• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 133
  • 45
  • 32
  • 27
  • 13
  • 8
  • 8
  • 8
  • 4
  • 4
  • 4
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 335
  • 335
  • 180
  • 173
  • 30
  • 29
  • 28
  • 28
  • 27
  • 26
  • 26
  • 25
  • 24
  • 24
  • 21
  • 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

The Complexity of Peacebuilding : A case study of Somalia from 1991-1995

Mohamed, Abduljabar Abdulkadir Sheikh January 2021 (has links)
This paper presents the complexity of peacebuilding by looking at different types of peacebuilding models. To understand the peacebuilding models, this paper reviews different scholarly pieces of literature on the topic of peacebuilding. Furthermore, the paper focuses on the case of Somalia to determine the suitable peacebuilding model for Somalia. Somalia has faced one of the longest civil wars in Africa after the collapse of the government. To propose suitable peacebuilding for Somalia, the paper reviews different types of peacebuilding attempts that were conducted in Somalia by both international organizations and local peacemakers. These processes include an UN-led top-down approach and a bottom-up approach initiated by elders and local respected individuals. From reviewing different types of peacebuilding literature, the finding reveals conflict resolution specifically Ramsbotham et al (2011) as the best suitable peacebuilding model for Somalia.
112

Information strategies : A Qualitative study in the retail sector

Svensson, Niklas, Gasnier, Olivia January 2021 (has links)
Purpose The goal of this research is to define top-down and bottom-up approaches as well as the communication processes and the information flow to see how it is used and matched with day-to-day activities in several retail stores. To meet this goal, the following research questions have been formulated: ● How do organizations use information strategies such as top-down and bottom-up management? ● What are the means to be used in information strategies so that the envisaged objectives can be achieved?  Method To meet that objective, a study has been performed on seven store managers from seven different retail shops through interviews from which the empirical data has been gathered. The latter has been combined with a theoretical framework to achieve the purpose. Findings Based on the empirical results taken from the seven store managers, the authors were able to see and understand how each of them was using information strategies and what were the challenges and improvements related to it. Limitations The authors chose to limit their research to the retail industry in Sweden, therefore the outcome of this study cannot be applied to other industries or countries. Moreover, the interviews have been only given to store managers, which implies that the employees’ perspective on the subject is not analyzed here.
113

Analyzing the benefits of reading strategy instruction for reading comprehension in L2 English learners / En analys av de positiva effekterna av lässtrategiundervisning på läsförståelse hos L2 Engelskaelever

Wibell-Kähr, Gustav, Nilsson Ek, Filip January 2021 (has links)
This study investigates the potential benefits of reading strategy instruction in the English classroom in an L2 learner context. We examined the effects of reading strategy instruction on reading comprehension for L2 learners and investigated howreading strategies should be taught in the context of Swedish upper secondary school. To this end, six empirical studies were evaluated. We found that reading strategy instruction had a positive impact on reading comprehension in general, but that it was especially effective for certain student groups. Namely, intermediate learners benefitted more than other groups, while the weakest students improved the least in response to instruction. Furthermore, the research we examined suggests that it may be advantageous to focus on teaching a single strategy at a time. However, it is important to eventually expand students’ range ofstrategies long-term, since many pupils tend to over-rely on problem-solving strategies to the detriment of their progress in reading. Thus, emphasizing the less frequently used support strategies during instruction may help students read moreefficiently. Additionally, for reading strategies to best benefit learners, they should be taught in a clear, step-by-step manner. Finally, we argue that using aspects of Vygotsky’s sociocultural theory to inform lesson plans would greatly benefit students, especially those who are less proficient. Due to the lack of research in the increasingly heterogeneous Western world, future research should investigate how reading strategy instruction behaves in a multicultural context in the West.
114

Mass spectrometry approaches for profiling protein-protein interactions

Xu, Xiaobin 22 January 2016 (has links)
This dissertation is focused on developing cross-linking and mass spectrometry methodologies to study protein-protein interactions. Top-down cross-linking, in combination with mass spectrometry, provides advantages over bottom-up approaches, such as retaining posttranslational modification. Intermolecular cross-linking studies focus on defining protein complex topology and protein-protein interactions. We first developed the top-down MS approach to analyze intermolecular cross-linking in human hemoglobin. Both α-α and β-β intermolecular cross-linking were found and the cross-linking sites on the protein were identified, obtaining distance constraints between subunits of the human hemoglobin protein complex. This methodology would be a promising approach to characterize protein complexes and protein-protein interactions with high throughput and automation. This dissertation also focuses on development of cross-linking mass spectrometry to study synphilin-1 interactors and aggresome formation. Synphilin-1 is a protein that promotes the formation of protein aggregates and aggresome formation upon proteasome inhibition, and is implicated in Parkinson disease. Synphilin-1 contains several protein binding motifs. The biological functions of synphilin-1 and its role in aggresome formation and the pathogenesis of Parkinson disease remain to be elucidated. We utilized tandem affinity purification and label-free mass spectrometry to explore the patterns of cellular proteins associated with synphilin-1. We identified 57 synphilin-1 interacting proteins, and functional enrichment and pathway analysis showed that many of the associated proteins are involved in chromatin modulation, RNA and protein metabolism. Furthermore, we developed a proteomic strategy to identify synphilin-1 binary interacting partners as well as interacting domains using affinity purification followed by isotopically tagged cross-linking in combination with mass spectrometry. We found 24 newly discovered proteins that directly bind to synphilin-1. The proteins were mainly involved in RNA metabolism. The coiled-coil domain (CC), ankyrin-like repeat domain 2 (ANK2), and the protein aggregate promoting domain, appeared to the main regions that bound proteins. The functions of synphilin-1 interacting proteins, such as CK2, in aggresome formation were studied. The results show that CK2 is an important regulator of aggresome formation, but not through its kinase activities. Involvement of synphilin-1 in autophagy was also investigated. Knockdown of synphilin-1 shows that synphilin-1 impacts autophagy.
115

Hur läromedel i svenskämnet presenterar läs- och skrivinlärning : En kvalitativ textanalys med fokus på interaktionsgrad samt läromedlens förhållningssätt till introduktion av språkinlärning

Borg, Tove, Ewertson, Izabella January 2020 (has links)
Syftet med denna studie är att bidra med utökad kunskap om vilka förhållningssätt olika läromedel har gällande introduktionen av läs- och skrivinlärning samt i vilken grad läromedlen möjliggör interaktion mellan undervisningens samtliga deltagare. Studien är baserad på en kvalitativ textanalys där fyra läromedel, Simalabim grundbok 1, Prima svenska 1, Forma språket ettan samt Den magiska kulan, har analyserats utifrån sex olika kategorier, som alla berör det sociokulturella perspektivet. De sex kategorierna är: top-down, bottom-up, enskilt arbete, arbete i par, arbete i helklass samt högläsning av lärare. Kategorierna är baserade på det sociokulturella perspektivet, en socialkonstruktivistisk syn på kunskap samt den proximala utvecklingszonen. Analysen grundas i forskningsfrågorna:   Vilka förhållningssätt har de studerade läromedlen gällande introduktion av läs- och skrivinlärning? I vilken grad möjliggör läromedlen interaktion mellan undervisningens samtliga deltagare?   Resultatet redogörs med hjälp av en tabell (se tabell 2), som senare står till grund för en jämförelse. Jämförelsen tar avstamp i Lev Vygotskijs tankar inom det sociokulturella perspektivet där det lyfts fram att samspelet mellan människor är grunden till utveckling och lärande. Jämförelsen relateras även till den tidigare forskning som studien presenterar.   Studiens resultat påvisar olikheter i läromedlen gällande användningen av arbetssätt som möjliggör mellanmänsklig interaktion och samspel. Det visas att det vanligaste är att olika arbetssätt kombineras, undantaget en arbetsbok där endast ett tillvägagångssätt, enskilt arbete, används. Även Olga Dysthes tankar kring att olika arbetssätt bör kombineras lyfts fram i studien. Vygotskijs synsätt på lärande är att lärande och kunskapsinhämtning sker via sociala samspel, detta är någonting som kan diskuteras i relation till vad resultaten i denna studie visar. Två av kategorierna som undersöks i studien är top-down och bottom-up. Vad gäller top-down tillämpas den i tre av fyra arbetsböcker, varav en dessutom tillämpar bottom-up. Det är endast en arbetsbok som enbart tillämpar bottom-up.        Slutsatsen som kan dras baserat på studiens resultat är att innehållet i läromedlen är olika. Trots att flera arbetsböcker använder samma förhållningssätt till läs- och skrivinlärning skiljer sig arbetsböckernas innehåll och upplägg markant. Något annat som kan konstateras är att innehållet i arbetsböckerna till största del består av uppgifter som eleverna ska genomföra enskilt, dock är det även vanligt att flera olika typer av övningar som i olika grad möjliggör interaktion kombineras.
116

Diseño causal de sistema piramidal para aprendizaje colaborativo de los lenguajes de programación

Rosa de Rivera, Verónica Idalia 21 July 2021 (has links)
Esta tesis doctoral ha provocado un cambio de actitud y mentalidad; porque la forma de realizar investigación hasta el momento había sido basada en resultados, es decir, primero se piensa cual será el resultado que se obtendrá o hacia donde se debe llegar, que es lo que se va a producir, utilizando en este caso el método de abajo hacia arriba (bottom up). Sin embargo, este informe se ha realizado bajo una metodología causal, es decir, interesa conocer primeramente cual será el modelo para luego contestar preguntas ¿qué es? y ¿para qué es?, debido a que así se decide un modelo que servirá de marco a la solución y se concretan los objetivos, ya sin ambigüedad, que se persigue alcanzar. Posteriormente se irán contestando las preguntas de ¿cómo?, ¿cuándo? y ¿quién lo hará? Porque así se establece la estructura de la solución, la tecnología que la soportará, y el contexto. Por esa razón, este trabajo aborda aspectos diferentes a las formas tradicionales de resolver un problema en particular, sobre el cual ya se conocen otras soluciones. El método bottom-up puede utilizarse cuando se conoce de antemano la solución por otros casos parecidos; y el top-down es el método general cuando no se tiene mayor conocimiento previo sobre cuál puede ser la solución. De allí que para esta investigación se ha hecho uso del método top-down. Por lo tanto, el grado de Doctora permitirá, resolver problemas haciendo uso de método científico, procurando evitar incorporar arbitrariedad o reduciendo esta a su mínima expresión y, con ello, garantizando la calidad de la solución. Se persigue producir un avance en el estado del conocimiento, en el caso particular de la educación piramidal en el que se ha trabajado bajo un enfoque colaborativo jerarquizado, para la enseñanza de los lenguajes de programación, a través de una plataforma didáctica virtual, en la cual personas con un nivel de educación superior pueden tutorar a otros de nivel educativo inferior para, de esa manera, poder mejorar el proceso de enseñanza-aprendizaje en la Universidad Tecnológica de El Salvador, aunque cabe mencionar que este proyecto podrá ser aplicado a cualquier institución educativa ya sea formal o informal. El objetivo principal es que mediante la educación piramidal y por medio del uso de una plataforma virtual, se pueda dar apoyo en el aprendizaje de cualquier área del conocimiento, que en el caso particular se abordarán los lenguajes de programación, por ser parte fundamental de las carreras de Informática y del área de competencia docente de la autora.
117

Bridging Methodological Gaps in Network-Based Systems Biology

Poirel, Christopher L. 16 October 2013 (has links)
Functioning of the living cell is controlled by a complex network of interactions among genes, proteins, and other molecules. A major goal of systems biology is to understand and explain the mechanisms by which these interactions govern the cell's response to various conditions. Molecular interaction networks have proven to be a powerful representation for studying cellular behavior. Numerous algorithms have been developed to unravel the complexity of these networks. Our work addresses the drawbacks of existing techniques. This thesis includes three related research efforts that introduce network-based approaches to bridge current methodological gaps in systems biology. i. Functional enrichment methods provide a summary of biological functions that are overrepresented in an interesting collection of genes (e.g., highly differentially expressed genes between a diseased cell and a healthy cell). Standard functional enrichment algorithms ignore the known interactions among proteins. We propose a novel network-based approach to functional enrichment that explicitly accounts for these underlying molecular interactions. Through this work, we close the gap between set-based functional enrichment and topological analysis of molecular interaction networks. ii. Many techniques have been developed to compute the response network of a cell. A recent trend in this area is to compute response networks of small size, with the rationale that only part of a pathway is often changed by disease and that interpreting small subnetworks is easier than interpreting larger ones. However, these methods may not uncover the spectrum of pathways perturbed in a particular experiment or disease. To avoid these difficulties, we propose to use algorithms that reconcile case-control DNA microarray data with a molecular interaction network by modifying per-gene differential expression p-values such that two genes connected by an interaction show similar changes in their gene expression values. iii. Top-down analyses in systems biology can automatically find correlations among genes and proteins in large-scale datasets. However, it is often difficult to design experiments from these results. In contrast, bottom-up approaches painstakingly craft detailed models of cellular processes. However, developing the models is a manual process that can take many years. These approaches have largely been developed independently. We present Linker, an efficient and automated data-driven method that analyzes molecular interactomes. Linker combines teleporting random walks and k-shortest path computations to discover connections from a set of source proteins to a set of target proteins. We demonstrate the efficacy of Linker through two applications: proposing extensions to an existing model of cell cycle regulation in budding yeast and automated reconstruction of human signaling pathways. Linker achieves superior precision and recall compared to state-of-the-art algorithms from the literature. / Ph. D.
118

TJÄNSTEPERSONENS HANDLINGSUTRYMME -En studie om tjänstepersonens handlingsutrymme på lokalpolisnivå

Goczkowska, Ewa January 2020 (has links)
Since January 1, 2015, the police authority's largest organizational reform took place, and 21 county police authorities were merged into one unified police authority. The purpose of this was to increase the prerequisites for a stronger operating result with higher quality in the efforts. In connection with the reorganization, they sought to have a more distinct management where the operations would be employee driven. In this study, the official's space for action is studied, and to what extent the public works are considered regarding the expertise and knowledge of the employees at local police level. Through an interview study the officials of the local police level shared the experiences and how the reorganization's impact on the space of action has affected their ability on making decisions. The analysis of the study takes the biggest inspiration from Lisky's street-level bureaucracy theory but also shows elements of the authority's structure, i.e. top-down and bottom-up perspective. The study also takes into account the public officials’ tools of power and analyzes the exercise of power.
119

Kontextabhängigkeit visuelller Wahrnehmung: Der Einfluss der aktuellen Befindlichkeit auf die Wahrnehmung neutraler Stimuli in free-viewing-tasks - Eine Eyetrackingstudie / Visual perception in context: Is viewing behavior in free-viewing tasks with neutral stimuli influenced by emotional state? - An eyetracking study

Hloucal, Teresa-Maria 17 January 2011 (has links)
Objective: Saliency-based theories assume that stimulus features (luminance, edges, texture) shape the hierarchy of perception. Predictions about human viewing behavior point out that highly salient objects or regions of a picture will be perceived first (e.g. Itti et al. 2001). Not much attention is paid to top-down factors such as emotion, motivation and other cognitive functions. The present study analyses the influence of the emotional status on visual perception in free-viewing tasks. Following the hypotheses of the study even in artificial contexts such as viewing neutral pictures in an experiment, top-down factors, such as emotion might influence length of fixation and the number of fixations and saccades. Approaches of visual perception and perception in general should focus more on the individual cognitive aspects of this process. Method: In an eyetracking-study 91 participants viewed neutral and emotional relevant pictures without any task. Five emotional pictures (crime, murder, babies), which were taken from the IAPS (Lang, Bradley & Cuthbert, 2005) were followed by one neutral picture (forest, grass) taken from studies of Peters et al (2005) and Einhäuser et al. (2003). Altogether the subjects viewed 130 pictures. Results: There were significant differences in viewing behavior concerning the neutral pictures subject to the emotional condition. When presented in context with emotional pictures, neutral pictures were fixated longer and less frequently in comparison to the neutral condition. There is evidence to suggest that the emotional context influenced visual attention concerning the neutral pictures in that way that attention for the neutral material was reduced in the context of highly arousing emotional pictures. This leads to the conclusion, that even in experimental setups with simple neutral stimuli the process of visual perception is influenced top-down.
120

Factors regulating the bottom-up guidance of overt visual attention under natural conditions

Acik, Alper 22 June 2015 (has links)
The main goal of the present thesis is to contribute to the study of overt visual attention under natural conditions. All publications included in the thesis employ eye-tracking methodology and local image feature analysis. The particular scientific question posed, if all parts of the thesis are considered together, can be formulated as: What experimental (i.e. experimenter controlled) and pseudo-experimental (e.g. demographic characteristics such as age) variables define, quantify and set limits for bottom-up determinants of fixation election? In this summary, I will bring together the answers to this question obtained during the course of the thesis and try to elucidate their significance in relation to the puzzles and riddles of eye movement research. After presenting an overview of the field, I will show how and to what extent fixation selection is altered as a function of age and as certain stimulus components are modified. Finally, I will argue that visual attention involves varying degrees of reliance on bottom-up cues according to the attending agent’s knowledge that is relevant in a given context.

Page generated in 0.0254 seconds