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1.
Paul Mulholland Zdenek Zdrahal John John Domingue Marek Hatala 《Behaviour & Information Technology》2000,19(3):171-180
Integrating working and learning is seen as a desirable alternative to traditional training regimes. An integrated approach to working and learning is more gradual, contextual, problem oriented and cost effective. Knowledge technology aims to catalyze workplace learning, but requires the right organisational culture and brings additional costs regarding the articulation, representation and transmission of knowledge. Our approach reduces these costs by making articulation a natural part of collaborative working, designing for both informal and formal knowledge, and facilitating the transition of socially situated knowledge through enriched documents. To be successful, our approach has certain prequesites concerning organisational culture, and the nature of shared documents, organisational knowledge and work activities. 相似文献
2.
Preoperative radiotherapy for adenocarcinoma of the rectosigmoid 总被引:2,自引:0,他引:2
Ninety-seven patients with adenocarcinoma of the rectosigmoid have been treated with high dose (5000-6000 rad) preoperative irradiation from 1960 through 1972 at the University of Oregon Health Sciences Center. Fifty-seven were initially clinically resectable and 40 were initially inoperable. Forty of the 57 initially clinically resectable patients had "curative" resections and are at risk for more than 5 years. An increase in 5-year survival (from 38% to 53%) and an absence of pelvic recurrence have occurred in those patients receiving preoperative irradiation and "curative" resection. Four of the 40 initially inoperable patients are alive without tumor. Three of the four survivors had irradiation and surgery; one had irradiation only. An additional four patients had no evidence of tumor at death. Tumor was totally sterilized by irradiation and nine patients and reduced to microfocal extent in an additional three of the 97 patients. Incidence of complications was no greater than has been reported in a surgical series from the same institution. 相似文献
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KR Cooke 《Canadian Metallurgical Quarterly》1976,437(1):280-288
(1) Partial replacement of medium chloride by bicarbonate, with pHmaintained constant by addition of CO2, lead to a greater rate of swelling when rat renal corti cal slices were leached in nitrogenated medium at 0--2 degree C. This greater rate of swelling was still present when 1 mM iodoacetate was added to the leaching media. (2) Rat renal cortical slices incubated in oxygenated bicarbonate medium at 25 degree C maintained a slightly greater tissue water content than did slices incubated in phosphate-buffered media. Inclusion of malate in the incubation medium also led to a greater steady-state water content when slices were incubated at 25 degree C in oxygenated media. These results suggest that that particular cell volume which is maintained by metabolism and the double Donnan system is determined at least in part by the nature of the extracellular anions. (3) The rates of net sodium extrusion and of net potassium uptake were not significantly altered by presence of CI2 and bicarbonate in the incubation medium. 相似文献
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A progressive fibrous myopathy may result from chronic intramuscular drug abuse. This complication may mimic other rheumatic disorders and early recognition may prevent disability. The patient described here presented with fixed flexion and extension contracture of hips and knees, respectively, after abusing meperidine and other agents for 3 years. Soft tissues of thighs and buttocks were "wood hard," EMG showed absence of action potentials in affected muscles, and biopsy revealed extensive replacement of muscle with dense, acellular fibrous tissue. Possible mechanisms are discussed. 相似文献
7.
Anthocyanins were identified and quantified in various cultivars of blueberries grown in Australia. Those were Crunchie, Star and Sharpe (highbush, Vaccinium corymbosum L.) and Climax, Powderblue and Brightwell (rabbiteye, Vaccinium ashei). A method was developed involving liquid chromatography–mass spectrometry and UV–visible spectroscopy. The repeatability of injection was less than 2% relative standard deviation (RSD) while the repeatability of sample preparation was less than 10% RSD in most cases. The method was linear between 7% and 100% of the original concentration. The anthocyanin profile was similar in all cultivars but proportions of each compound were cultivar-dependent. Highbush had more early eluting peaks, i.e. more polar anthocyanins, than rabbiteye cultivars. Delphinidin, petunidin and malvidin were the major contributors to total anthocyanin content. Climax had the highest total anthocyanin content (13.7 ± 1.4 g cyanidin 3-glucoside equivalent kg−1 dry weight) and antioxidant activity (using 2,2-diphenyl-1-picrylhydrazyl as a free radical) of all tested cultivars. Rabbiteye had significantly higher total anthocyanin content than the highbush cultivars. 相似文献
8.
Dynamic Matrix Control (DMC) has proven to be a powerful tool for optimal regulation of chemical processes under constrained conditions. It is based on a linear convolution model derived from step-response measurements. A model predictive control algorithm optimises closed-loop performance for a nominal operating point. However, as the process moves away from this point, control usually becomes sub-optimal due to process non-linearity. As seen in this work, the DMC algorithm can be made adaptive, to establish a new local model, by recursive estimation of the local step response parameters from normal plant variations. However, when used for control of plants containing integrating process units, steady-state offsets occur for sustained changes. Thus, a novel Adaptive Linear Dynamic Matrix Control (ALDMC) algorithm has been developed and used to control a 2-input/2-output system with an integrating behaviour. Comparisons of model control and plant control with and without these features demonstrated the importance of integral compensation for integrating processes, and model adaptation in the case of plant/model mismatch. Some cross-compensation of integration by the adaptive feature was also noted. An holistic technique is demonstrated which simultaneously recognises residual integration disturbances and matrix parameter variations, whereas previous techniques which recognise only one of these will fail in the presence of the other. 相似文献
9.
A method to determine arbitrary moments of aerosol size distributions from differential mobility analyzer measurements has been proposed. The proposed method is based on a modification of the algorithm developed by Knutson and Whitby to calculate the moments of electrical mobility distributions. For this modification, the electrical mobility and the charge distribution have been approximately expressed by power functions of the particle diameter. To evaluate the validity of the approximation, we have carried out numerical simulations for typical size distributions. We have found that for typical narrowly distributed aerosols such as polystyrene latex particles and particles that arise in the tandem differential mobility analyzer configuration, the distribution parameters can be accurately determined by this method. For a log-normally distributed aerosol, the accuracy of the distribution parameters determined by this method has been evaluated as a function of the geometric standard deviation. We have also compared the accuracy of the proposed method with other existing methods in the case of the asymmetric Gaussian distribution. 相似文献
10.
Preservation of protein fluorescence in embedded human dendritic cells for targeted 3D light and electron microscopy 下载免费PDF全文
K. HÖHN J. FUCHS A. FRÖBER R. KIRMSE B. GLASS M. ANDERS‐ÖSSWEIN P. WALTHER H.‐G. KRÄUSSLICH C. DIETRICH 《Journal of microscopy》2015,259(2):121-128
In this study, we present a correlative microscopy workflow to combine detailed 3D fluorescence light microscopy data with ultrastructural information gained by 3D focused ion beam assisted scanning electron microscopy. The workflow is based on an optimized high pressure freezing/freeze substitution protocol that preserves good ultrastructural detail along with retaining the fluorescence signal in the resin embedded specimens. Consequently, cellular structures of interest can readily be identified and imaged by state of the art 3D confocal fluorescence microscopy and are precisely referenced with respect to an imprinted coordinate system on the surface of the resin block. This allows precise guidance of the focused ion beam assisted scanning electron microscopy and limits the volume to be imaged to the structure of interest. This, in turn, minimizes the total acquisition time necessary to conduct the time consuming ultrastructural scanning electron microscope imaging while eliminating the risk to miss parts of the target structure. We illustrate the value of this workflow for targeting virus compartments, which are formed in HIV‐pulsed mature human dendritic cells. 相似文献