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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
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Schwartz Sonia; Hoyte Joel; James Thea; Conoscenti Lauren; Johnson Renee; Liebschutz Jane 《Canadian Metallurgical Quarterly》2010,2(1):54
A dearth of literature exists on barriers to conducting research with Black male victims of community violence, despite the need for evidence-based postinjury interventions. This study used qualitative data from a cross-sectional interview study (n = 16) and a pilot intervention study (n = 11) conducted in Boston, MA to identify challenges and facilitators to conducting research with Black male victims of community violence, particularly with regard to recruitment and maintenance of a study sample. Qualitative methods, including Grounded Theory and ethnography, were used to analyze the data. Challenges included a fear of police involvement, an impression of “snitching” when disclosing personal information, mistrust of research motives, suspicion of the informed consent process, the emotional impact of the trauma itself, and logistical issues. Facilitators to research included monetary incentives and motivation to help oneself and others. Participant recommendations on recruitment methods relating to approach and timing are provided. Findings from this study may assist in the planning of research studies for Black male victims of community violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Excessive frictional loading to the skin often results in the formation of blisters, due to the transmission of shear loading
to the interfaces between dermal cell strata. The consequences of blistering range from mild discomfort to serious infection.
In some patients, such as those disposed to epidermolysis bullosa or neuropathic diabetes, blisters can severely degrade life
quality. Investigation of environmental and application parameters that affect blister formation has occurred primarily as
a qualitative, observational pursuit on human subjects, which has often led to confounding of data and lack of repeatability.
The authors have developed a Synthetic Skin Simulant Platform (3SP) that reproduces the mechanical behavior of human skin
when exposed to tribological loading. The platform is an assembled construct of bonded elastomeric layers that act as surrogates
for the epidermis, basement membrane, dermis, and subdermal structure. Epidermal (top layer) materials are typically silicone
or polyurethane films with a friction coefficient akin to human skin, while sublayers display mechanical properties similar
to their anatomical analogs. Blistering is evident optically by examining the separation voids formed after applying shear
loads to the epidermal layer. The 3SP has been used in a two-axis pin-on-flat tribometer with a stainless steel indenter to
study the normal load and friction coefficients encountered at the onset of frictional blistering. The 3SP allows for modulation
of friction coefficient, interfacial adhesion strength, and subdermal stiffness for investigation of blistering damage to
various anatomical sites. Experimental results have been compared to human test data and have shown that the 3SP provides
the potential to make significant advances with respect to skin tribology research. 相似文献
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REDUCED‐ORDER MODELS FOR FEEDBACK STABILIZATION OF LINEAR SYSTEMS WITH A SINGULAR PERTURBATION MODEL
The problem of output feedback stabilization of linear systems based on a reduced‐order model is addressed in this paper. New reduced‐order models are proposed for the output feedback design of linear systems with a singular perturbation model. An output feedback controller with a zero steady‐state gain matrix is proposed for stabilizing this kind of system. It is shown that with the proposed controller the reduced‐order model based feedback design can guarantee the actual closed‐loop stability for the sufficiently small perturbation parameter. This approach can overcome the difficulties in the existing design method using the so‐called zeroth‐order approximation model, whose validity is highly dependent on the value of the perturbation parameter. 相似文献
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The effect of three storage temperatures (0, -9 and -18 degrees C) of the kiwi-fruit pulp reduced pressure concentrate, by a period of 3 months, in the physical (soluble solids, water activity, consistency and color), chemistry (pH, acidity, ascorbic acid, chlorophyll and pheophytin) and sensorial (appearance, aroma, acidity, sweetness, color and flavor) characteristics were studied. The greater deterioration was produced in the stored pulp to 0 degree C, while to -9 degrees C there is no significative differences, on the other hand, the kiwi-fruit pulp stored to -18 degrees C maintained large part of the original characteristics. It was observed that while the temperature and storage time increased, vitamin C and chlorophyll contents decreased, varying significantly consistency, color and appearance of product. The rest of the analyzed variables did not present significative differences during storage. 相似文献
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