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41.
本文旨在证明,先验指号学可以理解为第一哲学的一种新范式,就是说,可以理解为语言分析范式的完成。语言分析范式作为第一哲学的第三种范式是继承前两种范式的,即亚里士多德意义上的本体论或形而上学,以及康德意义上(或从笛卡儿到胡塞尔的近代哲学的更广泛意义上)的关于意识的先验哲学。在我看来,新的范式可以“扬弃”(在黑格尔意义上)以前的两种范式。  相似文献   
42.
This article describes developmental changes in gait velocity and relates these changes to gait parameters that index postural stability (step width and lateral acceleration) and two components of velocity (cadence and step length). Five children were observed longitudinally over a 2-year period after onset of independent walking. Their range of speed increased threefold in the first 6 months of independent walking and then remained constant. In contrast, step width decreased approximately twofold. Whereas in adults, cadence and step length contribute approximately equally to speed, when infants first begin to walk independently, increase in velocity is due mostly to increased step length. After 5 months of independent walking, the pattern reverses, and increase in velocity is due primarily to increased cadence. The pattern remains constant over the next 18 months. From a developmental point of view, the data lead us to interpret early walking (the first 5 months) as a process of integration of postural constraints into the dynamic necessities of gait movement. A second phase, beginning after 4 to 5 months of independent walking, is considered to be a tuning phase characterized by a more precise adjustment of the gait parameters.  相似文献   
43.
While looking through laterally displacing prisms, subjects pointed 60 times straight ahead of their nose at a rate of one complete movement every 2 or 3 s, with visual feedback available early in the pointing movement or delayed until the end of the movement. Sagittal pointing was paced such that movement speed covaried with pointing rate. Aftereffect measures (obtained after every 10 pointing trials) showed that when the limb became visible early in a pointing movement, proprioceptive adaptation was greater than visual, but when visual feedback was delayed until the end of the movement, the reverse was true. This effect occurred only with the 3-s pointing rate, however. With the 2-s pointing rate, adaptation was predominately proprioceptive in nature, regardless of feedback availability. Independent of the availability of visual feedback, visual adaptation developed more quickly with 3-s pointing, whereas proprioceptive adaptation developed more rapidly with 2-s pointing. These results are discussed in terms of a model of perceptual-motor organization in which the direction of coordinative (guidance) linkage between eye-head (visual) and hand-head (proprioceptive) systems (and consequently the locus of discordance registration and adaptive recalibration) is determined jointly by pointing rate and feedback availability. An additional effect of pointing rate is to determine the rate of discordant inputs. Maximal adaptive recalibration occurs when the input (pointing) rate matches the time constant of the adaptive encoder in the guided system.  相似文献   
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Six pigeons were trained to discriminate between two intensities of white light in a symbolic matching-to-sample procedure. These stimuli were then used to signal which schedule was available on the main key in a switching-key concurrent schedule. The concurrent schedules led to a symbolic matching-to-sample phase in which the subject identified the concurrent schedule to which it last responded before a reinforcer could be obtained. The concurrent schedules were varied across conditions. Discriminability, measured during the symbolic matching-to-sample performance, was high throughout and did not differ across the two procedures. Performance in the concurrent schedules was like that typically obtained using these schedules. Delays were then arranged between completion of the concurrent schedules and presentations of the symbolic matching-to-sample phase. A series of conditions with an intervening delay of 10 s showed that both concurrent-schedule performance and symbolic matching-to-sample performance were affected by the delay in a similar way; that is, choice responding was closer to indifference.  相似文献   
46.
Three rats earned their daily food ration by responding during individual trials either on a lever that delivered one food pellet immediately or on a second lever that delivered three pellets after a delay that was continuously adjusted to ensure substantial responding to both alternatives. Choice of the delayed reinforcer increased when the number of trials per session was reduced. This result suggests that models seeking closure on choice effects must include a parameter reflecting how preference changes with sessionwide income. Moreover, models positing that reinforcer probability and immediacy (1/delay) function equivalently in choice are called into question by the finding that probability and immediacy produce opposing effects when income level is changed.  相似文献   
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48.
Hispanic Americans have one of the highest rates of HIV seroprevalence among all ethnics groups in the US, with high rates being especially noticeable among women and children. Were it known which cultural factors have the most influence on whether Hispanics engage in high-risk behavior for HIV transmission, prevention interventions could be targeted accordingly. To that end, this study was mounted to identify which Hispanic cultural factors relate to condom use. 117 males and 73 females aged 17-56 years of mean age 25.67 were surveyed in Washoe county, Nevada. These mostly young adults had recently immigrated to the western US. It was initially posited that fate orientation, male- female relationships, family relationships, machismo behavior, and religion would have equal influence with respect to condom use. Analysis found that condom use was largely associated with and determined by men who are the principal buyers of condoms. A machismo attitude toward protecting women by using condoms was also associated with condom use. Neither fate orientation with respect to AIDS, nor religion were important determinants of condom use, even though 86.5% of the respondents were Catholic. The degree to which respondents adhered to traditional Hispanic cultural values was influenced by the degree of education and acculturation. On the basis of these findings, the authors suggest targeting AIDS prevention messages to males, while emphasizing the protection of women through condom use. They also suggest that both education and acculturation levels be assessed before implementing prevention programs.  相似文献   
49.
The legal consensus that has evolved through adjudication and legislation since the Karen Quinlan case in 1976 is founded on the premise that there is a bright line between passive euthanasia and active euthanasia. Indeed, the term passive euthanasia is often eschewed in favor of less emotionally-laden terminology such as "forgoing life-sustaining treatment" or "terminating life support" so as to further sever any possible connection with active euthanasia. Legal approval has been bestowed upon passive euthanasia under certain circumstances while active euthanasia is routinely condemned. This consensus was put to a test in 1990 when the United States Supreme Court ruled on the Cruzan case. However, the Court's narrow decision did not upset the consensus, and in the most significant appellate decisions handed down by state courts since Cruzan, there has been a reaffirmation--and possibly even an extension--of the consensus. Two other threats to the legal consensus about forgoing life-sustaining treatment have begun to manifest themselves: the increasing pressure for mercy killing and "futility" cases. Both of these challenge the fundamental premises on which the consensus is grounded.  相似文献   
50.
第9届维特根斯坦国际专题讨论会的主题是心灵哲学(philosophy of mind,或译心智哲学)和心理学哲学。详细地讨论过的问题包括:心身问题、心灵哲学的传统问题和心理学哲学。 1.心身问题什么是心身问题?“心灵”(mind)一词有多种非常不同的用法,这一事实导致了现代讨论中的某种混乱。对这个词,我们至少可以区分出五种不同的用法,因此心身问题至少有五种意义。 (1)我们可以象笛卡儿使用“mens”一词那样使用“心灵”一词,让它指称具有心理属性的东西,亦即指称那种能思想,能感知,能相信和能欲求的东西。在这种情况下,我们通常是用“心灵”这个词意指“人”这个词所意指的东西,因而该词表示的就是你和我这样一些实  相似文献   
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