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Effect of tankyrase 1 on autophagy in the corpus cavernosum smooth muscle cells from ageing rats with erectile dysfunction and its potential mechanism

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Asian Journal of Andrology 2010年第5期12卷 744-752页

作者： Jian Zhang Xiao-Jun Wu de-xiang zhuo Tao Liu Wei-Ren Li Ze-Bin Mao Zhong-Cheng Xin Andrology Center First Hospital Peking University Beijing 100009 China Institute of Urinary Surgery Southwest Hospital Third Military Medical University Chongqing 400038 China The department of Biochemistry and Molecular Biology Health Science Center Peking University Beijing 100191 China

This study compared tankyrase 1 expression and autophagy quantity between erectile dysfunction （ED） and non-ED rats＇ corpus cavernosum smooth muscle cells （CSMCs）. This study aslo explored the effect and possible mechanism of tankyrase 1 on autophagy and cell proliferation in ageing ED rats＇ CSMCs. The intracavernous pres- sure and mean systemic arterial pressure were measured to investigate erectile function so that eight 24-month-old ED and eight 8-month-old male Wistar rats were choosed respectively. The rat CSMCs were isolated and cultured by enzyme digestion, in which tankyrase 1 expression and autophagy quantity were compared. Tankyrase 1 over-expression was induced with plasmid transfection by Lipofectamine^TM. The effect of tankyrase 1 overexpression on proliferation, autophagy and mTOR pathway in 24-month-old ED rats＇ CSMCs was measured by the cell growth curve in MTT assay, cell cycle analysis in flow cytometry （FCM）, key protein expression in Western blot, autophagy quantity in transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 fluorescence. The primary CSMCs were confirmed by immunofluorescence, and the purity was 99.1% in FCM. Compared with that of 8-month-old rats, tankyrase 1 expression and autophagy quantity significantly decreased in 24-month-old ED rats＇ primary CSMCs （P 〈 0.01）. Tankyrase 1 overexpression significantly increased the growth rate （P 〈 0.05） and increased the S phase of cell cycle （P 〈 0.01）. The autophagosome quantity was remarkably increased （P 〈 0.01）, LC3-Ⅰ/Ⅱ and Beclin 1 were upregulated （P 〈 0.01 and P 〈 0.05）, and p-p70S6K （Thr389） was downregulated in 24-month-old ED rat CSMCs （P 〈 0.05）. In conclusion, Tankyrase 1 and autophagy decrease in the CSMCs from aging rats with ED, and tankyrase 1 may have a positive effect on proliferation by enhancing autophagy and regulating the mTOR signalling pathway.

关键词： ageing autophagy corpora cavernosum corpus cavemosum smooth muscle cells erectile dysfunction senile tankyrase

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Optimizing hemicelluloses pre-extraction in eucalyptus kraft pulping:A pathway towards enhancing pulp mill biorefineries

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Chinese Journal of Chemical Engineering 2024年第6期70卷 162-172页

作者： Yuhan Wang Danqi Xue Jingjing zhuo Zhouyang xiang State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

A critical pathway towards enhancing pulp mill biorefineries is to integrate the extraction and utilization of hemicelluloses into the pulping ***,an industrial pre-extraction strategy for hemicelluloses targeting eucalyptus kraft pulping process was *** solution or pulping white liquor was used to pre-extract hemicelluloses before the actual pulping *** response surface methodology(RSM)technique was applied to investigate the most suitable conditions to maximize the yield of these hemicelluloses while simultaneously minimizing the damage to pulp yields and ***(105 to 155℃),alkali concentration(3%to 8%),sulfidity(20%to 30%)and retention time(19 to 221 min)were combined to evaluate their effects on hemicellulose yields and chemical *** optimal pre-extraction conditions identified in this work(5.75%NaOH concentration,25%sulfidity at 135℃for 60 min)successfully allowed recovering 4.8%of hemicelluloses(based on the wood dry mass)and limited damages to pulp yields and *** cellulose content in pulp can even be increased by about 10%.Hemicellulose emulsification properties were also evaluated,which were comparable to synthetic *** study provides an industrial pathway to effectively separate and utilize wood hemicelluloses from the pulping process,which has the potential to improve the economy and material utilization of pulp and paper mills.

关键词： Hemicelluloses Xylan Pre-extraction Kraft pulping Emulsifying Response surface methodology(RSM)

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Atiyah Classes of Strongly Homotopy Lie Pairs

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Algebra Colloquium 2019年第2期26卷 195-230页

作者： zhuo Chen Honglei Lang Maosong xiang department of Mathematics Tsinghua University Beijing 100084 China department of Applied Mathematics China Agricultural University Beijing 100083f China Beijing International Center for Mathematical Research Peking University Beijing 100871 China

The subject of this paper is strongly homotopy (SH) Lie algebras, also known as L∞-algebras. We extract an intrinsic character, the Atiyah class, which measures the nontriviality of an SH Lie algebra A when it is extended to L. In fact, with such an SH Lie pair (L, A) and any A-module E, there is associated a canonical cohomology class, the Atiyah class [α^E], which generalizes the earlier known Atiyah classes out of Lie algebra pairs. We show that the Atiyah class [α^L/A] induces a graded Lie algebra structure on HCE·(A,L/A[-2]), and the Atiyah class [α^E] of any A-module E induces a Lie algebra module structure on HCE(A,E). Moreover, Atiyah classes are invariant under gauge equivalent A-compatible infinitesimal deformations of L.

关键词： homotopical algebra L∞-algebra Atiyah class

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Back Pressure Characteristics for Turbine Channel of External-Parallel TBCC Inlet

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第5期36卷 808-816页

作者： SUN Bo xiang Cuiling zhuo Changfei department of Aerospace Engineering Nanjing University of Science and TechnologyNanjing 210094P.R.China Shanxi North Xing'an Chemical Indutry Co. Ltd.Taiyuan 030008P.R.China.

For investigating the back pressure characteristics of turbine channel of an external-parallel turbine-based combined cycle(TBCC)inlet during the mode transition with the freestream air Mach number of 1.8,wind tunnel tests and numerical simulations are carried *** results show that the critical back pressure of the turbine channel decreases linearly with the decrease of the open degree of splitter *** turbine channel has self-starting capacity when the open degree of the turbine channel is 100%.The total pressure recovery coefficient increases with the increase of back pressure when turbine channel is at supercritical and critical *** mass capture ratio,total pressure recovery coefficient and outlet pressure ratio decrease obviously when turbine channel is at subcritical *** of the research would provide scheme reference and technology storage for TBCC propulsion evolution.

关键词： turbine-based combined cycle inlet turbine channel mode transition back pressure wind tunnel test

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Thermal fatigue and wear of compacted graphite iron brake discs with various thermomechanical properties

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China Foundry 2024年第3期21卷 248-256页

作者： Gui-quan Wang zhuo Xu Zhong-li Liu xiang Chen Yan-xiang Li School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake *** this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical *** graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of *** peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction *** morphology of thermal cracks and 3D profiles of the worn surfaces were also *** is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue *** of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal *** the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.

关键词： compacted graphite iron brake disc thermomechanical properties thermal fatigue wear

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A Study on White Dwarf Masses in Cataclysmic Variables Based on XMM-Newton and Suzaku Observations

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Research in Astronomy and Astrophysics 2022年第4期22卷 21-35页

作者： zhuo-Li Yu Xiao-Jie Xu xiang-Dong Li School of Astronomy and Space Science and Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing210093China

The distribution of the mass of white dwarfs(WDs)is one of the fundamental questions in the field of cataclysmic variables(CVs).In this work,we make a systematical investigation on the WD masses in two subclass of CVs:intermediate polars(IPs)and non-magnetic CVs in the solar vicinity based on the fiux ratios of Fe XXVI-Lyαto Fe XXV-Heαemission lines(I_(7.0)/I_(6.7))from archival XMM-Newton and Suzaku *** first verify the(semi-empirical)relations between I_(7.0)/I_(6.7),the maximum emission temperature(T_(max))and the WD mass(M_(WD))with the mkcfiow model based on the apec description and the latest Atom *** then introduce a new spectral model to measure M_(WD)directly based on the above relations.A comparison shows that the derived M_(WD)is consistent with dynamically measured ***,we obtain the average WD masses of 58 CVs(including 36IPs and 22 non-magnetic CVs),which is the largest X-ray selected *** average WD masses are=0.81±0.21 M☉and=0.81±0.21M☉ for IPs and non-magnetic CVs,*** results are consistent with previous works.

关键词： (stars:)binaries(including multiple):close (stars:)novae cataclysmic variables X-rays:binaries

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Synthesis of novel chiral phosphine-triazine ligand derived fromα-phenylethylamine for Pd-catalyzed asymmetric allylic alkylation

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Chinese Chemical Letters 2008年第3期19卷 261-263页

作者： Jia Di Huang xiang Ping Hu zhuo Zheng Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 PR China Graduate School of Chinese Academy of Sciences Beijing 100039 PR China

A novel chiral phosphine-triazine ligand was synthesized from chiral α-phenylethylamine through a three-step procedure. In a model reaction of Pd-catalyzed allylic alkylation of rac-1,3-diphenylprop-2-en-1-y1 pivalat... 详细信息

关键词： Synthesis α-Phenylethylamine Phosphine-triazine ligand Pd-catalyzed allylic alkylation

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The dominant driving force for supercontinent breakup: Plume push or subduction retreat?

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Geoscience Frontiers 2018年第4期9卷 997-1007页

作者： Nan Zhang zhuo Dang Chuan Huang Zheng-xiang Li Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Earth Dynamics Research Group ARC Center of Excellence for Core to Crust Fluid Systems(CCFS)and The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin University

Understanding the dominant force responsible for supercontinent breakup is crucial for establishing Earth＇s geodynamic evolution that includes supercontinent cycles and plate tectonics. Conventionally,two forces have been considered： the push by mantle plumes from the sub-continental mantle which is called the active force for breakup, and the dragging force from oceanic subduction retreat which is called the passive force for breakup. However, the relative importance of these two forces is unclear. Here we model the supercontinent breakup coupled with global mantle convection in order to address this question. Our global model features a spherical harmonic degree-2 structure, which includes a major subduction girdle and two large upwelling（superplume） systems. Based on this global mantle structure,we examine the distribution of extensional stress applied to the supercontinent by both subsupercontinent mantle upwellings and subduction retreat at the supercontinent peripheral. Our results show that：（1） at the center half of the supercontinent, plume push stress is ～3 times larger than the stress induced by subduction retreat;（2） an average hot anomaly of no higher than 50 K beneath the supercontinent can produce a push force strong enough to cause the initialization of supercontinent breakup;（3） the extensional stress induced by subduction retreat concentrates on a ～600 km wide zone on the boundary of the supercontinent, but has far less impact to the interior of the supercontinent. We therefore conclude that although circum-supercontinent subduction retreat assists supercontinent breakup, sub-supercontinent mantle upwelling is the essential force.

关键词： Supercontinent breakup Plume push Subduction retreat

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Microstructure and formation mechanism of SHS joining between C_f/Al composites and TiAl intermetallic with Al–Ni–CuO interlayer

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Rare Metals 2015年第1期34卷 17-21页

作者： zhuo-Ran Li Guang-Jie Feng Kai Xu xiang-Long Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

In this study, it was reported a novel approach for joining Cf/A1 composites and TiA1 intermetallic by self- propagating high-temperature synthesis （SHS）. Mixed powders of 14A1-2Ni-3CuO were used as the SHS inter- layer, and differential thermal analysis test of A1-Ni-CuO interlayer was conducted to analyze the exothermic char- acteristic. Sound joint was got by SHS joining under the conditions of 600 ℃, 30 min, and 5 MPa. The joint was characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and X-ray diffrac- tion （XRD）. TiA13 and NiA13 are, respectively, formed in the TiA1/interlayer and Cf/A1/interlayer interfaces. Reac- tion products of Ni2Al3, NiAl3, A1203, and Cu were observed in the interlayer. And the formation mechanism of SHS joining was investigated.

关键词： SHS Joining Microstructure Formationmechanism A1-Ni-CuO interlayer

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Evolution of the Lagrangian drift and vortex added-mass of a growing vortex ring

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Journal of Hydrodynamics 2021年第4期33卷 725-735页

作者： Shu-jia Lin Yang xiang zhuo-qi Li Fu-xin Wang Hong Liu School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

The vortex-based propulsive systems’ enhanced performance greatly contributes to the vortex added-mass effect, which was initially developed to explain the added drag when a solid body accelerates in fluids. However, the solution of the instantaneous vortex added-mass coefficient is still remaining a question because vortices always do not have a stable geometric shape like solid bodies. In this paper, the formation of a canonical vortex ring is performed to investigate the nature of vortex added-mass and explore a solution for estimating the vortex added-mass coefficient. The vortex ring is generated by a piston-cylinder apparatus, and the time-dependent flow fields are recorded by particle image velocimetry technique. The ridges of finite-time Lyapunov exponent are applied to identify the Lagrangian boundary of the vortex ring. It is found that a part of the ambient fluids is entrained by the vortex ring when it propagates downstream, resulting in the growth of the vortex ring. Besides, a significant drift of the ambient fluid is observed to bypass the Lagrangian boundary of the vortex ring and reveals the nature of the vortex added-mass. Thus, the added-mass coefficient of the vortex is redefined as the ratio of the volume of the Lagrangian drift fluids in finite time interval step to the vortex volume at that instant. By referring to McPhaden’s method to estimate the added-mass of a solid body, a method based on the multiple material lines with relative-timestep is developed to estimate the volume of Lagrangian drift fluids induced by the vortex added-mass. Then, an empirical criterion for determining the material line number and the finite time interval step is suggested for the vortex ring flow, and the eventual vortex added-mass coefficient calculated by the volume of Lagrangian drift fluids is found to well agree with the results of Brennen. Moreover, the method based on multiple material lines for calculating Lagrangian drift fluids’ volume suggests a poten

关键词： Added-mass Lagrangian coherent structure(LCS) finite-time Lyapunov exponent(FTLE)

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