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Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida Sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang Shi-Wen Chen Si-he Wang zhen-Yuan gong Jun Feng Gang-Feng Wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng Liu zhen-xing Xing gong-jin Cheng Xue-yong Ding Xiang-xin Xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy

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Journal of Central South University 2024年第7期31卷 2181-2193页

作者： ZHANG Tao QIN zhen-yang gong Hai WU Yun-xin CheN Xin Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Welding and Additive Manufacturing Centre Cranfield UniversityBedfordMK430ALUK

Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu ***,inferior mechanical properties of WAAM deposited material restrict its industrial ***-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this *** effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 *** ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited *** cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the *** cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 *** strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening.

关键词： wire-arc additive manufacture inter-layer cold rolling thermal-mechanical treatment microstructure mechanical properties strengthening mechanism

The combined detection of carcinoembryonic antigen,carcinogenic antigen 125,and carcinogenic antigen 19-9 in colorectal cancer patients

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2073-2079页

作者： Ling-zhen gong Qian-Wen Wang Jie-Wen Zhu Department of Clinical Laboratory Huangshi Central Hospital(Affiliated Hospital of Hubei Polytechnic University)Hubei Key Laboratory of Kidney Disease Pathogenesis and InterventionHuangshi Tumor Molecular Diagnosis and Treatment Key LaboratoryHuangshi 435000Hubei ProvinceChina

BACKGROUND hepatic metastases are common and difficult to treat after colorectal cancer(CRC)*** predictive value of carcinoembryonic antigen(CEA),cancer antigen(CA)125 and CA19-9 combined tests for liver metastasis is *** To evaluate predictive value of combined tests for CEA,CA125,and CA19-9 levels in patients with liver metastases of *** The retrospective study included patients with CRC alone(50 cases)and patients with CRC combined with liver metastases(50 cases)who were hospitalized between January 2021 and January *** CEA,CA125 and CA19-9 levels were compared between the two groups,and binary logistic regression was used to analyze the predictive value of the combination of these tumor markers in liver *** addition,we performed receiver operating characteristic(ROC)curve analysis to assess its diagnostic *** The results showed that the serum CEA,CA125 and CA19-9 levels in the CRC with liver metastasis group were significantly higher than those in the CRC alone ***,the average serum CEA level in the CRC with liver metastasis group was 162.03±810.01 ng/mL,while that in the CRC alone group was 5.71±9.76 ng/mL;the average serum CA125 levels were 43.47±83.52 U/mL *** 13.5±19.68 U/mL;the average serum CA19-9 levels were 184.46±473.13 U/mL and 26.55±43.96 U/mL *** addition,binary logistic regression analysis showed that CA125 was significant in predicting CRC liver metastasis(Phe areas under the ROC curves of CEA,CA125 and CA19-9 were 0.607,0.692 and *** These results suggest that combined detection of these tumor markers may help early detection and intervention of CRC liver metastasis,thereby improving patient prognosis.

关键词： Colorectal cancer Liver metastasis Serum markers Carcinoembryonic antigen Cancer antigen 125 Cancer antigen 19-9 Receiver operating characteristic analysis

Phosphorylation of ZmAL14 by ZmSnRK2.2 regulates drought resistance through derepressing ZmROP8 expression

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Journal of Integrative Plant Biology 2024年第7期66卷 1334-1350页

作者： Yalin Wang Jinkui Cheng Yazhen Guo zhen Li Shuhua Yang Yu Wang Zhizhong gong State Key Laboratory of Plant Environmental Resilience Frontiers Science Center for Molecular Design BreedingCollege of Biological SciencesChina Agricultural UniversityBeijing 100193China Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijing 100193China College of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China

Drought stress has negative effects on crop growth and *** of transcription factors that regulate the expression of drought-responsive genes is critical for understanding the transcriptional regulatory networks in response to drought,which facilitates the improvement of crop drought ***,we identified an Alfin-like(AL)family gene ZmAL14 that negatively regulates drought *** of ZmAL14 exhibits susceptibility to drought while mutation of ZmAL14 enhances drought *** abscisic acid(ABA)-activated protein kinase ZmSnRK2.2 interacts and phosphorylates ZmAL14 at T38 *** of ZmSnRK2.2 gene decreases drought resistance of maize.A dehydration-induced Rho-like small guanosine triphosphatase gene ZmROP8 is directly targeted and repressed by *** of ZmAL14 by ZmSnRK2.2 prevents its binding to the ZmROP8 promoter,thereby releasing the repression of ZmROP8 *** of ZmROP8 stimulates peroxidase activity and reduces hydrogen peroxide accumulation after drought ***,our study indicates that ZmAL14 is a negative regulator of drought resistance,which can be phosphorylated by ZmSnRK2.2 through the ABA signaling pathway,thus preventing its suppression on ZmROP8 transcription during drought stress response.

关键词： ZmAL14 drought tolerance transcription factor maize

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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing he zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

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In Situ Raman Monitoring of Trace Antibiotics in Different Harsh Water Environments

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Energy & Environmental Materials 2024年第1期7卷 288-297页

作者： Chundong Liu Fengcai Lei Maogang gong Xiaoming Zhou Xiaofei Zhao zhen Li Chao Zhang Baoyuan Man Jing Yu School of Physics and Electronics Institute of Materials and Clean EnergyShandong Normal University College of Chemistry Chemical Engineering and Materials Science Institute of Biomedical Sciences Shandong Normal University Department of Physics and Astronomy University of Kansas Shandong Provincial Hospital Shandong First Medical University

in situ surface-enhanced Raman scattering(SERS) is a widely used operando analytical technique,while facing numerous complex factors in applications under aqueous environment,such as low detection sensitivity,poor ant... 详细信息

关键词： antibiotic detection hydrophobic structure In situ Raman metronidazole wettability

Nonexistence of quantum black and white hole horizons in an improved dynamic approach

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 56-73页

作者： Wen-Cong Gan Xiao-Mei Kuang zhen-Hao Yang Yungui gong Anzhong Wang Bin Wang College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou 310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou 310023China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we study the quantum geometric effects near the locations where classical black hole horizons used to appear in Einstein's classical theory,within the framework of an improved dynamic approach,in which the internal region of a black hole is modeled by the Kantowski-Sachs(KS)spacetime and the two polymerization parameters are functions of the phase space *** detailed analysis shows that the effects are so strong that black and white hole horizons of the effective quantum theory do not exist at all and instead are replaced by transition surfaces,across which the metric coefficients and their inverses are smooth and remain finite,as are the corresponding curvatures,including the Kretschmann *** surfaces always separate trapped regions from anti-trapped *** number of such surfaces is infinite,so the corresponding KS spacetimes become geodesically complete,and no black and white hole-like structures exist in this scheme.

关键词： canonical quantization loop quantum gravity quantum aspects of black holes

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Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway

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Asian Journal of Andrology 2024年第1期26卷 57-66页

作者： Chang-Bo Zhao Wei-Bo Chen Wen-zhen Wang Fang-Xin gong Cui-Qin Fan Ye Li Tian Lan Wen-Jing Wang Ming-zhen Yuan Department of Urology Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Andrology Liaocheng People's HospitalShandong UniversityLiaocheng 252000China Department of Urology The Second Hospital of Shandong UniversityJinan 250012China Department of Physiology School of Basic Medical SciencesShandong UniversityJinan 250012China

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction(DMED)a challenging *** factors contributing to DMED include oxidative stress,nitric oxide(NO)/cyclic guanosine monophosphate(cGMP)pathway activation,and apoptosis,while nitro-oleic acid(NO,-OA)has been shown to be beneficial in treating these aspects of this ***,herein,investigated the effects and possible mechanisms of NO,-OA on erectile function as assessed in a streptozotocin-induced rat model of *** results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control ***,in response to 4 weeks of NO,-OA treatment,there was an improvement in erectile *** expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED *** expression of proapoptotic factors was increased,while that of antiapoptotic factors was decreased in the DMED ***,the cell morphology in the cavernous tissue of the DMED group also changed ***,-OA treatment significantly reversed all these changes observed in the DMED *** conclusion,NO,-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress,activation of the NO/cGMP pathway,and a reduction in apoptosis.

关键词： apoptosis diabetic mellitus erectile dysfunction nitro-oleic acid NO/cGMP pathway oxidative stress