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141.
Grapsoid crabs of the genera Planes and Plagusia are commonly referred to as “rafting crabs” due to their propensity to live on flotsam and pelagic marine animals. Planes minutus and Planes major (=Planes cyaneus) are epibionts of sea turtles. Occurrences of grapsoid crabs in the genera Planes and Plagusia were evaluated on a total of 27 olive ridley sea turtles, Lepidochelys olivacea, from the eastern tropic Pacific (1998–2001) and the Hawaiian Islands (2002) captured in July–December each year. This is the first report of Planes marinus and Plagusia squamosa on sea turtles, and of P. major, P. marinus, and P. squamosa in sympatry on a confined substrate. Stomach content analyses showed P. major and P. marinus consumed a variety of neuston and marine vegetation, with the former consuming considerably more animal material. Epibiotic P. squamosa consumed mostly plant material. The three Planes species had distinctive differences in gastric mill tooth morphology. The versatile mouthparts of P. marinus are described and resemble those of their congeners. Most female P. major and P. marinus collected were ovigerous and present in all survey months.  相似文献   
142.
本文笔者通过回顾历史上优秀的师德观,明确加强新时期师德建设的意义;分析现阶段师德面临的新问题,探讨应如何正视和解决这些问题,以加强新时期师德建设。  相似文献   
143.
The field site network (FSN) plays a central role in conducting joint research within all Assessing Large-scale Risks for biodiversity with tested Methods (ALARM) modules and provides a mechanism for integrating research on different topics in ALARM on the same site for measuring multiple impacts on biodiversity. The network covers most European climates and biogeographic regions, from Mediterranean through central European and boreal to subarctic. The project links databases with the European-wide field site network FSN, including geographic information system (GIS)-based information to characterise the test location for ALARM researchers for joint on-site research. Maps are provided in a standardised way and merged with other site-specific information. The application of GIS for these field sites and the information management promotes the use of the FSN for research and to disseminate the results. We conclude that ALARM FSN sites together with other research sites in Europe jointly could be used as a future backbone for research proposals.  相似文献   
144.
Overharvesting of terrestrial and marine resources may be alleviated by encouraging an alternative configuration of livelihoods, particularly in rural communities in developing countries. Typical occupations in such areas include fishing and farming, and rural households often switch livelihood activities to suit climate and economic conditions. We used a machine-learning tool, deep-belief networks (DBN), and data from surveys of a rural Philippine coastal community to examine household desire to change livelihood. This desire is affected by a variety of factors, such as income, family needs, and feelings of work satisfaction, that are interrelated in complex ways. In farming households, livelihood changes often occur to diversify resources, increase income, and lessen economic risk. The DBN, given its multilayer perceptron structure, has a capacity to model nonlinear relationships among factors while providing an acceptable degree of accuracy. Relative to a set of 34 features (e.g., education, boat ownership, and work satisfaction), we examined the binary response variables desire to change work or not to change work. The best network had a test set accuracy of 97.5%. Among the features, 7 significantly affected desire to shift work: ethnicity, work satisfaction, number of persons in a household in ill health, number of fighting cocks owned, fishing engagement, buy-and-sell revenue, and educational level. A cross-correlation matrix of these 7 features indicated households less inclined to change work were those engaged in fishing and retail buying and selling. For fishing, provision of economic and other incentives should be considered to encourage changing from this occupation to allow recovery of fishery resources.  相似文献   
145.
Over the past 5 decades, scientists have been documenting negative anthropogenic environmental change, expressing increasing alarm, and urging dramatic socioecological transformation in response. A host of international meetings have been held, but the erosion of biological diversity continues to accelerate. Why, then, has no effective political action been taken? We contend that part of the answer may lie in the anthropocentric ethical premises and moral rhetoric typically deployed in the cause of conservation. We further argue that it is essential to advance moral arguments for biodiversity conservation that are not just based on perceived human interests but on ecocentric values, namely, convictions that species and ecosystems have value and interests that should be respected regardless of whether they serve human needs and aspirations. A broader array of moral rationales for biodiversity conservation, we conclude, would be more likely to lead to effective plans, adopted and enforced by governments, designed to conserve biological diversity. A good place to start in this regard would be to explicitly incorporate ecocentric values into the recommendations that will be made at the conclusion of the 15th meeting of the parties to the Convention on Biological Diversity, scheduled to be held in October 2020.  相似文献   
146.
Use of fipronil {5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile CAS 120068–37-3} topical pet products on dogs and cats introduces low level residues into residences. Distribution and fate studies of fipronil on pets and in residences were performed to evaluate potential determinants of human exposure. Fipronil, desulfinyl fipronil, fipronil sulfone and fipronil sulfide were measured on hair clippings and brushed hair. The derivatives usually represented <10% of fipronil applied. Cotton gloves worn over impervious nitrile gloves, cotton cloths placed indoors in locations frequented by pets, and cotton socks worn by residents as direct dosimeters collected fipronil and its derivatives listed above in low amounts during 4-week study periods. Subsequent acid hydrolysis urine biomonitoring did not reveal significant excretion of biomarkers at ppb levels. The human exposure potential of fipronil is low relative to levels of health concern.  相似文献   
147.
This research explores the attitudes of children from different socioeconomic backgrounds toward consumption with the aim of establishing a framework for incorporating the subject of (responsible) consumption into the upper elementary school curriculum. This study draws upon the four-step methodological procedure, including consumption diaries, focus-group sessions, interviews, and concept mapping, conducted among 140 upper elementary school children in the Netherlands between September 2010 and January 2011. The consumption diaries, chronological documents recording purchase, use and waste of materials, were used both as analytical tools and the means to stimulate environmental awareness. Comparison of the clusters generated by concept mapping analysis shows that there are significant differences between attitudes of children from different socioeconomic backgrounds. While pupils from the “well-to-do” predominantly ethnically Dutch schools showed greater awareness of and concern about their own consumptive patterns, children from less economically advantaged and ethnically mixed schools demonstrated lower environmental awareness and concern. However, children from the disadvantaged schools demonstrated more pro-environmental consumptive behaviors associated with the money-saving activities.  相似文献   
148.
149.
The conversion of natural habitat to urban settlements is a primary driver of biodiversity loss, and species' persistence is threatened by the extent, location, and spatial pattern of development. Urban growth models are widely used to anticipate future development and to inform conservation management, but the source of spatial input to these models may contribute to uncertainty in their predictions. We compared two sources of historic urban maps, used as input for model calibration, to determine how differences in definition and scale of urban extent affect the resulting spatial predictions from a widely used urban growth model for San Diego County, CA under three conservation scenarios. The results showed that rate, extent, and spatial pattern of predicted urban development, and associated habitat loss, may vary substantially depending on the source of input data, regardless of how much land is excluded from development. Although the datasets we compared both represented urban land, different types of land use/land cover included in the definition of urban land and different minimum mapping units contributed to the discrepancies. Varying temporal resolution of the input datasets also contributed to differences in projected rates of development. Differential predicted impacts to vegetation types illustrate how the choice of spatial input data may lead to different conclusions relative to conservation. Although the study cannot reveal whether one dataset is better than another, modelers should carefully consider that geographical reality can be represented differently, and should carefully choose the definition and scale of their data to fit their research objectives.  相似文献   
150.
New highly fluorinated monodentate and bidentate phosphine oxide compounds of the type {CF(3)(CF(2))(n)CH(2)CH(2)}(3)PO (n = 5, 9) and [{CF(3)(CF(2))(5)CH(2)CH(2)}(2)P(O)CH(2)CH(2)P(O){CH(2)CH(2)(CF(2))(5)CF(3)}] have been prepared. Their ability to extract a number of metals and radionuclides from aqueous solutions into perfluorinated solvents has been established and the extractable species investigated. All extractants extract the metals As(V), Cd(II), Co(II), Cr(VI), Hg(II), Pb(II), and Sn(II) with >75% removal. In addition, the radioisotopes (90)Sr(II), (133)Ba(II), and U(VI) have been investigated, whilst (59)Fe(III) has been used to model the extraction of plutonium. (133)Ba(II) shows a high distribution ratio for monodentate phosphine oxides, whilst for UO(2)(2+) and (59)Fe(III) bidentate phosphine oxides are superior.  相似文献   
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