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121.
Antecedents and consequences of participating in a romantic relationship in the workplace are critically examined. These factors are derived from social-psychological theories of interpersonal attraction, romantic attraction, love, emotion, and social exchange, as well as from previous research addressing romance in the workplace. The antecedent factors explain the processes by which romantic relationships develop between two members of the same organization, and the consequent factors highlight both the beneficial and detrimental effects that such relationships have on the participants, coworkers, and the host organization. Based on these formation and impact factors, a conceptual model of workplace romance is developed along with a series of testable propositions in order to facilitate and direct future research on romantic organizational behavior.  相似文献   
122.
A response to the Nuffield Council on Bioethics Consultation from the Institute of Biology, the Association of Applied Biology, the British Crop Protection Council, the British Ecological Society, the British Electrophoresis Society, the British Grassland Society, and the Institute of Horticulture  相似文献   
123.
124.
Mussels from Mytilus edulis complex were used as biomonitors of the trace metals Fe, Mn, Pb, Zn, and Cu at 17 sampling sites to assess the relative bioavailability of metals in coastal waters around the European continent. Because accumulated metal concentrations in a given area can differ temporally, data were corrected for the effect of season before large-scale spatial comparisons were made. The highest concentration of Fe was noted in the North Sea and of Mn in the Baltic. Increased tissue concentrations of Pb were recorded in the mussels from the Bay of Biscay and the Baltic Sea. Low concentrations of metals were determined in the mussels from the Mediterranean Sea and the Northern Baltic. Relatively low geographic variations of Cu and Zn indicate that mussels are able to partially regulate accumulated body concentrations, which means Cu and Zn are, to some extent, independent of environmental concentrations.  相似文献   
125.
Pyrrolizidine alkaloids (PAs) and related N-oxides (PANOs) are secondary plant metabolites thought to be found in approximately 3% of the flowering plants worldwide and exhibiting hepatotoxic properties to humans. As a consequence, beehive products are prone to be contaminated with those compounds by bees foraging PA-producing plants. Downstream contamination can also occur through food items containing honey. Analytical methods based on UHPLC separation and MS/MS detection were developed with a focus on very low LOQs and validated for the analysis of 16 PAs and 14 PANOs in honey, honey-based candies and snacks, as well as beehive product–based food supplements. A maximum level of 182 ng/g of PAs was detected in a Mediterranean honey, and high levels of heliotrine-type compounds were reported for the first time. An extensive sampling of honeys harvested in Belgium was performed (N = 374), the concentration levels were more limited with a maximum of 60 ng/g, and the contamination pattern was dominated by senecionine-type PAs. The PA levels in honey-based candies and snacks were very low, with respective maxima of 7.61 ng/g and 0.36 ng/g. Seventy-five percent among the pre-dosed food supplements based on beehive products were contaminated, with a maximum of 43 ng/g. The highest level was detected in a bee-collected pollen sample (1672 ng/g). The analytical results were consistent with the previously reported data for beehive products and confirmed that PA/PANO contamination in these food commodities is recurrent.  相似文献   
126.
We compared the European and eastern Chinese waterbird assemblages and checked whether the effects of human disturbance could be detected in the assemblages’ composition. For the different Chinese provinces, we expected to find a negative effect of economic development on the mean bird species mass and on the proportion of bentivorous, piscivorous and insectivorous bird species. We also expected to find relatively fewer large species in the Chinese assemblage. Species rank–abundance curves were relatively similar, but China had significantly more species with smaller body masses. The China assemblage was characterized by relatively higher abundance of heavy-bodied species, contrary to our expectations. Mean bird body mass decreased in China with increasing disturbance and increasing gross domestic product (GDP). For coastal provinces in China the percentage of bentivorous, piscivorous and insectivorous bird species declined with increasing GDP, maybe through the increased use of pesticides or fertilizer.  相似文献   
127.
The dominant nitrogen (N) fluxes were simulated in a mountain forest ecosystem on dolomitic bedrock in the Austrian Alps. Based on an existing small-scale climate model the simulation encompassed the present situation and a 50-yr projection. The investigated scenarios were current climate, current N deposition (SC1) and future climate (+2.5 degrees C and +10% annual precipitation) with three levels of N deposition (SC2, 3, 4). The microbially mediated N transformation, including the emission of nitrogen oxides, was calculated with PnET-N-DNDC. Soil hydrology was calculated with HYDRUS and was used to estimate the leaching of nitrate. The expected change of the forest ecosystem due to changes of the climate and the N availability was simulated with PICUS. The incentive for the project was the fact that forests on dolomitic limestone stock on shallow Rendzic Leptosols that are rich in soil organic matter are considered highly sensitive to the expected environmental changes. The simulation results showed a strong effect due to increased temperatures and to elevated levels of N deposition. The outflux of N, both as nitrate (6-25kg Nha(-1)yr(-1)) and nitrogen oxides (1-2kg Nha(-1)yr(-1)), from the forest ecosystem are expected to increase. Temperature exerts a stronger effect on the N(2)O emission than the increased rate of N deposition. The main part of the N emission will occur as N(2) (15kg Nha(-1)yr(-1)). The total N loss is partially offset by increased rates of N uptake in the biomass due to an increase in forest productivity.  相似文献   
128.
Grippo  Mark A.  Hlohowskyj  Ihor  Fox  Laura  Herman  Brook  Pothoff  Johanna  Yoe  Charles  Hayse  John 《Environmental management》2017,59(1):154-173
Environmental Management - The U.S. Army Corps of Engineers is conducting the Great Lakes and Mississippi River Interbasin Study to identify the highest risk aquatic nuisance species currently...  相似文献   
129.
Abstract

The residues of disulfoton and permethrin in an organic soil and in vegetables grown in soil treated with a granular formulation of the pesticides were determined by gas chromatography. The residues were removed from soil or plant samples by successive extractions with acetone and hexane. Permethrin persisted in the soil for the initial 28 days and declined slowly during the rest of the season but disulfoton after persisting for one week at the applied concentration was degraded in the next two weeks. The insecticides did not translocate into the edible parts of the vegetables but were present in the root system of onion and lettuce. Carrot and lettuce yields were not significantly different from those of the controls but onion yields were substantially decreased by the use of per‐methrin.  相似文献   
130.
The overall resource requirements for the production of germanium wafers for III–V multi-junction solar cells applied in concentrator photovoltaics have been assessed based on up to date process information. By employing the cumulative energy demand (CED) method and the cumulative exergy extraction from the natural environment (CEENE) method the following resources have been included in the assessment: fossil resources, nuclear resources, renewable resources, land resources, atmospheric resources, metal resources, mineral resources and water resources. The CED has been determined as 216 MJ and the CEENE has been determined as 258 MJex. In addition partial energy and exergy payback times have been calculated for the base case, which entails the installation of the high concentration photovoltaics (HCPVs) in the Southwestern USA, resulting in payback times of around 4 days for the germanium wafer production. Due to applying concentration technology the germanium wafer accounts for only 3% of the overall resource consumption of an HCPV system. A scenario analysis on the electricity input to the wafer production and on the country of installation of the HCPV has been performed, showing the importance of these factors on the cumulative resource consumption of the wafer production and the partial payback times.  相似文献   
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