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61.
Chinstrap, Pygoscelis antarctica, and gentoo, P. papua, penguins are sympatric species that inhabit the Antarctic Peninsula. To evaluate differences in the foraging habitat of these two species, we recorded their foraging locations and diving behavior using recently developed GPS-depth data loggers. The study was conducted on King George Island, Antarctica during the chick-guarding period of both species, from December 2006 to January 2007. The area used for foraging, estimated as the 95% kernel density of dive (>5 m) locations, overlapped partially between the two species (26.4 and 68.5% of the area overlapped for chinstrap and gentoo penguins, respectively). However, the core foraging area, estimated as the 50% kernel density, was mostly separate (12.8 and 25.0% of the area overlapped for chinstrap and gentoo penguins, respectively). Chinstrap penguins tended to use off-shelf (water depth > 200 m) regions (77% of the locations for dives >5 m), whereas gentoo penguins mainly used on-shelf (water depth < 200 m) areas (71% of dive locations). The data on foraging locations, diving behavior, and bathymetry indicated that gentoo penguins often performed benthic dives (28% of dives >5 m), whereas chinstrap penguins almost always used the epipelagic/mid-water layer (96% of dives >5 m). Diving parameters such as diving bottom duration or diving efficiency differed between the species, reflecting differences in the use of foraging habitat. The diving parameters also suggested that the on-shelf benthic layer was profitable foraging habitat for gentoo penguins. Conversely, the relationship between trip duration, date, and stomach content mass suggested that the chinstrap penguins went further from the colony to forage as the season progressed, possibly reflecting a reduction in prey availability near the colony. Our results suggest that chinstrap and gentoo penguins segregated their foraging habitat in the Antarctic coastal marine environment, possibly due to inter- and intra-specific competition for common prey resources.  相似文献   
62.
63.
Proper management and evaluation of environmental effects for coastal groundwater aquifers require accurate estimation of salt and fresh water movement. For this we compare two numerical methods to study saltwater intrusion. The two numerical methods are the CIP (constrained interpolation profile) and the MOC (method of characteristics). The two numerical methods are used to solve the salt transport equation. The two methods are applied and compared to saltwater intrusion experiments for confined and unconfined aquifer case studies. It is found that for both cases, the CIP-method is superior in terms of calculation time while keeping an acceptable numerical accuracy.  相似文献   
64.
日本的医疗垃圾处理系统   总被引:2,自引:0,他引:2  
由于医疗垃圾具有较强的感染性,所以日本在法律上规定禁止其回收再利用,必须进行彻底销毁处理。文章介绍了日本的医疗卫生单位垃圾的分类,处理过程,对策及法律制度,为中国医疗垃圾处理业的顺利发展提供借鉴。使之尽快形成一个完整的运行体系。  相似文献   
65.
In the post-genome-sequencing era, emerging genomic technologies are shifting the paradigm for drug discovery and development. Nevertheless, drug discovery and development still remain high-risk and high-stakes ventures with long and costly timelines. Indeed, the attrition of drug candidates in preclinical and development stages is a major problem in drug design. For at least 30% of the candidates, this attrition is due to poor pharmacokinetics and toxicity. Thus, pharmaceutical companies have begun to seriously re-evaluate their current strategies of drug discovery and development. In that light, we propose that a transport mechanism-based design might help to create new, pharmacokinetically advantageous drugs, and as such should be considered an important component of drug design strategy. Performing enzyme- and/or cell-based drug transporter, interaction tests may greatly facilitate drug development and allow the prediction of drug–drug interactions. We recently developed methods for high-speed functional screening and quantitative structure–activity relationship analysis to study the substrate specificity of ABC transporters and to evaluate the effect of genetic polymorphisms on their function. These methods would provide a practical tool to screen synthetic and natural compounds, and these data can be applied to the molecular design of new drugs. In this review article, we present an overview on the genetic polymorphisms of human ABC transporter ABCG2 and new camptothecin analogues that can circumvent AGCG2-associated multidrug resistance of cancer.  相似文献   
66.
Total mercury intake from fish and shellfish by Japanese people   总被引:4,自引:0,他引:4  
Elevated mercury concentrations have been reported in fish in recent years. Japanese people eat a great deal of raw fishes and shellfishes as “Sashimi” and “Sushi”. The action level of large predatory fish such as tuna with total mercury levels exceeding the Japanese maximum permitted limit of 0.4 ppm is exempted from regulation in Japan. Therefore, current total mercury intake from fish and shellfish of Japanese people is unknown. The purpose of this investigation was to estimate the total mercury intake from fish and shellfish. It was found that the mean total mercury concentration of 1.11 ppm in tuna of eatable base as Sashimi or Sushi was clearly higher than the normal level. The mean total mercury intake from fish and shellfish was 0.17mg per capita per week . According to the hypothesis that 75% of total mercury in fish and shellfish is methylmercury, the weekly intake of 0.13 mg as methylmercury was corresponding amount to about 74% of provisional tolerable weekly intake 0.17 mg of methylmercury set by the Welfare Ministry of Japan.  相似文献   
67.
Elevated levels of CO2 in the atmosphere have been linked to the rise in land and sea temperature [Climate Change, 2001. In: Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J., Xiaosu, D. (Eds.), The Scientific Basis Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Cambridge University Press, UK, p. 944]. To demonstrate geological carbon sequestration as a mitigation technique, a carbon dioxide injection experiment was conducted in East Texas. The target – Frio formation – is a highly porous, permeable and unconsolidated sandstone. The specific interval is the Frio C sand, which originally was saturated with saline formation water. At the injection location, the Frio C sand dips 18° to the south. To monitor the injected CO2 spreading in the formation, an old well from 1956 drilled into the deeper Yegua formation was selected as the observation well. The injection well was drilled at a distance of 100 ft downdip from the monitoring well. Several borehole measurement methods were available to monitor the CO2 injection, but the most suitable technology was thought to be the pulsed neutron logging. This logging is used widely in cased hole, and the measured macroscopic thermal absorption cross-section (Σ) is sensitive to CO2 saturation in high porosity saline water environments. Several log examples are given demonstrating successful the monitoring of the CO2 plume moving through the two boreholes and the resulting saturation changes.  相似文献   
68.
A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in human feces. Therefore, care should be taken when handling the sawdust. It should also be noted that pathogenic viruses tend to have stronger tolerance than pathogenic bacteria. The fates of several species of coliphages, T4, , Q and MS2, in sawdust were investigated as a viral model. The fates of coliphages were significantly different among them, and they changed in response to temperature and the water content of the sawdust. As the results, T4 coliphage had the strongest tolerance and Q had the weakest one in sawdust. It was estimated the days required to decrease virus to a safe level based on a risk assessment. According to the rates of Q and T4, 15 days and 167 days were required respectively for a safe level of infection risk based on actually operated composting toilet condition. Thus, it was significantly different depending on the species and sawdust conditions.  相似文献   
69.
城市大气颗粒物污染和致敏花粉的污染已经对人群健康和城市空气质量产生了较为严重的影响.这2种污染物的协同生物效应正在成为大气环境科学、环境毒理学、免疫学等学科研究的前沿和热点研究领域.以上海大气中的细/超细颗粒物和日本关东地区致敏花粉(柳杉)为例,阐述了大气细/超细颗粒物的表征以及花粉致敏的过程.在研究中,观察到了日本柳杉花粉壁附着有直径0.7μm的含变应原蛋白的微粒(Ubisch body),并用ELISA法揭示了日本关东地区大气颗粒物中含变应原蛋白的颗粒主要分布在1μm的粒径范围内;而在上海大气颗粒物中,化学元素总量的最大值出现在细/超细粒径颗粒物(0.3~0.18μm)范围,污染元素S和Pb的质量浓度在超细(纳米尺度)/细颗粒物中比在其他粒径范围颗粒物中要高,另外还发现在上海大气颗粒物中有植物花粉的存在.城市大气颗粒物中的主要组分,柴油机车尾气颗粒物(DEPs)与飞散花粉之间存在协同生物效应,但其机制和过程还不清楚,在最新研究成果的基础上并结合国内外相关研究领域的进展,对飞散花粉与大气细/超细颗粒物的协同生物效应的研究进行了总结并提出今后研究的方向.  相似文献   
70.

The first draft scenario toward net zero greenhouse gas (GHG) emissions by 2050 for the material cycles and waste management sector was presented by the Ministry of the Environment, Japan in August 2021. The details of the future GHG emission estimation used to create the draft scenario are described in this document. For multiple scenarios where more aggressive measures, such as carbon capture, utilization, and storage (CCUS), were included in addition to business-as-usual and the current policy continuity scenario, future GHG emissions were estimated as the sum of the products of activities and emission factors indicating changes in measures between scenarios. The estimation outcomes demonstrated that future GHG emissions from the solid waste management sector could be anticipated to be zero or even negative when material conversion to biomass, primarily for plastics, recycling to raw materials, and installation of CCUS at incineration facilities are assumed. Extensions of prior plans are not enough to reach the goal of net zero emissions, according to the measures necessary and the volume and pace of their implementation suggested in this study. Stakeholders should collaborate with great ambition.

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