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Science China Mathematics 1992年第1期35卷 81-90页

作者：魏中磊吴忠 h.e.fiedler Department of Mechnics Peking University Beijing 100871 PRC hermann-Fottinger Institut Technische Universitat Berlin 1000 Berlin 12

In this paper, some preliminary experiments of ordered and chaotic vortex sheddingsbehind a 2--D circular cylinder at Reynolds numbers ranging from R_e=50 to 400 are presented.A transition in vortex shedding from the laminar to chaotic state occurs at Re=184.6-193.5,but it is seemingly not through the quasi--periodicity routes. There is a couple of dis-continuities in slope on the curve of the relationship between the vortex shedding frequencyand Reynolds number. The discontinuity at Re = 70 might correspond to the change of themode of the oblique vortex shedding. The second one at Re = 193.5 is responsible for thetransition from the ordered to the chaotic state.

关键词： ordered and chaotic phenomena vortex shedding wake.

Ordered and chaotic phenomena of vortex shedding in an excited wake flow behind a 2-D oscillating circular cylinder

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Science China Mathematics 1995年第4期38卷 447-461页

作者：魏中磊张子强 h.e.fiedler Department of Mechanics Peking University Beijing 100871 China h-F Institute TU D-10623 Berlin Germany

The behavior of synchronization in an open flow dynamical system, especially in an excited wake flow behind a 2-D oscillating circular cylinder with Reynolds number Re ranging from 45 to 200 is presented. The experiment reveals that only under certain conditions can the competition between frequencies of oscillating cylinder and the vortex shedding in the wake flow result in 'window of chaos' with the mixed RTN and Feigenbaum scenario in the range of Re<185.

关键词： synchronization chaotic behavior wake vortex shedding oscillation.

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振荡圆柱尾流内旋涡脱落的有序和混沌现象

中国科学（A辑） 1994年第10期24卷 1065-1075页

作者：魏中磊张自强 h.e.fiedler 北京大学力学系北京100871 h.F.Intitute TU Berlin 1000 Berlin 12

研究了二维振荡圆柱后尾流内旋涡脱落的有序和混沌现象,实验Reynolds数的范围是Re=45-200。实验发现,当Re<180时,由于涡脱落的自然频率和圆柱强迫振荡频率之间的相互干涉,在通向混沌的途径上会形成“混沌窗口”。还揭示了在开放流体动... 详细信息

研究了二维振荡圆柱后尾流内旋涡脱落的有序和混沌现象,实验Reynolds数的范围是Re=45-200。实验发现,当Re<180时,由于涡脱落的自然频率和圆柱强迫振荡频率之间的相互干涉,在通向混沌的途径上会形成“混沌窗口”。还揭示了在开放流体动力学系统内(尾流)的同步锁频现象及其与混沌现象之间的某些联系和规律。

关键词：混沌尾流旋涡脱落有序湍流

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

Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

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Optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-ReKABI A.A.ALWAhIB electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 139-156页

作者： h.hOSSeINI O.BALILAShAKI Department of Mechanical engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： Stress concentration

DNA barcoding-based species delimitation increases species count of eois （Geometridae） moths in a well-studied tropical mountain forest by up to 50%

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Insect Science 2011年第3期18卷 349-362页

作者： Patrick Strutzenberger Gunnar Brehm Konrad fiedler Department of Animal Biodiversity University of Vienna Rennweg 14 1030 Wien Austria Institut for Spezielle Zoologie und evolutionsbiologie mit Phyletischem Museum Friedrich Schiller Universitat Erbertstrasse 1 07743 Jena Germany

The genus eois comprises an important part of megadiverse assemblages of geometrid moths in mountain rainforests of southern ecuador. In this study we report：（i） on the construction of a DNA barcode library of eois for identification purposes; and （ii） the exploration of species diversity through species delimitation by pair-wise distance thresholds. COl barcode sequences were generated from 408 individuals （at least 105 species） collected on a narrow geographic scale （-40 km2） in the Reserva Bioldgica San Francisco. Analyses of barcode sequence divergence showed that species delimitations based solely on external morphology result in broad overlap of intra- and interspecific distances. Species delimitation at a 2% pair-wise distance threshold reveals a clear barcoding gap. Fifty-two previously unrecognized species were identified, 31 of which could only be distinguished by an integrative taxonomy approach. Twelve additional putative species could only be recognized by threshold-based delimitation. Most splits resulted in two or three newly perceived cryptic taxa. The present study increased the number of eois species recorded from that small area of Andean mountain forest from 102 to 154 （morphology- plus integrative taxonomy-based） or even 166 （sequence-based）, leaving the species accumulation curve still far from reaching an asymptote. Notably, in no case did two or more previously distinguished morphospecies have to be lumped. This barcode inventory can be used to match larvae to known adult samples without rearing, and will therefore be of vital help to extend the currently limited knowledge about food plant relationships and host specialization.

关键词： cryptic species ecuador integrative taxonomy Larentiinae larvae