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81.
Towards an Environmentally Acceptable Heterogeneous Catalytic Method of Producing Adipic Acid by the Oxidation of Hydrocarbons in Air 总被引:1,自引:0,他引:1
Raja Robert Lee Sang-Ok Sanchez-Sanchez Manuel Sankar Gopinathan Harris Kenneth D.M. Johnson Brian F.G. Thomas John Meurig 《Topics in Catalysis》2002,20(1-4):85-88
A survey is given of the catalytic methods potentially available for the production of adipic acid by the oxidation of readily available hydrocarbon precursors under environmentally benign conditions. Encouraging results are reported using H2O2 as oxidant and microporous FeAlPO-5 as catalyst at moderate temperatures. 相似文献
82.
Primary focal segmental glomerulosclerosis (FSGS) is a lesion associated with a poor prognosis and results in end-stage renal disease after 5 to 10 years. Based on past experience, many nephrologists have considered primary FSGS a lesion that is steroid resistant and therefore are reluctant to offer steroids as treatment. Recent data, however, have demonstrated that patients with primary FSGS have a response to steroid therapy that is considerably better than had been described. Thus, it may be that nephrologists have been more "steroid reluctant" than the lesion is steroid resistant. To better understand this issue we review the clinical course and response to therapy in patients with primary FSGS. 相似文献
83.
Cell-matrix interactions have major effects upon phenotypic features such as gene regulation, cytoskeletal structure, differentiation, and aspects of cell growth control. Programmed cell death (apoptosis) is crucial for maintaining appropriate cell number and tissue organization. It was therefore of interest to determine whether cell-matrix interactions affect apoptosis. The present report demonstrates that apoptosis was induced by disruption of the interactions between normal epithelial cells and extracellular matrix. We have termed this phenomenon "anoikis." Overexpression of bcl-2 protected cells against anoikis. Cellular sensitivity to anoikis was apparently regulated: (a) anoikis did not occur in normal fibroblasts; (b) it was abrogated in epithelial cells by transformation with v-Ha-ras, v-src, or treatment with phorbol ester; (c) sensitivity to anoikis was conferred upon HT1080 cells or v-Ha-ras-transformed MDCK cells by reverse-transformation with adenovirus E1a; (d) anoikis in MDCK cells was alleviated by the motility factor, scatter factor. The results suggest that the circumvention of anoikis accompanies the acquisition of anchorage independence or cell motility. 相似文献
84.
STUDY DESIGN AND METHODS: This study used an anatomically detailed model of the lumbar tissues, driven from biologic signals of vertebral displacement and myoelectric signals, to estimate individual muscle and passive tissue force-time histories during the performance of the "flexion-relaxation" maneuver. Eight male university students performed three trials each of the "flexion-relaxation" maneuver with six pairs of surface myoelectric electrodes monitoring the right side of the trunk musculature, an electromagnetic device to record lumbar flexion, and videotape to record body segment displacement. OBJECTIVES: To examine the loads on individual tissues during the transfer of moment support responsibility from predominantly active muscle to predominantly passive tissue. SUMMARY OF BACKGROUND DATA: No previous studies, to the authors' knowledge, have examined individual tissue loading during the flexion-relaxation maneuver. RESULTS: Although most subjects were able to "relax" their lumbar extensors in full flexion, activity remained in the thoracic extensors and abdominals. Tissue load predictions suggested that while the lumbar extensor muscles were neurally "relaxed" (i.e., myoelectric silence), substantial elastic forces would assist the passive tissues in extensor moment support. On average, subjects sustained almost 3 kN in compressive load on the lumbar spine and about 755 N of anterior shear during full flexion with only 8 kg held in the hands. CONCLUSIONS: The "relaxation" of lumbar extensor muscles appeared to occur only in an electrical sense because they generated substantial force elastically through stretching. Loading of the interspinous and supraspinous ligaments, in particular, was high relative to their failure tolerance. 相似文献
85.
The objective of the study was to evaluate the role of autologous blood transfusion in current clinical practice in the Federal Republic of Germany after reunification. METHODS: Questionnaires were sent to the anaesthesia departments of 684 German hospitals in January 1993. The sample consisted of 400 randomly selected hospitals from the former West Germany ("old federal states") and 284 hospitals from the former German Democratic Republic ("new federal states"). Only hospitals with more than 25 surgical beds were included in the study. The questionnaire contained 36 questions related to (1) general information on the hospital, (2) preoperative autologous blood donation (PABD), (3) preoperative plasmapheresis, (4) isovolaemic haemodilution, (5) perioperative blood salvage, and (6) general management of blood transfusion. RESULTS: A total of 502 completed questionnaires (73%) were returned, 305 from hospitals in the "old federal states" and 197 from hospitals in the former German Democratic Republic. Nine per cent of the responding hospitals were running their own transfusion services, and 56% were located in the vicinity of a regional blood bank. The overall proportion of surgical procedures requiring perioperative blood transfusion ranged from 1% to 90% (median 10%). PABD was performed "not at all" in 18%, "rarely" in 20% "occasionally" in 27%, "frequently" in 17%, and "mostly" in 16% of the responding hospitals. The principal use of PABD was in orthopaedic surgery and cardiac surgery (83% and 70% of the departments in question, respectively). In more than 50% of the hospitals reporting, the PABD service was run by the anaesthesia department. Patients not meeting the established criteria for homologous blood donors were accepted for autologous blood donation "frequently" and "mostly" in 20% and 12% of the hospitals, respectively, but at most "occasionally" in 63% of the hospitals. Preoperative plasmapheresis was performed in 12% of the responding hospitals. Autologous fresh frozen plasma predominantly was used for volume replacement, and for prevention of coagulation disorders when major blood loss was anticipated. Isovolaemic haemodilution was performed "not at all" in 28%, "rarely" in 19%, "occasionally" in 28%, "frequently" in 16%, and "mostly" in 8% of the responding hospitals. The reasons most frequently invoked for not performing haemodilution were "too time consuming" and "too little blood-saving effect". Cell separators for perioperative blood salvage were available in 30% of the responding hospitals. Of the other hospitals not equipped with cell-washing devices, 11% performed perioperative blood salvage of unprocessed blood by means of simple collection devices. Some 80% of those hospitals using intraoperative autotransfusion devices also performed blood salvage postoperatively. The principal use of perioperative blood salvage was in cardiac surgery, orthopaedics, and vascular surgery (90%, 54%, and 54% of departments, respectively). Some 48% of the responding anaesthetists "mostly" considered haemoglobin levels of 8-10 g/dl acceptable in patients without cardiopulmonary disease, but only 18% did so in patients with cardiopulmonary disease. CONCLUSIONS: Although available in the majority of hospitals surveyed, the simple techniques of both PABD and isovolaemic haemodilution are unduly neglected in routine clinical practice. The consistent use of both of these techniques, and the careful weighing up of the indication for every single blood transfusion, would not only effectively reduce homologous blood transfusions, but also enable even small hospitals to run successful autologous transfusion programmes without expensive cell-washing and plasmapheresis devices. 相似文献
86.
Using the consumer-oriented approach of social and commercial marketers, this article presents a process for crafting messages designed to improve people's health behaviors. The process, termed consumer-based health communications (CHC), transforms scientific recommendations into message strategies that are relevant to the consumer. The core of CHC is consumer research conducted to understand the consumer's reality, and thereby allowing six strategic questions to be answered. The immediate result of the CHC process is a strategy statement--a few pages that lay out who the target consumer is, what action should be taken, what to promise and how to make the promise credible, how and when to reach him or her, and what image to convey. The strategy statement then guides the execution of all communication efforts, be they public relations, mass media, direct marketing, media advocacy, or interpersonal influence. It identifies the most important "levers" for contact with the consumer. Everyone from creative specialists through management and program personnel can use the strategy statement as a touchstone to guide and judge the effectiveness of their efforts. The article provides a step by step illustration of the CHC process using the 5 A Day campaign as an example. 相似文献
87.
88.
Wireless Personal Communications - One of the applications of Sparse Linear Wireless Sensor Networks is environmental monitoring. In these networks, sensors are deployed in sensitive and strategic... 相似文献
89.
Raja Muhammad Asif Zahoor Naz Hira Shoaib Muhammad Mehmood Ammara 《Neural computing & applications》2022,34(7):5771-5790
Neural Computing and Applications - In the present study, a novel application of backpropagated neurocomputing heuristics (BNCH) is presented for epidemic virus model that portrays the Stuxnet... 相似文献
90.
M. Adam Khan N. Ram Prasad S. Navaneetha Krishnan S. Karthic Raja J. T. Winowlin Jappes Muthukannan Duraiselvam 《Materials and Manufacturing Processes》2017,32(14):1635-1641
The recent research in biocompatible materials has been useful in replacing and supporting the fractured natural human bones/joints. Under some condition, negative reaction like release of ions from the bare metal toward the human body fluid leads to corrosion. In this proposed research paper, the biocompatibility of the laser surface-modified austenitic stainless steel (SS316L) and nickel-based superalloy (Inconel 718) was studied. The investigation on laser-modified surfaces is evaluated through electrochemical polarization analysis using simulated body fluid (SBF). The samples subjected to electrochemical polarization analysis were characterized by optical image analysis, SEM, EDS, and XRD analysis. It was inferred that laser surface-modified materials provided enhanced corrosion resistance and bare nickel alloy is more susceptible to corrosion by SBF. 相似文献