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Semi-analytical solution for mechanical analysis of tunnels crossing strike-slip fault zone considering nonuniform fault displacement and uncertain fault plane position

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Journal of Central South University 2024年第6期31卷 2116-2136页

作者： YANG Heng-hong WANG Ming-nian YU Li ZHANG Xiao school of Civil Engineering Southwest Jiaotong UniversityChengdu 610036China State Key Laboratory of Intelligent geotechnics and Tunnelling Southwest Jiaotong UniversityChengdu 610036China

The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic *** existing analysis models frequently assume uniform fault displacement and fixed fault plane *** contrast,post-earthquake observations indicate that the displacement near the fault zone is typically nonuniform,and the fault plane position is *** this study,we first established a series of improved governing equations to analyze the mechanical response of tunnels under strike-slip fault *** proposed methodology incorporated key factors such as nonuniform fault displacement and uncertain fault plane position into the governing equations,thereby significantly enhancing the applicability range and accuracy of the *** contrast to previous analytical models,the maximum computational error has decreased from 57.1%to 1.1%.Subsequently,we conducted a rigorous validation of the proposed methodology by undertaking a comparative analysis with a 3D finite element numerical model,and the results from both approaches exhibited a high degree of qualitative and quantitative agreement with a maximum error of 9.9%.Finally,the proposed methodology was utilized to perform a parametric analysis to explore the effects of various parameters,such as fault displacement,fault zone width,fault zone strength,the ratio of maximum fault displacement of the hanging wall to the footwall,and fault plane position,on the response of tunnels subjected to strike-slip fault *** findings indicate a progressive increase in the peak internal forces of the tunnel with the rise in fault displacement and fault zone ***,an augmentation in fault zone width is found to contribute to a decrease in the peak internal *** example,for a fault zone width of 10 m,the peak values of bending moment,shear force,and axial force are approximately 46.9%,102.4%,and 28.7% higher,respectively,compared to those observed for a fault zone width of 50 ***,the

关键词： strike-slip fault tunnel engineering semi-analytical solution fault zone width nonuniform fault displacement uncertain fault plane position

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Machine learning prediction of methane,ethane,and propane solubility in pure water and electrolyte solutions:Implications for stray gas migration modeling

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Acta Geochimica 2024年第5期43卷 971-984页

作者： Ghazal Kooti Reza Taherdangkoo Chaofan Chen Nikita Sergeev Faramarz Doulati Ardejani Tao Meng Christoph Butscher Institute of geotechnics TU Bergakademie FreibergGustav-Zeuner-Str.109599 FreibergGermany Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Freiberg Center for Water Research ZeWaF TU Bergakademie Freiberg09599 FreibergGermany school of Mining College of EngineeringUniversity of TehranTehranIran Taiyuan University of Science and Technology Taiyuan 030024China

Hydraulic fracturing is an effective technology for hydrocarbon extraction from unconventional shale and tight gas reservoirs.A potential risk of hydraulic fracturing is the upward migration of stray gas from the deep subsurface to shallow *** stray gas can dissolve in groundwater leading to chemical and biological reactions,which could negatively affect groundwater quality and contribute to atmospheric *** knowledge oflight hydrocarbon solubility in the aqueous environment is essential for the numerical modelling offlow and transport in the ***,we compiled a database containing 2129experimental data of methane,ethane,and propane solubility in pure water and various electrolyte solutions over wide ranges of operating temperature and *** machine learning algorithms,namely regression tree(RT)and boosted regression tree(BRT)tuned with a Bayesian optimization algorithm(BO)were employed to determine the solubility of *** predictions were compared with the experimental data as well as four well-established thermodynamic *** analysis shows that the BRT-BO is sufficiently accurate,and the predicted values agree well with those obtained from the thermodynamic *** coefficient of determination(R2)between experimental and predicted values is 0.99 and the mean squared error(MSE)is 9.97×10^(-8).The leverage statistical approach further confirmed the validity of the model developed.

关键词： Gas solubility Hydraulic fracturing Thermodynamic models Regression tree Boosted regression tree Groundwater contamination

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Enhancement of the Antigenotoxic and Antioxidant Actions of Eugenol from Spice Clove and the Stabilizer Gum Arabic on Colorectal Carcinogenesis

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Food and Nutrition Sciences 2024年第1期15卷 71-100页

作者： Nayanna de Oliveira Ramos Melo Lucas Gabriel da Costa Marques Humberto Maia Costa Neto Matheus De Sousa Silva Francisco Vagnaldo Fechine Jamacaru Bruno Coêlho Cavalcanti Antônio Adailson De Sousa Silva Conceição Aparecida Dornelas Postgraduate Program in Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil school of Medicine Federal University of Ceará Fortaleza Brazil nucleus of Research and Development of Medicines (NPDM) Laboratory of Pharmacology and Preclinical Research School of Medicine Federal University of Ceará Fortaleza Brazil nucleus for Research and Development of Medicines (NPDM) National Laboratory of Experimental Oncology Federal University of Ceará Fortaleza Brazil Postgraduate Program in Pathology and Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil

Spices are defined as any aromatic condiment of plant origin used to alter the flavor and aroma of foods. Besides flavor and aroma, many spices have antioxidant activity, mainly related to the presence in cloves of phenolic compounds, such as flavonoids, terpenoids and eugenol. In turn, the most common uses of gum arabic are in the form of powder for addition to soft drink syrups, cuisine and baked goods, specifically to stabilize the texture of products, increase the viscosity of liquids and promote the leavening of baked products (e.g., cakes). Both eugenol, extracted from cloves, and gum arabic, extracted from the hardened sap of two species of the Acacia tree, are dietary constituents routinely consumed virtually throughout the world. Both of them are also widely used medicinally to inhibit oxidative stress and genotoxicity. The prevention arm of the study included groups: Ia, IIa, IIIa, Iva, V, VI, VII, VIII. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA, EUG, or 10% GA + EUG by gavage. The treatment arm of the study included groups Ib, IIb, IIIb e IVb, IX, X, XI, XII). Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG by gavage. The novelty of this study is the investigation of their use alone and together for the prevention and treatment of experimental colorectal carcinogenesis induced by dimethylhydrazine. Our results show that the combined use of 10% gum arabic and eugenol was effective, with antioxidant action in the colon, as well as reducing oxidative stress in all colon segments and preventing and treating genotoxicity in all colon segments. Furthermore, their joint administration reduced the number of aberrant crypts and th

关键词： Eugenol Gum Arabic Carcinogenesis Oxidative Stress Genotoxicity

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Dynamic analysis of beta oscillations in Parkinsonian neural networks with the pedunculopontine nucleus under optogenetic control

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Acta Mechanica Sinica 2024年第6期40卷 125-140页

作者： Yuzhi Zhao Honghui Zhang Ying Yu Lin Du Zichen Deng school of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710072China school of Aeronautic Science and Engineering Beihang UniversityBeijing100191China school of Aeronautics Northwestern Polytechnical UniversityXi’an710072China

Clinical experiments have proven that the pedunculopontine nucleus(PPN)plays a crucial role in the modulation of beta oscillations in Parkinson’s disease(PD).Here,we propose a new computational framework by introducing the PPN and related synaptic connections to the classic basal ganglia-thalamo-cortical ***,the improved model can not only simulate the basic saturated and beta activities mentioned in previous studies but also produce the normal alpha rhythm that is much closer to physiological ***,the results show that Parkinsonian oscillation activities can be controlled and modulated by the connection strength between the PPN and the globus pallidus internal nucleus(GPi)and the subthalamic nucleus(STN),supporting the fact that PPN is overinhibited in ***,the internal mechanism underlying these state transitions is further explained from the perspective of ***,both deep brain stimulation(DBS)and optogenetic technology are considered effective in terms of abnormal *** when a low-frequency DBS is added to the PPN,beta oscillations can be suppressed,but it is excited again as the DBS’s frequency gradually increases to a larger *** results coincide with the experimental results that low-frequency stimulation of the PPN is effective,and verify the rationality of the ***,we show that optogenetic stimulation of the globus pallidus external(GPe)expressing excitatory channelrhodopsin(ChR2)can effectively inhibit beta oscillations,whereas exciting the STN and PPN has a limited *** results are consistent with experimental reports suggesting that the symptoms of PD’s movement disorder can be alleviated under the GPe-ChR2,but not STN-ChR2,*** the functional role of the PPN and the feasibility of optogenetic stimulation remain to be clinically explored,the results obtained help us understand the mechanisms of beta oscillations in PD.

关键词： Pedunculopontine nucleus Beta oscillations Optogenetic Deep brain stimulation Parkinson’s disease

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Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions

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Nuclear Science and Techniques 2024年第1期35卷 134-144页

作者： Yi-Ping Xu Si-Lu Chen Dan-Yang Pang school of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China school of Physics Beihang UniversityBeijing 100191China

The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave *** target nuclei included both stable and unstable nuclei,and the incident energies reached 200 *** results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 ***,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive *** average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 ***,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.

关键词： Microscopic optical model potential (p,d)transfer Spectroscopic factors

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The breaking of spin symmetry in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： Zhen-Yu Zheng Shou-Wan Chen Quan Liu school of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus *** this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum *** investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative *** was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum *** increasing single-particle energy,the splitting of the resonant spin doublets widened *** escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels *** also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant *** the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant *** impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component ***,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in *** study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state.

关键词： Spin symmetry Resonant states Deformed nuclei Complex-momentum representation

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Damage detection on framed structures: modal curvature evaluation using Stockwell Transform under seismic excitation

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 265-274页

作者： R.Ditommaso F.C.Ponzo G.Auletta Department of Structures Geotechnics Engineering Geology University of Basilicata school of Engineering University of Basilicata

The key parameters for damage detection and localization are eigenfrequencies, related equivalent viscous damping factors and mode shapes. The classical approach is based on the evaluation of these structural parameters before and after a seismic event, but by using a modern approach based on time-frequency transformations it is possible to quantify these parameters throughout the ground shaking phase. In particular with the use of the S-Transform, it is possible to follow the temporal evolution of the structural dynamics parameters before, during and after an earthquake. In this paper, a methodology for damage localization on framed structures subjected to strong motion earthquakes is proposed based on monitoring the modal curvature variation in the natural frequency of a structure. Two examples of application are described to illustrate the technique: Computer simulation of the nonlinear response of a model, and several laboratory(shaking table) tests performed at the University of Basilicata(Italy). Damage detected using the proposed approach and damage revealed via visual inspections in the tests are compared.

关键词： damage detection S-transform band-variable fi lter

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Different coalescence sources of light nucleus production in Au-Au collisions at √sNN=3 GeV

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Chinese Physics C 2024年第5期48卷 160-179页

作者：王瑞芹吕济鹏李彦豪宋军邵凤兰 school of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China school of Physical Science and Intelligent Engineering Jining UniversityJining 273155China

We study the production of light nuclei in the coalescence mechanism of Au-Au collisions at midrapidity at √sNN=*** derive analytic formulas of the momentum distributions of two bodies,three bodies,and four nucleons coalescing into light nuclei and naturally explain the transverse momentum spectra of the deuteron(d),triton(t),helium-3(3He),and helium-4(4He).We reproduce data on the yield rapidity densities,yield ratios,and averaged transverse momenta of d,t,3He,and 4He and provide the proportions of contributions from different coalescence sources for t,3He,and 4He in their *** find that besides nucleon coalescence,nucleon+nucleus coalescence and nucleus+nucleus coalescence may play requisite roles in light nucleus production in Au-Au collisions at √sNN=3 GeV.

关键词： light nucleus production the coalescence model relativistic heavy ion collision

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Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： Jiang-jing Wu Xi-zhou Kai Chuang Guan Yu-tao Zhao school of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

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Brain regulates weight bearing bone through PGE2 skeletal interoception: implication of ankle osteoarthritis and pain

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Bone Research 2024年第1期12卷 107-121页

作者： Feng Gao Qimiao Hu Wenwei Chen Jilong Li Cheng Qi Yiwen Yan Cheng Qian Mei Wan James Ficke Junying Zheng Xu Cao Department of Orthopedic Surgery Johns Hopkins University School of MedicineBaltimoreMaryland 21205USA Department of Biomedical Engineering Johns Hopkins University School of MedicineBaltimoreMaryland 21205USA

Bone is a mechanosensitive tissue and undergoes constant remodeling to adapt to the mechanical loading ***,it is unclear whether the signals of bone cells in response to mechanical stress are processed and interpreted in the *** this study,we found that the hypothalamus of the brain regulates bone remodeling and structure by perceiving bone prostaglandin E2(PGE2)concentration in response to mechanical *** PGE2 levels are in proportion to their weight *** weight bearing changes in the tail-suspension mice,the PGE2 concentrations in bones change in line with their weight bearing *** of cyclooxygenase-2(COX2)in the osteoblast lineage cells or knockout of receptor 4(EP4)in sensory nerve blunts bone formation in response to mechanical ***,knockout of TrkA in sensory nerve also significantly reduces mechanical load-induced bone ***,mechanical loading induces cAMP-response element binding protein(CREB)phosphorylation in the hypothalamic arcuate nucleus(ARC)to inhibit sympathetic tyrosine hydroxylase(TH)expression in the paraventricular nucleus(PVN)for ***,we show that elevated PGE2 is associated with ankle osteoarthritis(AOA)and ***,our data demonstrate that in response to mechanical loading,skeletal interoception occurs in the form of hypothalamic processing of PGE2-driven peripheral signaling to maintain physiologic bone homeostasis,while chronically elevated PGE2 can be sensed as pain during AOA and implication of potential treatment.

关键词： pain elevated PGE2

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