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121.
Two experiments investigated children's implicit and explicit differentiation between beliefs about matters of fact and matters of opinion. In Experiment 1, 8- to 9-year-olds' (n = 88) explicit understanding of the subjectivity of opinions was found to be limited, but their conformity to others' judgments on a matter of opinion was considerably lower than their conformity to others' views regarding an ambiguous fact. In Experiment 2, children aged 6, 8, or 10 years (n = 81) were asked to make judgments either about ambiguous matters of fact or about matters of opinion and then heard an opposing judgment from an expert. All age groups conformed to the opposing judgments on factual matters more than they did to the experts' views on matters of opinion. However, only the oldest children explicitly recognized that opinions are subjective and cannot be "wrong." Implications of these results for models of children's reasoning about epistemic states are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
Accurate predictions of future reconviction, including those for violent crimes, have been shown to be greatly aided by the use of formal risk assessment instruments. However, it is unclear as to whether these instruments would also be predictive in a sample of offenders with intellectual disabilities. In this study, the authors have shown that the Violence Risk Appraisal Guide (V. L. Quinsey, G. T. Harris, M. E. Rice, & C. Cormier, 1998); the Psychopathy Checklist--Screening Version (S. D. Hart, D. N. Cox, & R. D. Hare, 1995); and the History, Clinical, Risk Management--20 (C. D. Webster, K. S. Douglas, D. Eaves, & S. D. Hart, 1997) were all significant predictors of violent and general reconviction in this sample, and in many cases, their efficacy was greater than in a control sample of mentally disordered offenders without an intellectual disability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
In this study, the potential and feasibility of the use of panchromatic and multispectral QuickBird data for the identification and spatial characterization of archaeological sites was evaluated. The analysis focused on an assessment of the capability of QuickBird images to detect surface anomalies expected in the presence of archaeological buried remains. The investigations were performed for a test case in the south of Italy, where human activity has been logged from the Palaeolithic to the Middle Ages. The results show that the QuickBird panchromatic and data fusion products can be a flexible data source for archaeological prospection, and can be useful for extracting features of archaeological sites prior to any excavation work and for increasing the cultural value of historical sites.  相似文献   
124.
In this article, the task of remote-sensing image classification is tackled with local maximal margin approaches. First, we introduce a set of local kernel-based classifiers that alleviate the computational limitations of local support vector machines (SVMs), maintaining at the same time high classification accuracies. Such methods rely on the following idea: (a) during training, build a set of local models covering the considered data and (b) during prediction, choose the most appropriate local model for each sample to evaluate. Additionally, we present a family of operators on kernels aiming to integrate the local information into existing (input) kernels in order to obtain a quasi-local (QL) kernel. To compare the performances achieved by the different local approaches, an experimental analysis was conducted on three distinct remote-sensing data sets. The obtained results show that interesting performances can be achieved in terms of both classification accuracy and computational cost.  相似文献   
125.
BACKGROUND: Interleukin-3, a recombinant cytokine with multilineage stimulatory effect on hematopoietic cells, was administered to 22 previously untreated breast cancer patients following high-dose therapy with cyclophosphamide (7 g/m2). PATIENTS AND METHODS: The growth factor, administered through continuous intravenous infusion at 1 (3 patients), 2.5 (3 patients), 5 (10 patients) and 10 micrograms/kg/day (6 patients), was well tolerated up to 5 micrograms/kg/day. RESULTS: Nausea, vomiting, fever and headache prevented administration of the intended dose to all 6 patients in the 10 micrograms/kg/day cohort. At the maximal tolerable dose (5 micrograms/kg/day) the growth factor significantly accelerated granulocyte, platelet and reticulocyte recovery as compared to matched historical controls who received high-dose cyclophosphamide without cytokine infusion. Moreover, no platelet transfusions and fewer erythrocyte transfusions were required in interleukin 3-treated patients. In contrast to GM-CSF and G-CSF, interleukin 3 showed no effect on the mobilization of hematopoietic progenitor cells in the peripheral blood. CONCLUSIONS: Interleukin-3 represents a well-tolerated cytokine, clinically useful for accelerating trilineage hematopoietic recovery following severely myelotoxic treatments such as high-dose cyclophosphamide.  相似文献   
126.
The pathogenesis of acquired pulmonary alveolar proteinosis (PAP), a rare lung disease characterized by excessive surfactant accumulation within the alveolar space, remains obscure. Gene-targeted mice lacking the hematopoietic growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF) or the signal-transducing beta-common chain of the GM-CSF receptor have impaired surfactant clearance and pulmonary pathology resembling human PAP. We therefore investigated the hematopoietic effects of GM-CSF in patients with PAP. The hematologic response of 5 infants with congenital PAP to 5 microgram/kg/d was of normal magnitude. By contrast, despite normal expression of GM-CSF receptor alpha- and beta-common chains on peripheral blood myelomonocytic cells (n = 6) and normal binding affinity of bone marrow mononuclear cells for GM-CSF (n = 3), each of the 12 patients with acquired PAP treated displayed impaired responses to GM-CSF; 5 microgram/kg/d produced only minor eosinophilia, and doses of 7.5 to 20 microgram/kg were required to induce >/=1.5-fold neutrophil increments in the 3 patients who underwent dose-escalation. However, neutrophilic responses to 5 microgram/kg granulocyte colony-stimulating factor (G-CSF) were normal (n = 4). In vitro, the proportion of hematopoietic progenitors responsive to GM-CSF (16.1% +/- 8.9%; P = .042) or interleukin-3 (IL-3; 19.3% +/- 7.7%; P = .063), both of which utilize the beta-common chain of the GM-CSF receptor complex, were reduced among patients with acquired PAP (n = 4) compared with normal bone marrow donor controls (47.2% +/- 25.9% and 40.9% +/- 18.6%, respectively). In the one individual who had complete resolution of lung disease during the period of study, this was temporally associated with correction of this defective in vitro response to GM-CSF and IL-3 on serial assessment. These data establish that patients with acquired PAP have an associated impaired responsiveness to GM-CSF that is potentially pathogenic in the development of their lung disease. Based on these observations, we propose a model of the pathogenesis of acquired PAP that suggests the disease arises as a consequence of an acquired clonal disorder within the hematopoietic progenitor cell compartment.  相似文献   
127.
We reflect on the methods, activities and perspectives we used to situate digital storytelling in two rural African communities in South Africa and Kenya. We demonstrate how in-depth ethnography in a village in the Eastern Cape of South Africa and a design workshop involving participants from that village allowed us to design a prototype mobile digital storytelling system suited to the needs of rural, oral users. By leveraging our prototype as a probe and observing villagers using it in two villages in South Africa and Kenya, we uncovered implications for situating digital storytelling within those communities. Finally, we distil observations relevant to localizing storytelling and their implications for transferring design into a different community.  相似文献   
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A new family of 9,9-bisalkylfluorene (F)/thiophene (T)/benzothiadiazole (B) π-conjugated copolymers for organic solar cells is reported. The structure of the reported copolymers is pseudorandom: in turn each F, T, B monomer unit is alternated to the other randomly distributed two units. Voltammetric, UV–visible, and photoluminescence measurements have been carried out to assess the optical and electronic properties of the synthesized materials. The occurring of photoinduced charge transfer towards a fullerene electron acceptor was investigated by photoluminescence quenching and light-induced electron spin resonance experiments. The copolymer having alternating thiophene monomer units and randomly distributed fluorene and benzothiadiazole units exhibits the most promising characteristics; the photophysic study shows that such polymer/fullerene blend could represent a novel and cheaper material to be used as convenient donor–acceptor system for polymer solar cells.  相似文献   
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