774 resultados para 760103 Consumption patterns, population issues and the environment


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SUMMARYIn the context of the biodiversity crisis, amphibians are experiencing the most severe worldwide decline of all vertebrates and are in urgent need of better management. Efficient conservation strategies rely on sound knowledge of the species biology and of the genetic and demographic processes that might impair their welfare. Nonetheless, these processes are poorly understood in amphibians. Delineating population boundaries remains consequently problematic for these species, while it is of critical importance to define adequate management units for conservation. In this study, our attention focused on the alpine salamander (Salamandra atra), a species that deserves much interest in terms of both conservation biology and evolution. This endemic alpine species shows peculiar life-history traits (viviparity, reduced activity period, slow maturation) and has a slow population turnover, which might be problematic for its persistence in a changing environment. Due to its elusive behaviour (individuals spend most of their time underground and are unavailable for sampling), dynamic processes of gene and individuals were poorly understood for that species. Consequently, its conservation status could hardly be reliably assessed. Similarly the fire salamander (Salamandra salamandra) also poses special challenges for conservation, as no clear demarcation of geographical populations exists and dispersal patterns are poorly known. Through a phylogeographic analysis, we first studied the evolutionary history of the alpine salamander to better document the distribution of the genetic diversity along its geographical range. This study highlighted the presence of multiple divergent lineages in Italy together with a clear genetic divergence between populations from Northern and Dinaric Alps. These signs of cryptic genetic differentiation, which are not accounted for by the current taxonomy of the species, should not be neglected for further definition of conservation units. In addition, our data supported glacial survival of the species in northern peripheral glacial réfugia and nunataks, a pattern rarely documented for long-lived species. Then, we evaluated the level of gene flow between populations at the local scale and tested for asymmetries in male versus female dispersal using both field-based (mark-recapture) and genetic approaches. This study revealed high level of gene flow between populations, which stems mainly from male dispersal. This corroborated the idea that salamanders are much better dispersers than hitherto thought and provided a well- supported example of male-biased dispersal in amphibians. In a third step, based on a mark- recapture survey, we addressed the problem of sampling unavailability in alpine salamanders and evaluated its impact on two monitoring methods. We showed that about three quarters of individuals were unavailable for sampling during sampling sessions, a proportion that can vary with climatic conditions. If not taken into account, these complexities would result in false assumptions on population trends and misdirect conservation efforts. Finally, regarding the daunting task of delineating management units, our attention was drawn on the fire salamander. We conducted a local population genetic study that revealed high levels of gene flow among sampling sites. Management units for this species should consequently be large. Interestingly, despite the presence of several landscape features often reported to act as barriers, genetic breaks occurred at unexpected places. This suggests that landscape features may rather have idiosyncratic effects on population structure. In conclusion, this work brought new insights on both genetic and demographic processes occurring in salamanders. The results suggest that some biological paradigms should be taken with caution when particular species are in focus. Species- specific studies remain thus fundamental for a better understanding of species evolution and conservation, particularly in the context of current global changes.RESUMEDans le contexte de la crise de la biodiversité actuelle, les amphibiens subissent le déclin le plus important de tous les vertébrés et ont urgemment besoin d'une meilleure protection. L'établissement de stratégies de conservation efficaces repose sur des connaissances solides de la biologie des espèces et des processus génétiques et démographiques pouvant menacer leur survie. Ces processus sont néanmoins encore peu étudiés chez les amphibiens.Dans cette étude, notre attention s'est portée sur la salamandre noire (Salamandra atra), une espèce endémique des Alpes dont les traits d'histoire de vie atypiques (viviparité, phase d'activité réduite, lent turnover des populations) pourraient la rendre très vulnérable face aux changements environnementaux. Par ailleurs, en raison de son comportement cryptique (les individus passent la plupart de leur temps sous terre) la dynamique des gènes et des individus est mal comprise chez cette espèce. Il est donc difficile d'évaluer son statut de conservation de manière fiable. La salamandre tachetée {Salamandra salamandra), pour qui il n'existe aucune démarcation géographique apparente des populations, pose également des problèmes en termes de gestion. Dans un premier temps, nous avons étudié l'histoire évolutive de la salamandre noire afin de mieux décrire la distribution de sa diversité génétique au sein de son aire géographique. Cela a permis de mettre en évidence la présence de multiples lignées en Italie, ainsi qu'une nette divergence entre les populations du nord des Alpes et des Alpes dinariques. Ces résultats seront à prendre en compte lorsqu'il s'agira de définir des unités de conservation pour cette espèce. D'autre part, nos données soutiennent l'hypothèse d'une survie glaciaire dans des refuges nordiques périglaciaires ou dans des nunataks, fait rarement documenté pour une espèce longévive. Nous avons ensuite évalué la différentiation génétique des populations à l'échelle locale, ce qui a révélé d'important flux de gènes, ainsi qu'une asymétrie de dispersion en faveur des mâles. Ces résultats corroborent l'idée que les amphibiens dispersent mieux que ce que l'on pensait, et fournissent un exemple robuste de dispersion biaisée en faveur des mâles chez les amphibiens. Nous avons ensuite abordé le problème de Γ inaccessibilité des individus à la capture. Nous avons montré qu'environ trois quarts des individus sont inaccessibles lors des échantillonnages, une proportion qui peut varier en fonction des conditions climatiques. Ignoré, ce processus pourrait entraîner une mauvaise interprétation des fluctuations de populations ainsi qu'une mauvaise allocation des efforts de conservation. Concernant la définition d'unités de gestion pour la salamandre tachetée, nous avons pu mettre en évidence un flux de gènes important entre les sites échantillonnés. Les unités de gestion pour cette espèce devraient donc être étendues. Etonnamment, malgré la présence de nombreuses barrières potentielles au flux de gènes, les démarcations génétiques sont apparues à des endroits inattendus. En conclusion, ce travail a apporté une meilleure compréhension des processus génétiques et démographiques en action chez les salamandres. Les résultats suggèrent que certains paradigmes biologiques devraient être considérés avec précaution quand il s'agit de les appliquer à des espèces particulières. Les études spécifiques demeurent donc fondamentales pour une meilleure compréhension de l'évolution des espèces et leur conservation, tout particulièrement dans le contexte des changements globaux actuels.

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A person’s physical and social environment is considered as an influencing factor in terms of rates of engagement in physical activity. This study analyses the influence of socio-demographic, physical and social environmental factors on physical activity reported in the adult population in Andalusia. This is a cross-sectional study using data collected in the Andalusia Health Survey in 1999 and 2003. In addition to the influence of the individual’s characteristics, if there are no green spaces in the neighbourhood it is less likely that men and women will take exercise (OR = 1.26; 95% CI = 1.13, 1.41). Likewise, a higher local illiteracy rate also has a negative influence on exercise habits in men (OR = 1.39; 95% CI = 1.21, 1.59) and in women (OR = 1.22; 95% CI = 1.07, 1.40). Physical activity is influenced by individuals’ characteristics as well as by their social and physical environment, the most disadvantaged groups are less likely to engage in physical activity

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Discordances exist in epidemiological studies regarding the association between the intake of nutrients and death and disease. We evaluated the social and health profile of persons who consumed olive oil in a prospective population cohort investigation (Pizarra study) with a 6-year follow-up. A food frequency questionnaire and a 7 d quantitative questionnaire were administered to 538 persons. The type of oil used in food preparation was determined by direct measurement of the fatty acids in samples obtained from the kitchens of the participants at baseline and after follow-up for 6 years. The fatty acid composition of the serum phospholipids was used as an endogenous marker of the type of oil consumed. Total fat intake accounted for a mean 40 % of the energy (at baseline and after follow-up). The concordance in intake of MUFA over the study period was high. The fatty acid composition of the serum phospholipids was significantly associated with the type of oil consumed and with fish intake. The concentration of polar compounds and polymers, indicative of degradation, was greater in oils from the kitchens where sunflower oil or refined olive oil was used, in oils used for deep frying and in oils that had been reused for frying five times or more. Consumption of olive oil was directly associated with educational level. Part of the discordance found in epidemiological studies between diet and health may be due to the handling of oils during food preparation. The intake of olive oil is associated with other healthy habits.

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OBJECTIVE To describe and compare the consumption of the main groups and sub-groups of vegetables and fruits (V&F) in men and women from the centres participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). DESIGN Cross-sectional analysis. Dietary intake was assessed by means of a 24-hour dietary recall using computerised interview software and standardised procedures. Crude and adjusted means were computed for the main groups and sub-groups of V&F by centre, separately for men and women. Adjusted means by season, day of the week and age were estimated using weights and covariance analysis. SETTING Twenty-seven centres in 10 European countries participating in the EPIC project. SUBJECTS In total, 35 955 subjects (13 031 men and 22 924 women), aged 35-74 years, randomly selected from each EPIC cohort. RESULTS The centres from southern countries had the highest consumption of V&F, while the lowest intake was seen in The Netherlands and Scandinavia for both genders. These differences were more evident for fruits, particularly citrus. However, slightly different patterns arose for some sub-groups of vegetables, such as root vegetables and cabbage. Adjustment for body mass index, physical activity, smoking habits and education did not substantially modify the mean intakes of vegetables and fruits. CONCLUSIONS Total vegetable and fruit intake follows a south-north gradient in both genders, whereas for several sub-groups of vegetables a different geographic distribution exists. Differences in mean intake of V&F by centre were not explained by lifestyle factors associated with V&F intake.

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A person's physical and social environment is considered as an influencing factor in terms of rates of engagement in physical activity. This study analyses the influence of socio-demographic, physical and social environmental factors on physical activity reported in the adult population in Andalusia. This is a cross-sectional study using data collected in the Andalusia Health Survey in 1999 and 2003. In addition to the influence of the individual's characteristics, if there are no green spaces in the neighbourhood it is less likely that men and women will take exercise (OR = 1.26; 95% CI = 1.13, 1.41). Likewise, a higher local illiteracy rate also has a negative influence on exercise habits in men (OR = 1.39; 95% CI = 1.21, 1.59) and in women (OR = 1.22; 95% CI = 1.07, 1.40). Physical activity is influenced by individuals' characteristics as well as by their social and physical environment, the most disadvantaged groups are less likely to engage in physical activity.

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BACKGROUND: Little is known about engagement in multiple health behaviours in childhood cancer survivors. METHODS: Using latent class analysis, we identified health behaviour patterns in 835 adult survivors of childhood cancer (age 20-35 years) and 1670 age- and sex-matched controls from the general population. Behaviour groups were determined from replies to questions on smoking, drinking, cannabis use, sporting activities, diet, sun protection and skin examination. RESULTS: The model identified four health behaviour patterns: 'risk-avoidance', with a generally healthy behaviour; 'moderate drinking', with higher levels of sporting activities, but moderate alcohol-consumption; 'risk-taking', engaging in several risk behaviours; and 'smoking', smoking but not drinking. Similar proportions of survivors and controls fell into the 'risk-avoiding' (42% vs 44%) and the 'risk-taking' cluster (14% vs 12%), but more survivors were in the 'moderate drinking' (39% vs 28%) and fewer in the 'smoking' cluster (5% vs 16%). Determinants of health behaviour clusters were gender, migration background, income and therapy. CONCLUSION: A comparable proportion of childhood cancer survivors as in the general population engage in multiple health-compromising behaviours. Because of increased vulnerability of survivors, multiple risk behaviours should be addressed in targeted health interventions.

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In this paper we attempt to describe the general reasons behind the world populationexplosion in the 20th century. The size of the population at the end of the century inquestion, deemed excessive by some, was a consequence of a dramatic improvementin life expectancies, attributable, in turn, to scientific innovation, the circulation ofinformation and economic growth. Nevertheless, fertility is a variable that plays acrucial role in differences in demographic growth. We identify infant mortality, femaleeducation levels and racial identity as important exogenous variables affecting fertility.It is estimated that in poor countries one additional year of primary schooling forwomen leads to 0.614 child less per couple on average (worldwide). While it may bepossible to identify a global tendency towards convergence in demographic trends,particular attention should be paid to the case of Africa, not only due to its differentdemographic patterns, but also because much of the continent's population has yet toexperience improvement in quality of life generally enjoyed across the rest of theplanet.

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BACKGROUND: Studies carried out on specific travelers' groups such as students describe an increase in the consumption of alcohol and drugs during travel and vacation time. The present study investigates the risk behaviors (alcohol and drugs) in a general adult population in Switzerland travelling abroad who visited a travel clinic before departure. METHODS: This retrospective study was conducted in a travel clinic between January 2006 and December 2008. 14,496 patients came to the clinic for a pre-travel consultation. 3,537 of them answered a questionnaire about their life habits in Switzerland and during their last trip. The only exclusion criterion was an age inferior to 18 years old.The consumption habits of drugs and at-risk alcohol intake (8 standard drinks (SD) per week for women and 15 SD for men) was analyzed according to gender, sex, destination and profession. Predictors of adopting a risky behavior between habits in Switzerland and during their previous trip were also analyzed. RESULTS: 7% (229/3477) of participants declared having at-risk alcohol consumption in Switzerland and 14% (473/3275 [95% CI 13-16]) during their trip. 9% (332/3527) of the participants used drugs in Switzerland and 5% (178/3481) during their trip. Risk factors for at-risk alcohol consumption during a trip were: at-risk alcohol consumption in Switzerland (OR 31[95% CI 21-45]), smoking (1.7 [95% CI 1-2]), use of drugs in Switzerland (OR 2.2 [95% CI 2-3]), leisure travel (OR 1.6 [95% CI 1-2]) and managerial professions (OR 1.8 [95% CI 1-3]). Risk factors for the use of drugs during a trip were: alcohol consumption in Switzerland (OR 2.1 [95% CI 1-4]), smoking (OR 1.9 [95% CI 1-3]), and use of drugs in Switzerland (OR 29.7 [95% CI 19-45]). CONCLUSIONS: At-risk alcohol consumption and, to a lesser extent, use of drugs, affect a large number of travelers which expose them to health problems during a trip. Exploring the alcohol and drugs consumption patterns of people visiting a travel clinic should be part of the pre-travel routine consultation and would allow to identifying people who would benefit most from a specific prevention.

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Neutral and selective processes c an drive repeated patterns of evolu tion in dif ferent groups of populationsexp eriencing similar ecol ogica l gradients. In this paper, we used a combinat ion of nucl ear and mitochondrialDNA markers, as well as geometric morphometrics, to investigate repeated patterns of morphological andgenetic divergence of E uropean minnows in two mountain ranges : the Pyrenees and the Al ps. Europeanminnows (Phoxinus phoxinus) are cyprinid fish i nha bitin g most freshwater bodies in Europe, including those indifferent mountain r anges that could act as major geographical barriers to gene flow. We explored patterns ofP. phoxinus phenotypic and genetic di versi fication along a gradi ent of alti tude common to the two mountainranges, and tested for isolation by distance (IBD), isolation by environment (IBE) and isolation by adaptation(IBA). The results indicated that populations from the Pyr enees a nd the Alps bel ong to two well differentiated,reciprocally monophyletic mt DNA lineages. Substantial genetic differentiation due to geographical isolationwithin and between populations from the Pyrenees and the Alps was also found using rapidly evolving AFLPsmarkers (isolation by distance or IBD), as well as morphological differences between mountain ranges. Als o,morphology varied strong ly with elevation and so did genetic differentiation to a lower extent. Despitemoderate evidence for IBE and IBA, and therefore of repeated evolution, substantial population heterogeneitywas found at the genetic level, suggesting that selection and population specific genetic drift act in concert toaffect genetic divergence.

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Organochlorine compounds (OC) are known to induce vitamin A (retinoids) deficiency in mammals, which may be associated with impairment of immunocompetence, reproduction and growth. This makes retinoids a potentially useful biomarker of organochlorine impact on marine mammals. However, use of retinoids as a biomarker requires knowledge about its intrapopulation patterns of variation in natural conditions, information which is not currently available. We investigated these patterns in a cetacean population living in an unpolluted environment. 100 harbour porpoises Phocoena phocoena from West Greenland were sampled during the 1995 hunting season. Sex, age, morphometrics, nutritive condition, and retinol (following saponification) and OC levels in blubber were determined for each individual. OC levels found were extremely low and therefore considered unlikely to affect the population adversely: mean blubber concentrations, expressed on an extractable basis, were 2.04 (SD = 1.1) ppm for PCBs and 2.76 (SD = 1.66) ppm for tDDT. The mean blubber retinol concentration for the overall population was 59.66 (SD = 45.26) mu g g(-1). Taking into account the high contribution of blubber to body mass, blubber constitutes a significant body site for retinoid deposition in harbour porpoises. Retinol concentrations did not differ significantly between geographical regions or sexes, but they did correlate significantly (p <0.001) with age. Body condition, measured by determining the lipid content of the blubber, did not have a significant effect on retinol levels but the individuals examined were considered to be in an overall good nutritive condition. It is concluded that measurement of retinol concentrations in blubber samples is feasible and has a potential for use as a biomarker of organochlorine exposure in cetaceans. However, in order to do so, biological information, particularly age, is critical for the correct assessment of physiological impact

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Avhandlingen handlar om hur kompositionen hos litoralt djurplankton varierar med omgivningens trofiska nivå (m.a.o. eutrofieringsgrad). Arbetets inledande mål är att beskriva hur mängden och artmångfalden hos djurplankton i strandnära vattnen och de omgivande organismsamhällen ändras med närsaltshalter. Huvudsyftet är att utreda allmänna mekanismer som styr dessa mönster och som på så sätt kan vara viktiga i att reglera samhällen även i andra ekologiska system. Undersökningarna gjordes i åländska flador över flera tillväxtsäsonger samt i laboratorier där omgivningsförhållanden i fladorna kunde simuleras och manipuleras. Djurplankton i dessa lagunlika vikar är lägliga modellsystem. Flador är lämpligt avgränsade från det omgivande havet och förekommer allmänt i norra Östersjöregionen. Således kan de inom ett litet område som Åland representera hela regionala gradienten från näringsfattiga till näringsrika förhållanden. De små kräft- och hjuldjuren som djurplankton består av befinner sig i mitten av näringsväven. De sammankopplar olika typer av mikrobiell produktion vidare till högre konsumenter och är på så sätt centrala för organismsamhällens struktur och funktion i nästan alla akvatiska miljöer. I likhet med primärproducenterna (d.v.s. växter och alger som direkt påverkas av närsaltshalterna, och som bl.a. utgör föda och habitat för djurplankton) samvarierar kompositionen hos djurplankton tydligt med omgivningens trofiska nivå tills den blir hög. Sedan börjar hela samhällskompositionen utveckla sig åt två skilda håll. Dessa mönster kan för djurplanktonets del förklaras med att dess komposition ingalunda styrs endast av primärproducenterna, utan av ett komplicerat samspel mellan dessa resurser samt konkurrerande och högre konsumenter (d.v.s. predatorer på flera högre trofinivåer). Detta kom fram speciellt i laboratorieförhållanden då kompositionen hos dessa samhällskomponenter manipulerades. Både deras sammansättning och relativa tätheter i sig, samt en kombination av båda visade sig styra djurplanktonkompositionen. Lokala processer (inom fladorna) och synnerligen förändringar hos olika fundament- (speciellt vass, borstnate och rödsträfse), kärn- (speciellt yngel av a bborre och mört) och nyckelarter (stora predatorer som gädda) verkar kunna avgöra till vilken grad djurplanktonkompositionen samvarierar med omgivningens trofiska nivå. Inte bara samhällen utan också de mekanismer som styr dem ändras med omgivningens trofiska nivå. Flador är ypperliga naturliga laboratorier för att studera dessa och även andra allmänekologiska mönster och mekanismer. De är också oerhört viktiga miljöer för hela kustregionens natur.

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Thousands of tons of pharmaceuticals are consumed yearly worldwide. Due to the continuous and increasing consumption and their incomplete elimination in wastewater treatment plants (WWTP), pharmaceuticals and their metabolites can be detected in receiving waters, although at low concentrations (ng to low μg/L). As bioactive molecules the presence of pharmaceuticals in the aquatic environment must be considered potentially hazardous for the aquatic organisms. In this thesis, the biotransformation and excretion of pharmaceuticals in fish was studied. The main biotransformation pathways of three anti‐inflammatory drugs, diclofenac, naproxen and ibuprofen, in rainbow trout were glucuronidation and taurine conjugation of the parent compounds and their phase I metabolites. The same metabolites were present in fish bile in aquatic exposures as in fish dosed with intraperitoneal injection. Higher bioconcentration factor in bile (BCFbile) was found for ibuprofen when compared to diclofenac and naproxen. Laboratory exposure studies were followed by a study of uptake of pharmaceuticals in a wild fish population living in lake contaminated with WWTP effluents. Of the analyzed 17 pharmaceuticals and six phase I metabolites, only diclofenac, naproxen and ibuprofen was present in bream and roach bile. It was shown, that diclofenac, naproxen and ibuprofen excreted by the liver can be found in rainbow trout and in two native fish species living in the receiving waters. In the bream and roach bile, the concentrations of diclofenac, naproxen and ibuprofen were roughly 1000 times higher than those found in the lake water, while in the laboratory exposures, the bioconcentration of the compounds and their metabolites in rainbow trout bile were at the same level as in wild fish or an order of magnitude higher. Thus, the parent compounds and their metabolites in fish bile can be used as a reliable biomarker to monitor the exposure of fish to environmental pharmaceuticals present in water receiving discharges from WWTPs.

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The development of computer and network technology is changing the education scenario and transforming the teaching and learning process from the traditional physical environment to the digital environment. It is now possible to access vast amount of information online and enable one to one communication without the confines of place or time. While E-learning and teaching is unlikely to replace face-to-face training and education it is becoming an additional delivery method, providing new learning opportunities to many users. It is also causing an impact on library services as the increased use of ICT and web based learning technologies have paved the way for providing new ICT based services and resources to the users. Online learning has a crucial role in user education, information literacy programmes and in training the library professionals. It can help students become active learners, and libraries will have to play a greater role in this process of transformation. The significance of libraries within an institution has improved due to the fact that academic libraries and information services are now responsible for e-learning within their organization.