936 resultados para Non-negative sources


Relevância:

30.00% 30.00%

Publicador:

Resumo:

The paper extends the time-series financial news data set constructed by Garcia (2013) and uses it to examine whether financial news predicts returns of Islamic stocks differently compared to non-Islamic (conventional) stocks. We find that they do. First, while both positive and negative worded news predict most Islamic and conventional stock returns, positive words have a larger impact on both types of stock returns. Second, shock to returns from financial news reverses only in part for some stocks. Third, for a mean-variance investor, investing in Islamic stocks is relatively more profitable than investing in the corresponding conventional stocks. Fourth, we show that profits are robust to a range of time-series risk factors, namely, market risk, size-based risk, and momentum-induced risk.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Animal movements may contribute to the spread of pathogens. In the case of avian influenza virus, [migratory] birds have been suggested to play a role in the spread of some highly pathogenic strains (e.g. H5N1, H5N8), as well as their low pathogenic precursors which circulate naturally in wild birds. For a better understanding of the emergence and spread of both highly pathogenic (HPAIV) and low pathogenic avian influenza virus (LPAIV), the potential effects of LPAIVs on bird movement need to be evaluated. In a key host species, the mallard Anas platyrhynchos, we tested whether LPAIV infection status affected daily local (< 100 m) and regional (> 100 m) movements by comparing movement behaviour 1) within individuals (captured and sampled at two time points) and 2) between individuals (captured and sampled at one time point). We fitted free-living adult males with GPS loggers throughout the autumn LPAIV infection peak, and sampled them for LPAIV infection at logger deployment and at logger removal on recapture. Within individuals, we found no association between LPAIV infection and daily local and regional movements. Among individuals, daily regional movements of LPAIV infected mallards in the last days of tracking were lower than those of non-infected birds. Moreover, these regional movements of LPAIV infected birds were additionally reduced by poor weather conditions (i.e. increased wind and/or precipitation and lower temperatures). Local movements of LPAIV infected birds in the first days of tracking were higher when temperature decreased. Our study thus demonstrates that bird-assisted dispersal rate of LPAIV may be lower on a regional scale than expected on the basis of the movement behaviour of non-infected birds. Our study underlines the importance of understanding the impact of pathogen infection on host movement in order to assess its potential role in the emergence and spread of infectious diseases.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Au Québec, la mémoire de la Grande Guerre renvoie automatiquement à une vision douloureuse de l’événement. Créée et alimentée par des souvenirs à forte charge émotive tels la crise de la conscription, les émeutes de Pâques et l’inhospitalité de l’Armée canadienne envers les combattants canadiens-français, cette mémoire est non seulement négative, mais également victimisante. Dans leur récit du conflit, les Québécois ont pris pour vérité une version qui les dépeint comme boucs émissaires des Canadiens anglais. Acceptée et intégrée autant dans l’historiographie que dans la croyance collective, cette thèse du Canadien français opprimé n’a jamais été questionnée. Ce mémoire entend donc revisiter cette version en la confrontant aux sources laissées par les contemporains. En utilisant la presse anglophone et les témoignages de combattants, il lève le voile sur le regard anglo-saxon envers les Canadiens français et dans une plus large mesure, sur les relations interethniques pendant la guerre. Il témoigne de la réalité du front intérieur comme de celle du champ de bataille pour ainsi proposer une réinterprétation de cette victimisation si profondément ancrée dans le souvenir québécois.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Depuis les années 1990, les indicateurs de la santé sexuelle des jeunes de 18 à 25 ans démontrent que ce groupe d’âge est sexuellement vulnérable, ce qui est observable en raison de la hausse du taux d’infections transmises sexuellement, ainsi que des lacunes de connaissances en matière de santé sexuelle. Ce mémoire propose un regard nouveau sur la santé sexuelle des jeunes à partir d’un faisceau de perspectives sociologiques axées sur les déterminants sociaux de la santé pour mieux comprendre la vulnérabilité sexuelle chez les jeunes. Nous faisons appel à trois pistes analytiques en particulier : la perspective matérialiste, la perspective bio-psycho-sociale et la perspective des parcours de vie. Notre démarche de recherche s’inscrit dans une approche issue de la théorisation ancrée, employée au sein d’une clinique jeunesse de Montréal. Nos outils d’investigation consistent en entretiens semi-dirigés réalisés avec des intervenantes de la clinique et des jeunes patients âgés de 18 à 25 ans, ainsi qu’en observations non participantes dans divers lieux de la clinique. Les résultats de cette recherche font ressortir quatre déterminants sociaux : la question des connaissances en matière de santé sexuelle, les scripts sexuels genrés, la période de la jeunesse lors du parcours sexuel et les caractéristiques du quartier du centre-ville de Montréal. En tenant compte des perspectives croisées de ceux qui voient (les intervenantes) et de ceux qui vivent (les jeunes) la vulnérabilité sexuelle, nous pouvons mieux définir ces déterminants, leurs sources et leurs effets. Nous faisons également état de nos résultats au prisme des trois cadres analytiques des déterminants sociaux de la santé. Nous espérons que ces résultats inciteront la poursuite de recherches dans le domaine des déterminants sociaux de la vulnérabilité sexuelle et qu’ils seront utiles dans la formulation des recommandations pratiques pour les interventions en santé sexuelle auprès des jeunes.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

By employing interpretive policy analysis this thesis aims to assess, measure, and explain policy capacity for government and non-government organizations involved in reclaiming Alberta's oil sands. Using this type of analysis to assess policy capacity is a novel approach for understanding reclamation policy; and therefore, this research will provide a unique contribution to the literature surrounding reclamation policy. The oil sands region in northeast Alberta, Canada is an area of interest for a few reasons; primarily because of the vast reserves of bitumen and the environmental cost associated with developing this resource. An increase in global oil demand has established incentive for industry to seek out and develop new reserves. Alberta's oil sands are one of the largest remaining reserves in the world, and there is significant interest in increasing production in this region. Furthermore, tensions in several oil exporting nations in the Middle East remain unresolved, and this has garnered additional support for a supply side solution to North American oil demands. This solution relies upon the development of reserves in both the United States and Canada. These compounding factors have contributed to the increased development in the oil sands of northeastern Alberta. Essentially, a rapid expansion of oil sands operations is ongoing, and is the source of significant disturbance across the region. This disturbance, and the promises of reclamation, is a source of contentious debates amongst stakeholders and continues to be highly visible in the media. If oil sands operations are to retain their social license to operate, it is critical that reclamation efforts be effective. One concern non-governmental organizations (NGOs) expressed criticizes the current monitoring and enforcement of regulatory programs in the oil sands. Alberta's NGOs have suggested the data made available to them originates from industrial sources, and is generally unchecked by government. In an effort to discern the overall status of reclamation in the oil sands this study explores several factors essential to policy capacity: work environment, training, employee attitudes, perceived capacity, policy tools, evidence based work, and networking. Data was collected through key informant interviews with senior policy professionals in government and non-government agencies in Alberta. The following are agencies of interest in this research: Canadian Association of Petroleum Producers (CAPP); Alberta Environment and Sustainable Resource Development (AESRD); Alberta Energy Regulator (AER); Cumulative Environmental Management Association (CEMA); Alberta Environment Monitoring, Evaluation, and Reporting Agency (AEMERA); Wood Buffalo Environmental Association (WBEA). The aim of this research is to explain how and why reclamation policy is conducted in Alberta's oil sands. This will illuminate government capacity, NGO capacity, and the interaction of these two agency typologies. In addition to answering research questions, another goal of this project is to show interpretive analysis of policy capacity can be used to measure and predict policy effectiveness. The oil sands of Alberta will be the focus of this project, however, future projects could focus on any government policy scenario utilizing evidence-based approaches.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Recently, the interest of the automotive market for hybrid vehicles has increased due to the more restrictive pollutants emissions legislation and to the necessity of decreasing the fossil fuel consumption, since such solution allows a consistent improvement of the vehicle global efficiency. The term hybridization regards the energy flow in the powertrain of a vehicle: a standard vehicle has, usually, only one energy source and one energy tank; instead, a hybrid vehicle has at least two energy sources. In most cases, the prime mover is an internal combustion engine (ICE) while the auxiliary energy source can be mechanical, electrical, pneumatic or hydraulic. It is expected from the control unit of a hybrid vehicle the use of the ICE in high efficiency working zones and to shut it down when it is more convenient, while using the EMG at partial loads and as a fast torque response during transients. However, the battery state of charge may represent a limitation for such a strategy. That’s the reason why, in most cases, energy management strategies are based on the State Of Charge, or SOC, control. Several studies have been conducted on this topic and many different approaches have been illustrated. The purpose of this dissertation is to develop an online (usable on-board) control strategy in which the operating modes are defined using an instantaneous optimization method that minimizes the equivalent fuel consumption of a hybrid electric vehicle. The equivalent fuel consumption is calculated by taking into account the total energy used by the hybrid powertrain during the propulsion phases. The first section presents the hybrid vehicles characteristics. The second chapter describes the global model, with a particular focus on the energy management strategies usable for the supervisory control of such a powertrain. The third chapter shows the performance of the implemented controller on a NEDC cycle compared with the one obtained with the original control strategy.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Human scent, or the volatile organic compounds (VOCs) produced by an individual, has been recognized as a biometric measurement because of the distinct variations in both the presence and abundance of these VOCs between individuals. In forensic science, human scent has been used as a form of associative evidence by linking a suspect to a scene/object through the use of human scent discriminating canines. The scent most often collected and used with these specially trained canines is from the hands because a majority of the evidence collected is likely to have been handled by the suspect. However, the scents from other biological specimens, especially those that are likely to be present at scenes of violent crimes, have yet to be explored. Hair, fingernails and saliva are examples of these types of specimens. In this work, a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the identification of VOCs from hand odor, hair, fingernails and saliva. Sixty individuals were sampled and the profiles of the extracted VOCs were evaluated to assess whether they could be used for distinguishing individuals. Preliminary analysis of the biological specimens collected from an individual (intra-subject) showed that, though these materials have some VOCs in common, their overall chemical profile is different for each specimen type. Pair-wise comparisons, using Spearman Rank correlations, were made between the chemical profiles obtained from each subject, per a specimen type. Greater than 98.8% of the collected samples were distinguished from the subjects for all of the specimen types, demonstrating that these specimens can be used for distinguishing individuals. Additionally, field trials were performed to determine the utility of these specimens as scent sources for human scent discriminating canines. Three trials were conducted to evaluate hair, fingernails and saliva in comparison to hand odor, which was considered the standard source of human odor. It was revealed that canines perform similarly to these alternative human scent sources as they do to hand odor implying that, though there are differences in the chemical profiles released by these specimens, they can still be used for the discrimination of individuals by trained canines.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This research study was designed to examine the relationship between globalization as measured by the KOF index, its related forces (economic, political, cultural and technological) and the public provision of higher education. This study is important since globalization is increasingly being associated with changes in critical aspects of higher education. The public provision of education was measured by government expenditure and educational outcomes; that is participation, gender equity and attainment. The study utilized a non-experimental quantitative research design. Data collected from secondary sources for 139 selected countries was analyzed. The countries were geographically distributed and included both developed and developing countries. The choice of countries for inclusion in the study was based on data availability. The data, which was sourced from international organizations such as the United Nations and the World Bank, were examined for different time periods using five year averages. The period covered was 1970 to 2009. The relationship between globalization and the higher education variables was examined using cross sectional regression analysis while controlling for economic, political and demographic factors. The major findings of the study are as follows. For the two spending models, only one revealed a significant relationship between globalization and education with the R2 s ranging from .222 to .448 over the period. This relationship was however negative indicating that as globalization increased, spending on higher education declined. However, for the education outcomes models, this relationship was not significant. For the sub-indices of globalization, only the political dimension showed significance as shown in the spending model. Political globalization was significant for six periods with R2 s ranging from .31 to .52. The study concluded that the results are mixed for both the spending and outcome models. It also found no robust effects of globalization on government education provision. This finding is not surprising given the existing literature which sees mixed results on the social impact of globalization.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The purpose of this study was to determine whether there was a relationship between pressure to perform on state mandated, high-stakes tests and the rate of student escape behavior defined as the number of school suspensions and absences. The state assigned grade of a school was used as a surrogate measure of pressure with the assumption that pressure increased as the school grade decreased. Student attendance and suspension data were gathered from all 33 of the regular public high schools in Miami-Dade County Public Schools. The research questions were: Is the number of suspensions highest in the third quarter, when most FCAT preparation takes place for each of the 3 school years 2007-08 through 2009-10? How accurately does the high school’s grade predict the number of suspensions and number of absences during each of the 4 school years 2005-06 through 2008-09? The research questions were answered using repeated measures analysis of variance for research question #1 and non-linear multiple regression for research question #2. No significant difference could be found between the numbers of suspensions in each of the grading periods nor was there a relationship between the number of suspensions and school grade. A statistically significant relationship was found between student attendance and school grade. When plotted, this relationship was found to be quadratic in nature and formed a loose inverted U for each of the four years during which data were collected. This indicated that students in very high and very low performing schools had low levels of absences while those in the midlevel of the distribution of school performance (C schools) had the greatest rates of absence. Identifying a relationship between the pressures associated with high stakes testing and student escape behavior suggests that it might be useful for building administrators to reevaluate test preparation activities and procedures being used in their building and to include anxiety reducing strategies. As a relationship was found, it sets the foundation for future studies to identify whether testing related activities are impacting some students emotionally and are causing unintended consequences of testing mandates.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Routine monitoring of environmental pollution demands simplicity and speed without sacrificing sensitivity or accuracy. The development and application of sensitive, fast and easy to implement analytical methodologies for detecting emerging and traditional water and airborne contaminants in South Florida is presented. A novel method was developed for quantification of the herbicide glyphosate based on lyophilization followed by derivatization and simultaneous detection by fluorescence and mass spectrometry. Samples were analyzed from water canals that will hydrate estuarine wetlands of Biscayne National Park, detecting inputs of glyphosate from both aquatic usage and agricultural runoff from farms. A second study describes a set of fast, automated LC-MS/MS protocols for the analysis of dioctyl sulfosuccinate (DOSS) and 2-butoxyethanol, two components of Corexit®. Around 1.8 million gallons of those dispersant formulations were used in the response efforts for the Gulf of Mexico oil spill in 2010. The methods presented here allow the trace-level detection of these compounds in seawater, crude oil and commercial dispersants formulations. In addition, two methodologies were developed for the analysis of well-known pollutants, namely Polycyclic Aromatic Hydrocarbons (PAHs) and airborne particulate matter (APM). PAHs are ubiquitous environmental contaminants and some are potent carcinogens. Traditional GC-MS analysis is labor-intensive and consumes large amounts of toxic solvents. My study provides an alternative automated SPE-LC-APPI-MS/MS analysis with minimal sample preparation and a lower solvent consumption. The system can inject, extract, clean, separate and detect 28 PAHs and 15 families of alkylated PAHs in 28 minutes. The methodology was tested with environmental samples from Miami. Airborne Particulate Matter is a mixture of particles of chemical and biological origin. Assessment of its elemental composition is critical for the protection of sensitive ecosystems and public health. The APM collected from Port Everglades between 2005 and 2010 was analyzed by ICP-MS after acid digestion of filters. The most abundant elements were Fe and Al, followed by Cu, V and Zn. Enrichment factors show that hazardous elements (Cd, Pb, As, Co, Ni and Cr) are introduced by anthropogenic activities. Data suggest that the major sources of APM were an electricity plant, road dust, industrial emissions and marine vessels.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We study the changes in the consumers’ and producers’ surplus associated with acquisition deals where there is a non-competition covenant that forbids the seller from re-entering the market over a given time period. We find that these cquisition deals can lead to significant negative (positive) changes in the producers’ consumers’) surplus, which decrease significantly with the time period of the covenant. We also show that the effect of the time period of the covenant on the welfare change can be positive or negative. It depends largely on the market conditions, such as the profit uncertainty and growth rate.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

BACKGROUND Despite great effort and investment incurred over decades to control bovine tuberculosis (bTB), it is still one of the most important zoonotic diseases in many areas of the world. Test-and-slaughter strategies, the basis of most bTB eradication programs carried out worldwide, have demonstrated its usefulness in the control of the disease. However, in certain countries, eradication has not been achieved due in part to limitations of currently available diagnostic tests. In this study, results of in-vivo and post-mortem diagnostic tests performed on 3,614 animals from 152 bTB-infected cattle herds (beef, dairy, and bullfighting) detected in 2007-2010 in the region of Castilla y León, Spain, were analyzed to identify factors associated with positive bacteriological results in cattle that were non-reactors to the single intradermal tuberculin test, to the interferon-gamma (IFN-γ) assay, or to both tests applied in parallel (Test negative/Culture + animals, T-/C+). The association of individual factors (age, productive type, and number of herd-tests performed since the disclosure of the outbreak) with the bacteriology outcome (positive/negative) was analyzed using a mixed multivariate logistic regression model. RESULTS The proportion of non-reactors with a positive post-mortem result ranged from 24.3% in the case of the SIT test to 12.9% (IFN-γ with 0.05 threshold) and 11.9% (95% CI 9.9-11.4%) using both tests in parallel. Older (>4.5 years) and bullfighting cattle were associated with increased odds of confirmed bTB infection by bacteriology, whereas dairy cattle showed a significantly lower risk. Ancillary use of IFN-γ assay reduced the proportion of T-/C + animals in high risk groups. CONCLUSIONS These results demonstrate the likelihood of positive bacteriological results in non-reactor cattle is influenced by individual epidemiological factors of tested animals. Increased surveillance on non-reactors with an increased probability of being false negative could be helpful to avoid bTB persistence, particularly in chronically infected herds. These findings may aid in the development of effective strategies for eradication of bTB in Spain.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Au Québec, la mémoire de la Grande Guerre renvoie automatiquement à une vision douloureuse de l’événement. Créée et alimentée par des souvenirs à forte charge émotive tels la crise de la conscription, les émeutes de Pâques et l’inhospitalité de l’Armée canadienne envers les combattants canadiens-français, cette mémoire est non seulement négative, mais également victimisante. Dans leur récit du conflit, les Québécois ont pris pour vérité une version qui les dépeint comme boucs émissaires des Canadiens anglais. Acceptée et intégrée autant dans l’historiographie que dans la croyance collective, cette thèse du Canadien français opprimé n’a jamais été questionnée. Ce mémoire entend donc revisiter cette version en la confrontant aux sources laissées par les contemporains. En utilisant la presse anglophone et les témoignages de combattants, il lève le voile sur le regard anglo-saxon envers les Canadiens français et dans une plus large mesure, sur les relations interethniques pendant la guerre. Il témoigne de la réalité du front intérieur comme de celle du champ de bataille pour ainsi proposer une réinterprétation de cette victimisation si profondément ancrée dans le souvenir québécois.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Depuis les années 1990, les indicateurs de la santé sexuelle des jeunes de 18 à 25 ans démontrent que ce groupe d’âge est sexuellement vulnérable, ce qui est observable en raison de la hausse du taux d’infections transmises sexuellement, ainsi que des lacunes de connaissances en matière de santé sexuelle. Ce mémoire propose un regard nouveau sur la santé sexuelle des jeunes à partir d’un faisceau de perspectives sociologiques axées sur les déterminants sociaux de la santé pour mieux comprendre la vulnérabilité sexuelle chez les jeunes. Nous faisons appel à trois pistes analytiques en particulier : la perspective matérialiste, la perspective bio-psycho-sociale et la perspective des parcours de vie. Notre démarche de recherche s’inscrit dans une approche issue de la théorisation ancrée, employée au sein d’une clinique jeunesse de Montréal. Nos outils d’investigation consistent en entretiens semi-dirigés réalisés avec des intervenantes de la clinique et des jeunes patients âgés de 18 à 25 ans, ainsi qu’en observations non participantes dans divers lieux de la clinique. Les résultats de cette recherche font ressortir quatre déterminants sociaux : la question des connaissances en matière de santé sexuelle, les scripts sexuels genrés, la période de la jeunesse lors du parcours sexuel et les caractéristiques du quartier du centre-ville de Montréal. En tenant compte des perspectives croisées de ceux qui voient (les intervenantes) et de ceux qui vivent (les jeunes) la vulnérabilité sexuelle, nous pouvons mieux définir ces déterminants, leurs sources et leurs effets. Nous faisons également état de nos résultats au prisme des trois cadres analytiques des déterminants sociaux de la santé. Nous espérons que ces résultats inciteront la poursuite de recherches dans le domaine des déterminants sociaux de la vulnérabilité sexuelle et qu’ils seront utiles dans la formulation des recommandations pratiques pour les interventions en santé sexuelle auprès des jeunes.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dietary fibre (DF) has been recognized as a major determinant for improvement of health. Hence the means of information through which people become aware of its benefits are crucial. This work aimed at studying the sources of information about DF, as a means to educate people about aspects related to healthy eating. Factors such as gender, level of education, living environment or country were evaluated as to their effect on the selection of sources and preferences. For this, a descriptive cross-sectional study by means of a questionnaire, applied to a non-probabilistic sample of 6010 participants from 10 countries in different continents (Europe, Africa and America), answered after informed consent by all participants. For the analysis were used several descriptive statistics tools, crosstabs and chi square test to assess the relations between some of the variables under study. The results showed that mostly the information about DF comes from the internet, but the participants recognize that television might be a most suitable way to disseminate information about DF. The results also indicated differences between genders, levels of education, living environments and countries. The internet, the preferred source of information, got highest scores for Hungary, for urban areas, for university level of education and for female gender. The radio, the least scored source of information, was preferred in Egypt, for men and with lower education (primary school). As a conclusion, people get information through the internet due to easy access. However, it is to some extent a risk given the impossibility to control de information made public on the internet. The role of health centers and hospitals as well as schools should definitely be increased, as a responsible way to ensure correct information.