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31.
Birds have been comprehensively assessed on the International Union for Conservation of Nature (IUCN) Red List more times than any other taxonomic group. However, to date, generation lengths have not been systematically estimated to scale population trends when undertaking assessments, as required by the criteria of the IUCN Red List. We compiled information from major databases of published life-history and trait data for all birds and imputed missing life-history data as a function of species traits with generalized linear mixed models. Generation lengths were derived for all species, based on our modeled values of age at first breeding, maximum longevity, and annual adult survival. The resulting generation lengths varied from 1.42 to 27.87 years (median 2.99). Most species (61%) had generation lengths <3.33 years, meaning that the period of 3 generations—over which population declines are assessed under criterion A—was <10 years, which is the value used for IUCN Red List assessments of species with short generation times. For these species, our trait-informed estimates of generation length suggested that 10 years is a robust precautionary value for threat assessment. In other cases, however, for whole families, genera, or individual species, generation length had a substantial impact on their estimated extinction risk, resulting in higher extinction risk in long-lived species than in short-lived species. Although our approach effectively addressed data gaps, generation lengths for some species may have been underestimated due to a paucity of life-history data. Overall, our results will strengthen future extinction-risk assessments and augment key databases of avian life-history and trait data.  相似文献   
32.
The complexity of municipal waste management decision-making has increased in recent years, accompanied by growing scrutiny from stakeholders, including local communities. This complexity reflects a socio-technical framing of the risks and social impacts associated with selecting technologies and sites for waste treatment and disposal facilities. Consequently there is growing pressure on local authorities for stakeholders (including communities) to be given an early opportunity to shape local waste policy in order to encourage swift planning, development and acceptance of the technologies needed to meet statutory targets to divert waste from landfill. This paper presents findings from a research project that explored the use of analytical–deliberative processes as a legitimising tool for waste management decision-making. Adopting a mixed methods approach, the study revealed that communicating the practical benefits of more inclusive forms of engagement is proving difficult even though planning and policy delays are hindering development and implementation of waste management infrastructure. Adopting analytical–deliberative processes at a more strategic level will require local authorities and practitioners to demonstrate how expert-citizen deliberations may foster progress in resolving controversial issues, through change in individuals, communities and institutions. The findings suggest that a significant shift in culture will be necessary for local authorities to realise the potential of more inclusive decision processes. This calls for political actors and civic society to collaborate in institutionalising public involvement in both strategic and local planning structures.  相似文献   
33.
Thriving is defined as the psychological state in which individuals experience both a sense of vitality and learning. We developed and validated a measure of the construct of thriving at work. Additionally, we theoretically refined the construct by linking it to key outcomes, such as job performance, and by examining its contextual embeddedness. In Study 1, we conducted second‐order confirmatory factor analyses in two samples, demonstrating initial support for the two‐dimensional structure of thriving. We provided evidence for the convergent and discriminant validity of thriving in relation to theoretically related constructs, such as positive and negative affects, learning and performance goal orientations, proactive personality, and core self‐evaluations. In Study 2, across two different samples, we further assessed construct validity by establishing a relationship between thriving and career development initiative, burnout, health, and individual job performance, explaining significant variance beyond traditional attitudinal predictors, such as job satisfaction and organizational commitment. Finally, in Study 3, we focused on understanding the contextual embeddedness of thriving. We found differences in reports of thriving across two points in time, when substantial changes are occurring in peoples' work lives and across contexts (i.e., work and non‐work). Implications for theory and practice, as well as directions for future research, are discussed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
34.
Populations living in the Southwest United States are more likely to be exposed to elevated drinking water arsenic levels compared to other areas of the country. Skin changes, including hyperpigmentation and generalized hyperkeratosis, are the most common signs of chronic arsenic ingestion from drinking water. The purpose of this study was to determine the feasibility of using dermatology practices in New Mexico, Arizona, and western Texas as a surveillance system for arsenical skin disorders related to drinking water. Postcard questionnaires were mailed to practicing dermatologists. The number of cases of arsenical hyperpigmentation/keratoses seen by these dermatologists during the past 10 years and the past year were estimated. Of 240 dermatologists who were mailed questionnaires, 37 reported seeing 237 patients with arsenical hyperpigmentation/keratoses in the past 10 years and 35 patients in the past year. Since approximately one-eighth of dermatologists practicing in the Southwest saw at least one patient with arsenical hyperpigmentation/keratoses during one year, it appears feasible to complete a population-based study of these conditions.  相似文献   
35.
The separate effects of 50% increases in the prices of energy, renewable and nonrenewable natural resource inputs on factor demands and production costs are simulated for Canadian total manufacturing and six two-digit industries. Both renewable and nonrenewable natural resource price increases have a substantially greater effect upon the demands for other factors and upon production costs than a parallel energy price increase. These results are important from a policy perspective and justify the further disaggregation of inputs in this and in other models of input demand.  相似文献   
36.
37.
Fetal skin biopsy at 20 weeks' gestation in a woman at risk for a child with the lethal skin-blistering disorder junctional epidermolysis bullosa (Herlitz) confirmed an affected fetus. Genomic DNA from the aborted fetus was examined for mutations in laminin 5, a macromolecule involved in adhesion at the dermal-epidermal junction, and a candidate protein in this condition. Polymerase chain reaction (PCR) amplification of exon 10 and parts of the flanking introns of the gene encoding the β3 chain of laminin 5 (LAMB3) and subsequent analysis by agarose gel electrophoresis showed a more slowly migrating band in the affected fetus compared with the normal control. Nucleotide sequencing of the abnormal PCR product revealed a homozygous 77 bp duplication within the exon, resulting in a premature termination codon 250 bp downstream from the 3′ end of the duplication. Maternal DNA was heterozygous for the mutant and wild-type alleles. These findings illustrate the genetic basis of the skin disease in this case and also offer the prospects of a simple, rapid, and reliable first-trimester DNA-based prenatal, or even preimplantation, diagnostic test for future pregnancies in this family.  相似文献   
38.
Streams alter the concentration of nutrients they transport and thereby influence nutrient loading to estuaries downstream; however, the relationship between in-stream uptake, discharge variability, and subsequent nutrient export is poorly understood. In this study, in-stream N and P uptake were examined in the stream network draining a row-crop agricultural operation in coastal North Carolina. The effect of in-stream nutrient uptake on estuarine loading was examined using continuous measurements of watershed nutrient export. From August to December 2003, 52 and 83% of the NH4+ and PO4(3-) loads were exported during storms while concurrent storm flow volume was 34% of the total. Whole-ecosystem mass transfer velocities (Vf) of NH4+ and PO4(3-), measured using short-term additions of inorganic nutrients, ranged from 0.1 to 25 mm min(-1). Using a mass balance approach, this in-stream uptake was found to attenuate 65 to 98% of the NH4+ flux and 78 to 98% of the PO4(3-) flux in small, first-order drainage ditches. For the larger channel downstream, an empirical model based on Vf and discharge was developed to estimate the percentage of the nutrient load retained in-stream. The model predicted that all of the upstream NH4+ and PO4(3-) load was retained during base flow, while 65 and 37% of the NH4+ and PO4(3-) load was retained during storms. Remineralization from the streambed (vs. terrestrial sources) was the apparent source of NH4+ and PO4(3-) to the estuary during base flow. In-stream uptake reduced the dissolved inorganic N to dissolved inorganic P ratio of water exported to the N-limited estuary, thus limiting the potential for estuarine phytoplankton growth.  相似文献   
39.
Aquatic total phosphorus (Tot-P) is measured at fish-cages in Lake Huron for environmental regulatory compliance. An improved understanding of how Tot-P is manifested in the near-field (相似文献   
40.
Formal engagement of indigenous peoples in conservation is increasing globally and leads to multiple benefits to communities while contributing to national and international biodiversity goals and obligations. This and ongoing declines in biodiversity have led to calls to increase opportunities for indigenous people to engage in managing their estates. However, there is no overarching understanding of indigenous peoples’ involvement in conservation, which limits the identification of new opportunities. We amalgamated information across governments and large nongovernmental organizations in the megadiverse country of Australia to quantify the involvement of indigenous people in management of threatened species. We identified 153 Australian‐based projects undertaken by different indigenous groups around the nation in 2015 and 2016 that included explicit funds for management of threatened species or threatened ecosystems. Most were in remote parts of western and northern Australia. Almost one‐quarter of all threatened animals and 2% of threatened plants were the subject of some formal conservation action by indigenous people. Occurrence records for 1574 threatened species showed that 823 (89.2%) of 923 species recorded on indigenous peoples’ lands were not listed in management projects. This gap may represent new opportunities for conservation initiatives. Because at least 59.5% of Australia's threatened species occur on indigenous peoples’ lands, efforts to build appropriate and effective indigenous conservation alliances are vital. However, it is also important to recognize that threatened species are part of complex social, ecological, economic and cultural systems, and to achieve successful outcomes requires consideration of indigenous peoples’ priorities, rights, and obligations and relationships with their traditionally owned land and sea.  相似文献   
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