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131.
Conservation Prioritization Using GAP Data   总被引:7,自引:0,他引:7  
Data collected by the Gap Analysis Program in the state of Idaho (U.S.A.) are used to prioritize the selection of locations for conservation action and research. Set coverage and integer programming algorithms provide a sequence of localities that maximize the number of species or vegetation classes represented at each step. Richness maps of vegetation cover class diversity, terrestrial vertebrate species diversity ("hot spot analysis"), endangered, threatened, and candidate species diversity, and unprotected vertebrate species diversity ("gap analysis"), when prioritized, show a rapid accumulation of species as more localities are chosen for terrestrial vertebrates and unprotected vertebrates. Gap analysis identifies four target areas ("gaps") that include 79 of the 83 vertebrate species not currently protected. Accumulation of vegetation cover classes and endangered, threatened, and candidate species is much slower. Sweep analysis is used to determine how well prioritizing on one component of diversity accumulates other components. Endangered, threatened, and candidate species do not sweep total vertebrates as well as unprotected vertebrates do, but are better than vegetation classes. Total vertebrates sweep endangered, threatened, and candidate species better than unprotected vertebrates do, which in turn are better than vegetation classes. We emphasize that prioritization must be part of conservation efforts at multiple scales and that prioritization points out important localities where more detailed work mast be undertaken.  相似文献   
132.
We report a case of maternal uniparental disomy 2, detected through routine screening of placental karyotypes following the finding of ‘atypical’ AFP/hCG levels in the second trimester, with intrauterine growth retardation (IUGR) but otherwise normal outcome at term. Although the child remained small, subsequent early physical and mental development has also been normal. Additionally, we report long-term follow-up of an earlier case, again with relatively normal physical and mental development. The significance of atypical AFP/hCG results and the predictive value of prenatal testing for UPD2 in trisomy 2 confined placental mosaicism (CPM) cases are discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
133.
Objective: This study examined whether reward and punishment sensitivities, as conceptualized by Gray and McNaughton's revised reinforcement sensitivity theory (RST), influenced young female drivers' attention toward a series of positive and negative antispeeding advertisement images. Young females' increasing crash risk is associated with their engagement in risky behaviors, which, in turn, has been associated with a stronger behavioral approach system (BAS; sensitive to rewards). It was predicted that individuals with a stronger BAS would elicit larger N100 and N200 mean amplitudes (reflecting greater attention) toward the positive images. Similar associations were predicted in relation to the fight–flight–freeze system (FFFS; sensitive to punishments) for negative images.

Method: Twenty-four female drivers (17–25 years; final N = 16) completed Corr-Cooper's RST-Personality Questionnaire, prior to undergoing an event-related potential computerized visual task (i.e., oddball paradigm) that included positive, negative, and neutral images as targets against checkerboard image distractors.

Results: Contrary to expectations, individuals with a stronger BAS (Reward Reactivity and Impulsivity) demonstrated significantly larger N200 mean amplitudes at the Cz electrode site on presentation of the negative images than those with a weaker BAS. No other significant RST effects were found.

Conclusions: These findings provide some preliminary objective support for the use of negative emotion-based road safety advertisements for young females. Further, this study provides support for using psychophysiological measures to enhance understanding of traffic injury persuasion.  相似文献   

134.
Why do people get involved in the creation of new ventures? Prior research suggests entrepreneurial behavior has multiple causes. Nurture explanations; often couched in terms of sociological theories like social learning have been popular. Aspects of nascent entrepreneurs' social contexts, notably their family business background, have been associated with new venture creation. But nature also appears to play a role. Other research has linked heritable biological factors, including testosterone, with the career choice to launch a new venture. This study presents theory and evidence linking the combination of both sociological and biological factors with new venture creation: a biosocial model of entrepreneurship. Empirical results indicate new venture creation is more likely among those individuals having a higher testosterone level in combination with a family business background. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
135.
Agricultural pharmaceuticals are a major environmental concern because of their hazardous effects on human and wildlife. This study analyzed phospholipid ester-linked fatty acids (PLFAs) and quinones to investigate the effects of a steroid (17beta-estradiol) and agricultural antibiotics (chlortetracycline and tylosin) on soil microbes in the laboratory. Two different types of soil were used: Sequatchie loam (0.8% organic matter) and LaDelle silt loam (9.2% organic matter). The soils were spiked with 17beta-estradiol and antibiotics, alone or in combination. In Sequatchie loam, 17beta-estradiol significantly increased the microbial biomass, especially the biomarkers for beta proteobacteria (16:1omega7c, 18:1omega7c, Cy17:0, and UQ-8). The coexistence of antibiotics decreased the stimulatory effect of 17beta-estradiol on the microbial community. In LaDelle silt loam, there were no significant differences in total microbial biomass and their microbial community structure among the treatments. Overall, 17beta-estradiol changed the microbial community of soil and the presence of antibiotics nullified the effect of 17beta-estradiol. However, the effects of 17beta-estradiol and antibiotics on soil microbes were sensitive to the soil properties, as seen in the LaDelle silt loam.  相似文献   
136.
Experiments were conducted to assess the bioavailability of polyclycic aromatic hydrocarbons (PAHs) in soil from a Manufactured Gas Plant site. Three plant species were cultivated for four consecutive growing cycles (28 days each) in soil contaminated with 36.3 microg/g total PAH. During the first growth period, Cucurbita pepo ssp. pepo (zucchini) tissues contained significantly greater quantities of PAHs than did Cucumis sativus (cucumber) and Cucurbita pepo ssp. ovifera (squash). During the first growth cycle, zucchini plants accumulated up to 5.47 times more total PAH than did the other plants, including up to three orders of magnitude greater levels of the six ring PAHs. Over growth cycles 2-4, PAH accumulation by zucchini decreased by 85%, whereas the uptake of the contaminants by cucumber and squash remained relatively constant. Over all four growth cycles, the removal of PAHs by zucchini was still twice that of the other species. Two earthworm species accumulated significantly different amounts of PAH from the soil; Eisenia foetida and Lumbricus terrestris contained 0.204 and 0.084 microg/g total PAH, respectively, but neither species accumulated measurable quantities 5 or 6 ring PAHs. Lastly, in abiotic desorption experiments with an aqueous phase of synthetically prepared organic acid solutions, the release of 3 and 4 ring PAHs from soil was unaffected by the treatments but the desorption of 5-6 ring constituents was increased by up to two orders of magnitude. The data show that not only is the accumulation of weathered PAHs species-specific but also that the bioavailability of individual PAH constituents is highly variable.  相似文献   
137.
138.
Sampling of the Afon Goch over a 14-month period revealed maximum dissolved Fe, Al, Mn, Cu and Zn concentrations of 259, 167, 49, 60 and 42 mg dm(-3), respectively, and pH as low as 2.3, making it one of the most metal- and acid-contaminated streams in the UK. The river produces particulates by precipitation of ferrihydrite, due to the entry of near-neutral tributary waters, under all discharge conditions. Consequently, metal transport in this stream is dominated by processes different from those in less contaminated streams. The stream acts as a sink for contaminants, except under high discharge, when accumulated metals are flushed from the system. The implications of these observations for the monitoring and management of streams polluted by acid mine drainage are discussed.  相似文献   
139.
Recurring disagreements during national preparations to reduce emissions from deforestation and forest degradation (REDD+) are contributing to policy reform at multiple scales. The objectives of this study are to (i) develop a general framework to characterise diverse stakeholder perspectives on REDD+ programme objectives and governance arrangements, and (ii) apply this framework to analyse key stakeholders involved in REDD+ readiness process of Peru: the Inter-ethnic Association for the Development of the Peruvian Rainforest (Asociación Interétnica de Desarrollo de la Selva Peruana, AIDESEP), the Peruvian government and the World Bank. As indigenous peoples strive to maintain their own traditions and priorities, a turbulent readiness process is helping to resolve long-ignored issues of indigenous rights and to make REDD+ programme governance structures more inclusive. The Peruvian government/World Bank approach to REDD+ is incompatible with that of AIDESEP, therefore parallel implementation will be required for them to co-exist. Although a diversity of participants has helped to check and balance the centralization of decision-making power over REDD+ programme development, a history of failed assurances and agreements point to a need to maintain vigilance as new laws, regulations and safeguards are implemented.  相似文献   
140.
Klinefelter syndrome (KS) or 47,XXY is the most common sex chromosome aneuploidy (SCA), occurring at a prevalence of 1 in 600 male pregnancies. Historically, only 25% of individuals with KS came to medical attention, for a range of issues across the life course including under-virilisation at birth, developmental and social concerns in childhood, absence, delay or arrest of puberty in adolescence or infertility in adulthood. Our understanding of the phenotypic spectrum of KS has been largely influenced by this ascertainment bias. With increasing uptake of antenatal noninvasive prenatal testing (NIPT), a corresponding increase in identification of KS has been documented. Population-based longitudinal data from infancy to adulthood on these individuals is lacking, which impedes balanced antenatal genetic counselling and raises issues for prospective parents and clinicians alike.  相似文献   
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