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51.
ABSTRACT

In this paper, (strongly) b-V-KT-pseudoinvex multidimensional control problems are considered. Concretely, we introduce a generalised condition on the functionals involved in a multidimensional vector control problem and prove that a (strongly) b-V-KT-pseudoinvex multidimensional control problem is characterized so that all Kuhn–Tucker points are efficient solutions. In addition, the theoretical results derived in this paper are illustrated with an application.  相似文献   
52.
In chronic renal insufficiency resulting from destruction of the vast majority of nephrons, the surviving nephrons adapt their functions to the conditions of vigorous haemodynamic and osmolar overloads. They acquire an appropriate behaviour to preserve the principal renal functions and to achieve the balance of inner space. In the long period of time, similarly as in healthy people. Glomerulotubular balance as well as tubuloglomerular balance distinguish the remaining nephron function, while autoregulation of perfusion pressure along the glomerulus rapidly vanishes. All three regulation mechanisms are characteristic of the nephron function under physiologic conditions. Intense work of the remaining nephrons in chronic renal failure is under the high level controls of the group of hormones, among them are rennin-angiotensin system, arginine-vasopressin and atrial natriuretic peptide playing very important and particular roles. Comparison of different published studies emerge the idea that chronically increased arginine-vasopressin levels in chronic renal failure could block the autoregulation of blood flow and hydraulic pressure in glomeruli, which together with other mediator actions give high and fluctuating tense within remaining glomeruli, during every single cardiac cycle. It is probably the main event in the further course of kidney disease progression resulting in definite damage of the overloaded nephrons. Angiotensin II is one of reliably recognised mediators of unfavourable outcome in the process of nephron adaptation in chronic renal failure. Knowing the pathophysiologic processes in the remaining functionally adapted nephrons in chronic renal insufficiency determines a more adequate therapeutic approach in these patients.  相似文献   
53.
Results are presented from a study of the effect of saturation pressure on the nonsteady critical heat flux during the boiling of liquid helium in a large volume.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 48, No. 1, pp. 16–18, January, 1985.  相似文献   
54.
55.
The results of an experimental investigation of electrodynamic characteristics of a meander microstrip line with a ferromagnetic film are presented for different values of an external magnetic field. It is found that, in the presence of a ferrite film, higher-order modes caused by perturbation of corresponding modes of a multilayered meander line are excited in the passband of a higher-order mode of the meander line. These modes propagate in dielectric substrates of the meander line and the ferromagnetic film. The effect of transmission of the active power in the stopband of the meander line with a ferromagnetic film is discovered. This effect also arises in the case of excitation of magnetostatic waves.  相似文献   
56.
The properties of amorphous metallic molybdenum–silicon–nitrogen (Mo–Si–N) films were characterised for use in nanoelectronic applications. The films were deposited by co-sputtering of molybdenum and silicon targets in a gas mixture of argon and nitrogen. The atomic composition, microstructure and surface roughness were studied by RBS, TEM and AFM analyses, respectively. The electrical properties were investigated in the temperature range 80 mK to 300 K. No transition into a superconductive state was observed. Nanoscale wires were fabricated using electron beam lithography with their properties measured as a function of temperature.  相似文献   
57.
A new class of 16-membered macrolides, the epothilones (Epos), has been synthesized and evaluated for antitumor potential in vitro and in vivo. Recent studies in these and other laboratories showed that epothilones and paclitaxel (paclitaxel) share similar mechanisms of action in stabilizing microtubule arrays as indicated by binding-displacement studies, substitution for paclitaxel in paclitaxel-dependent cell growth, and electron microscopic examinations. The present study examined cell growth-inhibitory effects in two rodent and three human tumor cell lines and their drug-resistant sublines. Although paclitaxel showed as much as 1, 970-fold cross-resistance to the sublines resistant to paclitaxel, adriamycin, vinblastine, or actinomycin D, most epothilones exhibit little or no cross-resistance. In multidrug-resistant CCRF-CEM/VBL100 cells, IC50 values for EpoA (1), EpoB (2), desoxyEpoA (3) (dEpoA), desoxyEpoB (4) (dEpoB), and paclitaxel were 0.02, 0.002, 0.012, 0.017, and 4.14 microM, respectively. In vivo studies, using i.p. administration, indicated that the parent, EpoB, was highly toxic to mice and showed little therapeutic effect when compared with a lead compound, dEpoB. More significantly, dEpoB (25-40 mg/kg, Q2Dx5, i.p.) showed far superior therapeutic effects and lower toxicity than paclitaxel, doxorubicin, camptothecin, or vinblastine (at maximal tolerated doses) in parallel experiments. For mammary adenocarcinoma xenografts resistant to adriamycin, MCF-7/Adr, superior therapeutic effects were obtained with dEpoB compared with paclitaxel when i.p. regimens were used. For ovarian adenocarcinoma xenografts, SK-OV-3, dEpoB (i.p.), and paclitaxel (i. v.) gave similar therapeutic effects. In nude mice bearing a human mammary carcinoma xenograft (MX-1), marked tumor regression and cures were obtained with dEpoB.  相似文献   
58.
1.  Damage initiation under conditions of low-cycle loading at the working temperature of discs and shafts that are made from the ÉP741NP PM alloy takes place on local structure defects.
2.  The dominant form of damage initiation sites in LCF of the studied alloy are nonmetallic inclusions of size no larger than the maximal granule dimension (200 m).
All-Union Institute of Light Alloys. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 6, pp. 32–34, June, 1993.  相似文献   
59.
2D Eddy current sensor array   总被引:1,自引:4,他引:1  
This paper presents the design and development of a two-dimensional eddy current sensor array and the improved response of the array using a super-resolution algorithm. A computational model of the array is derived using dyadic Green's function and volume integral method. This application was realized for detecting fatigue cracks, introduced in AISI 304 samples by subjecting them to cyclical loading.  相似文献   
60.

This article presents the results of the series of experimental tests of a packaged RF MEMS switch manufactured as a chip on a silicon substrate in the Center for Materials and Microsystems of Fondazione Bruno Kessler. Experiments have been performed up to 25 GHz and included S-parameters check in different operation and environmental conditions, including variation of input power, ambient temperature and number of switching cycles. Presented RF MEMS SPST switch is a basic element of more complex reconfigurable networks such as SPxT switches, phase shifters, power attenuators etc.

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