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71.
Summary The geometric isomers (E,E)-, (E,Z)-, (Z,E)-, and (Z,Z)-8,10-dodecadien-1-yl acetate were identified as sex pheromone components or sex attractants in the tribes Eucosmini and Grapholitini of the tortricid subfamily Olethreutinae. Species belonging to the more ancestral Tortricinae were not attracted. Each one isomer was behaviourally active in males ofCydia andGrapholita (Grapholitini), either as main pheromone compound, attraction synergist or attraction inhibitor. Their reciprocal attractive/antagonistic activity in a number of species enables specific communication with these four compounds.Pammene, as well as otherGrapholita andCydia responded to the monoenic 8- or 10-dodecen-1-yl acetates. Of the tribes Olethreutini and Eucosmini,Hedya, Epiblema, Eucosma, andNotocelia trimaculana were also attracted to 8,10-dodecadien-1-yl acetates, but several otherNotocelia to 10,12-tetradecadien-1-yl acetates. The female sex pheromones ofC. fagiglandana, C. pyrivora, C. splendana, Epiblema foenella andNotocelia roborana were identified. (E,E)- and (E,Z)-8,10-dodecadien-1-yl acetate are producedvia a commonE9 desaturation pathway inC. splendana. CallingC. nigricana andC. fagiglandana females are attracted to wingfanning males.  相似文献   
72.
A honey bee (Apis mellifera) queen mates with about ten haploid drones, thus producing colonies composed of about ten subfamilies of super-sisters. An increasing but controversial body of literature supports the views that: (1) Members of each subfamily within a colony can recognise each other, and distinguish supersisters from half-sisters. (2) Members of each subfamily use this recognition information and increase the reproductive fitness of their own subfamily at the expense of half-sisters through behaviour termed nepotism. A mathematical model is developed that shows that task specialisation by subfamilies, and bees that repeatedly undertake the behaviour within subfamilies, can influence the numbers of interactions among super-sisters, relative to the numbers of interactions between half-sisters. The model is then evaluated using a data set pertaining to trophallaxis behaviour in a two-subfamily colony. It is concluded that with this data set, task specialisation and subfamily recognition were indeed confounded, suggesting that the apparent subfamily recognition could easily have been an artefact of task specialisation. Correspondence to: B.P. Oldroyd  相似文献   
73.
对一个磷肥厂周围12个村庄的人发、粮食和饮水硒、碘、氟进行了测定,利用改进的模糊数学中的群体识别法对以上数据进行分析,所得结果表明,受污染较重的几个村庄人体硒、碘、氟含量确实受到来自磷肥厂的大气高浓度硒、碘、氟的直接影响.  相似文献   
74.
评价指标的不确定性是影响巷道稳定性评价的关键。为提高巷道稳定性评价的针对性,建立科学合理的评价模型,从地质条件和工程实际出发,运用未确知测度理论,选取影响巷道稳定性的岩体结构、顶板岩性、岩层倾角、开采深度、施工质量、断面形状、断面面积、支护效果、顶板控制方法、顶板位移量、巷道使用时间等11项因素。根据实测数据建立各影响因素的未确知测度函数,构建矿山巷道的稳定性等级评价和排序模型。采用定性、定量方法分析巷道稳定性评价中的不确定性影响因素,利用熵计算各影响因素的指标权重。依照置信度识别准则进行等级判定,得出巷道稳定性评价结果,并进行稳定程度排序。将该方法应用于某矿8条回采巷道的稳定性评价中。岩层倾角、开采深度、顶板位移量等3个评价指标权重比值差异较大,属于敏感性评价指标。较巷道R_(03)而言,巷道R_(08)的岩层倾角和开采深度2个评价指标的敏感性尤为明显,比值分别达77.43%、-46.72%。置信度取值的增加对评价结果没有显著影响,评价结果的可靠度较高。研究表明,将未确知测度理论应用于巷道稳定性评价是可行的。  相似文献   
75.
王冠宁  邓亮 《火灾科学》2019,28(1):49-59
为实现火灾现场中多股铜导线熔痕的自动识别,采用主成分分析(PCA)和反向传播(BP)神经网络算法对四种多股铜导线熔痕(一次短路熔痕、二次短路熔痕、过负荷熔痕和火烧熔痕)的金相组织进行了识别研究。利用Image-Pro Plus 6.0和Axio-Imaging软件获取每种熔痕30组17维金相组织参数数据,采用PCA对四种熔痕共120组数据降维,获得前6个主成分得分矩阵,建立具有6个输入层节点,10个隐层节点和4个输出节点的神经网络模式识别模型。随机抽取每种熔痕的20组样品的主成分得分矩阵作为训练集,将每种熔痕的剩余10组主成分得分为测试数据,输入最终训练完成的模型进行识别,其识别准确率达到92.5%。实验结果表明采用PCA+BP神经网络的算法,可以较好地实现多股铜导线熔痕识别,为火灾物证鉴定工作提供了有力的工具。  相似文献   
76.
The establishment of fighting rules and the ability to recognise individual conspecifics and to assess their fighting ability and/or roles may help to reduce costs of fighting. We staged encounters between males of the lizard Podarcis hispanica to examine whether lizards used fighting strategies and whether a previous agonistic experience affects the outcome and characteristics of a subsequent encounter. The results showed that simple rules such as body size differences and residence condition were used to determine the outcome of agonistic interactions as quickly as possible. Thus, larger males were dominant in most encounters. However, when size differences between opponents are smaller, they may be more difficult to estimate and, then, residence condition was more important. In addition, the intensity of interactions between males could be explained according to the ”sequential assessment game”, supporting the idea that P. hispanica males acquire information about fighting ability gradually during the progress of a fight. Our results also showed that the second fight of the same pair of males was less aggressive, even when its outcome was the opposite of the first. This result suggests that male P. hispanica can recognise individual opponents and that they use this information to reach a contest outcome more quickly, thus reducing unnecessary aggression levels in subsequent interactions. These fighting strategies and assessment mechanisms may help to stabilise the social system of this lizard. Received: 2 November 1999 / Revised: 26 August 2000 / Accepted: 4 September 2000  相似文献   
77.
Objective: The purpose of this study was to statistically determine which combination(s) of drug-related signs and symptoms from the Drug Evaluation and Classification (DEC) protocol best predict the drug category used by the suspected drug-impaired driver.

Methods: Data from 1,512 completed DEC evaluations of suspected impaired drivers subsequently found to have ingested central nervous system (CNS) depressants, CNS stimulants, narcotic analgesics, and cannabis were analyzed using a multinomial logistic regression procedure. A set of evaluations completed on drug-free subjects was also included. The relative importance of clinical, behavioral, and observational measures in predicting drug categories responsible for impairment was also examined.

Results: Thirteen drug-related indicators were found to significantly contribute to the prediction of drug category, including being under the care of a doctor or dentist, condition of the eyes, condition of the eyelids, mean pulse rate, assessment of horizontal gaze nystagmus (HGN), convergence, performance on the One Leg Stand (OLS) Test, eyelid tremors, pupil size in darkness, reaction to light, presence of visible injection sites, systolic blood pressure, and muscle tone. Indicators related to the appearance and physiological response of the eye contributed the most to the prediction of drug category, followed closely by clinical indicators and performance on the psychophysical tests.

Conclusions: The findings from this study suggest that drug recognition experts (DREs) should be careful to review a set of key signs and symptoms when determining the category of drug used by suspected drug-impaired drivers. Drug use indicators related to the appearance and physiological response of the eye were found to contribute the most to the prediction of the drug category responsible for the impairment. These results could help form the basis of a core set of indicators that DREs could initially consult to form their opinion of drug influence. This in turn may enhance the validity, effectiveness, and efficiency of drug detection and identification by DREs and lead to a more effective and efficient DEC program, improved enforcement of drug-impaired driving, and greater acceptance of the DEC program by the courts.  相似文献   

78.

This paper analyses the evolution of urban form in two North American metropolitan regions (Portland and Toronto) and asks how more sustainable regional form might come about in the future in these and other urban areas. In the past, dominant patterns of urban form have emerged in such regions at different historical periods. These morphological phases include mid 19th-century grids, streetcar suburb grids, garden suburbs, automobile suburbs and New Urbanist neighbourhoods (which have only recently made an appearance and may or may not become widespread). Judging by the performance of past types of urban morphology, five design values appear particularly important for more sustainable urban form in the future: compactness, contiguity, connectivity, diversity and ecological integration. Although these principles were not well supported by 20th-century development, contemporary movements such as the New Urbanism and Smart Growth re-emphasise them. The example of these two regions indicates that, in the absence of new technological, economic or geographical forces, public sector institutions and urban social movements represent the most likely means to bring about new, more sustainable types of urban form.  相似文献   
79.
以特殊互通式立交出口区域主线为研究对象,分析了特殊互通式立交出口交通事故特征,运用汽车制动特性、人机工程学及交通心理学原理获取驾驶员在特殊互通式立交出口处的识别视距,且识别视距均比设计规范值高.以特殊互通式立交出口识别视距为基础,运用几何学及高速公路几何线形原理建立识别视距与立交区域主线圆曲线半径关系模型,运用VB程序开发软件,提出特殊互通式立交出口处满足识别视距不同车道数主线圆曲线半径一般值和最小值.结果表明:对待建高速公路互通式立交出口位置所在主线线形应分析识别视距,并应利用识别视距对主线线形指标验算;对已建成特殊互通式立交出口,应加强其安全保障措施,保证主线及驶离主线车辆行车安全.  相似文献   
80.
This study integrates the emotion and social influence literatures to examine how emotion recognition ability (ERA) relates to annual income. In a sample of 142 employee–peer–supervisor triads from a broad range of jobs and organizations, we find that people's level of ERA indirectly relates to how much they earn per year. The relationship between ERA and annual income is mediated sequentially through political skill and interpersonal facilitation. The results imply that emotional abilities allow people not only to process affect‐laden information effectively but also to use this information to successfully navigate the social world of organizations in the pursuit of prosperity. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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