Jean-Pierre Thouez

Impacts of a Ghg-Induced Climate Change on Crop Yields: Effects of Acceleration in Maturation, Moisture Stress and Optimal Temperature

The present study involves using the Canadian Climate Centre (CCC) climate change scenario to evaluate the impacts of a CO2-induced climate change on agriculture in Québec and vicinity. Climate change using the CCC General Circulation Model (GCM) data are fed into a crop model (FAO) so as to gauge the changes in agroclimatic factors such as growing season length and growing degree days, and subsequently potential yield changes for a variety of cereal (C3 and C4), leguminous, oleaginous, vegetable and special crops, for twelve major agricultural regions in southern Québec. Our results show that depending upon the agricultural zone and crop type, yields may increase (ex. corn and sorghum by 20%) or decrease (ex. wheat and soybean by 20 to 30%). Also, these crop yield changes appear to be related to acceleration in maturation rates, mainly to change in moisture stress and to shifts in optimal thermal growth conditions. These possible shifts in agricultural production potentials would solicit the formulation of appropriate adaptation strategies.

Neurodegenerative diseases and risk factors: A literature review

Degenerative diseases of the central nervous system are significant causes of mortality among elderly people in industrialized countries. For the most part, the causes of these diseases are unknown. It is also very difficult to diagnose this type of disease quickly and accurately. This article reviews the epidemiological research on the principal neurodegenerative disorders, focusing on geographical, hereditary and viral and toxicological exposure correlates. We look in particular at the effect of exposure to toxins as well as the effect that deficiencies of elements such as calcium and selenium could have on the development of these neurological diseases. We also consider the possible protectionist effect of some variables on the development of certain neurological diseases.

The effects of climatic change and C02 fertilisation on agriculture in Québec

Abstract The agricultural sector forms an important part of the economy of Quebec. The risk of global increase of atmospheric CO 2 concentration and associated climatic change and their influence on agriculture need to be assessed. Although many studies have been conducted on the effect of climate change on agriculture in various parts of the world, fewer studies have focused on the combined effects of climatic change and CO 2 fertilisation on agriculture. This study, using the outputs of the Canadian Climate Centre (CCC) general circulation model coupled with the Food and Agricultural Organization (FAO) crop model, attempts to assess the response of agricultural productivity to both direct (or fertilisation) and indirect (or climatic) effects of increased atmospheric CO 2 concentration, for a variety of crops including C 3 and C 4 cereals, legumes, vegetables and special crops grown in Quebec. It appears that Ca cereal (corn and sorghum) crops would benefit by climate change but would be least favoured by CO 2 fertilisation effect.

Cancer and the physicochemical quality of drinking water in Quebec

Abstract The science of Medical Geography permits the delineation of maps of illness using different scales to compare the factors of incidence of a disease. The identification of differences in risk according to population and region facilitates the elaboration of ecological hypotheses relative to the cause of disease. Cancer in humans is an illness of high frequency in our society. According to the most recent Canadian statistics it is in Quebec that the risk of being a cancer victim is the greatest in this country. During the years 1970–1972 Quebec males registered the highest frequency for the ensemble of seats of cancer, while Quebec females ranked directly after those of Nova Scotia. In addition, cancer remains one of the illnesses where environmental agents may exercise a determinant role. Certain experts consider that the direct or indirect dependence upon environmental factors applies in 80 to 90% of cancer cases. To establish the geographic location of cancers in Quebec we have used figures supplied by Statistics Canada for census regions (R.R.I of Quebec. We have taken the number of new cases of malignant tumors observed during the year for each type of tumor figuring in the international classification of illnesses for a period of 5 years that is from 1970–1975. These figures indicate the rates of incidence of a specific cancer observed during the period in question and allow us to calculate the ratio of incidence standardized according to age (SIR) in order to analyze the incidence of malignant tumors in the various census regions. The objective of this study was to discover the possible relation between the quality of drinking water and cancer. More particularly, we think that certain cancers are more prevalent in regions where the water is considered “soft”. To establish this relation we grouped the R.R. by sites of cancer in two groups: one where the SIR was high and one where the SIR was low. The R.R. of less than 10 cases of cancer per year were eliminated. We then compared the R.R. of high and low rates of incidence according to physicochemical parameters of drinking water as per 1974–1976 observational data. The analysis of correlations and multiple regression were used to evaluate the significant associations.

Correlates of health-care use: Inuit and cree of Northern Quebec

This case study of the use of health-care services in northern Quebec is the first of a series of reports dealing with the health status, risk factors and access to care of the two major aboriginal populations in this region, the Cree and the Inuit. The focus of the broader study is on the health status and risk factors in these native populations. This research, based on a survey conducted in 1983-84, describes the present health status and health-care system of the Cree and Inuit, then presents a path analysis model of their use of health services. The purpose of this approach is to provide health planners and care providers with useful information and to encourage the development of well-organized and reasonable health-care service delivery to these populations.

Epidemiology of obesity in relationship to some chronic medical conditions among Inuit and Cree Indian populations in New Quebec, Canada

The tremendous sociocultural, economic and environmental changes in North American native populations over the last 50 years have been accompanied by the appearance of new public health problems. The prevalence of ‘lifestyle’ diseases, obesity, hypertension and non-insulin dependent diabetes is increasing [1,2]. Disease patterns among Arctic populations are also changing following the introduction of Western culture and technology. Epidemiologic monitoring of specific health problems, for instance chronic diseases such as obesity, diabetes and hypertension is important if we are to understand this continuing process of acculturation. To our knowledge, ours was the first population-based screening for these chronic conditions among native populations of New Quebec. Our survey, which examined obesity, blood glucose levels, cholesterol and blood pressure in the native populations in New Quebec, is part of a continuous epidemiologic monitoring of the health status of the Cree and Inuit Indians in this peripolar region.

Vasectomy and prostate cancer in Quebec Canada.

The present investigation measured the association between vasectomy and prostate cancer (PC) in the male population of Québec, Canada. The Québec Health Insurance Board and the Québec Cancer Registry were our principal sources of information. Lung cancer cases and the male population of Québec served as controls for comparative purposes. Within a retrospective design, our preliminary results indicate an association between vasectomy and PC. Among the 1925-39 birth cohort of individuals diagnosed with PC in 1990--93, the global odds ratio was 2.6 (95% CI=1.7--4.3) while it was compared with lung cancer as the control group. This risk increased with the length of time between vasectomy and the diagnosis of cancer. An historical design indicated strong cohesion of the results. Besides, the risk does not vary when we control for the place of residence of the individuals. Vasectomy seems to increase the risk of PC at least 10 years after the operation, but we cannot exclude the impact of a possible detection bias among vasectomized individuals.

Influence d'un changement climatique dû à une hausse de gaz à effet de serre sur l'agriculture au quebec

Abstract This study, using a climate change scenario generated by the Canadian Climate Centre (CCC) general circulation model (GCM) examines the impacts of such a climate change on agriculture in s...

Ambient air concentrations of asbestos fibers near the town of Asbestos, Québec.

Ambient air concentrations of asbestos fibers were measured during the period June 20 to August 12, 1980, at three locations; Danville, Asbestos, and Wottenville in the eastern townships of Quebec. Measurements were done with low-volume samplers and measurement periods extended from 3 to 13 days. Fiber counts were done by means of electron microscopy. Results indicate that overall fiber concentrations are related to atmospheric stability and to the direction of the prevailing wind with respect to the source of emission.

La mortalite differentielle par cancer suivant le milieu social: Le cas de la region metropolitaine de Montreal, 1971☆

Abstract Cancer mortality rates vary from area to area. Part of this variation is due to socio-economic characteristics of the area and part to other factors including the availability of health services. Three social indicators associated with cancer mortality are used to estimate variations between low and high census sectors within the metropolitan region of Montreal. The components of socio-economic status which have been used are revenue (median family income), education (college and university level) and occupation (higher status profession). For each of the three zones of the metropolitan area: the city of Montreal, the island of Montreal not included the city of Montreal, the north and south shores of the metropolitan area twenty five census sectors have been chosen which having higher or lower positions for each of the socio-economic components. For each group standardized death rates were evaluated for each type of cancer and the Poisson test was applied to judge whether the differences between the projected rate and the observed rate were significant. The results indicate a strong indirect relation between the standardized mortality rates and the socio-economic status in the central city. In the case of lung cancer, the spatial distribution showed district gradients of occurrence between the central-city and the suburbs.