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81.
In this paper, we hypothesize and test the ideas that (1) people’s subjectivity in relation to aircraft noise is shaped by the policy discourse, (2) this results in a limited number of frames towards aircraft noise, (3) the frames inform people how to think and feel about aircraft noise and (4) the distribution of the frames in the population is dependent on structural variables related to the individual. To reveal subjects’ frames of aircraft noise a latent class model is estimated based on survey data gathered among a sample of 250 residents living near Amsterdam Airport Schiphol, a major international airport in the Netherlands. In line with expectations, the results show that there are four evaluative frames of aircraft noise, three of which are strongly linked to the policy discourse. The frames are associated with fitting levels of annoyance response. In turn, frame membership is influenced by two structural variables, namely aircraft noise exposure and noise sensitivity. The results indicate that social factors operate discursively in the explanation of subjective reaction to noise, while psychological factors operate within a traditional cause-and-effect model. The paper concludes with several policy implications.  相似文献   
82.
The Argentine Pampas, one of the main agricultural areas in the world, recently has undergone significant changes in land use and structural characteristics of agricultural production systems. Concerns about the environmental and societal impacts of the changes motivated development of an agent-based model (ABM) to gain insight on processes underlying recent observed patterns. The model is described following a standard protocol (ODD). Results are discussed for an initial set of simplified simulations performed to understand the processes that generated and magnified the changes in the Pampas. Changes in the structure of agricultural production and land tenure seem to be driven by differences among farmers’ ability to generate sufficient agricultural income to remain in business. In turn, as no off-farm or credit is modeled, economic sustainability is tied to initial resource endowment (area cropped). Farmers operating small areas are economically unviable and must lease out their farms to farmers operating larger areas. This leads to two patterns: (a) a concentration of production (fewer farmers operating larger areas) and, (b) an increase in the area operated by tenants. The simulations showed an increase of soybean area, linked to the higher profitability of this crop. Despite the stylized nature of initial simulations, all emerging patterns are highly consistent with changes observed in the Pampas.  相似文献   
83.
Summary The phenotypic cues that provide for rejection of non-nestmates by workers of the ant genus Camponotus could derive from any or all of four sources: (1) environmental odors; (2) the individual's own genetically-determined recognition pheromones or discriminators; (3) a gestalt or mixture of transferable discriminators, produced by each nestmate and absorbed by all; and/or (4) the discriminators of the queen applied to all nestmates. To test these hypotheses, four series of small experimental colonies were created: inter- and intraspecific mixed colonies containing queens, queenless worker groups, and pairs of worker groups between which a single queen was repeatedly switched. Intraspecific mixed colonies and queenless groups were further divided into groups receiving different diets. Aggression of workers in 165 experimental colonies was assayed in a total of 4064 neutral arena tests. Workers adopted into inter- and intraspecific mixed colonies with queens were highly aggressive to unfamiliar kin from pure colonies, independent of diet and of the proportion of different kin groups in the colony. However, queenless workers exhibited less aggression to unfamiliar kin than to non-kin, demonstrating the existence of worker discriminators. Diet differences slightly enhanced aggression among unfamiliar queenless kin. Non-kin sharing a switched queen were as unaggressive to one another as were sisters. The ability to adopt queenless workers between colonies gradually declined over 1–2 wks following their emergence from pupae. We propose a hierarchy of importance of cue sources in determining nestmate discrimination in small Camponotus colonies: Queen discriminators> worker discriminators>environmental cues. A flow-diagram model of social insect kin recognition, based on the phenotype matching concept of Holmes and Sherman (1983), is discussed.  相似文献   
84.
85.
BACKGROUND: Mold growth is believed to be one causative factor underlying the association between dampness in buildings and increased respiratory morbidity. Measurements of beta(1-->3)-glucans and fungal extracellular polysaccharides (EPS) are used as markers of mold exposure in field studies. Little is known about their levels and determinants in homes. OBJECTIVE: To study levels and determinants of beta(1-->3)-glucan and EPS levels in mattress and living room floor dust in three European countries. METHODS: Mattress and living room floor dust was collected in the homes of 1065 German, Dutch, and Swedish (pre-)school children. All samples were analyzed for beta(1-->3)-glucans and EPS in one central laboratory. Determinants were assessed by questionnaire. RESULTS: Amounts of dust, EPS and beta(1-->3)-glucan levels differed between countries. Amounts of dust, beta(1-->3)-glucan and EPS levels for mattresses were only weakly correlated with those for living room floors. Floor dust beta(1-->3)-glucan loads, EPS loads and EPS concentrations were strongly correlated with the amount of dust sampled, which is largely determined by the type of floor that was sampled (carpeted floors had 5-20 higher amounts of dust). None of the other determinants was consistently and statistically significantly associated with amounts of dust, beta(1-->3)-glucan and EPS concentrations on floors and mattresses. CONCLUSION: Mattress dust and floor dust are two different measures of exposure to the investigated mold components. Living room floor beta(1-->3)-glucan and EPS loads and EPS concentrations are largely determined by the type of floor sampled. Differences between countries can only partly be explained by the determinants studied.  相似文献   
86.
Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.  相似文献   
87.
Fin whale (Balaenoptera physalus quoyi) habitat use and its relationship to environmental conditions are generally unknown in the Southern Ocean, presenting challenges for predicting their seasonal occurrence and potential effects of fishing pressure and climate change on this endangered species. Using biological data collected during 14 shipboard surveys off the northern Antarctic Peninsula and oceanographic data from satellite remote sensing, we mapped the distribution of fin whale hotspots, Antarctic krill abundance (biomass from acoustics, concentrations from nets) and ocean conditions during mid- and late-summer to investigate the environmental determinants of whale hotspots. Generalized additive models (GAM) were used to test the hypothesis that intra-seasonal changes in fin whale hotspot distribution relate to sea surface temperature (SST), krill abundance and eddy kinetic energy (EKE). More whale hotspots (sightings and individuals) are observed during late- than mid-summer surveys. During mid-summer, hotspots occurred near Elephant Island while in late-summer they were distributed throughout the slope region in proximity to the mean location of the southern Antarctic Circumpolar Current Front. The spatial mean of EKE did not differ between mid- and late-summer surveys, but the spatial mean of SST was significantly warmer during late-summer. The GAM for mid-summer indicates that fin whale hotspots were positively related to SST, EKE and acoustically determined krill biomass. The GAM for late-summer indicates the hotspots were negatively related to net-based krill abundance and positively related to acoustic krill biomass and EKE. This study is important because environmental determinants of fin whale hotspots may be used as reference points for implementing future conservation plans for their recovering populations.  相似文献   
88.
89.
Stewardship to tackle global phosphorus inefficiency: The case of Europe   总被引:3,自引:0,他引:3  
The inefficient use of phosphorus (P) in the food chain is a threat to the global aquatic environment and the health and well-being of citizens, and it is depleting an essential finite natural resource critical for future food security and ecosystem function. We outline a strategic framework of 5R stewardship (Re-align P inputs, Reduce P losses, Recycle P in bioresources, Recover P in wastes, and Redefine P in food systems) to help identify and deliver a range of integrated, cost-effective, and feasible technological innovations to improve P use efficiency in society and reduce Europe’s dependence on P imports. Their combined adoption facilitated by interactive policies, co-operation between upstream and downstream stakeholders (researchers, investors, producers, distributors, and consumers), and more harmonized approaches to P accounting would maximize the resource and environmental benefits and help deliver a more competitive, circular, and sustainable European economy. The case of Europe provides a blueprint for global P stewardship.  相似文献   
90.
Extreme hydrometeorological events such as flash floods have caused considerable loss of life and damage to infrastructure over recent years. Flood events in the Mediterranean region between 1990 and 2006 caused over 4,500 fatalities and cost over €29 billion in damage, with Italy one of the worst affected countries. The Distributed Computing Infrastructure for Hydro‐Meteorology (DRIHM) project is a European initiative aiming at providing an open, fully integrated eScience environment for predicting, managing, and mitigating the risks related to such extreme weather phenomena. Incorporating both modeled and observational data sources, it enables seamless access to a set of computing resources with the objective of providing a collection of services for performing experiments with numerical models in meteorology, hydrology, and hydraulics. The purpose of this article is to demonstrate how this flexible modeling architecture has been constructed using a set of standards including the NetCDF and WaterML2 file formats, in‐memory coupling with OpenMI, controlled vocabularies such as CF Standard Names, ISO19139 metadata, and a Model MAP (Metadata, Adaptors, Portability) gateway concept for preparing numerical models for standardized use. Hydraulic results, including the impact to buildings and hazards to people, are given for the use cases of the severe and fatal flash floods, which occurred in Genoa, Italy in November 2011 and October 2014.  相似文献   
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