low for all outcomes and the recommendation is weak for the use of endovascular therapy as per GRADE methodology. Conclusions Intra-arterial therapy did not show significant increase in good outcomes and no changes in either mortality or sICH in patients with acute ischemic stroke. We need further RCTs with better design and quality to evaluate the true efficacy of endovascular therapy.
115

The Current State of Us Higher Education Social Media Policies with Regard to Teaching and Learning: a Document Review Needs Assessment

Reed, Adalheidur Steinunn 12 1900 (has links)
In the world we live in today, having a social media account such as Facebook, LinkedIn, Twitter, or Google+ has become deeply ingrained in our society. The old way of networking with who you knew or who knew your family is no longer in play for many people. In the times in which we live, much personal and professional networking is completed via social media. The old way of networking had unwritten rules of engagement which, basically, were to be respectful and not cause any embarrassment within the network. Rules for best practice engagement are still evolving for this new way of using social media for personal and professional networking, which is the premise for the current study which addresses: the gap in U.S. university social media policies, with regard to teaching and learning. In order to gauge the policy interlude, a sample of over 49 U.S. university social media policies were gathered for a comprehensive document analysis. The Google search engine was used to find the policies, next the qualitative software NVivo10 was used to procure and analyze the policies. Additionally, triangulation was performed by three member checking volunteer investigators. The results of the study, disclosed that current policies are intended to train faculty and staff, in the legal and proper manner, in which the universities expect their employees to positively represent the sampled universities.
116

Stochastic joint replenishment problems : periodic review policies

Alrasheedi, Adel Fahad January 2015 (has links)
Operations Managers of manufacturing systems, distribution systems, and supply chains address lot sizing and scheduling problems as part of their duties. These problems are concerned with decisions related to the size of orders and their schedule. In general, products share or compete for common resources and thus require coordination of their replenishment decisions whether replenishment involves manufacturing operations or not. This research is concerned with joint replenishment problems (JRPs) which are part of multi-item lot sizing and scheduling problems in manufacturing and distribution systems in single echelon/stage systems. The principal purpose of this research is to develop three new periodic review policies for stochastic joint replenishment problem. It also highlights the lack of research on joint replenishment problems with different demand classes (DSJRP). Therefore, periodic review policy is developed for this problem where the inventory system faces different demand classes that are deterministic demand and stochastic demand. Heuristic Algorithms have been developed to obtain (near) optimal parameters for the three policies as well as a heuristic algorithm has been developed for DSJRP. Numerical tests against literature benchmarks have been presented.
117

Efficacy of artemisinin derivatives in treating severe malaria in children: A systematic review and meta-analysis

Praygod, George 01 November 2006 (has links)
Student Number : 0416598H - MSc research report - School of Public Health - Faculty of Health Sciences / Background Evidence shows that the efficacy of intravenous quinine, which is the mainstay for treating severe malaria in children, is decreasing. Artemisinin derivatives are the potential replacement for quinine. Their efficacy compared to quinine in treating severe malaria in children is not well known. Objective To assess the efficacy of parenteral artemisinin derivatives versus parenteral quinine in treating severe malaria in children. Search strategy The Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2005), MEDLINE (1966 to October 2005), EMBASE (1980 to October 2005), and LILACS (1982 to October 2005) were searched. Malaria researchers and a pharmaceutical company were contacted. In addition, conference proceedings were also searched. Selection criteria Randomised controlled studies comparing parenteral artemisinin derivatives with parenteral quinine in treating severe malaria in children. All trials had to report mortality as an outcome. Data collection After data were extracted, two individuals independently assessed the trial quality. In addition, information on adverse effects from the studies was also collected. Main results Eleven trials were selected (1455 subjects), nine of them from Africa and the rest from Asia. Allocation concealment was adequate in seven trials (1238 subjects). Overall there was no difference in mortality between artemisinin derivatives and quinine (Risk Ratio= 0.89, 95% confidence interval 0.71 to 1.1). There was no difference in mortality between adequately concealed and inadequately concealed /unconcealed trials (Risk Ratio = 0.93, 95% confidence interval 0.74 to 1.16 and Risk Ratio=0.66, 95% confidence interval 0.36 to 1.22). In Parasite Clearance Time (PCT), though there was no statistical difference between the two groups there was a tendency towards favouring the artemisinin derivatives (weighted mean difference among studies which reported PCT as mean was -4.76 with 95% confidence interval -9.68 to 0.17 and all three studies which reported PCT as median showed that artemisinin derivatives cleared parasites faster than quinine, each had p<0.001). However; when only trials with adequate concealment were considered this potential advantage disappeared. In exploring heterogeneity for PCT, it was shown that study settings (Asia versus Africa) might have been a cause for heterogeneity. The artemisinin derivatives resolved coma faster than quinine (weighted mean difference=-5.32, 95%CI: -8.06 to -2.59), but when only trials with adequate concealment were considered this difference disappeared. Other secondary outcomes i.e. Fever clearance time, Incidence of neurological sequelae, and 28th day cure rate showed no significant difference between artemisinin derivatives and quinine. There was no enough data to make meaningful comparison of adverse effects between the two groups. Conclusions The available evidence suggests that parenteral artemisinin derivatives are as efficacious as quinine in preventing mortality from severe malaria in children.
118

An exploratory review of temperament research: Trends and implications for theory and intervention in the fields of developmental psychology and education

Farbach, Karline Rose 19 May 2008 (has links)
Temperament research has grown exponentially over the past decades. Diverse though the body of temperament research may be, due to the interest of many fields of study in this construct, fairly considerable areas of consensus in the understanding of temperament as a psychological construct has been achieved over the years. In other words, there is general agreement in the field that the notion that temperament is biological and genetic and that temperament plays a role in developmental contexts. A review of recent temperament research (from 1998 to 2005) was done for this study. An automated search of many databases was conducted, as well as a hand search of well-accredited journals, mostly from the disciplines of developmental psychology and education. Based on selected criteria, 102 studies were chosen for review. The findings of this study, based on an analysis of the selected studies, follow. For example, it was found that the large majority of the studies selected were methodologically sound. It was also noted that the various themes elicited from the analysis tended to follow the trends temperament research was following before 1998, at the beginning of this review. Evidence was also found that suggested there was a shift from using psychomedical frameworks towards constructivist, ecosystemic frameworks for underpinning temperament research, which suggests that contemporary temperament research is more likely to be studied from a developmental stance than it was a few years ago. The findings from this analysis were applied to issues in temperament research and practice in the context of developmental psychology and education.
119

O impacto do controle de constitucionalidade na evolução da democracia / The impact of judicial review in the democracy evolution

Oliveira, Emerson Ademir Borges de 25 October 2013 (has links)
O princípio democrático está inscrito nas Constituições contemporâneas como fundamental para o desenvolvimento do Estado Constitucional. Embora o conceito possa variar, é certo que existem alguns pressupostos e características que permitem avaliar o status democrático de uma sociedade, bem como a existência de efetividade aos direitos diretamente decorrentes da democracia, vale dizer, direitos voltados à instrumentação do princípio. O projeto constitucional se inscreve cotidianamente e passa a exigir o agir do Poder Público, em qualquer de suas funções, pois a efetivação da Constituição é dever de todos. Quando ausente a efetividade, passa-se a cogitar a transcrição dos direitos sobre a democracia pela veia constitucional. E ultrapassada a vertente meramente aplicadora da lei concepção liberal da separação de poderes -, o Judiciário erege como criador do Direito em um aspecto interpretacionista. Surge, então, a discussão acerca dos limites da interpretação e das técnicas de controle de constitucionalidade para efetivação da democracia. Isto é, a discussão acerca do liame que separa a interpretação criadora da criação interpretativa, assim como o modo técnico-racional utilizado pelo Judiciário para realizar o princípio democrático. De qualquer forma, torna-se imprescindível a análise circunstanciada do modo de interpretação, até mesmo para que nunca se perca de vista o dever de racionalidade que deve permear a decisão jurisdicional. O objetivo não é negar o evidente processo criativo do Judiciário, mas entender seu funcionamento, de modo que seu exercício não exceda a interpretação razoável dos preceitos constitucionais. / The democratic principle is present in the contemporary Constitutions as the central for the development of the constitutional State. Although the concept may vary, there are some assumptions and characteristics that allow the evaluation of a society´s democratic status, as well as the existence of effective directly democratic rights. In other words, rights capable of exercising the principle. The constitutional project is performed daily and it requires the action of government, in all of its functions, since the execution of the Constitution is an obligation of all. When the effectiveness is left beside, its common to cogitate the transcription of rights about democracy in the Constitution. And once the thought of the Judiciary only as a law enforcer liberal conception of the separation of powers is overcame, the Judiciary assumes a role of rights creator in an interpretationist aspect. That´s when the discussion about the limits of interpretation and judicial review techniques in the effectiviness of democracy comes to surface. In other words, the discussion that envolves the bond that separates creative interpretation from interpretative creation, as the technical-rational mode used by the Judiciary to accomplish the democractic principle. Either way, it becomes essential the detailed analysis of the form of interpretation adopted, as a way to never left aside the rationaily duty that should permeate judicial decision. The goal is not to deny the obvious creative process of Judiciary, but to understand its function so its exercise never exceeds the reasonable interpretation of fundamental precepts.
120

O impacto do controle de constitucionalidade na evolução da democracia / The impact of judicial review in the democracy evolution

Emerson Ademir Borges de Oliveira 25 October 2013 (has links)
O princípio democrático está inscrito nas Constituições contemporâneas como fundamental para o desenvolvimento do Estado Constitucional. Embora o conceito possa variar, é certo que existem alguns pressupostos e características que permitem avaliar o status democrático de uma sociedade, bem como a existência de efetividade aos direitos diretamente decorrentes da democracia, vale dizer, direitos voltados à instrumentação do princípio. O projeto constitucional se inscreve cotidianamente e passa a exigir o agir do Poder Público, em qualquer de suas funções, pois a efetivação da Constituição é dever de todos. Quando ausente a efetividade, passa-se a cogitar a transcrição dos direitos sobre a democracia pela veia constitucional. E ultrapassada a vertente meramente aplicadora da lei concepção liberal da separação de poderes -, o Judiciário erege como criador do Direito em um aspecto interpretacionista. Surge, então, a discussão acerca dos limites da interpretação e das técnicas de controle de constitucionalidade para efetivação da democracia. Isto é, a discussão acerca do liame que separa a interpretação criadora da criação interpretativa, assim como o modo técnico-racional utilizado pelo Judiciário para realizar o princípio democrático. De qualquer forma, torna-se imprescindível a análise circunstanciada do modo de interpretação, até mesmo para que nunca se perca de vista o dever de racionalidade que deve permear a decisão jurisdicional. O objetivo não é negar o evidente processo criativo do Judiciário, mas entender seu funcionamento, de modo que seu exercício não exceda a interpretação razoável dos preceitos constitucionais. / The democratic principle is present in the contemporary Constitutions as the central for the development of the constitutional State. Although the concept may vary, there are some assumptions and characteristics that allow the evaluation of a society´s democratic status, as well as the existence of effective directly democratic rights. In other words, rights capable of exercising the principle. The constitutional project is performed daily and it requires the action of government, in all of its functions, since the execution of the Constitution is an obligation of all. When the effectiveness is left beside, its common to cogitate the transcription of rights about democracy in the Constitution. And once the thought of the Judiciary only as a law enforcer liberal conception of the separation of powers is overcame, the Judiciary assumes a role of rights creator in an interpretationist aspect. That´s when the discussion about the limits of interpretation and judicial review techniques in the effectiviness of democracy comes to surface. In other words, the discussion that envolves the bond that separates creative interpretation from interpretative creation, as the technical-rational mode used by the Judiciary to accomplish the democractic principle. Either way, it becomes essential the detailed analysis of the form of interpretation adopted, as a way to never left aside the rationaily duty that should permeate judicial decision. The goal is not to deny the obvious creative process of Judiciary, but to understand its function so its exercise never exceeds the reasonable interpretation of fundamental precepts.

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