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Gate-field control of valley polarization in valleytronics
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作者 张婷婷 韩依琳 +1 位作者 张闰午 余智明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期2-12,共11页
Valleytronics materials are a kind of special semiconductors which can host multiple symmetry-connected and wellseparated electron or hole pockets in the Brillouin zone when the system is slightly n or p doped. Since ... Valleytronics materials are a kind of special semiconductors which can host multiple symmetry-connected and wellseparated electron or hole pockets in the Brillouin zone when the system is slightly n or p doped. Since the low-energy particles residing in these pockets generally are not easily scattered to each other by small perturbations, they are endowed with an additional valley degree of freedom. Analogous to spin, the valley freedom can be used to process information,leading to the concept of valleytronics. The prerequisite for valleytronics is the generation of valley polarization. Thus,a focus in this field is achieving the electric generation of valley polarization, especially the static generation by the gate electric field alone. In this work, we briefly review the latest progress in this research direction, focusing on the concepts of the couplings between valley and layer, i.e., the valley–layer coupling which permits the gate-field control of the valley polarization, the couplings between valley, layer, and spin in magnetic systems, the physical properties, the novel designing schemes for electronic devices, and the material realizations of the gate-controlled valleytronics materials. 展开更多
关键词 band structure electronic transport optical properties SPINTRONICS
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Pre-existing orthorhombic embryos-induced hexagonal-orthorhombic martensitic transformation in MnNiSi_(1-x)(CoNiGe)_x alloy
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作者 张婷婷 龚元元 +1 位作者 鲁子骞 徐锋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期691-699,共9页
The thermal-elastic martensitic transformation from high-temperature Ni_(2)In-type hexagonal structure to low-temperature TiNiSi-type orthorhombic structure has been widely studied in MnMX(M=Ni or Co,and X=Ge or Si)al... The thermal-elastic martensitic transformation from high-temperature Ni_(2)In-type hexagonal structure to low-temperature TiNiSi-type orthorhombic structure has been widely studied in MnMX(M=Ni or Co,and X=Ge or Si)alloys.However,the answer to how the orthorhombic martensite nucleates and grows within the hexagonal parent is still unclear.In this work,the hexagonal-orthorhombic martensitic transformation in a Co and Ge co-substituted MnNiSi is investigated.One can find some orthorhombic laths embedded in the hexagonal parent at a temperature above the martensitic transformation start temperature(M_(s)).With the the sample cooing to M_(s),the laths turn broader,indicating that the martensitic transformation starts from these pre-existing orthorhombic laths.Microstructure observation suggests that these pre-existing orthorhombic laths do not originate from the hexagonal-orthorhombic martensitic transformation because of the difference between atomic occupations of doping elements in the hexagonal parent and those in the preexisting orthorhombic laths.The phenomenological crystallographic theory and experimental investigations prove that the pre-existing orthorhombic lath and generated orthorhombic martensite have the same crystallography relationship to the hexagonal parent.Therefore,the orthorhombic martensite can take these pre-existing laths as embryos and grow up.This work implies that the martensitic transformation in MnNiSi_(1-x)(CoNiGe)_(x) alloy is initiated by orthorhombic embryos. 展开更多
关键词 martensitic transformation MnMX alloy orthorhombic embryo crystallography relationship
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Synergistic effects of three traditional herbs green tea,mulberry leaf and corn silk on glucose uptake level of L6 myoblasts and the hypoglycemic mechanism
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作者 Jing-Na Zhou Ming-Yue Li +4 位作者 ting-ting zhang Jing-Yang Lu Min zhang Peng-Wei Zhuang Hai-Xia Chen 《Traditional Medicine Research》 2024年第7期1-12,共12页
Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear... Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear.Methods:The effective components of green tea,mulberry leaf and corn silk were extracted and enriched.Mixture design of experiments was used to study the influences of different combinations on the cell viability and glucose uptake level of L6 myoblasts,so as to determine the optimal synergistic hypoglycemic combination.The possible hypoglycemic mechanism of the optimal synergistic combination was explored by cytotoxicity assay,glucose uptake assay,and western blot.Results:Three polyphenol enrichment fractions of the herbs,30%ethanol elution fraction of green tea(GT),50%ethanol elution fraction of mulberry leaf(ML)and 60%ethanol elution fraction of corn silk(CS)were obtained.The antioxidant activities of GT-30%,ML-50%and CS-60%were superior to those of crude extracts,and showed strong potential inα-amylase andα-glucosidase inhibition activities.The optimal synergistic combination of crude extracts G7(crude extract of green tea:crude extract of mulberry leaf:crude extract of corn silk=1:5:3),polyphenol enrichment fractions R3(GT-30%:ML-50%:CS-60%=1:7:1)and monomers X2(epigallocatechin gallate:morusin:formononetin=3:1:2)were selected,respectively.G7,R3,and X2 showed promoting effects on the cell viability and glucose uptake of L6 myoblasts within the detected concentration range.In addition,G7,R3,and X2 could increase the expression levels of p-PI3K/PI3K and p-Akt/Akt in L6 myoblasts,and promote the translocation of Glut4,but G7 and R3 showed more significant effects.Conclusion:The synergistic hypoglycemic effects of green tea,mulberry leaf and corn silk had the characteristics of multiple-components and multiple-targets with p-PI3K/PI3K,p-Akt/Akt and the translocation of Glut4 signal pathways involved.The three traditional herbs might have the potential to be combined used for the prevention and treatment of diabetes based on the synergistic hypoglycemic effects. 展开更多
关键词 green tea mulberry leaf corn silk synergistic effect type 2 diabetes mellitus mechanism
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23G玻璃体切除术及硅油辅助取出眼内巨大异物的临床观察 被引量:14
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作者 陈忠平 覃星妹 +1 位作者 张婷婷 陈娟 《国际眼科杂志》 CAS 北大核心 2018年第1期172-174,共3页
目的:研究23G微创玻璃体切除术及硅油辅助下取出眼内巨大异物的手术效果及并发症。方法:回顾性分析2012-02/2015-03在长沙爱尔眼科医院接受治疗、需填充硅油的眼内巨大异物的患者12例12眼,其中男11例11眼,女1例1眼。术前视力光感~0.1,1... 目的:研究23G微创玻璃体切除术及硅油辅助下取出眼内巨大异物的手术效果及并发症。方法:回顾性分析2012-02/2015-03在长沙爱尔眼科医院接受治疗、需填充硅油的眼内巨大异物的患者12例12眼,其中男11例11眼,女1例1眼。术前视力光感~0.1,12眼术前均合并视网膜脱离。所有患者均接受23G微创玻璃体切除手术,在切除玻璃体和修复损伤的视网膜后,先行硅油填充,再扩大巩膜切口取出眼内巨大异物。术后6mo取硅油,部分患者联合人工晶状体植入。结果:患者12眼眼内巨大异物均一次性取出,未出现再次跌落损伤视网膜现象,切口无视网膜脱出,不损伤角膜。术后视网膜均复位,未出现术后眼内炎。术后6mo硅油均顺利取出,视力均提高,脱盲率达67%,脱残率达到25%。结论:23G微创玻璃体切除术及硅油辅助下取出眼内巨大异物是一种安全有效的方法。 展开更多
关键词 眼内异物 玻璃体切除术 硅油 眼损伤
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Pathological process of liver sinusoidal endothelial cells in liver diseases 被引量:13
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作者 yao ni juan-mei li +5 位作者 ming-kun liu ting-ting zhang dong-ping wang wen-hui zhou ling-zi hu wen-liang lv 《World Journal of Gastroenterology》 SCIE CAS 2017年第43期7666-7677,共12页
Cirrhosis develops from liver fibrosis and is the severe pathological stage of all chronic liver injury. Cirrhosis caused by hepatitis B virus and hepatitis C virus infection is especially common. Liver fibrosis and c... Cirrhosis develops from liver fibrosis and is the severe pathological stage of all chronic liver injury. Cirrhosis caused by hepatitis B virus and hepatitis C virus infection is especially common. Liver fibrosis and cirrhosis involve excess production of extracellular matrix,which is closely related to liver sinusoidal endothelial cells(LSECs). Damaged LSECs can synthesize transforming growth factor-beta and platelet-derived growth factor,which activate hepatic stellate cells and facilitate the synthesis of extracellular matrix. Herein,we highlight the angiogenic cytokines of LSECs related to liver fibrosis and cirrhosis at different stages and focus on the formation and development of liver fibrosis and cirrhosis. Inhibition of LSEC angiogenesis and antiangiogenic therapy are described in detail. Targeting LSECs has high therapeutic potential for liver diseases. Further understanding of the mechanism of action will provide stronger evidence for the development of anti-LSEC drugs and new directions for diagnosis and treatment of liver diseases. 展开更多
关键词 正弦曲线 endothelial 房间 肝炎 纤维变性 肝硬化 肝疾病
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Genetic structure,gene flow pattern,and association analysis of superior germplasm resources in domesticated upland cotton(Gossypium hirsutum L.) 被引量:3
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作者 ting-ting zhang Na-Yao zhang +11 位作者 Wei Li Xiao-Jian Zhou Xiao-Yu Pei Yan-Gai Liu Zhong-Ying Ren Kun-Lun He Wen-Sheng zhang Ke-Hai Zhou Fei zhang Xiong-Feng Ma Dai-Gang Yang Zhong-Hu Li 《Plant Diversity》 SCIE CAS CSCD 2020年第3期189-197,共9页
Gene flow patterns and the genetic structure of domesticated crops like cotton are not well understood.Furthermore,marker-assisted breeding of cotton has lagged far behind that of other major crops because the loci as... Gene flow patterns and the genetic structure of domesticated crops like cotton are not well understood.Furthermore,marker-assisted breeding of cotton has lagged far behind that of other major crops because the loci associated with cotton traits such as fiber yield and quality have scarcely been identified.In this study,we used 19 microsatellites to first determine the population genetic structure and patterns of gene flow of superior germplasm resources in upland cotton.We then used association analysis to identify which markers were associated with 15 agronomic traits(including ten yield and five fiber quality traits).The results showed that the upland cotton accessions have low levels of genetic diversity(polymorphism information content=0.427),although extensive gene flow occurred among different ecological and geographic regions.Bayesian clustering analysis indicated that the cotton resources used in this study did not belong to obvious geographic populations,which may be the consequence of a single source of domestication followed by frequent genetic introgression mediated by human transference.A total of 82 maker-trait associations were examined in association analysis and the related ratios for phenotypic variations ranged from 3.04% to 47.14%.Interestingly,nine SSR markers were detected in more than one environmental condition.In addition,14 SSR markers were co-associated with two or more different traits.It was noteworthy that NAU4860 and NAU5077 markers detected at least in two environments were simultaneously associated with three fiber quality traits(uniformity index,specific breaking strength and micronaire value).In conclusion,these findings provide new insights into the population structure and genetic exchange pattern of cultivated cotton accessions.The quantitative trait loci of domesticated cotton identified will also be very useful for improvement of yield and fiber quality of cotton in molecular breeding programs. 展开更多
关键词 Domestication cotton Fiber quality traits Genetic exchange Microsatellite markers Yield
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The relationship between serum miR-21 levels and left atrium dilation in elderly patients with essential hypertension 被引量:1
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作者 Yan WANG Guang-Ping FU +5 位作者 Qiu-Yan WANG ting-ting zhang Li-Li HE Qing-Juan ZUO Chang-Lei zhang Yi-Fang GUO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2022年第11期833-842,共10页
BACKGROUND MicroRNA-21(miR-21)is related to hypertension and cardiac remodelling.Left atrium(LA)dilation is highly sensitive to small haemodynamic changes in the left ventricle(LV)that are induced by hypertension.This... BACKGROUND MicroRNA-21(miR-21)is related to hypertension and cardiac remodelling.Left atrium(LA)dilation is highly sensitive to small haemodynamic changes in the left ventricle(LV)that are induced by hypertension.This study aimed to elucidate the relationship between miR-21 expression and LA dilation in elderly patients with essential hypertension(EH).METHODS In this cross-sectional study,one hundred elderly patients with EH were recruited for the study.According to their left atrium diameters(LADs),the patients were divided into the LA dilation group[42 patients(42%)]and the no-LA dilation group[58 patients(58%)].The serum levels of miR-21 and chemical biomarkers used in the clinic,such as creatinine,blood urea nitrogen,uric acid,fasting blood glucose,total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDLC),low-density lipoprotein cholesterol(LDL-C),very-low-density lipoprotein cholesterol,Lp(a),apolipoprotein A1(apoA1),and apolipoprotein B,were measured.All the patients underwent echocardiographic examination,and the LAD,interventricular septum(IVS),right atrium diameter(RAD),right ventricle diameter(RVD),left ventricular end-systolic diameter(LVESD),left ventricular end-systolic diameter(LVEDD)and left ventricular ejection fraction(LVEF)were measured.RESULTS The levels of miR-21[8.02(5.21,14.39)vs.6.05(3.81,8.95),P=0.011]and LVEF(67.02±3.82 vs.64.14±4.43,P=0.001)were higher in the LA dilation group.The levels of creatinine[70.40(64.45,80.15)vs.63.9(60.1,73.43)],P=0.020]were higher in the no-LA dilation group.The levels of HDLC(r=-0.209,P=0.037),apoA1(r=-0.269,P=0.007)and RAD(r=0.203,P=0.043)were significantly correlated with miR-21 expression.The LAD was significantly correlated with the RAD(r=0.287,P=0.004),RVD(r=0.450,P<0.001),LVEDD(r=0.248,P=0.013)and LVEF(r=0.232,P=0.020).Multivariate logistic regression revealed that miR-21 significantly influenced LA dilation in elderly patients with EH(P<0.05).CONCLUSIONS Circulating serum levels of miR-21 are increased in elderly patients with EH with LA dilation.miR-21 levels are significantly correlated with LA dilation in elderly patients with EH,and miR-21 may be a factor related to the clinical pathophysiological occurrence of and treatment for the progression of hypertension-related early heart damage in EH patients. 展开更多
关键词 patients HYPERTENSION ATRIUM
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Effect of Chemical Doping on the Electronic Transport Properties of Tailoring Graphene Nanoribbons 被引量:1
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作者 刘洋 夏蔡娟 +3 位作者 张博群 张婷婷 崔焱 胡振洋 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第6期62-65,共4页
The electronic transport properties of a molecular junction based on doping tailoring armchair-type graphene nanoribbons(AGNRs)with different widths are investigated by applying the non-equilibrium Green's function... The electronic transport properties of a molecular junction based on doping tailoring armchair-type graphene nanoribbons(AGNRs)with different widths are investigated by applying the non-equilibrium Green's function formalism combined with first-principles density functional theory.The calculated results show that the width and doping play significant roles in the electronic transport properties of the molecular junction.A higher current can be obtained for the molecular junctions with the tailoring AGNRs with W=11.Furthermore,the current of boron-doped tailoring AGNRs with widths W=7 is nearly four times larger than that of the undoped one,which can be potentially useful for the design of high performance electronic devices. 展开更多
关键词 Effect of Chemical Doping on the Electronic Transport Properties of Tailoring Graphene Nanoribbons
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Nonlocal effect on resonant radiation force exerted on semiconductor coupled quantum well nanostructures
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作者 张金珂 张婷婷 +2 位作者 张玉亮 王光辉 邓冬梅 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期349-356,共8页
Based on the microscopic nonlocal optical response theory, the resonant radiation force exerted on a semiconductorcoupled quantum well nanostructure(CQWN), induced by the nonlocal interaction between lasers and electr... Based on the microscopic nonlocal optical response theory, the resonant radiation force exerted on a semiconductorcoupled quantum well nanostructure(CQWN), induced by the nonlocal interaction between lasers and electrons in conduction bands, is investigated for two different polarized states. The numerical results show that the spatial nonlocality of optical response can cause a radiation shift(blue-shift) for the spectrum of the resonant radiation force, which is dependent on the CQWN width ratio, the barrier height, and polarized states sensitively. It is also confirmed that the resonant radiation force is steerable by the incident and polarized directions of incident light. This work may provide an advantageous method for detecting internal quantum properties of nanostructures, and open novel and raising possibilities for optical manipulation of nano-objects using laser-induced radiation force. 展开更多
关键词 NONLOCAL effect RESONANT radiation FORCE coupled quantum WELL
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Preparation of PSFO and LPSFO nanofibers by electrospinning and their electronic transport and magnetic properties
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作者 苏影 朱东阳 +5 位作者 张亭亭 张玉瑞 韩文鹏 张俊 Seeram Ramakrishna 龙云泽 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期629-635,共7页
Pr_(0.5)Sr_(0.5)FeO_(3)(PSFO)and La_(0.25)Pr_(0.25)Sr_(0.5)FeO_(3)(LPSFO)nanofibers are prepared by electrospinning followed by calcination,and their morphologies,microstructures,electronic transports,and magnetic pro... Pr_(0.5)Sr_(0.5)FeO_(3)(PSFO)and La_(0.25)Pr_(0.25)Sr_(0.5)FeO_(3)(LPSFO)nanofibers are prepared by electrospinning followed by calcination,and their morphologies,microstructures,electronic transports,and magnetic properties are studied systematically.The temperature-dependent resistance curves of PSFO and LPSFO nanofibers are measured in a temperature range from 300 K to 10 K.With the temperature lowering,the resistance increases gradually and then decreases sharply due to the occurrence of ferromagnetic metal phase.The metal-insulator transition temperatures are about 110 K and 180 K for PSFO and LPSFO nanofibers,respectively.The electronic conduction behavior above the transition temperature can be described by one-dimensional Mott’s variable-range hopping(VRH)model.The hysteresis loops and the field-cooled(FC)and zero-field-cooled(ZFC)curves show that both PSFO nanofiber and LPSFO nanofiber exhibit ferromagnetism.Although the doping of La reduces the overall magnetization intensity of the material,it increases the ferromagnetic ratio of the system,which may improve the performance of LPSFO in solid oxide fuel cell. 展开更多
关键词 Pr_(0.5)Sr_(0.5)FeO_(3) La_(0.25)Pr_(0.25)Sr_(0.5)FeO_(3) ELECTROSPINNING electronic transport magnetic properties
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Epitaxial growth and transport properties of compressively-strained Ba_(2)IrO_(4) films
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作者 赵蕴琦 张衡 +7 位作者 蔡祥滨 郭维 季殿祥 张婷婷 顾正彬 周健 朱叶 聂越峰 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期492-495,共4页
Ba_(2)IrO_(4) is a sister compound of the widely investigated Sr_(2)IrO_(4) and has no IrO_(6) octahedral rotation nor net canted antiferromagnetic moment,thus it acts as a system more similar to the high-T_(c) cuprat... Ba_(2)IrO_(4) is a sister compound of the widely investigated Sr_(2)IrO_(4) and has no IrO_(6) octahedral rotation nor net canted antiferromagnetic moment,thus it acts as a system more similar to the high-T_(c) cuprate.In this work,we synthesize the Ba_(2)IrO_(4) epitaxial films by reactive molecular beam epitaxy and study their crystalline structure and transport properties under biaxial compressive strain.High resolution scanning transmission electron microscopy and x-ray diffraction confirm the high quality of films with partial strain relaxation.Under compressive epitaxial strain,the Ba_(2)IrO_(4) exhibits the strain-driven enhancement of the conductivity,consistent with the band gap narrowing and the stronger hybridization of Ir-t_(2g) and O-2p orbitals predicted in the first-principles calculations. 展开更多
关键词 molecular beam epitaxy iridate oxides epitaxial strain transport properties
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Effects of “Caulis Sargentodoxae Formula” on Experimental Endometriosis in Rat
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作者 ting-ting zhang Qi CHEN +5 位作者 Kang-mei ZHU Lin CAO Gui-lin HE Gui-ming LIU Lan-di SHU De-ying DAI 《Journal of Reproduction and Contraception》 CAS 2005年第4期213-218,共6页
Objective To study the drug effects of "Caulis Sargentodoxae Formula" which dears away heat and blood clot on experimental endometriosis in rat, and to compare this effect with Danazol's effects. Method The model o... Objective To study the drug effects of "Caulis Sargentodoxae Formula" which dears away heat and blood clot on experimental endometriosis in rat, and to compare this effect with Danazol's effects. Method The model of endometriosis rat was induced by transplanting with endometrium surgically The rats were divided into 6 groups randomly: the non-treatment group, the castrate group, Danazol group(80 mg/kg), "Caulis Sargentodoxae Formula" group (110 g/kg), the medium dose group(77.5 g/kg) and the low dose group(55 g/kg). After 3 weeks' treatment, the volume ofendometrium was detected by cutting the rats' belly open, drawing the materials from endometrium for tissue section, and doing the quantity analysis of endometrium by semiautomatic image analysis machine.Results There was no significant difference of the endometrium volumes between the low dose group and the non-treatment group(P〉O.05), other groups' endometrium volumes were significantly lower than those of the non-treatment group(P〈0. 05). And apart from the low dose group, all other groups' heights of the endometrium epithelia were significantly lower than that of the non-treatment group(p〈0.01). Conclusion "Caulis Sargentodoxae Formula" can refrain the growth of the endometrium, and the effects are better than that of Danazol's. 展开更多
关键词 "Caulis Sargentodoxae Formula" ENDOMETRIOSIS RAT drug effects
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An Anterior Cingulate Cortex-to-Midbrain Projection Controls Chronic Itch in
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作者 ting-ting zhang Su-Shan Guo +7 位作者 Hui-Ying Wang Qi Jing Xin Yi Zi-Han Hu Xin-Ren Yu Tian-Le Xu Ming-Gang Liu Xuan Zhao 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第5期793-807,共15页
Itch is an unpleasant sensation that provokes the desire to scratch.While acute itch serves as a protec-tive system to warn the body of external irritating agents,chronic itch is a debilitating but poorly-treated clin... Itch is an unpleasant sensation that provokes the desire to scratch.While acute itch serves as a protec-tive system to warn the body of external irritating agents,chronic itch is a debilitating but poorly-treated clinical dis-ease leading to repetitive scratching and skin lesions.How-ever,the neural mechanisms underlying the pathophysiol-ogy of chronic itch remain mysterious.Here,we identified a cell type-dependent role of the anterior cingulate cortex(ACC)in controlling chronic itch-related excessive scratch-ing behaviors in mice.Moreover,we delineated a neural circuit originating from excitatory neurons of the ACC to the ventral tegmental area(VTA)that was critically involved in chronic itch.Furthermore,we demonstrate that the ACC→VTA circuit also selectively modulated histaminergic acute itch.Finally,the ACC neurons were shown to predomi-nantly innervate the non-dopaminergic neurons of the VTA.Taken together,our findings uncover a cortex-midbrain cir-cuit for chronic itch-evoked scratching behaviors and shed novel insights on therapeutic intervention. 展开更多
关键词 sAnterior cingulate cortex Chronic itch Ventral tegmental area-Chemogenetics Neural circuit
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A Cross-linked Polyethylene with Recyclability and Mechanical Robustness Enabled by Establishment of Multiple Hydrogen Bonds Network via Reactive Melt Blending
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作者 Hong-Da Mao ting-ting zhang +4 位作者 Zhen-You Guo Dong-Yu Bai Jie Wang Hao Xiu Qiang Fu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第7期1104-1114,共11页
Physical cross-linking by hydrogen-bonds (H-bonds), providing a good combination of application properties of thermosets and processability of thermoplastics, is a potential strategy to resolve the recycling problem o... Physical cross-linking by hydrogen-bonds (H-bonds), providing a good combination of application properties of thermosets and processability of thermoplastics, is a potential strategy to resolve the recycling problem of traditional chemically cross-linked polyethylene. However, ureidopyrimidone (UPy), the most widely used H-bonding motif, is unfavorable for large-scale industrial application due to its poor thermal stability. In this work, H-bonds cross-linked polyethylene was successfully prepared by reactive melt blending maleic anhydride grafted polyethylene (PE-g-MAH) with 3-amino-1,2,4-triazole (ATA) to form amide triazole ring-carboxylic acid units. Triazole ring can easily generate multiple H-bonds with carboxylic acid and amide. More importantly, these units are more thermal stable than UPy due to the absence of unstable urea group of UPy. The introduction of H-bonds cross-linking leads to an obvious improvement in mechanical properties and creep resistance and a good maintain in thermal properties and recyclability. Furthermore, the reinforcement effect monotonically improves with increasing the density of H-bonds. The obtained good properties are mainly attributed to largely enhanced interchain interactions induced by H-bonds cross-linking and intrinsic reversibility of H-bonds. This work develops a novel way for the simple fabrication of H-bonds cross-linked PE with high performance through reactive melt blending. 展开更多
关键词 Cross-linked polyethylene Hydrogen bonds RECYCLABILITY
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Pompon-like NiCo_(2)O_(4) nanospheres:a potential candidate for the counter electrode in quantum dot-sensitized solar cells
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作者 Qiu zhang ting-ting zhang +1 位作者 Feng-Yan Li Lin Xu 《Tungsten》 EI CSCD 2023年第2期235-246,共12页
To find a novel counter electrode(CE)material for quantum dot-sensitized solar cells(QDSSCs),pompon-like NiCo_(2)O_(4) nanospheres are synthesized by a facile solvothermal and post-calcination method and we attempt to... To find a novel counter electrode(CE)material for quantum dot-sensitized solar cells(QDSSCs),pompon-like NiCo_(2)O_(4) nanospheres are synthesized by a facile solvothermal and post-calcination method and we attempt to apply it as a CE material for QDS SC.The catalytic performance of NiCo_(2)O_(4) counter electrode is investigated in detail through electrochemical impedance spectroscopy,Tafel test and cyclic voltammetry.The catalytic activity of NiCo_(2)O_(4) CE is superior to that of nanoflower-like Cu2S CE and traditional Cu2S/brass CE,which is mainly attributed to the large specific surface area,outstanding electrical conductivity of bimetallic oxides and the synergistic promotion effect of metals with different valence states.Under standard sunlight(air mass AM 1.5G 100 mW·cm^(-2)),the CdS/CdSe/ZnS-sensitized solar cell assembled with NiCo_(2)O_(4) CE achieved a photoelectric conversion efficiency of 5.55%,with a short current density of 22.49 mA·cm^(-2),an open circuit voltage of 0.574 V,and a fill factor of 0.43,which is slightly higher than the QDSSCs with nanoflower-like Cu_(2)S CE(4.75%)and traditional Cu_(2)S/brass CE(4.69%).This research provides ideas for discovering innovative and efficient CE materials for QDSSCs. 展开更多
关键词 QDSSCs Counter electrodes NiCo_(2)O_(4) Cu_(2)S
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针刺得气对功能性消化不良患者前扣带回-默认网络功能连接度的影响 被引量:7
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作者 孙睿睿 马培宏 +12 位作者 何昭璇 尹涛 瞿玉竹 印帅 刘小艳 卢晋 张婷婷 黄柳杨 索学玲 雷都 龚启勇 梁繁荣 曾芳 《World Journal of Acupuncture-Moxibustion》 CSCD 2021年第1期6-15,共10页
Objective:To clarify altered whole brain functional connectivity of the anterior cingulate cortex(ACC)in functional dyspepsia(FD)patients,and then to explore cerebral influence of acupuncture with deqi treating for FD... Objective:To clarify altered whole brain functional connectivity of the anterior cingulate cortex(ACC)in functional dyspepsia(FD)patients,and then to explore cerebral influence of acupuncture with deqi treating for FD.Methods:Thirty-two FD patients and 35 healthy subjects(HS)were firstly scanned by the resting-state blood oxygenation level-dependent functional magnetic resonance imaging(BOLD-fMRI)to compare differences of ACC-based functional connectivity(FC).Then 32 FD patients were randomized to receive 20 sessions’acupuncture treatment with(n=16)and without deqi(n=16),as well as underwent functional magnetic resonance imaging(fMRI)scans after treatment.After group re-division according to deqi response,changes of ACC subregions-based resting-state FC(rsFC)were compared between the actual with and without deqi group.Two seeds with bilateral of each were selected as regions of interest(ROIs)of the ACC,including two from the dorsal ACC:S2(BA24)(x=±5,y=2,z=46,r=3.5 mm)and two from the pregenual ACC:17(BA24)(x=±5,y=38,z=6,r=3.5 mm).The clinical changes of the Nepean Dyspepsia Index(NDI)that measuring symptoms and quality of life(QOL)were also used to further assess the correlation with ACC subregions rsFC in FD patients.Results:Compared to HS,FD patients showed significantly increased ACC subregions rsFC with left fusiform gyrus,temporal cortex,hippocampus(HIPP)/amygdala,temporal pole,and right INS,superior occipital gyrus,and bilateral precuneus,superior parietal lobule(SPL),and decreased rsFC with left postcentral/precentral gyrus(PoG/PrG),supplementary motor area(SMA)and right cerebellum.32 FD patients which were then re-divided into the actual deqi group(n=16)and actual without deqi group(n=16).The decrease of the NDI symptom score(pre-pos)in the actual deqi group was significantly greater than that in the actual without deqi group(P<0.05).Among the two groups,the actual deqi group showed increased ACC subregions rsFC with right SMA and bilateral PrG/PoG,and decreased rsFC with right precuneus,middle occipital gyrus,bilateral posterior cingulate cortex(PCC),HIPP/paraHIPP,angular gyrus and SPL after treatment.In addition,the changed NDI QOL scores(pre-post)of the actual deqi group was significantly positively correlated with their Fisher’s transformed Z value of the altered ACC subregion(left I7)rsFC with right SPL(r=-0.597,P=0.04<0.05,FDR corrected P>0.05).Conclusion:The results tested the hypothesis that the advantage of deqi on efficacy is related to affecting the ACC subregions rsFC.It suggested that deqi might participate in the adaptive modulation of disrupted relationship between the ACC subregions and the default mode network(DMN). 展开更多
关键词 DEQI Functional dyspepsia ACC subregions RESTING-STATE Functional connectivity
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Molecular Dynamics Simulations and Experimental Investigations of Atomic Diffusion Behavior at Bonding Interface in an Explosively Welded Al/Mg Alloy Composite Plate 被引量:9
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作者 ting-ting zhang Wen-Xian Wang +3 位作者 Jun Zhou Xiao-Qing Cao Rui-Shan Xie Yi Wei 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第10期983-991,共9页
In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics(MD) simulations were conducted to investigate atomic diffusion behavior at b... In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics(MD) simulations were conducted to investigate atomic diffusion behavior at bonding interface in the AI/Mg composite plate. Corresponding experiments were conducted to validate the simulation results. The results show that diffusion coefficient of Mg atom is larger than that of A1 atom and the difference between these two coefficients becomes smaller with increasing collision velocity. The diffusion coefficient was found to depend on collision velocity and angle. It increases linearly with collision velocity when the collision angle is maintained constant at 10° and decreases linearly with collision angle when the collision velocity is maintained constantly at 440 m/s. Based on our MD simulation results and Fick's second law, a mathematical formula to calculate the thickness of diffusion layer was proposed and its validity was verified by relevant experiments. Transmission electron microscopy and energy-dispersive system were also used to investigate the atomic diffusion behavior at the bonding interface in the explosively welded 6061/AZ31B composite plate. The results show that there were obvious Al and Mg atom diffusion at the bonding interface,and the diffusion of magnesium atoms from magnesium alloy plate to aluminum alloy plate occurs much faster than the diffusion of aluminum atoms to the magnesium alloy plate. These findings from the current study can help to optimize the explosive welding process. 展开更多
关键词 Al/Mg composite plate Explosive welding Molecular dynamics simulation Atomic diffusionbehavior
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Heterologous expression and characterization of two chitinase 5 enzymes from the migratory locust Locusta migratoria 被引量:6
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作者 Ying-Long Li Hui-Fang Song +4 位作者 Xue-Yao zhang Da-Qi Li ting-ting zhang En-Bo Ma Jian-Zhen zhang 《Insect Science》 SCIE CAS CSCD 2016年第3期406-416,共11页
Insect chitinases are involved in degradation of chitin from the exoskeleton or peritrophic metrix ofmidgut. In Locusta migratoria, two duplicated Cht5s (LmCht5-1 and LmCht5-2) have been shown to have distinct molec... Insect chitinases are involved in degradation of chitin from the exoskeleton or peritrophic metrix ofmidgut. In Locusta migratoria, two duplicated Cht5s (LmCht5-1 and LmCht5-2) have been shown to have distinct molecular characteristics and biological roles. To explore the protein properties of the two LmCht5s, we heterologously expressed both enzymes using baculovirus expression system in SF9 cells, and characterized kinetic and carbohydrate-binding properties of purified enzymes. LmCht5-1 and LmCht5-2 exhibited similar pH and temperature optimums. LmCht5-1 has lower Km value for the oligomeric substrate (4MU-(GlcNAe)3), and higher Km value for the longer substrate (CM-Chitin- RBV) compared with LmCht5-2. A comparison of amino acids and homology modeling of catalytic domain presented similar TIM barrel structures and differentiated amino acids between two proteins. LmCht5-1 has a chitin-binding domain (CBD) tightly bound to colloidal chitin, but LmCht5-2 does not have a CBD for binding to colloidal chitin. Our results suggested both LmCht5- I and LmCht5-2, which have the critical glutamate residue in region II of catalytic domain, exhibited chitinolytic activity cleaving both polymeric and oligomeric substrates. LmCht5-1 had relatively higher activity against the oligomeric substrate, 4MU-(GlcNAc)3, whereas LmCht5-2 exhibited higher activity toward the longer substrate, CM-Chitin-RBE These findings are helpful for further research to clarit}g their different roles in insect growth and development. 展开更多
关键词 chitinase 5 enzyme kinetics heterologous expression Locusta migratoria
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Distribution and Risk Factors of Disability Attributed to Personality Disorders: A National Cross-sectional Survey in China 被引量:3
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作者 ting-ting zhang Yue-Qin Huang +1 位作者 Zhao-Rui Liu Hong-Guang Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第15期1765-1771,共7页
Background: Personality disorders can lead to some disability. However, little is known about the disability prevalence and function impairments. This study aimed to describe the disability prevalence attributed to p... Background: Personality disorders can lead to some disability. However, little is known about the disability prevalence and function impairments. This study aimed to describe the disability prevalence attributed to personality disorders, its distribution, impairments of daily activities and social functions, and risk factors in China. Methods: Using a descriptive and analytic epidemiological method, data from the Second China National Sample Survey on Disability in 2006 were analyzed. The disability prevalence attributed to personality disorders, its distribution in different people and regions, and risk factors were statistically calculated. Results: Respondents included 1,909,205 adults. The disability prevalence rate attributed to personality disorders in China was 5.9/100,000. The disability rate attributed to personality disorders of males was higher than that of females (P 0.012), while the rate of the unemployed was higher than that of the employed (P 〈 0.001 ). Furthermore, the rates of unmarried/divorced/widowed people and the illiterate population were higher than those of married and educated people (P 〈 0.001 ). Regarding the severity of disability attributable to personality disorders, mild disability accounted for a majority or 60% of the respondents. The data showed that disability mainly impaired respondents' ability to engage in daily activities, get along with people, and participate in social situations. According to the case-control study, marriage, employment, and higher education were protective factors of disability. Conclusions: The prevalence of disability attributed to personality disorders is low in China and always leads to mild disability. The distribution of disability attributed to personality disorders also varies in the Chinese population. 展开更多
关键词 Disability Prevalence EPIDEMIOLOGY Mental Disability Personality Disorders
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Silencing of transcription factor E93 inhibits adult morphogenesis and disrupts cuticle, wing and ovary development in Locusta migratoria 被引量:2
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作者 Xiao-Jian Liu Guo Jun +5 位作者 Xiao-Yu Liang Xue-Yao zhang ting-ting zhang Wei-Min Liu Jian-Zhen zhang Min zhang 《Insect Science》 SCIE CAS CSCD 2022年第2期333-343,共11页
Ecdysone-induced protein 93F(E93)plays important roles during the metamorphosis process in insects.In this study,a cDNA of the LmE93 gene was identified from the transcriptome of Locusta migratoria,which consists of t... Ecdysone-induced protein 93F(E93)plays important roles during the metamorphosis process in insects.In this study,a cDNA of the LmE93 gene was identified from the transcriptome of Locusta migratoria,which consists of the 3378-nucleotide open-reading frame(ORF)and encodes 1125 amino acids with helix–turn–helix(HTH)motifs.Reverse transcription quantitative polymerase chain reaction analysis revealed that LmE93 was highest expressed in ovary.The LmE93 expression level was markedly low from the 3rd to 4th instar nymphs,and greatly increased in 1-day-old 5th instar nymphs with a peak on middle nymphal days,then declined in the late nymphal days.Moreover,injected dsLmE93 into 4th and 5th instar nymphs greatly reduced LmE93 transcripts,respectively,and prevented the process of metamorphosis,causing supernumerary nymphal stages.Hematoxylin–eosin staining of the integument showed that the apolysis occurred in advance in 4th instar nymphs,and old cuticle degradation was decreased in dsLmE93-injected locusts of 5th instar nymphs.Smaller and no fully developed wings with reduced columns between the anterior and posterior regions were found in N6 and N7 supernumerary nymphs.In addition,the development of the ovary in dsLmE93-injected locusts was severely blocked,the yolk was almost not formed and there was no development of ovarioles.The results indicated that LmE93 play key roles in the metamorphosis,cuticle,wing and ovarian development of locusts. 展开更多
关键词 expression function Locusta migratoria RNA interference transcription factor E93
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