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Application of a novel detection approach based on non-dispersive infrared theory to the in-situ analysis on indicator gases from underground coal fire

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Journal of Central South University 2022年第6期29卷 1840-1855页

作者： TIAN Fu-chao LIANG Yun-tao ZHU Hong-qing CHEN Ming-yi WANG Jin-cheng College of Emergency Management and Safety Engineering China University of Mining and Technology(Beijing)Beijing 100083China State Key Laboratory of Coal Mine Safety Technology China Coal Technology&Engineering Group Shenyang Research InstituteShenyang 113122China Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China Key Laboratory of Roads and Railway Engineering Safety Control(Shijiazhuang Tiedao University) Ministry of EducationShijiazhuang 050043China

Coal mine fires,which can cause heavy casualties,environmental damages and a waste of coal resources,have become a worldwide *** at overcoming the drawbacks,such as a low analysis efficiency,poor stability and large monitoring error,of the existing underground coal fire monitoring technology,a novel monitoring system based on non-dispersive infrared(NDIR)spectroscopy is *** this study,first,the measurement principle of NDIR sensor,the gas concentration calculation and its temperature compensation algorithms were ***,taking CO and CH_(4) as examples,the liner correlation coefficients of absorbance and the temperature correction factors of the two indicator gases were calculated,and then the errors of concentration measurement for CO,CO_(2),CH_(4) and C_(2)H_(4) were further *** results disclose that the designed NDIR sensors can satisfy the requirements of industrial standards for monitoring the indicator gases for coal fire *** the established NDIR-based monitoring system,the NDIRbased spectrum analyzer and its auxiliary equipment boast intrinsically safe and explosion-proof performances and can achieve real-time and in-situ detection of indicator gases when installed close to the coal fire risk area ***,a field application of the NDIR-based monitoring system in a coal mine shows that the NDIR-based spectrum analyzer has a permissible difference from the chromatography in measuring the concentrations of various indicator ***,the advantages of high accuracy,quick analysis and excellent security of the NDIR-based monitoring system have promoted its application in many coal mines.

关键词： indicator gas coal spontaneous combustion infrared spectrometry bundle tube monitoring intrinsically safe

A Trojan horse biomimetic delivery system using mesenchymal stem cells for HIF-1α siRNA-loaded nanoparticles on retinal pigment epithelial cells under hypoxia environment

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International Journal of Ophthalmology(English edition) 2022年第11期15卷 1743-1751页

作者： Lei Zhang Jie-Jing Yan Hai-Yan Wang Mu-Qiong Li Xi-Xi Wang Li Fan Yu-Sheng Wang Shaanxi Eye Hospital Xi'an People's Hospital(Xi'an Fourth Hospital)Xi'an 710004Shaanxi ProvinceChina Department of Ophthalmology Xijing HospitalXi'an 710032Shaanxi ProvinceChina Ophthalmology Department Xi'an No.1 Hospitalthe First Affiliated Hospital of Northwest UniversityXi'an 710002Shaanxi ProvinceChina Department of Pharmaceutical Chemistry and analysis School of Pharmacy Air Force Medical University Xi'an 710032Shaanxi ProvinceChina Department of Mathematics and Statistics University of Arkansas at Little RockLittle RockAR 72204USA

AIM: To demonstrate the feasibility of mesenchymal stem cell(MSC)-mediated nano drug delivery, which was characterized by the “Trojan horse”-like transport of hypoxiainducible factor-1α small interfering RNA(HIF-1α si RNA) between MSCs and retinal pigment epithelial cells(RPE) under hypoxia ***: Plasmid and lentivirus targeting the human HIF-1α gene were designed and constructed. HIF-1α si RNA was encapsulated into poly(lactic-co-glycolic acid) nanoparticles(PLGA-NPs) through the water-in-oil-in-water(w/o/w) multiple emulsion technique. The effect of PLGANPs uptake on the expression of HIF-1α m RNA was tested in RPE cells by real-time quantitative polymerase chain reaction(q PCR) and additional transfected conditions were used as control, including lentivirus group, nude plasmid group and blank PLGA group. MSCs were transfected with the NPs and the transfection efficacy was evaluated by flow cytometry. Transwell co-culture system of transfected MSCs and RPE cells was constructed under hypoxia environment. The effects of MSC-loaded HIF-1α si RNA PLGA-NPs on proliferation, apoptosis, and migration of RPE cells were then evaluated. The effect of transfected MSCs on HIF-1α expression of RPE cells was analyzed by using q PCR at the time points 24h, 3d, and ***: The average diameter of PLGA-NPs loaded with HIF si RNA was 314.1 nm and the zeta potential was-0.36 m V. The transfection efficiency of PLGA-NPs was 67.3%±5.2% into MSCs by using flow cytometry. Compared with the lentivirus group, the PLGA-NPs loaded with HIF-1α si RNA can effectively reduce the expression of HIF-1α m RNA up to 7d in RPE(0.63±0.05 at 7d, P<0.001). In the Transwell co-culture system of transfected MSCs and RPE, the abilities of proliferation(2.34±0.17, 2.40±0.28, 2.47±0.24 at 48h, F=0.23, P=0.80), apoptosis(14.83%±2.43%, 12.94%±2.19%, 12.39%±3.21%;F=0.70, P=0.53) and migration(124.5±7.78, 119.5±5.32, 130±9.89, F=1.33, P=0.33) of the RPE cells had no differences between MSClo

关键词： hypoxia mesenchymal stem cells poly(lactic-co-glycolic acid)nanoparticles hypoxia-inducible factor-1α retinal pigment epithelial cells

Bench-top aqueous two-phase extraction of isolated individual single-walled carbon nanotubes

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Nano research 2015年第5期8卷 1755-1769页

作者： Navaneetha K. Subbaiyan A. Nicholas G. Parra-Vasquezt Sofie Cambre Miguel A. Santiago Cordoba Sibel Ebru Yalcin Christopher E. Hamilton Nathan H. Mack Jeffrey L. Blackburn Stephen K. Doorn Juan G. Duque Chemistry Division Physical Chemistry and Applied Spectroscopy Group (C-PCS) Center for Integrated Nanotechnologies (CINT) and Materials Science & Technology Division (MST-7) Los Alamos National Laboratory Los Alamos New Mexico 87544 USA Experimental Condensed Matter Physics Laboratory University of Antwerp Antwerp B-2610 Belgium National Renewable Energy Laboratory Golden Colorado 80401 USA

Isolation and purification of single-walled carbon nanotubes （SWCNTs） are prerequisites for their implementation in various applications. In this work, we present a fast （-5 min）, low-cost, and easily scalable bench-top approach to the extraction of high-quality isolated SWCNTs from bundles and impurities in an aqueous dispersion. The extraction procedure, based on aqueous two-phase （ATP） separation, is widely applicable to any SWCNT source （tested on samples up to 1.7 nm in diameter） and independent of defect density, purity, diameter, and length. The extracted dispersions demonstrate that the removal of large aggregates, small bundles, and impurities is comparable to that by density gradient ultracentrifugation, but without the need for high-end instrumentation. Raman and fluorescence-excitation spectroscopy, single-nanotube fluorescence imaging, atomic force and transmission electron microscopy, and thermogravimetric analysis all confirm the high purity of the isolated SWCNTs. By predispersing the SWCNTs without sonication （only gentle stirring）, full-length, pristine SWCNTs can be isolated （tested up to 20 μm）. Hence, this simple ATP method will find immediate application in the generation of SWCNT materials for all levels of nanotube research and applications, from fundamental studies to high-performance devices.

关键词： carbon nanotubes aqueous two-phase (ATP)separation aggregate removal isolation sorting

UV irradiation-H2O2 system as an effective combined depolymerization technique to produce oligosaccharides from chitosan

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Bio-Design and Manufacturing 2018年第1期1卷 62-68页

作者： Seyed Ahmad Ayati Najafabadi Hengameh Honarkar Majid Moghadam Valiollah Mirkhani Mohammadreza Tahriri Lobat Tayebi Biomaterials group Faculty of Biomedical Engineering Amirkabir University of Technology Tehran Iran Polyurethane and Advanced polymers Faculty of Science Iran Polymer and Petrochemical Institute Tehran Iran Catalysis Divisions Department of Chemistry University of Isfahan Isfahan Iran Marquette University School of Dentistry Milwaukee WI 53233 USA Department of Engineering Science University of Oxford Oxford OX13PJ UK

UV irradiation hydrogen peroxide （H202） system is used as an effective, easy and low-cost combined depolymerization technique to produce oligosaccharides from chitosan. UV-Vis spectroscopic studies explained that with increasing treatment time, the absorption of the depolymerized chitosan solution has increased, indicating the increase in the carbonyl and amino groups in their structure. Fourier transform infrared spectroscopy and nuclear magnetic resonance （1H NMR） analysis showed that the 1,4-β-D-glucoside linkages of chitosan are degraded without important changes in chemical structure of decomposed samples. X-ray diffraction patterns verified the polymerization of chitosan to produce oligomers, changing in structure from crystalline to amorphous. Viscosity-average molecular weight measurements of fragmented chitosan samples and MarkHouwink equation are used to demonstrate the efficiency of this depolymerization method. Finally, the obtained results ascertained that this combined method could produce water soluble chitosan with significant efficiency and no essential change in its chemical *** irradiation hydrogen peroxide （H202） system is used as an effective, easy and low-cost combined depolymerization technique to produce oligosaccharides from chitosan. UV-Vis spectroscopic studies explained that with increasing treatment time, the absorption of the depolymerized chitosan solution has increased, indicating the increase in the carbonyl and amino groups in their structure. Fourier transform infrared spectroscopy and nuclear magnetic resonance （1H NMR） analysis showed that the 1,4-β-D-glucoside linkages of chitosan are degraded without important changes in chemical structure of decomposed samples. X-ray diffraction patterns verified the polymerization of chitosan to produce oligomers, changing in structure from crystalline to amorphous. Viscosity-average molecular weight measurements of fragmented chitosan samples and MarkHouwink equation are used to dem

关键词： Chitosan Depolymerization Ultraviolet irradiation Hydrogen peroxide Oligosaccharides

analysis on Dam-Breaking Mode of Tangjiashan Barrier Dam in Beichuan County

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Journal of Mountain Science 2011年第2期8卷 354-362页

作者： HU Xiewen LUO Gang LV Xiaoping HUANG Runqiu SHI Yubin Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Chengdu 610031 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Aseismic Engineering Technology Key Laboratory of Sichuan Province Southwest Jiaotong UniversityChengdu 610031 China Chengdu Hydroelectric Investigation and Design Institute China Hydropower Consulting Group Chengdu 610072 China

Tangjiashan landslide is a typical high-speed consequent landslide of medium-steep dip angle. This landslide triggered by earthquake took place in about semi-minute. The relative sliding displacement is 900 meters, so average sliding speed is about 30 meters per second. The longitudinal length of barrier dam which is formed by high-speed landslide along river is 803.4 meters; and maximum width crossing river is 611.8 meters. And its volume is estimated about 20.37 million steres. Through detailed geological investigation of the barrier dam, together with early geological information before earthquake, geological structures of the barrier dam and its stability of upstream and downstream slopes are studied when water level reaches different elevations in condition of continual after shocks with seismic intensity of 7 or 8 Richter scale. On this basis, dam-breaking mode of barrier dam is discussed deeply. Thereby, analytic results provide significant guidance and advices to front headquarters of Tangjiashan barrier dam, so that some proper engineering measures can be implemented and flood discharge can be carried out well.

关键词： Tangjiashan Barrier Dam High-speed landslide Blocking river Dam-breaking

Association oftransforming growth factor-β1 gene variants with risk of coal workers'pneumoconiosis

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The Journal of Biomedical research 2010年第4期24卷 270-276页

作者： Haiyang Qian Zhifang Song Meilin Wang Xiaomin Jia Aiping Li Ye Yang Lianlian Shen Shasha Wang Chunhui Ni Jianwei Zhou Department of Occupational Medicine and Environmental Health School of Public Health Nanjing Medical University Nanjing 210029 Jiangsu Province China Department of Occupational Health General Hospital of Xuzhou Mining Business Group Co. Ltd. Xuzhou 221006 Jiangsu Province China

Objective： The aim of this case-control study was to explore whether five tagging single nucleotide poly- morphisms （tSNPs） within the transforming growth factor-ill （TGF-fll） gene were involved in manifestation of inflammatory and fibrotic processes associated with coal workers pneumoconiosis （CWP）. Methods： The study included 508 CWP patients and 526 controls who were underground coal miners from Xuzhou Mining Business group. Five tSNPs were selected from the HapMap and detected by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method. Results： The single SNP analysis showed that the genotype frequencies of SNP2 （rs1800470, ＋869T/C, extron 1） and SNP5 （rs11466345, intron 5） in CWP cases were significantly different from those in controls. Multivariate logistic regression analysis revealed that SNP2 （rs1800470） CC genotype was associated with decreased risk of CWP （OR = 0.50, 95% CI = 0.32-0.78）, which was evident among subgroups of those never smoke （OR = 0.40, 95%CI = 0.24-0.66）, cases with stage Ⅱ（OR = 0.41, 95%CI = 0.22-0.76） and exposure period （〈 28 y： OR = 0.54, 95%CI = 0.31-0.95; ≥ 28 y： OR = 0.52, 95%CI = 0.32-0.96）. However, the SNP5 （rs11466345） GG genotype was associated with an increased risk of CWP （OR = 2.5, 95%CI = 1.36-4.57）, and further stratification analysis showed that the risk of CWP was increased in both smoking and nonsmoking groups, shorter and longer exposure groups, while the risk of CWP was only increased in patients with stage I and Ⅱ. Conclusion： This study suggests that TGF-β1 polymorphisms may contribute to susceptibility of CWP.

关键词： coal worker pneumoconiosis molecular epidemiology polymorphism transforming growthfactor-β1

Pathway analysis provides insight into the genetic susceptibility to hepatocellular carcinoma and insight into immuno-therapy treatment response

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Hepatoma research 2018年第6期4卷 41-50页

作者： Yih-Kuang Lu Jacob Morris Brill Ardesher Aghili Kenneth Howard Buetow computational Sciences and Informatics Complex Adaptive SystemsArizona State UniversityTempeAZ 85287USA Center for Evolution and Medicine Arizona State UniversityTempeAZ 85287USA School of Life Sciences Arizona State UniversityTempeAZ 85287USA

Clear evidence exists for genetic susceptibility to hepatocellular carcinoma (HCC). Genome-wide association studies have identified multiple candidate susceptibility loci. These loci suggest that genetic variation in the immune system may underpin HCC susceptibility. Genes for the antigen processing and presentation pathway have been observed to be significantly enriched across studies and the pathway is identified directly through genome-wide studies of variation using pathway methods. Detailed analysis of the pathway indicates both variation in the antigen presenting loci and in the antigen processing are different in cases in controls. Pathway analysis at the transcriptional level also shows difference between normal liver and liver in individuals with HCC. Assessing differences in the pathway may prove important in improving immune therapy for HCC and in identifying responders for immune checkpoint therapy.

关键词： Hepatocellular carcinoma genetic susceptibility genome-wide association study pathway analysis antigen presentation and processing immune checkpoint therapy

Hydrological Modeling of Upper OumErRabia Basin (Morocco), Comparative Study of the Event-Based and Continuous-Process HEC-HMS Model Methods

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computational Water, Energy, and Environmental Engineering 2020年第4期9卷 159-184页

作者： Mohamed Msaddek George Kimbowa Abdelkader El Garouani Faculty of Sciences and Techniques Sidi Mohamed Ben Abdellah University Route Imouzzer Fez Morocco Pan African University Institute of Water and Energy Sciences (Including Climate Change) (PAUWES) C/o University AbouBekrBelkaid Tlemcen Algeria Faculty of Engineering Busitema University Tororo Uganda Wageningen University and research Water Resources Management Group Wageningen Netherlands

Human population growth and land-use changes raise demand and competition for water resources. The Upper OumErRabia River Basin is experiencing high rangeland and matorral conversion to irrigated agricultural land expansion. Given Morocco’s per capita water availability, River-basin hydrologic modelling could potentially bring together agricultural, water resources and conservation objectives. However, not everywhere have hydrological models considered events and continuous assessment of climatic data. In this study, HEC-HMS modelling approach is used to explore the event-based and continuous-process simulation of land-use and land cover change (LULCC) impact on water balance. The use of HEC-GeoHMS facilitated the digital data processing for coupling with the model. The basin’s physical characteristics and the hydro-climatic data helped to generate a geospatial database for HEC-HMS model. We analyzed baseline and future scenario changes for the 1980-2016 period using the SCS Curve-Number and the Soil Moisture Accounting (SMA) loss methods. SMA was coupled with the Hargreaves evapotranspiration method. Model calibration focused on reproducing observed basin runoff hydrograph. To evaluate the model performance for both calibration and validation, the Coefficient of determination (R2), Nash-Sutcliffe efficiency (NSE), Root Mean Square Error (RSR)

关键词： HEC-HMS Model Land-Use and Land Cover Change Soil Moisture Accounting (SMA) Upper OumErRabia Watershed

Effect of Bromocriptine on Insulin Resistance in Patients with PCO

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Open Journal of Endocrine and Metabolic Diseases 2014年第12期4卷 253-257页

作者： Zivar Shirinpour Bahman Ghaderian Homeira Rashidi Armaghan Moravej Aleali Seyed Peyman Payami Health research Institute Diabetes Research Center Ahvaz Jundishapur University of Medical Sciences Ahvaz Iran

Introduction: Poly cystic ovary (PCO) is one of the most common endocrine disorders in women. All patients with PCO are at risk of insulin resistance, IFG and diabetes. Recently, bromocriptine is used in treatment of diabetes mellitus type II to improve insulin resistance. Objective: The aim of this study is the evaluation of bromocriptine on insulin resistance in PCO people. Patients and Methods: In this single-blind controlled clinical trial with placebo, 44 patients with PCO referring to endocrinology clinic were evaluated. Inclusion criteria were BMI > 25 kg/m2 and diagnosed PCO patients according to Rotterdam criteria and rule out other causes. Blood samples were obtained for FBS, Fasting Insulin, Prolactin, TSH and 17(OH)P. They divided two groups: Case group was given bromocriptine 2.5 mg daily and placebo was given to control group. Patients were treated for 8 days and in day 9th blood sample was obtained for FBS, Fasting insulin, HOMA-IR index. Mann-Whitney method is used for mean comparison. Results: Data analysis using showed in pre diabetes range, mean changes of FBS, insulin level and IR in groups 1 and 2 had significant differences(P = 0.004), but no significant different was found in FBS group with BMI 2, no significant differences were found in changes in FBS group with BMI ≥ 30 kg/m2, no significant differences were found in changes in insulin level and IR (P = 0.69, 0.089 respectively). Mean systolic blood pressure changes in group 1 and 2 in FBS > 100 mg/dl with (P = 0.036) were significant, but no significant difference showed in mean change of diastolic blood pressure in FBS > 100 mg/dl (P = 0.99). In FBS groups 1 and 2 (P = 0.1). Conclusion: Our study showed, even in the short-term consumption, br

关键词： Bromocriptine Insulin Resistance PCO FBS