Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrankheiten und Hygiene. Erste Abteilung Originale. Reihe B: Hygiene, Betriebshygiene, praventive Medizin最新文献

Dehydrogenase activity of activated sludges coming from a laboratory plant, has been evaluated by the TTC-test in the presence of some chemical toxics. The results obtained have shown that, for all inhibitors tested, there exists a range of concentrations in which the dose-response relationship is linear. As far as the comparison of the inhibition data from the TTC-test and from the Oxygen-respiration rate is concerned, the results obtained show that the inhibitors tested may be divided into three groups: (i) inhibitors which inhibit the Oxygen-respiration rate more than th Dehydrogenase activity (Zn2+, Cd2+, Ni2+, Hg2+, Zn(CN)4(2-), Cd(CN)4(2-)); (II) inhibitors for which there are no significant differences in the inhibition value obtained by the two methods (CN-, C6H5O-, C6Cl5O-, C6H3ClO-, Hg(CN)4(2-)); (iii) inhibitors which inhibit the dehydrogenase activity more than theoxygen-respiration rate (Cu2+, CrO4(2-), Ni(CN)4(2-)). The inhibition data obtained by other authors evaluating by direct methods (COD reduction, turbidity of the final effluent etc.) the performance of pilot or laboratory plants in the presence of some of the toxics used in the present research, are in sufficient agreement with the dehydrogenase inhibition data obtained in this work.

The investigations concerning the influence of supply-frequent electric fields on man have been carried out on 12 subjects in 24 single trials. A field intensity as it occurs in the height of the subjects' head under a 380 kV high voltage transmission line was used. Some physiological parameters like ECG, EEG, blood pressure, blood gas and reaction time have been recorded and analyzed. The parameters were both analogously recorded and digitally stored as indicated in Fig. 2. Some of the investigations were carried out under mental load of the subjects and showed that the changes in the heartrate due to this load cover the switch-off effect of the heartrate. For the other parameters like EEG, reaction time, blood gas and blood pressure no influence of the investigated field intensity on man could be found.

Before the start of a research project which was to stretch over a period of several years, characteristics of the control space were to be defined. Therefore the influence of spherics and 50 Hz-alternating fields in the unscreened control space were studied.--Pupils (Foster children) were the test subjects. Each test subject was subjected to the conditions of the control space as well as the testing space.--Two classes of parameters were studied. Blood sugar, blood pressure and pulse rate were recorded as physiological dimensions. Short-term memory, powers of concentration as well as the subjective well-being were the psychological parameters.--As to the parameters examined, no significant difference between testing and control space conditions was recorded. In order to examine whether the climatic factors of the control space have an antagonistic effect on the variables in question, their influence was studied separately in two further investigations. In order to clarify this problem, spherics-impulses in the 10 Khz range were given in screened space ("Vorversuch 2"/preliminary experiment 2), then--in, "Vorversuch 3"/preliminary experiment 3 - a 50 Hz-alternating field was applied. For each of the climatic factors under examination the influence on each single parameter was negative. The assumption of an antagonistic effect which would hinder the definition of standard spatial conditions was thereby shown to be incorrect.

The Electroaerosoltherapy (EAT) has got a world-wide diffusion especially in diseases of the respiratory system. The unipolary negatively charged aerosols are very steady and penetrate deeply into the respiratory tract. The ciliary activity is stimulated, the mucus liquified and the bronchial spasms relaxed. The author use a table-apparatus (Barthel-Küster System), which allows the simultaneous therapy, and a combination from an Ionogenerator with a portable aerosol generator (air ion transmitter needle into the aerosol mask). The EAT has no noxious secondaries effects.

Experiments were done about the behaviour of 5 different strains of Staph. aureus, Strept. faecalis, E. coli, Ser. marcescens and P. aeruginosa in aqua bidest and sterile tap water at 20 degrees C, 30 degrees C and 40 degrees C. The behaviour of 3 different initial colony counts in each case was examined. Colony forming units (CFU) were evaluated at the beginning and after 1, 2, 4, 6 and 24 h. CFU were reduced at Staph. aureus and E. coli in aqua bidest and tap water not earlier than after 4 h, but mostly after 24 h. In Strept. faecalis CFU were reduced in aqua bidest at 40 degrees C after 24 h, in tap water at 40 degrees C after 4 h, but there were no changes of CFU in both media at 20 degrees C or 30 degrees C. Ser. marcescens strains were growing in aqua bidest and tap water after 24 h at 20 degrees C. P. aeruginosa strains were reduced in aqua bidest at all temperatures but they were growing in tap water after 24 h. Reduction or growth of all strains did not depend on initial colony count during examination time, changing of CFU turned out to be quicker at 40 degrees C than at 20 degrees C. It is the conclusion that in humidifiers and nebulizers CFU will be different from initial colony count not earlier than after 6 h. Growth will be seen after 6 until 24 h if there are no particular nutritive organic compounds.

The results of microbiological and chemical examinations of water samples collected from hydrotherapy pools for non incontinent patients proved that the officially agreed parameters for the surveillance of public swimming pools (Osterr. Bäderhygiene-Gesetz and Verordnung) have to be extended to meet the requirements of epidemiology. Similarly the requirements for treatment and operating conditions of those waters should be more rigorous. Minimal requirements for the treatment of water in hydrotherapy pools are recommended. The results of the study indicated also that the microbicide action of chlorine (chlorine gas, hypochlorite solution) was superior to those of DIHALO (chlorine-bromine-hydantoine). Suggestions are made for proper handling of waters which would lose their therapeutical potencies by any kind of treatment.

From a sample of non-treated, non chlorinated well water a Yersinia pseudotuberculosis II strain was isolated. The water had been apparently massively contaminated because the strain was isolated from 1 ml of the sample. The serotype II of Y. pseudotuberculosis occurs very rarely as aetiological agent of human and animal infections.

Aquatic myxobacteria were shown to be good indicators of surface contamination of drinking water, or water filtered by an inadequate soil profile, both in experiments with sterilized or biologically active soil profiles, resp., and in actual comparison data obtained in practical drinking water analyses. In experimental investigations with artificial profiles, aquatic myxobacteria were retained to a considerably greater degree than E. coli or P. fluorescens due to stronger forces of adhesion. In a number of bacteriological drinking water analyses, this property was confirmed insofar as aquatic myxobacteria could regularly be demonstrated when inspecting hygienically deficient wells or springs. The confirmed presence of E. coli, on the other hand, showed a considerably lesser correlation with the results of on the spot evaluations of hygienic conditions. It must be urgently advised to include the search for aquatic myxobacteria in bacteriological drinking water analyses, since, contrary to the demonstration of E. coli, not only the actual but, in addition, the potential hazard of contamination of drinking water with bacteria present in superficial soil strata is indicated.

Weather situations connected with small pressure gradients show a statistically significant correlation with the liability to heart-attacks. Changes from cyclonic to anticyclonic situations with descending air-motion lead to a rise of the number of heart-attacks in summer. In winter the change from anticyclonic to cyclonic pressure distributions seems to be critical.