45 research outputs found
Associations of Subjective Sleep Quality with Wearable Device-Derived Resting Heart Rate During REM Sleep and Non-REM Sleep in a Cohort of Japanese Office Workers
Olivia Sjöland,1,2 Thomas Svensson,1– 3 Kaushalya Madhawa,1 Hoang NT,1 Ung-Il Chung,1,3,4 Akiko Kishi Svensson1,2,5 1Precision Health, Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan; 2Department of Clinical Sciences, Lund University, Skåne University Hospital, Malmö, Sweden; 3Graduate School of Health Innovation, Kanagawa University of Human Services, Kawasaki-Ku, Kawasaki-Shi, Kanagawa, Japan; 4Clinical Biotechnology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, Tokyo, Japan; 5Department of Diabetes and Metabolic Diseases, The University of Tokyo, Tokyo, JapanCorrespondence: Thomas Svensson, Precision Health, Department of Bioengineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan, Tel +81-3-5841-4737, Email [email protected]: Associations between subjective sleep quality and stage-specific heart rate (HR) may have important clinical relevance when aiming to optimize sleep and overall health. The majority of previously studies have been performed during short periods under laboratory-based conditions. The aim of this study was to investigate the associations of subjective sleep quality with heart rate during REM sleep (HR REMS) and non-REM sleep (HR NREMS) using a wearable device (Fitbit Versa).Methods: This is a secondary analysis of data from the intervention group of a randomized controlled trial (RCT) performed between December 3, 2018, and March 2, 2019, in Tokyo, Japan. The intervention group consisted of 179 Japanese office workers with metabolic syndrome (MetS), Pre-MetS or a high risk of developing MetS. HR was collected with a wearable device and sleep quality was assessed with a mobile application where participants answered The St. Mary’s Hospital Sleep Questionnaire. Both HR and sleep quality was collected daily for a period of 90 days. Associations of between-individual and within-individual sleep quality with HR REMS and HR NREMS were analyzed with multi-level model regression in 3 multivariate models.Results: The cohort consisted of 92.6% men (n=151) with a mean age (± standard deviation) of 44.1 (± 7.5) years. A non-significant inverse between-individual association was observed for sleep quality with HR REMS (HR REMS − 0.18; 95% CI − 0.61, 0.24) and HR NREMS (HR NREMS − 0.23; 95% CI − 0.66, 0.21), in the final multivariable adjusted models; a statistically significant inverse within-individual association was observed for sleep quality with HR REMS (HR REMS − 0.21 95% CI − 0.27, − 0.15) and HR NREMS (HR NREMS − 0.21 95% CI − 0.27, − 0.14) after final adjustments for covariates.Conclusion: The present study shows a statistically significant within-individual association of subjective sleep quality with HR REMS and HR NREMS. These findings emphasize the importance of considering sleep quality on the individual level. The results may contribute to early detection and prevention of diseases associated with sleep quality which may have important implications on public health given the high prevalence of sleep disturbances in the population.Keywords: sleep quality, heart rate, sleep stages, REMS, NREMS, wearable devic
Identification of Markers that Distinguish Monocyte-Derived Fibrocytes from Monocytes, Macrophages, and Fibroblasts
The processes that drive fibrotic diseases are complex and include an influx of peripheral blood monocytes that can differentiate into fibroblast-like cells called fibrocytes. Monocytes can also differentiate into other cell types, such as tissue macrophages. The ability to discriminate between monocytes, macrophages, fibrocytes, and fibroblasts in fibrotic lesions could be beneficial in identifying therapies that target either stromal fibroblasts or fibrocytes. and in sections from human lung. We found that markers such as CD34, CD68, and collagen do not effectively discriminate between the four cell types. In addition, IL-4, IL-12, IL-13, IFN-γ, and SAP differentially regulate the expression of CD32, CD163, CD172a, and CD206 on both macrophages and fibrocytes. Finally, CD49c (α3 integrin) expression identifies a subset of fibrocytes, and this subset increases with time in culture.These results suggest that discrimination of monocytes, macrophages, fibrocytes, and fibroblasts in fibrotic lesions is possible, and this may allow for an assessment of fibrocytes in fibrotic diseases
Tail Current Noise Suppression in RF CMOS VCOs
This paper presents the experimental results of two different techniques, inductive degeneration and capacitive filtering, for reducing the phase noise in tail-biased RF CMOS voltage-controlled oscillators (VCOs). Both techniques prevent the low-frequency tail current noise from being converted into phase noise. The techniques are applied to two distinct VCO designs, showing that the largest phase noise reduction (up to 6-7 dB at 3-MHz offset frequency from the carrier) is achieved via inductive degeneration. Capacitive filtering, however, also substantially reduces the phase noise at high offset frequencies and may therefore become a valid alternative to inductive degeneration, as discrete capacitors are of more common use than discrete inductors
A Class-AB 1.65GHz-2GHz Broadband CMOS Medium Power Amplifier
In this paper a single stage broadband CMOS RF power amplifier is presented. The power amplifier is fabricated in a 0:25¹m CMOS process. Measurements with a 2:5V supply voltage show an output power of 18:5 dBm with an associated PAE of 16% at the 1-dB compression point. The measured gain is 5.1 § 0:5 dB from 1.65 to 2 GHz. Simulated and measured results agree reasonably well
850/900/1800/1900MHz Quad-Band CMOS Medium Power Amplifier
This paper presents a two-stage quad-band CMOS RF power amplifier. The power amplifier is fabricated in a 0.25 mum CMOS process. The measured 1-dB compression point between 800 and 900 MHz is 15 dBm plusmn 0.2 dB with maximum 18% PAE, and between 1800 and 1900MHz is 17.5dBm plusmn 0.7dB with maximum 17% PAE. The measured gains in the two bands are 23.6 dB plusmn 0.7 dB and 13 dB plusmn 2.1 dB, respectively
High-resolution passive phase shifters for adaptive duplexing applications in SOS process
Two high-resolution passive delay line phase shifters in silicon-on-sapphire are compared. Both make use of digitally tuned capacitor loaded π sections to obtain 360° phase control. The first has a nominal resolution of 9-bit and uses ten sections, yielding an insertion loss (IL) of 12.6 dB at 1.4 GHz. The second employs a center tapped auto-transformer to provide 180° of phase shift, reducing both size and the IL while enabling a further 1-bit improvement in resolution. The measured IL in the 1.8-2.4-GHz frequency range is less than 7.3 dB. Stacked field-effect transistors were employed as switches to increase the power-handling capability. An input referred third intercept point (IIP3) of + 39 and + 54 dBm were measured for the first and second circuits, respectively. © 2014 IEEE