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The article deals with the state-of-the-art in the field of Longitudinal critically refracted (LCR) ultrasonic wave, for non-destructive material evaluation. It checks its capability for residual stress identification, and reviews positives and negatives related to its use. Obtained information within the article, are used for the understanding of essence of method and for the evaluation of its use in the engineering practice. The article can be the source of information about the LCRwave measurement technology, which is the part of the complex ultrasonic testing method. For the frequency of using this technology for surface residual stress measurement, it is appropriate to have this information in one whole, which are gathered of the outputs of researches by various authors. The paper is divided in few sections and sub-sections. In the first section, information about LCRwave technique and factors correlated with this method, are provided. The next section writes about residual stresses and the importance of their identification. Next, the principal of residual stresses measurement and basic structure of measurement device, is described. A significant part of study, describes the state so far of theoretical and practical researches within the use of this method, in the technological practice of residual stress identification in surface layers of engineering components. In the conclusion, obtained knowledges are summarised and evaluated. Related positive and negative aspects are included, with a verifying the need of future researches.

Summary The therapeutic efficacy of gentamicin given once or three times a day was compared in a model of experimental renal infection in rats. The same amount of gentamicin given either in a single injection or three injections a day produced no statistically significant difference in the treatment of incipient infection. The effect of this mode of administration on advanced infection depended on the length of the therapy. After five days, administration of the same dose given in a single injection or three injections did not result in significant differences. After ten days the therapy proved more effective when gentamicin was injected three times a day. In comparison a single daily dose, amounting to two thirds of the total dose when given three times a day every eight hours, revealed after five days of therapy a statistically significantly lower bacterial count in the kidney than three daily injections of gentamicin.

Presented paper is focused on knowledge in the field of tube drawing process. The introduction consists of summarizing the current state of the art. In the material and methods section, it is a characteristic of the usability of rifled tubes for heat exchangers, which serve to better heat exchange between the medium and the tube. The following section describes the implementation of the experiment. This section shows the principle of pipe drawing using a grooved mandrel and a die. The result section is showing resulting a simulation of strength analyzes and the recorded values during the pulling tests. In conclusion, the aim of this paper is briefly explained, as well as the need to take into account the leading part of the mandrel, which may result in incorrect geometry and cavitation. In conclusion, the issue is mentioned, which is beneficial for science and research in the field of cold drawing of tubes. It is also about knowledge with internally shaped surface in energetic equipment.

Summary A group of 44 patients with various clinical forms of urinary tract infections received a single dose of 300 mg netilmicin i.m. The treatment was efficacious in all patients with infections which were negative in the antibody-coated bacteria test and not complicated by anatomic and/or functional abnormalities of the kidneys and urinary tract. After three weeks the recurrence rate was only 19%. Single-dose treatment also proved very effective against urinary tract infections in renal transplant patients whose infection is almost always located in the lower urinary tract. In contrast, the short-term results of treatment were much poorer in complicated infections and particularly in urinary tract infections which were positive in the antibody-coated bacteria test; here, the recurrence rate was 67%.

Summary Twenty-three patients with various types of recurrent urinary tract infection were treated with a single daily dose of 160 mg gentamicin for eight to nine days. The treatment eliminated bacteriuria in 19 patients. Evaluation of the therapeutical results according to the site of infection showed elimination of bacteriuria in all patients with lower urinary tract infection. Thus a single daily dose of gentamicin can be recommended in recurrent lower urinary tract infection, and also in upper urinary tract infection not associated with a major impairment of renal function.

The relationship between the elimination constant of gentamicin and the percentage of functioning nephrons in rats cannot be characterized by a simple linear relation. The results support the assumption that gentamicin elimination per residual nephron increased.