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31.
The effects of picture manipulations on humans' and pigeons' performance were examined in a go/no-go discrimination of two perceptually similar categories, cat and dog faces. Four types of manipulation were used to modify the images. Mosaicization and scrambling were used to produce degraded versions of the training stimuli, while morphing and cell exchange were used to manipulate the relative contribution of positive and negative training stimuli to test stimuli. Mosaicization mainly removes information at high spatial frequencies, whereas scrambling removes information at low spatial frequencies to a greater degree. Morphing leads to complex transformations of the stimuli that are not concentrated at any particular spatial frequency band. Cell exchange preserves high spatial frequency details, but sometimes moves them into the "wrong" stimulus. The four manipulations also introduce high-frequency noise to differing degrees. Responses to test stimuli indicated that high and low spatial frequency information were both sufficient but not necessary to maintain discrimination performance in both species, but there were also species differences in relative sensitivity to higher and lower spatial frequency information.  相似文献   
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Chris Fraser 《亚洲哲学》2008,18(2):123-147
Three views of psychological emptiness, or xū, can be found in the Zhuāngz?. The instrumental view values xū primarily as a means of efficacious action. The moderate view assigns it intrinsic value as an element of one Zhuangist vision of the good life. The radical view also takes it to be an element of the ideal life, but in this case the form of life advocated is that of the Daoist sage, who transcends mundane human concerns to merge with nature or the Dào. The instrumental and moderate views articulate a relatively commonsensical position, on which the agent continues to pursue at least some characteristically human projects. On the radical view, by contrast, the agent ceases to exercise agency and lives a life hardly recognizable as human. The three views thus signal a tension in Zhuangist ethics, and the unattractiveness of the radical view poses a potential obstacle to the application of Daoist ideas in contemporary ethical discourse. The paper argues that there are principled grounds within Zhuangist thought for detaching the instrumental and moderate views from the radical view and rejecting the latter.  相似文献   
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Hair analysis has been used to reflect long-term systemic exposure to exogenous drugs and toxins. Several studies have demonstrated the feasibility of measuring endogenous steroid hormones, e.g. cortisol, in hair. Recently, a study in macaques showed a significant increase in hair cortisol levels induced by stress. We explored whether hair cortisol levels may be used as a biomarker for long-term stress in humans. Patients with severe chronic pain, aged 18 years or older, receiving opioid treatment for at least one year were recruited. Controls were non-obese (body mass index, BMI < 30 mg/kg(2)) adults. The Perceived Stress Scale (PSS) questionnaire was used to assess perceived stress over the last 4 weeks. A hair sample was obtained from the vertex posterior. Cortisol was measured using an enzyme-linked immunosorbent assay. We included fifteen patients (nine females and six males) and 39 non-obese control subjects (20 females, 19 males). PSS scores (median and range) were significantly higher in chronic pain patients (24: 12-28) than in controls (12: 3-31)(P < 0.001). Hair cortisol contents (median and range) were significantly greater in chronic pain patients (83.1: 33.0-205 g/mg) than in controls (46.1: 27.2-200 pg/mg) (P < 0.01). We conclude that hair cortisol contents are increased in patients with major chronic stress. Measurement of cortisol levels in hair constitutes a novel biomarker of prolonged stress.  相似文献   
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Although the philosophical literature on the foundations of quantum field theory recognizes the importance of Haag’s theorem, it does not provide a clear discussion of the meaning of this theorem. The goal of this paper is to make up for this deficit. In particular, it aims to set out the implications of Haag’s theorem for scattering theory, the interaction picture, the use of non-Fock representations in describing interacting fields, and the choice among the plethora of the unitarily inequivalent representations of the canonical commutation relations for free and interacting fields.  相似文献   
36.
ABSTRACT— It is well established that animal communication signals have adapted to the evolutionary pressures of their environment. For example, the low-frequency vocalizations of the elephant are tailored to long-range communications, whereas the high-frequency trills of birds are adapted to their more localized acoustic niche. Like the voice, the human face transmits social signals about the internal emotional state of the transmitter. Here, we address two main issues: First, we characterized the spectral composition of the facial features signaling each of the six universal expressions of emotion (happiness, sadness, fear, disgust, anger, and surprise). From these analyses, we then predicted and tested the effectiveness of the transmission of emotion signals over different viewing distances. We reveal a gradient of recognition over viewing distances constraining the relative adaptive usefulness of facial expressions of emotion (distal expressions are good signals over a wide range of viewing distances; proximal expressions are suited to closer-range communication).  相似文献   
37.
This study investigated whether semantic information presented along with novel printed nonwords facilitates orthographic learning and examined predictors of individual differences in this important literacy skill. A sample of 35 fourth graders was tested on a variety of language and literacy tests, and participants were then exposed to 10 target nonwords, 5 of which were presented with semantic information. Children were tested 1 and 4 days later on their ability to correctly recognize and spell the target nonwords. Results revealed a significant main effect on the recognition task, where items presented with semantic information were identified correctly more often than were words presented in isolation. No significant effect of training condition was found for the spelling posttests. Furthermore, multiple regression analyses revealed that both phonological and semantic factors were significant predictors of orthographic learning. The findings support the view that orthographic learning, as measured through visual recognition, involves the integration of phonological, orthographic, and semantic representations.  相似文献   
38.
Emotional availability (EA) was investigated among low‐income mothers enrolled in substance‐abuse treatment and their young infants (n = 21) compared with a demographically matched group of mother–infant pairs who, by self‐report, were not at risk for substance abuse (n = 27). The mother–infant dyads in the treatment group generally demonstrated poorer EA functioning than those in the comparison group, but few differences between the groups on individual dimensions of EA were significant. This finding was notable considering that mothers in treatment reported significantly higher levels of depressive symptoms and psychological stress. Treatment effects may have buffered the negative impact of depression and psychological stress on mothers' EA scores. The clinical implications of the findings are discussed as they relate to substance‐abuse‐treatment services for pregnant and parenting women.  相似文献   
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A survey of course titles in African American Studies departments and programs was conducted to examine the course offerings on the psychology of women, the psychology of African American women, and other areas of psychology as well as courses on gender from other disciplines. A total of 82 programs or departments of African American Studies and 182 courses were listed. The course discipline was stated in the majority of courses, with psychology having the most courses. Only a small percentage of the psychology courses listed gender in addition to race in the title. Of those courses listed in psychology, the majority were in social, developmental, or clinical psychology. The disciplines of English, sociology, history, and political science had listings of courses with both gender and race titles. This small survey indicates that the psychology of women has not had much influence on the curriculum of African American Studies. Possible reasons for this are discussed, as are solutions to this problem.  相似文献   
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