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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.
1051

Hur påverkas kvinnors hälsa av psykosociala faktorer? : En kartläggning av hälsan bland tillsvidareanställda kvinnor i Sotenäs kommun

Jasniskij, Catarina, Rolander, Leo Marie January 2009 (has links)
Background: Because of the high unhealthy rates among women in the com-mune a project to reduce it have begun. For this reason we have been given the mission from the commune of Sotenäs to study the character of these women's health. Objective: To study the health among permanent employed women in the commune of Sotenäs. Method: Quantitative method. The data have been collected through question-naire survey. The purpose of choosing this method was to be able to see connec-tions between various variables. Result: A large number of women who do not have time to carry out their duties during ordinary working hours have experienced that they are tense and anxious, which means that this mental demand may have affected women's health. The study reveals that many of the women who have not received enough informa-tion from their employer to perform their duties have experienced that they are worn out. The majority of women who lacked in development opportunities at work felt tense. These results imply that small decision latitudes could be one of the explanations of a lower level of health among women. The study identified a number of potential explanations for the sick leave in the commune, as the women felt tense and anxious. Adequate emotional support from friends and family, and a satisfactory everyday social life was related to a low degree of anxiety. A good distribution of practical domestic duties at home was a factor related to a low degree of tension among the permanent employed women in the commune of Sotenäs. / Bakgrund: På grund av det höga ohälsotalet bland kvinnorna i Sotenäs kom-mun har ett arbete med att reducera detta påbörjats. Vi fick därför i uppdrag av Sotenäs kommun att undersöka karaktären på dessa kvinnors hälsa. Syfte: Att kartlägga hälsan bland tillsvidareanställda kvinnor i Sotenäs kommun och hur den påverkas av psykosociala faktorer i arbets- och privatliv. Metod: Kvantitativ metod. Datainsamlingstekniken som tillämpades var enkät. Denna valdes för att kunna genomföra sambandsanalyser mellan olika faktorer. Resultat: Ett stort antal kvinnor som inte hinner utföra sina arbetsuppgifter un-der ordinarie arbetstid uppgav att de är spända och utslitna, vilket innebär att detta psykiska krav kan ha påverkat kvinnornas hälsa. I undersökningen fram-kom vidare att många av kvinnorna som inte mottagit tillräckligt med informa-tion från sin arbetsgivare för att utföra sina arbetsuppgifter att de kände sig ut-slitna. Majoriteten av kvinnorna med bristande utvecklingsmöjligheter i arbetet kände sig spända. Dessa resultat antyder att ett litet beslutsutrymme kan vara en av förklaringarna till en lägre grad av hälsa bland kvinnorna. I undersökningen framkom några möjliga förklaringar till sjukskrivningarna i kommunen, såsom att kvinnorna kände sig spända och utslitna. Ett tillfredsställande emotionellt stöd från vänner och familj, samt ett tillfredsställande vardagligt socialt liv kun-de relateras till en låg grad av oro. En god fördelning av praktiska vardagssyss-lor i hemmet var faktorer, vilka kunde relateras till en låg grad anspänning bland de tillsvidareanställda kvinnorna i Sotenäs kommun.
1052

The experience of living with sensory hyperreactivity (SHR) : Accessibility, financial security and social relationships / Att leva med sensorisk hyperreaktivitet (SHR) : Tillgänglighet, ekonomisk trygghet och sociala relationer

Söderholm, Anna January 2010 (has links)
Purpose: The purpose of the present study was to illuminate how individuals living with SHR, experience its impact on accessibility, financial security and social relationships. Method: A qualitative approach was used. The participants were recruited by advertising on the website for “The network for people with odor intolerance”. The data was collected by written descritive texts from the participants and analysed with qualitative content analysis. Results: The results showed that the informants experienced an extensive lack of accessibility in society. It was difficult to move around in society, to visit public buildings and facilities and it was almost impossible to find a suitable place to live. Regarding financial security they had a reduced income due to difficulties to earn their living in combination with increased expenses because of the disease and they had difficulties to get the support they needed from authorities. This created an insecure financial situation. Further, the findings showed that their social relationships had been affected. Socializing with others had become hard and troublesome, they had become limited in doing social activities and they got support from some but these persons became limited. Six themes permeated the categories in all three content areas: “Being limited”, “Being forced to behave incompatible with your true personality”, “Experiencing a lack of understanding and respect from others”, “Experiencing insecurity”, “Being dependent on others” and “Being forced to choose between the plague and cholera”. / Syfte: Syftet med denna studie var att belysa hur individer som lever med sensorisk hyperreaktivitet (SHR) upplever dess påverkan på tillgänglighet, ekonomisk trygghet och sociala relationer. Metod: Kvalitativ metod användes och deltagarna rekryterades via Internet genom annonsering på nätverket för doftöverkänsligas hemsida. Datainsamlingen skedde genom skrivna berättelser från deltagarna och data analyserades sedan med kvalitativ innehållsanalys. Resultat: Resultatet visade att informanterna upplevde en omfattande brist på tillgänglighet i samhället. Det var svårt att röra sig i samhället, att besöka offentliga lokaler och inrättningar samt att det var nästan omöjligt att hitta en lämplig bostad. Deras ekonomiska trygghet var påverkad genom att de hade minskad inkomst på grund av svårigheter att försörja sig i kombination med ökade utgifter orsakade av sjukdomen samt att de hade svårigheter att få det stöd de behövde från myndigheter. Detta skapade en otrygg ekonomisk situation. Deras sociala relationer hade blivit påverkade av sjukdomen. Att umgås med andra hade blivit jobbigt och besvärligt, deras sociala aktiviteter hade blivit begränsade och de fick stöd av vissa men dessa personer blev då begränsade. Sex teman genomsyrade kategorierna i alla tre innehållsområdena: "Vara begränsad", "Vara tvungen att bete sig oförenligt med sin rätta personlighet", "Uppleva brist på förståelse och respekt från andra", "Uppleva otrygghet", "Vara beroende av andra" och "Vara tvungen att välja mellan pest eller kolera"
1053

Influencia del status social subjetivo en la salud de las mujeres inmigrantes latinoamericanas residentes en la Comunidad de Canabria

Sanchón Macías, Maria Visitación 22 November 2012 (has links)
El propósito de la tesis es estudiar las características socioeconómicas y el estatus social subjetivo de las mujeres inmigrantes y analizar su relación con la salud. Así como, explorar los determinantes del estatus social subjetivo y como las mujeres explican la influencia de los mismos en sus trayectorias de salud. El estudio utilizó metodología cuantitativa y cualitativa. Se observó una asociación débil entre las medidas del estatus socioeconómico y la salud percibida. El estatus social subjetivo fue significativamente asociado con la salud percibida, lo que sugiere que puede ser un indicador relevante para el estudio de las desigualdades en salud Las entrevistas muestran las trayectorias de salud y las desigualdades en los determinantes sociales de salud de las inmigrantes en relación a la población Cántabra. Los determinantes del estatus social subjetivo y de la salud de las mujeres se encuentran, principalmente, en el contexto socioeconómico y político de España.
1054

Antigenic Determinants Of Chicken Riboflavin Carrier Protein: Structural And Functional Aspects

Beena, T K 10 1900 (has links)
Investigations detailed in this thesis constitute a part of the continuing programme of research undertaken in our laboratory on the riboflavin carrier protein (RCP) with partic­ular reference to identification and synthesis of neutralizing antigenic determinants, design of relevant epitope mimetics with improved immunogenic characteristics and relationship between their secondary structures and immunological properties. The riboflavin carrier protein is elaborated as a reproductive stratagem to ensure ade­quate vitamin deposition in the developing oocyte in the chickens. The protein is scrupu­lously conserved through evolution in terms of physico chemical and immunological char­acteristics from fish through birds to mammals, including primates. In rodents and sub­human primates immunization with the heteroantigen viz., chicken egg white RCP leads to functional neutralization of the endogenous maternal protein resulting in curtailment of early pregnancy. Thus, the crucial role of RCP in maintenance of pregnancy is established and the protein identified as a potential candidate vaccine for immimocontraception. Fur­ther studies with the reduced and carboxymethylated (RCM) RCP as the immunogen re­veal that antibodies induced by RCM-RCP are equally effective in bioneutralization of the endogenous protein. So it can be surmised that the native folded structure of RCP is not obligatory for eliciting bioneutralizing antibodies. In an attempt to identify functionally relevant regions of the protein, a panel of monoclonal antibodies (MAbs) have been raised and characterized. One of the MAbs viz., 6J32Ci2 could bring about early fetal resorp-tion when injected to mice with confirmed pregnancies. These results prompted a detail molecular immunological approach to understand underlying mechanisms. The principal aims of the present investigations include: (1) identification of neutralizing epitopes; (2) synthesis of peptidyl sequences incorporating these determinants; (3) an understanding of the structure, antigenic and immunogenic characteristics of these peptides; (4) correlation of conformational and antigenic characteristics; (5) rational design and synthesis of peptide analogs with greater propensity to assume predicted secondary structures; (6) analysis of conformation dependency of peptide antigens and the importance of such conformation in generating an optimal B-cell response; (7) the efficacy of the antibodies elicited by these Peptide antigens in neutralizing endogenous protein with the ultimate aim of designing synthetic vaccines. Chapter 1 of this thesis deals with a general introduction summarizing the current status of knowledge regarding the chemistry and biology of RCP as well as synthetic pep­tides as potential immunogens. Chapter 2 outlines details of the experimental procedures adopted. Chapter 3 describes the results of investigations on the C-terminal fragment (residues 200-219) of cRCR The main consideration in selecting this sequence for the design of a potential peptide-based vaccine relied on the epitopic specificity of the neu­tralizing MAb 6S2C12. Epitope mapping using the Pepscan method revealed that the monoclonal antibody recognizes a core sequence corresponding to residues 203-210 of the cRCP. A 21-residue synthetic peptide (C-21) comprising this epitope was synthesized and antibodies elicited to the peptide conjugated to two different carriers, namely diphtheria toxoid and purified protein derivative (PPD) for T-cell help. In both active and passive immunoneutralization experiments, the peptide specific neutralizing antibodies interfered with the biological function of the protein and hence either protected from pregnancy or caused early fetal resorption in rodents as well as in sub-human primates. The conforma-tional properties of the peptide in aqueous buffers were analyzed from circular dichroism which revealed the absence of any ordered structure in the native C-21 peptide. Theoreti­cal predictions of secondary structure suggested a propensity for an t*-helical structure for this fragment in the native protein. Therefore, influence of the helix-promoting solvent, vizM 2,2,2,trifluroethanol (TFE) on the C-21 peptide was investigated. Addition of TFE resulted in spectral changes with negative bands at 208 and 222 nm and a positive band at 190 rim which are typical of an a-helix. To gain more information on the conformational characteristics of this peptide, it was considered worthwhile to stabilize the native peptide in an a-helical conformation based on simple rational design principles. Towards this end, four analogs of the parent peptide were synthesized and helix stabilization was sought to be achieved by introducing either salt bridges or back-bone conformational constraints such as by incorporating a-amino isobutyric acid at appropriate positions. In all the analogs, the core sequence, recognised by the neutralizing MAb 6B2C12 was maintained intact to ensure induction of antibodies capable of recognizing the native protein. CD spectral analysis of the analog peptides indicated that all the engineered peptides had varying degrees of enhanced helicities as compared to the parent peptide. The immunogenicity of each analog was studied by to the relevant peptide-diphtheria toxoid conjugates and analyzing their reactivities with the native protein by direct and competitive ELISA. The results revealed that these engi­neered conformational analogs axe highly immunogenic eliciting high titers of anti-protein antibodies. The relative affinities of these antibodies to bind cRCP were investigated. The antibodies to peptide analogs had higher affinities for the native protein and a positive correlation was found between the helical content of the peptide antigen in question and the relative affinity of corresponding antibody. The antibodies directed to all the peptide analogs could block the function of RCP resulting in early embryonic resorption when ad­ministered to pregnant mice. An interesting pattern of immunological cross-reactivity has been observed with the native and designed peptides. Antibodies raised to constrained helical analogs could bind the C-21 peptide which is structurally flexible. In contrast, the antibodies raised to the flexible native peptide antigen were inefficient in recognizing the structured peptides. The ability of all the peptide antibody to bind the native protein has been interpreted in terms of a conformationally flexible C-terminus region in cRCP. Chapter 4 details investigations on a 21-residue peptide (N- 21) from the N-terminiis (4-24) of the protein. Selection of this peptidyl sequence relied on theoretical prediction of potential sequential determinants on RCP other than at C-terminus as well as on the outcome of immunoneutralisation experiments using antibodies to egg yolk RCP which lacks the relevant C-terminal determinants. The structure of this peptide in solution was analyzed by two dimensional NMR and CD. NMR experiments revealed the presence of two structured regions in the peptide. Diagnostic nuclear Overhauser effects characteristics of reverse turns or short frayed helical segments over residues 3-9 and 18-21 of the peptide were obtained. CD spectra showed the presence of a strong, negative band at 204 nm over a wide range of solvent conditions, a feature which has been interpreted in terms of a "polyproline Il-like" segment encompassing residues 11-16 which corresponds to an interesting (X-Pro)^ repeat in the N-21 sequence. Specific antibodies were generated to this peptide as a conjugate with diphtheria tox­oid. Administration of the antipeptide antibodies could neutralize the protein in vivo as demonstrated by early embryonic loss in pregnant mice. In limited experiments the anti­peptide antibodies showed propensity to protect bonnet monkeys from pregnancy over a few consecutive ovulatory cycles when titres are maintained elevated by periodic boosting. To address the relationship between peptide structures and antigenicity, epitope mapping of this antipeptide antibodies as well- as the polyclonal antibodies to native RCP was undertaken using the Pepscan method. The results reveal that antigenic regions correspond well to conformationally well-defined elements of structure with the polyproline II-like seg­ment being a common antigenic determinant on both the peptide and the native protein. These observations are suggestive of the involvement of both the N and C-terminal regions of RCP in terms of its binding to putative plasma membrane receptors.
1055

ADHD CHILDREN AND MENTAL HEALTH SERVICE USE: MATERNAL DETERMINANTS

Krizova, Katarina 01 January 2015 (has links)
The current study investigated maternal determinants of mental health service use, namely, individual child therapy, among preadolescent children diagnosed with ADHD. The Behavioral Model of Health Care Utilization (Andersen, 2008) was used as a theoretical framework for the study. Data from the last three rounds of ECLS-K dataset were employed to test a longitudinal model using Bayesian analysis. Socio-demographic variables and maternal mental health were tested as exogenous variables and mother-child relationship variables, discipline variables, and perceived maternal concern about child’s overall behavior and child’s emotional symptoms were tested as intervening variables. Results showed that only maternal mental health remained in the model as an exogenous variable. The effect of mental health on child therapy was mediated by maternal aggravation and maternal concern about overall behavior in one path and by maternal concern about emotional symptoms in another path, suggesting that maternal mental health needs to be considered when attempting to understand help-seeking determinants. Both concern variables were found to have large direct effects on child therapy. The results of the current study showed the importance of maternal mental health and the importance of determinants related to mother-child relationship in a mother’s decision to seek therapy for a child.
1056

從創新擴散理論分階段探討國家寬頻發展影響因素 / Identifying Key Determinants of Broadband Diffusion by Stage Based on Innovation Diffusion Theory

林茂雄, Lin, Mao Shong Unknown Date (has links)
寬頻擴散可促進國家之生產力、就業、經濟成長及國家競爭力等,若能精準找出促進寬頻擴散之關鍵影響因素,將有利於政府集中資源有效率地推動寬頻發展。本研究提出研究問題與假說,以Rogers (2003)及Hall (2006)所提出影響創新擴散速率之社經因素、採用成本、採用效益、網路效應、資訊及不確定性及產業環境等6大因素面向為基礎,蒐集OECD國家及台灣等31國家相關資料,挑選Gompertz模型進行固定寬頻擴散Panel資料迴歸分析,發現各因素在全期及不同擴散階段有不同之顯著性與影響程度,表示分階段分析有其必要性。擴散初期之關鍵影響因素為收入、教育水準、平台競爭程度、人口密度及實施LLU累積年度等5項,而擴散後期之關鍵影響因素為寬頻價格、網際網路內容、決定採用時固定寬頻用戶比例、撥接用戶比例及擁有PC家庭比例等5項,可作為政府及業者於不同擴散階段精準投入資源以有效推動寬頻擴散之參考。 本研究續以前述分析結果選取日本、南韓、美國、丹麥、瑞士及台灣進行實際擴散比較,確認前述關鍵影響因素挑選之有效性。擴散初期,台灣有高人口密度優勢,若能提早推動寬頻並推動促進競爭措施,可促進初期之快速擴散。擴散後期,台灣國際排名退步,原因為寬頻價格過高,故此階段政府及業者應特別確保寬頻價格能夠使潛在採用者有能力並願意付費採用,才能促使寬頻持續有效擴散。 最後,本研究採用與固定寬頻相同迴歸分析模型對FTTX及行動寬頻分別進行分析後,有關行動寬頻,教育水準、寬頻價格、決定採用時行動寬頻用戶比例、人口密度、網際網路內容、使用固定寬頻語音服務比例、決定採用時FTTX用戶比例及使用網際網路家庭比例等8項變數有顯著效應;有關行動寬頻,收入、寬頻價格、網際網路內容、決定採用時行動寬頻用戶比例、使用網際網路家庭比例及人口密度等6項變數有顯著效應。因此,政府及業者若擬促進特定寬頻服務發展,仍須針對其服務特性推動特定之政策或策略。其中,寬頻價格、網際網路內容、網路效應及使用網際網路家庭比例等4項因素對FTTX及行動寬頻服務之影響類似,而此4個因素與固定寬頻後期擴散之關鍵影響因素較相近,因此,對於已存在市場的服務,即使是後來以較佳品質或功能之新服務型式提供,新服務之關鍵影響因素仍較接近已存在市場服務關鍵因素。 總之,本研究不同於過去文獻,以創新擴散理論為基礎,以國家層級資料量化分析與探討寬頻擴散之關鍵影響因素,除分別提供政策及管理建議供政府及業者參考外,亦補強Rogers (2003)及Hall (2006)所提出創新擴散理論未釐清與比較創新擴散影響因素在不同擴散階段影響之不足。 / Broadband diffusion may enhance innovation, productivity, employment, economic growth, and, ultimately, national competitiveness. If key determinants for broadband diffusion are identified, governments can align its resources with them to effectively promote the diffusion. Based on the determinants of the diffusion rate identified by Rogers (2003) and Hall (2006), this research compiled data available about OECD countries as well as Taiwan to implement overall and staged panel regressions on fixed broadband diffusion by adopting Gompertz model. The findings indicate that the significance of the determinants varies between overall and staged analysis, which consequently justifies the necessity of a staged analysis. The key determinants in the early stage are income, education level, platform competition, population density, and the accumulated years of implementing LLU policy; however, in the late stage they are broadband price, Internet content, network effect, the penetration of dial-up users, and percentage of household with computer. Governments may more accurately promote broadband diffusion according to different key determinants in different stages. This research further compared the real fixed broadband diffusion of Japan, South Korea, USA, Denmark, Switzerland, and Taiwan based on the previous analysis results. The findings generally justify the choice of key determinants in the previous analysis. In the early stage, Taiwan had the advantage of high population density. If the government could have promoted fixed broad banded services and market competition earlier, the penetration would have grown much faster. In the late stage, since the broadband price was too high in Taiwan, its international ranking of fixed broadband penetration declined. Therefore, in order to further promote the diffusion of fixed broadband, the government should have ensured that the price was low enough to convince the potential adoptors to purchase broadband services. Finally, this research adopted the same approach as that of previous fixed broadband to analyze the diffusion of FTTX and mobile broadband, respectively. Education level, broadband price, network effect of FTTX, network effect of mobile broadband, Internet content, population density, percentage of household with computer, and the penetration of fixed VOIP users have significant effect on FTTX diffusion. However, income, broadband price, network effect of mobile broadband, Internet content, population density, and percentage of household with computer have significant effect on mobile broadband diffusion. Therefore, governments or operators should tailor their policies or strategies for specific services. The effects of broadband price, Internet content, network effect, and percentage of household with computer are similar in both FTTX and mobile broadband, and they are also similar to the key determinants of fixed broadband diffusion in the late stage. Therefore, even though a new service with better quality or function is introduced in an existing market, its key determinants are more similar to those of the existing service depending on its diffusion stage. In conclusion, different from previous research, this one applied national-level data to quantatively analyzed and explore the key determinants of broadband diffusion based on innovation diffusion theory. The research findings not only propose policy and management suggestions to governments and service providers, but also supplement the the theory proposed by Rogers (2003) and Hall (2006), which did not identify and compare the determinants of innovation in different diffusion stages.
1057

Who died, where, when and why? : an investigation of HIV-related mortality in rural South Africa

Mee, Paul January 2015 (has links)
Background South Africa has experienced the most severe consequences of the HIV/AIDS pandemic. Every community has been affected in some way, many experiencing huge increases in mortality,particularly before antiretroviral therapies (ART) were readily available. However, the micro-level understanding of the HIV epidemic in South Africa is weak, because of a lack of detailed data for most of the population. This thesis is based on detailed individual follow-up in the Agincourt Health and Demographic Surveillance Site (HDSS) located in the Agincourt subdistrict of Mpumalanga Province and investigates micro-level determinants of HIV epidemiology and the impact of treatment provided. Methods The Agincourt HDSS has followed a geographically defined population since 1992,approximately the time when the HIV/AIDS epidemic first became apparent. This population based surveillance has included capturing details of all deaths, with cause of death determined by verbal autopsy, as well as the geographical location of individual households within the overall Agincourt area. Background information on the roll-out of ART over time was also recorded. Results A comparison immediately before and after the major roll-out of ART showed a substantial decrease in HIV-related mortality, greater in some local communities within the area than others. Individual determinants associated with a decreased risk of HIV/AIDS mortality included proximity to ART services, as well as being female, younger, and in higher socioeconomic and educational strata. There was a decrease in the use of traditional healthcare sources and an increase in the use of biomedical healthcare amongst those dying of HIV/AIDS between periods before and after the roll-out of ART. Conclusions Understanding micro-level determinants of HIV/AIDS infection and mortality was very important in terms of characterising the overall epidemic in this community. This approach will enable public health interventions to be more effectively targeted towards those who need them most in the continuing evolution of the HIV/AIDS epidemic.
1058

Precursors and prices : structuring the Quebec synthetic drug market

Ouellet, Marie 08 1900 (has links)
Information recueillie sur les marchés des drogues de synthèse est beaucoup moins avancée que les études sur d'autres marchés de drogues illicites. La classification relativement récente des drogues de synthèse comme substances illicites, couplée avec ses caractéristiques distinctes qui empêchent son observation, a entravé le développement d’évaluations complètes et fiables des caractéristiques structurelles des marchés. Le but de cet article est de fournir un aperçu fiable sur la dynamique interne du marché des drogues synthétiques, en particulier sur ses caractéristiques structurelles et organisationnelles. En utilisant l'information obtenue à partir de 365 drogues de synthèse saisies par les policiers pendant un an, cette étude sera la fusion de deux techniques, soit la composition des drogues illicites et des analyses économiques, afin de tirer des évaluations fiables des caractéristiques structurelles du marché du Québec de drogues synthétiques. Les résultats concernant l'analyse de la composition des drogues indiquent que le marché des drogues synthétiques au Québec est probablement composé d'un nombre élevé de petites structures, ce qui indique un marché compétitif. L'analyse économique a également fourni des informations complémentaires sur le marché des drogues. Selon la région géographique les couts de la production et les relations entre trafiquant et consommateur influencent le prix des drogues. Les résultats de cette recherche mettent l'accent sur la nécessité de concevoir des politiques qui tient compte des différences régionales dans la production de drogue et reflète la nature compétitive de ce marché. / Research gathered on synthetic drug markets trails behind studies on other illegal drug markets. Synthetic drug's relatively recent classification as an illicit substance, coupled with its distinct characteristics that insulate it from detection has hindered the development of reliable assessments of the markets structural features. The purpose of this study is to provide reliable insight into the inner dynamics of Quebec’s synthetic drug industry, focusing on its organizational features. Using information derived from 365 synthetic drugs seized by law enforcement over a one year period, this study will merge two techniques, drug composition and economic analyses, under a common framework to derive reliable and comprehensive assessments of the structure of Quebec's synthetic drug market. Drug composition analysis examines the drug’s chemical and physical profile to make inferences about the market structure while the economic analysis examines price determinants for the same market, providing further insight into its dynamics and distinctive features. Findings from the drug composition analysis indicate that the synthetic drug market in Quebec is likely to be composed of a high number of small structures, indicating a competitive market. The economic analysis provided complementary information, finding that both differential production costs and trafficker-consumer relations may influence price variations, depending on the region. This study concludes by emphasizing that drug composition analysis should be diligently pursued by both researchers and enforcement organizations alike to effectively target and enhance our understanding of the intricate processes that underlie the synthetic drug market.
1059

L’étude des déterminants et des effets de la formation au sein des entreprises canadiennes : au-delà de la productivité

Bernier, Amélie 11 1900 (has links)
Les milieux de travail canadiens présentent des visages diversifiés et en pleine mutation. En raison de facteurs tels que les nouvelles technologies, la mondialisation, l’économie du savoir ou encore l’évolution démographique, la transformation des entreprises canadiennes passe par une main-d’œuvre qualifiée, adaptable et de qualité. Notre recherche s’inscrit dans le cadre des études s’intéressant aux comportements des entreprises en matière d’investissement en capital humain au Canada. Nous avons retenu un cadre théorique qui est constitué principalement de la théorie du capital humain, de celle des ressources internes et de l’approche des coûts et des bénéfices. Pour les fins de notre recherche, nous retenons une approche quantitative longitudinale, en utilisant des données secondaires issues du questionnaire des employeurs de l’Enquête sur le milieu de travail et les employés pour les années 1999 à 2005 inclusivement. La nature longitudinale de l’EMTE permet de corriger pour les biais liés à l’hétérogénéité non observée des firmes et à l’endogénéité possible de la variable de formation. Notre étude se divise globalement en trois articles. Dans les deux premiers cas, les dépenses en formation sont considérées comme une variable explicative de la productivité et du taux de roulement des employés. Dans le troisième cas, les dépenses de formation constituent la variable dépendante à l’étude. Le premier article examine l’effet des investissements en formation sur la productivité des entreprises canadiennes. La littérature scientifique traitant de l’impact de la formation sur la performance des entreprises continue de s’accroître dû aux nouvelles techniques d’estimations, à la disponibilité des données, et à l’intérêt grandissant pour le capital humain. Les résultats partiels des études antérieures montrent la possibilité que les retours des investissements réalisés en formation puissent avoir des effets au-delà de l’année courante. Sur le plan théorique, cette hypothèse a du sens, mais au niveau empirique il semble que les liens formels entre la formation et la productivité des entreprises ne sont pas clairement identifiés. Nos résultats montrent que les investissements en formation réalisés avec trois années de retard engendrent des effets positifs et significatifs sur la productivité à court et à moyen termes. L’interaction entre les différents types d’investissements permet de vérifier l’hypothèse à l’effet que les investissements en capital physique et en capital humain soient complémentaires et se supportent mutuellement. Après avoir procédé à l’estimation de l’effet des dépenses en formation structurée sur la productivité des entreprises, nous nous demandons pour quelles raisons les employeurs demeurent réticents quant aux retours des investissements en formation ? Dans le cadre de cette seconde réflexion, nous nous intéressons à deux dimensions de l’estimation du roulement, à savoir le roulement de nature volontaire et une mesure de l’optimum. Les résultats obtenus quant à l’effet des dépenses en formation structurée par employé sur les taux de roulement volontaire et optimal montrent que la relation est positive dans les deux cas. Cet article vise également à vérifier si différents outils organisationnels associés aux relations industrielles peuvent avoir un effet sur la réduction du taux de roulement volontaire des employés. Nos résultats montrent aussi que la présence syndicale et la perception d’un bon climat de travail traduisent dans un sens, un environnement dans lequel l’employeur et les employés ont des intérêts communs pour la poursuite de mêmes objectifs. Dans le cadre du troisième article, nous examinons certains déterminants des investissements en formation structurée au sein des milieux de travail. Nos résultats montrent qu’une entreprise de grande taille, qui investit davantage en capital physique par employé par rapport à la moyenne, au sein de laquelle un grand pourcentage de travailleurs utilisent un ordinateur, où il y a une proportion élevée de nouvelles embauches et pour laquelle l’employeur introduit un système cohérent de pratiques dépense davantage en formation structurée qu’une entreprise qui ne possède pas ces caractéristiques, toutes choses égales par ailleurs. Ces résultats permettent de discuter également de la complémentarité des facteurs faisant partie d’un cercle vertueux de croissance des entreprises pouvant déterminer les investissements en formation. / Canadian workplaces face diversified and new challenges. Globalization, technological change, knowledge-based economy, demographic trends and all levels of government initiatives significantly affect our workplaces. As a result, the transformations of the work environment are based on skilled and flexible labour. Our research summarizes the literature on job-related training and the effects of these investments on different workplaces. Our research also elaborates empirical explanations and policy implications based on the outcome of these existing studies. The proposed theoretical framework is based on the human capital theory, the resource-based theory of the firm, and the cost-benefit approach. The longitudinal panel data used in this research are drawn from the Statistics Canada’s Workplace and Employee Survey (WES) over the years 1999 to 2005 inclusively. The longitudinal nature of the WES allows us to address issues of endogeneity of inputs including human capital and unobserved heterogeneity of establishments as well as omitted variable bias. Our study is divided into three articles. In the first two articles, expenses in training are considered to be an explanatory variable of both productivity and the rate of employee turnover. In the third article, an empirical model is developed using training expenditures within the firm as the dependent variable. Among consulted studies dealing with the possible impact of the training on the productivity, several treat longitudinal character of the data, but few consider the lagged effects of the training. Partial results of the previous studies show that returns of investments in training could have effects beyond the common year. As part of the first article, we examine the impact of training on productivity which is estimated through a Cobb-Douglas production function with a distributed lags on training expenditures and capital investments. We take advantage of the longitudinal data by estimating a model that considers the impact on productivity of both of training expenditures and the investments in physical capital. Because of the interaction between investments in training and physical capital, the assumption that, investments in physical capital and human capital are complementary and support themselves mutually can be tested. Our results show that investments in training have positive effects on productivity which are spread out over a three years period. After completing the above estimates, we wondered why some employers hesitate before investing in training. As part of this reflexion, we analyse the incidence of training expenditures on labour turnover. We are interested in two dimensions, namely: the voluntary turnover and a measure of the optimal level of employee turnover. Our main finding is that training expenditures increase voluntary turnover as well as the gap between observed and estimated optimal level of employee turnover. Our findings also show that the presence of a union and the perception of a good working climate that result into an environment in which both employer and employees achieve common objectives help to reduce turnover. Finally, in the third article, we examine some determinants of the training investments in the Canadian workplaces. We focus on the intensity of on-the-job training where intensity refers to the training expenditures. We find that a larger firm size, who invests more in physical capital by employee than the average, within which a great percentage of workers use a computer, where there is a high proportion of new recruiting and for which the employer introduces a consistent system of practices, invests more in on-the-job training than a firm without the above characteristics, other things being equal. Our findings also suggest the existence of a «virtuous circle». In other words, these factors act as a self-reinforcing mechanism which futher boosts investments in training.
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Un modèle explicatif des niveaux de réglementation des États américains en matière de production de gaz à effet de serre

Guimond, David 11 1900 (has links)
Ce travail contribue au champ d’études sur l’adoption de politique publique des États américains en étudiant quantitativement leurs réactions à l’enjeu du réchauffement climatique. Suivant l’approche des déterminants internes, des facteurs économiques, politiques et environnementaux sont utilisés pour expliquer la densité réglementaire étatique limitant la production de gaz à effet de serre. La variable dépendante constitue la principale contribution de ce travail puisqu’elle incarne une revue exhaustive des options législatives adoptées par les États américains et les regroupe en six catégories. Les déterminants internes identifiés permettent d’expliquer pourquoi certains États sont des instigateurs ou des retardataires dans le dossier du réchauffement climatique. Les principaux facteurs explicatifs sont la présence d’une population idéologiquement libérale et de groupes d’intérêts environnementaux forts. / This paper contributes to the state policy adoption literature by studding the legislative response of the American states to global warming. We quantitatively test hypotheses drawn from internal determinants models of policy adoption to explain why some states are leaders and other laggards in climate change. Our dependent variable is a grouping of all the important types of measures adopted by states to limit the production of greenhouse gases in six categories. To explain the number of measures adopted by each state, we include in our model economic, political and geographic variables that have an impact on the adoption of climate change policies. The results show that the strongest explanatory factors are the presence of an ideologically liberal population and of strong environmental interest groups.

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