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1.
Huan Jing Ke Xue ; 43(2): 762-769, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35075850

RESUMO

Nitrogen mineralization in riparian soil changes the migration and utilization efficiency of nitrogen, which is closely related to the control of water eutrophication. The differences in soil properties caused by land use alter nitrogen retention and transport capacity. Therefore, the soil of three land use types (woodland, grassland, and cultivated land) in the western riparian zone of Taihu Lake were selected for research on the dynamic changes in nitrogen mineralization amount using an incubation experiment and a leaching characteristics by soil column leaching experiment, and their environmental effects were also studied under different biochar addition conditions (0%, 1%, and 5%). The results showed that, in general, the addition of biochar inhibited nitrogen mineralization in forest land and grassland soil, whereas the effect of biochar on nitrogen mineralization in cultivated land was promoted in low concentrations but inhibited in high concentrations. Leaching experiments showed that the biochar addition reduced the loss of soil mineral nitrogen, and the reduction rate in ammonia nitrogen was 23.28%-39.79%, whereas there was little difference between the three land use types. The nitrate decreased by 17.20%-44.49%, and the reduction rate of cultivated land was smaller than that of forest land and grassland. In conclusion, the input of biochar into grassland and cultivated land can better maintain soil fertility and reduce soil nitrogen loss in riparian soil.


Assuntos
Nitrogênio , Solo , Carvão Vegetal , Lagos , Nitrogênio/análise
2.
Huan Jing Ke Xue ; 42(6): 2787-2795, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032078

RESUMO

In order to explore the characteristics and environmental significance of available nitrogen and phosphorus in different land-water transition zones, soil and sediment samples from three study areas, including the upstream watershed of Minjiang River (MJU), western watershed of Hongze Lake (HZW), and western watershed of Taihu Lake (THW), were collected and analyzed. The results showed that the contents of total nitrogen and phosphorus in THW were higher than those of other two study areas. The contents of nitrogen and phosphorus in sediments were higher than those in soils of HZW. The distribution trend of available nitrogen and available phosphorus was generally consistent with the distribution trend of total nitrogen and phosphorus. The proportions of available nitrogen and phosphorus in THW and HZW were much higher than those in MJU, and the proportions of available nitrogen and phosphorus in sediments were higher than those in soils. The physiochemical properties such as pH value, organic matter, and iron and aluminum oxides were related to the available nitrogen and phosphorus in the soil and sediment, but correlations between them were complex. The distribution patterns of available nitrogen and phosphorus in the soil and sediments of the land-water transition zone reflect the impacts of the natural environment and human activities, particularly those of the latter.

3.
Huan Jing Ke Xue ; 41(2): 914-921, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608753

RESUMO

Biochar, as a new environmentally friendly material, has been used to improve soil quality and for pollution remediation. Biochar input has a significant impact on available nutrients in the soil. Based on the different land use types (forestland, grassland, cultivated land, and barren land) in the riparian zone of Taihu Lake, the effects of biochar application on the available content of nutrients in different land use types of soil were compared, and the dynamics of nutrient change was also discussed. Results show that the addition of biochar can significantly affect the available nutrient content in riparian soil, however the influential degrees for carbon, nitrogen, and phosphorus were different. After the input of biochar, dissolved organic carbon in riparian soils showed a clear downward trend, while the available nitrogen increased slightly, and the available phosphorus increased significantly. For woodland, grassland, arable land and wasteland soils, the contents of dissolved organic carbon decreased by 33.3%, 27.4%, 29.5%, and 51.4%, while the contents of available nitrogen increased by 10.8%, 18.2%, 16.4%, and 15.2%, and the contents of available phosphorus increased by 40.0%, 50.2%, 34.0%, and 43.6%, respectively. Compared with the concentrations between the control group soil (CK) and the biochar additive group soil (BC), the concentrations of dissolved organic carbon and available phosphorus exhibited large differences between the two groups regarding available nitrogen concentrations. Among the four types of riparian soils, the effects of biochar on the availability of different nutrients were different.

4.
Huan Jing Ke Xue ; 40(5): 2186-2193, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087855

RESUMO

In order to explore the effect of land use pattern on phosphorus distribution and the potential release capacity of stream sediment in the upper Minjiang River, this paper presented organic phosphorus forms and their spatial distribution characteristics of sediments in the upper Minjiang River by using the IVANOFF method and discussing the effects of physicochemical properties of sediments on the distribution of organic phosphorus forms. The results show that:①nitrogen and phosphorus contents of sediments in Jianxi and Shaxi catchments are higher than those in the Futunxi catchment, probably related to the large number of farmland runoff and municipal sewage near the Jianxi and Shaxi catchments and the large forest area around the Futunxi catchment;②contents in the sediments from three catchments and TP contents in the sediments from Jianxi and Futunxi catchments showed the order of upper reaches < middle reaches < lower reaches, which may be caused by the mountainous and forested areas in the upper reaches and the intensive human activities in the middle and lower reaches;③nitrogen phosphorus in sediments of the three catchments were mainly non-active organic phosphorus, which indicated that upper reaches of the Minjiang river were generally less affected by external pollution, and the relative proportion of organic phosphorus in the sediments of different catchments was relatively large, while the change in different sections of the same river was relatively small;④physicochemical properties of sediments had a significant impact on the morphology and distribution of organic phosphorus, among which the effects of organic matter, TP, and TN were the most obvious, but the effects on sediments in different river basins were different. Therefore, to protect the water quality of the upper Minjiang River, it is necessary to strengthen the control of the living and agricultural pollution sources near the catchments.

5.
Scand J Clin Lab Invest ; 78(5): 373-378, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29888618

RESUMO

Bioinformatics indicate that miR-223 regulates many genes associated with cholesterol metabolism, and it could also control high-density lipoprotein-cholesterol (HDL-C) uptake. As reported in previous study, miR-223 was found to be upregulated from human subjects with familial hypercholesterolaemia, however, it remains to be determined using a larger group of coronary heart disease (CHD) patients. Moreover, whether it correlates with severity of atherogenesis, has never been elucidated before. We aim to further explore the association between circulating miR-223 content and severity of CHD. Sample was collected from 300 CHD patients and 100 subjects with angiographic exclusion of CHD. MiR-223 content was detected using quantitative real-time PCR. Gensini score was used to evaluate the severity of coronary stenotic lesions. Expression of miR-223 was identified on basis of the quartiles of the Gensini score, and association between the miRNA and CHD was analyzed. Diagnostic potential of miR-223 of CHD was performed by ROC analysis. CHD patients had higher miR-223 level (13.23, 9.29-17.59 vs. 4.05, 3.06-6.11, p < .001), and the miRNA content significantly elevated following increasing Gensini score (p < .001). Gensini score was significantly associated with miR-223 expression (r= .7289, p < .001). The optimal cut-off value of miR-223 was with a sensitivity of 86.0% and specificity of 91.3%. The AUC of miR-223 was 0.933 (95%CI, 0.905-0.961). These preliminary results suggest that the expression of miR-223 may be associated with atherogenesis. The level of circulating miR-223 in predicting the severity of coronary atherosclerosis may have a relatively certain value.


Assuntos
Aterosclerose/sangue , Ácidos Nucleicos Livres/sangue , Doença da Artéria Coronariana/sangue , MicroRNAs/sangue , Idoso , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Biomarcadores/sangue , Estudos de Casos e Controles , LDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença
6.
Nanomaterials (Basel) ; 7(2)2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28336858

RESUMO

3-Hydroxy-2-naphthoic acid hydrazide (HNH), a new reductant and modifier, was applied to reduce and modify graphene oxide (GO) in a one-step process. The obtained HNH reduced graphene oxide (HNH-rGO) was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscopy, X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectra (FTIR). The results demonstrated that GO was successfully reduced to graphene and the surface of HNH-rGO was grafted with HNH. The interlayer space was increased from 0.751 nm to 1.921 nm, and its agglomeration was much more attenuated compared with GO. HNH-rGO/polypropylene and graphene/polypropylene composites were synthesized through melt-blending method. The viscosity was enhanced with increased addition of graphene and surface modified graphene demonstrated stronger rheological behavior improving effect than the untreated graphene.

7.
Huan Jing Ke Xue ; 35(8): 2980-4, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25338369

RESUMO

The degradation efficiencies of dimethyl phthalate (DMP) by O3, O3/H2O2, Ti(IV)/O3 and Ti(IV)/O3/H2O2 were investigated under acidic conditions. The results indicated that Ti(IV)/O3/H2O2 was the best system with the highest degradation efficiency and mineralization rate of DMP, and the highest utilization rate of ozone at pH 2.8. The apparent rate constants of DMP degradation by O3, O3/H2O2, Ti(IV)/O3 and Ti(IV)/O3/H2O2 under the same conditions were 3.96 x 10(-4) s(-1), 9.54 x 10(-4) s(-1) 1.07 x 10(-3) s(-1) and 6.41 x 10(-3) s(-1), respectively. The ozone utilization rate of Ti(IV)/O3/H2O2 was improved by 6.51% compared with that of ozonation alone. The experimental results showed that the optimized concentrations of Ti(IV) and H2O2 were 1.4 mg x L(-1) and 10 mg x L(-1), respectively. According to the results of gas chromatography-mass spectrometry (GC/MS) and ion chromatography analysis, the possible reaction pathway of DMP degradation by Ti(IV)/O3/H2O2 was proposed and discussed.


Assuntos
Peróxido de Hidrogênio/química , Ozônio/química , Ácidos Ftálicos/química , Titânio/química , Poluentes Químicos da Água/química , Cromatografia Gasosa-Espectrometria de Massas
8.
Huan Jing Ke Xue ; 34(10): 3879-87, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24364306

RESUMO

A micro power turbine water aeration system with a water biological base and a sediment biological base was independently developed, aimed at urban water eutrophication. The results showed that the average removal rates of COD, NH+4 -N, TP by the water biological base were 82. 33% , 98. 00% and 54. 73% , respectively; The sediment reduction rate achieved by the sediment biological base could reach 20% within 5 days, and aeration in the overlying water could relieve the nutrient releasing caused by the degradation of organic matter; The effect of nutrient removal and organic matter reduction in sediment by the combined ecological restoration technology was perfect in pilot scale. The average removal rates of COD, NH+4 -N, TP were 52. 0%, 33. 6% and 23.4%, respectively, and the organic content in sediment was reduced from 38. 20% to 12.20% .


Assuntos
Água Doce/química , Sedimentos Geológicos/química , Purificação da Água/métodos , Compostos de Amônio/análise , Análise da Demanda Biológica de Oxigênio , Cidades , Eutrofização , Nitrogênio/análise , Fósforo/análise , Poluentes Químicos da Água/análise
9.
PLoS One ; 8(6): e63656, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23750203

RESUMO

Oxidative stress is considered to be a major factor contributing to pathogenesis and progression of many diseases. A novel andrographolide-lipoic acid conjugate (AL-1) could protect pancreatic ß-cells from reactive oxygen species (ROS)-induced oxidative injury. However, its protective mechanism is still unclear. In this work, we used proteomics to identify AL-1-regulated proteins in ß-cells and found that 13 of the 71 proteins regulated by AL-1 were closely associated with antioxidation. These differential proteins were mainly involved in the ERK1/2 and AKT1 signaling pathways. Functional investigation demonstrated that AL-1 exerted its protective effects on H2O2-induced cell death of ß-cells by generating NADPH oxidase-dependent ROS to activate ERK1/2 and AKT1 signaling pathways. As a consequence, the expressions of antioxidant proteins including Trx1, Prx1 and Prx5, and anti-apoptotic proteins including PDCD6IP, prohibitin, galectin-1 and HSP were upregulated. AL-1 probably worked as a "vaccinum" to activate the cellular antioxidant system by inducing the generation of low concentration ROS which then reciprocally protected ß-cells from oxidative damage caused by high-level ROS from H2O2. To the best of our knowledge, this is the first comprehensive proteomic analysis illustrating a novel molecular mechanism for the protective effects of antioxidants on ß-cells from H2O2-induced cell death.


Assuntos
Citoproteção/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia , Células Secretoras de Insulina/citologia , Espécies Reativas de Oxigênio/metabolismo , Ácido Tióctico/química , Animais , Antioxidantes/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Peróxido de Hidrogênio/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Proteômica , Ratos , Regulação para Cima/efeitos dos fármacos
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