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1.
Neurol Neurochir Pol ; 51(6): 459-464, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28826918

RESUMO

OBJECTIVES: To investigate the key surgical points in treating split cord malformations associated with osseous divide and scoliosis (SCM-OD-S). MATERIALS AND METHODS: The surgical options and methods of a total of 142 SCM-OD-S cases were retrospectively analyzed, and the surgical precautions and imaging diagnosis were also discussed. RESULTS: The 142 patients were performed osseous divide resection plus dural sac molding, which achieved good results and no serious complication such as spinal cord and nerve injury occurred; certain symptoms such as urination-defecation disorders, muscle strength subsidence, Pes Cavus, and toe movement disorder in partial patients achieved various degrees of relief, and it also created good conditions for next-step treatment against scoliosis. CONCLUSIONS: The diagnosis of SCM-OD mainly depended on imaging inspection, routine magnetic resonance imaging (MRI) combined with computed tomography (CT) 3D reconstruction, which can comprehensively evaluate the types and features of diastematomyelia as well as other concomitant diseases. SCM alone needed no treatment, but surgery will be the only means of treating SCM-OD. Intraoperatively removing osseous divide step-by-step, as well as carefully freeing the spinal cord and remodeling the dural sac, can lay good foundations for relieving tethered cord, improving neurological symptoms, and further scoliosis orthomorphia, thus particularly exhibiting importance for the growth and development of adolescents.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Medula Espinal/anormalidades , Medula Espinal/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Escoliose/etiologia , Escoliose/cirurgia , Adulto Jovem
2.
World J Gastrointest Oncol ; 15(5): 787-809, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37275445

RESUMO

BACKGROUND: Circular RNAs (circRNAs) have attracted extensive attention as therapeutic targets in gastric cancer (GC). Circ_0003356 is known to be downregulated in GC tissues, but its cellular function and mechanisms remain undefined. AIM: To investigate the role of circ_0003356 in GC at the molecular and cellular level. METHODS: Circ_0003356, miR-668-3p, and SOCS3 expression were assessed via quantitative real time-polymerase chain reaction (qRT-PCR). Wound healing, EdU, CCK-8, flow cytometry and transwell assays were used to analyze the migration, proliferation, viability, apoptosis and invasion of GC cells. The subcellular localization of circ_0003356 was monitored using fluorescence in situ hybridization. The interaction of circ_0003356 with miR-668-3p was confirmed using RIP-qRT-PCR, RNA pull-down, and dual luciferase reporter assays. We observed protein levels of genes via western blot. We injected AGS cells into the upper back of mice and performed immunohistochemistry staining for examining E-cadherin, N-cadherin, Ki67, and SOCS3 expressions. TUNEL staining was performed for the assessment of apoptosis in mouse tumor tissues. RESULTS: Circ_0003356 and SOCS3 expression was downregulated in GC cells, whilst miR-668-3p was upregulated. Exogenous circ_0003356 expression and miR-668-3p silencing suppressed the migration, viability, proliferation, epithelial to mesenchy-mal transition (EMT) and invasion of GC cells and enhanced apoptosis. Circ_0003356 overexpression impaired tumor growth in xenograft mice. Targeting of miR-668-3p by circ_0003356 was confirmed through binding assays and SOCS3 was identified as a downstream target of miR-668-3p. The impacts of circ_0003356 on cell proliferation, apoptosis, migration, invasion and EMT were reversed by miR-668-3p up-regulation or SOCS3 down-regulation in GC cells. CONCLUSION: Circ_0003356 impaired GC development through its interaction with the miR-668-3p/SOCS3 axis.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 494-499, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812420

RESUMO

OBJECTIVE: To investigate the effect of long non-coding RNA-TUC338 on the proliferation and migration of lymphoma cells. METHODS: The expression of TUC338 in different lymphoma cells was detected by fluorescence quantitative PCR, cell proliferation by sulforhodamine B (SRB) assay, migration of lymphoma cells by transwell assay, and protein expression in PI3K/AKT signaling pathway by Western blot. RESULTS: The expression levels of TUC338 in lymphoma cells Daudi, U937, BC-3, and Raji significantly increased in comparison with human normal T lymphocytes H9 (t=13.277, 10.103, 16.200, and 26.687, P=0.002, 0.005, 0.001, and 0.000). Compared with NC-siRNA group, the number of cells crossing the chamber of TUC338-siRNA group was significantly reduced (t=30.508, P=0.000), the protein expression levels of p-PI3K and p-AKT significantly decreased (t=16.872 and 18.371, P=0.000 and 0.000), and OD530 absorbance values at 24 h, 48 h, and 72 h were significantly lower (P<0.05). CONCLUSION: The expression of TUC338 significantly increases in lymphoma cells, and silence of TUC338 effectively inhibits the activation of PI3K/AKT signaling pathway, thereby inhibiting the proliferation and migration of lymphoma cells, which has a potential application value in diagnosis and treatment of lymphoma.


Assuntos
RNA Longo não Codificante , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(3): 876-880, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32552951

RESUMO

OBJECTIVE: To investigate the expression of Circ_cgga162 in serum of mantle cell lymphoma (MCL) patients and analyze its potential as a prognostic biomarker. METHODS: The expression of Circ_cgga162 in 86 cases of mantle cell lymphoma and 50 cases of lymph node reactive hyperplasia (RH) were detected by real-time quantitative polymerase chain reaction (qRT-PCR). The relationship between the expression of Circ_cgga162 and clinicopathological features was analyzed by univariate analysis. The relationship of Circ_cgga162 expression with progression-free survival time and overall survival time was analyzed by Kaplan-Meier. The relationship between expression of Circ_cgga162 and prognosis of patients was analyzed by univariate and multivariate analysis. RESULTS: The expression level of Circ_cgga162 in MCL patients was significantly higher than that in control (RH) group (P<0.01). The expression of Circ_cgga162 not correlated with age, gender, B symptoms and LDH (all P>0.05), but correlated with the expression of MCL International Prognostic Index (IPI), Ann Arbor stage, bone marrow infiltration and Ki67 (all P<0.05). In addition, Kaplan-Meier analysis showed that the progression-free survival time and overall survival time of the MCL patients with high expression of Circ_cgga162 were significantly shorter than those of the MCL patients with low expression (P<0.01). Univariate analysis showed that Ann Arbor stage, Circ_cgga162 expression, MIPI, bone marrow infiltration and Ki67 were the prognostic factors for MCL patients (all P<0.05). Multivariate Cox regression analysis showed that Ann Arbor stage, Circ_cgga162 expression and MIPI were independent factors affecting the prognosis of MCL patients (all P<0.05). CONCLUSION: Circ_cgga162 is highly expressed in serum of patients MCL, which relates with the prognosis of MCL patients. Circ_cgga162 can be used as a potential prognostic marker and therapeutic target for MCL patients.


Assuntos
Linfoma de Célula do Manto , RNA Circular/genética , Humanos , Estimativa de Kaplan-Meier , Análise Multivariada , Prognóstico
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 25(3): 280-3, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18543216

RESUMO

OBJECTIVE: To investigate the association of single nucleotide polymorphisms (SNPs) in matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) with the risk of endometriosis and adenomyosis. METHODS: Genotypes of MMP-2 and TIMP-2 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method among 298 endometriosis patients, 180 adenomyosis patients and 324 matched control women. RESULTS: No significant difference was found in allele frequencies and genotype distributions of MMP-2 -1306C/T polymorphism between endometriosis patients and control women (P> 0.05). However, there were significant differences in genotype and allele distributions of MMP-2 -1306C/T polymorphism between adenomyosis patients and control women (P< 0.05). Compared with CT+TT genotypes, CC genotype significantly increases the risk of adenomyosis, with an odds ratio of 1.83 (95% CI was 1.13-2.96). No significant difference was shown in allele frequencies and genotype distributions of the MMP-2 -735C/T polymorphism among the three groups (P>0.05). MMP-2 -1306C/T and -735C/T polymorphisms displayed linkage disequilibrium (D'=0.74). There was no significant difference in haplotype distributions of the two MMP-2 SNPs among the three groups ( P> 0.05). No significant difference was found in allele frequencies of TIMP-2 -418G/C polymorphism among the three groups (P> 0.05). However, the frequency of TIMP-2 CC genotype in endometriosis patients (0.7%) was significantly lower than that in the control women (3.7%) (P< 0.05). CONCLUSION: The C allele of MMP-2 -1306C/T polymorphism did not modify the risk of developing endometriosis but significantly increase the risk of developing adenomyosis. The MMP-2 -735C/T and TIMP-2 -418G/C polymorphisms were not associated with the risk of developing endometriosis or adenomyosis.


Assuntos
Endometriose/genética , Metaloproteinase 2 da Matriz/genética , Polimorfismo de Nucleotídeo Único/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Adulto , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Desequilíbrio de Ligação/genética , Pessoa de Meia-Idade
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(9): 1797-801, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18051532

RESUMO

In the present paper, the spectrum response of Brassica Campestris L leaf to the stress of heavy metal zinc pollution was studied in three spectral rangess of the red edge position (680-740 nm), the visible spectrum (460-680 nm) and the near infrared spectrum (750-1000 nm). The results indicate that the Zn content in cabbage leaves increases and the chlorophyll level reduces with the increase in Zn concentration in soil. With the Zn content of Brassica Campestris L leaves increasing, the leaf spectral reflectivity in visible light (A1) and the range of red edge shift (S) ascends, the the leaf spectral reflectivity in the near infrared light (A2) decreases. The three indices of A1, A2 and S are fitted much linearly with the logarithm of zinc content in Brassica Campestris L leaves with the high squared regression coefficients of 0.942, 0.981 and 0.969 respectively. The regression models are reliable to estimate the zinc content in Brassica Campestris L leaves.


Assuntos
Brassica/química , Poluentes do Solo/análise , Zinco/análise , Brassica/metabolismo , Clorofila/análise , Clorofila/metabolismo , Folhas de Planta/química , Poluentes do Solo/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Zinco/metabolismo
7.
Sci Rep ; 7: 42032, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28165035

RESUMO

Leached cinnamon soil is the main agricultural soil distributed in the North China Plain. In this research, leached cinnamon soil samples were collected in the upper basin of Miyun Reservoir (northeast of Beijing, China). The BaPS method (Barometric Process Separation) was applied to measure nitrification, denitrification and respiration rates. The rates of nitrification, denitrification and respiration were 0-120.35 µg N/kg SDW h, 0-246.86 µg N/kg SDW h and 0.17-225.85 µg C/kg SDW h (Soil Dry Weight, SDW), respectively. The emission rates of CO2 and NxOy through nitrification, denitrification and respiration were 1.00-547.80 and 6.00-4850.65 µmol/h, respectively. The analysis of relationships between nitrification, denitrification and respiration rates indicated that these three microbial processes were interacted, which posed impacts on soil nitrogen availability. As indicated by the results, C:N ratio coupled with content could be taken as the indicators of content, which is usually the predominant form of N available to plants growing in soil. Results showed that content was the highest (i.e., >62.4 mg/kg) when C:N ratio was 5.30-8.40, meanwhile content was 3.71-4.39 mg/kg. Nevertheless, content was the lowest (i.e., <6.40 mg/kg) when C:N ratio was 9.2-12.10, meanwhile content was 3.41-4.35 mg/kg.

8.
Sci Rep ; 7(1): 4509, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28674443

RESUMO

In this work, Pt nanoparticles were incorporated into SBA-15 to prepare the materials for hydrogen spillover adsorption. We provide a direct modification (DM) strategy to improve the content of Pt nanoparticles inside the channels of SBA-15. In this strategy, the Pt precursor was directly incorporated into as synthesized SBA-15 by a solid-state grinding method. The subsequent calcination in air, then H2/Ar gases was conducted to obtain the resultant materials of PtAS. For the samples of PtAS, Pt nanoparticles up to 5.0 wt% have a high dispersion inside the channels of SBA-15. The size of nanoparticles is in control of 3.7 nm. Although much work so far has focused on modification of SBA-15 with Pt nanoparticles. Here, it is the first time the loading amount of Pt nanoparticles raises up to 5.0 wt%, and the location of the Pt nanoparticles is interior channels of SBA-15. We reveal that the high dispersion behaviors of Pt nanoparticles are ascribed to the nanoconfinement effects provided by as synthesized SBA-15. However, the samples derived from template free SBA-15 (PtCS) show sparsely dispersion of Pt nanoparticles with the size of 7.7 nm. We demonstrate that the PtAS samples show better hydrogen adsorption performance than PtCS.

9.
Chemosphere ; 65(3): 365-74, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16580044

RESUMO

Samples of water, suspended particulate matter (SPM) and sediment were collected from mid- and down-stream of the Yellow River. The distribution and concentration of 10 nitroaromatic compounds and polychlorinated biphenyls (PCBs) were extensively studied. The total concentration of 10 nitrobenzenes (SigmaNBs) varied from 0.269 to 9.052 microg l(-1) in water, from 2.916 to 164.4 microg kg(-1) dry weight in SPM, and from 0.954 to 14.72 microg kg(-1) dry weight in sediment. PCBs associated with the sediments, measured as the summed responses of Aroclor 1242, 1248, 1254, 1260 (in comparison to those of a standard 1:1:1:1 mixture), were found to be in the range of non-detectable to 5.98 microg kg(-1). In the samples collected, various PCB congeners showed similar distribution characteristics with congeners containing 3-5 chlorine atoms accounting for more than 96.4% of total PCB. In most of the samples, PCB concentrations occurred in the order: TetraCB > TriCB > PentaCB. Levels of SigmaNBs in the Yellow River were relatively low in comparison with values reported from other river and marine systems, and PCB levels were comparatively low. Relative to the PCBs, SigmaNBs showed significantly more difference among the various stations, presumably due to the influence of different pollution sources. No obvious correlation was observed between the pollutant concentrations and either the TOC or the grain size of the sediments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Nitrobenzenos/análise , Bifenilos Policlorados/análise , Rios/química , Poluentes Químicos da Água/análise , China , Tamanho da Partícula
10.
J Environ Sci (China) ; 18(4): 827-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17078569

RESUMO

The weekly water quality monitor data of Liuhai lakes between April 2003 and November 2004 in Beijing City were used as an example to build an artificial neural networks (ANN) model and a multi-varieties regression model respectively for predicting the fresh water algae bloom. The different predicted abilities of the two methods in Liuhai lakes were compared. A principle analysis method was first used to select the input variables of the models to avoid the phenomenon of collinearity in the data. The results showed that the input variables for the artificial neural networks were T, TP, transparency(SD), DO, chlorophyll-a (Chl-a), pH and the output variable was Chl-a. A three layer Levenberg-Marguardt feed forward learning algorithm in ANN was used to model the eutrophication process of Liuhai lakes. 20 nodes in hidden layer and 1 node of output for the ANN model had been optimized by trial and error method. A sensitivity analysis of the input variables was performed to evaluate their relative significance in determining the predicted values. The correlation coefficient between predicted value and observed value in all data and in test data were 0.717 and 0.816 respectively in the artificial neural networks. The stepwise regression method was used to simulate the linear relation between Chl-a and temperature, of which the correlation coefficient was 0.213. By comparing the results of the two models, it was found that neural network models were able to simulate non-linear behavior in the water eutrophication process of Liuhai lakes reasonably and could successfully estimate some extreme values from calibration and test data sets.


Assuntos
Clorofila/análise , Monitoramento Ambiental/métodos , Eutrofização , Modelos Biológicos , Redes Neurais de Computação , China , Clorofila/metabolismo , Clorofila A , Água Doce , Modelos Lineares , Valor Preditivo dos Testes , Análise de Componente Principal/métodos , Temperatura
11.
J Environ Sci (China) ; 18(5): 1031-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17278767

RESUMO

In order to realistically reflect the difference between regional water demand for instream flow and river ecological water demand as well as to resolve the problem that water demand may be counted repeatedly, a concept of regional water demand for minimum instream flow have been developed. The concept was used in the process of determining river functions and calculating ecological water demand for a river. The Yellow River watershed was used to validate the calculation methodology for regional water demand. Calculation results indicate that there are significant differences in water demands among the different regions. The regional water demand at the downstream of the Yellow River is the largest about 14.893 X 10(9) m(3)/a. The regional water demand of upstream, Lanzhou-Hekou section is the smallest about -5.012 x 10(9) m(3)/a. The total ecological water demand of the Yellow River Basin is 23.06 X 10(9) m(3)/a, about the 39% of surface water resources of the Yellow River Basin. That means the maximum available surface water resources should not exceed 61% in the Yellow River Basin. The regional river ecological water demands at the Lower Section of the Yellow River and Longyangxia-Lanzhou Section exceed the surface water resources produced in its region and need to be supplemented from other regions through the water rational planning of watershed water resources. These results provides technical basis for rational plan of water resources of the Yellow River Basin.


Assuntos
Ecossistema , Água , China
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(7): 1272-6, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17020038

RESUMO

The effect of Cu pollution on the Cu uptake by wheat, the characteristics of chlorophyll concentration, and the visible-near infrared spectra were studied under the condition of solution culture, and the relationships among the three indices were discussed. The results indicate that the content of Cu in TritiZnm aestivum L. increases and the concentration of chlorophyll reduces with the increase of Cu in solution. The spectral characteristics also take on the disciplinary diversification (the spectral reflectivity ascended in the visible light band and decreased in the near infrared band; the range of red edge shift decreased) with the increase of Cu in solution.


Assuntos
Cobre/metabolismo , Cobre/farmacologia , Poluentes do Solo/farmacologia , Espectrofotometria Infravermelho/métodos , Triticum/efeitos dos fármacos , Clorofila/metabolismo , Triticum/metabolismo
13.
J Environ Sci (China) ; 17(4): 676-80, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16158604

RESUMO

A case study is introduced and discussed concerning water dispute of misuse and pollution between up- and down-stream parts. The relations between water usage and local industrial structures are analyzed. Results show it is important to change industrial structures of the target region along with controlling water pollution by technical and engineering methods. Three manners of upstream-downstream cooperation are presented and discussed based on the actual conditions of Guangting Reservoir watershed. Two typical scenarios are supposed and studied along with the local plan on water resources development. The best solution for this cooperation presents a good way to help the upstream developing in a new pattern of eco-economy.


Assuntos
Abastecimento de Água , China , Água Doce
14.
Int J Clin Exp Med ; 8(10): 18391-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770443

RESUMO

BACKGROUND: Incompleteness of interlobar fissures and pleural adhesions, common in tuberculous destroyed lung (TDL), are among "technical contraindications" for video-assisted thoracoscopic surgery (VATS). The efficacy and safety of VATS in the treatment of TDL, has not yet been detailed in. OBJECTIVE: The objective of the present study is to observe the efficacy and safety of VATS in the management of TDL. METHODS: A retrospective review of anatomic lobectomy by VATS on 29 cases of TDL was performed in the Department of Thoracic Surgery of Wuhan Medical Treatment Center between October 2010 and October 2013. RESULTS: All the 29 surgeries by VATS were successfully completed. No death case was reported. Operative duration of VATS was 75~400 min, with an average of 185.4 min; intraoperative amount of bleeding ranged 50 to 2300 ml, with an average of 575.6 ml; the incidence of postoperative complication was 21.4% (6/28). Postoperative complications occurred in 6 cases, among which there were 2 cases of persistent postoperative pulmonary air leak, 2 cases of pleural effusion, one case of thoracic hemorrhage and one case of arrhythmia complicated with left heart failure. There was one patient who was converted from VATS to open thoracic surgery half-way. CONCLUSION: Our results have shown the efficacy, safety and a breakthrough in the "technical contraindications" of VATS in the management of TDL.

15.
J Environ Sci (China) ; 14(2): 234-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12046293

RESUMO

The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe-Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe-Luanhe river basin, the ecological and environmental water demand of the two lakes was calculated to be 27 x 10(8) m3. It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: (1) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Abastecimento de Água , China , Meio Ambiente , Monitoramento Ambiental , Plantas
16.
J Environ Sci (China) ; 16(1): 157-60, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14971473

RESUMO

High concentrations of air pollutants such as total suspended particulates (TSP) and sulfur dioxide (SO2) have serious impacts on nearby populations. In this paper, a survey of rural Tianjin residents' willingness-to-pay for health improvement was reported on, and the MBDC (multiple bounded discrete choice) model was adopted to study the respondents' willingness-to-pay to prevent respiratory illnesses. The results showed that the willingness-to-pay for health improvement was affected by respondents' health condition, work situation and environmental awareness, but not by personal habits, such as smoking. If person's willingness-to-pay to avoid respiratory diseases can be considered equal to the cost to personal health caused by air pollution, the total cost will reach 538 x 10(6) RMB Yuan (RMB, equal to 65 million USD) per year.


Assuntos
Poluentes Atmosféricos/economia , Poluentes Atmosféricos/intoxicação , Poluição do Ar/economia , Poluição do Ar/prevenção & controle , Saúde Pública , Adulto , China , Análise Custo-Benefício , Coleta de Dados , Monitoramento Ambiental , Humanos , Opinião Pública
17.
J Environ Sci (China) ; 16(6): 978-80, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15900732

RESUMO

The influence of the Haizhou Open Pit Mine on the atmospheric flow in nearby Fuxin City in China was analyzed with the aid of the steady-state Navier-Stokes equations. The finite element method was used to obtain numerical solutions to these equations. The results showed that the Haizhou Open Pit Coal Mine contributes to the turbulent flow in the Fuxin City and its surroundings. However, when compared with the climatic effects, the open pit mine has a relatively small impact on the atmospheric flow over Fuxin.


Assuntos
Movimentos do Ar , Carvão Mineral , Mineração , Atmosfera , China , Clima
18.
J Environ Sci (China) ; 16(6): 994-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15900736

RESUMO

One of the difficulties frequently encountered in water quality assessment is that there are many factors and they cannot be assessed according to one factor, all the effect factors associated with water quality must be used. In order to overcome this issues the projection pursuit principle is introduced into water quality assessment, and projection pursuit cluster (PPC) model is developed in this study. The PPC model makes the transition from high dimension to one-dimension. In other words, based on the PPC model, multifactor problem can be converted to one factor problem. The application of PPC model can be divided into four parts: (1) to estimate projection index function Q(a -->); (2) to find the right projection direction a -->; (3) to calculate projection characteristic value of the i th sample z(i), and (4) to draw comprehensive analysis on the basis of z(i). On the other hand, the empirical formula of cutoff radius R is developed, which is benefit for the model to be used in practice. Finally, a case study of water quality assessment is proposed in this paper. The results showed that the PPC model is reasonable, and it is more objective and less subjective in water quality assessment. It is a new method for multivariate problem comprehensive analysis.


Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Poluentes da Água/análise , Análise Multivariada , Controle de Qualidade
19.
J Environ Sci (China) ; 16(4): 646-50, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15495973

RESUMO

The applicability of a non-point source pollution model--SWAT(soil and water assessment tools) in a large river basin with high sediment runoff modulus(770 t/km2 in the Yellow River) was examined. The basic database, which includes DEM, soil and landuse map, weather data, and land management data, was established for the study area using GIS. A two-stage "Brute Force" optimization method was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997. In the process of calibration automated digital filter technique was used to separate direct runoff and base flow. The direct runoff was firstly calibrated, and the base flow, then the total runoff was matched. The sediment yield was calibrated to match well. Keeping input parameters set during the calibration process unchanged, the model was validated with 1998--1999's observed monthly flow and sediment. The evaluation coefficients for simulated and observed flow and sediment showed that SWAT was successfully applied in the study area: relative error was within 20%, coefficient of determination and Nash-Suttcliffe simulation efficiency were all equal to or above 0.70 during calibration and validation period.


Assuntos
Sistemas de Informação Geográfica , Movimentos da Água , Poluentes da Água/análise , Calibragem , China , Sedimentos Geológicos/química , Chuva , Rios
20.
J Environ Sci (China) ; 15(6): 721-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14758887

RESUMO

Based on quantum chemical calculations, TLSER model (theoretical linear solvation energy relationships) and atomic charge approach were applied to model the partition properties(water solubility and octanol/water partition coefficient) of 96 aromatic sulfur-containing carboxylates, including phenylthio, phenylsulfinyl and phenylsulfonyl carboxylates. In comparison with TLSER models, the atomic charge models are more accurate and reliable to predict the partition properties of the kind of compounds. For the atomic charge models, the molecular descriptors are molecular surface area (S), molecular shape (O), weight( MW), net charges on carboxyl group (QOC), net charges of nitrogen atoms (QN), and the most negative atomic charge (q-) of the solute molecule. For water solubility (log SW) and octanol/water partition coefficient (log KOW), the correction coefficients r2adj (adjusted for degrees of freedom) are 0.936 and 0.938, and the standard deviations are 0.364 and 0.223, respectively.


Assuntos
Hidrocarbonetos Aromáticos/química , Modelos Químicos , Relação Quantitativa Estrutura-Atividade , Compostos de Enxofre/química , Octanóis/química , Análise de Regressão , Solubilidade , Água/química
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