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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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Dylan Poulsen Michael Defoort Mohamed Djemai 《Journal of The Franklin Institute》2019,356(16):9076-9094
We consider the leader–follower consensus problem for a multi-agent system where information is exchanged only on a non-uniform discrete stochastic time domain. For a second-order multi-agent system subject to intermittent information exchange, we model the tracking error dynamics as a varying linear system on a discrete stochastic time scale, where μ is the graininess operator. Based on a Lyapunov operator and a positive perturbation operator on the space of symmetric matrices, we derive necessary and sufficient conditions to design a decentralized consensus protocol. This protocol allows us to cast the mean-square exponential consensus problem within the framework of dynamic equations on stochastic time scales. We establish some theoretical results which allow for the computation of the control gain matrix which guarantees the mean-square exponential stability with a given decay rate for the error dynamics. To show the effectiveness of the theoretical results, some simulation and experimental results on multi-robot systems have been performed. 相似文献
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Extramural funding to support communication research influences and is influenced by the culture of our discipline, universities, and departments. Both the National Communication Association and the International Communication Association have established closer ties to funding agencies and encouraged members' grant writing pursuits through mentorship and convention programs, newsletter columns, and publicity. Universities vary in how much support they have available as infrastructure to assist in the submission and administration of grants. Some institutions facilitate extramural funding endeavors through mentoring programs, university-wide research centers, sharing of indirect costs, and space. Department cultures, too, vary in the resources available to support grants. Departments in many ways have the most direct effects on grant-supporting cultures. In addition to activities indicated for the discipline and university, departments can build a grant culture by recognizing grant writing in their personnel practices, creating systems for rewarding and supporting grant activities, and having policies in place for the many related issues (e.g., release time, indirect cost sharing, research assistants). Finally, the interpersonal culture, whether colleagues recognize and support grants, plays a major role in individual pursuit of, and satisfaction with, seeking extramural funding to support communication research. 相似文献
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Abstract: Gestures may provide the long sought‐for bridge between science laboratory experiences and scientific discourse about abstract entities. In this article, we present our results of analyzing students' gestures and scientific discourse by supporting three assertions about the relationship between laboratory experiences, gestures, and scientific discourse: (1) gestures arise from the experiences in the phenomenal world, most frequently express scientific content before students master discourse, and allow students to construct complex explanations by lowering the cognitive load; (2) gestures provide a medium on which the development of scientific discourse can piggyback; and (3) gestures provide the material that “glues” layers of perceptually accessible entities and abstract concepts. Our work has important implications for laboratory experiments which students should attempt to explain while still in the lab rather than afterwards and away from the materials. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 38: 103–136, 2001 相似文献
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In this paper, we focus on the potential innovative benefits to corporate venture capital (CVC), i.e. equity investments in entrepreneurial ventures by incumbent firms. We propose that corporate venture capital programs may be instrumental in harvesting innovations from entrepreneurial ventures and thus an important part of a firm's overall innovation strategy. We hypothesize that these programs are especially effective in weak intellectual property (IP) regimes and when the firm has sufficient absorptive capacity. We analyze a large panel of public firms over a 20-year period and find that increases in corporate venture capital investments are associated with subsequent increases in firm patenting. 相似文献
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