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Molecular Mechanism of Rice Necrotic Lesion for Optimized Yield and Disease Resistance
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作者 HOU Xinyue WANG Yuping +1 位作者 QIAN Qian REN Deyong 《Rice science》 SCIE CSCD 2024年第3期285-299,共15页
How to balance rice resistance and yield is an important issue in rice breeding.Plants with mutated necrotic lesion genes often have persistent broad-spectrum resistance,but this broad-spectrum resistance usually come... How to balance rice resistance and yield is an important issue in rice breeding.Plants with mutated necrotic lesion genes often have persistent broad-spectrum resistance,but this broad-spectrum resistance usually comes at the expense of yield.Currently,many necrotic lesion mutants in rice have been identified,and these genes are involved in disease resistance pathways.This review provides a detailed introduction to the characteristics,classification,and molecular mechanisms of necrotic lesion formation.Additionally,we review the molecular regulatory pathways of genes involved in rice disease resistance.Concurrently,we summarize the relationship between resistance and yield in rice using newly developed gene editing methods.We discuss a rational and precise breeding strategy to better utilize molecular design technology for breeding disease-resistant and high-yield rice varieties. 展开更多
关键词 RICE necrotic lesion regulation mechanism high yield high resistance
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Mechanism of hypothalamic paraventricular nucleus in regulating asthmatic attack 被引量:4
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作者 Jia Liu Rong Dong +1 位作者 Jian Xiao Nina Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第7期593-596,共4页
BACKGROUND:It has been confirmed that c-fos expression increased markedly in hypothalamic paraventricular nucleus(PVN)during asthmatic attack in rats,and PVN has extensive physiological functions,involving in the regu... BACKGROUND:It has been confirmed that c-fos expression increased markedly in hypothalamic paraventricular nucleus(PVN)during asthmatic attack in rats,and PVN has extensive physiological functions,involving in the regulation of respiratory system,etc.OBJECTIVE:To observe the alteration of electroencephalogram(EEG)and power spectra in PVN during the asthmatic attack,and the alteration of lung function and diaphragmatic muscle discharge after bilateral PVN lesion in asthmatic rats.DESIGN:A randomized control study.SETTING:Laboratory of Physiology and Pharmacology,School of Basic Medical Sciences,Southeast University.MATERIALS:Forty-eight male adult SD rats of 260-300 g were used.The rats were randomly divided into 6 groups(n=8):control group,asthma group,electrolytic lesion of PVN group,KA-induced lesion of PVN group,sham electrolytic lesion of PVN group and sham kainic acid(KA)-induced lesion of PVN group.KA,chicken ovalbumin and aluminum hydroxide were purchased from American Sigma Company.Bordetella pertussis vaccine(Institute of Biological Products of Shanghai);stereotaxic apparatus(JiangwanⅡ,China);lesion-producing device(YC-2 programmable stimulato,Chengdu Instrument Company);MD2000 signal processing system(Nanjing Medical School);data acquisition system(RM6240B,Chengdu Instrument Company).METHODs:The experiments were carried out in the Laboratory of Physiology and Pharmacology,School of Basic Medical Sciences,Southeast University from January to August in 2006.①Rats except for control group were sensitized with an intraperitoneal injection of 100 mg chicken ovalbumin and 100 mg aluminum hydroxide and Bordetella pertussis vaccine containing 5×10^(9) heat-killed in 1 mL of sterile saline.From the fifteenth to seventeenth days rats received three times aerosolized ovalbumin challenge.In rats of the control group and asthma group three steel electrodes were placed into the left PVN(AP-1.8 mm,LR 0.4 mm,OH-7.9 mm),parietal cortex and subcutaneous tissue in lower limb.Lung function tests were carried out simultaneously.Small holes were drilled in the skull to introduce a concentric bipolar electrode in the direction of the PVN in order to perform electrolytic lesion.The electrodes were connected to a lesion-producing device and a current of 1.0-1.5 mA was passed over a period of 10-15 s on each side of the PVN.The rats received 0.5μg/0.5μL of KA in phosphate buffer(0.1 mol/L,pH 7.4),and the speed of infusion was 0.1μL per minute in order to perform KA-induced lesion of PVN.②Three days after operation of lesion,lung function tests were carried out.All the electrode and transducer were connected with data acquisition system.This technique yielded airway resistance(Raw),dynamic compliance(Cdyn),the expiratory time(Te)/the inspiratory time(Ti),minute ventilation volume(MVV),EMGdi frequency and EMGdi integral.③The differences of the measurement data were compared using the t test.MAIN OUTCOME MEASURES:①The alteration of EEG and power spectrum of PVN during asthmatic attack in sensitized rats;②The effects of electrolytic lesion or KA-induced lesion of PVN on lung function in asthmatic rats.RESULTS:All the 48 rats were involved in the analysis of results.①Alteration of EEG and power spectrum:Five minutes after injection of ovalbumin into caudal vena,the breathing rate of the rat was obviously speeded up and the total power spectrum was increased[(18476.71±2140.94),(13838.75±2983.26)mV^(2),P<0.01],the percentage of theδpower andθpower decreased significantly(P<0.01),while the percentage ofαpower andβ1 power were enhanced(P<0.05,0.01).Ten minutes after injection,the EEG power spectrum of PVN further shifted rightward,the total power gradually increased(P<0.01)which suggesting that the intensive hypersynchrony activities of PVN neurons.The percentage ofδpower was decreased significantly(P<0.01),but theα,β1 andβ2 were increased(P<0.01).Twenty-five minutes later,the breathing movements became steady,and the EEG power spectrum of PVN returned to the control level step by step.②The alteration of lung function was detected during asthmatic attack after electrolytic lesion or KA-induced lesions of PVN respectively.It was found that EMGdi frequency,Te/Ti and RL were all decreased(P<0.01),EMGdi integral,MVV and Cdyn were all enhanced(P<0.01),while there were no significant changes in the sham surgery group(P>0.05).CONCLUSION:The excitability of PVN is increased during the asthmatic attack.PVN plays a key role in the regulation of asthma.Both electrolytic and KA lesions of PVN can significantly relieve the asthmatic symptoms of rats,and improve their lung function. 展开更多
关键词 PVN mechanism of hypothalamic paraventricular nucleus in regulating asthmatic attack
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Molecular regulation mechanism of oocyte maturation in beef cattle
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作者 BINWU BAO JINPENG WANG +4 位作者 YANXIA LI FEN FENG ZHONGXIANG JI ZHUOMA LUORENG XINGPING WANG 《BIOCELL》 SCIE 2023年第7期1509-1518,共10页
Bovine oocytes are one of the indispensable cells in cattle reproduction and have become a research hot spot in cattle reproduction in recent years.The maturation process of oocytes is mainly regulated by enzymes,horm... Bovine oocytes are one of the indispensable cells in cattle reproduction and have become a research hot spot in cattle reproduction in recent years.The maturation process of oocytes is mainly regulated by enzymes,hormones,cytokines,and other molecules.The factors affecting cattle oocyte maturation have been previously studied to clarify the molecular mechanisms of cattle oocyte maturation.In this review article,phospholipid protein-3-kinase/protein kinase B,mitogen-activated protein kinase/extracellular signal-regulated kinase,Janus kinase/signal transducer and activator of transcription,epidermal growth factor receptor/extracellular signal-regulated kinase,and other signaling pathways related to oocyte maturation are discussed.In addition,the molecular mechanisms of some coding genes(JY-1,FGF-10,CDC20,etc.)and non-coding genes(miRNA,lncRNA,and circRNA)regulating oocyte maturation have been reviewed to provide new ideas for high reproductive performance molecular breeding of high-quality cattle. 展开更多
关键词 Signaling pathway Bovine reproduction Regulation mechanism GENE OOCYTE
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Response Mechanism of Plants to Drought Stress
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作者 Pei GAO Yuhua MA 《Plant Diseases and Pests》 CAS 2023年第5期30-34,共5页
Drought stress is an important factor affecting plant growth and development.It will provide a theoretical basis for cultivating new stress-resistant varieties and improving water utilization rate of plants by studyin... Drought stress is an important factor affecting plant growth and development.It will provide a theoretical basis for cultivating new stress-resistant varieties and improving water utilization rate of plants by studying the regulation mechanism of osmotic adjustment and water transportation under drought stress,and understanding the physiological and biochemical characteristics and stress resistance mechanism. 展开更多
关键词 Plant gene Drought stress Regulation mechanism Osmotic adjustment substance Water transportation
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Preparation of Manganese Oxide and Its Adsorption Properties
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作者 贺跃 王海峰 +4 位作者 YANG Pan WANG Song CHEN Xiaoliang YANG Chunyuan 王家伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1031-1040,共10页
The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of ... The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of different oxidants on the morphology,phase composition,surface properties and specific surface area of manganese oxides were investigated.The experimental results show that the diameter of manganese oxide particles prepared with H_(2)O_(2)is the smallest,about 50 nm,and the specific surface area is the largest,63.8764 m^(2)/g.It has the advantages of abundant surface hydroxyl groups,no introduction of other impurities and large adsorption potential.It is most suitable to be used as an oxidant for oxidizing manganese sulfate solution to prepare manganese oxide by in-situ oxidation.Nano manganese oxide prepard by H_(2)O_(2)in-situ oxidation method is used as adsorbent to adsorb cobalt and nickel impurities in manganese sulfate.When the reaction pH is 6,the reaction time is 30min and the amount of adsorbent is 1.0 g,the adsorption rates of cobalt and nickel impurities in 100ml manganese sulfate solution are 97.59%and 97.67%,respectively.The residual amounts of cobalt and nickel meet the industrial process standard of first-class products(Co,Ni w/%≤0.005)of high-purity manganese sulfate(Hg/t4823-2015)for batteries.The study plays a guiding role in the preparation and regulation of manganese oxide,and provides a new method with high efficiency,purity and adsorbent availability for the preparation of high-purity manganese sulfate solution. 展开更多
关键词 manganese oxide in situ oxidation ADSORBENT regulation mechanism PHYSICAL chemical properties
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Membrane tension evolution and mechanical regulation of melittin-induced membrane poration
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作者 Wanting Zhang Rong Xu +3 位作者 Wendong Ma Zhao Lin Kai Yang Bing Yuan 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期465-475,共11页
Membrane tension plays a crucial role in various fundamental cellular processes,with one notable example being the T cell-mediated elimination of tumor cells through perforin-induced membrane perforation by amplifying... Membrane tension plays a crucial role in various fundamental cellular processes,with one notable example being the T cell-mediated elimination of tumor cells through perforin-induced membrane perforation by amplifying cellular force.However,the mechanisms governing the regulation of biomolecular activities at the cell interface by membrane tension remain elusive.In this study,we investigated the correlation between membrane tension and poration activity of melittin,a prototypical pore-forming peptide,using dynamic giant unilamellar vesicle leakage assays combined with flickering tension analysis,molecular dynamics simulations,and live cell assays.The results demonstrate that an increase in membrane tension enhances the activity of melittin,particularly near its critical pore-forming concentration.Moreover,peptide actions such as binding,insertion,and aggregation in the membrane further influence the evolution of membrane tension.Live cell experiments reveal that artificially enhancing membrane tension effectively enhances melittin’s ability to induce pore formation and disrupt membranes,resulting in up to a ten-fold increase in A549 cell mortality when exposed to a concentration of 2.0-μg·mL^(-1)melittin.Our findings elucidate the relationship between membrane tension and the mechanism of action as well as pore-forming efficiency of melittin,while providing a practical mechanical approach for regulating functional activity of molecules at the cell-membrane interface. 展开更多
关键词 membrane tension mechanical regulation membrane poration giant unilamellar vesicle leakage assay
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Investigation on mechanical properties regulation of rock-like specimens based on 3D printing and similarity quantification
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作者 Duanyang Zhuang Zexu Ning +3 位作者 Yunmin Chen Jinlong Li Qingdong Li Wenjie Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期573-585,共13页
3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properti... 3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properties of 3D-printed specimens to make them proportionally similar to natural rocks.This study investigates mechanical properties of 3D-printed rock analogues prepared by furan resin-bonded silica sand particles.The mechanical property regulation of 3D-printed specimens is realized through quantifying its similarity to sandstone,so that analogous deformation characteristics and failure mode are acquired.Considering similarity conversion,uniaxial compressive strength,cohesion and stress–strain relationship curve of 3D-printed specimen are similar to those of sandstone.In the study ranges,the strength of 3D-printed specimen is positively correlated with the additive content,negatively correlated with the sand particle size,and first increases then decreases with the increase of curing temperature.The regulation scheme with optimal similarity quantification index,that is the sand type of 70/140,additive content of 2.5‰and curing temperature of 81.6℃,is determined for preparing 3D-printed sandstone analogues and models.The effectiveness of mechanical property regulation is proved through uniaxial compression contrast tests.This study provides a reference for preparing rock-like specimens and engineering models using 3D printing technology. 展开更多
关键词 3D printing Mechanical property regulation Similarity quantification Rock analogue SANDSTONE
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Study on the Whole Process Simulation and Regulation Mechanism of Urban Green Ecological Rainwater Drainage System
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作者 Lu Cao Li Huang +1 位作者 Penghe Zhao Yuling Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第11期787-803,共17页
In view of the frequent waterlogging caused by rapid urbanization and the public’s dissatisfaction with the drainage system,the article based on the concept of the green ecological drainage system,constructed the urb... In view of the frequent waterlogging caused by rapid urbanization and the public’s dissatisfaction with the drainage system,the article based on the concept of the green ecological drainage system,constructed the urban green ecological drainage comprehensive simulation research system,and quickly evaluated pipe network operation and surface water of an industrial park under typical rainfall conditions.The results showed that the drainage capacity of the designed green ecological rainwater drainage system reached 100%,and there was no ponding phenomenon,which indicated that the green ecological rainwater drainage system could effectively solve the practical problems of urban drainage.The green ecological rainwater comprehensive simulation research system had good adaptability.The research results provided the scientific theoretical basis and reference significance for planning,designing,constructing,operating,and managing urban rainwater system scientifically and systematically. 展开更多
关键词 Urban waterlogging rainwater pipe network green ecological drainage system rapid evaluation model regulation mechanism
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Acetylation as a mechanism that regulates axonal regeneration
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作者 Shen Lin George M.Smith 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1034-1036,共3页
The capacity for adult axons to regenerate after injury is diminished compared with developing axons.In the case of central nervous system(CNS)axons,injury causes a total failure to regenerate.This failure is due to... The capacity for adult axons to regenerate after injury is diminished compared with developing axons.In the case of central nervous system(CNS)axons,injury causes a total failure to regenerate.This failure is due to both the intrinsic developmental decrease in growth capacity and the extrinsic inhibitory environment formed because of the injury. 展开更多
关键词 GENE HDAC Acetylation as a mechanism that regulates axonal regeneration
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Regulation of vegetation pattern on the hydrodynamic processes of erosion on hillslope in Loess Plateau,China 被引量:1
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作者 Guo-Qiang Yu Qian Wang +1 位作者 Li-Feng Zhu Xia Zhang 《Journal of Groundwater Science and Engineering》 2023年第1期4-19,共16页
As vegetation are closely related to soil erosion,hydrodynamic parameter changes under various vegetation pattern conditions can be used as an important basis for the research of the soil erosion mechanism.Through ups... As vegetation are closely related to soil erosion,hydrodynamic parameter changes under various vegetation pattern conditions can be used as an important basis for the research of the soil erosion mechanism.Through upstream water inflow experiments conducted on a loess hillslope,how the vegetation pattern influences the hydrodynamic processes of sediment transport was analyzed.The results show that the placement of a grass strip on the lower upslope can effectively reduce runoff erosion by 69%,relying on the efficiency of regulated hydrodynamic process.The effective location of grass strip for hillslope alleviating erosion is on the lower part of the upslope,mainly due to the grass strip measure used to regulate the hydrodynamic system.As a result,the underlying surface runoff resistance is increased by 5 times,runoff shear stress is decreased by more than 90%,and runoff power decreased by over 92%.The measure greatly separates the scouring energy of surface runoff that acts on the slope soil.Therefore,the use of grass strips effectively decreases the energy of runoff flowing along the slope,eliminating soil erosion to a great extent and thereby achieving a better regulation of hydrodynamic processe. 展开更多
关键词 Soil erosion Grass strip Scouring experiment Sediment transport regulating mechanism Loess Plateau
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Grain Macro-Control Mechanism Research
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《International English Education Research》 2014年第10期71-73,共3页
this paper based on the food security, the food the macroeconomic regulation and control of the operation mechanism of the general theory, focus on the China's grain macroeconomic regulation and control mechanism, th... this paper based on the food security, the food the macroeconomic regulation and control of the operation mechanism of the general theory, focus on the China's grain macroeconomic regulation and control mechanism, the concept of grain macroeconomic regulation and control mechanism, the grain circulation macroeconomic regulation and control tool application, grain circulation macroeconomic regulation and control system, the problem of grain circulation system, food price formation mechanism. Through the research set up grain control of the operation mechanism of general theory. 展开更多
关键词 macroeconomic management food economy grain macro-control mechanism regulation and
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Electrolytes additives for Zn metal anodes:regulation mechanism and current perspectives
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作者 Yu-Zhe Zhang Huai-Sheng Ao +6 位作者 Qi Dong Shao-Jie Zhang Zhi-Guo Hou Na-Na Wang Xue-Song Xie Jian Rong Zhong-Yu Li 《Rare Metals》 SCIE EI CAS CSCD 2024年第9期4162-4197,共36页
With distinct advantages such as high gravimetric and volumetric capacity(5855 mAh·cm^(-3)and 820mAh·g^(-1)),low redox potential(-0.762 V vs.standard hydrogen electrode(SHE)),high abundance,low toxicity and ... With distinct advantages such as high gravimetric and volumetric capacity(5855 mAh·cm^(-3)and 820mAh·g^(-1)),low redox potential(-0.762 V vs.standard hydrogen electrode(SHE)),high abundance,low toxicity and intrinsic safety of Zn metal anode,Zn-ion batteries have become a potential alternative to Li-ion batteries.However,several challenges still need to be addressed prior to the practical applications of Zn-ion batteries,such as dendrite growth during Zn plating/stripping and interfacial side reactions on the Zn surface.Such issues can be addressed by introducing additives to regulate the components and structures of the electrolyte.In this review,we systematically discussed the core issues of metallic Zn anodes and comprehensively summarized a novel perspective of the regulation mechanism of inhibiting dendrite growth or interfacial side reactions in Zn anodes by introducing additives into aqueous electrolytes.Furthermore,some discussions and prospects for aqueous Zn ion batteries(AZIBs)are presented for future research. 展开更多
关键词 Electrolyte additives Zn metal anode Regulation mechanism Current perspectives AZIBs
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Molecular Mechanisms Regulating Rapid Stress Signaling Networks in Arabidopsis 被引量:11
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作者 Justin W. Walley Katayoon Dehesh 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第4期354-359,共6页
As sessile organisms plants must ronmental conditions. To survive cope with ever changing enviplants have evolved elaborate mechanisms to perceive and rapidly respond to a diverse range of abiotic and biotic stresses.... As sessile organisms plants must ronmental conditions. To survive cope with ever changing enviplants have evolved elaborate mechanisms to perceive and rapidly respond to a diverse range of abiotic and biotic stresses. Central to this response is the ability to modulate gene expression at both the transcriptional and posttranscriptional levels. This review will focus on recent progress that has been made towards understanding the rapid reprogramming of the transcriptome that occurs in response to stress as well as emerging mechanisms underpinning the reprogramming of gene expression in response to stress, 展开更多
关键词 Molecular mechanisms regulating Rapid Stress Signaling Networks in Arabidopsis CAF
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The soybean PLATZ transcription factor GmPLATZ17 suppresses drought tolerance by interfering with stress-associated gene regulation of GmDREB5 被引量:2
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作者 Juanying Zhao Lei Zheng +7 位作者 Jitong Wei Yixuan Wang Jun Chen Yongbin Zhou Ming Chen Fengzhi Wang Youzhi Ma Zhao-Shi Xu 《The Crop Journal》 SCIE CSCD 2022年第4期1014-1025,共12页
Plant AT-rich sequence and zinc binding(PLATZ)transcription factors are a class of plant specific zincdependent DNA-binding proteins that function in abiotic stress response and plant development.In this study,31 GmPL... Plant AT-rich sequence and zinc binding(PLATZ)transcription factors are a class of plant specific zincdependent DNA-binding proteins that function in abiotic stress response and plant development.In this study,31 GmPLATZ genes were identified in soybean.GmPLATZ17 was down-regulated by drought and exogenous abscisic acid.Transgenic Arabidopsis and soybean hairy roots overexpressing GmPLATZ17 showed drought sensitivity and inhibition of stress-associated gene transcription.In contrast,suppressed expression of GmPLATZ17 led to increased drought tolerance in transgenic soybean hairy roots.The GmPLATZ17 protein was verified to interact physically with the GmDREB5 transcription factor,and overexpression of GmDREB5 increased drought tolerance in soybean hairy roots.Interaction of GmPLATZ17 with GmDREB5 was shown to interfere with the DRE-binding activity of GmDREB5,suppressing downstream stress-associated gene expression.These results show that GmPLATZ17 inhibits drought tolerance by interacting with GmDREB5.This study sheds light on PLATZ transcription factors and the function of GmPLATZ17 in regulating drought sensitivity. 展开更多
关键词 SOYBEAN PLATZ transcription factor Protein interaction Regulation mechanism Drought response
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Controllable blood–brain barrier(BBB)regulation based on gigahertz acoustic streaming 被引量:1
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作者 Hang Qi Shuaihua Zhang +2 位作者 Jiaxue Liang Shan He Yanyan Wang 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第4期1-7,共7页
The blood–brain barrier(BBB)is a structural and functional barrier necessary for brain homeostasis,and it plays an important role in the realization of neural function and in protecting the brain from damage by circu... The blood–brain barrier(BBB)is a structural and functional barrier necessary for brain homeostasis,and it plays an important role in the realization of neural function and in protecting the brain from damage by circulating toxins and pathogens.However,the extremely dense BBB also severely limits the transport of molecules across it,which is a great hindrance to the diagnosis and treatment of central nervous system(CNS)diseases.This paper reports a new method for controllable opening of the BBB,based on the gigahertz acoustic streaming(AS)generated by a bulk acoustic wave resonant device.By adjusting the input power and working distance of the device,AS with tunable flow rate can be generated to disrupt tight junction proteins(TJs)between endothelial cells.The results obtained with this method show that the gigahertz AS promotes the penetration of dextran molecules with different molecular weights across the BBB.This work provides a new platform for studying the mechanical regulation of BBB by fluid shear forces and a new method for improving the efficiency of drug delivery. 展开更多
关键词 Blood–brain barrier Mechanical regulation Drug delivery Bulk acoustic wave Acoustic streaming
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The regulation mechanism and heat transfer enhancement of composite mixed paraffin and copper foam phase change materials 被引量:4
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作者 YANG HanXue ZHANG GuanHua +4 位作者 DOU BinLin CUI GuoMin YAN XiaoYu LU Wei WANG ZiLong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第8期2346-2360,共15页
Phase change materials(PCMs)have remarkable energy storage capacity and promising applications in the field of thermal control of electronic products.The problem of thermal property improvement and heat transfer of PC... Phase change materials(PCMs)have remarkable energy storage capacity and promising applications in the field of thermal control of electronic products.The problem of thermal property improvement and heat transfer of PCMs in metal-foam heatsinks is an important task for thermal management of electronic components.Mixed paraffin samples were prepared by mixing appropriate proportions of paraffin(mass)at various temperatures.Differential scanning calorimetry analysis revealed that the maximum enthalpy of 206.3 J/g is obtained by mixing 20%of 17°C liquid paraffin and 80%of 29℃ solid paraffin.Heating and cooling cycling tests revealed that mixed paraffin exhibits excellent thermal stability and that the regulation method marginally affects thermal stability.Moreover,composites were prepared by embedding PCM into a copper foam by melt impregnation.The thermal conductivity of the composites increased to 4.35 W/(m K),corresponding to 20 times its original value.In addition,density functional theory and experimental results were in good agreement,indicating that the regulation method is practical and effective. 展开更多
关键词 phase change materials regulation mechanism temperature dependence thermal conductivity heat transfer enhancement
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Study on the morphological regulation mechanism of hollow silica microsphere prepared via emulsion droplet template 被引量:1
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作者 Chu Zhao Zhiqing Ge +4 位作者 Zhuoni Jiang Shuo Yan Jingjing Shu Mozhen Wang Xuewu Ge 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期575-579,共5页
The morphology regulation of hollow silica microspheres is significant for their properties and applications. In this paper, hollow silica microspheres were formed through the hydrolysis and condensation reaction of t... The morphology regulation of hollow silica microspheres is significant for their properties and applications. In this paper, hollow silica microspheres were formed through the hydrolysis and condensation reaction of tetraethyl orthosilicate(TEOS) at the interface of the emulsion droplet templates composed of liquid paraffin and TEOS, followed by dissolving paraffin with ethanol. The effects of various factors including the emulsifier structure and content, TEOS content, catalyst type, and the ethanol content in the continuous water phase on the particle size, shell thickness and morphology of the prepared hollow silica microspheres were studied in detail. The results show that the diffusion and contact of TEOS and water molecules as well as the hydrolysis condensation reaction of TEOS at the oil-water interface are two critical processes for the synthesis and morphological regulation of hollow silica microspheres. Cationic emulsifier with a hydrophobic chain of appropriate length is the prerequisite for the successful synthesis of hollow silica microspheres. The ethanol content in water phase is the dominant factor to determine the average diameter of hollow microspheres, which can vary from 96 nm to 660 nm with the increase of the volume ratio of alcohol-water from 0 to 0.7. The silica wall thickness varies with the content and the hydrophobic chain length of the emulsifier, TEOS content, and the activity of the catalyst. The component of the soft template will affect the morphology of the silica wall. When the liquid paraffin is replaced by cyclohexane, hollow microspheres with fibrous mesoporous silica wall are fabricated. This work not only enriches the basic theory of interfacial polymerization in the emulsion system, but also provides ideas and methods for expanding the morphology and application of hollow silica microspheres. 展开更多
关键词 Hollow silica microspheres Emulsion template Morphology regulation mechanism Interfacial polymerization
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A Study on the Molecular Switch of Gene Expression of the Mouse Heart Nuclear DNA Fragments
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作者 袁明秀 JIN +6 位作者 Rui Niu Weiran Chen Zhijun Zhang Zhihong 《High Technology Letters》 EI CAS 2001年第4期1-7,共7页
It is observed by in situ stain that LDH (1 5) ...nNAD + can probably enter the nucleopore and can be bound bound specifically with the genes that encode them. During the in vitro expression, the dilution of heart nuc... It is observed by in situ stain that LDH (1 5) ...nNAD + can probably enter the nucleopore and can be bound bound specifically with the genes that encode them. During the in vitro expression, the dilution of heart nuclear DNA fragments could enhance the expression activity of LDH/DNA and the amount of expressed LDH (1 5) is in proportion to the amount of dissociable LDH (1 5) on the LDH/DNA. With the integration of 14C Leu to the proteins, it is also observed that the addition of LDH (1 5) ...nNAD + can suppress the in vitro expression activity of LDH/DNA. AFM observation shows that the regulation sequence at the both ends of active genes may be bound with such active factors as proteins encoded by the genes which probably is the main molecular switch of gene expression and regulation we have been always searching for. Our work shows the prospective application of the combination of AFM and isotope labeling in the research of biological reaction. 展开更多
关键词 Molecular switch of gene expression Positive and negative feedback regulation mechanism Gene expression and regulation AFM
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Application of Green Roof in Relieving Urban Waterlogging: A Review
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作者 LIU Li LIU Xiaoqing 《Journal of Landscape Research》 2017年第6期74-76,80,共4页
Green roof plays a critical role in regulating roof runoff by reducing runoff, delaying runoff generation, reducing runoff peak flow and improving runoff water quality effectively. On the basis of introducing signific... Green roof plays a critical role in regulating roof runoff by reducing runoff, delaying runoff generation, reducing runoff peak flow and improving runoff water quality effectively. On the basis of introducing significance and role of green roof, this paper reviewed domestic and international researches on the green roof's control over roof runoff, and analyzed the factors that influence the control of green roof over the runoff, so as to provide a theoretical support and method for the construction of green roofs in urban districts. 展开更多
关键词 Green roof Urban waterlogging Stormwater runoff Regulation mechanism
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Identification of LepA as PPIase reveals a common molecular mechanism of translational GTPases regulating L11 switch on the ribosome
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作者 Yan Qin Institute of Biophysics, Chinese, 15 Datun Road, Chaoyang District, Beijing, 100101, China 《生物物理学报》 CAS CSCD 北大核心 2009年第S1期226-226,共1页
LepA, the highly conserved translational GTPase (trGTPase), triggers one-codon back-movement of the elongating ribosome. Here we identify a new enzymatic activity
关键词 PPIASE Identification of LepA as PPIase reveals a common molecular mechanism of translational GTPases regulating L11 switch on the ribosome
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