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51.
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.  相似文献   
52.
A review of the literature and ethnographic data from Australia, Canada, New Zealand, the United States, and the United Kingdom on the research ethics review process suggest that moral panics can become triggers for punctuated equilibrium in the review process at both the macro and microlevel, albeit with significantly different levels of magnitude and impact. These data suggest that neither the development of the ethics review process nor the process itself proceeds gradually, but both are characterized by periodic major shifts evoked by particular events or situations that result in varying levels of moral panic. One way to deal with this moral panic is to increase the regulation of research and the depth or intensity of the scrutiny of applications under ethics review. Moral panics at the macrolevel influence those at the microlevel and, if the moral panic evoked at the local or microlevel is not satisfactorily resolved, it will evoke action at a higher level. Understanding the evolution of research ethics review processes from this perspective might help make actions by ethics committees and policy makers more understandable and help explain why attention to research ethics are heightened at particular points in time. It may also provide a basis for developing recommendations for adaptations to the ethics review process and policy at both the local and macrolevel.  相似文献   
53.
人口逆淘汰及其预防   总被引:2,自引:0,他引:2  
对人口逆淘汰必须全面、动态地加以认识.必须阻止人口逆淘汰,提高人口质量,变"人口"为"人力".教育是关键措施,医疗卫生和环境改善十分重要,但决不能鼓励高学历人口多生育而限制农村人口的出生.  相似文献   
54.
Cerebellar volumes show small positive correlations with cognitive ability in young adults, but no studies have examined this relationship in older adults. Furthermore, no studies have examined relationships between sizes of subareas of the cerebellum and cognitive ability. We hypothesized that size of the two areas of the neocerebellar vermis would correlate with a battery of eight cognitive tests in 50 men aged 65-70. Size of the neocerebellar areas of the vermis correlated positively with several cognitive tests (r's=.29-.37, p<.05), whilst sizes of other parts of the vermis did not correlate with any cognitive tests. Total cerebellar volumes correlated significantly with a test of nonverbal reasoning (r=.030, p=.42). These findings suggest a specific association of neocerebellar vermis size with variations in cognitive ability in older adults.  相似文献   
55.
Although reactivation and reinstatement reminders differ procedurally, differences in their memory-preserving effects have been described as artifactual. In three experiments, we examined this conclusion. One hundred and twelve 6-month-olds learned an operant task, forgot it, received a reactivation or reinstatement reminder to recover the inactive memory, and were tested after increasing delays until they forgot it again. In Experiments 1a and 1b, a single reactivation reminder extended infants' memory of an operant mobile task for 2 weeks after reminding, but a single reinstatement extended it for 4 weeks, when testing was discontinued. In Experiment 2, a single reinstatement extended 6-month-olds' memory of an operant train task for 19 weeks after reminding, when infants were almost 1 year old. After reactivation, infants remember this task for only 2 weeks. The finding that the memory-preserving effect of reinstatement is greater by an order of magnitude suggests that procedural differences between the two reminders have functional significance.  相似文献   
56.
B. F. Skinner's Science and Human Behavior (1953) became the main source of my understanding of behavior during my first semester as a college professor in 1955 at Kansas University. It has continued to exert a major influence throughout my career as the basis for a completely deterministic science of behavior, as a handbook to be consulted as a first step in dealing with any issue in behavior analysis, and as a tutorial in behavioral interpretive analysis--in the use of a small number of behavioral concepts and principles to understand behavior of all degrees of complexity. I describe four general interpretive orientations or maxims that are of broad significance for behavior analysis, and also two underappreciated major theoretical contributions.  相似文献   
57.
《孔丛子》六卷当出自“汉魏孔氏家学” ,其前三卷记孔子、子思言行 ,可能是辑先秦孔氏遗文。《孔丛子·记义》篇载有一大段孔子对《诗》的评论 ,其与上博简《孔子诗论》有着内在的关系 ,可以将它们视为同一个体系而相互参释和补充。《孔丛子》“诗论”与上博简《诗论》都反映了先秦儒家早期说诗的风格和内容 ,而与汉代形成的《诗序》传统不同。《孔丛子》“诗论”对朱熹的《诗经集传》有一定影响 ,在从汉代诗学向宋代诗学的转变过程中起了一定的作用。  相似文献   
58.
The papers in this special issue of Clinical Child and Family Psychology Review provided an overview of what is known about children's exposure to domestic violence, and include indications of gaps in extant research. These gaps and research needs are summarized in this conclusion. Specifically, there is need for further research in several broad areas: definition and measurement of children's exposure to domestic violence; development of research methods and statistical designs that provide detailed information and provide for evidence of intervention effectiveness; impact of domestic violence on parenting and family functioning; the role of child factors and exposure to violence factors in predicting developmental risk and resilience; medical and health consequences of exposure to violence; and the nature of child-system interaction in response to domestic violence. Research needs in these areas are discussed in greater detail, and specific questions are raised for further development.  相似文献   
59.
This paper forms an introduction to this issue, the contents of which arose directly or indirectly from a conference in May 2001 on Corruption of scientific integrity? — The commercialisation of academic science. The introduction, in recent decades, of business culture and values into universities and research institutions is incompatible with the openness which scientific and all academic pursuit traditionally require. It has given rise to a web of problems over intellectual property and conflict of interest which has even led to corporate sponsors’ suppressing unfavourable results of clinical trials, to the detriment of patients’ health. Although there are those who see the norms of science developing to recognise the importance of instrumental science aiming at specific goals and of knowledge judged by its value in a context of application, none justifies the covert manipulation of results by vested interest.Public awareness of these problems is growing and creating a climate of opinion where they may be addressed. We suggest a way forward by the introduction of nationally and internationally-accepted guidelines for industrial collaboration which contain proper protections of the core purposes of universities and of the independence of their research. Some codes suggested for this purpose are discussed. We note that some universities are moving to adopt such codes of conduct, but argue the need for strong support from the government through its funding bodies.  相似文献   
60.
Three frames of reference for engineering ethics are discussed—individual, professional and social—which can be further broken down into “microethics” concerned with individuals and the internal relations of the engineering profession and “macroethics” referring to the collective social responsibility of the engineering profession and to societal decisions about technology. Few attempts have been made at integrating microethical and macroethical approaches to engineering ethics. The approach suggested here is to focus on the role of professional engineering societies in linking individual and professional ethics and in linking professional and social ethics. A research program is outlined using ethics support as an example of the former, and the issuance of position statements on product liability as an example of the latter. An earlier version of this paper was presented at the International Symposium on Technology and Society 2000 (ISTAS 2000), Rome, Italy, 7 September 2000. Joseph R. Herkert directs a dual-degree program in engineering and humanities/social sciences and is editor of Social, Ethical, and Policy Implications of Engineering (Wiley/IEEE Press).  相似文献   
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