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Protection of Metals and Physical Chemistry of Surfaces - The nanocrystalline tantalum alloys were investigated in terms of mechanical properties. The materials were obtained by powder metallurgy...  相似文献   
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Image sequences processing and video encoding are extremely time consuming problems. The time complexity of them depends on image contents. This paper presents an estimation of a block motion method for video coding with edge alignment. This method uses blocks of size 4 × 4 and its basic idea is to find motion vector using the edge position in each video coding block. The method finds the motion vectors more accurately and faster than any known classical method that calculates all the possibilities. Our presented algorithm is compared with known classical algorithms using the evaluation function of the peak signal-to-noise ratio. For comparison of the methods we are using parameters such as time, CPU usage, and size of compressed data. The comparison is made on benchmark data in color format YUV. Results of our proposed method are comparable and in some cases better than results of standard classical algorithms.  相似文献   
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In patients with progressive systemic sclerosis (PSS) suffering from chronic dyspepsia the stomach may be affected by this disease. The objective of this study was to investigate both antral myoelectrical activity and gastric emptying in PSS patients. Electrogastrography (EGG) was performed in 17 PSS patients (16 female, one male, median age 58 years, range 32-74 years) with chronic dyspepsia. After an overnight fast during one hour in the fasting and one hour in the fed state after ingestion of a liquid-solid test meal (370 kcal; liquid phase labeled with 0.5 mCi 99mTc-colloid) antral electrical activity was measured by one pair of electrodes sonographically placed on the skin overlying the gastric antrum. Several EGG parameters including dominant frequency (DF), percentages of DF in the normal range (2-4 cycles per minute [cpm]), bradygastria (< 2 cpm) and tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to preprandial power ratio (PR) were calculated. The data were correlated to results obtained in 20 age- and gender-matched healthy subjects. In addition, the data were compared to gastric retention of the radionuclide at 60 min measured by simultaneous scintigraphy. The PSS patients did not reveal electrical disturbances. They even exhibited a significant postprandial decrease in DFIC, bradygastria, and tachygastria (ns) compared to healthy subjects. Over 50% of the PSS patients showed a delayed gastric emptying. However, EGG did not correlate to radioscintigraphy significantly. Our results reflect an absent relationship between antral myoelectrical activity in EGG and gastric emptying. Therefore, electrogastrography is unsuitable to assess gastric involvement in PSS.  相似文献   
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BACKGROUND/AIMS: Chronic alcoholism is known to effect gastric motor activity. An association between gastric motility disorders and abnormal myoelectrical activity has been observed in various gastrointestinal and extra-intestinal diseases. The aim of this study was to investigate the effect of chronic alcoholism on gastric emptying and antral myoelectrical activity. METHODOLOGY: Electrogastrography (EGG) was performed on 20 chronic alcoholics with chronic dyspepsia using a pair of electrodes sonographically placed on the skin overlying the gastric antrum. After an overnight fast, patients were tested over a period of one hour in the a) fasting and b) fed state, after ingestion of a 370 kcal liquid-solid test meal. The following EGG parameters were determined: dominant frequency (DF (cpm); DF (%) in the normal range (2-4 cpm); bradygastria (<2 cpm); tachygastria (4-10 cpm); dominant frequency instability coefficient (DFIC), and postprandial to fasting power ratio (PR). The data were correlated with results obtained from 20 controls matched for age and sex. In 18 alcoholics, the EGG data were compared to the percentage of radionuclides (liquid phase labeled with 99m Tc colloid) remaining in the stomach after 60 minutes (%) (gamma camera system). Moreover, for the alcoholics, various parameters such as ethanol consumption, and gastrointestinal symptoms were determined and related to EGG values and scintigraphy. RESULTS: About 50% of the alcoholics showed delayed gastric emptying compared to normal values previously reported (t 60 values: >68%). In opposite to scintigraphy, the alcoholics did not exhibit abnormalities in antral myoelectrical activity. They had significantly decreased bradygastria measures compared to controls (p<0.05). The scintigraphic t 60 values did not correlate either with EGG values or with dyspepsia and clinical parameters. EGG values did not correlate with dyspepsia. However, increased preprandial DF was significantly correlated with ethanol consumption. CONCLUSIONS: Chronic alcoholism induces a disturbance of gastric emptying, probably resulting from toxic damage of the gastrointestinal smooth muscles. Disturbances in antral myoelectrical activity were not found.  相似文献   
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A category (of data types) is called algebraically ω-complete provided that for each endofunctor T the data-type equation T(X) X has a solution constructed as a colimit of the ω-chain → T() → T2()..., where is the initial data-type. Examples include the categories of (1) countable sets and (total, partial, or nondeterministic) functions, (2) countably dimensional vector spaces and linear functions, (3) countable well-ordered sets and join-preserving functions. In the case of categories enriched over CPO (the category of complete partial orders and strict, continuous functions) a stronger property holds for all locally continuous functors T: the data-type equation is both a limit and a colimit of the finite iterations of T over the initial data-type.  相似文献   
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A case of ankylosing spondylitis with pronounced osteolysis of the 12th thoracic vertebral body as part of posttraumatic pseudoarthrosis is described. The appearance of posttraumatic osteolysis simulates a malignant lesion, and it is important to consider the diagnosis in cases of osteolytic lesions of unknown origin.  相似文献   
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The mechanism of sulfisoxazole (SFF) selective removal by photocatalysis in the presence of titanium (IV) oxide (TiO2) and iron (III) chloride (FeCl3) was explained and the kinetics and degradation pathways of SFF and other antibiotics were compared. The effects of selected inorganic ions, oxygen conditions, pH, sorption processes and formation of coordination compounds on the photocatalytic process in the presence of TiO2 were also determined. The Fe3+ compounds added to the irradiated sulfonamide (SN) solution underwent surface sorption on TiO2 particles and act as acceptors of excited electrons. Most likely, the SFF degradation is also intensified by organic radicals or cation organic radicals. These radicals can be initially generated by reaction with electron holes, hydroxyl radicals and as a result of electron transfer mediated by iron ions and then participate in propagation processes. The high sensitivity of SFF to decomposition caused by organic radicals is associated with the steric effect and the high bond polarity of the amide substituent.  相似文献   
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