Impact on predictability of tropical and mid-latitude cyclones by extra Arctic observations.

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.

Optical particle-sizing method that provides optical isolation of the sampling volume.

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.

[Seasonal fluctuations of intraoperative blood loss in hip joint replacement].

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.

Wavelet-based vector quantization for high-fidelity compression and fast transmission of medical images.

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.