Results 111 to 120 of about 24,907 (232)

Screens, Teens, and Sleep: Is the Impact of Nighttime Screen Use on Sleep Driven by Physiological Arousal?

Journal of Sleep Research, EarlyView.
ABSTRACT Few studies have objectively measured both screens and sleep in real‐world settings. This study uses repeated measures to assess heart rate during evening screen use, providing new insights into how these behaviours relate to adolescent sleep. Screen use was recorded using wearable cameras over four nights in 70 youth (37% indigenous Māori, 42%
Kim A. Meredith‐Jones, Jillian J. Haszard, Barbara C. Galland, Shay‐Ruby Wickham, Bradley J. Brosnan, Takiwai Russell‐Camp, Rachael W. Taylor   +6 more
wiley   +1 more source

Filter and Sampling Rate Optimization for PPG-Based Detection of Autonomic Dysfunction: An ECG-guided Approach

Measurement Science Review
Photoplethysmography (PPG) is well suited for wearable health applications, but has a lower frequency spectrum than electrocardiography (ECG) and is more affected by motion artifacts.
Kao Yi-Hui, Shahmirzadi Danyal, Hsieh Sung-Tsang, Wang Wen-Fong   +3 more
doaj   +1 more source

Effects of the angle of head‐down tilt on dynamic cerebral autoregulation during combined exposure to cephalad fluid shift and mild hypercapnia

Experimental Physiology, EarlyView.
Abstract Astronauts experience combined exposure to a cephalad fluid shift and mild hypercapnia during space missions, potentially contributing to health problems. Such combined exposure may weaken dynamic cerebral autoregulation. The magnitude of cephalad fluid shift varies between individuals, and dynamic cerebral autoregulation may be affected more ...
Tomokazu Kato, Yojiro Ogawa, Ken‐ichi Iwasaki   +2 more
wiley   +1 more source

Use of zero-frequency resonator for automatically detecting systolic peaks of photoplethysmogram signal

Healthcare Technology Letters, 2019
This work investigates the application of zero-frequency resonator (ZFR) for detecting systolic peaks of photoplethysmogram (PPG) signals. Based on the authors’ studies, they propose an automated noise-robust method, which consists of the central ...
Simhadri Vadrevu, M. Sabarimalai Manikandan   +1 more
doaj   +1 more source

Blood flow restriction: The acute effects of body tilting and reduced gravity analogues on limb occlusion pressure

Experimental Physiology, EarlyView.
Abstract Blood flow restriction (BFR) has been identified as a potential countermeasure to mitigate physiological deconditioning during spaceflight. Guidelines recommend that tourniquet pressure be prescribed relative to limb occlusion pressure (LOP); however, it is unclear whether body tilting or reduced gravity analogues influence LOP.
Patrick Swain, Nick Caplan, Luke Hughes
wiley   +1 more source

Effects of Wrist Sensor Placement on PPG Signal Quality

Current Directions in Biomedical Engineering
Photoplethysmography (PPG) is a key sensing modality in wearable devices for monitoring cardiovascular parameters. Despite widespread use, wrist-based PPG measurements often suffer from signal degradation due to anatomical variability and suboptimal ...
Meier Dominik, Bandel Torsten, Baili Asrar, Dömer Benno   +3 more
doaj   +1 more source

Investigation of Lower-limb Tissue Perfusion during Loading [PDF]

, 2002
An extant tissue indentor used for amputee residual limb tissue indentation studies was modified to include laser Doppler flowmetry (LDF) to enable measurement of tissue perfusion during indentation.
Silver-Thorn, Barbara
core   +1 more source

Individuals with persisting post‐concussion symptoms with physiological subtype demonstrate altered cardiovascular and autonomic responses to face cooling

Experimental Physiology, EarlyView.
Abstract Individuals with persisting post‐concussion symptoms with physiological subtype (PPCS‐P) demonstrate exercise intolerance due to exacerbation of concussion‐like symptoms during incremental exercise. We tested the hypothesis that individuals with PPCS‐P (n = 12) would have a blunted cardiac autonomic response to face cooling compared to healthy
Phillip J. Wallace, Steve Lidstone, Josh G. Nowlan, Johnathan Ljubanovich, Brandon J. McKinlay, Stephen A. Klassen, Stephen S. Cheung   +6 more
wiley   +1 more source

How Nonlinear-Type Time-Frequency Analysis Can Help in Sensing Instantaneous Heart Rate and Instantaneous Respiratory Rate from Photoplethysmography in a Reliable Way

Frontiers in Physiology, 2017
Despite the population of the noninvasive, economic, comfortable, and easy-to-install photoplethysmography (PPG), it is still lacking a mathematically rigorous and stable algorithm which is able to simultaneously extract from a single-channel PPG signal ...
Antonio Cicone, Hau-Tieng Wu, Hau-Tieng Wu   +2 more
doaj   +1 more source

Optimizing cerebrovascular endothelial health through shear stress modulation

Experimental Physiology, EarlyView.
Abstract The endothelium plays a pivotal role in regulating cerebrovascular blood flow, and its dysfunction increases the risk of cerebrovascular disease. Endothelial shear stress, a primary mechanical stimulus for endothelial nitric oxide production, is a key modulator of vascular adaptation.
Erika Iwamoto, Rintaro Sakamoto, Darren P. Casey   +2 more
wiley   +1 more source