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Spinal intradural electrodes: opportunities, challenges and translation to the clinic

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Neural Regeneration Research 2024年第3期19卷 503-504页

作者： Bruce Harland Chien yew Kow Darren Svirskis School of Pharmacy University of AucklandAucklandNew Zealand Department of Neurosurgery Auckland City HospitalAucklandNew Zealand

Damage to the spinal cord disrupts the electrically active nerve cells which normally transmit afferent and efferent signals,resulting in loss of motor,sensory,and autonomic *** treatments for spinal cord injury utilizing implanted spinal electrodes can be broadly classified into three different *** first of these approaches is“spinal stimulation”where electrodes,usually positioned above the level of injury,provide electrical stimulation to target and disrupt pain signals before they reach the *** second approach uses“activity-dependent neuro-technologies”,in which electrodes positioned below the level of injury initiate a complex spatiotemporal pattern of stimulation at the lumbar spinal cord to generate a walking gait in the limbs(Minev et al.,2015;wagner et al.,2018).

关键词： stimulation electrodes utilizing

Superexchange and charge transfer in the nickelate superconductor La_(3)Ni_(2)O_(7) under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 1-8页

作者： wéi wú Zhihui Luo Dao-Xin Yao Meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Recently, a bulk nickelate superconductor La_(3)Ni_(2)O_(7) is discovered at pressures with a remarkable high transition temperature T_(c)~ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La_(3)Ni_(2)O_(7),by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d_(3z^(2)-r^(2)) and O-p_(z) orbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-d_(x^(2)-y^(2)) and O-p_(x)/p_(y) orbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the d_(x^(2)-y^(2)) and p_(x)/p_(y) orbitals, whereas the d_(3z^(2)-r^(2)) and p_(z) orbitals retain underdoped. we propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La_(3)Ni_(2)O_(7) superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Pervasive Attentive Neural Network for Intelligent Image Classification Based on N-CDE’s

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Computers, Materials & Continua 2024年第4期79卷 1137-1156页

作者： Anas w.Abulfaraj Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityRabigh21911Saudi Arabia

The utilization of visual attention enhances the performance of image classification *** attentionbased models have demonstrated notable performance,but many of these models exhibit reduced accuracy when confronted with inter-class and intra-class similarities and ***-Controlled Differential Equations(N-CDE’s)and Neural Ordinary Differential Equations(NODE’s)are extensively utilized within this ***’s possesses the capacity to effectively illustrate both inter-class and intra-class similarities and differences with enhanced *** this end,an attentive neural network has been proposed to generate attention maps,which uses two different types of N-CDE’s,one for adopting hidden layers and the other to generate attention *** distinct attention techniques are implemented including time-wise attention,also referred to as bottom N-CDE’s;and element-wise attention,called topN-CDE’***,a trainingmethodology is proposed to guarantee that the training problem is sufficiently *** classification tasks including fine-grained visual classification andmulti-label classification,are utilized to evaluate the *** proposedmethodology is employed on five publicly available datasets,including CUB-200-2011,ImageNet-1K,PASCAL VOC 2007,PASCAL VOC 2012,and MS *** obtained visualizations have demonstrated that N-CDE’s are better appropriate for attention-based activities in comparison to conventional NODE’s.

关键词： Differential equations neural-controlled DE image classification attention maps N-CDE’s

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H w A Riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Recent Advances in the Synthesis and Polymerization of New CO_(2)-Based Cyclic

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Chinese Journal of Chemistry 2024年第4期42卷 430-443页

作者： Matteo Lanzi Arjan w.Kleij Institute of Chemical Research of Catalonia(ICIQ) The Barcelona Institute of Science and Technology(BIST)Av.Països Catalans 1643007 TarragonaSpain Catalan Institute of Research and Advanced Studies(ICREA) Pg.Lluís Companys 2308010 BarcelonaSpain

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering *** minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based *** addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate *** perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

关键词： Carbon dioxide Cyclic carbonates Functional macromolecules Heterocycles Polycarbonates Recycling Ring opening polymerization

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.w.wi Y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths

p-wave resonances in the exponential cosine screened Coulomb potential

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Communications in Theoretical Physics 2024年第7期76卷 105-113页

作者： Yuan-Cheng wang Li Guang Jiao Aihua Liu yew Kam Ho Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China College of Physics Jilin UniversityChangchun 130012China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum fur Schwerionenforschung GmbH D-64291 DarmstadtGermany Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Institute of Atomic and Molecular Sciences Academia SinicaTaipei 10617TaiwanChina

we perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral *** present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous *** is found that the resonance states approximately follow an n^(2)-scaling law which is similar to the bound *** birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.

关键词： complex-scaling method shape resonance generalized pseudospectral method exponential cosine screened Coulomb potential

Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.Johnson Robert C.Burghardt Fuller w.Bazer Heewon Seo Joe w.Cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the sc

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep