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21.
Arnold Chen Royal Wang Candace R. S. Bever Siyuan Xing Bruce D. Hammock Tingrui Pan 《Biomicrofluidics》2014,8(6)
The emerging technologies on mobile-based diagnosis and bioanalytical detection have enabled powerful laboratory assays such as enzyme-linked immunosorbent assay (ELISA) to be conducted in field-use lab-on-a-chip devices. In this paper, we present a low-cost universal serial bus (USB)-interfaced mobile platform to perform microfluidic ELISA operations in detecting the presence and concentrations of BDE-47 (2,2′,4,4′-tetrabromodiphenyl ether), an environmental contaminant found in our food supply with adverse health impact. Our point-of-care diagnostic device utilizes flexible interdigitated carbon black electrodes to convert electric current into a microfluidic pump via gas bubble expansion during electrolytic reaction. The micropump receives power from a mobile phone and transports BDE-47 analytes through the microfluidic device conducting competitive ELISA. Using variable domain of heavy chain antibodies (commonly referred to as single domain antibodies or Nanobodies), the proposed device is sensitive for a BDE-47 concentration range of 10−3–104 μg/l, with a comparable performance to that uses a standard competitive ELISA protocol. It is anticipated that the potential impact in mobile detection of health and environmental contaminants will prove beneficial to our community and low-resource environments. 相似文献
22.
OBJECTIVE: This study compares homeless women who had childhood histories of foster care or other out-of-home placement to those who have not. METHOD: A countywide probability sample of homeless women (n = 179) received structured interviews. RESULTS: One-third of homeless women reported being raised apart from their parents. Among women with children under age 18, most (61.5%) had children who had lived in foster care or other out-of-home placements. Variables associated with homeless mothers' children living in foster care or other out-of-home placements were: Child was school-age, mother was age 35 or older, mother had a current alcohol or drug use disorder, mother experienced childhood sexual abuse, and mother ran away from home (when under age 18). CONCLUSIONS: Parenting is difficult for homeless mothers who may need to place their children with others to facilitate school attendance. Parent-child interaction may be problematic in family shelters where privacy is rare. Thus, programs promoting family preservation for homeless mothers should provide parenting support as well as permanent housing. 相似文献
23.
T. S. Robertson 《Educational research; a review for teachers and all concerned with progress in education》2013,55(3):189-197
Social class has always been one of the most prominent variables in educational research, yet the various ways of classifying it have never ceased to be controversial. The author reviews the major classifications, assesses their validity, surveys the use made of them in research literature, suggests how they should be interpreted, and assesses to what degree findings couched in these terms correspond to the reality of social differences in Britain. 相似文献
24.
Margaret J. Robertson 《高等教育研究与发展》2017,36(7):1463-1475
Team supervision of doctoral students adds new dimensions and complexities to relationships within the teams that impact functionality of the team. Trust emerged as a significant theme in recent qualitative research into the quality of team supervision of doctoral students. Trust was cited as a key component in successful team collaborations, and the missing component in dysfunctional teams. Definitions refer to trust as the belief of truthfulness, reliability or faith in another person’s abilities. My hypothesis is that trust operates as a form of power in team supervision. It is a form of power that enables voice, resilience and creativity in teams. This article concludes that placing trust in others in supervisory teams is a deliberate decision by candidates and supervisors. It is a decision to engage in a team context despite known risks and may be understood as a gamble on the reliability of others in the expectation of reciprocity. By conceptualising trust as a form of power, strategies that engender and maintain trust may be utilised more intentionally. 相似文献
25.
Elisa S. Shernoff Adam J. Lekwa Linda A. Reddy Candace Coccaro 《Journal of educational and psychological consultation》2017,27(4):459-485
The purpose of this qualitative study was to examine teachers’ attitudes and experiences with coaching. This study was conducted in advance of a planned randomized controlled trial of a coaching intervention to better align the model with teachers’ needs and goals. Thirty-four K–5 general (n = 26), special education (n = 6), and educational support staff (n = 2) working in two high-poverty schools participated in focus groups. Interrater reliability between independent coders was high (К = 0.92; range: 0.76–1.0). Thematic analyses identified facilitators and barriers to teacher participation in the planned intervention and were used to improve upon the existing coaching model. Themes focused on advantages and disadvantages to coaching and characteristics of effective coaches and coaching models. Implications of findings for research and practice are discussed. 相似文献
26.
Robert L. Robertson 《PRIMUS》2017,27(6):606-617
Calculating Laplace transforms from the definition often requires tedious integrations. This paper provides an integration-free technique for calculating Laplace transforms of many familiar functions. It also shows how the technique can be applied to probability theory. 相似文献
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Currently, there is a lack of appropriate skill assessments available for use in golf. The aim of this study was to examine the discriminative validity and the test-retest reliability of the newly developed "Nine-Ball Skills Test". Participants of two ability levels (elite, n = 14; high-level amateur, n = 16) each hit nine golf shots of differing combinations of trajectory (straight, fade, draw) and height (normal, high, low) at an individually determined target area. Each shot was scored on its percent error index from the target and whether it achieved the maximum height as required. Participants completed the test twice using a 5-iron club. The elite group scored significantly higher (P < 0.05) than the amateur group for both the first and second rounds of the test as well as the combined scores. The between-round test-retest reliability was deemed to be not acceptable, thus we propose that the test's protocol should include use of the two rounds as standard. Due to the importance of ball striking and flight control to performance in golf, the Nine-Ball Skills Test is appropriate for providing a measure of this skill component in elite and high-level amateur golfers. 相似文献