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271.
Kersten Alan W.; Meissner Christian A.; Lechuga Julia; Schwartz Bennett L.; Albrechtsen Justin S.; Iglesias Adam 《Canadian Metallurgical Quarterly》2010,139(4):638
Three experiments provide evidence that the conceptualization of moving objects and events is influenced by one's native language, consistent with linguistic relativity theory. Monolingual English speakers and bilingual Spanish/English speakers tested in an English-speaking context performed better than monolingual Spanish speakers and bilingual Spanish/English speakers tested in a Spanish-speaking context at sorting novel, animated objects and events into categories on the basis of manner of motion, an attribute that is prominently marked in English but not in Spanish. In contrast, English and Spanish speakers performed similarly at classifying on the basis of path, an attribute that is prominently marked in both languages. Similar results were obtained regardless of whether categories were labeled by novel words or numbered, suggesting that an English-speaking tendency to focus on manner of motion is a general phenomenon and not limited to word learning. Effects of age of acquisition of English were also observed on the performance of bilinguals, with early bilinguals performing similarly in the 2 language contexts and later bilinguals showing greater contextual variation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
272.
The investigation summarised in this paper applied a sustainability assessment methodology on a renewable energy technological system in a rural village project that was commissioned by the South African Department of Minerals and Energy. The project comprised of wind, solar and lead-acid battery energy storage technologies that were implemented as a mini-hybrid off-grid electrification system for the village. The sustainability assessment methodology predicts the outcomes of such interventions by way of a learning model using discipline experts in the fields of economics, sociology, ecosystem sustainability, institutional governance, and the physics and chemistry of energy conversion processes. The comparison of the project's outcomes with a South African sustainable development framework shows that the specific village renewable off-grid electrification system is not viable. The main reason is that charges for electricity supply costs in village grids are too high for available subsidies; the economies of scale for renewable energy supply technologies favour national grids. The failure of the integrated system may also be attributable to the complexity of the social-institutional sub-system, which resulted in uncertainty for project planners and system designers, and the lack of resilience of the technological system to demands from the socio-economic and institutional sub-systems. Policy-related recommendations are made accordingly. 相似文献
273.
The entertainment industry, primarily the video games industry, continues to dictate the development and performance requirements
of graphics hardware and computer graphics algorithms. However, despite the enormous progress in the last few years, it is
still not possible to achieve some of industry’s demands, in particular high-fidelity rendering of complex scenes in real-time,
on a single desktop machine. A realisation that sound/music and other senses are important to entertainment led to an investigation
of alternative methods, such as cross-modal interaction in order to try and achieve the goal of “realism in real-time”. In
this paper we investigate the cross-modal interaction between vision and audition for reducing the amount of computation required
to compute visuals by introducing movement related sound effects. Additionally, we look at the effect of camera movement speed
on temporal visual perception. Our results indicate that slow animations are perceived as smoother than fast animations. Furthermore,
introducing the sound effect of footsteps to walking animations further increased the animation smoothness perception. This
has the consequence that for certain conditions, the number of frames that need to be rendered each second can be reduced,
saving valuable computation time, without the viewer being aware of this reduction. The results presented are another step
towards the full understanding of the auditory-visual cross-modal interaction and its importance for helping achieve “realism
int real-time”. 相似文献
274.
Alan D. Mighell 《Journal of research of the National Institute of Standards and Technology》2011,116(2):589-597
An inspection of the recent literature reveals that polymorphism is a frequently encountered phenomenon. The recognition of polymorphic forms plays a vital role in the materials sciences because such structures are characterized by different crystal packing and accordingly have different physical properties. In the pharmaceutical industry, recognition of polymorphic forms can be critical for, in certain cases, a polymorphic form of a drug may be an ineffective therapeutic agent due to its unfavorable physical properties. A check of the recent literature has revealed that in some cases new polymorphic forms are not recognized. In other instances, a supposedly new polymeric form is actually the result of an incorrect structure determination. Fortunately, lattice-matching techniques, which have proved invaluable in the identification and characterization of crystal structures, represent a powerful tool for analyzing polymorphic forms. These lattice-matching methods are based on either of two strategies: (a) the reduced cell strategy–the matching of reduced cells of the respective lattices or (b) the matrix strategy–the determination of a matrix or matrices relating the two lattices coupled with an analysis of the matrix elements. Herein, these techniques are applied to three typical cases–(a) the identification of a new polymorphic form, (b) the demonstration that a substance may not be a new polymorphic form due to missed symmetry, and (c) the evaluation of pseudo polymorphism because of a missed lattice. To identify new polymorphic forms and to prevent errors, it is recommended that these lattice matching techniques become an integral part of the editorial review process of crystallography journals. 相似文献
275.
Burkard Alan W.; Pruitt Nathan T.; Medler Barbara R.; Stark-Booth Ann M. 《Canadian Metallurgical Quarterly》2009,3(1):37
In this paper, the authors report on the development and initial psychometric evaluation of the Lesbian, Gay, and Bisexual Working Alliance Self-Efficacy Scales (LGB-WASES) with data collected from two studies and 534 counseling trainees. Exploratory factor analysis results yielded a 32-item scale with a three-factor model (a) Emotional Bond, (b) Establishing Tasks, and (c) Setting Goals. LGB-WASES scores were internally consistent and remained stable over a 3-week period. Construct validity evidence suggests the LGB-WASES scores were (a) positively related to general perceptions of counseling self-efficacy and multicultural counseling competency, (b) negatively related to attitudes toward lesbians and gay men, and (d) unrelated to social desirability. Recommendations for future research are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
276.
277.
Scott A. Eastman Alan J. Lesser Thomas J. McCarthy 《Journal of Materials Science》2009,44(5):1275-1282
A composite fabrication method is reported that incorporates silicones into bulk aspen substrates and subsequently crosslinks
the additives in situ. This process utilizes supercritical CO2, a non-toxic and easily recoverable solvent, as a transport and reaction medium resulting in aspen composites that have been
uniformly infused with silicone. Flexure properties of aspen–silicone composites were determined to be indistinguishable from
those of aspen. However, after thermal degradation, the residual flexure properties of the composite char were significantly
improved compared to the virgin aspen char. Energy release rate, total energy released, and char yield of aspen and aspen–silicone
composites were measured and a significant improvement in all three of these fire-resistance parameters was observed after
the incorporation of silicone. Samples were also exposed to a controlled thermo-oxidative environment under an applied stress
to measure lifetimes of each sample at given temperatures and stress levels. This data were subjected to an Arrhenius analysis
and show a good linear correlation. Composite systems demonstrate significantly longer lifetimes than virgin aspen and the
slopes of all lines are nearly identical, suggesting that no change in the chemical degradation mechanism has occurred. 相似文献
278.
Steven J. Vance Rhona E. McDonald Alan Cooper Brian O. Smith Malcolm W. Kennedy 《Journal of the Royal Society Interface》2013,10(85)
Latherin is a highly surface-active allergen protein found in the sweat and saliva of horses and other equids. Its surfactant activity is intrinsic to the protein in its native form, and is manifest without associated lipids or glycosylation. Latherin probably functions as a wetting agent in evaporative cooling in horses, but it may also assist in mastication of fibrous food as well as inhibition of microbial biofilms. It is a member of the PLUNC family of proteins abundant in the oral cavity and saliva of mammals, one of which has also been shown to be a surfactant and capable of disrupting microbial biofilms. How these proteins work as surfactants while remaining soluble and cell membrane-compatible is not known. Nor have their structures previously been reported. We have used protein nuclear magnetic resonance spectroscopy to determine the conformation and dynamics of latherin in aqueous solution. The protein is a monomer in solution with a slightly curved cylindrical structure exhibiting a ‘super-roll’ motif comprising a four-stranded anti-parallel β-sheet and two opposing α-helices which twist along the long axis of the cylinder. One end of the molecule has prominent, flexible loops that contain a number of apolar amino acid side chains. This, together with previous biophysical observations, leads us to a plausible mechanism for surfactant activity in which the molecule is first localized to the non-polar interface via these loops, and then unfolds and flattens to expose its hydrophobic interior to the air or non-polar surface. Intrinsically surface-active proteins are relatively rare in nature, and this is the first structure of such a protein from mammals to be reported. Both its conformation and proposed method of action are different from other, non-mammalian surfactant proteins investigated so far. 相似文献
279.
280.
Redox-active films have been generated via electrochemical reduction in a solution containing palladium(II) acetate and [C60]fullerene, or derivatives of C60. The C60 derivatives include piperazine (piperazine-C60), pyrrolidine (CH3-pyr-C60), and a pyrrolidine salt, [(CH3)2-pyr-C60]+ attached to the fullerene unit. In these films, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. The polymer yields involving the piperazine and pyrrolidine derivatives of C60 are significantly lower than the yield of the C60/Pd film. The CH3-pyr-C60/Pd and [(CH3)2-pyr-C60]+/Pd films are electrochemically active in the negative potential region due to the reduction of the fullerene moiety. Reduction of the CH3-pyr-C60/Pd film is accompanied by the transport of supporting electrolyte cations from the solution into the film. In the first reduction step of the [(CH3)2-pyr-C60]+/Pd film, both cations and anions of the supporting electrolyte are involved. The piperazine-C60/Pd film exhibits electrochemical activity at both negative and positive potentials. In the negative potential region, reduction of the fullerene cage takes place. Oxidation of the piperazine moiety is responsible for the observed current in the positive potential range. Here, the oxidation process of this polymer is significantly influenced by the presence of metallic palladium particles in the film. 相似文献