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171.
Thomas P. Brennan Pendar Ardalan Han‐Bo‐Ram Lee Jonathan R. Bakke I‐Kang Ding Michael D. McGehee Stacey F. Bent 《Liver Transplantation》2011,1(6):1169-1175
Functioning quantum dot (QD) sensitized solar cells have been fabricated using the vacuum deposition technique atomic layer deposition (ALD). Utilizing the incubation period of CdS growth by ALD on TiO2, we are able to grow QDs of adjustable size which act as sensitizers for solid‐state QD‐sensitized solar cells (ssQDSSC). The size of QDs, studied with transmission electron microscopy (TEM), varied with the number of ALD cycles from 1‐10 nm. Photovoltaic devices with the QDs were fabricated and characterized using a ssQDSSC device architecture with 2,2',7,7'‐tetrakis‐(N,N‐di‐p methoxyphenylamine) 9,9'‐spirobifluorene (spiro‐OMeTAD) as the solid‐state hole conductor. The ALD approach described here can be applied to fabrication of quantum‐confined structures for a variety of applications, including solar electricity and solar fuels. Because ALD provides the ability to deposit many materials in very high aspect ratio substrates, this work introduces a strategy by which material and optical properties of QD sensitizers may be adjusted not only by the size of the particles but also in the future by the composition. 相似文献
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Nalini Santanam MingQing Song Rong Rong Ana A. Murphy Sampath Parthasarathy 《Free radical research》2013,47(12):1315-1321
Endometriosis affects younger women of childbearing age. Atherosclerosis is considered as a disease of the old and increases with the ageing process. Both diseases are characterized by the increased presence of activated macrophages and associated increases in growth promoting activity and the production of inflammatory cytokines. In this review, we propose that oxidative stress and the presence of forms of oxidized low-density lipoprotein (LDL) might contribute to both Atherosclerosis and Endometriosis. 相似文献
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Khare SD Kipnis Y Greisen P Takeuchi R Ashani Y Goldsmith M Song Y Gallaher JL Silman I Leader H Sussman JL Stoddard BL Tawfik DS Baker D 《Nature chemical biology》2012,8(3):294-300
The ability to redesign enzymes to catalyze noncognate chemical transformations would have wide-ranging applications. We developed a computational method for repurposing the reactivity of metalloenzyme active site functional groups to catalyze new reactions. Using this method, we engineered a zinc-containing mouse adenosine deaminase to catalyze the hydrolysis of a model organophosphate with a catalytic efficiency (k(cat)/K(m)) of ~10(4) M(-1) s(-1) after directed evolution. In the high-resolution crystal structure of the enzyme, all but one of the designed residues adopt the designed conformation. The designed enzyme efficiently catalyzes the hydrolysis of the R(P) isomer of a coumarinyl analog of the nerve agent cyclosarin, and it shows marked substrate selectivity for coumarinyl leaving groups. Computational redesign of native enzyme active sites complements directed evolution methods and offers a general approach for exploring their untapped catalytic potential for new reactivities. 相似文献
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Hyun Koo Kim Moon Sun Ham Jong Soo Hong Jin Ha Lee Kyung Yu Park Hyeon Yong Lee 《Biotechnology and Bioprocess Engineering》1996,1(1):32-35
A moving aeration-membrane (MAM) bioreactor was employed for the production of 2 μg/mL of tissue type Plasminogen Activator (tPA) in serum free medium from normal human fibroblast cells. This system could maintain high cell density for long periods of steady state conditions in perfusion cultivation. Under normal operating conditions, shear stress was as low as 0.65 dynes/cm2 at the agitation speed of 80 rpm. Even though cell density gradually decreased with increasing agitation speed, tPA production increased linearly with increasing shear stress within a moderate range. This culture system allowed production of 2 μg tPA/mL while maintaining a high cell density of 1.0×107 viable cells/mL. 相似文献
180.
Bae JS Cheong HS Kim JH Park BL Kim JH Park TJ Kim JY Pasaje CF Lee JS Park YJ Park M Park C Koh I Chung YJ Lee JY Shin HD 《PloS one》2011,6(4):e19091