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121.
This research studied possible benefits of indoor plants on attention capacity in a controlled laboratory experiment. Participants were 34 students randomly assigned to one of two conditions: an office setting with four indoor plants, both flowering and foliage, or the same setting without plants. Attention capacity was assessed three times, i.e. immediately after entering the laboratory, after performing a demanding cognitive task, and after a five-minute break. Attention capacity was measured using a reading span test, a dual processing task known to tap the central executive function of attention. Participants in the plant condition improved their performance from time one to two, whereas this was not the case in the no-plant condition. Neither group improved performance from time two to three. The results are discussed in the context of Attention Restoration Theory and alternative explanations.  相似文献   
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An ecotoxicological screening of environmental samples collected in the vicinity of rice fields followed a combination of physical and chemical measurements and chronic bioassays with two freshwater trophic levels (microalgae: Pseudokirchneriella subcapitata and Chlorella vulgaris; daphnids: Daphnia longispina and Daphnia magna). As so, water and sediment/soil elutriate samples were obtained from three sites: (1) in a canal reach crossing a protected wetland upstream, (2) in a canal reach surrounded by rice fields and (3) in a rice paddy. The sampling was performed before and during the rice culture. During the rice cropping, the whole system quality decreased comparatively to the situation before that period (e.g. nutrient overload, the presence of pesticides in elutriates from sites L2 and L3). This was reinforced by a significant inhibition of both microalgae growth, especially under elutriates. Contrary, the life-history traits of daphnids were significantly stimulated with increasing concentrations of water and elutriates, for both sampling periods.  相似文献   
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ProblemMotor-vehicle crashes are a leading cause of death in the United States. Seatbelts are highly effective in preventing serious injury and death in the event of a crash. Not all states have primary enforcement of seatbelt laws.MethodsData from the 2002, 2006, 2008, and 2010 Behavioral Risk Factor Surveillance System were used to calculate prevalence of seatbelt use by state and type of state seatbelt law (primary vs. secondary enforcement).Results and discussionSelf-reported seatbelt use among adults in the United States increased steadily between 2002 and 2010, with the national prevalence reaching 87% in 2010. Overall, seatbelt use in 2010 was 9 percentage points higher in the states with primary enforcement laws than in the states with secondary enforcement laws (89% vs. 80%). Impact on industry: Primary enforcement seatbelt laws and enhanced enforcement of seatbelt laws are proven strategies for increasing seatbelt use and reducing traffic fatalities.  相似文献   
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Mesozooplankton communities in the meso-oligotrophic Gulf of Aqaba, Northern Red Sea, were investigated over a 2 years period (2005–2007) with emphasis on the trophodynamic relations among different taxonomic groups ranging from primary consumers to carnivorous predators. Based on stable isotope analyses, we present evidence for a strong contribution of ‘new’ nitrogen mainly derived from the utilization of aerosol nitrate by unicellular cyanobacteria especially during summer stratification and the propagation of exceptionally low δ15N onto higher trophic levels. In contrast, N2-fixation by diazotrophs seemed to play a minor role, while the utilization of deep water nitrate by cyanobacteria and eukaryotic algae might be of importance during winter mixing. Based on 15N enrichment of consumers, clear differences between exclusively herbivorous organisms (doliolids, appendicularians, pteropods) and those with omnivorous feeding modes were detected. The category of omnivores comprised a large variety of taxons ranging from small meroplanktonic larvae to non-calanoid copepods (harpacticoids, cyclopoids and poecilostomatoids) that together form a diverse and complex community with overlapping feeding modes. In addition, distinct seasonality patterns in δ15N of copepods were found showing elevated trophic positions during periods of winter mixing, which were most pronounced for non-calanoid copepods. In general, feeding modes of omnivores appeared rather unselective, and relative contributions of heterotrophic protists and degraded material to the diets of non-calanoid copepods are discussed. At elevated trophic positions, four groups of carnivore predators were identified, while calanoid copepods and meroplanktonic predators showing lowest 15N enrichment within the carnivores. The direct link between ‘new’ nitrogen utilization by primary producers and the 15N enrichment of consumers in the planktonic food web of the Gulf of Aqaba emphasizes the significant contribution of ‘new’ nitrogen to the nitrogen budget and ecosystem functions in subtropical and tropical oligotrophic oceans.  相似文献   
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PCDD/F congener profiles have been used to determine the source of elevated TEQ concentrations in cows' milk collected in the vicinity of several industrial sites. Principal components analysis and modelling of the air-to-milk transfer of individual PCDD/F congeners have shown that the milk fingerprint was related to that of sediment taken from the River Rother adjacent to the farm where the cows had grazed. It is suggested that sediment from the river had been washed onto the grazing land during periods of flooding, and this had been ingested by the grazing cows. This pathway could represent an important route of contaminant intake for livestock grazing on the regularly inundated floodplains of rivers containing contaminated sediments.  相似文献   
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Despite increasing interest in the occurrence of Polybrominated diphenyl ethers (PBDEs) in the environment, there has been only limited effort expended to identify principal source input reservoirs and pathways into the environment. Taking a single congener BDE-47, an important component of the penta commercial product, we have estimated principal contemporary reservoirs and emissions in two regions with very different historical use patterns. In North America, production and use of the penta-product has been rising steadily for the last 20 years, whilst in the UK, use has been restricted over the last 10 years, and most recently, there has been an EU ban on use. Mass balance models have been applied using our contemporary emission estimates to predict environmental levels. Results highlight that contemporary emissions to air can account for contemporary air concentrations but cannot account for measured concentrations in principal reservoirs such as soils and sediments. Future efforts are needed to improve our knowledge of the stocks of PBDEs in use, and emission factors from those stocks, to better understand/predict past and likely future trends.  相似文献   
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