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61.
62.
Herbert J. Gans Robert A. Dentler Paul Davidoff 《Journal of the American Planning Association. American Planning Association》2013,79(3):189-193
This study develops a research method of assessing people's satisfaction with housing. Instead of the old approaches which consider in fragmented ways the characteristics of the dwelling, or the neighborhood, or the social environment, the author proposes a systems approach in which various interdependent factors are studied in relation to one another. Using the techniques developed, the relative satisfaction of tenants in public housing projects in certain areas of Canada is identified, analyzed, and discussed. 相似文献
63.
S. Herbert Hare Sir Raymond Unwin 《Journal of the American Planning Association. American Planning Association》2013,79(1):20-22
When We Build Again. A Bournville Village Trust Research Publication. George Allen &; Unwin, Ltd., London, 1941. Pp. xii (16), 138. Report Relative to Postwar Reconstruction in the City, Prepared by Improvements and Town Planning Committee, published by The Corporation of London, 1944, pp. 66 plus maps and photographs. The Economic Status of the New York Metropolitan Region in 1944, by The Regional Plan Association, Inc., New York, 1944, xx, 91 pp. 相似文献
64.
65.
Hanna Mannell Petra Kameritsch Heike Beck Alexander Pfeifer Ulrich Pohl Kristin Pogoda 《International journal of molecular sciences》2022,23(1)
The gap junction protein connexin 43 (Cx43) is associated with increased cell migration and to related changes of the actin cytoskeleton, which is mediated via its C-terminal cytoplasmic tail and is independent of its channel function. Cx43 has been shown to possess an angiogenic potential, however, the role of Cx43 in endothelial cell migration has not yet been investigated. Here, we found that the knock-down of Cx43 by siRNA in human microvascular endothelial cells (HMEC) reduces migration, as assessed by a wound assay in vitro and impaired aortic vessel sprouting ex vivo. Immunoprecipitation of Cx43 revealed an interaction with the tyrosine phosphatase SHP-2, which enhanced its phosphatase activity, as observed in Cx43 expressing HeLa cells compared to cells treated with an empty vector. Interestingly, the expression of a dominant negative substrate trapping mutant SHP-2 (CS) in HMEC, via lentiviral transduction, also impaired endothelial migration to a similar extent as Cx43 siRNA compared to SHP-2 WT. Moreover, the reduction in endothelial migration upon Cx43 siRNA could not be rescued by the introduction of a constitutively active SHP-2 construct (EA). Our data demonstrate that Cx43 and SHP-2 mediate endothelial cell migration, revealing a novel interaction between Cx43 and SHP-2, which is essential for this process. 相似文献
66.
Guillaume R. Durand Quentin Bizot Nathalie Herbert Samuel Quéméré Mathieu Pasturel Xiang-Hua Zhang Odile Merdrignac-Conanec 《Journal of the American Ceramic Society》2020,103(4):2328-2339
The densification of CaLa2S4 (CLS) powders prepared by combustion method was investigated by the use of Field-Assisted Sintering Technique (FAST) and Hot Pressing (HP). CLS powders were sintered using FAST at 1000°C at different pressures and heating rates and sintered by HP under 120 MPa from 800°C to 1100°C for 6 hours with a heating rate of 10°C/min. Comparison of both techniques was further realized by use of the same conditions of pressure, dwell time, and heating rate. Complementary techniques (XRD, SEM-EDS, density measurements, FTIR spectroscopy) were employed to correlate the sintering processes/parameters to the microstructural/compositional developments and optical transmission of the ceramics. Both sintering techniques produce ceramics with submicrometer grain size and relative density of about 99%. Nevertheless, HP is more suitable to densify CLS ceramics without fragmentation and also reach higher transmission than FAST. Transmission of 40%–45% was measured out of a possible maximum of 69% based on the Fresnel losses in the 8-14 μm window when HP is applied at 1000°C for 6 hours under 120 MPa. In both techniques, ceramics undergo reduction issues that originate from graphitic sintering atmosphere. 相似文献
67.
Dieter Grschl Axel Mayer Michael Schmidt Herbert Meier 《Advanced Synthesis \u0026amp; Catalysis》1995,337(1):379-384
Synthesis of Benzo[b]thioxanthenes Benzo[b]thioxanthenes, heterocyclic compounds related to tetracenes and tetracyclines can be obtained by the reaction of 2H-benzo[b]thiete ( 1 ) and 1,4-naphthoquinones ( 3a–g ). The primary cycloadducts 4a–g undergo an autoxidation process leading to the quinones 6a–g . The dihydroxy compound 4e shows an additional isomerization by a tetrafold H transfer ( 4e → 5e ′). Another preparative route to benzo[b]thioxanthenes makes use of the cycloadditon reaction of 1 and 1,4-epoxynaphthalenes ( 7a–d ). The primary adducts can be transformed to the title compounds by catalytic dehydration processes ( 8a–d → 9a-d ). An alternate regioselective opening of the oxygen bridge can be performed by the action of trimethyliodosilane ( 8a → 10a ). Methylation of 9a furnishes the sulfonium salt 14a which rearranges in a strongly alkaline medium to 16a ; in the presence of oxygen ketone 17a is generated. 相似文献
68.
69.
By autoclaving a watery high amylose corn starch suspension, homogenous and isotrope films were obtained with different processing parameters. The films were used for investigations on the stress strain behavior. A systematical dependence on the water content and the relationship between native lipids and the starch chains was observed. Especially for films obtained from defatted corn starch, a clear transition was obtained, depending on the water content, from a brittle behavior far below the glass transition temperature TG with a very high Youngsmodulus to a ductile failure behavior above TG. The results led to a microscopical model for the native high amylose corn starch films, which in addition outlines the very interesting possibility of controlling in detail changes of the macroscopic stress strain behavior through variations on a molecular scale. 相似文献
70.
Karlheinz Drauz Matthias Kottenhahn Herbert Klenk 《Advanced Synthesis \u0026amp; Catalysis》1992,334(3):214-218
Chemoenzymatical Synthesis of N6-Carbamoyl-D-4-thialysine and N7-Carbamoyl-D-homo-5-thialysine The combination of classical chemical and enzymatical methods opens a way to highly functionalized chiral molecules like N6-carbamoyl-D-4-thialysine ( 5 ) or N7-carbamoyl-D-homo-5-thialysine ( 6 ). The biotransformation of the corresponding hydantoines with Agrobacterium radiobacter is creating the desired D chirality. 相似文献