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1.
 The reproductive biology of female Penaeus japonicus Bate was investigated in the Ariake Sea and Tachibana Bay (located outside the Ariake Sea), Japan from 1994 to 1996. Interannual, seasonal, individual female body size and spatial influences on the incidence of spawning were examined. The proportion of inseminated females, increased with increasing body size up to 170 mm body length (BL) and decreased thereafter. The minimum size at maturity was similar between years; 130 to 140 mm BL. The minimum size of individuals with developing ovaries or spermatophores differed from that of ripe females by 20 to 25 mm. Spawning occurred in the central part of the Ariake Sea and Tachibana Bay but rarely in the inner part. P. japonicus had a clear reproductive cycle. Spawning started earlier and ended later, occurring from mid-May to mid-October, in the eastern central part of and outside of the Ariake Sea compared with the western central part, where spawning occurred from mid-June to mid-September. Spawning dynamics differed across seasons, body sizes and areas but not across years. The seasonal peak in the proportion of ripe females varied with body size. In small individuals (130 to 169 mm BL), no peak was observed, whereas in large individuals (>170 mm BL) the proportion of ripe individuals peaked in June. The proportion of ripe individuals increased with increasing body size and was high outside the Ariake Sea. Factors causing the variation in spawning dynamics are discussed. Received: 30 November 1998 / Accepted: 12 October 1999  相似文献   
2.
Throughout Asia, rapid and uncontrolled urbanization has created serious environmental problems, and the development of sustainable urban–rural planning methods is of critical importance. To improve our understanding of mixed urban–rural land uses and provide future practical visions for regional planning, we conducted a case study of the urban fringe of the Bangkok Metropolitan Region, Thailand. After identifying local irrigation districts as the basic spatial unit for resource circulation, we quantified current material flows of organic wastes generated by households within each district. We then developed two different land-use scenarios for 2020: (1) a high-rise compact and (2) a low-story sprawl development scenario. These scenarios were compared in terms of efficiency of material flows and energy consumption. We found that, based on current infrastructure and technology, the latter scenario was more advantageous in terms of both material input and energy consumption than the former, thereby, identifying positive aspects of urban–rural land-use mixture. Based on these results, we propose that planners should focus on density control measures that take into account bioresource circulation within irrigation districts rather than simply drawing arbitrary land-use zoning lines. To this end, we suggest that the division between agricultural and urban planning departments must be bridged, and that research should take an interdisciplinary approach.  相似文献   
3.
Sustainability principles are at the forefront of regional planning. In Hawaii, the movement toward “sustainability” gave way to revisiting the State Plan. This paper uses a case study of the Hawaii 2050 Sustainability Plan (Hawaii 2050) to illustrate how adopting popular notions of sustainability, without critical examination of how the respective policy frames diverge or interrelate, can lead to “tautological traps.” In the case of Hawaii 2050, the “triple-bottom-line” (embedded within sustainable development) became the dominant sustainability frame during the solicitation of public input and was thus used to guide the planning discourse. The application of triple-bottom-line concepts at the level of policy and planning led to a process that polarized economic and environmental interests. While the goals of sustainable development and the use of triple-bottom-line concepts are useful for planners, we argue that they should be applied within the parameters of ecological sustainability in a US regional context, lest resulting plans continue to allow the momentum of development to override ecological concerns.  相似文献   
4.
Little information on the evaluation of airborne particulate matter (APM) and sedimentation particles from subway stations is available. The thermal metamorphism of train wheels generating toxic particles in subway stations is a possibility. In this study, the toxicity and physiological effects of particles from subway stations were evaluated using a yeast bioassay system. Estrogenic and antiestrogenic activities of APM in APM extracts from subway stations were determined. No estrogenic activity was found in the APM fractions and their S9-activated APM samples. Sedimentation dust samples also showed no estrogen activity. In contrast, extracts from sedimentation dust samples showed antiestrogen activity. Marked yeast toxicity was observed in the samples extracted from sedimentation dust. Potent yeast toxicity was also found in the S9-activated extracts from sedimentation dust. The results suggest that sedimentation dust from a semiclosed area of a subway system has antiestrogen activity, although both the origin and generation system of this activity are uncertain. These pollutants in sedimentation dust may change to a more toxic form in vivo by S9 activation.  相似文献   
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6.
The challenge for sustainability educational programs lies in how to imbue students with the strong motivation necessary to move the world in a more sustainable direction. Five universities in Japan have mutually collaborated in the design and development of a unique curriculum and education system for sustainability science since 2008. Specifically, they have developed a common and remote lecture system called the “Frontier of sustainability science” (FSS). This paper discusses the concepts and challenges of FSS and how it was organized to teach students to actively learn how to work with people of various disciplines to realize interdisciplinarity.  相似文献   
7.
The 2005 hurricane season caused extensive damage and induced a mass migration of approximately 1.1 million people from southern Louisiana in the United States. Current and accurate estimates of population size and demographics and an assessment of the critical needs for public services were required to guide recovery efforts. Since forecasts using pre-hurricane data may produce inaccurate estimates of the post-hurricane population, a household survey in 18 hurricane-affected parishes was conducted to provide timely and credible information on the size of these populations, their demographics and their condition. This paper describes the methods used, the challenges encountered, and the key factors for successful implementation. This post-disaster survey was unique because it identified the needs of the people in the affected parishes and quantified the number of people with these needs. Consequently, this survey established new population and health indicator baselines that otherwise would have not been available to guide the relief and recovery efforts in southern Louisiana.  相似文献   
8.
Airborne bacteria were measured when a dust storm passed Beijing in spring 2012 with a focus on cell concentration,viability and TSA-and R2A-cultured strain composition.The concentration varied at an order of 10~7 cells/m~3 with dust loading(demonstrated with PM_(10))and they had a very close correlation(R_T~2 = 0.91,p 0.01).At the time of highest PM_(10) of652 μg/m~3,the bacterial concentration reached 1.4 × 10~8 cells/m~3,which was larger than that before and after the dust event by one order.Bacterial viability,the ratio of number concentration of viable cells to total cells,was 32%-64%and smaller in the dust plume than that before the dust arrival.Bacterial strains from the culture ranged between 2.5 x 104 and4.6×10~5 CFU/m~3 and no correlation with PM_(10) was determined.Their composition was different before and after the dust arrival according to 16SrRNA gene sequences and strains belong to Actinomycetes and Firmicutes were the majority in the dust samples.  相似文献   
9.
We found a significant geographic gradient (longitudinal and latitudinal) in the sulfate (SO42?) concentrations measured at multiple sites over the East Asian Pacific Rim region. Furthermore, the observed gradient was well reproduced by a regional chemical transport model. The observed and modeled SO42? concentrations were higher at the sites closer to the Asian continent. The concentrations of SO42? from China as calculated by the model also showed the fundamental features of the longitudinal/latitudinal gradient. The proportional contribution of Chinese SO42? to the total in Japan throughout the year was above 50–70% in the control case, using data for Chinese sulfur dioxide (SO2) emission from the Regional Emission Inventory in Asia (40–60% in the low Chinese emissions case, using Chinese SO2 emissions data from the State Environmental Protection Administration of China), with a winter maximum of approximately 65–80%, although the actual concentrations of SO42? from China were highest in summer. The multiple-site measurements and the model analysis strongly suggest that the SO42? concentrations in Japan were influenced by the outflow from the Asian continent, and this influence was greatest in the areas closer to the Asian continent. In contrast, we found no longitudinal/latitudinal gradient in SO2 concentrations; instead SO2 concentrations were significantly correlated with local SO2 emissions. Our results show that large amounts of particulate sulfate are transported over long distances from the East Asian Pacific Rim region, and consequently the SO42? concentrations in Japan are controlled by the transboundary outflow from the Asian continent.  相似文献   
10.
Dichlorodiphenyltrichloroethane (DDT) is one of the persistent organic pollutants (POPs) widely found in the environment and in the general population. In this study, a direct competitive enzyme immunoassay (EIA) has been developed for the quantitative analysis of DDT. To generate a specific polyclonal antibody for EIA, p, p′-DDT was conjugated to porcine thyroglobulin for rabbit immunization. At optimized EIA conditions, the standard curves ranged from 0.137 to 100 ng/mL with the quantification limit of 0.41 ng/mL. The coefficients of variation (CV%) were 5.42–10.53% for intra-assay and 6.04–7.26% for inter-assay. Cross-reactivities with DDT metabolites (DDTs, including o, p′-DDT, p, p′-DDD, o, p′-DDD, p, p′-DDE, o, p′-DDE, p, p′-dichlorobenzophenone (DCBP), o, p′-DCBP) were investigated. The polyclonal antibody showed relatively low and/or no cross-reactivity with these compounds, and the assay was seen to be highly selective for p, p′-DDT. Moreover, the DDTs could be ranked by their reactivity: DDT > DDD > DDE > DCBP. In addition, the characterization of the polyclonal antibody indicated that the antiserum possesses a high specificity for p, p′-isomers. The results indicated that the developed EIA using this antibody could be a convenient and supplemental analytical tool for monitoring DDT.  相似文献   
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