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Journal of Otology 2021年第3期16卷 199-204页

作者： Allison Nogi Michael C.schubert Department of Physical Medicine and Rehabilitation Johns Hopkins University School of MedicineBaltimoreMDUSA Laboratory of Vestibular NeuroAdaptation Department of Otolaryngology-Head and Neck SurgeryJohns Hopkins School of MedicineBaltimoreMDUSA

A 73-year-old female presented to the emergency department with chief complaint of dizziness after sustaining a fall one month prior to dizziness *** careful examination of eye movement patterns during positional testing was attempted at varying stages of her inpatient admission,her complex nystagmus patterns as a result of traumatic benign paroxysmal vertigo were difficult to *** particular,the nystagmus pattern from this case suggests the BPPV was variable and affecting either 1)left posterior semicircular canal(pSCC)exclusively 2)left pSCC and right anterior semicircular canal,3)left and right pSCC *** case illustrates the importance of two critical details;positional testing should include observing nystagmus with fixation removed and an experienced clinician should be involved as early as possible.

关键词： vertigo critical semicircular

The effect of the equatorially symmetric zonal winds of Saturn on its gravitational field

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Research in Astronomy and Astrophysics 2018年第4期18卷 15-22页

作者： Dali Kong Keke Zhang Gerald schubert John D.Anderson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and Planetary Science Laboratory Macao University of Science and Technology Macao China Department of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The penetration depth of Saturn’s cloud-level winds into its interior is unknown.A possible way of estimating the depth is through measurement of the effect of the winds on the planet’s gravitational *** use a self-consistent perturbation approach to study how the equatorially symmetric zonal winds of Saturn contribute to its gravitational *** important advantage of this approach is that the variation of its gravitational field solely caused by the winds can be isolated and identified because the leading-order problem accounts exactly for rotational distortion,thereby determining the irregular shape and internal structure of the hydrostatic *** assume that（i）the zonal winds are maintained by thermal convection in the form of non-axisymmetric columnar rolls and（ii）the internal structure of the winds,because of the Taylor-Proundman theorem,can be uniquely determined by the observed cloud-level *** calculate both the variation △J_n,n=2,4,6...of the axisymmetric gravitational coefficients J_n caused by the zonal winds and the non-axisymmetric gravitational coefficients △J_（nm） produced by the columnar rolls,where m is the azimuthal wavenumber of the *** consider three different cases characterized by the penetration depth 0.36 R_S,0.2 R_S and 0.1 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure *** find that the high-degree gravitational coefficient （ J_（12）＋△J_（12）） is dominated,in all the three cases,by the effect of the zonal flow with ｜△J_（12）/J_（12）｜〉100%and that the size of the non-axisymmetric coefficientsdirectly reflects the depth and scale of the flow taking place in the Saturnian interior.

关键词： gravitation — planets and satellites individual(Saturn) — planets and satellites interiors

A model of Saturn inferred from its measured gravitational field

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Research in Astronomy and Astrophysics 2018年第4期18卷 7-14页

作者： Dali Kong Keke Zhang Gerald schubert John D.Anderson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and Planetary Science Laboratory Macao University of Science and Technology Macao China Department of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

We present an interior model of Saturn with an ice-rock core,a metallic region,an outer molecular envelope and a thin transition layer between the metallic and molecular *** shape of Saturn’s 1 bar surface is irregular and determined fully self-consistently by the required equilibrium *** the ice-rock core is assumed to have a uniform density,three different equations of state are adopted for the metallic,molecular and transition *** Saturnian model is constrained by its known mass,its known equatorial and polar radii,and its known zonal gravitational coefficients,J_（2n）,n=1,2,*** model produces an ice-rock core with equatorial radius 0.203 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure surface;the core densityρ_c=10388.1 kgm^（3）corresponding to 13.06 Earth masses;and an analytical expression describing the Saturnian irregular shape of the 1-bar pressure *** model also predicts the values of the higher-order gravitational coefficients,J_8,J_10 and J_12,for the hydrostatic Saturn and suggests that Saturn’s convective dynamo operates in the metallic region approximately defined by 0.2 R_S

关键词： gravitation — planets and satellites individual(Saturn) — planets and satellites interiors

Saturn＇s gravitational field induced by its equatorially antisymmetric zonal winds

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Research in Astronomy and Astrophysics 2018年第5期18卷 29-36页

作者： Dali Kong Keke Zhang Gerald schubert John D.Anderson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and Planetary Science Laboratory Macao University of Science and Technology Macao China Department of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The cloud-level zonal winds of Saturn are marked by a substantial equatorially antisymmetric component with a speed of about 50 m s^-1 which, if they are sufficiently deep, can produce measurable odd zonal gravitational coefficients △J2 k＋1, k = 1, 2, 3, 4. This study, based on solutions of the thermal-gravitational wind equation, provides a theoretical basis for interpreting the odd gravitational coefficients of Saturn in terms of its equatorially antisymmetric zonal flow. We adopt a Saturnian model comprising an ice-rock core, a metallic dynamo region and an outer molecular envelope. We use an equatorially antisymmetric zonal flow that is parameterized, confined in the molecular envelope and satisfies the solvability condition required for the thermal-gravitational wind equation. The structure and amplitude of the zonal flow at the cloud level are chosen to be consistent with observations of *** calculate the odd zonal gravitational coefficients △J2k＋1, k = 1, 2, 3, 4 by regarding the depth of the equatorially antisymmetric winds as a parameter. It is found that △J3 is-4.197 × 10^-8 if the zonal winds extend about 13 000 km downward from the cloud tops while it is-0.765 × 10^-8 if the depth is about 4000 km. The depth/profile of the equatorially antisymmetric zonal winds can eventually be estimated when the high-precision measurements of the Cassini Grand Finale become available.

关键词： gravitation - planets and satellites individual (Saturn) - planets and satellites interiors

Preparation of nano-crystalline tungsten powders from gaseous WO_(2)(Oh)_(2)

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Tungsten 2022年第1期4卷 60-66页

作者： Markus Ostermann Valentin Dalbauer Wolf-Dieter schubert Roland haubner TU Wien A-1060 ViennaAustria

The industrial production of tungsten powder is carried out by the reduction of tungsten oxide powder via *** this process,the size of the W particles is limited to particle sizes larger than 100 *** get below this limit,alternative processes are *** the current work,the possibility of preparing W powder below 100 nm via a vapour phase reduction of volatile WO_(2)(Oh)_(2)by hydrogen was *** process consists of two *** the first stag,e WO_(2)(Oh)_(2)is formed by reacting WO3 with water vapour at temperatures of 1000–1100°*** the second stage,WO_(2)(Oh)_(2)is reduced by hydrogen at about 1000°C to form metallic *** influence of process parameters such as furnace temperature,humidity and gas flow on the WO_(2)(Oh)_(2)evaporation and formation of tungsten powder was *** characterization of the resulting powders was performed by X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM)and transmission electron microscopy(TEM).By optimization of the reaction conditions,powder with a metallic tungsten content of about 70 at%besides tungsten oxides was produced with metal particle sizes down to 5 *** optimization should lead to a high tungsten content and a high product *** to the small particle size,applications in catalysis might be possible,although an industrial realization of the process seems unrealistic at moment.

关键词： Tungsten Chemical vapour transport Mechanism·Reduction Nano-sized powder WO_(2)(Oh)_(2)

Structure-property relationships in ILs: A study of the alkyl chain length dependence in vaporisation enthalpies of pyridinium based ionic liquids

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Science China Chemistry 2012年第8期55卷 1525-1531,1-6页

作者： ZAITSAU Dzmitry h. YERMALAYEU Andrei V. EMEL'YANENKO Vladimir N. VEREVKIN Sergey P. WELZ-BIERMANN Urs schubert Thomas Department of Physical Chemistry University of Rostock Dr-Lorenz-Weg 1 D-18059 Rostock Germany Evonik Degussa Taiwan Ltd. 133 Minsheng East Road Section Taipei 10596 China 3IoLiTec Ionic Liquids Technologies GmbH Salzstrasse 184 74076 Heilbronn Germany

The enthalpies of vaporization for the series of pyridinium-based ionic liquids with bis（trifluoromethylsulfonyl）imide anion [CnPy][NTfz] （n = 2, 3, 4, 5, and 6） have been determined with the quartz crystal microbalance technique combined with the Langmuir evaporation. The linear dependence of vaporization enthalpies on the chain length has been revealed. New approach based on volumetric, surface tension, and speed of sound measurements has been developed for estimation of heat capacity differences between gas and liquid phase, which were required for adjustment of measured vaporization enthalpies to the ref- erence temperature 298 K.

关键词： ionic liquids enthalpy of vaporization quartz crystal microbalance structure-property relations

Expression of the human TSPY gene in the brains of transgenic mice suggests a potential role of this Y chromosome gene in neural functions

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Journal of Genetics and Genomics 2011年第5期38卷 181-191页

作者： Tatsuo Kido Stephanie schubert Jrg Schmidtke Yun-Fai Chris Lau Division of Cell and Developmental Genetics Department of MedicineVA Medical Centerand Institute for Human GeneticsUniversity of California Institute of human Genetics Hannover Medical School

The testis specific protein Y-encoded （TSPY） is a member of TSPY/SET/NAP1 superfamily, encoded within the gonadoblastoma locus on the Y chromosome. TSPY shares a highly conserved SET/NAP-domain responsible for protein--protein interaction among TSPY/SET/NAP 1 proteins. Accumulating data, so far, support the role of TSPYas the gonadoblastoma gene, involved in germ cell tumorigenesis. The X-chromosome homolog of TSPY, TSPX is expressed in various tissues at both fetal and adult stages, including the brain, and is capable of interacting with the multi-domain adapter protein CASK, thereby influencing the synaptic and transcriptional functions and developmental regulation of CASK in the brain and other neural tissues. Similar to TSPX, we demonstrated that TSPY could interact with CASK at its SET/NAP-domain in cultured cells. Transgenic mice harboring a human TSPYgene and flanking sequences showed specific expression of the human TSPYtransgene in both testis and brain. The neural expression pattern of the human TSPYgene overlapped with those of the endogenous mouse Cask and Tspx gene. Similarly with TSPX, TSPY was co-localized with CASK in neuronal axon fibers in the brain, suggesting a potential role（s） of TSPY in development and/or physiology of the nervous system.

关键词： TSPY TSPX CASK Y chromosome Neuron Testis

Measuring Scientific Productivity in China Using Malmquist Productivity Index

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Journal of Data and Information Science 2019年第1期4卷 32-59页

作者： Yaoyao Song Torben schubert huihui Liu Guoliang Yang Institutes of Science and Development Chinese Academy of Sciences University of Chinese Academy of Sciences Fraunhofer Institute for Systems and Innovation Research ISI Center for Innovation Research and Competence in the Learning Economy(CIRCLE)at Lund University

Purpose: This paper aims to investigate the scientific productivity of China's science system. Design/methodology/approach: This paper employs the Malmquist productivity index(MPI) based on Data Envelopment Analysis(DEA).Findings: The results reveal that the overall efficiency of Chinese universities increased significantly from 2009 to 2016, which is mainly driven by technological progress. From the perspective of the functions of higher education, research and transfer activities perform better than the teaching *** limitations: As an implication, the indicator selection mechanism, investigation period and the MPI model can be further extended in the future *** implications: The results indicate that Chinese education administrative departments should take actions to guide and promote the teaching activities and formulate reasonable resource allocation regulations to reach the balanced development in Chinese ***/value: This paper selects 58 Chinese universities and conducts a quantified measurement during the period 2009–2016. Three main functional activities of universities(i.e. teaching, researching, and application) are innovatively categorized into different schemes, and we calculate their performance, respectively.

关键词： Data Envelopment Analysis (DEA) Chinese higher education Scientific productivity Malmquist Productivity Index(MPI)

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhATIR T.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy

What every gastroenterologist needs to know about common anorectal disorders

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World Journal of Gastroenterology 2009年第26期15卷 3201-3209页

作者： Moonkyung Cho schubert Subbaramiah Sridhar Robert R Schade Steven D Wexner Department of Gastroenterology and hepatology Medical College of Georgia Department of Colorectal Surgery Cleveland Clinic Florida2950 Cleveland Clinic Boulevard

Anorectal complaints are very common and are caused by a variety of mostly benign anorectal *** anorectal conditions may be successfully treated by primary care physicians in the outpatient setting,but patients tend not to seek medical attention due to embarrassment or fear of *** a result,patients frequently present with advanced disease after experiencing significant decreases in quality of life.A number of patients with anorectal complaints are referred to ***,gastroenterologists' knowledge and experience in approaching these conditions may not be *** article can serve as a guide to gastroenterologists to recognize,evaluate,and manage medically or non-surgically common benign anorectal disorders,and to identify when surgical referrals are most prudent.A review of the current literature is performed to evaluate comprehensive clinical pearls and management guidelines for each *** reviewed include hemorrhoids,anal fissures,anorectal fistulas and abscesses,and pruritus ani.

关键词： Anal fissures Anorectal disease Anorectal fistulas and abscesses hemorrhoids Pruritus ani