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81.
A computer-controlled language training system was designed and constructed to enhance the objectivity and efficiency of inquiry into the language-relevant behaviors of apes. The system allows the S to gain control over the events of the 24-h day in direct correspondence with its competence in using a keyboard on which each key represents a word. Various incentives can be obtained through the selection and depression of appropriate keys in accordance with rules of sentence structure monitored by a computer. The system is flexible and allows for eventual conversation between man and ape, with the computer as the intermediary. A Teletype records all that transpires. Achievements of the chimpanzee S over the course of the first 8 months of the system’s operation attest to the worth of the system and training methods.  相似文献   
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According to a recent hypothesis, the prefrontal cortex has been proposed as the site of emotional memory integration, because it is sensitive to the recognition of emotional contents. In the present research, we explored the role of the dorsolateral prefrontal cortex (DLPFC) in memory recognition processes for positive versus negative emotional stimuli when old (target) and new (distractor, either semantically related or unrelated to the target) stimuli were presented. The role of the DLPFC was analysed using an rTMS (repeated transcranial magnetic stimulation) paradigm that induced increased cortical activation of the left DLPFC. The subjects were required to perform a task that consisted of two experimental phases (i.e., an encoding and a recognition phase) in which the targets and the distractors were presented and recognition performance was measured. rTMS stimulation was provided over the left DLPFC during the recognition phase. We found that the rTMS stimulation affected the memory recognition of positive emotional material. Moreover, related and unrelated distractors were discarded better when they were positively valenced, and a more significant effect (i.e., increased performance) was produced in response to related distractors. This result suggests that the activation of the left DLPFC favours the memory recognition of positive emotional information, and that such activation is able to induce a more appropriate selective process to distinguish target from distractor stimuli in the presence of more complex processes (related distractors). The valence model of emotional cue processing may explain this increased performance by demonstrating the distinct role of the left hemisphere in the retrieval of positive emotional information.  相似文献   
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In his paper “The Opposite of Human Enhancement: Nanotechnology and the Blind Chicken problem” (Nanoethics 2: 305-36, 2008) Thompson argued that technological attempts to reduce or eliminate selected non-human animals’ capabilities (animal disenhancements) in order to solve or mitigate animal welfare problems in animals’ use pose a philosophical conundrum, because there is a contradiction between rational arguments in favor of these technological interventions and intuitions against them. In her response “Animal Disenhancement and the Non-Identity Problem: A Response to Thompson” (Nanoethics 5:43–48, 2011), Palmer maintained that the philosophical conundrum is even deeper if we introduce the non-identity problem into the discussion. In my brief response, I claim that in order to avoid the pitfalls of speculative ethics, empirical facts related to the technologies involved as well as costs for the non-human animals have to be taken into account. Depending on which changes we are referring to, ethical problems can be seen very differently. Widening the consideration to the socio-economic context in which non-human animals are currently used by humans, I challenge the idea of genuine philosophical conundrums from an antispeciesist and abolitionist perspective. Only in a context of exploitation, in which non-human animals are deprived of basic rights and their existence is totally dependent on human exploitation, the contradictions between improvement of welfare and disenhancement of capabilities make sense.  相似文献   
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Stroke is one of the major causes of mortality and the most important cause of disability in the industrialized world. About 85?% of all strokes are caused by acute occlusion of a cerebral vessel and are, therefore, classified as ischemic stroke. Acute stroke care has seen substantial improvements in the last 20 years with the introduction of specialized acute care units (stroke units) and the implementation of intravenous thrombolysis with rtPA, which can be administered up to 4.5 h after symptom onset. According to recent evidence, even patients with age over 80 years, history of diabetes and stroke, wake up stroke, pretreatment with vitamin K antagonists, or one of the new oral anticoagulants could benefit from rtPA under specific conditions. A new therapeutic option for patients with a severe ischemic stroke could be the combined use of intravenous and intraarterial thrombolysis together with mechanical thrombectomy.  相似文献   
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Due to the high variability in predation risk through space and time, prey have to continuously update information about the risk level posed by predators. Despite numerous studies focusing on temporal risk assessment, we know very little about how individuals deal with information regarding changes in risk level of a given predator through time. In this study, we conditioned tadpoles to recognize a predator as a high or low risk twice 2 weeks apart, in a 2 × 2 design. We tested the responses of the tadpoles 1 and 11 days after each conditioning event. Prey showed responses to the predator 1 day after the first conditioning, but the low-risk group failed to respond to the predator after 11 days. However, we found that information learned during the first conditioning affected the response to the predator after the second conditioning, indicating that prey do not ‘forget’ old information, but simply ignore it. Moreover, tadpoles were able to assess their change in vulnerability over the 2-week period and further extrapolate the risk level of the predator through time to display adaptive threat-sensitive antipredator responses. Our study highlights the complex decision-making that prey use to assess temporal fluctuation in predation risk.  相似文献   
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