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Objective: To investigate the effects of combined exposure to black carbon and lead on the expression of cell adhesion molecules and their regulating microRNAs (miRNAs) in the rat choroid plexus epithelial Z310 cells. Methods: i) Z310 cells were randomly divided into control group, black carbon exposure group, lead exposure group and combined exposure group. The lead exposure group and black carbon exposure group were treated with 10 μmol/L lead acetate and 10 mg/L black carbon, respectively, and the combined exposure group was treated with both in the above doses. After 12.0 hours, the expressions of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and mucosal vascular addressin cell adhesion molecule-1 (MAdCAM-1) in Z310 cells was detected by Western blotting. The expression of miR-326, miR-328-3p and miR-542-3p which regulated ICAM-1 was detected by real-time fluorescent quantitative polymerase chain reaction. ii) Z310 cells or Z310 cells transfected with miRNA-326 mimic were randomly divided into control group, miRNA-326 transfection control group, combined exposure group and miRNA-326 transfection combined exposure group. Cells in the two control groups were not treated. The two combined exposure groups were treated with 10 mg/L black carbon and 10 μmol/L lead acetate for 12.0 hours. The expression of ICAM-1 was detected by Western blotting. Results: i) The relative expression of ICAM-1, VCAM-1 and MAdCAM-1 in the cells of black carbon exposure group and ICAM-1 in the lead exposure group was higher than those in the control group (all P<0.05). The relative expression of ICAM-1 and MAdCAM-1 in the combined exposure group was higher than those in the other three groups (all P<0.05). The relative expression of VCAM-1 in cells of combined exposure group was higher than those in the control group and lead exposed group (all P<0.05). The relative expression of miR-326 in cells of the lead exposure group and black carbon exposure group was lower than those in the control group (all P<0.05). The relative expression of miR-326 in the combined exposure group was lower than that in the other three groups (all P<0.05). There was no significant difference between miR-328-3p and miR-542-3p in the four groups (all P>0.05). ii) The relative expression of ICAM-1 in cells of the miR-326 transfection control group cells was lower than that in the control group (P<0.05), while in the cells in the combined exposure and miRNA-326 transfection combined exposure group, it was higher than that in the control and miRNA-326 transfection control groups (all P<0.05), and lower in the miRNA-326 transfection combined exposure group than in the combined exposure group (P<0.05). Conclusion: Black carbon or lead exposure can upregulate the expression of ICAM-1, VCAM-1 and MAdCAM-1 in Z310 cells. Black carbon and lead combined exposure lead to a synergistic effect on upregulation of ICAM-1 and MAdCAM-1 expression, particularly ICAM-1. The combined exposure of black carbon and lead may upregulate the expression of ICAM-1 by downregulating the expression of miR-326.
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Black carbon (BC) is the most strongly light-absorbing component of particulate matter and is largely emitted from the incomplete combustion of fossil and biomass fuels. It has a graphite structure with less carbonized, irregular, microcrystalline, and heterogeneous components, which is determined by pyrolysis conditions. BC can be absorbed by human body via inhalation or ingestion route and then be transported to various organs through the blood circulation system in human body. When crossing different biological barriers (such as blood-brain barrier, placenta barrier, and blood-testis barrier), BC may further act on these targets and induce various toxicities. This review first distinguished between BC and carbon black, and then introduced analytical methods of BC in various environmental samples: microscopic observation, chemothermal oxidation methods, other chemical oxidation methods, and molecular marker analysis. We summarized the principles, technical characteristics, and application to environmental samples of these methods, and discussed the ideas and perspectives of determination of BC in biological samples for human biomonitoring.
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Objective:Exposure to pollutants may induce aggravation of asthma in children through various ways.Ambient black carbon(BC)is a typical pollutant in Northeast China, and there has been no research report on the relationship between atmospheric BC exposure and childhood asthma in Northeast China.This study is to investigate the association between the atmospheric concentration of BC and hospital visits of daily childhood asthma.Methods:During the period of January 1 to August 31 in 2019, 52 653 hospital visits of childhood asthma children were recorded in several hospitals in Shenyang.A time series analysis was conducted to explore the relationship between the atmospheric concentration of BC and hospital visits of daily childhood asthma.Results:During the study period, the total number of children with asthma in outpatient and emergency departments in Shenyang was 52 653, the average concentration of BC was 2.58 mg/m 3.Increased concentrations of BC(2.00~10.03 mg/m 3)( RR=1.17, 95% CI: 1.07~1.28)and NO 2(0~88 μg/m 3)( RR=1.21, 95% CI: 1.06~ 1.39)were significantly associated with elevated number of childhood asthma in outpatient and emergency departments( P< 0.05). The highest cumulative effect of increased pollutants on children′s asthma within 10 days was BC( RR=1.60, 95% CI: 1.23~2.08). Conclusion:There is a positive association between BC concentration and hospital visits of childhood asthma, the accumulative effect of BC on childhood asthma is greater than other pollutants.
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Background: To study,estimate and discuss the variations of the aerosol optical depth (AOD),black carbon,sulfate and organic matter,in the atmosphere in Blida City of Algeria,which was greatly affected by COVID-19 pandemic.Methods: We analyzed the effects of changes in the total AOD,black carbon,sulfate,and organic matter in the atmosphere (λ =550 nm) in the same period of 2019 and 2020,following the COVID-19 epidemic in Blida City,which was the most-affected city in Algeria.Results: The quarantine that was enacted to limit the spread of COVID-19 resulted in side effects that were identifiable in the total AOD and in some of its atmospheric components.Comparing these variables in 2019 and 2020 (in the months during the quarantine) revealed that in April,the BCAOD values were much lower in 2020than in 2019.Conclusion: Based on the effects of the emerging COVID-19,the research listed the changes received from the AOD,and is considered as a comparative study and represents a significant side effect of the quarantine that was mainly designed to limit COVID-19.
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Abstract Biochar (BCH) is a solid product, rich in carbon, obtained by heating biomass under controlled conditions of oxygenation, in a process known as pyrolysis. Its benefits are associated with improvements to the physical, chemical and biological properties of soil. Furthermore, BCH can affect the growth of phytopathogenic microorganisms. Despite research advances in this area, there is still a lack of information on the effect of BCH concentration on different soilborne microorganisms. This work evaluated the direct effect of sewage sludge biochar (SSB) on the in vitro growth of different soilborne fungi. Eight phytopathogens [Fusarium oxysporum, F. oxysporum f. sp. lycopersici (CEN 1456), Macrophomina phaseolina (429), Sclerotinia sclerotiorum, S. sclerotiorum (CEN 1147), Sclerotium rolfsii (CEN 216), Sclerotium cepivorum (CEN 1357), Rhizoctonia solani] were evaluated. Additionally, a biological control agent [Trichoderma afroharzianum (T-22)] was also studied. Microorganisms were subjected to growth in PDA (Potato-Dextrose-Agar) culture medium enriched with SSB. Biochars, produced at 300 and 500 ºC, were applied at different doses: 0.0 (control), 0.2, 0.4, 0.6, 0.8 and 1.0 (g of SSB/100 ml of PDA). Biochars showed inhibitory effects on the mycelial growth of the different fungi evaluated. It was observed that there is a certain specificity of biochar concentration that must be evaluated for the control of phytopathogens. In most cases, the 0.4 and 0.6% concentrations had a greater inhibitory effect on phytopathogens and did not affect the biological control agent. Therefore, SSB proved to be a promising product for the control of different soilborne phytopathogens.
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Aims: Soil black carbon (BC) has been shown to possess large amounts of cation exchange sites and surface charge, and is viewed as a potential soil amendment to improve nutrient retention and for pollutant remediation. This study investigated the nanoscale distribution of reactive functional groups and the binding of cations on the surface of micron-size BC particles, identified the key processes, and explored the sources of surface functionality and their relative contribution to cation exchange capacity (CEC). Materials and Methods: Elemental microprobe and synchrotron-based Scanning Transmission X-ray Spectromicroscopy (STXM) coupled with Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy were used for nano-scale mapping of cations and reactive functional groups, and further distinction of the sources of reactive functional groups generated either by oxidation of BC surfaces or by adsorption of non- BC organic matter onto the BC surfaces. Their respective contribution to cation adsorption was obtained using a depth profile of a BC-rich Anthrosol from the central Amazon, Brazil. Results and Discussion: Adsorption of Non-BC organic matter is more dominant on the surface of BC particle in topsoil as evidenced by a stronger signal of microbial biomass and humic substances extracts. In comparison, a greater level of oxidation was found on the outerlayer of BC particles in subsoil horizons. Organic C in subsoils was found to generate 23-42% more CEC per unit C than topsoil. Based on CEC per unit C, the capacity of BC in creating CEC was 6-7 times higher than Non-BC, and the BC in deeper horizons had up to 20% higher CEC than the topsoil horizon. Near BC surfaces, higher ratios of Ca/C and K/C in subsoil than topsoil horizons reinforce the observation that BC in subsoil horizons had a higher capacity in binding cations and creating CEC than in the topsoil horizon. Conclusions: Oxidation of BC is suggested to be more efficient and important for creating CEC than the adsorption of non-BC onto BC surfaces, thus identified as being key for BC surface functionality and nutrient retention in Amazon Anthrosols.
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Atualmente a comunidade científica discute as diferenças de padrões climáticos entre o leste e o oeste antártico. Enquanto de forma geral observa-se instabilidade no setor oeste, o clima da antártica oriental demonstra relativa estabilidade climática. Abordando este contexto, neste estudo analisamos dois testemunhos de gelo recente de duas regiões com características climáticas diferentes do continente Antártico. No Platô Detroit situado na Península Antártica (64o10'S/060o0'O), analisamos a variabilidde de Black Carbon (BC) ao longo de 20 metros de neve. O BC encontrado na Península Antártica apresentou baixas concentrações comparáveis as encontradas no gelo do Artico período pré-industrial. Nossos resultados sugerem que sua variabilidade corresponde à sazonalidade dos períodos de queimada nos continentes do Hemisfério Sul. No interior do continente Antártico, analisamos o particulado em geral por um processo de microanálise ao longo de um testemunho de 40 metros extraído em Mont Johns (79o55'S/094o23'O). Encontramos uma tendência negativa na deposição de poeira mineral (AISi) entre 1967 e 2007. Nossos resultados sugerem que esta tendência seja resultado de um crescente isolamento dos ventos ao redor da Antártica. Este aumento na intensidade dos ventos reflete por sua vez o resfriamento da alta atmosfera no centro antártico causado pela depleção da camada de ozônio na região. Adicionalmente, amostras de diferentes microambientes de Patriot Hills (80o18'S/081o21'O) foram coletadas de maneira asséptica para análise microbiológica. As amostras foram cultivadas em meio R2 e paralelamente o DNA total extraído foi sequenciado pela técnica de pirosequenciamento. Os resultados preliminares desta análise mostram grande riqueza de espécies dos mais variados grupos. Os resultados deste trabalho caracterizam três diferentes parâmetros relacionados a deposição atmosférica em duas áreas do continente antártico pouco exploradas e de grande interesse científico...
The antarctic ice cap stores paleoclimatological information within layers of snow and ice. Antarctic ice has revealed the higher resolution paleoclimactic database for the last 800 kyr. Atmospheric transport plays a fundamental role on the composition and sources of particulate matter found in the Antarctic ice. It has been related to several climatic processes that changes the quantity and quality of exogenous aerosols reaching Antarctica. Therefore, studies of the particulate matter deposits along the snow/ice layers may suggest changes on atmospheric transport patterns. This work, analyze two recent ice cores from two climatic distinct regions of the Antarctic continent. One retrieved from Detroit Plateau/Antarctic Peninsula (64o10'S/060o0'W), in which we have analyze Black Carbon (BC) deposition and variability along 20 meters of snow. BC found in the Antarctic Peninsula showed low concentrations (varing between 0,014 and 3,733ppb), comparable to the concentrations found on Arctic ice dated from before the industrial revolution period. Our results suggest that peaks of BC detected correspond, mostly, to biomass burning seasons in the South Hemosphere, not speficically from South America. The second one, of 40 m, was retrieved from Central-West Antarctica, Mont Johns (79o55'S/094o23'W), in which we analyzed the mineral dust abundance thought M.E.V. - E.D.X. technique. In this study we found negative trends in mineral dust (inferred from Fe, Ti and AISi) deposition between 1967 and 2007, in contrast to similar works in Sub-antarctic regions. We demonstrate that this trend is a consequence of the persistent "atmospheric isolation" that encloses the Central and East Antarctic regions due to the increasing winds around Antarctica within this period. It has been documented that westerlies intensification reflect the upper atmosphere cooling above Central Antarctica caused by the stratospherical ozone layer depletion. As part of the polar site...
Sujet(s)
Régions antarctiques , Analyse de séquence d'ADN/méthodes , Atmosphère/analyse , Atmosphère/composition chimique , Météorologie , Carbone/composition chimique , Glace/analyse , Minéraux/analyse , Poussière/analyse , Polluants atmosphériques/analyse , Surveillance de l'environnement , Écosystème Glacial , Polluants environnementaux/analyseRÉSUMÉ
Sugarcane ethanol is the most commercially developed liquid biofuel. The potential emissions of Kyoto and non-Kyoto Protocol climate active compounds in the production of sugarcane ethanol in agricultural lands are evaluated herein. Various scenarios are considered, such as low or high N2O emission from N-fertilizers, inclusion or not of pre-harvest burning, uncontrolled or controlled emissions in bagasse based boilers, and 20 or 100 years time horizons in GWPs. The CO2 emitted in ethanol fuel combustion is recycled during sugarcane "re-growing" and does not count as greenhouse gas. However, even though many uncertainties remain, the available information allows estimating that CO2-eq emissions are very large when ethanol production is based on pre-harvest burning and there is non-controlled particle emission in boilers. In these scenarios, compared with the combustion of equivalent amounts of gasoline, higher CO2-eq emission would take place. Halting sugarcane field burning would not be sufficient to revert the situation, especially in a 20-years time horizon. Only when more environmental friendly procedures are applied, a significant saving of CO2-eq emissions occurs at 20 and 100-years horizon scenarios. In all scenarios, non-Kyoto Protocol compounds make an important net contribution. Therefore, if a real evaluation of climate active compounds emissions is to be reached, it would be crucial to include these compounds in life cycles studies. To reduce uncertainties, especially of non-Kyoto compounds, additional research is needed.
El etanol producido de caña de azúcar es el biocombustible más desarrollado comercialmente. En este trabajo se evalúan las emisiones de compuestos climáticamente activos, incluidos y no incluidos en el Protocolo de Kyoto. Se consideran varios escenarios, tales como bajas o altas emisiones de N2O por fertilización con N, inclusión o no de quema pre-cosecha, emisiones controladas o no en las calderas que utilizan bagazo, y horizontes de 20 o 100 años en los GWPs. El CO2 emitido en la combustión de bioetanol es reciclado en la resiembra de la caña de azúcar y no cuenta como gas de invernadero. Sin embargo, a pesar de muchas incertidumbres, la información disponible permite estimar que las emisiones de CO2-eq son altas cuando se realiza quema precosecha y no hay control de las emisiones de las calderas. En estos escenarios ocurrirían emisiones de CO2-eq mayores que las correspondientes a la combustión de una cantidad equivalente de gasolina. Eliminar la quema precosecha no sería suficiente para revertir la situación, especialmente cuando se considera un horizonte de 20 años. Solo si se realizasen procedimientos ambientales más amigables habría ahorro significativo en emisiones de CO2-eq (a 20 y 100 años). En todos los escenarios, los compuestos no incluidos en el Protocolo de Kyoto contribuyen significativamente. Por ello, para evaluar el impacto real de los compuestos climáticamente activos es crucial incluir estos compuestos en los estudios de ciclo de vida. Para reducir las incertidumbres, especialmente las relacionadas con compuestos no incluidos en el Protocolo, se requieren investigaciones adicionales.
O etanol produzido de cana de açúcar é o bio-combustivel mais desenvolvido comercialmente. Neste trabalho se avaliam as emissões de compostos climaticamente ativos, incluídos e não incluídos no Protocolo de Kyoto. Consideram-se vários cenários, tais como baixas ou altas emissões de N2O por fertilização com N, inclusão ou não de queima pré-colheita, emissões controladas ou não nas caldeiras que utilizam bagaço, e horizontes de 20 ou 100 anos nos GWPs. O CO2 emitido na combustão de bioetanol é reciclado na replantação da cana de açúcar e não conta como gás de invernadeiro. No entanto, a pesar de muitas incertezas, a informação disponível permite estimar que as emissões de CO2-eq são altas quando se realiza queima pré-colheita e não há controle das emissões das caldeiras. Nestes cenários ocorreriam emissões de CO2-eq maiores que as correspondentes a combustão de uma quantidade equivalente de gasolina. Eliminar a queima pré-colhita não seria suficiente para reverter a situação, especialmente quando se considera um horizonte de 20 anos. Somente si se realizassem procedimentos ambientais mais amigáveis haveria poupança significativa em emissões de CO2-eq (a 20 e 100 anos). Em todos os cenários, os compostos não incluídos no Protocolo de Kyoto contribuem significativamente. Por isto, para avaliar o impacto real dos compostos climaticamente ativos é crucial incluir estes compostos nos estudos de ciclo de vida. Para reduzir as incertezas, especialmente às relacionadas com compostos não incluídos no Protocolo, se requerem investigações adicionais.