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Electro-anatomic mapping of the right atrium:anatomic abnormality is an important substrate

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Chinese Medical Journal 2003年第3期116卷 22-26页

作者：方丕华 Nancy L Radtke Tony W Simmons Wesley K Haisty Jr Karthik Ramaswamy David M.Fitzgerald Department of Cardiology Fuwai HospitalChinese Academy of Medical SciencesBeijing 100037China wake forest university School of Medicine Winston-Salem North Carolina 27157 USA

Objective To map and compare the right atrium in patients with AF to those with atrioventricular nodal reentrant tachycardias (AVNRT, as control group) and to investigate the anatomical and electrophysiological abnormality of the right atrium in *** The anatomy and electrophysiology of right atrium and cavotricuspid isthmus were evaluated in 20 patients with AF (16 M/4 F, mean age 55.9±10.68 years) and 26 patients with AVNRT (9 M/17 F, mean age 47.50±19.56 years) during coronary sinus pacing at 600 ms prior to ablation with electro-anatomical mapping system. Right atrial volume (RAV), the length and width of cavotricuspid isthmus (IsL, IsW), unipolar and bipolar voltage in the right atrium (univ-RA, BiV-RA) were measured and compared between patients with AF and those with AVNRT. Results RAV, IsL, IsW, univ-RA, and BiV-RA were 143.22±40.72 vs 104.35±21.06 ml, 39.31±8.10 vs 32.42±9.77 mm, 30.54±7.48 vs 23.15±6.61 mm, 1.96±1.24 vs 1.53±0.91 mv and 1.47±1.47 vs 1.29±1.12 mv in AF and AVNRT *** The right atrial volume is larger; both the length and width of cavotricuspid isthmus are greater. Unipolar and bipolar voltages in the right atrium are higher in AF than in AVNRT, suggesting that the enlarged right atrium, increased length and width of cavotricuspid isthmus, and concomitant atrial hypertrophy are important substrates for initiation and perpetuation of typical AF.

关键词： atrial flutter right atrium electrophysiology

NUMERICAL　STUDY　ON　THE　VORTEX　STRUCTURES　IN　THE　wake　OF　AN　OSCILLATING　CIRCULAR　CYLINDER　IN　A　UNIFORM　FLOW

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Journal of Hydrodynamics 1994年第1期6卷 12-22页

作者： Lu Xi-yun Tong Bing-gang Zhuang Li-xian Yin Xie-yuan (Department of Modern Mechanics, university of Science and Technology of China, Hefei, Anhui 230026,P. R. China) univ of Science and Technology of China Hefei China

Vortex shedding from a circular cylinder subjected to fortal oscillations at arbitrary angles(as shown in Fis. 1 for 0°<β<90°) with respect to the free stream is numerically investigated using the Navier-Stokes equ... 详细信息

Vortex shedding from a circular cylinder subjected to fortal oscillations at arbitrary angles(as shown in Fis. 1 for 0°wake. In the present study, a number of possible vortex modes are also numerically simulated, and a variety of physical phenomena are duplicated and even renewed numerically. A parameter map indicating the classification of preferred vortex modes is firstly given in the frequency-amplitude plane.

关键词： unsteady flow vortex motion separated flow oscillatory flow.

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皮肌炎自然缓解1例

世界核心医学期刊文摘（皮肤病学分册） 2005年第1期1卷 52-52页

作者： Jordan J.R. Paruthi S. Pichardo R.O. J.L.Jorizzo 崔荣 Center fo Dermatology Research Department of DermatologyWake Forest Univ.School of MedicineMedicalCenter BoulevardWinston-SalemNC 27157-1071United States

Dermatomyositis (DM) is an inflammatory myopathy of skeletal muscle with characteristic cutaneous *** is a rare disorder with a bimodal age distribution that affects almost twice as many women as *** category of DM, normal-enzyme DM, is characterized by cutaneous changes only at baseline, normal serum muscle enzyme levels and myositis demonstrated by electromyography (EMG) and/or muscle biopsy ***, patients with normal-enzyme DM progress to severe muscle involvement and require systemic corticosteroid *** patient we report has normal-enzyme DM confirmed by serial serum enzymes, EMG, and skin and muscle biopsies but is unique in that she never experienced progression of muscle weakness although muscle involvement was documented histologically and by ***-up examination after 1 year revealed near-complete resolution of cutaneous involvement after topical therapy and no evidence of muscle weakness.

关键词：皮肌炎感染性肌病正常性肌肉活检血清肌酶肌无力女性发病率皮质类固醇年龄分布

REMOTE SENSING METHODS FOR SHIP wake DETECTION IN SAR IMAGE

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Journal of Hydrodynamics 2001年第3期13卷 122-126页

作者： Meng, Jun-Min Tao, Ming-De Zhang, Jie Ocean univ. of Qingdao Qingdao 266003 China

The remote sensing methods for ship wake detection in SAR image is studied. The detection method for Kelvin ship wake is given by the research of SAR imaging of ship wake. The most oppcared ship wake is turbulent wake... 详细信息

关键词： Radar imaging Remote sensing Ships Synthetic aperture radar Velocity measurement

Direct Numerical Simulation of Particle Dispersion in the Flow Around a Circular Cylinder

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Journal of Thermal Science 2004年第4期13卷 344-349页

作者： Lan Liu Feng Ji Jianren Fan Kefa Cen Inst. of Thermal Power Eng. Zhejiang Univ. Hangzhou 310027 China

The major objective of the paper is to use direct numerical simulation method to get the dispersion patterns of different Stokes number particles in cylinder wake at low Reynolds numbers. The gas fluid structure is simulated by a spectral-element method with third-order accuracy. Non-reflecting boundary condition is specified for the outlet downstream boundary. Lagrangian approach is used to trace particle trajectory. The simulation results show factors to be considered to characterize the particle dispersion and find different particle dispersion pattern in a circular cylinder wake and in a plane wake.

关键词： direct numerical simulation wake particle dispersion gas-solid fluid.

Impact of wake on Downstream Adjacent Rotor in Low-speed Axial Compressor

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Journal of Thermal Science 2004年第2期13卷 114-120页

作者： Xinqian Zheng Sheng Zhou Beijing univ Aeronaut & Astronaut Sch Jet Prop Beijing 100083 Peoples R China

This paper investigates the effect of upstream wake on unsteady separated flow field of downstream adjacent vanes by solving 2D unsteady Reynolds-averaged Navier-Stokes equations discretized by a high-order scheme. The results indicated that the maximum relative reduction of loss coefficient was 27.2% when the relative passing frequency (the ratio of wake passing frequency to the characteristic frequency of trailing-vortex shedding of downstream adjacent rotor) is less than 2.5. The amplitude of wake defect exists a threshold value and the aerodynamic performance is enhanced monotonically with the amplitude of wake defect basically. The effective range of incidence must be greater than 8°, which is near the stall boundary.

关键词： unsteady flow separated flow rotor/stator interaction axial flow compressor.

wake structures of two spheres in tandem arrangement at various gaps for Re=300

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Progress in Natural Science:Materials International 2005年第2期15卷 37-41页

作者： ZOU Jianfeng*, REN Anlu, DENG Jian and CHEN Wenqu(Department of Mechanics, Zhejiang university, Hangzhou 310027, China) Dept. of Mechanics Zhejiang Univ. Hangzhou 310027 China

The virtual boundary method is extended to a 3D application and used to simulate the flow field of two spheres in tandem arrangement for a Reynolds number of 300. The wake structures and flow spectra at various gaps are investigated. The numerical results show that for small gaps (≈1.5), due to the mutual suppress between the wakes of the two spheres, the full flow field is stable and axisymmetric. As the gap is increased to 2.0, an asymmetric but stable flow is constructed through a certain bifurcation. The downstream wake structure is characterized by a double-thread vortex structure that comprises two slender parallel vortex tubes. The double-thread structure has a planar symmetry at gap 2.0. The hairpin-shape vortices are periodically shed from the downstream sphere at gap 2.5, but the planar symmetry persists. The vortex structures at gaps ranging from 3.0 to 4.0 are irregular and the flow field is undergoing a kind of 3D transition. It is up to the large gap 5.0 that the hairpin-shape structures are reconstructed behind the upstream and the downstream sphere, and the planar symmetry is resumed. All these numerical computations were performed on an SGI Origin3900 machine at the Center for Engineering and Scientific Computation of Zhejiang university.

关键词： virtual boundary method flow past two spheres wake structure flow spectra

Frequency Analyses for Mechanism Research of Unsteady Flow Inside Three Dimensional Compressor Cascade

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Journal of Thermal Science 2004年第3期13卷 207-212页

作者： Sheng Zhou Hongbin Wu Xinqian Zheng Beijing univ Aeronaut & Astronaut Natl Key Lab Aircraft Engine Beijing 100083 Peoples R China

Numerical simulations are carried out for unsteady flow field of certain kind of 3D compressor cascade. Emphasis is laid on vortex shedding and frequency analysis in a compressor cascade. Numerical simulations using unsteady Reynolds-averaged viscous turbulent equations are carried out. The results show that the flows in separated areas and wake areas are characterized as periodic or quasi-periodic vortex shedding and the frequencies of vortex shedding vary with incidences and Mach number. At the same Mach number, the frequency of vortex shedding will decrease as the incidence increases. Yet, the frequency will increase as the Mach number increases at the same incidence. In the same computation case, the frequency of vortex shedding will vary along the span of blade. The frequency is smaller at the middle of the span than that at the hub.

关键词： axial flow compressor cascade unsteady flow separated flow frequency of vortex shedding.

Sleep and Subjective Recovery in Amateur Trail Runners After the Ultra-Trail du Mont Blanc^(®)(UTMB^(®))

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Journal of Science in Sport and Exercise 2023年第2期5卷 123-129页

作者： Pauline Baron Éric Hermand Charlotte Elsworth‑Edelsten Thierry Pezé Valentin Bourlois Benoit Mauvieux Rémy Hurdiel univ.Lille Univ.ArtoisUniv.Littoral Côte d’OpaleULR 7369-URePSSS-Unitéde Recherche Pluridisciplinaire Sport SantéSociétéF‑59000 LilleFrance School of Human and Life Sciences Canterbury Christ Church UniversityCanterburyKentUK COMETE GIP CYCERONINSERMNormandie UnivUNICAEN14000 CaenFrance

Purpose The interaction between sleep and recovery is a fundamental issue for ultra-marathoners,especially after an ultra-trail,but literatures on this matter remains are *** main objectives were(1)to describe sleep parameters during the nights following an ultra-endurance event in amateur trail runners,(2)to evaluate the recovery kinetics,and(3)to assess the relationship between sleep parameters and *** Nineteen race finishers were tested daily,from 10 days before to 10 days after the Ultra-Trail du Mont-Blanc^(®)(UTMB^(®)).Hooper Index(HI)was used to assess recovery and sleep parameters(total sleep time,TST and wake after sleep onset,WASO)were monitored using a wrist-worn *** HI was higher than baseline until day 5 after the race(P<0.05)and younger athletes had a lower HI than older ones during the recovery period(P<0.001).TST was not modified by the race,but there was a WASO peak on the second night *** correlations were found between WASO and muscle soreness(P<0.001)and between TST and HI(P<0.05).Conclusions In conclusion,participants needed 6 days for recovery after UTMB^(®)and younger runners seemed to recover faster than older ***-race sleep quantity did not increase,but the second night was more fragmented,most likely due to muscle *** between sleep and recovery parameters highlighted the key role of sleep for recovery.

关键词： Ultra endurance Sleep deprivation Hooper Index Exercise