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71.
The APA Insurance Trust is pleased to announce the establishment of a new Group Life Insurance Program for APA members and their families. The new program represents more than a year of intensive investigation and many months of negotiation with leading insurance carriers. A few highlights of the program are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
A comparative study of tyrosine phosphorylation was performed on peripheral blood lymphocytes from systemic lupus erythematosus (SLE) patients and from healthy donors. Freshly isolated SLE lymphocytes presented an elevated tyrosine phosphorylation level when compared to healthy donors lymphocytes (p = 0.005). Among all phosphorylated proteins, those called p120, p110, p80 and p55-p60 were more phosphorylated. The level of tyrosine phosphorylation of p120 and p110 proteins discriminated significantly (p = 0.0048, respectively, p = 0.02) between SLE patients and healthy donors. Lymphocytes form SLE patients and healthy donors were then stimulated by cross-linking T cell antigens (CD3, CD4, CD8) to further distinguish the signal transduction between normal and pathologic lymphocytes. No statistical differences in the tyrosine phosphorylation pattern, following CD4 or CD8 cross-linking, were observed between SLE patients and healthy donors lymphocytes. CD3 cross-linking induced an effect on tyrosine phosphorylation different in SLE patients versus healthy donors lymphocytes. Thus, the lymphocytes of SLE patients were refractile in anti-CD3 stimulation in comparison with the healthy donors lymphocytes. Chi-square analysis demonstrated that a significantly larger number of healthy donors responded to anti-CD3 stimulation compared to SLE patients (p = 0.03). The high frequency of tyrosine phosphorylation of p110 and p80 proteins, following CD3 stimulation, in normal versus SLE lymphocytes, suggested that these proteins could be involved in abnormal signal transduction in SLE cells.  相似文献   
73.
36 3-mo-old infants interacted with their mothers under conditions in which they could see and hear their mothers (correlated auditory plus visual information: A?+?V), see but not hear their mothers (V), and hear but not see their mothers (A); the latter 2 conditions are termed perceptual paradox. The interactions were videotaped, and the Ss' behavior was judged by naive observers who used a subjective 7-point rating scale of infant affect. For 2 groups of Ss, 3 1-min presentations of the A?+?V condition were alternated with 3 1-min presentations of either A (Group 1) or V (Group 2) conditions. In both groups, Ss were judged as being more distressed during unimodal presentations than during bimodal presentations. In a 3rd group, unimodal (A) presentations were alternated with unimodal (V) presentations. Ss in this group were significantly more distressed when they could hear but not see their mothers than when they could see but not hear their mothers. Results demonstrate the suitability of global subjective ratings of affective state in studies of infant perception. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
At times, people keep their emotions from showing during social interactions. The authors' analysis suggests that such expressive suppression should disrupt communication and increase stress levels. To test this hypothesis, the authors conducted 2 studies in which unacquainted pairs of women discussed an upsetting topic. In Study 1, one member of each pair was randomly assigned to (a) suppress her emotional behavior, (b) respond naturally, or (c) cognitively reappraise in a way that reduced emotional responding. Suppression alone disrupted communication and magnified blood pressure responses in the suppressors' partners. In Study 2, suppression had a negative impact on the regulators' emotional experience and increased blood pressure in both regulators and their partners. Suppression also reduced rapport and inhibited relationship formation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Prepulse inhibition (PPI) of the startle reflex refers to the reduction of the reflexive startle response to an intense pulse stimulus when its presentation is shortly preceded by a weak prepulse stimulus. PPI is considered as a cross-species translational model of sensorimotor gating, and deficient PPI has been reported in a number of neuropsychiatric disorders. Although a part of the literature is based on the assumption that PPI is independent of the baseline startle reaction, there is accumulating evidence (Csomor et al., 2006; Sandner & Canal, 2007; Yee, Chang, Pietropaolo, & Feldon, 2005) that argues against such an independency. The authors systematically investigated whether PPI indexed as percentage or difference score is dependent on the magnitude of baseline startle reactivity in healthy human volunteers and in C57BL/6 mice. The results revealed that both indexations of PPI were affected by the magnitude of the baseline startle. The authors highlight the pitfalls of different methods to index PPI, especially when startle reactivity differs considerably between groups under comparison, and offer practical recommendations to satisfactorily deal with such baseline differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
79.
The aim of this work is examining the influence of the number of the activation––over-voltage pulses to the aging of over-voltage protection elements. Both non-linear (gas-filled surge arresters (GFSA), varistors, over-voltage diodes) and linear (capacitors––constituents of filters) over-voltage protection elements were tested. The instruments employed allow reliable measurements, 1000 consecutive activation were tested. The double-exponential current pulse (amplitude I1max=13 A, I2max=16 A, rise time T1=8 μs, fall time T2=20 μs) for non-linear elements and a double-exponential over-voltage pulse (rise time T1=1.2 μs, fall time T2=50 μs) of the amplitude U1max=320 V, U2max=480 V and U3max=640 V for capacitors were used. The experimental results show that the over-voltage diodes are the most reliable elements in view of characteristic modifications that are consequence of aging. However, it was observed that varistors, GFSA and capacitors undergo noticeable changes in characteristics.  相似文献   
80.
A broad-band transmission line model for a rectangular microstripantenna   总被引:1,自引:0,他引:1  
A method is developed using the transmission line model to predict the input characteristics of rectangular microstrip antennas over a wide band of frequencies. A series combination of transmission lines is used to represent each transverse magnetic (TM) model. Following a brief summary of the basic transmission line model, the idea of an equivalent length, width, and feed offset are introduced to model each mode. The results predicted by the model compared well with experimental results that assumed varying feed positions. The concept of equivalent length, width, and feed offset was validated by experimental results but shows that the equivalent offset term needs some improvement. The number of modes incorporated in the model depends on the frequency range over which the antenna must be modeled. Using three transmission lines gives good results up to the frequency at which the TM02 mode is excited  相似文献   
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