Distorting Gene Pools by Conservation: Assessing the Case of Doomed Turtle Eggs

Sea turtles have a high reproductive output and high mortality at early stages of the life cycle. In particular, many nests are laid below or close to high tide lines, and subsequently large numbers of eggs may be inundated and destroyed. A common conservation procedure is to relocate such doomed eggs to higher ground. This article examines this practice in the light of recent data revealing that some individual turtles tend to nest relatively near the water and others relatively higher up the beach. Discussion is focused on the question of why apparently poor placement of nests has not been selected against. Comparison between the ecology of leatherback and hawksbill turtle nesting beaches suggests that predictability of environmental conditions on the nesting beaches has an important influence on patterns of nest-site selection. Options are outlined for the management of nesting beaches where a high proportion of turtle eggs is subject to destruction by flooding. An erratum to this article is available at.     

C/N对SBR生物脱氮硝化过程微生物结构的动态影响

为揭示碳氮比（C/N）对硝化过程影响的机理本质,试验以人工模拟废水为研究对象,采用4组平行的SBR（R₀、R₅、R₁₀、R₁₅）反应器,基于16S rRNA基因-Illumina MiSeq高通量测序技术,考察了4种C/N（0、5、10、15）对硝化过程功能微生物组成和结构特征的影响.结果表明：4种C/N条件下,系统均获得了较好的去除氨氮（去除率>95%）和COD（去除率>90%）效果,TN也有不同程度的降低.此外,C/N会显著影响系统内微生物的多样性、种群结构和功能.R₀系统Chao1指数（922）、ACE指数（1232.4）、Shannon指数（6.76）和Simpson指数（0.96）均最大,故微生物多样性最丰富,而R₅的物种丰富度最低.在微生物门水平上,变形菌门（Proteobacteria）、拟杆菌门（Bacteroidetes）、蓝细菌门（Cyanobacteria）等9个相对丰度较高的门是重要的微生物门,其中变形菌门（Proteobacteria）约全部微生物的40.7%~65.2%,是4个系统中最优势的菌门.硝化过程的关键菌群亚硝化单胞菌科（Nitrosomonadaceae）及硝化螺旋菌属（Nitrospira）的相对丰度表现出随着C/N升高而急剧降低的趋势.基于LEfSe分析共获得了34组具有显著差异的微生物,从而得到了每种C/N条件下在微生物学分类水平上的菌群关键生物标记物.     

产业结构视角下的新疆区域经济差异分解研究

区域经济差异与产业结构有着密切的联系.从三次产业结构的视角,运用加权变异系数对1995年以来新疆区域经济差异进行产业分解.研究发现,1995-2009年新疆第二、第三产业的加权变异系数明显高于人均GDP加权变异系数,对总体经济差异起着明显的"上拉"作用.通过三次产业对总体差异的贡献分析发现,第二产业差异对新疆总体经济差异的年均贡献率达73.5%,表明第二产业差异是造成新疆总体差异的关键因素,提出了缩小新疆区域经济差异的对策建议.     

企业员工个体安全行为的人类动力学实证研究

对员工不安全行为的定量分析是理解安全生产事故复杂系统的基础.班组或群体的集体行为往往表现为复杂有序,具有一定的稳定性和适应性;而个体行为尽管有企业制度和纪律的约束,却仍有很大的随机性.为了探究企业员工不安全行为的动力学规律,跟踪观察某大型企业作业员工930 d,将员工相继不安全行为的发生看作排队理论中具有特定时间序列的随机过程.结果表明,就员工个体而言,其不安全行为的间隔时间分布可以用幂律函数近似描述,且幂指数和员工的活跃程度正相关;并进一步分析出企业员工相继不安全行为具有以艾宾浩斯遗忘曲线为特点的“阵发”性;从幂指数角度分析了员工日常作业中的不安全行为的优劣特点,比较了人类活动中的各种随机行为与员工在企业生产中的不安全行为在时间统计上的特性.这表明企业制定安全管理制度及实施安全培训工作都应从人类普遍问题和员工个体特点两方面入手.     

“Winter” aggregations, colony cycle, and seasonal phenotypic change in the paper wasp Polistes versicolor in subtropical Brazil

Social wasps from temperate zones have clear annual colony cycles, and the young queens hibernate during winter. In the subtropics, the only previously reported evidence for the existence of “hibernation” is the facultative winter aggregations of females during harsh climate conditions. As in temperate-zone species analyzed so far, we show in this study that in the paper wasp, Polistes versicolor, a subtropical species, body size increases as an unfavorable season approaches. Our morphological studies indicate that larger females come from winter aggregations—that is, they are new queens. Multivariate analyses indicate that size is the only variable analyzed that shows a relationship to the differences. Given the absence of a harsh climate, we suggest that the occurrence of winter aggregations in tropical P. versicolor functions to allow some females to wait for better environmental conditions to start a new nest, rather than all being obliged to start a new nest as soon as they emerge.     

COVID-19 and individual performance in global virtual teams: The role of self-regulation and individual cultural value orientations

Since the onset of the COVID-19 pandemic, global virtual teams (GVTs) have become increasingly important. Drawing on conservation of resources theory and self-regulation theory, we examined the mechanism and process underlying individuals' performance in GVTs in this specific situation. We posit that the local severity of the pandemic has a negative effect on individuals' performance in GVTs and that self-regulation functions as a coping mechanism in times of pandemic-related ambient stress, reducing its negative effect on performance. We suggest that three cultural value orientations, that is, uncertainty avoidance, collectivism, and long-term orientation, explain different levels of self-regulation, which in turn moderates the relationship between the local severity of the pandemic and individual performance in GVTs. Based on a sample of 2727 individuals from 31 countries participating in an international business consulting project during the early stage of the unfolding pandemic, we show that (a) the local severity of the pandemic had a negative effect on individuals' performance, (b) the negative effect of the pandemic on performance is weaker for individuals with high self-regulation, and (c) uncertainty avoidance and long-term orientation are positively associated with self-regulation, which mediates the moderating relationship between the cultural value orientations and the relationship between the COVID-19 pandemic and individual performance in GVTs.     

森林采运作业个体伤害的工效学分析

森林采运作业是一种高危险作业,有效减少作业过程中的生产事故和作业人员个体伤害是企业安全管理工作的核心,本文运用系统工程学原理和人类工效学方法全面系统的分析了森林采运作业生产事故和作业人员个体伤害的致因,提出了减少采运作业生产事故和作业者个体伤害的对策。为采运企业安全生产管理提供了科学的决策依据。     

Size assessment via a visual signal in snapping shrimp

Snapping shrimp are highly aggressive decapod crustaceans, with large, asymmetric chelae. Body size determines the outcome of both inter- and intrasexual interactions. Both the body and chela sizes of mated pairs are correlated, but the body size correlation is significantly stronger. In competitive interactions between individuals of the same sex, larger individuals usually win. Because the size of the major chela is a function of body size in both males and females, chela size could be used to assess body size early in interactions, before engaging in more high risk behaviors. To determine whether the major chela is used in size assessment, I presented shrimp with isolated chelae. Male snapping shrimp responded aggressively to isolated chelae when they were fixed open in a display posture, and the degree of aggressive response depended on the relative size of the chela. These data provide direct experimental evidence for the use of a visual signal in size assessment. Females, in contrast, responded aggressively to both the open and closed chela, and their responses did not depend on relative size. This sex difference in response may be due to differences in the value of certain resources, such as shelters, to males and females: females may be more willing to respond aggressively regardless of the apparent size of their opponent, in order to acquire more reliable information regarding size, motivation or fighting ability. Received: 30 December 1994/Accepted after revision: 14 August 1995     

牛眼虹膜定位算法研究及其在肉食品追溯系统中的应用

为实现动物个体的精确鉴别,提高肉食品的安全性,将动物虹膜识别技术引入到肉食品供应链中,构建了基于虹膜识别的肉食品安全可追溯系统业务流程,实现了肉食品"从农场到餐桌"的安全保障;并以牛眼虹膜为例,根据其非同心椭圆的结构特征和图像仿射变换不变特征的原理,提出了一种牛眼虹膜快速定位方法。将牛眼虹膜内、外边界分别转化为圆形,对内边界采用灰度均值法粗定位与"三点定圆"精定位相结合的方法实现,对外边界设计了一种逐点扫描分层圆环算法来精确拟合。实验结果表明:该方法避免了虹膜信息丢失,减少了空间参数的选择运算。     

民航安全信息个体自愿报告意愿的影响因素研究

在前人研究成果的基础上,选择认知水平、同事顾虑、上级领导抵触、利己考虑、集体考虑、系统本身、安全文化7个影响因素,并依据SCASS分类标准,将上报意愿分为6个维度(报告提交经验、航空器不良运行或设备缺陷报告提交意愿、自身违规差错报告提交意愿、空防安全事件或隐患报告提交意愿、执行标准或飞行程序困难事件报告提交意愿、同事发生此类事件报告提交意愿),构建并验证个体自愿上报意愿的影响因素模型。研究发现,各类事件上报意愿分别受到不同的因素影响,其中,认知水平和安全文化对上报意愿起到正向影响,其他影响因素起到负向影响。本研究为民航单位针对性提高员工上报意愿提供理论指导。