Physiological Status Monitoring Research Articles

Electrical Impedance Tomography for Biomedical Applications: Circuits and Systems Review

There has been considerable interest in electrical impedance tomography (EIT) to provide low-cost, radiation-free, real-time and wearable means for physiological status monitoring. To be competitive with other well-established imaging modalities, it is important to understand the requirements of the specific application and determine a suitable system design. This paper presents an overview of EIT circuits and systems including architectures, current drivers, analog front-end and demodulation circuits, with emphasis on integrated circuit implementations. Commonly used circuit topologies are detailed, and tradeoffs are discussed to aid in choosing an appropriate design based on the application and system priorities. The paper also describes a number of integrated EIT systems for biomedical applications, as well as discussing current challenges and possible future directions.

On the intersection of molecular bioelectronics and biosensors: 20 Years of C3B

Formed in 2000 at Virginia Commonwealth University, the Center for Bioelectronics, Biosensors and Biochips (C3B®) has subsequently been located at Clemson University and at Texas A&M University. Established as an industry-university collaborative center of excellence, the C3B has contributed new knowledge and technology in the areas of i) molecular bioelectronics, ii) responsive polymers, iii) multiplexed biosensor systems, and iv) bioelectronic biosensors. Noteworthy contributions in these areas include i) being the first to report direct electron transfer of oxidoreductase enzymes enabled by single walled carbon nanotubes and colloidal clays, ii) the molecular level integration of inherently conductive polymers with bioactive hydrogels using bi-functional monomers such as poly(pyrrole-co-3-pyrrolylbutyrate-conj-aminoethylmethacrylate) [PyBA-conj-AEMA] and 3-(1-ethyl methacryloylate)aniline to yield hetero-ladder electroconductive hydrogels, iii) the development of a multi-analyte physiological status monitoring biochip, and iv) the development of a bioanalytical Wien-bridge oscillator for the fused measurement to lactate and glucose. The present review takes a critical look of these contributions over the past 20 years and offers some perspective on the future of bioelectronics-based biosensors and systems. Particular attention is given to multiplexed biosensor systems and data fusion for rapid decision making.

Comparative Physiological and Proteomic Analysis Reveals Different Involvement of Proteins during Artificial Aging of Siberian Wildrye Seeds.

Seed aging has an important effect on the germplasm preservation and industrialized production of Siberian wildrye (Elymus sibiricus) in the Qinghai-Tibet Plateau. However, so far its underlying molecular mechanisms still largely remain unknown. To shed light on this topic, one-year stored seeds of E. sibiricus were exposed to artificial aging treatments (AAT), followed by seed vigor characteristics and physiological status monitoring. Then global proteomics analysis was undertaken by the tandem mass tags (TMT) technique, and the proteins were quantified with liquid chromatography-tandem mass spectrometry on three aging time points (0 h, 36 h and 72 h). Finally, we verified the expression of related proteins by parallel reaction monitoring (PRM). Our results demonstrated that the seed vigor decreased remarkably in response to artificial aging, but the relative ion-leakage and malondialdehyde content, superoxide anion and hydrogen peroxide showed the opposite situation. Proteomic results showed that a total of 4169 proteins were identified and quantified. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that a series of key pathways including carbohydrate metabolism, lipid metabolism, and antioxidant activity were severely damaged by aging treatments. Numerous key proteins such as glyceraldehyde triphosphate glyceraldehyde dehydrogenase, succinate dehydrogenase, lipoxygenase, peroxidase, glutathione-s-transferase and late embryogenesis abundant proteins were significantly down-regulated. However, the up-regulation of the heat shock protein family has made a positive contribution to oxidative stress resistance in seeds. This study provides a useful catalog of the E. sibiricus proteomes with insights into the future genetic improvement of seed storability.

GO film on flexible substrate: An approach to wearable colorimetric humidity sensor

Graphene and graphene oxides have outstanding electrical and optical properties, making it particularly interesting in the field of gas sensing. In this study, colorimetric humidity sensor based on graphene oxide (GO) thin film on different substrates was fabricated by using dip coating technique. The fabrication conditions that influence the humidity response were systematically investigated and optimized. Our results indicated that GO thin film on metallized polyethylene terephthalate (mPET) film displayed poor resolution and sensitivity if it was fabricated from aqueous dispersion. However, both spectra resolution and reflectance color of GO film on mPET are enhanced, if it was fabricated from acetone dispersion. It was attributed to the wetting property of solvent that help to form uniform d-spacing of GO sheet assemblies as revealed from XRD analysis. Bending test of the formed GO film on mPET showed an extreme spectra stability upon 10,000 cycles of bending, suggesting that the devices are quite suitable for flexible device applications in both personal physiological condition monitoring and environment condition change detection.

National Early Warning Score Parameters at the Emergency Department as In Hospital Cardiac Arrest Predictors

In Hospital Cardiac Arrest (IHCA) is fairly common occurrence, although it can be prevented. Physiological status monitoring at Emergency Departement (ED) is crucial for early detection of potential IHCA incidence. National Early Warning Score (NEWS) is a scoring system to assess deterioration of patient's condition, but it is not yet known which parameters that have predictive value for IHCA incidence. Examine NEWS parameters of the patients while at the ED that have predictive value of IHCA incidence. This study was conducted retrospectively on inpatient medical records. The NEWS parameters examined were respiration rate score, oxygen saturation score, body temperature score, systolic blood pressure score, pulse rate score and level of consciousness score. Logistic regression analysis was used to test the predictive ability of NEWS parameters. Total score NEWS proved to be correlated with IHCA incidence (p=0.000; r=0.434). Parameters that have predictive value are systolic blood pressure score (p=0.001; OR=14.730), respiration rate score (p=0.000; OR=14.483) and level of consciousness score (p=0.000; OR=6.920). The NEWS parameter when the patients will be transferred from ED to the wards that have predictive value for IHCA incidence are systolic blood pressure score, respiration rate score and level of consciousness score.

Noninvasive inferring expressed genes and in vivo monitoring of the physiology and pathology of pregnancy using cell-free DNA

Noninvasive monitoring of fetal development and the early detection of pregnancy-associated complications is challenging, largely because of the lack of information about the molecular spectrum during pregnancy. Recently, cell-free DNA in plasma was found to reflect the global nucleosome footprint and status of gene expression and showed potential for noninvasive health monitoring during pregnancy. We aimed to test the relationships between plasma cell-free DNA profiles and pregnancy biology and evaluate the use of a cell-free DNA profile as a noninvasive method for physiological and pathologic status monitoring during pregnancy. We used genome cell-free DNA sequencing data generated from noninvasive prenatal testing in a total of 2937 pregnant women. For each physiological and pathologic condition, features of the cell-free DNA profile were identified using the discovery cohort, and support vector machine classifiers were built and evaluated using independent training and validation cohorts. We established nucleosome occupancy profiles at transcription start sites in different gestational trimesters, demonstrated the relationships between gene expression and cell-free DNA coverage at transcription start sites, and showed that the cell-free DNA profiles at transcription start sites represented the biological processes of pregnancy. In addition, using cell-free DNA data, nucleosome profiles of transcription factor binding sites were identified to reflect the transcription factor footprint, which may help to reveal the molecular mechanisms underlying pregnancy. Finally, by using machine-learning models on low-coverage noninvasive prenatal testing data, we evaluated the use of cell-free DNA nucleosome profiles for distinguishing gestational trimesters, fetal sex, and fetal trisomy 21 and highlighted its potential utility for predicting physiological and pathologic fetal conditions by using low-coverage noninvasive prenatal testing data. Our analyses profiled nucleosome footprints and regulatory networks during pregnancy and established a noninvasive proof-of-principle methodology for health monitoring during pregnancy.

Noble metal alloy nanoparticles coated flexible MoS2 paper for the determination of reactive oxygen species

The monitoring of reactive oxygen species (ROS) in biological system has been occupying research hotspots recently, since the biochemical alterations caused by the overproduction of ROS are the main incentives of diseases and accelerated aging process. In this work, we proposed an effective and simple strategy for the construction of high-performance ROS electrochemical sensor. Noble metal alloy nanoparticles (AuPt nanoparticles) with high catalytic activity were spontaneously coated on the freestanding metallic molybdenum disulfide (MoS2) paper independent of any auxiliary conditions. Results have found that the abundant defects and electrons distributed on the metallic MoS2 paper could provide active sites for the nucleation and growth of noble metal nanoparticles. Besides, the excellent mechanical properties of the MoS2 paper promote the formation of flexible sensors. The fabricated MoS2 paper-based sensor was demonstrated to detect ROS with the advantages of wide linear range, prominent selectivity and flexibility, satisfactory detection stability, as well as simple and convenient preparation process. Furthermore, the desirable results obtained in the real sample experiments operated in plant extract pave the way for further real-time monitoring of plant physiological status to provide valuable information for guidance during plant growth.

Advances in Sweat Wearables: Sample Extraction, Real-Time Biosensing, and Flexible Platforms.

Wearable biosensors for sweat-based analysis are gaining wide attention due to their potential use in personal health monitoring. Flexible wearable devices enable sweat analysis at the molecular level, facilitating noninvasive monitoring of physiological states via real-time monitoring of chemical biomarkers. Advances in sweat extraction technology, real-time biosensors, stretchable materials, device integration, and wireless digital technologies have led to the development of wearable sweat-biosensing devices that are light, flexible, comfortable, aesthetic, affordable, and informative. Herein, we summarize recent advances of sweat wearables from the aspects of sweat extraction, fabrication of stretchable biomaterials, and design of biosensing modules to enable continuous biochemical monitoring, which are essential for a biosensing device. Key chemical components of sweat, sweat capture methodologies, and considerations of flexible substrates for integrating real-time biosensors with electronics to bring innovations in the art of wearables are elaborated. The strategies and challenges involved in improving the wearable biosensing performance and the perspectives for designing sweat-based wearable biosensing devices are discussed.

Wearable Battery-Free Perspiration Analyzing Sites Based on Sweat Flowing on ZnO Nanoarrays

HighlightsWearable battery-free perspiration analyzing sites based on sweat flowing on ZnO nanoarrays was fabricated.Coupling of hydrovoltaic effect and enzymatic reaction were analyzed.The wearable wireless physiological status monitoring system has potential application in constructing sports big data.

The Development of Early Warning Systems for Home/Community Elderly Care

With Taiwan now an "aged society", home safety for older individuals has become a very important issue. The purpose of establishing early warning systems in homes and/or communities is to generate and disseminate meaningful warning information to medical institutions or rescue units in a timely manner so that they may take timely and appropriate action. The main purpose of this paper is to introduce the current application of information and communication technology (ICT, especially the Internet of Things and artificial intelligence) in early warning systems for home and community care. Two approaches to developing these systems are introduced: instant detection and prevention monitoring. Instant detection facilitates fall detection and personnel tracking, while the focus of prevention monitoring is on preventing falls and physiological status monitoring. The challenges faced by in incorporating ICT into these early monitoring systems are discussed as well.

Highly sensitive pressure sensor based on structurally modified tissue paper for human physiological activity monitoring

ABSTRACTPressure sensor has become an important part of physiological condition monitoring system because it can respond to small pressure in human activities. Tissue paper has been studied as a carrier of sensitive unit layer for pressure sensors in recent years due to its internal pore structure and wrinkle morphology of surface. In this work, the pore structure of the tissue paper is improved by the principle of hydration and destruction of hydrogen bonds. Based on flexible substrate of NaOH modified tissue paper (NMTP) with enhanced pore structure, combined with dip‐coating composite conductive filler, the pressure sensor is fabricated by sandwiching the sensitive unit between the interdigital electrode and the microdome elastomer through layer‐by‐layer assembly method. Thanks to the excellent interfacial resistance effect of porous NMTP under pressure, the sensitivity of NMTP‐based pressure sensor is as high as 37.5 kPa−1 in a pressure range of 0–2 kPa. Finally, the follow‐up studies on pressure sensors have been proven to be applicable to a variety of physiological activity such as pulse detection, respiration detection and voice recognition. The NMTP‐based sensitive unit provides alternative strategy to improve performance of pressure sensors and extends potential applications in monitoring human physiological activities. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48973.

Capabilities of an Assessment System for Construction Worker Physiology

AbstractLimited data exists on how construction activities physically impact construction workers. This research explores the use of physiological status monitors (PSMs) to assess the impact of con...

Створення історичного контролю біохімічних показників сироватки крові щурів WISTAR HANNOVER

ABSTRACT. Objective. Creation of historical control of certain serum biochemistry parameters of Wistar Hannover rats. Materials and methods. The data were obtained from 1,180 Wistar Hannover rats of the control groups that were kept in conventional vivarium during the period from 2013 to 2018 in the toxicological studies conducted as per GLP. Eight serum biochemistry parameters: alkaline phosphatase, aspartate transaminase, alanine transaminase, total protein, urea, cholesterol, triglycerides, glucose were determined in rats. Biochemistry parameters were determined using open type biochemical analyser Vitalab Flexor E (The Netherlands) with reagents manufactured by Global Scientific (USA) and BioSystems (Spain). Results. The obtained data were analysed by age and gender of biological models. The average values and standard deviations for each parameter were determined during the creation of historical control. Minimal and maximal values and normal ranges were established for each parameter. Changes in historical control were reviewed by year. Conclusion. Created historical control can be used for an objective interpretation of obtained serum biochemistry parameters in toxicological studies as well as for assessment and monitoring of physiological conditions of laboratory rats. Keywords: serum, biochemistry parameters, historical control, Wistar Hannover rats.

Development of thermography methodology for early diagnosis of fungal infection in table grapes: The case of Aspergillus carbonarius

Traditional diagnostic methods employed in food mycology are based on macroscopic and microscopic characteristics and culture in appropriate media. The macroscopic methods exhibit limitations in detecting fungal development before the fruiting structures become evident. One of the imaging techniques, which have attracted attention, is infrared thermography which has been used in non-destructive monitoring of physiological status of plants. The filamentous fungus Aspergillus carbonarius is the causal pathogen of sour rot of grapes and produces ochratoxin-A, the most important mycotoxin in grapes. Ochratoxin-A has been shown to be nephrotoxic, hepatotoxic, teratogenic and immunosuppressive properties with a tremendous impact on human health. In order to assess the spatial temperature heterogeneity in A. carbonarius infected table grapes, the average temperature of the berries surface as well as the maximum temperature difference between the infected and non-infected areas of berries’ surface were calculated. The average grape temperature during the development of the fungal mycelium in the berry was significantly lower than that of the healthy one, while the maximum temperature difference increased during the fungal colonization compared to the healthy grapes that stayed constant. The estimated shape factors derived by fitting the temperature data of the thermal images to the Weibull distribution was able to identify healthy from infected berry areas even during the very early stages of A. carbonarius infection.

Smart Pleural Effusion Drainage Monitoring System Establishment for Rapid Effusion Volume Estimation and Safety Confirmation

Pleural effusion is the pathologic accumulation of body fluids around the unilateral or bilateral lungs that is primarily caused by heart disease. A chest radiograph is a rapid examination technique used to provide a preliminary diagnosis of lung and heart diseases. Computer-aided diagnosis with the digitalized image is an automated approach that addresses the drawbacks of manual inspection. In this study, two corner detectors along with a two-dimensional convolution process are used to enhance the chest X-ray image for an accurate extrapolation of the bilateral lung cavities. Based on bounding box pixel analysis, the pixel ratios of the lung anatomy between normal and abnormal conditions can be estimated to identify the pleural effusion size. Next, a smart drainage monitoring system is developed to improve the current functions of the traditional drainage tool and confirm the drainage safety, including (a) drainage volume and required time detection, (b) unplanned removal warning, and (c) physiological status monitoring. The experimental result will be used to determine the feasibility of the proposed effusion volume estimation algorithm and the efficiency of the smart drainage monitoring prototyping tool. The proposed smart drainage monitoring system and the computer-aided method with digitalized images can be further applied in real clinical practice in the intensive care unit.

In Vivo Phenotyping for the Early Detection of Drought Stress in Tomato.

Drought stress imposes a major constraint over a crop yield and can be expected to grow in importance if the climate change predicted comes about. Improved methods are needed to facilitate crop management via the prompt detection of the onset of stress. Here, we report the use of an in vivo OECT (organic electrochemical transistor) sensor, termed as bioristor, in the context of the drought response of the tomato plant. The device was integrated within the plant's stem, thereby allowing for the continuous monitoring of the plant's physiological status throughout its life cycle. Bioristor was able to detect changes of ion concentration in the sap upon drought, in particular, those dissolved and transported through the transpiration stream, thus efficiently detecting the occurrence of drought stress immediately after the priming of the defence responses. The bioristor's acquired data were coupled with those obtained in a high-throughput phenotyping platform revealing the extreme complementarity of these methods to investigate the mechanisms triggered by the plant during the drought stress event.

Materials and Designs for Power Supply Systems in Skin-Interfaced Electronics

Recent advances in materials chemistry and composite materials design establish the foundations for classes of electronics with physical form factors that bridge the gap between soft biological organisms and rigid microsystems technologies. Skin-interfaced platforms of this type have broad utility in continuous clinical-grade monitoring of physiological status, with the potential to significantly lower the cost and increase the efficacy of modern health care. Development of materials and device designs for power supply systems in this context is critically important, and it represents a rapidly expanding focus of research in the chemical sciences. Reformulating conventional technologies into biocompatible platforms and co-integrating them into skin-interfaced systems demand innovative approaches in materials chemistry and engineering. In terms of physical properties, the resulting devices must offer levels of flexibility, stretchability, thickness, and mass density that approach those of the epidermis itself, while maintaining operational characteristics and mechanical durability for practical use outside of a laboratory or hospital. While nearly all commercially available components for energy storage and harvesting are rigid and planar, recent research provides options in devices that are biocompatible not only at the level of the constituent materials but also in terms of the mechanics and geometrical forms, with resulting capabilities for establishing stable, nonirritating, intimate interfaces to the skin for extended periods of time. This Account highlights the range of materials choices and associated device architectures for skin-interfaced power supply systems. The Account begins with an overview of the main design strategies, ranging from one-, two-, and three-dimensional engineered composite structures to active materials that are intrinsically stretchable. The following sections describe a broad collection of devices based on these concepts, starting with batteries and supercapacitors for storage and then photovoltaic, piezoelectric, triboelectric, and thermoelectric devices for harvesting. Representative examples highlight recent advances, with a focus on the relationship between the materials and the performance during deformation. A final section discusses the challenges and opportunities in this area. Continued efforts in fundamental chemical research will be critically important to progress in this emerging field of technology. For example, understanding the mechanisms by which physical deformations affect the intrinsic materials properties and the system-level performance requires further study. The development of stretchable and biocompatible solid electrolytes with high ionic conductivity is an example of a specific area of interest for energy storage devices. Here and in other storage and harvesting systems advanced materials are needed to provide robust barriers to environmental factors. Work to address these and other interesting challenges will demand multidisciplinary collaborations between chemists, materials scientists, bioengineers, and clinicians, all oriented toward establishing the foundations for technologies that could help to address global grand challenges in human health care.

Automated in Vivo Nanosensing of Breath-Borne Protein Biomarkers.

Toxicology and bedside medical condition monitoring is often desired to be both ultrasensitive and noninvasive. However, current biomarker analyses for these purposes are mostly offline and fail to detect low marker quantities. Here, we report a system called dLABer (detection of living animal's exhaled breath biomarker) that integrates living rats, breath sampling, microfluidics, and biosensors for the automated tracking of breath-borne biomarkers. Our data show that dLABer could selectively detect (online) and report differences (of up to 103-fold) in the levels of inflammation agent interleukin-6 (IL-6) exhaled by rats injected with different ambient particulate matter (PM). The dLABer system was further shown to have an up to 104 higher signal-to-noise ratio than that of the enzyme-linked immunosorbent assay (ELISA) when analyzing the same breath samples. In addition, both blood-borne IL-6 levels analyzed via ELISA in rats injected with different PM extracts and PM toxicity determined by a dithiothreitol (DTT) assay agreed well with those determined by the dLABer system. Video recordings further verified that rats exposed to PM with higher toxicity (according to a DTT assay and as revealed by dLABer) appeared to be less physically active. All the data presented here suggest that the dLABer system is capable of real-time, noninvasive monitoring of breath-borne biomarkers with ultrasensitivity. The dLABer system is expected to revolutionize pollutant health effect studies and bedside disease diagnosis as well as physiological condition monitoring at the single-protein level.

Military applications of soldier physiological monitoring

Wearable physiological status monitoring is part of modern precision medicine that permits predictions about an individual’s health and performance from their real-time physiological status (RT-PSM) instead of relying on population-based predictions informed by estimated human, mission, and environmental/ambient conditions. RT-PSM systems have useful military applications if they are soldier-acceptable and provide important actionable information. Most commercially available systems do not address relevant military needs, typically lack the validated algorithms that make real time computed information useful, and are not open architected to be integrated with the soldier technological ecology. Military RT-PSM development requires committed investments in iterative efforts involving physiologists, biomedical engineers, and the soldier users. Military operational applications include: (1) technological enhancement of performance by providing individual status information to optimize self-regulation, workload distribution, and enhanced team sensing/situational awareness; (2) detection of impending soldier failure from stress load (physical, psychological, and environmental); (3) earliest possible detection of threat agent exposure that includes the “human sensor”; (4) casualty detection, triage, and early clinical management; (5) optimization of individual health and fitness readiness habits; and (6) long term health risk-associated exposure monitoring and dosimetry. This paper is focused on the performance-related applications and considers near term predictions such as thermal-work limits, alertness and fitness for duty status, musculoskeletal fatigue limits, neuropsychological status, and mission-specific physiological status. Each new measurement capability has provided insights into soldier physiology and advances the cycle of invention, lab and field testing, new discovery and redesign.

International consensus on military research priorities and gaps — Survey results from the 4th International Congress on Soldiers’ Physical Performance

ObjectivesThe objectives of this study were to identify perceived priorities related to military personnel’s health and physical performance, among attendees at the 4th International Congress on Soldiers’ Physical Performance (ICSPP), and to determine if perceived priorities had changed between the 3rd ICSPP survey held in 2014 and the 4th ICSPP survey held in 2017. DesignElectronic survey. MethodsRespondents were asked to grade priority areas on a Likert scale, and average ratings were used to rank priority areas. Responses to free text questions were analyzed qualitatively. Responses to the 4th ICSPP survey were described and compared to responses to the 3rd ICSPP survey. ResultsThe 4th ICSPP survey respondents were a diverse group (40.6% military, 58.9% civilian). The two most important priority areas identified were physical demands in operational environments (mean score=4.41/5) and measuring physical performance/fitness (4.38/5), which were also the top two areas in the 3rd ICSPP survey. There was remarkable overlap in the rankings of priority areas between the two surveys. Sleep and nutrition were emerging priority areas and were perceived as relatively more important in the 4th ICSPP survey compared to the 3rd ICSPP survey. The greatest perceived emerging threat was resilience/psychological fitness of recruits (4.16/5). Physiological status monitoring (2.79/4) was identified as the most important technology. ConclusionsDespite the diverse backgrounds of the respondents, there was a clear continuing consensus about perceived important priority areas influencing military personnel’s health and physical performance. Soldier resiliency and assessment of physiological status were research topics identified as top priorities.