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811.
32 women pseudoclients from each of 2 age groups (25–35 and 60–70 yrs) met with a woman crisis counselor from 1 of the 2 age groups for a 50-min face-to-face interview. Results suggest that age of clients and counselors did not exert a significant influence on clients' perceptions of counselor facilitative skills (e.g., empathy, congruence, regard) or client satisfaction with the therapeutic interview. Age similarity between the client and counselor did not necessarily improve the working alliance. Clients of a specific age group view some counselors of a particular age as more facilitative and empathic than other counselors of that same age. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
812.
Asserts that changes set in motion by major public health advances early in the century have increased the demand for knowledge about the aging process, especially the psychological aspects of aging. There is need for basic and applied research on aging in areas such as memory; federal support should be provided for training at the predoctoral level; and information on the psychological aspects of aging should be transmitted to society, policy makers, and members of other professions who serve the elderly. Knowledge of aging as a biological, psychological, and social process is applicable in fields such as industry, education, and engineering. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
813.
Examined A. Bandura's (see record 1977-25733-001) self-efficacy theory of mastery behavior, which distinguishes self-efficacy expectancies (SEEs) from outcome expectancies (OEs), by the relative roles of SEEs, OEs, and importance as predictors of persistence of pain control in medication-free childbirth. 52 primiparous women made self-efficacy judgments before and during labor and then reported in postdelivery interviews the timing and amount of medication use during labor and delivery. SEEs predicted persistence in pain control without medication better than OEs, importance, and 7 other alternative predictors. These results support several aspects of construct validation to the SEE construct. However, SEEs and OEs were highly correlated and largely redundant in their correlations with mastery. Three possible reasons and implications for this lack of differentiation are discussed. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
814.
Carlson SE  Neuringer M 《Lipids》1999,34(2):171-178
The rationale for randomized trials designed to measure the effects of variable docosahexaenoic acid (DHA) status on neurodevelopment in human infants came from earlier studies of neurodevelopment in animals that were deficient in DHA owing to diets low in alpha-linolenic acid. The session on neurodevelopment looked at the results of these animal studies and discussed outcomes that appear to be analogous in human infants with variable DHA status. Presentations focused mainly on measures of development that may be attributed to more specific developmental domains (e.g., visual attention, recognition memory, problem-solving), some of which have been shown to be affected by long-chain polyunsaturated fatty acid (LCPUFA) status. This paper derives from discussions that took place during the session and reviews subsequent developments in this area. Although more difficult to interpret, global measures of infant development (e.g., the Bayley Scales of Infant Development, and Brunet-Lezine) can only suggest a relationship to specific developmental domains, but they have been applied in some randomized trials of LCPUFA and infant development. Those results are also summarized here.  相似文献   
815.
Over the last twenty years, there has been a discernable increase in the number of scholars who have focused their research on metal production, working and use in antiquity, a field of study which has come to be known as archaeometallurgy. Materials scientists and conservators have worked primarily in the laboratory while archaeologists have conducted fieldwork geared to the study of metal technology in a cultural context with laboratory analysis as one portion of the interpretive program.  相似文献   
816.
This paper compares three remote sensing-based models for estimating evapotranspiration (ET), namely the Surface Energy Balance System (SEBS), the Two-Source Energy Balance (TSEB) model, and the surface temperature-vegetation index Triangle (TVT). The models used as input MODIS/TERRA products and ground measurements collected during the wheat and corn growth period in a subhumid climate at a measurement station in Yucheng, China. MODIS land surface temperature (LST) and leaf area index (LAI) products, corrected using ground-truth observations, were used in the three models. The TSEB model output of sensible (H) and latent (LE) heat fluxes were in good agreement with Large Aperture Scintillometer (LAS)-measured H and LE derived by residual (RMSD < 45 W/m2). Reasonable agreement was also obtained with the SEBS model output yielding RMSD for H of ~ 40 W/m2 and LE ~ 55 W/m2. However, the TVT model output resulted in poor agreement with the LAS-estimated H and LE with RMSD-values > 110 W/m2. Using the uncorrected MODIS LST and LAI products resulted in a deterioration of the agreement in H and LE with LAS-estimated values for both the TSEB and SEBS models, whereas TVT performance improved marginally. These results indicate that the TSEB model yielded the closest agreement with the LAS-estimated fluxes using either the corrected or uncorrected MODIS inputs (LST and LAI). The SEBS model also computed reasonable H and LE values but was significantly more sensitive to errors in MODIS LST and LAI inputs than the TSEB model. In the TVT model, output of H and LE was unacceptable in either scenario of MODIS input which was attributable to errors in selection of the dry edge. With the TVT method, accurate determination of the dry edge end member is critical in regional ET estimation, but for humid and subhumid regions this end member may often be quite difficult to identify or encompass within a satellite scene.  相似文献   
817.
Arctic vegetation distribution is largely controlled by climate, particularly summer temperatures. Summer temperatures have been increasing in the Arctic and this trend is expected to continue. Arctic vegetation has been shown to change in response to increases in summer temperatures, which in turn affects arctic fauna, human communities and industries. An understanding of the relationship of existing plant communities to temperature is important in order to monitor change effectively. In addition, variation along existing climate gradients can help predict where and how vegetation changes may occur as climate warming continues. In this study we described the spatial relationship between satellite-derived land surface temperature (LST), circumpolar arctic vegetation, and normalized difference vegetation index (NDVI). LST, mapped as summer warmth index (SWI), accurately portrayed temperature gradients due to latitude, elevation and distance from the coast. The SWI maps also reflected NDVI patterns, though NDVI patterns were more complex due to the effects of lakes, different substrates and different-aged glacial surfaces. We found that for the whole Arctic, a 5 °C increase in SWI along the climate gradient corresponded to an increase in NDVI of approximately 0.07. This result supports and is of similar magnitude as temporal studies showing increases of arctic NDVI corresponding to increases in growing season temperatures over the length of the satellite record. The strongest positive relationship between NDVI and SWI occurred in partially vegetated and graminoid vegetation types. Recently deglaciated areas, areas with many water bodies, carbonate soil areas, and high mountains had lower NDVI values than predicted by SWI. Plant growth in these areas was limited by substrate factors as well as temperature, and thus is likely to respond less to climate warming than other areas.  相似文献   
818.
When searching for blogs on a specific topic, information seekers prefer blogs that place a central focus on that topic over blogs whose mention of the topic is diffuse or incidental. In order to present users with better blog feed search results, we developed a measure of topical consistency that is able to capture whether or not a blog is topically focused. The measure, called the coherence score, is inspired by the genetics literature and captures the tightness of the clustering structure of a data set relative to a background collection. In a set of experiments on synthetic data, the coherence score is shown to provide a faithful reflection of topic clustering structure. The properties that make the coherence score more appropriate than lexical cohesion, a common measure of topical structure, are discussed. Retrieval experiments show that integrating the coherence score as a prior in a language modeling-based approach to blog feed search improves retrieval effectiveness. The coherence score must, however, be used judiciously in order to avoid boosting the ranking of irrelevant but topically focused blogs. To this end, we experiment with a series of weighting schemes that adjust the contribution of the coherence score according to the relevance of a blog to the user query. An appropriate weighting scheme is able to improve retrieval performance. Finally, we show that the coherence score can be reliably estimated with a sample exceeding 20 posts in size. Consistent with this finding, experiments show that the best retrieval performance is achieved if coherence scores are used when a blog contains more than 20 posts.  相似文献   
819.
This paper presents a high-performance broad-coverage supervised word sense disambiguation (WSD) system for English verbs that uses linguistically motivated features and a smoothed maximum entropy machine learning model. We describe three specific enhancements to our system’s treatment of linguistically motivated features which resulted in the best published results on SENSEVAL-2 verbs. We then present the results of training our system on OntoNotes data, both the SemEval-2007 task and additional data. OntoNotes data is designed to provide clear sense distinctions, based on using explicit syntactic and semantic criteria to group WordNet senses, with sufficient examples to constitute high quality, broad coverage training data. Using similar syntactic and semantic features for WSD, we achieve performance comparable to that of human taggers, and competitive with the top results for the SemEval-2007 task. Empirical analysis of our results suggests that clarifying sense boundaries and/or increasing the number of training instances for certain verbs could further improve system performance.
Martha S. PalmerEmail:
  相似文献   
820.
A polyester containing diacetylenic units in main chain was prepared by the polycondensation of m, m-butadiynylene dibenzyl alcohol with terephthaloyl chloride. The polymer was crystalline, and bearly soluble in hot dimethylformamide or dimethylsulfoxide, but insoluble in most organic solvents. It melts at about 200°C. Irradiation of UV light at 75°C gave a reddish brown resin. Heating at temperatures above its melting point gave a shinning black hard solid.  相似文献   
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