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1.
The main purpose of this study was to explore the factors mediating the translation of second grade teachers’ nature of science (NOS) views into classroom practice after completing a graduate level NOS course. Four second grade in-service elementary teachers comprised the sample of this study. Data were collected from several sources during the course of this study. The primary data sources were (a) assessment of the elementary teachers’ NOS views before and after the graduate level NOS course using the Views of Nature of Science Questionnaire Version B (VNOS-B) (Lederman et al., 2002) coupled with interviews, and (b) a classroom observation and videotaped recording of the elementary teachers’ best NOS lessons coupled with interview. We identified three distinct but related factors that mediated the translation of NOS views into classroom practice: the teachers’ perspectives about the developmental appropriateness of the NOS aspect, the teachers’ selection of target NOS aspects, and the relative importance placed by teachers on each NOS aspect.  相似文献   
2.

Background:

The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.

Materials and methods:

Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.

Results:

The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.

Conclusion:

We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels.  相似文献   
3.
We report on reversible electroporation of cells in a flow-through microfluidic device, whereby the required electric field is delivered through a set of integrated microcapillaries between a centre stream of cells and side streams of liquid electrolytes. The electrolytes are applied with a sine wave voltage and cells flow by the microcapillary openings encounter a burst of ac field with a duration and strength determined by their average speed and spatial proximity to the microcapillary openings, respectively. Effectiveness of the approach is presented through numerical simulations and empirical results on electroporation efficiency and cell viability against various flow rates (exposure time to the field) as well as frequencies and root-mean-square (rms) intensities of the field. High frequencies (80–400 kHz) and high intensities (e.g., 1.6 kV/cm, rms) are identified with increased electroporation efficiency 61% and viability 86% on average. These results suggest that the device demonstrated here with a simple design and robust operation offers a viable platform for flow-through electroporation.  相似文献   
4.
Daylighting, a controlled architectural tool that influences users' perception and behavior, in university libraries and their influences on users' preference and satisfaction was examined in this study. The effects of daylighting in coordination with visual comfort, on university library users were measured in relation to four environmental processes, namely privacy, personal space, territoriality, and crowding. It was found that daylight and four environmental processes are related. It is believed that the consideration of this relationship will encourage students to use their libraries fully as an essential component of university education and campus life.  相似文献   
5.
We demonstrate monolithic integration of fine cylindrical glass microcapillaries (diameter ∼1 μm) on silicon and evaluate their performance for electrophoretic separation of biomolecules. Such microcapillaries are achieved through thermal reflow of a glass layer on microstructured silicon whereby slender voids are moulded into cylindrical tubes. The process allows self-enclosed microcapillaries with a uniform profile. A simplified method is also described to integrate the microcapillaries with a sample-injection cross without the requirement of glass etching. The 10-mm-long microcapillaries sustain field intensities up to 90 kV/m and limit the temperature excursions due to Joule heating to a few degrees Celsius only.  相似文献   
6.
Abstract

The paper summarizes the results of a series of focus group interviews with Chinese teaching assistants and US undergraduates on their perceptions about teaching and teachers in their own and US cultures. Focus group interviews were held with Chinese math‐based science teaching assistants (CTAs) who were at three different stages of the teacher preparation process. Similarly, American undergraduates’ perceptions were elicited through focus group interviews and questionnnaires. CTAs viewed American college instructors as exciting, but unclear in their organization and presentation. Undergraduates thought ideal US professors should spend more time with their students, and have interpersonal skills in teaching. They did not value the professor's knowledge of the subject matter as much as CTAs did. Implications for future TA development programmes are also discussed.  相似文献   
7.
Simultaneous group confirmatory factor analyses of the Psychopathy Checklist‐Revised (PCL‐R; Hare, 1991) were conducted with an alcoholic inpatient sample (N= 740). Invariance of the item‐factor relations for the 2 highly correlated factors of Personality and Behavioral Features were supported across 3 racial/ethnic groups (African American, Puerto Rican, and White) and across gender groups. Moment structure analysis indicated no significant differences in the latent means across men and women. Alternative covariance structure models were specified within a multitrait‐multimethod framework to evaluate convergent and discriminant validity across different methods of measuring antisociality. A correlated trait‐correlated method model was supported. A factor intercorrelation of .68 was indicated for Personality and Behavioral Features, and a significant correlation (.40) among method factors emerged for the PCL‐R scores across different raters (interviewers and therapists). General support was provided for the use of the PCL‐R with alcoholic inpatients, though there was a substantial intercorrelation for the factors of Personality and Behavioral Features.  相似文献   
8.
9.
Museums are used in every discipline to collect, classify, and present information for scientific purposes. They also serve as an effective educational medium. Since the establishment of a boutique anatomy museum at Bahçeşehir University, lectures, conferences, and seminars have been organized there over the past four years on the history of human anatomy and the human body. In order to raise awareness about the need to make anatomy accessible to kindergarteners and school-aged children, rather than exclusively to undergraduate students, activities that are suited to a wide range of ages have been developed at the museum and at the anatomy laboratory. Four different sessions were conducted, including activities such as lectures using plastic models as props, shaping organs out of playdough, anatomy puzzles, watching cartoons, and examining specimens through a microscope. Healthy and pathologic anatomies were chosen to match daily themes. Among the kindergarteners and elementary school children, no grading was done, nor was any questionnaire administered; however, a survey was administered in the 10–12 age group (N = 64). According to the students' written feedback, 93.75% said they “are happy with microscope activities” while 84.37% said they “had so much fun” participating in the playdough activities. However, 18.75% criticized the activities, saying they “could have been longer.” In conclusion, it is believed that these “getting to know our bodies” activities that were hosted in the anatomy museum, including conferences, workshops, material preparation, and instructional movies, may play an important role in the development of a healthy society.  相似文献   
10.
The purpose of this paper is to describe the development process and the key components of a computer-assisted histology material. Computer-assisted histology material is designed to supplement traditional histology education in a large Midwestern university. Usability information of the computer-assisted instruction (CAI) material was obtained through formative research methodology. Findings indicate that computer-assisted instruction should be used as complimentary to traditional histology instruction.  相似文献   
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