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Hydrolysis of the lignocellulosic biomass results in the release of high-value chemicals that during industrial processing can be recovered with membrane technologies. To maintain an effective performance of the membranes used in the technological processing of biomass, their regular cleaning is essential. Although several guidelines may be found for membrane cleaning in the cases of organic fouling, the data for cleaning membranes fouled by hydrolyzed lignocellulosic biomass is limited. Current research is aimed to evaluate physical (air backpulse) and common cheap chemical membrane cleaning methods. The results showed that air backpulse alone had a minor (9%) effect on the membrane cleaning. The alternation of NaOH (1 %) solution with the NaClO (200 mg/L of Free chlorine) was the most effective approach for membrane cleaning. The cleaning effectiveness was 95.1 % for 50 nm membrane and 89 % for 200 nm membrane, indicating that membranes used for hydrolyzed lignocellulosic biomass filtration can be effectively cleaned using affordable and accessible chemicals.

Phosphorus (P) is among the most important nutrients required for bacterial growth. It has a great influence on microbial activity even at very small concentrations. Existing chemical methods are not able to determine P at low enough concentrations and to quantify biologically available phosphorus fractions. Therefore, a method of microbially available phosphorus (MAP) determination is used to quantify the amount of P at concentrations below 20 µg/l. Additionally, this method determines the amount of P that can be directly used by microorganisms. Originally it was determined by inoculating sample by Pseudomonas fluorescens (now Ps. brenneri) P17 strain and spread-plated on R2A agar for enumeration. Further, a more rapid method was developed by replacing heterotrophic plate count (HPC) by flow cytometry (FCM). In this paper the use of FCM for MAP determination is validated and compared with HPC method. The results of calibration are presented. The original pure P17 strain was used as inoculum and standards with different PO4-P concentrations were inoculated at 30°C. The gained yield factor by FCM was 1.59x108. FCM results showed strong correlation (R2=0.99) with HPC results, as pure culture was used. Therefore, flow cytometry is a rapid alternative to heterotrophic plate count method for microbially available phosphorus determination.

By using industrial aluminium recycling waste, recycled silicate glass from outworn fluorescence lamp recycling plant, calcined kaolinite clay supplemented with alkali activator with different silicate modulus the new type of porous material for biotechnologic processes without the need for additional equipment for pH control was researched. This controlled-release system contains an alkali activated matrix in which NaOH crystals are encased. In this study ability to release NaOH per time in water according to material composition and structure were investigated. Three alkaline activated materials AAM 7.5, 10 and 12.5, with different alkali activator content were characterized.

The effect of pipe fittings (mainly T-pieces) on particle accumulation in drinking water distribution networks were shown in this work. The online measurements of flow and turbidity for cast iron, polyethylene and polyvinyl chloride pipe sections were linked with analysis of pipe geometry. Up to 0.29 kg of the total amount mobilized in T-pieces ranging from DN 100/100–DN 250/250. The accumulated amount of particles in fittings was defined as J and introduced into the existing turbidity model PODDS (prediction of discoloration in distribution systems) proposed by Boxall et al. (2001) which describes the erosion of particles leading to discoloration events in drinking water network viz sections of straight pipes. However, this work does not interpret mobilization of particles in pipe fittings which have been considered in this article. T-pieces were the object of this study and depending of the diameter or daily flow velocity, the coefficient J varied from 1.16 to 8.02. The study showed that pipe fittings act as catchment areas for particle accumulation in drinking water networks.

The addition of labile organic carbon (LOC) to enhance the biodegradation rate of dissolved organic carbon (DOC) in biological columns was studied. Acetate standard solution (NaAc) and Luria Bertrani (LB) medium were used as LOC as biostimulants in glass column system used for measurements of biodegradable dissolved organic carbon (BDOC). The addition of LOC related with the increase of total DOC in sample. The concentration of BDOC increased up to 7 and 5 times and was utilized after 24 min. contact time. The biodegradation rate constant was increased at least 26 times during adaptation-biostimulation period. There was a strong positive correlation between the biodegradation rate constant and the concentration of BDOC. Biostimulation period ranged from 24 to 53 h for NaAc biostimulant and from 20 to 168 h for LB. The study has shown that LOC could be used as stimulator to enhance the biodegradation rate of DOC during biofiltration.

The effect of phosphorus addition on survival of Escherichia coli in an experimental drinking water distribution system was investigated. Higher phosphorus concentrations prolonged the survival of culturable E. coli in water and biofilms. Although phosphorus addition did not affect viable but not culturable (VBNC) E. coli in biofilms, these structures could act as a reservoir of VBNC forms of E. coli in drinking water distribution systems.

Effect of microbially available phosphorus (MAP) on biofilm development in drinking water systems was investigated at the pilot-scale experiments over 3 years. Completely mixed biofilm reactors Propella® (water detention time 24 h, flow rate 0.25 m s−1, PVC pipe coupons) were used as water distribution network models. Four experimental runs were carried out with water containing different levels of phosphorus which was limiting nutrient for bacterial growth. Positive correlation between MAP in the inlet water and heterotrophic plate count (correlation coefficient 0.95) in biofilm, as well as for the total bacteria number (correlation coefficient 0.71), was observed. However, our experiments showed that removal of phosphorus down to very low levels (below detection limits of chemical method and MAP

Chemical precipitation in combination with biological treatment is a commonly used method for removal of turbidity and dissolved organic carbon (DOC) from drinking water. DOC is largely removed during biological treatment, which includes ozonation and filtration through a biologically active carbon (BAC) filter. Ozone converts humic substances into a biologically labile form that is mineralised by bacteria living in the following BAC filter. This study shows that this approach is often not efficient for removal of DOC from waters with a high amount of humic substances. During chemical treatment, the microbiologically available phosphorus is very efficiently removed, which results in shortages of phosphorus needed for bacteria to mineralise carbon in BAC filters. To enhance removal of DOC by biological treatment, addition of phosphorus prior to the BAC filters should be considered.

Membranes are widely used for the treatment of various solutions. However, membrane fouling remains the limiting factor for their usage, setting biofouling as the most severe type of it. Therefore, the production of biologically stable water prior to membranes is important. Since lack of phosphorus may hinder the growth of microorganisms, the aim of this research is to evaluate the effect of microbially available phosphorus (MAP) removal via affordable water pre-treatment methods (adsorption, biofiltration, electrocoagulation) on bacterial growth. Four cylindrical reactors were installed at an artificially recharged groundwater station. Further temperature influence and carbon limitation were tested for biofiltration technology. The amount of MAP and total cell count was measured by flow cytometry. The results showed that at lower temperatures electrocoagulation performed the best, resulting in complete MAP removal (detection limit 6.27x10-3μg P l-1). Sorbent demonstrated MAP removal of 70-90%. Biomass did not have any noteworthy results at +8°C, however, at +19°C MAP removal of around 80% was achieved. Main conclusions obtained within this study are: (i) tested technologies effectively eliminate MAP levels; (ii) temperature has a significant effect on MAP removal in a bioreactor, (iii) multi-barrier approach might be necessary for better P limitation that might prolong operating time of a membrane.

The present study was designed to describe the turbidity curve obtained during planned unidirectional flushing in drinking water distribution system of a diameter 100-300 mm. The online measurements of flow and turbidity for cast iron (n=16), polyethylene (PE, n=7) and polyvinylchloride (PVC, n=4) pipe sections and calculations of hydraulic values indicated that the turbidity curve peaks appeared at the locations of bends, tees, narrow parts of the pipes etc viz. where increased hydraulic drops take place. The application of on-line measurements during the wash-out of loose deposits in both cases from one and two hydrants simultaneously, the calculations of average velocity (0.72 m/s, n=22) and shear stress (2.05 N/ m 2 , n=29) on pipe walls showed that the loose deposits in the pipes move according to plug-flow principle in a turbulent regime. The granulometric analysis of loose deposits showed that the average diameter ranged from

In the present study the time of adaptation of fixed biomass for biodegradation of natural organic matter was investigated. The experiments were done in columns that are usually used for rapid determination of biodegradable dissolved organic carbon (BDOC). The biomass was adapted to samples with different concentrations of organic substances before measurements by pumping water to be investigated through the columns for several days. The time of adaptation was dependent on the initial concentration of the organic matter in the water sample. The adaptation time increased from 6 to 24 h with increase of concentration of acetate solution from 2 to 10 mg/l, thus adaptation rate decreased simultaneously from 0.28 to 0.11 min(-1). In natural water samples with the initial concentration in the range from 4.61-10.82 mg/l of dissolved organic carbon (DOC) the maximal adaptation time was less than 24 h. During the adaptation period the increase in reproducibility and decrease in the standard deviation was observed. The study showed that adaptation of column to the different concentration of organic matter in water sample is necessary in order to decrease the bias in BDOC measurements when using columns tests.

Fecal fat, bile acid, and neutral sterol excretion and biliary bile acid, phospholipid, and cholesterol were studied in 36 patients 6 to 12 months after jejunoileostomy for obesity. No relationship was observed between the degree of steatorrhea and weight loss, although fecal fat rose sharply in all except 2 patients. Mean neutral sterol excretion in feces was unchanged after operation except in cholecystectomized patients. No relationship could be demonstrated between serum cholesterol decrease and fecal biel acid, which rose 3-fold, or between cholesterol and the sum of fecal fat and neutral sterol. Fecal excretion of cholic and deoxycholic acid together increased more than the total excretion of cxcretion patterns were demonstrable: moderate fecal fat (24 g or less on 65-g intake) was associated with a predominance of secondary bile acids in feces and in bile; high fecal fat (above 24 g/day) was associated with predominantly primary bile acids. A high incidence of gallstones or previous cholecystectomy (36%) was found preoperatively and of 25 patients with normal cholecystograms, four developed stones and five had nonvisualization of gallbladder 6 to 12 months postoperatively. Bile saturation ratio and lithogenic index were not consistently changed postoperatively. No clear cut increase in lithogenic potential or in bile acid (lithocholic acid) hepatotoxic potential after jejunoileostomy was demonstrable.

PLZT and PSN ceramics have been exposed to γ-radiation (energy ≈ 1.15 MeV, dose up to 3 · 109 rad), electron flux (≈4.5 MeV, dose up to 3.1018 electr./cm2) and fast neutrons (≥ 0.1 MeV, dose up to 1018 n/cm2). The irradiated material was used to study radiation effects on dielectric parameters (e and tgδ were measured at frequencies from 1 kHz to 5 MHz), polarization (dielectric hysteresis quasistatic loops) and non-linear optical properties (I2w). The measurements were made in the region of phase transition as well as to examine annealing of radiation-induced defects. As compared to PLZT the PSN ceramics is more resistant to radiation, the most sensitive PLZT compounds being with 7 ≤ × ≤ 9.5 at .% of La. Obtained results are explained by the change of ion charge, redistribution of vacancies in A and B sublattices of PLZT and by possible ion ordering in sublattice B of PSN with account for intrinsic fields in the relevant compounds.

Mean and peak jejunal bile salt concentrations during digestion of a standard fat meal were found to be significantly lower in six Puerto Rican patients with untreated tropical sprue, all of whom had steatorrhoea, than in six asymptomatic subjects who had normal fat absorption. Bile salt pool size and turnover time did not differ significantly in the two groups. It is suggested that bile salt concentrations may be reduced in the proximal small intestine of patients with tropical sprue as a result of excessive dilution by intestinal fluid. The finding of low bile salt concentrations in two asymptomatic subjects indicates that bile salt lack alone may not be sufficient to produce steatorrhoea.

ASPIRIN consumption is associated with gastric mucosal erosions1,2 and upper gastrointestinal haemorrhage3–5, and has been postulated as a factor in the development of chronic peptic ulcer6,7. It has been reported to cause chronic gastric ulcer in rats8. There is, however, no real understanding of the mechanism of these injuries. Menguy et al.9 suggested that the damage to the gastric mucosa results from lack of energy (ATP) for cell function. The reported antagonism of cholera enterotoxin by aspirin in the rat intestine10 might have been mediated through the inhibition of adenyl cyclase. We have now found, however, that aspirin can stimulate the activity of this enzyme in rat gastric mucosa.

Aspirin stimulated gastric mucosal adenyl cyclase activity in rats after oral administration. The stimulation became apparent within 5 min after an oral dose (300 mg/kg body wt). Aspirin was also shown to stimulate adenyl cyclase activity when added to gastric mucosal homogenate in vitro and some correlation was seen between the concentration of aspirin used and adenyl cyclase activity.

Squamous cell cancer was induced in the uterine cervix of S-3H strain of mice within 8 to 12 weeks after implantation. The experiments compared the metabolism of carbohydrates and nucleic acids in the cervical cancer with normal cervical tissue. It determined the effect of cancer growth upon the carbohydrate and nucleic acid metabolism of other essential organs by measuring the following enzymes and metabolites. Lactic acid content, glycogen, glycogen synthetase, glucose-6-phosphate dehydrogenase, and TPN-dependent isocitric dehydrogenase. These substances were significantly altered in the spleen, kidney, and cervical cancer of the cancer animals. The relative rate of mitosis in all structures was evaluated by assaying the tritiated thymidine at various time intervals after intraperitoneal injection. The DNA and RNA content was estimated in all by the quantitative extraction of the nucleic acid fraction. Marked changes in the metabolic rate and nucleic acid metabolism was noted in the spleen, kidney, lymph nodes, and cervical cancer.