Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Environ Pollut ; 338: 122679, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37797923

RESUMO

Urban construction activities generate particulate matter (PM), which poses a severe threat to urban residents' quality of life. The complex topography of urban areas and turbulent air flow make it difficult to predict PM dispersion and establish control measures. This study predicted PM dispersion from construction sites to urban areas under four wind directions using CFD simulations and determined optimal dust barrier heights for reducing PM exposure. This study showed that PM exposure on residents depends on wind directions in the urban area up to 2.3 times, still a flexible approach to determine optimal barrier heights based on stakeholder preferences was effective in all wind directions. Accurate PM dispersion predictions and control measures are crucial for improving urban air quality and residents' well-being.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado/análise , Poeira/análise , Poluentes Atmosféricos/análise , Qualidade de Vida , Modelos Teóricos , Monitoramento Ambiental , Poluição do Ar/análise , Vento
2.
Yonsei Med J ; 63(12): 1138-1143, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36444550

RESUMO

PURPOSE: Fusobacterium species can cause infections, and associations with cancer are being increasingly reported. As their clinical significance differs, accurate identification of individual species is important. However, matrix-assisted laser desorption/ionization-time of flight mass spectrometry has not been found to be effective in identifying Fusobacterium species in previous studies. In this study, we aimed to improve the accuracy and efficacy of identifying Fusobacterium species in clinical laboratories. MATERIALS AND METHODS: In total, 229 Fusobacterium isolates were included in this study. All isolates were identified at the species level based on nucleotide sequences of the 16S ribosomal RNA gene and/or DNA-dependent RNA polymerase ß-subunit gene (rpoB). Where necessary, isolates were identified based on whole genome sequences. Among them, 47 isolates were used for updating the ASTA database, and 182 isolates were used for the validation of Fusobacterium spp. identification. RESULTS: Fusobacterium isolates used for validation (182/182) were correctly identified at the genus level, and most (180/182) were correctly identified at the species level using the ASTA MicroIDSys system. Most of the F. nucleatum isolates (74/75) were correctly identified at the subspecies level. CONCLUSION: The updated ASTA MicroIDSys system can identify nine species of Fusobacterium and four subspecies of F. nucleatum in good agreement. This tool can be routinely used in clinical microbiology laboratories to identify Fusobacterium species and serve as a springboard for future research.


Assuntos
Fusobacterium , Laboratórios Clínicos , Humanos , Fusobacterium/genética , Espectrometria de Massas , Bases de Dados Factuais , Lasers
3.
J Hazard Mater ; 403: 123804, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264906

RESUMO

Although various technologies are being developed in the construction industry, management technologies for achieving environmental sustainability in the local community are still lacking. As such, this study suggests future insights for the development of an automated intelligent environment management system for the promotion of environmental sustainability in the local community, through a systematic review of 1,707 relevant literature. The systematic review was conducted in two steps: (i) quantitative review: keyword co-occurrence and trend analysis; and (ii) qualitative review: a review on monitoring, evaluation, and improvement technologies. As a result, the research level related to the local-level pollutants (noise, vibration, and dust) was found to be quantitatively insufficient, and the limitations of the existing technologies for these pollutants were presented. Eventually, to overcome these limitations, new technologies and application strategies that can be applied to construction sites as future research roadmap to effectively manage the hazardous pollutants were proposed. Furthermore, an intelligent management system should be developed, and the management of environmental complaints is also necessary for environmental sustainability at the local level in the construction industry. As a fundamental study, this study could become a benchmark for future researches dealing with environmental sustainability and hazardous pollutants in the construction industry.

4.
J Hazard Mater ; 402: 123483, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-32707465

RESUMO

The management of noise, vibration, and dust, which are hazardous pollutants from construction sites, is essential to minimize the health damage of the nearby residents and the economic damage of construction companies due to pollutants from construction sites. For the effective management of hazardous pollutants, their emissions from construction sites must be identified immediately and accurately. Therefore, this study developed a real-time automated monitoring system named "MOnitoring for Noise, Vibration, and Dust (MONVID)" for comprehensively measuring the hazardous environmental pollutants and managing them in real-time. Toward this end, the optimal design of MONVID was planned and customized considering mobility, usability, and economy. Also, for the field application of the developed MONVID, its feasibility was verified by comparing its techno-economic performance with that of the conventional measurement system through experiments. Based on the results of the experiment and performance evaluation, it was concluded that MONVID is a feasible and economical construction pollutant measurement system with reliable technical performance and improved mobility and usability compared to the conventional measurement system. This study has significant contributions to the development of the first platform (including hardware, sensor network, and software) for the integrated real-time automated monitoring of the environmental performance of construction sites.

5.
J Microbiol Biotechnol ; 29(3): 382-391, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30661322

RESUMO

Many poultry eggs are discarded worldwide because of infection (i.e., avian flu) or presence of high levels of pesticides. The possibility of adopting egg yolk as a source material to produce polyhydroxyalkanoate (PHA) biopolymer was examined in this study. Cupriavidus necator Re2133/pCB81 was used for the production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) or poly(3HHx), a polymer that would normally require long-chain fatty acids as carbon feedstocks for the incorporation of 3HHx monomers. The optimal medium contained 5% egg yolk oil and ammonium nitrate as a nitrogen source, with a carbon/nitrogen (C/N) ratio of 20. Time course monitoring using the optimized medium was conducted for 5 days. Biomass production was 13.1 g/l, with 43.7% co-polymer content. Comparison with other studies using plant oils and the current study using egg yolk oil revealed similar polymer yields. Thus, discarded egg yolks could be a potential source of PHA.


Assuntos
Ácido 3-Hidroxibutírico/biossíntese , Cupriavidus necator/metabolismo , Gema de Ovo/química , Biomassa , Biopolímeros/biossíntese , Biopolímeros/química , Caproatos , Carbono/metabolismo , Meios de Cultura/química , Cupriavidus necator/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , Lipídeos/biossíntese , Lipídeos/química , Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos
6.
Bioprocess Biosyst Eng ; 42(4): 603-610, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30617415

RESUMO

Polyhydroxybutyrates (PHB) are biodegradable polymers that are produced by various microbes, including Ralstonia, Pseudomonas, and Bacillus species. In this study, a Vibrio proteolyticus strain, which produces a high level of polyhydroxyalkanoate (PHA), was isolated from the Korean marine environment. To determine optimal growth and production conditions, environments with different salinity, carbon sources, and nitrogen sources were evaluated. We found that the use of a medium containing 2% (w/v) fructose, 0.3% (w/v) yeast extract, and 5% (w/v) sodium chloride (NaCl) in M9 minimal medium resulted in high PHA content (54.7%) and biomass (4.94 g/L) over 48 h. Addition of propionate resulted in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) copolymer as propionate acts as a precursor for the HV unit. In these conditions, the bacteria produced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) containing a 15.8% 3HV fraction with 0.3% propionate added as the substrate. To examine the possibility of using unsterilized media with high NaCl content for PHB production, V. proteolyticus was cultured in sterilized and unsterilized conditions. Our results indicated a higher growth, leading to a dominant population in unsterilized conditions and higher PHB production. This study showed the conditions for halophilic PHA producers to be later implemented at a larger scale.


Assuntos
Organismos Aquáticos , Poli-Hidroxialcanoatos/biossíntese , Água do Mar/microbiologia , Vibrio , Microbiologia da Água , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Coreia (Geográfico) , Vibrio/genética , Vibrio/isolamento & purificação
7.
Enzyme Microb Technol ; 118: 57-65, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30143200

RESUMO

Glutaric acid is one of the promising C5 platform compounds in the biochemical industry. It can be produced chemically, through the ring-opening of butyrolactone followed by hydrolysis. Alternatively, glutaric acid can be produced via lysine degradation pathways by microorganisms. In microorganisms, the overexpression of enzymes involved in this pathway from E. coli and C. glutamicum has resulted in high accumulation of 5-aminovaleric acid. However, the conversion from 5-aminovaleric acid to glutaric acid has resulted in a relatively low conversion yield for unknown reasons. In this study, as a solution to improve the production of glutaric acid, we introduced gabTD genes from B. subtilis to E. coli for a whole cell biocatalytic approach. This approach enabled us to determine the effect of co-factors on reaction and to achieve a high conversion yield from 5-aminovaleric acid at the optimized reaction condition. Optimization of whole cell reaction by different plasmids, pH, temperature, substrate concentration, and cofactor concentration achieved full conversion with 100 mM of 5-aminovaleric acid to glutaric acid. Nicotinamide adenine dinucleotide phosphate (NAD(P)+) and α-ketoglutaric acid were found to be critical factors in the enhancement of conversion in selected conditions. Whole cell reaction with a higher concentration of substrates gave 141 mM of glutaric acid from 300 mM 5-aminovaleric acid, 150 mM α-ketoglutaric acid, and 60 mM NAD+ at 30 °C, with a pH of 8.5 within 24 h (47.1% and 94.2% of conversion based on 5-aminovaleric acid and α-ketoglutaric acid, respectively). The whole cell biocatalyst was recycled 5 times with the addition of substrates; this enabled the accumulation of extra glutaric acid.


Assuntos
4-Aminobutirato Transaminase/metabolismo , Aminoácidos Neutros/metabolismo , Bacillus subtilis/enzimologia , Escherichia coli/metabolismo , Glutaratos/metabolismo , Succinato-Semialdeído Desidrogenase/metabolismo , 4-Aminobutirato Transaminase/genética , Bacillus subtilis/genética , Biocatálise , Escherichia coli/genética , Succinato-Semialdeído Desidrogenase/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...