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1.
Mol Biotechnol ; 66(2): 300-310, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37118319

RESUMO

Tumor microenvironment has significant influence on the gene expression of tumor tissues and on the clinical outcomes in lung adenocarcinoma. Infiltrating immune and stromal cells not only perturb the tumor signal in molecular studies, but also play crucial roles in cancer biology. The competing endogenous RNAs (ceRNAs) are useful to explain the post-transcriptional layer regulated by gene translation and play an important role in the occurrence and progression of lung adenocarcinoma. Therefore, identifying novel molecular markers by constructing ceRNA associated with immune infiltration is of great significance to guide the treatment of lung adenocarcinoma in the future. According to the immune and stromal scores of lung adenocarcinoma samples in The Cancer Genome Atlas (TCGA) database calculated by the ESTIMATE algorithm, we identified differentially expressed lncRNAs, miRNAs and mRNAs associated with immune infiltration, including 60 dysregulated lncRNAs, 38 dysregulated mRNAs, and 29 dysregulated miRNAs. Based on the PPI network and Cox regression analysis, 5 mRNAs including CNR2, P2RY12, ZNF831, RSPO1, and F2 were identified to be related to immune infiltration and prognosis in lung adenocarcinoma, and their differential expression, prognosis and correlation with immune cells were verified. Next, through target binding prediction, pearson correlation analysis and expression analysis, a novel immune-related ceRNA network containing 6 lncRNAs, 4 miRNAs, and 3 mRNAs was finally constructed. The present study constructed a novel immune-associated lncRNA-miRNA-mRNA ceRNA network, which deepens our understanding on the molecular network mechanism of lung adenocarcinoma and provides potential prognostic markers and novel therapeutic targets for the patients with lung adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Endógeno Competitivo , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Redes Reguladoras de Genes , Biomarcadores Tumorais/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adenocarcinoma/genética , Pulmão/patologia , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral/genética
2.
PLoS One ; 18(9): e0291115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37708172

RESUMO

Bench blasting is the primary means of production in open-pit metal mines. The size of the resulting rock mass after blasting has a significant impact on production cost. Currently, the ore fragment size is obtained mainly through manual measurement or estimation with the naked eye, which is inefficient and inaccurate. This study proposes the U-CARFnet and U-Net models for segmenting blasting fragment images from open-pit mines based on an attention mechanism, residual learning module, and focal loss function. It compares this technique with traditional image segmentation ones and a variety of deep learning models to verify the efficacy of the proposed model. Experimental results show that the accuracy of the U-CARFnet model proposed in this paper reaches 97.11% in the performance evaluation, which shows better performance than the traditional image segmentation method. In this study, the U-CARFnet model is used in the application, and a superior performance is obtained, with an average segmentation error of 5.46%. The proposed approach provides an effective technique for statistically analyzing images of mine rock.

3.
Eur J Clin Microbiol Infect Dis ; 42(10): 1195-1205, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604947

RESUMO

PURPOSE: Highly active antiretroviral therapy (HAART) is an accepted treatment option for patients with virus infection. Mounting evidence indicated that persistent HAART treatment is implicated with increased morbidity of HIV-associated neurocognitive disorders (HAND) in patients. Tenofovir disoproxil fumarate (TDF), a novel nucleotide reverse transcriptase inhibitor (NRTI), was used in patients with HIV co-infected with HBV. And it is still a vital first-line antiretroviral compounds in HAART. However, whether persistent treatment with TDF is involved in HAND development remains to be further elucidated. In this study, we aimed to discuss the neurotoxicity of TDF. METHODS: We used SH-SY5Y cells and primary neuronal cells to evaluate the neurotoxicity of TDF in vitro. The cytotoxicity of TDF on SH-SY5Y cells and primary neuronal cells was evaluated by the cell viability and LDH levels by MTT assay and LDH kit, respectively. Hoechst 33342 staining, TUNEL assay and flow cytometry were performed to evaluate the cells apoptosis. The intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) production were measured by commercial kits. In addition, the activation level of caspase-3 was evaluated using spectrophotometry and western blotting. RESULTS: Our results showed that TDF treatment significantly induced cell viability and induced apoptosis of SH-SY5Y cells and primary neuronal cells. Furthermore, the ROS levels and MDA productions were significantly up-regulated in nerve cells treated with TDF.  CONCLUSION: Our findings indicated that TDF may induce neuronal cell apoptosis through increasing the intracellular ROS and the expression level of caspase-3, which may be related to the increasing prevalence of HAND.


Assuntos
Neuroblastoma , Humanos , Tenofovir/toxicidade , Caspase 3 , Espécies Reativas de Oxigênio , Neurônios
5.
Adv Sci (Weinh) ; 10(23): e2301337, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37211690

RESUMO

Mesenchymal migration usually happens on adhesive substrates, while cells adopt amoeboid migration on low/nonadhesive surfaces. Protein-repelling reagents, e.g., poly(ethylene) glycol (PEG), are routinely employed to resist cell adhering and migrating. Contrary to these perceptions, this work discovers a unique locomotion of macrophages on adhesive-nonadhesive alternate substrates in vitro that they can overcome nonadhesive PEG gaps to reach adhesive regions in the mesenchymal mode. Adhering to extracellular matrix regions is a prerequisite for macrophages to perform further locomotion on the PEG regions. Podosomes are found highly enriched on the PEG region in macrophages and support their migration across the nonadhesive regions. Increasing podosome density through myosin IIA inhibition facilitates cell motility on adhesive-nonadhesive alternate substrates. Moreover, a developed cellular Potts model reproduces this mesenchymal migration. These findings together uncover a new migratory behavior on adhesive-nonadhesive alternate substrates in macrophages.


Assuntos
Macrófagos , Macrófagos/fisiologia , Movimento Celular/fisiologia
6.
Medicine (Baltimore) ; 101(49): e31829, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36626421

RESUMO

INTRODUCTION: Traditional Chinese exercises have become an important part of cardiac rehabilitation. It can coordinate the essence, qi, and spirit of the human body, and has the functions of promoting joints, stretching muscles and bones, ventilating and blood circulation, so as to achieve the balance between hardness and softness, and between yin and yang. We hope that the research results based on systematic review and meta-analysis will provide a theoretical basis for the treatment of atrial fibrillation (AF) with traditional Chinese exercise. METHODS: The systematic review will be performed according to the Cochrane Handbook for Systematic Reviews of Interventions. The protocol is being reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols Statement. An literature search strategy will be developed and adapted for 9 databases. Searches will be run from the database inception until the date of the search implementation and be updated before the review is completed. Meta analysis will be performed using Review Manager 5.3 and R packages. CONCLUSION: This protocol introduces a systematic review and meta-analysis of traditional Chinese exercises in the treatment of nonvalvular AF and will clarify the efficacy and safety of traditional Chinese exercises in the treatment of AF. This will further provide theoretical support for clinical treatment of AF.


Assuntos
Fibrilação Atrial , Medicina Tradicional Chinesa , Humanos , Fibrilação Atrial/terapia , População do Leste Asiático , Medicina Tradicional Chinesa/métodos , Metanálise como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
7.
Medicine (Baltimore) ; 100(50): e28084, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34918662

RESUMO

BACKGROUND: Migraine is a chronic paroxysmal neurovascular disease in which pain on one or both sides of the head is the main manifestation and is accompanied by other neurological manifestations. Clinical practice has shown that cutting therapy as a complementary alternative medicine can play a role in relieving migraine attacks. However, there is no consensus on the efficacy of cutting treatment in the treatment of migraine. The aim of this study was to conduct a meta-analysis to systematically evaluate the efficacy and safety of cutting therapy in the treatment of migraine. METHODS: First, databases were searched for relevant literature. The main databases we searched were PubMed, the Web of Science, MEDLINE, Embase, Cochrane Library, the Chinese National Knowledge Infrastructure, the Chinese Science Journal Database, Wanfang Data, and the Chinese Biomedical Literature Database. The keywords searched were "cutting treatment," " traditional Chinese medicine cutting treatment," and "migraine." The search was conducted from inception to November 2021. Second, 2 reviewers independently completed the process of study selection, data extraction, risk of bias assessment and data synthesis in strict accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols statement guidelines. Finally, we will use Review Manager Version 5.3 software for meta-analysis. RESULTS: This study will provide the most recent evidence related to the treatment of migraine by cutting therapy. CONCLUSION: The results of this systematic evaluation will provide an objective evidence-based framework for judging the effectiveness and safety of cutting therapy in the treatment of migraine.


Assuntos
Medicina Tradicional Chinesa , Transtornos de Enxaqueca/terapia , Humanos , Metanálise como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
8.
Int J Mol Med ; 45(5): 1591-1600, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32323745

RESUMO

Adipose tissue­derived stem cells (ASCs) are beneficial for myocardial regeneration. The physiological oxygen content of human organs is estimated to range between 1 and 11%. However, in the majority of previous in vitro studies with cultured ASCs, the O2 concentration was artificially set to 21%. The present study aimed to compare the protective effects of rat ASCs on neonatal rat ventricular myocytes (NRVMs) under normoxic (21% O2) and physioxic (5% O2) conditions. Rat NRVMs cultured under normoxia or physioxia were treated with H2O2 or left untreated, and further co­cultured with ASCs in 21% or 5% O2. The apoptosis of NRVMs was evaluated by Annexin V staining and quantitating the protein levels of Bcl­2 and Bax by western blotting. The oxidative stress of NRVMs was determined by a glutathione/oxidized glutathione assay kit. The concentrations of secreted vascular endothelium growth factor (VEGF), insulin like growth factor­1 (IGF­1) and basic fibroblast growth factor (bFGF) in the culture medium were quantified by enzyme­linked immunosorbent assay. Under both normoxia and physioxia, co­culture with ASCs protected H2O2­exposed NRVMs from apoptosis and significantly alleviated the oxidative stress in NRVMs. The protective effects of ASCs were associated with increased secretion of VEGF, IGF­1 and bFGF. ASCs cultured in 5% O2 exhibited certain cardioprotective effects against H2O2 stress. The results of the present study suggested that O2 concentrations influenced the cardioprotective effects of ASCs. VEGF, IGF­1 and bFGF may serve a role in the myocardial regeneration mediated by transplanted ASCs.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Secreções Corporais/metabolismo , Cardiotônicos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco/metabolismo , Animais , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura/métodos , Meios de Cultivo Condicionados/metabolismo , Peróxido de Hidrogênio/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Environ Sci Pollut Res Int ; 25(25): 25243-25254, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29943126

RESUMO

The remediation of heavy metal-contaminated soils is a great challenge and an important issue for global environmental sciences and engineering. Soil washing technology is popularly used for soil remediation, but there are issues that must be solved. These include selecting an environmentally friendly washing solution and preventing damage to the soil during the washing process. The aim of the present work is to reveal the effects of operational conditions on soil remediation contaminated by lead/cadmium, and the effects on soil physicochemical properties caused by the washing reaction. A loess soil sample was collected from northwestern China, and a humificated straw solution was used as the washing solution. The remediation efficiency was investigated using a small-scale experimental device. The remediation efficiency could be improved by optimizing the operational conditions, and we found that the Elovich equation fits better the reaction process compared to the double-constant equation and the first-order kinetics equation. The washing rate of cadmium was slightly faster than that of lead. Compared to the topsoil in the column, the concentration of lead/cadmium was higher in the bottom soil, and the content of lead/cadmium in the inner layer soil was lower than that in the outer layer soil. The washing process had little influence on the surface characteristics and functional groups of soil. The humificated straw solution could be used effectively to remove lead/cadmium and preserve nutrients in loess soil.


Assuntos
Conservação dos Recursos Naturais , Recuperação e Remediação Ambiental/métodos , Substâncias Húmicas , Metais Pesados/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Cádmio/análise , Cádmio/isolamento & purificação , China , Chumbo/análise , Chumbo/isolamento & purificação , Metais Pesados/análise , Solo/química , Poluentes do Solo/análise
10.
Environ Sci Pollut Res Int ; 25(2): 1486-1496, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29090448

RESUMO

Permeable reactive barrier (PRB) is potentially effective for groundwater remediation, especially using environmentally friendly mixed fillers in representative areas, such as semi-arid loess region in northwestern China. The mixed materials, including corn straw (agricultural wastes), fly ash (industrial wastes), zeolite synthesized from fly ash (reutilized products), and iron-manganese nodule derived from loess (materials with regional characteristics) in northwestern China, were chosen as PRB media to reduce the contents of lead and cadmium in simulated groundwater. A series of lab-scale column experiments were investigated, and the response surface methodology (RSM) was used to optimize the working process; Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) were applied to further reveal the reaction mechanism. It shows that the purification efficiencies are more acceptable when the concentrations of lead and cadmium are approximately 7 and 0.7 mg/L, respectively, at 25 °C in weakly acidic solution, and functional groups of -OH and C=C play an important role for contaminants removal. The mixed adsorbents used are effective to remove lead and cadmium in groundwater. This is the first report on the removal of lead and cadmium from groundwater in loess region in northwestern China using PRB filled with environmentally friendly mixed adsorbents.


Assuntos
Cádmio/isolamento & purificação , Conservação dos Recursos Naturais , Água Subterrânea/química , Chumbo/isolamento & purificação , Purificação da Água/métodos , Cádmio/química , China , Ferro/química , Chumbo/química , Manganês/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/química
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2076-81, 2016 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30035888

RESUMO

Phytoremediation is a novel method with great potential for site remediation contaminated by heavy metals in future. The cell wall of plant roots is significant to affect the remediation efficiency, for it is related to the multi-interface of heavy metals, pedosphere and plant. The relationship between cell wall of plant and heavy metals is complicated, containing the reaction behavior of physical chemistry, physiology and biochemistry. At present, the spectral technologies are not adequately used to investigate the in-situ response characteristics between cell wall of plant roots and heavy metals. The Calendula officinalis seedlings, the remediation plant in loess, were used as experimental sampleswhile the root characteristic variation was revealed on cell wall. The approaches of X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Raman spectra were applied to analyze the response effect of cell wall to lead/cadmium stress. The results showed: the cell wall appears to be shrinking, and certain amounts of dark particles appear on cell wall. The contents of lead/cadmium increase greatly as shown from XRF, while the representative crystals of lead/cadmium are hardly detected. The absorbance peak at 3 416 cm-1 indicates the coordination effect between lead/cadmium and ­OH in FTIR, and the movement of absorbance peaks, from 1 701 to 1 736 cm-1 and 1 593 to 1 618 cm-1, respectively, indicates the different characteristics of protein in cell wall of Calendula officinalis seedlings roots under lead/cadmium stress. The Raman intensity of absorbance peak at 2 960 cm-1 increases under lead/cadmium stress, and it proves the changes on arranging directions of cellulose molecules in cell wall samples. The components (Pectin, protein, cellulose, etc.) and functional groups (­OH, N­H, CO, etc.) of cell wall play an important role in the resistance process of cell wall derived from Calendula officinalis seedlings roots to the stress of lead/cadmium in loess.


Assuntos
Calendula , Biodegradação Ambiental , Cádmio , Parede Celular , Recuperação e Remediação Ambiental , Chumbo , Raízes de Plantas , Plantas , Plântula , Poluentes do Solo , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1205-10, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30052348

RESUMO

The soil washing technology is commonly used to remediate contaminated soils because of its advantages of low cost, ease handling and environmental-friendly. However, it should be noticed that the nutrient might leach simultaneously from soil in the washing process, and the technical solution of the issue will greatly accelerate the application process of washing technology in site remediation. This paper aims to reveal the regulating mechanism of synthesized anion adsorbent from straw on nutrient leaching potential through approaches of adsorption equilibrium models (isotherms and kinetics) and spectral analysis instruments (SEM and FTIR). The results showed: the Langmuir isotherm and pseudo second order kinetic equation fit better the adsorption behavior of nitrate and phosphate. The maximum adsorption capacity (qm), calculated with Langmuir isotherm, are 7.507 5 and 4.194 6 mg·g-1, respectively, and the reaction belongs to the monolayer and favorable adsorption with chemical adsorption the rate-determining step. The activation energy of adsorption for nitrate and phosphate at 298 K are 42.25 and 39.38 kJ·mol-1, respectively, and the reaction is spontaneous and endothermic. The purified water and KOH solution are effective for the regeneration of anion adsorbent, the desorption effect is better for the assistance of ultrasonic sound and longer desorption time. The surface of anion adsorbent after adsorption is covered with particles, while less spray-like component appears after desorption with purified water. The movement of vibration peaks in FTIR spectra indicates the effect of electrostatic interaction in the reaction. The adsorption of nitrate and phosphate on anion adsorbent involves simultaneously the effects of physical and chemical adsorption.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2442-6, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30074344

RESUMO

As an environmentally-friendly technology attracting great attention from current researchers, phytoremediation is significant for site remediation contaminated by heavy metals. The plant will appear related physiological response to reduce direct harm caused by the stress of heavy metals. The microscale behavior is always multi-dimensional and difficult to detect. The advanced instruments are effective to resolve the scientific issues, while the related researches are seldom investigated. Taking calendula officinalis seedlings as experimental samples, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR) were applied to compare the surface characteristics and functional groups variation, respectively. The response process and tolerance mechanism of calendula officinalis seedlings to lead and cadmium stress were further analyzed. The results showed: with the increasing concentration of lead and cadmium in loess, the calyptra of calendula officinalis seedlings become bending and wilting; the amount of root hairs decreases greatly while no significant variations of aerial parts are found on surface characteristics. The stress of lead and cadmium are responsible for the difference of FTIR spectra of Calendula officinalis seedlings. The peak absorbance at 3 573 cm-1 decreases and the peak becomes more complex with the increasing contents of lead and cadmium. It might be the coordination effect between lead/cadmium and hydroxyl, which affects the synthesis and secretion of organic matters. The movement of C­H vibration peak is associated with the lipid oxidationwhile the changes at 1 631 and 1 574 cm-1 suggest the protein component differences. The shifting peak at 1 385 cm-1 might be associated with the methylation of pectin and lipid, and the behavior is positive for the adaption process of calendula officinalis seedlings to lead and cadmium stress. The FTIR spectra are effective to reveal the phytoremediation mechanism on heavy metals contamination in pedosphere.


Assuntos
Calendula , Biodegradação Ambiental , Cádmio , Recuperação e Remediação Ambiental , Chumbo , Plântula , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2625-8, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30074377

RESUMO

Atomic absorption spectrometry (AAS) is widely used in the analysis and detection of heavy metals. The optimal operation conditions on metals detection are important for the stabilization and repeatability of scientific research, which affects the expected investigation objectives greatly. Thus, it becomes a key issue to establish appropriate detection methods in scientific works. Calendula officinalis was used for lead/cadmium remediation in contaminated loess, and the flame atomic absorption spectrometry (FAAS) with wet digestion was applied to analyze the contents of lead/cadmium in Calendula officinalis seedlings. The investigation data was further studied to reveal the bioaccumulation efficiency of lead/cadmium in Calendula officinalis seedlings. The results showed: the limits of detection are 0.104 and 0.007 mg·L-1 for lead and cadmium; the recovery rates of lead and cadmium are from 94.33% to 110.78% and 97.73% to 107.50% respectively. The relative standard deviations (RSD) are between 4.11% and 4.75% for lead while between 1.11% and 2.77% for cadmium,and It's been proved that the method is accurate and reliable. The low accumulation efficiency of lead with Calendula officinalis seedlings might be related to the electronegativity of lead while the growth period of calendula officinalis seedlings and environmental factors. The accumulation content of cadmium is 104.85 mg·kg-1 with cadmium concentration of 50 mg·kg-1. The co-existing of lead in loess is positive for cadmium accumulation by Calendula officinalis seedlings, and the synergistic effect might work in the process. The established detection method is effective for quantitative analysis of lead and cadmium in calendula officinalis seedlings and significant for future research.


Assuntos
Biodegradação Ambiental , Calendula , Cádmio , Chumbo , Plântula , Espectrofotometria Atômica
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2852-7, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30084614

RESUMO

The various characteristics of DOM have great impact on the transformation process of contaminants in soil due to the generation of the feedback regulation in cycles of plant, Rhizosphere soil and environmental contaminants. Currently, more attention was paid on contaminants behaviors of adsorption, transformation, accumulation and detoxification than DOM derived from Rhizosphere soil. The chemical speciation of lead/cadmium and growth efficiency related variations were revealed in the growth process of Calendula officinalis seedlings, and the spectral characteristics of DOM in Rhizosphere loess were discussed with UV, FT-IR and 3D-EEMs spectra. The results showed: the dominant contents of lead/cadmium are in residual and exchangeable speciation, and the exchangeable contents increase greatly after the growth of Calendula officinalis seedlings. It causes negative effects on the height and emergency rate of Calendula officinalis seedlings with lead/cadmium, and the Calendula officinalis is able to positively improve loess characteristics. The root of Calendula officinalis appears to be longer, thinner and flexuous. The maximum absorption band of DOM in UV spectra locates in 200~240 nm, and the sharper and greater intensity of peaks can be detected under lead/cadmium stress. The absorption peaks in FT-IR spectra move from 3 444 and 1 637 to 3 440 and 1 645 cm-1, respectively, indicating the combination effects between metal ions and functional groups of­OH and CO. The dominant fluorescence peaks of DOM are found to be aroundλex/em=240/430, described as fulvic-acid like components, and metals in loess affect more on peaks intensity than locations. The characteristics of DOM in Rhizosphere loess of Calendula officinalis seedlings contain much micro-eco-environmental information, and the spectral approaches are efficient to reveal the relationship between DOM and chemical speciation of lead/cadmium.


Assuntos
Calendula , Rizosfera , Cádmio , Chumbo , Plântula , Solo , Poluentes do Solo , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2863-9, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30084616

RESUMO

As the representative component for eco-environmental researchers, dissolved organic matter (DOM) is playing a significant role for the indication effect on environmental quality and efficiency assessment on remediation approaches. Nowadays, it lacks related investigation on DOM derived from rivers and sediments, and the advanced discussion is in urgent need because of the dynamic variations of experimental target, such as spatial-temporal condition, hydrological condition, environmental condition and research dimension. The spectral approaches, including elemental analysis, ultraviolet spectra (UV), Fourier transform infrared spectroscopy (FT-IR), Raman spectra (Raman), three dimensional excitation emission matrix fluorescence spectroscopy (3D-EEMs) and nuclear magnetic resonance (NMR) were used to reveal the characteristics of DOM derived from water and sediment samples in the intersection zone of Jing River and Wei River (Gaoling District, Xi'an City, Shaanxi Province). The results showed: the ratios of H/C and N/C for DOM in sediment are higher than that of DOM in water, suggesting the saturation degree in DOM from sediment are higher with more content of nitrogen. The UV absorbance of DOM decreases with the increasing of wave length, and obvious absorption region (240~310 nm) appears in DOM from sediment. The functional groups of ­OH, CC and C­O could be found in DOM from FTIR spectra, and the characteristics might be more complicated in sediment for various peak shapes and intensities. The Raman spectra of DOM in water are similar to that of the sediment. The fluorescence peaks of DOM in water are regarded as visible tryptophane-like and UV fulvic-like components, mainly from terrestrial source; while fluorescence peaks of DOM in sediment belong to UV fulvic-like fluorescence without protein-like fluorescence peaks being detected. The principal carbon chains are similar in DOM samples from water and sediment, and the aliphatic characteristics are more obvious for the latter, which contains more carbohydrate-binding hydrogen than aromatic-binding hydrogen and γ-H. It proves that DOM in water mainly comes from terrestrial source, and DOM in sediment is more complicated and fresher. The achievements are significant to reveal the microscopic characteristics and environmental behavior of DOM in representative systems.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1587-91, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26601372

RESUMO

Tannery industry is one of the major traditional industries and important wastewater sources in China. The existing research mainly focus on the quality of inlet and outlet water, rather than the purification and transformation behavior of dissolved organic matter (DOM) in the treatment process of tannery wastewater. The UV spectra and fluorescence spectroscopy were used to detect the spectral characteristics of water samples in the treatment process, and it is analyzed that the formation process and the linear relationships between total fluorescence intensity and parameters. The results showed: the UV absorbance of DOM in wastewater increased firstly and then decreased with longer wavelength, and the wave peaks were found around the wavelength of 230 nr. The values of A253 /A203 and SUVA254 increased firstly and then decreased, indicating the complex reaction process related to free substituent and aromatic rings. The fluorescence peaks appeared at the regions of λ(ex/em) = 320-350/440- 460 and λ(ex/em) = 270-300/390-420, referred as visible humic-like and visible fulvic-like fluorescence, respectively. With the treatment process of tannery wastewater, the following fluorescence phenomenon were monitored, such as the blue-shift of humic-like fluorescence peak in the hydrolytic acidification tank, the appearance of tryptophan fluorescence peak in the second biochemical pond (λ(ex/em) = 290/340), the weak fluorescence peak in the fourth biochemical pond (λ(ex/em) = 350/520) and the stabilized fluorescence characteristics in the secondary sedimentation tank and water outlet. The achievements are helpful to investigate the degradation and formation behavior of water components, and significant for the fluorescence variation analysis in the treatment system. The removal rate of total fluorescence intensity of tannery wastewater fit better the removal rate of TOC with coefficient of r 0.835 5. The UV spectra and 3D-EEMs are effective to reveal the purification behavior and mechanism of tannery wastewater.


Assuntos
Compostos Orgânicos/análise , Curtume , Águas Residuárias/análise , Resíduos Industriais/análise , Análise Espectral , Purificação da Água
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1203-7, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26415428

RESUMO

Nowadays, the wastewater quantity discharged yearly from tannery industry is around 0. 2 billion t in China. The contaminants of tannery wastewater include macromolecular organic matters, such as grease, fur scraps and collagen, and the alkaline wastewater appears to be of high content of salt and COD. The quality of tannery wastewater is monitored strictly among all kinds of industry wastewater. In the treatment process of tannery wastewater, the quality of inlet and outlet water is generally analyzed. In fact, the transformation behavior of contaminants should be additionally checked to optimize the treatment conditions. Dissolved organic matter (DOM) is commonly existed in water-bodies and helpful to understand the physicochemical characteristics, while the related work should be further studied on tannery wastewater. The approaches of elemental analysis, thermal gravimetric analysis (TG), Fourier infrared spectroscopy (FTIR) and 13C nuclear magnetic resonance (13C NMR) were used to reveal the characteristics of DOM in the treatment process of tannery wastewater. The results showed the carbon content of DOM samples increased gradually, atomic ratios of H/C increased firstly and then decreased, indicating the organic matters were decomposed into chain structures firstly, finally forming the component hard to degraded. The pyrolysis process of DOM mainly proceeded in the regions of 110~530 °C (aliphatic compound, protein, etc. ) and 530~800 °C (aromatic ring, single bond of C-C, etc. ). The functional groups of DOM included -OH, -NH2, C=O and so on, and the aromatic substances were detected, shown from FTIR figures, in the later period of the reaction, caused by the metabolism effect of micro-organism. The content of alkoxy-C increased to the maximum in the second biochemical pond, and the minimum content of aromatic-C appeared in the second biochemical pond, suggesting the transformation behavior of carbon functional groups. The investigation on DOM in tannery wastewater is significant to understand the purification mechanism of contaminants in tannery wastewater.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Curtume , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Carbono , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 447-52, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970910

RESUMO

Soil contamination is regarded as one of the most serious issues to humanity all over the world. It is statistically believed that over one-fifth of the farmland, that is 20 million ha, is found to be contaminated by heavy metals in China. And the related issues, caused by soil contamination, of food safety, human health and eco-environmental quality attract much attention by public with more serious contamination than before. The technological approach for soil remediation is widely investigated. The technology of soil washing is effective for contaminants removal, while the treatment procedure might lead to component leaching from soil system, harmful for soil fertility, physicochemical properties and ecological functions. The study of spectral characteristics on leaching component is significant for decision-making of contaminated sites remediation and ecological function recovery, while the related investigation seems weaker nowadays. The paper mainly revealed the leaching characteristics of component from Pb/Cd contaminated loess in the washing process with Ethylene Diamine Tetraacetic Acid (EDTA) in reaction column, and the research objectives included base cations, loess nutrients, clay minerals and organic matter. The variation of clay minerals was analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM), and 3D-EEM fluorescence spectrum was used for the identification of dissolved organic matter (DOM). The experimental results showed: the leaching component from loess is detected in the washing reaction. The final removal efficiency (240 min) of Pb and Cd from loess are 49. 86% and 62.25%, respectively. The sodium ions and nitrate nitrogen are the most easily leaching component, and little difference of clay minerals is identified before and after washing reaction. The fulvic acid-like (FA-like) material was firstly (10 min) detected around E(ex/em) = 240-250/320-340 and E(ex/em) = 260-290/450-470 in 3D-EEM fluorescence spectrum, and the humin acid-like (HA-like, E(ex/em) = 290-320/430-490) appeared at 60 min with weaker fluorescence intensity of FA-like (E(ex/em) = 240/320). The decreased fluorescence intensity of FA-like and HA-like, shown after 120 min and 240 min, indicated the component variation of DOM in the leaching solution. The spectroscopy approach is appropriate for characteristics identification of leaching component from co-contaminated loess.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 534-8, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970927

RESUMO

The soil contamination of heavy metals, from the areas of mine, highway, industrial area, agricultural land and so on, is nowadays a serious issue all over the world. The contamination of heavy metals in large agricultural area might lead to the decrease of products quality and economic value. Actually, the accumulation amount of heavy metals by crops is much more related to the activated speciation, which is exchangeable and able to transform to the forms of carbonates, Fe-Mn oxides, organic matter and residual. Thus, the investigation to reveal the transformation mechanism of heavy metals caused by soil conditions might be appropriate to reduce the contaminated risk to crops. The vermicular red soil from the agricultural area of central China was used as sample in the paper, and the Tessier Sequential Extraction Procedure-atomic absorption spectroscopy (AAS) was applied to discuss the chemical speciation and non-biological transformation mechanism of Pb at different conditions. The results showed: the total amount of Pb is 32.56 mg x kg(-1), lower than the first level of the State Environmental Quality Standard for Soils. The Pb content of different speciation, with decreased concentration, is residual (54.55% of total Pb content), bound to Fe-Mn oxides, bound to organic matter, bound to carbonates and exchangeable. The pH value of red soil is related to the charge amount on surface of inorganic colloids and organic matter, and the water content of red soil would change the redox potential, effective for the variation of chemical speciation of Pb. The environmental factors of straw dosage and aging time could change Pb speciation, with Pb concentration of residual form the highest. The Muller index of Igeo is 0.3025, indicating the contribution of human activities. The Tessier Sequential Extraction Procedure-AAS is effective for the non-biological transformation mechanism identification of Pb speciation in red soil.

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