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71.
VN Bhattathiri L Bindu P Remani B Chandralekha CA Davis MK Nair 《Canadian Metallurgical Quarterly》1996,41(2):139-142
The role of the propeptide sequence and a disulfide bridge between sites 1 and 122 in chymotrypsin has been examined by comparing enzyme activities of wild-type and mutant enzymes. The kinetic constants of mutants devoid of the Cys1-Cys122 disulfide-linked propeptide show that this linkage is not important either for activity or substrate specificity. However this linkage appears to be the major factor in keeping the zymogen stable against non-specific activation. A comparison of zymogen stabilities showed that the trypsinogen propeptide is ten times more effective than the chymotrypsinogen propeptide in preventing non-specific zymogen activation during heterologous expression and secretion from yeast. This feature can also be transferred in trans to chymotrypsinogen; i.e. the chymotrypsin trypsin propeptide chimera forms a stable zymogen. 相似文献
72.
73.
Michael Anthony Puso Tod A. Laursen 《International journal for numerical methods in engineering》2002,54(8):1161-1194
In this work, a method is developed for smoothing three‐dimensional contact surfaces. The method can be applied to both regular and irregular meshes. The algorithm employs Gregory patches to interpolate finite element nodes and provide tangent plane continuity between adjacent patches. The resulting surface interpolation is used to calculate gaps and contact forces, in a variationally consistent way, such that contact forces due to normal and frictional contact vary smoothly as slave nodes transition from one patch to the next. This eliminates the ‘chatter’ which typically occurs in a standard contact algorithm when a slave node is situated near a master facet edge. The elimination of this chatter provides a significant improvement in convergence behaviour, which is illustrated by a number of numerical examples. Furthermore, smoothed surfaces also provide a more accurate representation of the actual surface, such that resulting stresses and forces can be more accurately computed with coarse meshes in many problems. This fact is also demonstrated by the numerical examples. Published in 2002 by John Wiley & Sons, Ltd. 相似文献
74.
Dimitrios Tzovaras Nikos Grammalidis Michael G. Strintzis 《Signal Processing: Image Communication》1998,11(3):205-230
In the present paper techniques are examined for the coding of the depth map and disparity fields for stereo or multiview image communication applications. It is assumed that both the left and right channels of the multiview image sequence are coded using block- or object-based methods. A dynamic programming algorithm is used to estimate a disparity field between each stereo image pair. Depth is then estimated and occlusions are optionally detected, based on the estimated disparity fields. Spatial interpolation techniques are examined based on the disparity/depth information and the detection of occluded regions using either stereoscopic or trinocular camera configurations. It is seen that the presence of a third camera at the transmitter site improves the estimation of disparities, the detection of occlusions and the accuracy of the resulting spatial interpolation at the receiver. Various disparity field and depth map coding techniques are then proposed and evaluated, with emphasis given to the quality of the resulting intermediate images at the receiver site. Block-based and wireframe modeling techniques are examined for the coding of isolated depth or disparity map information. Further, 2D and 3D motion compensation techniques are evaluated for the coding of sequences of depth or disparity maps. The motion fields needed may be available as a byproduct of block-based or object-based coding of the intensity images. Experimental results are given for the evaluation of the performance of the proposed coding and spatial interpolation methods. 相似文献
75.
D Davis 《Canadian Metallurgical Quarterly》1993,24(4):50-51
Recommendations resulting from a JCAHO survey can be a true blessing as they force nursing departments to assess critically their professional practice and documentation systems. Systematic preparation, begun at least two years prior to the survey, includes Nursing Administration, a Nursing Documentation Task Force and all staff nurses. Educational consultants assigned to each unit bring nurses up-to-date on nursing process and nursing diagnosis. Mock surveys and cross-training in chart review prepare staff nurses for confident participation in the accreditation process. 相似文献
76.
We have developed an electronic classroom environment based on an analog/digital hybrid network, ComWeb. This environment supplements traditional methods of presentation by providing powerful communication tools between the students and the teacher directed from the instructor's workstation. The instructor can access every student's workstation at any time to monitor the student's work or to transmit information from any source. ComWeb has facilities for individual and group supervision. It can be adapted for teaching deaf or hard of hearing students in a mainstream environment. We describe the implementation of a ComWeb-based classroom at our site. The performance of students in conventional sections of a computer literacy course is compared with that in a section using ComWeb. For most of the material, performance of students in the ComWeb based section was markedly superior. 相似文献
77.
Development of a new scale to measure patient behavior in group psychotherapy, the Individual Group Member Interpersonal Process Scale (IGIPS), is described. This scale captures clinically important aspects of how patients act in group, including how they respond to the other group members. The IGIPS was applied to videotapes of the first four sessions of seven 15-session outpatient therapy groups (52 patients) in the Mental Health Department of a health maintenance organization. The scale was found to have five factors (Activity, Interpersonal Sensitivity, Comfort with Self, Self-Focus, and Psychological Mindedness). Patient behavior that was moderate on two IGIPS dimensions was connected with better outcome than was that of patients with more extreme behavior in either direction. 相似文献
78.
79.
Michael E. G. Ferguson Peter L. Spedding 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):262-278
Experimental data for air–water two-phase co-current flow in two different pipe diameters were used to test the prediction of pressure drop by a number of existing theories and correlations. Several models are shown to be useful for prediction, particularly with the stratified regimes which have proved difficult to handle in the past. The model suggested by Olujic proved to be of particular value. 相似文献
80.
In many firms' experience, reusing elements of proven systems designs and software is best done through a companywide program. Reuse means savings in design, testing, manufacturing and support. The author gives the basic information a company needs to get started. The author discusses the context for reuse, planning and strategy involved in a reuse program 相似文献