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11.
We have earlier shown that radio frequency electromagnetic fields can cause significant leakage of albumin through the blood–brain barrier of exposed rats as compared to non-exposed rats, and also significant neuronal damage in rat brains several weeks after a 2 h exposure to a mobile phone, at 915 MHz with a global system for mobile communications (GSM) frequency modulation, at whole-body specific absorption rate values (SAR) of 200, 20, 2, and 0.2 mW/kg. We have now studied whether 6 h of exposure to the radiation from a GSM mobile test phone at 1,800 MHz (at a whole-body SAR-value of 13 mW/kg, corresponding to a brain SAR-value of 30 mW/kg) has an effect upon the gene expression pattern in rat brain cortex and hippocampus—areas where we have observed albumin leakage from capillaries into neurons and neuronal damage. Microarray analysis of 31,099 rat genes, including splicing variants, was performed in cortex and hippocampus of 8 Fischer 344 rats, 4 animals exposed to global system for mobile communications electromagnetic fields for 6 h in an anechoic chamber, one rat at a time, and 4 controls kept as long in the same anechoic chamber without exposure, also in this case one rat at a time. Gene ontology analysis (using the gene ontology categories biological processes, molecular functions, and cell components) of the differentially expressed genes of the exposed animals versus the control group revealed the following highly significant altered gene categories in both cortex and hippocampus: extracellular region, signal transducer activity, intrinsic to membrane, and integral to membrane. The fact that most of these categories are connected with membrane functions may have a relation to our earlier observation of albumin transport through brain capillaries.  相似文献   
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The goal of ecosystem-based management (EBM) is to support a sustainable and holistic multisectored management approach, and is recognized in a number of international policy frameworks. However, it remains unknown how these goals should be linked to assessments and management plans for marine fauna, such as mammals and fish stocks. It appears particularly challenging to carry out trade-off analyses of various ocean uses without a framework that integrates knowledge of environmental, social, and economic benefits derived from nonstationary marine fauna. We argue this gap can be filled by applying a version of the ecosystem-service approach at the population level of marine fauna. To advance this idea, we used marine mammals as a case study to demonstrate what indicators could operationalize relevant assessments and deliver an evidence base for the presence of ecosystem services and disservices derived from marine mammals. We found indicators covering common ecosystem service categories feasible to apply; examples of indicator data are already available in the literature for several populations. We encourage further exploration of this approach for application to marina fauna and biodiversity management, with the caveat that conceptual tensions related to the use of the ecosystem service concept itself needs to be addressed to ensure acceptance by relevant stakeholders.  相似文献   
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The morphology of the grooming limbs, the 5th pair of pereiopods, was studied by scanning electron microscopy in six species of porcellanid crabs, Petrolisthes cabrilloi, P. cinctipes, P. armatus, P. galathinus, Pachycheles monilifer, and Pachycheles rudis, and their function was inferred by comparison with findings from previous studies. Grooming limb morphology was almost identical among the four Petrolisthes species and differed little compared to that of the two Pachycheles species. The 5th pereiopods bore a basal tuft of mechanoreceptive setae, three different types of grooming setae armed with setules or denticles, two types of smooth sensilla for location and identification of fouling objects, and a terminal, toothed chela for picking firmly attached objects off the gills and body. The grooming limb was extremely flexible and could reach most parts of the body, including the gill chamber on the opposite side. The grooming limb morphology in Petrolisthes cabrilloi is consistent with its wellknown effectiveness in preventing parasitism by the rhizocephalan Lernaeodiscus porcellanae. Grooming setae remove recently attached cyprids, while the chela can grip and remove the much smaller, firmly attached kentrogons. Porcellanid crabs not known to host rhizocephalans, however, had grooming limbs almost identical to those of Petrolisthes cabrilloi despite their previously demonstrated failure to prevent settlement and infestation by L. porcellanae larvae. The effectiveness of P. cabrilloi in removing kentrogons, therefore, seems also to depend on behavioral adaptations whereby this species recognizes the parasite larvae as high-threat objects.  相似文献   
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The reproducibility of odor thresholds determined by forced-choice dynamic triangle olfactometry was studied employing panels of 23- 45 subjects who tested 12 odorants, with four replications for one (1-butanol). Depending on the selection of panelists, their number, and between-session differences in olfactometer variables, the standard deviation of log(threshold) values ranged from 0.12 (same session, different panels of nine) to 0.37 (different sessions, different panels of nine).

Among the demographic factors, only age was found significant; those below age of 30 were 1.6-3 times more sensitive than the older group. No systematic sensitivity difference was found between females and males, and nonsmokers and smokers.

Suspicion has been raised in the literature that the method used here, ASTM E679, yields biased results. It is shown for panels of 6-45 members that such biases are inconsequential if the range of concentration presented to the panelists is large enough, and the group threshold is well within that range. The Hall-Ellis method of calculation may have a slight advantage for panels of less than eight subjects, but such small panels are not advisable because of their high variability. The method based on the detectability index exhibited more scatter and would need an impracticaliy large number of measurements.  相似文献   
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The radionuclide (99)Tc had been discharged from the nuclear reprocessing facility in Sellafield (UK) into the Irish Sea in increased amounts in the 1990s. We compare the simulated dispersion of (99)Tc in surface water as calculated by a hydrodynamic model and an assessment box model with field-observations from 1996 to 1999 to study concentrations, pathways and travel times. The model results are consistent with the observations and show the typical pathway of dissolved radionuclides from the Irish Sea via the North Sea along the Norwegian Coast. Subsequently the contaminated water separates into three branches of which the two Arctic branches bear the potential for future monitoring of the signal in the next decades. The results of the hydrodynamic model indicate a large variability of surface concentrations in the West Spitsbergen Current which has implications for future monitoring strategies. According to the observed and simulated distributions we suggest an improved box model structure to better capture the pattern for concentrations at the surface.  相似文献   
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This paper addresses recent calls to narrow the micro–macro gap in management research (Bamberger, 2008), by incorporating a macro‐level context variable (country) in exploring micro‐level determinants of board effectiveness. Following the integrated model proposed by Forbes and Milliken (1999), we identify three board processes as micro‐level determinants of board effectiveness. Specifically, we focus on effort norms, cognitive conflicts and the use of knowledge and skills as determinants of board control and advisory task performance. Further, we consider how two different institutional settings influence board tasks, and how the context moderates the relationship between processes and tasks. Our hypotheses are tested on a survey‐based dataset of 535 medium‐sized and large industrial firms in Italy and Norway, which are considered to substantially differ along legal and cultural dimensions. The findings show that: (i) Board processes have a larger potential than demographic variables to explain board task performance; (ii) board task performance differs significantly between boards operating in different contexts; and (iii) national context moderates the relationships between board processes and board task performance. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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The Norwegian Integrated Land Use and Transport Planning Scheme TP10 was launched in 1991 as a responseto growing concern about the environmental effects of road transport in Norway's largest cities. Its main goal was to develop transport and land use policies leading to reductions in the growth of car use and transport demand. The purpose of this paper is to explain and discuss why the scheme on the whole failed to produce the intended policies. One reason was that the planning process in the scheme was dominated by the traditional transport planning and implementation authorities. The scheme was also linked to the national roads planning process in a way which diverted TP10 from its stated environmental goals. The paper concludes that radical changes in existing policies should be accompanied by institutional reform.  相似文献   
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