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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

Evaluation de l'efficacité des établissements secondaires. Analyse des indicateurs favorisant la plus-value pédagogique des établissements. Etude réalisée en République Démocratique du Congo

Tukanda Manya, Daniel 11 May 2010 (has links)
La présente étude examine la problématique de la variation des perfor-mances scolaires des élèves dans les établissements secondaires. Son but est de rechercher les caractéristiques des écoles « efficaces » et « équitables ». Compte tenu des distorsions importantes dans les conclusions des recherches « processus-produits » qui décrivent les relations entre les facteurs investis(inputs) et le produit (output) dans le domaine de l’éducation et au regard de la littérature interna-tionale mettant en relief une multitude de variables(macro et micro-sociologiques) qui semblent influencer la réussite scolaire des élèves, nous avons tenu à mettre en évidence dans le contexte de l’enseignement en RDC certaines variables d’ordre scolaire pouvant amener les écoles à la réalisation de la plus-value pédagogique. Ces dernières décennies, il y a certes une prolifération des établissements d’enseignement jamais existée dans le système éducatif congolais. Mais, ce qui est frappant et étonnant dans ce système éducatif aujourd’hui est le fait de la différence de niveau très remarquable entre élèves de même profil fréquentant les établissements scolaires différents. Leurs élèves soumis à des tests standards, on constate que certains d’entre ces établissements réalisent la plus-value pédagogique alors que d’autres réalisent la moins-value. Quelles sont les variables d’ordre scolaire pouvant expliquer cette différence de rendement ? Telle est la question principale à laquelle cette étude tente d’apporter quelques éléments de réponse. Face à cette question, l’hypothèse générale que nous avons émise est qu’il existe un « effet-établissement » qui influence les acquisitions de tous les profils d’élèves en classe. Ce travail s’articule sur deux parties principales emboîtées. La première partie explore quelques théories sur la réussite ou l’échec scolaire des élèves et examine les résultats de quelques études empiriques mettant en relief les effets relatifs de scolarisation. La deuxième partie est consacrée à la description de la démarche méthodologique de notre recherche et à l’analyse des résultats des élèves à nos tests de français et de mathématique. Elle est aussi consacrée à l’analyse des réactions des enseignants et du personnel de direction scolaire à notre questionnaire relatif aux facteurs prioritaires sur lesquels on peut à l’instant porter en tout premier lieu une attention particulière afin d’améliorer le rendement scolaire. Par une analyse des résultats de 605 élèves de dix-huit établissements de l'enseignement secondaire ayant passé nos tests et aussi par une analyse des réponses à notre questionnaire auquel 122 enseignants et 49 personnel ( conseillers, proviseurs et chefs d’établissement ) de direction des établissements concernés par cette étude ont réagi, nous avons tenté de mettre en évidence certaines caractéristiques scolaires pouvant entraîner la réalisation de la plus et/ou moins-value pédagogique dans une école. D’une manière générale, les résultats de cette étude montrent que la différence de performances des élèves apprenant dans les établissements différents semble être liée à certaines caractéristiques propres aux établissements scolaires et à des pratiques enseignantes. Vu les résultats présentés par les élèves des classes identifiées comme étant « efficaces » et « équitables », les caractéristiques (celles mises en évidence) des écoles organisant ces classes donnent à penser que celles-ci exercent un effet sur les acquisitions des élèves.
42

Expression of anxiety-related genes, including the cytoplasmic polyadenylation element binding protein (CPEB), in the rat limbic system

Van Cleemput, Jamie Michelle 03 May 2006
Anxiety disorders are one of the most prevalent mental disorders in the world. While normal anxiety serves as an important protective mechanism, pathological anxiety characteristic of an anxiety disorder is both maladaptive and disruptive. The majority of studies have focused on the neurotransmitter systems associated with the actions of known anxiety drugs. This focus may likely limit the exploration of mechanisms underlying anxiety disorders. This project aims to examine changes in gene expression that may underlie higher or lower levels of inherent anxiety. Using a well-established behavior test for anxiety, the elevated plus maze, we identified male Wistar rats exhibiting inherently high- or low-anxiety levels. Brain regions known to mediate anxiety, the amygdala, hippocampus and nucleus accumbens, were dissected and total mRNA isolated. The mRNA was converted to cDNA via reverse transcription-polymerase chain reaction (RT-PCR). Then, the cDNA was used in suppression subtractive hybridization, a technique used to compare two complete populations of cDNAs and identify cDNAs that are upregulated in one population in relation to the other. In this project suppression subtractive hybridization was used to compare high- and low-anxiety cDNA populations. The upregulated cDNAs were amplified in a PCR reaction that enables rare transcripts to be identified. The PCR products from the suppression subtractive hybridization were cloned and used to create two cDNA libraries for high- and low-anxiety related genes. These clones were sequenced to show over 1000 genes upregulated in high- and low-anxiety. The gene list was then subjected to bioinformatic analysis to identify one candidate to be studied in further detail. <p>The prion protein was identified as a potential candidate. Examination of the literature sparked an interest in studying other prion-like proteins, more specifically the cytoplasmic polyadenylation element binding protein (CPEB). The CPEB protein is a potent regulator of mRNA translation in both mature oocytes and the adult brain. While unphosphorylated the CPEB protein keeps specific mRNAs dormant in the cytoplasm. In its phosphorylated form CPEB catalyzes polyadenylation of the mRNA, leading to protein synthesis. p*PCR was used to show the presence of CPEB mRNA transcripts in the rat hippocampus. CPEB protein expression was examined in the brain samples isolated from control, high- and low-anxiety rats. It was found that CPEB was significantly upregulated in high- and low-anxiety rats compared to control. The protein expression of an upstream kinase, Aurora A kinase, and a downstream target, Calcium/Calmodulin Dependent Kinase II (CaMKII), was also investigated. The results from Aurora A kinase were inconclusive. CaMKII, on the other hand, was significantly upregulated in high-anxiety over both control and low-anxiety. These results suggest that CPEB may catalyze increased translation of mRNAs in high-anxiety while acting as a repressor of those same mRNAs in low-anxiety. <p>Recent studies have suggested that CPEB protein plays an important role in synaptic plasticity. The regulation of synaptic plasticity, and its impact on learning and memory, is believed to be a key mechanism behind the maintenance of anxiety disorders. Therefore the results of this study suggest a new molecular mechanism in the development of anxiety disorders.
43

Genomförande och framtagning av metod för tidsstudier vid LB-Hus AB

Nilsson, Viktor January 2008 (has links)
Syftet med detta examensarbete var att bestämma enhetstider som används för prissättning och produktionsplanering av ytterväggar vid LB-Hus AB. Syftet var också att utforma en standard för kommande tidmätningar vid förtaget. Som hjälpmedel vid tidmätningarna har programvaran Umt-Plus använts. För att underlätta vid kommande mätningar vid företaget har enklare instruktioner för de vanligaste funktionerna i programmet tagits fram och arbetsgången noggrant dokumenterats. Under genomförandet av tidmätningarna har produktionsprocessen granskats och de problem som har uppmärksammats är bl a. oklarheter i ritningsunderlagen som snabbt orsakar störningar i produktionen och att de beredningsmissar som förekommer ofta resulterar i onödigt dubbelarbete. De uppmätta enhetstiderna stämmer väl överens med de tider som i dagsläget används av företaget. Dock har bara en linje undersökts och vidare undersökningar bör göras vid de andra linjerna för att med säkerhet kunna bekräfta de tider som används. Vid studien har verkningsgraden vid linjen uppmätts till 74 % och det är lägre än vad LB-Hus AB använder sig av vid sin kalkylering. Skillnaden mellan verklig verkningsgrad och den antagna kan vara en orsak till att det i nuläget behövs en hel del övertid för att hinna med den produktion som läggs ut i fabriken.
44

Expression of anxiety-related genes, including the cytoplasmic polyadenylation element binding protein (CPEB), in the rat limbic system

Van Cleemput, Jamie Michelle 03 May 2006 (has links)
Anxiety disorders are one of the most prevalent mental disorders in the world. While normal anxiety serves as an important protective mechanism, pathological anxiety characteristic of an anxiety disorder is both maladaptive and disruptive. The majority of studies have focused on the neurotransmitter systems associated with the actions of known anxiety drugs. This focus may likely limit the exploration of mechanisms underlying anxiety disorders. This project aims to examine changes in gene expression that may underlie higher or lower levels of inherent anxiety. Using a well-established behavior test for anxiety, the elevated plus maze, we identified male Wistar rats exhibiting inherently high- or low-anxiety levels. Brain regions known to mediate anxiety, the amygdala, hippocampus and nucleus accumbens, were dissected and total mRNA isolated. The mRNA was converted to cDNA via reverse transcription-polymerase chain reaction (RT-PCR). Then, the cDNA was used in suppression subtractive hybridization, a technique used to compare two complete populations of cDNAs and identify cDNAs that are upregulated in one population in relation to the other. In this project suppression subtractive hybridization was used to compare high- and low-anxiety cDNA populations. The upregulated cDNAs were amplified in a PCR reaction that enables rare transcripts to be identified. The PCR products from the suppression subtractive hybridization were cloned and used to create two cDNA libraries for high- and low-anxiety related genes. These clones were sequenced to show over 1000 genes upregulated in high- and low-anxiety. The gene list was then subjected to bioinformatic analysis to identify one candidate to be studied in further detail. <p>The prion protein was identified as a potential candidate. Examination of the literature sparked an interest in studying other prion-like proteins, more specifically the cytoplasmic polyadenylation element binding protein (CPEB). The CPEB protein is a potent regulator of mRNA translation in both mature oocytes and the adult brain. While unphosphorylated the CPEB protein keeps specific mRNAs dormant in the cytoplasm. In its phosphorylated form CPEB catalyzes polyadenylation of the mRNA, leading to protein synthesis. p*PCR was used to show the presence of CPEB mRNA transcripts in the rat hippocampus. CPEB protein expression was examined in the brain samples isolated from control, high- and low-anxiety rats. It was found that CPEB was significantly upregulated in high- and low-anxiety rats compared to control. The protein expression of an upstream kinase, Aurora A kinase, and a downstream target, Calcium/Calmodulin Dependent Kinase II (CaMKII), was also investigated. The results from Aurora A kinase were inconclusive. CaMKII, on the other hand, was significantly upregulated in high-anxiety over both control and low-anxiety. These results suggest that CPEB may catalyze increased translation of mRNAs in high-anxiety while acting as a repressor of those same mRNAs in low-anxiety. <p>Recent studies have suggested that CPEB protein plays an important role in synaptic plasticity. The regulation of synaptic plasticity, and its impact on learning and memory, is believed to be a key mechanism behind the maintenance of anxiety disorders. Therefore the results of this study suggest a new molecular mechanism in the development of anxiety disorders.
45

A Procedural Study of Trade Integration between China and ASEAN

Wan, Wei-chun 20 July 2011 (has links)
Trade Integration between China and ASEAN, which is behind North American Free Trade Agreement and European Union. It will become the third largest economy in the world. The prupose of this study tries to look for ¡§substantial¡¨ strategies and methods of China-ASEAN free trade area between China and ASEAN. In the conclusion, this study discovers China-ASEAN free trade area is an important tool for China, because of China could use it achieving regional stability, resource strategies, South-West development, and connection of East Asia integration. In process of trade integration, China not only adds trade and investment in Southeast Asia, but also provides economic assistance and joins ASEAN plus one. To came to China¡¦s WinWin pruposes.
46

none

Chen, Chin-chao 15 June 2005 (has links)
none
47

New strategic method to tune equation-of-state to match experimental data for compositional simulation

Al-Meshari, Ali Abdallah 17 February 2005 (has links)
Since the plus fraction of reservoir fluids has some uncertainty in its molecular weight and critical properties, equation-of-state, EOS, are generally not predictive without tuning its parameters to match experimental data. Tuning of the EOS is found to be the best method for improving the predictions of compositional reservoir simulators. The proposed strategy for tuning EOS consists of seven steps: (1) split the laboratory plus fraction to single carbon number groups, SCN, usually up to SCN 44; the last component will be C45+, (2) use set of correlations to calculate the critical properties and acentric factor for each SCN group, (3) match the saturation pressure at reservoir temperature by altering the measured value of the molecular weight of the plus fraction using the extended composition, (4) group SCN groups to multiple carbon number groups, MCN, (5) assign critical properties and acentric factor for each MCN group, (6) rematch the saturation pressure at reservoir temperature using the grouped composition, and (7) match the volumetric data by regressing on volume shift parameters of all components in grouped composition. This research shows an accurate method to split the plus fraction to SCN groups. The most accurate set of correlations to calculate the critical properties and acentric factor for each SCN group that will result in a small adjustment for the molecular weight of the plus fraction when saturation pressure is matched using the extended composition. The proposed strategy groups the extended composition to eight pseudocomponents. The binary interaction coefficients between hydrocarbons and between hydrocarbons and non-hydrocarbons are set to zero which dramatically reduces the simulation time. The strategy proposed in this research for tuning EOS to match experimental data has been tested for a wide range of C7+ mole% (4 – 25) which covers gas condensate and volatile oil samples. Also, using this strategy to tune EOS at reservoir temperature will accurately predict the fluid properties at separator conditions and saturation pressures at different temperatures. The scope of this research is to come up with an accurate and systematic technique for tuning an EOS for use in compositional simulation.
48

Genomförande och framtagning av metod för tidsstudier vid LB-Hus AB

Nilsson, Viktor January 2008 (has links)
<p>Syftet med detta examensarbete var att bestämma enhetstider som används för prissättning och produktionsplanering av ytterväggar vid LB-Hus AB. Syftet var också att utforma en standard för kommande tidmätningar vid förtaget.</p><p>Som hjälpmedel vid tidmätningarna har programvaran Umt-Plus använts. För att underlätta vid kommande mätningar vid företaget har enklare instruktioner för de vanligaste funktionerna i programmet tagits fram och arbetsgången noggrant dokumenterats.</p><p>Under genomförandet av tidmätningarna har produktionsprocessen granskats och de problem som har uppmärksammats är bl a. oklarheter i ritningsunderlagen som snabbt orsakar störningar i produktionen och att de beredningsmissar som förekommer ofta resulterar i onödigt dubbelarbete.</p><p>De uppmätta enhetstiderna stämmer väl överens med de tider som i dagsläget används av företaget. Dock har bara en linje undersökts och vidare undersökningar bör göras vid de andra linjerna för att med säkerhet kunna bekräfta de tider som används. Vid studien har verkningsgraden vid linjen uppmätts till 74 % och det är lägre än vad LB-Hus AB använder sig av vid sin kalkylering. Skillnaden mellan verklig verkningsgrad och den antagna kan vara en orsak till att det i nuläget behövs en hel del övertid för att hinna med den produktion som läggs ut i fabriken.</p>
49

Réalité de la prescription des hypolipémiants chez les personnes âgées de plus de 80 ans étude en médecine générale ambulatoire, dans un secteur géographique limité /

Lapierre, Frédérique Masson, Arnaud. January 2008 (has links) (PDF)
Thèse d'exercice : Médecine : Nancy 1 : 2008. / Titre provenant de l'écran-titre.
50

An In-Vitro Study Assessing the Effect of Smear Layer on Root Canal Microleakage.

Elnour, Mutasim Hassan. January 2008 (has links)
<p> <p>&nbsp / </p> </p> <p><font face="Times New Roman" size="3">The aim of this study was to compare the sealing ability of AH Plus sealer to the canal wall in the presence and absence of the smear layer.</font></p>

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