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Among the factors that obstruct the application of anammox-based technology for nitrogen removal from mainstream municipal wastewater is the water's high organic loads. We hypothesized that some anammox species can adapt and grow in mainstream wastewater in which a minimal temperature of 13-15 °C is maintained. Using the AMX368F and AMX820R PCR-primers, anammox bacteria were detected in influent wastewater (COD/N ratio > 13) and in the anaerobic, anoxic, and aerobic chambers of a full-scale municipal wastewater treatment plant, reaching 10 7 copies/g VSS of the16S rRNA gene. Furthermore, anammox activity was demonstrated by 15 N-isotopic tracing. The DNA sequences of clones randomly selected from a clone library were mainly clustered with Candidatus Brocadia flugida in addition to Ca. Brocadia sinica, Ca. Jettenia asiatica, and Ca. Anammoxoglobus propionicus. However, Ca. Brocadia was the only genus detected by high-throughput next-generation sequencing and denaturing gradient gel electrophoresis. The nitrite producers, ammonia-oxidizing archaea and bacteria, were both detected in the influent wastewater and the other chambers, while the nitrite consumers, Nitrospira nitrite oxidizers and the nirS-type denitrifiers, dominated all chambers. The results indicate the occurrence and potential activity of anammox bacteria in mainstream wastewater under certain conditions (proper temperature). The dominance of Brocadia flugida and Anammoxoglobus propionicus suggests a role for volatile fatty acids in selecting the anammox community in wastewater.

This study focuses on the stability and tolerance of continuous-flow bioreactors inoculated with anaerobic methanogens in three different configurations: (R1) dried granular biomass immobilized in PAC-enriched hydrophilic polyurethane foam, (R2) dried granular biomass, and (R3) wet granular biomass. These systems were tested under two different organic loading rates (OLR) of 6.25 and 10.94 (gCOD/(Lreactor∗d)), using a glucose-based synthetic mixture. The effect of an instantaneous shock load of phenol (5g/L for three days), and of phenol inclusion in the feed (0.5g/L) were also tested. At the lower OLR, all reactors performed similarly, however, increasing the OLR lead to a significant biomass washout and failure of R3. Biomass in R1 was more tolerant to phenol shock load than R2, though activity was recovered in both systems after about one month. PAC provided protection and shortened the adaptation time for 0.5g/L phenol that continuously was fed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The main goal of this study was to test the effect of various drying methods of granular anaerobic biomass on biomass survival, potential and rate of methane re-production, and structure. This may facilitate the development of drying methods to preserve excess anaerobic biomass in dry form for re-inoculation of existing digesters after process failure or wash out or for the start-up of new digesters. To that end, anaerobic granular biomass was collected from an up-flow anaerobic sludge blanket (UASB) reactor. The biomass was dried using two alternative methods: oven with air circulation at 50 °C for 24 h (DAO), and vacuum rotary evaporator at anaerobic conditions (DAN). For comparison, the control was a biomass with no drying (WET). Biomass samples were tested for specific methanogenic activity using synthetic wastewater. The microbial communities were also tested for viability using the LIVE/DEAD kit, and total biomass was initially quantified by qPCR targeting 16S rRNA genes. In addition, the mcrA functional gene was used s a target for the detection of the most abundant methanogens. Basic bacterial morphology classification was done by VIT(®) gene probe technology using a fluorescence microscope. Dried DAN and DAO biomasses required approximately four operational runs to recover their initial methanogenic activity compared to WET biomass. LIVE/DEAD results showed clear increases in the proportions of the viable biomass of the total bacterial communities over time, especially for the DAN and DAO samples. A comparison of the qPCR results of both DAN and DAO to the WET biomass showed that the methanogenic mcrA gene fraction of the total biomass population of 16S rRNA gene concentrations decreased moderately by about 17.2% in the samples of DAO and by approximately 6.7% in the samples of DAN over all runs after Run1., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The biotransformation of five selected pharmaceuticals ibuprofen (IBP), ketoprofen (KTP), carbamazepine (CBZ), dexamethasone (DXM) and iopromide (IOP) by a stable nitrifying enrichment culture was investigated at concentrations ranging between 25 μg/L and 2mg/L. Complete biotransformation was observed only for IBP and KTP, although, an inverse correlation between transformation rate and concentration was found. The transformation pattern observed is consistent with ammonia monooxygenase (AMO) activity. The metabolic succession of the compounds according to the biotransformation rates was: IBP>KTP>DXM>CBZ>IOP. A linear correlation between the calculated diffusive flux of the model compounds across a bilayer membrane and their biotransformation rates was found. Our results support the concept that augmentation with nitrifying activity can enhance the removal of trace organic pollutants during effluent treatment. Furthermore, ammonia-oxidizing activity appears as a good indicator for estimation of potential of biodegradability of pharmaceuticals, especially at low concentrations., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The photocatalytic degradation of two phenolic compounds, p-coumaric acid and caffeic acid, was performed with a suspended mixture of TiO(2) and powdered activated carbon (PAC) (at pH=3.4 and 8). Adsorption, direct photolysis and photocatalytic degradation were studied under different pH and UV light sources (sunlight vs. 365nm UV lamps). The potential for reusing this catalyst mixture in sequential photocatalytic runs was examined as well. Quantum yields for the direct photolysis of caffeic acid under solar and artificial 365nm light were calculated (for the first time) as 0.005 and 0.011, respectively. A higher removal rate of contaminants by either adsorption or photocatalysis was obtained at a low pH (pH 4). Furthermore, the addition of PAC increased the removal efficiency of the phenolic compounds. Fast removal of the pollutants from the solution over three sequential runs was achieved only when both TiO(2) and PAC were present. This suggests that at medium phenolic concentrations, the presence of PAC as a co-sorbent reduces surface poisoning of the TiO(2) catalyst and hence improves photocatalysis degradation of phenolic pollutants. The adsorption equilibrium of caffeic acid or p-coumaric acid on TiO(2), PAC and the combined mixture of TiO(2) and PAC follows the Langmuir isotherm model. Experiments with PAC TiO(2) mixture and olive mill wastewater (anaerobically treated and diluted by a factor of 10) showed higher removal of polyphenols than of chemical oxygen demand (COD). 87% removal of total polyphenols, compared to 58% of COD, was achieved after 24h of exposure to 365nm irradiation (7.6W/m(2)) in the presence of a suspended mixture of TiO(2) and PAC, indicating "self-selectivity" of polyphenols., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The main objective of this research is to model the effect of biodegradation process of phenol at high initial concentrations using a well known immobilization technique of the biomass. This work focused on testing the effect of activated carbon and clay while considering the diffusive internal mass transfer limitations. Biodegradation of phenol was performed by using enriched microorganisms from a compost of agricultural wastes. The average phenol biodegradation rate (uptake) of free biomass system was 235.3 mg g(-1) h(-1) at initial concentration range of 212-260 mg/L. However, the values for the systems of immobilized biomass in alginate and activated carbon (1 mm), alginate, activated carbon (4 mm), alginate, activated carbon and clay (1 mm) and alginate, activated carbon and clay (4 mm) were 64.9, 27.6, 27.5, and 8 mg g(-1) h(-1) respectively. The effective diffusion factors in different matrix were obtained using an intra-particle diffusion-based mathematical model. Diffusion limitation was observed when the matrix contained clay in addition to activated carbon. The diffusion coefficient was decreased from 1.6 × 10(-8) to 1.2 × 10(-9) cm(2)/s when clay was added to the matrix of 1 mm of alginate and activated carbon. Also, slight differences between the diffusion factors were observed for larger beads. The combination of clay and AC contributes to better mineralization of phenol at high concentrations. This could be attributed to the synergism of both additives., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Objective: To assess self-reported morbidity and its determining factors in South Lebanon, with an emphasis on the influence of the habitat location (urban vs. rural) and gender., Methods: Cross-sectional survey in 2000 among 524 South Lebanon residents >/=14 years sampled from a random sample of households using a multi-level cluster sampling technique. Data on self-reported morbidity, lifestyle and socioeconomic status were collected through interviews, using a standardized questionnaire. To evaluate deprivation, a new index was created; the modified 'Living Conditions Index'. Stepwise logistic regression analysis was performed to test the effect of habitat and gender on self-reported morbidity., Results: People in one-fifth of the households lived in precarious conditions. Illiteracy was significantly higher in rural than urban settings. Urban residents reported obesity, varicose veins, anxiety/depression and visual disorders more often. Illiteracy, headaches, lumbar pain, varicose veins and anxiety/depression were more frequently reported by women, whereas ulcers, hearing disorders, cardio-vascular diseases and their risk factors were more frequently reported by men. Precarious living conditions were associated with headaches, lumbar pains and insomnia. Individuals covered by a health insurance sought care more often than the uninsured., Conclusion: Habitat location had only a minor influence on self-reported morbidity; women perceived their health as poorer than men and a number of disease conditions were influenced by deprivation. Our study confirms that the epidemiological transition phenomenon had occurred in South Lebanon in 2000. Our community-based data can serve as a baseline for monitoring changes in health in South Lebanon in the future and especially those because of the war that emerged in July 2006.

A new method for studying sorption with diesel and hexane sootwas developed, tested, and applied. A commercial silica-based chromatography medium was used as an inert inorganic carrier for immobilization (entrapment) of soot particles and their aggregates, thus creating a combined sorbent for sorption of hydrophobic organic chemicals (HOCs). After precombustion to remove potential organic carbon contaminants, the silica particles and soot samples were mixed under dry conditions that allowed the soot to be incorporated within the pore structure of the much larger (> 180 microm) carrier particles. Unincorporated soot was removed by multiple rinses with Milli-Q water. Sorption rate and equilibrium experiments were conducted, using phenanthrene as a probe HOC. Strong nonlinear sorption of phenanthrene was observed, in agreement with results previously obtained using air-bridge and flocculation-based methods. Batch kinetic studies suggested that 60 d of prewetting is required to obtain full water saturation, as perhaps needed for proper assessment of phenanthrene uptake rate by soot in aqueous systems. Forthe determination of equilibrium phenanthrene sorption, however, 1-d prewetting is sufficient so long as final equilibration is for at least 60 d. The new method is a practical approach to sorption measurement that may prove especially useful for study of strongly sorbing chemicals.

The transport of polycyclic aromatic hydrocarbons (PAH) in porous media in the presence of dissolved organic matter (DOM) was predicted with a transport bicontinuum model using independently obtained relationships to derive transport parameters for describing the effect of PAH binding to the DOM. The sorption constants of PAHs to soil and their binding constants to DOM were derived from basic correlations with K(ow) (indicator of hydrophobicity). The kinetic (rate) constants were derived from previously published correlations with K(p) (sorption constant). The independently obtained sorption and rate constants were corrected for binding to DOM and were used to predict the breakthrough curves (BTC) of contaminants in the presence and the absence of DOM. Column results confirmed the independently predicted BTC of PAHs in the presence of DOM that did not sorb to the solid phase, as well as the effect of DOM on the rate of the sorption and desorption processes. These findings confirm the ability to quantitatively describe how DOM facilitates transport of contaminants in the subsurface using independently derived parameters.

An experimentally practical and precise flocculation-based method was developed, tested, and applied to determine phenanthrene and 1,2,4-trichlorobenzene sorption with NIST SRM 2975 diesel particulate matter. Following an initial equilibration period, polyaluminum chloride (PACI) solution was added to the sorption tubes in order to facilitate the formation of flocculated aggregates of soot particles. After separation of the solids through centrifugation, supernatant concentrations were determined as with conventional batch methods. The flocculation-based method was tested on three kinds of soot and then used to evaluate sorption kinetics and equilibrium with SRM 2975. Kinetic results showed that wetting of the soot required more than 20 days, but that 60 days was sufficient to achieve equilibration with both water and phenanthrene. Sixty-day isotherms for both phenanthrene and 1,2,4-trichlorobenzene were strongly nonlinear. At approximate 10(-3) of solubility, carbon-normalized distribution coefficients (Koc) were 10-20 times higher than those for absorption to sediment organic matter. Measurements at closer to solubility indicated much lower Koc, suggesting a total sorption capacity at aqueous solubility that is of similar magnitude to that in sediment organic matter. Independent analysis of extractable hydrocarbons suggests that absorption into a native hydrocarbon phase was not a major component of sorption.

Background: Measuring health status in a population is important for the evaluation of interventions and the prediction of health and social care needs. Quality of life (QoL) studies are an essential complement to medical evaluation but most of the tools available in this area are in English. In order to evaluated QoL in rural and urban areas in Lebanon, the short form 36 health survey (SF-36) was adapted into Arabic., Methods: SF-36 was administered in a cross-sectional study, to collect sociodemographic and environmental variables as well as self reported morbidity. We analysed a representative sample containing 1632 subjects, from whom we randomly picked 524 subjects aged 14 years and over. The translation, cultural adaptation and validation of the SF-36 followed the International Quality of Life Assessment methodology. Multivariate analysis (generalized linear model) was performed to test the effect of habitat (rural on urban areas) on all domains of the SF-36., Results: The rate of missing data is very low (0.23% of items). Item level validation supported the assumptions underlying Likert scoring. SF-36 scale scores showed wide variability and acceptable internal consistency (Cronbach's alpha >0.70), factor analysis yielded patterns of factor correlation comparable to that found in the U.S.A and France. Patients resident in rural areas had higher vitality scores than those in urban areas. Older people reported more satisfaction with some domains of life than younger people, except for physical functioning. The QoL of women is poorer than men; certain symptoms and morbidity independently influence the domains of SF-36 in this population., Conclusion: The results support the validity of the SF-36 Arabic version. Habitat has a minor influence on QoL, women had a poor QoL, and health problems had differential impact on QoL.