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排序方式: 共有2523条查询结果,搜索用时 15 毫秒
1.
Chinh Ngo Radhika Mehta Kanchan Aggarwal Audrey G. Fikes Dr. Ines C. Santos Dr. Sylvester M. Greer Prof. Dr. Emily L. Que 《Chembiochem : a European journal of chemical biology》2019,20(8):1003-1007
One-third of all proteins are estimated to require metals for structural stability and/or catalytic activity. Desthiobiotin probes containing metal binding groups can be used to capture metalloproteins with exposed active-site metals under mild conditions so as to prevent changes in metallation state. The proof-of-concept was demonstrated with carbonic anhydrase (CA), an open active site, Zn2+-containing protein. CA was targeted by using sulfonamide derivatives. Linkers of various lengths and structures were screened to determine the optimal structure for capture of the native protein. The optimized probes could selectively pull down CA from red blood cell lysate and other protein mixtures. Pull-down of differently metallated CAs was also investigated. 相似文献
2.
Robust backward adaptive formant prediction for speech coder 总被引:1,自引:0,他引:1
To improve the error performance of speech coders, an adaptation method for the backward adapted formant predictor is proposed. The filtered residual signal is used instead of the reconstructed output signal as the input to an adaptation of the formant predictor. The performance of the filtered-residual driven adaption method in the noise free channel is as good as that of conventional output driven adaptation. Moreover, the new adaptation method maintains the same robustness to channel errors as residual driven adaptation 相似文献
3.
C. W. Draper J. M. Gibson D. C. Jacobson J. M. Poate S. M. Shin J. M. Rigsbee 《Journal of Materials Science》1985,20(7):2303-2312
Evaporated thin tantalum films on single and polycrystalline nickel have been laser surface alloyed using either continuous-wave CO2 or Q-switched Nd-YAG radiation. In the case of the continuous-wave laser, surface alloys contain amorphous tantalum-rich regions, intermediate polycrystalline bands of TaNi, and an underlying Ni(Ta) solid solution. In the Q-switched laser case, a much more laterally uniform amorphous phase with approximately equal atomic fractions of nickel and tantalum is found, with little evidence of polycrystalline intermetallics.In situ annealing with the electron beam of the microscope results in formation of microcrystallites, predominantly nickel. 相似文献
4.
Butler Emily A.; Egloff Boris; Wlhelm Frank H.; Smith Nancy C.; Erickson Elizabeth A.; Gross James J. 《Canadian Metallurgical Quarterly》2003,3(1):48
At times, people keep their emotions from showing during social interactions. The authors' analysis suggests that such expressive suppression should disrupt communication and increase stress levels. To test this hypothesis, the authors conducted 2 studies in which unacquainted pairs of women discussed an upsetting topic. In Study 1, one member of each pair was randomly assigned to (a) suppress her emotional behavior, (b) respond naturally, or (c) cognitively reappraise in a way that reduced emotional responding. Suppression alone disrupted communication and magnified blood pressure responses in the suppressors' partners. In Study 2, suppression had a negative impact on the regulators' emotional experience and increased blood pressure in both regulators and their partners. Suppression also reduced rapport and inhibited relationship formation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Sheldon "Shep" Harold White, one of developmental psychology's most distinguished scholars, died on March 17, 2005, at the age of 76. He is perhaps best remembered for his sharp intellect, generous spirit, good humor, and warm compassion. Shep's principal work lay in three intermeshed areas: children's learning and cognitive development, social programs and policies, and the history of developmental psychology. Shep White is sorely missed by his family and friends, and countless children have unknowingly benefited from his research, scholarship, and contributions to public policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Emily S. Patterson David D. Woods Richard I. Cook Marta L. Render 《Cognition, Technology & Work》2007,9(3):155-162
Resilience, the ability to adapt or absorb disturbance, disruption, and change, may be increased by team processes in a complex,
socio-technical system. In particular, collaborative cross-checking is a strategy where at least two individuals or groups
with different perspectives examine the others’ assumptions and/or actions to assess validity or accuracy. With this strategy,
erroneous assessments or actions can be detected quickly enough to mitigate or eliminate negative consequences. In this paper,
we seek to add to the understanding of the elements that are needed in effective cross-checking and the limitations of the
strategy. We define collaborative cross-checking, describe in detail three healthcare incidents where collaborative cross-checks
played a key role, and discuss the implications of emerging patterns. 相似文献
7.
The Metaflow architecture, a unified approach to maximizing the performance of superscalar microprocessors, is introduced. The Metaflow architecture exploits inherent instruction-level parallelism in conventional sequential programs by hardware means, without relying on optimizing compilers. It is based on a unified structure, the DRIS (deferred-scheduling, register-renaming instruction shelf), that manages out-of-order execution and most of the attendant problems. Coupling the DRIS with a speculative-execution mechanism that avoids conditional branch stalls results in performance limited only be inherent instruction-level parallelism and available execution resources. Although presented in the context of superscalar machines, the technique is equally applicable to a superpipelined implementation. Lightning, the first implementation of the Metaflow architecture, which executes the Sparc RISC instruction set is described 相似文献
8.
Jaakkola Kelly; Fellner Wendi; Erb Linda; Rodriguez Mandy; Guarino Emily 《Canadian Metallurgical Quarterly》2005,119(3):296
In 2 experiments, bottlenose dolphins (Tursiops truncatus) judged the ordinal relationship between novel numerosities. The dolphins were first trained to choose the exemplar with the fewer number of items when presented with just a few specific comparisons (e.g., 2 vs. 6, 1 vs. 3, and 3 vs. 7). Generalization of this rule was then tested by presenting the dolphins with all possible pairwise comparisons between 1 and 8. The dolphins chose the exemplar with the fewer number of items at levels far above chance, showing that they could recognize and represent numerosities on an ordinal scale. Their pattern of errors was consistent with the idea of an underlying analog magnitude representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Pebbles Fagan Vickie Shavers Deirdre Lawrence James Todd Gibson Paris Ponder 《Nicotine & tobacco research》2007,9(2):241-248
Little is known about factors associated with smoking among the unemployed. This study estimated the prevalence of smoking and examined sociodemographic factors associated with current, former, and successful quitting among unemployed adults aged 18-64. Cross-sectional data on 13,480 participants in the 1998-1999 and 2001-2002 Tobacco Use Supplements to the Current Population Surveys were analyzed. Multivariate logistic regression analyses were used to examine factors associated with study outcomes (current vs. never, former vs. current, successful quitter vs. other former smoker). Among the unemployed, 35% were current smokers and 13% were former smokers. Of the former smokers, 81% quit successfully for at least 12 months. Participants with family incomes of less than US$25,000 were more likely than those with incomes of $50,000 or more to currently smoke (OR=2.13, 95% CI=1.85-2.46). Service workers and blue-collar workers were less likely than white-collar workers to report former smoking. Participants unemployed for 6 months or more were twice as likely as those unemployed for less than 6 months to quit successfully (OR=2.05, 95% CI=1.07-3.95). Unemployed blue-collar workers had a greater odds ratio of successfully quitting than white-collar workers (OR=1.83, 95% CI=1.17-2.87). Smoking rates were high among the unemployed, and quitting behaviors varied by sociodemographic factors and length of unemployment. Studies are needed to examine the feasibility of cessation interventions for the unemployed. 相似文献
10.
Gregory S. Ho Chen Huang Emily A. Carter 《Current Opinion in Solid State & Materials Science》2007,11(5-6):57-61
Orbital-free density functional theory (OF-DFT) can be made to scale linearly with sample size, allowing thousands of atoms to be treated explicitly with quantum mechanics. State-of-the-art kinetic energy density functionals and ion–electron pseudopotentials are used to obtain accurate structural property predictions for nanoparticles, nanowires, extended surfaces, and nanoindentation of simple metals. 相似文献