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191.
自从10年以前彼得·辛格的《动物解放》一书出版以来,在英国人的书籍中便对动物的道德处境的问题展开了激烈的讨论,在这期间,这个问题也在我们国家引起了较大的重视。从历史上看,这种关心无疑是对于自然的新意识的结果,而这种对于自然的新意识又是由于那些不能再忽视的生态问题产生的。可是按照事情的性质,我们这里所谈的与两个不同的问题有关。适当同自然环境打交道的问题是个我们共同的切身利益的问题,不是一种“生态  相似文献   
192.
The temporal characteristics of repetitive finger tapping by the left and right hands were examined in two experiments. In the first experiment, interresponse intervals (IRIs) were recorded while right-handed male subjects tapped in synchrony with an auditory timing pulse (the synchronization phase) and then attempted to maintain the same tapping rate without the timing pulses (the continuation phase). The left and right hands performed separately, at four different rates (interpulse intervals of 250, 500, 750, and 1500 ms). There was no asymmetry of the asynchronies of the timing pulses and the associated responses in the synchronization phase or of the IRIs in either phase, but there was an asymmetry of chronization phase or of the IRIs in either phase, but there was an asymmetry in the temporal dispersion of the responses in both phases. in the second experiment, right-handed males tapped separately with each hand at three different speeds: as quickly as possible, at a fast but steady rate, and at a slow rhythmical rate. The speed asymmetry present when tapping as quickly as possible (with the preferred hand tapping more quickly ) was reduced when tapping at the fast steady rate and was absent when tapping at the slow rhythmical rate. The temporal dispersion of the IRIs produced by the nonpreferred hand was greater than the temporal dispersion of those produced by the preferred hand in all speed conditions. These results show smaller temporal dispersion of tapping by the preferred hand in right-handed males under different conditions, including submaximal speeds at which both hands respond at the same rate. This suggests that the motor system controlling the preferred hand in right-handers had more precise timing of response output than that controlling the nonpreferred hand.  相似文献   
193.
This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs.  相似文献   
194.
Sexuality education for children and young adults is one of the most heavily debated issues facing policy-makers, national AIDS program planners, and educators, provoking arguments over how explicit education materials should be, how much of it there should be, how often it should be given, and at what age instruction should commence. In this context, the World Health Organization's Global Program on AIDS' Office of Intervention Development and Support commissioned a comprehensive literature review to assess the effects of HIV/AIDS and sexuality education upon young people's sexual behavior. 52 reports culled from a search of 12 literature databases were reviewed. The main purpose of the review is to inform policy-makers, program planners, and educators about the impact of HIV and/or sexuality education upon the sexual behavior of youth as described in the published literature. Of 47 studies which evaluated interventions, 25 reported that HIV/AIDS and sexuality education neither increased nor decreased sexual activity and attendant rates of pregnancy and sexually transmitted diseases (STDs). 17 reported that HIV and/or sexuality education delayed the onset of sexual activity, reduced the number of sex partners, or reduced unplanned pregnancy and STD rates Only 3 studies found increases in sexual behavior associated with sexuality education. Inadequacies in study design, analytic techniques, outcome indicators, and the reporting of statistics are discussed.  相似文献   
195.
A critical application of Ruddick's model of maternal thinking is the best way to grapple with the ethical dilemmas posed by sex-selective abortion which I view as a "moral mistake." Chief among these is the need to be sensitive to local cultural practices in countries where sex-selective abortion is prevalent, while simultaneously developing consistent international standards to deal with the dangers posed by the use of sex-selective abortion to eliminate female fetuses.  相似文献   
196.
2001年的科学哲学   总被引:1,自引:0,他引:1  
一种民主制度的最重要也是讨论最少的任务之一就是要保护它的成员免遭这种制度中的意识形态的伤害.必须正确地看待所有的意识形态.人们必须把它们当作神话故事来看待,它们能告诉人很多有趣的事,但也包含了很多谬误和令人生厌的谎言.当人们按照某一观点行动时,他们的态度也应该像密探一样,为了在一个陌生的国家里获得成功而采纳它的信仰并在细枝末节上按照这些信仰去做,但并不全盘接受.这一点适用于所有的信仰,适用于基督教上帝的存在这一信仰,适用于所有的人生来平等的信仰,也适用于科学.那么,这是否是一种陌生和荒谬的态度呢?科学当然总是处在与权威主义和迷信战斗的前沿.相对于宗教信仰而言,我们有了越来越大的思想自由,这应当归功于科学;人类从古代的僵硬思维方式中解放出来,也应当归功于科学.今天,这些思维方式仅仅是一些糟糕的  相似文献   
197.
Subjects (N = 8) performed a timed response task in which they attempted to synchronize an impulsive foot-press response with the last in a series of four regularly spaced tones. In Experiment 1, the response was countermanded on one third of the trials (stop trials) by a stop signal that appeared at a predetermined delay after the third tone. No stop signal appeared on the remaining trials (go trials). All subjects showed a systematic transition from withholding the response on stop trials in which the stop signal appeared shortly after the third tone to executing the response on trials in which a single stop signal delay had been chosen so that a response would be made on about 50% of the stop trials. We elicited Hoffmann (H) reflexes from the soleus muscle on all trials to determine whether the reflexes were augmented on occasions on which a response was prepared but withheld. Mean H-reflex amplitudes on go trials and on stop trials on which the response was executed were similar and showed a marked augmentation beginning about 250 ms before response onset; mean H-reflex amplitudes on stop trials on which the response was withheld showed less pronounced augmentation. Inspection of individual H-reflex amplitudes revealed that on stop trials on which the response was withheld the reflexes could be augmented to the same extent as on trials on which the response was executed. This dissociation of H-reflex augmentation and response execution shows that H-reflex augmentation reflects a controlled response process. Ballistic response processes therefore must be limited to a brief duration.  相似文献   
198.
Two experiments considered the behavior of subjects who cross gaps in a pathway without benefit of vision. The first experiment contrasted visually and nonvisually guided locomotion, finding a significantly greater number of refusals under nonvisual guidance but no loss of appropriate modulation of step components to the salient dimensions of the actor and layout. Different components of crossing were modified under guidance of different sensory systems; the lengths of the crossing and support spans were primarily altered under nonvisual guidance, and the distance of the support foot to the near edge of the gap was the component of preference under visual guidance. In the second experiment, subjects crossed nonvisually, using probes that varied in length and moment of inertia. The adaptability of the step components to actor and layout dimensions was unchanged, but there was no effect of these mechanical manipulations on the components of crossing identified in Experiment 1.  相似文献   
199.
现实论(actualism)这项方案,旨在清除逻辑与模态形而上学中那些讨人嫌的本体论承诺。它从一切存在的都是现实的这个观点出发,试图重新解释语言,以避免承诺“可能体”(possibilia)的存在。所谓“可能体”,指那些可能的,但非现实的对象。量化模态逻辑(QML)似乎就要求这种对象存在。最简QML为古典量化理论与模态命题逻辑之合并,可是它使巴康(Barcan)公式(今日x由→ax令Q)有效。从而,由可能存在一头会说话的驴子这个事实,就推出了存在某物,它可能是一头会说话的驴子。这看起来在宣称一个可能实体的存在(假定每个现实的东西都不可能是会说话的驴子)。现实论者们大力主张克里普克(Kripke)所描述的语义学,以此来免除这项承诺,这种语义学采用了可变论域,因而使巴康公式归于无效。  相似文献   
200.
推断论伦理学家就堕胎和安乐死的问题而提出的命题,主要是澳大利亚人P.辛格的那些命题,一直引起激烈的论战。推断论将生命保护理解为一种利益保护,它使个体的生命权利依赖于成为人的那种特性。按照推断论的观点,不是所有人类的个体都是人,因而就不能赋予非—个人的人类个体以生命权利——这在实践中是有相应的结果的。不管对P.辛格的命题在感情上的反应多么可以理解,光靠这些命题是得不到什么结果的,因为重要的是研究这些命题所引用的证据,研究那些已经决定了推断论的问题表述的前概念。只要推断论的潜在的前题不受到怀疑,人们也许将无法摆脱单纯的口头侮辱。  相似文献   
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