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61.
Leading societies toward a more sustainable, equitably shared, and environmentally just future requires elevating and strengthening conversations on the nonmaterial and perhaps unquantifiable values of nonhuman nature to humanity. Debates among conservationists relating to the appropriateness of valuing ecosystems in terms of their human utility have eclipsed the more important and impactful task of expressing conservation concerns in terms that are meaningful to diverse stakeholders. We considered the wide global diversity of perspectives on the biosocial complex—the relationships and interactions between all living species on Earth—and argue that humanity's best chance for effective conservation is to take a pluralistic approach that engages seriously with the worldviews of all stakeholders. Many worldviews—particularly those in indigenous cultures—place a higher value on the spiritual and nonmaterial aspects than what is often represented by the discourse surrounding Western conservation policy. Alternative framings of the biosocial complex that recognize nature's intrinsic value can be powerful motivators for social change and for local-scale conservation efforts. At a national and international level, changing ethical framings of human relationships with nature have started influencing conceptions of human rights relating to the environment and of the rights of nature itself. This change has led to an increased role of the judiciary in promoting environmental sustainability and promoting justice for groups who are most often affected by environmental harms. We hope our essay will motivate the scientific community to change its own perception of what a sound and sustainable relationship between humanity and other species should be and will help citizens become active environmental subjects, connected to the ecosystems around them.  相似文献   
62.
63.
Contact pheromones mediate mate recognition and play important roles in mating systems of longhorned beetles (Coleoptera: Cerambycidae). One common bioassay of contact chemoreception in cerambycids involves presenting a freeze-killed female to a male in a Petri dish arena. If the male attempts to mate with the female carcass, it confirms that mate recognition signals are present and intact and behavior is not involved. Cuticular hydrocarbons are then stripped from the female with successive solvent washes, rendering her unattractive to males and also resulting in a crude extract containing the cuticular hydrocarbons. To test the bioactivity of the crude extract, the same female is then treated with the extract and presented again to the male. Males of some species, including Megacyllene robiniae (F?rster), respond less readily to reconstituted females than to those same beetles before they were solvent-extracted. In the present study, we test the hypothesis that the contact pheromone of M. robiniae, Z9:C25, exists as a layer on the surface of the epicuticle. We used solid phase microextraction (SPME) to sample cuticular hydrocarbons of female beetles after they were freeze-killed, solvent washed, and treated with crude cuticular extracts. We found that extracting cuticular hydrocarbons from females and applying the resulting crude extract back onto the solvent-washed cadaver scrambles the wax layer and decreases the abundance of the contact pheromone presented on the surface of the insect.  相似文献   
64.

Introduction

Deaths from fires and burns are a leading cause of fatal home injury in the United States. Smoke alarms are one of the most effective interventions to prevent residential fire deaths. Nationwide, more than 95% of homes are estimated to have at least one smoke alarm. There is evidence that homes at highest risk of fire deaths lag behind national averages in smoke alarm use and maintenance.

Method

We compiled a comprehensive list of published studies that focus on smoke alarm prevalence in high-risk homes. Our findings show that there are substantial gaps in both smoke alarm presence and functional status between high-risk homes and national average estimates.

Conclusions

To save more lives, improved efforts are needed to reduce the disparity in smoke alarm prevalence and functional use in the United States.  相似文献   
65.
Abstract

A study was conducted from summer 1995 to summer 1997 to assess the seasonal occurrence of pesticide residues and other organic contaminants, polychlorinated biphenyls (PCBs), in water at the estuaries of Rosetta and Damiatta branches of the Nile river. The results indicated that organochlorine compounds (OCs) including HCB, lindane, p,p‘‐DDE, p,p‘DDD, p,p‘‐DDT, aroclor 1254 and aroclor 1260 were present in all the water samples at concentration levels ranging between 0.195–0.240, 0.286–0.352, 0.035–0.067, 0.019–0.033, 0.024–0.031, 0.390–0.70 and 0.166–0.330 μg/l, respectively. The levels of these compounds were higher in water of Damiatta branch than those found in water of Rosetta branch. Aldrin, dieldrin and endrin were not detected in all water samples. Only 4 compounds from 36 organophosphorus insecticides, fungicides and s‐triazine herbicides tested were detected in water samples collected during summer and autumn seasons from Rosetta branch. The concentration levels of these detected compounds, dimethoate, malathion, captan, and ametryne, ranged from 0.011 to 0.340 μg/l, respectively. Similar compounds during the same seasons as found in water of Rosetta branch were also detected in water of Damiatta branch except ametryne. The levels of the detected compounds (dimethoate, malathion and captan) ranged between 0.030 and 0.330 μg/l. The levels of detected organophosphorus insecticides, fungicides and s‐triazine herbicides were in the order: dimethoate > malathion > captan > ametryne.  相似文献   
66.
Analysis of biochemical components and measurements of oxygen consumption rates of cypris larvae of Balanus balanoides (L.) maintained in the laboratory at 10°C for up to 5 weeks after capture shows that lipid is the primary energy reserve, although later protein is utilised. Initially, the cyprids swim freely with an oxygen consumption rate of ca. 37×10-3 l O2 h-1 cyprid-1, but within a few days the rate falls to ca. 21×10-3 l O2 h-1 cyprid-1 when they cease swimming and explore the substratum. The cost of metamorphosis was calculated both from the loss of biochemical components and oxygen consumption rates during metamorphosis; the values were 2.8×10-2 and 3.2×10-2 cal cyprid-1, respectively. A budget was collated from the data on respiration and biochemical composition, whereby the energy per cyprid was partitioned into that required for essential structural components (6.8×10-2 cal), that needed for metamorphosis (3.0×10-2 cal) and an excess available for swimming and exploring, which in the batches studied was about 5.0×10-2 cal. This excess is mainly derived from the utilisation of lipid reserves and is used up usually 2 1/2 to 4 weeks after capture. During these measurements, samples of cyprids were taken at weekly intervals to test the rate of settlement and success of metamorphosis. The results showed that they lose their competence to metamorphose successfully approximately at the same time (3 to 4 weeks) that the energy supply for swimming and exploration is used up.  相似文献   
67.
Aspects of feather star behavior and ecology were recorded by time-lapse cinematography approximately 1 frame min-1 on the Great Barrier Reef, Australia over a 1 mo period in 1983. The current regime influenced body postures of most species studied, whether nocturnal or not. Moreover, feather stars of several species crawled on the substratum with their arms; each crawling episode lasted roughly 10 min, and the maximum speed attained was about 1 arm length min-1. Nocturnal feather stars crawled to their nighttime feeding perches around dusk and crawled back to their daytime hiding places around dawn. Surprisingly, some species of feather stars living on the reef surface both day and night also crawled around at dawn and dusk for reasons that are not known. In the time-lapse films, and individual of Comanthus bennetti (sex undetermined) spawned for about 2 min just after dark on 5 July 1983. Another film showed possible predation on a feather star (Himerometra robustipinna) by a saddled coralfish (Chaetodon ephippium).  相似文献   
68.
Bayesian entropy for spatial sampling design of environmental data   总被引:1,自引:0,他引:1  
We develop a spatial statistical methodology to design national air pollution monitoring networks with good predictive capabilities while minimizing the cost of monitoring. The underlying complexity of atmospheric processes and the urgent need to give credible assessments of environmental risk create problems requiring new statistical methodologies to meet these challenges. In this work, we present a new method of ranking various subnetworks taking both the environmental cost and the statistical information into account. A Bayesian algorithm is introduced to obtain an optimal subnetwork using an entropy framework. The final network and accuracy of the spatial predictions is heavily dependent on the underlying model of spatial correlation. Usually the simplifying assumption of stationarity, in the sense that the spatial dependency structure does not change location, is made for spatial prediction. However, it is not uncommon to find spatial data that show strong signs of nonstationary behavior. We build upon an existing approach that creates a nonstationary covariance by a mixture of a family of stationary processes, and we propose a Bayesian method of estimating the associated parameters using the technique of Reversible Jump Markov Chain Monte Carlo. We apply these methods for spatial prediction and network design to ambient ozone data from a monitoring network in the eastern US.  相似文献   
69.
Increases in the deposition of anthropogenic nitrogen (N) have been linked to several terrestrial ecological changes, including soil biogeochemistry, plant stress susceptibility, and community diversity. Recognizing the need to identify sensitive indicators of biotic response to N deposition, we empirically estimated the N critical load for changes in alpine plant community composition and compared this with the estimated critical load for soil indicators of ecological change. We also measured the degree to which alpine vegetation may serve as a sink for anthropogenic N and how much plant sequestration is related to changes in species composition. We addressed these research goals by adding 20, 40, or 60 kg N x ha(-1) x yr(-1), along with an ambient control (6 kg N x ha(-1) x yr(-1) total deposition), to a species-rich alpine dry meadow for an eight-year period. Change in plant species composition associated with the treatments occurred within three years of the initiation of the experiment and were significant at all levels of N addition. Using individual species abundance changes and ordination scores, we estimated the N critical loads (total deposition) for (1) change in individual species to be 4 kg N x ha(-1) yr(-1) and (2) for overall community change to be 10 kg N x ha(-1) x yr(-1). In contrast, increases in NO3- leaching, soil solution inorganic NO3-, and net N nitrification occurred at levels above 20 kg N x ha(-1) x yr(-1). Increases in total aboveground biomass were modest and transient, occurring in only one of the three years measured. Vegetative uptake of N increased significantly, primarily as a result of increasing tissue N concentrations and biomass increases in subdominant species. Aboveground vegetative uptake of N accounted for <40% of the N added. The results of this experiment indicate that changes in vegetation composition will precede detectable changes in more traditionally used soil indicators of ecosystem responses to N deposition and that changes in species composition are probably ongoing in alpine dry meadows of the Front Range of the Colorado Rocky Mountains. Feedbacks to soil N cycling associated with changes in litter quality and species composition may result in only short-term increases in vegetation N pools.  相似文献   
70.
The dictyoceratid marine sponge Dysidea herbacea (Keller, 1889) is common in shallow waters of the tropical Pacific Ocean. Polybrominated biphenyl ethers such as 2-(2,4-dibromophenyl)-4,6-dibromophenol (1) are characteristic secondary metabolites of some specimens of this sponge and may represent as much as 12% of the dry weight. We have found 1 to be deposited as conspicuous crystals throughout the sponge tissue. The dominant prokaryotic endosymbiont in the mesohyl of the sponge is a filamentous cyanobacterium (Oscillatoria spongeliae), although a vacuole-containing, heterotrophic bacterium is also present. The cyanobacteria were separated from the sponge cells and heterotrophic bacteria by flow cytometry. Coupled gas chromatography—mass spectrometry and proton nuclear magnetic-resonance spectroscopy revealed that the major brominated Compound 1 isolated from the intact symbiotic association is found in the cyanobacteria and not in the sponge cells or heterotrophic bacteria. This suggests that the production of the compound is due to the cyanobacterium, and not to the sponge or symbiotic heterotrophic bacteria, as had been suggested earlier.  相似文献   
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