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This longitudinal study investigates whether the work environment in mid-career is comparable for men and women MBAs. No gender differences were found in early career. However by mid-career, women report less income, career satisfaction, and boss appreciation than men. Discrimination is also more prevalent for women.  相似文献   
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Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature (T), thermal conductivity (K), resistivity (R) and thermal di usivity (D) from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N2O concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with CO2 in 2004 while T correlated with both N2O (r = 0.76, p = 0.0001) and CO2 (r = 0.88, p = 0.0001) in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and di ering spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R o er a promise as potential controlling factors for greenhouse gases fluxes in this pasture.  相似文献   
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Eleven white-tailed sea eagles (WSEs) (Haliaeetus albicilla) collected in Finland between 1994 and 2001 were examined for their causes of death, including analyses of ubiquitous environmental contaminants and parasites. Four WSEs died due to electrocution. Two were lead poisoned and another had fragments of a lead bullet in its gizzard. An 11-year-old female drowned entangled in fishing gear, but also had mercury levels in its liver and kidneys known for detrimental physiological effects. One WSE was evidently killed by an intraspecific conflict, which was also assumed to be with another bird. The mortality factors of two WSEs could not be clarified, but one had a lead level of 4.604 microg g(-1) in its liver, indicating high lead exposure at a clinically relevant concentration. All organ levels of chlorinated pesticides, polychlorinated biphenyls, and cadmium were moderate and not harmful for birds of prey. Seven helminth species, but no ectoparasites or coccidians, were found in 8 of 10 WSEs investigated for parasites. The highest prevalence of 40% was found for the liver fluke Metorchis billis, but no severe parasitosis was diagnosed for the eagles. The two acanthocephalan species Corynosoma semerme and Polymorphus meyeri are both new records for WSEs.  相似文献   
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The seasonal dynamics of Daphnia populations vary regionally throughout the United States. Within the general pattern, Daphnia increase in abundance after the initiation of the spring algal bloom in all lakes, but their subsequent seasonal patterns differ in various climatic regions. Lakes in regions with cooler summers have large-bodied Daphnia populations that tend to persist throughout the summer, although the species dominance may shift. Regions with warmer summers tend to have large-bodied Daphnia populations that decline or are absent through much of the summer. Still warmer water bodies tend to have medium- to small-bodied species that are abundant during spring, but absent most of the summer. Many central Florida lakes lack Daphnia; if Daphnia species are present, they tend to be small-bodied. Daphnia abundance in these water bodies varies, but seems to be independent of temperature.If surface water (lake, pond) sampling is done in all regions during July and August, the impression will be that Daphnia are absent from large segments of the United States. This would be erroneous, because Daphnia are important earlier during the spring and early summer but are likely to be absent during midsummer in some U.S. regions. Year-to-year variation will be superimposed on this regional pattern. Because there are differences in the dates when spring and summer occur, it would be useful to have an index period that would standardize the start of the growing season. The use of the terrestrial onset of greenness, based on remote sensing of the Normalized Difference Vegetation Index, is suggested as a possible index set point.  相似文献   
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