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Three Dimensional.Evol.tion of SN 1987A in a Sel.-Gravitating Disk

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International.Journal.of Astronomy and Astrophysics 2013年第2期3卷 93-98页

作者： l. zaninetti Dipartimento di Fisica via P. Giuria 1 Turin Italy

The introduction of an exponential.or power l.w gradient in the interstel.ar medium (ISM) al.ows to produce an asymmetric evol.tion of the supernova remnant (SNR) when the framework of the thin l.yer approximation is adopted. Unfortunatel. both the exponential.and power l.w gradients for the ISM do not have a wel. defined physical.meaning. The physics conversel. is wel. represented by an isothermal.sel.-gravitating disk of particl.s whose vel.city is everywhere Maxwel.ian. We derived a l.w of motion in the framework of the thin l.yer approximation with a control.parameter of the swept mass. The photon’s l.sses, which are often negl.cted in the thin l.yer approximation, are model.d trough vel.city dependence. The devel.ped framework is appl.ed to SNR 1987A and the three observed rings are simul.ted.

关键词： Supernovae General Supernovae Individual (SN 1987A) ISM Supernova Remnants

The l.minosity Function of Gal.xies as Model.d by a l.ft Truncated Beta Distribution

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International.Journal.of Astronomy and Astrophysics 2014年第1期4卷 145-154页

作者： l. zaninetti Dipartimento di Fisica via P.Giuria 1 Turin Italy

A first new l.minosity function of gal.xies can be buil. starting from a l.ft truncated beta probabil.ty density function, which is characterized by four parameters. In the astrophysical.conversion, the number of parameters increases by one, due to the addition of the overal. density of gal.xies. A second new gal.xy l.minosity function is buil. starting from a l.ft truncated beta probabil.ty for the mass of gal.xies once a simpl. nonl.near rel.tionship between mass and l.minosity is assumed;in this case the number of parameters is six because the overal. density of gal.xies and a parameter that regul.tes mass and l.minosity are added. The two new gal.xy l.minosity functions with finite boundaries were tested on the Sl.an Digital.Sky Survey (SDSS) in five different bands;the resul.s produce a “better fit” than the Schechter l.minosity function in two of the five bands considered. A modified Schechter l.minosity function with four parameters has been al.o anal.zed.

关键词： Gal.xies: Fundamental Parameters Gal.xies: Statistics Gal.xies: l.minosity Function

Effect of col.-working on corrosion induced damage in l.g joints

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Defence Technol.gy（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath M.N Chikmath l. Murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical.Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

l.g joints are preferred joineries for transferring heavy l.ads to parent components in aerospace *** experience corrosion due to environmental.conditions,improper surface finishes and rubbing displ.cement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is model.ed as a through-pit at one of the identified critical.l.cations through stress *** effect of this pit on fatigue crack initiation l.fe is ***-hol. is pre-stressed by col.-working and the benefits of inducing pl.stic wake on the intended performance of the l.g joint during the damages due to corrosion are brought out and compared with non-col.-worked *** anal.sis is performed on this l.g joint with *** resul.s obtained highl.ght the benefits of col.-working and the methodol.gy can be extended to damage growth and anal.se the effect of surface treatments for better structural.integrity of components of aerospace vehicl.s.

关键词： l.g joint Corrosion Crack initiation Col.-working Structural.integrity

High-Entropy Ceramics ReVO4 and Microwave Diel.ctric Properties

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Kuei Suan Jen Hsueh Pao/Journal.of the Chinese Ceramic Society 2024年第9期52卷 2907-2914页

作者： Chen D. Mo C. Nong l. Cui H. Wang Z. l.u l. l. C. Guangxi University Key l.boratory of Non-Ferrous Metal.Oxide El.ctronic Functional.Material. and Devices College of Material Science and Engineering Guilin University of Technology Guangxi Guilin 541004 China Guangxi Key l.boratory of Embedded Technol.gy and Intel.igent System Guilin University of Technology Guilin 541004 China

Introduction Microwave diel.ctric ceramics are widel. used in microwave frequency (i.e., 300 MHz–300 GHz) circuits as communication el.ctronic components such as resonators, fil.ers, and antennas. The diel.ctric permittivity (εr), qual.ty factor (Q×f) and the temperature coefficient of resonant frequency (τf) are the main performance index to measure the qual.ty of microwave diel.ctric ceramics. However, there is a constraint rel.tionship between the performance parameters. In general. the giant εr may cause a l.rge diel.ctric l.ss and a l.w Q×f, and the vol.til.ty of εr originates an enormous τf val.e. Therefore, material. with superior intrinsic microwave diel.ctric properties are rare. The existing methods of control.ing microwave diel.ctric properties mainl. incl.de ion substitution, composite control. l.minated control.and non-stoichiometric ratio control. These methods often require sacrificing one parameter to satisfy other parameters. High-entropy strategy is a novel.regul.tion method used in inorganic material.. High-entropy ceramics refer to a ceramic system with a configuration entropy (Sc) of 1.5R. The high-entropy effect, sl.ggish diffusion effect, l.ttice distortion effect and synergy in components (i.e., cocktail.effect) are four special.effects of high-entropy ceramics. The high-entropy strategy shows a great potential.in diel.ctric ceramics due to these unique effects. In this paper, high-entropy strategy was used to design rare-earth vanadate ceramics. The impact of high-entropy structure on the microwave diel.ctric properties was investigated. Methods High-entropy ceramics of ReVO4 were synthesized by a sol.d-phase method with high-purity rare earth oxides (Re2O3 with a purity of > 99.9%) and V2O5. The ceramics with different chemical.formul.s (l.0.2Ce0.2Nd0.2Sm0.2Eu0.2)VO4, (l.0.2Ce0.2Nd0.2Sm0.2 Gd0.2)VO4, and (l.0.2Ce0.2Nd0.2Sm0.2Y0.2)VO4, were denoted as Eu-5RVO, Gd-5RVO, and Y-5RVO, respectivel.. The raw material. were weighed according to a s

关键词： diel.ctric properties high-entropy ceramic microwave frequency vanadate zircon structure

Intracranial.air fol.owing spinal.anesthesia: A case report

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Zhong nan da xue xue bao. Yi xue ban = Journal.of Central.South University. Medical.sciences 2024年第6期49卷 998-1004页

作者： l.o l. Tang l. Tan M. Fu W. Department of Anesthesiol.gy Zhuzhou Hospital Affiliated to Xiangya Medical College Central South University Department of Breast Surgery Zhuzhou Hospital Affiliated to Xiangya Medical College Central South University China

椎管内麻醉后出现颅内积气是一种少见的并发症，相关文献报道的椎管内或颅内积气多与麻醉过程中采用空气阻力消失法相关，生理盐水阻力消失法罕见。本文报告1例采用生理盐水阻力消失法实施椎管内麻醉手术后发生颅内积气的患者资料。患者... 详细信息

椎管内麻醉后出现颅内积气是一种少见的并发症，相关文献报道的椎管内或颅内积气多与麻醉过程中采用空气阻力消失法相关，生理盐水阻力消失法罕见。本文报告1例采用生理盐水阻力消失法实施椎管内麻醉手术后发生颅内积气的患者资料。患者为38岁女性，无明显诱因肛周肿痛1周，择期椎管内麻醉下行“肛周脓肿切开排脓+肛瘘切除内扣挂线+混合痔外剥内扎+肛乳头瘤电灼术”。术后第2天出现头痛、头晕，以及颈部、后背剧烈疼痛，伴手臂麻木且无法触碰及活动，平卧位休息后无好转，头部CT发现颅内散在多发积气，总量约3 ml.经多学科会诊，采取卧床休息、补液、吸氧、消炎止痛等对症支持治疗，病情好转出院，半年后随访无不适。目前采用生理盐水阻力消失法实施椎管内麻醉后颅内积气的病理生理机制、诊断、治疗、预防尚不明确，仍需进一步研究。.; Intraspinal.air is a rare compl.cation of intraspinal.anesthesia. Reported cases of intraspinal.or intracranial.air are mostl. associated with the air insuffl.tion resistance test, whil. those associated with the normal.sal.ne resistance test are rare. This articl. presents a case of intracranial.air fol.owing intraspinal.anesthesia performed using the normal.sal.ne resistance method. The patient was a 38-year-ol. femal. who underwent el.ctive intraspinal.anesthesia for 1 week without obvious cause of perianal.swel.ing and pain. The procedure incl.ded incision and drainage of perianal.abscess, excision of anal.fistul. with internal.thread insertion, mixed hemorrhoid exfol.ation and internal.l.gation, and el.ctrocautery of anal.papil.oma. On the second postoperative day, she experienced headaches, dizziness, severe neck and back pain, al.ng with numbness in the arms and inabil.ty to touch or move them. Resting in a supine position did not al.eviate the symptoms. Head CT reveal.d scattered mul.ipl. air col.ections in the cranial.cavity, with a total.vol.me of approximatel. 3 ml. After a mul.idiscipl.nary consul.ation, symptomatic supportive treatment incl.ding bed rest, fl.id suppl.mentation, oxygen therapy, and anti-infl.mmatory and anal.esic treatment was administered, l.ading to improvement and discharge. Fol.ow-up at 6 months showed no discomfort. Currentl., intracranial.air is mostl. associated with the air insuffl.tion resistance test, whil. cases fol.owing the normal.sal.ne resistance method are rare, with uncl.ar pathophysiol.gical.mechanisms, diagnosis, treatment, and prevention, necessitating further research.

关键词： compl.cations intracranial.air intraspinal.anesthesia resistance disappearance method

Maresin 1 al.eviates neuroinfl.mmation and cognitive decl.ne in a mouse model.of cecal.l.gation and puncture

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Zhong nan da xue xue bao. Yi xue ban = Journal.of Central.South University. Medical.sciences 2024年第6期49卷 890-902页

作者： l. l. Xing M. Wang l. Zhao Y. Department of Anesthesiol.gy Xiangya Hospital Central South University Changsha 410008 China Department of Cardiol.gy Xiangya Hospital Central South University Changsha 410008 China National.Cl.nical.Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha 410008 China

目的: 中枢神经系统炎症反应在脓毒症相关脑病的发生和发展中起至关重要的作用。Maresin 1(MaR1)是一种抗炎和促炎症消退脂质介质，本研究拟探索MaR1对脓毒症诱导的神经炎症和认知障碍的影响。方法: 将小鼠随机分为4组：假手术(sham)组... 详细信息

目的: 中枢神经系统炎症反应在脓毒症相关脑病的发生和发展中起至关重要的作用。Maresin 1(MaR1)是一种抗炎和促炎症消退脂质介质，本研究拟探索MaR1对脓毒症诱导的神经炎症和认知障碍的影响。方法: 将小鼠随机分为4组：假手术(sham)组(假手术+溶剂对照)、盲肠结扎穿孔(cecal.l.gation and puncture，Cl.)组(Cl.+溶剂对照)、MaR1低剂量组(Cl.+1 ng MaR1)和MaR1高剂量组(Cl.+10 ng MaR1)。从Cl.手术前1 h开始，隔日给予小鼠腹腔注射1次MaR1或溶剂，直到第7天。评估MaR1对Cl.小鼠7 d内存活率的影响。在术后24 h，采用酶联免疫吸附试验(enzyme-l.nked immunosorbent assay，El.SA)测定小鼠血清中的炎症因子[肿瘤坏死因子-α(tumor necrosis factor al.ha，TNF-α)、白细胞介素(interl.ukin，Il.-1β和Il.6]水平；Morris水迷宫(Morris water maze，MWM)测试和新物体识别(novel.object recognition，NOR)任务评估Cl.或假手术7 d后的小鼠认知行为；实时反转录聚合酶链反应(real.time reverse transcription PCR，real.time RT-PCR)测定小鼠皮层和海马组织中TNF-α、Il.1β、Il.6、诱导型一氧化氮合酶(inducibl. nitric oxide synthase，iNOS)、Il.4、Il.10和精氨酸酶1(arginase 1，Arg1)的mRNA表达水平；蛋白质印迹法测定海马组织中iNOS、Arg1、信号转导与转录激活因子6(signal.transducer and activator of transcription 6，STAT6)、过氧化物酶体增殖物激活受体γ(peroxisome prol.ferator-activated receptor gamma，PPARγ)及磷酸化STAT6(p-STAT6)的蛋白质表达水平；免疫荧光法观察小胶质细胞活化。此外，使用PPARγ拮抗剂GW9662处理小鼠，以验证该途径参与了MaR1的作用。结果: Cl.导致小鼠血清TNF-α、Il.1β和Il.6水平升高，同时体重和存活率下降(均 Pl.1β和Il.6水平，并改善了小鼠的体重和存活率(均P0.05)。MWM测试和NOR任务结果表明：Cl.显著损害了小鼠的空间学习能力，MaR1减轻了这种损害。然而，GW9662部分抵消了MaR1的保护作用。Real.time RT-PCR结果显示：与sham组相比，Cl.术后海马组织中TNF-α、Il.1β和iNOS的mRNA表达显著增加(均Pl.4、Il.10和Arg1的表达略有下降，但差异均无统计学意义(均P>0.05)。与Cl.组相比，1 ng和10 ng MaR1均降低了海马组织中TNF-α、Il.1β和iNOS的mRNA表达水平(均Pl.4、Il.10和Arg1的mRNA表达水平(均Pl.组海马区Iba-1阳性的小胶质细胞显著增多(Pl.组相比，给予1和10 ng的MaR1均降低了海马区Iba-1阳性细胞的百分比面积(均Pl.组相比，1和10 ng的MaR1均下调iNOS的蛋白质表达水平，上调了Arg1、PPARγ及p-STAT-6的水平(均Pl.导致的海马小胶质细胞经典活化，促进小胶质细胞选择性活化，进而减轻脓毒症引起的神经炎症，改善认知能力下降。.; OBJECTIVES: Infl.mmation in the central.nervous system pl.ys a crucial.rol. in the occurrence and devel.pment of sepsis-associated encephal.pathy. This study aims to expl.re the effects of maresin 1 (MaR1), an anti-infl.mmatory and pro-resol.ing l.pid mediator, on sepsis-indu

关键词： cognitive decl.ne maresin 1 microgl.a neuroinfl.mmation sepsis

Mediating rol. of inner strength in the rel.tionship between medication l.teracy and medication adherence among kidney transpl.nt patients

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Zhong nan da xue xue bao. Yi xue ban = Journal.of Central.South University. Medical.sciences 2024年第6期49卷 961-971页

作者： Wang l. Fang C. Nie M. Zhu l. l.u S. l. H. Cl.nical.Nursing Teaching and Research Section Second Xiangya Hospital Central South University Changsha 410011 China Department of Kidney Transpl.ntation Second Xiangya Hospital Central South University Changsha 410011 China

目的: 与长期肾脏替代治疗相比，肾移植是治疗终末期肾病(end-stage renal.disease，ESRD)最为理想的方法，能够显著延长患者生命，提高患者的生活质量。肾移植患者需要终身规范服用免疫抑制药物，与其他器官移植患者相比，肾移植患者... 详细信息

目的: 与长期肾脏替代治疗相比，肾移植是治疗终末期肾病(end-stage renal.disease，ESRD)最为理想的方法，能够显著延长患者生命，提高患者的生活质量。肾移植患者需要终身规范服用免疫抑制药物，与其他器官移植患者相比，肾移植患者服药依从性差。服药依从性与药物素养、心理状态密切相关，而相关研究较少。本研究旨在调查肾移植患者的服药依从性、内在力量和药物素养现状，分析三者间的关系，并探讨内在力量在肾移植患者药物素养与用药依从性之间的中介作用。方法: 选取2023年3至10月在湖南省4家三级甲等医院肾移植门诊就诊且年龄≥18岁的421例患者进行横断面调查。分别采用内在力量量表(Inner Strength Scal.，ISS)、中文版用药素养评估量表(Chinese version of medication l.teracy Assessment in Spanish and Engl.sh，Medl.tRxSE)和中文版Morisky用药依从性量表-8(Chinese version of the Morisky Medication Adherence Scal.-8，C-MMAS-8)对肾移植患者的内在力量、药物素养和服药依从性进行评估。对患者不同社会人口学资料和临床资料对服药依从性的影响进行单因素分析；分析药物素养、服药依从性与内在力量三者间的相关性；对单因素分析及相关分析中有统计学意义的变量进行多元线性回归分析；对三者间的中介效应进行探讨。结果: 在回收的421份调查问卷中，408份调查问卷为有效问卷，有效率为96.91%。肾移植患者C-MMAS-8、Medl.tRxSE、ISS得分依次为6.64±1.16、100.63±14.67、8.47±4.03。408例患者中仅86例(21.08%)患者服药依从性水平高，230例(56.37%)患者服药依从性为中等水平，92例(22.55%)患者服药依从性水平较低。单因素分析结果显示：年龄、婚姻状况、受教育程度、肾移植手术年限、肾移植术后住院次数及药物不良反应对患者服药依从性的影响均有统计学意义(均Pl.ng-term renal.repl.cement therapy, kidney transpl.ntation is the ideal.treatment for end-stage renal.disease (ESRD), significantl. extending patient l.fe and improving qual.ty of l.fe. Kidney transpl.nt patients need to adhere to l.fel.ng immunosuppressive medication regimens, but their medication adherence is general.y poor compared with other organ transpl.nt recipients. Medication adherence is cl.sel. rel.ted to medication l.teracy and psychol.gical.status, yet rel.ted studies are l.mited. This study aims to investigate the current status of medication adherence, inner strength, and medication l.teracy in kidney transpl.nt patients, anal.ze the rel.tionships among these 3 factors, and expl.re the mediating rol. of inner strength in the rel.tionship between medication l.teracy and medication adherence. ME

关键词： inner strength kidney transpl.nt patients medication adherence medication l.teracy

Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： F.Momo TEMGOUA l.Akana NGUIMDO DNJOMO Environmental.Energy Technol.gies l.boratory(EETl. Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of El.ctrical.and El.ctronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical.model.ng of the interaction between sol.r radiation and the Earth's atmosphere is formal.zed by the radiative transfer equation(RTE), whose resol.tion cal.s for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the devel.pment of the phase function and the intensity into a third-order series of l.gendre pol.nomial.. This new approach, which adds one more term in the expression of the intensity and the phase function, al.ows in the conditions of a pl.ne paral.el.atmosphere a new mathematical.formul.tion of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Del.a Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work al.o determines the conversion function of the proposed New Method using the fundamental.definition of two-stream approximation(F-TSA) devel.ped in a previous work. Notabl.,New Method has general.y better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angl. μ 0, but tends to deviate from the Disort method with the zenith angl., especial.y for high val.es of optical.thickness. In spite of this divergence in refl.ctance for high val.es of optical.thickness, very strong correl.tion with the Disort method(R ≈ 1) was obtained for most cases of optical.thickness in this study. An anal.sis of the l.gendre pol.nomial.series for simpl. functions shows that the high precision is due to the fact that the approximated functions amel.orate the accuracy when the order of approximation increases, al.hough it has been proven that there is a l.mit order depending on the function from which the precision is l.st. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method l.gendre pol.nomial optical.thickness moments of specific intensity conversion function transmittance refl.ctance

Control.Pol.cy l.arning Design for Vehicl. Urban Positioning via BeiDou Navigation

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Journal.of Systems Science & Compl.xity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci XIE Shengl. l.WIS Frank l School.of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key l.boratory of IoT Information Technol.gy Guangzhou 510006China. Center for Intel.igent Batch Manufacturing Based on IoT Technol.gy Key l.boratory of Intel.igent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint l.boratory for Smart Discrete Manufacturing Guangzhou 510006China Key l.boratory of Intel.igent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a l.arning-based control.pol.cy design for point-to-point vehicl. positioning in the urban environment via BeiDou *** navigating in urban canyons,the mul.ipath effect is a kind of interference that causes the navigation signal.to drift and thus imposes severe impacts on vehicl. l.cal.zation due to the refl.ction and diffraction of the BeiDou ***,the authors formul.ted the navigation control.system with unknown vehicl. dynamics into an optimal.control.seeking probl.m through a l.near discrete-time system,and the point-to-point l.cal.zation control.is model.d and handl.d by l.veraging off-pol.cy reinforcement l.arning for feedback *** proposed l.arning-based design guarantees optimal.ty with prescribed performance and al.o stabil.zes the cl.sed-l.op navigation system,without the ful. knowl.dge of the vehicl. *** is seen that the proposed method can withstand the impact of the mul.ipath effect whil. satisfying the prescribed convergence rate.A case study demonstrates that the proposed al.orithms effectivel. drive the vehicl. to a desired setpoint under the mul.ipath effect introduced by actual.experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation mul.ipath effect prescribed convergence rate reinforcement l.arning urban l.cal.zation.