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61.
Zhen EY Berna MJ Jin Z Pritt ML Watson DE Ackermann BL Hale JE 《Proteomics. Clinical applications》2007,1(7):661-671
Heart fatty acid binding protein (Fabp3) is a cytosolic protein expressed primarily in heart, and to a lesser extent in skeletal muscle, brain, and kidney. During myocardial injury, the Fabp3 level in serum is elevated rapidly, making it an ideal early marker for myocardial infarction. In this study, an MS‐based selected reaction monitoring method (LC‐SRM) was developed for quantifying Fabp3 in rat serum. Fabp3 was enriched first through an immobilized antibody, and the protein was digested on beads directly. A marker peptide of Fabp3 was quantified using LC‐SRM with a stable isotope‐labeled peptide standard. For six quality control samples with Fabp3 ranging from 0.256 to 25 ng, the average recovery following the procedure was about 73%, and the precision (%CV) between replicates was less than 7%. The Fabp3 concentrations in rat serum peaked 1 h after isoproterenol treatment, and returned to baseline levels 24 h after the dose. Elevated Fabp3 levels were also detected in rats administered with a PPAR α/δ agonist, which has shown to cause skeletal muscle necrosis. Fabp3 can be used as a biomarker for both cardiac and skeletal necroses. The cross‐validation of the LC‐SRM method with an existing ELISA method is described. 相似文献
62.
Josef Widder Martin Biely Günther Gridling Bettina Weiss Jean-Paul Blanquart 《Distributed Computing》2012,24(6):299-321
We consider the problem of reaching agreement in distributed systems in which some processes may deviate from their prescribed
behavior before they eventually crash. We call this failure model “mortal Byzantine”. After discussing some application examples
where this model is justified, we provide matching upper and lower bounds on the number of faulty processes, and on the required
number of rounds in synchronous systems. We then continue our study by varying different system parameters. On the one hand,
we consider the failure model under weaker timing assumptions, namely for partially synchronous systems and asynchronous systems
with unreliable failure detectors. On the other hand, we vary the failure model in that we limit the occurrences of faulty
steps that actually lead to a crash in synchronous systems. 相似文献
63.
Urban gravel‐bed stream channels in southern Ontario, Canada identified to be in a state of quasi‐equilibrium have been studied over the past 15 years and compared against rural gravel bed stream channels of the same hydrophysiographic region. Bankfull width and depth versus bankfull discharge were not found to increase as a function of increasing urbanization as has been found in many other studies. The observed annual frequency of bankfull discharge was typically less than a 1‐year return period with many sites ranging between 2 and 18 bankfull events per year with higher intensity and shorter duration urban flood responses, which further identified significant limitations in using annual peak discharge methods for predicting morphological forming flows in urban watersheds. The cumulative volume of bankfull and larger flood events from the urban stream channels were very similar to the same annual event volumes in the rural comparison study reaches. Bed material supply was found to decrease with increasing urbanization and the reduction in bed material supply appears to be off‐set by the smaller bankfull channel width, depth and access to floodplains during large flood events. Field evidence may also suggest a even greater reduction in channel width trajectory, relative to the rural setting, with expansive floodplains to maintain quasi‐equilibrium conditions as bed material supply continues to decrease with increased anthropogenic activity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
64.
Previous research by Bem has indicated that androgynous individuals of both sexes display "masculine" independence when under pressure to conform as well as "feminine" nurturance when interacting with a kitten. In contrast, sex-typed individuals were low in one or both of these behaviors. The two studies reported here were designed to replicate the low nurturance of the masculine male and to clarify the unexpected finding that feminine females were low in both independence and nurturance. In the first study subjects interacted with a human infant, and in the second study they listened to a lonely student. Taken together, the results of these two studies conceptually replicated the low nurturance of the masculine male and demonstrated that the low nurturance of the feminine female does not extend to her interaction with humans. Finally, evidence was presented in support of Spence, Helmreich, and Stapp's distinction between "androgynous" individuals, who are high in both masculinity and feminity, and "undifferentiated" individuals, who are low in both of these characteristics. 相似文献
65.
Paulson K.S. Watson R.J. Usman I.S. 《Antennas and Propagation, IEEE Transactions on》2006,54(1):168-174
This research examines route diversity as a fade mitigation technique in the presence of rain, for terrestrial microwave links. The improvement in availability due to diversity depends upon the complex spatio-temporal properties of rainfall. To produce a general model to predict the advantage due to route diversity it is necessary to be able to predict the correlation of rain attenuation on arbitrary pairs of microwave links. This is achieved by examination of a database of radar derived rain rate fields. Given a representative sample of rain field images, the joint rain attenuation statistics of arbitrary configurations of terrestrial links can be estimated. Existing rain field databases often yield very small numbers of high joint attenuation events. Consequently, estimates of the probability of joint high attenuation events derived from ratios of the number of occurrences can be highly inaccurate. This paper assumes that pairs of terrestrial microwave links have joint rain attenuation distributions that are bi-lognormally distributed. Four of the five distribution parameters can be estimated from ITU-R models. A maximum likelihood estimation (MLE) method is used to estimate the fifth parameter, i.e., the covariance or correlation. The predicted diversity statistics vary smoothly and yield plausible extrapolations into low probability situations. 相似文献
66.
Watson Jason M.; Bunting Michael F.; Poole Bradley J.; Conway Andrew R. A. 《Canadian Metallurgical Quarterly》2005,31(1):76
The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than individuals with reduced WMC when participants were forewarned about the tendency of associative lists (e.g., bed, rest, . . .) to elicit illusory memories for critical words (e.g., sleep). In contrast, both high and low WMC participants used repeated study-test trials to reduce recall of critical words. These findings suggest that individual differences in WMC influence cognitive control and the ability to actively maintain task goals in the face of interfering information or habit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Bill C. H. Chang Asanga Ratnaweera Saman K. Halgamuge Harry C. Watson 《Genetic Programming and Evolvable Machines》2004,5(2):203-214
In this paper, a modified particle swarm optimisation algorithm is proposed for protein sequence motif discovery. Protein sequences are represented as a chain of symbols and a protein sequence motif is a short sequence that exists in most of the protein sequence families. Protein sequence symbols are converted into numbers using a one to one amino acid translation table. The simulation uses EGF protein and C2H2 Zinc Finger protein families obtained from the PROSITE database. Simulation results show that the modified particle swarm optimisation algorithm is effective in obtaining global optimum sequence patterns, achieving 96.9 and 99.5 classification accuracy respectively in EGF and C2H2 Zinc Finger protein families. A better true positive hit result is achieved when compared to the motifs published in PROSITE database. 相似文献
68.
Kyoungo Nam Hyunki Park Kihak Im Dongjin Kim Heejae Ahn Jaehyuk Lee Jaewhan Moon Emma Watson Robert Shaw 《Fusion Engineering and Design》2013,88(6-8):701-704
The purpose-built, ITER tokamak assembly tools, which are to be provided by Korea, should be designed to meet: the assembly plan, space reservations, safety standards, simple operations, efficient maintenance, and so on. It is very important that the ITER assembly tools are able to lift and transfer ITER components or their sub-assemblies to their assembled position safely. Furthermore, the lifting tools will lift and handle very heavy loads that can be more than 1200 tonnes sometimes. Therefore, the ITER lifting tools must be designed to endure these heavy load conditions with regard to their structural integrity. Also, these designs should be verified through an appropriate method. The preliminary design of the sector lifting tool and associated lifting attachments are introduced in this paper. The sector lifting tool was designed especially to lift and handle various ITER components by adjusting the lifting centre. The structural analysis results using ANSYS are described considering the heaviest load condition. The results of the analysis show that; all stresses applied on the lifting tool are lower than the allowable stress of the applied material. 相似文献
69.
70.
M. A. Gordillo L. C. Zhang T. J. Watson M. Aindow 《Journal of Materials Science》2013,48(10):3841-3851
Devitrified Al—transition metal—rare earth alloys offer routes to obtain higher volume fractions of dispersed strengthening phases than conventional precipitation routes. Here, we report a study of the microstructure–property relationships of an Al–Ni–Co–Y alloy processed by gas atomization and consolidated/devitrified by warm extrusion. Microstructural characterization by electron microscopy and serial section FIB tomography show that the alloy comprises an FCC Al matrix and 44 % by volume of elongated Al19(Ni,Co)5Y3 plates with the Al19Ni5Gd3 structure. The plates are aligned with the extrusion direction in the as-extruded alloy, and tensile data show a distinct anisotropy in yield strength and strain to failure. These data are consistent with the alloy acting more like a unidirectional short-fiber-reinforced metal–matrix composite than a conventional precipitation-hardened alloy. During axial upset forging, the ternary plates do not break up, but instead they rotate, until at large upset strains they lie perpendicular to their original orientation with corresponding changes in the tensile properties. The materials exhibit yield strengths of up to 713 MPa and tensile elongations of up to 5 %. Thus, such systems could form the basis for truly deformable high-strength low-density metal–matrix composites. 相似文献