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排序方式: 共有542条查询结果,搜索用时 15 毫秒
61.
Kevin Coe David Domke Erica S. Graham Sue Lockett John Victor W. Pickard 《The Journal of communication》2004,54(2):234-252
Binary communications represent the world as a place of polar opposites. Such conceptions of reality, although not uncommon in Western thought, take on a heightened importance when political leaders employ them in a concerted, strategic discourse in a mass media environment. With this in mind, this research offers a conception of binary discourse and uses this as a foundation to examine (a) the use of binaries by U.S. President George W. Bush in 15 national addresses, from his inauguration in January 2001 to commencement of the Iraq War in March 2003, and (b) the responses of editorials in 20 leading U.S. newspapers to the president's communications. 相似文献
62.
对于终端厂商而言,亚太区是全球最大的市场,并且潜力最大,因为这一地区拥有全球40%的移动用户。随着欧洲和北美等成熟市场增长趋缓,亚太区的重要性正日渐提升。在那些收入存在较大差距的地区,现阶段运营商面临的挑战是既要鼓励高端用户使用数据业务,又要吸引低收入人群入网而对于设备商而言,则必须在保持现有利润水平的前提下为运营商和消费者提供丰富多彩的终端。无论是运营商、终端提供商还是应用开发商在制定战略时都必须对未来的终端技术有一个清楚的认识。与西欧所有运营商只采用GSM和WCDMA不同的是,亚太地区正在或计划使用的技术… 相似文献
63.
Songfeng Guo Garrett G Grindle Erica L Authier Rory A Cooper Shirley G Fitzgerald Annmarie Kelleher Rosemarie Cooper 《IEEE transactions on neural systems and rehabilitation engineering》2006,14(1):83-90
Increased physical activity is important for reducing the risk of cardiovascular disease. However, among people with disabilities, inactivity is prevalent. In order to encourage exercise among members of this group, an exercise system combining arm ergometry with video gaming, called the GAME(Cycle) was previously developed. User input was received through an arm crank ergometer on a swivel, with the angular velocity of the ergometer resistance wheel controlling one axis and rotation of ergometer about the swivel controlling the other. The purpose of this study was to detail the algorithms used in this device and present novel features included in a second generation of the GAME(Cycle). The features include a wheel on base, a steering return mechanism, and wireless fire buttons. A focus group of clinicians (n = 8), wheelchair users (n = 8), and clinician wheelchair users (n = 2) was conducted to evaluate the features of the GAME(Cycle). The focus group suggested improvements to the steering mechanism and to reduce vibration in the system. However, the focus group enjoyed the GAME(Cycle) and felt that it would encourage exercise among persons with disabilities. 相似文献
64.
Preecha Panya Erica J. Wanless Orn-anong Arquero George V. Franks 《Journal of the American Ceramic Society》2005,88(3):540-546
The rheological behavior of ceramic glaze suspensions containing limestone, quartz, feldspar, and kaolin, has been improved by the addition of either a cationic (cetylpyridinium chloride, CPC) or an anionic (sodium dodecylbenzenesulfonate, SDBS) surfactant. Additional stability and lower viscosity can result from either electrical double layer repulsion or steric repulsion depending on the surfactant type, concentration, ionic strength, and pH. Underdosing may result in high viscosity due to charge neutrality and hydrophobic attraction between particles while overdosing may result in high viscosity possibly due to micelles in the solution. The situation is particularly complicated for glazes containing limestone and anionic surfactant at moderate to low pH where calcium carbonate is soluble. The anionic surfactant and calcium ions can form complexes that are poorly soluble and strongly adsorb to the surface of the particles. The resulting thick steric layer of complexes produces a significant repulsion and stable, low viscosity suspensions. ζ potential measurements and adsorption isotherms are used to interpret the rheological behavior. 相似文献
65.
Finn Peter R.; Sharkansky Erica J.; Viken Richard; West Tara L.; Sandy Jamie; Bufferd Gary M. 《Canadian Metallurgical Quarterly》1997,106(1):26
In 2 samples of sons of alcoholics (family history positive for alcoholism; FHP: N?=?74 & N?=?72), cluster analyses identified 3 subtypes of familial vulnerability: 1 with low levels of familial psychopathology (FHP-LP) and moderate levels of familial alcoholism; a 2nd with high levels of familial antisocial personality (FHP-ASP), violence, and alcoholism; and a 3rd with high levels of familial depression (FHP-DEP), mania, anxiety disorder, and alcoholism. Compared with family history negative (FHN) participants (N?=?106), FHP offspring had higher levels of alcohol problems. FHP-ASP offspring had elevated levels of antisocial traits and negative affect. Compared with FHN participants, FHP-DEP offspring elevated levels of antisocial traits, hypomania, and experience seeking. FHP-LP offspring had moderate levels of antisocial traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Rosenfeld Erica; Huesmann L. Rowell; Eron Leonard D.; Torney-Purta Judith V. 《Canadian Metallurgical Quarterly》1982,42(2):347
Developed the Children's Fantasy Inventory using 748 1st and 3rd graders. Within the limits of a 45-item instrument relevant to the children's attention span, a wide range of fantasy activity was tapped. The 9 empirically derived, nonorthogonal scales had good internal consistency, as measured by coefficient alpha, and good test–retest reliabilities. The scales on the Children's Fantasy Inventory were related to other previously used measures of fantasy in children and to previously derived adult scales. Differences in styles of fantasy were found between boys and girls and between 1st and 3rd graders, but there were no significant differences in overall frequency of fantasy. Retesting after a year's lag indicated that fantasy behaviors had significant stability over time. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Ziegler KJ Schmidt DJ Rauwald U Shah KN Flor EL Hauge RH Smalley RE 《Nano letters》2005,5(12):2355-2359
A two-phase liquid-liquid extraction process is presented which is capable of extracting water-soluble single-walled carbon nanotubes into an organic phase. The extraction utilizes electrostatic interactions between a common phase transfer agent and the sidewall functional groups on the nanotubes. Large length-dependent van der Waals forces for nanotubes allow the ability to control the length of nanotubes extracted into the organic phase as demonstrated by atomic force microscopy. 相似文献
68.
Conducted 3 experiments with 256 7–10 yr olds in which Ss were induced to donate some of their winnings from a game to poor children. They were then praised for their behavior (reinforcement), told they must have donated because they were helpful people (attribution), or told nothing (control). Subsequent donation, and behavior on a variety of tests of generalized altruism, was assessed. The donation of all Ss was increased both by reinforcement and attributions of prosocial behavior. Neither reinforcement nor attribution affected the generalized altruism of 5-yr-olds, only attribution affected the generalized altruism of 8-yr-olds, and both reinforcement and attribution affected the generalized altruism of 10-yr-olds. Findings are discussed in terms of the effects of reinforcement and attribution on the child's developing self-concept. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Supramolecular organized multilayers composed of glucose oxidase (GOx) and osmium-derivatized poly(allylamine) redox polymer have been self-assembled electrostatically from Os-polyelectrolyte solutions of variable pH (5.5-8.8) leading to a decrease of the linear charge density in the PAH-Os with increasing pH. The layer-by-layer enzyme multilayers were studied by ellipsometry, quartz crystal microbalance, AFM, cyclic voltammetry, and electrocatalytic oxidation of beta-D-glucose. At higher adsorption solution pH, an increase in the film thickness, enzyme loading, and redox charge was observed. While the electrocatalytic response increases with the increase of the adsorption solution pH (decrease of the polyelectrolyte linear charge), the FADH2 oxidation bimolecular rate constant has a maximum in the pH range 7.0-7.5 where a change in the film growth mechanism is observed. 相似文献
70.
Maria Laura De Marchis Fiorella Guadagni Erica Silvestris Domenica Lovero David Della-Morte Patrizia Ferroni 《Critical reviews in food science and nutrition》2019,59(14):2308-2320
ABSTRACTMigraine is a common multifactorial and polygenic neurological disabling disorder characterized by a genetic background and associated to environmental, hormonal and food stimulations. A large series of evidence suggest a strong correlation between nutrition and migraine and indicates several commonly foods, food additives and beverages that may be involved in the mechanisms triggering the headache attack in migraine-susceptible persons. There are foods and drinks, or ingredients of the same, that can trigger the migraine crisis as well as some foods play a protective function depending on the specific genetic sensitivity of the subject. The recent biotechnological advances have enhanced the identification of some genetic factors involved in onset diseases and the identification of sequence variants of genes responsible for the individual sensitivity to migraine trigger-foods. Therefore many studies are aimed at the analysis of polymorphisms of genes coding for the enzymes involved in the metabolism of food factors in order to clarify the different ways in which people respond to foods based on their genetic constitution.This review discusses the latest knowledge and scientific evidence of the role of gene variants and nutrients, food additives and nutraceuticals interactions in migraine. 相似文献