Ingestible Pill Research Articles

Reliability of Wearable Technology to Monitor Core Temperature Among Helicopter-Based EMS Crews.

Excessive heat stress led to more than 400 deaths in the United States from 2011 to 2021. Common methods for heat injury prevention revolve around measurements of the environment and fail to account for the unique individual response to stressors. An observational approach was utilized with nine helicopter-based emergency medical services personnel during emergency flights to compare core temperature readings obtained from an ingestible temperature monitoring pill and the estimated core temperature reading of the Slate Safety Band V2 wearable device. Comparison of data was conducted within Microsoft Excel programming to determine the mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), mean biased error (MBE), and Bland-Altman plot development. A significant bias (t = 17.58, p < .001) toward the Slate Safety device reading higher with an average difference of -0.48°C (-0.86°F) was found, meaning the average temperature reading is 0.48°C (-0.86°F) higher with the Slate Safety device. A significant correlation of .26 (p < .001) was noted between the ingestible pill and the wearable device with a 95% confidence interval of 0.23 to 0.29. Aggregate core temperature data demonstrated an MSE of 0.43, an RMSE of 0.65, an MAE of 0.54, and an MBE of -0.48. The ability to monitor the physiological parameters of a worker remotely adds safety tools relative to the risks of heat stress. The slightly higher reading associated with the Slate Safety wearable device provides an added safety margin to protect our workers.

Ingestible Sensor Based on Fluorescent Gold Nanoparticles and Molecularly Imprinted Polymers on Thread for Localized Quantification of Escherichia Coli in the Gastrointestinal Tract

AbstractThe small intestinal (SI) microbiota plays an important role in human health and disease. Current methods based on fecal analysis do not provide an accurate representation of the SI microbiome. This article introduces an ingestible sensor for the quantification of Escherichia coli (E. coli) in the SI by developing the fluorescent thread‐based ingestible pill analytical device (TPAD) using fluorescent gold nanoclusters (AuNCs) coupled with molecularly imprinted polymers (MIPs). Quantitative detection lies in the change in fluorescence signal on thread as proportional to target bacteria concentrations using a smartphone. Utilizing a pH‐sensitive enteric coating, this device facilitates localized sampling of the SI microbiome. Hydrophilic beads are employed to autonomously seal the device after sampling, offering a self‐locking mechanism. The sensor demonstrates a linear range for E. coli detection between 2.0 × 103 and 14.0 × 103 CFU mL−1 with an R2 of 0.9975 and a detection limit (LOD) of 400.0 × 102 CFU mL−1. The sensor also shows remarkable precision and acceptable accuracy for monitoring E. coli levels in in vivo animal studies compared to commercially available test kits. The developed TPAD, therefore, offers a novel, low‐cost, and non‐invasive method for rapidly diagnosing gastrointestinal (GI)‐related medical conditions and studying host–microbiome interactions.

Magnetically Activated Ingestible Pill with Archimedes Screw for On‐Demand Sampling of Intestinal Microbiome

AbstractTechnologies capable of noninvasively sampling different locations in the gut upstream of the colon will enable new insights into the role of organ‐specific microbiomes on human health. Herein, an ingestible pill for the sampling of gut lumen based on one of the earliest hydraulic machines known as an Archimedes screw is reported. The design contains twisted wires as Archimedes screw driven by a motor, wirelessly activated using a magnet. The sampling performance of the screw‐pump pill is characterized using realistic in vitro models and validated in vitro using E. coli expressing different fluorescent proteins. The use of the Archimedes screw enables the pill to sample the dense GI environment. The pill is also tested ex vivo in the pig intestine and in vivo in pigs. Herein, the results show that the bacterial populations recovered from the pill's chamber closely resemble the targeted bacterial population of the microenvironment to which the pill is exposed. Such ingestible devices have the potential to revolutionize the understanding of the spatial diversity of the gut microbiome and its response to medical conditions and treatments.

Assessing core body temperature in a cool marathon using two pill ingestion strategies

Abstract Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool, ambient conditions using a two-pill ingestion strategy. Methods Thirty-two recreational runners (age: 38.7 ± 10.2 years, mass: 73.9 ± 11.0 kg, height: 177 ± 8 cm) were invited to participate in this study. Core temperature was continuously assessed using telemetric ingestible pills. Each runner swallowed two pills: the first pill (Pill 1) 11 h:47 min ± 1 h:01 min pre-race (before overnight sleep) and the second (Pill 2) 2 h:35 min ± 0 h:54 min pre-race (on wakening). Results Pre-race core temperature for Pill 1 was significantly different from Pill 2, with values of 37.4 ± 0.4 °C and 37.1 ± 0.6 °C, respectively (p=0.006). The mean core temperature during the race was higher for Pill 1 compared to Pill 2 (38.5 ± 0.5 °C and 37.8 ± 1.0 °C, respectively; p&lt;0.001). Peak core temperature was higher for Pill 1 compared to Pill 2 (39.1 ± 0.5 °C and 38.8 ± 0.5 °C, respectively; p=0.03). Post-race core temperature was higher for Pill 1 compared to Pill 2 (38.8 ± 0.7 °C and 38.1 ± 1.3 °C, respectively; p=0.02). Conclusions The timing of pill ingestion significantly impacted core temperature and hence timing of pill ingestion should be standardised (5 h:30 min–7 h prior to measurement). Despite the relatively cool ambient conditions during the race, a significant number of runners achieved a high core body temperature (≥39 °C), which was not accompanied by any signs of heat illness.

Head and neck cooling enhance exercise tolerance in individuals with multiple sclerosis

BackgroundIndividuals with Multiple Sclerosis (MS) experience impairments in heat dissipation, compromising core temperature regulation during exercise. ObjectiveTo examine the efficacy of combined head-and-neck cooling as administered via a commercially available cooling cap and neck wrap in mitigating increases in core temperature during exercise. MethodsOn separate days, ten (7 females) adults (46.1 ± 11.6 years) with relapsing-remitting MS performed semi-recumbent cycling consisting of an incremental exercise bout to volitional fatigue in a temperate environment (23 °C, 50 % relative humidity) while undergoing head-and-neck cooling using a cooling cap and neck wrap maintained at 10 °C (COLD) or 24–26 °C (NEUTRAL). Prior to and following a 30-minute post-exercise recovery, functional capacity was assessed by a battery of tests consisting of a 2-minute walk test, Timed 25-Foot Walk test, sit-to-stand test, and Berg Balance Scale. Core (ingestible pill) and skin temperatures were recorded continuously. The level of fatigue was measured with questionnaires. ResultsThe duration of the incremental exercise test increased with the application of COLD (28.4 ± 5.1 min) versus NEUTRAL water (vs 20.8 ± 5.1 min) (p = 0.001) and was paralleled by a significant reduction in body temperatures (∼1 °C, p < 0.05). The distance covered during the 2-min walk test performed after the incremental exercise test increased with the COLD (176.5 ± 0.6 m), relative to the NEUTRAL condition (147.7 ± 43.5 m) (p = 0.01). Fatigue levels did not change between conditions. ConclusionWe show that head-and-neck cooling with cold water effectively enhances exercise tolerance and mitigates increases in core temperature during exercise in individuals with MS.

Ingestible pills reveal gastric correlates of emotions.

Although it is generally held that gastrointestinal (GI) signals are related to emotions, direct evidence for such a link is currently lacking. One of the reasons why the internal milieu of the GI system is poorly investigated is because visceral organs are difficult to access and monitor. To directly measure the influence of endoluminal markers of GI activity on the emotional experience, we asked a group of healthy male participants to ingest a pill that measured pH, pressure, and temperature of their GI tract while they watched video clips that consistently induced disgust, fear, happiness, sadness, or a control neutral state. In addition to the objective physiological markers of GI activity, subjective ratings of perceived emotions and visceral (i.e. gastric, respiratory and cardiac) sensations were recorded, as well as changes in heart rate (HR), heart rate variability (HRV) and spontaneous eyes blinks as non-gastric behavioral and autonomic markers of the emotional experience. We found that when participants observed fearful and disgusting video clips, they reported to perceive not only cardiac and respiratory sensations but also gastric sensations, such as nausea. Moreover, we found that there was a clear relation between the physiology of the stomach and the perceived emotions. Specifically, when disgusting video clips were displayed, the more acidic the pH, the more participants reported feelings of disgust and fear; the less acidic the pH, the more they reported happiness. Complementing the results found in the deep gastric realm, we found that disgusting stimuli induced a significant increase in HRV compared to the neutral scenarios, and together with fearful video clips a decrease in HR. Our findings suggest that gastric signals contribute to unique emotional states and that ingestible pills may open new avenues for exploring the deep-body physiology of emotions.

Controlling and powering a fully implantable artificial pancreas refillable by ingestible pills.

Over the past decade, there has been a growing interest in the development of an artificial pancreas for intraperitoneal insulin delivery. Intraperitoneal implantable pumps guarantee more physiological glycemic control than subcutaneous wearable ones, for the treatment of type 1 diabetes. In this work, a fully implantable artificial pancreas refillable by ingestible pills is presented. In particular, solutions enabling the communication between the implanted pump and external user interfaces and novel control algorithms to intraperitoneally release an adequate amount of insulin based on glycemic data are shown. In addition, the powering and the wireless battery recharging are addressed. Specifically, the design and optimization of a customized transcutaneous energy transfer with two independent wireless channels are presented. The system was tested in terms of recharging efficacy, possible temperature rise within the body, during the recharging process and reliability of the wireless connection in the air and in the presence of ex vivo tissues.Clinical Relevance- This work aims to improve the control, battery recharging, and wireless communication of a fully implantable artificial pancreas for type 1 diabetes treatment.

An Ingestible Pill With CMOS Fluorescence Sensor Array, Bi-Directional Wireless Interface and Packaged Optics for in-Vivo Bio-Molecular Sensing.

The article presents for the first time a pill-based ingestible electronics with CMOS integrated multiplexed fluorescence bio-molecular sensor arrays, bi-directional wireless communication and packaged optics in a FDA-approved capsule for in-vivo bio-molecular sensing. The silicon chip integrates both the sensor array, and the ultra-low-power (ULP) wireless system that allows offloading sensor computing to an external base station that can reconfigure the sensor measurement time, and its dynamic range, allowing optimized high sensitivity measurement under low power consumption. The integrated receiver achieves -59 dBm receiver sensitivity dissipating 121 µW of power. The integrated transmitter operates in a dual mode FSK/OOK delivering -15 dBm of power. The 15-pixel fluorescence sensor array follows an electronic-optic co-design methodology and integrates the nano-optical filters with integrated sub-wavelength metal layers that achieves high extinction ratio (39 dB), thereby eliminating the need for bulky external optical filters. The chip integrates photo-detection circuitry and on-chip 10-bit digitation, and achieves measured sensitivity of 1.6 attomoles of fluorescence labels on surface, and between 100 pM to 1 nM of target DNA detection limit per pixel. The complete package includes a CMOS fluorescent sensor chip with integrated filter, a prototyped UV LED and optical waveguide, functionalized bioslip, off-chip power management and Tx/Rx antenna that fits in a standard FDA approved capsule size 000.

Comparison of Slate Safety Wearable Device to Ingestible Pill and Wearable Heart Rate Monitor.

With the increase in concern for deaths and illness related to the increase in temperature globally, there is a growing need for real-time monitoring of workers for heat stress indicators. The purpose of this study was to determine the usability of the Slate Safety (SS) wearable physiological monitoring system. Twenty nurses performed a common task in a moderate or hot environment while wearing the SS device, the Polar 10 monitor, and having taken the e-Celsius ingestible pill. Data from each device was compared for correlation and accuracy. High correlation was determined between the SS wearable device and the Polar 10 system (0.926) and the ingestible pill (0.595). The SS was comfortable to wear and easily monitored multiple participants from a distance. The Slate Safety wearable device demonstrated accuracy in measuring core temperature and heart rate while not restricting the motion of the worker, and provided a remote monitoring platform for physiological parameters.

Design and Implementation of a Low Power Wireless Frequency-Division Multiplexed Magnetic 3D Localization Scheme With Sub-mm Precision for Capsule Endoscopy Applications

This letter presents a new magnetic localization scheme based on frequency-division multiplexing for capsule endoscopy applications. The approach significantly reduces the reference excitation coil sizes and decreases the required excitation current by three orders of magnitude compared to prior work, making it practical for wearable systems. Different spatial configurations of the reference coils are considered and simulated to provide design insight for maximizing localization accuracy. A fully integrated wireless receiver prototype is implemented in 180-nm bulk CMOS and packaged in an ingestible pill form factor. To the best of our knowledge, the new scheme achieves the best experimentally demonstrated tracking accuracy in both 2D and 3D localization experiments, achieving a sub-mm mean absolute position error and consuming only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$336~\mu \text{W}$ </tex-math></inline-formula> while running at 100% duty cycle.

Association between thermal responses, medical events, performance, heat acclimation and health status in male and female elite athletes during the 2019 Doha World Athletics Championships

PurposeTo determine associations between thermal responses, medical events, performance, heat acclimation and health status during a World Athletics Championships in hot-humid conditions.MethodsFrom 305 marathon and race-walk starters, 83 completed a...

An Intelligent Wired Capsule for the Treatment of Helicobacter pylori

An endoscopic capsule is a miniaturized ingestible video camera used to acquire images of the gastrointestinal tract wirelessly. Being morphologically equivalent to any ingestible pill, they can be simply swallowed. Endoscopic capsules therefore present an inviting alternative to the traditional endoscope for the examination of the gastrointestinal tract as well for therapeutic purposes. Endoscopic capsules are considered a disruptive technology, as they have revolutionized the examination of the gastrointestinal tract in a relatively short time. The implementation of an active locomotion system can improve the performance of a capsule and, in the solution proposed in this paper, allows providing the capsule the needed power for therapeutic purposes. Alternative therapeutic solutions, based on optical solutions and capsule endoscopy can be applied to patients affected by Helicobacter pylori, a bacterium of the stomach that affects about half of the world population, mainly in developing countries. The infection can be asymptomatic or associated with slight symptomatology. In some cases, it can take to major pathologies or death. The literature reports results deriving from recent applications of photodynamic treatments to H. pylori. Specific wavelengths have been found to exhibit photo-killing capabilities toward the bacterium. Some solutions have been proposed based on the use of endoscopic devices and capsules capable of administering photodynamic therapy inside the stomach. The proposed treatments, however, are invasive and insufficient to achieve long-term eradication. In this work, the administration of photodynamic therapy is proposed, aimed at the eradication of H. pylori by means of an active endoscopic capsule with LED emission. The capsule design, in addition to the therapeutic module aimed at administering an appropriate light intensity at specific wavelengths already demonstrated in the literature, integrates an active locomotion system aimed at maximizing the efficiency of the treatment.

A Review on State of Art Techniques of Antennas for Body Area Networks

In this paper, we explore some of the notable research works that will open a new dimension in the field of antenna research applicable to body area networks. Different types of antennas for body area networks include implantable antenna, ingestible pill antenna, and wearable antennas. The antennas for body area networks gained the attention of the researchers after the demands of the compact as well as efficient wearable devices increased. The design of antennas for body area network applications is very interesting and challenging, as a researcher has to ensure that the antenna should have a small footprint, and be flexible. Simultaneously, the radiation must be in a particular direction with a workable gain, and low Specific Absorption Rate (SAR) to avoid damage. These antennas require performing well in proximity to the living bodies that tend to degrade the performance. The antennas that are in demand include implantable antennas, ingestible antennas, on-body antennas, and antennas for off-body communications. In this paper, the earlier works have been analyzed well and verified with a compact CPW-fed circular patch antenna design, backed by a metal conductor. This antenna exhibits the perfect matching at two frequency bands. These are S11 (below -10 dB) bandwidth of 3.4 GHz ranging from 2.45 – 5.89 GHz and an S11 bandwidth of 0.99 GHz ranging from 9.10 – 10.09 GHz. While in contact with the human body, the antenna exhibits a bandwidth of 2.54 GHz between 3.02-5.56 GHz and a bandwidth of 3.01 GHz between 9.8-12.81 GHz. The SAR values are 0.82 W/kg and 0.56 W/kg. The antenna is a suitable candidate for off-body communication in wearable applications.

Physiological Strain And Heat Storage In Different Hot Conditions Of Equivalent Wet Bulb Globe Temperature

Varying levels of ambient temperature and humidity differently affect heat storage (S) during walking, but the quantification of S at equivalent wet bulb globe temperature (WBGT) and affects on physiological strain have yet to be determined. PURPOSE: This investigation tested the hypothesis that varying hot environments of equal WBGT result in similar cumulative S but differing levels of cardiovascular strain and ventilatory regulation. METHODS: In a randomized crossover design, 12 subjects walked for 90 min on a treadmill in hot-dry (HD; 42.2 °C, 15% relative humidity (RH)) and warm-wet (WW; 30 °C, 80% RH) environments of equal WBGT (27.8 °C). Whole body sweat rate (WBSR) was determined by measuring body mass change. Ventilation (VE), respiratory rate (f), tidal volume (TV), respiratory exchange ratio (RER), and gas volumes (O2, CO2) were collected as 5-min averages, and core temperature (Tc, ingestible pill), heart rate (HR), and four-site mean skin temperature (Tsk) were recorded every 10 min. WBSR, S, evaporative heat loss (EHL), and dry heat gain (DHG) were assessed with paired t-tests and all other dependent variables with two-way analysis of variance (condition x time: 10, 50, 90 min). RESULTS: Tc (HD: 38.5 ± 0.5 °C; WW: 38.4 ± 0.4 °C, p = 0.38) and S (HD: 159 ± 235 W; WW: 359 ± 112 W, p = 0.06) increased during exercise (p < 0.01) and were not different between groups at min 90. Tsk (HD: 36.2 ± 0.9 °C; WW: 34.4 ± 0.7 °C, p < 0.01), HR (HD: 160 ± 19 bpm; WW: 154 ± 15 bpm, p = 0.03), and WBSR (HD: 15.1 ± 4.4 mL·min-1; WW: 10.0 ± 4.1 mL·min-1, p < 0.01) were greater in HD at min 90. Cumulative EHL (HD: 1203 ± 261 W; WW: 502 ± 126 W, p < 0.01) and DHG (HD: 221 ± 69 W; WW: -260 ± 72 W, p < 0.01) were higher in HD. VE (HD: 38.1 ± 9.8 L·min-1; WW: 37.6 ± 10.5 L·min-1, p = 0.64), its components f and TV (p = 0.12; p = 0.66, respectively), RER (HD: 0.86 ± 0.04; WW: 0.83 ± 0.04, p = 0.21) and the ventilatory equivalents for CO2 (HD: 34.6 ± 5.5 VE·VCO2-1; WW: 34.7 ± 4.3 VE·VCO2-1, p = 0.95) and O2 (HD: 29.9 ± 5.3 VE·VO2-1; WW: 28.8 ± 3.3 VE·VO2-1, p = 0.29) were not different at min 90 between trials nor when VE, VE·VCO2-1, and VE·VO2-1 were adjusted for change in Tc (p = 0.59; p = 0.26; p = 0.49, respectively). CONCLUSIONS: Different hot conditions of equal WBGT elicit similar increases in Tc, S, and ventilation, but higher cardiovascular strain was observed in HD compared to WW during walking in the heat.

Telemonitored Human Circadian Temperature Dynamics During Daily Routine.

BackgroundCircadian rhythms in body temperature coordinate peripheral molecular clocks, hence they could potentially predict optimal treatment timing (chronotherapy) in individual patients. Circadian parameters in chest surface body temperature (Chesttemp) were recorded remotely and in real time through the use of wearable sensors.MethodsThe dynamics of circadian oscillations in Chesttemp and core body temperature (Coretemp) and their moderation by sex and age were analysed in 38 men and 50 women, aged 21–78 years. In two studies (ST1 and ST2), Chesttemp was measured every minute and teletransmitted using a BLE-connected sensor for 3.6–28.3 days. Additionally, in ST2, Coretemp was recorded per minute in 33 age- and sex-stratified subjects using electronic ingestible pills with radio-frequency transmissions. Circadian parameters were computed using spectral analysis and cosinor modelling. The temporal relations between Chesttemp and Coretemp cosinor parameters were summarised with principal component (PC) analysis. The effect of sex and age was analysed through multivariate regression.ResultsUsing spectral analysis, a dominant period of 24- or 12-h was identified in 93.2% of the Chesttemp and in 100% of the Coretemp time series. The circadian parameters varied largely between-subjects both for Chesttemp (ranges: mesors, 33.2–36.6°C; amplitudes, 0.2–2.5°C; acrophases, 14:05–7:40), and Coretemp (mesors, 36.6–37.5°C; amplitudes, 0.2–0.7°C; bathyphases, 23:50–6:50). Higher PC loadings mainly corresponded to (i) large Chesttemp amplitudes, and phase advance of both temperature rhythms for the first PC (PC1, 27.2% of variance var.), (ii) high mesors in both temperature rhythms for PC2 (22.4% var.), and (iii) large Coretemp amplitudes for PC3 (12.9% var.). Chesttemp and Coretemp mesors and PC2 loadings decreased in females, while remaining quite stable in males as a function of age. In contrast, Coretemp amplitude and PC3 loadings increased with age in females, but decreased in males. Finally, older subjects, both female and male, displayed a reduction in ultradian variabilities, and an increase in both Chesttemp circadian amplitude and PC1 loadings.InterpretationThe dynamics relations between Chesttemp and Coretemp rhythms were largely moderated by age and sex, with results suggesting that treatment timing could be most critical for therapeutic index in women and in order people.

Human Brown Adipose Tissue is Active at Thermoneutrality in a Circadian Rhythm and is Highly Regulated in Winter Swimmers

To investigate human brown adipose tissue (BAT) physiology, we recruited young healthy men that were either winter swimmers (WS) or controls. We used 2-deoxy-2-[18F]fluoro-D-glucose PET/MRI-scanning, infrared thermography, iButtons and ingestible thermometer pills to assess BAT glucose uptake, and BAT and core temperature. In a crossover design with interventions performed in randomized order, subjects performed individualized cooling and thermoneutral protocols. We monitored a subset for BAT circadian rhythm. In response to cooling, WS increased more in BAT temperature, BAT glucose uptake and energy expenditure compared to control subjects. At thermoneutrality, WS had higher BAT temperature and lower core temperature, despite BAT glucose uptake in controls only. All subjects demonstrated a nocturnal reduction in BAT temperature, while a peak was observed at 4:30-5:30 am in WS, coinciding with rising plasma cortisol levels. In conclusion, WS have highly regulated BAT, and BAT is active at thermoneutrality in a circadian rhythm in humans.

Heat strain in children during unstructured outdoor physical activity in a continental summer climate

ABSTRACT The purpose of this study was to assess the heat strain experienced by children during unstructured physical activity outdoors in a temperate continental summer climate. Eighteen children (7 girls, 12.1 ± 1.7 years) performed up to 4 h of outdoor free-play (duration: 218 ± 33 min; air temperature of 24.5 ± 3.9°C and relative humidity of 66.2 ± 9.2%). Urine specific gravity (USG) was measured pre- and post-free-play, while body core temperature (Tco, ingestible pill) and heart rate (HR) were measured continuously. Physiological strain index (PSI) was calculated from Tco and HR (scale: 0 (none) to 10 (very high)). Activity levels were categorized as rest, light, moderate, and vigorous based on the metabolic equivalent of task, estimated from video analysis. Most children were euhydrated pre (78%, USG ≤ 1.020), but not post-free-play (28%, USG ≤ 1.020). Mean and peak Tco, HR, and PSI responses were 37.8 ± 0.3°C and 38.4 ± 0.3°C, 133 ± 14 bpm and 180 ± 12 bpm, and 4.7 ± 1.1 (low) and 7.4 ± 1.0 (high), respectively. All children reached peak Tco≥38.0°C, with seven ≥38.5°C, and the highest at 38.9°C. The children spent 58 ± 15% of free-play engaged in moderate-to-vigorous intensity physical activity. During free-play, all of the children performed moderate-to-vigorous intensity physical activity, which was associated with pronounced elevations in heat strain.

Feasibility of Continuous Monitoring of Core Body Temperature Using Chest-worn Patch Sensor.

With rapid advancement in wearable biosensor technology, systems capable of real time, continuous and ambulatory monitoring of vital signs are increasingly emerging and their use can potentially help improve patient outcome. Monitoring continuous body temperature offers insights into its trend, allows early detection of fever and is critical in several diseases and clinical conditions including septicemia, infectious disease and others. There is a complex interaction between physiological and ambient parameters including heart rate, respiratory rate, muscle rigors and shivers, diaphoresis, local humidity, clothing, body, skin and ambient temperatures among others. This article presents feasibility analysis of a wireless biosensor patch device called as VitalPatch in capturing this physio-ambient-thermodynamic interaction to determine core body temperature, and details comparative performance assessments using oral thermometer and ingestible pill as reference devices. Based on a study on a cohort of 30 subjects with reference oral temperature, the proposed method showed a bias of 0.1 ± 0.37 °C, mean absolute error (MAE) of 0.29 ± 0.25 °C. Another cohort of 22 subjects with continuous core body temperature pill as reference showed a bias of 0.16 ± 0.38 °C and MAE of 0.42 ± 0.22 °C.Clinical Relevance- Non-invasive, continuous and real time body temperature monitoring can lead to earlier fever detection and provides remote patient monitoring that can result in improved patient and clinical outcome.

Development of a modified predicted heat strain model for hot work environments

Excessive exposure to heat can lead to injuries, illness, and death among mineworkers. The actual cost of heat-related injuries and illnesses is unknown because of underreporting and lack of symptom recognition. Multi-factorial, evidence-based, and field-ready guidelines for identifying–and predicting–physiological markers of heat strain are currently unavailable. The predicted heat strain (PHS) model, is the latest attempt by mining companies to aid in the evaluation and management of occupational heat exposures. The adopted algorithm relies on worksite environmental measurements and an estimate of individual metabolic rate for mine workers to provide an estimate of the workers’ core temperature during a work shift. There are several known limitations of the PHS model, including the assumption that the subject worker is hydrated and fit. A modified PHS model was presented based on eight physical parameters that are measured at different intervals during a work shift; these parameters are air temperature, relative humidity, air velocity, radiation, metabolic rate, acclimatization, clothing insulation and posture. To validate the results, the predictions from the modified PHS model were compared with direct physiological measurements obtained from ingestible pills and heat stress monitors under different environmental and working conditions.

Influence of stomach mucosa tissue on the efficacy of intragastric antibacterial PDT.

In the field of photodynamic therapy (PDT), optimization of the in vivo therapeutic efficacy needs a comprehensive study of the photo-killing action spectrum that depends on both the photosensitizer (PS) absorption and the tissue optical properties. This is especially true in the case of gastric infections by Helicobacter pylori: PS absorption has been largely investigated in vitro, while the contribution of tissue optical properties and illumination geometry has been poorly studied, despite being parameters that reflect the specific in vivo conditions. To investigate their influence, we focussed on the case of a point-like light source positioned in the antrum. This models a therapeutic device developed by our team which consists of a LED-based ingestible pill. By a simple 3D illumination model, our approach mediates light-tissue interaction over the illuminated stomach wall surface, then calculates its average transmittance T by means of a 1D model representative of the mean gastric mucosa structure. Finally, by merging T(λ) with the photosensitizers' absorption we obtained the in vivo action spectrum. This shows two peaks at about 500 and 630 nm, indicating a noticeable influence of the tissue with respect to in vitro studies, where the action spectrum reflects PS absorption only. Our approach defines one average action spectrum for this specific therapeutic context, which reflects the need to choose one emission spectrum for the light source used. The proposed methodology could be applied to any other illumination geometry of cave organs, provided appropriate model modifications for the light source and tissue characteristics are made.