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121.
Tail autotomy incurs energetic costs, and thus, a trade-off in resource allocation may lead to compromised immunity in lizards. We tested the hypothesis that tailless lizards will favor constitutive innate immunity responses over an energetically costly inflammatory response. The influence of fasting and colorful ornamentation was also investigated. We experimentally induced tail autotomy in the lizard Eutropis multifasciata and found that inflammation was suppressed by tail loss, but not further affected by fasting; the suppressive effect of colorful ornamentation was manifested only in males, but not in females. Constitutive innate immunity was not affected by any of these factors. As expected, only costly inflammation was compromised, and a less expensive constitutive innate immunity might be favored as a competent first-line defense during energetically demanding periods. After considering conventional trade-offs among tail regeneration and reproduction, further extending these studies to incorporate disease risk and how this influences escape responses to predators and future reproduction would make worthwhile studies.  相似文献   
122.
利用海藻酸钠作为包埋剂对苯系物细胞传感器Pseudomonas fluorescens A506(pTS)进行固定化处理,并对细胞浓度、固定化时间、投加量等检测因素进行了优化.固定化后的细胞与游离细胞对苯系污染物的检测效果进行对比.经过2 h固定化处理的细胞传感器,在检测时间1.5~6.0 h内,信号上升速度为游离细胞的2.26倍,信号最大值为游离细胞的2.23倍.固定化处理后的细胞生长缓慢,且浓度远低于游离细胞,说明了固定化处理后的单位细胞信号强度增加.同时,细胞浓度随着固定化时间的延长而降低.在影响因素方面,细胞浓度和固定化时间对于检测信号的影响较大.固定化后,对高浓度的苯系污染物有着更快的信号响应.  相似文献   
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Environmental Science and Pollution Research - The present study aimed to explore the opportunities for the sustainable development of professional sports enterprises and events from the...  相似文献   
124.
In recent years, with the raising of awareness in environmental protection and sustainable development in enterprises, the green issue has become more and more critical in supply chain management. This study intends to develop a green supplier selection model which integrates artificial neural network (ANN) and two multi-attribute decision analysis (MADA) methods: data envelopment analysis (DEA) and analytic network process (ANP). It is called ANN–MADA hybrid method. ANN–MADA hybrid method considers both practicality in traditional supplier selection criteria and environmental regulations. It also overcomes traditional DEA drawbacks, limitations of data accuracy and decision-making units (DMUs) amounts constraint. The model evaluation results of an international well-known camera manufacturer indicate that the ANN–MADA hybrid method outperforms two other hybrid methods, ANN–DEA and ANP–DEA. It was also discovered that ANN–MADA has better power of discrimination and noise-insensitivity in evaluating green suppliers’ performances.  相似文献   
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Fetal cells were enriched from maternal blood using density gradient centrifugation of Histopaque followed by magnetic-activated cell sorting (MACS) to select CD71-positive cells. For each specimen, cells partially purified by Histopaque were split into equal portions, and each portion was subjected to purification by MACS in parallel. Cells before and after MACS were subjected to dual-color fluorescence in situ hybridization (FISH) analysis with X- and Y-chromosome-specific probes. We found that the hybridization rates were decreased by approximately 10% after MACS based on duplicated analysis for each sample. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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The objectives of this study were to determine environmental occurrence and concentrations of selected currently-used-pesticides and some transformation products in agricultural farms in the Okanagan Valley (OKV), and to conduct a simple risk assessment of environmental pesticides levels detected in OKV on non-target aquatic organisms. The OKV is the tree fruit country of the Province of British Columbia where considerable amount of pesticides are applied annually. Water, sediment and soil samples were collected at eleven sites in early June and late September following rainfall events and/or extended periods of irrigation from drainage ditches and/or from small streams. Undisturbed reference sites were also sampled. Study results showed that forty of the eighty chemicals analyzed, including organochlorine, nitrogen-containing and organophosphate pesticides commonly used for OKV crops, were detected in runoff and small stream water samples. Among which, endosulfan-sulfate was the most frequently detected chemical. Also, azinophos-methyl (0.699–25.5 ng/L), diazinon (0.088–214 ng/L) exceeded, and α-, β- endosulfan, endosulfan sulphate approached the guidelines for the protection of aquatic life.  相似文献   
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The purpose of this study is to analyse the proper factors to be contained in an evaluation system which can then be used to assess areas for designating national parks in Taiwan. In the first phase of work, the Delphi method was used to collect expert opinions on a total of 10 categories of evaluating factors. Six of them are used to assess the characteristics of a site and include diversity, representativeness,naturalness, rarity, fragility and suitability. The other four categories represent the potential for management objectives including conservation, research, education and other functions. This evaluating system will be used and examined in the second phase of our work.  相似文献   
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