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Recent research has demonstrated that additional winter radiosonde observations in Arctic regions enhance the predictability of mid-latitude weather extremes by reducing uncertainty in the flow of localised tropopause polar vortices. The impacts of additional Arctic observations during summer are usually confined to high latitudes and they are difficult to realize at mid-latitudes because of the limited scale of localised tropopause polar vortices. However, in certain climatic states, the jet stream can intrude remarkably into the mid-latitudes, even in summer; thus, additional Arctic observations might improve analysis validity and forecast skill for summer atmospheric circulations over the Northern Hemisphere. This study examined such cases that occurred in 2016 by focusing on the prediction of the intensity and track of tropical cyclones (TCs) over the North Atlantic and North Pacific, because TCs are representative of extreme weather in summer. The predictabilities of three TCs were found influenced by additional Arctic observations. Comparisons with ensemble reanalysis data revealed that large errors propagate from the data-sparse Arctic into the mid-latitudes, together with high-potential-vorticity air. Ensemble forecast experiments with different reanalysis data confirmed that additional Arctic observations sometimes improve the initial conditions of upper-level troposphere circulations.

Under analysis was the level of intraoperative blood loss in total endopropsthesis of the hip joint in 513 patients operated upon for degenerative-dystrophic processes of consequences of trauma in the period from 1996 to 1999. The assessment of seasonal variations of its value was made. It was shown that the volume of blood loss is dependent on two groups of factors: medical and associated with the influence of the environment. The least "chronorisk" of excessive blood loss was noted in the period from July to November, the greatest--from January to June (with the maximum in March and reduction in May).

We have constructed and tested a novel particle sizer that employs particle counting (the time-domain approach) rather than the ensemble-diffraction approach that currently dominates the market in atmospheric-dust particle sizers. The method does not depend on mechanical devices to restrict particles within the sampling volume but instead allows for optical isolation of the sampling volume. This technique is useful for atmospheric-dust measurements for which nonobtrusive measurement is often desirable.

Compression of medical images has always been viewed with skepticism, since the loss of information involved is thought to affect diagnostic information. However, recent research indicates that some wavelet-based compression techniques may not effectively reduce the image quality, even when subjected to compression ratios up to 30:1. The performance of a recently designed wavelet-based adaptive vector quantization is compared with a well-known wavelet-based scalar quantization technique to demonstrate the superiority of the former technique at compression ratios higher than 30:1. The use of higher compression with high fidelity of the reconstructed images allows fast transmission of images over the Internet for prompt inspection by radiologists at remote locations in an emergency situation, while higher quality images follow in a progressive manner if desired. Such fast and progressive transmission can also be used for downloading large data sets such as the Visible Human at a quality desired by the users for research or education. This new adaptive vector quantization uses a neural networks-based clustering technique for efficient quantization of the wavelet-decomposed subimages, yielding minimal distortion in the reconstructed images undergoing high compression. Results of compression up to 100:1 are shown for 24-bit color and 8-bit monochrome medical images.

The review shows the basic stages of development of aerospace toxicology. It traces the way of forming this research direction from its origin to the present day. Study methods are being improved as practical tasks are becoming more intricate. The names of the Institute's employees who take an active part in the development of this problem and the advances made are enlisted. The results of researches are summed up and further trends are outlined.

The literature data pointing to the fact that man can actively adapt to the effect of chemical substances at doses not exceeding hygienic norms are presented. However using some medical measures it is possible to increase to some extent the body resistance to the effect of chemical impurities of the environment and thus delaying for some time the development of disadaptation disorders induced by these impurities.