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• Biological and photocatalysis treatments in-series enabled high TOC removal (ca. 95%). • High photocatalysis performance was achieved because of the MBR pre-treatment. • The addition of K 2 S 2 O 8 reduced the necessity of cumulative impinging energy (60 E). • Membrane fouling mechanisms were the "cake layer deposition" and the "pore blocking". This study investigated the treatment of a shipboard slop containing commercial gasoline in a pilot plant scale consisting of a membrane biological reactor (MBR) and photocatalytic reactor (PCR) acting in series. The MBR contributed for approximately 70% to the overall slop purification. More precisely, the biological process was able to remove approximately 40%, on average, of the organic pollution in the slop. Nevertheless, the membrane was capable to retain a large amount of organic molecules within the system, amounting for a further 30% of the influent total organic content removal. However, this affected the membrane fouling, thus resulting in the increase of the pore blocking mechanism that accounted for approximately 20% to the total resistance to filtration (2.85∙1013 m−1), even if a significant restoration of the original membrane permeability was obtained after chemical cleanings. On the other hand, the biological treatment produced a clear solution for the photocatalytic system, thereby optimizing the light penetration and generation of highly oxidizing active oxygen species that enabled the degradation of bio-recalcitrant compounds. Indeed, low total organic carbon (TOC) values (<10 mg L−1) were achieved in the output of the photocatalytic reactor by means of only 60 Einstein (E) of cumulative impinging energy after the addition of K 2 S 2 O 8. Overall, coupling the two processes enabled very high TOC removal (ca. 95%). [ABSTRACT FROM AUTHOR]

This study investigated the treatment of a shipboard slop containing commercial gasoline in a pilot plant scale consisting of a membrane biological reactor (MBR) and photocatalytic reactor (PCR) acting in series. The MBR contributed for approximately 70% to the overall slop purification. More precisely, the biological process was able to remove approximately 40%, on average, of the organic pollution in the slop. Nevertheless, the membrane was capable to retain a large amount of organic molecules within the system, amounting for a further 30% of the influent total organic content removal. However, this affected the membrane fouling, thus resulting in the increase of the pore blocking mechanism that accounted for approximately 20% to the total resistance to filtration (2.85·1013 m-1), even if a significant restoration of the original membrane permeability was obtained after chemical cleanings. On the other hand, the biological treatment produced a clear solution for the photocatalytic system, thereby optimizing the light penetration and generation of highly oxidizing active oxygen species that enabled the degradation of bio-recalcitrant compounds. Indeed, low total organic carbon (TOC) values (<10m gL-1) were achieved in the output of the photocatalytic reactor by means of only 60 Einstein (E) of cumulative impinging energy after the addition of K2S2O8. Overall, coupling the two processes enabled very high TOC removal (ca. 95%). [ABSTRACT FROM AUTHOR]

A membrane bioreactor (MBR) pilot plant was operated in two subsequent experimental periods (namely, Periods I and II) with different start-up and sludge withdrawal strategies to study its peculiar biokinetic behavior by using respirometric techniques. Two extreme operational conditions were chosen to investigate the different biomass activity under dynamic or pseudostationary conditions during and after the start-up phases. Particularly, the MBR pilot plant was operated with the same volumetric loading rate (VLR) and permeate flux but differently managed during the start-up phase. In Period I, the MBR pilot plant was started up without sludge inoculum and operated without sludge withdrawals; on the contrary, in Period II the MBR pilot plant was started up with sludge inoculum and operated with regular sludge withdrawals. The obtained results highlighted that the different start-up strategies significantly affected the value of the yield coefficient, the storage phenomena, the decay coefficient, and the maximum respiration rates of heterotrophic species. More specifically, both experimental periods underlined interesting aspects related to the bacterial behavior under significant stress conditions occurring during a non-steady-state (start-up) phase. [ABSTRACT FROM AUTHOR]

A granular continuous-flow membrane bioreactor with a novel hydrodynamic configuration was developed to evaluate the stability of aerobic granular sludge (AGS). Under continuous-flow operation (Period I), AGS rapidly lost their structural integrity resulting in loose and fluffy microbial aggregates in which filamentous bacteria were dominant. The intermittent feeding (Period II) allowed obtaining the succession of feast and famine conditions that favored the increase in AGS stability. Although no further breakage occurred, the formation of new granules was very limited, owing to the absence of the hydraulic selection pressure. These results noted the necessity to ensure, on the one hand the succession of feast/famine conditions, and on the other, the hydraulic selection pressure that allows flocculent sludge washout. This preliminary study shows that the proposed configuration could meet the first aspect; in contrast, biomass selection needs to be improved. [ABSTRACT FROM AUTHOR]

Objectives: Since the new millennium, the number of e-health users has significantly increased. Among these, a particular category of people who are interested by this phenomenon is the one of pregnant women. The aim of the present study is to assess the sociodemographic and geographic differences existing in a sample of Italian pregnant women who search for information on the web. Study design: Multicenter cross-sectional survey. Methods: The present study has been conducted from November 2011 to September 2012, in seven Italian cities, located in the North, in the Centre and in the South of Italy. Data were collected through an anonymous questionnaire, administered in waiting rooms of outpatient departments by trained medical doctors. Data were analysed through multivariate logistic regression models. Results: Overall, 1347 responders were interviewed. Eighty-six percent of them declared to surf the internet to retrieve pregnancy-related information. The most searched topics were fetal development (51.3%), healthy lifestyle during pregnancy (48.7%), physiology of pregnancy (39.8%), generic and specific tips/advices during pregnancy (37.2%) and lactation (36.8%). Statistically significant differences (P < 0.05) according to geographic origin, age and educational level were found with regard to the most frequently searched information on the Web, the reasons that pushed pregnant women to practice e-health, and the possibility to change lifestyles after e-health. [ABSTRACT FROM AUTHOR]

The effect of intermittent aeration (IA) on a MBR system was investigated. The study was aimed at analyzing different working conditions and the influence of different IA cycles on the biological performance of the MBR pilot plant, in terms of organic carbon and ammonium removal as well as extracellular polymeric substances (EPSs) production. The membrane modules were placed in a separate compartment, continuously aerated. This configuration allowed to disconnect from the filtration stage the biological phenomena occurring into the IA bioreactor. The observed results highlighted good efficiencies, in terms of organic carbon and ammonium removal. It was noticed a significant soluble microbial products (SMPs) release, likely related to the higher metabolic stress that anoxic conditions exerted on the biomass. However, the proposed configuration, with the membranes in a separate compartment, allowed to reduce the EPSs in the membrane tank even during the non-aerated phase, thus lowering fouling development. [ABSTRACT FROM AUTHOR]