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91.
Virgin female cabbage butterflies, Pieris rapae crucivora, accept and mate with courting males, whereas mated females reject them and assume the “mate refusal posture”. This study
tested whether the biogenic amines, serotonin (5HT), dopamine (DA), and octopamine (OA), were responsible for this change
in behavior. The results showed that 2–3-day-old virgin females fed with 5HT rejected courting males significantly more frequently
compared with controls fed on sucrose. In contrast, the proportions of courting males rejected by virgin females fed with
either DA or OA did not differ from sucrose-fed controls. Oral application of each amine resulted in significantly increased
levels of the amine applied (or its metabolite) in the brain. The results strongly suggest that 5HT or a 5HT metabolite may
be responsible for the post-mating change in behavioral response of 2–3-day-old virgin females to courting males. Similar
effects of 5HT treatment were observed in 6–8-day-old virgin females, but in this case the results were only marginally different
from the controls, suggesting that the effect may decline with increasing female age. 相似文献
92.
Thai Hong Nam Nguyen Tien Dung Nguyen Van Tuan Nguyen Hoang Giang Kawamoto Ken 《Journal of Material Cycles and Waste Management》2022,24(1):34-48
Journal of Material Cycles and Waste Management - Mechanical properties of recycled concrete aggregates (RCA) such as compaction and California bearing ratio (CBR) are important for application as... 相似文献
93.
Featured Collection Introduction: Connectivity of Streams and Wetlands to Downstream Waters
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Laurie C. Alexander Ken M. Fritz Kate A. Schofield Bradley C. Autrey Julie E. DeMeester Heather E. Golden David C. Goodrich William G. Kepner Hadas R. Kiperwas Charles R. Lane Stephen D. LeDuc Scott G. Leibowitz Michael G. McManus Amina I. Pollard Caroline E. Ridley Melanie K. Vanderhoof Parker J. Wigington Jr. 《Journal of the American Water Resources Association》2018,54(2):287-297
Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees of aquatic ecosystem connectivity presents challenges for researchers and managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, and biological processes. However, protecting natural gradients of connectivity is key to protecting the range of ecosystem services that aquatic ecosystems provide. In this featured collection, we review the available evidence on connections and functions by which streams and wetlands affect the integrity of downstream waters such as large rivers, lakes, reservoirs, and estuaries. The reviews in this collection focus on the types of waters whose protections under the U.S. Clean Water Act have been called into question by U.S. Supreme Court cases. We synthesize 40+ years of research on longitudinal, lateral, and vertical fluxes of energy, material, and biota between aquatic ecosystems included within the Act's frame of reference. Many questions about the roles of streams and wetlands in sustaining downstream water integrity can be answered from currently available literature, and emerging research is rapidly closing data gaps with exciting new insights into aquatic connectivity and function at local, watershed, and regional scales. Synthesis of foundational and emerging research is needed to support science‐based efforts to provide safe, reliable sources of fresh water for present and future generations. 相似文献
94.
95.
Previous lead (Pb) exposure studies identified the Michelena sector in Valencia as a ‘critical’ area for Pb contamination. An analytical-ecological study was designed to evaluate the association of environmental and nutritional variables with blood lead (BPb) in children attending two schools located in this sector. A questionnaire was administered and the findings were correlated with BPb and serum-calcium (S-Ca) levels. The total population examined included 60 children (4–9 years old). The mean BPb values was 10.5?±?3?ug/dL (61.7%?≥?10?ug/dL) and the mean S-Ca was 8.9?±?0.7?mg/dL. A significant difference (p?=?0.042) was found between BPbs in males (11.1?±?3.1?ug/dL) when compared with females (9.6?±?2.8?ug/dL). Child age, school, schedule at school, parents' occupational exposure, habits, and socioeconomic status had no significant association with BPbs. The relationship between BPb levels (dependent variable) and the S-Ca and daily Ca intake levels (independent variables) was analysed through multiple regression analysis. The results show an inverse relationship between BPb and both variables (β?=??0.073, and β?=??0.001) respectively, with the daily Ca intake being the only significant variable in the model (p?=?0.04). Although average BPbs was not very high, the percentage of children with BPbs higher than the US-CDC intervention level was greater than those found in other studies. Since detailed information is generally unavailable for these children in Venezuela, this study provides insights for future research. 相似文献
96.
Ken USHIJIMA Mitsuteru IRIE Neni SINTAWARDANI Jovita TRIASTUTI Umi HAMIDAH Tadaharu ISHIKAWA Naoyuki FUNAMIZU 《Frontiers of Environmental Science & Engineering》2013,7(1):120-126
Material flow analysis (MFA) and value flow analysis (VFA) were applied to the sanitation system in an urban slum in Indonesia. Based on the results of the MFA and VFA, garbage and excreta disposal costs were evaluated to be 0.7% and 1.1%, respectively, of per capita income. Such value flows seem reasonable in light of the recognized affordability to pay (ATP) standard. However, current excreta disposal methods create negative impacts on downstream populations. Because such disadvantages do not go back to disposers, but passed to downstream, the current value flow structure does not motivate individual toilet users to install treatment facility. Based on current material and value flow structures, a resource recycling sanitation system scenario was examined. Based on VFA, an affordable initial cost for such a system was calculated; this was found to be comparable in price to a cheaper composting toilet that is currently available in the market. 相似文献
97.
J Sun A Rojas P Bertrand Y Petit R Kraenzler PJ Arnoux 《Traffic injury prevention》2012,13(5):519-528
Objective: With 16 percent of the total road user fatalities, motorcyclists represent the second highest rate of road fatalities in France after car occupants. Regarding road accidents, a large proportion of trauma was on the lower cervical spine. According to different clinical studies, it is postulated that the cervical spine fragility areas are located on the upper and lower cervical spine. In motorcycle crashes, impact conditions occur on the head segment with various orientations and impact directions, leading to a combination of rotations and compression. Hence, motorcyclist vulnerability was investigated considering many impact conditions. Method: Using the human model for safety (HUMOS), a finite element model, this work aims to provide an evaluation of the cervical spine weaknesses based on an evaluation of injury mechanisms. This evaluation consisted of defining 2 injury risk factors (joint injury and bone fracture) using a design of experiment including various velocities, impact directions, and impact orientations. Results: The results confirmed previously reported clinical and epidemiological work on the fragility of the lower cervical spine and the upper cervical spine segments. Joint injuries appeared before bone fractures on both the upper and lower cervical spine. Bone fracture risk was greater on the lower cervical spine than on the upper cervical spine. The compression induced by a high impact angle was identified as an important injury severity factor. It significantly increased the injury incidence for both joint injuries and bone fractures. It also induced a shift in injury location from the lower to the upper cervical spine. The impact velocity exhibited a linear relationship with injury risks and severity. It also shifted the bone fracture risk from the lower to upper spinal segments. 相似文献
98.
Integrated biogeochemical modelling of nitrogen load from anthropogenic and natural sources in Japan
Bin He Taikan Oki Shinjiro Kanae Goro Mouri Ken Kodama Daisuke Komori Shinta Seto 《Ecological modelling》2009
This study proposed an integrated biogeochemical modelling of nitrogen loads from anthropogenic and natural sources in Japan. Firstly, the nitrogen load (NL) from different sources such as crop, livestock, industrial plant, urban and rural resident was calculated by using datasets of fertilizer utilization, population distribution, land use map, and social census. Then, the nitrate leaching from soil layers in farmland, grassland and natural conditions was calculated by using a terrestrial nitrogen cycle model (TNCM). The Total Runoff Integrating Pathways (TRIP) was used to transport nitrogen from natural and anthropogenic sources through river channels, as well as collect and route nitrogen to the river mouths. The forcing meteorological and hydrological data is a 30-year (1976–2005) dataset for Japan which were obtained by the land surface model, Minimal Advanced Treatments of Surface Interaction and Runoff (MATSIRO). For the model validation, we collected total nitrogen (TN) concentration data from 59 rivers in Japan. As a comparison result, calculated TN concentration values were in good agreement with the observed ones, which shows the reliability of the proposed model. Finally, the TN loads from point and nonpoint sources were summarized and evaluated for 59 river basins in Japan. The proposed modelling framework can be used as a tool for quantitative evaluation of nitrogen load in terrestrial ecosystems at a national scale. The connection to land use and climate data provides a possibility to use this model for analysis of climate change and land use change impacts on hydrology and water quality. 相似文献
99.
We introduce a new index for measuring perpendicularity of animal movements with respect to a boundary (e.g., a habitat patch edge), and provide a computer algorithm for its calculation. Our index, η, improves on an approach that measures perpendicularity with respect to a fixed boundary direction. This is because η accounts for moment-to-moment trajectories relative to nearest-neighbor boundary attributes at the scale of an animal's movement. Our algorithm prp calculates η efficiently and accurately with both synthetic data and large telemetry datasets. In addition, we have included routines in prp which account for scenarios inherently problematic to perpendicularity estimators. 相似文献
100.
运行方式对人工快渗系统水质净化效果的影响 总被引:1,自引:0,他引:1
以天然砂作为主要渗滤介质,建立污水处理人工快速渗滤系统(CRI).分别以洗浴污水、生活污水和受污染河水作为研究对象,在相同的水力负荷条件下,用两种不同的运行方式(定期投配一定量的污水、淹水和落干交替运行)对不同水质的污染物去除效果进行了对比研究.结果表明,通过缩短淹水周期,加大系统淹水和落干的频率,可以明显改善CRI系统的污染物去除效果. 相似文献