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Stimulatory Effect of Tithonya diversifolia-by Products on Plantain Banana Vivoplants in Nursery (A Review)
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作者 Cécile Annie Ewané Arouna Meshuneke +9 位作者 Gaston Elock Mbang Fabrice Damien Wassom William Asah Che Glen Takang Beyang Craftsman Ndula Ndula-Nan Landry Fotsing Silatsa Jospin Walter Kom Timma Marie-Paule Kengoum Djam Rosine Arckange Barakielle Bindzi Abah Nicolas Niemenak 《American Journal of Plant Sciences》 CAS 2024年第9期726-745,共20页
Plantain banana is an important cash crop that serves as stable food for millions of people around the world and contributes to income generation. Indeed, they provide a major staple food crop for millions of people a... Plantain banana is an important cash crop that serves as stable food for millions of people around the world and contributes to income generation. Indeed, they provide a major staple food crop for millions of people and play an important role in the social fabric of many rural communities. Plantain banana cultivation encounters major problem of seedlings unavailability that are essential for the creation of new plantations, as well as parasitic constraints. Mycosphaerella fijiensis is the main pathogen attack constraints of banana plant responsible of black Sigatoka disease, and viruses, which can severely reduce the photosynthetic leaf area, leading to banana production losses of more than 80% in plantations with soil fertility problems. The repeated use of synthetic input is the origin of contamination to the environment, different pollution sources of plants and human health, as well as resistance to some strains of pathogens and plant fertilization problems over time. Recent works carried out in nursery have shown that vivoplants of plantains treated with biostimulants based on natural products notably Tithonia diversifolia biopromote good growth and less susceptibility to M. fijiensis. Indeed, an increase in agromorphological characteristics, good accumulation of growth and defense biomarkers was also observed. In this context, Tithonia diversifolia is shown to be involved in the stimulatory effect mechanism of growth promotion and defensive reaction of plantain vivoplants against various pathogens and it is suggested to be acting as a vital stimulator. This article reviews the current state of knowledge on plantain banana cultivation constraints and on the potential of Tithonia diversifolia in relation with its different stimulatory effects on plantain vivoplants. 展开更多
关键词 Tithonia diversifolia Plantain Banana Black Sigatoka Disease Growth Biopromotion BIOPROTECTION induced Resistance Biofungicidal effect
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The neuroprotective effects of the anti-diabetic drug linagliptin against Aβ-induced neurotoxicity 被引量:2
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作者 Chih-Li Lin Chien-Ning Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期236-237,共2页
Impaired insulin signaling in Alzheimer’s disease(AD)brains:The insulin signaling pathway is a fundamental physiological mechanism that presents in nearly all vertebrate cells.However,sometimes cells stop respondi... Impaired insulin signaling in Alzheimer’s disease(AD)brains:The insulin signaling pathway is a fundamental physiological mechanism that presents in nearly all vertebrate cells.However,sometimes cells stop responding properly to insulin stimulation.This condition is known as insulin resistance,which is a hallmark of two very common conditions,metabolic syndrome and type 2 diabetes(T2D). 展开更多
关键词 GLP induced neurotoxicity DPP The neuroprotective effects of the anti-diabetic drug linagliptin against A AMPK
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Protective Effects of Dimethyl-4,4'-Dimethoxy-5,6,5',6'-Dimethylene Dioxybiphenyl-2,2'-Dicarboxylate on Damages of Isolated Rat Hepatocytes Induced by Carbon Tetrachloride and D-galactosamine 被引量:2
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作者 FU TIEBO AND LIU GENGTAODepartment of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences, 1 Xian Nong Tan Street, Beijing 100050,ChinaFox Chase Cancer Center. 7701 Burholme Avenue. Philadelphia, Pennsylvania 19111, USA.To whom correspondence should be addressed. 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第3期185-194,共10页
The protective effect of biphenyl dimethyl dicarboxylate (DDB) on chemically induced damages was studied in isolated suspended rat hepatocytes. The experimental results showed that DDB (200μg/106 cells) efficiently p... The protective effect of biphenyl dimethyl dicarboxylate (DDB) on chemically induced damages was studied in isolated suspended rat hepatocytes. The experimental results showed that DDB (200μg/106 cells) efficiently protected the hepatocytes against carbon tetrachloride (CC14 10 mrnol.L-1) and D-galactosamine (1 mmol.L-1) induced damages. Membranal lipid peroxidation (malondialdehyde, MDA formation) and glutamic pyruvic transaminase (GPT) release from the hepatocytes were markedly decreased. The damage of the cell surfaces of the hepatocytes were also reduced as seen under a scanning electron microscope (SEM). Pretreatment with DDB (300 mg-kg-1) orally ameliorated the reduction of liver glycogen and blood glucose caused by ip injection of D-galactosamine (800 mg-kg-1) in mice. When normal rats were given DDB 300 mg-kg-1 once daily for 10 d, the free ribosomal protein and RNA in the liver increased significantly. These results indicate that DDB is of beneficial effects on both damaged and normal hepatocytes. 展开更多
关键词 Protective effects of Dimethyl-4 4 Dimethylene Dioxybiphenyl-2 2 Dicarboxylate on Damages of Isolated Rat Hepatocytes induced by Carbon Tetrachloride and D-galactosamine Dimethoxy-5 6 5
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EFFECT OF HIGH-LIPID DIET ON GLOMERULAR MESANGIAL MATRIX IN ADRIAMYCIN-INDUCED NEPHROTIC RATS
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作者 宋红梅 李学旺 +1 位作者 魏珉 朱传酉 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第3期134-139,共6页
OBJECTIVE: To determine the effect of hypercholsterolemia induced by a high-lipid diet on glomerulosclerosis. METHODS: Twenty nephrotic syndrome (NS) Wistar rats administrated adriamycin (ADR) with a single intravenou... OBJECTIVE: To determine the effect of hypercholsterolemia induced by a high-lipid diet on glomerulosclerosis. METHODS: Twenty nephrotic syndrome (NS) Wistar rats administrated adriamycin (ADR) with a single intravenous dose of 5 mg/kg body weight, were divided into the standard and high-lipid chow groups. Another 20 weight-matched non-NS rats that received a vehicle alone were grouped as control. Urinary protein excretion and serum cholesterol were assayed; image analysis and techniques of pathology, immunohistochemistry, and molecular biology were used to determine morphological changes in glomeruli and the production of glomerular mesangial matrices in different groups. RESULTS: The serum total cholesterol level was significantly higher in rats with high-lipid chow in both non-NS [(2.2 +/- 0.3) g/L vs. (0.9 +/- 0.1) g/L, P 展开更多
关键词 adriamycin induced nephrosis high lipid diet glomerular mesangial matrixObjective. To determine the effect of hypercholesterolemia induced by a high-lipid diet on glomerulosclerosis. Methods. Twenty nephrotic syndrome (NS) Wistar rats admin
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Weight losing, antihyperlipidemic and cardioprotective effects of the alkaloid fraction of Hunteria umbellata seed extract on normal and triton-induced hyperlipidemic rats
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作者 Adejuwon Adewale Adeneye Peter Anthony Crooks 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第5期387-394,共8页
Objective: To investigate the weight losing, antihyperlipidemic and cardioprotective effects of the alkaloid fraction of Hunteria umbellata(H. umbellata) seed.Methods: Adult female Wistar rats(weight range: 120-150 g)... Objective: To investigate the weight losing, antihyperlipidemic and cardioprotective effects of the alkaloid fraction of Hunteria umbellata(H. umbellata) seed.Methods: Adult female Wistar rats(weight range: 120-150 g) were randomly divided into 4 and 5 treatment groups in the normal and triton-induced hyperlipidemic models, respectively. and were daily treated for 14 d before they were humanely sacrificed under inhaled diethyl ether anesthesia. About 5 mL of whole blood was obtained by cardiac puncture from each treated rat, from which serum for lipids assay was subsequently separated. Tissue samples of livers of treated rats were harvested and processed for histopathological analysis.Results: Repeated daily oral treatments of normal rats with 25 and 50 mg/kg/day of alkaloid fraction of H. umbellata resulted in significant(P<0.05 and P<0.001) and dose-dependent weight loss, and decreases in the serum triglyceride, total cholesterol and low density lipoprotein cholesterol, while significantly(P<0.001) increased the serum levels of high density lipoprotein cholesterol fraction. Similarly, oral pre-treatments with 25 and 50 mg/kg/day of alkaloid fraction of H. umbellata for 14 d before induction of hyperlipidemia with triton WR-1339 significantly(P<0.01, P<0.001) and dose-dependently attenuated increases in the average body weights, serum levels of triglyceride, total cholesterol and low density lipoprotein cholesterol while also significantly(P<0.01, P<0.001) and dose-dependently attenuated significant(P<0.001) decrease in the serum high-density lipoproteincholesterol levels when compared to the untreated control values. However, the results obtained for 50 mg/kg of alkaloid fraction of H. umbellata in both normal and triton WR-1339-induced hyperlipidemic rats were comparable to that recorded for 20 mg/kg of simvastatin. Similarly, oral pretreatments with 25 and 50 mg/kg/day of alkaloid fraction of H. umbellata significantly improved the histological lesions of fatty hepatic degeneration induced by triton WR-1339 treatment.Conclusions: Overall, results of this study showed that repeated oral treatments with 25 and 50 mg/kg/day of alkaloid fraction of H. umbellata elicited weight losing, antihyperlipidemic and cardioprotective effects in triton WR-1339 induced hyperlipidemic rats that were mediated via de novo cholesterol biosynthesis inhibition. 展开更多
关键词 Hunteria umbellata seeds ALKALOID fraction ANTIHYPERLipIDEMIC and CARDIOPROTECTIVE effects Triton WR 1339-induced HYPERLipIDEMIA RATS
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Analysis of <i>Momordica charantia</i>Polysaccharide Components and Their Effects on KA-Induced Oxidative Stress and Neuronal Loss in the Hippocampus of Epileptic Rats
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作者 Qiaoli Li Nan Chen +7 位作者 Heng Cai Yu Tang Xiaoyan Zhou Yue Huang Muxin Gong Cunyu Qin Xuewen Wei Suhua Qi 《World Journal of Neuroscience》 2018年第2期113-123,共11页
Polysaccharides of Momordica charantia have been reported to be the primary bioactive components that confer its antioxidant activity. To some degree, antioxidants may provide beneficial effects on neuronal damage ind... Polysaccharides of Momordica charantia have been reported to be the primary bioactive components that confer its antioxidant activity. To some degree, antioxidants may provide beneficial effects on neuronal damage induced by seizures. However, the protective effects of Momordica charantia polysaccharides (MCPs) on seizures remain unclear. In this study, our purpose was to investigate the effects of MCPs on oxidative stress and neurodegeneration in an experimental Kainic acid (KA)-induced rat seizure model. MCPs treatments decreased the level of malondialdehyde (MDA) and increased the activities of superoxide dismutase (SOD) and catalase (CAT) in the hippocampus of the KA-induced animal model. Moreover, MCPs significantly attenuated KA-induced neuronal loss in the CA1 and CA3 hippocampal regions. Based on these results, MCPs exert neuroprotective effects by attenuating KA-induced neuronal damage in the brain through their free radical scavenging activities. 展开更多
关键词 KA-induced SEIZURE Oxidative Stress Momordica charantia POLYSACCHARIDES Antioxidant NEUROPROTECTIVE effect
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1D Forward Simulation of MT Induced Polarization (IP) Effect of Reservoir
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作者 Yue An-ping Di Qing-yun Wang Miao-yue Shi Kun-fa 《石油地球物理勘探》 EI CSCD 北大核心 2009年第A02期142-150,共9页
关键词 激发极化 水库 正向模拟 频率电磁测深 频率范围 视电阻率 峰值频率 显示部分
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Induced Effects of Exogenous Phenolic Acids on Allelopathy of a Wild Rice Accession(Oryza longistaminata,S37) 被引量:4
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作者 Xu Gao-feng ZHANG Fu-dou LI Tian-lin Wu Di ZHANG Yu-hua 《Rice science》 SCIE 2010年第2期135-140,共6页
Four exogenous phenolic acids, including salicylic acid, fumalic acid, p-coumaric acid and p-hydroxybenzonic acid, were used to investigate the regulatory effects on allelopathy of a wild rice accession of S37 (Oryza... Four exogenous phenolic acids, including salicylic acid, fumalic acid, p-coumaric acid and p-hydroxybenzonic acid, were used to investigate the regulatory effects on allelopathy of a wild rice accession of S37 (Oryza Iongistaminata), which is a known allelopathic rice. The four exogenous phenolic acids induced the enhancement of the allelopathic potential of wild rice S37 in target weeds though the weed-suppressive activities were low, and the inducible effects were dependent on the specific phenolic acid, concentration and treatment time. After foliar application of exogenous phenolic acids, the inhibition rates for plant height, root length and fresh weight of barnyard grass (Echinochioa crus-galli) were significantly higher than those of the control. Especially at the concentration of 100 mg/L, the inhibition rates for plant height and fresh weight of barnyard grass by fumalic acid were 38.12% and 26.31% higher than those of the control, showing that fumalic acid was more effective compared with other phenolic acids in inhibiting monocotyledon weed growth. Furthermore, the weedsuppressive activity of aqueous extract from the leaves of wild rice S37 treated with exogenous phenolic acids was increased, and it peaked at 48 h after the treatment with the aqueous extract, and then gradually declined. 展开更多
关键词 salicylic acid fumalic acid p-coumaric acid p-hydroxybenzoic acid phenolic acid ALLELOPATHY inducible effect Oryza Iongistaminata
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Protective Effects of Shikonin on Brain Injury Induced by Carbon Ion Beam Irradiation in Mice 被引量:6
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作者 GAN Lu WANG Zhen Hua +6 位作者 ZHANG Hong ZHOU Rong SUN Chao LIU Yang SI Jing LIU Yuan Yuan WANG Zhen Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第2期148-151,共4页
Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed pr... Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group (P〈0.01), while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria. 展开更多
关键词 Protective effects of Shikonin on Brain Injury induced by Carbon Ion Beam Irradiation in Mice GSH SOD
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NONLINEAR EFFECT OF THE DUALFREQUENCY IP SPECTRUM 被引量:2
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作者 He Jishan Li Daqing Tang Jingtian(Department of Geology,Central South University of Technology,Changsha 410083) 《中国有色金属学会会刊:英文版》 EI CSCD 1995年第4期1-7,共7页
NONLINEAREFFECTOFTHEDUALFREQUENCYIPSPECTRUMHeJishan;LiDaqing;TangJingtian(DepartmentofGeology,CentralSouthUn... NONLINEAREFFECTOFTHEDUALFREQUENCYIPSPECTRUMHeJishan;LiDaqing;TangJingtian(DepartmentofGeology,CentralSouthUniversityofTechnol... 展开更多
关键词 nonlinear effect SPECTRAL CURVES SAWTOOTH FEATURE dualfrequency ip method
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Effects of Thermal Lattice Vibration on the Effective Potential of Weak-Coupling Bipolaron in a Quantum Dot 被引量:2
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作者 Eerdunchaolu Wuyunqimuge +2 位作者 XIAO Xin HAN Chao XIN Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期157-160,共4页
Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variationa... Based on the Huybrechts' linear-combination operator,effects of thermal lattice vibration on the effective potential of weak-coupling bipolaron in semiconductor quantum dots are studied by using the LLP variational method and quantum statistical theory.The results show that the absolute value of the induced potential of the bipolaron increases with increasing the electron-phonon coupling strength,but decreases with increasing the temperature and the distance of electrons,respectively;the absolute value of the effective potential increases with increasing the radius of the quantum dot,electron-phonon coupling strength and the distance of electrons,respectively,but decreases with increasing the temperature;the temperature and electron-phonon interaction have the important influence on the formation and state properties of the bipolaron:the bipolarons in the bound state are closer and more stable when the electron-phonon coupling strength is larger or the temperature is lower;the confinement potential and coulomb repulsive potential between electrons are unfavorable to the formation of bipolarons in the bound state. 展开更多
关键词 quantum dot BipOLARON induced potential effective potential thermal lattice vibration polaroneffects
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Dissipationless spin-Hall current contribution in the extrinsic spin-Hall effect 被引量:2
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作者 颜玉珍 李辉武 胡梁宾 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2981-2987,共7页
This paper shows that a substantial amount of dissipationless spin-Hall current contribution may exist in the extrinsic spin-Hall effect,which originates from the spin-orbit coupling induced by the applied external el... This paper shows that a substantial amount of dissipationless spin-Hall current contribution may exist in the extrinsic spin-Hall effect,which originates from the spin-orbit coupling induced by the applied external electric field itself that drives the extrinsic spin-Hall effect in a nonmagnetic semiconductor (or metal).By assuming that the impurity density is in a moderate range such that the total scattering potential due to all randomly distributed impurities is a smooth function of the space coordinate,it is shown that this dissipationless contribution shall be of the same orders of magnitude as the usual extrinsic contribution from spin-orbit dependent impurity scatterings (or may even be larger than the latter one).The theoretical results obtained are in good agreement with recent relevant experimental results. 展开更多
关键词 extrinsic spin-Hall effect spin-orbit coupling induced by external electric fields dissi-pationless spin current
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Effect of parameter setting and spectral normalization approach on study of matrix effect by laser induced breakdown spectroscopy of Ag–Zn binary composites 被引量:1
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作者 Harse SATTAR Liying SUN +3 位作者 Muhammad IMRAN Ran HAI Ding WU Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期155-166,共12页
The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical perfo... The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical performance of three different normalization methods, namely normalization with background, internal normalization and three point smoothing techniques at different parameter settings is studied for quantification of Ag and Zn by Laser induced breakdown spectroscopy(LIBS).The LIBS spectra of five known concentration of silver zinc binary composites have been investigated at various laser irradiances(LIs). Calibration curves for both Ag(I) line(4d^(10)5s^2S_(1/2)→4d^(10)5p^2P_(1/2) at 338.28 nm) and Zn(I) line(4s5s^3S_1→4s4p^3P_2 at 481.053 nm) have been determined at LI of 5.86?×?10^(10)W cm^(-2). Slopes of these calibration curves provide the valuation of matrix effect in the Ag–Zn composites. With careful sample preparation and normalization after smoothing at optimum parameter setting(OPS), the minimization of sample matrix effect has been successfully achieved. A good linearity has been obtained in Ag and Zn calibration curve at OPS when normalized the whole area of spectrum after smoothing and the obtained coefficients of determination values were R^2?=?0.995 and 0.998 closer to 1. The results of matrix effect have been further verified by analysis of plasma parameters. Both plasma parameters showed no change with varying concentration at OPS. However, at high concentration of Ag, the observed significant changes in both plasma parameters at common parameter setting PS-1 and PS-2 were the gesture of matrix effect. In our case, the better analytical results were obtained at smoothing function with optimized parameter setting that indicates it is more efficient than normalization with background and internal normalization method. 展开更多
关键词 Ag–Zn COMPOSITES laser induced BREAKDOWN spectroscopy optimum parameter setting SELF-ABSORPTION matrix effect
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Effect of Cycloheximide on the Adaptive Response Induced by Low Dose Radiation 被引量:4
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作者 CAI Lu AND LIu SHUZHENGDepartment of Radiation Biology, Institute of Radiation Medicine, Norman Bethune University of Medical Sciences, Changchun 130021, China Corresponding author 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第1期46-52,共7页
Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhi... Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis. 展开更多
关键词 In effect of Cycloheximide on the Adaptive Response induced by Low Dose Radiation
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Experimental Study of Induced Polarization Effect in Unconventional Reservoir Rocks 被引量:4
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作者 Vladimir Burtman Haiyan Fu Michael S. Zhdanov 《Geomaterials》 2014年第4期117-128,共12页
Unconventional hydrocarbon reserves substantially surpass those of conventional resources and therefore are extremely economically attractive. However, exploration and production of uncon-ventional reserves is challen... Unconventional hydrocarbon reserves substantially surpass those of conventional resources and therefore are extremely economically attractive. However, exploration and production of uncon-ventional reserves is challenging. This paper demonstrates that one can observe significant induced polarization effects in shale reservoir rocks, which can be used in exploration for unconventional reserves. The generalized effective-medium theory of induced polarization (GEMTIP) was used to model the complex resistivity of shale rocks. We demonstrate that GEMTIP modeling provides an evaluation of mineral composition and volume fractions in rock samples. We have conducted spectral induced polarization (IP) measurements using different types of shale rocks to test the feasibility of the IP method and GEMTIP modeling for studying unconventional hydrocarbon (HC) reservoir rocks. 展开更多
关键词 UNCONVENTIONAL Energy RESOURCES EM EXPLORATION induced POLARIZATION effective MEDIUM
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A Review on Chemical Effects in Aqueous Solution induced by Plasma with Glow Discharge 被引量:5
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作者 高锦章 王晓艳 +2 位作者 胡中爱 侯经国 陆泉芳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第3期765-774,共10页
Chemical effects in different aqueous solutions induced by plasma with glow discharge electrolysis (GDE) and contact glow discharge electrolysis (CGDE) are described in this paper. The experimental and discharge char... Chemical effects in different aqueous solutions induced by plasma with glow discharge electrolysis (GDE) and contact glow discharge electrolysis (CGDE) are described in this paper. The experimental and discharge characteristics are also reviewed. These are followed by a discussion of their mechanisms of both anodic and cathodic CGDE.. 展开更多
关键词 A Review on Chemical effects in Aqueous Solution induced by Plasma with Glow Discharge GDE
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The Effect of Chinese Tea on Occurrence of Esophageal Tumor Induced by N-Nitrosomethylbenzylamine in Rats 被引量:11
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作者 HI AND XU YONG Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine, Beijing, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第1期35-42,共8页
Five groups of rats (40 rats per group) were given five different varieties of Chinese tea (1 g/50 ml) and another two groups of rats (a positive control and a negative control) were given tap water as drinking water.... Five groups of rats (40 rats per group) were given five different varieties of Chinese tea (1 g/50 ml) and another two groups of rats (a positive control and a negative control) were given tap water as drinking water. Except for the negative control group, all the animals were intubated with A'-nitrosomethyibenzylamine (NMBzA, 5 mg/kg body wt/week). Half of the animals in each group were sacrificed after 6 weeks and the remaining animals at the end of 12 weeks. The incidences of esophageal mucosa lesions (16-59%) at the end of6 weeks were significantly lower in the tea-treated rats than in the positive control group (100%). The incidences of esophageal tumor at the end of 12 weeks (42-67%) were also significantly lower in the tea-treated groups than in the positive control group (90%). The same phenomenon was found with respect to the size and number of tumors in each tumor-bearing animal. The relative anticarcinogenic effects of the five varieties of Chinese tea were different. The Fujian oolong tea and jasmine tea exhibited the strongest effects. The results suggest that Chinese tea can effectively inhibit the carcinogenesis Caused by an N-nitroso compound. 1990 Academic Press.Inc. 展开更多
关键词 The effect of Chinese Tea on Occurrence of Esophageal Tumor induced by N-Nitrosomethylbenzylamine in Rats
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Effect of 1, 25-Dihydroxyvitamin D_3 on Gastric Carcinogenesis Induced by N-Methyl-N'-nitro-N-nitrosoguanidine in Rats 被引量:2
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作者 GAO GUO-LIN YANG YUAN +2 位作者 YANG SI-FENG WANG FU-MEI YOU LI-RONG AND ZHANG FENG-YUN(Gastroenterological Center, Hospital No. 222, PLA,Jilin 132011, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第2期147-155,共9页
The effect of 1, 25-dihydroxyvitamin D3 (1, 25 (OH)2D3) given in the post-initiation stage of gastric carcinogenesis induced by N-methyl-N-nitro-N-nitrosoguanidine (MNNG) was investigated in male Wistar rats. Gastric ... The effect of 1, 25-dihydroxyvitamin D3 (1, 25 (OH)2D3) given in the post-initiation stage of gastric carcinogenesis induced by N-methyl-N-nitro-N-nitrosoguanidine (MNNG) was investigated in male Wistar rats. Gastric carcinogenesis in rats was induced by administration of MNNG (150 mg·L-1) in drinking water. Four weeks after MNNG exposure, the rats were switched to the diet containing 1, 25 (OH)2D3 (2. 5 μg·kg-1 and 5. 0 μg·kg-1) and maintained on the diet. Animals were killed at week 16 and week 32 for immunohistochemical and histopathological studies. At week 16, the proliferating cell nuclear antingen (PCNA) labeling index in epithelium from the glandular stomach of rats that received 1, 25 (OH)2D3 (5.0 μg·kg-1) in combination with MNNG (150 mg·L-1) were significantly higher when compared with the rats receiving MNNG alone. Supplementation of 1, 25 (OH)2D3 (5. 0 μg·kg-1) in the rats' diet caused a dramatic increase in carcinoma incidence, and the number of individual cancer foci in the glandular stomach of rats receiving MNNG at week 32. It was concluded that certain dose of 1, 25 (OH)2D3 enhanced gastric carcinogenesis induced by MNNG in rats. 展开更多
关键词 Dihydroxyvitamin D3 on Gastric Carcinogenesis induced by N-Methyl-N effect of 1 nitro-N-nitrosoguanidine in Rats
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A Thermal Analogue of the Zel’Dovich Effect
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作者 Gianpaolo Bei 《Journal of Applied Mathematics and Physics》 2023年第12期3970-3983,共14页
We analyze in this work anisotropic heat conduction induced by a harmonically oscillating laser source incident on rotating conductors, exploiting an analogy with an effect discovered long ago, called the Zel’dovich ... We analyze in this work anisotropic heat conduction induced by a harmonically oscillating laser source incident on rotating conductors, exploiting an analogy with an effect discovered long ago, called the Zel’dovich effect. We re-covered the main results of a recently published paper that predicts the translational Doppler frequency shift of a thermal wave induced on a sample moving with uniform rectilinear motion. We extend then this framework to take into account the frequency shift of a thermal field propagating on a rotating platform. We show that it coincides with the rotational frequency shift which has been recently observed on surface acoustic waves and hydrodynamic surface waves, called rotational superradiance. Finally, we use an analogy with the Tolman effect to deduce a simple estimate of the average temperature gradient induced by rotation, showing the existence of a new cooling effect associated with heat torque transfer. 展开更多
关键词 Anisotropic Heat Diffusion Chiral Spinning Thermal Waves Heat Vortex Beams Thermal Doppler effect Thermal Zel’dovich effect Thermal Polarization Vector Rotation induced Tolman Cooling effect
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Characteristics of anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic,extrinsic,and external electric-field induced spin-orbit couplings 被引量:1
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作者 Liu Song Yan Yu-Zhen Hu Liang-Bin 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期469-476,共8页
The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling we... The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling were investigated theoretically. Based on a unified semiclassical theoretical approach, it is shown that the total anomalous Hall conductivity can be expressed as the sum of three distinct contributions in the presence of these competing spin-orbit interactions, namely an intrinsic contribution determined by the Berry curvature in the momentum space, an extrinsic contribution determined by the modified Bloch band group velocity and an extrinsic contribution determined by spin-orbit-dependent impurity scattering. The characteristics of these competing contributions are discussed in detail in the paper. 展开更多
关键词 anomalous Hall effect intrinsic spin orbit coupling extrinsic spin orbit coupling exter- nal electric-field induced spin-orbit coupling
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