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Extracellular matrix (ECM) is an essential and dynamic component of all tissues and directly affects cellular behavior by providing both mechanical and biochemical signaling cues. Changes in ECM can alter tissue homeostasis, potentially leading to promotion of cellular transformation and the generation of tumors. Therefore, understanding ECM compositional changes during cancer progression is vital to the development of targeted treatments. Previous efforts to reproduce the native 3D cellular microenvironment have utilized protein gels and scaffolds that incompletely recapitulate the complexity of native tissues. Here, we address this problem by extracting and comparing ECM from normal human colon and colon tumor that had metastasized to liver. We found differences in protein composition and stiffness, and observed significant differences in vascular network formation and tumor growth in each of the reconstituted matrices, both in vitro and in vivo. We studied free/bound ratios of NADH in the tumor and endothelial cells using Fluorescence Lifetime Imaging Microscopy as a surrogate for the metabolic state of the cells. We observed that cells seeded in tumor ECM had higher relative levels of free NADH, consistent with a higher glycolytic rate, than those seeded in normal ECM. These results demonstrate that the ECM plays an important role in the growth of cancer cells and their associated vasculature.

In this paper, we explain how presidents strategically invest in administrative capacity, noting that presidents have few incentives to invest effort in capacity building in most agencies. We test our account with two analyses. First, we examine the time it took for the Bush, Obama, Trump, and Biden Administrations to nominate individuals to appointed positions. We find that presidents prioritize appointments to policy over management positions and that nominations occur sooner in agencies that implement presidential priorities. Second, we examine the responses of federal executives to the 2020 Survey on the Future of Government Service to see whether perceptions of presidential investment in administrative capacity match our predictions. We find that federal executives perceive higher levels of investment when the agency is a priority of the president and when the agency shares the president's policy views. We conclude with implications for our understanding of the modern presidency and government performance. [ABSTRACT FROM AUTHOR]

"Molecular World: Making Modern Chemistry" by Catherine M. Jackson is a book that explores the development of organic chemistry through empirical observations in the laboratory. The book is divided into three sections, focusing on the work of Justus Liebig, August Wilhelm Hofmann, and Albert Ladenburg. It discusses the impact of Liebig's Kaliapparat device on organic analysis and the financial challenges faced by Liebig. The book also highlights Hofmann's experimental work and his development of new reactions of amines with alkyl halides. While the author's arguments about the role of theory in organic chemistry are not entirely convincing, the book offers a thought-provoking perspective on the subject. [Extracted from the article]