ROUGH SET REDUCTION OF ATTRIBUTES AND THEIR DOMAINS FOR NEURAL NETWORKS

This paper presents an empirical study of the use of the rough set approach to reduction of data for a neural network classifying objects described by quantitative and qualitative attributes. Two kinds of reduction are considered: reduction of the set of attributes and reduction of the domains of attributes. Computational tests were performed with five data sets having different character, for original and two reduced representations of data. The learning time acceleration due to data reduction is up to 4.72 times. The resulting increase of misclassification error does not exceed 11.06%. These promising results let us claim that the rough set approach is a useful tool for preprocessing of data for neural networks.     

Natural cytotoxicity of CD16+ lymphocytes in women with selected states of pregnancy pathology

The natural cytotoxic activity of lymphocytes CD16+ (NK) was studied in healthy nonpregnant and pregnant women and in patients with threatened spontaneous abortion, preterm delivery and preeclampsia. We have shown no differences in the proportion of NK cells between all studied patients and controls. The possibility of previous contact with embryonic antigens was excluded since no differences were noted between cytotoxic activity of NK cells obtained from multiparous women and those who never gave a birth. The natural cytotoxic activity of NK cells from patients with threatened abortion or preterm delivery was found to be significantly higher (p < 0.01) than from cells of healthy pregnant women. However in preeclamptic patients activity of NK cells was very low as comparing to pregnant women and more than three lower than in nonpregnant ones. This indicates that though the amount of NK cells does not different between normal and pathological pregnancies, there is marked difference in their biological activity.     

Exercise echocardiography with left atrial stimulation: advantages and limitations of the method

Exercise echocardiography seems a relatively reliable diagnostic technique for evaluation of patients with coronary artery disease. The prognostic aspects of the stress echo have widely been documented with the use of various stressors (exercise, dipyridamole, dobutamine, pacing). Rapid atrial pacing echocardiography is highly specific and sensitive technique for the detection of the coronary disease, especially in patients who are unable to perform an active stress test. This technique minimizes the factors decreasing image quality during exercise (chest wall movements and hyperventilation). Exercise echocardiography is safe, relatively cheap, and can be done in every hospital.     

The hepatoprotective and hyoplipidemic effect of flower pollen lipid extract in androgenized rats

Hepatoprotective, hypolipidemic and hypocholesterolemic effects of the lipid flower pollen extract in subchronically testosterone-androgenized rats were shown. Normalization of AspAT, A1AT and alkaline phosphatase--biochemical indicators of necrotic changes in the hepatic cell--substantially testifies to the hepatoprotective effect of the investigated lipid flower pollen extract on the hepatic cell, and constitutes a premise for further clinical studies.     

Lipid-lipoprotein serum profile of the newborn and its birth weight

The sixty-seven newborns were investigated. The umbilical cord blood samples were used to determine following indices: total cholesterol, LDL, HDL2, HDL3-cholesterol, total phospholipids, LDL, HDL-phospholipids, triglycerides and apolipoprotein B. The chi 2 test indicated correlations between increased levels of triglycerides, phospholipids LDL and cholesterol HDL2 and decreased level of cholesterol LDL in the group of newborns with the lowest delivery body mass.     

Concentration of lipids and lipoproteins in serum of pregnant women with primary hypertension

The tests have been conducted on 44 women in 3rd trimester of pregnancy. 30 of them were the women with a normal course of pregnancy, and 14 were the ones with the primary hypertension. The blood serum has been tested for the concentration of triglycerides, phospholipids, total cholesterol, HDL and LDL- cholesterol, alpha, beta and pre-beta lipoprotein fractions. The results have been calculated statistically. It has been found that the increase in the concentration of triglycerides (p < 0.001), and the beta lipoprotein fraction (p < 0.004) was essentially higher in the women with the primary hypertension in 3rd trimester of complicated pregnancy in comparison to those values observed in the healthy pregnant women. At the same time a lower concentration of alpha lipoproteins (p < 0.02) has been observed in the group of the pregnant with the primary hypertension. Differences between the concentration of other parameters have not obtained statistical significance.     

Subglottic tracheal stenosis in Wegener''s granulomatosis. Report of 3 cases]

OBJECTIVE: This study was performed to assess whether coadministration with grapefruit juice significantly affects the pharmacokinetics of amlodipine, a dihydropyridine class calcium antagonist with slow absorption, distribution and low plasma clearance. The primary objective was to evaluate whether short exposure to grapefruit juice could affect the metabolism of amlodipine to an extent similar to that previously demonstrated for other dihydropyridines (e.g. felodipine, nisoldipine, nitrendipine). METHODS: Twelve healthy male volunteers followed a randomised, open crossover study design, comparing the effect of a single oral dose of amlodipine (5 mg) taken together with a glass of grapefruit juice (250 ml) vs water. Blood samples to determine plasma concentration were taken and blood pressure (BP) and heart rate (HR) were measured throughout the study. RESULTS: When amlodipine was coadministered with grapefruit juice, Cmax was 115% and AUC(0-72 h) was 116% compared with water, but tmax was not significantly changed. There were no significant differences in BP and HR between the two treatments. A small decrease in diastolic BP, however, was observed in both treatments 4-8 h after drug administration, coinciding with Cmax, but this was normalised after 12 h. The BP reduction seen was compensated by a slight increase in HR, which remained throughout the study. CONCLUSION: An interaction between grapefruit juice and amlodipine was demonstrated. The haemodynamic data showed that a dose of 5 mg was sufficient to achieve a BP reduction in healthy subjects, but the increase in amlodipine plasma concentration seen after intake of grapefruit juice was too small to significantly affect BP or HR. The clinical significance of this food/drug interaction, however, cannot be ignored since there is considerable variation between individuals and a more extensive intake of grapefruit juice might give more pronounced effects.     

On the formation of liquid inclusions in some solution-grown crystals: (I) sodium-cadmium formate

The formation of liquid inclusions in sodium-cadmium formate (SCF) single crystals has been studied. Crystals were grown on seeds by slow cooling of unstirred aqueous solution. It was found that liquid inclusions in SCF are a result of convective flow around a crystal. The results are briefly analysed from theoretical considerations.     

Sleepers and workaholics: Caching strategies in mobile environments (Extended version)

In the mobile wireless computing environment of the future, a large number of users, equipped with low-powered palmtop machines, will query databases over wireless communication channels. Palmtop-based units will often be disconnected for prolonged periods of time, due to battery power saving measures; palmtops also will frequently relocate between different cells, and will connect to different data servers at different times. Caching of frequently accessed data items will be an important technique that will reduce contention on the narrow-bandwidth, wireless channel. However, cache individualization strategies will be severely affected by the disconnection and mobility of the clients. The server may no longer know which clients are currently residing under its cell, and which of them are currently on. We propose a taxonomy of different cache invalidation strategies, and study the impact of clients' disconnection times on their performance. We study ways to improve further the efficiency of the invalidation techniques described. We also describe how our techniques can be implemented over different network environments.