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1.
Bioresour Technol ; 343: 126094, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34624473

RESUMO

Links between carbon/nitrogen (C/N) ratio, synergy and microbial characteristics of anaerobic co-digestion of food waste (FW), cattle manure (CS) and corn straw (CS) were investigated. Digesters with 100% CS, 25% FW + 75% CS, 25% CM + 75% CS suffered acid inhibition, in close association with unbalanced C/N and the resulting recessions of Syntrophomonadaceae and Methanosaeta. Co-digestion overcame C/N imbalance and achieved multiple synergies. Process performance had a positive correlation with Syntrophomonadaceae. Digester with 75% FW + 25% CS had most Syntrophomonadaceae (26.7%) and methane yield (467.3-507.6 mL/g VS) among co-digestion trials. Synergy was greater under higher load and exhibited a good correlation with C/N ratio. Co-digestion of FW, CM and CS (2:2:1) with suitable C/N ratio (20.79) obtained the greatest synergistic rate (14.6%). Unstable systems were improved by adjusting C/N ratio to 30 via urea, which stimulated Methanosarcina growth therefore enhanced methanogenic pathway diversity and ensured powerful methanogenic functions.


Assuntos
Esterco , Eliminação de Resíduos , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Carbono , Bovinos , Digestão , Alimentos , Metano , Nitrogênio , Zea mays
2.
EBioMedicine ; 74: 103649, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34814051

RESUMO

BACKGROUND: Shotgun metagenomics has been used clinically for diagnosing infectious diseases. However, most technical assessments have been limited to individual sets of reference standards, experimental workflows, and laboratories. METHODS: A reference panel and performance metrics were designed and used to examine the performance of shotgun metagenomics at 17 laboratories in a coordinated collaborative study. We comprehensively assessed the reliability, key performance determinants, reproducibility, and quantitative potential. FINDINGS: Assay performance varied significantly across sites and microbial classes, with a read depth of 20 millions as a generally cost-efficient assay setting. Results of mapped reads by shotgun metagenomics could indicate relative and intra-site (but not absolute or inter-site) microbial abundance. INTERPRETATION: Assay performance was significantly impacted by the microbial type, the host context, and read depth, which emphasizes the importance of these factors when designing reference reagents and benchmarking studies. Across sites, workflows and platforms, false positive reporting and considerable site/library effects were common challenges to the assay's accuracy and quantifiability. Our study also suggested that laboratory-developed shotgun metagenomics tests for pathogen detection should aim to detect microbes at 500 CFU/mL (or copies/mL) in a clinically relevant host context (10^5 human cells/mL) within a 24h turn-around time, and with an efficient read depth of 20M. FUNDING: This work was supported by National Science and Technology Major Project of China (2018ZX10102001).

3.
Eur J Clin Microbiol Infect Dis ; 40(9): 1851-1861, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33792806

RESUMO

This study aims to evaluate the clinical value of PCR-fluorescent probes for detecting the mutation gene associated with extensively drug-resistant tuberculosis (XDR-TB). The molecular species identification of 900 sputum specimens was performed using polymerase chain reaction (PCR)-fluorescent probe. The mutations of the drug resistance genes rpoB, katG, inhA, embB, rpsL, rrs, and gyrA were detected. The conventional drug susceptibility testing (DST) and PCR-directed sequencing (PCR-DS) were carried out as control. DST demonstrated that there were 501 strains of rifampicin resistance, 451 strains of isoniazid resistance, 293 strains of quinolone resistance, 425 strains of streptomycin resistance, 235 strains of ethambutol resistance, and 204 strains of amikacin resistance. Furthermore, 427 (47.44%) or 146 (16.22%) strains were MDR-TB or XDR-TB, respectively. The mutations of the rpoB, katG, inhA, embB, rpsL, rrs, and gyrA genes were detected in 751 of 900 TB patients by PCR-fluorescent probe method, and the rate of drug resistance was 751/900 (83.44%). No mutant genes were detected in the other 149 patients. Compared with DST, the mutant rates of rpoB, katG/inhA, rpsL, rrs, embB, and gyrA of six drugs were higher than 88%; five of six drugs were higher than 90% except for SM (88.11%). The MDR and XDR mutant gene types were found in 398 (42.22%) and 137 (15.22%) samples. PCR-DS was also employed and confirmed the PCR-fluorescent probe method with the accordance rate of 100%. The PCR-fluorescent probe method is rapid and straightforward in detecting XDR-TB genotypes and is worthy of being applied in hospitals.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Corantes Fluorescentes/normas , Mutação , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/normas , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Corantes Fluorescentes/metabolismo , Corantes Fluorescentes/farmacologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Escarro/microbiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-33804117

RESUMO

Fine particulate matter (PM2.5) samples were collected in the summer and winter of 2015 and 2017 in Xinxiang, China. Nine polycyclic aromatic hydrocarbons (PAHs) and three nitro-PAHs (NPAHs) in PM2.5 were detected via high-performance liquid chromatography (HPLC). The PAHs concentration in summer and winter decreased from 6.37 ± 1.30 ng/m3 and 96.9 ± 69.9 ng/m3 to 4.89 ± 2.67 ng/m3 and 49.8 ± 43.4 ng/m3 from 2015 to 2017. NPAHs decreased in winter (from 1707 ± 708 pg/m3 to 1192 ± 1113 pg/m3), but increased in summer from 2015 (336 ± 77.2 pg/m3) to 2017 (456 ± 312 pg/m3). Diagnostic ratios of PAHs indicated that petroleum combustion was the main emission source in summer, and pollutants originating from the combustion of petroleum, coal and biomass dominated in winter. The 2-nitrofluoranthene (2-NFR)/2-nitropyrene (2-NP) ratio in this study demonstrated that the OH radical pathway was the main pathway for the formation of 2-NP and 2-NFR. The mean total benzo[a]pyrene-equivalent concentrations (BaPeq) and incremental lifetime cancer risk (ILCR) values decreased from 2013 to 2017. The high value of total BaPeq in the winter of 2017 in Xinxiang revealed that a high-risk of cancer remained for residents. The results of this study demonstrate that the decreases in PAHs and NPAHS concentrations from 2015 to 2017. Combined with reducing gaseous pollutants concentration, the reduction in this study might be attributable to emissions reductions by implementing the air pollution control regulations in Xinxiang city in 2016.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Estações do Ano
5.
Artigo em Inglês | MEDLINE | ID: mdl-33803562

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are a class of important organic pollutants widely emitted from anthropogenic activities, with a general distribution in the gas and particulate phases. Some PAHs are carcinogenic, teratogenic, and mutagenic. Inhalation exposure to PAHs is correlated with adverse health outcomes in the respiratory and cardiovascular systems. Thus, it is significant to determine the exposure level of the general population. This study summarizes the evaluation methods for PAH exposure, focusing on different exposure parameters. External exposure can be determined via the collection of the environmental pollution concentration through active samplers or passive samplers during environmental monitoring or personal sampling. Time-activity patterns give critical exposure information that captures the exposure period, origin, and behaviors. Modeling is a labor-less approach for human exposure estimation, and microenvironmental exposure requires specific research. It is important to select appropriate methods to quantify the exposure level to provide accurate data to establish the exposure-risk relationship and make scientific suggestions for the protection of public health.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Humanos , Exposição por Inalação/análise , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco
6.
Artigo em Inglês | MEDLINE | ID: mdl-33672189

RESUMO

Particulate matter (PM) is a major factor contributing to air quality deterioration that enters the atmosphere as a consequence of various natural and anthropogenic activities. In PM, polycyclic aromatic hydrocarbons (PAHs) represent a class of organic chemicals with at least two aromatic rings that are mainly directly emitted via the incomplete combustion of various organic materials. Numerous toxicological and epidemiological studies have proven adverse links between exposure to particulate matter-bound (PM-bound) PAHs and human health due to their carcinogenicity and mutagenicity. Among human exposure routes, inhalation is the main pathway regarding PM-bound PAHs in the atmosphere. Moreover, the concentrations of PM-bound PAHs differ among people, microenvironments and areas. Hence, understanding the behaviour of PM-bound PAHs in the atmosphere is crucial. However, because current techniques hardly monitor PAHs in real-time, timely feedback on PAHs including the characteristics of their concentration and composition, is not obtained via real-time analysis methods. Therefore, in this review, we summarize personal exposure, and indoor and outdoor PM-bound PAH concentrations for different participants, spaces, and cities worldwide in recent years. The main aims are to clarify the characteristics of PM-bound PAHs under different exposure conditions, in addition to the health effects and assessment methods of PAHs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Humanos , Compostos Orgânicos , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
7.
Chem Pharm Bull (Tokyo) ; 69(3): 237-245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642471

RESUMO

As a background sampling site in western Japan, the Kanazawa University Wajima Air Monitoring Station (KUWAMS) continuously observes the air pollutants, including PM1, PM2.5, organic carbon (OC) and element carbon (EC). Data for September 2019 to April 2020 were compared with data for September 2018 to April 2019. The mean concentrations of both PM1 and PM2.5 were 4.10 µg/m3 (47%) and 5.82 µg/m3 (33%) lower, respectively in the Coronavirus Disease 2019 (COVID-19) period (January to April) than in the same period in 2019. Notably, the average concentrations of both classes of particulate matter (PM) in the COVID-19 period were the lowest for that period in all years since 2016. OC and EC also considerably lower (by 69 and 63%, respectively) during the COVID-19 period than during the same period in 2019. All pollutants were then started to increase after the resumption of the work in 2020. The pollutant variations correspond to the measure implemented during the COVID-19 period, including the nationwide lockdown and work resumption. Furthermore, the reductions in the ratios PM1/PM2.5 and OC/EC during COVID-19 period indicate lighter pollution and fewer emission sources. This analysis of the changes in the pollutant concentrations during the epidemic and non-epidemic periods illustrates the significance of the dominant pollution emissions at KUWAMS and the impact of pollution from China that undergoes long-range transport to KUWAMS.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , COVID-19 , Pandemias , Carbono/análise , China , Monitoramento Ambiental , Japão , Tamanho da Partícula , Material Particulado/análise , Quarentena
8.
Zhongguo Zhong Yao Za Zhi ; 46(2): 454-466, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645135

RESUMO

In this study, Honghua Injection, Danshen Injection, Shenkang Injection, Shuxuetong Injection, Lulutong Injection, Shenxiong Glucose Injection and Chuanxiong Injection were compared for their clinical efficacy on chronic renal insufficiency by using the method of network Meta-analysis, with Western medicine as the common reference. The randomized controlled trial(RCT) of Hong-hua Injection, Danshen Injection, Shenkang Injection, Shuxuetong Injection, Lulutong Injection, Shenxiong Glucose Injection and Chuanxiong Injection for the treatment of chronic renal insufficiency were obtained by computer-based retrieval. The literature quality was evaluated by using the method in Cochrane Reviewer's Handbook 5.1 after independent screening of the included literature by two reviewers. The RJAGS package and GEMTC package of RevMan 5.3, GEMTC software, R software were used for statistical analysis to compare and sort the different injections in terms of efficacy. A total of 6 197 patients with chronic renal failure were included in 79 RCTs, involving 8 treatment measures. The effective rates of conventional treatment combined with Shenxiong Injection(OR=3.55, 95%CI[1.98, 6.37], P<0.000 1), Honghua Injection(OR=3.77, 95%CI[2.45, 5.81], P<0.000 01), Shuxuetong Injection(OR=6.71, 95%CI[3.30, 13.65], P<0.000 01) and Shenkang Injection(OR=4.14, 95%CI[3.42, 5.03], P<0.000 01) were all better than that in control group, and the effective rate of Honghua Injection combined with conventional treatment(OR=3.89, 95%CI[1.73, 8.74], P=0.001) was better than that in Danshen Injection combined with conventional treatment, all with statistically significant differences. By comprehensive comparison, Shuxuetong Injection, Honghua Injection and Shenkang Injection combined with Western medicine had good clinical effect on the effective rate, serum creatinine reduction and urea nitrogen reduction in patients with chronic renal insufficiency. However, due to the relatively low quality of the included literature, the conclusion has yet to be verified clinically.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Renal Crônica , Salvia miltiorrhiza , Teorema de Bayes , Humanos , Medicina Tradicional Chinesa , Metanálise em Rede , Insuficiência Renal Crônica/tratamento farmacológico
9.
Clin Chem ; 67(4): 672-683, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33788940

RESUMO

BACKGROUND: Infectious disease outbreaks such as the COVID-19 (coronavirus disease 2019) pandemic call for rapid response and complete screening of the suspected community population to identify potential carriers of pathogens. Central laboratories rely on time-consuming sample collection methods that are rarely available in resource-limited settings. METHODS: We present a highly automated and fully integrated mobile laboratory for fast deployment in response to infectious disease outbreaks. The mobile laboratory was equipped with a 6-axis robot arm for automated oropharyngeal swab specimen collection; virus in the collected specimen was inactivated rapidly using an infrared heating module. Nucleic acid extraction and nested isothermal amplification were performed by a "sample in, answer out" laboratory-on-a-chip system, and the result was automatically reported by the onboard information platform. Each module was evaluated using pseudovirus or clinical samples. RESULTS: The mobile laboratory was stand-alone and self-sustaining and capable of on-site specimen collection, inactivation, analysis, and reporting. The automated sampling robot arm achieved sampling efficiency comparable to manual collection. The collected samples were inactivated in as short as 12 min with efficiency comparable to a water bath without damage to nucleic acid integrity. The limit of detection of the integrated microfluidic nucleic acid analyzer reached 150 copies/mL within 45 min. Clinical evaluation of the onboard microfluidic nucleic acid analyzer demonstrated good consistency with reverse transcription quantitative PCR with a κ coefficient of 0.979. CONCLUSIONS: The mobile laboratory provides a promising solution for fast deployment of medical diagnostic resources at critical junctions of infectious disease outbreaks and facilitates local containment of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) transmission.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Laboratórios , Unidades Móveis de Saúde , Patologia Molecular/métodos , RNA Viral/análise , Adulto , Automóveis , COVID-19/epidemiologia , Teste de Ácido Nucleico para COVID-19/instrumentação , Feminino , Humanos , Dispositivos Lab-On-A-Chip , Masculino , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Coronavírus da Síndrome Respiratória do Oriente Médio/química , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/métodos , Pandemias , Patologia Molecular/instrumentação , Robótica , SARS-CoV-2/química
10.
Bioresour Technol ; 329: 124919, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33676353

RESUMO

Links between synergy and microbial community characteristics in co-digestion of food waste (FW), cattle manure (CM) and corn straw (CS) were investigated. Mono-digestion of FW and CS were inhibited by organic acids. Co-digestion of FW with CM achieved greater synergistic rates (18.5% and 22.3%) than CM with CS (14.8% and 12.3%). Synergy resulted from coupling effects of improving nutrient balance, dilution of toxic compounds, higher buffering capacity, detoxification based on co-metabolism, which ultimately reflected in microbial community functions. Although co-digestion of FW with CS exhibited lowest synergistic rates (7.9% and 4.9%), detoxification based on co-metabolism of syntrophic communities of Syntrophomonadaceae with hydrogenotrophic methanogens accelerated system recovery. Digester with the greatest synergy (65% FW + 35% CM) maintained dominant growth of hydrogenotrophic methanogens (68.9%), highest methanogenic community diversity and relative abundance of Methanosarcina (14.6%), which sustained more diverse and switchable methanogenic pathways therefore ensured powerful methanogenic functions and vigorous methanogenic capability.


Assuntos
Microbiota , Eliminação de Resíduos , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Bovinos , Digestão , Alimentos , Esterco , Metano , Zea mays
11.
Artigo em Inglês | MEDLINE | ID: mdl-33466956

RESUMO

Kirishima is a typical Japanese commercial city, famous for frequent volcanic activity. This is the first study to determine the characteristics of PM2.5-bound polycyclic and nitro-polycyclic aromatic hydrocarbons (PAHs and NPAHs) and water-soluble inorganic ions (WSIIs) in this city. In this study, the non-volcanic eruption period was taken as the target and daily PM2.5 samples were collected from 24 November to 21 December 2016. The daily concentrations in PM2.5 of Æ©PAHs, Æ©NPAHs, and Æ©WSIIs ranged from 0.36 to 2.90 ng/m3, 2.12 to 22.3 pg/m3, and 1.96 to 11.4 µg/m3, respectively. Through the results of the diagnostic ratio analyses of the PAHs, NPAHs, and WSIIs and the backward trajectory analysis of the air masses arriving in Kirishima, the emission sources of PAHs, NPAHs, and WSIIs in PM2.5 in Kirishima were influenced by the coal burning that came from the East Asian continent, although there was no influence from volcanic emission sources during the sampling period. The total benzo[a]pyrene (BaP)-equivalent concentration was lower than many other cities but the health risks in Kirishima were nonetheless notable. These findings are very important for future research on PM samples during the inactive Asian monsoon and volcanic eruption periods, to further understand the characteristics of air pollutants in Kirishima, and to contribute to the improvement in health of residents and a reduction in the atmospheric circulation of air pollutants in East Asia.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Cidades , Monitoramento Ambiental , Extremo Oriente , Íons , Japão , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano , Água
12.
J Environ Sci (China) ; 99: 72-79, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183718

RESUMO

This study encompassed the regular observation of nine polycyclic aromatic hydrocarbons (PAHs) and three nitro-PAHs (NPAHs) in particulate matter (PM) in Shanghai in summer and winter from 2010 to 2018. The results showed that the mean concentrations of Æ©PAHs in summer decreased by 24.7% in 2013 and 18.1% in 2017 but increased by 10.2% in 2015 compared to the data in 2010. However, the mean concentrations of Æ©PAHs in winter decreased by 39.7% from 2010 (12.8 ± 4.55 ng/m3) to 2018 (7.72 ± 3.33 ng/m3), and the mean concentrations of 1-nitropyrene in winter decreased by 79.0% from 2010 (42.3 ± 16.1 pg/m3) to 2018 (8.90 ± 2.09 pg/m3). Correlation analysis with meteorological conditions revealed that the PAH and NPAH concentrations were both influenced by ambient temperature. The diagnostic ratios of PAHs and factor analysis showed that they were mainly affected by traffic emissions with some coal and/or biomass combustion. The ratio of 2-nitrofluoranthene to 2-nitropyrene was near 10, which indicated that the OH radical-initiated reaction was the main pathway leading to their secondary formation. Moreover, backward trajectories revealed different air mass routes in each sampling period, indicating a high possibility of source effects from the northern area in winter in addition to local and surrounding influences. Meanwhile, the mean total benzo[a]pyrene-equivalent concentrations in Shanghai in winter decreased by 50.8% from 2010 (1860 ± 645 pg/m3) to 2018 (916 ± 363 pg/m3). These results indicated the positive effects of the various policies and regulations issued by Chinese authorities.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano
13.
Chemosphere ; 264(Pt 1): 128427, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33002800

RESUMO

Eleven years (2005-2015) of data from long-term monitoring at a Japanese remote background site in Wajima, were analyzed to investigate temporal trends and sources. Water-soluble inorganic ions (WSIIs) were analyzed for aerosol chemical composition. The total WSIIs concentration was 7.93 ± 3.93 µg/m3, accounting for 42.3% of TSP mass, ranged from 11.4 to 93.9%. SO42- is the most abundant ion, contributing a total WSII mass from 18.0 to 79.8%, and non-sea-salt (nss-) SO42- contributed from 63.6% to 99.6% of total SO42-, which was related to human activities on the Asian continent and the effects of marine precursors in spring and summer, respectively. NO3- and NH4+ contribute 6.3 and 7.4% of the total WSIIs and were affected by long-range transport and local sources as well. The increasing trend of Na+ and Cl- indicates the increased influence of sea salt, which is caused by more frequent strong winds. K+ is mainly produced from biomass burning with a stable seasonal variation, Ca2+ as the characteristic ion of dust has the highest concentration in spring. Mg2+ comes from minerals and marine sources during spring and summer, respectively. This work describes in detail the annual change trend of the WSIIs of atmospheric particles in the Wajima area, seasonal characteristics, and source contributions, provide a comprehensive understanding of long-term variation in atmospheric particulate.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Humanos , Íons/análise , Japão , Material Particulado/análise , Estações do Ano
14.
J Environ Manage ; 279: 111772, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310238

RESUMO

This study investigated responses of anaerobic digestion (AD) of food waste (FW) with different inocula to varying organic loads and to pH control under high load in terms of process performance and microbial characteristics. Without pH control, digester inoculated by thickened sludge obtained high methane yield of 547.8 ± 27.8 mL/g VS under organic load of 7.5 g VS/L but was inhibited by volatile fatty acids (VFAs) under higher loads (15 and 30 g VS/L). However, digesters inoculated by anaerobic sludge obtained high methane yields of 575.9 ± 34.2, 569.3 ± 24.8 and 531.9 ± 26.2 mL/g VS under organic loads of 7.5, 15 and 30 g VS/L and VFAs inhibition only appeared under extremely high load of 45 g VS/L. Digesters under VFA inhibition with high load were significantly enhanced by controlling single ecological factor pH at 6.5, 7.0 and 7.5, as indicated by shorter lag phases, higher peak values of methane production rate, greater methane yields and fast VFAs degradation. Maximum methane recovery was obtained with pH control at 7.5 under high load. VFA inhibition was accompanied by the degeneration of ecological functions of Syntrophomonadaceae and unidentified Bacteroidales and the dominant growth of unidentified Clostridiales. Under high load and pH control, high stability was strongly associated with obvious growth of Methanosarcina, which enriched methanogenic pathways thus improved system robustness and tolerance to VFAs. Moreover, pH control stimulated the growth of syntrophic Bacteria Syntrophomonadaceae while maintaining the high activity of hydrogenotrophic methanogens therefore sustained efficient syntrophic communities of Bacteria and methanogens and avoided over accumulation of VFAs. pH control promoted adaptive selection of methanogens, leading to obvious decline of archaeal community diversity. This study provided practical guidance on digester configurations of high-load AD of FW and expanded the understanding of responses to coupling effects of inoculum origins, organic loads and pH control under high load concerning process performance and microbial community dynamics.


Assuntos
Reatores Biológicos , Eliminação de Resíduos , Anaerobiose , Alimentos , Concentração de Íons de Hidrogênio , Metano
15.
Artigo em Inglês | MEDLINE | ID: mdl-33172174

RESUMO

Daily PM2.5 (particulate matter with aerodynamic diameter ≤2.5 µm) samples were simultaneously collected at two background sites (Wajima Air Monitoring Station (WAMS) and Fukue-Jima Atmosphere and Aerosol Monitoring Station (FAMS)) in Japan in the East Asian winter and summer monsoon periods of 2017 and 2019, to compare the characteristics of air pollutants among different regions and to determine the possible variation during the long-range transport process. Polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and water-soluble inorganic ions (WSIIs) were analyzed. Despite the PM2.5 concentrations at FAMS (8.90-78.5 µg/m3) being higher than those at WAMS (2.33-21.2 µg/m3) in the winter monsoon period, the average concentrations of ∑PAHs, ∑NPAHs, and ∑WSIIs were similar between the two sites. Diagnostic ratios indicated PAHs mainly originated from traffic emissions and mostly aged, whereas NPAHs were mostly secondarily formed during long-range transport. WSIIs at WAMS were mainly formed via the combustion process and secondary reactions, whereas those at FAMS mainly originated from sea salt and dust. Backward trajectories revealed the air masses could not only come from Asian continental coastal regions but also distant landlocked areas in the winter monsoon period, whereas most came from the ocean in the summer monsoon period. These findings can provide basic data for the establishment of prediction models of transboundary air pollutants in East Asia.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Humanos , Íons , Japão , Estações do Ano , Água
16.
ACS Omega ; 5(44): 28597-28605, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33195911

RESUMO

The structure of a Ni/Al2O3 monolithic catalyst after methanation reaction and its methanation performance were studied by taking analogue syngas of biomass gasification H2/CO/N2 as feed gas when the temperature ranged from 250 to 550 °C, and the weight hourly space velocity (WHSV) was between 6000 and 14,000 mL g-1 h-1. The Ni/Al2O3 catalysts using cordierite honeycomb ceramics as the substrate were prepared by dipping and sol-gel methods. The results show that the Ni/Al2O3 catalyst prepared by the dipping method (DIP-Ni/Al2O3) has better methanation performance than the Ni/Al2O3 catalyst prepared by the sol-gel method (SG-Ni/Al2O3) through many tests such as TEM, BET, XRD, H2-TPD, H2-TPR, and TG analysis. The DIP-Ni/Al2O3 catalyst exhibits the best methanation performance at 400 °C when the molar ratio of H2, CO, and N2 is 3/1/1 and the WHSV is 10,000 mL g-1 h-1. Under this condition, the CO conversion and CH4 selectivity are 98.6 and 90.9%, respectively. In addition, the methanation performance of the DIP-Ni/Al2O3 catalyst is relatively more stable, and the CO conversion and CH4 selectivity were basically maintained at around 90% within the experimental WHSV range. The influence of Ni content on the methanation performance of the DIP-Ni/Al2O3 catalyst can be seen in the order from high to low of methanation performance: 15% Ni, 20% Ni, and 10% Ni, and the maximum values of CO conversion and CH4 selectivity reach 96.8 and 96%, respectively, at 400 °C for 15% Ni/Al2O3.

17.
Bioresour Technol ; 315: 123796, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32682261

RESUMO

Role of trace elements (TEs) in long-term anaerobic digestion of food waste (FW) under fixed and stepwise increasing loads and under early and medium volatile fatty acid (VFA) inhibition was investigated. Digesters under high load suffered VFA inhibition. Mismatch between scarce TEs in FW and essential TEs for sustainable methanogenesis suppressed Methanosaeta causing blocked aceticlastic methanogenesis and shift to CO2 reduction pathway, as indicated by decreased Methanosaeta from above 70.0% to below 42.0% and enriched hydrogenotrophic methanogens (Methanospirillum, Methanoculleus, Methanobacterium) from below 15.0% to above 53.6%. Dual stresses of VFA inhibition and TEs deficiency resulted in recession of syntrophic Bacteria Syntrophomonadaceae. Conversely, digesters with TEs supplementation maintained high activity of Syntrophomonadaceae and ensured predominant aceticlastic methanogenesis and powerful methanogenic community functions. Early and medium VFA inhibition were reversed by TEs supplementation or coupling with pH adjustment by stimulating VFAs degradation via syntrophic metabolism and unclogging acetate conversion via aceticlastic methanogenesis.


Assuntos
Microbiota , Eliminação de Resíduos , Oligoelementos , Anaerobiose , Reatores Biológicos , Metano
18.
ACS Omega ; 5(19): 11138-11146, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32455236

RESUMO

We present the adsorption data of CO2, CH4, and N2 ternary mixtures on anthracite from 293.15 to 353.15 K and pressures up to 7 MPa obtained via a volumetric method. The experimental data are given at different conditions, and simple analysis is made. The results show that the excess adsorption capacity of the CO2/CH4/N2 mixture and its component gases decreases linearly with the increase of temperature for constant composition. The total adsorption capacity is between pure CO2 and pure N2 in the entire pressure range. The effect of total pressure on total adsorption capacity is mainly influenced by the CO2 mole fraction in the feed gas. However, the adsorption capacities of CH4 and N2 decrease, and CO2 presents a maximum with the decrease in total pressure. For the feed gases of 10% CH4 and 16% CO2, the total adsorption capacity increases when the ratio of CO2 and CH4 increases, respectively, and the increasing magnitudes for 10% CH4 are larger than that of 16% CO2. The obtained experimental data are in agreement with the extended three-parameter Ono-Kondo model.

19.
Environ Pollut ; 263(Pt A): 114454, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32247922

RESUMO

Natural aeolian dust (AD) particles are potential carriers of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere. The heterogeneous interaction between them may lead to worsened air quality and enhanced cytotoxicity and carcinogenicity of ambient particulates in downwind areas, and this topic requires in-depth exploration. In this study, AD samples were collected from four Asian dust sources, and their physical properties and compositions were determined, showing great regional differences. The physical and chemical interactions of different AD particles with naphthalene (Nap; model PAH) were observed in aqueous systems. The results showed that AD particles from the Loess Plateau had weak adsorption to Nap, which was fitted by the Langmuir isotherm. There was no obvious adsorption to Nap found for the other three AD samples. This difference seemed to depend mainly on the specific surface area and/or the total pore volume. In addition, the Nap in the aqueous solution did not undergo chemical reactions under dark conditions and longwave ultraviolet (UV) radiation but degraded under shortwave UV radiation, and 2-formylcinnamaldehyde and 1,4-naphthoquinone were the first-generated products. The degradation of Nap in the aqueous solution was probably initiated by photoionization, and the reaction rate constant (between 1.44 × 10-4 min-1 and 8.55 × 10-4 min-1) was much lower than that of Nap with hydroxyl radicals. Instead of inducing or promoting the chemical change in Nap, the AD particles slowed photodegradation due to the extinction of radiation. Therefore, it is inferred that natural AD particles have no substantial effect on the transportation and transformation of PAHs in the atmosphere.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Atmosfera , Carvão Mineral/análise , Poeira/análise , Naftalenos
20.
Medicine (Baltimore) ; 99(17): e18704, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32332593

RESUMO

BACKGROUND: Hypoxic ischemic encephalopathy (HIE) is brain injury caused by different reasons and the most common diagnosed is neonatal HIE. Most of the existing treatments have their own shortcomings or there are still some unexplained mechanisms in it. Topiramate (TPM) is a new drug for the treatment for seizures in neonates with HIE, but is currently used off-label. Our protocol aims to access the efficiency and safety of TPM for HIE. METHODS AND ANALYSIS: Eight databases will be searched by 2 independent researchers for the article on the topic of using TPM as treatment for HIE, including PubMed, the Cochrane Central Register of Controlled Trials (Cochrane Library), Embase, and Web of Science, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), Wang Fang Database and Chinese Science and Technology Periodical database (VIP). The included papers are those published from the established date of the databases to 2019. The therapeutic effects based on the grade of neonatal behavioral neurological assessment will be regarded as the primary outcomes. RevMan V5.3 will be used to compute the data synthesis and carry out meta-analysis. The risk of bias will be appraised by the Cochrane risk of bias tool. Rare ratio for dichotomous outcomes and mean different for continuous data will be expressed with 95% confidence intervals (CI) for analysis. A random effects model or a fixed effects model will be employed, when heterogeneity is found or not. Subgroup analysis and sensitivity analysis will be applied if the heterogeneity is obvious. RESULTS: This study will provide the recent evidence of TPM for HIE from reducing seizure acticity. CONCLUSION: The conclusion of this study will provide proof to evaluate if TPM is effective and safe in the treatment of HIE.PROSPERO registration number: PROSPERO CRD42018117981.


Assuntos
Anticonvulsivantes/uso terapêutico , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Topiramato/uso terapêutico , Anticonvulsivantes/efeitos adversos , Humanos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/mortalidade , Recém-Nascido , Estresse Oxidativo/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Convulsões/tratamento farmacológico , Convulsões/etiologia , Índice de Gravidade de Doença , Topiramato/efeitos adversos
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