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171.
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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
174.
Yutao Wang Jian LiuLars Hansson Kai ZhangRenqing Wang 《Journal of Cleaner Production》2011,19(4):303-310
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
175.
Safety measures and related costs and benefits have been widely discussed and analysed in academic circles and by the authorities and industrial sectors. The study reported in this paper addresses these aspects from a cognitive based perspective. Risk management is about dealing with the conflict between production and safety. Enterprises which spend too much on safety will meet bankruptcy, and those not concerned with safety measures will meet with severe accidents and related damage. Inspired by James Reason’s theoretical framework, managers (n = 106) of commercial transport enterprises were asked about their attitudes towards safety management, what factors have contributed and their belief that further effort and investments in health, environment and safety (HES) measures will pay off. One half of the managers perceive HES work as too expensive and approximately one quarter assess mandatory HES work as compromising their competitiveness. One third of the managers do not find further safety measures than those already implemented necessary or remunerative. They claim that there are no other alternative ways of doing their activities and that there are no technical measures available that could meet outstanding safety challenges. Managers do acknowledge HES work as important for the reputation of the enterprise. The factor analysis gave five HES attitude factors: (I) concerned with formalities, (II) HES work improves health, environment and safety, (III) HES work is ineffective, (IV) HES regulation is appropriate, and (V) HES work can be improved. 相似文献
176.
Nicholas D. Higgs Adam J. Reed Rachel Hooke David J. Honey Olaf Heilmayer Sven Thatje 《Marine Biology》2009,156(5):1073-1081
We present information on the reproductive biology, population structure, and growth of the brooding Antarctic bivalve Adacnarca nitens Pelseneer 1903, from the Ross Sea, Antarctica. Individuals ranging from 0.85 to 6.00 mm were found attached to a hydrozoan colony. This
species shows low fecundity and large egg size, common to other brooding species. The minimum size at which oogenesis was
detected was 2.3 mm and the minimum size at which brooding was evident was 3.9 mm. Embryos of a full range of developmental
stages were brooded simultaneously in females. The population showed a log–normal distribution and results suggest non-periodic
reproduction with continuous embryonic development. The reproductive traits of A. nitens are discussed in the context of circum-Antarctic species distribution and limitations to dispersal in brooding benthic invertebrates. 相似文献
177.
Rainer W. Sieke Günter Lippke Alfred Krippendorf Rainer Haas Sven Lüdtke 《Environmental science and pollution research international》1998,5(4):199-201
The new technology of Plasmazon® uses the extremely strong oxidation of radicals to break up the compocunds of organic connections, e.g. chemical warfare agents like Clark I. In making a comparison of oxidation to normal ozone, the factor of the Plasmazon® -technology is available up to 103. The investigation in an experimental test shows that it is possible to destroy the warfare agent character of Clark I. As the possibility of a large-lot application this technology is the method of choice for other chemical or biological warfare agents. 相似文献
178.
Wulff S Lindelöw Å Lundin L Hansson P Axelsson AL Barklund P Wijk S Ståhl G 《Environmental monitoring and assessment》2012,184(4):2453-2464
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
179.
Changes in habitat suitable for breeding of two sympatric raptor species (Haliaeetus albicilla and Aquila pomarina) were analysed along one of the most important breeding sites in Croatia for both species. The habitat suitability modelling was used to assess the influence of forestry practice during 2000-2006 using the known data on nesting places along research area. The four most important variables for lesser spotted eagle were elevation, distance from the nearest pasture, vertical distance to the nearest channel network and broadleaved forest placement (second axis from the principal component analysis of the enhanced vegetation index (EVI) index of MODIS images; November-March). The variables where white-tailed eagles showed greatest shift from overall habitat characteristics in the research area were broadleaved forest (second axis from the principal component analysis of the EVI index), height above the sea level, distance from the small settlements, vertical distance to channel network - all with negative loadings. The results clearly reveal the disproportion of suitable forests for raptors that were cut down in comparison to maturation of suitable forests. 相似文献
180.