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11.
Jaakkola Kelly; Fellner Wendi; Erb Linda; Rodriguez Mandy; Guarino Emily 《Canadian Metallurgical Quarterly》2005,119(3):296
In 2 experiments, bottlenose dolphins (Tursiops truncatus) judged the ordinal relationship between novel numerosities. The dolphins were first trained to choose the exemplar with the fewer number of items when presented with just a few specific comparisons (e.g., 2 vs. 6, 1 vs. 3, and 3 vs. 7). Generalization of this rule was then tested by presenting the dolphins with all possible pairwise comparisons between 1 and 8. The dolphins chose the exemplar with the fewer number of items at levels far above chance, showing that they could recognize and represent numerosities on an ordinal scale. Their pattern of errors was consistent with the idea of an underlying analog magnitude representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Gregory S. Ho Chen Huang Emily A. Carter 《Current Opinion in Solid State & Materials Science》2007,11(5-6):57-61
Orbital-free density functional theory (OF-DFT) can be made to scale linearly with sample size, allowing thousands of atoms to be treated explicitly with quantum mechanics. State-of-the-art kinetic energy density functionals and ion–electron pseudopotentials are used to obtain accurate structural property predictions for nanoparticles, nanowires, extended surfaces, and nanoindentation of simple metals. 相似文献
13.
The isoparametric spline finite strip method has been applied to the free vibration and stability analysis of shells. The convergence of the method is reviewed critically. Additional numerical examples on shells of different geometry are also employed to demonstrate the efficiency, accuracy and versatility of the method. 相似文献
14.
The object of this paper is to demonstrate the usefulness of the transalkylation reaction for determining chemical structural features of products derived from coal. For example, the method is applied to derivatized coals, coals modified by thermolysis, and materials physically or chemically separated from coals. Data are presented for the pyridine soluble and insoluble parts of two coals, an O-methylated coal, a Birch reduced coal, a solvent refined coal, and a coke. Similarities and differences in chemical make-up of these materials are discussed. 相似文献
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Takes issue with the biological focus of traditional theories of sexuality, drawing on postmodern trends such as hermeneutics and social constructionism. It is argued that traditional theories are characterized by a reductionism that precludes meaningfulness and an individualism that precludes genuine intimacy. The theories thus offer an essentially barren account of what is otherwise a richly meaningful human activity. A more fruitful account of human sexuality begins with acknowledging that sexuality is a fundamentally social and meaningful phenomenon and that it can only be understood in the social, historical, and moral context in which human beings live and act. If the linguistic aspect of sexuality were at the heart of theories, biological information could be given its proper place as context for understanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
Chronic lymph drainage techniques in sheep have been used to map the pathways and to quantify the fluid and cell traffic through periodontal tissues. The continuous collection of cervical and prescapular lymph has demonstrated that 65% of labelled protein tracer injected into the periodontal tissues could be found in lymph over a period of 7.5 hours. Nearly 90% of the total radioactivity could be accounted for between the lymph and the tissue site. When silk was impregnated with radiolabelled albumin and a tooth ligated, the kinetics of the subsequent appearance of the tracer in lymph emphasized the ease with which macromolecules surrounding the teeth gain access to the lymphatics, regional lymph nodes, and immune apparatus. Animals were primed with BCG and then tuberculin (delayed hypersensitivity) lesions were simultaneously induced in the skin, bowel, and periodontium. When T cells were labelled with radioisotopes and their migration from blood to lymph measured, the periodontal tissue traffic pattern was distinct from the traffic pattern through DTH in the skin and also distinct from the pattern through the small intestine. This indicates that the lymphocyte traffic through the inflamed periodontium has unique features. This tissue specificity was not apparent when lesions were induced with TNFalpha. The static assessment of lymphocyte subsets within the tissues was also assessed with immunohistochemistry. 相似文献
18.
Finer lamellar spacing in the lamellar structure of a Ti–45Al–2Nb–2Mn + 0.8 vol.%TiB2 (45XD) alloy does improve the primary creep resistance. However, the unstable nature of the fine plate contributes largely to the degradation of the lamellar structure and a rapid increase in the tertiary creep rate, indicating that a fine lamellar structure has a detrimental effect on the long-term creep. 相似文献
19.
Methane was pulsed over pure CuO and NiO as well as Cu/La2O3 and Ni/La2O3 catalysts at 600° C. Results indicate that the mechanisms for methane activation over copper and nickel are quite different. Over CuO, methane is converted to CO2 and H2O, most likely via the combustion mechanism; whereas metallic copper does not activate methane. Over NiO in the presence of metallic nickel sites, methane activation follows the pyrolysis mechanism to give CO, CO2, H2 and H2O. Similar results were obtained over the Cu/La2O3 and Ni/La2O3 catalysts. XRD investigations indicate that copper and nickel existed as CuLa2O4 and LaNiO3 respectively in the La2O3-supported catalysts. The effect of La2O3 on the activation of methane is discussed. 相似文献
20.