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201.
Charles P. Gerba Adam Ross Kazue Takizawa Ian L. Pepper 《Food and environmental virology》2011,3(1):43-45
The ASTM Method D4994-89 has been used in the United States for almost two decades to assess the virological quality of biosolids.
However, the efficiency of this method for recovery of different enteric viruses has never been determined. The method was
found to recover several different enteroviruses and adenovirus 2 with an efficiency ranging from 18.1 ± 5.5 to 24.6 ± 7.8%. 相似文献
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205.
Odor and greenhouse gas (GHG) emissions from stored pig (Sus scrofa) manure were monitored for response to changes in the crude protein level (168 or 139 g kg(-1), as-fed basis) and nonstarch polysaccharide (NSP) content [i.e., control, or modified with beet pulp (Beta vulgaris L.), cornstarch, or xylanase] of diets fed to pigs in a production setting. Each diet was fed to one of eight pens of pigs according to a 2 x 4, full-factorial design, replicated over three time blocks with different groups of animals and random assignment of diets. Manure from each treatment was characterized and stored in a separate, ventilated, 200-L vessel. Repeated measurements of odor, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions from the vessels were taken every two weeks for eight weeks. Manure from high-protein diets had higher sulfur concentration and pH (P < or = 0.05). High-NSP (beet pulp) diets resulted in lower manure nitrogen and ammonia concentrations and pH (P < or = 0.05). Odor level and hedonic tone of exhaust air from the storage vessel headspaces were unaffected by the dietary treatments. Mean CO2 and CH4 emissions (1400 and 42 g d(-1) m(-3) manure, respectively) increased with lower dietary protein (P < or = 0.05). The addition of xylanase to high-protein diets caused a decrease in manure CO2 emissions, but an increase when added to low-protein diets (P < or = 0.05). Nitrous oxide emissions were negligible. Contrary to other studies, these results do not support the use of dietary protein reduction to reduce emissions from stored swine manure. 相似文献
206.
Ross Marshall Thomas B. Fischer 《Journal of Environmental Planning and Management》2006,49(2):279-299
Since 21 July 2004, formal strategic environmental assessment (SEA) requirements are in place for certain plans and programmes in European Union member states. Many public plans and programmes have been identified to fall under these requirements, and there has been a range of research activities particularly in land use and transport planning. However, the way in which SEA is to be applied in the private sector has remained largely unclear. Furthermore, to date there has been comparatively little reported private sector experience and the concrete benefits that SEA may deliver to private companies have not yet been discussed to any large extent. In order to address this shortcoming, the paper looks at SEA application in electricity transmission planning, taking the specific case of the privatized company ScottishPower as an example. Based on the evidence obtained, it is suggested that a structured SEA process can strengthen the environmental component and improve private sector decision-making processes. Corporate governance can be improved, if SEA is applied in a tiered system, addressing different issues and tasks at distinct stages in a clearly defined decision making hierarchy. 相似文献
207.
Biological barriers are a beneficial application of biofilms that aim at reducing the hydraulic conductivity (K) in geological formations. Several studies have shown the potential benefits of creating such barriers either by stimulating the indigenous microbial community (biostimulation) or injecting bacteria (bioaugmentation). For example, laboratory experiments show that groundwater microorganisms attached to a ceramic surface and generated a biofilm as thick as 1,100 μm. In a limestone fracture, this bacterial community clogged a single fracture up to 99.2 percent within 22 days. At the field scale, applications in porous aquifers led to a five‐fold decrease in K after 2.5 days of biostimulation, and a bioaugmentation with a starved, adapted bacterial culture decreased K by 99.4 percent. One promising development of the biobarrier concept is a field application at a fractured bedrock site. Using a multidisciplinary approach and focusing on a well‐characterized fracture system, a field trial was undertaken in Southern Ontario to measure the extent of bioclogging and the stability over time. This article focuses on the literature pertinent to the preparation of this field trial and presents the innovative approach selected to monitor the bioclogging in such a challenging environment. 相似文献
208.
A. Ross Kiester 《Behavioral ecology and sociobiology》1979,5(4):323-330
Summary In an experimental choice situation, individuals of both sexes of the lizard Anolis auratus choose to associate with a conspecific individual regardless of its sex. Further, individuals of both sexes associate with an individual of A. tropidogaster, a related species. Given the choice between the two species, they choose their own. Given the choice between a conspecific and a small patch of natural habitat, they do not choose one or the other consistently. These experiments indicate that conspecific association does not function just as a mate selection mechanism as has been previously proposed. The initial association may, in addition, serve a habitat selection function. Conspecifics can thus be seen as cues indicating the presence of suitable habitat as well as being important biological factors in themselves. 相似文献
209.
Klaus Keil Benton C. Clark A. K. Baird Priestley Toulmin III Harry J. Rose Jr. 《Die Naturwissenschaften》1978,65(5):231-238
Analyses of 13 samples of Martian surface materials with the Viking X-ray fluorescence spectrometers show SiO2 similar to that of terrestrial mafic rocks, whereas Fe2O3, Cl, and S are higher and Al2O3, K2O, Rb, Sr, Y, and Zr are lower. Low totals suggest presence of CO2, H2O, and Na2O. Duricrust fragments are higher in S than fines, but samples from both landing sites are surprisingly similar. We suggest that Martian surface materials are aeolian deposits of complex mixtures of weathering products of maficultramafic rocks, possibly consisting of iron-rich clays, sulfates, iron oxides, carbonates, and chlorides. 相似文献
210.
The authors present short- and long-term supply schedules for the primary US copper industry. These schedules are based on the economic theory of supply, and are derived from site- and input-specific cost data. Cost figures are arrived at by a combination of engineering process analysis and statistical cost estimation. The supply functions can be used to evaluate the effects of changes in market, policy, or other variables on US copper supply. 相似文献