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Introduction. In sheet and hull structures operating under pressure, destruction, as a rule, is localized along the transition line from the base metal to the weld metal. Methods of increasing the durability of butt-welded joints, which are aimed at reducing stress concentration and creating favorable residual compression stresses, are described.Materials and Methods. The tests were carried out on an installation for biaxial bending, which created a biaxial stress field. Factory-made coupons and samples with an additionally processed transition zone from the weld metal to the base metal were tested. The effectiveness of further processing is shown by the following methods:– abrading;– grit hardening;– abrading with grit hardening;– melting of the fusion line in argon without filler wire;– melting of the fusion line in argon with filler wire EP-410U;– melting of the fusion line without filler wire with plastic deformation between narrow rollers.Results. The origin, development of destruction, and its features were analyzed using different methods of further processing of joint welds. Confidence spans (95 %) of the origin and development of failures for joint welds and base metal were calculated. The efficiency of the proposed methods for further processing was evaluated.Discussion and Conclusions. An analysis of the effectiveness of methods for increasing the durability of butt-welded joints has shown that the creation of a smooth transition from the weld metal to the base metal reduces significantly the stress concentration. This provides increasing the number of cycles before the onset of destruction and the survivability of compounds. Due to compressive stresses in the near-weld area, it is possible to increase the durability of joint welds. The most effective methods of further processing of welds combine the reduction of stress concentration and the creation of residual compression stresses. The high-tech solution is remelting the transition zone in an argon medium with an additional EP-410U filler wire.

The article consists of two parts. The first is dedicated to the 500th anniversary of Conrad Gessner (1516-1565), an outstanding Swiss scholar and bibliographer. He entered the history of bibliography and librarianship as a compiler of «Bibliotheca Universalis» published in 1545 at Christopher Froshower’s Printing House in Zurich. «Bibliotheca Universalis» is the first attempt to create an international bibliography of books printed in Greek, Latin and Judish, as well as biographical information about authors and their writings. In total, he described about 15,000 books belonging to almost five thousand authors. Over 12,000 books were systematized according to 21 sections (pandects), which had more than 250 subject-thematic headings. Particular attention is paid to the analysis of the bibliographic language of «Bibliotheca Universalis». The second part of the article contains a description of the jubilee events dedicated to Conrad Hessner. They were the following: 1916 - the 400th anniversary celebration in Chicago; 1965 - meeting in Oxford, and 2016 - program of events in Switzerland.

The main problems of home bibliography are analyzed.

Aim. To study risk factors (RF) of acute myocardial infarction (AMI), their significance and interplay in a “closed” population – people with chronic low-dose ionizing radiation (IR) exposure at their workplace. Material and methods. According to WHO AMI Registry, 1 370 AMI cases were analyzed, including 327 cases in people exposed to long-term low-dose IR at their workplace. A prospective cohort study of AMI morbidity in a “closed” population (1998-2002) was performed. Results. It was demonstrated that total dose of external radiation, duration of working in radiation-dangerous environment, and traditional cardiovascular RF, were independently distributed in IR-exposed AMI patients. Maximal total doses of external radiation were registered in young AMI patients. Individual dose negatively correlated with arterial hypertension (AH) duration before AMI development. Conclusion. Among persons with long-term IR exposure, psycho-emotional stress, smoking, and AH were the leading cardiovascular RF in AMI pathogenesis. Long-term, low-dose IR enhanced traditional cardiovascular RF (dyslipidemia, AH) aggression in AMI pathogenesis.