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Synergistic regulation of drought-responsive genes by transcription factor OsbZIP23 and histone modification in rice

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Journal of Integrative Plant Biology 2020年第6期62卷 723-729页

作者： Wei Zong jun yang Jie fu Lizhong Xiong National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China

Thousands of differentially expressed genes(DEGs)have been identified in rice under drought stress conditions.However,the regulatory mechanism of these DEGs remains largely unclear.Here,we report an interplay between histone H3K4me3 modification and transcription factor Osb ZIP23 in the regulation of a dehydrin gene cluster under drought stress conditions in rice.When the H3K4me3 modification level was increased,the dehydrin gene expression levels were increased,and the binding levels of Osb ZIP23 to the promoter of the dehydrin genes were also enhanced.Conversely,the H3K4me3 modification and dehydrin gene expression levels were downregulated in the osbzip23 mutant under drought stress conditions.Our study uncovers a collaboration between transcription factor and H3K4me3 modification in the regulation of droughtresponsive genes,which will help us to further understand the gene regulation mechanism under stress conditions in plants.

关键词： responsive conditions. drought

Nonlinearity analysis of piezoelectric micromachined ultrasonic transducers based on couple stress theory

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Acta Mechanica Sinica 2012年第1期28卷 104-111页

作者： Xin Kang Fu-Jun Yang Xiao-Yuan He Department of Applied Mechanics Nanjing University of Science and Technology210094 NanjingChina Department of Mechanical and Aeronautical Engineering University of CaliforniaDavis95616US Institute of Engineering Mechanics Southeast University210096 NanjingChina

This paper studies the static deformation behavior of a piezoelectric micromachined ultrasonic transducer （PMUT） actuated by a strong external electric field. The transducer membrane consists of a piezoelectric layer, a passive layer and two electrode layers. The nonlinearities of the piezoelectric layer caused by electrostriction under a strong electric field are analyzed. Because the thickness of the transducer membrane is on the microscale, the size dependence of the deformation behavior is evaluated using the couple stress theory. The results show that the optimal ratio of the top electrode diameter and the membrane diameter is around 0.674. It is also found that this optimal value does not depend on any other parameters if the thicknesses of the two electrodes are negligible compared with those of the piezo- electric and passive layers. In addition, the nonlinearities of the piezoelectric layer will become stronger along with the increase of the electric field, which means that softening of the membrane stiffness occurs when a strong external electric field is applied. Meanwhile, the optimal thickness ratio for the passive layer and the piezoelectric layer is not equal to 1.0 which is usually adopted by previous researchers. Because there exists size dependence of membrane deforma-tion, the optimal value of this thickness ratio needs to be greater than 1.0 on the microscale.

关键词： Piezoelectric micromachined ultrasonic trans- ducer （PMUT） Couple stress theory Static deformation - Nonlinearity analysis

Familial mitochondrial encephalomyopathy,lactic acidosis,and stroke-like episode syndrome:Three case reports

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World Journal of Clinical Cases 2022年第27期10卷 9945-9953页

作者： Xiao yang Le-jun fu Department of Medical Imaging Tianjin Huanhu HospitalTianjin 300350China

BACKGROUND Mitochondrial encephalomyopathy(ME)is a multisystem metabolic disease that primarily affects the central nervous system and skeletal muscle.It is caused by mutations in mitochondrial or nuclear DNA,resulting in abnormal mitochondrial structure and function and insufficient ATP synthesis.The most common subtype is mitochondrial encephalomyopathy,lactic acidosis,and stroke-like episode(MELAS)syndrome.In recent years,reports of MELAS syndrome have increased but familial cases are rare.CASE SUMMARY We report a case of familial MELAS syndrome.Cases 2 and 3 are sisters and case 1 is their nephew.All are short in stature and showed stroke-like episodes with rapid onset and no obvious symptoms such as paroxysmal headache,aphasia,or blurred vision.After admission,blood lactate levels were significantly higher than normal.The patients underwent magnetic resonance imaging of the head.Cases 1 and 2 were considered to have ME,whereas case 3 was considered to have a space-occupying lesion in the left temporal lobe.Pathological evaluation showed no obvious tumor cells in the brain lesions of case 3.Muscle biopsy or genetic test results were consistent with ME.The patients were diagnosed with MELAS syndrome and their symptoms improved with intravenous infusions of coenzyme Q10,coenzyme A,vitamin B,and vitamin C.At the 6 mo follow-up,there was no recurrence or progression.CONCLUSION When a patient has MELAS syndrome,familial MELAS syndrome should be considered if related family members have similar symptoms.

关键词： Mitochondrial encephalomyopathy Magnetic resonance imaging Genetic testing Pathological results Case report

A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection

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Fluid Dynamics & Materials Processing 2024年第3期20卷 537-546页

作者： Jiangshuai Wang Chuchu Cai Pan fu jun Li Hongwei yang Song Deng School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhouChina CNPC Research Institute of Engineering Technology Co. Ltd.BeijingChina National Engineering Research Center for Oil&Gas Drilling and Completion Technology BeijingChina College of Petroleum Engineering China University of Petroleum(Beijing)BeijingChina College of Petroleum Karamay CampusChina University of Petroleum(Beijing)BeijingChina

Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore pressure.In this study,a new heat transfer model is proposed by which the variable mass flow is properly taken into account.Using this model,the effects of the main factors influencing the wellbore temperature are analyzed.The results indicate that at the position where the separation injection device is installed,the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres,and the temperature drop of the fluid in the annulus also decreases.In addition,a lower separation efficiency of the device,a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus,thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling.

关键词： Multi-gradient drilling wellbore temperature hydrate separate injection device variable mass

Influence of Microcirculatory Dysfunction on Myocardial Injury after Cardiopulmonary Resuscitation

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Biomedical and Environmental Sciences 2022年第4期35卷 334-344页

作者： yang jun DONG Gui Juan WANG Hong Wei ZHAO Xin WANG fu jun ZHANG Jian GUO Shu Bin Emergency Medicine Clinical Research Center of Beijing Chaoyang Hospital Capital Medical UniversityBeijing Key Laboratory of Cardiopulmonary Cerebral ResuscitationBeijing 100020China

Objective This study aimed to examine the effects of microcirculatory dysfunction and 654-1intervention after cardiopulmonary resuscitation on myocardial injury.Methods Landrace pigs were divided into a sham operation group(S group,n=6),ventricular fibrillation control group(VF-C group,n=8)and 654-1 intervention group(VF-I group,n=8).Hemodynamics was recorded at baseline,at recovery of spontaneous circulation(ROSC),and 1 h,2 h,4h and 6 h thereafter.Sidestream dark field(SDF)technology was used to evaluate and monitor the microcirculation flow index,total vessel density,perfusion vessel ratio,De-Backer score,and perfusion vessel density in animal viscera at various time points.Results After administration of 654-1 at 1.5 h post-ROSC,the hemodynamics in the VF-I group,as compared with the VF-C group,was significantly improved.The visceral microcirculation detected by SDF was also significantly improved in the VF-I group.As observed through electron microscopy,significantly less myocardial tissue injury was present in the VF-I group than the VF-C group.Conclusion Administration of 654-1 inhibited excessive inflammatory by improving the state of visceral microcirculation.

关键词： Cardiopulmonary resuscitation Post-cardiac arrest syndrome Microcirculation dysfunction Myocardial injury Anisodamine hydrobromide(654-1)

Improved Properties of Aromatic Polyamide Tape-casting Films

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Chinese Journal of Polymer Science 2020年第12期38卷 1345-1354页

作者： fu-Lin Liu Jjian-jun He Hai-Xia yang Shi-Yong yang Laboratory of Advanced Polymer Materials Institute of ChemistryChinese Academy of SciencesBejing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049 China

A convenient tape-casting method was applied to prepare high performance aromatic polyamide(PA)films based on Technora®.During the polycondensation,CaO was introduced to improve the solubility of the PA resin,and the generated halides were totally removed from the film via a simple water bath,without leaving any defects in PA films.The factors of processing temperature and immersion time had been systematically investigated,and the experimental results demonstrated that both of them had impressive impacts on aggregation state and comprehensive properties of the PA film.It was suggested that immersion in water for more than 1 min and baking below 300℃ for 10 min were the optimal conditions for the thermal,tensile,tear,and optical properties to be in the best equilibrium.The resultant PA films integrated outstanding film-forming ability and excellent general performance,especially the tensile property and tear resistance.

关键词： Tape-casting Aromatic polyamide film Solubility Aggregation state Tensile property Tear resistance

Combustion synthesis of bulk nanocrystalline iron alloys

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Progress in Natural Science:Materials International 2016年第1期26卷 13-23页

作者： Licai fu jun yang Weimin Liu College of Materials Science and Engineering Hunan University State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

The controlled synthesis of large-scale nanocrystalline metals and alloys with predefined architecture is in general a big challenge, and making full use of these materials in applications still requires greatly effort. The combustion synthesis technique has been successfully extended to prepare large-scale nanocrystalline metals and alloys, especially iron alloy, such as Fe C, Fe Ni, Fe Cu, Fe Si, Fe B, Fe Al, Fe Si Al, Fe Si B, and the microstructure can be designed. In this issue, recent progress on the synthesis of nanocrystalline metals and alloys prepared by combustion synthesis technique are reviewed. Then, the mechanical and tribological properties of these materials with microstructure control are discussed.

关键词： Combustion synthesis Nanocrystalline Mechanical behavior Tribological properties

Numerical and Experimental Investigations of the Thermal Fatigue Lifetime of CBGA Packages

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 1113-1134页

作者： Borui yang jun Luo Bo Wan Yutai Su Guicui fu Xu Long School of Reliability and Systems Engineering Beihang UniversityBeijing100191China Sichuan Institute of Solid-State Circuits China Electronics Technology Group CorporationChongqing400060China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China

A thermal fatigue lifetime prediction model of ceramic ball grid array(CBGA)packages is proposed based on the Darveaux model.A finite element model of the CBGA packages is established,and the Anand model is used to describe the viscoplasticity of the CBGA solder.The average viscoplastic strain energy density increment △Wave of the CBGA packages is obtained using a finite element simulation,and the influence of different structural parameters on theWave is analyzed.A simplified analytical model of the △Wave is established using the simulation data.The thermal fatigue lifetime of CBGA packages is obtained from a thermal cycling test.The Darveaux lifetime predictionmodel ismodified based on the thermal fatigue lifetime obtained fromthe experiment and the corresponding △Wave.A validation test is conducted to verify the accuracy of the thermal fatigue lifetime prediction model of the CBGA packages.This proposed model can be used in engineering to evaluate the lifetime of CBGA packages.

关键词： CBGA packages lifetime prediction finite element method thermal fatigue Anand model Darveaux model

Novel lanthanide coordination polymers based on mixed N,O-donor ligands and their visible-light-driven photocatalytic performance

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Journal of Rare Earths 2023年第1期41卷 85-90页

作者： jun Chen Weizhi Kou Shunsheng He Chenlan Lin Xin Wang Lianshe fu Ting-Hai yang Jiangsu Laboratory of Precious Metals Processing Technology and Application School of Chemistry&Environmental EngineeringJiangsu University of TechnologyChangzhou 213001China Department of Physics CICECO-Aveiro Institute of MaterialsUniversity of Aveiro3810-193AveiroPortugal

In the present work,we prepared three isostructural lanthanide(Ln) coordination polymers(CPs).namely [Ln(Hhpc)(phen)(NO_(3))](Ln=Gd(1),La(2),Y(3),H_(3)hpc=5-hydroxy-1 H-pyrazole-3-carboxyIic acid,phen=1,10-phenanthroline) by hydrothermal method.Their structures were characterized by single crystal X-ray diffraction,Fourier transform infrared spectrum,elemental analysis,powder X-ray diffraction and thermal gravimetric analysis.CPs 1-3 are isostrutural and exhibit two-dimensional(2 D)wavy layered structure constructed from inorganic chains,in which equivalent eight coordinated Ln^(3+) ions are linked through carboxylate groups.The three dimensional supramolecular structure is further formed by hydrogen bonding.The photocatalytic experiments show that CPs 2 and 3 exhibit good photocatalytic performances under visible light in degradation of methylene blue organic dye.The photocatalytic degradation efficiencies in 90 min are about 86.19% and 93.60% for CPs 2 and 3,respectively.The photocatalytic degradation mechanisms have been proposed through photoelectrochemical and trapping radical experiments.

关键词： Lanthanides Coordination polymers Photocatalytic degradation Pyrazole carboxylic acid Rare earths