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81.
From birth, infants are exposed to a wealth of emotional information in their interactions. Much research has been done to investigate the development of emotion perception, and factors influencing that development. The current study investigates the role of familiarity on 3.5-month-old infants' generalization of emotional expressions. Infants were assigned to one of two habituation sequences: in one sequence, infants were visually habituated to parental expressions of happy or sad. At test, infants viewed either a continuation of the habituation sequence, their mother depicting a novel expression, an unfamiliar female depicting the habituated expression, or an unfamiliar female depicting a novel expression. In the second sequence, a new sample of infants was matched to the infants in the first sequence. These infants viewed the same habituation and test sequences, but the actors were unfamiliar to them. Only those infants who viewed their own mothers and fathers during the habituation sequence increased looking. They dishabituated looking to maternal novel expressions, the unfamiliar female's novel expression, and the unfamiliar female depicting the habituated expression, especially when sad parental expressions were followed by an expression change to happy or to a change in person. Infants are guided in their recognition of emotional expressions by the familiarity of their parents, before generalizing to others. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
82.
Learning object identification rules for information integration   总被引:2,自引:0,他引:2  
When integrating information from multiple websites, the same data objects can exist in inconsistent text formats across sites, making it difficult to identify matching objects using exact text match. We have developed an object identification system called Active Atlas, which compares the objects’ shared attributes in order to identify matching objects. Certain attributes are more important for deciding if a mapping should exist between two objects. Previous methods of object identification have required manual construction of object identification rules or mapping rules for determining the mappings between objects. This manual process is time consuming and error-prone. In our approach. Active Atlas learns to tailor mapping rules, through limited user input, to a specific application domain. The experimental results demonstrate that we achieve higher accuracy and require less user involvement than previous methods across various application domains.  相似文献   
83.
In this study, the authors explored potential strain and sex differences in nonspatial cognitive ability. Beginning around 90 days of age, male and female C57BL/6J (C57) and DBA/2J (DBA) inbred mice (Mus musculus) were tested on a task of simple odor discrimination learning with 3 repeated reversals. Males learned the task more readily than females, and DBA mice learned the task more readily than C57 mice. All differences became evident after repeated testing. Similarity of perseveration measures indicated the differences were not due to inhibitory deficits. Instead, a phase analysis localized differences to a transitional period of reversal learning. Females increased transitional errors that more likely indicated adaptive sampling strategies than memory failures. C57 females used this strategy indiscriminately, but DBA females sampled as a function of environmental uncertainty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Prereferral intervention programs represent a consultation-based approach for providing behavioral and/or instructional support to students before considering their eligibility for special class placement. Although research concerning the initial success of these programs has been promising, more information is needed relating program process variables to student outcomes in addition to effective procedures for promoting the adoption of these programs over time. This article describes organizational change procedures that were used to promote the acceptability of a prereferral intervention program at 4 pilot schools. Ss were school-based intervention team members (teachers, teaching assistants, school psychologists, and staff development facilitators) at each school. This article presents evaluation data concerning the program's acceptability to team members and participating teachers, integrity of the consultative process, and effect on numbers of children referred to special education. The implications of these results for school psychologists attempting to promote the acceptability and long-term adoption of prereferral intervention programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Membrane processing of used frying oils   总被引:2,自引:0,他引:2  
Studies were conducted with used frying oils in a flat membrane batch cell using five different types of polymeric membranes to decrease the soluble degradation products. During membrane processing, triglycerides permeated preferentially compared to the majority of the polar compounds including oxidation products, polymers, and color compounds. Two of the composite membranes, NTGS-AX and NTGS-2200, selectively rejected polar compounds and oxidation products to the extent of 25–48% and 24–44% respectively. The reduction in Lovibond color values (5R+Y) was in the range of 83–93%. The viscosity of the used frying oil was reduced to the extent of 22%. The composite membranes were effective in reducing the soluble impurities, as well as insoluble particulates, without causing any undesirable changes to the oil. The membrane process appears to improve the life of used frying oils and does not have the disadvantages associated with the active filtration systems, however, for commercial application the permeate flux needs to be improved considerably.  相似文献   
86.
Cadmium and zinc accumulation in soybean: A threat to food safety?   总被引:4,自引:0,他引:4  
A greenhouse study was conducted to quantify cadmium and zinc accumulated by soybean (Glycine max (L.) Merr.) when the metals were supplied separately and together. The highest dose of cadmium (100 mg/kg) reduced plant height and dry weight (down to 40% and 34% of control, respectively); the highest dose of zinc (2000 mg/kg) reduced plant height to 55% of control and dry weight to 70% of control. With both metals present, the plants were approximately the same size as those treated with cadmium only. The concentration of cadmium in the roots was unaffected by zinc. In other tissues, the effect of zinc on the accumulation of cadmium depended on the doses provided. At low doses, the addition of zinc reduced the concentration of cadmium in aboveground tissues to 40-50% of that found in plants exposed to cadmium only. However, when applied in high doses, the presence of zinc in cadmium-contaminated soils increased the uptake and accumulation of cadmium in aboveground tissues by up to 42%. In contrast, at high doses, the presence of cadmium in zinc-contaminated soil resulted in approximately 35% lower concentrations of zinc in all tissues. At a lower dose, cadmium had no effect on concentration of zinc in the plant tissues. The effects of high doses of one metal on the uptake of the other metal can be partially explained by the effects of one metal on the bioavailability of the other metal. In soils to which only one metal was added, bioavailable cadmium was 70-80% of the total cadmium, and bioavailable zinc was 50-70% of the total zinc. When both metals were added to the soil, 80-100% of the cadmium and 46-60% of the zinc were bioavailable. Concentrations of both metals were highest in root tissues (10-fold higher for cadmium, and up to 2-fold higher for zinc). Although relatively little cadmium was translocated to pods and seeds, the seeds of all plants (including those from control and zinc-treated plants) had concentrations of cadmium 3-4 times above the limit of 0.2 mg/kg set by the Codex Alimentarius Commission. This was surprising given that cadmium in the soil was only 1 mg/kg well below the maximum allowable amount for agricultural soil. While it is possible that more cadmium was accumulated by plants in this study than that which might occur under agricultural field conditions, these results reinforce the need to monitor concentrations of toxic metals in food crops.  相似文献   
87.
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma.  相似文献   
88.
Multicultural competence has become a mainstay within the training of professional psychologists, yet important areas within this framework remain to be more fully addressed. In particular, the dynamics of contemporary forms of racism have largely gone unexplored, depriving psychologists of clear direction in exploring the deepest levels of racist influences in their work. This qualitative analysis sought to shed light into this area by studying White people's experiences of race and racism. Although most affirmed the existence of racism, it was "spun" by most White participants--in other words, interpreted to their own advantage-into a problem that lies outside the scope of their own lives and responsibilities. Implications and resources for the practice and training of professional psychologists are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Reports an error in "Perceived social support among college students: Three studies of the psychometric characteristics and counseling uses of the Social Support Inventory" by Steven D. Brown, Theresa Brady, Robert W. Lent, Jenny Wolfert and Sheila Hall (Journal of Counseling Psychology, 1987[Jul], Vol 34[3], 337-354). In Table 5, the reliable change (RC) values for Clients 1-7 on the UCLA Loneliness Scale and the College Student Satisfaction Scale were incorrect. The corrected values are presented in the erratum. In addition, a note should be added to Table 5 that reads: "Posttreatment scores used in the calculation of RC are means obtained from the sum of posttreatment and follow-up scores." (The following abstract of the original article appeared in record 1987-32914-001.) Perceived social support has been shown to relate to psychological distress and well-being. However, measurement of the construct has been limited by a failure to embed perceived support in a body of psychological theory that would suggest how perceived support is produced and modified. In three studies we assessed the psychometric characteristics and counseling uses of a theory-derived measure of perceived social support, the Social Support Inventory (SSI). Results of the first study indicated that the SSI possessed excellent internal consistency reliability and concurrent validity, and it performed in theoretically predicted ways in a series of construct validity analyses. Results of the second study suggested that the SSI may not be influenced by mood state or demand characteristics. The third study concerned a counseling intervention developed from the SSI's theoretical base. Reported outcomes are from the first 7 consecutive college student clients exposed to the intervention for difficulties in their social transition to college. We also describe the person-environment fit theory from which the SSI was derived and discuss future conceptual and research needs on the theory, instrument, and intervention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
Videotaping of assessment center exercises has become an increasingly common practice, yet little is known about the impact of video technology on rating accuracy. This study compared ratings of a group discussion made after live observation (direct), after viewing a video (indirect), or after viewing a video with opportunities to pause and rewind (controlled). Results indicated some differences in observational accuracy but not in rating accuracy. Implications for the use of video technology in assessment centers are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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