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861.
Many universities around the world have served as active centers for research on climate change. However, there are several barriers to their activities, stemming from the nature of research, resources, and the structure of institutions. This document provides an overview of barriers, potential factors, and activities to develop and implement sustainable energy processes in public higher education institutions (HEIs) in Brazil. The research was conducted from March to April of 2018 with representatives of HEIs (rectors or prorectors of research). A total of 63 invitations to respond to the Survey‐monkey survey were emailed, and responses were received from 32 universities. The research concludes by proposing measures that can be taken to make the issue of climate change more present and effective in university research and teaching activities. This includes changes in research, information dissemination, and teaching approaches to better support actions to address climate change. In Brazil, there are many potentialities in terms of natural resources, but actions for implementation are still incipient. Further efforts and investment in research and development will be required.  相似文献   
862.
A screening using several fungi (Phanerochaete chrysosporium, Pleurotus ostreatus, Trametes versicolor and Aureobasidium pullulans) was performed on the degradation of syringol derivatives of azo dyes possessing either carboxylic or sulphonic groups, under optimized conditions previously established by us. T. versicolor showed the best biodegradation performance and its potential was confirmed by the degradation of differently substituted fungal bioaccessible dyes. Enzymatic assays (lignin peroxidase, manganese peroxidase, laccase, proteases and glyoxal oxidase) and GC-MS analysis were performed upon the assay obtained using the most degraded dye. The identification of hydroxylated metabolites allowed us to propose a possible metabolic pathway. Biodegradation assays using mixtures of these bioaccessible dyes were performed to evaluate the possibility of a fungal wastewater treatment for textile industries.  相似文献   
863.
The State of Minas Gerais represents one of Brazil's most outstanding mining resources. The contamination of river waterfrom kaolin processing activities may be harmful to people inthe way of slow but chronic poisoning. On the other hand, the discharge of untreated or inadequately treated domestic sewage into aquatic environments can also cause deleterious effects to the health. However, no reliable figures are available for pollutant occurrences in river water. This draws attention to thevery precarious situation that exists with respect to pollutionby organic and inorganic toxic wastes, especially with respect to humans and fauna in all its expressions. Thus, with the purpose of establishing a preliminary report to trace out industrialisation outcomes, samples of river water, vegetation and fish were collected and analysed to detect pollutant inputs.The concentration of metals was determined in suspended particle,vegetation and fish, while those of nitrite, nitrate, phosphateand chloride were determined in river water samples. The concentration of dissolved oxygen (DO) was measured in river water at the time of collection. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were also determined. Metalinputs in the samples analysed appeared to be related to effluentdischarges into the rivers. The suspended particles showed highconcentrations (in mg kg-1) of zinc (62 600) and aluminium(559 000), while vegetation samples collected near rivers wereheavily contaminated with iron (7680). The fishes examined werecontaminated with chromium (1.5 mg kg-1). In general, the concentrations of nitrite, nitrate, chloride, phosphate and BOD in river water were lower than the maximum values established bythe Brazilian Environmental Standards.  相似文献   
864.
Heavy Metal Availability in Soil Amended with Composted Urban Solid Wastes   总被引:1,自引:0,他引:1  
A study was performed to evaluate the pH and the availability of Zn, Cu, Mn, Pb, and Ni in soil amended with increasing doses of composted solid wastes, collected in Rio de Janeiro, Rio de Janeiro State and in Coimbra, Minas Gerais State, Brazil. The influence of the time elapsed between compost application to the soil and the sampling of the plant growth substrate (soil + compost) for pH and metal availability analyses was also examined. The availability of heavy metals in the soil, in the compost and in the substrate was evaluated using DTPA solution for metal extraction. The increase of the compost doses added to the soil resulted in the increase of the pH in the substrate. The addition of the compost from the bigger city, Rio de Janeiro, resulted in higher increase in soil pH and available Zn, Cu, Pb, and Ni levels as compared to the addition of the compost from the smaller city, Coimbra. Increasing the time elapsed between the compost application to the soil and the sampling of the mixture resulted in higher available Zn, Cu, Mn, and Pb levels. The addition of the compost from Rio de Janeiro resulted in substrate metal concentrations in the order Zn > Pb > Ni > Cu > Mn and for the Coimbra compost the metal concentrations in the substrate was Zn > Pb > Cu > Ni > Mn. The higher values of pH and available metals obtained for the bigger city were attributed to the greatest metal contamination of its compost.  相似文献   
865.
Daily 24 hour composite influent wastewater samples were collected from the wastewater treatment plant of Brussels-North (Belgium) for eight months to study variations in the concentrations and mass loads of nine illicit drugs and metabolites: cocaine (COC) and its metabolites benzoylecgonine (BE) and ecgonine methyl ester (EME), amphetamine (AMP), methylenedioxymethamphetamine (MDMA), methamphetamine (METH), methadone (MTD) and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and the specific metabolite of heroin, 6-monoacetylmorphine (6-MAM). Samples were analyzed using a validated analytical method based on solid-phase extraction and hydrophilic interaction liquid chromatography coupled to tandem mass spectrometry. The selected compounds could be detected and quantified in all samples. The measured concentrations were in agreement with earlier published concentrations, when available. All illicit drugs showed significant differences in mass loads between months. Daily variations were observed for MDMA, AMP and COC and metabolites, with higher mass loads observed during the weekend. This is probably related to their recreational consumption pattern and was further confirmed when holiday periods (New Year's Eve, Belgian national holiday) were in detail investigated. For METH, 6-MAM, MTD and EDDP, stable and consistent amounts were observed during the week. In all samples, the ratio of the concentration of the parent compound to its metabolite(s) was calculated to evaluate whether measured concentrations reflect human excretion of the illicit drugs. For MTD, the ratio of parent compound/metabolite was in agreement with the excretion pattern, while for COC some deviations were observed, resulting from excretion pattern uncertainties, and stability and discharge issues.  相似文献   
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869.
The consumption and production of food products in the municipality of Lisbon in the 1890–1900 decade is assessed with the support of historical cartography and statistical resources. For the first time, food production in a municipality in the turn to the twentieth century is accounted and simultaneously subject of a visual analysis of the land used for agriculture and of the water infrastructures that supported such uses. Agriculture occupied at least 40 % of the territory of the city, while the built environment occupied no more than 16 % of the territory. However, local production of food was far from supplying most of the citizens’ needs, and substantial food imports were needed. In this context, the municipality behaved like a heterotrophic system, highly dependent on the external supply of resources. Moreover, comparing to other European cities at the time Lisbon was facing in the end of the nineteenth century a late and slow transition from an agrarian social metabolism to an industrial one, suggesting that Lisbon was still relatively high-solar-powered as compared to other European cities at the time that were already highly fossil-fuel-powered.  相似文献   
870.
This study tested for fluctuations on short-term consistency (within about 1 month) in the isotopic niche of a pelagic seabird species. Short-term consistency in the isotopic niche was assessed using a wide-ranging apex predator, the Cory’s shearwaters Calonectris diomedea, along a 3-year study (2010–2012), during both the pre-laying and chick-rearing periods, with markedly inter- and intra-annual differences in the foraging spatial distribution at sea and isotopic niche width. We used individual movement data and stable isotope data, analysed using recent metrics based in a Bayesian framework, of 69 adults breeding on a small neritic island in the North Atlantic (39°24′N, 009°30′W). As expected, our results confirm that isotopic niche expansion could arise via increased variation in spatial distribution at sea among individuals. Results suggest fluctuations on short-term consistency in the isotopic niche of Cory’s shearwaters related to their different foraging patterns among periods and, ultimately, to presumably temporal changes in the availability and predictability of food resources. Short-term consistency in the isotopic niche was higher and persistent during periods when the population showed an intermediate isotopic niche width and absent when isotopic niche was either smaller or larger during the study period. These results suggest that consistency in the isotopic niche is an important characteristic of this population during the breeding period that may fluctuate depending on resources availability and should be important to understand the dynamics of foraging ecology of pelagic seabirds in general.  相似文献   
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