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101.
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices.  相似文献   
102.
The design and fabrication of a membrane-integrated microfluidic cell culture device (five layers,≤500 μm total thickness) developed for high resolution microscopy is reported here. The multi-layer device was constructed to enable membrane separated cell culture for tissue mimetic in vitro model applications and pharmacodynamic evaluation studies. The microdevice was developed via a unique combination of low profile fluidic interconnect design, substrate transfer methodology, and wet silane bonding. To demonstrate the unique high resolution imaging capability of this device, we used oil immersion microscopy to image stained nuclei and mitochondria in primary hepatocytes adhered to the incorporated membrane  相似文献   
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Many very young children attend early care and education programs, but current information about the quality of center-based care for toddlers is scarce. Using 2 observation instruments, the Infant/Toddler Environment Rating Scale–Revised (ITERS-R) and the Classroom Assessment Scoring System, Toddler Version (CLASS-Toddler), 93 child care classrooms for toddlers across the state of North Carolina, representing a range of quality, were assessed to determine overall quality, and associations between observed quality and teachers' ratings of child behavior problems and competence outcomes using the Brief Infant Toddler Social Emotional Assessment. Research Findings: Findings indicated that overall, toddler classrooms were rated as being of moderate quality. Associations between observed quality and teacher-reported child behavior problems and competence outcomes indicated that CLASS-Toddler ratings were positively associated with fewer behavior problems; specifically, children in classrooms with higher levels on the CLASS-Toddler domains of Emotional and Behavioral Support as well as Engaged Support for Learning were reported to have fewer behavior problems. Similarly, the ITERS-R subscales of Interaction and Listening and Talking were positively related to fewer reported behavior problems. Regression models showed that the CLASS-Toddler Emotional and Behavioral Support domain predicted differences in child behavior problems. Practice or Policy: Findings suggest the need for additional research related to very young children's experiences in center-based child care to examine associations between quality and child experiences and outcomes. Children's experiences over time need to be examined to understand how these early child care experiences are related to children's later school adjustment and performance. On a related note, professional development for teachers in toddler classrooms needs to be addressed in terms of preparing effective teachers for young children during the toddler developmental period.  相似文献   
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Schools are an important context for both basic and applied scientific research. Unlike the laboratory, however, the physical and social conditions of schools are not under the exclusive control of scientists. In this article, we liken collecting data in schools to putting on a theatrical production. We begin by describing the large cast of characters whose collaborative efforts make school‐based research possible. Next, we address the critics, including the university Institutional Review Board (IRB) and school administrators, whose feedback often improves the final study design. We then turn our attention to set building, stage directions, and rehearsals—key steps in the iterative process of refining study procedures. We end with a discussion of the day of data collection itself and activities that take place after the curtain drops. Throughout, we make recommendations based on our recent experience collecting data at several high schools.  相似文献   
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Abstract

Considerable research evidence supports the provision of explicit instruction for students at risk for reading difficulties; however, one of the most widely implemented approaches to early reading instruction is Guided Reading (GR; Fountas & Pinnel, 1996), which deemphasizes explicit instruction and practice of reading skills in favor of extended time reading text. This study evaluated the two approaches in the context of supplemental intervention for at-risk readers at the end of Grade 1. Students (n = 218) were randomly assigned to receive GR intervention, explicit intervention (EX), or typical school instruction (TSI). Both intervention groups performed significantly better than TSI on untimed word identification. Significant effects favored EX over TSI on phonemic decoding and one measure of comprehension. Outcomes for the intervention groups did not differ significantly from each other; however, an analysis of the added value of providing each intervention relative to expected growth with typical instruction indicated that EX is more likely to substantially accelerate student progress in phonemic decoding, text reading fluency, and reading comprehension than GR. Implications for selection of Tier 2 interventions within a response-to-intervention format are discussed.  相似文献   
108.
Over the past decade, repeated calls have been made to incorporate more active teaching and learning in undergraduate biology courses. The emphasis on inquiry-based teaching is especially important in laboratory courses, as these are the courses in which students are applying the process of science. To determine the current state of research on inquiry-based teaching in undergraduate biology laboratory courses, we reviewed the recent published literature on inquiry-based exercises. The majority of studies in our data set were in the subdisciplines of biochemistry, cell biology, developmental biology, genetics, and molecular biology. In addition, most exercises were guided inquiry, rather than open ended or research based. Almost 75% of the studies included assessment data, with two-thirds of these studies including multiple types of assessment data. However, few exercises were assessed in multiple courses or at multiple institutions. Furthermore, assessments were rarely based on published instruments. Although the results of the studies in our data set show a positive effect of inquiry-based teaching in biology laboratory courses on student learning gains, research that uses the same instrument across a range of courses and institutions is needed to determine whether these results can be generalized.  相似文献   
109.
The increase in smartphone adoption has been no less than astounding. Unfortunately, the explosive growth has been accompanied by a rash of security problems. A contributing factor to the growing security problem is a lack of education, training, and awareness. In addition, “bring your own device” (BYOD) policies often leave security responsibilities to the competencies of device owners, which compromises security. Today’s students are tomorrow’s employees with responsibilities for protecting their work environment. They need to understand and practice a full-range of mobile security practices so that they can safely access the information assets of their organizations. If students are not engaging in such practices, educational institutions have a responsibility to ensure that students understand how to keep information assets secure. This paper investigates the smartphone security practices of undergraduate college students. Five hundred students in business classes at a regional public university were surveyed to determine their use of recommended smartphone security practices. The study found that many smartphone users did employ some security measures, but a high percentage of them were ignoring potential risks. This suggests a need for increased education, training, and awareness.  相似文献   
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