5,298 research outputs found

    Treatment of high strength industrial wastewater with membrane bioreactors for water reuse: Effect of pre-treatment with aerobic granular sludge on system performance and fouling tendency

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    In this study, the treatment of citrus wastewater with membrane bioreactors (MBRs) under different configurations was investigated for water reuse. In particular, one MBR and one aerobic granular sludge MBR (AGS+MBR) bench scale plants were operated for 60 days. The experimental campaign was divided into two periods. In Phase I, a conventional hollow fiber MBR was employed for the treatment of the raw high strength wastewater, whereas in Phase II a combination of in-series reactors (AGS plus MBR) was adopted for the treatment of the high strength citrus wastewater The results demonstrated that both plant configurations enabled very high COD removal, with average values close to 99%. Respirometric batch tests revealed a considerable high metabolic activity of the biomass in both plant configurations, with higher values in the AGS+MBR. It was speculated that the MBR reactor enriched in active biomass deriving from the erosion of the external granule layers in the upstream reactor. In terms of fouling tendency, higher resistance to filtration was observed in the AGS+MBR plant, also characterized by higher irremovable resistance increase compared to the MBR plant that might severely affect the membrane service life

    Study of aerobic granular sludge stability in a continuous-flow membrane bioreactor

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    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

    Tools for quality assurance and assessment of Agricultural Engineering programmes, TUNING subject-area lines and disappearing/rare knowledge in Italy

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    The quality assurance process applied by Italian State University institutions, in order to achieve some level of internal quality control or assessment for the offered study programmes, is established in the funding criteria of the Ordinary Financing Fund (FFO), decided by the National Committee for the Evaluation of the University System (CNVSU). In most Italian Universities the quality assurance and assessment procedure of the study programmes starts with a report, written by a specific committee, that carries out an internal assessment, by which the strong and weak points of the study programme and the related causes are focused. The quality assurance and assessment procedure appoints three autonomous and independent assessors, who have the task of carrying out an external assessment of the degree study programmes and publishing an evaluation report. In Italian Universities the Faculty Assembly holds the tasks of: setting the education and research objectives and evaluating the success in satisfying them; providing, monitoring and enhancing the intellectual and material resources; demonstrating high standards to external assessors and taking into account their reports; co-operating with representatives of professional bodies for carrying out the examination for accessing the professional activity; planning new programme specifications; monitoring student career progression. The Degree Study Programme Assembly holds the task of approving the study programmes of individual students. Moreover, in Italy the Ministry of Education, University and Research, the region administration and the University academic bodies hold the responsibility of: overseeing academic quality and standards; managing the University education and research strategy; overseeing the development and management of quality assurance procedures; approving Faculty recommendations related to the proposal of new study programmes and/or the discontinuation of existing ones. In Italy the Standard Assessment procedure for students is based on the following principles: students can take an examination for a specific course as many times as they wish; examiners and assessors are appointed by the Faculty Dean, while a specific committee is responsible for University examinations; students are finally examined for their thesis by a Faculty committee. Italian Universities offer a Code of Practice for education and research, which is included in several laws and decrees, that set out the guidelines which must be followed in managing a study programme and designing the related courses. In Italy the typical degree profiles in Agricultural/Biosystems Engineering, for the three study levels, are offered by five University Faculties of Agriculture. As regards the status of rare/disappearing knowledge in Agricultural/Biosystems Engineering studies in Italy, it is needed to focus especially on the following subjects: historical farm buildings and new purposes; agritourism; agricultural museums. In Italy several actions try to protect and revitalise the historical farm buildings and, therefore, create jobs and profit for the local community. The destiny of Italian old buildings mainly depends on the implementation of integrated rural development plans, taking into account the landscaping and environmental functions of farms. Converting historical farm buildings or houses into B&B lodges, farm hotels and restaurants generates a new farm activity called agritourism. In Italy, where more than 1600 farm resorts are available, incentives provided for agritourism have been successful in preventing the depopulation of the countryside. A historical farm building can be converted into an agricultural museum. More than 500 agricultural museums are available throughout Italy

    Flood hazard of the Somma-Vesuvius region based on historical (19-20th century) and geomorphological data

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    This paper presents a preliminary susceptibility map of the flood hazard for the Somma-Vesuvius volcanic district, worked out by means of multidisciplinary historical, geological, geomorphological and rainfall data processing. It is well known that the Somma-Vesuvius volcano, due to its explosive volcanism and the dense urbanization of the surrounding area, with a population exceeding 650,000 is one of the most dangerous active volcanoes of the world. Although this area has been extensively studied from the volcanological point of view with regards to its volcanic hazard, there are currently not many detailed studies about its flood hazard factors, despite the fact that, in the last century, many intense rainfall events in this area have produced several floods that invaded the surrounding plains affecting towns and roads, and causing much damages and loss of lives. Accordingly, in this paper high-resolution DEM (5×5 m pixel) and detailed geomorphological maps of the whole area have been analyzed and processed in GIS environment, carrying out a comparative study of the present-day morphology and the morphology of the 1900’s volcanic edifice, including changes of infrastructures and buildings throughout the last century. These results, together with historical chronicles data and the rainfall accurate data for all flood events, have been processed in this paper for highlighting the drainage basins areas of Somma-Vesuvius where the flood phenomena could be more probable in the future, working out a preliminary zoning map, also suggesting in which sectors interventions useful for mitigation of flood risk should be implemented

    In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts.

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    The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR.The amount of proteins characteristic for cardiac cells (alpha-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively) inclines toward an increase in both alpha-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart

    Flood susceptibility assessment in a highly urbanized alluvial fan: the case study of Sala Consilina (southern Italy)

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    Abstract. This paper deals with the risk assessment to alluvial fan flooding at the piedmont zone of carbonate massifs of the southern Apennines chain (southern Italy). These areas are prime spots for urban development and are generally considered to be safer than the valley floors. As a result, villages and towns have been built on alluvial fans which, during intense storms, may be affected by flooding and/or debris flow processes. The study area is located at the foothills of the Maddalena mountains, an elongated NW-SE trending ridge which bounds to the east the wide intermontane basin of Vallo di Diano. The area comprises a wide detrital talus (bajada) made up by coalescent alluvial fans, ranging in age from the Middle Pleistocene to the Holocene. Historical analysis was carried out to ascertain the state of activity of the fans and to identify and map the zones most hit by past flooding. According to the information gathered, the Sala Consilina fans would appear prone to debris flows; in the past these processes have produced extensive damage and loss of life in the urban area. The watershed basins feeding the fans have very low response times and may produce debris flow events with high magnitudes. Taking into account the historical damage, the fan surface morphology, and the present urban development (street orientation and hydraulic network), the piedmont area was zoned and various susceptibility classes were detected. These results may represent a useful tool for studies aiming at territorial hazard mapping and civil protection interventions

    Mechanistic insights into the release of doxorubicin from graphene oxide in cancer cells

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    Liposomal doxorubicin (L-DOX) is a popular drug formulation for the treatment of several cancer types (e.g., recurrent ovarian cancer, metastatic breast cancer, multiple myeloma, etc.), but poor nuclear internalization has hampered its clinical applicability so far. Therefore, novel drug-delivery nanosystems are actively researched in cancer chemotherapy. Here we demonstrate that DOX-loaded graphene oxide (GO), GO-DOX, exhibits much higher anticancer efficacy as compared to its L-DOX counterpart if administered to cellular models of breast cancer. Then, by a combination of live-cell confocal imaging and fluorescence lifetime imaging microscopy (FLIM), we suggest that GO-DOX may realize its superior performances by inducing massive intracellular DOX release (and its subsequent nuclear accumulation) upon binding to the cell plasma membrane. Reported results lay the foundation for future exploitation of these new adducts as high-performance nanochemotherapeutic agents

    Flame pyrolysis synthesis of mixed oxides for glycerol steam reforming

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    Flame spray pyrolysis was used to produce nanosized Ni-based catalysts starting from different mixed oxides. LaNiO3 and CeNiO3 were used as base materials and the formulation was varied by mixing them or incorporating variable amounts of ZrO2 or SrO during the synthesis. The catalysts were tested for the steam reforming of glycerol. One of the key problems for this application is the resistance to deactivation by sintering and coking, which may be increased by (1) improving Ni dispersion through the production of a Ni-La or Ni-Ce mixed oxide precursor, and then reduced; (2) using an oxide as ZrO2, which established a strong interaction with Ni and possesses high thermal resistance; (3) decreasing the surface acidity of ZrO2 through a basic promoter/support, such as La2O3; and (4) adding a promoter/support with very high oxygen mobility such as CeO2. A further key feature is the use of a high temperature synthesis, such as flame spray pyrolysis, to improve the overall thermal resistance of the oxides. These strategies proved effective to obtain active and stable catalysts at least for 20 h on stream with very limited coke formation
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