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排序方式: 共有249条查询结果,搜索用时 15 毫秒
161.
Carles Cruz-Morató Laura Ferrando-Climent Sara Rodriguez-Mozaz Damià Barceló Ernest Marco-Urrea Teresa Vicent Montserrat Sarrà 《Water research》2013
The constant detection of pharmaceuticals (PhACs) in the environment demonstrates the inefficiency of conventional wastewater treatment plants to completely remove them from wastewaters. So far, many studies have shown the feasibility of using white rot fungi to remove these contaminants. However, none of them have studied the degradation of several PhACs in real urban wastewater under non-sterile conditions, where mixtures of contaminants presents at low concentrations (ng L−1 to μg L−1) as well as other active microorganisms are present. In this work, a batch fluidized bed bioreactor was used to study, for the first time, the degradation of PhACs present in urban wastewaters at their pre-existent concentrations under non-sterile conditions. Glucose and ammonium tartrate were continuously supplied as carbon and nitrogen source, respectively, and pH was maintained at 4.5. Complete removal of 7 out of the 10 initially detected PhACs was achieved in non-sterile treatment, while only 2 were partially removed and 1 of the PhACs analyzed increased its concentration. In addition, Microtox test showed an important reduction of toxicity in the wastewater after the treatment. 相似文献
162.
163.
ABC14.5 (Rpb8) is a eukaryotic subunit common to all three nuclear RNA polymerases. In Saccharomyces cerevisiae, ABC14.5 (Rpb8) is essential for cell viability, however its function remains unknown. We have cloned and characterised the Schizosaccharomyces pombe rpb8(+) cDNA. We found that S.pombe rpb8, unlike the similarly diverged human orthologue, cannot substitute for S.cerevisiae ABC14. 5 in vivo. To obtain information on the function of this RNA polymerase shared subunit we have used S.pombe rpb8 as a naturally altered molecule in heterologous expression assays in S.cerevisiae. Amino acid residue differences within the 67 N-terminal residues contribute to the functional distinction of the two yeast orthologues in S.cerevisiae. Overexpression of the S.cerevisiae largest subunit of RNA polymerase III C160 (Rpc1) allows S.pombe rpb8 to functionally replace ABC14.5 in S.cerevisiae, suggesting a specific genetic interaction between the S.cerevisiae ABC14.5 (Rpb8) and C160 subunits. We provide further molecular and biochemical evidence showing that the heterologously expressed S.pombe rpb8 molecule selectively affects RNApolymerase III but not RNA polymerase I complex assembly. We also report the identification of a S.cerevisiae ABC14.5-G120D mutant which affects RNA polymerase III. 相似文献
164.
165.
Carles Garrigues Sergi Robles Joan Borrell 《Journal of Network and Computer Applications》2008,31(4):487-508
In this paper we present a novel mechanism for the protection of dynamic itineraries for mobile agent applications. Itineraries that are decided as the agent goes are essential in complex applications based on mobile agents, but no approach has been presented until now to protect them. We have conceived a cryptographic scheme for shielding dynamic itineraries from tampering, impersonation and disclosure. By using trust strategically, our scheme provides a balanced trade-off between flexibility and security. Our protection scheme has been thought always bearing in mind a feasible implementation, and thus facilitates the development of applications that make use of it. An example application based on a real healthcare scenario is also presented to show its operation. 相似文献
166.
The environmental impact of the Spanish national hydrological plan on the lower Ebro river and delta
The main goal of the Spanish National Hydrological Plan is the implementation of an inter-basin water transfer of a maximum of 1050 hm 3 /year from the lower Ebro River to the north and south Mediterranean coast. The plan also includes an additional list of public works of about 100 new dams and the infrastructure for new irrigation areas, as well as water treatment plants and river canalizations, etc. Taking into accout that the planned Ebro transfer would take 50 m 3 /s during 8 months, and that river flow is mostly in the interval of 150-250 m 3 /s during this period, the abstraction would repesent between one-third and one-fifth of the Ebro flow. This plan, if implemented, would have a strong negative environmental impact on the fluvial ecosystem, as well as on the estuarine and marine ecosystems, but these impacts have not been properly considered in the environmental assessment. This paper principally deals with the environmental effects of the water transfer on the area that supplies the water, downstream from the diversion point. The impact of an inter-basin water transfer on the mouth area is based on three aspects: (1) there is an increase in salinity in the delta and estuary; (2) there is a decrease in the biological productivity, mostly due to the decrease of nutrient inputs, and there are also changes in the species distribution; and (3) the river carries less sediment, which affects the geomorphology of the system. The possible effects of lower water quality and changes in the fluvial system have also to be considered. The sustainability of deltas can only be guaranteed with the allocation of an appropriate flow regime, which must include not only a liquid flow, but also a solid flow (sediment), given that deltas and coastal systems need sediment inputs (and nutrients) from the river to maintain their structure and dynamics. The classical methods of determining environmental flows in rivers are neither designed nor adequate for the objective of maintaining the deltas and estuaries in a good ecological state. The determination and implementation of an environmental flow regime not only for the river but also for the coastal and marine systems represent a new challenge for scientists and managers. 相似文献
167.
Carles M. Gasol Xavier Gabarrell Miquel Rigola Sara González-García 《Biomass & bioenergy》2011,35(7):2975-2985
Environmental analysis tools as LCA and GIS have been combined to provide an integrated methodology able to determine suitable areas for cultivating Brassica spp. (B. carinata and B. napus) and Populus spp and for proposing local and decentralised energy production and consumption scenario. The methodology is applied and verified in a Catalonia (southern Europe) case study area but it can be extrapolated to other Mediterranean regions with similar agroclimates.The results obtained show that a high impact reduction in potential global warming category can be achieved annually (annual reduction of 1,954,904 Mg of CO2 eq.) in a local scale scenario.Environmental integration such as GIS and LCA provide a methodology capable of giving enough information and results to determine an energy crop implementation strategy for reducing energy consumption and CO2 eq. emissions. 相似文献
168.
Non-destructive estimation of moisture,water activity and NaCl at ham surface during resting and drying using NIR spectroscopy 总被引:1,自引:0,他引:1
This paper describes the ability of near infra-red reflectance (NIR) spectroscopy to predict moisture, water activity (aw) and NaCl content at the surface of dry-cured ham during the process. A Fourier Transform (FT) NIR spectrometer and two probes (on-contact and remote) were tested directly on the surface (gracilis muscle) of 98 hams during the process. The highest precision was achieved when two spectra per sample were used in the predictive model development. The models based on the remote measurement probe yielded acceptable results with determination coefficients (r2) of 0.93, 0.62 and 0.91 and residual predictive deviation (RPD) of 3.74, 1.63 and 3.33 for moisture, aw and NaCl content, respectively. These results show that NIR measurements could be included in the control system of the resting and drying processes to prevent crusting in dry-cured ham. 相似文献
169.
Eliana Ramírez Roger Bringué Carles Fité Montserrat Iborra Javier Tejero Fidel Cunill 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2017,92(11):2775-2786
The use of acidic ion exchange resins in the transformation of biomass into biofuels is revised and their potential application is presented. Relationships between morphology and structure of resins and their catalytic activity for some existing reactions of the transformation network from sugars to biofuels are observed. In the synthesis of 5‐hydroxymethyfurfural and levulinic acid, catalytic activity of resins increases when the crosslinking content is decreased for both macroreticular and gel‐type resins. Gel‐type resins with low crosslinking were found to be the most suitable resins for direct esterification of levulinic acid with linear alcohols. However, for the alcoholysis of furfuryl alcohol, macroreticular resins are better than gel‐type ones. Deactivation probably due to humins formation is the main drawback for industrial application. © 2017 Society of Chemical Industry 相似文献
170.
Lucía Villamaan Laura Martínez-Escard Carles Arús Victor J. Yuste Ana P. Candiota 《International journal of molecular sciences》2021,22(7)
Background: The relevance of the cancer immune cycle in therapy response implies that successful treatment may trigger the exposure or the release of immunogenic signals. Previous results with the preclinical GL261 glioblastoma (GB) showed that combination treatment of temozolomide (TMZ) + CX-4945 (protein kinase CK2 inhibitor) outperformed single treatments, provided an immune-friendly schedule was followed. Our purpose was to study possible immunogenic signals released in vitro by GB cells. Methods: GL261 GB cells were treated with TMZ and CX-4945 at different concentrations (25 µM–4 mM) and time frames (12–72 h). Cell viability was measured with Trypan Blue and propidium iodide. Calreticulin exposure was assessed with immunofluorescence, and ATP release was measured with bioluminescence. Results: TMZ showed cytostatic rather than cytotoxic effects, while CX-4945 showed remarkable cytotoxic effects already at low concentrations. Calreticulin exposure after 24 h was detected with TMZ treatment, as well as TMZ/CX-4945 low concentration combined treatment. ATP release was significantly higher with CX-4945, especially at high concentrations, as well as with TMZ/CX-4945. Conclusions: combined treatment may produce the simultaneous release of two potent immunogenic signals, which can explain the outperformance over single treatments in vivo. A word of caution may be raised since in vitro conditions are not able to mimic pharmacokinetics observed in vivo fully. 相似文献