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11.
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
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Esther Ntuli Arnold Nyarambi Moussa Traore 《Journal of Research in Special Educational Needs》2014,14(4):221-228
Research indicates that early childhood professionals gather assessment information to monitor child development and learning, to guide curriculum planning and decision making, to identify children who may have special needs, to report and communicate with others, and to evaluate programmes. A review of literature indicates that immigrant children have low achievement assessment scores as compared with mainstream American children, also immigrant children enter kindergarten already behind their mainstream American peers. The current study explored early childhood teachers' perceptions of assessment measures used with immigrant children and the challenges faced when assessing immigrant children. Findings of the study reveal that there are several factors that make early childhood teachers fail to gather effective assessment information from immigrant children. Unless the factors are addressed, planning for effective curriculum for immigrant children using assessment data will continue to be a challenge for early childhood teachers. Factors that continue to affect gathering effective assessment data from immigrant children include language barriers, cultural clashes, socio‐economic factors, and culturally and linguistically biased assessment measures. 相似文献
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BackgroundStochastic resonance stimulation (SRS) transmits subsensory electrical Gaussian white noise into the body to enhance sensorimotor function. This therapy has improved static single leg balance in subjects with functional ankle instability. However, the effect of this stimulation on dynamic single leg balance is not known. Improvements in dynamic single leg balance with SRS may have implications for enhancing functional rehabilitation for ankle instability. Thus, the purpose of this study was to determine the effects of SRS on dynamic single leg balance in subjects with functional ankle instability.MethodsThis study was an experimental research design and data were collected in a sports medicine research laboratory. Twelve subjects with functional ankle instability (69 ± 15 kg; 173 ± 10 cm; 21 ± 2 years) reported a history of ankle sprains and instability at the ankle with physical activity. A single leg jump-landing test was used to assess dynamic balance. Subjects were required to jump between 50% and 55% of the maximal vertical jump height, land on a single leg atop a force plate, and stabilize as quickly as possible. Jump-landing tests were performed with and without SRS. Three trials were performed for each treatment condition (SRS and control). A randomized block design was used to determine test order. Anterior/posterior and medial/lateral time-to-stabilization were computed to assess dynamic balance. Lesser time indicated better stability. One-tailed paired samples t tests were used for analysis (α ≤ 0.05).ResultsSRS improved anterior/posterior time-to-stabilization (stochastic resonance = 1.32 ± 0.31 s, control = 1.74 ± 0.80 s, p = 0.03), but did not enhance medial/lateral time-to-stabilization (stochastic resonance = 1.95 ± 0.40 s, control = 1.92 ± 0.48 s, p = 0.07).ConclusionClinicians might use SRS to facilitate balance improvements with sagittal plane dynamic single leg balance exercises that patients may not be able to perform otherwise. 相似文献
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Rebeca Fernandes Ferreira Lima Marcela Raffaelli Normanda Araujo de Morais Juliana P. Santana Carlos J. Nieto Silvia H. Koller 《Child development》2020,91(4):1237-1253
Trajectories of adjustment were examined in a sample of street-involved youth across a 1-year period. Participants (N = 113; Mage = 14.18 years; 80.5% male, 91% non-White) were recruited in three Brazilian cities. Interviews conducted at three time points included six measures of physical and psychological adjustment. Unconditional growth models revealed linear declines over time (i.e., improved adjustment) on three indicators: health symptoms, sexual risk behaviors, and negative affect. There were no linear changes in drug use, positive affect, or life satisfaction. Conditional growth models revealed few significant effects for age or gender, but ratings of stressful life events moderated longitudinal changes in health symptoms, drug use, and negative affect. Implications for practice, policy, and theory are discussed. 相似文献
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This article explores how innovations in the funeral industry borrow from the technological affordances, commercial logics, cultural norms, and affective registers of social media platforms. Based on ethnographic research of funeral industry conventions, we analyze examples of funeral planning tools, funeral service mediation, and digital memorialization products. We consider how these products aim to capture forms of data, affect, and value as part of the funeral industry’s efforts to shore up their historically intermediary relevance in the face of potential “disruption” from technological innovation, and threats of marginalization posed by shifting norms of networked grieving and commemoration in digital culture 相似文献
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We investigated whether the layout of type in two popular children’s reading schemes was suitable for the intended reading age. 120 children read four passages of text that adopted the typography of four reading stages in each of the two schemes. The size and spacing of the texts decreased with successive stages as the intended reading age increased. The reading speed of children aged 5 to 7 years decreased as the text size decreased: in particular, these children read fastest the text designed for 5 and 6 year olds. Older children aged 8 to 11 years were neither assisted nor disadvantaged by text size. Children of all ages, particularly those susceptible to visual stress, were found to make more errors on the smaller than on the larger text. We conclude that the reading development of some children might benefit from a larger text size and spacing than is currently the norm, and that no children would be disadvantaged by such a change. 相似文献