Feasibility and Usability Aspects of Continuous Remote Monitoring of Health Status in Palliative Cancer Patients Using Wearables.

BACKGROUND: Mobile health is a promising strategy aiming to anticipate and prevent the deterioration of health status in palliative cancer patients. A prerequisite for successful implementation of this technology into clinical routine is a high level of usability and acceptance of devices. OBJECTIVES: We aimed to evaluate feasibility as well as patients' acceptance of remote monitoring using wearables in palliative cancer patients. METHODS: In this prospective single-center observational feasibility study, 30 cancer patients treated with palliative intent in an inpatient setting with an estimated life expectancy of >8 weeks and <12 months were provided with a smartphone including a pre-installed "Activity Monitoring" app and a sensor-equipped bracelet and monitored over a period of 12 weeks starting at discharge from hospital. We report detailed feasibility and usability aspects and comment on patients' acceptance of the wearables. RESULTS: Between February 2017 and May 2018 a total of 30 patients were included in the study. From these, 25 participants (83%) completed the whole study period. On average, the bracelet was worn on 53% and smartphone used on 85% of the study days. The completion rate of daily digital questionnaires for subjective ratings (pain and distress scale) was 73%, and 28 patients were able to handle the wearables and to operate the app without major problems. Use of the bracelet was low during the night hours, with a wearing time of 1.7% of all night hours (8 p.m. to 8 a.m.). CONCLUSIONS: Remote monitoring of health care status in palliative cancer patients with a limited life expectancy is feasible and patients are able to handle the smartphone and the sensor-equipped bracelet. Feedback towards use of this monitoring system was mostly positive.

Mobile Health Technologies for Continuous Monitoring of Cancer Patients in Palliative Care Aiming to Predict Health Status Deterioration: A Feasibility Study.

Background: Unplanned readmissions or emergency visits (EVs) after discharge from hospital are frequent in patients in palliative care. Strategies to anticipate and prevent rapid deterioration of health are needed. Objective: Assessing feasibility and predictive ability of remote monitoring using wearables. Design: Prospective observational feasibility study in a single center. Setting/Subjects: Thirty cancer patients with an estimated life expectancy of >8 weeks to <12 months, aged >18 years and being discharged from inpatient to outpatient care were included. Measurements: Patients were provided with a smartphone, including the preinstalled "Activity Monitoring" application and a sensor-equipped bracelet. Follow-up was 12 weeks. Both devices recorded several features (e.g., vital signs). Visual analog scale (VAS) for pain and distress was reported once daily and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) once weekly. Statistical methods were applied to explore relationship between sensor data, self-reports, and EVs or readmissions or death. Results: Between February 2017 and May 2018, 30 patients were included. Twenty-five of 30 participants (83%) completed 12 weeks of follow-up. On average, bracelet was worn on 53% and smartphone on 85% of study days. Completion rate of daily digital questionnaires for subjective ratings was 73%. Eight unplanned hospital readmissions occurred. Ratings of pain, distress, and QLQ-C30 scores were not associated with readmission, whereas resting heart rate, resting heart rate variability, as well as speed of steps differed significantly in patients with and without readmission. Conclusions: Monitoring of palliative cancer patients using wearables is feasible. First results indicate that mobile health features might be promising biomarkers to predict unplanned readmissions.

On the Bending and Stretching of Liquid Metal Receive Coils for Magnetic Resonance Imaging.

The eGaIn coil on neoprene demonstrated in this paper presents a stretchable radio frequency receive coil for magnetic resonance imaging (MRI). The coil with dimensions [Formula: see text] is tuned to resonate at 128 MHz for 3 T MRI. We investigate the effect of stretching (up to 40% strain) and bending (50 mm radius of curvature) of the coil on the coil's resistance and resonance frequency. Measurements and simulations show a decrease in resonance frequency of 2.5 MHz per 10% strain. The higher resistivity of liquid metal compared to copper reduces the SNR of MRI scans by 34%; therefore, a tradeoff between flexibility and performance remains. Nevertheless, we have successfully performed MRI scans with the liquid metal coil.

Automatic Resonance Frequency Retuning of Stretchable Liquid Metal Receive Coil for Magnetic Resonance Imaging.

Stretchable magnetic resonance (MR) receive coils show shifts in their resonance frequency when stretched. An in-field receiver measures the frequency response of a stretchable coil. The receiver and coil are designed to operate at 128 MHz for a 3T MR scanner. Based on the measured frequency response, we are able to detect the changes of the resonance frequency of the coil. We show a proportional-integral-derivative controller that tracks the changes in resonance frequency and retunes the stretchable coil. The settling time of the control loop is less than 3.8ms. The retuning system reduces the loss in signal-to-noise ratio of phantom images from 1.6 dB to 0.3 dB, when the coil is stretched by 40% and the coil is retuned to 128 MHz.

Ge2Sb2Te5 p-Type Thin-Film Transistors on Flexible Plastic Foil.

In this work, we show the performance improvement of p-type thin-film transistors (TFTs) with Ge 2 Sb 2 Te 5 (GST) semiconductor layers on flexible polyimide substrates, achieved by downscaling of the GST thickness. Prior works on GST TFTs have typically shown poor current modulation capabilities with ON/OFF ratios ≤20 and non-saturating output characteristics. By reducing the GST thickness to 5 nm, we achieve ON/OFF ratios up to ≈300 and a channel pinch-off leading to drain current saturation. We compare the GST TFTs in their amorphous (as deposited) state and in their crystalline (annealed at 200 ∘ C) state. The highest effective field-effect mobility of 6.7 cm 2 /Vs is achieved for 10-nm-thick crystalline GST TFTs, which have an ON/OFF ratio of ≈16. The highest effective field-effect mobility in amorphous GST TFTs is 0.04 cm 2 /Vs, which is obtained in devices with a GST thickness of 5 nm. The devices remain fully operational upon bending to a radius of 6 mm. Furthermore, we find that the TFTs with amorphous channels are more sensitive to bias stress than the ones with crystallized channels. These results show that GST semiconductors are compatible with flexible electronics technology, where high-performance p-type TFTs are strongly needed for the realization of hybrid complementary metal-oxide-semiconductor (CMOS) technology in conjunction with popular n-type oxide semiconductor materials.

Evaluation of Piano Key Vibrations Among Different Acoustic Pianos and Relevance to Vibration Sensation.

Recent studies suggest that vibration of piano keys affect the perceived quality of the instrument, as well as the dynamic control and timing in piano playing. However, the time signals of piano key vibrations and its physical properties have not been analyzed and compared to the threshold of vibration sensation in a real-life playing situation yet. This study investigates piano key vibrations and explores the diversity of vibrations among different pianos with a laser Doppler vibrometer. A pianist was performing single keystrokes, note sequences, and a music piece excerpt on four concert grand pianos, five grand pianos, and two upright pianos. The measurements showed peak displacement levels up to 80 m and the frequency spectrum of the vibrations is dominated by frequencies lower than 500 Hz. Finally, a frequency weighting filter is introduced to show that vibration displacement time signals exceed the threshold of human vibration sensation for all evaluated instruments, when a note sequence is played in the bass to mid range with a single hand at forte level. The conducted experiments demonstrate that the vibration characteristics vary distinctively among the investigated pianos.

Metal-Halide Perovskites for Gate Dielectrics in Field-Effect Transistors and Photodetectors Enabled by PMMA Lift-Off Process.

Metal-halide perovskites have emerged as promising materials for optoelectronics applications, such as photovoltaics, light-emitting diodes, and photodetectors due to their excellent photoconversion efficiencies. However, their instability in aqueous solutions and most organic solvents has complicated their micropatterning procedures, which are needed for dense device integration, for example, in displays or cameras. In this work, a lift-off process based on poly(methyl methacrylate) and deep ultraviolet lithography on flexible plastic foils is presented. This technique comprises simultaneous patterning of the metal-halide perovskite with a top electrode, which results in microscale vertical device architectures with high spatial resolution and alignment properties. Hence, thin-film transistors (TFTs) with methyl-ammonium lead iodide (MAPbI3 ) gate dielectrics are demonstrated for the first time. The giant dielectric constant of MAPbI3 (>1000) leads to excellent low-voltage TFT switching capabilities with subthreshold swings ≈80 mV decade-1 over ≈5 orders of drain current magnitude. Furthermore, vertically stacked low-power Au-MAPbI3 -Au photodetectors with close-to-ideal linear response (R2 = 0.9997) are created. The mechanical stability down to a tensile radius of 6 mm is demonstrated for the TFTs and photodetectors, simultaneously realized on the same flexible plastic substrate. These results open the way for flexible low-power integrated (opto-)electronic systems based on metal-halide perovskites.

Photo-Induced Room-Temperature Gas Sensing with a-IGZO Based Thin-Film Transistors Fabricated on Flexible Plastic Foil.

We present a gas sensitive thin-film transistor (TFT) based on an amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) semiconductor as the sensing layer, which is fabricated on a free-standing flexible polyimide foil. The photo-induced sensor response to NO2 gas at room temperature and the cross-sensitivity to humidity are investigated. We combine the advantages of a transistor based sensor with flexible electronics technology to demonstrate the first flexible a-IGZO based gas sensitive TFT. Since flexible plastic substrates prohibit the use of high operating temperatures, the charge generation is promoted with the help of UV-light absorption, which ultimately triggers the reversible chemical reaction with the trace gas. Furthermore, the device fabrication process flow can be directly implemented in standard TFT technology, allowing for the parallel integration of the sensor and analog or logical circuits.

Adsorbed Eutectic GaIn Structures on a Neoprene Foam for Stretchable MRI Coils.

Stretchable conductors based on eutectic gallium-indium (eGaIn) alloy are patterned on a polychloroprene substrate (neoprene foam) using stencil printing. By tuning the amount of eGaIn on the neoprene substrate, different strain-sensitivity of electrical resistance is achieved. Conductors with a layer of eGaIn, which adsorbs to the walls of 60-100 µm wide neoprene cells, change their electrical resistance for 5% at 100% strain. When the amount of eGaIn is increased, the cells are filled with eGaIn and the strain-sensitivity of the electrical resistance rises to 300% at 100% strain. The developed conductors are patterned as stretchable on-body coils for receiving magnetic signals in a clinical magnetic resonance imaging setup. First images with a stretchable coil are acquired on an orange and compared to the images that are recorded using a rigid copper coil of the same size.

On-skin liquid metal inertial sensor.

A wireless on-skin inertial sensor based on free-moving liquid metal is introduced. The inertial sensor comprises a eutectic gallium-indium (eGaIn) droplet that modulates the capacitance between two electrodes. The capacitive output of the sensor is connected to a planar coil to form an LC resonator whose resonant frequency can be read out wirelessly. Liquid metal electrodes and the coil are fabricated on a 20 µm thick silicone membrane, which can stretch up to 600%, using spray-deposition of eGaIn. The moving droplet is encapsulated on the opposite side of the membrane using spray-deposition of Dragon Skin 10 silicone. The output characteristics, electrical simulations of the capacitance, and dynamic characteristics of the sensor are shown. The sensor is used for measuring tilt angles and recording arm gestures.

mHealth Technologies for Palliative Care Patients at the Interface of In-Patient to Outpatient Care: Protocol of Feasibility Study Aiming to Early Predict Deterioration of Patient's Health Status.

BACKGROUND: Palliative care patients are a particularly vulnerable population and one of the critical phases in patients' trajectories is discharge from specialized in-patient palliative care into outpatient care, where availability of a palliative care infrastructure is highly variable. A relevant number of potentially avoidable readmissions and emergency visits of palliative patients is observed due to rapid exacerbation of symptoms indicating the need for a closer patient monitoring. In the last years, different mHealth technology applications have been evaluated in many different patient groups. OBJECTIVE: The aim of our study is to test feasibility of a remote physical and social tracking system in palliative care patients. METHODS: A feasibility study with explorative, descriptive study design, comprised of 3 work packages. From the wards of the Clinic of Radiation-Oncology at the University Hospital Zurich, including the specialized palliative care ward, 30 patients will be recruited and will receive a mobile phone and a tracking bracelet before discharge. The aim of work package A is to evaluate if severely ill patients accept to be equipped with a tracking bracelet and a mobile phone (by semiquantitative questionnaires and guideline interviews). Work package B evaluates the technical feasibility and quality of the acquired electronic health data. Work package C will demonstrate whether physical activity parameters, such as step count, sleep duration, social activity patterns like making calls, and vital signs (eg, heart rate) do correlate with subjective health data and can serve as indicator to early detect and predict changes in patients' health status. Activity parameters will be extracted from the mobile phone's and wristband's sensor data using signal processing methods. Subjective health data is captured via electronic version of visual analog scale and Distress Thermometer as well as the European Organization for Research and Treatment of Cancer - Quality of Life Questionnaire C30 in paper version. RESULTS: Enrollment began in February 2017. First study results will be reported in the middle of 2018. CONCLUSIONS: Our project will deliver relevant data on patients' acceptance of activity and social tracking and test the correlation between subjective symptom assessment and objective activity in the vulnerable population of palliative care patients. The proposed study is meant to be preparatory work for an intervention study to test the effect of wireless monitoring of palliative care patients on symptom control and quality of life.

Buckled Thin-Film Transistors and Circuits on Soft Elastomers for Stretchable Electronics.

Although recent progress in the field of flexible electronics has allowed the realization of biocompatible and conformable electronics, systematic approaches which combine high bendability (<3 mm bending radius), high stretchability (>3-4%), and low complexity in the fabrication process are still missing. Here, we show a technique to induce randomly oriented and customized wrinkles on the surface of a biocompatible elastomeric substrate, where Thin-Film Transistors (TFTs) and circuits (inverter and logic NAND gates) based on amorphous-IGZO are fabricated. By tuning the wavelength and the amplitude of the wrinkles, the devices are fully operational while bent to 13 µm bending radii as well as while stretched up to 5%, keeping unchanged electrical properties. Moreover, a flexible rectifier is also realized, showing no degradation in the performances while flat or wrapped on an artificial human wrist. As proof of concept, transparent TFTs are also fabricated, presenting comparable electrical performances to the nontransparent ones. The extension of the buckling approach from our TFTs to circuits demonstrates the scalability of the process, prospecting applications in wireless stretchable electronics to be worn or implanted.

eHealth and mHealth interventions in the treatment of fatigued cancer survivors: A systematic review and meta-analysis.

OBJECTIVES: To (1) evaluate existing eHealth/mHealth interventions developed to help manage cancer-related fatigue (CRF); and (2) summarize the best available evidence on their effectiveness. METHODS: A comprehensive literature search of PubMed, MEDLINE, EMBASE, and the Cochrane Library up to November 2016 was conducted. Study outcomes were extracted, tabulated, and summarized. Random effects meta-analyses were conducted for the primary outcome (fatigue), and the secondary outcomes quality of life and depression, yielding pooled effect sizes (r), and 95% confidence intervals (CI). RESULTS: For eHealth interventions, our search of published papers identified 9 completed studies and 6 protocols for funded projects underway. No studies were identified for mHealth interventions that met our inclusion criteria. A meta-analysis of the 9 completed eHealth studies revealed a statistically significant beneficial effect of eHealth interventions on CRF (r = .27, 95% CI [.1109 - .4218], P < 0.01). Therapist-guided eHealth interventions were more efficacious then self-guided interventions (r = .58, 95% CI: [.3136 - .5985, P < 0.001). Small to moderate therapeutic effects were also observed for HRQoL (r = .17, 95% CI [.0384 - .3085], P < 0.05) and depression (r = .24, 95% CI [.1431 - .3334], P < 0.001). CONCLUSIONS: eHealth interventions appear to be effective for managing fatigue in cancer survivors with CRF. Continuous development of eHealth interventions for the treatment of CRF in cancer survivors and their testing in long-term, large-scale efficacy outcome studies is encouraged. The degree to which mHealth interventions can change CRF in cancer survivors need to be assessed systematically and empirically.

A Fully Integrated Dual-Channel On-Coil CMOS Receiver for Array Coils in 1.5-10.5 T MRI.

Magnetic resonance imaging (MRI) is among the most important medical imaging modalities. Coil arrays and receivers with high channel counts (16 and more) have to be deployed to obtain the image quality and acquisition speed required by modern clinical protocols. In this paper, we report the theoretical analysis, the system-level design, and the circuit implementation of the first receiver IC (RXIC) for clinical MRI fully integrated in a modern CMOS technology. The dual-channel RXIC sits directly on the sensor coil, thus eliminating any RF cable otherwise required to transport the information out of the magnetic field. The first stage LNA was implemented using a noise-canceling architecture providing a highly reflective input used to decouple the individual channels of the array. Digitization is performed directly on-chip at base-band by means of a delta-sigma modulator, allowing the subsequent optical transmission of data. The presented receiver, implemented in a CMOS technology, is compatible with MRI scanners up to . It reaches sub- noise figure for MRI units and features a dynamic range up to at a power consumption below per channel, with an area occupation of . Mounted on a small-sized printed circuit board (PCB), the receiver IC has been employed in a commercial MRI scanner to acquire in-vivo images matching the quality of traditional systems, demonstrating the first step toward multichannel wearable MRI array coils.

Supporting One-Time Point Annotations for Gesture Recognition.

This paper investigates a new annotation technique that reduces significantly the amount of time to annotate training data for gesture recognition. Conventionally, the annotations comprise the start and end times, and the corresponding labels of gestures in sensor recordings. In this work, we propose a one-time point annotation in which labelers do not have to select the start and end time carefully, but just mark a one-time point within the time a gesture is happening. The technique gives more freedom and reduces significantly the burden for labelers. To make the one-time point annotations applicable, we propose a novel BoundarySearch algorithm to find automatically the correct temporal boundaries of gestures by discovering data patterns around their given one-time point annotations. The corrected annotations are then used to train gesture models. We evaluate the method on three applications from wearable gesture recognition with various gesture classes (10-17 classes) recorded with different sensor modalities. The results show that training on the corrected annotations can achieve performances close to a fully supervised training on clean annotations (lower by just up to 5 percent F1-score on average). Furthermore, the BoundarySearch algorithm is also evaluated on the ChaLearn 2014 multi-modal gesture recognition challenge recorded with Kinect sensors from computer vision and achieves similar results.

Detecting Disordered Breathing and Limb Movement Using In-Bed Force Sensors.

We present and evaluate measurement fusion and decision fusion for recognizing apnea and periodic limb movement in sleep episodes. We used an in-bed sensor system composed of an array of strain gauges to detect pressure changes corresponding to respiration and body movement. The sensor system was placed under the bed mattress during sleep and continuously recorded pressure changes. We evaluated both fusion frameworks in a study with nine adult participants that had mixed occurrences of normal sleep, apnea, and periodic limb movement. Both frameworks yielded similar recognition accuracies of 72.1 ± âˆ¼  12% compared to 63.7 ± 17.4% for a rule-based detection reported in the literature. We concluded that the pattern recognition methods can outperform previous rule-based detection methods for classifying disordered breathing and period limb movements simultaneously.

A wearable bluetooth LE sensor for patient monitoring during MRI scans.

This paper presents a working prototype of a wearable patient monitoring device capable of recording the heart rate, blood oxygen saturation, surface temperature and humidity during an magnetic resonance imaging (MRI) experiment. The measured values are transmitted via Bluetooth low energy (LE) and displayed in real time on a smartphone on the outside of the MRI room. During 7 MRI image acquisitions of at least 1 min and a total duration of 25 min no Bluetooth data packets were lost. The raw measurements of the light intensity for the photoplethysmogram based heart rate measurement shows an increased noise floor by 50LSB (least significant bit) during the MRI operation, whereas the temperature and humidity readings are unaffected. The device itself creates a magnetic resonance (MR) signal loss with a radius of 14 mm around the device surface and shows no significant increase in image noise of an acquired MRI image due to its radio frequency activity. This enables continuous and unobtrusive patient monitoring during MRI scans.

Biomimetic Microelectronics for Regenerative Neuronal Cuff Implants.

Smart biomimetics, a unique class of devices combining the mechanical adaptivity of soft actuators with the imperceptibility of microelectronics, is introduced. Due to their inherent ability to self-assemble, biomimetic microelectronics can firmly yet gently attach to an inorganic or biological tissue enabling enclosure of, for example, nervous fibers, or guide the growth of neuronal cells during regeneration.

Prediction of Freezing of Gait in Parkinson's From Physiological Wearables: An Exploratory Study.

Freezing of gait (FoG) is a common gait impairment among patients with advanced Parkinson's disease. FoG is associated with falls and negatively impacts the patient's quality of life. Wearable systems that detect FoG in real time have been developed to help patients resume walking by means of rhythmic cueing. Current methods focus on detection, which require FoG events to happen first, while their prediction opens the road to preemptive cueing, which might help subjects to avoid freeze altogether. We analyzed electrocardiography (ECG) and skin-conductance (SC) data from 11 subjects who experience FoG in daily life, and found statistically significant changes in ECG and SC data just before the FoG episodes, compared to normal walking. Based on these findings, we developed an anomaly-based algorithm for predicting gait freeze from relevant SC features. We were able to predict 71.3% from 184 FoG with an average of 4.2 s before a freeze episode happened. Our findings enable the possibility of wearable systems, which predict with few seconds before an upcoming FoG from SC, and start external cues to help the user avoid the gait freeze.

Smartphone-based recognition of states and state changes in bipolar disorder patients.

Today's health care is difficult to imagine without the possibility to objectively measure various physiological parameters related to patients' symptoms (from temperature through blood pressure to complex tomographic procedures). Psychiatric care remains a notable exception that heavily relies on patient interviews and self-assessment. This is due to the fact that mental illnesses manifest themselves mainly in the way patients behave throughout their daily life and, until recently there were no "behavior measurement devices." This is now changing with the progress in wearable activity recognition and sensor enabled smartphones. In this paper, we introduce a system, which, based on smartphone-sensing is able to recognize depressive and manic states and detect state changes of patients suffering from bipolar disorder. Drawing upon a real-life dataset of ten patients, recorded over a time period of 12 weeks (in total over 800 days of data tracing 17 state changes) by four different sensing modalities, we could extract features corresponding to all disease-relevant aspects in behavior. Using these features, we gain recognition accuracies of 76% by fusing all sensor modalities and state change detection precision and recall of over 97%. This paper furthermore outlines the applicability of this system in the physician-patient relations in order to facilitate the life and treatment of bipolar patients.