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There is considerable ambiguity around the importance of demographic and socio-economic characteristics that catalyze pro-environmental behaviours. These factors are typically deemed responsible for environmental skepticism, such as the degree of trust in social institutions, fundamental views of the individuals (e.g., religiosity and political ideology), and competing priorities. In this context, the present study analyzed a comprehensive dataset of survey responses to discern the most reliable predictors of environmental attitudes of Canadians related to activism, lifestyle, household practices on air quality, waste disposal, energy and water conservation. To achieve this objective, we capitalize upon the wealth of publicly available data from surveys conducted by Statistics Canada's Households and the Environment Survey. Our analysis suggests that individuals with university-level education and higher income or families with children generally display pro-environmental behaviours. Political conservatism, as expressed by the percentage vote for the Progressive Conservative Party of Canada in a given area, appears to covary with some facets of the documented reluctance to embrace environmentally aligned behaviours (i.e., climate change issues), although we did not find a major “conservative-versus-liberal” divide about the broader spectrum of environmental issues. Our assessment of environmental attitudes in different Canadian provinces suggests an aptitude for more sustainable living in Ontario and British Columbia. Our analysis also provides evidence that the intent to support efforts that reduce emissions from burning fossil fuels or promote clean energy and technology – which has been overwhelmingly communicated in recent national polls – is not necessarily actualized. This established trend of Canadians failing to “walk the talk” and materialize their stated commitment with tangible participation into environmentally supportive behaviours could stem from barriers imposed at the household and societal levels. Notwithstanding the uncertainty regarding the importance of different socio-demographic factors in shaping our predisposition and behaviour towards environmental issues, the findings of our study offer a working model that could allow addressing the roots of environmental skepticism, promote societal trust, and revisit the role of ecopolitics in the social agenda.  相似文献   

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Lang T  Jahn R 《Developmental cell》2002,2(3):257-259
In the February 8th issue of Cell, Wang et al. report the surprising finding that vacuolar fusion occurs at the periphery of the contact area of the vacuoles and not by the expansion of a central fusion pore. During fusion, a disk of boundary membrane is excised and left behind within the fused vacuoles.  相似文献   

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Ecological theories of sexual reproduction assume that sexuality is advantageous in certain conditions, for example, in biotically or abiotically more heterogeneous environments. Such theories thus could be tested by comparative studies. However, the published results of these studies are rather unconvincing. Here, we present the results of a new comparative study based exclusively on the ancient asexual clades. The association with biotically or abiotically homogeneous environments in these asexual clades was compared with the same association in their sister, or closely related, sexual clades. Using the conservative definition of ancient asexuals (i.e., age >1 million years), we found eight pairs of taxa of sexual and asexual species, six differing in the heterogeneity of their inhabited environment on the basis of available data. The difference between the environmental type associated with the sexual and asexual species was then compared in an exact binomial test. The results showed that the majority of ancient asexual clades tend to be associated with biotically, abiotically, or both biotically and abiotically more homogeneous environments than their sexual controls. In the exploratory part of the study, we found that the ancient asexuals often have durable resting stages, enabling life in subjectively homogeneous environments, live in the absence of intense biotic interactions, and are very often sedentary, inhabiting benthos, and soil. The consequences of these findings for the ecological theories of sexual reproduction are discussed.  相似文献   

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Plant responses to biotic and abiotic stresses are usually accompanied by the release of reactive oxygen species including hydrogen peroxide. Hydrogen peroxide plays a direct role in defense and is involved in many signal transduction pathways that lead to the proliferation of other defenses. Because catalase helps to maintain reactive oxygen homeostasis during biotic and abiotic stress, its activity was measured in various cob tissues during maize ear development. Catalase activity was determined in immature and mature embryos, pericarp, and rachis tissues of maize lines that are resistant and susceptible to Aspergillus flavus infection. The effect of fungal inoculation on catalase activity was also measured. Over two years of field experimentation, a correlation was observed between resistance and the level of catalase-specific activity in immature embryos, which was significantly higher in resistant lines (P < 0.0001). Furthermore, catalase activity in the resistant lines was significantly higher in immature embryos from inoculated ears (P = 0.0199). No correlation was observed between resistance and catalase activity in other ear tissues. Levels of hydrogen peroxide, the catalase substrate, and salicylic acid in the embryo were also determined. The resistant lines showed lower levels of H2O2 (P < 0.0001) and higher levels of salicylic acid (P < 0.0001) as compared with the susceptible lines. Catalase 3 was sequenced from the aflatoxin-resistant (Mp313E) and susceptible (SC212m) inbreds. The predicted amino acid sequence indicated that there was a 20-aa deletion in the resistant inbred that might affect enzymatic activity. Unlike many plant-pathogen interactions, it appears that lowering H2O2 levels helps to prevent A. flavus infection and subsequent aflatoxin accumulation.  相似文献   

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Association study is the method of choice to identify genes involved in complex processes that result from the interaction of environmental and genetic factors. However, because of biases that increase the risk of false positive reports, preliminary positive conclusions have to be reproduced on other populations to be validated as firm conclusions. In 1994, certain alleles of two genes, APOE (Apolipoprotein E) and ACE (angiotensin converting enzyme), were reported to be more frequent in French centenarians, suggesting an association with such a complex polyfactorial process as longevity. Enlargement of the French centenarian cohort allows a new assessment of this hypothesis on 563 centenarians. In contrast to APOE, the ACE association was not confirmed. Retrospective analysis of the initial study revealed discrepancies that may in part explain this observation. Risk of reporting false positive associations is discussed and recommendations to set up a rigorous experimental design are proposed.  相似文献   

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The objective of the study was to examine which cultured endometrial cells are the source and which are the target for lysophosphatidic acid (LPA) in the bovine uterus. LPA concentration as well as mRNA and protein expressions of the enzymes responsible for LPA synthesis (phospholipase A2: PLA2, autotaxin: AX) were greater in epithelial than in stromal cells (P < 0.05). In turn, mRNA and protein expression of LPA receptor (LPAR1) was lower in epithelial than in stromal cells (P < 0.05). We suggest that LPA in bovine endometrium is produced mainly by epithelial cells and affects mostly stromal cells acting via LPAR1.  相似文献   

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Background

Identifying factors influencing plant management allows understanding how processes of domestication operate. Uncertain availability of resources is a main motivation for managing edible plants, but little is known about management motives of non-edible resources like medicinal and ceremonial plants. We hypothesized that uncertain availability of resources would be a general factor motivating their management, but other motives could operate simultaneously. Uncertainty and risk might be less important motives in medicinal than in edible plants, while for ceremonial plants, symbolic and spiritual values would be more relevant.

Methods

We inventoried edible, medicinal, and ceremonial plants in Ixcatlán, Oaxaca, Mexico, and conducted in-depth studies with 20 native and naturalized species per use type; we documented their cultural importance and abundance by interviewing 25 households and sampling vegetation in 33 sites. Consumption amounts and preferences were studied through surveys and free listings with 38 interviewees. Management intensity and risk indexes were calculated through PCA and their relation analyzed through regression analyses. Canonical methods allowed identifying the main sociocultural and ecological factors influencing management of plants per use type.

Results

Nearly 64, 63, and 55% of all ceremonial, edible, and medicinal wild plants recorded, respectively, are managed in order to maintain or increase their availability, embellishing environments, and because of ethical reasons and curiosity. Management intensity was higher in edible plants under human selection and associated with risk. Management of ceremonial and medicinal plants was not associated with indexes of risk or uncertainty in their availability. Other sociocultural and ecological factors influence management intensity, the most important being reciprocal relations and abundance perception.

Conclusions

Plant management through practices and collectively regulated strategies is strongly related to control of risk and uncertainty in edible plants, compared with medicinal and ceremonial plants, in which reciprocal interchanges, curiosity, and spiritual values are more important factors. Understanding how needs, worries, social relations, and ethical values influence management decisions is important to understand processes of constructing management strategies and how domestication could be started in the past and are operated at the present.
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Objectives: To determine the prevalence of the pathogenic strain of Neisseria meningitidis in contacts of patients with meningococcal disease, and to determine which contact groups are likely to be carriers and warrant chemoprophylaxis. Design: Population based study. Setting: Norwegian county of Telemark. Subjects: 1535 primary contacts of 48 patients with meningococcal disease, and 78 secondary contacts. Interventions: Carriers of the pathogenic strain were treated with rifampicin. All household members and kissing contacts under 15 years of age were treated with oral penicillin. Contacts were taught to recognise the symptoms of meningococcal disease. Results: In 27 of 48 cases investigated, contacts carrying the pathogenic strain of N meningitidis were found. A total of 42 such contacts were identified. Contacts were stratified into three classes according to the assumed closeness of contact with patients. In class 1 (household members and kissing contacts) the prevalence of the pathogenic strain was 12.4% (95% confidence interval 5.5% to 19.3%). In classes 2 and 3 the prevalence was 1.9% (0.9% to 3.4%) and 1.6% (0.14% to 3.1%). Conclusions: There is a high rate of carriage of the pathogenic strain of N meningitidis in patients’ household members and kissing contacts, and this supports the practice of giving chemoprophylaxis to these contacts. The prevalence of carriage among other contacts is 2-3 times that found in the general population (0.7%); the benefits of chemoprophylaxis to these contacts may be marginal.

Key messages

  • Contacts of patients with meningococcal disease have a 12.4% (95% confidence interval 5.5% to 19.3%) risk of carrying the pathogenic meningococcus if they are kissing contacts or household members
  • The risk of carriage of the pathogenic strain for two groups of contacts less close than household members or kissing contacts is 1.9% (0.9% to 3.4%) and 1.6% (0.14% to 3.1%)
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Orchid species that are food mimics produce fewer fruits than species offering rewards, but few studies have shown the impact of environmental factors (e.g. anthropogenic activity, frost and herbivores) on their reproductive success over several seasons. In this study, we focused on the sole population of the endangered Calanthe yaoshanensis as it secretes no nectar. We investigated its floral biology, fruit set rates and prevailing environmental factors over three seasons (2008–2010). Mechanical self‐pollination did not occur in C. yaoshanensis, but hand‐selfed and crossed flowers produced equal numbers of fruit. However, seed viability and embryo size were significantly higher in cross‐pollinated fruits maximizing embryonic fitness. Large hoverflies (Syrphidae) and Bombus patagiatus (gynes) were the only pollinarium vectors, but they often failed to disperse pollinaria. We interpret the temporary retention of the anther cap over the pollinarium as an adaptation lowering self‐pollination. Insect‐mediated rates of pollinarium removal were always higher than rates of pollinia deposition on stigmas. Over 3 years, natural rates of pollinarium removal differed significantly, whereas natural rates of fruit set were not significantly different (< 22%). Climate, herbivory and anthropogenic collections also inhibited some fruit set and maturation. Both biotic and abiotic factors appear to lower the fecundity of this endangered population. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 421–433.  相似文献   

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Purpose: GSTM1 and GSTT1 present a polymorphism that can drive complete gene deletions. The current methodology can powerfully determine GSTM1 and GSTT1 copy number variations (CNVs), which may clarify the real contribution of each gene copies to the cellular detoxification process and tumour risk. However, only analysing the presence/absence of these genes yielded controversial results for several disorders, including cancer. Because head and neck cancer (HNC) is becoming a serious global health problem, this study determined the CNVs of GSTM1 and GSTT1 in an HNC case-control population and investigated the possible association between gene copy numbers and tumour risk.

Methods: CNV was evaluated by (Ct) 2?ΔΔCt qPCR methodology in 619 HNC patients and 448 patients with no tumour diagnosis.

Results: The genes copy number range was 0–3. The CNV of GSTM1 and GSTT1 frequencies were similar between the cases and control. Thus, none copy of GSTM1 and GSTT1 were associated with HNC risk. Notwithstanding, one copy of both genes had higher frequencies among individuals who carried GSTM1 and GSTT1.

Conclusions: One copy number of GSTM1 and GSTT1 presented a higher frequency among carrier genes, but the CNV of GSTM1 and GSTT1 was not associated with HNC risk.  相似文献   


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We analysed bearded vulture (Gypaetus barbatus) occurrences collected through long-term monitoring (from 1993 to 2010) in the Western Alps (1) to test whether ecological niches shift due to individual development and (2) to verify whether these patterns could reflect their spatial distribution. Thus, we compared the distribution patterns of three age classes (‘young’, ‘sub-adults’ and ‘adults’) through the K-select analysis. We then computed ten species distribution models (SDMs) and their average prediction to test for differences in age class distribution. The K-select analysis showed highly significant differences in the ecological niche among all the age classes and we also found highly significant differences in all the SDMs among the three age classes considered. Our results quantitatively showed that target species exhibits age specific shifts in the ecological niche and changes in the spatial distribution of individuals. Our methods are potentially widely applicable for testing differences among age classes of other species and thus, defining the best conservation actions (such as re-introduction) by taking into account different requirements in different stages of the individuals’ life.  相似文献   

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