Monitoring, removal and risk assessment of cytostatic drugs in hospital wastewater.

Cytostatic agents are applied in cancer therapy and subsequently excreted into hospital wastewater. As these substances are known to be carcinogenic, mutagenic and toxic for reproduction, they should be removed from wastewater at their source of origin.In this study the fate and effects of the cancerostatic platinum compounds (CPC) cisplatin, carboplatin, oxaliplatin, 5-fluorouracil (5-FU) and the anthracyclines doxorubicin, daunorubicin and epirubicin were investigated in hospital wastewater. Wastewater from the in-patient treatment ward of a hospital in Vienna was collected and monitored for the occurrence of the selected drugs. A calculation model was established to spot the correlation between administered dosage and measured concentrations. To investigate the fate of the selected substances during wastewater treatment, the oncologic wastewater was treated in a pilot membrane bioreactor system (MBR) and in downstream advanced wastewater treatment processes (adsorption to activated carbon and UV-treatment). Genotoxic effects of the oncologic wastewater were assessed before and after wastewater treatment followed by a risk assessment.Monitoring concentrations of the selected cytostatics in the oncologic wastewater were in line with calculated concentrations. Due to different mechanisms (adsorption, biodegradation) in the MBR-system 5 - FU and the anthracyclines were removed < LOD, whereas CPC were removed by 60%. In parallel, genotoxic effects could be reduced significantly by the MBR-system. The risk for humans, the aquatic and terrestrial environment by hospital wastewater containing cytostatic drugs was classified as small in a preliminary risk assessment.     

Technological prediction as a means of identifying additional competitive advantages of a specific production process

Results are presented from predictions of the quality indices of metal products used in critical applications. The predictions are obtained for combinations of technological factors that are not used in the actual production process. The reliability of the predictions is confirmed by the fact that the index values obtained with the use of regression models agree with the values obtained using corresponding genetic algorithms. The advantages of the methodology described in the article are demonstrated using the example of analysis of the multi-stage cold rolling of tubes made of zirconium alloys. The introduction of procedures for making technological predictions will help make production processes more efficient and, thus, more competitive. __________ Translated from Metallurg, No. 2, pp. 31–36, February, 2007.     

Heat transfer enhancement by oscillatory perturbation of a stable separated flow

Numerical and experimental results for laminar flow and forced convection in a grooved channel indicate that significant heat transfer enhancement is possible by appropriately-tuned modulation of a steady, separated flow. The frequency r response of the enhancement is strongly peaked around the frequency of the least stable (decaying) mode of the unmodulated flow, suggesting that a simple resonance phenomenon is responsible for the transport augmentation.     

General solution of one-dimensional,time dependent coupled heat flow systems

A new, powerful method of analysis, involving the combined use of finite integral transform and finite element techniques, is presented for the solution of time dependent heat flow systems composed of many one-dimensional elements connected through the nodes. This method leads to an eigenvalue problem which is not of the conventional Sturm-Liouville type. A procedure for the determination of the eigenvalues is described. The solution obtained is in the form of an infinite series and contains quasi-steady and transient terms. The general solution obtained can be applied in the mathematical modelling of many engineering applications such as the determination of the penetration of the daily temperature cycle into buildings, the analysis of heat transfer in array of extended surfaces in compact heat exchangers, and many others.     

Gamma-Irradiation of Frozen Kiwifruit Pulp

Frozen (–18°C) de-seeded kiwifruit pulp (Actinidia deliciosa) was irradiated at a dose of 100 krad and stored at -18°C. Irradiation resulted in a 2.11 log₁₀ reduction in aerobic plate count (APC) with bacteria being most susceptible. Molds were less susceptible than yeasts. Assessments carried out over 6 months storage showed no significant differences in physical, chemical and sensory properties between irradiated and nonirradiated pulps. The microbial populations of the pulps decreased in parallel throughout the storage period. Frozen storage without irradiation resulted in a 3 log₁₀ reduction in APC over the 6 months period, a 38% reduction in ascorbic acid, and a slight loss of color. Three days frozen storage (– 18°C) following irradiation resulted in an APC only 0.89 log₁₀ higher than 6 months frozen storage (- 18°C) without irradiation with potential savings in energy and holding times which could have economic benefits.     

Effect of vitamins A, E and K on the indices of the glutathione antiperoxide system in gingival tissues in periodontosis

Glutathione reductase is activated and the content of glutathione sulfhydryl groups is increased in the gingival tissue of patients afficted with parodontosis. The degree of alterations depends on the degree of the development and character of the disease. Application of antioxidant vitamin therapy (vitamins A, E and K) locally and per os normalizes the parameters under study and improves the status of the parodontium.     

Near-field optical imaging of unstained bacteria: comparison with normal atomic force and far-field optical microscopy in air and aqueous media

Simultaneous near-field scanning optical and atomic force imaging of bacteria is presented. The bacteria imaged in these studies were unstained. The near-field optical images had excellent signal-to-noise and showed excellent contrast even in these unstained specimens. The images obtained were interpreted in terms of the images that have been obtained by transmission electron microscopy and X-ray imaging. The results show that bacterial near-field optical imaging is going to be a very important tool in the arsenal of the bacteriologist both in terms of understanding the fundamental processes in the life cycle of bacteria with and without cytochemical staining and in terms of clinical diagnostic applications.