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61.
The olfactory circuitry of Drosophila melanogaster is becoming increasingly clear. However, how olfactory processing translates into appropriate behavioral responses is still poorly understood. Using a sibling species approach, we tested how a perturbation in the olfactory circuitry affects odor preference. In a previous study, we found that the sibling species of D. melanogaster, the specialist D. sechellia, overrepresents a sensillum, ab3, the A neuron of which is sensitive to hexanoate esters, characteristic of the species’ sole host, the Morinda citrifolia fruit. Concordantly, the corresponding glomerulus, DM2, is enlarged. In this study, we found that the ab3B neuron, the expansion of which was previously assumed to be pleiotropic and of no ecological significance, is in fact tuned to another morinda fruit volatile, 2-heptanone (HP). Axons of this neuron type arborize in a second enlarged glomerulus. In behavioral experiments we tested how this has affected the fly’s odor preference. We demonstrate that D. sechellia has a reversed preference for the key ligands of these macroglomeruli, especially at high concentrations. Whereas D. melanogaster was repelled by high concentrations of these odors, D. sechellia was highly attracted. This was the case for odors presented singly, but more notably for blends thereof. Our study indicates that relatively simple changes, such as a shift in sensillar abundance, and concordant shifts in glomerular size, can distort the resulting olfactory code, and can lead to saltatory shifts in odor preference. D. sechellia has exploited this to align its olfactory preference with its ecological niche.  相似文献   
62.
There has been much debate on the topic of whether stricter environmental regulations can promote environmental performance and economic performance at the same time. Different researchers have used different indicators to measure environmental performance and economic performance in their empirical studies. However, it is a surprise that few studies have checked the relationship between environmental regulation and eco-efficiency, as the latter is widely regarded as a quite powerful tool of considering ecology and economy together.In this study the background is the implementation in 2003 of the Stricter Discharge Standard (SDS) in Shandong Province’s Pulp and Paper Industry (SPPI), compared to the national standards of China. The stricter regulations were intended to promote corporate change from passive management to active control and from end-of-pipe treatment to cleaner production. This study investigated the eco-efficiency trends of SPPI from 2001 to 2008 in three fields: water efficiency, energy efficiency and environment efficiency. A “de-linking” and “re-linking” tool was used to attain a further evaluation. The study showed that with the implementation of stricter regulation most of the efficiency indicators (except CO2 emission and energy consumption) had achieved significant improvements, and the overall environmental performance trends of SPPI showed it to be more sustainable. However, the study also found that it was not enough to address a single indicator in the environmental regulation of the pulp and paper industry. More holistic eco-efficiency indicators need to be further considered and introduced to the industry as the next step to create true sustainable development.  相似文献   
63.
A revised Swedish forest health assessment system is presented. The assessment system is composed of several interacting components which target information needs for strategic and operational decision making and accommodate a continuously expanding knowledge base. The main motivation for separating information for strategic and operational decision making is that major damage outbreaks are often scattered throughout the landscape. Generally, large-scale inventories (such as national forest inventories) cannot provide adequate information for mitigation measures. In addition to broad monitoring programs that provide time-series information on known damaging agents and their effects, there is also a need for local and regional inventories adapted to specific damage events. While information for decision making is the major focus of the health assessment system, the system also contributes to expanding the knowledge base of forest conditions. For example, the integrated monitoring programs provide a better understanding of ecological processes linked to forest health. The new health assessment system should be able to respond to the need for quick and reliable information and thus will be an important part of the future monitoring of Swedish forests.  相似文献   
64.
Secondary metabolites produced by fungi and bacteria are among the potential agents that contribute to adverse health effects observed in occupants of buildings affected by moisture damage, dampness and associated microbial growth. However, few attempts have been made to assess the occurrence of these compounds in relation to moisture damage and dampness in buildings. This study conducted in the context of the HITEA project (Health Effects of Indoor Pollutants: Integrating microbial, toxicological and epidemiological approaches) aimed at providing systematic information on the prevalence of microbial secondary metabolites in a large number of school buildings in three European countries, considering both buildings with and without moisture damage and/or dampness observations. In order to address the multitude and diversity of secondary metabolites a large number of more than 180 analytes was targeted in settled dust and surface swab samples using liquid chromatography/mass spectrometry (LC/MS) based methodology. While 42%, 58% and 44% of all samples collected in Spanish, Dutch and Finnish schools, respectively, were positive for at least one of the metabolites analyzed, frequency of detection for the individual microbial secondary metabolites - with the exceptions of emodin, certain enniatins and physcion - was low, typically in the range of and below 10% of positive samples. In total, 30 different fungal and bacterial secondary metabolites were found in the samples. Some differences in the metabolite profiles were observed between countries and between index and reference school buildings. A major finding in this study was that settled dust derived from moisture damaged, damp schools contained larger numbers of microbial secondary metabolites at higher levels compared to respective dust samples from schools not affected by moisture damage and dampness. This observation was true for schools in each of the three countries, but became statistically significant only when combining schools from all countries and thus increasing the sample number in the statistical analyses.  相似文献   
65.
The future of sustainability science: a solutions-oriented research agenda   总被引:1,自引:0,他引:1  
Over the last decade, sustainability science has been at the leading edge of widespread efforts from the social and natural sciences to produce use-inspired research. Yet, how knowledge generated by sustainability science and allied fields will contribute to transitions toward sustainability remains a critical theoretical and empirical question for basic and applied research. This article explores the limitations of sustainability science research to move the field beyond the analysis of problems in coupled systems to interrogate the social, political and technological dimensions of linking knowledge and action. Over the next decade, sustainability science can strengthen its empirical, theoretical and practical contributions by developing along four research pathways focused on the role of values in science and decision-making for sustainability: how communities at various scales envision and pursue sustainable futures; how socio-technical change can be fostered at multiple scales; the promotion of social and institutional learning for sustainable development.  相似文献   
66.
Long-range atmospheric transport is a major pathway for delivering persistent organic pollutants to the oceans. Atmospheric deposition and volatilization of chlorinated pesticides and algae-produced bromoanisoles (BAs) were estimated for Bothnian Bay, northern Baltic Sea, based on air and water concentrations measured in 2011–2012. Pesticide fluxes were estimated using monthly air and water temperatures and assuming 4 months ice cover when no exchange occurs. Fluxes were predicted to increase by about 50 % under a 2069–2099 prediction scenario of higher temperatures and no ice. Total atmospheric loadings to Bothnian Bay and its catchment were derived from air–sea gas exchange and “bulk” (precipitation + dry particle) deposition, resulting in net gains of 53 and 46 kg year?1 for endosulfans and hexachlorocyclohexanes, respectively, and net loss of 10 kg year?1 for chlordanes. Volatilization of BAs releases bromine to the atmosphere and may limit their residence time in Bothnian Bay. This initial study provides baseline information for future investigations of climate change on biogeochemical cycles in the northern Baltic Sea and its catchment.  相似文献   
67.
Upper Awash Agro Industry Enterprises (UAAIE) is one of the major state farms in Ethiopia with known large-scale pesticide use. Although organochlorine pesticides (OCPs) have been applied for about three decades, no studies have been carried out on levels of residue in the region. In this work a fast selective pressurised liquid extraction (SPLE) methodology has successfully been applied for screening of 13 OCPs in 12 soil samples from different fields in UAAIE, which further strengthen this methodology. Quantitative and qualitative analyses were done using a dual column gas chromatography-electron capture detection system (GC-ECD) and a GC equipped with a mass spectrometer (MS), respectively. The main contaminants identified comprised of previously used persistent organic pollutants (POPs) and currently used insecticides. Low concentrations or non-detectable levels of certain OCPs (aldrin, dieldrin, endrin, and heptachlor) indicate a positive phasing out of these persistent organic pollutants (POPs). Similarly HCHs were found in few soils and at low concentrations. Endosulfans and DDTs were detected in substantial amounts in the soils with Sigmaendosulfans up to 56000 and SigmaDDTs up to 230 ng g(-1) dry weight, which is a threat to the surrounding and downstream ecosystems, especially considering that the investigated OCPs constituted 29000 l of the 63000 l of pesticide applied annually on the fields. Additional concerns must be raised concerning synergistic effects of all pesticides added.  相似文献   
68.
A framework for evaluation of flood management strategies   总被引:2,自引:0,他引:2  
The resulting impact of disasters on society depends on the affected country's economic strength prior to the disaster. The larger the disaster and the smaller the economy, the more significant is the impact. This is clearest seen in developing countries, where weak economies become even weaker afterwards. Deliberate strategies for the sharing of losses from hazardous events may aid a country or a community in efficiently using scarce prevention and mitigation resources, thus being better prepared for the effects of a disaster. Nevertheless, many governments lack an adequate institutional system for applying cost effective and reliable technologies for disaster prevention, early warnings, and mitigation. Modelling by event analyses and strategy models is one way of planning ahead, but these models have so far not been linked together. An approach to this problem was taken during a large study in Hungary, the Tisza case study, where a number of policy strategies for spreading of flood loss were formulated. In these strategies, a set of parameters of particular interest were extracted from interviews with stakeholders in the region. However, the study was focused on emerging economies, and, in particular, on insurance strategies. The scope is now extended to become a functional framework also for developing countries. In general, they have a higher degree of vulnerability. The paper takes northern Vietnam as an example of a developing region. We identify important parameters and discuss their importance for flood strategy formulations. Based on the policy strategies in the Tisza case, we extract data from the strategies and propose a framework for loss spread in developing and emerging economies. The parameter set can straightforwardly be included in a simulation and decision model for policy formulation and evaluation, taking multiple stakeholders into account.  相似文献   
69.
在<污染综合预防和控制法>的背景下,丹麦一家企业Kommunekemi帮助编写了有关更安全地处理有害废物的最有效技术的欧盟参考文献.几年前Kommunekemi面临着环境影响和职业健康与安全问题.1990年代安装了两个新的圆桶自动卸料系统(一个用于废液,一个用于固体和糊状废物).本文介绍了Kommunekemi公司内部和周围改善环境和安全条件所采用的方法.  相似文献   
70.
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