Multimode Devices Research Articles

The State of the Field of Pediatric Multimodality Neuromonitoring.

The use of multimodal neuromonitoring in pediatrics is in its infancy relative to adult neurocritical care. Multimodal neuromonitoring encompasses the amalgamation of information from multiple individual neuromonitoring devices to gain a more comprehensive understanding of the condition of the brain. It allows for adaptation to the changing state of the brain throughout various stages of injury with potential to individualize and optimize therapies. Here we provide an overview of multimodal neuromonitoring in pediatric neurocritical care and its potential application in the future. Multimodal neuromonitoring devices are key to the process of multimodal neuromonitoring, allowing for visualization of data trends over time and ideally improving the ability of clinicians to identify patterns and find meaning in the immense volume of data now encountered in the care of critically ill patients at the bedside. Clinical use in pediatrics requires more study to determine best practices and impact on patient outcomes. Potential uses include guidance for targets of physiological parameters in the setting of acute brain injury, neuroprotection for patients at high risk for brain injury, and neuroprognostication. Implementing multimodal neuromonitoring in pediatric patients involves interprofessional collaboration with the development of a simultaneous comprehensive program to support the use of multimodal neuromonitoring while maintaining the fundamental principles of the delivery of neurocritical care at the bedside. The possible benefits of multimodal neuromonitoring are immense and have great potential to advance the field of pediatric neurocritical care and the health of critically ill children.

Challenges in the microwave heating of structured carbon adsorbents

Microwave heating is a promising method for achieving energy-efficient electrification of temperature swing adsorption processes. However, to successfully design the adsorbent bed and the regeneration step, it is crucial to analyse the limited penetration depth of microwaves. In this study, we present the first comprehensive investigation of microwave heating applied to large structured activated carbon adsorbents. The experiments were conducted inside a monomode microwave applicator, which consists of a rectangular waveguide operated at a frequency of 915 MHz. monolithic adsorbents of various shapes and sizes (cubic, rectangular cuboid, cylindrical) with dimensions up to 10 cm, were placed inside the cavity and subjected to microwave powers ranging from 10 to 200 W. To maximise microwave absorption by the sample, the geometry and impedance of the cavity were modified. Temperature measurements were taken at different positions within the monoliths to investigate heating homogeneity. The combined influence of reflections and the limited penetration depth results in very different temperature profiles as the size and shape of the monolith vary, even after optimising the cavity. In general, thinner monoliths heat better at the centre, whereas thicker monoliths experience better heating at the point closer to the radiation source. Additionally, these materials were characterized in terms of their dielectric and textural properties and composition, and it was determined that variations in these properties result in significant differences in the heating behavior. The choice of adsorbent bed size and heating time can be adjusted accordingly to maximise energy efficiency and heating homogeneity. Furthermore, the rotation of monoliths within the monomode electromagnetic field to achieve heating homogeneity is examined and a comparison with a multimode device is established.

MGrx - A Novel Multi-modal Thermal Device for Treating Moderate to Severe Meibomian Gland Dysfunction and Dry Eye

Background: MGD (meibomian gland dysfunction) is a chronic cause of dry eyes. Thermal expression of the meibomian glands, along with massage and debridement, is an effective treatment for MGD. Objective: We describe a multi-modal thermal device (MGrx) to manage meibomian gland dysfunction (MGD). We observed the efficacy and safety of the MGrx to manage MGD in one 15-minute in-office session. Methods: We enrolled 37 patients in a prospective, open-label trial of the novel MGrx. Patients were enrolled with a Standard Patient Evaluation for Eye Dryness (SPEED) score > 12 or a Tear Breakup Time (TBUT) of < 6 seconds in at least one eye. After screening for eligibility, one 15-minute MGrx treatment was provided to each patient. The patient assessment consisted of a SPEED score, TBUT, and a Meibomian gland score (MGS) obtained pre-treatment and at a follow-up visit 30 days after the treatment. Results: Dry eye symptoms improved in the patient population, as measured by SPEED score, MGS, and TBUT, by 40%, 341%, and 145%, respectively (p<0.05). No adverse reactions were noted among the patients. Conclusion: A single 15-minute MGrx treatment was effective at significantly improving dry eye symptoms secondary to MGD in adult patients, as measured by SPEED score. Additionally, a single MGrx treatment improved meibomian gland function and all measures of MGD in the adult patients treated. Given the relatively low risk and efficient delivery of the MGrx treatment, a single MGrx treatment should be considered as a first-line treatment for MGD.

Dual-modal piezotronic transistor for highly sensitive vertical force sensing and lateral strain sensing

Mechanical sensors are mainly divided into two types (vertical force sensing and lateral strain sensing). Up to now, one sensor with two working modes is still a challenge. Here, we demonstrate a structural design concept combing a piezoelectric nano/microwire with a flexible polymer with protrusions that enables a dual-modal piezotronic transistor (DPT) with two working modes for highly sensitive vertical force sensing and lateral strain sensing. For vertical force sensing, DPT exhibits a force sensitivity up to 221.5 N−1 and a minimum identifiable force down to 21 mN, corresponding to a pressure sensitivity of 1.759 eV/MPa. For lateral strain sensing, DPT can respond to a large compression strain (~5.8%) with an on/off ratio up to 386.57 and a gauge factor up to 8988.6. It is a universal design that can integrate vertical force sensing and lateral strain sensing into only one nanodevice, providing a feasible strategy for multimodal devices.

Implantable Multimodal Sensing Device for Simultaneous Imaging and Electrophysiological Recording of Mouse Brain Activity

Implantable Multimodal Sensing Device for Simultaneous Imaging and Electrophysiological Recording of Mouse Brain Activity

A multimodal sensing ring for quantification of scratch intensity

BackgroundAn objective measurement of chronic itch is necessary for improvements in patient care for numerous medical conditions. While wearables have shown promise for scratch detection, they are currently unable to estimate scratch intensity, preventing a comprehensive understanding of the effect of itch on an individual.MethodsIn this work, we present a framework for the estimation of scratch intensity in addition to the detection of scratch. This is accomplished with a multimodal ring device, consisting of an accelerometer and a contact microphone, a pressure-sensitive tablet for capturing ground truth intensity values, and machine learning algorithms for regression of scratch intensity on a 0–600 milliwatts (mW) power scale that can be mapped to a 0–10 continuous scale.ResultsWe evaluate the performance of our algorithms on 20 individuals using leave one subject out cross-validation and using data from 14 additional participants, we show that our algorithms achieve clinically-relevant discrimination of scratching intensity levels. By doing so, our device enables the quantification of the substantial variations in the interpretation of the 0–10 scale frequently utilized in patient self-reported clinical assessments.ConclusionsThis work demonstrates that a finger-worn device can provide multidimensional, objective, real-time measures for the action of scratching.

3D-printed epifluidic electronic skin for machine learning-powered multimodal health surveillance.

The amalgamation of wearable technologies with physiochemical sensing capabilities promises to create powerful interpretive and predictive platforms for real-time health surveillance. However, the construction of such multimodal devices is difficult to be implemented wholly by traditional manufacturing techniques for at-home personalized applications. Here, we present a universal semisolid extrusion-based three-dimensional printing technology to fabricate an epifluidic elastic electronic skin (e3-skin) with high-performance multimodal physiochemical sensing capabilities. We demonstrate that the e3-skin can serve as a sustainable surveillance platform to capture the real-time physiological state of individuals during regular daily activities. We also show that by coupling the information collected from the e3-skin with machine learning, we were able to predict an individual's degree of behavior impairments (i.e., reaction time and inhibitory control) after alcohol consumption. The e3-skin paves the path for future autonomous manufacturing of customizable wearable systems that will enable widespread utility for regular health monitoring and clinical applications.

Exploring Opportunities for Multimodality and Multiple Devices in Food Journaling

Digital food journaling can support personal goals, such as weight loss and developing healthy eating behaviors. However, traditional manual tracking demands great effort, often leading to lapses or abandonment. We explore opportunities for journaling with multiple input modalities and devices, leveraging people's daily interactions with a range of technologies. We report on an extended analysis of 15 participants' experiences with ModEat, a prototype supporting journaling with several input modalities on phone, computer, and voice assistants. Participants' modality and device preferences were largely influenced by their goals, but they frequently deviated from those preferences depending on device availability, perceived affordances, and characteristics of foods eaten. Participants rarely combined input modalities in entries, but some described that doing so allowed for more detailed journaling or serve as a placeholder for later. We discuss advantages and drawbacks of multimodal tracking and potential strategies for improving interactions.

Wearable detection of tonic seizures in childhood epilepsy: an exploratory cohort study.

To investigate the performance of a multimodal wearable device for the offline detection of tonic seizures (TS) in a pediatric childhood epilepsy cohort, with a focus on patients with Lennox-Gastaut syndrome. Parallel with prolonged video-electroencephalography (EEG), the Plug 'n Patch system, a multimodal wearable device using the Sensor Dot and replaceable electrode adhesives, was used to detect TS. Multiple biosignals were recorded: behind-the-ear EEG, surface electromyography, electrocardiography, and accelerometer/gyroscope. Biosignals were annotated blindly by a neurologist. Seizure characteristics were described, and performance was assessed by sensitivity, positive predictive value (PPV), F1 score, and false alarm rate (FAR) per hour. Performance was compared to seizure diaries kept by the caretaker. Ninety-nine TS were detected in 13 patients. Seven patients (54%) had Lennox-Gastaut syndrome and six patients (46%) had other forms of (developmental) epileptic encephalopathies or drug-resistant epilepsy. All but one patient had intellectual disability. Overall sensitivity was 41%, with a PPV of 9%, an F1 score of 14%, and a median FAR per hour of 0.75. Performance increased to an F1 score of 66% for nightly seizures lasting at least 10 s (sensitivity 66%, PPV 66%) and 71% for nightly seizures lasting at least 20 s (sensitivity 62%, PPV 82%). For these seizures there were no false alarms in 10 of 13 patients. Sensitivity of seizure diaries reached a maximum of 52% for prolonged (≥20 s) nightly seizures, even though caretakers slept in the same room. We showed that it is feasible to use a multimodal wearable device with multiple adhesive sites in children with epilepsy and intellectual disability. For prolonged nightly seizures, offline manual detection of TS outperformed seizure diaries. The recognition of seizure-specific signatures using multiple modalities can help in the development of automated TS detection algorithms.

Design and Research of Multimodal Fusion Feedback Device Based on Virtual Interactive System

This paper proposes a kinesthetic–tactile fusion feedback system based on virtual interaction. Combining the results of human fingertip deformation characteristics analysis and an upper limb motion mechanism, a fingertip tactile feedback device and an arm kinesthetic feedback device are designed and analyzed for blind instructors. In order to verify the effectiveness of the method, virtual touch experiments are established through the mapping relationship between the master–slave and virtual end. The results showed that the average recognition rate of virtual objects is 79.58%, and the recognition speed is improved by 41.9% compared with the one without force feedback, indicating that the kinesthetic–tactile feedback device can provide more haptic perception information in virtual feedback and improve the recognition rate of haptic perception.

Wrist-worn smartwatch and predictive models for seizures.

This study was undertaken to describe extracerebral biosignal characteristics of overall and various seizure types as compared with baseline physical activities using multimodal devices (Empatica E4); develop predictive models for overall and each seizure type; and assess diagnostic performance of each model. We prospectively recruited patients with focal epilepsy who were admitted to the epilepsy monitoring unit for presurgical evaluation during January to December 2020. All study participants were simultaneously applied gold standard long-term video-electroencephalographic (EEG) monitoring and an index test, E4. Two certified epileptologists independently determined whether captured events were seizures and then indicated ictal semiology and EEG information. Both were blind to multimodal biosignal findings detected by E4. Biosignals during 5-min epochs of both seizure events and baseline were collected and compared. Predictive models for occurrence overall and of each seizure type were developed using a generalized estimating equation. Diagnostic performance of each model was then assessed. Thirty patients had events recorded and were recruited for analysis. One hundred eight seizure events and 120 baseline epochs were collected. Heart rate (HR), acceleration (ACC), and electrodermal activity (EDA) but not temperature were significantly elevated during seizures. Cluster analysis showed trends of greatest elevation of HR and ACC in bilateral tonic-clonic seizures (BTCs), as compared with non-BTCs and isolated auras. HR and ACC were independent predictors for overall seizure types, BTCs, and non-BTCs, whereas only HR was a predictor for isolated aura. Diagnostic performance including sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve of the predictive model for overall seizures were 77.78%, 60%, and .696 (95% confidence interval = .628-.764), respectively. Multimodal extracerebral biosignals (HR, ACC, EDA) detected by a wrist-worn smartwatch can help differentiate between epileptic seizures and normal physical activities. It would be worthwhile to implement our predictive algorithms in commercial seizure detection devices. However, larger studies to externally validate our predictive models are required.

A Wearable Multimodal Wireless Sensing System for Respiratory Monitoring and Analysis.

Wireless sensing systems are required for continuous health monitoring and data collection. It allows for patient data collection in real time rather than through time-consuming and expensive hospital or lab visits. This technology employs wearable sensors, signal processing, and wireless data transfer to remotely monitor patients' health. The research offers a novel approach to providing primary diagnostics remotely with a digital health system for monitoring pulmonary health status using a multimodal wireless sensor device. The technology uses a compact wearable with new integration of acoustics and biopotentials sensors to monitor cardiovascular and respiratory activity to provide comprehensive and fast health status monitoring. Furthermore, the small wearable sensor size may stick to human skin and record heart and lung activities to monitor respiratory health. This paper proposes a sensor data fusion method of lung sounds and cardiograms for potential real-time respiration pattern diagnostics, including respiratory episodes like low tidal volume and coughing. With a p-value of 0.003 for sound signals and 0.004 for electrocardiogram (ECG), preliminary tests demonstrated that it was possible to detect shallow breathing and coughing at a meaningful level.

‘It sounds a little cool’

Abstract Social media platforms such as YouTube have become increasingly popular for language teaching and learning. Despite adequate research on the use of YouTube for educational purposes, it is necessary to explore the verbal and non-verbal features YouTubers deploy, as in Taiwan, to construct online discourse in a multilingual context. Using the Appraisal Theory framework, this study analyses the evaluative practices in three Taiwan-based English-teaching videos. The results reveal that YouTubers made evaluations fairly frequently and used specific multimodal devices for evaluation in language-teaching videos, such as expressions of judgement, disclaim, and focus, and gestures such as beats and pointing. The evaluation was found to serve genre-specific functions, including explaining pedagogical content, making meta-pragmatic comments about language use, marking the opening and closing of the video, and promoting products or services. The findings have implications for research on appraisal, social media pragmatics, and online language teaching practices.

Multimodal optical device to study dynamics of drying process

Imaging and quantification of the drying process find applications in many fields, including the drying of paints. Measurement of different parameters during the drying process leads to accurate identification of the state of the sample under investigation. We propose a multimodal optical technique combining spectroscopy, speckle correlation, and digital holography to analyze and quantify drying process. The developed device is tested in the identification of drying phases of paints. In the developed device, digital holographic interferometry is employed to obtain spatial variation of deformation on the surface coated with paint. Although digital holography is an efficient tool to study drying it is limited to the latter stages of the process. To study initial and intermediate stages laser speckle correlation and spectroscopy are integrated with digital holography. The spectrometer uses an LED source to acquire the reflectance spectrum. The reflectance increases with time and saturates as the water content of paint naturally evaporates. It was observed that this saturation occurs in intermediate stages of the process. To further analyze the drying stages, speckle images of the paint surface are also acquired. The speckle intensity correlation varied from low to high with drying. The combination of laser speckle, digital holography and spectroscopy complement one another and enables the study of all stages of drying process. To the best of our knowledge this is the first time such a multimodal optical device is developed for the complete analysis of drying process.

A direct comparison of sound and vibration as sources of stimulation for a sensory substitution glove

Sensory substitution devices (SSDs) facilitate the detection of environmental information through enhancement of touch and/or hearing capabilities. Research has demonstrated that several tasks can be successfully completed using acoustic, vibrotactile, and multimodal devices. The suitability of a substituting modality is also mediated by the type of information required to perform the specific task. The present study tested the adequacy of touch and hearing in a grasping task by utilizing a sensory substitution glove. The substituting modalities inform, through increases in stimulation intensity, about the distance between the fingers and the objects. A psychophysical experiment of magnitude estimation was conducted. Forty blindfolded sighted participants discriminated equivalently the intensity of both vibrotactile and acoustic stimulation, although they experienced some difficulty with the more intense stimuli. Additionally, a grasping task involving cylindrical objects of varying diameters, distances and orientations was performed. Thirty blindfolded sighted participants were divided into vibration, sound, or multimodal groups. High performance was achieved (84% correct grasps) with equivalent success rate between groups. Movement variables showed more precision and confidence in the multimodal condition. Through a questionnaire, the multimodal group indicated their preference for using a multimodal SSD in daily life and identified vibration as their primary source of stimulation. These results demonstrate that there is an improvement in performance with specific-purpose SSDs, when the necessary information for a task is identified and coupled with the delivered stimulation. Furthermore, the results suggest that it is possible to achieve functional equivalence between substituting modalities when these previous steps are met.

A switchable multi-wavelength mode-locked fiber laser based on a multi-mode interference device

A switchable multi-wavelength, passively mode-locked fiber laser in the 1 μm regime is demonstrated in this paper. The key principles of working include the nonlinear polarization rotation (NPR) mechanism for the mode-locked pulse generation and a single mode-multimode-single mode (SMS) structure as the spectral filter. The SMS structure is coiled on the paddles of a polarization controller (PC). Stable mode-locking operation is achieved at the fundamental repetition rate of 7.97 MHz. The pulse duration is 429 ps at the pump level of 216 mW, with the dual-wavelength laser emitting at 1037.86 nm and 1045.72 nm. By properly tuning the paddles of PCs, multi-wavelength mode-locked laser spectra can be observed switching from triple- to sextuple-wavelength, with the emission bandwidth of 27.6 nm from 1035.6 nm to 1063.2 nm.

Representational Similarity Analysis for Tracking Neural Correlates of Haptic Learning on a Multimodal Device.

A goal of wearable haptic devices has been to enable haptic communication, where individuals learn to map information typically processed visually or aurally to haptic cues via a process of cross-modal associative learning. Neural correlates have been used to evaluate haptic perception and may provide a more objective approach to assess association performance than more commonly used behavioral measures of performance. In this article, we examine Representational Similarity Analysis (RSA) of electroencephalography (EEG) as a framework to evaluate how the neural representation of multifeatured haptic cues changes with association training. We focus on the first phase of cross-modal associative learning, perception of multimodal cues. A participant learned to map phonemes to multimodal haptic cues, and EEG data were acquired before and after training to create neural representational spaces that were compared to theoretical models. Our perceptual model showed better correlations to the neural representational space before training, while the feature-based model showed better correlations with the post-training data. These results suggest that training may lead to a sharpening of the sensory response to haptic cues. Our results show promise that an EEG-RSA approach can capture a shift in the representational space of cues, as a means to track haptic learning.

Research on Multi -mode Power Generation Devices based on Wave Energy

This paper mainly studies a multi-mode power generation device based on wave energy, which is mainly composed of power generation device, energy storage device, monitoring device, through the use of electromagnetic machinery, piezoelectric ceramics, hydraulic system in a variety of ways to generate electricity, and then the energy storage device stable output, is a kind of power generation system will be converted into electrical energy device, to achieve high efficiency conversion of wave energy. Each part of the project is innovative and practical, which has high application value in ocean power generation. Compared with some traditional power generation devices, this device uses a new type of energy, ocean wave energy, which is a pollution-free, clean and renewable new energy. Wave energy has high flow density, huge reserves and wide distribution, which is the main direction of the development of ocean energy utilization in the future. It will make positive contributions to Marine construction, economic development and infrastructure construction of countries and regions along the Belt and Road.

Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action

Recent quantum technologies have established precise quantum control of various microscopic systems using electromagnetic waves. Interfaces based on cryogenic cavity electro-optic systems are particularly promising, due to the direct interaction between microwave and optical fields in the quantum regime. Quantum optical control of superconducting microwave circuits has been precluded so far due to the weak electro-optical coupling as well as quasi-particles induced by the pump laser. Here we report the coherent control of a superconducting microwave cavity using laser pulses in a multimode electro-optical device at millikelvin temperature with near-unity cooperativity. Both the stationary and instantaneous responses of the microwave and optical modes comply with the coherent electro-optical interaction, and reveal only minuscule amount of excess back-action with an unanticipated time delay. Our demonstration enables wide ranges of applications beyond quantum transductions, from squeezing and quantum non-demolition measurements of microwave fields, to entanglement generation and hybrid quantum networks.

A 16-channel loop array for in vivo macaque whole-brain imaging at 7 T

Combining multimodal approaches with functional magnetic resonance imaging (fMRI) has catapulted the research on brain circuitries of non-human primates (NHPs) into a new era. However, many studies are constrained by a lack of appropriate RF coils. In this study, a single loop transmit and 16-channel receive array coil was constructed for brain imaging of macaques at 7 Tesla (7 T). The 16 receive channels were mounted on a 3D-printed helmet-shaped form closely fitting the macaque head, with fourteen openings arranged for multimodal devices around the cortical regions. Coil performance was evaluated by quantifying and comparing signal-to-noise ratio (SNR) maps, noise correlations, g-factor maps and flip-angle maps with a 28-channel commercial knee coil. The in vivo results suggested that the macaque coil has higher SNR in cortical regions and better acceleration ability in parallel imaging, which may benefit revealing mesoscale organizations in the brain.