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51.
Conclusions Alloy AT2 and weldments of the alloy have high strength and ductility at temperatures from 500 to –253°. The deformability of the weld seam is approximately the same as that of the alloy. The corrosion resistance in hydrochloric and phosphoric acids is the same for the weld seam and the base metal. Alloy AT2 and weldments of the alloy are more resistant to hydrochloric and phosphoric acids than alloy VT1.E. O. Paton Institute of Electric Welding of the Academy of Sciences, Ukrainian SSR. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 66–68, January, 1976.  相似文献   
52.
A model of instrumental conditioning similar to the classical model (Pavlovian) is proposed. Flexion of the ipsilateral forelimb was elicited while EDS was applied to the hind limb by stimulation of the motor area of the cortex (M1); both stimuli ceased during the raising of the forelimb. Uniform combinations of this kind led to the development of forepaw flexion reactions in response to the EDS of the hind paw. Prolongation of EDS by 3 sec following cortical stimulation led to rapid extinction of the developed reactions. Thus, the possibility of the effective instrumentalization of movements induced by stimulation of the M1 is proven. This argues that the forming "instrumental" connection (drive-motor structures) is addressed directly to the M1.  相似文献   
53.
We have experimentally studied the action of high-power plasma flows on pure tungsten plates covered with multilayer films of tungsten nanoparticles formed by the method of laser electrodeposition. The samples were irradiated using a plasma gun producing hydrogen (helium) plasma flows with power density up to 35 GW/cm2. The resulting surface morphology was studied by scanning electron microscopy (SEM). SEM data showed that tungsten plates coated by nanoparticles are more resistant to the formation of microcracks than are pure tungsten plates.  相似文献   
54.
PURPOSE: The goal of this research was to discover new biological indicators in urine which could be used for short-term prognosis of local Bacillus Calmette-Guerin (BCG) therapy outcome in patients with superficial bladder cancer. PATIENTS AND METHODS: We measured and statistically evaluated soluble immunological molecules in urine from bladder cancer patients (n = 34) receiving BCG intravesically. Urine was collected following each of 6 weekly treatments, processed and assayed. The data base included measurements of interleukin-1 (IL-2, IL-4, IL-6, IL-10, IL-12, soluble intercellular adhesion molecule-1 (sICAM-1), tumour necrosis factor-alpha (TNF alpha), soluble CD14 (sCD14), interferon-gamma (IFN gamma), GM-CSF, volume of urine and its pH. The clinical response was evaluated by urine histology and random quadrant biopsy 3 months after the start of therapy. Patients were divided into 2 groups, with good and poor therapeutic effect. The initial complete response rate was 62% (21/34). The data base was analyzed using traditional multivariate statistical methods and a pattern recognition method which deals with combinatorial-statistical analysis (statistically weighted syndromes (SWS) method) of the gradated features. The SWS method is capable of identifying robust patterns in small "fuzzy" sets with high dimensional objects and some missing values. RESULTS: Only one parameter gave significant differences at p < 0.05, GM-CSF at instillation 6. Repeated measurement analysis of variance, backward stepwise multiple logistic regression and linear discriminant analysis failed to show any significance. However, significant differences in the structure of correlation between features in the groups with and without therapeutic effect were observed and four highly informative variables (the masses of sICAM-1, TNF alpha, sCD14 and pH) relating to 5th-6th installations were selected by SWS. These features provided accurate individual prediction of therapeutic outcome for all our patients. Cross-validation analysis and computer simulation showed the statistically significant stability of the prediction. CONCLUSION: We have selected a set of urinary variables that could be considered as a perspective combination of indicators (syndromes) of outcome of pre-operation BCG therapy of patients with superficial bladder cancer. A larger patient database will provide testing and evaluation of the biological and clinical significance of selected features. The computational syndrome-disease approach should be applicable for the solution of decision-making problems for management of cancer.  相似文献   
55.
Dietary character of ruminants in the north is principally different between "nonselective" (cattle, sheep) and "selective" (reindeer, moose) species. Due to the developed polyfunctioning, forestomach in ruminants, primarily rumen and reticulum, are involved in the homeostasis formation in enteral and interior mediums, nutrients deposition and recirculation. That provides efficiency in utilization of deficient in nutrients forage and body reserves of wild ruminants during the winter. The original functional organization of absorption processes and nutrients recirculation across the multilayer epithelium of forestomach also promotes realization of the two levels metabolism during the year and adaptation of wild ruminants to season dynamics of nutrition.  相似文献   
56.
The paper analyzes the standard legal and methodological assurance of the quality and safety of animal food raw materials and foodstuffs (meat, meat products, fish, shellfish, crayfish and their processing products) by the parasitic purity rates according the requirements under the Russian Federation's laws "On Sanitary and Epidemiological Well-Being of the Population", "On Protection of Consumer's Rights", "On Certification of Products and Services", those of SanPiN, such as 2.3.2.560-96 "Sanitary Requirements for the Quality and Safety of Food Raw Materials and Foodstuffs" and 3.2.569-96 "Prevention of Parasitic Diseases in the Russian Federation".  相似文献   
57.
The study compared diagnostic potential of magnetocardiography (MCG), electrocardiography (ECG) and echocardiography (echo-CG) in 18 patients with arterial hypertension (AH). 32 healthy males served as control. Elements of MCG from normal subjects have been analyzed morphologically in 36 points of precordial leads. Left ventricular hypertrophy was registered at echo-CG, MCG, ECG in 11 (61%), 16 (84%) and 7 (34%) of the AH patients, respectively. Left atrial hypertrophy was discovered primarily by echo-CG and MCG. Defects in ventricular repolarization were recorded by MCg in 7 (39%) patients basing on MCG, echo-CG and rarely ECG signs of left ventricular hypertrophy. MCG is recommended as an effective tool in diagnosis of "hypertensive heart".  相似文献   
58.
The study of the functioning and development of the nervous system and its main structural-functional units, neurons, is a critical direction in modern medicine and neurobiology. The key stage in this process is analysis of neurons in microscopic images. The application of methods based on mathematical theory of pattern recognition and image analysis creates wide novel possibilities for analyzing similar representations of experimental data. The question on creating reliable automated systems for recognition and analysis of histological specumens remains, however, open. In the survey, we present results of an analysis of the methods and systems meant for automated neuron image analysis based on studies published in leading scientific journals within the past 25 years.  相似文献   
59.
The likelihood approach based on the empirical distribution functions is a well-accepted statistical tool for testing. However, the proof schemes of the Neyman–Pearson type lemmas induce consideration of density-based likelihood ratios to obtain powerful test statistics. In this article, we introduce the distribution-free density-based likelihood technique, applied to test for goodness-of-fit. We focus on tests for normality and uniformity, which are common tasks in applied studies. The well-known goodness-of-fit tests based on sample entropy are shown to be a product of the proposed empirical likelihood (EL) methodology. Although the efficiency of test statistics based on classes of entropy estimators has been widely addressed in the statistical literature, estimation of the sample entropy has been not invariantly defined, and hence this estimation produces tests that are difficult to be applied to real data studies. The proposed EL approach defines clear forms of the entropy-based tests. Monte Carlo simulation results confirm the preference of the proposed method from a power perspective. Real data examples study the proposed approach in practice.  相似文献   
60.
From the editors     

Proceedings of the 7th International Conference on Pattern Recognition and Image Analysis: New Information Technologies (PRIA-7-2004)18–23 October, 2004, St. Petersburg, Russian Federation Revised papers

From the editors  相似文献   
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