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1.
Int J Environ Health Res ; : 1-13, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041841

RESUMO

Evidence on the impacts of PM1, PM2.5, and PM10 on the hospital admissions, length of hospital stays (LOS), and hospital expenses among patients with cardiovascular disease (CVD) is still limited in China, especially in rural areas. This study was performed in eight counties of Fuyang from 1 January 2015 to 30 June 2017. We use a three-stage time-series analysis to explore the effects of short-term exposure to PM1, PM2.5, and PM10 on hospital admissions, LOS, and hospital expenses for CVDs. An increment of 10 ug/m3 in PM1, PM2.5, and PM10 corresponded to an increment of 1.82% (95% CI: 1.34, 2.30), 0.96% (95% CI: 0.44, 1.48), and 0.79% (95% CI: 0.63%, 0.95%) in CVD hospital admissions, respectively. We observed that daily concentrations of PMs were associated with an increase in hospital admissions, LOS, and expenses for CVDs. Sustained endeavors are required to reduce air pollution so as to attenuate disease burdens from CVDs.

2.
Sci Total Environ ; 945: 174136, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38901578

RESUMO

Dioxins and the emerging dioxin-like compounds (DLCs) have recruited increasing concerns about their environmental contamination, toxicity, health impacts, and mechanisms. Based on the structural similarity of dioxins and many DLCs, their toxicity was predominantly mediated by the dioxin receptor (aryl hydrocarbon receptor, AHR) in animals (including human), which can be different in expression and function among species and then possibly produce the species-specific risk or toxicity. To date, characterizing the AHR of additional species other than human and rodents can increase the accuracy of toxicity/risk evaluation and increase knowledge about AHR biology. As a key model, the medaka AHR has not been clearly characterized. Through genome survey and phylogenetic analysis, we identified four AHRs (olaAHR1a, olaAHR1b, olaAHR2a, and olaAHR2b) and two ARNTs (olaARNT1 and olaARNT2). The medaka AHR pathway was conserved in expression in nine tested tissues, of which olaAHR2a represented the predominant subform with greater abundance. Medaka AHRs and ARNTs were functional and could be efficiently transactivated by the classical dioxin congener 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), although olaAHR1a did not seem to cooperate with olaARNT2. In terms of function/sensitivity, the EC50 values of medaka olaAHR1a (9.01 ± 1.43 nM), olaAHR1b (4.00 ± 1.10 nM), olaAHR2a (8.75 ± 3.34 nM), and olaAHR2b (3.06 ± 0.81 nM) showed slight differences; however, they were all at the nM level. The sensitivity of four medaka AHRs to TCDD was similar to that of zebrafish dreAHR2 (the dominant form, EC50 = 3.14 ± 4.19 nM), but these medaka AHRs were more sensitive than zebrafish dreAHR1b (EC50 = 27.05 ± 18.51 nM). The additional comparison also indicated that the EC50 values in various species were usually within the nM range, but AHRs of certain subforms/species can vary by one or two orders of magnitude. In summary, the present study will enhance the understanding of AHR and help improve research on the ecotoxicity of dioxins/DLCs.


Assuntos
Dioxinas , Oryzias , Receptores de Hidrocarboneto Arílico , Poluentes Químicos da Água , Peixe-Zebra , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Dioxinas/toxicidade , Poluentes Químicos da Água/toxicidade , Filogenia , Especificidade da Espécie
3.
J Environ Manage ; 352: 120051, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38262282

RESUMO

With the rapid growth of the metallurgical industry, there is a significant increase in the production of metallurgical slags. The waste slags pose significant challenges for their disposal because of complex compositions, low utilization rates, and environmental toxicity. One promising approach is to utilize metallurgical slags as catalysts for treatment of refractory organic pollutants in wastewater through advanced oxidation processes (AOPs), achieving the objective of "treating waste with waste". This work provides a literature review of the source, production, and chemical composition of metallurgical slags, including steel slag, copper slag, electrolytic manganese residue, and red mud. It emphasizes the modification methods of metallurgical slags as catalysts and the application in AOPs for degradation of refractory organic pollutants. The reaction conditions, catalytic performance, and degradation mechanisms of organic pollutants using metallurgical slags are summarized. Studies have proved the feasibility of using metallurgical slags as catalysts for removing various pollutants by AOPs. The catalytic performance was significantly influenced by slags-derived catalysts, catalyst modification, and process factors. Future research should focus on addressing the safety and stability of catalysts, developing green and efficient modification methods, enhancing degradation efficiency, and implementing large-scale treatment of real wastewater. This work offers insights into the resource utilization of metallurgical slags and pollutant degradation in wastewater.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Águas Residuárias , Cobre , Substâncias Perigosas , Metalurgia , Oxirredução , Poluentes Químicos da Água/análise
4.
PLoS One ; 18(12): e0295022, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38127917

RESUMO

At present, potato seeders in China generally have poor uniformity of seed rows and high coefficients of variation in plant spacing during seed rows, causing difficulties for subsequent mechanized plant protection and harvesting. Based on the effect of seed discharge to analyze the sowing process, a potato seed discharger with a double-layer seed picking spoon structure was designed. By analyzing the seed discharging mechanism and its operation process, the shape and size structural parameters of the seed picking spoon were determined. Finite element simulation of the seed pickup process and seed carrying process of the seed discharging mechanism was carried out by EDEM software to determine the double-layer seed scoop scheme and the range of factors for subsequent tests. A two-factor test was conducted with seeding line speed and seed drop height as test factors, and plant spacing coefficient of variation and seed potato lateral offset dispersion as test indexes. The test results showed that the double-layer seeding spoon chain seeder reduced the coefficient of variation in plant spacing by 5.8%, and the dispersion in lateral offset by 5.5 mm, compared with the single seeding spoon seeder, when the seeding speed was 0.184 m/s and the height of falling seed was 9 cm.

5.
Nat Commun ; 14(1): 6334, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816727

RESUMO

N6-methyladenosine (m6A) modification of gene transcripts plays critical roles in cancer. Here we report transcriptomic m6A profiling in 98 tissue samples from 65 individuals with pancreatic ductal adenocarcinoma (PDAC). We identify 17,996 m6A peaks with 195 hyper-methylated and 93 hypo-methylated in PDAC compared with adjacent normal tissues. The differential m6A modifications distinguish two PDAC subtypes with different prognosis outcomes. The formation of the two subtypes is driven by a newly identified m6A regulator CSTF2 that co-transcriptionally regulates m6A installation through slowing the RNA Pol II elongation rate during gene transcription. We find that most of the CSTF2-regulated m6As have positive effects on the RNA level of host genes, and CSTF2-regulated m6As are mainly recognized by IGF2BP2, an m6A reader that stabilizes mRNAs. These results provide a promising PDAC subtyping strategy and potential therapeutic targets for precision medicine of PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , RNA Mensageiro/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a RNA/genética , Neoplasias Pancreáticas
6.
Sci Total Environ ; 904: 166622, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37647967

RESUMO

Tetrabromobisphenol A (TBBPA) is a widely used plastic additive with high bioaccumulation potential and toxicity on both humans and wildlife. Currently, research on its ecotoxicity and the underlying mechanism is limited. Using common carp (Cyprinus carpio), we evaluated the toxicity of TBBPA, especially focusing on its alteration of a key metabolism-related pathway aryl hydrocarbon receptor (AHR), using in vivo/vitro assays and in silico simulation. The 96 h LC50 of TBBPA of common carp was 4.2 mg/L and belonged to the acute toxic level II. The bioaccumulation potential of TBBPA follows the role of liver > gill > brain and varies between 3- and 14-day exposure. On the AHR pathway respect, as expected, the metabolism-related cyp1a1 and cyp1b1 were upregulated in the liver and brain. Ahr2, the receptor, was also upregulated in the brain under TBBPA exposure. The alteration of gene expression was tissue-specific while the difference between 3- or 14-day exposure was minor. AHR inhibition assay indicated the 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)-induced AHR transactivation can be inhibited by TBBPA suggesting it is not a potent agonist but a competitive antagonist. In silico analysis indicated TBBPA can be successfully docked into the binding cavity with similar poses but still have AHR-form-specific interactions. Molecular dynamics simulation proved TBBPA can be more flexible than the coplanar ligand TCDD, especially in ccaAHR1b with greater root-mean-square deviation (RMSD), of which TCDD-induced transactivation seemed not to be blocked by TBBPA. This research increased the understanding of TBBPA toxicity and alteration of the AHR pathway, and pointed out the need to perform additional toxicology evaluation of emerging contaminants, especially on non-model species.


Assuntos
Carpas , Dibenzodioxinas Policloradas , Animais , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo , Carpas/metabolismo , Fígado/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Citocromo P-450 CYP1A1/metabolismo
7.
Chemosphere ; 337: 139404, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37399998

RESUMO

The release of untreated wastewater into water bodies has become a significant environmental concern, resulting in the accumulation of refractory organic pollutants that pose risks to human health and ecosystems. Wastewater treatment methods, including biological, physical, and chemical techniques, have limitations in achieving complete removal of the refractory pollutants. Chemical methods, particularly advanced oxidation processes (AOPs), have gained special attention for their strong oxidation capacity and minimal secondary pollution. Among the various catalysts used in AOPs, natural minerals offer distinct advantages, such as low cost, abundant resources, and environmental friendliness. Currently, the utilization of natural minerals as catalysts in AOPs lacks thorough investigation and review. This work addresses the need for a comprehensive review of natural minerals as catalysts in AOPs. The structural characteristics and catalytic performance of different natural minerals are discussed, emphasizing their specific roles in AOPs. Furthermore, the review analyzes the influence of process factors, including catalyst dosage, oxidant addition, pH value, and temperature, on the catalytic performance of natural minerals. Strategies for enhancing the catalytic efficiency of AOPs mediated by natural minerals are explored, mainly including physical fields, reductant addition, and cocatalyst utilization. The review also examines the practical application prospects and main challenges associated with the use of natural minerals as heterogeneous catalysts in AOPs. This work contributes to the development of sustainable and efficient approaches for organic pollutant degradation in wastewater.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Humanos , Águas Residuárias , Poluentes Químicos da Água/análise , Ecossistema , Minerais/química , Oxirredução
8.
Chemosphere ; 335: 139154, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37290502

RESUMO

Diflubenzuron has been applied in agriculture and aquaculture, and its residues in ecological environment and food chain could result in chronic exposure and long-term toxicity effects for human health. However, limited information is available regarding diflubenzuron levels in fish and associated risk assessment. This study performed the analysis for dynamic bioaccumulation and elimination distribution of diflubenzuron in carp tissues. The results indicated that diflubenzuron was absorbed and enriched by fish body along with higher enrichment in lipid-rich tissues of fish. The peak concentration in carp muscle reached 6-fold of diflubenzuron concentration in aquaculture water. The median lethal concentration (LC50) of diflubenzuron at 96 h was 12.29 mg/L, presented low toxicity to carp. Risk assessment results showed that the chronic risk from dietary exposure to diflubenzuron through carp consumption for Chinese residents of children and adolescents, adults and elderly people were acceptable, while posed a certain risk for young children. This study provided the reference for pollution control, risk assessment and scientific management of diflubenzuron.


Assuntos
Carpas , Diflubenzuron , Poluentes Químicos da Água , Animais , Criança , Humanos , Idoso , Pré-Escolar , Adolescente , Diflubenzuron/toxicidade , Poluentes Químicos da Água/toxicidade , Bioacumulação , Poluição Ambiental
9.
Pharmaceutics ; 15(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37111757

RESUMO

Osteoarthritis (OA) is an inflammation-driven degenerative joint disease. Human salivary peptide histatin-1 (Hst1) shows pro-healing and immunomodulatory properties. but its role in OA treatment is not fully understood. In this study, we investigated the efficacy of Hst1 in the inflammation modulation-mediated attenuation of bone and cartilage damage in OA. Hst1 was intra-articularly injected into a rat knee joint in a monosodium iodoacetate (MIA)-induced OA model. Micro-CT, histological, and immunohistochemical analyses showed that Hst1 significantly attenuates cartilage and bone deconstruction as well as macrophage infiltration. In the lipopolysaccharide-induced air pouch model, Hst1 significantly reduced inflammatory cell infiltration and inflammation. Enzyme-linked immunosorbent assay (ELISA), RT-qPCR, Western blot, immunofluorescence staining, flow cytometry (FCM), metabolic energy analysis, and high-throughput gene sequencing showed that Hst1 significantly triggers M1-to-M2 macrophage phenotype switching, during which it significantly downregulated nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinases (MAPK) signaling pathways. Furthermore, cell migration assay, Alcian blue, Safranin O staining, RT-qPCR, Western blot, and FCM showed that Hst1 not only attenuates M1-macrophage-CM-induced apoptosis and matrix metalloproteinase expression in chondrogenic cells, but it also restores their metabolic activity, migration, and chondrogenic differentiation. These findings show the promising potential of Hst1 in treating OA.

10.
Environ Sci Pollut Res Int ; 30(18): 51412-51421, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36809617

RESUMO

Most of studies relating ambient nitrogen dioxide (NO2) exposure to hospital admissions for cardiovascular diseases (CVDs) were conducted among urban population. Whether and to what extent these results could be generalizable to rural population remains unknown. We addressed this question using data from the New Rural Cooperative Medical Scheme (NRCMS) in Fuyang, Anhui, China. Daily hospital admissions for total CVDs, ischaemic heart disease, heart failure, heart rhythm disturbances, ischaemic stroke, and haemorrhagic stroke in rural regions of Fuyang, China, were extracted from NRCMS between January 2015 and June 2017. A two-stage time-series analysis method was used to assess the associations between NO2 and CVD hospital admissions and the disease burden fractions attributable to NO2. In our study period, the average number (standard deviation) of hospital admissions per day were 488.2 (117.1) for total CVDs, 179.8 (45.6) for ischaemic heart disease, 7.0 (3.3) for heart rhythm disturbances, 13.2 (7.2) for heart failure, 267.9 (67.7) for ischaemic stroke, and 20.2 (6.4) for haemorrhagic stroke. The 10-µg/m3 increase of NO2 was related to an elevated risk of 1.9% (RR: 1.019, 95% CI: 1.005 to 1.032) for hospital admissions of total CVDs at lag0-2 days, 2.1% (1.021, 1.006 to 1.036) for ischaemic heart disease, and 2.1% (1.021, 1.006 to 1.035) for ischaemic stroke, respectively, while no significant association was observed between NO2 and hospital admissions for heart rhythm disturbances, heart failure, and haemorrhagic stroke. The attributable fractions of total CVDs, ischaemic heart disease, and ischaemic stroke to NO2 were 6.52% (1.87 to 10.94%), 7.31% (2.19 to 12.17%), and 7.12% (2.14 to 11.85%), respectively. Our findings suggest that CVD burdens in rural population are also partly attributed to short-term exposure to NO2. More studies across rural regions are required to replicate our findings.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Isquemia Encefálica , Doenças Cardiovasculares , Insuficiência Cardíaca , Acidente Vascular Cerebral Hemorrágico , AVC Isquêmico , Isquemia Miocárdica , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/epidemiologia , Dióxido de Nitrogênio/análise , Poluição do Ar/análise , Isquemia Encefálica/epidemiologia , População Rural , Acidente Vascular Cerebral/epidemiologia , China/epidemiologia , Isquemia Miocárdica/epidemiologia , Poluentes Atmosféricos/análise , Material Particulado/análise , Exposição Ambiental/análise
11.
Cranio ; 41(5): 432-439, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33350359

RESUMO

OBJECTIVE: To investigate the correlation between basic characteristics and clinical features of patients with temporomandibular disorders (TMD). METHODS: The R language statistical tool was used to analyze the clinical information of 500 TMD patients, i.e., age, sex, joint noises, mouth opening pattern, and pain symptoms, as well as the results of the mandibular push-back test. A pairwise correlation analysis of each clinical feature was carried out. RESULTS: The highest incidence of TMD was observed in the age group of 20 to 30 years (240/500). Around 2/3 of the patients showed pain symptoms. Abnormal mouth opening patterns, joint noises, and temporomandibular joint synovitis (TMJS) were observed in 48.4, 65.4, and 34% of patients, respectively. CONCLUSION: Joint click and the corrected deviation of the mouth opening pattern are signs of early-stage TMD, whereas limited mouth opening and TMJS are indicators of progressive stage and complicated TMD.


Assuntos
Transtornos da Articulação Temporomandibular , Humanos , Adulto Jovem , Adulto , Transtornos da Articulação Temporomandibular/complicações , Transtornos da Articulação Temporomandibular/epidemiologia , Transtornos da Articulação Temporomandibular/diagnóstico , Articulação Temporomandibular , Dor , Mandíbula , Demografia
12.
Build Environ ; 207: 108413, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36568650

RESUMO

To control the transport of particles such as the SARS-CoV-2 virus in airliner cabins, which is a significant concern for the flying public, effective ventilation systems are essential. Validated computational fluid dynamics (CFD) models are frequently and effectively used to investigate air distribution and contaminant transportation. The complex geometry and airflow characteristics in airliner cabins pose a challenge to numerical CFD validation. The objective of this investigation was to identify accurate and affordable validation processes for studying the airflow field and particulate contaminant distribution in airliner cabins during the design process for different ventilation systems. This study quantitatively evaluated the effects of ventilation system, turbulence model, particle simulation method, geometry simplification, and boundary condition assignment on airflow and particulate distributions in airliner cabins with either a mixing ventilation (MV) system or a displacement ventilation (DV) system calculated by CFD. The results showed that among four turbulence models, the standard k-ε, RNG k-ε, realizable k-ε and SST k-ω models, the prediction by the realizable k-ε model agreed most closely with the experimental data. Meanwhile, the steady Eulerian method provided a reasonable prediction of the particle concentration field with low computing cost. The computational domain should be simplified differently for the DV system and the MV system with consideration of the simulation accuracy and computing cost. For more accurate modeling results, the boundary conditions should be assigned in greater detail, taking into account the uniformity on the boundary.

13.
Comput Intell Neurosci ; 2022: 2982894, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35942464

RESUMO

The study of plantar pressure has become a research consensus in the field of biomechanics. The purpose of this paper is to study some lower limb movements in the daily activities of ice and snow athletes to obtain relevant data so as to carry out gait recognition analysis research. This paper selects the average foot pressure, forefoot foot pressure, front and rear foot pressure, foot pressure, toe pressure, 2-5 toe pressure, standing with eyes closed, x- and y-axes speed, foot length, foot width, and other actions of ice and snow athletes. Therefore, correlation analysis, work analysis, and curve fitting analysis were carried out on the joint motion in a single gait cycle. The collection and application of foot pressure and foot posture information are also analyzed. According to the plantar structure, the sole is divided into four parts. The maximum pressure point and coordinates of each part, the pressure center point, the ratio of the width and height of the sole of the foot, and so on are extracted as the haptic features of the gait. The experimental data shows that it can be seen that if the plantar area is divided in advance and the weight of each area is marked, whether standing, walking, or standing with one leg closed eyes can achieve better recognition results, and the accuracy rate is all more than 90 percent. The average recognition accuracy rate using the method of dividing four regions is only about 80%, and the accuracy rate of recognition using the method of dividing eight regions is 82%. It can be seen that the features extracted by the FCM model proposed in this paper contain more information of the plantar pressure image, and the accuracy rate is higher in the classification and recognition.


Assuntos
Gelo , Neve , Atletas , Fenômenos Biomecânicos , Marcha , Humanos , Pressão , Caminhada
14.
Regen Biomater ; 9: rbab075, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480858

RESUMO

Dicalcium silicate (Ca2SiO4, C2S) has osteogenic potential but induces macrophagic inflammation. Mitochondrial function plays a vital role in macrophage polarization and macrophagic inflammation. The mitochondrial function of C2S-treated macrophages is still unclear. This study hypothesized: (i) the C2S modulates mitochondrial function and autophagy in macrophages to regulate macrophagic inflammation, and (ii) C2S-induced macrophagic inflammation regulates osteogenesis. We used RAW264.7 cells as a model of macrophage. The C2S (75-150 µg/ml) extract was used to analyze the macrophagic mitochondrial function and macrophage-mediated effect on osteogenic differentiation of mouse bone marrow-derived mesenchymal stem cells (BMSCs). The results showed that C2S extract (150 µg/ml) induced TNF-α, IL-1ß and IL-6 production in macrophages. C2S extract (150 µg/ml) enhanced reactive oxygen species level and intracellular calcium level but reduced mitochondrial membrane potential and ATP production. TEM images showed reduced mitochondrial abundance and altered the mitochondrial morphology in C2S (150 µg/ml)-treated macrophages. Protein level expression of PINK1, Parkin, Beclin1 and LC3 was upregulated but TOMM20 was downregulated. mRNA sequencing and KEGG analysis showed that C2S-induced differentially expressed mRNAs in macrophages were mainly distributed in the essential signaling pathways involved in mitochondrial function and autophagy. The conditioned medium from C2S-treated macrophage robustly promoted osteogenic differentiation in BMSCs. In conclusion, our results indicate mitochondrial dysfunction and autophagy as the possible mechanism of C2S-induced macrophagic inflammation. The promotion of osteogenic differentiation of BMSCs by the C2S-induced macrophagic inflammation suggests the potential application of C2S in developing immunomodulatory bone grafts.

16.
Cranio ; : 1-8, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986737

RESUMO

OBJECTIVE: To study the correlation between condylar morphology and clinical manifestations in patients with degenerative joint disease (DJD) of the temporomandibular joint (TMJ). METHODS: A total of 175 joints of 131 patients with DJD were included. Data on patients' basic information and symptoms were collected and analyzed. Condylar morphology was evaluated using cone beam computed tomography (CBCT). The correlation between the condylar morphology and clinical manifestations was analyzed. RESULTS: The prevalence of joint noises, clicks, and crepitus was 93/175 (53%), 73/175 (42%), and 20/175 (11%), respectively. Condylar anteroposterior diameter and condylar height were correlated with pain. There was a correlation between the shape of the condyle in the sagittal plane and joint noise. CONCLUSION: Condylar morphology and clinical features of DJD were correlated to some extent.

17.
Build Environ ; 208: 108590, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34812218

RESUMO

The air distribution system in an airliner plays a key role in maintaining a comfortable and healthy environment in the aircraft cabin. To evaluate the performance of a novel displacement ventilation (DV) system and a traditional mixing ventilation (MV) system in an airliner cabin, this study conducted experiments and simulations in a seven-row cabin mockup. This investigation used ultrasonic anemometers and T-thermocouples to measure the air velocity, temperature and distribution of 1 µm and 5 µm particles. Simulation verifications were performed for these operating conditions, and additional scenarios with different occurrence source locations were also simulated. This study combined the Wells-Riley equation with a real case based on a COVID-19 outbreak among passengers on a long-distance bus to obtain the COVID-19 quanta value. Through an evaluation of the airflow organization, thermal comfort, and risk of COVID-19 infection, the two ventilation systems were compared. This investigation found that polydisperse particles should be used to calculate the risk of infection in airliner cabins. In addition, at the beginning of the pandemic, the infection risk with DV was lower than that with MV. In the middle and late stages of the epidemic, the infection risk with MV can be reduced when passengers wear masks, leading to an infection risk approximately equal to that of DV.

19.
Sci Rep ; 11(1): 23130, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848765

RESUMO

Sulfamethoxazole (SMX) is the most commonly used antibiotic in worldwide for inhibiting aquatic animal diseases. However, the residues of SMX are difficult to eliminate and may enter the food chain, leading to considerable threats on human health. The bacterial strain Sphingobacterium mizutaii LLE5 was isolated from activated sludge. This strain could utilize SMX as its sole carbon source and degrade it efficiently. Under optimal degradation conditions (30.8 °C, pH 7.2, and inoculum amount of 3.5 × 107 cfu/mL), S. mizutaii LLE5 could degrade 93.87% of 50 mg/L SMX within 7 days. Four intermediate products from the degradation of SMX were identified and a possible degradation pathway based on these findings was proposed. Furthermore, S. mizutaii LLE5 could also degrade other sulfonamides. This study is the first report on (1) degradation of SMX and other sulfonamides by S. mizutaii, (2) optimization of biodegradation conditions via response surface methodology, and (3) identification of sulfanilamide, 4-aminothiophenol, 5-amino-3-methylisoxazole, and aniline as metabolites in the degradation pathway of SMX in a microorganism. This strain might be useful for the bioremediation of SMX-contaminated environment.


Assuntos
Carbono/química , Sphingobacterium/efeitos dos fármacos , Sphingobacterium/fisiologia , Sulfametoxazol/farmacocinética , Antibacterianos/metabolismo , Bactérias/isolamento & purificação , Biodegradação Ambiental , Carbono/metabolismo , Microbiologia Ambiental , Sequenciamento de Nucleotídeos em Larga Escala , Cinética , Redes e Vias Metabólicas , Filogenia , RNA Ribossômico 16S/metabolismo , Esgotos/microbiologia , Sulfonamidas/metabolismo , Temperatura , Poluentes Químicos da Água/metabolismo
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