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11.
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells.  相似文献   
12.
We discuss Konstantinos Alexakos, Jayson Jones and Victor Rodriguez’s hermeneutic study of formation and function of kinship-like relationships among inner city male students of color in a college physics classroom. From our Critical Complexity Science framework we first discuss the reading erlebnisse of students laughing at and with each other as something that immediately captured our attention in being transformative of the classroom. We continue by exploring their classroom and research experience as an emergent structure modifying their collective as well as their individual experiences. As we analyze both the classroom and the research space as a complex system, we reflect on the instructor/students interactions characterized by an asymmetrical “power” relationship. From our analysis we propose to consider the zone of proximal development as the constantly emerging and transforming person experience (erlebnisse and erfahrung).  相似文献   
13.
Quality indicators (QIs) measure the extent to which set targets are attained and provide a quantitative basis for achieving improvement in care and, in particular, laboratory services. A body of evidence collected in recent years has demonstrated that most errors fall outside the analytical phase, while the pre- and post-analytical steps have been found to be more vulnerable to the risk of error. However, the current lack of attention to extra-laboratory factors and related QIs prevent clinical laboratories from effectively improving total quality and reducing errors. Errors in the pre-analytical phase, which account for 50% to 75% of all laboratory errors, have long been included in the ‘identification and sample problems’ category. However, according to the International Standard for medical laboratory accreditation and a patient-centered view, some additional QIs are needed. In particular, there is a need to measure the appropriateness of all test request and request forms, as well as the quality of sample transportation. The QIs model developed by a working group of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) is a valuable starting point for promoting the harmonization of available QIs, but further efforts should be made to achieve a consensus on the road map for harmonization.  相似文献   
14.
Pseudoscience is error, substantive or methodological, parading as science. Obvious examples are parapsychology, ??intelligent design,?? and homeopathy. Psychoanalysis and pop evolutionary psychology are less obvious, yet no less flawed in both method and doctrine. The fact that science can be faked to the point of deceiving science lovers suggests the need for a rigorous sifting device, one capable of revealing out the worm in the apple. This device is needed to evaluate research proposal as well as new fashions. Such a device can be designed only with the help of a correct definition of science, one attending not only to methodological aspects, such as testability and predictive power, but also to other features of scientific knowledge, such as intelligibility, corrigibility, and compatibility with the bulk of antecedent knowledge. The aim of this paper is to suggest such a criterion, to illustrate it with a handful of topical examples, and to emphasize the role of philosophy in either promoting or blocking scientific progress. This article is a revised version of a chapter in the author??s forthcoming book Matter and Mind (Springer). [The Appendix on inductive logic was written at the request of the editors in order to elaborate claims made in #10 (4).]  相似文献   
15.
This article presents an analysis of the concept of disability in Amartya Sen’s capabilities and functionings approach in the context of Information and Communication Technologies (ICT). Following a critical review of the concept of disability—from its traditional interpretation as an essentially medical concept to its later interpretation as a socially constructed category—we will introduce the concept of functional diversity. The importance of human diversity in the capabilities and functionings approach calls for incorporating this concept into the analysis of well-being and quality of life in persons with disability—aspects in which ICT currently plays a major role. When one contemplates these technologies, it becomes clear that factors such as accessibility, design for all, and user participation in development and implementation processes are key strategies in promoting equal rights and equal opportunity for persons with disability in the different environments of the information society.  相似文献   
16.
We investigated the effects of hand paddles and parachute on the relative duration of stroke phases and index of coordination of competitive crawl-strokers. Eleven male-swimmers (age: 21.9 ± 4.5 years; 50-m best time: 24.23 ± 0.75 s) were evaluated in four maximal-intensity conditions: without equipment, with hand paddles, with parachute, and with both hand paddles and parachute. Relative stroke phase duration of each arm, swimming velocity, and stroke rate were analysed from video (60 Hz). The index of coordination was quantified based on the lag time between propulsive phases of each arm, which defined the coordination mode as catch-up, opposition or superposition. The stroke rate decreased in all conditions (P < 0.05) and swimming velocity decreased with parachute and with paddles + parachutes (P < 0.05). The coordination mode changed from catch-up in free swimming (-2.3 ± 5.0%) to opposition with paddles (-0.2 ± 3.8%), parachute (0.1 ± 3.1%), and paddles + parachute (0.0 ± 3.2%). Despite these variations, no significant differences were observed in relative duration of right and left arm-stroke phases, or in index of coordination. We conclude that the external resistances analysed do not significantly influence stroke phase organization, but, as a chronic effect, may lead to greater propulsive continuity.  相似文献   
17.
Learning Environments Research - The pedagogical beliefs of novice teachers and their coaches throughout a two-year induction program and how those beliefs impact their induction experiences were...  相似文献   
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19.
Children at risk for early reading difficulties were identified on entry into kindergarten, and half of these children received small-group intervention two to three times a week during their kindergarten year. The other half received whatever remedial assistance was offered by their home schools. These children were again assessed at the beginning of first grade, and those who continued to have difficulties in reading received either one-to-one daily tutoring offered by project teachers from the beginning to the end of first grade or whatever remedial assistance was offered by their home schools over the same time period. All target children were periodically assessed through the end of third grade. Results suggest that either kindergarten intervention alone or kindergarten intervention combined with first-grade intervention are both useful vehicles for preventing early and long-term reading difficulties in most at-risk children.  相似文献   
20.
The following excerpts are from Chapter Two of Mario D. Fantini's 1986 Regaining Excellence in Education, reprinted by permission of Merrill Publishing Company.  相似文献   
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