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81.
For a two-dimensional potential of intersecting parabolic bowls, we obtain an analytical approximation for the survival probability in the limit that the reactive mode is diffusive and the perpendicular protein mode frozen. The approximation is used in an automated computer algorithm for determining the parameters of the potential. Using this program, we are able to obtain a reasonably good fit to the low- temperature data of CO binding to horse myoglobin. We find, however, that features of the potential such as the saddle-point energy and the effective barrier, expected to dictate the high-temperature kinetics, are not uniquely determined for this potential from fitting the low-temperature data. 相似文献
82.
Vakil Eli; Arbell Nurit; Gozlan Michal; Hoofien Dan; Blachstein Haya 《Canadian Metallurgical Quarterly》1992,60(5):802
Applied qualitative analysis to the information recalled by control Ss and closed-head-injured (CHI) patients. The Logical Memory subtest of the Wechsler Memory Scale (WMS) was administered to 40 CHI and 40 control Ss. Recall was tested immediately after administration, 40 min later, and 24 hrs later. The analysis took into account the importance of recalled information as determined by a prior rating according to 3 levels of importance. Results suggest that CHI patients have difficulty selectively retrieving the most important information after a long delay. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
采用UV - 91 0 0型紫外可见分光光度计 ,测定了由植物油脂制得的共轭亚油酸、共轭亚油酸甲酯、共轭亚油酸三甘酯在不同浓度时在 2 0 0nm - 30 0nm的吸光度 ,绘制出样品在不同浓度时的吸光度曲线 ,找出适宜的浓度范围 ,用MicrocalSoftwareOriginVersion 4.0做回归分析 ,由线性回归给出样品浓度和吸光度的线性关系 ,为对实验结果进行检验和校正 ,采用惠普 845 2A二极管阵列分光光度计测定了同一批样品在不同浓度范围内的吸光度 ,利用PEAutosystemXL -TurboMass测得样品中共轭亚油酸准确浓度 ,结合回归系数给出了用紫外可见分光光度计快速测定样品中共轭亚油酸含量的经验公式 相似文献
84.
Eli Pollak 《Israel journal of chemistry》1989,29(4):355-359
The normal mode transformation of the Hamiltonian equivalent of the Generalized Langevin Equation for the free particle is used to provide explicit solutions for the classical and quantum-mechanical diffusion of a free particle. 相似文献
85.
Rats with complete surgical removal of the neocortex (neodecorticates) were trained, with milk as the reinforcer, on a 40-sec fixed-interval (FI-40) schedule, then on an FI-120, and finally reexposed to the FI-40. Like controls, neodecorticates developed and appropriately adjusted their postreinforcement pauses and response distributions and showed scallop-type responding on the FI-120 and a positive correlation between running rate and the preceding postreinforcement pause on both FI-40 schedules but not on the FI-120. On some variables neodecorticates reached asymptotic levels of performance more slowly than controls. Extended training on the first FI-40 did not differentially affect neodecorticates' performance. The results suggest that neodecorticates retain a functional timing mechanism. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Functional Chromatography Reveals Three Natural Products that Target the Same Protein with Distinct Mechanisms of Action
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Dr. Min Jin Kang Dr. Tongde Wu Dr. E. M. Kithsiri Wijeratne Eric C. Lau Damian J. Mason Celestina Mesa Joseph Tillotson Prof. Dr. Donna D. Zhang Prof. Dr. A. A. Leslie Gunatilaka Dr. James J. La Clair Prof. Dr. Eli Chapman 《Chembiochem : a European journal of chemical biology》2014,15(14):2125-2131
Access to lead compounds with defined molecular targets continues to be a barrier to the translation of natural product resources. As a solution, we developed a system that uses discrete, recombinant proteins as the vehicles for natural product isolation. Here, we describe the use of this functional chromatographic method to identify natural products that bind to the AAA+ chaperone, p97, a promising cancer target. Application of this method to a panel of fungal and plant extracts identified rheoemodin, 1‐hydroxydehydroherbarin, and phomapyrrolidone A as distinct p97 modulators. Excitingly, each of these molecules displayed a unique mechanism of p97 modulation. This discovery provides strong support for the application of functional chromatography to the discovery of protein modulators that would likely escape traditional high‐throughput or phenotypic screening platforms. 相似文献
87.
Johannes Staguhn Dominic Benford Eli Dwek Gene Hilton Dale Fixsen Kent Irwin Christine Jhabvala Attila Kovacs Samuel Leclercq Stephen Maher Tim Miller S. Harvey Moseley Elmer Sharp Edward Wollack 《Journal of Low Temperature Physics》2014,176(5-6):829-834
We present the main design features for the GISMO-2 bolometer camera, which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISMO-2 will operate simultaneously in the 1 and 2 mm atmospherical windows. The 1 mm channel uses a \(32 \times 40\) TES-based backshort under grid (BUG) bolometer array, the 2 mm channel operates with a \(16 \times 16\) BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISMO-2 was strongly influenced by our experience with the GISMO 2 mm bolometer camera, which is successfully operating at the 30 m telescope. GISMO is accessible to the astronomical community through the regular IRAM call for proposals. 相似文献
88.
We present a comprehensive robot development process and its evaluation. We designed this process in the context of a robotics course in high schools. The motivation for designing this new process was improving the robustness and reliability of robots developed by students and preparing students for becoming better designers. The newly designed process proved to be highly successful in designing top quality robots. In the process design, we explored and adapted existing design tools and methods to the specific designers, the nature of the product, the environment, the product needs, and the design context goals. At the end of this thorough design, we selected a synergetic integration of six tools and methods to compose the new comprehensive development process for this product context: conceptual design, fault-tolerant design, atomic requirements, fuzzy logic for control, creative thinking, and microprogramming-based design. The design skills of the students that learned the design process and the performance of robots they designed and participated in an international robotics contest were examined. The high school teams that studied the proposed process won the first places in an international contest. The robots developed by the students had better performance than robots built by engineers and faculty teams. Professional experts rated the robots’ designs as excellent. The students that studied the process demonstrated high level of diverse design skills including creativity and design management capabilities. Additionally, they improved their science subject grades and their attitude toward engineering. Both the results obtained by the study and the authors’ experience in teaching robotics demonstrate that the proposed robot development process could be taught successfully in high school and that it leads to superior robotic products. Our experience also indicates that this process could serve industry design by improving the robustness of robots operating in uncertain environments and supporting fast change management practices. 相似文献
89.
90.
Eliaz N Ritman-Hertz O Aronov D Weinberg E Shenhar Y Rosenman G Weinreb M Ron E 《Journal of materials science. Materials in medicine》2011,22(7):1741-1752
The effect of different mechanical and chemical pre-treatments on the adhesion strength of hydroxyapatite (HAp) coating on
a commercially pure titanium (CP-Ti) substrate was studied by means of a standard tensile test followed by microscopic and
chemical analysis to determine the locus of fracture. In addition, the effects of either these pre-treatments or post-treatment
by low-energy electron irradiation, which allowed tuning the wettability of the surface, on both osteoblast progenitor attachment
and S. aureus bacteria attachment were investigated. A dedicated program was developed for unambiguous identification and count of stained
cells. A single-phase HAp coating was formed by electrodeposition. A series of surface pre-treatments consisted of grinding
down to P1000, etching in HNO3/HF solution, grit blast, soaking in NaOH and subsequent heat treatment provided the highest adhesion strength to the HAp
coating. Osteoblast progenitors derived from rats may be attached preferentially to a hydrophilic surface (post-treatment
to θ = 30°), while the bacteria seemed to be less attached to hydrophobic surfaces (post-treatment to θ = 105°). However, the results were not statistically different. The bacteria seemed to be less attached to the smoother,
uncoated surfaces. 相似文献