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51.
Donald G. York 《Zygon》1995,30(3):477-478
Abstract. Frank Tipler's The Physics of Immortality provides abundant cause for intellectual offense—including challenges to physics, to theology, and, seemingly, to common sense. Few philosophical conundrums remain unaddressed. Still, the book is stimulating and well presented. 相似文献
52.
This article explores how the sales budget is set in a business organization. Findings from a longitudinal participant observation study revealed that the sales budget is considered of great importance to the organization as sales estimates serve as premises for planning of production and supply and new product developments. It was observed that the sales budget was based on a narrow, inner-directed perspective, almost looking away from important environmental driving forces such as competitors and customers. The findings also showed that individuals involved in the sales budgeting process behaved opportunistically, influencing the budgetary process and outcomes. Theoretical and normative implications are highlighted. 相似文献
53.
Eavesdropping can be defined as the extraction of information from the interactions between other individuals. It provides
a relatively cheap way of gathering relevant information for fitness enhancement. Here, we propose that obligate avian brood
parasites, which always lay their eggs in foreign nests of individuals of other species, may eavesdrop on their host sexual
signals to locate nests of high quality individuals in which to lay their parasitic eggs. Sexual signal variation can honestly
signal parental quality. Thus, by eavesdropping on sexual signals, parasites may select high quality foster parents for their
own offspring. Such a use of sexual signals within host populations by brood parasites differs from signal exploitation theory
that proposes that parasite only use signals to locate potential host independently from signaller quality. Here, we review
the avian literature concerning host choice within a host species by obligate avian brood parasites and find evidence for
host selection within individuals of a host species on the basis of cues potentially functioning as sexually selected traits,
or at least revealing parental abilities. We have also found support for the existence of benefits linked to host selection
by avian brood parasites. Finally, one study reported on the attenuation of a sexual ornament in host populations under strong
pressure by brood parasites. Most of these findings have been interpreted as evidence for host selection by avian brood parasites
based on the conspicuousness of sexual signals. We suggest, however, that these findings may in fact reveal eavesdropping
on host signalling performance by brood parasites which would use the information extracted to choose the better individuals
among conspecifics of a given host. This provides a new perspective for the study of host selection in obligate brood parasites,
and raises interesting questions for the study of animal cognition that would deserve experimental studies. 相似文献
54.
Terrence W. Deacon 《Zygon》1996,31(4):635-670
Abstract. Language and information processes are critical issues in scientific controversies regarding the qualities that epitomize humanness. Whereas some theorists claim human mental uniqueness with regard to language, others point to successes in teaching language skills to other animals. However, although these animals may learn names for things, they show little ability to utilize a complex framework of symbolic reference. In such a framework, words or other symbols refer not only to objects and concepts but also to sequential and hierarchical relationships with other symbols. This process is essential to human mental operations, including language, mathematics, and music. In humans, these operations may have coevolved with the prefrontal area of the cerebral cortex, which is proportionately much larger in humans than in other animals and more intricately linked with other areas of the brain. Analysis of the structure and function of the prefrontal area suggests that it is centrally involved in the operation of higher-order associative relationships involving the subordination of one set of associations to another. This alternate learning strategy apparently appeared at the cost of certain sensory, motor, or limbic abilities. The payoff was symbolic thinking. Humans thus are unique among species, not just for their highly developed language ability but for their odd style of thinking and learning. 相似文献
55.
A Ohta 《Journal of the experimental analysis of behavior》1987,48(3):355-366
In a conditional discrimination procedure, pigeons' observing responses were analyzed to examine whether two color stimuli (blue or red), conditionally related to whether each of two line stimuli (vertical or horizontal) accompanied reinforcement or nonreinforcement, functioned as conditioned reinforcers. If a variable-interval (VI) 10-s requirement was fulfilled, an observing response produced onset of a color stimulus. A little later, a line stimulus was presented independently of responding, added to the color stimulus to form a compound stimulus. If 55 s elapsed with a response not having occurred either through 55 s or after the variable-interval 10-s had timed out, one of the color-line compound stimuli was presented independently of responding. To control for sensory reinforcement effects and for earlier entrance to the later link, a simple discrimination procedure also was conducted in which reinforcement was not correlated with the color stimuli but with the line stimuli only. As in the conditional discrimination, the observing response also could produce earlier presentation of blue or red. The observing response occurred more frequently during the conditional discrimination than during the simple discrimination. The results were related to different theoretical accounts of conditioned reinforcement, particularly the information hypothesis. 相似文献
56.
57.
两个实验以合理型主题信息条件下的句子为对照材料.其它型主题信息条件下的句子为实验材料,考察合理型和非合理型主题信息条件下汉语歧义句意义建构的时间进程和特点。结果表明:(1)合理型主题信息可以顺利地建构一个稳定的基础心理表征;不合理型主题信息则没有这种效应;矛盾型主题信息则引导读者重构一个新的心理表征。(2)在合理型主题信息条件下,语境主要起到证实主题信息区和歧义区所建构的基础表征的作用;而在不合理型、矛盾型主题信息的条件下,语境的作用首先是验证所建构的基础心理表征和歧义句的意义频率,然后有效建构歧义句的意义。 相似文献
58.
59.
Gardenier JS 《Science and engineering ethics》2003,9(3):425-434
This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September
5–6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation
are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists
and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions
agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed
about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue
restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author’s
notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately
reflect the primary intent of their presentations. The “Suggested Readings” offered at the end are not specific to the speakers’
statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is
planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003.
John Gardenier is an independent researcher, ethicist and science writer. 相似文献
60.
Lateralization of egocentric and allocentric spatial processing after parietal brain lesions 总被引:1,自引:0,他引:1
Tina Iachini Gennaro Ruggiero Massimiliano Conson Luigi Trojano 《Brain and cognition》2009,69(3):514-520
The purpose of this paper was to verify whether left and right parietal brain lesions may selectively impair egocentric and allocentric processing of spatial information in near/far spaces. Two Right-Brain-Damaged (RBD), 2 Left-Brain-Damaged (LBD) patients (not affected by neglect or language disturbances) and eight normal controls were submitted to the Ego-Allo Task requiring distance judgments computed according to egocentric or allocentric frames of reference in near/far spaces. Subjects also completed a general neuropsychological assessment and the following visuospatial tasks: reproduction of the Rey-Osterreith figure, line length judgement, point position identification, mental rotation, mental construction, line length memory, line length inference, Corsi block-tapping task. LBD patients presented difficulties in both egocentric and allocentric processing, whereas RBD patients dropped in egocentric but not in allocentric judgements, and in near but not far space. Further, RBD patients dropped in perceptually comparing linear distances, whereas LBD patients failed in memory for distances. The overall pattern of results suggests that the right hemisphere is specialized in processing metric information according to egocentric frames of reference. The data are interpreted according to a theoretical model that highlights the close link between egocentric processing and perceptual control of action. 相似文献