929 resultados para Risky sleepy driving
Resumo:
Previous studies addressing the importance of host gender in parasite transmission have shed light on males as the more important hosts, with the higher transmission potential of males being explained by the fact that they often harbour higher parasite loads than females. However, in some systems females are more heavily infected than males and may be responsible for driving infection under such circumstances. Using a wild population of common voles (Microtus arvalis), we showed that females were more frequently infected by the intestinal nematode Trichuris arvicolae than males (i.e. prevalence based on the presence of eggs in the faeces) and that females were shedding greater numbers of parasite eggs per gram of faeces (EPG) than males. By applying an anthelmintic treatment to either male or female voles, we demonstrated that treating females significantly reduced parasite burdens (i.e. prevalence and EPG) of both male and female hosts, while treating males only reduced parasite burden in males. These findings indicate that in this female-biased infection system females play a more important role than males in driving the dynamics of parasite transmission.
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Per definition, alcohol expectancies (after alcohol I expect X), and drinking motives (I drink to achieve X) are conceptually distinct constructs. Theorists have argued that motives mediate the association between expectancies and drinking outcomes. Yet, given the use of different instruments, do these constructs remain distinct when assessment items are matched? The present study tested to what extent motives mediated the link between expectancies and alcohol outcomes when identical items were used, first as expectancies and then as motives. A linear structural equation model was estimated based on a national representative sample of 5,779 alcohol-using students in Switzerland (mean age = 15.2 years). The results showed that expectancies explained up to 38% of the variance in motives. Together with motives, they explained up to 48% of the variance in alcohol outcomes (volume, 5+ drinking, and problems). In 10 of 12 outcomes, there was a significant mediated effect that was often higher than the direct expectancy effect. For coping, the expectancy effect was close to zero, indicating the strongest form of mediation. In only one case (conformity and 5+ drinking), there was a direct expectancy effect but no mediation. To conclude, the study demonstrates that motives are distinct from expectancies even when identical items are used. Motives are more proximally related to different alcohol outcomes, often mediating the effects of expectancies. Consequently, the effectiveness of interventions, particularly those aimed at coping drinkers, should be improved through a shift in focus from expectancies to drinking motives.
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Els programes formatius de seguretat viària són una mesura que s’aplica des de l’execució penal a la comunitat en delictes de trànsit i tenen com a finalitat reduir la reincidència dels conductors de major risc. L’objectiu principal del treball és identificar les característiques comunes dels infractors de trànsit que fan aquest tipus d’intervenció, conèixer els factors de risc associats a aquests infractors i en quina mesura l’estat psicològic és un factor de risc en l’estil de conducció. També es volia determinar si hi havia diferències entre les entitats que impartien la formació i avaluar l’efectivitat d’aquests programes en l’estil de conducció dels participants en finalitzar el curs. En l’estudi, hi van participar 278 voluntaris del total de 354 infractors de trànsit que van fer el programa formatiu entre l’1 d’abril de 2009 i el 13 de febrer de 2010. How do we drive after a driving educational program? The study analyzes the results of educational programs that are applied as a community sanction for those convicted for driving offenses, in majority drunk driving, in Catalonia. Between April 1, 2009 and February 13, 2010 a total of 278 offenders participated in these mandatory educational programs. ¿Cómo conducimos después de un programa formativo de educación vial? El estudio analiza los resultados de los programas formativos que se aplican como medida penal alternativa a la prisión a los condenados por delitos de tráfico en Cataluña. En total han participado 278 infractores que realizaron el programa formativo entre el 1 de abril de 2009 y el 13 de febrero de 2010.
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It is generally accepted that most plant populations are locally adapted. Yet, understanding how environmental forces give rise to adaptive genetic variation is a challenge in conservation genetics and crucial to the preservation of species under rapidly changing climatic conditions. Environmental variation, phylogeographic history, and population demographic processes all contribute to spatially structured genetic variation, however few current models attempt to separate these confounding effects. To illustrate the benefits of using a spatially-explicit model for identifying potentially adaptive loci, we compared outlier locus detection methods with a recently-developed landscape genetic approach. We analyzed 157 loci from samples of the alpine herb Gentiana nivalis collected across the European Alps. Principle coordinates of neighbor matrices (PCNM), eigenvectors that quantify multi-scale spatial variation present in a data set, were incorporated into a landscape genetic approach relating AFLP frequencies with 23 environmental variables. Four major findings emerged. 1) Fifteen loci were significantly correlated with at least one predictor variable (R (adj) (2) > 0.5). 2) Models including PCNM variables identified eight more potentially adaptive loci than models run without spatial variables. 3) When compared to outlier detection methods, the landscape genetic approach detected four of the same loci plus 11 additional loci. 4) Temperature, precipitation, and solar radiation were the three major environmental factors driving potentially adaptive genetic variation in G. nivalis. Techniques presented in this paper offer an efficient method for identifying potentially adaptive genetic variation and associated environmental forces of selection, providing an important step forward for the conservation of non-model species under global change.
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ABSTRACT : Gene duplication is a fundamental source of raw material for the origin of genetic novelty. It has been assumed for a long time that DNA-based gene duplication was the only source of new genes. Recently however, RNA-based gene duplication (retroposition) was shown in multiple organisms to contribute significantly to their genetic diversity. This mechanism produces intronless gene copies (retrocopies) that are inserted in random genomic position, independent of the position of the parental source genes. In human, mouse and fruit fly, it was demonstrated that the X-linked genes spawned an excess of functional retroposed gene copies (retrogenes). In human and mouse, the X chromosome also recruited an excess of retrogenes. Here we further characterized these interesting biases related to the X chromosome in mammals. Firstly, we have confirmed presence of the aforementioned biases in dog and opossum genome. Then based on the expression profile of retrogenes during various spermatogenetic stages, we have provided solid evidence that meiotic sex chromosome inactivation (MSCI) is responsible for an excess of retrogenes stemming from the X chromosome. Moreover, we showed that the X-linked genes started to export an excess of retrogenes just after the split of eutherian and marsupial mammalian lineages. This suggests that MSCI has originated around this time as well. More fundamentally, as MSCI reflects the spread of recombination barrier between the X and Y chromosomes during their evolution, our observation allowed us to re-estimate the age of mammalian sex chromosomes. Previous estimates suggested that they emerged in the common ancestor of all mammals (before the split of monotreme lineage); whereas, here we showed that they originated around the split of marsupial and eutherian lineages, after the divergence of monotremes. Thus, the therian (marsupial and eutherian) sex chromosomes are younger than previously thought. Thereafter, we have characterized the bias related to the recruitment of genes to the X chromosome. Sexually antagonistic forces are most likely driving this pattern. Using our limited retrogenes expression data, it is difficult to determine the exact nature of these forces but some conclusions have been made. Lastly, we looked at the history of this biased recruitment: it commenced around the split of marsupial and eutherian lineages (akin to the biased export of genes out of the X). In fact, the sexually antagonistic forces are predicted to appear just around that time as well. Thereby, the history of the recruitment of genes to the X, provides an indirect evidence that these forces are responsible for this bias.
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Estudi de la presència de cocaïna i opiacis en saliva, en subjectes sospitosos de conduir sota els efectes de les drogues. Aplicació d’un test d’immunoassaig (Cozart). Confirmació i quantificació dels resultats positius (CG-EM). Comparació amb alteracions clíniques en els subjectes. No hi ha diferències entre concentracions de droga i signes clínics avaluades
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Adorno es un referente en la disciplina musicológica. Convencido de que el hombre a través de la dialéctica materialista podía entender el mundo y cambiarlo, consideraba que el arte no debía ser mero exponente de la sociedad, sino fermento de ese cambio. La sociedad debía transformarse a sí misma desde ella misma, y el arte, producto de la sociedad, era un medio para ello. Ante el fenómeno fetichista de la sociedad industrializada, éste debía presentarse como antítesis de la misma, siendo la única vía posible para la conservación de su carácter de verdad el aislamiento. En el ámbito musical fue Schönberg quien se mostró distante al público de su tiempo a través de una música antagónica y disonante que reflejaba el momento de horror, angustia y barbarie del hombre contemporáneo.
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A recent report by the Centre for Ageing Research and Development in Ireland (CARDI) entitled Illustrating Ageing in Ireland, North and South found that since the 1920s the number of years males can expect to live rose by about 20 years while the number of years females can expect to live rose by about 24-25 years. It is not clear, however, if these years of life gained are lived in good health.While there is considerable policy focus on reducing inequalities in life expectancy, much less is known about the variation in health expectancy that exists across the island of Ireland. The debate hinges on our understanding of what is driving the changes in life expectancy, healthy life expectancy and the gap between the two.IPH in association with CARDI, hosted a Health Analysts' Special Interest Group (HASIG) seminar discussing the policy implications of this debate. The seminar introduced the range of health expectancy measures and compared them to life expectancy. Initial findings from the all-island study of life expectancy and healthy life expectancy were also presented.
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High-growth firms have been shown to be a key factor for economic growth and structural change. This paper analyses the determinants of the number of high-growth firms in a country for 17 OECD countries between 1999 and 2005, using the Amadeus data set, the GEM data set, and others. The first contribution of this paper is that it is – as far as we know – the first empirical analysis of high-growth firms at the country level on the basis of actual measured growth. Second, we find indicative empirical evidence for three driving forces of high growth, viz. entrepreneurship, institutional settings, and opportunities for growth, all in accordance with theory and empirical findings in related fields of research. Third, the paper gives a tentative explanation of the differences in the average percentage of high-growth firms between countries. Finally, the paper gives some clues for policy makers how to promote high-growth firms. Keywords: high-growth firms, fast growing firms, entrepreneurship, institutional obstacles, opportunities for growth
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This article studies how product introduction decisions relate to profitability and uncertainty in the context of multi-product firms and product differentiation. These two features, common to many modern industries, have not received much attention in the literature as compared to the classical problem of firm entry, even if the determinants of firm and product entry are quite different. The theoretical predictions about the sign of the impact of uncertainty on product entry are not conclusive. Therefore, an econometric model relating firms’ product introduction decisions with profitability and profit uncertainty is proposed. Firm’s estimated profits are obtained from a structural model of product demand and supply, and uncertainty is proxied by profits’ variance. The empirical analysis is carried out using data on the Spanish car industry for the period 1990-2000. The results show a positive relationship between product introduction and profitability, and a negative one with respect to profit variability. Interestingly, the degree of uncertainty appears to be a driving force of entry stronger than profitability, suggesting that the product proliferation process in the Spanish car market may have been mainly a consequence of lower uncertainty rather than the result of having a more profitable market. Keywords: Product introduction, entry, uncertainty, multiproduct firms, automobile JEL codes: L11, L13
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PURPOSE: To examine the associations between substance use and other health-risk behaviors and quality of life (QOL) among young men. METHODS: The analytical sample consisted of 5,306 young Swiss men who participated in the Cohort Study on Substance Use Risk Factors. Associations between seven distinct self-reported health-risk behaviors (risky single-occasion drinking; volume drinking; cigarette smoking; cannabis use; use of any other illicit drugs; sexual intercourse without a condom; low physical activity) were assessed via chi-square analysis. Logistic regression analyses were conducted to study the associations between each particular health-risk behavior and either physical or mental QOL (assessed with the SF-12v2) while adjusting for socio-demographic variables and the presence of all other health-risk behaviors. RESULTS: Most health-risk behaviors co-occurred. However, low physical activity was not or negatively related to other health-risk behaviors. Almost all health-risk behaviors were associated with a greater likelihood of compromised QOL. However, sexual intercourse without a condom (not associated with both physical and mental QOL) and frequent risky single-occasion drinking (not related to mental QOL after adjusting for the presence of other health-risk behaviors; positively associated with physical QOL) differed from this pattern. CONCLUSIONS: Health-risk behaviors are mostly associated with compromised QOL. However, sexual intercourse without a condom and frequent risky single-occasion drinking differ from this pattern and are therefore possibly particularly difficult to change relative to other health-risk behaviors.
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PURPOSE OF REVIEW: The purpose of this review was to summarize available data on uveal melanoma biology and treatment in order to provide the medical community with a basic reference that would help to make further progress in this rare disease, which remains difficult to treat.¦RECENT FINDINGS: The most relevant recent findings driving current clinical developments are in the elucidation of uveal melanoma genetics and genomics. The key driving mutations - that differ completely from cutaneous melanoma - have been identified. Based on the novel insights into key signaling pathways, the first clinical trials with targeted treatments have been implemented. However, systemic and regional chemotherapy approaches as well as other regional treatment modalities for liver metastases are also a major part of the current treatment armamentarium and are prospectively being evaluated.¦SUMMARY: In summary, the recent biological findings and the creation of a series of clinical trials underscore how the international community is able to perform relevant advances in an extremely rare disease.
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Whole genome sequences of microbial pathogens present new opportunities for clinical application. Presently, genome sequencing of the human protozoan parasite Leishmania major is in progress. The driving forces behind the genome project are to identify genes with key cellular functions and new drug targets, to increase knowledge on mechanisms of drug resistance and to favor technology transfer to scientists from endemic countries. Sequencing of the genome is also aimed at the identification of genes that are expressed in the infectious stages of the parasite and in particular in the intracellular form of the parasite. Several protective antigens of Leishmania have been identified. In addition to these antigens, lysosomal cysteine proteinases (CPs) have been characterized in different strains of Leishmania and Trypanosoma, as new target molecules. Recently, we have isolated and characterized Type I (CPB) and Type II (CPA) cysteine proteinase encoding genes from L. major. The exact function of cysteine proteinases of Leishmania is not completely understood, although there are a few reports describing their role as virulence factors. One specific feature of CPB in Leishmania and other trypanosomatids, is the presence of a Cterminal extension (CTE) which is possibly indicative of conserved structure and function. Recently, we demonstrated that DNA immunization of genetically susceptible BALB / c mice, using a cocktail of CPB and CPA genes, induced long lasting protection against L. major infection. This review intends to give an overview of the current knowledge on genetic vaccination used against leishmaniasis and the importance of CP genes for such an approach.
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This thesis focuses on theoretical asset pricing models and their empirical applications. I aim to investigate the following noteworthy problems: i) if the relationship between asset prices and investors' propensities to gamble and to fear disaster is time varying, ii) if the conflicting evidence for the firm and market level skewness can be explained by downside risk, Hi) if costly learning drives liquidity risk. Moreover, empirical tests support the above assumptions and provide novel findings in asset pricing, investment decisions, and firms' funding liquidity. The first chapter considers a partial equilibrium model where investors have heterogeneous propensities to gamble and fear disaster. Skewness preference represents the desire to gamble, while kurtosis aversion represents fear of extreme returns. Using US data from 1988 to 2012, my model demonstrates that in bad times, risk aversion is higher, more people fear disaster, and fewer people gamble, in contrast to good times. This leads to a new empirical finding: gambling preference has a greater impact on asset prices during market downturns than during booms. The second chapter consists of two essays. The first essay introduces a foramula based on conditional CAPM for decomposing the market skewness. We find that the major market upward and downward movements can be well preadicted by the asymmetric comovement of betas, which is characterized by an indicator called "Systematic Downside Risk" (SDR). We find that SDR can efafectively forecast future stock market movements and we obtain out-of-sample R-squares (compared with a strategy using historical mean) of more than 2.27% with monthly data. The second essay reconciles a well-known empirical fact: aggregating positively skewed firm returns leads to negatively skewed market return. We reconcile this fact through firms' greater response to negative maraket news than positive market news. We also propose several market return predictors, such as downside idiosyncratic skewness. The third chapter studies the funding liquidity risk based on a general equialibrium model which features two agents: one entrepreneur and one external investor. Only the investor needs to acquire information to estimate the unobservable fundamentals driving the economic outputs. The novelty is that information acquisition is more costly in bad times than in good times, i.e. counter-cyclical information cost, as supported by previous empirical evidence. Later we show that liquidity risks are principally driven by costly learning. Résumé Cette thèse présente des modèles théoriques dévaluation des actifs et leurs applications empiriques. Mon objectif est d'étudier les problèmes suivants: la relation entre l'évaluation des actifs et les tendances des investisseurs à parier et à crainadre le désastre varie selon le temps ; les indications contraires pour l'entreprise et l'asymétrie des niveaux de marché peuvent être expliquées par les risques de perte en cas de baisse; l'apprentissage coûteux augmente le risque de liquidité. En outre, des tests empiriques confirment les suppositions ci-dessus et fournissent de nouvelles découvertes en ce qui concerne l'évaluation des actifs, les décisions relatives aux investissements et la liquidité de financement des entreprises. Le premier chapitre examine un modèle d'équilibre où les investisseurs ont des tendances hétérogènes à parier et à craindre le désastre. La préférence asymétrique représente le désir de parier, alors que le kurtosis d'aversion représente la crainte du désastre. En utilisant les données des Etats-Unis de 1988 à 2012, mon modèle démontre que dans les mauvaises périodes, l'aversion du risque est plus grande, plus de gens craignent le désastre et moins de gens parient, conatrairement aux bonnes périodes. Ceci mène à une nouvelle découverte empirique: la préférence relative au pari a un plus grand impact sur les évaluations des actifs durant les ralentissements de marché que durant les booms économiques. Exploitant uniquement cette relation générera un revenu excédentaire annuel de 7,74% qui n'est pas expliqué par les modèles factoriels populaires. Le second chapitre comprend deux essais. Le premier essai introduit une foramule base sur le CAPM conditionnel pour décomposer l'asymétrie du marché. Nous avons découvert que les mouvements de hausses et de baisses majeures du marché peuvent être prédits par les mouvements communs des bêtas. Un inadicateur appelé Systematic Downside Risk, SDR (risque de ralentissement systématique) est créé pour caractériser cette asymétrie dans les mouvements communs des bêtas. Nous avons découvert que le risque de ralentissement systématique peut prévoir les prochains mouvements des marchés boursiers de manière efficace, et nous obtenons des carrés R hors échantillon (comparés avec une stratégie utilisant des moyens historiques) de plus de 2,272% avec des données mensuelles. Un investisseur qui évalue le marché en utilisant le risque de ralentissement systématique aurait obtenu une forte hausse du ratio de 0,206. Le second essai fait cadrer un fait empirique bien connu dans l'asymétrie des niveaux de march et d'entreprise, le total des revenus des entreprises positiveament asymétriques conduit à un revenu de marché négativement asymétrique. Nous décomposons l'asymétrie des revenus du marché au niveau de l'entreprise et faisons cadrer ce fait par une plus grande réaction des entreprises aux nouvelles négatives du marché qu'aux nouvelles positives du marché. Cette décomposition révélé plusieurs variables de revenus de marché efficaces tels que l'asymétrie caractéristique pondérée par la volatilité ainsi que l'asymétrie caractéristique de ralentissement. Le troisième chapitre fournit une nouvelle base théorique pour les problèmes de liquidité qui varient selon le temps au sein d'un environnement de marché incomplet. Nous proposons un modèle d'équilibre général avec deux agents: un entrepreneur et un investisseur externe. Seul l'investisseur a besoin de connaitre le véritable état de l'entreprise, par conséquent, les informations de paiement coutent de l'argent. La nouveauté est que l'acquisition de l'information coute plus cher durant les mauvaises périodes que durant les bonnes périodes, comme cela a été confirmé par de précédentes expériences. Lorsque la récession comamence, l'apprentissage coûteux fait augmenter les primes de liquidité causant un problème d'évaporation de liquidité, comme cela a été aussi confirmé par de précédentes expériences.