Kun Hu

Summary

Affiliation: Harvard University
Country: USA

Publications

  1. pmc The endogenous circadian pacemaker imparts a scale-invariant pattern of heart rate fluctuations across time scales spanning minutes to 24 hours
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, Massachusetts 02215, USA
    J Biol Rhythms 23:265-73. 2008
  2. pmc Nonlinear pressure-flow relationship is able to detect asymmetry of brain blood circulation associated with midline shift
    Kun Hu
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
    J Neurotrauma 26:227-33. 2009
  3. pmc The circadian pacemaker generates similar circadian rhythms in the fractal structure of heart rate in humans and rats
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02115, USA
    Cardiovasc Res 80:62-8. 2008
  4. pmc Nonlinear assessment of cerebral autoregulation from spontaneous blood pressure and cerebral blood flow fluctuations
    Kun Hu
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, 812 Stoneman Bldg, 330 Brookline Avenue, Boston, MA 02115, USA
    Cardiovasc Eng 8:60-71. 2008
  5. pmc The suprachiasmatic nucleus functions beyond circadian rhythm generation
    K Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Sleep Disorders BIDMC, 75 Francis Street, Boston, MA 02215, USA
    Neuroscience 149:508-17. 2007
  6. pmc Noninvasive fractal biomarker of clock neurotransmitter disturbance in humans with dementia
    Kun Hu
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, MA 02115, United States
    Sci Rep 3:2229. 2013
  7. pmc Cross-correlation of instantaneous phase increments in pressure-flow fluctuations: applications to cerebral autoregulation
    Zhi Chen
    Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 73:031915. 2006
  8. pmc Cardiolocomotor coupling in young and elderly people
    Vera Novak
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
    J Gerontol A Biol Sci Med Sci 62:86-92. 2007
  9. pmc Endogenous circadian rhythm in human motor activity uncoupled from circadian influences on cardiac dynamics
    Plamen Ch Ivanov
    Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215, USA
    Proc Natl Acad Sci U S A 104:20702-7. 2007
  10. pmc Fractal patterns of neural activity exist within the suprachiasmatic nucleus and require extrinsic network interactions
    Kun Hu
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA, USA
    PLoS ONE 7:e48927. 2012

Detail Information

Publications32

  1. pmc The endogenous circadian pacemaker imparts a scale-invariant pattern of heart rate fluctuations across time scales spanning minutes to 24 hours
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, Massachusetts 02215, USA
    J Biol Rhythms 23:265-73. 2008
    ..These results demonstrate that experimental manipulations (e.g., SCN lesion) can be used to begin to model and understand the origin of scale-invariant behavior in a neurophysiological system...
  2. pmc Nonlinear pressure-flow relationship is able to detect asymmetry of brain blood circulation associated with midline shift
    Kun Hu
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
    J Neurotrauma 26:227-33. 2009
    ..Moreover, mean pressure-flow phase shift is sensitive to the displacement of midline of the brain, and may potentially serve as a marker of asymmetry of cerebral autoregulation...
  3. pmc The circadian pacemaker generates similar circadian rhythms in the fractal structure of heart rate in humans and rats
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02115, USA
    Cardiovasc Res 80:62-8. 2008
    ....
  4. pmc Nonlinear assessment of cerebral autoregulation from spontaneous blood pressure and cerebral blood flow fluctuations
    Kun Hu
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, 812 Stoneman Bldg, 330 Brookline Avenue, Boston, MA 02115, USA
    Cardiovasc Eng 8:60-71. 2008
    ....
  5. pmc The suprachiasmatic nucleus functions beyond circadian rhythm generation
    K Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Sleep Disorders BIDMC, 75 Francis Street, Boston, MA 02215, USA
    Neuroscience 149:508-17. 2007
    ..Identification of the control nodes of a neural network responsible for scale invariance is the critical first step in understanding the neurophysiological origin of scale invariance/self-similarity...
  6. pmc Noninvasive fractal biomarker of clock neurotransmitter disturbance in humans with dementia
    Kun Hu
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, MA 02115, United States
    Sci Rep 3:2229. 2013
    ..These findings suggest that the SCN impacts human activity regulation at multiple time scales and that disrupted fractal activity may serve as a non-invasive biomarker of SCN neurodegeneration in dementia. ..
  7. pmc Cross-correlation of instantaneous phase increments in pressure-flow fluctuations: applications to cerebral autoregulation
    Zhi Chen
    Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 73:031915. 2006
    ....
  8. pmc Cardiolocomotor coupling in young and elderly people
    Vera Novak
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
    J Gerontol A Biol Sci Med Sci 62:86-92. 2007
    ..Walking is a complex act that requires the coordination of locomotor, cardiovascular, and autonomic systems. Aging affects each of these systems and may alter physiological mechanisms regulating the interactions between them...
  9. pmc Endogenous circadian rhythm in human motor activity uncoupled from circadian influences on cardiac dynamics
    Plamen Ch Ivanov
    Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215, USA
    Proc Natl Acad Sci U S A 104:20702-7. 2007
    ..m...
  10. pmc Fractal patterns of neural activity exist within the suprachiasmatic nucleus and require extrinsic network interactions
    Kun Hu
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA, USA
    PLoS ONE 7:e48927. 2012
    ..Such a fractal control network could underlie the fractal regulation observed in many physiological functions that involve the SCN, including motor control and heart rate regulation...
  11. pmc Global and regional effects of type 2 diabetes on brain tissue volumes and cerebral vasoreactivity
    David Last
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, 110 Francis St, Boston, MA 02215, USA
    Diabetes Care 30:1193-9. 2007
    ..The aim of this study was to evaluate the regional effects of type 2 diabetes and associated conditions on cerebral tissue volumes and cerebral blood flow (CBF) regulation...
  12. pmc Physiological complexity and system adaptability: evidence from postural control dynamics of older adults
    Brad Manor
    Division of Gerontology, Beth Israel Deaconess Medical Center, 110 Francis St Suite 1B, Boston, MA 02215, USA
    J Appl Physiol (1985) 109:1786-91. 2010
    ..Relatively low baseline complexity may, therefore, indicate control systems that are more vulnerable to cognitive and other stressors...
  13. pmc Nonlinear phase interaction between nonstationary signals: a comparison study of methods based on Hilbert-Huang and Fourier transforms
    Men Tzung Lo
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 79:061924. 2009
    ..Furthermore, we propose certain strategies that can be implemented in the TFA and the MMPF methods to reduce the effects of nonstationarities, thus improving the performances of the two methods...
  14. pmc Non-random fluctuations and multi-scale dynamics regulation of human activity
    Kun Hu
    Center for Polymer Studies, Department of Physics, Boston University, Boston, MA 02215, USA
    Physica A 337:307-18. 2004
    ....
  15. pmc A nonlinear dynamic approach reveals a long-term stroke effect on cerebral blood flow regulation at multiple time scales
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
    PLoS Comput Biol 8:e1002601. 2012
    ....
  16. pmc Impact of the human circadian system, exercise, and their interaction on cardiovascular function
    Frank A J L Scheer
    Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA 02115, USA
    Proc Natl Acad Sci U S A 107:20541-6. 2010
    ....
  17. pmc Endogenous circadian rhythm in an index of cardiac vulnerability independent of changes in behavior
    Kun Hu
    Center for Polymer Studies and Department of Physics, Boston University, Boston, MA 02215, USA
    Proc Natl Acad Sci U S A 101:18223-7. 2004
    ....
  18. ncbi request reprint Spurious detection of phase synchronization in coupled nonlinear oscillators
    Limei Xu
    Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 73:065201. 2006
    ....
  19. pmc Existence of an endogenous circadian blood pressure rhythm in humans that peaks in the evening
    Steven A Shea
    Brigham and Women s Hospital, Harvard Medical School, Boston, MA 02115, USA
    Circ Res 108:980-4. 2011
    ..Whether the endogenous circadian control system contributes to this daily BP variation has not been determined under appropriately controlled conditions...
  20. pmc Endogenous circadian rhythm in vasovagal response to head-up tilt
    Kun Hu
    Division of Sleep Medicine, Harvard Medical School, 221 Longwood Ave, 044 BLI, Boston, MA 02115, USA
    Circulation 123:961-70. 2011
    ..This study tested the hypothesis that the circadian system modulates cardiovascular responses to postural stress, leading to increased susceptibility to syncope at specific times of day...
  21. pmc Cerebral flow velocities during daily activities depend on blood pressure in patients with chronic ischemic infarctions
    Vera Novak
    Division of Gerontology, Beth Israel Deaconess Medical Center, 110 Francis Street, Boston, MA 02215, USA
    Stroke 41:61-6. 2010
    ..Target blood pressure (BP) values for optimal cerebral perfusion after an ischemic stroke are still debated. We sought to examine the relationship between BP and cerebral blood flow velocities (BFVs) during daily activities...
  22. pmc Reduction of scale invariance of activity fluctuations with aging and Alzheimer's disease: Involvement of the circadian pacemaker
    Kun Hu
    Division of Sleep Medicine, Brigham and Women s Hospital, Harvard Medical School, Boston, MA 02115, USA
    Proc Natl Acad Sci U S A 106:2490-4. 2009
    ..Thus, aging and AD significantly attenuate the scale invariance of activity fluctuations over multiple time scales. This attenuation may reflect functional changes of the SCN...
  23. pmc Cerebral blood flow velocity and periventricular white matter hyperintensities in type 2 diabetes
    Vera Novak
    Division of Gerontology, Beth Israel Deaconess Medical Center, 110 Francis St, Boston, MA 02215, USA
    Diabetes Care 29:1529-34. 2006
    ....
  24. ncbi request reprint Effect of nonlinear filters on detrended fluctuation analysis
    Zhi Chen
    Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 71:011104. 2005
    ..We systematically test the performance of the DFA method when estimating long-range power-law correlations in the output signals for different parameter values in the three types of filters and the three analytic functions we consider...
  25. pmc Posturo-respiratory synchronization: effects of aging and stroke
    Brad D Manor
    Division of Gerontology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
    Gait Posture 36:254-9. 2012
    ..As evidenced by increased posturo-respiratory synchronization with advanced age and central lesion, this novel metric may be used as a clinical marker of altered postural control...
  26. pmc Altered control of postural sway following cerebral infarction: a cross-sectional analysis
    B Manor
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
    Neurology 74:458-64. 2010
    ..We examined dependence upon vision and noninfarcted regional brain tissue volumes for postural control in individuals with right and left hemisphere middle cerebral artery (MCA) infarcts...
  27. pmc White matter hyperintensities and dynamics of postural control
    Vera Novak
    Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
    Magn Reson Imaging 27:752-9. 2009
    ..This study evaluated the relationship between WMHs and dynamics of postural control in older adults without history of falls...
  28. doi request reprint Detecting phase-amplitude coupling with high frequency resolution using adaptive decompositions
    Benjamin Pittman-Polletta
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA Department of Mathematics and Statistics, Boston University, Boston, MA, USA Electronic address
    J Neurosci Methods 226:15-32. 2014
    ....
  29. pmc The role of the circadian system in fractal neurophysiological control
    Benjamin R Pittman-Polletta
    Medical Biodynamics Program, Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA, 02115, U S A Medical Chronobiology Program, Division of Sleep Medicine, Brigham and Women s Hospital, Boston, MA, 02115, U S A Division of Sleep Medicine, Harvard Medical School, Boston, MA, 02115, U S A
    Biol Rev Camb Philos Soc 88:873-94. 2013
    ..In this review, we sketch the emerging picture of the developing interdisciplinary field of fractal neurophysiology by examining the circadian system's role in fractal regulation. ..
  30. pmc Foot pressure distribution during walking in young and old adults
    Mary Josephine Hessert
    Division of Gerontology, Beth Israel Deaconess Medical Center Harvard Medical School, Boston, MA 02215, USA
    BMC Geriatr 5:8. 2005
    ..The effects of healthy aging on FPD during walking are not well known. This study evaluated FPD during normal walking in healthy young and elderly subjects...
  31. ncbi request reprint Effect of nonstationarities on detrended fluctuation analysis
    Zhi Chen
    Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215, USA
    Phys Rev E Stat Nonlin Soft Matter Phys 65:041107. 2002
    ....
  32. pmc Vasoreactivity and peri-infarct hyperintensities in stroke
    P Zhao
    Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
    Neurology 72:643-9. 2009
    ..We investigated the regional differences in CO2 vasoreactivity (CO2 VR) and their relationships to peri-infarct T2 hyperintensities (PIHs), chronic infarct volumes, and clinical outcomes...