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关键词： Nicrophorus americanus   American burying beetle   Gryllotalpa major   prairie mole cricket   insect conservation   PRAIRIE MOLE CRICKET   BURYING BEETLE   TALLGRASS-PRAIRIE   SAUSSURE ORTHOPTERA   OLIVIER COLEOPTERA   HABITAT LOSS   INTERFERENCE COMPETITION   CARRION BEETLES   CAPTURE RATES   BISON  

摘要： Recovery plans for rare and endangered insects most commonly focus on identifying critical abiotic habitat requirements for focal species, and then using these criteria in developing species management portfolios. Biotic interaction data are rarely available, and when produced are seldom integrated into management plans due to their complexity of interpretation. Here we examine advances in our understanding of biotic factors that regulate behavior and life history in two rare insect species of conservation focus: the carrion-breeding American burying beetle, Nicrophorus americanus (Olivier) and the lek mating Gryllotalpa major (Saussure). Current recovery and conservation plans for both species are heavily weighted by abiotic habitat considerations, despite the likely regulation of populations by critical biotic interactions such as interspecies competition, symbioses, predation, and behavioral variation. Examples presented here support a more cohesive approach to constructing conservation management plans to prioritize the integration of ecological interaction data, and to incentivize related research leading to more effective species recovery outcomes.

关键词： LIBS   PCA   Soil samples   Geothermal area   India   TRACE-ELEMENTS   MERCURY-VAPOR   SURFACE   DISCRIMINATION   CAPABILITIES   MARS  

摘要： The Manuguru geothermal area, located in the Telangana state, is one of the least explored geothermal fields in India. In this study, characterization of the soil samples is carried out by laser-induced breakdown spectroscopy (LIBS) coupled with analytical spectral-dependent principal component analysis. A total of 20 soil samples were collected both from near the thermal discharges as well as away from the thermal manifestations. LIBS spectra were recorded for all the collected soil samples and principal component analysis (PCA) was applied to easily identify the emission lines majorly responsible for variety classification of the soil samples. In this submission, a modified PCA was developed which is based on the spectral truncation method to reduce the huge number of spectral data obtained from LIBS. The PCA bi-plot on the LIBS data reveals the presence of two different clusters. One cluster represents the soil samples collected from the close vicinity of the thermal manifestations whereas the other cluster contains the soil samples collected away from the thermal sprouts. PCA performed on the chemical dataset of the soil samples also reveals the same clustering of the soil samples. Both LIBS and chemical analysis data shows that soil samples near the thermal waters are found to be enriched in B, Sr, Cs, Rb, Fe, Co, Al, Si, Ti, Ru, Mn, Mg, Cu, and Eu concentrations compared to the soil samples located away from thermal manifestations. This study demonstrates the potential use of LIBS coupled with PCA as a tool for variety discrimination of soil samples in a geothermal area. LIBS is shown to be a viable real-time elemental characterization technology for these samples, avoiding the rigorous dissolution required by other analytical techniques.

关键词： Cross-entropy loss   fine-grained vehicle classification   deep neural networks   ALGORITHM   SYSTEM  

摘要： Fine-grained vehicle classification is a challenging topic in computer vision due to the high intraclass variance and low interclass variance. Recently, considerable progress has been made in fine-grained vehicle classification due to the huge success of deep neural networks. Most studies of fine-grained vehicle classification based on neural networks, focus on the neural network structure to improve the classification performance. In contrast to existing works on fine-grained vehicle classification, we focus on the loss function of the neural network. We add a regularization term to the cross-entropy loss and propose a new loss function, Dual Cross-Entropy Loss. The regularization term places a constraint on the probability that a data point is assigned to a class other than its ground-truth class, which can alleviate the vanishing of the gradient when the value of the cross-entropy loss is close to zero. To demonstrate the effectiveness of our loss function, we perform two sets of experiments. The first set is conducted on a small-sample fine-grained vehicle classification dataset, the Stanford Cars-196 dataset. The second set is conducted on two small-sample datasets, the LabelMe dataset and the UIUC-Sports dataset, as well as on one large-sample dataset, the CIFAR-10 dataset. The experimental results show that the proposed loss function improves the fine-grained vehicle classification performance and has good performance on three other general image classification tasks.

关键词： 血清C肽   糖化血红蛋白   联合检验   糖尿病   诊断   作用  

摘要： 目的对血清C肽与糖化血红蛋白联合检验在糖尿病诊断中的作用进行探究和分析。方法选取了2015年8月—2017年8月在该院进行了糖尿病诊断的82例患者为主要对象,采用双盲法将患者分成了对照组(n=41)和观察组(n=41)两个组别。对照组选择的均为健康体检患者,观察组则为已经确诊了的糖尿病患者,对所有患者均采取血清C肽与糖化血红蛋白的联合治疗,之后对比两组之间的最终检测结果。结果对照组中患者的2 h血糖以及空腹血糖C肽均显著低于观察组,差异有统计学意义(P<0.05);对照组中患者的糖化血红蛋白、空腹血清C肽以及进餐2h后的血清C肽明显低于观察组,差异有统计学意义(P<0.05)。结论健康状态体检者的糖化血红蛋白以及血清C肽和糖尿病患者具有非常大的差异,因此血清C肽与糖化血红蛋白联合检验可以运用于糖尿病患者当中,并且具有较高的诊断价值,值得在临床进行推广。

关键词： 呼吸系统   感染   细菌   病毒   血清降钙素原  

摘要： 目的研究呼吸系统感染患者在治疗期间对血清降钙素原水平进行检测的临床价值.方法选择过去在我院治疗的呼吸系统细菌感染和病毒感染的确诊患者各53例,再抽取同期接受健康体检的53例同年龄段健康人资料,分别将其定义为研究1组、研究2组、对照组.对三组研究对象的血清降钙素原水平采用化学发光免疫分析法进行测定,对比检测结果和检测结果阳性率情况.结果研究1组研究对象血清降钙素原水平高于研究2组和对照组,有统计学意义(P<0.05);研究2组研究对象血清降钙素原水平高于对照组,有统计学意义(P<0.05).研究1组血清降钙素原阳性例数多于研究2组和对照组,有统计学意义(P<0.05);研究2组血清降钙素原阳性例数多于对照组,有统计学意义(P<0.05).结论呼吸系统细菌感染患者的血清降钙素原水平会明显高于病毒感染患者和健康人群,临床上可以将这一特点作为,病情筛查和治疗效果评价的参考指标.

关键词： 纺锤体检查点   减数分裂   有丝分裂   纺锤体组装   细胞分裂  

摘要： 染色体精确分离是在纺锤体的正确组装和纺锤体检查点(spindle assembly checkpoint,SAC)的监控下完成的,对于哺乳动物卵母细胞来说,纺锤体的形成和SAC都是保证染色体精确分离的重要因素,如果染色体分离错误将直接导致自发性流产或其他出生缺陷。卵母细胞中心体缺失后,细胞依然能够依靠独立于中心体而围绕染色体成核的微管反向平行排列能形成双极纺锤体,即自我组装纺锤体。由微观组织中心(microtubue organizing center,MTOC)召集微管聚集,成熟促进因子(maturation promoting factor,MPF)维持两次减数分裂过程中纺锤体的形成过程,细胞静止因子(cytostatic factor,CSF)维持分裂中期结构,使纺锤体在染色体没有全部集合到赤道板时保持稳定。大体积的卵母细胞容易产生非整倍体,且卵母细胞中不含有中心体这一特殊性导致卵母细胞中是否存在SAC在很长一段时间内存在争议,但现在SAC是确保卵母细胞染色体精确分离的机制之一已被初步证明。在减数分裂中期染色体之间存在一种黏连,细胞会产生"等待-后期"信号抑制SAC活性,从而保持这种黏连稳定,直至所有染色体完成与纺锤体的连接,"等待-后期"信号失活,SAC启动,使染色体间的黏连失活,进而在纺锤体的作用下染色体分离。作者综述了减数分裂过程中纺锤体的特异性组装过程和纺锤体检查点的组成及作用机制,丰富了减数分裂的相关知识,并为减数分裂过程中非整倍体的形成机制提供依据。

关键词： PPP   财政预算约束   实证检验  

摘要： PPP被广泛应用于基础设施建设,并且在现实生活中被寄予为缓解财政预算约束的工具。本文将财政预算分为短期预算与长期实力指标,并且通过对PPI数据库135个中、低收入国家1990-2016年数据的实证分析,发现广大发展中国家PPP模式参与基础设施建设的决策与长期以税收为代表的税收能力呈负相关。说明PPP模式应该作为公私合作提供公共物品的一种实现方式,而不宜将其作为解决财政负担的模式,PPP投资应与以税收为代表的财政实力相匹配。建议"一带一路"沿线国家和地区应提升其经济实力、改善投资环境等;国内省市区则要防止PPP成为地方债的变型;企业参与PPP建设则要发挥技术、信息等轻资产优势,注重国家投资分析和风险防范。