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21.
Mueser Kim T.; Bellack Alan S.; Wade Julie H.; Sayers Steven L.; Tierney Ann; Haas Gretchen 《Canadian Metallurgical Quarterly》1993,102(3):339
Examined social skills and social perception of 48 schizophrenia/schizoaffective disorder patients (aged 18–55 yrs) in response to negative affect as a function of family expressed emotion (EE). Ss participated in a role-play test, a social perception test, and a problem-solving discussion with a family member and were assessed on several measures of symptomatology. EE of family members was evaluated with the Camberwell Family Interview. On the role-play test, Ss with less critical relatives became more assertive in response to increased negative affect from a confederate portraying either a family member or friend, but Ss with highly critical relatives did not. Ss with highly critical relatives were also less assertive when confronted with negative affect from a confederate portraying a family member rather than a friend. The behaviors of both relatives and Ss during a family problem-solving interaction were related to the EE dimensions of criticism, emotional overinvolvement, and warmth. Patient gender was also related to family problem solving but was independent of EE. S's ratings of affect on a videotaped social perception task were not related to family EE, and there were few differences in psychopathology between Ss with high and low EE relatives.… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
The purpose of this study was to examine the relationships between computer use, identity formation, and self-esteem among Black and White emerging adult females. One hundred 56 female college students participated in this study by completing a survey that included the Internet/Computer Use Questionnaire, the Ego Identity Process Questionnaire, and the Rosenberg Self Esteem Scale. Racial differences were found between Black and White females with regard to perceived problematic use of the Internet and use of the computer for communication and use of the Internet for schoolwork. In addition, differences between Black and White females were found between identity formation and problematic use of the Internet and between self-esteem and type of use of the Internet. These findings were discussed in relation to future research and interventions. 相似文献
23.
An overview of FDA medical device regulation as it relates to deep brain stimulation devices. 总被引:1,自引:0,他引:1
Carlos Pe?a Kristen Bowsher Ann Costello Robert De Luca Sara Doll Khan Li Marie Schroeder Theodore Stevens 《IEEE transactions on neural systems and rehabilitation engineering》2007,15(3):421-424
The United States Food and Drug Administration (FDA) is charged with assuring the safety and effectiveness of a variety of medical products and the FDA's Center for Devices and Radiological Health is responsible for premarket and postmarket regulation of medical devices. In this paper, we review--from device classification and clinical studies to the final marketing application--FDA's premarket requirements and postmarket requirements as they relate to deep brain stimulation devices. 相似文献
24.
Bovine growth hormone was administered to eight Holstein cows during two 10-d periods (commencing 20 and 60 d postpartum). Treatments involved daily subcutaneous injection of excipient (control) or of 50 IU growth hormone. Feed intake and yields of milk and milk components were measured during the last 5 d of treatment. In the first injection period, milk yield of treated cows was 6% greater than that of controls (36.2 kg/d). Fat content of milk was increased by treatment with the result that fat yield was elevated by 25%. Protein content was not altered. In the second period, milk yield increased by 12%, but composition of milk was not changed. As a result, milk energy secretion was increased by a similar amount in each treatment period (4.4 versus 4.5 Mcal/d). Feed intake was not changed in either period. During early lactation the ability of cows to increase milk yield in response to exogenous growth hormone may be limited by the supply of glucose for lactose synthesis rather than by ability to mobilize body reserves in support of lactation. 相似文献
25.
Many new speciality polymers have been developed in the last few years. In this paper polymeric stabilizers (antioxidants, flame retardants and ultraviolet stabilizers) will be discussed. Polymeric antioxidants of the hindered-phenol type, copolymers of 2,6-ditertiarybutyl-4-vinyl(or isopropenyl)phenol with styrene, methyl methacrylate, or more importantly butadiene or isoprene have been prepared; hydrogenation of the latter copolymers gave copolymers of the two polymerizable phenolic antioxidants with ethylene or ethylene/propylene. The polymeric antioxidants have been blended with diene polymers and selected polyolefins and have improved the long-term oxidative stability of these polymers. Polymeric flame retardants have been prepared by copolymerizing styrene and/or acrylonitrile with acrylates and methacrylates of aliphatic bromine-containing alcohols or bromine-containing phenols. Polymers with polymer-bound flame retardants have a higher limiting oxygen index compared with the original polymer. A new class of polymerizable ultraviolet stabilizers has also been developed; these stabilizers are styryl, α-methylstyryl, acryloyl and methacryloyl derivatives of 2(2-hydroxyphenyl)2H-benzotriazoles. These monomers have been copolymerized with styrene, acrylates and methacrylates. 2(2-Hydroxyphenyl)2H-benzotriazoles substituted in the 4 position of the benzotriazole ring with hydroxyl, acetoxy or carboxyl groups suitable for incorporation into polyesters, polycarbonates, polyamides and epoxy resins have also been synthesized. All 2(2-hydroxyphenyl)2H-benzotriazole ultraviolet absorbers and the polymers into which they are incorporated have high light absorbency with γmax between 330 and 350 nm and extinction coefficients in some cases as high as 4.5 × 104 1 mol?1 cm?1. 相似文献
26.
Keon Woo Kang Jaemin Ann Hwang Soo Lee 《Electronics letters》1994,30(25):2153-2154
The authors propose a method to estimate the synchronisation offset for orthogonal frequency division multiplexing (OFDM) frame alignment without resort to pilot tones. A decision-directed maximum-likelihood estimation of frame synchronisation offset is derived, and the performance of the proposed scheme is confirmed by computer simulation for QAM systems 相似文献
27.
In an effort to better understand the educational experiences and professional issues facing women in these fields, a survey of women alumnae was conducted. Respondents seemed fairly pleased with the education they received and were heavily influenced by personal aspects of the campus. Relationships with faculty members were described as their most beneficial and detrimental experiences. They particularly liked opportunities to apply their technical knowledge but did not believe there were enough opportunities for application. The need for more female role models and importance of involvement in student organizations were cited by many of the respondents. Self-confidence and good communication skills were rated as the most important qualities for professional success and advancement. Alumnae have pursued training experiences since graduation, but would like to see more opportunities to enhance communication and personal management skills and apply theoretical knowledge built into the undergraduate experience. The findings are discussed in relationship to previous research studies and recommendations are made to improve the technically oriented college environment. 相似文献
28.
Examined whether male and female students of high mathematical ability use different solution strategies on math problems that had previously yielded gender differences in correct responding. Structured interviews were conducted with high school students who had scored at least 670 on the math portion of the Scholastic Aptitude Test (SAT-M). Eight types of solution strategies could be further dichotomized as conventional or unconventional in approach. Female students were more likely than male students to use conventional strategies. SAT-M scores were correlated with positive attitudes (confidence and persistence) toward math: use of conventional strategies was correlated with negative attitudes (dislike, nonrelevance) toward math. Findings may help to explain patterns of gender differences on SAT-M problems among high-ability students in which female students outperform male students on conventional problems and male students outperform female students on unconventional problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Children (aged 5–6 and 9–10 yrs) and adults participated in an eventful laboratory session and provided memory reports of the session. In 3 experiments, college students and parents viewed videotapes of highly accurate and highly inaccurate reports. In 2 experiments, these "fact finders" rated adult witnesses more believable and accurate than younger child witnesses, even when both groups were equally accurate. Perceptions of confidence and consistency mediated credibility judgments. Accurate witnesses were judged more believable and accurate than inaccurate witnesses. Higher perceived confidence, longer free recall, and fewer memory failure admissions were associated with more accurate adult memory reports. Fact finders overused confidence and underused the other cues in achieving modest accuracy discernment. The results suggest how strong and weak memory reports differ and how fact finders may learn to differentiate them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
The knots and weights of a cubature formula are determined by a system of nonlinear equations. The number of equations and unknowns can be reduced by imposing some structure on the formula. We are concerned with the construction of cubature formulae which are invariant under rotations. Using invariant theory, we obtain a smaller system of algebraically independent equations. This is used to construct cubature formulae for the square. One of the results is a 24-point formula of degree 11. 相似文献