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141.
Artificial intelligence (AI) is a relatively young discipline, yet it has already led to general-purpose problem-solving methods and novel applications. Ultimately, AI's goals of creating models and mechanisms of intelligent action can be realized only in the broader context of computer science. Creating mechanisms for sharing of knowledge, knowhow, and literacy is the challenge. The great Chinese philosopher Kuan-Tzu once said: “If you give a fish to a man, you will feed him for a day. If you give him a fishing rod, you will feed him for life.” We can go one step further: If we can provide him with the knowledge and the know-how for making that fishing rod, we can feed the whole village. Therein lies the promise-and the challenge-of AI 相似文献
142.
P Sharma K Reddy N Franki V Sanwal R Sankaran TS Ahuja N Gibbons J Mattana PC Singhal 《Canadian Metallurgical Quarterly》1996,50(5):1604-1611
Hyperlipidemia has been demonstrated to contribute to hypercellularity of the mesangium in experimental animal models of glomerulosclerosis. We studied whether it also has the potential to convert a hypercellular mesangium into a hypocellular one by inducing mesangial cell (MC) apoptosis. Low density lipoprotein (LDL) enhanced (P < 0.001) mouse mesangial cell (MMC) proliferation at lower concentrations (control, 10.3 +/- 0.3 vs. LDL 100 micrograms/ml, 24.2 +/- 0.3 x 10(4) cells/ml) but augmented (P < 0.001) apoptosis at higher concentrations (control, 5.6 +/- 0.5% vs. LDL, 500 micrograms/ml 26.2 +/- 3.4% apoptotic cells/field). Oxidized (OX) LDL enhanced MMC apoptosis in concentrations of 50 to 200 micrograms/dl. There was a direct relationship between MMC apoptosis and oxidation of LDL as judged by measuring thiobarbituric acid reactive species (TBARS). Since superoxide dismutase (SOD) attenuated (P < 0.001) LDL-induced MMC apoptosis, it seems to be mediated through the generation of free radicals by mesangial cells (control, 4.3 +/- 1.5%; LDL, 200 micrograms/ml, 19.4 +/- 0.5%; LDL + SOD, 8.1 +/- 1.3% apoptotic cells/field). LDL also induced a similar effect on human mesangial cells. These studies were further confirmed by DNA fragment assays and ELISA for programmed cell death. LDL treated cells also showed enhanced mRNA expression for RSG-2, a marker for active cell death. These in vitro results provide a basis for the speculation that LDL has the potential to cause an initial hypercellular and subsequent hypocellular mesangium in the course of the development of glomerulosclerosis. 相似文献
143.
B. L. Narasimha Char B. R. Reddy S. D. Thirumala Rao 《Journal of the American Oil Chemists' Society》1977,54(11):494-495
Stones of mango fruit (Mangifera indica) were processed for recovery of fat and the fat refined. Mango kernel fat is potentially edible and can substitute for tallow and cacao butter. Mango kernal meal can be used as a sizing material and as a feed. 相似文献
144.
BS Reddy A Mastromarino C Gustafson M Lipkin EL Wynder 《Canadian Metallurgical Quarterly》1976,38(4):1694-1698
Fecal neutral steroids and bile acids were measured in patients with familial polyposis, family controls who are immediate relatives of patients, and controls other than relatives. All subjects were consuming a mixed Western diet at the time of collection of stool specimens. Although the total fecal neutral sterol concentrations were not different between the groups, the patients with familial polyposis excreted a high amount of cholesterol and low levels of coprostanol and coprostanone compared with other groups. Patients with familial polyposis excreted levels of total bile acids in their feces comparable to those excreted by controls; lithocholic acid excretion was decreased in patients with familial polyposis. These findings suggest that analysis of stools for cholesterol and its metabolites be useful in screening the siblings of polyposis families for latent disease. 相似文献
145.
N. L. Weinberg G. M. Blank H. A. Aulich A. Kentaro Hoffmann T. B. Reddy 《Journal of Applied Electrochemistry》1973,3(3):227-230
An electrochemical method has been developed for bonding electrically-conductive adherends. The procedure is based on the electrochemical generation of a curing agent from an otherwise chemically-unreactive precursor mixed with an epoxy resin sandwiched between the bonding members. The one-part epoxy resin is storage stable and cured rapidly on passage of current. 相似文献
146.
147.
Summary The integral of the form
, which arises in the convective heat transfer with constant wall temperature, is integrated by using Gauss-Laguerre and Gauss-Legendre Quadrature formulae. It is shown that the Nusselt number can be expressed explicitly in terms of the Prandtl number and the method proposed in this paper is valid for wide range of Prandtl numbers. Examples are given for the cases of flow over a semi-infinite plate and two-dimensional and axisymmetrical stagnations. The results are compared with the exact solutions for Prandtl numbers ranging from 0.006 to 100 (flat plate) and 0.01 to 50 (two-dimensional and axisymmetrical stagnation flows). 相似文献
148.
P. Mohan Babu G. Venkata Rao P. Sreedhara Reddy S. Uthanna 《Journal of Materials Science: Materials in Electronics》2004,15(6):389-394
Cadmium oxide films were grown on glass substrates using d.c. reactive magnetron sputtering technique by sputtering from a metallic cadmium target in an oxygen partial pressure of 1×10–3 mbar under various substrate bias voltages. The substrate bias voltage significantly influences the crystallographic structure of the deposited films. The influence of substrate bias voltage on the electrical and optical properties of the films was systematically studied. The films formed at a substrate temperature of 473 K and bias voltage of –80 V showed an electrical resistivity of 1×10–3 cm, optical transmittance of 86%, optical band gap of 2.47 eV and a figure of merit of 7×10–3 –1. 相似文献
149.
Ray MC Reddy JN 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(11):1477-1490
This paper deals with the active structural acoustic control of thin laminated composite plates using piezoelectric fiber-reinforced composite (PFRC) material for the constraining layer of active constrained layer damping (ACLD) treatment. A finite element model is developed for the laminated composite plates integrated with the patches of ACLD treatment to describe the coupled structural-acoustic behavior of the plates enclosing an acoustic cavity. The performance of the PFRC layers of the patches has been investigated for active control of sound radiated from thin symmetric and antisymmetric cross-ply and antisymmetric angle-ply laminated composite plates into the acoustic cavity. The significant effect of variation of piezoelectric fiber orientation in the PFRC layer on controlling the structure-borne sound radiated from thin laminated plates has been investigated to determine the fiber angle in the PFRC layer for which the structural-acoustic control authority of the patches becomes maximum. 相似文献
150.
We demonstrate sensitive spatially resolved detection of physiological chromophores that emit in the ultraviolet (<330 nm). An atypical laser source (a visible wavelength femtosecond optical parametric oscillator), and an unconventional collection geometry (a lensless detector that detects the forward-emitted fluorescence) enable this detection. We report the excitation spectra of the catecholamines dopamine and norepinephrine, together with near-UV emitters serotonin and tryptophan, in the range of 550-595 nm. We estimate the molecular two-photon action cross section of dopamine, norepinephrine, and serotonin to be 1.2 mGM (1 GM, or Goppert Mayor, is equal to 10(-58) m4 s(-1) photon(-1)), 2 mGM, and 43 mGM, respectively, at 560 nm. The sensitivity achieved by this method holds promise for the microscopic imaging of vesicular catecholamines in live cells. 相似文献