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61.
62.
In positive social contexts, both adults and older infants show more Duchenne smiling (which involves high cheek raising) than non-Duchenne smiling (which does not). This study compared Duchenne and non-Duchenne smiles in early infancy for clues to their emotional significance. Infants (N?=?13) from 1 to 6 months of age were videotaped weekly for 5 min in 208 face-to-face interactions with their mothers. Levels of Duchenne and non-Duchenne smiling were correlated within interactive sessions, and the 2 smiles had similar developmental trajectories. Duchenne smiles were typically preceded by non-Duchenne smiles. The results suggest these frequently contrasted types of smiles occur in similar situations and are often different temporal phases of a continuous emotional process. In contrast to adults, infant Duchenne smiles had longer durations than non-Duchenne smiles, suggesting infant smiling does not fit adult models of emotional functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
This study examined the overarching issue of how temporal transitions, specifically duration of message flow, affects momentum or wellness of discussion in an asynchronous forum. Quantitative data representing time indicators in discussion activity included posting patterns related to duration (density, intensity, latency, and response count), Day-In topic, day of week, and time of day. Qualitative analysis identified notable spikes or irregularities (i.e., peaks and valleys) in the content level of postings. Results revealed that for open-ended topics (i.e., no specific end date imposed by the instructor), the momentum of forum discussion may be short-term, between 21 and 28 days into the topic. Peaks and valleys subsequent to 31 days were not significant to discussion vitality. Students posted mainly early to mid-week. Time of day had no direct influence on the vitality of the discussion. Strategies for applying temporal transitions in an online forum to motivate and sustain student participation are discussed. 相似文献
64.
65.
Lisa Borre David R. Barker Laurie E. Duker 《Lakes & Reservoirs: Research and Management》2001,6(3):199-209
The conceptual framework for lake management has evolved at an accelerating rate in recent years to include the basic principles of a watershed approach: (i) citizen and stakeholder involvement is important throughout the planning and management process; (ii) the geographic focus for management activities includes the lake and its entire watershed; and (iii) mechanisms need to be in place to promote cooperation among different government jurisdictions and organizations in the watershed. Creating effective institutional arrangements for implementing this watershed approach in lake regions is perhaps the most challenging and important issue facing the world’s lakes. LakeNet organized a workshop at the 8th International Conference on the Conservation and Management of Lakes in May 1999. This article is a synthesis of the results of the workshop and the eight case reports prepared by the workshop participants published in this special issue. Seven major threats to lakes were identified: (i) accelerated eutrophication; (ii) invasive species; (iii) toxic contamination; (iv) overfishing; (v) water diversion, (vi) acidification; and (vii) climate change. Institutions and institutional arrangements for addressing these issues and for implementing a watershed approach are just beginning to emerge on lakes around the world. All of the institutions described in the case reports were established or formalized during the 1980s and 1990s. The legal mechanisms creating these institutions range from cooperative agreements among jurisdictions for purposes of policy and planning to national laws and international treaties with full regulatory powers. The knowledge base, political will and financial resources for these activities were very small in comparison with the complexity of the task at hand. 相似文献
66.
Describes an empirically common pattern in intimate relationships in which men and women attach a different significance to the act of sexual intercourse (establishing vs acknowledging an already established closeness and affirmation). The consequences for relationships involve negative views of self and partner. Therapeutic recommendations are given for working with couples for whom this misunderstanding exists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
This study was the first to establish Diagnostic and Statistical Manual of Mental Disorders (DSM—IV; American Psychiatric Association, 1994) prevalence rates for eating disorders by targeting an entire sample of African American college women. Participants were 413 African American women enrolled at a large, predominantly Caucasian public university in the midwestern United States. Participants were given the Questionnaire for Eating Disorder Diagnoses (L. B. Mintz, M. S. O'Halloran, A. M. Mulholland, & P. A. Schneider, 1997). No respondents were classified as having anorexia nervosa or bulimia nervosa, and 2% were classified as having an eating disorder not otherwise specified. Twenty-three percent were classified as symptomatic. Although there is some evidence that these prevalence rates may be underestimated, they are nevertheless in the same range as those obtained for comparative Caucasian samples. Implications for future research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Guillaume Bernard-Granger Christian Guizard Laurie San-Miguel 《Journal of the American Ceramic Society》2007,90(9):2698-2702
Sintering in air of a pure yttria powder was investigated on green samples shaped by slip casting. The "relative density/grain size" trajectory has been drawn and hypotheses concerning the mechanisms controlling grain growth and densification were formulated. Samples were fully densified by an additional hot isostatic pressing step on pre-sintered samples. After optimal polishing, optical properties were measured in the UV, visible, and infrared ranges. 相似文献
69.
McCarroll James E.; Thayer Laurie E.; Liu Xian; Newby John H.; Norwood Ann E.; Fullerton Carol S.; Ursano Robert J. 《Canadian Metallurgical Quarterly》2000,68(3):521
Recidivism by spouse abusers was investigated using records of offenders in the U.S. Army Central Registry. Recidivism by gender and military status (active-duty or civilian spouse) was compared over a 70-month period. Between fiscal years 1989–1997, 48,330 offenders were identified in initial and recidivist incidents. Recidivism was analyzed by means of a Cox proportional hazard rate model, controlling for age, race, number of dependents, education, and substance abuse. Two different sets of survival curves were obtained: (a) Men were much more likely than women to have a recurrence and (b) within gender, civilians were more likely to have a recurrence than were active-duty military personnel. At 70 months, 30% of the male civilian offenders and 27% of the male active-duty offenders had committed a subsequent spouse abuse incident compared with 20% of the female civilian offenders and 18% of the female active-duty offenders, controlling for other variables. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Effects of Zirconia on Microstructure and Dielectric Properties of Barium Titanate Ceramics 总被引:1,自引:0,他引:1
Timothy R. Armstrong Laurie E. Morgens Alena K. Maurice Relva C. Buchanan 《Journal of the American Ceramic Society》1989,72(4):605-611
Dielectric properties and structural characteristics of BaTiO3 ceramics are significantly influenced by small addition (2 wt%) of ZrO2 . SEM and TEM observations revealed enhanced microstructural uniformity and retarded grain growth depending on sintering temperature. Above 1320°C, Zr diffusion into the BaTiO3 lattice resulted in a chemical modification of the tetragonal structure and the development of core–shell grains. Below 1320°C, TEM analysis showed ZrO2 at the grain boundaries as discrete particles (∼0.03μm). X-ray diffraction analysis revealed a decrease in the axial (c/a) ratio with decreasing grain size. A corresponding decrease in the spontaneous polarization, and twinned domain structures, were also observed in the fine-grained ceramics. These samples also showed a flattened permittivity response with temperature and significantly lower losses. 相似文献