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181.
Office employees spend a lot of time inside buildings, where the physical conditions influence their well-being and indirectly influence their employers' business performance. With data from a field study conducted in the Netherlands in April to May 2003, we used path analysis to further elucidate the relationship between personal (gender and seasonality of mood shifts), building (view type, view quality, window distance, and social density), and perceived environmental conditions (light quality, and office impression) and physical and psychological discomfort, sleep quality, and environmental utility. The results show that window views, which that are rated as being more attractive, are beneficial to building occupants by reducing discomfort. However, being close to a window and rating the lighting as being of lower quality can result in thermal and glare problems (environmental utility). Reduced discomfort at work can improve sleep quality, indicating that physical conditions at work influence home life.  相似文献   
182.
The reintroduction of large predators provides a framework to investigate responses by prey species to predators. Considerable research has been directed at the impact that reintroduced wolves (Canis lupus) have on cervids, and to a lesser degree, bovids, in northern temperate regions. Generally, these impacts alter feeding, activity, and ranging behavior, or combinations of these. However, there are few studies on the response of African bovids to reintroduced predators, and thus, there is limited data to compare responses by tropical and temperate ungulates to predator reintroductions. Using the reintroduction of lion (Panthera leo) into the Addo Elephant National Park (AENP) Main Camp Section, South Africa, we show that Cape buffalo (Syncerus caffer) responses differ from northern temperate ungulates. Following lion reintroduction, buffalo herds amalgamated into larger, more defendable units; this corresponded with an increase in the survival of juvenile buffalo. Current habitat preference of buffalo breeding herds is for open habitats, especially during the night and morning, when lion are active. The increase in group size and habitat preference countered initial high levels of predation on juvenile buffalo, resulting in a return in the proportion of juveniles in breeding herds to pre-lion levels. Our results show that buffalo responses to reintroduced large predators in southern Africa differ to those of northern temperate bovids or cervids in the face of wolf predation. We predict that the nature of the prey response to predator reintroduction is likely to reflect the trade-off between the predator selection and hunting strategy of predators against the life history and foraging strategies of each prey species.  相似文献   
183.
In the initial phase of a complex emergency, an immediate population size assessment method, based on area sampling, is vital to provide relief workers with a rapid population estimate in refugee camps. In the past decade, the method has been progressively improved; six examples are presented in this paper and questions raised about its statistical validity as well as important issues for further research. There are two stages. The first is to map the camp by registering all of its co-ordinates. In the second stage, the total camp population is estimated by counting the population living in a limited number of square blocks of known surface area, and by extrapolating average population calculated per block to the total camp surface. In six camps selected in Asia and Africa, between 1992 and 1994, population figures were estimated within one to two days. After measuring all external limits, surfaces were calculated and ranged between 121,300 and 2,770,000 square metres. In five camps, the mean average population per square was obtained using blocks 25 by 25 meters (625 m2), and for another camp with blocks 100 by 100 m2. In three camps, different population density zones were defined. Total camp populations obtained were 16,800 to 113,600. Although this method is a valuable public health tool in emergency situations, it has several limitations. Issues related to population density and number and size of blocks to be selected require further research for the method to be better validated.  相似文献   
184.
Ehrich  Dorothée  Schmidt  Niels M.  Gauthier  Gilles  Alisauskas  Ray  Angerbjörn  Anders  Clark  Karin  Ecke  Frauke  Eide  Nina E.  Framstad  Erik  Frandsen  Jay  Franke  Alastair  Gilg  Olivier  Giroux  Marie-Andrée  Henttonen  Heikki  Hörnfeldt  Birger  Ims  Rolf A.  Kataev  Gennadiy D.  Kharitonov  Sergey P.  Killengreen  Siw T.  Krebs  Charles J.  Lanctot  Richard B.  Lecomte  Nicolas  Menyushina  Irina E.  Morris  Douglas W.  Morrisson  Guy  Oksanen  Lauri  Oksanen  Tarja  Olofsson  Johan  Pokrovsky  Ivan G.  Popov  Igor Yu.  Reid  Donald  Roth  James D.  Saalfeld  Sarah T.  Samelius  Gustaf  Sittler  Benoit  Sleptsov  Sergey M.  Smith  Paul A.  Sokolov  Aleksandr A.  Sokolova  Natalya A.  Soloviev  Mikhail Y.  Solovyeva  Diana V. 《Ambio》2020,49(3):801-804
Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided...  相似文献   
185.
Urban tinkering     
Cities are currently experiencing serious, multifaceted impacts from global environmental change, especially climate change, and the degree to which they will need to cope with and adapt to such challenges will continue to increase. A complex systems approach inspired by evolutionary theory can inform strategies for policies and interventions to deal with growing urban vulnerabilities. Such an approach would guide the design of new (and redesign of existing) urban structures, while promoting innovative integration of grey, green and blue infrastructure in service of environmental and health objectives. Moreover, it would contribute to more flexible, effective policies for urban management and the use of urban space. Four decades ago, in a seminal paper in Science, the French evolutionary biologist and philosopher Francois Jacob noted that evolution differs significantly in its characteristic modes of action from processes that are designed and engineered de novo (Jacob in Science 196(4295):1161–1166, 1977). He labeled the evolutionary process “tinkering”, recognizing its foundation in the modification and molding of existing traits and forms, with occasional dramatic shifts in function in the context of changing conditions. This contrasts greatly with conventional engineering and design approaches that apply tailor-made materials and tools to achieve well-defined functions that are specified a priori. We here propose that urban tinkering is the application of evolutionary thinking to urban design, engineering, ecological restoration, management and governance. We define urban tinkering as:
A mode of operation, encompassing policy, planning and management processes, that seeks to transform the use of existing and design of new urban systems in ways that diversify their functions, anticipate new uses and enhance adaptability, to better meet the social, economic and ecological needs of cities under conditions of deep uncertainty about the future.
This approach has the potential to substantially complement and augment conventional urban development, replacing predictability, linearity and monofunctional design with anticipation of uncertainty and non-linearity and design for multiple, potentially shifting functions. Urban tinkering can function by promoting a diversity of small-scale urban experiments that, in aggregate, lead to large-scale often playful innovative solutions to the problems of sustainable development. Moreover, the tinkering approach is naturally suited to exploring multi-functional uses and approaches (e.g., bricolage) for new and existing urban structures and policies through collaborative engagement and analysis. It is thus well worth exploring as a means of delivering co-benefits for environment and human health and wellbeing. Indeed, urban tinkering has close ties to systems approaches, which often are recognized as critical to sustainable development. We believe this concept can help forge much-closer, much-needed ties among engineers, architects, evolutionary ecologists, health specialists, and numerous other urban stakeholders in developing innovative, widely beneficial solutions for society and contribute to successful implementation of SDG11 and the New Urban Agenda.
  相似文献   
186.
187.
The occurrence of current-use and banned pesticides is reported in wet-precipitation collected from four sites across Atlantic Canada during the period 1980-2000. The most frequently detected compounds were alpha-HCH, gamma-HCH (lindane), chlorothalonil, pentachlorophenol, atrazine, and endosulfan. Median site concentrations varied between not-detected and 10.2 ng l(-1). Deposition of HCHs (hexachlorocyclohexane), chlorothalonil, and endosulfan at Kejimkujik (Keji) and Jackson, Nova Scotia, were generally similar. Significant spatial differences (p<0.05), however, were found for the HCH isomers and endosulfan at Keji and Gros Morne (Newfoundland and Labrador), areas geographically separated by the northern Gulf of St. Lawrence. Long-term deposition of alpha-HCH decreased (p<0.05) at both Keji (1980-2000) and Gros Morne (1994-2000), with half-lives of 5.9 and 4.5 y, respectively. A decreasing trend was also found for pentachlorophenol with a half-life of 4.9 y at Jackson. Significant negative trends (p<0.05) were observed for alpha-/gamma-HCH ratios during the study at Keji and Jackson, possibly reflecting changes in production and use patterns of technical HCH and lindane on a continental and perhaps hemispheric scale. Seasonal trends for alpha-HCH and gamma-HCH were found to vary over the 20-y study period at Keji, however, spatial trends were generally similar between sites. Seasonal trends were observed with peak deposition generally occurring during the growing period (spring-summer) for the HCHs, chlorothalonil, endosulfan, and atrazine. Bimodal seasonal trends were also observed for these compounds with the exception of endosulfan.  相似文献   
188.
Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained a greater organic C content, while the slightly alkaline SAC soil favored hydrolysis. CL-20 degradation was accompanied by the formation of formate, glyoxal, nitrite, ammonium, and nitrous oxide. Biotic degradation of CL-20 occurred through the formation of its denitrohydrogenated derivative (m/z 393 Da) while hydrolysis occurred through the formation of a ring cleavage product (m/z 156 Da) that was tentatively identified as CH2N-C(N-NO2)-CHN-CHO or its isomer N(NO2)CH-CHN-CO-CHNH. Due to their chemical specificity, these two intermediates may be considered as markers of in situ attenuation of CL-20 in soil.  相似文献   
189.
In recent years, China and other emerging countries have been experiencing severe air pollution problems with high concentrations of atmospheric aerosol particles. Satellite measurements indicate that the aerosol loading of the atmosphere in highly populated regions of China is about 10 times higher than, for example, in Europe and in the Eastern United States. The exposure to extremely high aerosol concentrations might lead to important human health effects, including respiratory and cardiovascular diseases as well as lung cancers. Here, we analyze 52-year historical surface measurements of haze data in the Chinese city of Guangzhou, and show that the dramatic increase in the occurrence of air pollution events between 1954 and 2006 has been followed by a large enhancement in the incidence of lung cancer.  相似文献   
190.
Halogenated acetaldehydes: analysis, stability and fate in drinking water   总被引:1,自引:0,他引:1  
Koudjonou BK  LeBel GL 《Chemosphere》2006,64(5):795-802
In our previous studies, chloral hydrate has been the only chlorinated acetaldehyde determined in drinking water because authentic standards of other related haloacetaldehydes were not available. Recently, standards of dichloroacetaldehyde, bromochloroacetaldehyde, dibromoacetaldehyde, bromodichloroacetaldehyde, chlorodibromoacetaldehyde, and tribromoacetaldehyde have become available commercially. They were obtained and verified for purity and stability using a dual-column GC-ECD system. Each commercial standard was found to contain small amounts of the other target haloacetaldehydes (HAs). The stability of the HAs stock solutions was solvent dependent: in acetone, the brominated species partially degraded to bromoacetone, while all target HAs were stable in MTBE for up to 8 months. The analytical parameters, required for the quantification of HAs in water, were determined and used to evaluate the stability of the HAs in water. Under the conditions of the sampling protocol (field pH adjustment to pH 4.5 and storage at 4 degrees C), the target HAs were stable in water for up to 14 days. However, at typical drinking water pH and temperature conditions, the stability varied with the HA species, pH, temperature and storage period. The trihalogenated acetaldehydes degraded, in part, to their corresponding trihalomethanes (THMs) at increasing pH and temperature. Most target HAs were detected in drinking water samples collected from various Canadian drinking water systems, and the speciation was dependent on water parameters (e.g. bromide concentration) and treatment processes. From the water samples analysed, chloral hydrate ranged between 7% and 51% of the total HAs (w/w). The weigh ratio of total HAs to total THMs (10-46%) indicated that HAs contributed significantly to the pool of DBPs in drinking water.  相似文献   
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