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1.
Sensors (Basel) ; 24(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38894070

RESUMO

To provide diverse in-home services like elderly care, versatile activity recognition technology is essential. Radio-based methods, including WiFi CSI, RFID, and backscatter communication, are preferred due to their minimal privacy intrusion, reduced physical burden, and low maintenance costs. However, these methods face challenges, including environmental dependence, proximity limitations between the device and the user, and untested accuracy amidst various radio obstacles such as furniture, appliances, walls, and other radio waves. In this paper, we propose a frequency-shift backscatter tag-based in-home activity recognition method and test its feasibility in a near-real residential setting. Consisting of simple components such as antennas and switches, these tags facilitate ultra-low power consumption and demonstrate robustness against environmental noise because a context corresponding to a tag can be obtained by only observing frequency shifts. We implemented a sensing system consisting of SD-WiFi, a software-defined WiFi AP, and physical switches on backscatter tags tailored for detecting the movements of daily objects. Our experiments demonstrate that frequency shifts by tags can be detected within a 2 m range with 72% accuracy under the line of sight (LoS) conditions and achieve a 96.0% accuracy (F-score) in recognizing seven typical daily living activities with an appropriate receiver/transmitter layout. Furthermore, in an additional experiment, we confirmed that increasing the number of overlaying packets enables frequency shift-detection even without LoS at distances of 3-5 m.


Assuntos
Atividades Cotidianas , Tecnologia sem Fio , Humanos , Ondas de Rádio , Dispositivo de Identificação por Radiofrequência/métodos
2.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894166

RESUMO

The healthcare industry went through reformation by integrating the Internet of Medical Things (IoMT) to enable data harnessing by transmission mediums from different devices, about patients to healthcare staff devices, for further analysis through cloud-based servers for proper diagnosis of patients, yielding efficient and accurate results. However, IoMT technology is accompanied by a set of drawbacks in terms of security risks and vulnerabilities, such as violating and exposing patients' sensitive and confidential data. Further, the network traffic data is prone to interception attacks caused by a wireless type of communication and alteration of data, which could cause unwanted outcomes. The advocated scheme provides insight into a robust Intrusion Detection System (IDS) for IoMT networks. It leverages a honeypot to divert attackers away from critical systems, reducing the attack surface. Additionally, the IDS employs an ensemble method combining Logistic Regression and K-Nearest Neighbor algorithms. This approach harnesses the strengths of both algorithms to improve attack detection accuracy and robustness. This work analyzes the impact, performance, accuracy, and precision outcomes of the used model on two IoMT-related datasets which contain multiple attack types such as Man-In-The-Middle (MITM), Data Injection, and Distributed Denial of Services (DDOS). The yielded results showed that the proposed ensemble method was effective in detecting intrusion attempts and classifying them as attacks or normal network traffic, with a high accuracy of 92.5% for the first dataset and 99.54% for the second dataset and a precision of 96.74% for the first dataset and 99.228% for the second dataset.


Assuntos
Algoritmos , Segurança Computacional , Atenção à Saúde , Internet das Coisas , Humanos , Tecnologia sem Fio , Computação em Nuvem , Confidencialidade
3.
Sensors (Basel) ; 24(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38894225

RESUMO

The Internet of Things (IoT) is a growing network of interconnected devices used in transportation, finance, public services, healthcare, smart cities, surveillance, and agriculture. IoT devices are increasingly integrated into mobile assets like trains, cars, and airplanes. Among the IoT components, wearable sensors are expected to reach three billion by 2050, becoming more common in smart environments like buildings, campuses, and healthcare facilities. A notable IoT application is the smart campus for educational purposes. Timely notifications are essential in critical scenarios. IoT devices gather and relay important information in real time to individuals with special needs via mobile applications and connected devices, aiding health-monitoring and decision-making. Ensuring IoT connectivity with end users requires long-range communication, low power consumption, and cost-effectiveness. The LPWAN is a promising technology for meeting these needs, offering a low cost, long range, and minimal power use. Despite their potential, mobile IoT and LPWANs in healthcare, especially for emergency response systems, have not received adequate research attention. Our study evaluated an LPWAN-based emergency response system for visually impaired individuals on the Hazara University campus in Mansehra, Pakistan. Experiments showed that the LPWAN technology is reliable, with 98% reliability, and suitable for implementing emergency response systems in smart campus environments.


Assuntos
Internet das Coisas , Humanos , Aplicativos Móveis , Tecnologia sem Fio
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 330-334, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863103

RESUMO

Pulse rate and blood oxygen levels are crucial physiological parameters that reflect physiological and pathological information within the human body. The system designs a wireless pulse wave monitoring system utilizing a flexible reflective probe and the AFE4490, which is capable of monitoring pulse wave and blood oxygen levels on the human forehead. The system is predominantly based on a reflective flexible probe, the AFE4490, a power supply module, a control microcontroller unit (MCU), and a Wi-Fi module. Post-processing by a slave computer, the collected pulse wave data is wirelessly transmitted to a smartphone. The real-time pulse waveform, pulse rate, and blood oxygen levels are displayed on an application. Following relevant tests and verifications, the system can accurately detect pulse wave signals, meet the requirements for wearable technology, and possesses significant market application potential.


Assuntos
Tecnologia sem Fio , Monitorização Fisiológica/instrumentação , Humanos , Análise de Onda de Pulso/instrumentação , Smartphone , Frequência Cardíaca , Oxigênio , Processamento de Sinais Assistido por Computador , Dispositivos Eletrônicos Vestíveis
5.
PLoS One ; 19(6): e0304386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865334

RESUMO

Rotating Polarization Wave (RPW) is a novel Low Power Wide Area Networks (LPWAN) technology for robust connectivity and extended coverage area as compared to other LPWAN technologies such as LoRa and Sigfox when no error detection and correction is employed. Since, IoT and Machine-to-Machine (M2M) communication demand high reliability, RPW with error correction can significantly enhance the communication reliability for critical IoT and M2M applications. Therefore, this study investigates the performance of RPW with single bit error detection and correction using Hamming codes to avoid substantial overhead. Hamming (7,4) coded RPW shows a remarkable improvement of more than 40% in error performance compared to uncoded RPW thereby making it a suitable candidate for IoT and M2M applications. Error performance of coded RPW outperforms coded Chirp Spread Spectrum (CSS) modulation used in LoRa under multipath conditions by 51%, demonstrating superior adaptability and robustness under dynamic channel conditions. These findings provide valuable insights into the ongoing developments in wireless communication systems whilst reporting Q-RPW model as a new and effective method to address the needs of developing LPWAN and IoT ecosystems.


Assuntos
Tecnologia sem Fio , Redes de Comunicação de Computadores , Humanos
6.
Sci Adv ; 10(24): eadn5195, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38865448

RESUMO

Anatomy-specific radio frequency receive coil arrays routinely adopted in magnetic resonance imaging (MRI) for signal acquisition are commonly burdened by their bulky, fixed, and rigid configurations, which may impose patient discomfort, bothersome positioning, and suboptimal sensitivity in certain situations. Herein, leveraging coaxial cables' inherent flexibility and electric field confining property, we present wireless, ultralightweight, coaxially shielded, passive detuning MRI coils achieving a signal-to-noise ratio comparable to or surpassing that of commercially available cutting-edge receive coil arrays with the potential for improved patient comfort, ease of implementation, and substantially reduced costs. The proposed coils demonstrate versatility by functioning both independently in form-fitting configurations, closely adapting to relatively small anatomical sites, and collectively by inductively coupling together as metamaterials, allowing for extension of the field of view of their coverage to encompass larger anatomical regions without compromising coil sensitivity. The wireless, coaxially shielded MRI coils reported herein pave the way toward next-generation MRI coils.


Assuntos
Imageamento por Ressonância Magnética , Tecnologia sem Fio , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/instrumentação , Tecnologia sem Fio/instrumentação , Humanos , Desenho de Equipamento , Razão Sinal-Ruído , Imagens de Fantasmas
7.
PLoS One ; 19(6): e0304983, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38829849

RESUMO

This paper introduces a two-element antenna array with dual-sense circular polarization, wideband operation, and high isolation characteristics. The antenna consists of two conventional truncated corner patches and an extra layer of metasurface (MS) located above the radiating patches. The overall dimensions of the proposed antenna are 0.92 λ0 × 0.73 λ0 × 0.05 λ0 and the element spacings are 0.02 λ0 and 0.39 λ0 with respect to edge-to-edge and center-to-center spacings. For validation, measurements on a fabricated antenna prototype are carried out. The measured data demonstrate that the presented MS-based antenna has a wide operating bandwidth of 14.5% with high isolation of better than 26 dB. The excellent performance could be concluded from the results of the investigation, which indicates that the proposed MS-based antenna could be a good candidate for multiple-input multiple-output (MIMO) and full-duplex applications.


Assuntos
Desenho de Equipamento , Tecnologia sem Fio/instrumentação
8.
Curr Biol ; 34(11): R536-R539, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38834026

RESUMO

A new study leads the way to a more ethical and ethologically meaningful way of investigating brain functions of complex behaviors in social animals.


Assuntos
Neurociências , Primatas , Comportamento Social , Animais , Primatas/fisiologia , Encéfalo/fisiologia , Tecnologia sem Fio/instrumentação , Comportamento Animal/fisiologia
9.
Biosens Bioelectron ; 260: 116421, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838572

RESUMO

Wearable technologies are becoming pervasive in our society, and their development continues to accelerate the untapped potential of continuous and ubiquitous sensing, coupled with big data analysis and interpretation, has only just begun to unfold. However, existing wearable devices are still bulky (mainly due to batteries and electronics) and have suboptimal skin contact. In this work, we propose a novel approach based on a sensor network produced through inkjet printing of nanofunctional inks onto a semipermeable substrate. This network enables real-time monitoring of critical physiological parameters, including temperature, humidity, and muscle contraction. Remarkably, our system operates under battery-free and wireless near-field communication (NFC) technology for data readout via smartphones. Moreover, two of the three sensors were integrated onto a naturally adhesive bioinspired membrane. This membrane, developed using an eco-friendly, high-throughput process, draws inspiration from the remarkable adhesive properties of mussel-inspired molecules. The resulting ultra-conformable membrane adheres effortlessly to the skin, ensuring reliable and continuous data collection. The urgency of effective monitoring systems cannot be overstated, especially in the context of rising heat stroke incidents attributed to climate change and high-risk occupations. Heat stroke manifests as elevated skin temperature, lack of sweating, and seizures. Swift intervention is crucial to prevent progression to coma or fatality. Therefore, our proposed system holds immense promise for the monitoring of these parameters on the field, benefiting both the general population and high-risk workers, such as firefighters.


Assuntos
Técnicas Biossensoriais , Bivalves , Golpe de Calor , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Humanos , Tecnologia sem Fio/instrumentação , Técnicas Biossensoriais/instrumentação , Animais , Golpe de Calor/prevenção & controle , Bivalves/química , Adesivos/química , Membranas Artificiais , Desenho de Equipamento , Smartphone
10.
Nature ; 630(8015): 84-90, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840015

RESUMO

Direct and precise monitoring of intracranial physiology holds immense importance in delineating injuries, prognostication and averting disease1. Wired clinical instruments that use percutaneous leads are accurate but are susceptible to infection, patient mobility constraints and potential surgical complications during removal2. Wireless implantable devices provide greater operational freedom but include issues such as limited detection range, poor degradation and difficulty in size reduction in the human body3. Here we present an injectable, bioresorbable and wireless metastructured hydrogel (metagel) sensor for ultrasonic monitoring of intracranial signals. The metagel sensors are cubes 2 × 2 × 2 mm3 in size that encompass both biodegradable and stimulus-responsive hydrogels and periodically aligned air columns with a specific acoustic reflection spectrum. Implanted into intracranial space with a puncture needle, the metagel deforms in response to physiological environmental changes, causing peak frequency shifts of reflected ultrasound waves that can be wirelessly measured by an external ultrasound probe. The metagel sensor can independently detect intracranial pressure, temperature, pH and flow rate, realize a detection depth of 10 cm and almost fully degrade within 18 weeks. Animal experiments on rats and pigs indicate promising multiparametric sensing performances on a par with conventional non-resorbable wired clinical benchmarks.


Assuntos
Hidrogéis , Pressão Intracraniana , Tecnologia sem Fio , Animais , Tecnologia sem Fio/instrumentação , Ratos , Suínos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Hidrogéis/química , Masculino , Ondas Ultrassônicas , Feminino , Concentração de Íons de Hidrogênio , Injeções/instrumentação , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Temperatura , Implantes Absorvíveis , Ratos Sprague-Dawley
11.
Nature ; 629(8014): 1047-1054, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38778108

RESUMO

Wireless modules that provide telecommunications and power-harvesting capabilities enabled by radio-frequency (RF) electronics are vital components of skin-interfaced stretchable electronics1-7. However, recent studies on stretchable RF components have demonstrated that substantial changes in electrical properties, such as a shift in the antenna resonance frequency, occur even under relatively low elastic strains8-15. Such changes lead directly to greatly reduced wireless signal strength or power-transfer efficiency in stretchable systems, particularly in physically dynamic environments such as the surface of the skin. Here we present strain-invariant stretchable RF electronics capable of completely maintaining the original RF properties under various elastic strains using a 'dielectro-elastic' material as the substrate. Dielectro-elastic materials have physically tunable dielectric properties that effectively avert frequency shifts arising in interfacing RF electronics. Compared with conventional stretchable substrate materials, our material has superior electrical, mechanical and thermal properties that are suitable for high-performance stretchable RF electronics. In this paper, we describe the materials, fabrication and design strategies that serve as the foundation for enabling the strain-invariant behaviour of key RF components based on experimental and computational studies. Finally, we present a set of skin-interfaced wireless healthcare monitors based on strain-invariant stretchable RF electronics with a wireless operational distance of up to 30 m under strain.


Assuntos
Elasticidade , Eletrônica , Desenho de Equipamento , Ondas de Rádio , Pele , Estresse Mecânico , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Humanos , Eletrônica/instrumentação , Tecnologia sem Fio/instrumentação , Monitorização Fisiológica/instrumentação
12.
Curr Opin Crit Care ; 30(3): 275-282, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690957

RESUMO

PURPOSE OF REVIEW: Wearable wireless sensors for continuous vital signs monitoring (CVSM) offer the potential for early identification of patient deterioration, especially in low-intensity care settings like general wards. This study aims to review advances in wearable CVSM - with a focus on the general ward - highlighting the technological characteristics of CVSM systems, user perspectives and impact on patient outcomes by exploring recent evidence. RECENT FINDINGS: The accuracy of wearable sensors measuring vital signs exhibits variability, especially notable in ambulatory patients within hospital settings, and standard validation protocols are lacking. Usability of CMVS systems is critical for nurses and patients, highlighting the need for easy-to-use wearable sensors, and expansion of the number of measured vital signs. Current software systems lack integration with hospital IT infrastructures and workflow automation. Imperative enhancements involve nurse-friendly, less intrusive alarm strategies, and advanced decision support systems. Despite observed reductions in ICU admissions and Rapid Response Team calls, the impact on patient outcomes lacks robust statistical significance. SUMMARY: Widespread implementation of CVSM systems on the general ward and potentially outside the hospital seems inevitable. Despite the theoretical benefits of CVSM systems in improving clinical outcomes, and supporting nursing care by optimizing clinical workflow efficiency, the demonstrated effects in clinical practice are mixed. This review highlights the existing challenges related to data quality, usability, implementation, integration, interpretation, and user perspectives, as well as the need for robust evidence to support their impact on patient outcomes, workflow and cost-effectiveness.


Assuntos
Sinais Vitais , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Tecnologia sem Fio/instrumentação
13.
Nat Commun ; 15(1): 4035, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740742

RESUMO

Rapid and accurate detection of respiratory virus aerosols is highlighted for virus surveillance and infection control. Here, we report a wireless immunoassay technology for fast (within 10 min), on-site (wireless and battery-free), and sensitive (limit of detection down to fg/L) detection of virus antigens in aerosols. The wireless immunoassay leverages the immuno-responsive hydrogel-modulated radio frequency resonant sensor to capture and amplify the recognition of virus antigen, and flexible readout network to transduce the immuno bindings into electrical signals. The wireless immunoassay achieves simultaneous detection of respiratory viruses such as severe acute respiratory syndrome coronavirus 2, influenza A H1N1 virus, and respiratory syncytial virus for community infection surveillance. Direct detection of unpretreated clinical samples further demonstrates high accuracy for diagnosis of respiratory virus infection. This work provides a sensitive and accurate immunoassay technology for on-site virus detection and disease diagnosis compatible with wearable integration.


Assuntos
Hidrogéis , Vírus da Influenza A Subtipo H1N1 , SARS-CoV-2 , Tecnologia sem Fio , Imunoensaio/métodos , Imunoensaio/instrumentação , Humanos , Hidrogéis/química , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Tecnologia sem Fio/instrumentação , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Aerossóis , COVID-19/diagnóstico , COVID-19/virologia , COVID-19/imunologia , Antígenos Virais/imunologia , Antígenos Virais/análise , Vírus Sinciciais Respiratórios/imunologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Limite de Detecção
14.
Biosens Bioelectron ; 258: 116298, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38701537

RESUMO

Wireless activation of the enteric nervous system (ENS) in freely moving animals with implantable optogenetic devices offers a unique and exciting opportunity to selectively control gastrointestinal (GI) transit in vivo, including the gut-brain axis. Programmed delivery of light to targeted locations in the GI-tract, however, poses many challenges not encountered within the central nervous system (CNS). We report here the development of a fully implantable, battery-free wireless device specifically designed for optogenetic control of the GI-tract, capable of generating sufficient light over large areas to robustly activate the ENS, potently inducing colonic motility ex vivo and increased propulsion in vivo. Use in in vivo studies reveals unique stimulation patterns that increase expulsion of colonic content, likely mediated in part by activation of an extrinsic brain-gut motor pathway, via pelvic nerves. This technology overcomes major limitations of conventional wireless optogenetic hardware designed for the CNS, providing targeted control of specific neurochemical classes of neurons in the ENS and brain-gut axis, for direct modulation of GI-transit and associated behaviours in freely moving animals.


Assuntos
Sistema Nervoso Entérico , Optogenética , Tecnologia sem Fio , Animais , Optogenética/instrumentação , Sistema Nervoso Entérico/fisiologia , Camundongos , Tecnologia sem Fio/instrumentação , Eixo Encéfalo-Intestino/fisiologia , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Encéfalo/fisiologia , Camundongos Endogâmicos C57BL
15.
Biomed Eng Online ; 23(1): 48, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760808

RESUMO

Monitoring of ingestive activities is critically important for managing the health and wellness of individuals with various health conditions, including the elderly, diabetics, and individuals seeking better weight control. Monitoring swallowing events can be an ideal surrogate for developing streamlined methods for effective monitoring and quantification of eating or drinking events. Swallowing is an essential process for maintaining life. This seemingly simple process is the result of coordinated actions of several muscles and nerves in a complex fashion. In this study, we introduce automated methods for the detection and quantification of various eating and drinking activities. Wireless surface electromyography (sEMG) was used to detect chewing and swallowing from sEMG signals obtained from the sternocleidomastoid muscle, in addition to signals obtained from a wrist-mounted IMU sensor. A total of 4675 swallows were collected from 55 participants in the study. Multiple methods were employed to estimate bolus volumes in the case of fluid intake, including regression and classification models. Among the tested models, neural networks-based regression achieved an R2 of 0.88 and a root mean squared error of 0.2 (minimum bolus volume was 10 ml). Convolutional neural networks-based classification (when considering each bolus volume as a separate class) achieved an accuracy of over 99% using random cross-validation and around 66% using cross-subject validation. Multiple classification methods were also used for solid bolus type detection, including SVM and decision trees (DT), which achieved an accuracy above 99% with random validation and above 94% in cross-subject validation. Finally, regression models with both random and cross-subject validation were used for estimating the solid bolus volume with an R2 value that approached 1 and root mean squared error values as low as 0.00037 (minimum solid bolus weight was 3 gm). These reported results lay the foundation for a cost-effective and non-invasive method for monitoring swallowing activities which can be extremely beneficial in managing various chronic health conditions, such as diabetes and obesity.


Assuntos
Deglutição , Eletromiografia , Humanos , Deglutição/fisiologia , Masculino , Feminino , Automação , Processamento de Sinais Assistido por Computador , Adulto , Redes Neurais de Computação , Tecnologia sem Fio
16.
Science ; 384(6699): 1023-1030, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38815037

RESUMO

Seamless interfaces between electronic devices and biological tissues stand to revolutionize disease diagnosis and treatment. However, biological and biomechanical disparities between synthetic materials and living tissues present challenges at bioelectrical signal transduction interfaces. We introduce the active biointegrated living electronics (ABLE) platform, encompassing capabilities across the biogenic, biomechanical, and bioelectrical properties simultaneously. The living biointerface, comprising a bioelectronics layout and a Staphylococcus epidermidis-laden hydrogel composite, enables multimodal signal transduction at the microbial-mammalian nexus. The extracellular components of the living hydrogels, prepared through thermal release of naturally occurring amylose polymer chains, are viscoelastic, capable of sustaining the bacteria with high viability. Through electrophysiological recordings and wireless probing of skin electrical impedance, body temperature, and humidity, ABLE monitors microbial-driven intervention in psoriasis.


Assuntos
Hidrogéis , Psoríase , Pele , Staphylococcus epidermidis , Animais , Humanos , Camundongos , Temperatura Corporal , Impedância Elétrica , Eletrônica , Umidade , Hidrogéis/química , Inflamação/microbiologia , Inflamação/terapia , Pele/microbiologia , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Psoríase/microbiologia , Psoríase/terapia , Camundongos Knockout , Receptor 2 Toll-Like/genética
17.
Nat Commun ; 15(1): 4597, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816464

RESUMO

Wireless capsule endoscopy (WCE) offers a non-invasive evaluation of the digestive system, eliminating the need for sedation and the risks associated with conventional endoscopic procedures. Its significance lies in diagnosing gastrointestinal tissue irregularities, especially in the small intestine. However, existing commercial WCE devices face limitations, such as the absence of autonomous lesion detection and treatment capabilities. Recent advancements in micro-electromechanical fabrication and computational methods have led to extensive research in sophisticated technology integration into commercial capsule endoscopes, intending to supersede wired endoscopes. This Review discusses the future requirements for intelligent capsule robots, providing a comparative evaluation of various methods' merits and disadvantages, and highlighting recent developments in six technologies relevant to WCE. These include near-field wireless power transmission, magnetic field active drive, ultra-wideband/intrabody communication, hybrid localization, AI-based autonomous lesion detection, and magnetic-controlled diagnosis and treatment. Moreover, we explore the feasibility for future "capsule surgeons".


Assuntos
Endoscopia por Cápsula , Tecnologia sem Fio , Endoscopia por Cápsula/métodos , Endoscopia por Cápsula/instrumentação , Humanos , Tecnologia sem Fio/instrumentação , Cápsulas Endoscópicas , Robótica/instrumentação
18.
Sci Adv ; 10(22): eadn0260, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820150

RESUMO

Biodegradable piezoelectric devices hold great promise in on-demand transient bioelectronics. Existing piezoelectric biomaterials, however, remain obstacles to the development of such devices due to difficulties in large-scale crystal orientation alignment and weak piezoelectricity. Here, we present a strategy for the synthesis of optimally orientated, self-aligned piezoelectric γ-glycine/polyvinyl alcohol (γ-glycine/PVA) films via an ultrasound-assisted process, guided by density functional theory. The first-principles calculations reveal that the negative piezoelectric effect of γ-glycine originates from the stretching and compression of glycine molecules induced by hydrogen bonding interactions. The synthetic γ-glycine/PVA films exhibit a piezoelectricity of 10.4 picocoulombs per newton and an ultrahigh piezoelectric voltage coefficient of 324 × 10-3 volt meters per newton. The biofilms are further developed into flexible, bioresorbable, wireless piezo-ultrasound electrotherapy devices, which are demonstrated to shorten wound healing by ~40% and self-degrade in preclinical wound models. These encouraging results offer reliable approaches for engineering piezoelectric biofilms and developing transient bioelectronics.


Assuntos
Biofilmes , Álcool de Polivinil , Tecnologia sem Fio , Álcool de Polivinil/química , Animais , Glicina/química , Cicatrização , Materiais Biocompatíveis/química , Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos
19.
Proc Natl Acad Sci U S A ; 121(22): e2404007121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768347

RESUMO

Sensations of heat and touch produced by receptors in the skin are of essential importance for perceptions of the physical environment, with a particularly powerful role in interpersonal interactions. Advances in technologies for replicating these sensations in a programmable manner have the potential not only to enhance virtual/augmented reality environments but they also hold promise in medical applications for individuals with amputations or impaired sensory function. Engineering challenges are in achieving interfaces with precise spatial resolution, power-efficient operation, wide dynamic range, and fast temporal responses in both thermal and in physical modulation, with forms that can extend over large regions of the body. This paper introduces a wireless, skin-compatible interface for thermo-haptic modulation designed to address some of these challenges, with the ability to deliver programmable patterns of enhanced vibrational displacement and high-speed thermal stimulation. Experimental and computational investigations quantify the thermal and mechanical efficiency of a vertically stacked design layout in the thermo-haptic stimulators that also supports real-time, closed-loop control mechanisms. The platform is effective in conveying thermal and physical information through the skin, as demonstrated in the control of robotic prosthetics and in interactions with pressure/temperature-sensitive touch displays.


Assuntos
Tato , Realidade Virtual , Tecnologia sem Fio , Humanos , Tecnologia sem Fio/instrumentação , Tato/fisiologia , Pele , Robótica/instrumentação , Robótica/métodos
20.
ACS Sens ; 9(5): 2346-2355, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38713172

RESUMO

Dopamine (DA) and serotonin (5-HT) are neurotransmitters that regulate a wide range of physiological and behavioral processes. Monitoring of both neurotransmitters with real-time analysis offers important insight into the mechanisms that shape animal behavior. However, bioelectronic tools to simultaneously monitor DA and 5-HT interactive dynamics in freely moving animals are underdeveloped. This is mainly due to the limited sensor sensitivity with miniaturized electronics. Here, we present a semi-implantable electrochemical device achieved by integrating a multi-surface-modified carbon fiber microelectrode with a miniaturized potentiostat module to detect DA and 5-HT in vivo with high sensitivity and selectivity. Specifically, carbon fiber microelectrodes were modified through electrochemical treatment and surface coatings to improve sensitivity, selectivity, and antifouling properties. A customized, lightweight potentiostat module was developed for untethered electrochemical measurements. Integrated with the microelectrode, the microsystem is compact (2.8 × 2.3 × 2.1 cm) to minimize its impacts on animal behavior and achieved simultaneous detection of DA and 5-HT with sensitivities of 48.4 and 133.0 nA/µM, respectively, within submicromolar ranges. The system was attached to the crayfish dorsal carapace, allowing electrode implantation into the heart of a crayfish to monitor DA and 5-HT dynamics, followed by drug injections. The semi-implantable biosensor system displayed a significant increase in oxidation peak currents after DA and 5-HT injections. The device successfully demonstrated the application for in vivo simultaneous monitoring of DA and 5-HT in the hemolymph (i.e., blood) of freely behaving crayfish underwater, yielding a valuable experimental tool to expand our understanding of the comodulation of DA and 5-HT.


Assuntos
Astacoidea , Dopamina , Técnicas Eletroquímicas , Microeletrodos , Serotonina , Animais , Dopamina/análise , Serotonina/análise , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Tecnologia sem Fio , Fibra de Carbono/química , Técnicas Biossensoriais/métodos
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