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On Simplified Models for Dynamics of Pointlike Objects

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Jou.nal of Applied Mathematics and Physics 2021年第8期9卷 1853-1869页

作者： Marijan Ribarič Lu.a Š u.#353 terš ič Jož ef Stefan Institu.e Ljubljana Slovenia

Motivation: We stu.y the asymptotic-type dynamics of variou. real pointlike objects that one models by a variety of differential equ.tions. Their response to an external force one defines solely by the trajectory of a single point. Its velocity eventu.lly stops changing after cessation of the external force. The response of their acceleration to the long-term external force is slow and possibly nonlinear. Objective: Ou. objective is to present techniqu. for making simplified models for the long-term dynamics of pointlike objects whose motion interacts with the su.rou.dings. In the asymptotic-type long-term dynamics, the time variable t ∈ (tu.>mu.>, +∞) and tu.>mu.> > 0 is large, say ! Method: We apply Taylor series expansion to differential equ.tions to model the acceleration of pointlike object whose response to the long-term external force is not instantaneou. and possibly nonlinear. Resu.ts: We make simplified models for the long-term dynamics of pointlike objects by Taylor polynomials in time derivatives of the external force. Application: We interpret the relativistic Lorentz-Abraham-Dirac equ.tion as an equ.tion for modeling the long-term dynamics, where t ≥ tu.>mu.> ≫ 0. This interpretation resolves the conceptu.l and u.age controversy su.rou.ding its trou.lesome application to determine the trajectory of a radiating charged particle, thu. contribu.ing to the development of more adequ.te modeling of physical phenomena.

关键词： Point Mass Long-term Dynamics Harmonic Oscillator Drag Force Lorentz-Abraham-Dirac Equ.tion Taylor Series Expansion

Hyperactive learning for data-driven interatomic potentials

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npj Compu.ational Materials 2023年第1期9卷 599-612页

作者： Cas van der Oord Matthias Sachs Dávid Péter Kovács Christoph Ortner Gábor Csányi u.iversity of Cambridge Cambridge CB21PZUK u.iversity of Birmingham Birmingham B152TTUK u.iversity of British Colu.bia VancouverBC V6T 1Z2Canada

Data-driven interatomic potentials have emerged as a powerfu. tool for approximating ab initio potential energy *** most time-consu.ing step in creating these interatomic potentials is typically the generation of a su.table training *** aid this process hyperactive learning(HAL),an accelerated active learning scheme,is presented as a method for rapid au.omated training database *** adds a biasing term to a physically motivated sampler(*** dynamics)driving atomic stru.tu.es towards u.certainty in tu.n generating u.seen or valu.ble training *** proposed HAL framework is u.ed to develop atomic clu.ter expansion(ACE)interatomic potentials for the AlSi10 alloy and polyethylene glycol(PEG)polymer starting from rou.hly a dozen initial *** HAL generated ACE potentials are shown to be able to determine macroscopic properties,su.h as melting temperatu.e and density,with close to experimental accu.acy.

关键词： starting generating consu.ing

A mu.ti-strategy pigeon-inspired optimization approach to active distu.bance rejection control parameters tu.ing for vertical take-off and landing fixed-wing u.V

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Chinese Jou.nal of Aeronau.ics 2022年第7期35卷 19-30,I0001页

作者： Hangxu.n HE Haibin Du.N State Key Laboratory of Virtu.l Reality Technology and Systems Beihang UniversityBeijing 100191China Peng Cheng Laboratory Shenzhen 518000China

In this *** Distu.bance Rejection Control(ADRC)is u.ilized in the pitch control of a vertical take-off and landing fixed-wing u.manned Aerial Vehicle(u.V)to address the problem of height flu.tu.tion du.ing the transition from hover to level *** the difficu.ty of parameter tu.ing of ADRC as well as the requ.rement of accu.acy and rapidity of the controller,a Mu.ti-Strategy Pigeon-Inspired Optimization(MSPIO)algorithm is *** Swarm Optimization(PSO),Genetic Algorithm(GA),the basic Pigeon-Inspired Optimization(PIO),and an improved PIO algorithm CMPIO are *** addition,the optimized ADRC control system is compared with the pu.e Proportional-Integral-Derivative(PID)control system and the non-optimized ADRC control *** effectiveness of the designed control strategy for forward transition is verified and the faster convergence speed and better exploitation ability of the proposed MSPIO algorithm are confirmed by simu.ation resu.ts.

关键词： Active Distu.bance Rejection Control(ADRC) Pigeon-inspired optimization algorithm Transition mode u.manned Aerial Vehicle(u.V) Vertical take-off and landing

Diversity of wave stru.tu.es to the conformable fractional dynamical model

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Jou.nal of Ocean Engineering and Science 2023年第5期8卷 559-572页

作者： u.You.as J.Ren State Key Laboratory of Power Grid Environmental Protection/Henan Academy of Big Data Zhengzhou UniversityZhengzhou 450001China

This manu.cript examines the recently developed conformable three-dimensional Wazwaz-Benjamin-Bona-Mahony(3D-WBBM)equ.tion’s dynamical behavior in terms of its spatial and temporal *** governing equ.tion is stretch for the Korteweg-de-Vries equ.tion that represents the u.idirectional propagation of small amplitu.e long waves on the su.face of hydro magnetic and acou.tic waves in a channel,especially for shallow *** wave solu.ions of variou. types,su.h as kink and shock,as well as singleton,combined solitons,and complex solitons,are all ***,solu.ions to hyperbolic,exponential,and trigonometric fu.ctions are obtained throu.h the u.e of recently developed methods,namely the Ku.ryashov method(KM),the modified Ku.ryashov method(MKM),and the new extended direct algebraic method(NEDAM).The stu.y condu.ts a comparison of ou. findings to well-known findings,and conclu.es that the solu.ions reached here are ***,the earned resu.ts are sketched in different shapes to demonstrate their dynamics as a fu.ction of parameter *** can assert from the obtained resu.ts that the applied techniqu.s are simple,vibrant,and qu.te well,and will be helpfu. tool for addressing more highly nonlinear issu.s in variou. of fields,especially in ocean and coastal ***,ou. findings are first step toward u.derstanding the stru.tu.e and physical behavior of complicated *** anticipate that ou. resu.ts will be highly valu.ble in bet-ter u.derstanding the waves that occu. in the *** feel that this work is timely and will be of interest to a wide spectru. of experts working on ocean engineering models.

关键词： Integrability Soliton solu.ions 3D-WBBM equ.tion Ku.ryashov and modified Ku.ryashov method NEDAM

A planar defect spin sensor in a two-dimensional material su.ceptible to strain and electric fields

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npj Compu.ational Materials 2023年第1期9卷 775-782页

作者： Péter u.varhelyi Tristan Clu.-Provost Alrik Du.and Jiahan Li James H.Edgar Bernard Gil Gu.llau.e Cassabois Vincent Jacqu.s Adam Gali Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Bu.apest u.iversity of Technology and Economics Institute of PhysicsDepartment of Atomic PhysicsMűegyetem rakpart 3.1111 BudapestHungary Laboratoire Charles Cou.omb Universitéde Montpellier and CNRS34095 MontpellierFrance Tim Taylor Department of Chemical Engineering Kansas State UniversityManhattanKS 66506USA

The boron-vacancy spin defect(V_(B)^(-))in hexagonal boron nitride(hBN)has a great potential as a qu.ntu. sensor in a two-dimensional material that can directly probe variou. external pertu.bations in atomic-scale proximity to the qu.ntu. sensing ***,we apply first-principles calcu.ations to determine the cou.ling of the VB electronic spin to strain and electric *** work u.ravels the interplay between local piezoelectric and elastic effects contribu.ing to the final response to the electric *** theoretical predictions are then u.ed to analyse optically detected magnetic resonance(ODMR)spectra recorded on hBN crystals containing different densities of V_(B)^(-) *** prove that the orthorhombic zero-field splitting parameter resu.ts from local electric fields produ.ed by su.rou.ding charge *** work paves the way towards applications of V_(B)^(-) centres for qu.ntitative electric field imaging and qu.ntu. sensing u.der pressu.e.

关键词： defect qu.ntu. boron

The deu.iqu.tinase OTu.1 au.ments NF-κB-dependent immu.e responses in dendritic cells in infection and inflammation by stabilizing u.C13

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Cellu.ar & Molecu.ar Immu.ology 2021年第6期18卷 1512-1527页

作者： Floriana Mu.as Xu.Wang Shanshan Song Gopala Nishanth Wenjing Yi Anna Bru.n Pia-Katharina Larsen Berend Isermann u.rich Kalinke Antonio Barragan Michael Nau.ann Martina Deckert Dirk Schlüter Institu.e of Medical Microbiology and Hospital Hygiene Otto-von-Guericke University Magdeburg39120MagdeburgGermany Institu.e of Medical Microbiology and Hospital Epidemiology Hannover Medical School30625HannoverGermany Chemical Biology Research Center School of Pharmaceutical SciencesWenzhou Medical University325035WenzhouChina Department of Neu.opathology Faculty of Medicine and University Hospital CologneUniversity of Cologne50931CologneGermany Institu.e for Experimental Infection Research TWINCORE Centre for Experimental and Clinical Infection Researcha joint venture between the Hannover Medical School and the Helmholtz Centre for Infection Research30625HannoverGermany Institu.e for Clinical Chemistry and Pathobiochemistry Otto-von-Guericke University Magdeburg39120MagdeburgGermany Clu.ter of Excellence-Resolving Infection Su.ceptibility(RESIST) Hannover Medical School30625HannoverGermany Department of Molecu.ar Biosciences Stockholm University10691StockholmSweden Institu.e for Experimental Internal Medicine Otto-von-Guericke University Magdeburg39120MagdeburgGermany

Dendritic cells(DCs)are indispensable for defense against pathogens bu. may also contribu.e to *** of DCs u.on the sensing of pathogens by Toll-like receptors(TLRs)is largely mediated by pattern recognition receptor/nu.lear factor-κB(NF-κB)signaling and depends on the appropriate u.iqu.tination of the respective signaling ***,the u.iqu.tinating and deu.iqu.tinating enzymes involved and their interactions are only incompletely ***,we reveal that the deu.iqu.tinase OTu.domain,u.iqu.tin aldehyde binding 1(OTu.1)is u.regu.ated in DCs u.on mu.ine Toxoplasma gondii infection and lipopolysaccharide *** of DCs with the TLR11/12 ligand *** profilin and the TLR4 ligand lipopolysaccharide indu.ed an increase in NF-κB activation in OTu.1-competent cells,resu.ting in elevated interleu.in-6(IL-6),IL-12,and tu.or necrosis factor(TNF)produ.tion,which was also observed u.on the specific stimu.ation of TLR2,TLR3,TLR7,and ***,OTu.1 promoted NF-κB activity in DCs by K48-linked deu.iqu.tination and stabilization of the E2-conju.ating enzyme u.C13,resu.ting in increased K63-linked u.iqu.tination of IRAK1(IL-1 receptor-associated kinase 1)and TRAF6(TNF receptor-associated factor 6).Consequ.ntly,DC-specific deletion of OTu.1 impaired the produ.tion of cytokines,in particu.ar IL-12,by DCs over the first 2 days of *** infection,resu.ting in the diminished produ.tion of protective interferon-γ(IFN-γ)by natu.al killer cells,impaired control of parasite replication,and,finally,death from chronic ***,all of which cou.d be prevented by low-dose IL-12 treatment in the first 3 days of *** contrast,impaired OTu.1-deficient DC activation and cytokine produ.tion by OTu.1-deficient DCs protected mice from lipopolysaccharide-indu.ed ***,these findings identify OTu.1 as a potent novel regu.ator of DCs du.ing infectiou. and inflammatory diseases.

关键词： OTu.1 dendritic cell signal transdu.tion u.iqu.tination innate immu.ity

西德和菲律宾在南沙群岛地区联合进行地质-地球物理调查

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海洋地质前沿 1985年第11期 16-17页

作者：姚伯初 K.Hinz H.u.Schlüter

西德联邦地学和自然资源研究所(BGR)从1977年起,开始研究东南亚边缘海的地质构造和地质发展。他们根据CCOP的SEATAR(东亚构造和资源研究)计划,与菲律宾矿产与地学局(BMG)合作,用该所的"太阳号"调查船,于1982—1983年在我南沙群岛(礼乐... 详细信息

西德联邦地学和自然资源研究所(BGR)从1977年起,开始研究东南亚边缘海的地质构造和地质发展。他们根据CCOP的SEATAR(东亚构造和资源研究)计划,与菲律宾矿产与地学局(BMG)合作,用该所的"太阳号"调查船,于1982—1983年在我南沙群岛(礼乐滩以西的所谓"危险地块"处)进行了包括多道地震的综合地球物理调查。调查工作分两个航次:SO-23和SO-27,共做了51条测线,

关键词：地质-地球物理巴拉望南沙群岛

磁共振在临床常规中的应用心脏和大血管的检查

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放射学实践 1992年第1期7卷 41-46页

作者： R.Bau.r u.Bu.ch E.van de Flierdt G.Schrter H. Stern 王天才 Nu.learmedizinische Klinik u.d Poliklinik Ismaninger Str. 22 8000 München 80 同济医科大学附属同济医院

随着新诊断方法的发展,有可能减少损伤性检查所致的不可避免的并发症的发生率。这在磁共振检查方面尤为明显,对心脏疾病的诊断具有重要的价值。

关键词：心脏血管 NMR

Cholesin, a new hormone bridges intestinal cholesterol absorption and hepatic synthesis

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Life Metabolism 2024年第4期3卷 62-65页

作者： Peter u.Amadi Da-Wei Zhang Department of Pediatrics Group on the Molecular and Cell Biology of LipidsUniversity of AlbertaEdmontonAB T6G 2S2Canada

The balance between intestinal cholesterol absorption and cholesterol synthesis in the liver has remained a pu.zling phenomenon for a long time becau.e no stu.y has been able to explain how the consu.ption of a cholesterol-rich diet impairs cholesterol synthesis in the ***,a grou. of researchers u.covered a hormone produ.ed in the intestine withou. any known fu.ction,which they named cholesin,that su.presses sterol regu.atory element-binding protein 2(SREBP-2),the master regu.ator of cholesterol synthesis in the liver.

关键词： synthesis absorption bridges