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1Latest Papers from Table of Contents or Articles in PressC. B. Hinke ; M. Bohmer ; P. Boutachkov ; T. Faestermann ; H. Geissel ; J. Gerl ; R. Gernhauser ; M. Gorska ; A. Gottardo ; H. Grawe ; J. L. Grebosz ; R. Krucken ; N. Kurz ; Z. Liu ; L. Maier ; F. Nowacki ; S. Pietri ; Z. Podolyak ; K. Sieja ; K. Steiger ; K. Straub ; H. Weick ; H. J. Wollersheim ; P. J. Woods ; N. Al-Dahan ; N. Alkhomashi ; A. Atac ; A. Blazhev ; N. F. Braun ; I. T. Celikovic ; T. Davinson ; I. Dillmann ; C. Domingo-Pardo ; P. C. Doornenbal ; G. de France ; G. F. Farrelly ; F. Farinon ; N. Goel ; T. C. Habermann ; R. Hoischen ; R. Janik ; M. Karny ; A. Kaskas ; I. M. Kojouharov ; T. Kroll ; Y. Litvinov ; S. Myalski ; F. Nebel ; S. Nishimura ; C. Nociforo ; J. Nyberg ; A. R. Parikh ; A. Prochazka ; P. H. Regan ; C. Rigollet ; H. Schaffner ; C. Scheidenberger ; S. Schwertel ; P. A. Soderstrom ; S. J. Steer ; A. Stolz ; P. Strmen
Nature Publishing Group (NPG)
Published 2012Staff ViewPublication Date: 2012-06-23Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 1089-7666Source: AIP Digital ArchiveTopics: PhysicsNotes: The stability of the axisymmetric Burgers vortex solution of the Navier–Stokes equations to two-dimensional perturbations is studied numerically up to Reynolds numbers, R=Γ/2πν, of order 104. No unstable eigenmodes for azimuthal mode numbers n=1,..., 10 are found in this range of Reynolds numbers. Increasing the Reynolds number has a stabilizing effect on the vortex. © 1995 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1432-1106Keywords: Neuromuscular ; Reflexes ; GaitSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary If an obstacle impedes the forward swing of a cat's foot, the animal responds by rapidly lifting the foot over the obstacle. In freely moving cats, the electrical activity of hindlimb flexors and extensors was recorded during such reactions elicited both mechanically and electrically. The sequencing of muscle activity was more complex and longer in duration in the mechanically elicited reactions. Anaesthesia of the foot dorsum abolished responses in ankle extensors and knee flexors, and converted the responses of ankle flexors to simple stretch reflexes. Although our findings closely resemble those reported for chronic spinal kittens, there are interesting points of difference, which should be taken into account if the notion of a purely spinal mediation of the placing reaction during stepping is to be accepted.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 1432-1106Keywords: Fusimotor neurones ; Muscle spindleSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary 1. The ability of single dynamic fusimotor (γd) fibres to sustain the firing of muscle spindle primary (Ia) afferents during shortening was investigated in soleus muscles of anaesthetised cats. 2. Of 11 γd fibres, 10 could maintain Ia firing during 10 mm/s shortening. Of the 7 tested at greater velocities, 5 could maintain Ia firing during shortening at velocities greater than 50 mm/s. 3. This ability was, however, critically dependent upon the timing of the stimulation. In particular, it rapidly reduced with increasing duration of stimulation before the onset of shortening. Furthermore, if appreciable stretch occurred between the onset of γd stimulation and the onset of shortening, this could greatly reduce the ability of γd fibres to sustain Ia discharge. 4. If γd neurones are on occasion phasically activated during voluntary shortening movements, their action could be an important determinant of Ia firing, even in the presence of weak γs action. Therefore in chronic recordings, observation of Ia firing during muscle shortening is not an adequate criterion for inferring γd activity.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 1432-1106Keywords: H-reflex ; Muscle spindle ; Locomotion ; HumanSource: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Summary Hoffmann (H) reflexes were elicited from the soleus (SOL) muscle while subjects walked on a treadmill and on a narrow beam (3.5 cm wide, raised 34 cm from the floor). The speed of walking on the treadmill was selected for each subject to match the background activation level of their SOL muscle during beam walking. The normal reciprocal activation pattern of the tibialis anterior and SOL muscles in treadmill walking was replaced by a pattern dominated by co-contraction on the beam. In addition, the step cycle duration was more variable and the time spent in the swing phase was reduced on the beam. The H-reflexes were highly modulated in both tasks, the amplitude being high in the stance phase and low in the swing phase. The H-reflex amplitude was on average 40% lower during beam walking than treadmill walking. The relationship between the H-reflex amplitude and the SOL EMG level was quantified by a regression line relating the two variables. The slope of this line was on average 41% lower in beam walking than treadmill walking. The lower H-reflex gain observed in this study and the high level of fusimotor drive observed in cats performing similar tasks suggest that the two mechanisms which control the excitability of this reflex pathway (i.e. fusimotor action and control of transmission at the muscle spindle to motoneuron synapse) may be controlled independently.Type of Medium: Electronic ResourceURL: