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The proper management of an ecological population is greatly aided by solid information about its species' abundances. For the general heterogeneous Poisson species abundance setting, we develop the non-parametric mle for the entire probability model, namely for the total number N of species and the generating distribution F for the expected values of the species' abundances. Solid estimation of the entire probability model allows us to develop generator-based measures of ecological diversity and evenness which have inferences over similar regions. Also, our methods produce a solid goodness-of-fit test for our model as well as a likelihood ratio test to examine if there is heterogeneity in the expected values of the species' abundances. These estimates and tests are examined, in detail, in the paper. In particular, we apply our methods to important data from the National Breeding Bird Survey and discuss how our methods can also be easily applied to sweep net sampling data. To further examine our methods, we provide simulations for several illustrative situations.  相似文献   
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During the last decade, many studies have focused on the detrimental effects of noise pollution on acoustic communication. Surprisingly, although it is known that noise exposure strongly influences health in humans, studies on wildlife remain scarce. In order to gain insight into the consequences of traffic noise exposure, we experimentally manipulated traffic noise exposure as well as the endocrine status of animals to investigate physiological and phenotypic consequences of noise pollution in an anuran species. We showed that noise exposure increased stress hormone level and induced an immunosuppressive effect. In addition, both traffic noise exposure and stress hormone application negatively impacted H. arborea vocal sac coloration. Moreover, our results suggest profound changes in sexual selection processes because the best quality males with initial attractive vocal sac coloration were the most impacted by noise. Hence, our study suggests that the recent increases in anthropogenic noise worldwide might affect a broader range of animal species than previously thought, because of alteration of visual signals and immunity. Generalizing these results to other taxa is crucial for the conservation of biodiversity in an increasingly noisy world.  相似文献   
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The 49,XXXXY syndrome is a rare sex chromosome anomaly with an approximate incidence of 1 in 85 000 male live births. The diagnosis is usually ascertained postnatally by the association of mental retardation, variable growth deficiency, Down syndrome-like facial dysmorphy, hypogenitalism and other malformations, especially involving the heart and skeleton. Prenatal diagnosis of the pentasomy 49,XXXXY is generally fortuitous and sonographic features have rarely been described in the literature. We report here on two cases of 49,XXXXY syndrome diagnosed prenatally because of sonographic abnormalities. In the first, amniocentesis was performed at 26 weeks' gestation for polyhydramnios, unilateral clubfoot and micropenis. In the second, a karyotype was carried out on chorionic villi at 13 weeks' gestation for cystic hygroma. These observations and the six previously reported cases demonstrate that cystic hygroma in first or second trimester of pregnancy may be associated with sex chromosome aneuploidy other than Turner syndrome. Moreover, they emphasize the importance of detailed sonographic examination in the second trimester, as small penis and abnormal posturing of the lower extremities are very suggestive of the 49,XXXXY syndrome. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Food and Environmental Virology - Outside the host, viruses will eventually lose their ability to infect cells due to conformational changes that occur to proteins on the viral capsid. In order to...  相似文献   
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With cities facing climate change, climate adaptation is necessary to reduce risks such as heat stress and flooding and maintain the goals of sustainable urban development. In climate change literature, the focus has been on developing a new dedicated policy domain for climate adaptation. Yet, empirical evidence shows that in practice actors are searching for solutions that not only serve climate adaptation, but integrate the adaptation objective in existing policy domains (e.g., urban planning, water management, public health). The integration of adaptation in other policy domains, also called “mainstreaming climate adaptation,” can stimulate the effectiveness of policy making through combining objectives, increase efficient use of human and financial resources and ensure long-term sustainable investments. A better understanding of the process of mainstreaming is, however, lacking. The article introduces a conceptual model for mainstreaming climate adaptation to enhance our understanding of the concept as well as the barriers and opportunities that influence these integration processes and to explore strategies for overcoming barriers and creating opportunities. Two Dutch case studies—related to urban planning—are used to illustrate the value of the model. The cases demonstrate the dynamic process of mainstreaming and raise discussion of the appropriate criteria for evaluating mainstreaming in relation to the aims of climate adaptation. The paper concludes with an exploration of specific strategies to facilitate the mainstreaming of adaptation in existing and new policy domains.  相似文献   
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Three years of field data, classical linear reservoir theory, and a new dissolution model confirm the hypothesis that residual chloride from highway deicing applications dissolves into precipitation throughout the year. The measured input includes 52 storm hyetographs and logs of salt and premix applications on an access road with a closed drainage system subject to runoff, interflow, and baseflow. The output data feature discharge and conductivity in an outlet weir measured continuously from February 1998 to May 2000. Individual storm hydrographs and pollutographs yield calibrated first flush dissolved chloride concentrations and residual solid chloride loads that persist at appreciable levels over the entire period of record. The storm calibrations imply a source strength w of 2.01 x 10(-6) s(-1) that accurately models chloride dissolution kinetics through three salt seasons on the access road. This w rests on physically plausible values for the depression storage depth zeta (3 mm) and porosity n (0.40) that store the residual chloride.  相似文献   
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