94 research outputs found

    Biocover performance of landfill methane oxidation: Experimental results

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    Abstract: An experimental passive methane oxidation biocover (PMOB) was constructed within the existing final cover of the St-Nicéphore landfill. Its substrate consisted of a 0.80-m-thick mixture of sand and compost. The goal of this experiment was to evaluate the performance of the PMOB in reducing CH 4 CH4 emissions when submitted to an increasing methane load. The CH 4 CH4 load applied started with 9.3 g CH 4  m −2  d −1 9.3 g CH4 m−2 d−1 . When the site had to be closed for the winter, the CH 4 CH4 input was 820 g CH 4  m −2  d −1 820 g CH4 m−2 d−1 . Throughout the study, practically all the CH 4 CH4 input was oxidized; absolute removal rates were linearly correlated to methane loading; and the oxidation zone was established between 0.6–0.8 m. These results seem to indicate that the upper limit potential of this PMOB to oxidize CH 4 CH4 was not necessarily reached during the study period. Surface CH 4 CH4 concentration scans showed no signs of leaks. The substrate offered excellent conditions for the growth of methanotrophs, whose count averaged 3.91×10 8  CFU g dw −1 3.91×108 CFU g dw−1 soil

    Causal model to describe the variation of faecal coliform concentrations in a pilot-scale test consisting of ponds aligned in series

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    Abstract: In this study, the application of path analysis was tested to validate a causal model developed to verify the influence on several factors of the variation of faecal coliform concentration in pilot-scale ponds that treat domestic wastewater under distinct physical and operational characteristics. The ponds, aligned in series, are located in the city of Campina Grande, Northeastern Brazil. The model proved to be efficient for describing the variation in both secondary facultative and maturation ponds. The coefficient of determination (R2) varied between 0.66 and 0.84 for the facultative ponds and between 0.54 and 0.95 for the maturation ponds. Effluent faecal coliform concentration was negatively affected by solar radiation in shallow ponds and positively affected by influent faecal coliform concentration in deep ponds. Typically the effects related to phytoplankton photosynthetic activity were well characterized in all shallow maturation ponds. Faecal coliform concentration was negatively affected by pH in almost all the cases. This model is not suitable for anaerobic ponds.La méthodologie du Path analysis a été employé afin de tester un modèle causal qui a été développé pour vérifier l’influence de plusieurs facteurs sur la variation de la concentration en coliformes fécaux dans des étangs de traitement des eaux usées pilotes. Ces dernières sont opérées selon des caractéristiques physiques et fonctionnelles distinctes. Les étangs, alignés en série, se trouvent dans la ville de Campina Grande, dans le Nordeste brésilien. Le modèle s’est révélé efficace pour décrire la variation de la concentration de coliformes fécaux dans les étangs secondaires facultatifs, de même que dans les étangs de maturation. Le coefficient de détermination (R2) a varié de 0,66 à 0,84 dans étangs facultatifs et de 0,54 à 0,95 dans les étangs de maturation. La concentration en coliformes fécaux de l’effluent a été négativement affectée par les radiations solaires dans les étangs peu profonds et positivement affectée par la concentration en coliformes fécaux de l’influent dans les étangs profonds. Habituellement, les effets associés à l’activité de photosynthèse du phytoplancton étaient bien caractérisés dans les étangs de maturation peu profonds. La concentration en coliformes fécaux a été négativement affectée par le pH dans presque tous les cas. Ce modèle ne s’applique aux étangs anaérobies

    Questão social e interdisciplinaridade : a experiência do curso de especialização em analise da questão social da UFPRLitoral

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    Orientadora: Educadora Msa. Mirian Cristina Lopes.Monografia (especialização) - Universidade Federal do Paraná, Setor Litoral, Curso de Especialização em Questão Social pela Perspectiva Interdisciplinar. Defesa em: 2018.Inclui referênciasResumo : Este artigo aborda a importância do entendimento e da prática da interdisciplinaridade, enquanto diretriz para o aprimoramento pessoal e profissional. Tem como palco de vivência e análise, a trajetória percorrida no Curso de Especialização em Questão Social pela Perspectiva Interdisciplinar da UFPR Litoral, traçando um paralelo com a importância da Interdisciplinaridade para a atuação no Serviço Social. No campo do Serviço Social, a finalidade do artigo é fomentar em meio à categoria profissional, a importância do debate da interdisciplinaridade enquanto estratégia para provocar novas práticas no fazer profissional dos assistentes sociais e demais profissionais da política da assistência social, que possam promover a construção de ações construídas entre coletivos, com coletivos, para coletivos diversos, tendo como objetivo a efetivação da cidadania

    Quantifying microbial methane oxidation efficiencies in two experimental landfill biocovers using stable isotopes

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    Abstract: Stable isotope analyses were performed on gas samples collected within two instrumented biocovers, with the goal of evaluating CH4 oxidation efficiencies (f0). In each of the biocovers, gas probes were installed at four locations and at several depths. One of the biocovers was fed with biogas directly from the waste mass, whereas the other was fed through a gas distribution system that allowed monitoring of biogas fluxes. While the f0 values obtained at a depth of 0.1 m were low (between 0.0 and 25.2%) for profiles with poor aeration, they were high for profiles with better aeration, reaching 89.7%. Several interrelated factors affecting aeration seem to be influencing f0, including the degree of water saturation, the magnitude of the biogas flux, and the temperature within the substrate. Low f0 values do not mean necessarily that little CH4 was oxidized. In fact, in certain cases where the CH4 loading was high, the absolute amount of CH4 oxidized was quite high and comparable to the rate of CH4 oxidation for cases with low CH4 loading and high f0. For the experimental biocover for which the CH4 loading was known, the oxidation efficiency obtained using stable isotopes (f0 = 55.67% for samples taken inside flux chambers) was compared to the value obtained by mass balance (f0 = 70.0%). Several factors can explain this discrepancy, including: the high sensitivity of f0 to slight changes in the isotopic fractionation factor for bacterial oxidation, αox, uncertainties related to mass flow meter readings and to the static chamber method

    School environment associates with lung function and autonomic nervous system activity in children : a cross-sectional study

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    Children are in contact with local environments, which may affect respiratory symptoms and allergic sensitization. We aimed to assess the effect of the environment and the walkability surrounding schools on lung function, airway inflammation and autonomic nervous system activity. Data on 701 children from 20 primary schools were analysed. Lung function, airway inflammation and pH from exhaled breath condensate were measured. Pupillometry was performed to evaluate autonomic activity. Land use composition and walkability index were quantified within a 500 m buffer zone around schools. The proportion of effects explained by the school environment was measured by mixed-effect models. We found that green school areas tended to be associated with higher lung volumes (FVC, FEV1 and FEF25-75%) compared with built areas. FVC was significantly lower in-built than in green areas. After adjustment, the school environment explained 23%, 34% and 99.9% of the school effect on FVC, FEV1, and FEF25-75%, respectively. The walkability of school neighbourhoods was negatively associated with both pupil constriction amplitude and redilatation time, explaining -16% to 18% of parasympathetic and 8% to 29% of sympathetic activity. Our findings suggest that the environment surrounding schools has an effect on the lung function of its students. This effect may be partially mediated by the autonomic nervous system.Peer reviewe

    Measuring skin temperature before, during and after exercise: a comparison of thermocouples and infrared thermography

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    Measuring skin temperature (TSK) provides important information about the complex thermal control system and could be interesting when carrying out studies about thermoregulation. The most common method to record TSK involves thermocouples at specific locations; however, the use of infrared thermal imaging (IRT) has increased. The two methods use different physical processes to measure TSK, and each has advantages and disadvantages. Therefore, the objective of this study was to compare the mean skin temperature (MTSK) measurements using thermocouples and IRT in three different situations: pre-exercise, exercise and post-exercise. Analysis of the residual scores in Bland-Altman plots showed poor agreement between the MTSK obtained using thermocouples and those using IRT. The averaged error was -0.75 °C during pre-exercise, 1.22 °C during exercise and -1.16 °C during post-exercise, and the reliability between the methods was low in the pre- (ICC = 0.75 [0.12 to 0.93]), during (ICC = 0.49 [-0.80 to 0.85]) and post-exercise (ICC = 0.35 [-1.22 to 0.81] conditions. Thus, there is poor correlation between the values of MTSK measured by thermocouples and IRT pre-exercise, exercise and post-exercise, and low reliability between the two forms of measurement

    Time required to stabilize thermographic images at rest

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    Thermography for scientific research and practical purposes requires a series of procedures to obtain images that should be standardized; one of the most important is the time required for acclimatization in the controlled environment. Thus, the objective of this study was to identify the appropriate acclimatization time in rest to reach a thermal balance on young people skin. Forty-four subjects participated in the study, 18 men (22.3 ± 3.1 years) and 26 women (21.7 ± 2.5 years). Thermographic images were collected using a thermal imager (Fluke ®), totaling 44 images over a period of 20 minutes. The skin temperature (TSK) was measured at the point of examination which included the 0 minute, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20. The body regions of interest (ROI) analyzed included the hands, forearms, arms, thighs, legs, chest and abdomen. We used the Friedman test with post hoc Dunn?s in order to establish the time at rest required to obtain a TSK balance and the Mann-Whitney test was used to compare age, BMI, body fat percentage and temperature variations between men and women, considering always a significance level of pmenor que0.05. Results showed that women had significantly higher temperature variations than men (pmenor que0.01) along the time. In men, only the body region of the abdomen obtained a significant variance (pmenor que0.05) on the analyzed period, both in the anterior and posterior part. In women, the anterior abdomen and thighs, and the posterior part of the hands, forearms and abdomen showed significant differences (pmenor que0.05). Based on our results, it can be concluded that the time in rest condition required reaching a TSK balance in young men and women is variable, but for whole body analysis it is recommended at least 10 minutes for both sexes

    The Eastern Lower Tagus Valley Fault Zone in central Portugal : active faulting in a low-deformation region within a major river environment

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    Active faulting in the Lower Tagus Valley, Central Portugal, poses a significant seismic hazard that is not well understood. Although the area has been affected by damaging earthquakes during historical times, only recently has definitive evidence of Quaternary surface faulting been found along the western side of the Tagus River. The location, geometry and kinematics of active faults along the eastern side of the Tagus valley have not been previously studied. We present the first results of mapping and paleoseismic analysis of the eastern strand of the Lower Tagus Valley Fault Zone (LTVFZ). Geomorphological, paleoseismological, and seismic reflection studies indicate that the Eastern LTVFZ is a left-lateral strike-slip fault. The detailed mapping of geomorphic features and studies in two paleoseismic trenches show that surface fault rupture has occurred at least six times during the past 10 ka. The river offsets indicate a minimum slip rate on the order of 0.14–0.24 mm/yr for the fault zone. Fault trace mapping, geomorphic analysis, and paleoseismic studies suggest a maximum magnitude for the Eastern LTVFZ of Mw ~ 7.3 with a recurrence interval for surface ruptures ~ 1.7 ka. At least two events occurred after 1175 ± 95 cal yr BP. Single-event displacements are unlikely to be resolved in the paleoseismic trenches, thus our observations most probably represent the minimum number of events identified in the trenches

    Synthesis, characterization, antibacterial and antitumoral activities of mononuclear zinc complexes containing tridentate amine based ligands with N3 or N2O donor groups

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    The synthesis and characterization of the four zinc(II) complexes [Zn(HL1)Cl-2] (1), [Zn(H2L2)Cl-2](2), [Zn(H2L3)Cl-2] (3) and[Zn(H2L4)Cl-2] (4), where HL1 = (bis-2-pyridylmethyl)amine, H2L2 = (2-hydroxybenzyl- 2-pyridylmethyl) amine, H2L3 = N-2[(pyridine-2-ylmethyl)amino)ethanol, H2L4 = 1-[(pyridine-2-ylmethyl)- amino]-propan-2-ol are reported; (3) and (4) are new while (2) was reported previously but its structure had not been determined. The complexes were characterized by elemental analysis, IR, UV-Vis and NMR spectroscopic, electrospray ionization mass spectrometry (ESI(+)-MS) and tandem mass spectrometry ESI(+)-MS/MS). X-ray diffraction studies were performed for complexes (1)-(3) revealing the presence of mononuclear structures in the solid state. The X-ray analyses of (1) and (3) demonstrate that HL1 and HL2 act as tridentate ligands, while the ligand H2L2 in (2) is bidentate. The cytotoxic properties of the ligands and of all the complexes were examined using human leukemia THP-1, U937 and Molt-4 cells. Complex (4) exhibited the highest cytotoxicity in this series with an IC50 value of 75 +/- 1 mu mol L (1) against U937 cells. Transmission electron microscopy (TEM) reveals ultrastructural changes typical of apoptotic cells. The induction of apoptosis was confirmed by the annexin V assay. The antimicrobial activity of complexes (1)-(4) was also investigated in vitro against four Gram-positive bacteria (ATCC10832, ATCC25923, COL) and the clinical Staphylococcus aureus isolate LSA88 (SEC/SEF/ TSST-1+). Complex (2) showed the most potent inhibitory activity, reaching almost 100% of inhibition against all strains tested. Morphological investigations using TEM indicate that the antibacterial activity of complex (2) may be associated with the inhibition of cell wall and therefore cell division. (C) 2014 Elsevier B. V. All rights reserved

    Patient-physician discordance in assessment of adherence to inhaled controller medication: a cross-sectional analysis of two cohorts

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    We aimed to compare patient's and physician's ratings of inhaled medication adherence and to identify predictors of patient-physician discordance.(SFRH/BPD/115169/2016) funded by Fundação para a Ciência e Tecnologia (FCT); ERDF (European Regional Development Fund) through the operations: POCI-01-0145-FEDER-029130 ('mINSPIRERS—mHealth to measure and improve adherence to medication in chronic obstructive respiratory diseases—generalisation and evaluation of gamification, peer support and advanced image processing technologies') cofunded by the COMPETE2020 (Programa Operacional Competitividade e Internacionalização), Portugal 2020 and by Portuguese Funds through FCT (Fundação para a Ciência e a Tecnologia).info:eu-repo/semantics/publishedVersio
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