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101.
Diffusion rate of dye-labelled PAMAM dendrimers through free-standing silica colloidal crystals was studied as a function of the dendrimer generation and nanopore size to determine the transport selectivity. 相似文献
102.
A general method has been developed for arylation of readily available 1H-perfluoroalkanes. The method employs aryl iodide and 1H-perfluoroalkane reagents, DMPU solvent, TMP(2)Zn base, and a copper chloride/phenanthroline catalyst. Preliminary mechanistic studies are reported. 相似文献
103.
Jagadeesan D Nasimova I Gourevich I Starodubtsev S Kumacheva E 《Macromolecular bioscience》2011,11(7):889-896
A microfluidic strategy for the encapsulation and stimulus-responsive release of molecules with distinct polarities from the interior of microgels is reported. The approach relies on (i) the generation of a primary O/W emulsion by the ultrasonication method, (ii) MF emulsification of the primary emulsion, and (iii) photopolymerization of the monomer present in the aqueous phase of the droplets, thereby transforming them into microgels. Non-polar molecules are dissolved in oil droplets embedded in the microgels. Polar molecules are physically associated with the hydrogel network. Upon heating, the microgels contract and release polar and non-polar cargo molecules. The approach paves the way for stimuli-responsive vehicles for multiple drug delivery. 相似文献
104.
A discussion of proficiency testing (PT) topics started by Heydorn (Accred Qual Assur 15:643–645, 2010) is continued in the present paper. The role of PT in the accreditation of testing/analytical laboratories, the use of consensus
values (average or weighted average, median, observed standard deviation, etc.) and a metrological background of PT schemes
are discussed. It is shown that metrological traceability, comparability, and compatibility, as well as commutability of a
reference material, are the key issues of any PT scheme that applies certified reference material as test items. Metrological
compatibility of PT results in such schemes is a property demonstrating the closeness of the PT results to the certified value
in comparison with the measurement uncertainty of their difference. The metrological background is especially important for
the selection and use of PT schemes for a limited number of participants (fewer than 30) as detailed in IUPAC/CITAC Guide
on the topic published in 2010 in Pure Appl Chem 82(5):1099–1135. 相似文献
105.
Ilya Kuselman Elena Kardash Emil Bashkansky Francesca Pennecchi Stephen L. R. Ellison Karen Ginsbury Malka Epstein Aleš Fajgelj Yury Karpov 《Accreditation and quality assurance》2013,18(6):459-467
A new technique for quantification of human errors in chemical analysis using expert judgments is described. This technique is based on the house-of-security approach developed recently in the field of safety and security for prevention of terrorist and criminal attacks against an organization. The following relative quantification parameters (expressed in %) are proposed in the technique: (a) likelihood score of human error in a chemical analytical measurement/testing method, (b) severity score of human error for reliability of the test results, (c) importance score of a component of a laboratory quality system, and (d) effectiveness score of the quality system as a whole in preventing/blocking human error. As an example, 34 scenarios of human error in pH measurement of groundwater are discussed and quantified. 相似文献
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RGDS‐ and SIKVAVS‐Modified Superporous Poly(2‐hydroxyethyl methacrylate) Scaffolds for Tissue Engineering Applications 下载免费PDF全文
Hana Macková Zdeněk Plichta Vladimír Proks Ilya Kotelnikov Jan Kučka Helena Hlídková Daniel Horák Šárka Kubinová Klára Jiráková 《Macromolecular bioscience》2016,16(11):1621-1631
Three‐dimensional hydrogel supports for mesenchymal and neural stem cells (NSCs) are promising materials for tissue engineering applications such as spinal cord repair. This study involves the preparation and characterization of superporous scaffolds based on a copolymer of 2‐hydroxyethyl and 2‐aminoethyl methacrylate (HEMA and AEMA) crosslinked with ethylene dimethacrylate. Ammonium oxalate is chosen as a suitable porogen because it consists of needle‐like crystals, allowing their parallel arrangement in the polymerization mold. The amino group of AEMA is used to immobilize RGDS and SIKVAVS peptide sequences with an N‐γ‐maleimidobutyryloxy succinimide ester linker. The amount of the peptide on the scaffold is determined using 125I radiolabeled SIKVAVS. Both RGDS‐ and SIKVAVS‐modified poly(2‐hydroxyethyl methacrylate) scaffolds serve as supports for culturing human mesenchymal stem cells (MSCs) and human fetal NSCs. The RGDS sequence is found to be better for MSC and NSC proliferation and growth than SIKVAVS.
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Back Cover: GM1 Ganglioside Inhibits β‐Amyloid Oligomerization Induced by Sphingomyelin (Angew. Chem. Int. Ed. 32/2016) 下载免费PDF全文
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