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Saddle pulmonary embolism is not a sign of high-risk deterioration in non-high-risk patients: A propensity score-matched study

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World Journal of Emergency Medicine 2021年第4期12卷 261-267页

作者： dong Jia Chao Ji Min zhao Department of Emergency Medicine Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Clinical Epidemiology Shengjing Hospital of China Medical UniversityShenyang 110004China

BACKGROUND: There is controversy regarding whether saddle main pulmonary artery(MPA) embolism represents a high risk of deterioration in non-high-risk acute pulmonary embolism(PE) patients. This study aims to address this issue by conducting a propensity score matching(PSM) ***: A total of 727 non-high-risk acute PE patients were retrospectively evaluated. We evaluated the Bova score and risk stratification to examine the risk of deterioration. Deterioration defined as any adverse event within 30 days after admission. Computed tomographic pulmonary angiography was used to identify the embolism type. All patients were matched into four subgroups by PSM according to age, sex, Bova score, and risk stratification:(1) MPA and non-MPA embolism;(2) non-saddle MPA and non-MPA embolism;(3) saddle MPA and non-saddle MPA embolism;(4) saddle MPA and non-MPA embolism. Correlations were analyzed using Cox regression analysis, and deterioration risk was compared between subgroups using Kaplan-Meier ***: Cox regression analysis revealed that MPA embolism was correlated with deterioration, regardless of whether saddle MPA embolism was included or excluded. Saddle MPA embolism was not correlated with deterioration, regardless of comparison with non-saddle MPA embolism or non-MPA embolism. Patients with MPA and non-saddle MPA embolism presented a high risk for deterioration(logrank test=5.23 and 4.70, P=0.022 and 0.030, respetively), while patients with saddle MPA embolism were not at a high risk of deterioration(log-rank test=1.20 and 3.17, P=0.729 and 0.077, respetively).CONCLUSIONS: Saddle MPA embolism is not indicative of a high risk of deterioration in nonhigh-risk acute PE patients.

关键词： Main pulmonary artery Pulmonary embolism Computerized tomography pulmonary arteriography

A criterion on a repeller being a null set of any limit measure for stochastic differential equations

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Science China Mathematics 2021年第2期64卷 221-238页

作者： Lifeng Chen zhao dong Jifa Jiang Mathematics and Science College Shanghai Normal UniversityShanghai 200234China RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper studies limit behaviors of stationary measures for stochastic ordinary differential equations with nondegenerate noise and presents a criterion to guarantee that a repeller with zero Lebesgue measure is a null set of any limit *** this criterion,we first provide a series of nontrivial concrete examples to show that their repelling limit cycles or quasi-periodic orbits are null sets for all limit measures,which deduces that all their limit measures are concentrated on stable equilibria and stable limit cycles or quasi-periodic orbits,and *** open questions on exact supports of limit measures are proposed.

关键词： stationary measure limit measure support Lyapunov function repelling limit cycle repelling quasi-periodic orbit

ZP2:the precision regulator of egg coat architecture during fertilization

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Science China(Life Sciences) 2024年第8期67卷 1779-1780页

作者： Yi dong Shigang zhao Han zhao State Key Laboratory of Reproductive Medicine and Offspring Health Center for Reproductive MedicineInstitute of WomenChildren and Reproductive HealthShandong UniversityJinan 250012China

In a recent study published in Cell,(Nishio et al.,2024)elucidated the molecular regulatory mechanism through which organisms prevent *** process intricately involves conformational changes in the zona pellucida(ZP)*** authors present a fascinating mechanism whereby post-fertilization cleavage of the ZP subunit ZP2 triggers its oligomerization,leading to crosslinking of filaments to harden the egg coat and prevent *** also systematically analyzed the pattern of ZP filament assembly,which revealed that two protofilaments comprising type I(ZP3)and type II(ZP1/ZP2/ZP4)components interlock to form a left-handed double helix *** findings are immensely beneficial for understanding the specific role of the egg coat,providing a plethora of insights.

关键词： mechanism finding crosslinking

Littlewood–Paley Operators on Spaces with Variable Exponent on Homogeneous Groups

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Acta Mathematica Sinica,English Series 2020年第5期36卷 535-558页

作者： dong Li LIU Ji Man zhao Key Laboratory of Mathematics and Complex Systems Ministry of Education Institution of Mathematics and Mathematical Education School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,on homogeneous groups,we study the Littlewood–Paley operators in variable exponent ***,we prove that the weighted Littlewood–Paley operators are controlled by the weighted Hardy–Littlewood maximal function,and obtain the vector-valued inequalities of the Littlewood–Paley operators,including the Lusin function,Littlewood–Paley g function and gλ* ***,we prove the boundedness of multilinear Littlewood–Paley gψ,λ* function.

关键词： Littlewood–Paley operators variable Lebesgue spaces homogeneous groups

Unravelling the Structural Development of Peptide-Coordinated Iron-Sulfur Clusters:Prebiotic Evolution and Biosynthetic Strategies

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Chinese Journal of Chemistry 2022年第12期40卷 1478-1491页

作者： Yijun dong Siqi Zhang Liang zhao School of Life Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

Iron-sulfur(Fe-S)proteins are among the most common type of natural metalloproteins that participate in a large range of key metabolic *** date,enormous research works on the exploration of protein structures and catalytic mechanisms have revealed that the active sites are generally composed of a Fe-S cluster and a highly conserved coordination ***,people are enlightened by the prebiotic evolution of an-cient clusters and are dedicated to the development of biosynthetic methods for modern *** review aims to systemically summarize the structural development of peptide-coordinated iron-sulfur clusters from two perspectives:"bottom-up"approaches involving evolution of prebiotic chemical synthesis for natural proteins and"top-down"analyses of biosynthesis in modern biological systems for artificial ***,current challenges and the direction of future development are also presented to provide new perspectives of developing enzyme mimics and further mechanistic studies.

关键词： Peptides Iron-sulfur clusters Prebiotic evolution Biosynthesis Biomimetic synthesis

Wire-like nano-polyaniline deposited electrochemically in a reverse micelle electrolyte as a p H sensor

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1115-1119页

作者： Fei zhao Han-dong Jiao Shi-qiang zhao State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Wire-like polyaniline(PANI) films were successfully electrodeposited onto an indium tin oxide(ITO) substrate using a pulse galvanostatic method(PGM) in a reverse micelle electrolyte. The as-prepared PANI films were electrochemically analyzed by cyclic voltammetry and electrochemical impedance spectroscopy in 1 mol·L-1 HCl O4 solution. It is found that the as-prepared PANI films are highly porous, exhibit the diameters of approximately 100 nm and the lengths exceeding 3 μm, and have favorable electrochemical activities. Furthermore, the as-prepared wire-like PANI films show a good linear relationship of the potentiometric response curve over the p H value range of 3–10 with a slope of 74.13 m V·p H-1 in 0.5 mol·L-1 K2HPO4 basal solutions. The results demonstrate that the prepared wire-like PANI films are promising p H sensors.

关键词： electrodeposition polymers sensors thin films

Microstructure and Abrasive Wear Behavior of Medium Carbon Low Alloy Martensitic Abrasion Resistant Steel

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Journal of Iron and Steel Research International 2014年第1期21卷 98-103页

作者： Xiang-tao DENG zhao-dong WANG Yi HAN Hui zhao Guo-dong WANG State Key Laboratory of Rolling and Automation Northeastern University Yangxi Harbor Electric Power Development Co. Ltd.

The effect of processing parameters such as hot rolling and heat treatment on microstructure and mechanical properties was investigated for a new 0.27mass% C and Ni, Mo-free low alloy martensitic abrasion resistant steel. The three-body impact abrasive wear behavior was also analyzed. The results showed that two-step controlled rolling besides quenching at 880 ℃ and tempering at 170 ℃ could result in optimal mechanical property., the Brinell hardness, tensile strength, elongation and --40 ℃ impact toughness were 531, 1530 MPa, 11.8% and 58 J, re- spectively. The microstructure was of fine lath martensite with little retained austenite. Three-body impact abrasive wear results showed that wear mechanism was mainly of plastic deformation fatigue when the impact energy was 2 J, and the relative wear resistance was 1.04 times higher than that of the same grade compared steel under the same working condition. The optimal hardness and toughness match was the main reason of higher wear resistance.

关键词： abrasion resistant steel processing parameter mechanical property relative wear resistance

An analytic model for transient heat conduction in bi-layered structures with flexible serpentine heaters

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1279-1296页

作者： zhao zhao Yuhang LI Sujun dong Yi CUI Zheng DAI Institute of Solid Mechanics Beihang UniversityBeijing 100191China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Shanghai Aircraft Design&Research Institute of Commercial Aircraft Corporation of China(COMAC) Shanghai 201210China

Uniform heating of complex surfaces,especially non-developable surfaces,is a crucial problem that traditional rigid heaters cannot *** by flexible electronic devices,a novel design for the stretchable heating film is proposed with the flexible serpentine wire embedded in the soft polymer film,which can be attached to non-developable surfaces *** provides a new way for the stretchable heaters to realize uniform heating of complex ***,the thermal field of flexible serpentine heaters(FSHs)depends on the configurations of the embedded serpentine heating wire,which requires accurate theoretical prediction of real-time temperature ***,the analytical model for the transient heat conduction in FSHs is solved by the separation of variables method and validated by the finite element analysis(FEA)in this *** on this model,the effects of the geometric parameters,such as the radius and the length of the serpentine heaters,on the thermal uniformity are systematically *** study can help to design and fabricate flexible heaters with uniform heating in the future.

关键词： serpentine heater bi-layered structure transient heat conduction temperature distribution

Experimental and Theoretical Studies of C_(3)F_(7)CN/CO_(2) Mixture Decomposition Under Overheating Fault

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CSEE Journal of Power and Energy Systems 2022年第3期8卷 941-951页

作者： Mingyue zhao dong Han Weikang zhao Zhenrui Zhou Guoqiang Zhang Institute of Electrical Engineering Chinese Academy of Sciencesand University of Chinese Academy of SciencesBeijing 100190China

Heptafluoroisobutyrontrile(C_(3)F_(7)CN)performs well in dielectric properties and environmental protection,which has the potential to replace SF6 *** decomposition characteristics of C_(3)F_(7)CN mixture under fault conditions directly affect the possibility of its replacement for SF6 ***,the number of studies on the decomposition characteristics of C_(3)F_(7)CN mixture under overheating fault is *** this paper,the decomposition characteristics of C_(3)F_(7)CN/CO_(2) mixture under an overheating fault are studied by gas chromatography-mass spectrometry(GC/MS)and quantum chemical *** CO,C_(3)F_(6) and HF are detected at 200℃.At 550℃,the C_(3)F_(7)CN molecule begins to decompose and produces CHF_(3),C_(2)F_(4),CF_(3)CN and ***,the results of GC/MS show that the insulation medium C_(3)F_(7)CN contains an impurity,which is C3HF7(HFC-227ea).Combined with the results of GC/MS and quantum chemistry calculations,it can be concluded that the decomposition by-product C_(3)F_(6) at 200℃ mainly comes from the decomposition of C_(3)HF_(7).C_(3)HF_(7) reduces the decomposition temperature of the C_(3)F_(7)CN/CO_(2) ***,it is very important to improve the purity of the insulation medium C_(3)F_(7)CN.

关键词： C3F7CN decomposition mechanism environmentally-friendly gas-insulating medium GC/MS quantum chemical