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101.
Reviews the books, Human Laterality (1983) and The Ambivalent Mind (1983)by Michael C. Corballis. These two books explore human cerebral lateralization and handedness, their relationship to each other, and the relationship of both to aspects of cognitive performance. Human Later ality is the better of the two books for the researcher or the professional interested in these topics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
DA Brake G Strang JE Lineberger CH Fedor R Clare TA Banas T Miller 《Canadian Metallurgical Quarterly》1997,76(7):974-983
The immunogenicity of a tissue culture-derived vaccine generated from an Eimeria tenella-infected cell line in a serologically defined bird line, and the ability to confer protection against homologous challenge in young chicks was examined. The cell line, SB-CEV-1/F7, was infected with E. tenella sporozoites and the resulting 72-h postinfection cell-free supernatants were adjuvanted and used to immunize Leghorn chicks homozygous for the B19 haplotype. Peripheral blood and splenic lymphocytes from these immunized birds proliferated in vitro in response to both sporozoite and SB-CEV-1/F7 tissue culture-derived parasite antigens. In addition, splenic immune lymphocytes obtained from birds previously exposed to E. tenella in vivo responded to these tissue culture-derived parasite antigens in vitro. To evaluate the efficacy of the vaccine, B19B19 chicks were vaccinated s.c. with adjuvanted 72-h postinfection cell-free supernatants or an ammonium sulfate precipitate derivative thereof, orally boosted, and then subjected to homologous parasite challenge at 10 d of age. The level of protection (body weight gain, cecal lesions) was assessed 6 d after challenge. Performance results from four battery trials demonstrated that vaccinated birds were significantly protected against weight loss compared to unimmunized, challenged controls. In addition, in two of the four trials, vaccinated birds were significantly protected against lesions. These results provide strong evidence that tissue culture-derived parasite antigens obtained from the E. tenella-infected SB-CEV-1/F7 cell line are immunogenic in birds and can provide partial protection against E. tenella clinical coccidiosis. 相似文献
103.
Solutions of Cu(II) and Fe(II) establish the redox equilibrium which is displaced to the right by addition of either Cl? or acetonitrile (AN). Log K varies from ?10.5 in water to about ?2.5 in 4 M NaCl or AN, allowing iron to be removed selectively from copper (II) solutions either by solvent extraction with Versatic acid or by precipitation as goethite or j jarosite. To establish the required conditions Eh-pH diagrams have been developed for the CuH2OCl and CuH2OANSO42-systems at 25°C and 90°C. It is demonstrated that the catalytic effect of Cu(II) on the oxidation of Fe(II) to Fe(III) by O2 is dependent on the concentration of Cl? or AN and on the position of this redox equilibrium. Applications to removing iron from hydrometallurgical solutions are discussed and tested. 相似文献
104.
We review information on the structure of proline-rich proteins (PRPs), their various functions related to oral homeostasis and dietary tannin, and the structural basis of these functions. Consideration of the multifunctional nature of these salivary proteins helps explain both the subtle and large variations found in structure and secretion rates both within individuals and between species. We propose that the ancestral function of PRPs is in maintaining oral homeostasis and that counteracting dietary tannins by binding with them is a derived function. PRPs are effective in oral homeostasis at low secretion levels, whereas counteracting tannin depends on high secretion levels. In the dietary habits ranging from carnivores through omnivores to exclusively planteaters, the dietary nitrogen level is progressively reduced, and plant allelochemical intake, including tannins, increases. We suggest that during this evolution from meat-eater to plant-eater, there was some point in omnivory at which selective pressure from nitrogen limitations, arising from a low nitrogen/high tannin diet, became sufficiently great for the evolution of increased secretion level and diversification of PRPs for dealing with tannin. If this hypothesis is correct, carnivorous mammals should secrete low levels of PRPs for oral homeostasis, but should never secrete high levels, unless they are secondarily carnivorous. Omnivores consuming a diet of very little animal tissue but higher levels of tannin-containing foliage or fruit should generally have the capacity to produce high levels of salivary PRPs. Browsers and frugivores should also produce high levels of PRPs, but grazers may have reduced secretion rates depending on the antiquity of the dietary habit. This hypothesis is consistent with the limited information available on the abundance, type, and distribution of PRPs in mammals. Studies are suggested which would test the functional and evolutionary arguments presented. 相似文献
105.
Clare M. Rimnac Timothy M. Wright Robert W. Klein 《Polymer Engineering and Science》1988,28(24):1586-1589
Fracture of ultra high molecular weight polyethylene (UHMWPE) contributes to damage modes occurring on the articulating surfaces of total joint replacement components. To minimize damage through the optimization of component design requires an understanding of the fracture behavior of UHMWPE. A fracture/mechanics approach was taken in which J integral tests were performed on three-point bend specimens of two thicknesses. JIC was determined to be 99.5 kJ/m2 and was independent of specimen thickness. The fracture surfaces for both specimen thicknesses showed extensive orientation and failure through multiple layers of material, suggesting that UHMWPE experiences plane stress conditions at the crack tip, regardless of thickness. 相似文献
106.
107.
Yoshiyuki Kubota Mary Clare Sison Escao Hiroshi Nakanishi Hideaki Kasai 《Journal of Alloys and Compounds》2008,458(1-2):151-157
Silicon is of special interest in lithium-ion batteries (LIBs) since it has large theoretical specific capacity or volumetric capacity. The crystal structure, charge distribution and density of states of LiSi as the Li-poorest side compound at the start of Li intercalation mechanism for Si anode in LIBs has been studied by using density functional theory (DFT) calculations. The triangular pyramids are formed by four Li atoms in LiSi. Compared to the charge density of crystalline Si, the SiSi covalent bonds in LiSi become weak due to Li intercalation. On the other hand, the electrons around the Li atoms in LiSi increase compared to those in metallic Li. The Li atoms in LiSi have negative charge of 0.83–0.84. These electrons, which are transferred from p electrons in the Si atoms, are mainly made of p electrons of the Li atoms. When considering the lithium intercalation reaction from crystalline Si to LiSi, the average intercalation voltage is about 0.4 V. 相似文献
108.
Mark S. Rybchyn Tara Clare Brennan-Speranza David Mor Zhiqiang Cheng Wenhan Chang Arthur D. Conigrave Rebecca S. Mason 《International journal of molecular sciences》2021,22(12)
We recently found that, in human osteoblasts, Homer1 complexes to Calcium-sensing receptor (CaSR) and mediates AKT initiation via mechanistic target of rapamycin complex (mTOR) complex 2 (mTORC2) leading to beneficial effects in osteoblasts including β-catenin stabilization and mTOR complex 1 (mTORC1) activation. Herein we further investigated the relationship between Homer1 and CaSR and demonstrate a link between the protein levels of CaSR and Homer1 in human osteoblasts in primary culture. Thus, when siRNA was used to suppress the CaSR, we observed upregulated Homer1 levels, and when siRNA was used to suppress Homer1 we observed downregulated CaSR protein levels using immunofluorescence staining of cultured osteoblasts as well as Western blot analyses of cell protein extracts. This finding was confirmed in vivo as the bone cells from osteoblast specific CaSR−/− mice showed increased Homer1 expression compared to wild-type (wt). CaSR and Homer1 protein were both expressed in osteocytes embedded in the long bones of wt mice, and immunofluorescent studies of these cells revealed that Homer1 protein sub-cellular localization was markedly altered in the osteocytes of CaSR−/− mice compared to wt. The study identifies additional roles for Homer1 in the control of the protein level and subcellular localization of CaSR in cells of the osteoblast lineage, in addition to its established role of mTORC2 activation downstream of the receptor. 相似文献
109.
Peter T. Cummings Clare McCabe Christopher R. Iacovella Akos Ledeczi Eric Jankowski Arthi Jayaraman Jeremy C. Palmer Edward J. Maginn Sharon C. Glotzer Joshua A. Anderson J. Ilja Siepmann Jeffrey Potoff Ray A. Matsumoto Justin B. Gilmer Ryan S. DeFever Ramanish Singh Brad Crawford 《American Institute of Chemical Engineers》2021,67(3):e17206
110.
The Gibbs free energy of solvation (ΔGsolv) for C60, and six other idealized, non-functionalized, fullerene particles of differing size and shape has been determined in octanol and water solvents from molecular dynamics simulations using thermodynamic integration. In particular, we have studied Buckminster fullerene (C60) and open and capped carbon nanotubes of different aspect ratios and solvent accessible surface areas. Knowledge of the ΔGsolv of a molecule in octanol and water can be used to understand the partitioning of the molecule between organic and aqueous phases and is one of several parameters used to model the fate of chemicals in the natural environment. The simulations were performed at ambient conditions, i.e., a temperature of 25 °C and a pressure of 1 bar. The fullerene molecules are all found to have a very high ΔGsolv in water, and a very low ΔGsolv in octanol, suggesting a strong preference for the organic phase. From a comparison of the results for capped and uncapped carbon nanotubes we found that the uncapped tubes exhibit significantly higher ΔGsolv than capped tubes. Furthermore, for capped carbon nanotubes, hydrophobic/organophilic shifts are observed with increasing excluded volume and solvent accessible surface area. 相似文献