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1.
Utilized D. D. Wickens's (1970) release from proactive interference (PI) task to assess automatic conceptual encoding at both the superordinate and subordinate category levels in 2 populations. Ss were 2nd and 4th graders from a low-socioeconomic-status Black community and 2nd and 4th graders from a middle-class White community. The principal factors in the study were list (superordinate: animals and foods; Subordinate 1: birds and mammals; Subordinate 2: fruits and vegetables), population, grade level, and condition (control vs shift) as between-Ss factors and trials (1–4) as a within-Ss factor. 48 children from each population and grade level served as Ss for each list. Results indicate significant PI build-up for all Grade?×?Population combinations on the 3 lists, with the exception of the 2nd graders on the superordinate list. Release from PI was observed at the 4th-grade level on the superordinate list and at both grade levels on Subordinate List 1 (birds and mammals). Generally speaking, reliable differences between the 2 populations in PI build-up and/or release were not detected. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
The Shedler-Westen Assessment Procedure-200 (SWAP) is a Q-sort instrument designed to assess personality pathology on the basis of clinician ratings. On the basis of research with the SWAP, its creators have proposed a group of 12 personality disorder (PD) diagnoses that can be used to replace or modify current Axis II categories of the Diagnostic and Statistical Manual of Mental Disorders (DSM). The authors discuss conceptual and empirical issues that require clarification before this proposal can be properly evaluated. They identify problematic psychometric features of the SWAP, including its unrepresentative normative sample, its reliance on a fixed skewed distribution, and anomalies in its T-score approach to diagnoses. In addition, a review of research on SWAP-based PD categories indicates that important information regarding diagnostic coverage, validity, and temporal stability is presently lacking. The authors conclude that research evidence is currently insufficient to justify the use of SWAP-based PD categories to guide revision of the DSM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
The aim of this study was to determine if mothers display identifiably different communicative styles in their interaction with their normally developing two- to five-year-old children. In order to investigate this issue an extensive coding system was developed, which assessed the structural organization and the communicative function of the speech of 71 mothers as they interacted with their children. By means of factor analysis three maternal communicative styles were distinguished: non-intervening, explaining and directing. In the non-intervening style there is no direct pressure from the mother on the child to respond verbally. The explaining mother is primarily concerned with providing information to her child in a way that gives the child little opportunity to take the speaking turn. The directing mother is mainly engaged in directing the child's behaviour by means of verbal control. The internal consistency of the three communicative styles appeared to be both satisfactory and related to relevant child and mother features.  相似文献   

4.
It is argued that goals are central to the meaning and structure of many traits and help define the prototypicality structure of those traits. Partly on the basis of L. W. Barsalou's (1985) work on goal-derived categories, it was predicted that goals help define the judged prototypicality of many trait-related behaviors and the confidence with which people make trait inferences from those behaviors. Consistent with this hypothesis, ratings of the extent to which behaviors achieved the goal associated with a trait strongly predicted the typicality of the behaviors. Furthermore, the rated goal-relatedness of a behavior also strongly predicted the confidence with which people would make a trait inference from that behavior. It is suggested that goals play a major role in the conceptual coherence of traits and other social categories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Previous research (e.g., S. A. Gelman & E. M. Markman, 1986; A. Gopnik & D. M. Sobel, 2000) suggests that children can use category labels to make inductive inferences about nonobvious causal properties of objects. However, such inductive generalizations can fail to predict objects' causal properties when (a) the property being projected varies within the category, (b) the category is arbitrary (e.g., things smaller than a bread box), or (c) the property being projected is due to an exogenous intervention rather than intrinsic to the object kind. In 4 studies, the authors showed that preschoolers (M = 48 months; range = 42-57 months) were sensitive to these constraints on induction and selectively engaged in exploration when evidence about objects' causal properties conflicted with inductive generalizations from the objects' kind to their causal powers. This suggests that the exploratory actions children generate in free play could support causal learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Examined speech samples from 6 children (aged 2 yrs to 2 yrs 5 mo), with mean lengths of utterance (MLUs) ranging from 2.93 to 4.14, for evidence of 6 syntactic categories: determiner, adjective, noun, noun phrase, preposition, and prepositional phrase. Results indicate that all the Ss showed evidence of all categories, except for the lowest MLU S, whose performance was borderline on adjectives and prepositional phrases. It is suggested that children are sensitive early in life to abstract, formal properties of the speech they hear and must be credited with syntactic knowledge at an earlier point than heretofore generally thought. Results argue against various semantic hypotheses about the origin of syntactic knowledge. It is concluded that the methods and results may be applicable to future investigations of why children's early utterances are short, the nature of children's semantic categories, and the nature of the deviance in the speech of language-deviant children and adults. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
Determined whether distribution of rewards by student supervisors in an industrial simulation was influenced by a situation in which a member of the work crew repeatedly disparaged their competence. Ss were 60 male undergraduates. Disparagement did not appear to affect the supervisor's allocation of rewards to an ingratiator, but it did result in a tendency to favor a compliant worker who was not an ingratiator. Under circumstances where he found himself the object of denigration by a subordinate, the supervisor gave the compliant worker higher creativity ratings on toy models designed during the simulation than he did in the control condition of the experiment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Four-year-olds' and adults' inferences based on shared conceptual properties, category labels, and perceptual information were assessed in 4 experiments. Stimuli included novel animals (Studies 1, 3, and 4) and familiar animals (Study 2). Experiments suggest that both category membership information and similarity (in the form of conceptual information and perceptually provided information) affect inferences. Furthermore, conceptual attribute information and category membership information were used differently by adults but not by children. It is concluded that the inferential behavior of children and adults is influenced by perceptual information, conceptual attribute information, and category membership information, as well as by hypotheses about how these kinds of information relate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
The tegument of bile-dwelling Fasciola gigantica is the interfacing layer that helps the parasite to maintain its homeostasis, and evade the hostile environment, including the host's immune attacks. The tegument is a syncytial layer about 10 mm thick, that is formed by the fusion of cytoplasmic processes of tegument cells, whose soma lie underneath the two muscle layers. The surface of the tegument is highly folded and invaginated into numerous ridges, pits and spines, which help to increase the surface area of the tegument for the absorption and exchanging of molecules, as well as for attachment. The outer membrane covering the tegument is a trilaminate sheet about 12 nm thick, and coated with a carbohydrate-rich glycocalyx layer that also bears high negative charges. Some host molecules may also be adsorbed onto this layer. These unique characteristics enable the parasite to evade the antibody-dependent cell-mediated cytotoxicity (ADCC) reaction exerted by the host. The outer membrane and glycocalyx is continuously replaced by the reserved membrane synthesized and stored in secretory granules of tegument cells, that are transported via cell processes towards the tegument by microtubules. The basal membrane of the tegument is trilaminate and invaginated to form membrane infoldings with closely aligned mitochondria. The tegument cytoskeleton is composed of a highly cross-linked network of 4-6 nm knobby microtrabecular fibers, bundles of intermediate filaments, microtubules that splay out from the tegument cells' processes. Major proteins of the cytoskeleton are actin, paramyosin and tubulin. The flukes' antigens that can elicit strong immunological responses in animal hosts are synthesized and released mainly from the tegument and the cecum. The majority of antigens derived from the surface membrane and the tegument are of MW 97, 66, 58, 54, 47 and 14 kDa, while those released from the cecum are cysteine proteases of MW 27, 26 kDa. Monoclonal antibodies have been raised against some of these antigens, and have been employed in immunodiagnosis of the infection. From the protection conferred to animal models and the in vitro killing assays of young parasites by specific antibodies, candidate vaccines could be selected from these antigens, such as, an antioxidant enzyme, glutathione-S-transferase, the digestive enzyme cysteine proteases, the surface-tegument proteins, such as fatty acid binding protein (14 kDa), membrane proteins (at 66 kDa), as well as muscle protein paramyosin, and hemoprotein. Ongoing research have been directed at deciphering the genetic codes and the syntheses of some of these antigens by recombinant DNA technology.  相似文献   

12.
OBJECTIVE: To determine the relation between the initial neonatal nucleated erythrocyte (nRBC) count and acute infection or ischemia in cases delivered before 32 weeks' gestation. METHODS: A set of 465 nonanomalous singleton live births delivered at 22-32 weeks' gestational age (GA) contained 386 cases with a complete blood count obtained by 3 hours of life, including 173 cases of premature rupture of the membranes (PROM) before labor, 143 cases of preterm labor with intact membranes (PTL), and 70 cases of preeclampsia. Maternal and neonatal charts were reviewed. Placental histopathology was scored in the following five categories: acute intrauterine inflammation, uteroplacental vascular lesions, intraplacental vaso-occlusive lesions, chronic inflammation, and coagulation-related lesions. The initial nRBC count (nRBCs/100 white blood cells [WBC] x WBC count/dL) was analyzed. RESULTS: In PROM and PTL (controlling for GA), the nRBC count was directly related to the maternal WBC count (PTLP = .018), maternal temperature within 24 hours of delivery (PROM P = .014), initial neonatal WBC count (PROM P < .0001; PTL P = .0004), total myeloid elements (PROM P = .005, PTL P = .009), total nonmyeloid elements (PROM P < .0004, PTL P < .0001), and total placental acute inflammatory score (PROM P = .04, PTL P = .02). In preeclampsia, cytotrophoblast proliferation (P = .02), villous edema (P = .008), "hemorrhagic endovasculitis" (P = .04), and histologic abruption (P = .0006) were directly related to the nRBC count. In well-grown, nonacidotic, nondepressed preterm infants, the nRBC count was independent of gestational age, with the 90th percentile at 5229 nRBC/dL. CONCLUSION: When preterm PROM and PTL are accompanied by acute ascending infection, nRBC release may be a fetal response to the inflamed environment. In preterm preeclampsia, nRBC elevation marks uteroplacental hypoperfusion.  相似文献   

13.
Two experiments on the process of rule discovery in groups were conducted using a card deck and Wason number triple tasks. The positive effects of incentives on the proportion of correct hypotheses could not be explained by differential testing. The variables "hypothesis vs. target testing" and "small vs. broad range of rule" did not affect this proportion. There was a preponderance of positive tests, declining during trials. Negative tests occurred more often under the target test and broad rule range conditions. The positivity heuristic diminished in importance during trials, whereas the sufficiency, necessity, and Klayman and Ha heuristics increased. Groups produced fewer false and more correct results than individuals. According to the probabilistic model of opinion change, plausibility and faction size contributed to the group process differentially, depending on the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Curriculum-based assessment assesses the match between curriculum and student skill by computing the percentage of known words in a reading task and comparing it to the instructional level criterion of 93% to 97% known. The current study examined the effect of preteaching unknown words to 29 third-grade children identified as learning disabled (LD) to facilitate an instructional level within a third-grade curriculum. Second, the study examined the potential implications for implementing response-to-intervention. Results suggested that children within the treatment condition were more likely to read at the instructional level and demonstrated progress within a local curriculum that significantly exceeded a control group who received guided reading activities. The correlation between number of passages read at the instructional level and reading progress within the curriculum was .80. Finally, 65.5% of the children who received the treatment were identified as responding to treatment, as compared to 27.6% of the control group. Potential implications for practice and suggestions for future research are included. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Polyclonal antibodies were used to localize structural cell-wall proteins in differentiating protoxylem elements in etiolated bean and soybean hypocotyls at the light- and electron-microscopic level. A proline-rich protein was localized in the lignified secondary walls, but not in the primary walls of protoxylem elements, which remain unlignified, as shown with lignin-specific antibodies. Secretion of the proline-rich protein was observed during lignification in different cell types. A glycine-rich protein (GRP1.8) was specifically localized in the modified primary walls of mature protoxylem elements and in cell corners between xylem elements and xylem parenchyma cells. The protein was secreted by Golgi bodies both in protoxylem cells after the lignification of their secondary walls and in the surrounding xylem parenchyma cells. The modified primary walls of protoxylem elements were visualized under the light microscope as filaments or sheets staining distinctly with the protein stain Coomassie blue. Electron micrographs of these walls show that they are composed of an amorphous material of moderate electron-density and of polysaccharide microfibrils. These materials form a three-dimensional network, interconnecting the ring- or spiral-shaped secondary wall thickenings of protoxylem elements and xylem parenchyma cells. The results demonstrate that the modified primary walls of protoxylem cells are not simply breakdown products due to partial hydrolysis and passive elongation, as believed until now. Extensive repair processes produces cell walls with unique staining properties. It is concluded that these walls are unusually rich in protein and therefore have special chemical and physical properties.  相似文献   

16.
Although functional links between emotion and action are implied in emotion regulation research, there is limited evidence that specific adaptive actions for coping with a challenge are more probable when certain negative emotions are expressed. The current study examined this question among 3- and 4-year-olds (N = 113; M age = 47.84 months, SD = 6.19). Emotion expressions and actions were observed during 2 challenging tasks: children waited for a gift while the mother worked, and children worked alone to retrieve a prize from a locked box with the wrong key. Angry and happy expressions, compared with sad expressions, were associated with more actions. These actions varied with the nature of the task, reflecting appreciation of situational appropriateness. In addition, when waiting with the mother, happiness was associated with the broadest range of actions, whereas when working alone on the locked box, anger was associated with the broadest range of actions. Results are discussed in terms of the adaptive function of negative emotions and in terms of functional and dimensional models of emotion. Findings have implications for the development of emotion regulation and social–emotional competence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Three experiments investigated the ability of 3-, 5-, and 8-year-old children as well as adults to learn sets of perceptual categories. Adults and children performed comparably on categories that could be learned by either a single-dimensional rule or by associative learning mechanisms. However, children showed poorer performance relative to adults in learning categories defined by a disjunctive rule and categories that were nonlinearly separable. Increasing the task demands for adults resulted in child-like performance on the disjunctive categories. Decreasing the task demands for children resulted in more adult-like performance on the disjunctive categories. The authors interpret these results within a multiple-systems approach to category learning and suggest that children have not fully developed the same explicit category learning system as adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Reports results of an investigation of 2nd, 4th, and 6th graders under either game or test conditions. Several implications of attentional theories of test anxiety are reported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
People attempting to generate random sequences usually produce more alternations than expected by chance. They also judge overalternating sequences as maximally random. In this article, the authors review findings, implications, and explanatory mechanisms concerning subjective randomness. The authors next present the general approach of the mathematical theory of complexity, which identifies the length of the shortest program for reproducing a sequence with its degree of randomness. They describe 3 experiments, based on mean group responses, indicating that the perceived randomness of a sequence is better predicted by various measures of its encoding difficulty than by its objective randomness. These results seem to imply that in accordance with the complexity view, judging the extent of a sequence's randomness is based on an attempt to mentally encode it. The experience of randomness may result when this attempt fails. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

20.
Human seminal plasma sperm motility inhibitor (SPMI) proteins which are exclusively secreted from seminal vesicles, inhibit sperm motility. It is secreted as biologically active 52 kDa and a mixture of 71 and 76 kDa precursor forms, which are identical to semenogelin-I and II (Sg-I and Sg-II), respectively. To understand the molecular mechanism underlying the inhibition of sperm motility by SPMI proteins, we expressed human Sg-I and Sg-II genes in insect cells using a baculovirus system. The baculoviruses expressing full-size Sg-I and Sg-II proteins that were N-terminally-tagged with a hexahistidine were selected, and were infected with Sf 21 cells. The Sg-I and Sg-II proteins were purified from infected cells by column chromatography using Ni-NTA resin 48 h after infection. The full-size Sg-I and Sg-II proteins were obtained in soluble forms. However, they tended to aggregate to form a gel, as expected from naturally occurring semenogelin. Both the purified recombinant Sg-I and Sg-II proteins showed strong SPMI activities with a complete inhibition of sperm motility at 60 units/mg, equivalent to the natural proteins. This production system that permits the generation of purified Sg-I and Sg-II proteins, as well as mutant derivatives, will be helpful for further study on male infertility.  相似文献   

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