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Advanced oxidation processes, like UV/H2O2 oxidation, are important barriers against organic micro pollutants in drinking water treatment. In order to guarantee safe drinking water, it is important to be able to predict the reactors' performance to adjust the operating conditions to the actual influent water characteristics (like UV transmission) and lamp performance. Therefore, a design tool was developed, which is based on a kinetic model that describes and predicts the direct photolysis and oxidation of organic compounds in pilot experiments, using Low Pressure (LP) UV-lamps. This model has been combined with computational fluid dynamics (CFD), in order to be able to accurately predict the results of pilot and full scale installations, and also to design reactor systems. The model was applied to three model compounds (atrazine, ibuprofen and NDMA) in two different pilot reactors, and it has been shown that reactor performance can be fairly predicted by applying this 'UvPerox' model. The model takes into account the water quality and power of the lamps, and the properties of the compounds involved. [ABSTRACT FROM AUTHOR]

Water treatment in The Netherlands has developed to an outstanding level. Nevertheless, new challenges, such as protozoa (e.g. Cryptosporidium), Legionella, endocrine disrupting compounds and pharmaceuticals, have to be faced. These challenges can have a negative effect on customer confidence and the overall reputation of water supply. The Dutch water supply companies therefore have set a new ambition for water quality. To realize this ambition an integral approach to water treatment involving new technologies as membrane filtration and UV is necessary. The paper will present the possibilities of the current level of technology, how it relates to the vision and ambition of the Dutch drinking water sector and the role of research -- especially in UV technology and membrane filtration -- in realizing long-term goals. [ABSTRACT FROM AUTHOR]

1. Pronounced hypoaldosteronism was found in five young women with low-renin hypertension and characteristic features of the mineralocorticoid hypertensive syndrome. 2. There was no overproduction of the mineralocorticoids 11-deoxycorticosterone and 18-OH-11-deoxycorticosterone. 3. Dexamethasone restored blood pressure to normal, decreased body weight, increased plasma potassium, and increased plasma renin activity and aldosterone excretion in all patients. 4. The data suggest overproduction of an unknown adrenocorticotrophic hormone-dependent mineralocorticoid maintaining hypertension in these patients.

The polymerase chain reaction and hybridization to genomic blots were used to investigate whether the previously observed inclusion of 5S ribosomal RNA genes in the 28S-18S ribosomal DNA intergenic regions of some crustacean species (copepods) could also be detected in other arthropods. Such an arrangement was found not only in other calanoid copepod species but also in a cirriped, an euphausid, and a spider. It is interesting that species from two different calanoid copepod genera do not have this type of arrangement. We conclude that the inclusion of 5S ribosomal RNA genes within the ribosomal DNA repeats has probably occurred repeatedly during the evolution of arthropod species and that the mechanism(s) responsible for these insertions could also be responsible for their loss.

This practical guide based on personal experience explains how simple medical centers, established in remote areas of the world, cannot only provide critically needed services but also be an effective evangelistic tool for the local church as it follows Christ's command to heal the sick.

In the seeds ofAllium altaicun(Pall.)Reysea set of enzymes was found, metabolizing choline esters, composed of active choline esterases and choline acetyltransferase. Choline esterase cleaving acetylcholine occurs in five isoenzymes. The enzyme preparation hydrolyses strongly acetylthiocholine and sinapine, but weakly butyrylthiocholine (20%) in comparison with acetylthiocholine. The hydrolysis of the substrates mentioned is inhibited by physostigmine and neostigmine, but it is not inhibited by the specific inhibitor of acetylcholine esterase (BW 284 C51). In addition to hydrolytic activity a strong catalytic activity of choline acetyltransferase was also observed during the synthesis of sinapine from sinapic acid and choline. The detection of the mentioned enzymes in some representatives of theAlliumgenus indicates that choline esterases are more widely distributed in monocotyledons than previously assumed.