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941.
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
942.
943.
题目:一种支持产品平台设计的多准则模块划分方法 总被引:2,自引:0,他引:2
目的:研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法:采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品模块划分结果。结论:通过改进的多目标进化算法求解多准则模块划分模型,能够得到有效支持产品平台设计的产品模块划分方案。通过与已有优化方法的比较验证了本文提出的多准则模块划分方法的优越性。 相似文献
944.
Gloria García González 《Media History》2015,21(4):412-425
The Spanish Service was established in June 1939, two months after the end of the civil war in Spain and shortly before the start of the Second World War. Its implementation was strongly affected by these conflicts in the context of new international relations. Therefore, this study of the Spanish Service during 1939–1945 allows not only a better understanding of the communicational strategies developed by the BBC, but also of the complex Anglo-Spanish relations and the important role played by the Spanish-language broadcasts therein. The study is mainly based on archival documents from the National Archives in London and memoirs. 相似文献
945.
Maria C. Porcal-Gonzalo 《Journal of Map & Geography Libraries》2015,11(3):289-329
In recent years, there has been a growing recognition of the fact that the proper management of information has to include concern for its preservation and future re-use. This ambition is particularly significant for geospatial data. The primary aim of this article is to define the European and Spanish frameworks for the preservation and reutilization of geographical information, with the ultimate goal of proposing an articulated, lifecycle-based data management model. With this, the intent is to shed some light on a complex, difficult and ever-evolving subject.The article is divided into two main parts. The first part begins with a conceptual justification for geospatial data management and continues by synthesizing the current normative and technological framework for the preservation and reutilization of geographical information. Within this context, the implementation of Spatial Data Infrastructures (SDI) in Spain is evaluated. The second part begins with a case study from Spain that aims to identify different agents and flows that influence the lifecycle of geographical data, as well as the strengths and weaknesses found in each stage of the process under examination. Finally, the foregoing ideas are used in order to propose a SDI-related system for the management of geographical information. 相似文献
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948.
Leonardo Madariaga Miguel Nussbaum Faustino Marañón Cristóbal Alarcón María Alicia Naranjo 《Government Information Quarterly》2019,36(2):179-195
People still use documents in many everyday government processes. From tax payments to passport requests, citizens have to interact with low-interactivity information artifacts such as reports, maps and datasets, among many others. Despite efforts to improve information delivery in the public sector, effective information usage remains a critical topic of action and research. The user experience of government documents has rarely been assessed, despite them being regularly published and frequently used. Considering this, the two following research questions arise: 1) How can government documents be classified (or grouped) in terms of user experience? 2) How can the user experience of government documents be monitored over time in order to inform design decisions? Working with a public agency in Chile, we develop and test a classification and monitoring framework based on two online surveys (N?=?338 and N?=?298). We then propose a framework for understanding user experience of government documents in these three dimensions: interaction goal, volume of information and ease of understanding. Using a graphical representation to classify user experience provides greater visibility of the current status of information produced by a public organization. Furthermore, by monitoring the user experience of a government document at different times, organizations can understand the effect of their design decisions and improve their service quality by implementing user-centered processes. 相似文献
949.
Méndez A Pérez C Montañéz JC Martínez G Aguilar CN 《Journal of Zhejiang University. Science. B》2011,12(12):961-968
The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture
of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature
levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and
a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining
natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L). 相似文献
950.