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101.
This study evaluated the effects of time of day, ambient temperature, and relative humidity on mother-infant interactions in captive Japanese macaques (Macaca fuscata). Unlike time of day and relative humidity, temperature influenced mother-infant interactions. Even though total time spent in ventroventral contact did not change, lower temperatures were associated with greater attempts by the infants to maintain contact with their mothers and with more frequent maternal rejection. Effects of temperature on mother-infant interactions were not mediated by the effects of temperature on mothers' general activity. These results are interpreted in light of the different thermoregulatory needs of mothers and infants, and highlight a previously neglected cause for mother-infant conflict. Received: 23 June 1997 / Accepted after revision: 28 March 1998  相似文献   
102.
Unsafe behavior is one of the main causes limiting the improvement of on-site safety performance. Safety training is an important means of preventing unsafe behavior. With changes in the scale of operations and employee characteristics, traditional training methods have largely failed to meet the practical demands. Therefore, to improve the effectiveness of safety training, this paper analyzes the shortcomings of the current training methods, demonstrates the potential value of accident cases for improving the training effect, and the advantages of 24Model for case analysis in safety training. Subsequently, this paper constructs a systematic training system with Accident-Cause-Training (ACT) as the training relationship chain, which runs the accident cases throughout the training process, 24Model is utilized to trace the unsafe behaviors that lead to accidents from the perspectives of organizational and individual level, and the training content is established according to the analysis results. This paper also conducts a case study to verify the operability of the ACT method, specifically, a training programme for limited space operations at a national-level oil and gas storage and transportation company is designed and implemented. Finally, by comparing the similarities and differences between the ACT method and other training methods from various perspectives, the universality and participation of the ACT method are proved, and the development trend of the ACT method is also discussed. It is believed that the proposed ACT method could enrich the types of safety training methods and provide an effective and scientific tool to enhance the safety performance of field operations.  相似文献   
103.
Gains in reducing mortality and morbidity from motor vehicle crashes can be achieved by understanding the behavioral factors that contribute to the elevated risk of motor vehicle-related injury and death. This study investigates the incidence, along with the effect of driver and behavioral factors, on the likelihood of motor vehicle crashes. Seventeen year old newly licensed drivers (n = 1277) in Perth, Western Australia, were recruited and followed over the first 12 months of driving. Using Cox proportional hazard analysis, driver and behavioral factors were assessed to determine whether they predicted the likelihood of a crash in the first 12 months of driving. The crash incidence rate was higher for males (1R = 4.6/10,000 driving days) than females (IR = 3.9/10,000 driving days). Multivariate analysis indicated that drivers who reported to have driven daily prior to obtaining their learners permit (L-plates) were at an increased risk of motor vehicle crash. A twofold increase in motor vehicle crash was apparent among drivers considered to be confident-adventurous drivers compared to low to moderate levels of driver confidence-adventurousness (HR = 2.04, 95% CI = 1.29-3.21). The research indicates that a driver's perception of their confidence and adventurousness in the road environment plays a part in the causal pathway leading to a motor vehicle crash. This research points to the need for preventive strategies that focus not only on knowledge and skill acquisition, but also the driver's perception in preparing young people for our roads.  相似文献   
104.
As most parasitoids are time limited, they usually die before they have laid all their eggs. In such cases, optimal foraging theory predicts that female parasitoids will adopt behavioral reproductive strategies enabling them to maximize progeny production per unit of time. One key situation in which parasitoid females must optimize their time budget is related to the fact that most of their hosts are distributed in discrete patches in the environment. In this review, I first present the results of basic theoretical models predicting female wasp search duration on a patch of hosts. I then compile and analyze all studies investigating the effect of different factors on parasitoid patch time allocation and patch-leaving decision rules. Different patch-leaving mechanisms that were proposed to explain the results obtained are discussed, along with statistical methods that should be used to estimate them from experimental data. Finally, ideas for future research are presented.  相似文献   
105.
Using four polymorphic microsatellite loci, we found that four Apis andreniformis queens collected in Thailand each mated at least 10–20 times, producing an average relatedness, g ww, of workers of 0.30 ± 0.007, and an average effective number of matings of 9.1 ± 2.2. The degrees of polyandry and intra-colonial genetic relatedness in A. andreniformis are similar to those in A. mellifera, slightly more than in A. florea, and up to 6 times less than in A. dorsata. We argue that while presently favoured hypotheses for the evolution of polyandry in monogynous social insects may adequately explain the evolution of up to five or six matings, they are inadequate to explain the extreme polyandry (10–60 matings) observed in Apis. One alternative possibility is that colony fitness is a non-additive function of the fitness of individual subfamilies. Such behavioral over-dominance may mean that queen fitness is increased by high levels of polyandry, which increase the probability of desirable combinations of worker genotypes occurring in one colony. The special attributes of honey bees which may lead to behavioral over-dominance include colony aggregation (which may increase the incidence of disease), and frequent long-distance migration. Received: 8 May 1996/Accepted after revision: 9 August 1996  相似文献   
106.
Pagurus longicarpus hermit crabs depend on empty gastropod shells for protection against predation. Hermit crabs avoid gastropod shells in which holes have been drilled by naticid gastropods, and hermit crabs forced to occupy drilled shells are more vulnerable to predation by green crabs, Carcinus maenas. In this study, we examined the effect of predator cues on P. longicarpus shell investigation behavior and shell choice. In paired laboratory shell choice trials, we examined hermit crab response to green crab chemical cues. We compared hermit crabs from two sites differing in the percentage of Littorina littorea shells with drill holes. The percentage of time hermit crabs spent occupying intact shells increased significantly in the presence of predator cues. The effect of predator cues on the amount of time hermit crabs spent investigating shells differed between individuals from the two sites. Predator effluent had a marginal effect on the proportion of hermit crabs initially choosing intact shells and within 15 min most hermit crabs in both treatments occupied intact shells due to shell switching. These results indicate that predation cues alter P. longicarpus shell choice behavior favoring intact shells, which provide greater protection. In summary, predation appears to be a key factor influencing hermit crab shell selection behavior.Communicated by T. Czeschlik  相似文献   
107.
The emergence of unshared consensus decisions in bottlenose dolphins   总被引:1,自引:1,他引:0  
Unshared consensus decision-making processes, in which one or a small number of individuals make the decision for the rest of a group, are rarely documented. However, this mechanism can be beneficial for all group members when one individual has greater knowledge about the benefits of the decision than other group members. Such decisions are reached during certain activity shifts within the population of bottlenose dolphins residing in Doubtful Sound, New Zealand. Behavioral signals are performed by one individual and seem to precipitate shifts in the behavior of the entire group: males perform side flops and initiate traveling bouts while females perform upside-down lobtails and terminate traveling bouts. However, these signals are not observed at all activity shifts. We find that, while side flops were performed by males that have greater knowledge than other male group members, this was not the case for females performing upside-down lobtails. The reason for this could have been that a generally high knowledge about the optimal timing of travel terminations rendered it less important which individual female made the decision. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and R. James).  相似文献   
108.
The social structure of animal aggregations may vary considerably in both space and time, yet little is known about how this affects vigilance. Here, we investigate the vigilance architecture of a colony of wild-living grey-headed flying-foxes (Pteropus poliocephalus) in Australia and examine how spatial as well as temporal variation in social organization influences social and environmental vigilance. We sampled color-marked individuals at different stages of the reproductive cycle and the year and at different locations in the colony to examine the effects of temporal and spatial factors on social and environmental vigilance. We found that vigilance architecture reflected the social structure of the colony, with the highest environmental vigilance being displayed by bats at the periphery of the colony, and the highest social vigilance by bats that roosted at intermediate distances from the colony’s edge. Furthermore, we found that vigilance levels reflected changes in reproductive state, with social vigilance increasing toward the mating season, particularly in males. Our findings show that spatial and temporal variation in social structure can have differential effects on social and environmental vigilance. This highlights the necessity to differentiate between functions of vigilance to understand fully vigilance architecture in aggregations of social animals.  相似文献   
109.
以中国为客源国,以日本为目的地国,通过问卷调查收集了477份有效问卷调查结果,并采用结构方程模型、中介效应分析了消费者敌意、消费者民族中心主义、国家形象对旅游意愿的影响。结果发现:(1)消费者敌意对国家形象有显著负向影响,对旅游意愿的影响不显著。(2)消费者民族中心主义对国家形象和旅游意愿有显著负向影响。(3)国家形象对中国消费者的赴日旅游意愿有显著正向影响。(4)消费者敌意与消费者民族中心主义呈正相关。(5)国家形象在消费者敌意、消费者民族中心主义与旅游意愿之间具有中介作用。  相似文献   
110.
文章基于文献分析,提出了消费价值差模型,并以此结合量表和结构方程模型来检验消费价值差对消费者绿色商品的消费意向与市场需求的影响。研究结果说明,消费价值差越大,绿色消费行为意向和市场需求程度越低,其中效用价值差与环境价值差的反向影响最大。鉴于上述结论,政府及企业在制定相关政策及设计推广绿色商品时,应重视消费者的认知和情感需求,并针对不同群体开展具有差异性的环保宣教工作。  相似文献   
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