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51.
Robotica is a computer aided design package for robotic manipulators developed in the Coordinated Science Laboratory at the University of Illinois at Urbana-Champaign. It encapsulates over 30 functions into a Mathematica package allowing efficient symbolic and numeric calculation of kinematic and dynamic equations for multi-degree-of-freedom manipulators. An X-Windows front end that utilizes the interprocess communication features of Mathematica 2.1 has also been created for ease of use. This paper describes the most important features of the package and how they are used 相似文献
52.
Twenty-six patients with an intracardiac myxoma underwent surgical resection at our institution from 1977 through 1992. Left atrial myxoma was diagnosed in 22 patients, left ventricular in 1, right atrial in 2, and right ventricular in 1. Six patients were asymptomatic; preoperative symptoms included dyspnea, arrhythmias, embolic episodes, and syncope. The diagnosis was established with transthoracic echocardiography in all cases but one. Surgery was performed in all cases with the aid of cardiopulmonary bypass with moderate hypothermia and cold crystalloid cardioplegia. One patient with a left ventricular myxoma died in a comatose state during the immediate postoperative period. Long-term clinical and echocardiographic evaluation was performed in 19 patients; results were excellent (all the patients were in New York Heart Association functional class I or II), and no recurrences were documented. The clinical characteristics, diagnostic methods, and surgical approach are presented and discussed. 相似文献
53.
实验研究了以工业硫酸亚铁及废硫酸为原料,分别采用NaClo_3、KClO_3、H_2O_2及(o_2+NaNO_2)为氧化剂成聚硫酸铁的条件。在以(O_2+NaNO_2)为氧化剂的合成过程中,发现添加微量助催化剂(型号为HG-1、HG-2和HG-3),对提高合成速度及反应过程的稳定性具有重大作用。 相似文献
54.
Surveyed 70 practicing attorneys and 150 law students to determine the extent to which they felt it was their responsibility to inform clients they referred for psychological testing about the testing process and about the validity scales on tests. Results showed that almost 50% of the attorneys and over 33% of the students believe that clients referred for testing always or usually should be informed of validity scales on tests. These results suggest that many test takers, particularly in forensic settings, may have information about validity scales that facilitates their giving biased responses without detection. Psychologists doing forensic evaluations should be alert to this possibility and should consider using more than one approach to detect response distortions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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57.
Schottky diodes of aluminium/poly(3-octylthiophene)(P30T)/indium-tin oxide with large active area are prepared by using the proposed new casting technique. Their rectifying behavior and junction characteristics are dependent on whether the P30T is doped and on the storage time, but independent of the thickness of the P30T layer. The present technique can also be applied in a fabrication of electronic devices with other soluble conjugated polymers. 相似文献
58.
The effect of a novel flavonoid, venoruton (a mixture of mono-, di-, tri- and tetrahydroxyethylrutosides) has been investigated in healthy rat lenses and compared with diabetic cataract modelled in vitro. One mM venoruton was added to medium simulating healthy and diabetic conditions for the incubated lenses; damage was followed by either stereoscopic photography of the lenses under a Cooperative Cataract Research Group operating microscope or with our recently developed method: the leakage of lactate dehydrogenase (LDH) into the lens culture media. The increased LDH activity in the medium and observable development of the opacity were correlated with cell damage, which has been found to be associated with globular degeneration and cataract formation. The extent of opacification and LDH release is reduced if 1 mM venoruton is included in the medium. The protective effect may be related to antioxidant activity against reactive oxygen species: decreased luminol luminescence was shown after venoruton addition to either superoxide-generating hypoxanthine plus xanthine oxidase, or hydrogen peroxide. 相似文献
59.
A novel class of narrow-band tunable wavelength filters is proposed and evaluated. Wavelength selectivity of the proposed filters Is derived from the finite time response of an optical nonlinearity. The nonlinearity is gain saturation in semiconductor optical amplifier structures. The filters are shown to have very narrow passbands tunable over the entire semiconductor gain bandwidth. The key to filter implementation is a device configuration in which the wave-mixing products can be isolated from the amplified inputs. Three integrated optics compatible configurations are considered and shown to have high filter throughputs 34 to 180% and subangstrom bandwidths 相似文献
60.
It is not known whether impaired hematopoiesis noted during human immunodeficiency virus (HIV) infection results from infection of stem/progenitor cells or of cells of the bone marrow microenvironment. Normal adherent primary stromal layers were exposed to HIV to determine which of this mixture of endothelial cells, fibroblasts, and macrophages are susceptible to the virus. Viral p24 in supernatants was noted with monocytotropic HIV-1Ada, HIV-1Ba-L, and HIV-1JR-FL but not with lymphotropic HIV-1LAI nor HIV-1MN strain, and only stromal macrophages expressed the viral antigens. Coculture of the layers with PHA-activated normal lymphocytes failed to rescue lymphotropic virus. No p24 was produced when macrophage-depleted stromal cells were exposed to either HIV-1Ba-L or HIV-1LAI; proviral DNA was then amplified by PCR in cells exposed to either virus, though coculture with lymphocytes rescued only HIV-1Ba-L. Altogether, these data indicate that macrophages are the major targets of HIV in cultured stromal layers. As virus replication in macrophages did not affect the profile of major cytokines involved in regulating hematopoiesis, HIV infection could alter hematopoiesis by other as yet unspecified mechanisms. 相似文献