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Cerebroprotection with recombinant neuroglobin plasmid in a rat model of focal cerebral ischemia

Neural Regeneration Research 2010年第1期5卷 52-57页

作者： ji Zhu Wenyuan tang Department of Neurosurgery First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China

BACKGROUND： Adenovirus has been used to develop neuroglobin （Ngb） vectors. Although transfection efficiency is high, induced gene mutation, cytotoxicity, inflammation, and low exogenous gene content have limited its application. OBJECTIVE： To observe the effects of recombinant Ngb plasmid in a rat model of focal cerebral ischemia. DESIGN, TIME AND SETTING： Genetically engineered, randomized, controlled, animal experiment was performed at the Laboratory of Chongqing Medical University from May 2006 and January 2007. MATERIALS： 2, 3, 5-triphenyltetrazolium chloride was purchased from Shanghai Sangon Biological Engineering Technology and Services. Rabbit anti-rat Bcl-2 polyclonal antibody, rabbit anti-rat β-actin monoclonal antibody, and FITC-labeled goat anti-rabbit IgG were purchased from Sigma, USA. TUNEL apoptosis kit was purchased from Roche, Germany. METHODS： A total of 54 male, adult, Wistar rats were randomly assigned to 3 groups （n=18）： normal saline, plasmid control, and recombinant Ngb （pCDNA3.1 （＋）/Ngb）. Normal saline, plasmid pCDNA3.1 （＋）, and recombinant plasmid pCDNA3.1 （＋）/Ngb were separately injected into two sites in the rat cerebral cortex, and models of focal ischemia were established by occlusion of the right middle cerebral artery after 24 hours. MAIN OUTCOME MEASURES： Local ischemic damage was detected by 2, 3, 5- triphenyltetrazolium chloride staining, apoptosis in the penumbra was confirmed using the TUNEL method, and Bcl-2 protein expression in the penumbra was determined by indirect immunofluorescent staining and Western blot analysis. RESULTS： Compared with the normal saline and plasmid control groups, cerebral infarction size and the number of apoptotic cells in the pCDNA3.1 （＋）/Ngb group were significantly reduced （P 〈 0.01）. The percentage of Bcl-2-positive cells in the penumbra of the pCDNA3.1 （＋）/Ngb group was significantly increased （P 〈 0.01）. The relative expression level of Bcl-2 protein was increased by 40%-50%. CONCLUSION： Recombi

关键词： neuroglobin cerebral ischemia cell apoptosis ischemic penumbra Bcl-2

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INFLUENCE OF MOLECULAR STRUCTURES OF SECONDARY AMINE TERMINATED POLY(ESTER-AMINE)S ON THE CURING PERFORMANCE WITH EPOXY RESIN

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Chinese Journal of Polymer Science 2007年第6期25卷 545-553页

作者： Li-ming tang ji Feng Yu Wang Advanced Materials Laboratory Department of Chemical Engineering Tsinghua University Beijing 100084 China

Five secondary amine terminated poly（ester-amine）s （defined as PEA） with controlled molecular structures were synthesized through reacting excessive piperazine with phthalicdiglycol diacrylate （PDDA） and 1,1,1-trimethylolpropane triacrylate （TMPTA） at a constant secondary amine/acrylate group ratio of 1.5/1 and at different PDDA/TMPTA molar ratios. Both IR and ^1H-NMR spectra indicated that all acrylate groups were consumed in the reaction, based on which the structural parameters were calculated from the ^1H-NMR spectra. With decreasing PDDA/TMPTA ratio, the content of secondary amine, degree of branching, molecular weight, Tg and Td increased accordingly. These polymers were further used as both crosslinkers and flexibilizers for a linear epoxy resin E51 to form cured films under ambient condition. The gel content, relative hardness and Tg of the resulting films increased as PEA molecules changed from linear to highly branching structures. Due to the flexibility of PEA molecules, all the films possessed excellent mechanical performance.

关键词： Poly(ester-amine) Molecular structure Epoxy resin Cured film.

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Identifying and localizing of seismogenic electromagnetic anomalies from data observed by permanent MT stations

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Science China Earth Sciences 2024年第5期67卷 1698-1713页

作者： Bing HAN Wenbao HU Guoze ZHAO ji tang State Key Laboratory of Earthquake Dynamics Institute of GeologyBeijing 100029China Key Laboratory of Exploration Technologies for Oil and Gas Resources of Ministry of Education Yangtze UniversityWuhan 430100China

In this research, an arbitrarily oriented electric dipole at subsurface is used to simulate Seismogenic Electromagnetic(SEM) radiation emanating from a seismic zone during its gestation phase. Analytical synthesis of responses at the Lijiang magnetotelluric(MT) station has revealed that SEM radiation could induce identifiable anomalies in the electromagnetic(EM)spectrum, apparent resistivity and phase within specific frequency bands. Background variations were extracted from long-term observation data of Dali and Lijiang MT stations, enabling the identification of SEM anomalies related to the Yunlong and Yangbi earthquakes. Multiple parameters of dipole sources at subsurface were obtained by applying the Differential Ant Colony Optimization(DACO) algorithm to anomalous data of two stations with multi-frequencies and various response functions. The spatial distribution of these predicted dipoles is predominantly clustered in or around the seismogenic area, with their azimuthal orientation aligning towards the seismogenic fault in general. This study has demonstrated the potential of using subsurface electric dipole simulations for SEM radiation analysis, offering a feasible approach for the prediction and understanding of seismogenic zones.

关键词： MT responses Identifying SEM anomaly Vector electric dipole responses Localizing SEM sources by inversion

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IN SITU ETHYLENE COPOLYMERIZATION WITH AN OLEFIN-TYPE MONOMER FOR ONE-POT SYNTHESIS OF POLYETHYLENE TETHERED ON MULTI-WALLED CARBON NANOTUBES

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Chinese Journal of Polymer Science 2013年第10期31卷 1329-1333页

作者： ji-jun tang Shi-yun Li Yan-hui Wang Tao tang Department of Materials Science and Engineering Jiangsu University of Science and Technology State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

A one-pot procedure for the synthesis of polyethylene tethered on multi-walled carbon nanotubes by in situ ethylene copolymerization with an olefin-type comonomer, tr-alkene functionalized multi-walled carbon nanotubes （MW- CH = CH2） is reported. The covalent linkage between polyethylene and multi-walled carbon nanotubes is demonstrated. The MWCNTs are chemically oxidized first by a strong oxidizing agent and then functionalized with chlorocarbonyl groups （MW--COC1） via reacting with thionyl chloride. The MW--CH=CH2 are obtained by esterification of co-undecylenyl alcohol with MW--COCI. The MW--CH = CH2 may serve as olefin-type comonomers to fiLrther synthesize core-shell structured copolymers with a multi-walled carbon nanotubes core grafted with side chains of polyethylene via rac-（en）（THInd）2ZrC12 copolymerization catalyst. The core-shell structured nanocomposites were characterized by means of 1H-NMR, SEM, FTIR and TGA. The results confirmed the formation of polyethylene chains growing from the surface of multi-walled carbon nanotubes.

关键词： Carbon nanotubes Copolymerization Polyethylene Nanocomposite.

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Microscale crack propagation in shale samples using focused ion beam scanning electron microscopy and three-dimensional numerical modeling

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Petroleum Science 2023年第3期20卷 1488-1512页

作者： Xin Liu Si-Wei Meng Zheng-Zhao Liang Chun'an tang jia-Ping Tao ji-Zhou tang aState Key Laboratory of Coastal and Ofshore Engineering Dalian University of TechnologyDalianLiaoning11624China Research Institute of Petroleum Exploration Development China National Petroleum CorporationBeijing100083China State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China

Reliable prediction of the shale fracturing process is a challenging problem in exploiting deep shale oil and gas *** fracture networks need to be artificially created to employ deep shale oil and gas *** distributed minerals and heterogeneities in shales significantly affect mechanical properties and fracturing behaviors in oil and gas *** the actual microstructure and associated heterogeneities in shales constitutes a significant *** RFPA3D(rock failure process analysis parallel computing program)-based modeling approach is a promising numerical technique due to its unique capability to simulate the fracturing behavior of *** improve traditional numerical technology and study crack propagation in shale on the microscopic scale,a combination of high-precision internal structure detection technology with the RFPA^(3D) numerical simulation method was developed to construct a real mineral structure-based modeling ***,an improved digital image processing technique was developed to incorporate actual shale microstructures(focused ion beam scanning electron microscopy was used to capture shale microstructure images that reflect the distri-butions of different minerals)into the numerical ***,the effect of mineral inhomogeneity was considered by integrating the mineral statistical model obtained from the mineral nanoindentation experiments into the numerical *** simulating a shale numerical model in which pyrite particles are wrapped by organic matter,the effects of shale microstructure and applied stress state on microcrack behavior and mechanical properties were investigated and *** this study,the effect of pyrite particles on fracture propagation was systematically analyzed and summarized for the first *** results indicate that the distribution of minerals and initial defects dominated the fracture evolution and the failure *** are generally initiated and propagate

关键词： FIB-SEM Digital imageprocessing Realistic microstructure 3D digital shale fracture process simulation Pyrite

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Predicting model on ultimate compressive strength of Al_2O_3-ZrO_2 ceramic foam filter based on BP neural network

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China Foundry 2011年第3期8卷 286-289页

作者： Yu jingyuan Li Qiang tang ji Sun Xudong College of Materials Science and Engineering Liaoning University of Technology Jinzhou 121001 China Key Laboratory of New Materials in Automobile of Liaoning Province Liaoning University of Technology Jinzhou 121001 China Shenyang Research Institute of Foundry Shenyang 110022 China Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110004 China

In present study, BP neural network model was proposed for the prediction of ultimate compressive strength of Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The inputs of the BP neural network model were the applied load on the epispastic polystyrene template （F）, centrifugal acceleration （v） and sintering temperature （T）, while the only output was the ultimate compressive strength （（7）. According to the registered BP model, the effects of F, v, T on 0 were analyzed. The predicted results agree with the actual data within reasonable experimental error, indicating that the BP model is practically a very useful tool in property prediction and process parameter design of the Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting.

关键词： Al2O3-ZrO2 ceramic foam centrifugal slip casting BP neural network process parameters ultimate compressive strength

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Application conditions for ester cured alkaline phenolic resin sand

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China Foundry 2016年第4期13卷 231-237页

作者： Ren-he Huang Bao-ping Zhang Yao-ji tang Shandong University of Science and Technology Qingdao 266510China

Five organic esters with different curing speeds:propylene carbonate(***-speed ester A);1,4-butyrolactone;glycerol triacetate(***-speed ester B);glycerol diacetate;dibasic ester(DBE)(*** ester C),were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic *** relationships between the curing performances of the resin(including pH value,gel pH value,gel time of resin solution,heat release rate of the curing reaction and tensile strength of the resin sand)and the amount of added organic ester and curing temperature were *** results indicated the following:(1)The optimal added amount of organic ester should be 25 wt.%-30 wt.%of alkaline phenolic resin and it must be above 20 wt.%-50 wt.%of the organic ester hydrolysis amount.(2)High-speed ester A(propylene carbonate)has a higher curing speed than 1,4-butyrolactone,and they were both used as high-speed *** diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand;glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin.(3)High-speed ester A,medium-speed ester B(glycerol triacetate)and low-speed ester C(dibasic ester,i.e.,DBE)should be used below 15°C,35°C and 50°C,***-speed ester A or lowspeed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand.(4)There should be a suitable solid content(generally 45 wt.%-65 wt.%of resin),alkali content(generally 10 wt.%-15 wt.%of resin)and viscosity of alkaline phenolic resin(generally 50-300 mPa·s)in the preparation of alkaline phenolic ***,the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

关键词： organic ester alkaline phenolic resin application conditions

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Modeling and analysis of porosity and compressive strength of gradient Al_2O_3-ZrO_2 ceramic lter using BP neural network

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China Foundry 2013年第4期10卷 227-231页

作者： Li Qiang Zhang Fengfeng Yu jingyuan tang ji School of Materials Science and Engineering Liaoning University of Technology Shenyang Research Institute of Foundry

BP neural network was used in this study to model the porosity and the compressive strength of a gradient Al2Q-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The influences of the load applied on the epispastic polystyrene template （F）, the centrifugal acceleration （V） and sintering temperature （T） on the porosity （P） and compressive strength （a） of the sintered products were studied by using the registered three-layer BP model. The accuracy of the model was verified by comparing the BP model predicted results with the experimental ones. Results show that the model prediction agrees with the experimental data within a reasonable experimental error, indicating that the three-layer BP network based modeling is effective in predicting both the properties and processing parameters in designing the gradient Al203-ZrO2 ceramic foam filter. The prediction results show that the porosity percentage increases and compressive strength decreases with an increase in the applied load on epispastic polystyrene template. As for the influence of sintering temperature, the porosity percentage decreases monotonically with an increase in sintering temperature, yet the compressive strength first increases and then decreases slightly in a given temperature range. Furthermore, the porosity percentage changes little but the compressive strength first increases and then decreases when the centrifugal acceleration increases.

关键词： gradient Al203-ZrO2 ceramic foams centrifugal process parameters BP neural network porosity compressive strength

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Danshen protects endothelial progenitor cells from oxidized low-density lipoprotein induced impairment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 618-626页

作者： Kang-ting ji Jun-de CHAI Cheng XING jin-liang NAN Peng-lin YANG ji-fei tang Department of Cardiology the Second Affiliated Hospital Wenzhou Medical College Wenzhou 325027 China

In this study, we examined the protective effects of Danshen both on endothelial progenitor cells （EPCs） in patients with hypercholesterolemia and on in-vitro EPCs of healthy volunteers. In the clinical study, we randomly divided 24 subjects with hypercholesterolemia into two groups （the control group and the Danshen-treated group）. At the end of two weeks of treatment, the EPC cellular functions of both groups were tested. The results indicated that, compared to the control group, EPCs in the Danshen-treated group showed significantly better cellular functions, which was manifested in the cloning number, the proliferation capacity, the number of EPC adhesions, and cell migration. In the subsequent in-vitro experiments, EPCs were treated with vehicle, oxidized low-density lipoprotein （Ox-LDL, 100 pg/ml）, or Ox-LDL （100 pg/ml） plus different concentrations of Danshen （Danshensu 2, 10, or 50 pg/ml, respectively） for 24 h. The results showed that Danshen treatments can prevent the detrimental effects of Ox-LDL on EPC cellular functions measured by proliferation capacity （0.24±0.08, 0.37±0.11, 0.30±0.04 vs. 0.13±0.02, P〈0.05, P〈0.01, and P〈0.01, respectively）, and adhesion ability （63.00_±11.60, 70.00±10.80, 85.50±11.41 vs. 40.50±6.85, all P〈0.01）. Compared to the group treated with Ox-LDL alone, Danshen treatment significantly decreased the lipid peroxidation end product malondialdehyde （MDA） [（4.34±0.54）, （3.98±0.47）, （3.46±0.31） vs. （5.57-±0.64） nmol/ml, all P〈0.01], increased the production of superoxide dismutase （SOD） [（29.74±0.71）, （31.09±0.83）, （30.41±0.65） vs. （14.76±3.99） U/ml, all P〈0.01], and lowered the expression of interleukin-6 （IL-6） [（24.62±7.69）, （27.04±3.14）, （33.38±18.86） vs. （230.67±33.53） pg/ml, all P〈0.01] and tumor necrosis factor-α （TNF-α） [（41.72±6.10）, （17.02±6.82）, （3.73±2.26） vs. （228.71±41.53） pg/ml, all P〈0.01] in Ox-LDL treated EPCs. These results suggest that Danshen may exert a protective effect through its antioxidant and anti-inflamm

关键词： Danshen Endothelial progenitor cells Oxidized low-density lipoprotein Hypercholesterolemia

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Numerical study of hydraulic fracturing in the sectorial well-factory considering well interference and stress shadowing

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Petroleum Science 2023年第6期20卷 3567-3581页

作者： Yu-Hao Liu jin-Tao Zhang jie Bai Feng-Shou Zhang ji-Zhou tang Key Laboratory of Geotechnical&Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Southwest Oil&Gas Field Company PetroChinaChengdu610017SichuanChina Oil and Gas Technology Research Institute PetroChina Changqing Oilfield CompanyXi’an710021ShaanxiChina National Key Laboratory of Marine Geology Tongji UniversityShanghai200092China School of Ocean and Earth Science Tongji UniversityShanghai200092China

In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature of a sectorial well-factory is the deviation of the well from the minimum horizontal principal stress, resulting in hydraulic fracture deflection after the initiation, along with possible well interference (i.e., fracture hit) and fracture coalescence in the oblique wells. Four indexes describing well deflection are then proposed according to fracture morphology. Several fracturing designs, including stage arrangement, fracturing sequences, and fracturing techniques are applied to study the feasibility of the sectorial well-factory design. The results show that the “gradual” or “sparse” stage arrangement, large injection rate, and simultaneous multifracture treatment can help to optimize the fracture morphology and stimulation design. However, the subsequent stress shadowing effect usually adversely affects the fracturing of adjacent wells. With a small initial horizontal stress difference, large injection rate and staggered stage arrangement can achieve ideal stimulation performance. Our results can provide a guidance for optimizing stimulation design in unconventional well-factory while taking into account environmental protection.

关键词： Hydraulic fracturing Sectorial well-factory Fracture deflection Well interference Stress shadowing

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