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991.
L. Yu S. M. Grist S. S. Nasseri E. Cheng Y.-C. E. Hwang C. Ni K. C. Cheung 《Biomicrofluidics》2015,9(2)
Creating multicellular tumor spheroids is critical for characterizing anticancer treatments since they may provide a better model of the tumor than conventional monolayer culture. Moreover, tumor cell interaction with the extracellular matrix can determine cell organization and behavior. In this work, a microfluidic system was used to form cell-laden core-shell beads which incorporate elements of the extracellular matrix and support the formation of multicellular spheroids. The bead core (comprising a mixture of alginate, collagen, and reconstituted basement membrane, with gelation by temperature control) and shell (comprising alginate hydrogel, with gelation by ionic crosslinking) were simultaneously formed through flow focusing using a cooled flow path into the microfluidic chip. During droplet gelation, the alginate acts as a fast-gelling shell which aids in preventing droplet coalescence and in maintaining spherical droplet geometry during the slower gelation of the collagen and reconstituted basement membrane components as the beads warm up. After droplet gelation, the encapsulated MCF-7 cells proliferated to form uniform spheroids when the beads contained all three components: alginate, collagen, and reconstituted basement membrane. The dose-dependent response of the MCF-7 cell tumor spheroids to two anticancer drugs, docetaxel and tamoxifen, was compared to conventional monolayer culture. 相似文献
992.
达格拉斯·贝格美 《商丘师范学院学报》2015,(2):29-33
心与身体其他感觉器官的关系问题,备受先秦两汉所有重要思想流派的争议。众所周知,传统儒家认为心是主"情"的器官,并具有分析其他感官之间差异的能力1。对于孟子来说,"四端"学说就是关于"心"的内容,最为显著的是恻隐之心,它能促进人们德性的成长2。对于儒家来说,与其他自然的感觉器官相比,"心"是较为高级的。因为它不仅具有思考的能力,而且能评估人们所遇之事;而其他感知器官,仅仅是在于接触其他事物3。"心"比其 相似文献
993.
Johanna Tevaniemi Jenni Poutanen Riitta Lähdemäki 《New Review of Academic Librarianship》2015,21(3):304-324
This article presents a case of co-designed temporary learning spaces at a Finnish academic library, together with the results of a user-survey. The experimental development of the multifunctional spaces offered an opportunity for the library to collaborate with its parent organisation thus broadening the role of the library. Hence, library can be seen as a third player facilitating learning spaces. Additionally, the library's own expertise was strengthened through successful cooperation with the undergraduate students and other actors. The results support prior research, where studying in the library is target-oriented differing from other learning spaces in providing support and resources. 相似文献
994.
Digitization has resulted in great uncertainty for journalism, leading to disruption of business models, revenue streams, media distinctions, and production practices. This uncertainty has led to many articles, reports, blog posts, and general commentary discussing the future of both journalism and the skills required by journalists to succeed in this environment. This essay analyzes these discourses, focusing specifically on the nature of technology as the sole determiner of journalism’s future, with interventions aimed at journalism education and the structure of newswork. An idealized notion of the technologically adept journalist, ready to usher in digital stability, emerges as the object of these debates and, thanks in large part to the limited scope and ahistorical character of digital discourse, obscures more persistent, systemic critiques of technology and journalism. 相似文献
995.
This paper focuses on sustainability strategies for the Forestry–Wood chain (FWC) driven by market demands on books and other products. The main objective is to draft and suggest a process for market driven pro-active sustainability strategies for the FWC, based on a SWOT-analysis (strengths, weaknesses, opportunities and threats). Further to highlight the possible strategic implications and critical areas for actors upstream in the FWC, in the context of uncertain external future scenarios. Higher demands on product differentiation were found throughout the FWC, where also collaboration and stakeholder interaction was found important to improve sustainability. The work broadens the “traditional” perspectives on FWC sustainability to encompass also interacting value chains such as book production and publishing, to get a more holistic view. 相似文献
996.
Marisa L. Conte Mark P. MacEachern Nandita S. Mani Whitney A. Townsend Judith E. Smith Chase Masters Caitlin Kelley 《Journal of the Medical Library Association》2015,103(2):69-73
Objective:The researchers used the flipped classroom model to develop and conduct a systematic review course for librarians.Setting:The research took place at an academic health sciences library.Method:A team of informationists developed and conducted a pilot course. Assessment informed changes to both course components; a second course addressed gaps in the pilot.Conclusion:The flipped classroom model can be successful in developing and implementing a course that is well rated by students. 相似文献
997.
998.
V.L.Krupenin 《出版与印刷》2015,(1)
In this paper in general the dynamic effects are considered and described, caused by different stand-ing waves in discrete and distributed systems with impacts and other strongly positional non-linear fac-tors, introduction of which in the models of me-chanical objects is dictated by the necessity to con-sider processes, accompanied with impacts of me-chanical subsystems of different nature. 相似文献
999.
用不同于已有文献的方法研究了一类高阶中立型微分方程,本文不需要条件f∞t0Q(s)ds=∞,获得了这类方程振动性的几个新的结果. 相似文献
1000.
It has previously been demonstrated that enactment (i.e., performing representative gestures during encoding) enhances memory for concrete words, in particular action words. Here, we investigate the impact of enactment on abstract word learning in a foreign language. We further ask if learning novel words with gestures facilitates sentence production. In a within‐subjects paradigm, participants first learned 32 abstract sentences from an artificial corpus conforming with Italian phonotactics. Sixteen sentences were encoded audiovisually. Another set of 16 sentences was also encoded audiovisually, but, in addition, each single word was accompanied by a symbolic gesture. Participants were trained for 6 days. Memory performance was assessed daily using different tests. The overall results support the prediction that learners have better memory for words encoded with gestures. In a transfer test, participants produced new sentences with the words they had acquired. Items encoded through gestures were used more frequently, demonstrating their enhanced accessibility in memory. The results are interpreted in terms of embodied cognition. Implications for teaching and learning are suggested. 相似文献