JN AJP: Lung Cellular and Molecular Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


J Neurophysiol 76: 492-509, 1996;
0022-3077/96 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (204)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bastian, A. J.
Right arrow Articles by Thach, W. T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bastian, A. J.
Right arrow Articles by Thach, W. T.

Journal of Neurophysiology, Vol 76, Issue 1 492-509, Copyright © 1996 by APS


ARTICLES

Cerebellar ataxia: abnormal control of interaction torques across multiple joints

A. J. Bastian, T. A. Martin, J. G. Keating and W. T. Thach
Department of Anatomy and Neurobiology, Irene Walter Johnson Institute of Rehabilitation Research, Washington University School of Medicine, St. Louis, Missouri 63110, USA.

1. We studied seven subjects with cerebellar lesions and seven control subjects as they made reaching movements in the sagittal plane to a target directly in front of them. Reaches were made under three different conditions: 1) "slow-accurate," 2) "fast-accurate," and 3) "fast as possible." All subjects were videotaped moving in a sagittal plane with markers on the index finger, wrist, elbow, and shoulder. Marker positions were digitized and then used to calculate joint angles. For each of the shoulder, elbow and wrist joints, inverse dynamics equations based on a three-segment limb model were used to estimate the net torque (sum of components) and each of the component torques. The component torques consisted of the torque due to gravity, the dynamic interaction torques induced passively by the movement of the adjacent joint, and the torque produced by the muscles and passive tissue elements (sometimes called "residual" torque). 2. A kinematic analysis of the movement trajectory and the change in joint angles showed that the reaches of subjects with cerebellar lesions were abnormal compared with reaches of control subjects. In both the slow-accurate and fast-accurate conditions the cerebellar subjects made abnormally curved wrist paths; the curvature was greater in the slow-accurate condition. During the slow-accurate condition, cerebellar subjects showed target undershoot and tended to move one joint at a time (decomposition). During the fast-accurate reaches, the cerebellar subjects showed target overshoot. Additionally, in the fast-accurate condition, cerebellar subjects moved the joints at abnormal rates relative to one another, but the movements were less decomposed. Only three subjects were tested in the fast as possible condition; this condition was analyzed only to determine maximal reaching speeds of subjects with cerebellar lesions. Cerebellar subjects moved more slowly than controls in all three conditions. 3. A kinetic analysis of torques generated at each joint during the slow-accurate reaches and the fast-accurate reaches revealed that subjects with cerebellar lesions produced very different torque profiles compared with control subjects. In the slow-accurate condition, the cerebellar subjects produced abnormal elbow muscle torques that prevented the normal elbow extension early in the reach. In the fast-accurate condition, the cerebellar subjects produced inappropriate levels of shoulder muscle torque and also produced elbow muscle torques that did not very appropriately with the dynamic interaction torques that occurred at the elbow. Lack of appropriate muscle torque resulted in excessive contributions of the dynamic interaction torque during the fast-accurate reaches. 4. The inability to produce muscle torques that predict, accommodate, and compensate for the dynamic interaction torques appears to be an important cause of the classic kinematic deficits shown by cerebellar subjects during attempted reaching. These kinematic deficits include incoordination of the shoulder and the elbow joints, a curved trajectory, and overshoot. In the fast-accurate condition, cerebellar subjects often made inappropriate muscle torques relative to the dynamic interaction torques. Because of this, interaction torques often determined the pattern of incoordination of the elbow and shoulder that produced the curved trajectory and target overshoot. In the slow-accurate condition, we reason that the cerebellar subjects may use a decomposition strategy so as to simplify the movement and not have to control both joints simultaneously. From these results, we suggest that a major role of the cerebellum is in generating muscle torques at a joint that will predict the interaction torques being generated by other moving joints and compensate for them as they occur.


This article has been cited by other articles:


Home page
J. Neurophysiol.Home page
Y.-K. Kim, R. N. Hinrichs, and N. Dounskaia
Multicomponent Control Strategy Underlying Production of Maximal Hand Velocity During Horizontal Arm Swing
J Neurophysiol, November 1, 2009; 102(5): 2889 - 2899.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
K. Rabe, O. Livne, E. R. Gizewski, V. Aurich, A. Beck, D. Timmann, and O. Donchin
Adaptation to Visuomotor Rotation and Force Field Perturbation Is Correlated to Different Brain Areas in Patients With Cerebellar Degeneration
J Neurophysiol, April 1, 2009; 101(4): 1961 - 1971.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
K. Rabe, B. Brandauer, Y. Li, E. R. Gizewski, D. Timmann, and J. Hermsdorfer
Size-Weight Illusion, Anticipation, and Adaptation of Fingertip Forces in Patients With Cerebellar Degeneration
J Neurophysiol, February 1, 2009; 101(2): 569 - 579.
[Abstract] [Full Text] [PDF]


Home page
Clin RehabilHome page
C. Martin, D. Tan, P. Bragge, and A. Bialocerkowski
Effectiveness of physiotherapy for adults with cerebellar dysfunction: a systematic review
Clinical Rehabilitation, January 1, 2009; 23(1): 15 - 26.
[Abstract] [PDF]


Home page
J. Neurophysiol.Home page
J. Bo, H. J. Block, J. E. Clark, and A. J. Bastian
A Cerebellar Deficit in Sensorimotor Prediction Explains Movement Timing Variability
J Neurophysiol, November 1, 2008; 100(5): 2825 - 2832.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
W. Ilg, M. A. Giese, E. R. Gizewski, B. Schoch, and D. Timmann
The influence of focal cerebellar lesions on the control and adaptation of gait
Brain, November 1, 2008; 131(11): 2913 - 2927.
[Abstract] [Full Text] [PDF]


Home page
J. Physiol.Home page
D. S. Soteropoulos and S. N. Baker
Bilateral representation in the deep cerebellar nuclei
J. Physiol., February 15, 2008; 586(4): 1117 - 1136.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
S. Y. Schaefer, K. Y. Haaland, and R. L. Sainburg
Ipsilesional motor deficits following stroke reflect hemispheric specializations for movement control
Brain, August 1, 2007; 130(8): 2146 - 2158.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
J. Diedrichsen, S. E. Criscimagna-Hemminger, and R. Shadmehr
Dissociating Timing and Coordination as Functions of the Cerebellum
J. Neurosci., June 6, 2007; 27(23): 6291 - 6301.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
J. Herzog, W. Hamel, R. Wenzelburger, M. Potter, M. O. Pinsker, J. Bartussek, A. Morsnowski, F. Steigerwald, G. Deuschl, and J. Volkmann
Kinematic analysis of thalamic versus subthalamic neurostimulation in postural and intention tremor
Brain, June 1, 2007; 130(6): 1608 - 1625.
[Abstract] [Full Text] [PDF]


Home page
ptjournalHome page
J. M Wagner, C. E Lang, S. A Sahrmann, D. F Edwards, and A. W Dromerick
Sensorimotor Impairments and Reaching Performance in Subjects With Poststroke Hemiparesis During the First Few Months of Recovery
Physical Therapy, June 1, 2007; 87(6): 751 - 765.
[Abstract] [Full Text] [PDF]


Home page
Mult SclerHome page
C. Solaro, G. Brichetto, M. Casadio, L. Roccatagliata, P. Ruggiu, G.L. Mancardi, P.G. Morasso, P. Tanganelli, and V. Sanguineti
Subtle upper limb impairment in asymptomatic multiple sclerosis subjects
Multiple Sclerosis, April 1, 2007; 13(3): 428 - 432.
[Abstract] [PDF]


Home page
J. Neurophysiol.Home page
M. Hirashima, K. Kudo, K. Watarai, and T. Ohtsuki
Control of 3D Limb Dynamics in Unconstrained Overarm Throws of Different Speeds Performed by Skilled Baseball Players
J Neurophysiol, January 1, 2007; 97(1): 680 - 691.
[Abstract] [Full Text] [PDF]


Home page
Neurorehabil Neural RepairHome page
C. E. Lang, J. M. Wagner, D. F. Edwards, S. A. Sahrmann, and A. W. Dromerick
Recovery of Grasp versus Reach in People with Hemiparesis Poststroke
Neurorehabil Neural Repair, December 1, 2006; 20(4): 444 - 454.
[Abstract] [PDF]


Home page
PediatricsHome page
T. D. Sanger, D. Chen, M. R. Delgado, D. Gaebler-Spira, M. Hallett, J. W. Mink, and the Taskforce on Childhood Motor Disorders
Definition and Classification of Negative Motor Signs in Childhood
Pediatrics, November 1, 2006; 118(5): 2159 - 2167.
[Abstract] [Full Text] [PDF]


Home page
Cereb CortexHome page
H. Chen, S. E. Hua, M. A. Smith, F. A. Lenz, and R. Shadmehr
Effects of Human Cerebellar Thalamus Disruption on Adaptive Control of Reaching
Cereb Cortex, October 1, 2006; 16(10): 1462 - 1473.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
A. d'Avella, A. Portone, L. Fernandez, and F. Lacquaniti
Control of fast-reaching movements by muscle synergy combinations.
J. Neurosci., July 26, 2006; 26(30): 7791 - 7810.
[Abstract] [Full Text] [PDF]


Home page
J Child NeurolHome page
T. D. Sanger
Arm Trajectories in Dyskinetic Cerebral Palsy Have Increased Random Variability
J Child Neurol, July 1, 2006; 21(7): 551 - 557.
[Abstract] [PDF]


Home page
J. Neurophysiol.Home page
D. E. Vaillancourt, M. A. Mayka, and D. M. Corcos
Intermittent Visuomotor Processing in the Human Cerebellum, Parietal Cortex, and Premotor Cortex
J Neurophysiol, February 1, 2006; 95(2): 922 - 931.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
C. R. Mason, C. M. Hendrix, and T. J. Ebner
Purkinje Cells Signal Hand Shape and Grasp Force During Reach-to-Grasp in the Monkey
J Neurophysiol, January 1, 2006; 95(1): 144 - 158.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
P. H. McCrea, J. J. Eng, and A. J. Hodgson
Saturated Muscle Activation Contributes to Compensatory Reaching Strategies After Stroke
J Neurophysiol, November 1, 2005; 94(5): 2999 - 3008.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
J. Konczak, B. Schoch, A. Dimitrova, E. Gizewski, and D. Timmann
Functional recovery of children and adolescents after cerebellar tumour resection
Brain, June 1, 2005; 128(6): 1428 - 1441.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
M. A. Smith and R. Shadmehr
Intact Ability to Learn Internal Models of Arm Dynamics in Huntington's Disease But Not Cerebellar Degeneration
J Neurophysiol, May 1, 2005; 93(5): 2809 - 2821.
[Abstract] [Full Text] [PDF]


Home page
NeurologyHome page
R. M. Bracewell, R. Balasubramaniam, and A. M. Wing
Interlimb coordination deficits during cyclic movements in cerebellar hemiataxia
Neurology, February 22, 2005; 64(4): 751 - 752.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
J. Diedrichsen, T. Verstynen, S. L. Lehman, and R. B. Ivry
Cerebellar Involvement in Anticipating the Consequences of Self-Produced Actions During Bimanual Movements
J Neurophysiol, February 1, 2005; 93(2): 801 - 812.
[Abstract] [Full Text] [PDF]


Home page
NeuroscientistHome page
S. M. Morton and A. J. Bastian
Cerebellar Control of Balance and Locomotion
Neuroscientist, June 1, 2004; 10(3): 247 - 259.
[Abstract] [PDF]


Home page
J. Neurophysiol.Home page
J. Monzee, T. Drew, and A. M. Smith
Effects of Muscimol Inactivation of the Cerebellar Nuclei on Precision Grip
J Neurophysiol, March 1, 2004; 91(3): 1240 - 1249.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
M. Maschke, C. M. Gomez, T. J. Ebner, and J. Konczak
Hereditary Cerebellar Ataxia Progressively Impairs Force Adaptation During Goal-Directed Arm Movements
J Neurophysiol, January 1, 2004; 91(1): 230 - 238.
[Abstract] [Full Text]


Home page
J. Neurophysiol.Home page
B. Greger, S. A. Norris, and W. T. Thach
Spike Firing in the Lateral Cerebellar Cortex Correlated With Movement and Motor Parameters Irrespective of the Effector Limb
J Neurophysiol, January 1, 2004; 91(1): 576 - 582.
[Abstract] [Full Text]


Home page
J. Neurophysiol.Home page
R. S. Turner, M. Desmurget, J. Grethe, M. D. Crutcher, and S. T. Grafton
Motor Subcircuits Mediating the Control of Movement Extent and Speed
J Neurophysiol, December 1, 2003; 90(6): 3958 - 3966.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
D. T. Stuss, K. J. Murphy, M. A. Binns, and M. P. Alexander
Staying on the job: the frontal lobes control individual performance variability
Brain, November 1, 2003; 126(11): 2363 - 2380.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
M. Hirashima, K. Ohgane, K. Kudo, K. Hase, and T. Ohtsuki
Counteractive Relationship Between the Interaction Torque and Muscle Torque at the Wrist Is Predestined in Ball-Throwing
J Neurophysiol, September 1, 2003; 90(3): 1449 - 1463.
[Abstract] [Full Text] [PDF]


Home page
ScienceHome page
R. M. C. Spencer, H. N. Zelaznik, J. Diedrichsen, and R. B. Ivry
Disrupted Timing of Discontinuous But Not Continuous Movements by Cerebellar Lesions
Science, May 30, 2003; 300(5624): 1437 - 1439.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
M. Hirashima, K. Kudo, and T. Ohtsuki
Utilization and Compensation of Interaction Torques During Ball-Throwing Movements
J Neurophysiol, April 1, 2003; 89(4): 1784 - 1796.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
S. M. Morton and A. J. Bastian
Relative Contributions of Balance and Voluntary Leg-Coordination Deficits to Cerebellar Gait Ataxia
J Neurophysiol, April 1, 2003; 89(4): 1844 - 1856.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
X. Liu, E. Robertson, and R. C. Miall
Neuronal Activity Related to the Visual Representation of Arm Movements in the Lateral Cerebellar Cortex
J Neurophysiol, March 1, 2003; 89(3): 1223 - 1237.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
H. P. Goodkin and W. T. Thach
Cerebellar Control of Constrained and Unconstrained Movements. I. Nuclear Inactivation
J Neurophysiol, February 1, 2003; 89(2): 884 - 895.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
H. P. Goodkin and W. T. Thach
Cerebellar Control of Constrained and Unconstrained Movements. II. EMG and Nuclear Activity
J Neurophysiol, February 1, 2003; 89(2): 896 - 908.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
P. Pigeon, S. B. Bortolami, P. DiZio, and J. R. Lackner
Coordinated Turn-and-Reach Movements. I. Anticipatory Compensation for Self-Generated Coriolis and Interaction Torques
J Neurophysiol, January 1, 2003; 89(1): 276 - 289.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
P. Pigeon, S. B. Bortolami, P. DiZio, and J. R. Lackner
Coordinated Turn-and-Reach Movements. II. Planning in an External Frame of Reference
J Neurophysiol, January 1, 2003; 89(1): 290 - 303.
[Abstract] [Full Text] [PDF]


Home page
J Child NeurolHome page
T. D. Sanger
Pathophysiology of Pediatric Movement Disorders
J Child Neurol, January 1, 2003; 18(1_suppl): S9 - S24.
[Abstract] [PDF]


Home page
J. Neurosci.Home page
E. Naito, T. Kochiyama, R. Kitada, S. Nakamura, M. Matsumura, Y. Yonekura, and N. Sadato
Internally Simulated Movement Sensations during Motor Imagery Activate Cortical Motor Areas and the Cerebellum
J. Neurosci., May 1, 2002; 22(9): 3683 - 3691.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
J. Hore, S. Watts, M. Leschuk, and A. MacDougall
Control of Finger Grip Forces in Overarm Throws Made by Skilled Throwers
J Neurophysiol, December 1, 2001; 86(6): 2678 - 2689.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
D. Timmann, R. Citron, S. Watts, and J. Hore
Increased Variability in Finger Position Occurs Throughout Overarm Throws Made by Cerebellar and Unskilled Subjects
J Neurophysiol, December 1, 2001; 86(6): 2690 - 2702.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
T. A. Martin, B. E. Greger, S. A. Norris, and W. T. Thach
Throwing Accuracy in the Vertical Direction During Prism Adaptation: Not Simply Timing of Ball Release
J Neurophysiol, May 1, 2001; 85(5): 2298 - 2302.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
M. Desmurget, H. Grea, J. S. Grethe, C. Prablanc, G. E. Alexander, and S. T. Grafton
Functional Anatomy of Nonvisual Feedback Loops during Reaching: A Positron Emission Tomography Study
J. Neurosci., April 15, 2001; 21(8): 2919 - 2928.
[Abstract] [Full Text] [PDF]


Home page
Physiol. Rev.Home page
G. Bosco and R. E. Poppele
Proprioception From a Spinocerebellar Perspective
Physiol Rev, April 1, 2001; 81(2): 539 - 568.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
G. M. Earhart and A. J. Bastian
Selection and Coordination of Human Locomotor Forms Following Cerebellar Damage
J Neurophysiol, February 1, 2001; 85(2): 759 - 769.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
G. L. Almeida, D. M. Corcos, and Z. Hasan
Horizontal-Plane Arm Movements With Direction Reversals Performed by Normal Individuals and Individuals With Down Syndrome
J Neurophysiol, October 1, 2000; 84(4): 1949 - 1960.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
S. E. Cooper, J. H. Martin, and C. Ghez
Effects of Inactivation of the Anterior Interpositus Nucleus on the Kinematic and Dynamic Control of Multijoint Movement
J Neurophysiol, October 1, 2000; 84(4): 1988 - 2000.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
N. Schweighofer and G. Ferriol
Diffusion of nitric oxide can facilitate cerebellar learning: A simulation study
PNAS, September 12, 2000; 97(19): 10661 - 10665.
[Abstract] [Full Text] [PDF]


Home page
BrainHome page
G. Deuschl, R. Wenzelburger, K. Loffler, J. Raethjen, and H. Stolze
Essential tremor and cerebellar dysfunction Clinical and kinematic analysis of intention tremor
Brain, August 1, 2000; 123(8): 1568 - 1580.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
A. J. Bastian, K. M. Zackowski, and W. T. Thach
Cerebellar Ataxia: Torque Deficiency or Torque Mismatch Between Joints?
J Neurophysiol, May 1, 2000; 83(5): 3019 - 3030.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
K. K. Wenger, K. L. Musch, and J. W. Mink
Impaired Reaching and Grasping After Focal Inactivation of Globus Pallidus Pars Interna in the Monkey
J Neurophysiol, November 1, 1999; 82(5): 2049 - 2060.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
C. E. Lang and A. J. Bastian
Cerebellar Subjects Show Impaired Adaptation of Anticipatory EMG During Catching
J Neurophysiol, November 1, 1999; 82(5): 2108 - 2119.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
J. Hore, S. Watts, and D. Tweed
Prediction and Compensation by an Internal Model for Back Forces During Finger Opening in an Overarm Throw
J Neurophysiol, September 1, 1999; 82(3): 1187 - 1197.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
D. Timmann, S. Watts, and J. Hore
Failure of Cerebellar Patients to Time Finger Opening Precisely Causes Ball High-Low Inaccuracy in Overarm Throws
J Neurophysiol, July 1, 1999; 82(1): 103 - 114.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
J. D. Coltz, M. T. V. Johnson, and T. J. Ebner
Cerebellar Purkinje Cell Simple Spike Discharge Encodes Movement Velocity in Primates during Visuomotor Arm Tracking
J. Neurosci., March 1, 1999; 19(5): 1782 - 1803.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
R. S. Turner, S. T. Grafton, J. R. Votaw, M. R. Delong, and J. M. Hoffman
Motor Subcircuits Mediating the Control of Movement Velocity: A PET Study
J Neurophysiol, October 1, 1998; 80(4): 2162 - 2176.
[Abstract] [Full Text] [PDF]


Home page
PhysiologyHome page
P. Weiss and M. Jeannerod
Getting a Grasp on Coordination
Physiology, April 1, 1998; 13(2): 70 - 75.
[Abstract] [Full Text] [PDF]


Home page
Learn. Mem.Home page
N Schweighofer and M A Arbib
A model of cerebellar metaplasticity.
Learn. Mem., January 1, 1998; 4(5): 421 - 428.
[Abstract] [PDF]


Home page
J. Neurophysiol.Home page
G. L. Gottlieb, Q. Song, G. L. Almeida, D.-A. Hong, and D. Corcos
Directional Control of Planar Human Arm Movement
J Neurophysiol, December 1, 1997; 78(6): 2985 - 2998.
[Abstract] [Full Text] [PDF]


Home page
J. Neurophysiol.Home page
C. J. Winstein, S. T. Grafton, and P. S. Pohl
Motor Task Difficulty and Brain Activity: Investigation of Goal-Directed Reciprocal Aiming Using Positron Emission Tomography
J Neurophysiol, March 1, 1997; 77(3): 1581 - 1594.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online