Personal Monitoring Research Articles

Robust and flexible smart silk/PEDOT conductive fibers as wearable sensor for personal health management and information transmission

Flexible highly conductive fibers have attracted much attention due to their great potential in the field of wearable electronic devices. In this work, silk/PEDOT conductive fibers with a resistivity of 1.73 Ω·cm were obtained by oxidizing Ce3+ with H2O2 under alkaline conditions to produce CeO2 and further promote the in-situ polymerization of 3,4-ethylenedioxythiophene (EDOT) on the surface of silk fibers. The morphology and chemical composition of the silk/PEDOT conductive fibers were characterized and the results confirmed that a large amount of polythiophene was synthesized and deposited on the surface of silk fibers. The conductivity and electrochemical property stability of the silk/PEDOT conductive fibers were evaluated by soaping and organic solvent immersion, and the conductive silk fibers exhibited excellent environmental stability and durability. The silk/PEDOT conductive fibers show good pressure sensing and strain sensing performance, which exhibits high sensitivity, fast response and cyclability, and have excellent applications in personal health monitoring, human-machine information transmission, etc.

Thermoplastic Elastomers for Wireless, Skin‐Interfaced Electronic, and Microfluidic Devices

AbstractWireless, skin‐interfaced electronic and microfluidic devices have the potential to replace wired, bulky, and cumbersome technologies for personal and clinical health monitoring, allowing care to extend from hospital settings to the home. For use on skin, these devices commonly employ silicone‐based thermoset elastomers (TSEs) as layers that encapsulate the electronics or serve as molded microchannels for biofluid (e.g., sweat) capture, storage, and analysis. Barriers to commercial adoption of such devices include difficulties in use of these elastomers in conventional practices for mass manufacturing. Their relatively high cost and inability to allow for recycling represent additional disadvantages. By contrast, thermoplastic elastomers (TPEs) are fully compatible with industrial‐scale manufacturing processes, low in cost, and recyclable. Like TSEs, TPEs are soft, stretchable, flexible, and optically transparent, while possessing other properties well‐suited for applications in wireless, skin‐interfaced devices. Herein, the characteristics, processing, and application techniques for three commercially available TPEs, including two thermoplastic polyurethanes as encapsulation layers for a wireless skin hydration sensor and one thermoplastic styrenic block copolymer for a microfluidic sweat analysis platform, are reported. The results demonstrate that TPEs can be effectively integrated into these classes of devices, as a compelling alternative to TSEs, as a mass‐manufacturable, sustainable materials option.

Understanding the time-activity pattern to improve the measurement of personal exposure: An exploratory and experimental research

Although ambient fine particulate matter (PM2.5) concentrations and their components are commonly used as proxies for personal exposure monitoring, developing an accurate and cost-effective method to use these proxies for personal exposure measurement continues to pose a significant challenge. Herein, we propose a scenario-based exposure model to precisely estimate personal exposure level of heavy metal(loid)s (HMs) using scenario HMs concentrations and time-activity patterns. Personal exposure levels and ambient pollution levels for PM2.5 and HMs differed significantly with corresponding personal/ambient ratios of approximately 2, and exposure scenarios could narrow the assessment error gap by 26.1–45.4%. Using a scenario-based exposure model, we assessed the associated health risks of a large sample population and identified that the carcinogenic risk of As exceeded 1 × 10−6, while we observed non-carcinogenic risks from As, Cd, Ni, and Mn in personal exposure to PM2.5. We conclude that the scenario-based exposure model is a preferential alternative for monitoring personal exposure compared to ambient concentrations. This method ensures the feasibility of personal exposure monitoring and health risk assessments in large-scale studies.

Caffeic acid induced in-situ growth of AgNWs on cotton fabric for temperature and pressure sensing and electrical interference shielding

In recent years, smart wearable devices with thermal management, sensing response, and electromagnetic interference (EMI) shielding have gained great attention in multiple fields. In this work, high aspect ratios AgNWs with a diameter of 40 ∼ 60 nm and a length of 40 ∼ 60 μm generated in situ on the surface of cotton fabrics at room temperature using caffeic acid as reducing agent and anchoring agent, and polyvinypyrrolidone (PVP) as template agent. The preparation method is green, low cost and easy to scale up. The resulting flexible silver nanowire/cotton fabric (AgNW/cotton fabric) with a sheet resistance of 0.23 Ω/sq possesses good physical properties, excellent and durable stability of electrical conductivity. The prepared flexible AgNW/cotton fabric show good temperature and pressure sensing performance. Temperature sensing performance of AgNW/cotton fabric allows it to be used as a temperature alarm in agricultural greenhouses and textile fire. Pressure sensing of AgNW/cotton fabric exhibits high sensitivity (∼-53 % kPa−1), fast response (100 ms), low detection limit (73.1 mg) and recyclability, which reveals its potential practical value for personal health monitoring, human–computer interaction and entertainment. AgNW/cotton fabric can quickly reach 54.8 °C and 86.2 °C through electrical-thermal and photo-thermal conversions, respectively, which is hopefully used as a wearable heater for self-heating garments and smart heat therapy. Additionally, AgNW/cotton fabric exhibits an EMI shielding efficiency of 38.2 dB in X-band. AgNW/cotton fabrics have great potential in manufacturing flexible, breathable and multi-functional flexible wearable textile devices.

Facile and Scalable Fabrication of Hydrophilic/Hydrophobic Janus Fabric for Personal Sweat Monitoring and Perspiration Management

AbstractQuantifiable monitoring and management of sweat volume have attracted considerable attention because of their role in assessing physiological health and preventing dehydration. However, defective sweat monitoring and poor moisture management limit the performance of most smart textiles under moderate/profuse perspiration scenarios. In this study, a large‐scale fabrication technology is used, including braiding and weaving, to prepare a hydrophilic/hydrophobic Janus fabric (HHJF) with good directional water delivery and sweat‐volume monitoring capabilities. The HHJF consists of polytetrafluoroethylene (PTFE) braided yarns (lower layer) and Tencel braided yarns (upper layer), which comprise a conductive yarn as the core and PTFE/Tencel yarns as the sheath with enhanced water absorption capacity. The unique functional structure design achieves the enhanced unidirectional water transport and high sweat‐sensing response for the HHJF under perspiration conditions. The optimized HHJF facilitates spontaneous droplet penetration from the hydrophobic layer to the hydrophilic layer, while enabling the real‐time detection of sweat volume of up to 2000 mL m−2 with excellent durability for over 1000 cycle tests. Thus, the exceptional perspiration management and monitoring capabilities of HHJF are expected to promote the development of practical smart textiles that enable real‐time monitoring of perspiration dynamics.

Short-term multifactorial intervention (STEMI): An approach using structured blood glucose monitoring (BGM) and conventional therapies in persons with diabetes

ABSTRACT Background: Achieving glucose and glycosylated hemoglobin (HbA1c) targets have been shown to reduce long-term microvascular complications of diabetes; however, suboptimal glucose control is common. We tested whether glucose control could be improved within 8 weeks by employing structured blood glucose monitoring (BGM) qid in addition to seven times per day prior to visits for diabetes education and medication management that occurred every 2–4 weeks. Methods: This single-center, prospective study was conducted on 78 adults with either type 1 diabetes (T1D) or type 2 diabetes (T2D), HbA1c >8%, and serum creatinine (sCr) <2.0 mg/dl. HbA1c was checked at baseline, Week 2, Week 4, and at Week 8. Patients were evaluated by a physician and a certified diabetes educator (CDE) at baseline, Week 2, and Week 4 for treatment adjustments and lifestyle advice based on a review of BGM done qid plus 7-point profiles conducted before Weeks 2, 4, and 8. Study outcomes were change in HbA1c from baseline to Week 8 and change in mean glucose on the 7-point profile from Week 2 to Week 8. These were compared using one-way repeated measures ANOVA. Results: Of the 78 patients, 64.1% had T2D, 50% were women, and 72% were Caucasian. Mean age (±SD) was 51.3.5 ± 11.1 years, and median diabetes duration was 9 (5–17) years. The percentage of patients using insulin increased from 58.9% at baseline to 67.9% at Week 8. The mean (±SD) HbA1c was 9.53% (±1.71) at baseline, declined -1.38% from baseline to week 8 (CI -1.62 to -0.14, P < 0.001). The mean (±SD) glucose on the 7-point profile was 187 (±52) mg/dl at Week 2, and 157 (±5) mg/dl at Week 8. (P < 0.01). Conclusions: An intensive glucose optimization program using structured BGM qid plus 7-point profiles, diabetes education, and conventional anti-diabetic therapies was successful in reducing HbA1c by 1.38% over 8 weeks in patients with poor glucose control.

Impact of radon on personal contamination monitors at the exit of the restricted controlled areas in EDF nuclear power plant

Background: Between 2008 and 2017, EDF has progressively replaced its old Personal Contamination Monitors (PCM) with a new generation to strengthen the control of the workers at the exit of the restricted controlled areas. One of the novelties of the new PCM generation is the introduction of gamma channels which, coupled to the beta channel, allows a more reliable and more precise measurement. The new PCM also includes a better monitoring of the C2 portals alarms triggering system, a greater detection surface to minimize the dead zone and carries out morphological compensation to take into account the attenuation of the gamma background by the body. This new PCM is very efficient and capable of detecting low contamination activities. The sensitivity of this monitoring system is such that the solid progeny of 222Rn deposited on clothes (such as the 214Pb and the 214Po) could in some cases be detected and triggered the C2 portals alarm. Objective: In order to quantify the impact of radon (222Rn) and its progeny on the C2 portals triggers, a specific study has been conducted. Beyond the physical aspect, several purposes are targeted: (1) to provide quantitative explanations about the C2 alarms attributed to radon and determine which channels are more affected by the 222Rn progeny; (2) to determine the existence of a relation between C2 alarms and high 222Rn volume activity; (3) to optimize practices at the exit of the Restricted Controlled Areas (RCA), for example, adapt waiting time before control in PCM. The study consisted in measuring the activity of radon progeny deposited on several types of suits used in EDF Nuclear Power Plants (NPPs). To assess the impact of the 222Rn, several factors have been studied such as the 222Rn exposure time, the 222Rn concentration and the nature of textile fibers constituting clothes. For this study, several facilities from the Laboratoire de Physique des deux infinis de Bordeaux (LP2i Bordeaux) have been used, including a 222Rn emanation standard source and various emanation chambers between 60 L and 750 L. A specific calibration method to characterize radon progenies deposited has been developed (see Sects. 2.4 and 3). The 222Rn concentration in the sample exposure environment is verified both using a commercial (see Sects. 2.4 and 3) and experimental high sensitivity radon detectors. The measurements of the 222Rn progeny on clothes are made immediately after exposure by gamma spectrometry control on a High Purity Germanium (HPGe) detector. This experiment has been carried out at the PRISNA measurement platform (Plateforme Régionale Interdisciplinaire de Spectrométrie Nucléaire en Aquitaine) located in LP2I Bordeaux. Conclusions: In this study, several phenomena have been highlighted for a better understanding of the C2 portal triggering. We validate that in presence of 222Rn volume concentration activity lower than 300 Bq/m3, an alarm in beta channels of C2 portals can be triggered because of the presence of the radon progeny on clothes. The triggering of the gamma channels could appear only if the volume concentration activity of radon is higher than 3000 Bq/m3. The results obtained in this study could led to optimize and harmonize the practices at the exit of Restricted Controlled Area (RCA) like adapt waiting time before control in PCM.

Preferences of young adults on the development of a new digital add-on alcohol intervention for depression treatment: A qualitative study

AimTo explore the preferences of young adults with regard to the development of a new digital add-on alcohol intervention to complement depression treatment. MethodsThis qualitative study included young adults (18–35 years) with experience of either problematic alcohol use or depression or both (n = 29). Two rounds of focus groups were conducted, with two focus groups in each round. All focus groups were recorded, transcribed and analysed deductively and inductively on the basis of qualitative content analysis of the intervention type, features and design. ResultsYoung adults preferred a mobile health application with a clear and simple objective and navigation which was also accessible on a computer. With regard to intervention features, participants indicated a preference for in-depth, gain-framed information on alcohol use and a main feature enabling them to record their alcohol use and mood, which would be rewarded. Other preferences included personal goal-setting and monitoring, an activity list, experience stories, peer contact, guidance from experts by experience or volunteers and receiving notifications from the application. In terms of design, participants preferred short, animated videos and animation figure illustrations to complement written text. Moreover, participants rated the design of the intervention as highly important, yet very personal. Generally, participants preferred a light pastel colour scheme. Once again, participants indicated a need for a clear dashboard using pictograms to reduce the amount of text and fast, easy-to-use navigation. ConclusionThe preferences indicated by young adults with regard to the intervention type, features and design may enhance the development of a new digital add-on alcohol intervention to complement depression treatment.

Applicability of multiple impulse-radar sensors for the recognition of a person’s action

The research reported in this paper is devoted to the impulse-radar technology when applied for non-intrusive monitoring of elderly persons. Specifically, this study is focused on a novel approach to the interpretation of data acquired by means of multiple impulse-radar sensors, leading to the determination of features to be used for the recognition of a monitored person’s actions. The measurement data are first transformed into the three-dimensional coordinates of the monitored person; next, those coordinates are used as a basis for determination of features characterising the movement of that person. The results of the experimentation, based on the real-world data, show that multiple impulse-radar sensors may be successfully used for highly accurate recognition of actions such as walking, sitting, and lying down, although this accuracy is significantly affected by the quality of the three-dimensional movement trajectories which in turn is affected by the configuration of the impulse-radar sensors within the monitored area.

Wearable and Flexible Nanoporous Surface-Enhanced Raman Scattering Substrates for Sweat Enrichment and Analysis

Surface-enhanced Raman spectroscopy (SERS), with high sensitivity to a broad range of molecules, can detect molecular “fingerprints” in a complex substance and thereby offers a promising solution for noninvasive medical diagnostics and personal healthcare monitoring. The eventual realization of such applications relies on SERS substrates with dense and uniform hot spots, good chemical stability, and high mechanical durability. With these criteria in mind, we developed a flexible nanoporous SERS substrate via the in situ synthesis of gold nanostars (AuNSs) on an ion-track-etched polycarbonate membrane. The nanoporous SERS substrate can realize analyte enrichment and exhibit excellent Raman performance by taking the advantage of hot spots on AuNSs. The SERS substrate yields highly repeatable and uniform signals for analytes (e.g., methylene blue) over a wide concentration range from 10–4 to 10–13 M. The flexible SERS substrate even can work well after 2000 times bending and exhibit excellent stability for long-term use. It can be prepared on a large scale with a low-cost and simple fabrication process and can be used repeatedly after cleaning to reduce the use-cost further. On-body experiments prove that the sweat SERS substrate allows effective identification of sweat contents, such as lactic acid and uric acid (UA), and the monitoring of diet-induced variation in sweat UA. The potential of the wearable nanoporous SERS substrates in sweat analysis thus has been demonstrated, opening possibilities for autonomous and noninvasive medical health monitoring.

Velocity-Based Strength Training: The Validity and Personal Monitoring of Barbell Velocity with the Apple Watch.

Velocity-based training (VBT) is a method to monitor resistance training based on measured kinematics. Often, measurement devices are too expensive for non-professional use. The purpose of this study was to determine the accuracy and precision of the Apple Watch 7 and the Enode Pro device for measuring mean, peak, and propulsive velocity during the free-weighted back squat (in comparison to Vicon as the criterion). Velocity parameters from Vicon optical motion capture and the Apple Watch were derived by processing the motion data in an automated Python workflow. For the mean velocity, the barbell-mounted Apple Watch (r = 0.971-0.979, SEE = 0.049), wrist-worn Apple Watch (r = 0.952-0.965, SEE = 0.064) and barbell-mounted Enode Pro (r = 0.959-0.971, SEE = 0.059) showed an equal level of validity. The barbell-mounted Apple Watch (Vpeak: r = 0.952-0.965, SEE = 0.092; Vprop: r = 0.973-0.981, SEE = 0.05) was found to be the most valid for assessing propulsive and peak lifting velocity. The present results on the validity of the Apple Watch are very promising, and may pave the way for the inclusion of VBT applications in mainstream consumer wearables.

Emissions and Exposures Associated with the Use of an Inconel Powder during Directed Energy Deposition Additive Manufacturing.

Additive manufacturing (AM) has been linked to potential exposure-related health risks, however, there is a paucity of sufficient research. This study aimed to supply information regarding emissions and exposure during directed energy deposition (DED) AM using inconel 718, with the main constituents being nickel, chromium, and cobalt. By using standardized occupational hygiene methods, the measurement strategy consisted of a combined approach, including powder characterization, particle emission monitoring, and personal exposure monitoring of AM operators. Powder characterization of virgin and used powder indicated no significant difference in particle size, shape, or elemental composition. Particle number emissions ranged between 102 and 105 p/cm3 for submicron particles (<1 µm in size). There was no significant difference in the particle emission rate between the three phases of AM or the two types of DED machines (p > 0.05). The particle emission rate for submicron particles peaked at 2.8 × 109 p/min. Metals of concern to human health were detected during the AM process but were considerably lower than the relevant exposure limits. This study confirms particle emissions, predominantly in the submicron range, above the background concentration during DED AM and, although insignificant in terms of potential health effects, AM operators are exposed to detectable concentrations of the metal constituents of inconel.

738-P: Lifestyle Intervention Program with Smartphone App Augmented by Intermittently Scanned Continuous Glucose Monitoring for People at High Risk of Diabetes—Randomized Controlled Trial

We examined the effects of a lifestyle intervention program with a smartphone app augmented by intermittently scanned continuous glucose monitoring (isCGM) of persons at high risk of developing diabetes in a 12-week randomized open-label trial (UMIN00004640). The program monitored blood glucose fluctuations and lifestyle habits and displayed them in an easy-to-understand interface as well as provided personalized lifestyle intervention messages. The primary endpoint was the change in time in range (TIR) of 70-140 mg/dL between intervention (App) and control (C) groups. Among 168 patients (mean age 48.1 y, mean BMI 26.6 kg/m2, and male 80.4%), 82 and 86 were assigned to the App group and C group, respectively. After 12 weeks, TIR of 70-140 mg/dL significantly improved in the App group compared to the C group (-2.6 min/day vs. +31.5 min/day, p=0.03). Changes in time above range (&amp;gt;140 mg/dL; -20.9 min/day vs. -22.6 min/day, p=0.86) did not differ, whereas time below range (&amp;lt;70 mg/dL; +23.5 min/day vs. -8.9 min/day, p=0.02) improved in App compared to C. BMI (-0.26 vs. -0.59, p=0.017) and carbohydrate intake (-4.4 kcal/day vs. -22.7 kcal/day, p=0.049) also improved in App compared to C. Intervention with a smartphone app and isCGM increased glycemic control with a decrease in carbohydrate intake and weight loss. Disclosure M.Kitazawa: None. H.Sone: Research Support; Novo Nordisk, Astellas Pharma Inc., Kyowa Kirin Co., Ltd., Taisho Pharmaceutical Holdings Co., Ltd., Ono Pharmaceutical Co., Ltd., Eisai Co., Ltd., Takeda Pharmaceutical Co., Ltd. H.Suzuki: None. C.Horikawa: None. Y.Takeda: None. I.Ikeda: None. M.Hatta: None. M.Iwanaga: None. T.Yamada: None. K.Fujihara: None.

970-P: Effectiveness of Continuous Glucose Monitoring Use for Diabetes Management in an Academic Endocrinology Practice

The achievement of individualized glycemic targets in patients with diabetes is often a significant challenge. Empowering patients with technological tools in the ambulatory setting can pave the way for improved glucose control. We retrospectively examined the records of 94 patients managed in an academic endocrinology practice who were referred for management of diabetes over a 12-month period. Forty-one patients (18 females and 23 males, average age 57.7 years), who had at least two hemoglobin A1c measurements and two 14-day periods of personal continuous glucose monitoring (CGM) data, were included in the analysis. Nine patients had type 1 and 32 patients had type 2 diabetes. Eight patients were not on any insulin therapy, 8 patients were on basal insulin, 18 were using multiple daily insulin injections, and 7 were managed with insulin pump therapy. A multidisciplinary management approach was utilized. The pharmacologic regimen, including both insulin and other medications, was adjusted every 2-4 weeks via in-person visits and remote data upload as necessary. The average A1c was 8.4% at initial visit and 7.1% at the most recent follow-up, a decrease of 1.3% (p=0.0002). Review of CGM data showed that the average time-in-range (70-180 mg/dl) increased from 63.6% at first CGM download to 74.1% at a mean follow-up of 301 days (p=0.0097), while the amount of time in the hyperglycemic range (time-above-range, &amp;gt;180 mg/dl) decreased from 33.5% to 22.1% (p=0.0079). Time-below-range (&amp;lt;70 mg/dl) remained statistically unchanged, signifying no worsening of hypoglycemia. In conclusion, in ambulatory patients with diabetes and suboptimal glucose control, frequent and tailored adjustments in insulin and noninsulin medications aided by CGM use with close follow-up can lead to significant improvement in glycemic control. The latter, if sustained, can translate to fewer complications and greater patient satisfaction in the long-term. Disclosure K.N.Grennan: None. A.A.Rizvi: None. A.Kathuria: None.

Identification of Core Outcome Domains and Design of a Survey Questionnaire to Evaluate Impacts of Digital Health Solutions That Matter to People With Diabetes.

Digital health solutions (DHS) are increasingly used to support people with diabetes (PwD) to help manage their diabetes and to gather and manage health and treatment data. There is a need for scientifically reliable and valid methods to measure the value and impact of DHS on outcomes that matter to PwD. Here, we describe the development of a survey questionnaire designed to assess the perceptions of PwD toward DHS and their prioritized outcomes for DHS evaluation. We applied a structured process for engagement of a total of nine PwD and representatives of diabetes advocacy organizations. Questionnaire development consisted of a scoping literature review, individual interviews, workshops, asynchronous virtual collaboration, and cognitive debriefing interviews. We identified three overarching categories of DHS, which were meaningful to PwD and crucial for the identification of relevant outcomes: (1) online/digital tools for information, education, support, motivation; (2) personal health monitoring to support self-management; (3) digital and telehealth solutions for engaging with health professionals. Overall outcome domains identified to be important were diabetes-related quality of life, distress, treatment burden, and confidence in self-management. Additional positive and negative outcomes specific to DHS were identified and corresponding questions were incorporated into the survey questionnaire. We identified the need for self-reporting of quality of life, diabetes distress, treatment burden, and confidence in self-management, as well as specific positive and negative impacts of DHS. We designed a survey questionnaire to further assess the perceptions and perspectives of people with type 1 and 2 diabetes on outcomes relevant for DHS evaluations.

Mussel-inspired cellulose nanofiber/poly(vinyl alcohol) hydrogels with robustness, self-adhesion and antimicrobial activity for strain sensors

Flexible strain sensors have attracted substantial attention given their application in human-computer interaction and personal health monitoring. Due to the inherent disadvantages of conventional hydrogels, the manufacture of hydrogel strain sensors with high tensile strength, excellent adhesion, self-healing and antimicrobial properties in vitro, and conductive stability is still a challenge. Herein, a conductive hydrogel consisting of polydopamine-coated cellulose nanofibers (CNF@PDA), carbon nanotubes (CNT), and polyvinyl alcohol (PVA) was developed. The CNTs in PVA/CNF@PDA/CNT hydrogels were uniformly dispersed in the presence of CNF@PDA by hydrogen bonding, resulting in a nearly threefold increase in conductivity (0.4 S/m) over hydrogels without PDA. The hydrogel exhibited satisfactory tensile properties (tensile stress up to 0.79 MPa), good fatigue resistance, self-recovery and excellent antimicrobial activity in vitro. It showed excellent adhesion, especially the adhesion strength of pigskin was increased to 27 kPa. In addition, the hydrogel was used as a strain sensor, exhibiting excellent strain sensitivity (strain coefficient = 2.29), fast response (150 ms), and great durability (over 1000 cycles). The fabricated strain sensors can detect both large and subtle human movements (e.g., wrist bending and vocalization) with stable and repeatable electrical signals, indicating potential applications in personal health monitoring.

Hybrid Device Fabrication Using Roll-to-Roll Printing for Personal Environmental Monitoring.

Roll-to-roll (R2R) printing methods are well known as additive, cost-effective, and ecologically friendly mass-production methods for processing functional materials and fabricating devices. However, implementing R2R printing to fabricate sophisticated devices is challenging because of the efficiency of material processing, the alignment, and the vulnerability of the polymeric substrate during printing. Therefore, this study proposes the fabrication process of a hybrid device to solve the problems. The device was created so that four layers, composed of polymer insulating layers and conductive circuit layers, are entirely screen-printed layer by layer onto a roll of polyethylene terephthalate (PET) film to produce the circuit. Registration control methods were presented to deal with the PET substrate during printing, and then solid-state components and sensors were assembled and soldered to the printed circuits of the completed devices. In this way, the quality of the devices could be ensured, and the devices could be massively used for specific purposes. Specifically, a hybrid device for personal environmental monitoring was fabricated in this study. The importance of environmental challenges to human welfare and sustainable development is growing. As a result, environmental monitoring is essential to protect public health and serve as a basis for policymaking. In addition to the fabrication of the monitoring devices, a whole monitoring system was also developed to collect and process the data. Here, the monitored data from the fabricated device were personally collected via a mobile phone and uploaded to a cloud server for additional processing. The information could then be utilized for local or global monitoring purposes, moving one step toward creating tools for big data analysis and forecasting. The successful deployment of this system could be a foundation for creating and developing systems for other prospective uses.

Assessment of children's personal and land use regression model-estimated exposure to NO2 in Springfield, Massachusetts

Ambient nitrogen dioxide (NO2) is derived from tailpipe vehicle emission and is linked with various of health outcomes. Personal exposure monitoring is crucial for accurate assessment of the associated disease risks. This study aimed to evaluate the utility of a wearable air pollutant sampler in determining the personal NO2 exposure of school children for comparison with a model-based personal exposure assessment. We employed cost-effective, wearable passive samplers to directly measure personal exposure of 25 children (aged 12–13 years) in Springfield, MA to NO2 over a five-day period in winter 2018. NO2 levels were additionally measured at 40 outdoor sites in the same region using stationary passive samplers. A land use regression (LUR) model was developed based on the ambient NO2 measures, with a good prediction performance (R2 = 0.72) using road lengths, distance to highway, and institutional land area as predictor variables. Time-weighted averages (TWA), which incorporated the time-activity patterns of participants and LUR-derived estimates in children's primary microenvironments (homes, the school and commute paths), were calculated as an indirect measure of personal NO2 exposure. Results indicated that the conventional residence-based exposure estimate approach, often used in epidemiological studies, differed from the direct personal exposure and could overestimate the personal exposure by up to 109 %. TWA improved personal NO2 exposure estimates by accounting for the time activity patterns of individuals, a difference of 5.4 % ± 34.2 % was found for exposures compared to wristband measurements. Nevertheless, the personal wristband measurements exhibited a large variability due to the potential contributions from indoor and in-vehicle NO2 sources. The findings suggest that exposure to NO2 can be highly personalized based on individual activities and contact with pollutants in specific microenvironments, reaffirming the importance of measuring personal exposure.

Template-Based Generator for Single-Choice Questions

Manual composition of tasks and exams is a challenging and time-consuming task. Especially when exams are taken remotely without the personal monitoring by examiners, most exams can easily lose their integrity with the use of previously done exercises or student communication. This research introduces an approach that incorporates the principles of the generative software development and aspects of the feature-oriented product line engineering process into the field of question creation and generation. The resulting generator can be used to generate single-choice-question-families by means of written question templates. The generated questions within a question-family differ based on the set features and parameters and can be imported into the target learning management system ILIAS. Without much effort, examiners and educators can use the generator to create variants of their questions and deliver them to their students.

Optimal sensor placement for personal inhalation exposure detection in static and dynamic office environments

Modern health and productivity concerns related to air pollutant exposure in buildings have sparked the need for occupant-centric monitoring and ventilation control. The existing personal exposure monitoring is often restricted to stationary air quality sensors and static occupancy. This study aims to identify optimal stationary sensor placement that best represents exposure to CO2, PM2.5, and PM10 under static and dynamic office occupancies. A total of 48 controlled chamber experiments were executed in four office layouts with variation of occupant numbers (2, 4, 6 or 8), activities (sitting/standing and static/dynamic), ventilation strategies (mixing/displacement) and air change rates (0.5–0.7 h−1, 2.4–2.6 h−1, and 3.8–4.2 h−1). The breathing zone concentration of a reference occupant was monitored with concurrent measurements at seven stationary locations: front edge of the desk, sides of two desks, two sidewalls, and two exhaust vents. The proximity of sensors to the reference occupant and ventilation rate/strategy were important determinants of personal exposure detection. Regression analyses showed that the wall- and desk-mounted CO2 sensors near the occupant (<1 m) best captured CO2 exposure under dynamic–standing activities (R2∼0.4). The wall immediately behind the seated occupant and the ceiling-mounted exhaust near the standing occupant (<1–1.5 m) were the best sensor placements for capturing exposure to particles (R2=0.8–0.9). Separating static from dynamic occupancy activities resulted in improved exposure prediction by 1.4-6.1× . This study is a step towards provision of practical guidelines on stationary air quality sensor placement indoors with the consideration of dynamic occupancy profiles.