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21.
We investigated the changes in temperatures in Takamatsu, Tadotsu and Osaka areas in Japan. Data of temperatures in Takamatsu (urban area: 1942-2009), Tadotsu (rural area: 1893-2009) and Osaka (metropolitan area: 1883-2009) areas around the Inland Sea in Japan was obtained from Japan Meteorological Agency. The changes in temperatures in three areas in Japan were analyzed and compared. By using data from 1942 to 2009, various parameters of temperatures were significantly correlated with years. The changes in mean temperature in August and in a year in Takamatsu area for 50 years were highest (August: 1.6°C, Year: 1.8°C) among three areas. In addition, correlation coefficient rate between years and the number of days over the level of 34°C in August in Takamatsu area was highest (r = 0.567, p < 0.0001). Parameters of temperatures were gradually increased with years in all three areas. The heat island effect in Takamatsu area was similar to Osaka area in Japan.  相似文献   
22.
2001~2003年间北京大气降水的化学特征   总被引:46,自引:1,他引:46  
为了了解北京大气降水的化学组成与时间变化特征,连续进行了2年的降雨采样与分析.在65个降雨样品中,12%的降水呈酸性;全年降水的酸度主要取决于夏季的降水.SO42-、NH4+与Ca2+是含量最丰富的组分,其平均浓度均接近或超过200礶q/L.比较分析表明,在近几年,SO42-对降水酸度的贡献显著降低,降水的硫污染特征减弱,而No3-的贡献显著增加.人为污染元素和地壳元素的浓度均在冬春季较高,在夏季最低.  相似文献   
23.
北京城区大气干沉降的水溶性离子特征   总被引:4,自引:0,他引:4       下载免费PDF全文
为了解北京城区大气干沉降中水溶性离子的化学组成与时间变化特征,连续进行了4年多的干沉降采样与分析.结果表明,在222个有效干沉降样品中,存在不同程度的阴离子缺失. SO42-与Ca2+分别是含量最丰富的阴、阳离子组分,其次是NO3-和NH4+. SO42-、NO3-和NH4+呈现相似的季节变化特征,即其浓度在夏季最高,冬季最低. 干沉降基本呈中性,其pH值月变化幅度小,但季节变化明显,夏季低而春季高.  相似文献   
24.
Environmental Science and Pollution Research - Hunting, trapping, and fishing are part of an Indigenous lifestyle in subarctic Canada. However, this lifestyle may be a route of exposure to...  相似文献   
25.
Summary Technomyrmex albipes makes huge polydomous colonies which consist of up to several millions of adults. In field colonies, dealate queens are rare or absent, though winged males and winged females emerge annually (synchronously) in large numbers from late may to mid June. Field and laboratory observations showed that the reproduction of established colonies was performed by wingless females inseminated by wingless males from the same colony. Dissections and morphological examinations revealed that wingless females are workers with no spermatheca and intercastes with a spermatheca. Most intercastes were inseminated, had developed ovaries, and seemed to reproduce, while workers did not seem to reproduce. Extranidal tasks were performed only by workers. Approximately half of the adult population were intercastes, and wingless males represented only a small portion of all adults, the rest being nonreproductive workers. Intercastes and wingless males were produced throughout the year except in winter. The winged females and males copulate outside the nest only after the nuptial flight and the dealate females are able to perform independent founding, but they are also eventually supplanted by intercastes. The adoption of dealate queens by an established natal colony did not seem to occur. Thus we infer that in this species the winged reproductives disperse and found new colonies, while inbred wingless reproductives allow the enlargement and budding of colonies. This species has a special trophic-flow system. There is no trophallaxis among adults, and nutrient transfer from adults to other colony members is achieved exclusively by specialized trophic eggs. All females (dealate queens, intercastes, and workers) seem to produce trophic eggs. This aphid-like life cycle, i.e., the occurrence of both winged and wingless reproductive forms, may have evolved as an adaptation supporting the development of secondary polygyny and polydomy.Offprint requests to: K. Yamauchi  相似文献   
26.
The bioluminescent fish Porichthys notatus (plainfin midshipman), has a discontinuous distribution along the Pacific coast of North America. The fish is present from Cape Mendocino southward to Baja California, Mexico, absent off the coast of Oregon, USA, and abundant, northward, in Puget Sound, Washington. Interestingly, the population in Puget Sound lacks the substrate (luciferin) necessary for the luminescence reaction and, despite possessing an otherwise fully functional photophore system, is nonluminescent. The California population of P. notatus is uniformly luminescent south of Monterey Bay, but 15% of the speciments tested from San Francisco Bay and the Gulf of the Farallons have been reported to be nonluminescent. Explanations for nonluminescent midshipman in both Puget Sound and the San Francisco Bay area have focussed on a dietary requirement for luciferin. To gain further insight into reasons for nonluminescence in the San Francisco Bay region, the distribution of bioluminescence in P. notatus was studied from Monterey Bay to Cape Mendocino during 1985. A complex pattern of bioluminescence was found, in which nonluminescent individuals reflected neither a local anomaly in the San Francisco Bay region nor a simple gradient of decreasing luminescence towards the northern end of the range of the California population. Instead, a distinct size-dependent component in luminescence capability of the fish was observed. Aspects of the life history of P. notatus and related factors which might influence the bioluminescence characteristics of this population are discussed.Please address all correspondence to Dr. F.I. Tsuji at the Osaka Bioscience Institute  相似文献   
27.
28.
Troodontidae is a clade of small-bodied theropod dinosaurs. A new troodontid, Gobivenator mongoliensis gen. et sp. nov., is described based on the most complete skeleton of a Late Cretaceous member of this clade presently known, from the Campanian Djadokhta Formation in the central Gobi Desert. G. mongoliensis is different from other troodontids in possessing a pointed anterior end of the fused parietal and a fossa on the surangular in front of the posterior surangular foramen. The skull was superbly preserved in the specimen and provides detailed information of the entire configuration of the palate in Troodontidae. Overall morphology of the palate in Gobivenator resembles those of dromaeosaurids and Archaeopteryx, showing an apparent trend of elongation of the pterygoid process of the palatine and reduction of the pterygopalatine suture toward the basal Avialae. The palatal configuration suggests that the skull of Gobivenator would have been akinetic but had already acquired prerequisites for later evolution of cranial kinesis in birds, such as the loss of the epipterygoid and reduction in contact areas among bones.  相似文献   
29.
Concentrations of polychlorinated naphthalene (PCN) congeners were measured in domestic animal related samples such as feed ingredients, mixed feed and animal fat. Mean concentrations of total PCNs in feed ingredients ranged from 500 to 1500 pg g(-1) lipid wt with a high concentration found in fish meal. Total PCN concentrations were similar among mixed feeds, which ranged from 98 to 110 pg g(-1) lipid wt. The total PCN concentration in chickens was more than twice the amount in pigs. Tetra-CNs were the predominant homologues in all samples. Biomagnification of higher chlorinated PCN congeners, especially penta- and hexa-CNs, was a few fold greater in chickens compared to pigs. The estimated concentrations of 2,3,7,8-tetrachloro dibenzo-p-dioxin equivalents (TEQs) of some selected PCNs in feed ingredients, mixed feeds, chickens and pigs were 0.008 to 0.063, 0.001 to 0.002, 0.033 and 0.011 pg g(-1) lipid wt, respectively. Based on predicted luciferase inducing potency for each PCN congener, the estimated PCN-TEQs in feed ingredients and animal fat were similar to those that were estimated from selected PCNs.  相似文献   
30.
Recycling is time consuming and the time available for housework may determine the intensity of recycling activities. In this study, we conducted a survey of 546 Japanese households and asked them their daily practice of five varieties of recycling activities: (1) choice of refill products, (2) use of own shopping bags, (3) sorting of recycled papers from burnable waste, (4) use of own drinking bottles when going out, and (5) use of recycle boxes prepared at the grocery store. We also asked households to record their behavior for two successive days. By combining recycling activity data and diary data, we estimate a multivariate probit model to empirically examine whether time available for housework determines the intensity of five varieties of recycling activities. The empirical result demonstrates that an individual that can allocate sufficient time for housework tends to purchase refill products. He or she also tends to bring their own shopping bags for grocery shopping. We also find that the size of house and the number of family members determine the likelihood of recycling. A housewife living with many family members in a large house is more likely to engage in time-consuming recycling activities.  相似文献   
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