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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2946-50, 2016 Sep.
Article in Chinese | MEDLINE | ID: mdl-30085484

ABSTRACT

Increased concentration of air respirable particulate matter associated with a number of combination factors. Spatial dispersion is also correlated with elevation DEM. In order to study the fog haze pollution associated with digital elevation model of spatial relations, this paper used the capital area ring within 100 km as the research scope, partitioning different length scale grid according to the rectangular grid method in the study area, obtaining visible light image data and hyperspectral image data by using unmanned aerial vehicle (UAV) for the extraction and integration air pollution factor and elevation factor within the scope of this study. GS+ software of kriging interpolation method was used to research the spatial correlation of variable data extraction; the MODIS remote sensing image data combined with field survey were used to analyze nonlinear regression of the terrain and environmental data. With the Calculation of variation effects of the particulate matter in the air and the spatial of the elevation factor under different grid scale ring of capital region, an optimization model of spatial correlation between them was established. Then the relation between the concentration of PM10 and height was determined. The biggest influence distance of elevation DEM associated with particulate matter API is 14.74 km. DEM space since the correlation of waning with the increase of the distance between sample points, which is also an important innovation of this paper. This result shows that the spatial correlation between the elevation DEM and environment conforms to the statistical spherical Gaussian model, correlation coefficient R2 were over 90%, which model fittings good. This study provides a certain theoretical and practical guidance for the control of air pollution index in the future as the change of height to select different tree species for afforestation.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1649-55, 2014 Jun.
Article in Chinese | MEDLINE | ID: mdl-25358181

ABSTRACT

Basin soil type, moisture content and vegetation cover index are important factors affecting the basin water of Yongding River, using traditional sampling method to investigate soil moisture and the watershed soil type not only consuming a lot of manpower and material resources but also causing experimental error because of the instrument and other objective factors. This article selecting the Yongding River Basin-Beijing section as the study area, using total station instruments to survey field sampling and determination 34 plots, combined with 6 TM image data from 1978 to 2009 to extract soil information and the relationship between region's soil type, soil moisture and remote sensing factors. Using genetic algorithms normalization to select key factors which influenced NDWI, which is based on the green band and near-infrared bands normalized ratio index, usually used to extract water information in the image. In order to accurate screening and factors related to soil moisture, using genetic algorithms preferred characteristics, accelerate the convergence by controlling the number of iterations to filter key factor. Using multiple regression method to establish NDWI inversion model, which analysis the accuracy of model is 0.987, also use the species outside edges tree to meet accuracy test, which arrived that soil available nitrogen, phosphorus and potassium content and longitude correlation is not obvious, but a positive correlation with latitude and soil, inner precision researched 87.6% when the number of iterations to achieve optimal model calculation Maxgen. Models between NDWI and vegetation cover, topography, climate ect, through remote sensing and field survey methods could calculate the NDWI values compared with the traditional values, arrived the average relative error E is -0.021%, suits accord P reached 87.54%. The establishment of this model will be provide better practical and theoretical basis to the research and analysis of the watershed soil moisture and organic of Yongding River.


Subject(s)
Remote Sensing Technology , Soil , Water , Algorithms , Climate , Models, Theoretical , Nitrogen , Phosphorus , Potassium , Rivers
3.
Zhonghua Gan Zang Bing Za Zhi ; 19(1): 29-33, 2011 Jan.
Article in Chinese | MEDLINE | ID: mdl-21272455

ABSTRACT

To compare the efficacy of interferon and thymosin alpha-1 combination therapy with interferon monotherapy for HBeAg positive chronic hepatitis B. The relevant randomized controlled trials were searched throughout PubMed, EBSCO, Cochrane Library, CBMdisc, VIP, WanFang since Janurary 1990. Studies were included if patients were followed up for at least 6 months after cessation of treatment. Meta-analysis was carried out with RevMan5.0 software. Subgroup analyses were used at different time of observation. Seven randomized controlled trials were included(535 patients in total). According to the results of meta-analysis, the combination therapy was remarkably more effective than monotherapy both at the end of the treatment and the follow-up in terms of HBV-DNA negative rate (54.9% vs 36.3%, OR=2.39, 95% CI=1.64-3.49, P value is less than 0.01; 58.6% vs 30.7%, OR=3.68, 95% CI=2.51-5.41, P value is less than 0.01, respectively), ALT normalization rate (74.5% vs 60.9%, OR=1.94, 95% CI=1.26-3.00, P value is less than 0.01; 74.0% vs 55.6%, OR=2.36, 95% CI=1.54-3.62, P value is less than 0.01, respectively), HBeAg loss rate (56.9% vs 36.7%, OR=2.38, 95% CI=1.61-3.51, P value is less than 0.01; 62.2% vs 33.2%, OR=3.42, 95% CI=2.31-5.06, P value is less than 0.01, respectively) , and HBeAg seroconversion rate (40.1% vs 29.0%, OR=1.65, 95% CI=1.10-2.47, P value is less than 0.05; 47.0% vs 29.5%, OR=2.13, 95% CI=1.43-3.16, P value is less than 0.01, respectively); the HBsAg loss rate of the combination therapy group was significantly higher than that of the monotherapy group only at the end of the follow-up (9.8% vs 3.7%, OR=2.92, 95% CI=1.09-7.76, P value is less than 0.05). Interferon and thymosin alpha-1 combination therapy achieves superior effect with no increase in the adverse effects as compared to interferon monotherapy for HBeAg positive chronic hepatitis B.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B, Chronic/drug therapy , Interferons/therapeutic use , Thymosin/analogs & derivatives , Drug Therapy, Combination , Hepatitis B e Antigens/blood , Hepatitis B, Chronic/blood , Humans , Randomized Controlled Trials as Topic , Thymalfasin , Thymosin/therapeutic use , Treatment Outcome
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 8(1): 9-12, 2006 Feb.
Article in Chinese | MEDLINE | ID: mdl-16522230

ABSTRACT

OBJECTIVE: To study the changes of serum interleukin-15 (IL-15) levels and the expression of CD4(+)T (T-helper lymphocyte) subsets CD4(+)CD45RA(+) and CD4(+)CD45RO(+) in peripheral blood of children with juvenile rheumatoid arthritis (JRA). METHODS: The serum concentration of IL-15 was detected using ELISA in 39 children with JRA. The expressions of CD4(+)CD45RA(+)T and CD4(+)CD45RO(+)T in peripheral blood were detected by flow cytometry in 24 out of the 39 patients with JRA. Twenty-six age and sex-matched healthy children were used as the Control group. RESULTS: The mean serum IL-15 level in JRA patients was significantly higher than that in controls (1.37 +/- 0.98 pg/mL vs 0.96 +/- 0.41 pg/mL, P <0.05). Among the 39 JRA patients, the serum IL-15 level in 17 patients with systemic JRA increased remarkably (P < 0.01), but not in patients with the other two types of JRA, the oligoarthritis and polyarthritis (n=13, n=9, respectively), compared with that in controls. The mean serum IL-15 level of the JRA patients was significantly reduced after conventional treatment (P < 0.01). The serum IL-15 level in JRA patients positively correlated with white blood cell count (r=0.347, P <0.05) and C reactive protein (r=0.452, P < 0.01) but not with the erythrocyte sedimentation rate. The patients with high serum IL-15 levels (> or = medium level 1.73 pg/mL) had higher expression of CD4(+)CD45RO(+)T than those with low serum IL-15 levels (< medium level) (16.29 +/- 5.46% vs 11.75 +/- 3.15 %, P < 0.05). CONCLUSIONS: The serum IL-15 levels in JRA patients increased significantly. An increased IL-15 level can transform CD45RA into CD45RO in peripheral blood of patients with JRA, and then result in T lymphocyte activation and mediate the immunopathological impairment. IL-15 may be used a marker for the evaluation of severity of JRA.


Subject(s)
Arthritis, Juvenile/immunology , CD4 Antigens/analysis , Interleukin-15/blood , Leukocyte Common Antigens/analysis , T-Lymphocytes, Helper-Inducer/immunology , Adolescent , Child , Child, Preschool , Female , Humans , Male
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