868 research outputs found
Interview with Florence Campbell Kloxin
An interview with former teacher Florence Campbell Kloxin regarding her experiences in a one-room school house.https://scholars.fhsu.edu/ors/1034/thumbnail.jp
Longitudinal Spatial Dynamics of Pelagial Fish and Planktonic Assemblages in Tenkiller Ferry Lake
Click Chemistry in Materials Science
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106803/1/adfm201302847.pd
Dual Photosensitive Polymers with Wavelength-Selective Photoresponse
Polyurethane thin films that photopolymerize and photodegrade upon exposure to light of different wavelengths are presented. The chromic response is based on two caged monomers with the ability to be activated or photocleaved with different wavelengths under single and two-photon excitation. This material represents a dual photoresist with "positive" and "negative" tone contained in a single resist formulation and with the ability to generate complex 2D and 3D patterns.The authors thank the DFG-ANR bilateral funding program for financial support (ANR- 09-BLAN-0426–01 and DFG CA880/3–1). Andreas Best, Dr. K. Koynov and Dr. F. Laquai (MPIP Mainz) are gratefully acknowledged for their help with the two-photon exposure
Mechanotransduction and growth factor signalling to engineer cellular microenvironments
Engineering cellular microenvironments involves biochemical factors, the extracellular matrix (ECM) and the interaction with neighbouring cells. This progress report provides a critical overview of key studies that incorporate growth factor (GF) signalling and mechanotransduction into the design of advanced microenvironments. Materials systems have been developed for surface-bound presentation of GFs, either covalently tethered or sequestered through physico-chemical affinity to the matrix, as an alternative to soluble GFs. Furthermore, some materials contain both GF and integrin binding regions and thereby enable synergistic signalling between the two. Mechanotransduction refers to the ability of the cells to sense physical properties of the ECM and to transduce them into biochemical signals. Various aspects of the physics of the ECM, i.e. stiffness, geometry and ligand spacing, as well as time-dependent properties, such as matrix stiffening, degradability, viscoelasticity, surface mobility as well as spatial patterns and gradients of physical cues are discussed. To conclude, various examples illustrate the potential for cooperative signalling of growth factors and the physical properties of the microenvironment for potential applications in regenerative medicine, cancer research and drug testing
Reversible click chemistry at the service of macromolecular materials
The application of the reversible Diels-Alder (DA) reaction to the realm of furan polymers has recently bloomed, because of its potential for the preparation of a wide variety of novel macromolecular materials based on renewable resources, possessing, among other properties, thermoreversible, mendable and recycling features. In this study, the synthesis and characterisation of novel furan-maleimide monomers, viz. AB-type molecules, and their polycondensation by means of the DA reaction, are presented. These systems represent an interesting alternative to the traditional linear DA polycondensations, because they ensure the ideal initial stoichiometry. The behaviour of two A-B monomers was investigated with the maleimide group protected in the form of a furan-DA adduct in order to obtain a stable monomer and thus avoid premature polymerization. Their polycondensation was then followed after the in situ deprotection at high temperature, followed by the cooling to the appropriate temperature for the DA polymerization to occur.FCT - SFRH/BD/ 28271/2006REEQ/515/CTM/2005POCI 2010FEDE
Photodegradable, Photoadaptable Hydrogels via Radical-Mediated Disulfide Fragmentation Reaction
3D Electrophoresis-Assisted Lithography (3DEAL): 3D Molecular Printing to Create Functional Patterns and Anisotropic Hydrogels
Photopolymerization as a promising method to sense biorecognition events
[EN] This work addresses the main topics related to the photopolymerization process to develop and to monitor the analytical signal derived from biorecognition assays. We review basic aspects of photopolymerization, together with the nature and the reactivity of the chemicals involved. Focusing on DNA and protein determination and medical applications, we envisage as relevant photopolymers that generate biocompatible hydrogels. We also review the major characterization techniques applied to ascertain the composition of the products formed and to monitor the progress of the reaction. In this sense, we present optical microscopy, fluorescence imaging, ATR-FTIR spectroscopy and profilometry measures.Finally, we discuss analytical examples and applications of protein-to-protein, protein-to-antigen and DNA-hybridization photopolymerization. We demonstrate implementation of CD/DVD player technology to the detection and quantitation of such biointeractions, highlighting the advantages of this powerful methodology in biosensing. © 2012 Elsevier Ltd.This work was funded by the projects FEDER CTQ2010-15943 (CICYT, Spain), PROMETEO 2010/008 (Generalitat Valenciana), and interdisciplinary UPV PAID 05 - 10 grant.Peris Chanzá, EJ.; Bañuls Polo, M.; Maquieira Catala, Á.; Puchades, R. (2012). Photopolymerization as a promising method to sense biorecognition events. Trends in Analytical Chemistry. 41:86-104. https://doi.org/10.1016/j.trac.2012.09.003S861044
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