Fuzzy methods in tremor assessment, prediction, and rehabilitation.

Tremor is a disabling condition for a large segment of population, mainly elderly. To the present date, there are no adequate tools to diagnose and help rehabilitation of subjects with tremor, but recently there is a tremendous surge of interest in the research in the field. We report on the use of fuzzy methods in applications for rehabilitation, namely in tremor diagnosing and control. We synthesize our results regarding the characterization of the tremor by means of nonlinear dynamics techniques and fuzzy logic, and the prediction of tremor movements in view of rehabilitation purposes. Based on linear and nonlinear analysis of tremor, and using fuzzy aggregation, the fusing of tremor parameters in global functional disabling factors is proposed. Nonlinear dynamic parameters, namely correlation dimension and Lyapunov exponent is used in order to improve the assessment of tremor. The benefits of the fuzzy fused tremor parameters rely on more complete and accurate assessment of the functional impairment and on improved feedback for rehabilitation, based on the fused parameters of the tremor. Further steps in rehabilitation may require external muscular control. In turn, the control of tremor by electrical stimulation requires movement prediction. Several neural and neuro-fuzzy predictors are compared and a neuro-fuzzy predictor is presented, allowing us five-step ahead prediction, with an RMS error of the order of 10%. The benefits of the neuro-fuzzy predictor are good prediction capability, versatility, and apparently a high robustness to individual variations of the tremor. The reported research, which extended over several years and included development of sensors, equipment, and software, has been aimed to development of products. The results may also open new ways in tremor rehabilitation.

Techniques for evidencing the respiratory patterns and their temporal shift.

To enhance the efficiency of de visu or automatic detection and analysis of of the respiratory patterns, new techniques are introduced to process the respiratory signals. These techniques include: the dynamical frequency analysis, spectral envelope detection, three-dimensional representation of the spectral envelopes, and the 'respirogram'.

[Viral pollution studies of water environments]. / Etudes sur la pollution par des virus de certains milieux hydriques.

Virus pollution was studied in 734 water samples collected from the Dîmbovita River (310), lakes inside the town of Bucharest (136) and swimming pools (288). The results showed that the works carried out these last years to regularize the Dîmbovita led to a reduction of the virus pollution rate from 16.6-26.9% in 1984 to 4.16-5% in 1988. As for the lake and swimming pool waters, the pollution rate is directly proportional to the applied general hygiene measures. In summer, in drained lakes strictly controlled from the domestic and industrial sewage discharge point of view, the pollution rate was no higher than 6%, while in the lakes receiving sewage the frequency of isolations was between 12.5 and 18.75%. The same situation was found for swimming pools. A microepidemics of blepharoconjunctivitis was recorded in 1988 at a sport base: viruses were isolated from 20% of the water samples collected from its swimming pool, while virus pollution was about zero in the swimming pool water of some big hotels in Bucharest.

Frequency analysis of the acoustical respiratory response.

The frequency-domain analysis of respiration is used to put in evidence the respiratory reflexes, mainly the acoustical respiratory reflex. Based on the envelope of the spectrum, numerical parameters of the respiration are introduced and applied to determine respiratory patterns. The use of respirograms is also suggested.

Prevalence of antiviral antibodies in workers handling wastewater and sludge.

Serological investigations were performed between 1977-1978 with 972 serum samples from 243 subjects having either direct (group A) or sporadic (group B) occupational contact with wastewater or sludge. the control group (C) was represented by 100 persons having no contact with such material. The sera were tested against influenza, parainfluenza, adeno-, herpes, coronavirus, rickettsial and chlamydial antigens, as well as for the presence of HBsAg and anti-HBs. Statistically significant differences between group A and groups B and C were found as regards the prevalence of antibodies to adenovirus and parainfluenza virus type 1 antigens.

[Complications of Crohn's disease (Clinical and anatomopathological observations on 13 cases)]. / Complicatiile bolii Crohn (Observatii clinice si anatomopatologice pe 13 cazuri)

Malignization of Crohn disease remains the most severe complication, both due to its intrinsic gravity and to the major complications that it may induce such as: peritonitis--following suppurations and perforation of the involved intestinal segment; intestinal sub-occlusion or mechano-inflammatory occlusion, either tumoral or chronic leading to stenosis of the intestine; hemorrhage. Malignization of Crohn disease was found in 53,84% of the cases (7 out of a total of 13 cases, between 1968 and 1974). This allows to conclude that Crohn disease can be considered as a pre-cancerous disease.