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1.
Huan Jing Ke Xue ; 45(2): 678-688, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471908

RESUMO

Based on the one-year observational data of volatile organic compounds (VOCs) in an urban area of Yuncheng in 2021, the concentration, composition, sources, and ozone-sensitive species of VOCs in four seasons were analyzed. The results showed that the average annual concentration of VOCs was (32.1 ±24.2)×10-9, i.e., at the national middle level. The seasonal concentrations of VOCs were in the order of: winter (46.3×10-9)> autumn (35.5×10-9)> spring (25.6×10-9)> summer (21.2×10-9). Alkanes and OVOCs were the most dominant VOCs compounds, accounting for 69.0%-80.4% of TVOCs in Yuncheng. Affected by changes in source emissions, the proportion of OVOCs was higher in spring and summer (41%-43%), whereas the proportion of alkanes was higher in autumn and winter (42%-43%). Vehicle exhaust, LPG/NG, industrial production, and combustion sources were identified as the main sources of VOCs in Yuncheng. The largest contributors in the four seasons were vehicle exhaust (28.5% in spring), secondary + combustion sources (29.0% in summer), LPG/NG sources (30.4% in autumn), and coal combustion (27.3% in winter). The ozone formation was located in the transitional regime in summer and in the VOC-limited regime in other seasons. Ozone production was more sensitive to alkenes (isoprene, ethylene, and propene), OVOCs (acetaldehyde and propanal), and aromatics (xylene, toluene, and benzene). Winter was more sensitive to ethylene, and the other seasons were more sensitive to isoprene. The primary emission sources related to these sensitive species should be reduced to achieve the goal of air quality improvement.

2.
Front Plant Sci ; 14: 1239237, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719207

RESUMO

Empoasca onukii is a major pest that attacks tea plants. To seek effective and sustainable methods to control the pest, it is necessary to assess its host preference among different species of tea and understand the critical factors behind this behavior. In this study, the behavioral preference of E. onukii for volatile organic compounds (VOCs) of three potted tea species was evaluated. The VOCs released by the three tea species were analyzed using gas chromatography-mass spectrometry, and the major components were used to test the pest's preference. Transcriptome analysis was used to infer the key genes that affect the biosyntheses of the VOCs. The results showed that the tendency of E. onukii toward the VOCs of the three tea species was the strongest in green tea, followed by white tea, and the weakest in red tea. This behavioral preference was significantly and positively correlated with the relative levels of hexanol, linalool, and geraniol in tea volatiles. Relative hexanol was significantly and positively correlated with the expression of genes TEA009423 (LOX2.1), TEA009596 (LOX1.5), TEA008699 (HPL), TEA018669 (CYPADH), and TEA015686 (ADHIII). Relative linalool was significantly and positively correlated with the expression of genes TEA001435 (CAD) and Camellia_sinensis_newGene_22126 (TPS). Relative geraniol was significantly and positively correlated with the expression of genes TEA001435 (CAD), TEA002658 (CYP76B6), TEA025455 (CYP76T24), and Camellia_sinensis_newGene_22126 (TPS). The above findings suggested that three volatiles (hexanol, linalool, and geraniol) determined the behavioral preference of E. onukii toward tea plants, and their biosynthesis was mainly affected by nine genes (TEA009423, TEA009596, TEA008699, TEA018669, TEA015686, TEA001435, TEA002658, TEA025455, and Camellia_sinensis_newGene_22126).

3.
Sci Total Environ ; 892: 164418, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37257596

RESUMO

Phytoremediation provides substantial advantages, including eco-friendliness, cost-effectiveness, efficiency, and visual appeal. However, the current knowledge of the factors influencing phytoremediation in pesticide-contaminated environments remains limited. It is critical to understand phytoremediation and the factors affecting the variation in removal efficiency. In this study, we compiled 72 previous research articles to quantify plant-induced improvements in removal efficiency and identify factors that influence variations in phytoremediation behavior through meta-analysis. We observed a significant increase in the removal efficiency of phytoremediation compared to the control group which did not involve phytoremediation. Pesticides significantly affect removal efficiency in terms of their modes of action, substance group, and properties. Plants demonstrated higher efficiency in remediating environments contaminated with pesticides possessing lower molecular masses and log Kow values. Plant species emerged as a crucial determinant of variations in removal efficiency. Annual plants exhibited a 1.45-fold higher removal efficiency than perennial plants. The removal efficiencies of different plant types decreased in the following order: agri-food crops > aquatic macrophytes > turfgrasses > medicinal plants > forage crops > woody trees. The Gramineae family, which was the most prevalent, demonstrated a robust and consistent phytoremediation ability. This study offers a more comprehensive triangular relationship between removal efficiency, pesticides, and plants, expanding the traditional linear model. Our findings offer valuable insights into the behavior of phytoremediation in pesticide-contaminated environments and the factors determining its success, ultimately guiding further research toward developing strategies for higher removal efficiency in phytoremediation.


Assuntos
Praguicidas , Poluentes do Solo , Biodegradação Ambiental , Poaceae , Produtos Agrícolas , Árvores
4.
Huan Jing Ke Xue ; 43(6): 2979-2986, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686767

RESUMO

Based on the online monitoring data of VOCs, O3, and NO2 in Yuncheng City from June to August 2020, the pollution characteristics of VOCs in Yuncheng City in summer were analyzed. At the same time, the main emission sources were determined using a PMF model, and the chemical reactivity of VOCs was evaluated using the maximum incremental reactivity (MIR) method and fractional aerosol coefficients (FAC). The results showed that the urban area of Yuncheng was seriously polluted by VOCs and NO2 in the early morning and evening during summer, the peak value of VOCs daily variation occurred at 08:00 and 20:00, respectively, and was mainly affected by the morning and evening peaks in traffic. The ρ(VOCs) from June to August was 50.52 µg·m-3, and the species with the highest proportion were alkanes (39.39%) and oxygenated volatile organic compounds (OVOCs, 34.63%). Five VOCs emission sources were determined by the PMF model, of which the largest contribution was from motor vehicle exhaust emission sources (33.10%), followed by industrial emission sources (29.46%), natural gas and coal combustion sources (17.31%), solvent use sources (11.94%), and plant emission sources (8.19%). Controlling motor vehicle exhaust emission sources is the key to alleviate VOCs pollution in summer in Yuncheng City. The average ozone formation potential (OFP) of VOCs was 162.88 µg·m-3, in which OVOCs had the highest contribution rate (45.37%); acetaldehyde, propionaldehyde, ethylene, isoprene, and toluene were the key active components; and industrial emission sources were the emission sources with the highest contribution rate. The average value of secondary organic aerosol formation potential (SOAp) of VOCs was 0.40 µg·m-3, in which the contribution rate of aromatic hydrocarbons was the highest (88.00%), and the solvent use source was the emission source with the highest contribution rate.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio , Ozônio/análise , Solventes , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
5.
Huan Jing Ke Xue ; 42(4): 1626-1635, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742797

RESUMO

In order to reveal the chemical composition characteristics and pollution sources of fine particulate matter (PM2.5) in autumn and winter in Yuncheng, PM2.5 samples were continuously collected using a four-channel small-flow particulate sampler from October 15, 2018 to March 15, 2019. The study prediminantly analyzed the chemical components of water-soluble ions, elemental carbon, organic carbon, and metal elements. Additionally, the chemical mass reconstruction method of particulate matter and the positive matrix factorization model (PMF) were combined for an in-depth discussion. During the sample period, the PM2.5 mass concentrations range was 29.37-370.11 µg·m-3, and 101 days during the sampling period exhibited concentrations that were higher than the secondary standard in China's Ambient Air Quality Standards (GB 3095-2012), with an exceeding rate of 70.63%. These results indicate that the air pollution in Yuncheng in autumn and winter is serious. According to the air quality index (AQI), the collected samples are classified as clean, light-moderate pollution, and heavy-severe pollution. Water-soluble ions, OC, EC and metal elements account for 40%, 19%, 5%, and 7% on clean days, 46%, 18%, 4%, and 5% on days with light-moderate pollution, and 46%, 21%, 4%, and 4% on days with heavy-severe pollution, respectively. Secondary ions NO3-, SO42-, and NH4+ are the primary components of water-soluble ions, accounting for 81% (clean days), 87% (light-moderate pollution), and 87% (heavy-severe pollution) of the total ion concentration, respectively. The OC/EC ratios during the sampling period were 3.78 (clean days), 4.02 (light-moderate pollution), and 5.37 (heavy-severe pollution). With the intensification of pollution, the pollution of secondary organic aerosols in the atmosphere becomes increasingly serious. In addition, as the air pollution increased, the concentration of Fe and Cr elements gradually decreased, while the concentration of other metal elements showed an overall upward trend. The results of the chemical mass reconstruction demonstrate that among the different pollution levels of atmospheric PM2.5 in Yuncheng, the mass percentages of secondary inorganic salt, sea salt, heavy metals, mineral dust, construction dust, organic matter, and elemental carbon were 36%, 2%, 2%, 8%, 1%, 33%, and 5% (clean days), 41%, 1%, 1%, 5%, 0.01%, 31%, and 5% (light-moderate pollution), and 41%, 1%, 1%, 4%, 0.004%, 34%, and 4% (heavy-severe pollution). The proportion of secondary inorganic ions increased and mineral dust decreased with the deterioration of air quality. The PMF analysis results suggest that secondary related sources, coal combustion sources, vehicle exhaust sources, biomass burning, and secondary organic matter are the predominant sources of PM2.5 during serious air pollution in Yuncheng.

6.
Ecotoxicol Environ Saf ; 148: 169-176, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29054028

RESUMO

Fomesafen, a widely adopted residual herbicide, is used throughout the soybean region of northern China for the spring planting. However, the ecological risks of using fomesafen in soil remain unknown. The aim of this work was to evaluate the impact of fomesafen on the microbial community structure of soil using laboratory and field experiments. Under laboratory conditions, the application of fomesafen at concentrations of 3.75 and 37.5mg/kg decreased the basal respiration (RB) and microbial biomass carbon (MBC). In contrast, treatment with 375mg/kg of fomesafen resulted in a significant decrease in the RB, MBC, abundance of both Gram+ and Gram- bacteria, and fungal biomass. Analysis of variance showed that the treatment accounted for most of the variance (38.3%) observed in the soil microbial communities. Furthermore, the field experiment showed that long-term fomesafen application in continuously cropped soybean fields affected the soil bacterial community composition by increasing the relative average abundance of Proteobacteria and Actinobacteria species and decreasing the abundance of Verrucomicrobia species. In addition, Acidobacteria and Chloroflexi species showed a pattern of activation-inhibition. Taken together, our results suggest that the application of fomesafen can affect the community structure of soil bacteria in the spring planting soybean region of northern China.


Assuntos
Benzamidas/toxicidade , Glycine max/crescimento & desenvolvimento , Herbicidas/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Solo/química , Actinobacteria/efeitos dos fármacos , Benzamidas/análise , Biomassa , China , Fungos/efeitos dos fármacos , Herbicidas/análise , Proteobactérias/efeitos dos fármacos , Poluentes do Solo/análise
7.
J Alzheimers Dis ; 51(1): 45-55, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26836015

RESUMO

Abnormal cholesterol metabolism is an established feature of Alzheimer's disease (AD). Cerebrospinal fluid (CSF) is the fluid surrounding the central nervous system, and the protein and lipid content alterations in the CSF could be biomarkers for degenerative changes in the brain. The laboratory diagnosis of AD is limited to the analysis of three biomarkers in CSF: Aß42, total tau, and phospho-tau. The purpose of this analysis is to systematically analyze the available data describing the biomarkers of cholesterol and its metabolites in the CSF of subjects with AD. MEDLINE, EMBASE, and the Cochrane Central database were systematically queried to collect studies that have evaluated the markers of cholesterol and its metabolites in the CSF of subjects with mild cognitive impairment (MCI) or AD and age-matched controls. Analysis of the published data shows that the levels of cholesterol are increased in MCI subjects; 24-hydroxycholesterol and 27-hydroxycholesterol are elevated in AD and MCI subjects compared to controls. There is a significant dysfunction of cholesterol metabolism in the CSF of AD subjects. This analysis indicates that in addition to the available biomarkers in the CSF, such as Aß42, total tau, and phospho-tau, 24-hydroxycholesterol, 27-hydroxycholesterol, and cholesterol appear to be sensitive biomarkers for the evaluation of MCI and AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Colesterol/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Hidroxicolesteróis/líquido cefalorraquidiano , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos
8.
Exp Ther Med ; 8(6): 1745-1750, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25371726

RESUMO

Nasopharyngeal carcinoma (NPC) is a malignancy with a high metastatic ability. Recent studies have implicated the role of chromodomain helicase/ATPase DNA binding protein 1-like (CHD1L) gene as a novel oncogene; however, the functional role of CHD1L in NPC remains unknown. The aim of this study was to evaluate the clinical significance of CHD1L positivity in NPC. CHD1L protein expression was examined by performing western blot analysis of 30 fresh NPC tissues and conducting immunohistochemistry tests of 133 NPC samples between December 1, 2005 and December 1, 2009. The correlations of CHD1L expression status with clinicopathological features and prognosis were investigated. Immunohistochemical analysis showed that 88 of 133 (66.2%) paraffin-embedded NPC biopsies exhibited positive expression of CHD1L, but all non-cancerous nasopharyngeal specimens were negative for CHD1L expression. In addition, positive CHD1L expression was strongly associated with an advanced clinical stage (P=0.016), recurrence (P=0.002) and the metastasis status (P=0.031) of NPC. Kaplan-Meier survival analysis demonstrated that patients with CHD1L-positive NPC had significantly shorter overall survival (P<0.001). Furthermore, the multivariate analysis indicated that CHD1L protein expression was an independent prognostic factor for overall survival (hazard ratio, 7.916; 95% confidence interval, 2.067-16.034; P=0.003) in patients with NPC. These results indicate that CHD1L is a prognostic marker for NPC.

10.
Ying Yong Sheng Tai Xue Bao ; 21(11): 2992-6, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21361029

RESUMO

By using phospholipid fatty acids (PLFA) method, this paper studied the soil microbial community structure in the soybean fields with different chlorimuron-ethyl application history in Weihe district of Heilongjiang Province. In the meantime, the residual amount of chlorimuron-ethyl in soil was determined. There was a very low residual of chlorimuron-ethyl in soil under the conditions of different chlorimuron-ethyl application history. With the increasing year of chlorimuron-ethyl application, the total concentration of soil microbial PLFA and the ratios of fungi/bacteria and Gram negative/Gram positive bacteria decreased, and the microbial stress level increased. Principal component analysis (PCA) showed that long-term application of chlorimuron-ethyl into soybean field changed the soil microbial community structure significantly.


Assuntos
Ecossistema , Glycine max/crescimento & desenvolvimento , Pirimidinas/farmacologia , Microbiologia do Solo , Compostos de Sulfonilureia/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , China , Monitoramento Ambiental , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Herbicidas/análise , Herbicidas/farmacologia , Dinâmica Populacional , Análise de Componente Principal , Pirimidinas/análise , Compostos de Sulfonilureia/análise
11.
J AOAC Int ; 92(3): 919-26, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19610386

RESUMO

In this paper, a simple, and rapid analysis of bromoxynil octanoate is reported for soil, corn leaves, and corn seeds by utilizing one-step liquid-liquid extraction and partitioning, followed by GC with electron capture (ECD) and mass spectrometry (MS) detection. The method was validated by recovery experiments and assessment of matrix effects. Recoveries for GC-ECD and GC/MS were 82.3-110.7% with a relative standard deviation of <14% using matrix-matched calibration solutions for quantification. The limit of quantitation (LOQ) values were 0.005 and 0.2 mg/kg for the ECD and MS detector, respectively, depending on the sensitivity of the target compound. The concentration levels for bromoxynil octanoate residue found in soil, corn leaves, and corn seeds from field experiments were clearly below the LOQ of the ECD detector. The half-life times of bromoxynil octanoate were 2.2-4.2 days in soil and corn leaves. These results indicated that the developed method was appropriate for analysis of bromoxynil octanoate in soil and corn samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Herbicidas/análise , Nitrilas/análise , Poluentes do Solo/análise , Zea mays/química
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(1): 250-5, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19385251

RESUMO

The inorganic particles hybrid polyimide films are newly emerging advanced materials with excellent corona-resistant and have been widely used in frequency control motor. The Al2O3/PI hybrid films with different Al2O3 contents were prepared by superfine aluminum power treated by coupling agent and polyamide acid (PAA). Qualitative analysis and quantitative analysis on the inorganic content to it were conducted using Fourier Transform Infrared Spectroscope (FTIR), X-ray photoelectron spectroscopy (XPS), Inductively coupled plasma spectrometry (ICP), Gravimetric method, Thermogravimetric Analysis (TG/air atmosphere). It was found that FTIR and XPS are good qualitative analysis methods. FTIR is used to inference possible components by analyzing the structure of material. The method has a lot of advantages such as easily operational, good repeatability, high accuracy and so on. XPS is mainly used to get information of elements contained in the material, it provides information about the core level binding energies and oxidation states of complexes. It can be used to identify the species and valence states of elements, measure the relative content of elements. The relative standard deviations (RSDs) of XPS and TG are too great to perform quantitative analysis, the RSDs of XPS are all above 5.0%, and TG's RSDs are also above 2.0%. So they can be only used as semiquantitative analysis methods. On the contrary, ICP and Gravimetric method are two excellent quantitative analysis methods, their RSDs are all below 1.0%. Moreover Gravimetric method only can be used to analyze single inorganic constituent complex material, although its measured value is closest approach to theoretical value. ICP is the most accurate method and it can be used to analyze multi inorganic components in complex material, this method proved to be easily operational, rapid, highly sensitive, and accurate, and can be adopted as the method of determining many elements simultaneously. So a method was got to analysis of inorganic constituent in complex material from the conclusion upward. Firstly, components in complex material are defined by using FTIR and XPS as qualitative analysis methods and then using the result of XPS as a reference, exactly quantitative analysis of inorganic constituent in complex material was performed by using Gravimetric method and ICP.

13.
J AOAC Int ; 91(5): 1110-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18980126

RESUMO

A liquid chromatographic/mass spectrometric (LC/MS) method is reported for the determination of the onium-type plant growth regulator mepiquat chloride in cotton and soil. The pesticide was extracted from the sample with ethanol and water containing 2% NH4Cl. The extract was cleaned up on a solid-phase extraction C18 column, and the pesticide was determined by LC/MS. The average recoveries were 85.9-93.8, 81.3-91.7, and 78.1-94.7%, with corresponding relative standard deviations of 3.4-9.6, 3.7-12.3, and 4.0-9.8%, from soil, cotton leaves, and cotton seeds, respectively. A coefficient of determination of R2 = 0.9964 was obtained for the analyte calibration graph, from 0.05 to 100 microg/mL. Decision limits, CCalpha, and detection capability, CCbeta, were calculated. Electrospray ionization LC/MS in the positive-ion mode (ESI+) was used to detect mepiquat chloride in extracts of soil, cotton leaves, and cotton seeds. The ion at m/z 114 in the mass spectrum was monitored.


Assuntos
Gossypium/química , Piperidinas/análise , Reguladores de Crescimento de Plantas/análise , Solo/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Indicadores e Reagentes , Espectrometria de Massas , Resíduos de Praguicidas/análise , Folhas de Planta/química , Padrões de Referência , Sementes/química , Soluções
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(3): 707-10, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18536449

RESUMO

The key to the study on the regularity about the mechanical, thermology and electricities property of the inorganic nano-mingled organic composition thin film is to understand the incorporated quantity, the particle size and distribution of nano-inorganic matter in the membrane quickly and accurately. In the present paper, the chemical structure, surface morphology and the actual content of nano-Al2O3 of the nano Al2O3-composite film of polyimide were characterized by X-ray atomic fluorescent spectroscopy (XRF), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and atomic forced microscope (AFM). The results are that the organic phase of PI and the inorganic phase of Al2O3 formed a complex composite hybrid system of bond-to-bond pattern, the nano-Al2O3 particles in the film of PI are dispersed homogeneously, and the diameter of the particle is smaller than 50 nm; the weight content of Al2O3 is 7.9% by XRF. The approach we used is an effective way of analyzing the inorganic component of the organic composite film materials doped with the inorganic nano-phase materials with the merits of no pretreatment, no fed charge (for analysis of insulation materials), no-contagion, no destruction, high speed and high accuracy, etc.

15.
Nan Fang Yi Ke Da Xue Xue Bao ; 26(5): 587-90, 593, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16762856

RESUMO

We present a new mixing rigid-elastic multiresolution algorithm for medical image registration from global registration to local registration in sequence. The global registration is achieved by the method of affine transformation composed of B spline, which knots are the four vertexes of the medical image. When increasing the number of the knots of the B spline along the X and Y axis, the transformation function will be more complex and "elastic", which can complete the elastic aligning for the detail of the medical image. The results of experiment demonstrated that the presented algorithm was more robust than the previous elastic algorithm of registration.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Animais , Elasticidade , Humanos , Imageamento por Ressonância Magnética/métodos , Modelos Teóricos , Tomografia Computadorizada por Raios X
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