Continuous Monitoring of Heart Rate Variability in Free-Living Conditions Using Wearable Sensors: Exploratory Observational Study.

Background: Wearable physiological monitoring devices are promising tools for remote monitoring and early detection of potential health changes of interest. The widespread adoption of such an approach across communities and over long periods of time will require an automated data platform for collecting, processing, and analyzing relevant health information.

Objective: In this study, we explore prospective monitoring of individual health through an automated data collection, metrics extraction, and health anomaly analysis pipeline in free-living conditions over a continuous monitoring period of several months with a focus on viral respiratory infections, such as influenza or COVID-19.

Feasibility of combining biosensor and ecological momentary assessment to measure stress experiences among economically disadvantaged adolescents.

Adolescent stress is complex and impairing. Novel measures are needed to understand stress variability within individuals over time from a physiological as well as a subjective perspective. To test the feasibility of combining ecological momentary assessment (EMA) and wearable biosensors to assess adolescent stress, using an idiographic approach with experience sampling methods.

Wearable Sensor-Based Detection of Influenza in Presymptomatic and Asymptomatic Individuals.

Background: The COVID-19 pandemic highlighted the need for early detection of viral infections in symptomatic and asymptomatic individuals to allow for timely clinical management and public health interventions.

Methods: Twenty healthy adults were challenged with an influenza A (H3N2) virus and prospectively monitored from 7 days before through 10 days after inoculation, using wearable electrocardiogram and physical activity sensors. This framework allowed for responses to be accurately referenced to the infection event.

Cardiac-based detection of seizures in children with epilepsy.

Introduction: We evaluated a multi-parametric approach to seizure detection using cardiac and activity features to detect a wide range of seizures across different people using the same model.

Methods: Electrocardiogram (ECG) and accelerometer data were collected from a chest-worn sensor from 62 children aged 2-17 years undergoing video-electroencephalogram monitoring for clinical care. ECG data from 5 adults aged 31-48 years who experienced focal seizures were also analyzed from the PhysioNet database.

Characterization of fecal sludge as biomass feedstock for thermal treatment in the southern Indian state of Tamil Nadu.

: Transformative sanitation technologies aim to treat fecal sludge (FS) by thermal processes and recover resources from it. There is a paucity of data describing the relevant properties of FS as viable feedstock for thermal treatment in major geographical target areas, such as India. : This study characterized FS collected from septic tanks in two cities located in the Indian southern state of Tamil Nadu.

Optimal design of an electrochemical reactor for blackwater treatment.

Electrolysis of blackwater for disinfection and nutrient removal is a portable and scalable technology that can lessen the need for cities to construct large-scale wastewater treatment infrastructure and enable the safe onsite reuse of blackwater. Several systems for treating wastewater from single toilets are described in the literature, but there are few examples of systems designed to use electrolysis to treat blackwater from nearby toilets, which is a situation more common in densely packed urban living environments. In order to scale a single toilet electrolysis system to one that could service multiple toilets, computational fluid dynamic analysis was used to optimize the electrochemical reactor design, and laboratory and field-testing were used to confirm results.

Feasibility of Mild Traumatic Brain Injury Assessment Based on Cardiovascular Response to Postural Change.

Objective: To determine the feasibility of short-term cardiovascular responses to postural change as a screening tool for mild traumatic brain injury (mTBI), using heart rate metrics that can be measured with a wearable electrocardiogram sensor.

Setting: Military TBI clinic.

Design: Data collected from active-duty service members who had sustained a medically diagnosed mTBI within the prior 72 hours and from age- and sex-matched controls.

Resolving the relative contributions of cistern and pour flushing to toilet water usage: Measurements from urban test sites in India.

A challenge in water reuse for toilet flushing in India and other Asian countries derives from pour flushing practices. It is a common assumption that the amount of pour flushed water used for personal cleansing is small in comparison to the cistern flush volume, however there is a knowledge gap regarding the actual contribution of each water source to the blackwater amount. In this study, digital water meters were used to measure the fraction of water from personal wash tap relative to cistern water that is used for toilet flushing.

An analysis of stereotypical motor movements and cardiovascular coupling in individuals on the autism spectrum.

One of the core diagnostic features of autism spectrum disorder (ASD) is engagement in stereotypical motor movements, although the etiology of this repetitive behavior is unknown. Since the 1960s, it has been hypothesized that stereotypical motor movements serve a homeostatic regulation function, and thereby a putative coupling mechanism to cardiovascular arousal. However, to date, surprisingly few reports explicitly assess cardio-somatic coupling and stereotypical motor movements.

Soil-transmitted helminth eggs assessment in wastewater in an urban area in India.

Water quality and sanitation are inextricably linked to prevalence and control of soil-transmitted helminth infections, a public health concern in resource-limited settings. India bears a large burden of disease associated with poor sanitation. Transformative onsite sanitation technologies are being developed that feature elimination of pathogens including helminth eggs in wastewater treatment.

Automated Detection of Repetitive Motor Behaviors as an Outcome Measurement in Intellectual and Developmental Disabilities.

Repetitive sensory motor behaviors are a direct target for clinical treatment and a potential treatment endpoint for individuals with intellectual or developmental disabilities. By removing the burden associated with video annotation or direct observation, automated detection of stereotypy would allow for longer term monitoring in ecologic settings. We report automated detection of common stereotypical motor movements using commercially available accelerometers affixed to the body and a generalizable detection algorithm.

Automated respiratory sinus arrhythmia measurement: Demonstration using executive function assessment.

Respiratory sinus arrhythmia (RSA) is a quantitative metric that reflects autonomic nervous system regulation and provides a physiological marker of attentional engagement that supports cognitive and affective regulatory processes. RSA can be added to executive function (EF) assessments with minimal participant burden because of the commercial availability of lightweight, wearable electrocardiogram (ECG) sensors. However, the inclusion of RSA data in large data collection efforts has been hindered by the time-intensive processing of RSA.

Biometrics and Policing: A Protocol for Multichannel Sensor Data Collection and Exploratory Analysis of Contextualized Psychophysiological Response During Law Enforcement Operations.

Background: Stress experienced by law enforcement officers is often extreme and is in many ways unique among professions. Although past research on officer stress is informative, it is limited, and most studies measure stress using self-report questionnaires or observational studies that have limited generalizability. We know of no research studies that have attempted to track direct physiological stress responses in high fidelity, especially within an operational police setting.

Challenging present concepts in compression therapy: static stiffness index is not consistent and not clinically relevant.

Once a circumferential force is delivered to a limb by a compression device, assuming the tension within the device remains constant, any change in the total force is dependent upon a change in circumference of the limb, with the rate of change (excluding fabric creep) being dependent on the stress strain curve of the device. This article addresses the pre-conceived and well-accepted principle that interface compression delivered by a compression device substantially increases with the position of the limb, based on the positions of sitting (non-weight bearing) to standing and/or during muscle activity (ankle dorsiflexion). Using engineering parameters and clinical measurements, the authors demonstrate that changes in interface pressure are minimal if any, and that the current concept should be modified accordingly.

Simulated pressure changes in multilayer, multicomponent wrap systems when transitioning from rest to standing.

Objective: The objective of this paper was to investigate the pressure applied to the lower leg by multilayer, multicomponent wrap systems, in different positions Method: The stretch profiles of five multilayer, multicomponent wrap systems were tested, three 2-layer and two 4-layer systems. These were quantified in the laboratory using a tensile testing device. The circumference of the lower leg was measured on healthy participants in three locations (ankle, B1 level, and calf) in three different postures (rest, dorsiflexion, and standing).

Research into fabrics used in compression therapy and assessment of their impact on treatment regimens.

Unlabelled: The objective of this paper is to provide a definition for interface compression that uses essential principles of engineering science. This definition discusses factors that influence the amount of applied pressure, including the size of the limb, the amount of fabric tension (graduated pressure profile), the number of layers, and the material creep characteristics. Laplace's law has been applied to compression therapy.