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Salmanzadeh A Kittur H Sano MB C Roberts P Schmelz EM Davalos RV 《Biomicrofluidics》2012,6(2):24104-2410413
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool. 相似文献
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This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent. 相似文献
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OBJECTIVES: To examine the effects of different forms of family violence at two developmental stages by assessing a sample of 110 Israeli children, drawn from the case files of Israeli family service agencies, studied longitudinally in both middle childhood and adolescence. METHODS: Information about the children's adjustment was obtained from parents, teachers, and the children themselves when the children averaged 10.6 and 15.9 years of age using the Child Behavior Checklist (CBCL), Teacher Report Form (TRF), Youth Self-Report (YSR), and Children's Depression Inventory (CDI). Information about the history of family violence was obtained from the mothers, fathers, children, and social workers. RESULTS: The results paint a mixed picture of the effects of family violence on children and adolescents. The relationship between concurrent behavior problems and abuse group varied by informant and study phase, although they were strongest when children were the informants. Predictions regarding the relationship between early abuse and later adjustment were only partially confirmed. Different informants did not agree about which groups of children were most adversely affected, there was little stability over time in the pattern of reported effects, and children were more likely than other informants to report levels of maladjustment that varied depending on recent or concurrent exposure to family violence. Many families changed their abuse status over time, and children who were new victims at follow-up had the most internalizing problems. Girls were found to be at more risk for internalizing and externalizing behavior problems than boys. CONCLUSIONS: Multiple informants are necessary to evaluate and assess the effects of family violence on children's behavior. Younger children may be more susceptible to the effects of family violence than older children, but problems manifest by some children may not carry over to adolescence. Changes in family and parenting practices, as well as in children's capacity to appraise and cope with family violence may help mitigate the adverse effects of family violence. 相似文献
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Eva Brumberger 《Technical Communication Quarterly》2013,22(4):369-395
This article reports the results of a survey of professional writers about the nature and importance of visual communication in their work. The results confirm the suggestions in the field's literature that visual communication is important to workplace practice and that the role of the professional writer has expanded beyond the domain of the verbal. Visual communication responsibilities are complex and varied, but the practitioners surveyed typically engage in substantial amounts of design-related work and value visual communication abilities. The data suggest that visual communication should be a curricular priority in professional writing programs. 相似文献
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Pete Goldschmidt Jose Felipe Martinez David Niemi Eva L. Baker 《Educational Assessment》2013,18(3-4):239-266
In this article we examine empirical evidence on the criterion, predictive, transfer, and fairness aspects of validity of a large-scale language arts performance assessment, referred to as the Performance Assignment (PA). We use multilevel models to avoid biased inferences that might result from the naturally nested data. Specifically, we examine the relationships of the assessment with the Stanford Achievement Test, 9th Edition and the California High School Exit Examination. The results indicate that the measures are related, that students demonstrate a degree of transfer, and that the language arts PA is relatively more fair than comparison assessments. The results are robust to various model specifications and demonstrate that benefits do not accrue to all students equally. 相似文献
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Eva M. Zygmunt‐Fillwalk 《Journal of Early Childhood Teacher Education》2013,34(2):203-204
Brain Research and Childhood Education: Implications for Educators D. Bergen and J. Coscia; Olney, MD: 2001 Association for Childhood Education International. 80 pp. ISBN 0–87173–154–1 (pbk.) 相似文献