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91.
92.
We describe a microfluidic device for on-chip chemical processing, such as staining, and subsequent washing of cells. The paper introduces “separator walls” to increase the on-chip incubation time and to improve the quality of washing. Cells of interest are concentrated into a treatment stream of chemical reagents at the first separator wall for extended on-chip incubation without causing excess contamination at the output due to diffusion of the unreacted treatment chemicals, and then are directed to the washing stream before final collections. The second separator wall further reduces the output contamination from diffusion to the washing stream. With this approach, we demonstrate on-chip leukocyte staining with Rhodamine 6G and washing. The results suggest that other conventional biological and analytical processes could be replaced by the proposed device.  相似文献   
93.
Based on our community engagement project involving 47 older, low-income African-American adults from a senior community center, this study analyzes how an underserved population acquires knowledge and skills related to digital technologies. We discuss the conceptualization, implementation, and evaluation of a weekly, four-month long computer class for members of the senior community center. Our mixed-method research shows the importance of taking into account both the multidimensional nature of adult learning and the social and cultural contexts in which learning occurs when working with underserved adult populations. Findings from our formative and evaluative research offer insights into changes in the computer class participants’ attitudes toward and perspectives on key digital literacy issues including security and privacy online and online information verification. Scholarly and policy implications are discussed in the context of digital competency and adult learning for marginalized populations.  相似文献   
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95.
Perceptions of adolescent–parent and adolescent–peer relationship qualities, and adolescents’ attachment states of mind were examined as predictors of adult social and romantic relationship quality, depressive symptoms, and work performance. Adolescents (86 male, 98 female; 58% White, 29% African American, 8% mixed race/ethnicity, 5% other groups) were followed from age 13 to 24 via observational, self-, parent-, and close friend-reports. Adolescent close friendship quality was a significantly better predictor of adult peer and romantic outcomes, work performance, and depressive symptoms than parental reports of the parent–teen relationship; attachment security was also a strong predictor of numerous outcomes. Results are interpreted as reflecting the difficulty for parents judging parent–teen relationship quality and as reflecting the growing importance of close friendships during this period.  相似文献   
96.
In both the literature on inclusive education and in international policy development, there has been considerable interest in the use of sets of indicators for the implementation of inclusive education at national and local levels. Drawing on sets of indicators developed in Europe and the Pacific Islands, this study proposes a set of such indicators for Kuwait. These indicators are then presented in a survey of 161 special education teachers working in public elementary mainstream schools across Kuwait. Analysis of the results is used to explore how such indicators could play a role in promoting policy implementation for inclusive education in Kuwait and more widely in Gulf Cooperation Council (GCC) countries.  相似文献   
97.
98.
Eccentric contractions that provide spring energy can also cause muscle damage. The aim of this study was to explore leg and vertical stiffness following muscle damage induced by an eccentric exercise protocol. Twenty active males completed 60 minutes of backward-walking on a treadmill at 0.67 m/s and a gradient of ? 8.5° to induce muscle damage. Tests were performed immediately before; immediately post; and 24, 48, and 168 hours post eccentric exercise. Tests included running at 3.35 m/s and hopping at 2.2 Hz using single- and double-legged actions. Leg and vertical stiffness were measured from kinetic and kinematic data, and electromyography (EMG) of five muscles of the preferred limb were recorded during hopping. Increases in pain scores (over 37%) occurred post-exercise and 24 and 48 hours later (p < 0.001). A 7% decrease in maximal voluntary contraction occurred immediately post-exercise (p = 0.019). Changes in knee kinematics during single-legged hopping were observed 168 hours post (p < 0.05). No significant changes were observed in EMG, creatine kinase activity, leg, or vertical stiffness. Results indicate that knee mechanics may be altered to maintain consistent levels of leg and vertical stiffness when eccentric exercise-induced muscle damage is present in the lower legs.  相似文献   
99.
Sixty female hooded rats received 70 shock-escape training trials with shock- and safeboxes similar or dissimilar to each other and nonshock (safebox) confinement durations of 5 sec or 20 sec. (Shockbox confinement duration prior to shock onset was 5 sec.) In each confinement condition performance under the similar shock/safe condition was reliably poorer than that under the dissimilar condition. Safebox confinement duration negligibly affected performance under the dissimilar condition, while in the similar condition increasing confinement duration reliably facilitated performance. Comparisons with control data suggest that facilitation of escape was due to the relative shock-safe confinement duration rather than to absolute safebox confinement.  相似文献   
100.
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