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1.
Nano Lett ; 24(5): 1717-1728, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270376

RESUMO

Surgery is the primary method to treat malignant melanoma; however, the residual microtumors that cannot be resected completely often trigger tumor recurrence, causing tumor-related mortality following melanoma resection. Herein, we developed a feasible strategy based on the combinational chemoimmunotherapy by cross-linking carboxymethyl chitosan (CMCS)-originated polymetformin (PolyMetCMCS) with cystamine to prepare stimuli-responsive nanogel (PMNG) owing to the disulfide bond in cystamine that can be cleaved by the massive glutathione (GSH) in tumor sites. Then, chemotherapeutic agent doxorubicin (DOX) was loaded in PMNG, which was followed by a hyaluronic acid coating to improve the overall biocompatibility and targeting ability of the prepared nanogel (D@HPMNG). Notably, PMNG effectively reshaped the tumor immune microenvironment by reprogramming tumor-associated macrophage phenotypes and recruiting intratumoral CD8+ T cells owing to the inherited immunomodulatory capability of metformin. Consequently, D@HPMNG treatment remarkably suppressed melanoma growth and inhibited its recurrence after surgical resection, proposing a promising solution for overcoming lethal melanoma recurrence.


Assuntos
Melanoma , Polietilenoglicóis , Polietilenoimina , Humanos , Nanogéis , Macrófagos Associados a Tumor , Cistamina , Linfócitos T CD8-Positivos , Doxorrubicina , Glutationa/química , Microambiente Tumoral , Linhagem Celular Tumoral
2.
Environ Res ; 246: 118140, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199467

RESUMO

Efficient and precise recovery of phenol from coal chemical wastewater (CCW) poses a significant challenge, prompting the development of a novel aldehyde-based, ester-based hyper-cross-linked polar resin (DES-COOC-CHO) in this study. Two distinct functional group modification methods were employed to enhance the screening effect of the resin. SEM, FT-IR, NMR, XPS, and BET characterizations confirmed the successful construction of the hyper-cross-linked polar resin, incorporation aldehyde and ester groups, exhibiting a special surface area of 627.2 m2/g and a microporous specific surface area percentage of 29.94%. DES-COOC-CHO adhered to the pseudo-second-order kinetic model and Langmuir model (maximum adsorption capacity of 118.0 mg/g). Its adsorption of phenol was spontaneous chemisorption, monolayer adsorption. Notably, even after undergoing 20 adsorption-desorption cycles, the resin maintained a stable adsorption capacity, showcasing excellent recoverability. In the presence of phenols sharing similar properties, DES-COOC-CHO exhibited superior selectivity for phenol. In real CCW, it achieved a remarkable 90% selective removal rate of phenol. The primary selective mechanism relied on the hydrogen bonding effect facilitated by aldehyde and ester groups, coupled with microporous sieving of appropriate size. In comparison with other adsorbent materials, DES-COOC-CHO exhibited superior adsorption properties, coupled with a cost-effective preparation process, presenting significant potential for practical applications.


Assuntos
Fenol , Poluentes Químicos da Água , Águas Residuárias , Adsorção , Carvão Mineral , Espectroscopia de Infravermelho com Transformada de Fourier , Fenóis/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
3.
Environ Res ; 245: 118053, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38160976

RESUMO

The middle reaches of the Yellow River are rich in energy resources, with the Kuye River, a first-class river in this region, serving as a vital hub for the coal chemical industry within China. This study investigated the occurrence patterns, environmental trends, and ecological risks associated with polycyclic aromatic hydrocarbons (PAHs) in the Kuye River Basin, offering insights into the environmental dynamics of regions. The findings indicated that the river sediments primarily contained PAHs with medium to high-molecular weights, exhibiting levels ranging from 402.92 ng/g dw to 16,783.72 ng/g dw, while water bodies predominantly featured PAHs with low to medium molecular weights, ranging from 299.34 ng/L to 10,930.9 ng/L. The source analysis of PAHs indicated that industrial and traffic exhaust emissions were the primary contributors to PAHs in the Kuye basin, with sediments serving as a secondary release source based on fugacity fraction. The content of PAHs in sediment correlated closely with the environmental factors, and the PAHs inventory of the basin was 19.97 tons. The increased overall PAH concentration in the basin posed significant ecological and public health concerns, necessitating urgent attention.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Rios/química , China , Medição de Risco , Água
4.
Environ Geochem Health ; 46(3): 89, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367204

RESUMO

This study systematically analyzed the distribution characteristics, sources, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in Kuye River sediments, located in an energy and chemical industry base in northern Shaanxi, China. The results that revealed the concentrations of 16 PAHs in the sediment ranged from 1090.04 to 32,175.68 ng∙g-1 dw, with the four-ring PAHs accounting for the highest proportion. Positive matrix factorization analysis (PMF) revealed the main sources of PAHs as incomplete fossil fuel combustion, biomass combustion, and traffic emissions. The total toxic equivalent concentration of BaP, risk quotient, and lifetime carcinogenic risk of PAHs suggested moderate to high contamination of PAHs in the area. The higher incremental lifetime carcinogenic risk (ILCR) indicated that PAH ingestion was the primary route of impact on public health, with children potentially being more susceptible to PAH exposure. This study can provide valuable theoretical support for implementing pollution prevention measures and ecological restoration strategies for rivers in energy and chemical industry areas.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Criança , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Indústria Química , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental/métodos , Medição de Risco , China
5.
J Magn Reson Imaging ; 58(1): 247-255, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36259352

RESUMO

BACKGROUND: Radiomics-based analyses have demonstrated impact on studies of endometrial cancer (EC). However, there have been no radiomics studies investigating preoperative assessment of MRI-invisible EC to date. PURPOSE: To develop and validate radiomics models based on sagittal T2-weighted images (T2WI) and T1-weighted contrast-enhanced images (T1CE) for the preoperative assessment of MRI-invisible early-stage EC and myometrial invasion (MI). STUDY TYPE: Retrospective. POPULATION: One hundred fifty-eight consecutive patients (mean age 50.7 years) with MRI-invisible endometrial lesions were enrolled from June 2016 to March 2022 and randomly divided into the training (n = 110) and validation cohort (n = 48) using a ratio of 7:3. FIELD STRENGTH/SEQUENCE: 3-T, T2WI, and T1CE sequences, turbo spin echo. ASSESSMENT: Two radiologists performed image segmentation and extracted features. Endometrial lesions were histopathologically classified as benign, dysplasia, and EC with or without MI. In the training cohort, 28 and 20 radiomics features were selected to build Model 1 and Model 2, respectively, generating rad-score 1 (RS1) and rad-score 2 (RS2) for evaluating MRI-invisible EC and MI. STATISTICAL TESTS: The least absolute shrinkage and selection operator logistic regression method was used to select radiomics features. Mann-Whitney U tests and Chi-square test were used to analyze continuous and categorical variables. Receiver operating characteristic curve (ROC) and decision curve analysis were used for performance evaluation. The area under the ROC curve (AUC), accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated. A P-value <0.05 was considered statistically significant. RESULTS: Model 1 had good performance for preoperative detecting of MRI-invisible early-stage EC in the training and validation cohorts (AUC: 0.873 and 0.918). In addition, Model 2 had good performance in assessment of MI of MRI-invisible endometrial lesions in the training and validation cohorts (AUC: 0.854 and 0.834). DATA CONCLUSION: MRI-based radiomics models may provide good performance for detecting MRI-invisible EC and MI. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias do Endométrio , Imageamento por Ressonância Magnética , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Curva ROC , Valor Preditivo dos Testes , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/cirurgia
6.
Environ Res ; 216(Pt 2): 114589, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244442

RESUMO

This study investigated the culture and characteristics of quinoline-degraded aerobic granular sludge (AGS) under 8-h and 12-h cycle duration. According to results, the cultivation of an 8-h cycle duration enhanced the growth of quinoline-degraded AGS, as well as the settleability of sludge and the retention of biomass. Quinoline can be removed from mature AGS at a rate of more than 90%, but it is removed at a rate slightly higher when the AGS are cultured for 12-h. Compared to 12-h cycle duration, 8-h cycle duration result in a greater increase in the production of extracellular polymeric substances, particularly extracellular proteins. In these two systems, Acidovorax and Paracoccus dominated the quinoline degrading bacteria. In addition, analysis by non-metric multidimensional scaling (based on Bray-curtis distance) showed significant differences of community structure between the two reactors. Clostridia and Acidaminobacter are different bacteria with an 8-h cycle duration compared to 12 h. Relative abundance of nitrogen metabolism genes based on PICRUSt2 prediction, which explain the better total nitrogen removal for an 8-h cycle duration compared to a 12-h cycle duration. Finally, the KEGG pathway was analyzed in order to confirm the results of the microbial analysis.


Assuntos
Microbiota , Quinolinas , Esgotos/microbiologia , Matriz Extracelular de Substâncias Poliméricas , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos , Aerobiose , Nitrogênio , Bactérias/genética
7.
Acta Radiol ; 64(10): 2802-2811, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37553913

RESUMO

BACKGROUND: Radiomics nomogram analysis is widely preoperatively used to assess gene mutations in various tumors. PURPOSE: To explore the value of computed tomography (CT)-based radiomics nomogram analysis for assessing BRCA gene mutation status of patients with high-grade serous ovarian cancer (HGSOC). MATERIAL AND METHODS: In total, 96 patients with HGSOC were retrospectively screened and randomly divided into primary (n = 68) and validation cohorts (n = 28). The clinical model was constructed based on clinical features and CT morphological features using univariate and multivariate logistic analyses. Maximum-relevance and minimum-redundancy (mRMR) and least absolute shrinkage and selection operator (LASSO) were performed for feature dimensionality reduction and radiomics score was calculated. The nomogram model combining the clinical model and the radiomics score was constructed using multivariate logistic regression. Receiver operating characteristic (ROC) curves were generated to assess models' performance. The calibration analysis and decision curve analysis (DCA) were also performed. RESULTS: The clinical model consisted of CA125 level and supradiaphragmatic lymphadenopathy and yielded an area under the curve (AUC) of 0.69 (primary cohort) and 0.81 (validation cohort). The radiomics model was built with seven selected features and showed an AUC of 0.87 (primary cohort) and 0.81 (validation cohort). The nomogram finally showed the highest AUC of 0.89 (primary cohort) and 0.87 (validation cohort). The nomogram presented favorable calibrations in both the primary and validation cohorts. DCA further confirmed the clinical benefits of the constructed nomogram. CONCLUSION: CT-based radiomics nomogram provides a non-invasive method to discriminate BRCA gene mutation status of HGSOC and potentially helps develop precise medical strategies.

8.
J Environ Manage ; 348: 119358, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37890402

RESUMO

In order to address the problems of poor treatment effect of coal chemical wastewater (CCW) biochemical treatment system resulting in non-compliance with effluent standards and unstable operation, a combination regulation method of co-substrate metabolism and predominant flora enhancement was constructed, and the performance and mechanism of enhanced degradation of aromatics in CCW was also investigated in this study. The results showed that when the influent concentration of chemical oxygen demand (COD) and aromatics was less than 600 mg/L and 180 mg/L respectively, there was no significant effect of the combined regulation method on the enhanced treatment of aromatics, the removal rate of total organic carbon (TOC) in the system could all more than 73%; while when the influent concentration of COD increased to 800 mg/L and the aromatics concentration increased to more than 240 mg/L, the ordinary activated sludge system had collapsed. Compared with the regulation method of co-substrate metabolism alone, the combination regulation method increased the removal rate of TOC by 21%. The analysis of antioxidant enzyme activity showed that under the combination regulation method, the antioxidant enzyme activity of microorganisms was higher and their resistance to adverse environments was stronger. EPS and dehydrogenase analysis indicated that the combination regulation method was more conducive to microbial degradation of aromatics. Meanwhile, the analysis of microbial community structure showed that the aromatics degradation bacteria genera Rhodococcus, Luteococcus, etc. were enriched under the combination regulation method. The study provides a theoretical basis and technical guidance for solving the problems of unstable operation of CCW biochemical treatment systems and non-compliance with effluent standards.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Carvão Mineral , Antioxidantes , Esgotos/química , Reatores Biológicos
9.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555271

RESUMO

Flower development is not only an important way for tomato reproduction but also an important guarantee for tomato fruit production. Although more and more attention has been paid to the study of flower development, there are few studies on the molecular mechanism and gene expression level of tomato flower development. In this study, RNA-seq analysis was performed on two stages of tomato flower development using the Illumina sequencing platform. A total of 8536 DEGs were obtained by sequencing, including 3873 upregulated DEGs and 4663 down-regulated DEGs. These differentially expressed genes are related to plant hormone signaling, starch and sucrose metabolism. The pathways such as pentose, glucuronate interconversion, and Phenylpropanoid biosynthesis are closely related and mainly involved in plant cellular and metabolic processes. According to the enrichment analysis results of DEGs, active energy metabolism can be inferred during flower development, indicating that flower development requires a large amount of energy and material supply. In addition, some plant hormones, such as GA, may also have effects on flower development. Combined with previous studies, the expression levels of Solyc02g087860 and three of bZIPs were significantly increased in the full flowering stage compared with the flower bud stage, indicating that these genes may be closely related to flower development. These genes were previously reported in Arabidopsis but not in tomatoes. Our next work will conduct a detailed functional analysis of the identified bZIP family genes to characterize their association with tomato flower size. This study will provide new genetic resources for flower formation and provide a basis for tomato yield breeding.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Melhoramento Vegetal , Perfilação da Expressão Gênica , Flores/genética , Flores/metabolismo , Genes de Plantas , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Transcriptoma , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
J Xray Sci Technol ; 30(6): 1185-1199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189526

RESUMO

OBJECTIVE: To investigate the value of nomogram analysis based on conventional features and radiomics features of computed tomography (CT) venous phase to differentiate metastatic ovarian tumors (MOTs) from epithelial ovarian tumors (EOTs). METHODS: A dataset involving 286 patients pathologically confirmed with EOTs (training cohort: 133 cases, validation cohort: 68 cases) and MOTs (training cohort: 54 cases, validation cohort: 31 cases) is assembled in this study. Radiomics features are extracted from the venous phase of CT images. Logistic regression is employed to build models based on conventional features (model 1), radiomics features (model 2), and the combination of model 1 and model 2 (model 3). Diagnostic performance is assessed and compared. Additionally, a nomogram is plotted for model 3, and decision curve analysis is applied for clinical use. RESULTS: Age, abdominal metastasis, para-aortic lymph node metastasis, location, and septation are chosen to build Model 1. Ten optimal radiomics features are ultimately selected and radiomics score (rad-score) is calculated to build Model 2. Nomogram score is calculated to build model 3 that shows optimal diagnostic performance in both the training (AUC = 0.952) and validation cohorts (AUC = 0.720), followed by model 1 (AUC = 0.872 for training cohort and AUC = 0.709 for validation cohort) and model 2 (AUC = 0.833 for training cohort and AUC = 0.620 for validation cohort). Additionally, Model 3 achieves accuracy, sensitivity, and specificity of 0.893, 0.880, and 0.926 in the training cohort and 0.737, 0.853, and 0.613 in the validation cohort. CONCLUSION: Model 3 demonstrates the best diagnostic performance for preoperative differentiation of MOTs from EOTs. Thus, nomogram analysis based on Model 3 may be used as a biomarker to differentiate MOTs from EOTs.


Assuntos
Nomogramas , Neoplasias Ovarianas , Feminino , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Metástase Linfática , Neoplasias Ovarianas/diagnóstico por imagem
11.
Ecotoxicol Environ Saf ; 225: 112789, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560613

RESUMO

A slow degradation rate and low transformation efficiency are the main problems in the biodegradation of polycyclic aromatic hydrocarbons (PAHs). This study selected pyrene as the target PAH to investigate the effect of ferrous ion and ferric ion on pyrene degradation. The driving effect and mechanism, including the interaction between pyrene and iron ions and the bacterial physiological response during the biodegradation process by Rhodococcus ruber strain L9, were investigated. The results showed that iron ions did not enhance bacterial growth but improved bacteria's pyrene removal capacity, contributing to the total efficiency of pyrene biodegradation. The process started with an initial formation of "cation-π" between Fe (III) and pyrene, which subsequently drove the pyrene removal process and accelerated the bacterial metabolic process. Moreover, a significant increase in the protein concentration, catechol dioxygenase (C12O and C23O) activities, and intracellular protein regulation in crude enzyme solution indicate a positive response of the bacteria during the iron ion-enhanced pyrene degradation process.


Assuntos
Ferro , Rhodococcus , Íons , Pirenos
12.
Acta Radiol ; 61(6): 848-855, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31615267

RESUMO

BACKGROUND: Lymph nodes metastasis is an important factor affecting survival rate and recurrence in cervical cancer patients. Currently, diagnosis of metastatic lymph nodes is mainly based on morphological changes on imaging. However, it is difficult to differentiate normal-sized metastatic lymph nodes with short axis of 5-10mm. PURPOSE: To assess the diagnostic value of apparent diffusion coefficient (ADC) for discriminating different-sized metastatic lymph nodes in patients with cervical cancers. MATERIAL AND METHODS: Pathologically confirmed cervical cancer patients were documented from January 2013 to July 2018 in our hospital. A total of 133 patients who underwent conventional MRI and diffusion-weighted imaging with complete pathology were finally enrolled. A total of 157 lymph nodes were harvested and analyzed. All lymph nodes were divided into three groups according to pathology and their short axis (S) measured on axial T2-weighted imaging: normal-sized (5 mm

Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Metástase Linfática/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Radiol Med ; 125(12): 1233-1242, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32424659

RESUMO

PURPOSE: To explore the value of histogram analysis of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) quantitative parameters and apparent diffusion coefficient (ADC) values in predicting the neoadjuvant chemotherapy (NACT) response for cervical cancers. METHODS: Sixty-three patients with pathologically proved stage IB2-IIA2 cervical cancer from March 2013 to January 2017 were retrospectively analyzed. They were divided into two groups on the basis of therapeutic response: the significant response (SR) group, which contains complete response patients and partial response patients, and nonsignificant response (non-SR) group, which contains progressive diseases and stable diseases. Clinical characteristics, DCE-MRI parameters (Ktrans, Kep, Ve), and ADC values before NACT were analyzed and compared between the two groups. RESULTS: SR group and non-SR group were documented in 35 and 28 patients. The mean Ktrans value, 90th percentile Ktrans value, maximal Ktrans value, and 90th percentile ADC value of tumors in SR were significantly higher than those in non-SR group (P = 0.012, P = 0.022, P = 0.005, P = 0.033, respectively), and the mean Ve value and 10th percentile Ve value of tumors were significantly lower in SR group (P = 0.041, P = 0.033, respectively). Kep values did not significantly differ between SR and non-SR. The 90th percentile Ktrans value combined with the 90th percentile ADC value had the highest area under the curve at 0.740 (P = 0.003) to predict NACT effectiveness. CONCLUSION: Histogram analysis of DCE-MRI multi-parameters combined with ADC values may serve as sensitive indicators for predicting NACT effectiveness in cervical cancers.


Assuntos
Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/tratamento farmacológico , Quimioterapia Adjuvante , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia
14.
Environ Geochem Health ; 41(2): 617-632, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30027363

RESUMO

The Yulin National Energy and Chemical Industry Base is widely known for its rich mineral resources and multi-type fossil chemical industry, yet little is known regarding the level of contaminants. Therefore, this study investigates the spatial distributions and potential exposure risk of ubiquitous polycyclic aromatic hydrocarbons (PAHs) contamination in this region and apportions PAHs source and source-oriented risk using two mathematical models, principal component analysis-multiple linear regression (PCA-MLR) model and positive matrix factorization (PMF) model coupling human health exposure risk. Results showed that ∑16PAHs concentrations ranged from 110 to 4934 µg/kg dw in 38 soil sampling sites. Compared with PCA-MLR model, PMF model is preferred method for source apportionment. Source apportionment results derived from PMF model indicated that the dominant contribution to ∑16PAHs was from coal-derived sources (34% for coke oven emissions and 33% coal combustion source), followed by wood combustion (22%) and vehicular emission (11%). The human health exposure risk of each source category was quantitatively calculated for three exposure routes by combining the total carcinogenic risk (Total-CR) and total hazard index (Total-HI) values with identified source contributions. The results showed that increased Total-CR was highly apportioned from coke oven emissions source and coal combustion was identified as the major cause of increased Total-HI, even though it was less contributed to ∑16PAHs. Moreover, the distributions of Total-CR and Total-HI apportionment for each source were significantly influenced by land utilization types.


Assuntos
Exposição Ambiental/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco/métodos , Poluentes do Solo/análise , Indústria Química , China , Carvão Mineral , Monitoramento Ambiental/métodos , Humanos , Modelos Lineares , Modelos Teóricos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Análise de Componente Principal , Poluentes do Solo/toxicidade , Emissões de Veículos
15.
Environ Monit Assess ; 191(5): 293, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31016390

RESUMO

The Yulin Energy and Chemical Industry Base is widely known for its rich mineral resources and multiple types of fossil-fuel-based chemical industries; nevertheless, information regarding the level of toxic contaminants in the surface waters is lacking in this area. Therefore, this study investigates the distributions, sources, and risks of various toxic contaminants, including heavy metals, organochlorine pesticides (OCPs), and polycyclic aromatic hydrocarbons (PAHs), from 35 sampling sites in eight rivers. The ΣHCH concentration ranged from 1.28 to 6.64 ng/L with predominant ß-HCH, and the ΣDDT concentration was less than 0.35 ng/L. The OCPs were derived from the recent input of lindane, residual technical-grade HCHs, and DDTs. The soil type can affect the environmental fate of DDT, and p,p'-DDE was widespread in the sandy land and loess areas. p,p'-DDD was rarely detected in the Mu Us Sandy Land area. The calculated ratios of isomers indicated that petroleum was the major source of PAHs. OCP and PAH contamination in the surface waters posed potential risks at several sampling sites. Due to the impacts by industrial emissions, agricultural sources, and vehicular traffic, the distribution of contaminant concentrations in the surface waters exhibited a significant spatial relationship with the land use pattern in the study region according to the results of principal component analysis and cluster analysis.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , China , Medição de Risco
16.
Sensors (Basel) ; 16(11)2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27792152

RESUMO

Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS) datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS). It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2-3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests' features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

17.
ACS Appl Mater Interfaces ; 16(3): 3564-3575, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38206319

RESUMO

The nitrogen oxidation reaction (NOR) to form nitric acid by applying natural air and H2O under ambient conditions is a sustainable approach to achieving efficient and selective N2 fixation for industrial applications. In this study, four kinds of Co3O4 catalysts with a controllable microstructure were prepared to catalyze the direct NOR of N2 in the air. At the same time, the reaction mechanism of the conversion of N2 to nitric acid under catalytic ozonation was explored through experimental research and density functional theory (DFT) calculation. The results showed that the prepared porous nanosheets self-assembled into microflower-structured samples. The HCOF showed extraordinary catalytic performance for direct NOR to produce a high concentration of nitric acid. The maximum rate of nitric acid formation could be as high as 6.67 mmol/(h·gcat), which was higher than those of most reported photocatalytic or electrocatalytic N2 fixation processes for direct NOR to produce NO3-. Furthermore, the 15N isotopic-labeling experiment confirmed that the produced NO3- originated from N2 in the air by the direct NOR process. In the direct NOR mechanism, inert N2 molecules were captured at the Co3+ active sites by the acceptance-donation electron conduction mode, and the oxygen vacancies boosted the chemical adsorption of N2 molecules and greatly reduced the activation energy barrier of N2 molecules. The active free radicals •OH and •O2- generated by the decomposition of O3 molecules oxidized N2 to the intermediate *NO, which was the rate-determining step, and it was then absorbed by water to form nitric acid. The air catalytic ozonation method in this study was proposed as a facile pathway for efficient nitrogen fixation. This research provides a new method for environmental protection and efficient production of nitric acid at distributed sources.

18.
Chemosphere ; 349: 140943, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096992

RESUMO

In response to the problem of high emulsified and dissolved oils being difficult to recovery from coal chemical wastewater (CCW), this study specifically constructed a non-polar, macropore, and hydrophobic adsorption material (pSt-X) based on the main components of these two oils (aromatics and phenols) for selective recovery. The results revealed that pSt-X had an adsorption capacity of 215.52 mg/g, which had remained stable for multiple recycling sessions, with an adsorption capacity constantly above 95 %. The pSt-X has significantly larger particle size (0.7 mm-1.2 mm), which simplifies the process of adsorption regeneration and effectively prevents the loss of the adsorbent powder problem. The pSt-X adsorbent demonstrated remarkable selectivity towards dissolved and emulsified oils, exhibiting removal rates of 90.2 % and 81.7 %, respectively. Moreover, pSt-X proved remarkable selectivity in removing aromatic hydrocarbons (AHs) and phenols, with impressive removal rates of 77.8 % and 85.9 %, respectively. The selective separation mechanism of pSt-X for oil substances was further analyzed, indicating that its selective adsorption of oils was primarily driven by hydrophobic, π-π, and hydrogen bonding interactions owing to its non-polar and macropore structure and hydrophobic properties. The results of this study provide solid theoretical support for green and low-carbon recovery of oil substances in CCW and are of positive practical importance for clean production in the coal chemical industry.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Carvão Mineral , Adsorção , Óleos , Fenóis , Poluentes Químicos da Água/química
19.
Eur J Radiol ; 178: 111622, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39018648

RESUMO

PURPOSE: To investigate the value of microstructural characteristics derived from time-dependent diffusion MRI in distinguishing high-grade serous ovarian cancer (HGSOC) from serous borderline ovarian tumor (SBOT) and the associations of immunohistochemical markers with microstructural features. METHODS: Totally 34 HGSOC and 12 SBOT cases who received preoperative pelvic MRI were retrospectively included in this study. Two radiologists delineated the tumors to obtain the regions of interest (ROIs). Time-dependent diffusion MRI signals were fitted by the IMPULSED (imaging microstructural parameters using limited spectrally edited diffusion) model, to extract microstructural parameters, including fraction of the intracellular component (fin), cell diameter (d), cellularity and extracellular diffusivity (Dex). Apparent diffusion coefficient (ADC) values were obtained from standard diffusion-weighted imaging (DWI). The parameters of HGSOCs and SBOTs were compared, and the diagnostic performance was evaluated. The associations of microstructural indexes with immunopathological parameters were assessed, including Ki-67, P53, Pax-8, ER and PR. RESULTS: In this study, fin, cellularity, Dex and ADC had good diagnostic performance levels in differentiating HGSOC from SBOT, with AUCs of 0.936, 0.909, 0.902 and 0.914, respectively. There were no significant differences in diagnostic performance among these parameters. Spearman analysis revealed in the HGSOC group, cellularity had a significant positive correlation with P53 expression (P = 0.028, r = 0.389) and Dex had a significant positive correlation with Pax-8 expression (P = 0.018, r = 0.415). ICC showed excellent agreement for all parameters. CONCLUSION: Time-dependent diffusion MRI had value in evaluating the microstructures of HGSOC and SBOT and could discriminate between these tumors.

20.
ACS Appl Mater Interfaces ; 16(15): 19519-19528, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38580622

RESUMO

The inherent flammability of most polymeric materials poses a significant fire hazard, leading to substantial property damage and loss of life. A universal flame-retardant protective coating is considered as a promising strategy to mitigate such risks; however, simultaneously achieving high transparency of the coatings remains a great challenge. Here, inspired by the moth eye effect, we designed a nanoporous structure into a protective coating that leverages a hydrophilic-hydrophobic interactive assembly facilitated by phosphoric acid protonated amino siloxane. The coating demonstrates robust adhesion to a diverse range of substrates, including but not limited to fabrics, foams, paper, and wood. As expected, its moth-eye-inspired nanoporous structure conferred a high visible light transparency of >97% and water vapor transmittance of 96%. The synergistic effect among phosphorus (P), nitrogen (N), and silicon (Si) largely enhanced the char-forming ability and restricted the decomposition of the coated substrates, which successfully endowed the coating with high fire-fighting performance. More importantly, for both flexible and rigid substrates, the coated samples all possessed great mechanical properties. This work provides a new insight for the design of protective coatings, particularly focusing on achieving high transparency.

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