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111.
Age-related enhancement of a protein synthesis-dependent late phase of LTP induced by low frequency paired-pulse stimulation in hippocampus
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Protein synthesis-dependent late phase of LTP (L-LTP) is typically induced by repeated high-frequency stimulation (HFS). This form of L-LTP is reduced in the aged animal and is positively correlated with age-related memory loss. Here we report a novel form of protein synthesis-dependent late phase of LTP in the CA1 region of hippocampus induced by a brief 1-Hz paired-pulse stimulation (PP-1 Hz, 1 min). In contrast to L-LTP induced by HFS, the late phase of PP-1 Hz LTP does not exist in young adult animals. Rather, it emerges and becomes enhanced in an age-related way. Thus, in 1.5- to 2-mo-old mice, a brief PP-1 Hz stimulation induces only a short lasting LTP, decaying to baseline in about 90 min. By contrast, PP-1 Hz stimulation induces an enduring and protein synthesis dependent LTP in 12- to 18-mo-old mice. The PP-1 Hz-induced L-LTP is dependent on NMDA receptor activation, requires voltage-dependent calcium channels, and is modulated by dopamine D1/D5 receptors. Because memory ability declines with aging, the age-related enhancement of L-LTP induced by PP-1 Hz stimulation indicates that this form of L-LTP appears to be inversely correlated with memory ability. 相似文献
112.
This research presents four studies on the initial development and validation of the 48-item Negative Physical Self Scale (NPS), a multidimensional measure of body image concerns for use with Chinese samples. In Study 1 (N = 1095), exploratory factor analyses identified five dimensions underlying the NPS (General Appearance, Facial Appearance, Shortness, Fatness, Thinness). In Study 2 (N = 1057), confirmatory factor analyses replicated this factor structure. In Studies 3 and 4, the validity of all NPS dimensions except Thinness Concern was supported via their patterns of relation with both objective physical characteristics/behaviors and other self-report measures of body image and general self worth. Because Chinese adolescents and young adults expressed relatively more concerns about General Appearance, Shortness, and Facial Appearance than about Fatness, the NPS may have greater utility for assessing body image disturbances in China than existing measures that focus exclusively on general body satisfaction and body size/weight. 相似文献
113.
This study examined the effects of wrist rest and forearm support on reducing computer operators' activities using the trapezius, deltoid, biceps brachii, extensor carpi radialis longus, and extensor digitorum. 12 young (M= 25.9 yr., SD= 2.4) men were asked to perform both static and dynamic mouse operations in four conditions, two using a wrist rest and two using a forearm support. Analysis showed that use of the forearm support had a significant effect on reducing the EMG activity in muscles of the trapezius, deltoid, biceps brachii, extensor carpi radialis longus, and extensor digitorum. However, the wrist rest only significantly reduced deltoid and extensor carpi radialis longus activities. 相似文献
114.
This paper studies changes of standard errors (SE) of the normal-distribution-based maximum likelihood estimates (MLE) for
confirmatory factor models as model parameters vary. Using logical analysis, simplified formulas and numerical verification,
monotonic relationships between SEs and factor loadings as well as unique variances are found. Conditions under which monotonic
relationships do not exist are also identified. Such functional relationships allow researchers to better understand the problem
when significant factor loading estimates are expected but not obtained, and vice versa. What will affect the likelihood for
Heywood cases (negative unique variance estimates) is also explicit through these relationships. Empirical findings in the
literature are discussed using the obtained results. 相似文献
115.
How do humans use target-predictive contextual information to facilitate visual search? How are consistently paired scenic objects and positions learned and used to more efficiently guide search in familiar scenes? For example, humans can learn that a certain combination of objects may define a context for a kitchen and trigger a more efficient search for a typical object, such as a sink, in that context. The ARTSCENE Search model is developed to illustrate the neural mechanisms of such memory-based context learning and guidance and to explain challenging behavioral data on positive-negative, spatial-object, and local-distant cueing effects during visual search, as well as related neuroanatomical, neurophysiological, and neuroimaging data. The model proposes how global scene layout at a first glance rapidly forms a hypothesis about the target location. This hypothesis is then incrementally refined as a scene is scanned with saccadic eye movements. The model simulates the interactive dynamics of object and spatial contextual cueing and attention in the cortical What and Where streams starting from early visual areas through medial temporal lobe to prefrontal cortex. After learning, model dorsolateral prefrontal cortex (area 46) primes possible target locations in posterior parietal cortex based on goal-modulated percepts of spatial scene gist that are represented in parahippocampal cortex. Model ventral prefrontal cortex (area 47/12) primes possible target identities in inferior temporal cortex based on the history of viewed objects represented in perirhinal cortex. 相似文献
116.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
117.
Laura Jobson Nina Whittles Eleana Tsecoutanis Sanjana Raj Rui Ying Yew Shamsul Haque 《Memory (Hove, England)》2013,21(8):1054-1062
ABSTRACTCultural differences in autobiographical memory characteristics and function have often been presumed to be associated with different cultural beliefs related to the self. The current research aimed to investigate whether self-construal mediated the relationship between cultural group and the characteristics and functional use of autobiographical memory. Caucasian Australians (n?=?71) and Malay Malaysians (n?=?50) completed an online questionnaire that included the Self-Defining Memory task, the Thinking About Life Experiences Revised Questionnaire and the Self Construal Scale. As expected, the Australian group provided longer, more autonomously oriented, specific memories than the Malay group. However, contrary to our predictions, self-construal did not mediate the relationships between cultural group and memory characteristics. The Malay group reported more frequently using autobiographical memories for self-continuity than the Australian group. Finally, there was support for an indirect pathway between cultural group and use of autobiographical memories for self-continuity and social-bonding through self-construal (i.e. independent self relative to interdependent self). The findings highlight the importance of explicitly examining values assumed to be associated with autobiographical remembering, and relating these values to memory characteristics and function. 相似文献
118.
简要回顾了叙事疗法的诞生和在中国的传播过程,探讨了叙事疗法在三个方面的生命伦理学关怀:以生命权力的平等为前提、以人文生态的和谐为途径、以生命意义的丰富为旨归.最后探讨分析了叙事疗法的发展潜力,并指出叙事疗法所蕴含的生命伦理学关怀是一个重要的推动因素. 相似文献
119.
Nostalgic experience evokes emotions and activates the cognitive process of recalling and reconstructing information in memory. This study investigated the effects of nostalgia on creativity using experiments and questionnaires. Two-hundred-and-eighty university students were randomly assigned to experimental and control groups, in which participants received and completed different writing tasks (nostalgic experience vs. common life experience). They also responded to questionnaires measuring personality, nostalgia proneness, and creativity. Results showed that participants who were primed with nostalgic experience demonstrated higher creativity than the control group. In both groups, women demonstrated higher creativity than men. When specific aspects of the nostalgic experience were used to predict creativity, results showed that: (a) nostalgia triggered by social interaction and negative affect was positively related to creativity; (b) nostalgic experience containing tangibles positively predicted creativity; (c) the total number of triggers and the amount of, but not the positivity or salience of self in, nostalgia narrative contributed positively to creativity; and (d) higher agreeableness and openness, but not nostalgia proneness or other personality traits, were associated with higher creativity. Implications for both research and practice are discussed. 相似文献
120.
Piracy is the greatest threat facing the global music industry today. This study explores the effects of artist adoration and the perceived risk of being caught on the attitude and intention to engage in pirating a digital song among college students. The moderating effect of cultural environment factor is also examined. Experiments using between-group factorial designs were conducted in the United States and Taiwan. The results show that perceived risk of getting caught and cultural environment are important factors that can significantly affect the attitude and intention toward downloading unauthorized music. In addition, a two-way (Perceived Risk × Culture) and a three-way interaction in the model are also observed. 相似文献