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241.
生态环境的恢复与建设是我国西部大开发的首要任务.在保护生态、改善环境、发展经济的过程中,要特别重视退耕还林(草)等对保护西部生态环境的作用.我们要根据<全国生态环境建设规划>以及可持续发展的要求,采取相应的对策.  相似文献   
242.
Studying dipterans at the scene of a death can provide essential information for interpreting the evidence and help to reconstruct the events happened to a corpse in the past. Molecular tools have been employed for identification at specific levels in the cases of cryptic species or poorly conserved specimens. Identification of specimens is essential in forensic entomology since each species has a specific growth rate, which determines the calculation of the minimum post mortem interval (minPMI). In addition, phylogeographic reconstruction within a species can help to differentiate the haplotypes from a geographic area, thereby helping to clarify the possible relocation of a corpse. The morphological identification of Sarcophagidae species is often difficult, especially for the females. This is an important Diptera family since some of its species are among the first to reach a corpse, especially in warm areas. In this study, we compared the sarcophagids found in human corpses in forensic cases in Alicante (southeast of Spain) with specimens collected from baited traps in the same area and surrounding provinces. In total, 189 specimens were collected, comprising 72 from forensic cases and 117 from baited traps. Molecular identification was conducted by sequencing the cox1 mitochondrial gene and analyzing the sequences using ABGD, GMYC, and BIN species delimitation methods. The median joining algorithm in the PopART program was used to construct phylogeographic networks. Eight species in the family Sarcophagidae were identified. The most widely collected species were Sarcophaga argyrostoma and Sarcophaga tibialis. The haplotype networks obtained for these species did not indicate a clear geographic distribution of haplotypes. The S. argyrostoma samples from Alcoy were clearly isolated. The results demonstrated that this method is useful for identifying Sarcophagidae samples in forensic investigations and it can be employed for minPMI estimation.  相似文献   
243.
目的尸体角膜随死后时间延长发生的形态学变化是规律性较好的指标,常用来判断死亡时间(postmortem interval,PMI)。本文尝试用机器视觉代替人的肉眼主观判断,收集尸体样本以建立通过人体角膜图像推断PMI的模型。方法收集实际案例建立包含505例人体死后角膜图像的数据库,PMI范围为0.24h(约死后14min)至492h(约死后20.5d),大致分为三类(依次为:0~<6h、6~<20h、20h及以上)或二类(0~<15h、15h及以上);使用由华盛顿大学陈天奇博士提出的Xgboost模型分别进行二分类与三分类分析;使用多种卷积神经网络模型分别进行分类和回归学习,并通过比较最终选择了由微软研究院提出的ResNet模型进行分析。结果Xgboost在三分类时预测准确率依次为71.8%、40.7%、65.7%,二分类时为90%、48.5%。ResNet分类模型中,精准率、召回率在三分类时分别依次为:81%、75%,30%、50%,61%、71%,二分类时为:70%、92%,76%、38%。ResNet回归模型中,比较整个模型的预测结果,0~6h内的预测值与真实值较为接近,均值误差为0.5616,均方误差为0.5873,6h之后开始出现较大误差。结论分类和回归模型都在0~6h之内得到了很好的结果,说明在此时间段内,角膜图像噪声较低,可预测性强。  相似文献   
244.
Intractable international conflicts and difficult or intractable family conflicts have much in common. Relationships are damaged or destroyed, escalation causes parties to become polarized and make bad decisions, communication is strained or nonexistent, and competition and coercion take the place of collaboration. Similarities also exist in the realm of solutions, and those caught in (or intervening in) difficult family conflicts can learn much from the strategies and tactics of international peacebuilders. This article describes eight steps that peacebuilders at both the family level and the international level can take to make very damaging conflicts more constructive.
    Key Points for the Family Court Community:
  • Limiting escalation is important in both contexts.
  • Preventing or correcting misunderstandings is key to resolution in both contexts as well.
  • Be sure you are focusing on the real problem(s).
  • Get the facts straight (and agreed upon) before making agreements.
  • Healing past wrongs is important for long term stability.
  • Working both within and beyond the zone of possible agreement (ZOPA) is essential in both contexts.
  • Working to improve relationships helps all parties and improves the outcome.
  相似文献   
245.
Traditional food supply systems, like municipal public markets (MPM), are in crisis. Nevertheless, MPMs continue to demonstrate importance in the lives of the cities. In this article we discuss the case of Mexico City and the importance of the public markets for its neighbourhoods. We present the results of two research projects, completed in Mexico City at two different historical times and interpreted longitudinally. The results demonstrate the importance of socio-economic relationships for MPM's survival and potential. The article concludes with public policy recommendations to permit conservation, given the MPM's importance for the city's social cohesion.  相似文献   
246.
Farmer-to-farmer extension (FFE) is playing a complementary role to formal extension services in facilitating the spread of agricultural technologies and improving farmers’ capacities. The effectiveness and sustainability of such programmes depend on volunteer farmer trainers (VFTs) having technical skills and overcoming process-related challenges that hinder them from achieving the desired outcomes. This article uses quantitative and qualitative data collected from seven sites to explore the challenges experienced by VFTs as they share their knowledge on livestock feed innovations in a dairy development project in Kenya. Sustainable opportunities for enhancing VFTs’ performance are discussed.  相似文献   
247.
Concerns about the decline of rural agricultural communities have recently refocused on new economic opportunities available in regional food production. This article analyses three on-the-ground case studies of rural development projects in Tasmania, Australia that aimed to develop new regional food opportunities. It analyses these projects to identify how local food producers can create viable economic alternatives in rural settings. The projects illustrate that the existence of regional food assets alone is not enough to guarantee economic development success: rural producers need connections into relevant knowledge networks if they are to identify and respond to new agro-food market opportunities.  相似文献   
248.
While substantial literature is available on the determinants of small-scale farmers’ participation in collective action, and the welfare impacts of producing and/or marketing collectively, studies on the likely implications of organisational form on producers’ collective behaviour remain scant. This article attempts to address this knowledge gap by using an example of different forms of small-scale mushroom-producing groups in Swaziland. Given the importance of collective action in sub-Saharan Africa, the overall results of this article provide valuable insights into alternative means of coordinating commercial small-scale agricultural activities, which can improve producers’ ultimate benefits while reducing the likelihood of internal free-riding.  相似文献   
249.
In the process of urbanisation villages are becoming parts of cities or towns, and are becoming almost irreversibly transformed as a result. Erstwhile villages, now parts of cities and towns, are on the margins of an urbanising India. They are lagging behind other parts of the cities in terms of receiving basic urban services and infrastructures. Urban development processes should look at the specific issues and concerns of these villages independently from the need and scope of planning for the city at large. This would make the transition from rural to urban status fair and inclusive for erstwhile villagers.  相似文献   
250.
This article describes a collaborative research for development project that used participatory methods to engage smallholder farmers in Uganda in post-harvest aflatoxin management. It is based primarily on qualitative research with peanut growers tracing ‘the path of the peanut’ through their hand-drawn maps and journal writing. By focusing on everyday life and including recipes and drawings, this research encouraged women's participation and emphasised women's roles. A unique partnership among universities, women's organisations, and farmers created an environment of mutual learning and produced a book documenting food preparation and other post-harvest practices as part of a study and capacity-building effort on peanuts and aflatoxins.  相似文献   
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