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561.

Current Research

Fire safety engineering science program  相似文献   
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Xenobiotic compounds accumulate in activated sludge resulting from wastewater treatment plants serving both civil and industrial areas. The opportunity to use anaerobic digestion for the decontamination and beneficial disposal of a contaminated activated sludge was investigated in mesophilic and thermophilic microcosms monitored through an integrated chemical, microbiological and ecotoxicological procedure. The 10 months anaerobic sludge incubation at 35 degrees C resulted in an extensive production of a methane-rich biogas, a marked reduction of pathogenic cultivable bacteria and, importantly, a marked biodegradation of the sludge-carried organic pollutants, including some polychlorinated biphenyls and polycyclic aromatic hydrocarbons, along with a relevant sludge detoxification. The sludge decontamination seemed to occur mostly under methanogenic conditions and was not significantly affected by the addition of yeast extract or molasses. Lower bioremediation and biomethanization yields were observed under thermophilic conditions.  相似文献   
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Mobile Networks and Applications - We describe the design of a Web-based game application aimed to support high-functioning individuals affected by Autism Spectrum Disorder in gaining skills that...  相似文献   
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The in vitro response of primary human osteoblast-like (HOB) cells to a novel hydroxyapatite (HA) coated titanium substrate, produced by a low temperature electrochemical method, was compared to three different titanium surfaces: as-machined, Al2O3-blasted, plasma-sprayed with titanium particles. HOB cells were cultured on different surfaces for 3, 7 and 14 days at 37 °C. The cell morphology was assessed using scanning electron microscopy (SEM). Cell growth and proliferation were assessed by the measurement of total cellular DNA and tritiated thymidine incorporation. Measurement of alkaline phosphatase (ALP) production was used as an indicator of the phenotype of the cultured HOB cells. After three days incubation, the electrochemically coated HA surface produced the highest level of cell proliferation, and the Al2O3-blasted surface the lowest. Interestingly, as the incubation time was increased to 7 days all surfaces produced a large drop in tritiated thymidine incorporation apart from the Al2O3-blasted surface, which showed a small increase. Cells cultured on all four surfaces showed an increased expression of ALP with increased incubation time, although there was not a statistically significant difference between surfaces at each time point. Typical osteoblast morphology was observed for cells cultured on all samples. The HA coated sample showed evidence of a deposited phase after three days of incubation, which was not observed on any other surface. Cells incubated on the HA coated substrate appeared to exhibit the highest number of cell processes attaching to the surface, which was indicative of optimal cell attachment. The crystalline HA coating, produced by a low temperature route, appeared to result in a more bioactive surface on the c.p. Ti substrate than was observed for the other three different Ti surfaces.  相似文献   
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