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31.
Drawing from social/political influence, leader–member exchange (LMX), and social comparison theories, the present two‐study investigation examines three levels of LMX differentiation (i.e., individual‐level, meso‐level, and group‐level LMX differentiation) and further tests a model of the joint effects of political skill and LMX differentiation on LMX, relative LMX, and employee work outcomes. In Study 1, we used data from 231 employees and found support for the interactive effect of political skill and individual perceptions of LMX differentiation on LMX quality. We also found partial support for the moderating role of individual‐level LMX differentiation on the indirect effects of political skill on self‐rated task performance and job satisfaction via LMX. In Study 2, we used data from 185 supervisor–subordinate dyads and examined both meso‐level and group‐level LMX differentiation via a multilevel moderated mediation model. Results supported the moderating role of group‐level LMX differentiation and group mean LMX on the indirect effects of political skill on supervisor‐rated task performance and contextual performance/citizenship behavior as well as job satisfaction via relative LMX. Overall, the results suggest that politically skilled employees reap the benefits of LMX differentiation, as they enjoy higher absolute LMX and relative (i.e., to their peers) LMX quality. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Over 40 years, the detrital aquifer of the Plana de Castellón (Spanish Mediterranean coast) has been subjected to seawater intrusion because of long dry periods combined with intensive groundwater exploitation. Against this backdrop, a managed artificial recharge (MAR) scheme was implemented to improve the groundwater quality. The large difference between the electrical conductivity (EC) of the ambient groundwater (brackish water due to marine intrusion) and the recharge water (freshwater) meant that there was a strong contrast between the resistivities of the brackish water saturated zone and the freshwater saturated zone. Electrical resistivity tomography (ERT) can be used for surveying similar settings to evaluate the effectiveness of artificial recharge schemes. By integrating geophysical data with lithological information, EC logs from boreholes, and hydrochemical data, we can interpret electrical resistivity (ER) with groundwater EC values and so identify freshwater saturated zones. Using this approach, ERT images provided a high-resolution spatial characterization and an accurate picture of the shape and extent of the recharge plume of the MAR site. After 5 months of injection, a freshwater plume with an EC of 400–600 μS/cm had formed that extended 400 m in the W-E direction, 250 m in the N-S direction, and to a depth of 40 m below piezometric level. This study also provides correlations between ER values with different lithologies and groundwater EC values that can be used to support other studies.  相似文献   
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We explored the at-sea behavior and marine habitat use of the Southern Giant Petrel breeding in Patagonia, Argentina by means of satellite telemetry. Adult breeders showed a wide distribution over the Patagonian Shelf, using 74% of its surface. The maximum distance traveled from the colonies was 683 km, but on average birds moved no more than 200 km further away from their colony. Important marine areas were located in the shelf break, middle shelf and coastal waters. Areas of activity by sex overlap between 35 and 94%. Females foraged primarily away from the coast and males mainly on coastal areas. Both sexes were capable of flying up to 4,000 km but most of the foraging trips were of less than 200 km. Our results emphasize the importance of the Patagonian Shelf as foraging habitat for pelagic seabirds and contribute to international efforts to identify and protect a network of marine sites.  相似文献   
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Humic acids (HAs) from three soils of different origin (Chernozem, Ferralsol and Ranker) have been fractionated by coupling size exclusion chromatography (SEC) and polyacrylamide gel electrophoresis (PAGE) on three fractions (fractions A, B, C + D) with different molecular sizes (MSs) and exactly defined electrophoretic mobility (EM). Fractions identically marked had similar EM and MS, independently of HA sources. The photoinductive properties of the whole HAs and their fractions were compared by studying the photoinduced transformation of fenuron at 365 nm. High MS fractions A and B appeared to exhibit poor photoinductive activities compared to the whole HAs, whereas low MS fraction C + D in Chernozem and Ranker were more efficient than the whole HAs. A fourth intermediary fraction containing a mixture of fractions B and C + D with small amount of D was shown to photoinduce poorly the transformation of fenuron. It was therefore concluded that the molecules capable of photoinducing the transformation of fenuron were mainly contained in fraction D. Fluorescence properties of Chernozem HA and its fractions have been tested. Fraction C + D exhibited a very similar fluorescence emission spectrum in comparison with the whole HA and in contrast, the fractions A and B emitted very weakly.  相似文献   
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Ploidy or genome-wide chromosomal anomalies such as triploidy, diploid/triploid mixoploidy, chimerism, and genome-wide uniparental disomy are the cause of molar pregnancies, embryonic lethality, and developmental disorders. While triploidy and genome-wide uniparental disomy can be ascribed to fertilization or meiotic errors, the mechanisms causing mixoploidy and chimerism remain shrouded in mystery. Different models have been proposed, but all remain hypothetical and controversial, are deduced from the developmental persistent genomic constitutions present in the sample studied and lack direct evidence. New single-cell genomic methodologies, such as single-cell genome-wide haplotyping, provide an extended view of the constitution of normal and abnormal embryos and have further pinpointed the existence of mixoploidy in cleavage-stage embryos. Based on those recent findings, we suggest that genome-wide anomalies, which persist in fetuses and patients, can for a large majority be explained by a noncanonical first zygotic cleavage event, during which maternal and paternal genomes in a single zygote, segregate to different blastomeres. This process, termed heterogoneic division, provides an overarching theoretical basis for the different presentations of mixoploidy and chimerism.  相似文献   
38.
Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.  相似文献   
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Lake Baikal is the deepest and oldest freshwater lake in the world containing about 20% of the world's fresh water. The present state of its contamination with organic pollutants was studied during 1997–1998 by collecting samples of sediments, phytoplankton, Zooplankton, sponges, aquatic plants, algae, muscles of various fish species, eggs of various birds and blubber of seals. Samples were prepared and analysed using GC‐MS for semivolatile priority pollutants on the US EPA list, for the presence of organochlorine pesticides and for PCBs. The results showed that there was pronounced bioaccumulation of persistent organochlorine compounds along the trophic chain, leading to substantial residues of organochlorine compounds in seals (e.g. 0.87–25.3 ppm of p,p'‐DDT in blubber).  相似文献   
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