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Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(Gws) within the standard model of particle physics. If these background Gws could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

SUPERPLASTICITY AND DIFFUSION bONDING OF IN718 SUPERALLOY

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 307-312页

作者： w.b. Han K.F. Zhang b. wang D.Z. wu School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The superplasticity and diffusion bonding of IN718 superalloy were studied in this article. The strain rate sensitivity index m was obtained at different temperatures and various initial strain rates using the tensile speed mutation method; m reached its maximum value 0.53 at an initial strain rate of 1×10^-4s^-1 at 1253K. The diffusion bonding parameters, including the bonding temperature T, pressure p, and time t, affected the mechanism of joints. when the bonded specimen with 25μm thick nickel foil interlayer was tensile at room temperature, the shear fracture of the joints with nickel foil interlayer took place at the IN718 part. Microstructure study was carried out with the bonded samples. The microstructure shows an excellent bonding at the interfaces. The optimum parameters for the diffusion bonding are： T = 1273-1323K, p = 20-30MPa, t = 45-60min.

关键词： superplasticity diffusion bonding nickel foil IN718 alloy

STUDY ON bIOLEACHING OF PRIMARY CHALCOPYRITE ORE wITH THERMOACIDOPHLIC ARCHAE

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 341-346页

作者： P. Zou w.b. Zhang T. Lei J.K. wang Kunming University of Science and Technology Kunming 650093 China Technology Center Yunnan Metallurgy Group Co. Ltd. Kunming 650031China

A high temperature-tolerating thermoacidophilic archae （TA） was isolated from water samples collected from a hot sulfur-containing spring in the Yunnan Province, China, and was used in bioleaching experiments of a low-grade chalcopyrite ore. The TA grow at temperatures ranging from 40 to 80℃, with 65℃ being the optimum temperature, and at pH values of l.5 to 4.0, with an optimum pH value of 2.0. The bioleaching experiments of the chalcvpyrite ore were conducted in both laboratory batch bioreactors and leaching columns. The results obtained from the bioreactor experiments showed that the TA bioleaching rate of copper reached 97% for a 12-day leaching period, while the bioleaching rate was 32.43% for thiobacillus ferrooxidans （Tf） leaching for the same leaching time. In the case of column leaching, tests of a two-phase leaching （196 days）, that is, a two-month （56 days） Tf leaching in the first phase, followed by a 140-day TA leaching in the second phase were performed. The average leaching rate of copper achieved for the 140-day TA leaching was 195mg/（L.d）, while for the control experiments, it was as low as 78mg/（L .d） for the Tf leaching, indicating that the TA possesses a more powerful oxidizing ability to the chalcopyrite than Tf Therefore, it is suggested that the two-phase leaching process be applied to .for the heap leaching operations, whereas, the TA can be used in the second phase when the temperature inside the heap has increased, and the primary copper sulfide minerals have already been partially oxidized with Tf beforehand in the first phase.

关键词： chalcopyrite biological oxidation thermoacidophilic archae mesophile batch stirred bioleaching column bioleaching

CRYSTALLOGRAPHIC HOMOGENIZATION FINITE ELEMENT METHOD AND ITS APPLICATION ON SIMULATION OF EVOLUTION OF PLASTIC DEFORMATION INDUCED TEXTURE

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Acta Mechanica Solida Sinica 2010年第1期23卷 36-48页

作者： Yiping Chen w.b. Lee E. Nakamachi Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory for Forming Simulation and Die and Mould Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China Department of Mechanical Engineering Osaka Institute of Technology Osaka Japan

A crystallographic homogenization method is proposed and implemented to predict the evolution of plastic deformation induced texture and plastic anisotropy （earring） in the stamping of polycrystalline sheet metals. The microscopic inhomogeneity of crystal aggregate has been taken into account with the microstructure made up of a representative aggregate of single crystal grains. Multi-scale analysis is performed by coupling the microscopic crystal plasticity with the macroscopic continuum response through the present homogenization procedure. The macroscopic stress is defined as the volume average of the corresponding microscopic crystal aggregations, which simultaneously satisfies the equation of motion in both micro- and macro-states. The proposed numerical implementation is based on a finite element discretization of the macrocontinuum, which is locally coupled at each Gaussian point with a finite element discretization of the attached micro-structure. The solution strategy for the macro-continuum and the pointwiseattached micro-structure is implemented by the simultaneous employment of dynamic explicit FE formulation. The rate-dependent crystal plasticity model is used for the constitutive description of the constituent single crystal grains. It has been confirmed that Taylor＇s constant strain homogenization assumption yields an undue concentration of the preferred crystal orientation compared with the present homogenization in the prediction of texture evolution, with the latter having relaxed the constraints on the crystal grains. Two kinds of numerical examples are presented to demonstrate the capability of the developed code： 1） The texture evolution of three representative deformation modes, and 2） Plastic anisotropy （earring） prediction in the hemispherical cup deep drawing process of aluminum alloy A5052 with initial texture. by comparison of simulation results with those obtained employing direct crystal plasticity calculation adopting Taylor assumption,

关键词： homogenization crystal plasticity texture microstructure earring

RGS4 promotes the progression of gastric cancer through the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase b pathway and epithelial-mesenchymal transition

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world Journal of Gastroenterology 2025年第2期31卷 113-127页

作者： Peng-Yu Chen Pei-Yao wang bang Liu Yang-Pu Jia Zhao-Xiong Zhang Xin Liu Dao-Han wang Yong-Jia Yan wei-Hua Fu Feng Zhu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Department of General Surgery Jincheng People’s HospitalJincheng 048000Shanxi ProvinceChina

bACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G *** speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet *** To explore the role and underlying mechanisms of action of RGS4 in GC *** The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with *** assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in *** RGS4 was highly expressed in GC tissues compared with matched adjacent normal *** RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with *** experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and ***,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor ***,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase b,decreased vimentin and N-cadherin,and elevated *** High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic ***4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase b pathway and epithelial-mesenchymal transition.

关键词： Gastric cancer Prognosis Regulator of G protein signaling 4 Focal adhesion kinase Epithelial-mesenchymal transition

PRELIMINARY STUDY ON MAKING OF wATER RESISTANCE wOOD FIbERbOARD

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Journal of Northeast Forestry University 1991年第2期2卷 54-60页

作者： banks w.b. Jones G.L. North wales University North Wales University United KingdomUnited Kingdom

In the present study,described that preparation of oligoesterified wood fibre by theaddition reaction of the wood fibre with maleic anhydride(MA)and allyl glycidyl ether(AGE).Further,made of crosslinkable oligoesterified fiber board at high temperature and underhigh pressues,accompanying plasticization of the wood fibre *** product exhibitedthe high the modulus of repture in bending(MOR),good water repellency and dimesionalstability.

关键词： wood fibre Oligoestcriflcation Fiberboard

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

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Neural Regeneration Research 2025年第11期20卷 3245-3258页

作者： Jiayi wang Mengke Zhao Dong Fu Meina wang Chao Han Zhongyue Lv Liang wang Jing Liu Stem Cell Clinical Research Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina Institute(College)of Integrative Medicine Dalian Medical UniversityDalianLiaoning ProvinceChina

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived *** lays a foundation for the development of potentially potent new treatment modalities for ischemic ***,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical *** promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic *** found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal *** human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase b,and these effects were reversed by treatment with a phosphoinositide 3-kinase *** findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase b/mammalian target of rapamycin signaling ***,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety ***,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

关键词： behavior exosome extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase b(AKT)

Copper homeostasis and neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3124-3143页

作者： Yuanyuan wang Daidi Li Kaifei Xu Guoqing wang Feng Zhang International Research Laboratory of Ethnomedicine of Ministry of Education Key Laboratory of Basic Pharmacology of Ministry of EducationLaboratory Animal Center and Key Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyiGuizhou ProvinceChina

Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of *** homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7b),and the three copper chaperones ATOX1,CCS,and *** in copper homeostasis can lead to either the deficiency or accumulation of copper in brain *** evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative ***,the exact mechanisms underlying these processes are not *** is a potent oxidant that increases reactive oxygen species production and promotes oxidative *** reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial *** oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory ***,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell *** study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease *** synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of heredit

关键词： Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease wilson's disease

Structure modification and recovery of amorphous Fe_(73.5)Si_(13.5)b_9Nb_3Cu_1 magnetic ribbons after autoclave treatment:SAXS and thermodynamic analysis

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Journal of Materials Science & Technology 2019年第1期35卷 118-126页

作者： L.Y.Guo X.wang K.C.Shen K.b.Kim S.Lan X.L.wang w.M.wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education Shandong University Department of Nanotechnology and Advanced Materials Engineering Sejong University Herbert Gleiter Institute of Nanoscience School of Materials Science and Engineering Nanjing University of Science and Technology Department of Physics City University of Hong Kong

The structure, crystallization kinetics and magnetic property of as-quenched Fe_(73.5)Si_(13.5)b_9Nb_3Cu_1 amorphous ribbon(R0) as well as ribbons after autoclave treatment at 100°C and 150°C(R1 and R2) have been systematically studied by various techniques. with increasing autoclave treatment temperature,the measured structural, kinetic and magnetic parameters of samples increase firstly, i.e. R0 by transforming from fcc to bcc structure during the autoclave treatment and that the autoclave treatment can decrease the large radius(r_M) MRO(medium range order),but increase the small rMMRO. The measured structural, thermal and magnetic parameters of R2 sample have a tendency to recover toward as-quenched R0 sample. The thermal and magnetic parameters of samples after solely annealing treatment at higher temperature have no obvious recover *** uneven actions of pressure and temperature in autoclave treatment may be helpful for us to search a new method to improve the magnetic properties of Fe-based glasses.

关键词： SAXS (small-angle X-ray scattering) Fe-based glass Thermodynamic Magnetic ribbon DSC (differential scanning calorimetry)