Browsing by Author "Hu, Kun"
Now showing items 1-14 of 14
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Cerebral Blood Flow Velocity and Periventricular White Matter Hyperintensities in Type 2 Diabetes
Novak, Vera; Last, David; Alsop, David; Abduljalil, Amir; Hu, Kun; Lepicovsky, Lukas; Cavallerano, Jerry; Lipsitz, Lewis (American Diabetes Association, 2006-07)OBJECTIVE Diabetes increases the risk for cerebromicrovascular disease, possibly through its effects on blood flow regulation. The aim of this study was to assess the effects of type 2 diabetes on blood flow velocities ... -
The Complexity of Standing Postural Control in Older Adults: A Modified Detrended Fluctuation Analysis Based upon the Empirical Mode Decomposition Algorithm
Zhou, Junhong; Manor, Bradley David; Liu, Dongdong; Hu, Kun; Zhang, Jue; Fang, Jing (Public Library of Science, 2013)Human aging into senescence diminishes the capacity of the postural control system to adapt to the stressors of everyday life. Diminished adaptive capacity may be reflected by a loss of the fractal-like, multiscale complexity ... -
Foot Pressure Distribution During Walking in Young and Old Adults
Hessert, Mary Josephine; Vyas, Mitul; Leach, Jason; Hu, Kun; Lipsitz, Lewis Arnold; Novak, Vera (BioMed Central, 2005)Background: Measurement of foot pressure distribution (FPD) is clinically useful for evaluation of foot and gait pathologies. The effects of healthy aging on FPD during walking are not well known. This study evaluated FPD ... -
Fractal Patterns of Neural Activity Exist within the Suprachiasmatic Nucleus and Require Extrinsic Network Interactions
Hu, Kun; Meijer, Johanna H.; Shea, Steven Andrew; vanderLeest, Henk Tjebbe; Pittman-Polletta, Benjamin Rafael; Houben, Thijs; van Oosterhout, Floor; Deboer, Tom; Scheer, Frank A.J.L. (Public Library of Science, 2012)The mammalian central circadian pacemaker (the suprachiasmatic nucleus, SCN) contains thousands of neurons that are coupled through a complex network of interactions. In addition to the established role of the SCN in ... -
Global and Regional Effects of Type 2 Diabetes on Brain Tissue Volumes and Cerebral Vasoreactivity
Last, David; Alsop, David; Abduljalil, Amir; Marquis, Robert P.; de Bazelaire, Cedric; Hu, Kun; Cavallerano, Jerry; Novak, Vera (American Diabetes Association, 2007-02-08)OBJECTIVE—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. RESEARCH DESIGN AND METHODS—CBF was ... -
Impaired Cerebral Autoregulation Is Associated with Brain Atrophy and Worse Functional Status in Chronic Ischemic Stroke
Aoi, Mikio C.; Hu, Kun; Lo, Men-Tzung; Selim, Magdy H.; Olufsen, Mette S.; Novak, Vera (Public Library of Science, 2012)Dynamic cerebral autoregulation (dCA) is impaired following stroke. However, the relationship between dCA, brain atrophy, and functional outcomes following stroke remains unclear. In this study, we aimed to determine whether ... -
Interactive Effects of Dorsomedial Hypothalamic Nucleus and Time-Restricted Feeding on Fractal Motor Activity Regulation
Lo, Men-Tzung; Chiang, Wei-Yin; Hsieh, Wan-Hsin; Escobar, Carolina; Buijs, Ruud M.; Hu, Kun (Frontiers Media S.A., 2016)One evolutionary adaptation in motor activity control of animals is the anticipation of food that drives foraging under natural conditions and is mimicked in laboratory with daily scheduled food availability. Food anticipation ... -
Noninvasive fractal biomarker of clock neurotransmitter disturbance in humans with dementia
Hu, Kun; Harper, David G.; Shea, Steven A.; Stopa, Edward G.; Scheer, Frank A. J. L. (Nature Publishing Group, 2013)Human motor activity has a robust, intrinsic fractal structure with similar patterns from minutes to hours. The fractal activity patterns appear to be physiologically important because the patterns persist under different ... -
A Nonlinear Dynamic Approach Reveals a Long-Term Stroke Effect on Cerebral Blood Flow Regulation at Multiple Time Scales
Hu, Kun; Lo, Men-Tzung; Peng, Chung-Kang; Liu, Yanhui; Novak, Vera (Public Library of Science, 2012)Cerebral autoregulation (CA) is an important vascular control mechanism responsible for relatively stable cerebral blood flow despite changes of systemic blood pressure (BP). Impaired CA may leave brain tissue unprotected ... -
On Holo-Hilbert spectral analysis: a full informational spectral representation for nonlinear and non-stationary data
Huang, Norden E.; Hu, Kun; Yang, Albert C. C.; Chang, Hsing-Chih; Jia, Deng; Liang, Wei-Kuang; Yeh, Jia Rong; Kao, Chu-Lan; Juan, Chi-Hung; Peng, Chung Kang; Meijer, Johanna H.; Wang, Yung-Hung; Long, Steven R.; Wu, Zhauhua (The Royal Society Publishing, 2016)The Holo-Hilbert spectral analysis (HHSA) method is introduced to cure the deficiencies of traditional spectral analysis and to give a full informational representation of nonlinear and non-stationary data. It uses a nested ... -
Outlier-resilient complexity analysis of heartbeat dynamics
Lo, Men-Tzung; Chang, Yi-Chung; Lin, Chen; Young, Hsu-Wen Vincent; Lin, Yen-Hung; Ho, Yi-Lwun; Peng, Chung-Kang; Hu, Kun (Nature Publishing Group, 2015)Complexity in physiological outputs is believed to be a hallmark of healthy physiological control. How to accurately quantify the degree of complexity in physiological signals with outliers remains a major barrier for ... -
Probing the Fractal Pattern of Heartbeats in Drosophila Pupae by Visible Optical Recording System
Lin, Chen; Chang, Yi-Chung; Cheng, Ya-Chen; Lai, Po-Jung; Yeh, Chien-Hung; Hsieh, Wan-Hsin; Hu, Kun; Wu, June-Tai; Lee, Hsiu-Hsiang; Lo, Men-Tzung; Ho, Yi-Lwun (Nature Publishing Group, 2016)Judiciously tuning heart rates is critical for regular cardiovascular function. The fractal pattern of heartbeats — a multiscale regulation in instantaneous fluctuations — is well known for vertebrates. The most primitive ... -
Progression of Dementia Assessed by Temporal Correlations of Physical Activity: Results From a 3.5-Year, Longitudinal Randomized Controlled Trial
Hu, Kun; Riemersma - van der Lek, Rixt F.; Patxot, Melissa; Li, Peng; Shea, Steven A.; Scheer, Frank A. J. L.; Van Someren, Eus J. W. (Nature Publishing Group, 2016)Cross-sectional studies show that activity fluctuations in healthy young adults possess robust temporal correlations that become altered with aging, and in dementia and depression. This study was designed to test whether ... -
White Matter Hyperintensities and Dynamics of Postural Control
Novak, Vera; Haertle, Mareile; Zhao, Peng; Hu, Kun; Munshi, Medha; Novak, Peter; Abduljalil, Amir; Alsop, David (Elsevier BV, 2009-07)Background White matter hyperintensities (WMHs) on MRI have been associated with age, cardiovascular risk factors and falls in the elderly. This study evaluated the relationship between WMHs and dynamics of postural control ...