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Long-term performance and fouling behavior of four full-scale nanofiltration (NF) plants, treating anoxic groundwater at 80% recovery for drinking water production, were characterized and compared with oxic NF and reverse osmosis systems. Plant operating times varied between 6 and 10 years and pretreatment was limited to 10 µm pore size cartridge filtration and antiscalant dosage (2–2.5 mg L −1 ) only. Membrane performance parameters normalized pressure drop (NPD), normalized specific water permeability ( K w ) and salt retention generally were found stable over extended periods of operation (>6 months). Standard acid–base cleanings (once per year or less) were found to be sufficient to maintain satisfying operation during direct NF of the described iron rich (≤8.4 mg L −1 ) anoxic groundwaters. Extensive autopsies of eight NF membrane elements, which had been in service since the plant startup (6–10 years), were performed to characterize and quantify the material accumulated in the membrane elements. Investigations using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), total organic carbon (TOC) and adenosine triphosphate (ATP) measurements revealed a complex mixture of organic, biological and inorganic materials. The fouling layers that developed during half to one year of operation without chemical cleaning were very thin ( The high solubility of reduced metal ions and the very slow biofilm development under anoxic conditions prevented rapid fouling during direct NF of the studied groundwaters. When compared to oxic NF and RO systems in general (e.g. aerated ground waters or surface waters), the operation and performance of the described anoxic installations (with minimal pretreatment) can be described as very stable.

Extensive description of the four domains of frailty. (DOCX 17Â kb)

Results of the logistic regression analyses on the associated factors with frailty on any of the domains. (DOCX 19Â kb)

Drinking water utilities in Europe are faced with a growing presence of organic micropollutants in their water sources. The aim of this research was to assess the robustness of a drinking water treatment plant equipped with reverse osmosis and subsequent activated carbon filtration for the removal of these pollutants. The total removal efficiency of 47 organic micropollutants was investigated. Results indicated that removal of most organic micropollutants was high for all membranes tested. Some selected micropollutants were less efficiently removed (e.g. the small and polar NDMA and glyphosate, and the more hydrophobic ethylbenzene and napthalene). Very high removal efficiencies for almost all organic micropollutants by the subsequent activated carbon, fed with the permeate stream of the RO element were observed except for the very small and polar NDMA and 1,4-dioxane. RO and subsequent activated carbon filtration are complementary and their combined application results in the removal of a large part of these emerging organic micropollutants. Based on these experiments it can be concluded that the robustness of a proposed treatment scheme for the drinking water treatment plant Engelse Werk is sufficiently guaranteed.

Resume Les enfants atteints de paralysie cerebrale severe ont une capacite de mouvement tres reduite qui ne leur permet pas de se deplacer de facon independante en milieu aquatique. Le Nenuphar est une aide technique aquatique qui assure la flottaison et facilite les mouvements de ces enfants de facon independante sous la surveillance d’une tierce personne. Cet article decrit le Nenuphar ainsi que ses avantages par rapport aux accessoires habituels de flottaison. Des photographies illustrent son utilisation par une enfant atteinte de paralysie cerebrale de forme quadriplegique spastique et un enfant atteint d’amyotrophie spinale infantile. L’objectif du Nenuphar est d’assurer un bon positionnement du tronc, tout en liberant la motricite des membres, pour les enfants atteints d’un handicap moteur severe. En permettant la pratique d’une activite physique aquatique, il favorise le developpement moteur et l’interaction sociale de ces enfants.

A field trial was conducted on Vancouver Island to evaluate the efficacy of the native fungus Neonectria neomacrospora as a biocontrol agent of hemlock dwarf mistletoe (Arceuthobium tsugense), a conifer parasite. Treatments consisted in formulated inoculum of N. neomacrospora applied to unwounded and wounded A. tsugense swellings. After 10 months, the amount of bark necrosis for the wounded, inoculated treatment was significantly greater than for the other treatments. Similarly, sporodochia were more common (present on 50% of swellings) for the wounded, inoculated treatment than the other treatments (present on less than 10% of swellings). Neonectria neomacrospora was isolated from 55.0% of unwounded, inoculated swellings and from 73.7% of those wounded and inoculated, while isolated from 20.0% of unwounded, uninoculated swellings and from 35.0% of those wounded and uninoculated. These results suggest that, although some infection does occur when inoculum is applied to unwounded swellings of hemlock dwarf...