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Impact of the Brink-Axel hypothesis on unique first-forbiddenβ-transitions for r-process nuclei

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Chinese Physics C 2024年第3期48卷 148-168页

作者： Fakeha Farooq Jameel-un Nabi Ramoona Shehzadi Department of Physics University of the PunjabQuaid-e-Azam Campus 54590LahorePakistan university of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

Key nuclear inputs for the astrophysical r-process simulations are the weak interaction ***,the accuracy of these inputs directly affects the reliability of nucleosynthesis *** majority of the stellar rates,used in simulation studies are calculated by invoking the Brink-Axel(BA)*** BA hypothesis assumes that the strength functions of all parent excited states are the same as for the ground state,only shifted in ***,the BA hypothesis has to be tested against microscopically calculated state-by-state *** this project,we study the impact of the BA hypothesis on calculated stellarβ^(-)-decay and electron capture *** investigation include both unique first forbidden(U1F)and allowed transitions for 106 neutron-rich trans-iron nuclei([27,77]≤[Z,A]≤[82,208]).The calculations were performed using the deformed proton-neutron quasiparticle random-phase approximation(pn-QRPA)model with a simple plus quadrupole separable and schematic ***-point and several key r-process nuclei lie within the considered mass region of the nuclear *** computed electron capture andβ^(-)-decay rates using two different prescriptions for strength *** was based on invoking the BA hypothesis and the other was the state-by-state calculation of strength functions,under stellar density and temperature conditions([10,1]≤[ρYe(g/cm^(3)),T(GK)]≤[10^(11),30]).Our results show that the BA hypothesis invoked U1Fβ^(-)rates are overestimated by 4–5 orders of magnitude as compared to microscopic *** capture rates,more than two orders of magnitude differences were noted when applying the BA *** was concluded that the BA hypothesis is not a reliable approximation,especially forβ^(-)-decay forbidden transitions.

关键词： Brink-Axel hypothesis pn-QRPA model unique first forbiddenβ-transitions GT strength functions trans-iron nuclei r-process

Protein Arginine Methyltransferase 1 Ablation in Motor Neurons Causes Mitochondrial Dysfunction Leading to Age-related Motor Neuron Degeneration with Muscle Loss

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Research 2024年第1期2023卷 637-649页

作者： Hyun-Kyung So Hyebeen Kim Jinwoo Lee Chang-Lim You Chae-Eun Yun Hyeon-Ju Jeong Eun-Ju Jin Yunju Jo Dongryeol Ryu Gyu-un Bae Jong-Sun kang Department of Molecular Cell Biology Sungkyunkwan University School of MedicineSuwonKorea Single Cell Network Research Center Sungkyunkwan University School of MedicineSuwonKorea Research Institute of Aging-Related Diseases AniMusCureInc.SuwonKorea Drug Information Research Institute Muscle Physiome Research CenterCollege of PharmacySookmyung Women’s UniversitySeoulKorea

Neuromuscular dysfunction is tightly associated with muscle wasting that occurs with age or due to degenerative ***,the molecular mechanisms underlying neuromuscular dysfunction are currently *** studies have proposed important roles of Protein arginine methyltransferase 1(Prmt1)in muscle stem cell function and muscle *** the current study,we set out to determine the role of Prmt1 in neuromuscular function by generating mice with motor neuron-specific ablation of Prmt1(mnKO)using *** exhibited age-related motor neuron degeneration and neuromuscular dysfunction leading to premature muscle loss and ***1 deficiency also impaired motor function recovery and muscle reinnervation after sciatic nerve *** transcriptome analysis of aged mnKO lumbar spinal cords revealed alterations in genes related to inflammation,cell death,oxidative stress,and ***,mnKO lumbar spinal cords of sciatic nerve injury model or aged mice exhibited elevated cellular stress response in motor ***,Prmt1 inhibition in motor neurons elicited mitochondrial *** findings demonstrate that Prmt1 ablation in motor neurons causes agerelated motor neuron degeneration attributing to muscle ***,Prmt1 is a potential target for the prevention or intervention of sarcopenia and neuromuscular dysfunction related to aging.

关键词： degeneration impaired prevention

Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： B.F.Irgaziev Abdul Kabir Jameel-un Nabi National university of Uzbekistan Tashkent 100174Uzbekistan Space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan university of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

Trace Lasso Regularization for Adaptive Sparse Canonical Correlation Analysis via Manifold Optimization Approach

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Journal of the Operations Research Society of China 2024年第3期12卷 573-599页

作者： kang-kang Deng Zheng Peng Beijing International Center for Mathematical Research Peking UniversityBeijing100871China School of Mathematics and Computational Science Xiangtan UniversityXiangtan411105China

Canonical correlation analysis(CCA)describes the relationship between two sets of variables by finding a linear combination that maximizes the correlation ***,in high-dimensional settings where the number of variables exceeds sample size,or in the case that the variables are highly correlated,the traditional CCA is no longer *** this paper,a new matrix regularization is introduced,which is an extension of the trace Lasso in the vector *** we propose an adaptive sparse version of CCA(ASCCA)to overcome these disadvantages by utilizing the trace Lasso *** adaptability of ASCCA is that the sparsity regularization of canonical vectors depends on the sample data,which is more realistic in practical *** ASCCA model is further reformulated to an optimization problem on the Riemannian *** we adopt a manifold inexact augmented Lagrangian method to solve the resulting optimization *** performance of the ASCCA model is compared with some existing sparse CCA techniques in different simulation settings and real datasets.

关键词： Canonical correlation analysis Sparsity of canonical vectors Trace Lasso regularization Manifold optimization

Effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on tensile and bending properties of high-Al-containing Mg alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 779-793页

作者： Sumi Jo Gyo Myeong Lee Jong un Lee Young Min Kim Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Magnesium Korea Institute of Materials ScienceChangwon 51508Republic of Korea

This study investigates the effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on the uniaxial tensile and three-point bending properties of extruded Mg alloys containing high Al *** extruded Mg–9Al–1Zn–0.3Mn(AZ91)alloy contains lamellar-structured Mg_(17)Al_(12)discontinuous precipitates along the grain boundaries,which are formed via static precipitation during natural air *** extruded Mg–11Al–1Zn–0.3Mn(AZ111)alloy contains spherical Mg_(17)Al_(12)precipitates at the grain boundaries and inside the grains,which are formed via dynamic precipitation during *** to inhomogeneous distribution of precipitates,the AZ111 alloy consists of two different precipitate regions:precipitate-rich region with numerous precipitates and finer grains and precipitate-scarce region with a few precipitates and coarser *** AZ111 alloy exhibits a higher tensile strength than the AZ91 alloy because its smaller grain size and more abundant precipitates result in stronger grain-boundary hardening and precipitation hardening effects,***,the tensile elongation of the AZ111 alloy is lower than that of the AZ91 alloy because the weak cohesion between the dynamic precipitates and the matrix facilitates the crack initiation and *** bending,a macrocrack initiates on the outer surface of bending specimen in both *** AZ111 alloy exhibits higher bending yield strength and lower failure bending strain than the AZ91 *** bending specimens of the AZ91 alloy have similar bending formability,whereas those of the AZ111 alloy exhibit considerable differences in bending formability and crack propagation behavior,depending on the distribution and number density of precipitates in the *** bending specimens of the AZ111 alloy,it is found that the failure bending strain(ε_(f,bending))is inversely proportional to the area fraction of precipitates in the outer zone of bending specimen(A_(ppt)),with a relation

关键词： Mg–Al alloy Extrusion Bending Precipitation Microstructure

Re-analysis of temperature dependent neutron capture rates and stellarβ-decay rates of^(95-98)Mo

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Chinese Physics C 2024年第9期48卷 142-149页

作者： Abdul Kabir Jameel-un Nabi Muhammad Tahir Abdul Muneem Zain Ul Abideen Space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan university of Wah Quaid AvenueWah Cantt 47040PunjabPakistan Faculty of Engineering Sciences GIK Institute of Engineering Sciences and TechnologyTopi 23640Khyber PakhtunkhwaPakistan

The neutron capture rates and temperature dependent stellar beta decay rates of Mo isotopes are investigated within the framework of the statistical code TALYS v1.96 and the proton neutron quasi particle random phase approximation(pn-QRPA)*** Maxwellian average cross-section(MACS)and neutron capture rates for the^(95-98)Mo(n,γ)^(96-99)Mo radiative capture process are analyzed within the framework of the statistical code TALYS v1.96 based on the phenomenological nuclear level density model and gamma strength *** present model-based computations for the MACS are comparable to the existing measured *** sensitivity of stellar weak interaction rates to various densities and temperatures is investigated within the framework of the pn-QRPA *** attention is paid to the impact of thermally filled excited states in the decaying nuclei(^(95-98)Mo)on electron emission and positron capture ***,we compare the neutron capture rates and stellar beta decay *** is found that neutron capture rates are higher than stellar beta decay rates at both lower and higher temperatures.

关键词： cross-section TALYS nuclear level density decay rates capture rates

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： Bin ZHOU Yi DING kang-kang ZHANG Guang-Ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

Progress in the application of polymer fibers in solid electrolytes for lithium metal batteries

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Journal of Energy Chemistry 2024年第5期92卷 26-42页

作者： Junbao kang Nanping Deng Bowen Cheng Weimin kang State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes School of Textile Science and EngineeringTiangong UniversityTianjin 300387China

Solid state lithium metal batteries(SSLMBs)are considered to be one of the most promising battery systems for achieving high energy density and excellent safety for energy storage in the ***,current existed solid-state electrolytes(SSEs)are still difficult to meet the practical application requirements of *** this review,based on the analysis of main problems and challenges faced by the development of SSEs,the ingenious application and latest progresses including specific suggestions of various polymer fibers and their membrane products in solving these issues are emphatically ***,the inherent defects of inorganic and organic electrolytes are pointed ***,the application strategies of polymer fibers/fiber membranes in strengthening strength,reducing thickness,enhancing thermal stability,increasing the film formability,improving ion conductivity and optimizing interface stability are discussed in detail from two aspects of improving physical structure properties and electrochemical ***,the researches and development trends of the intelligent applications of high-performance polymer fibers in SSEs is *** review intends to provide timely and important guidance for the design and development of polymer fiber composite SSEs for SSLMBs.

关键词： Composite solide lectrolytes Polymer fibers Solid-state lithium metal batteries Solid-stateel ectrolytes Nanofiber membranes

Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing He Le kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect *** RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation