TEMPOS: A Platform for Developing Temporal Applications on Top of Object DBMS

This paper presents TEMPOS: a set of models and languages supporting the manipulation of temporal data on top of object DBMS. The proposed models exploit object-oriented technology to meet some important, yet traditionally neglected design criteria related to legacy code migration and representation independence. Two complementary ways for accessing temporal data are offered: a query language and a visual browser. The query language, namely TempOQL, is an extension of OQL supporting the manipulation of histories regardless of their representations, through fully composable functional operators. The visual browser offers operators that facilitate several time-related interactive navigation tasks, such as studying a snapshot of a collection of objects at a given instant, or detecting and examining changes within temporal attributes and relationships. TEMPOS models and languages have been formalized both at the syntactical and the semantical level and have been implemented on top of an object DBMS. The suitability of the proposals with regard to applications' requirements has been validated through concrete case studies

Antimicrobial activity of CPC and ASC against foodborne pathogens and the physiological effect on fresh-cut cantaloupe cubes at refrigerator temperatures

In the last few decades, fresh-cut fruit products have gained popularity with consumers. They require little to no further processing prior to consumption. Fresh-cut products also make fruits and vegetables more conveniently available to consumers year-round. There are limitations, however, to fresh-cut fruit and vegetables in the marketplace. These products are very perishable and could become contaminated with foodborne pathogens. Most fresh-cut fruits and vegetables will only last a short period of time at refrigerator temperatures. There are many possible routes of bacterial contamination in the fresh-cut produce industry. There is a need for antimicrobial compounds that can be applied to fruits and vegetables to help maintain the shelf-life of these products without greatly altering their sensory qualities. Cetylpyridinium chloride (CPC) and acidified sodium chlorite (ASC) have both been shown to have antimicrobial effects. This study was conducted to determine if cetylpyridinium chloride and acidified sodium chlorite would be effective in reducing E. coli 0157:H7, Salmonella Montevideo, and Shigella sonnei on the surface of inoculated and stored fresh-cut cantaloupe cubes. The effect of these compounds on the physiological quality of fresh-cut cantaloupe cubes was also investigated. Results obtained from this study show that both compounds were effective in significantly reducing the three pathogens. Significant reductions were achieved during both a preliminary 24 hour storage study and a 12 day shelf life study for all three pathogens. The 1.00% CPC and 1000 ppm ASC concentrations were most effective at reducing the three pathogens. It was also determined that CPC and ASC did not greatly affect the physiological quality (°Brix, firmness, color) of fresh-cut cubes stored at refrigerator temperatures for up to fourteen days. Treatment of fresh-cut cantaloupe cubes with CPC caused significant interaction effects between treatment levels and sampling day on the recovery of several characteristic impact flavor and aroma compounds (CIFAC). Concentrations of ASC caused significantly higher levels of certain volatiles to be recovered over the 14 day study

Birth weight and long-term outcomes in a developing country

This paper analyzes the empirical relationship between endowment at birth and long-term outcomes. Birth weight has been shown to influence outcomes later in life, suggesting that in-utero shocks have long lasting consequences. However, traditional measures of human capital at birth (i.e. birth weight) are potentially measured with error and endogenous. We deal with such issues thanks to the use of a long panel of children born in 1983 in Cebu (Philippines) and interviewed repeatedly until 2005. Our contribution is threefold. First, we build a refined health endowment measure netted out from prenatal investments. Our results show that the usual estimate of birth weight exceeds by 50\% the true causal effect of birth weight on later outcomes. Second, initial endowments affect trajectories both through the human capital production function and parental investment. The effect of birth endowment fades out over time but remains until adulthood. The fading out is very limited for health outcomes but more pronounced for educational outcomes. Finally, we find that parents tend to reinforce initial health endowments, but the effect of this behavior has almost no effect on final outcomes

Repères pour l'évaluation éthique des activités de recherche exécutées par les étudiantes et étudiants du collégial dans le cadre d'un cours

Avec la collaboration de Michel Bergeron, consultant en éthique et conduite responsable de la recherche, et Emmanuelle Marceau, chargée de projet à l'ARC.Disponible en français dans EDUQ.info sous le titre "Repères pour l'évaluation éthique des activités de recherche exécutées par les étudiantes et étudiants du collégial dans le cadre d'un cours"

Chronic aortic regurgitation in rats

Objectives: Aortic regurgitation (AR) induces left ventricular (LV) eccentric hypertrophy in response to chronic volume overload. Patients suffering from this disease often remain asymptomatic for decades before progressive LV dysfunction develops silently. Because of this slow evolution, large clinical trials with long-term follow-up on subjects with chronic AR are hard to perform. To overcome this problem, animal models have been developed in the past but results were very heterogeneous. Methods: Helped by echocardiography, we refined a known technique to induce homogenous degrees of severe AR in Wistar-Kyoto rats. The effects on LV function without treatment and with nifedipine (25 mg/kg daily) (a drug currently recommended in humans with chronic AR) were evaluated by echocardiography. Results: Over 6 months, nontreated animals developed progressive LV dilatation and eccentric hypertrophy, characteristic of chronic LV volume overload. The animals also developed progressive LV systolic dysfunction, mimicking closely the evolution of the disease in humans. Abnormal filling parameters were also detected in the majority of animals. Systolic and diastolic abnormalities were prevented but only partially in the group treated with nifedipine. Conclusion: This model can be used to study chronic AR and LV dysfunction associated with the disease. Nifedipine seems to protect the LV against chronic volume overload but only partially. Treatment strategies currently used in humans deserve further investigation

Les enjeux politiques de la gouvernance environnementale : le cas de la gestion des eaux de surface à São Paulo

Dans un contexte où les changements climatiques se manifestent sous forme de phénomènes climatiques extrêmes tels que des sècheresses prolongées et des précipitations abondantes soudaines, la question de la texture des sols urbains et de la protection des sources d’eau fait l’objet de nouvelles préoccupations en matière de planification urbaine. Alors que la régulation et la filtration de l’eau de ruissèlement sont restreintes par l’imperméabilité des surfaces urbaines, plusieurs métropoles, dont São Paulo, peuvent se retrouver en situation de crises dues à l’indisponibilité de l’eau potable, aux inondations subites ou à la création d’îlots de chaleur. L’efficacité de la gouvernance environnementale appliquée à la gestion des eaux en milieu métropolitain devient donc primordiale. Par une étude de cas de la métropole de São Paulo, la présente recherche tente d’élucider les facteurs rendant possible l’atteinte d’un modèle de gouvernance environnementale métropolitain qui permettrait de maintenir les fonctions écosystémiques des bassins versants et de construire la résilience à la variabilité climatique. La stratégie d’enquête, basée sur l’analyse de documents scientifiques et gouvernementaux, l’observation participante et la tenue d’entretiens semi-dirigés, permit de soulever plusieurs obstacles à l'application des politiques publiques de protection des espaces verts et des sources d’eau. La carence de maîtrise de l’usage des sols, la priorisation des intérêts économiques, la sectorisation des instances gouvernementales et la faible intégration de la société civile au processus de prise de décision surgissent comme d’importants freins à la construction d’une gouvernance environnementale à São Paulo. La considération des savoirs scientifiques et locaux et la gestion du risque lié à la variabilité climatique sont marginalisées par la sphère politique. Ainsi, la présence d’une vaste législation environnementale, telle qu’en vigueur dans la métropole de São Paulo, ne signifie pas forcément une application des projets et des règlements sans faille.In a context where climate changes are manifested by extreme climatic events such as prolonged droughts and sudden abundant rainfall, the issue of urban soil texture and water protection is a new concern in urban planning. While the regulation and filtration of runoff water is restricted by the impermeability of urban surfaces, several cities, including São Paulo, may end up in crisis due to the unavailability of drinking water, floods or creation of heat islands. The effectiveness of environmental governance applied to water management in metropolitan areas therefore becomes paramount importance. Through a case study of the metropolis of São Paulo, this research attempts to elucidate the factors that make it possible to achieve a metropolitan environmental governance that would maintain watersheds ecosystem functions and build resilience to climate variability. The research strategy, based on the analysis of scientific and governmental documents, participant observation and semistructured interviews, shows several obstacles to the application of public policies for the protection of green spaces and water sources. The lack of control over land use, the prioritization of economic interests, the governmental sectoralization and the weak integration of civil society into the decision-making process appear as major obstacles to the construction of environmental governance in São Paulo. Scientific and local knowledges and climate risk management are marginalized by the political sphere. Thus, the presence of a vast environmental legislation, as in place in the metropolis of São Paulo, does not necessarily mean an unfailing application of projects and regulations

Three essays on political institutions and environmental governance

This dissertation analyzes how political competition and judicial institutions shape environmental governance in democratic societies. The three chapters frame environmental problems in several different ways. In the first chapter, environmental policy is framed as an ideologically contentious public good. In the second chapter, two conceptions are juxtaposed: the environment as just another policy domain subject to political haggling, or the environment as bringing about new fundamental commitments in society, prone to becoming constitutionalized through legal deliberation. In the third chapter, the dynamic properties of technological transitions toward more sustainable modes of production are emphasized. Different types of institutions are considered in the three chapters. The first two chapters examine how political and legal processes interact. They also consider the different ways in which they channel the inputs and wishes of civil society. Chapter one is a formal model of the institution of citizen suits – a prevalent institution in environmental governance – and its interaction with the legislature. It shows that the reshaping of laws by citizens and courts after their enactment by the legislature might improve the decision process of the legislature and the public good outcomes that ensue. Chapter two is an empirical analysis of the dynamics of environmental legal rules. It uses the network of citations to legal precedent to test whether the dynamic body of law governing the environment is driven by political shifts in power or follows a process that is autonomous from these shifts in power. The results suggest that environmental law is now constitutionalized – its main principles entrenched in democratic culture rather than subject to the ebb and flow of democratic turnover of power. Chapter three also considers the dynamic aspects of governance. It uses a computational model to examine how political parties with different ideological commitments towards renewable energy might strategically use the path-dependence of technological transitions to shape policy over the long-term. It also examines how electoral pressures might constrain or help them in this endeavor