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1.
Sensors (Basel) ; 20(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906831

RESUMO

Social distancing and contact/exposure tracing are accepted to be critical strategies in the fight against the COVID-19 epidemic. They are both closely connected to the ability to reliably establish the degree of proximity between people in real-world environments. We proposed, implemented, and evaluated a wearable proximity sensing system based on an oscillating magnetic field that overcomes many of the weaknesses of the current state of the art Bluetooth based proximity detection. In this paper, we first described the underlying physical principle, proposed a protocol for the identification and coordination of the transmitter (which is compatible with the current smartphone-based exposure tracing protocols). Subsequently, the system architecture and implementation were described, finally an elaborate characterization and evaluation of the performance (both in systematic lab experiments and in real-world settings) were performed. Our work demonstrated that the proposed system is much more reliable than the widely-used Bluetooth-based approach, particularly when it comes to distinguishing between distances above and below the 2.0 m threshold due to the magnetic field's physical properties.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Campos Magnéticos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Dispositivos Eletrônicos Vestíveis , Busca de Comunicante , Infecções por Coronavirus/epidemiologia , Desenho de Equipamento , Humanos , Pneumonia Viral/epidemiologia , Smartphone , Distância Social , Dispositivos Eletrônicos Vestíveis/estatística & dados numéricos , Tecnologia sem Fio/instrumentação , Tecnologia sem Fio/estatística & dados numéricos
2.
Sensors (Basel) ; 20(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911861

RESUMO

Lung sounds acquired by stethoscopes are extensively used in diagnosing and differentiating respiratory diseases. Although an extensive know-how has been built to interpret these sounds and identify diseases associated with certain patterns, its effective use is limited to individual experience of practitioners. This user-dependency manifests itself as a factor impeding the digital transformation of this valuable diagnostic tool, which can improve patient outcomes by continuous long-term respiratory monitoring under real-life conditions. Particularly patients suffering from respiratory diseases with progressive nature, such as chronic obstructive pulmonary diseases, are expected to benefit from long-term monitoring. Recently, the COVID-19 pandemic has also shown the lack of respiratory monitoring systems which are ready to deploy in operational conditions while requiring minimal patient education. To address particularly the latter subject, in this article, we present a sound acquisition module which can be integrated into a dedicated garment; thus, minimizing the role of the patient for positioning the stethoscope and applying the appropriate pressure. We have implemented a diaphragm-less acousto-electric transducer by stacking a silicone rubber and a piezoelectric film to capture thoracic sounds with minimum attenuation. Furthermore, we benchmarked our device with an electronic stethoscope widely used in clinical practice to quantify its performance.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico/instrumentação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/fisiopatologia , Monitorização Ambulatorial/instrumentação , Pneumonia Viral/diagnóstico , Pneumonia Viral/fisiopatologia , Sons Respiratórios/diagnóstico , Sons Respiratórios/fisiopatologia , Estetoscópios , Dispositivos Eletrônicos Vestíveis , Acústica , Auscultação/instrumentação , Impedância Elétrica , Desenho de Equipamento , Humanos , Pandemias , Tecnologia de Sensoriamento Remoto/instrumentação , Processamento de Sinais Assistido por Computador , Transdutores , Tecnologia sem Fio/instrumentação
3.
Sensors (Basel) ; 20(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932848

RESUMO

The emerging wearable medical devices open up new opportunities for the provision of health services and promise to accelerate the development of novel telemedical services. The main objective of this study was to investigate the desirable features and applications of telemedical services for the Polish older adults delivered by wearable medical devices. The questionnaire study was conducted among 146 adult volunteers in two cohorts (C.1: <65 years vs. C.2: ≥65 years). The analysis was based on qualitative research and descriptive statistics. Comparisons were performed by Pearson's chi-squared test. The questionnaire, which was divided into three parts (1-socio-demographic data, needs, and behaviors; 2-health status; 3-telemedicine service awareness and device concept study), consisted of 37 open, semi-open, or closed questions. Two cohorts were analyzed (C.1: n = 77; mean age = 32 vs. C.2: n = 69; mean age = 74). The performed survey showed that the majority of respondents were unaware of the telemedical services (56.8%). A total of 62.3% of C.1 and 34.8% of C.2 declared their understanding of telemedical services. The 10.3% of correct explanations regarding telemedical service were found among all study participants. The most desirable feature was the detection of life-threatening and health-threatening situations (65.2% vs. 66.2%). The findings suggest a lack of awareness of telemedical services and the opportunities offered by wearable telemedical devices.


Assuntos
Telemedicina/instrumentação , Dispositivos Eletrônicos Vestíveis , Adulto , Idoso , Betacoronavirus , Estudos de Coortes , Infecções por Coronavirus/epidemiologia , Feminino , Geriatria/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Determinação de Necessidades de Cuidados de Saúde , Pandemias , Pneumonia Viral/epidemiologia , Polônia/epidemiologia , Tecnologia de Sensoriamento Remoto/instrumentação , Inquéritos e Questionários , Tecnologia sem Fio/instrumentação
4.
PLoS One ; 15(8): e0226052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756553

RESUMO

Children with movement impairments needing assistive devices for activities of daily living often require novel methods for controlling these devices. Body-machine interfaces, which rely on body movements, are particularly well-suited for children as they are non-invasive and have high signal-to-noise ratios. Here, we examined the use of a head-joystick to enable a child with congenital absence of all four limbs to control a seven degree-of-freedom robotic arm. Head movements were measured with a wireless inertial measurement unit and used to control a robotic arm to perform two functional tasks-a drinking task and a block stacking task. The child practiced these tasks over multiple sessions; a control participant performed the same tasks with a manual joystick. Our results showed that the child was able to successfully perform both tasks, with movement times decreasing by ~40-50% over 6-8 sessions of training. The child's performance with the head-joystick was also comparable to the control participant using a manual joystick. These results demonstrate the potential of using head movements for the control of high degree-of-freedom tasks in children with limited movement repertoire.


Assuntos
Robótica/instrumentação , Interface Usuário-Computador , Atividades Cotidianas , Adolescente , Cabeça/fisiologia , Movimentos da Cabeça/fisiologia , Humanos , Masculino , Movimento/fisiologia , Equipamentos de Autoajuda/tendências , Tecnologia sem Fio/instrumentação
5.
Proc Natl Acad Sci U S A ; 117(29): 16856-16863, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632002

RESUMO

Recent advances in soft materials and mechanics activate development of many new types of electrical medical implants. Electronic implants that provide exceptional functions, however, usually require more electrical power, resulting in shorter period of usages although many approaches have been suggested to harvest electrical power in human bodies by resolving the issues related to power density, biocompatibility, tissue damage, and others. Here, we report an active photonic power transfer approach at the level of a full system to secure sustainable electrical power in human bodies. The active photonic power transfer system consists of a pair of the skin-attachable photon source patch and the photovoltaic device array integrated in a flexible medical implant. The skin-attachable patch actively emits photons that can penetrate through live tissues to be captured by the photovoltaic devices in a medical implant. The wireless power transfer system is very simple, e.g., active power transfer in direct current (DC) to DC without extra circuits, and can be used for implantable medical electronics regardless of weather, covering by clothes, in indoor or outdoor at day and night. We demonstrate feasibility of the approach by presenting thermal and mechanical compatibility with soft live tissues while generating enough electrical power in live bodies through in vivo animal experiments. We expect that the results enable long-term use of currently available implants in addition to accelerating emerging types of electrical implants that require higher power to provide diverse convenient diagnostic and therapeutic functions in human bodies.


Assuntos
Coração Auxiliar , Fótons , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação , Animais , Frequência Cardíaca , Camundongos , Fenômenos Fisiológicos da Pele , Transdutores
6.
PLoS One ; 15(6): e0233266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492034

RESUMO

For gait classification, hoof-on and hoof-off events are fundamental locomotion characteristics of interest. These events can be measured with inertial measurement units (IMUs) which measure the acceleration and angular velocity in three directions. The aim of this study was to present two algorithms for automatic detection of hoof-events from the acceleration and angular velocity signals measured by hoof-mounted IMUs in walk and trot on a hard surface. Seven Warmblood horses were equipped with two wireless IMUs, which were attached to the lateral wall of the right front (RF) and hind (RH) hooves. Horses were walked and trotted on a lead over a force plate for internal validation. The agreement between the algorithms for the acceleration and angular velocity signals with the force plate was evaluated by Bland Altman analysis and linear mixed model analysis. These analyses were performed for both hoof-on and hoof-off detection and for both algorithms separately. For the hoof-on detection, the angular velocity algorithm was the most accurate with an accuracy between 2.39 and 12.22 ms and a precision of around 13.80 ms, depending on gait and hoof. For hoof-off detection, the acceleration algorithm was the most accurate with an accuracy of 3.20 ms and precision of 6.39 ms, independent of gait and hoof. These algorithms look highly promising for gait classification purposes although the applicability of these algorithms should be investigated under different circumstances, such as different surfaces and different hoof trimming conditions.


Assuntos
Algoritmos , Análise da Marcha/veterinária , Marcha/fisiologia , Cavalos/fisiologia , Aceleração , Animais , Fenômenos Biomecânicos , Feminino , Membro Anterior/fisiologia , Análise da Marcha/instrumentação , Análise da Marcha/estatística & dados numéricos , Membro Posterior/fisiologia , Casco e Garras/fisiologia , Modelos Lineares , Masculino , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/estatística & dados numéricos , Tecnologia de Sensoriamento Remoto/veterinária , Corrida/fisiologia , Caminhada/fisiologia , Tecnologia sem Fio/instrumentação , Tecnologia sem Fio/estatística & dados numéricos
7.
Neuron ; 107(4): 631-643.e5, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32516574

RESUMO

A major challenge for miniature bioelectronics is wireless power delivery deep inside the body. Electromagnetic or ultrasound waves suffer from absorption and impedance mismatches at biological interfaces. On the other hand, magnetic fields do not suffer these losses, which has led to magnetically powered bioelectronic implants based on induction or magnetothermal effects. However, these approaches have yet to produce a miniature stimulator that operates at clinically relevant high frequencies. Here, we show that an alternative wireless power method based on magnetoelectric (ME) materials enables miniature magnetically powered neural stimulators that operate up to clinically relevant frequencies in excess of 100 Hz. We demonstrate that wireless ME stimulators provide therapeutic deep brain stimulation in a freely moving rodent model for Parkinson's disease and that these devices can be miniaturized to millimeter-scale and fully implanted. These results suggest that ME materials are an excellent candidate to enable miniature bioelectronics for clinical and research applications.


Assuntos
Estimulação Encefálica Profunda/instrumentação , Neuroestimuladores Implantáveis , Tecnologia sem Fio/instrumentação , Animais , Desenho de Equipamento , Humanos
8.
PLoS One ; 15(5): e0232843, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413067

RESUMO

Pollution source parameter identification (PSPI) is significant for pollution control, since it can provide important information and save a lot of time for subsequent pollution elimination works. For solving the PSPI problem, a large number of pollution sensor nodes can be rapidly deployed to cover a large area and form a wireless sensor network (WSN). Based on the measurements of WSN, least-squares estimation methods can solve the PSPI problem by searching for the solution that minimize the sum of squared measurement noises. They are independent of the measurement noise distribution, i.e., robust to the noise distribution. To search for the least-squares solution, population-based parallel search techniques usually can overcome the premature convergence problem, which can stagnate the single-point search algorithm. In this paper, we adapt the relatively newly presented artificial bee colony (ABC) algorithm to solve the WSN-based PSPI problem and verifies its feasibility and robustness. Extensive simulation results show that the ABC and the particle swarm optimization (PSO) algorithm obtained similar identification results in the same simulation scenario. Moreover, the ABC and the PSO achieved much better performance than a traditionally used single-point search algorithm, i.e., the trust-region reflective algorithm.


Assuntos
Poluentes Atmosféricos/análise , Algoritmos , Simulação por Computador , Modelos Teóricos , Tecnologia sem Fio/instrumentação , Animais , Comportamento Apetitivo , Abelhas , Estudos de Viabilidade , Análise dos Mínimos Quadrados , Design de Software , Vento
9.
PLoS One ; 15(5): e0232460, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392253

RESUMO

In this work, a novel sensor based on printed circuit board (PCB) microstrip rectangular patch antenna is proposed to detect different ratios of ethanol alcohol in wines and isopropyl alcohol in disinfectants. The proposed sensor was designed by finite integration technique (FIT) based high-frequency electromagnetic solver (CST) and was fabricated by Proto Mat E33 machine. To implement the numerical investigations, dielectric properties of the samples were first measured by a dielectric probe kit then uploaded into the simulation program. Results showed a linear shifting in the resonant frequency of the sensor when the dielectric constant of the samples were changed due to different concentrations of ethanol alcohol and isopropyl alcohol. A good agreement was observed between the calculated and measured results, emphasizing the usability of dielectric behavior as an input sensing agent. It was concluded that the proposed sensor is viable for multipurpose chemical sensing applications.


Assuntos
Micro-Ondas , Tecnologia sem Fio/instrumentação , 2-Propanol/química , Desinfetantes/química , Radiação Eletromagnética , Engenharia , Desenho de Equipamento , Etanol/química , Vinho/análise
10.
PLoS One ; 15(5): e0232405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32357170

RESUMO

Industrial networks are currently the only communication means designed for real-time systems used in industry. Networked control systems (NCS) are still important and commonly used type of such systems operating on shop floor. As a computerized node of NCS, a programmable logic controller (PLC) is usually used. In most cases, contemporary devices of such kind are equipped with more than one network interface of various types. Typically, only one interface is activated in NCS. Sometimes, the other is used for communication between NCS and supervisory systems. Occasionally, it is additionally involved in the data transmission in the factory IT systems. In general, however, using a single network interface is a more common solution. In this paper, the mutual utilization of more than one interface is discussed in order to back up the NCS network and to manage the node-related traffic within the scope of higher level services. The question of dependability of such a system from the electromagnetic compatibility point of view is discussed. The example is provided based on Profinet via wired and wireless connection.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Automação/instrumentação , Redes de Comunicação de Computadores/instrumentação , Sistemas Computacionais , Instalação Elétrica , Fenômenos Eletromagnéticos , Indústrias/instrumentação , Tecnologia sem Fio/instrumentação
11.
PLoS One ; 15(5): e0232331, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369524

RESUMO

A floating power generation device is designed and fabricated to overcome the power supply limitations of wireless sensor networks for environmental monitoring. Once there is a temperature difference between the upper surface exposed to sunlight and the lower surface in the water, the device is capable of generating power while floating in the wetland environment. Fresnel lenses were applied to concentrate solar irradiation on a selective absorbing coat. Meanwhile two vertical axis rotors were used to cool the cold side of the thermoelectric power generator by catching the breeze. The effects of solar irradiation, temperature distribution, load resistance, wind speed, the maximum power and the electrical efficiency of the thermoelectric power generator were analyzed. When subjected to solar irradiation of 896.38 W/m2, the device generated a potential difference of 381.03 mV and a power output of 8.86 mW via thermoelectric generation. In addition, compared with the system without wind, the output power was increased by approximately 10.96% in our system. The low power wireless networks, used in wetland environments, could be operated by the thermoelectric power generated by the floating device. Besides, this system offers powering solution for self-power miniature devices that are applied in aqueous environment.


Assuntos
Fontes de Energia Elétrica , Monitoramento Ambiental/instrumentação , Energia Renovável , Áreas Alagadas , Tecnologia sem Fio/instrumentação , Desenho de Equipamento , Modelos Teóricos , Luz Solar , Temperatura , Água , Vento
12.
Science ; 368(6494): 993-1001, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32467389

RESUMO

Sophisticated devices for remote-controlled medical interventions require an electrogenetic interface that uses digital electronic input to directly program cellular behavior. We present a cofactor-free bioelectronic interface that directly links wireless-powered electrical stimulation of human cells to either synthetic promoter-driven transgene expression or rapid secretion of constitutively expressed protein therapeutics from vesicular stores. Electrogenetic control was achieved by coupling ectopic expression of the L-type voltage-gated channel CaV1.2 and the inwardly rectifying potassium channel Kir2.1 to the desired output through endogenous calcium signaling. Focusing on type 1 diabetes, we engineered electrosensitive human ß cells (Electroß cells). Wireless electrical stimulation of Electroß cells inside a custom-built bioelectronic device provided real-time control of vesicular insulin release; insulin levels peaked within 10 minutes. When subcutaneously implanted, this electrotriggered vesicular release system restored normoglycemia in type 1 diabetic mice.


Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Estimulação Elétrica/instrumentação , Secreção de Insulina/genética , Células Secretoras de Insulina/metabolismo , Tecnologia sem Fio/instrumentação , Animais , Biônica , Canais de Cálcio Tipo L/genética , Sinalização do Cálcio , Engenharia Celular , Células HEK293 , Humanos , Masculino , Camundongos , Canais de Potássio Corretores do Fluxo de Internalização/genética , Próteses e Implantes , Transcrição Genética , Transgenes
13.
Phys Med Biol ; 65(11): 11NT02, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32311679

RESUMO

This work aims to characterize the novel DRX Plus 3543C detector in terms of detective quantum efficiency (DQE) using both a mobile x-ray system called Carestream DRX Revolution Nano and a traditional x-ray system (Carestream DRX Evolution). We used the commercial system DRX Revolution Nano, equipped with a new x-ray source based on CNT technology and field emission (FE) as the electron emitter (cathode). An innovative aspect of this device is its intrinsic selection of the focal spot size. We tested the system using three IEC-specified beam qualities (RQA3, 5 and 7) in terms of modulation transfer function (MTF), normalized noise power spectra (NNPS) and DQE as defined in the IEC 62220-1-1:2015. We compared the results obtained using DRX Revolution Nano and DRX Evolution with correlation and with Bland-Altman plots to study their agreement. RQA3 MTF is slightly lower than the RQA5 and 7 curves between 0.5 and 2.5 cycles mm-1. We measured MTF values of about 0.6 at 1 lp mm-1 and about 0.28 lp mm-1 at 2 lp mm-1. The NNPS curves show a decreasing trend with the energy regarding the DRX Revolution Nano. On the other hand, the DRX Evolution NNPS curve at RQA3 is greater than the one at RQA5, but the one at RQA5 is less than the one at RQA7. The DQE(0) ranged between about 0.82 (DRX Evolution at RQA3) and 0.54 (DRX Evolution at RQA7). As expected, the squared Pearson's correlation coefficients between the two x-ray tubes were always in an optimal agreement, and Bland-Altman plots confirmed a substantial equivalence between the two physical characterizations of the wireless detector. In conclusion, we can show that the dynamic focal selection of the system equipped with CNT does not play a substantial role in image quality compared to a traditional system in terms of physical characterisation of the detector in our measurement conditions.


Assuntos
Nanotubos de Carbono/química , Dosímetros de Radiação/normas , Radiografia/métodos , Radiografia/instrumentação , Tecnologia sem Fio/instrumentação , Raios X
14.
Nanotechnology ; 31(25): 252001, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32101794

RESUMO

In in vivo postsurgery monitoring, the use of wireless biodegradable implantable sensors has gained and is gaining a lot of interest, particularly in cases of monitoring for a short period of time. The employment of biodegradable materials allows the circumvention of secondary surgery for device removal. Additionally, the use of wireless communication for data elaboration avoids the need for transcutaneous wires. As such, it is possible to prevent possible inflammation and infections associated with long-term implants which are not wireless. It is expected that microfabricated biodegradable sensors will have a strong impact in acute or transient biomedical applications. However, the design of such high-performing electronic systems, both fully biodegradable and wireless, is very complex, particularly at small scales. The associated technologies are still in their infancy and should be more deeply and extensively investigated in animal models and, successively, in humans, before being clinically implemented. In this context, the present review aims to provide a complete overview of wireless biodegradable implantable sensors, covering the vital signs to be monitored, the wireless technologies involved, and the biodegradable materials used for the production of the devices, as well as designed devices and their applications. In particular, both their advantages and drawbacks are highlighted, and the key challenges faced, mainly associated with fabrication techniques, and control over degradation kinetics and biocompatibility of the device, are reported and discussed.


Assuntos
Monitorização Fisiológica/instrumentação , Cuidados Pós-Operatórios/instrumentação , Implantes Absorvíveis , Desenho de Equipamento , Humanos , Microtecnologia/instrumentação , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação
15.
Sensors (Basel) ; 20(3)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028736

RESUMO

The growing need for food worldwide requires the development of a high-performance, high-productivity, and sustainable agriculture, which implies the introduction of new technologies into monitoring activities related to control and decision-making. In this regard, this paper presents a hierarchical structure based on the collaboration between unmanned aerial vehicles (UAVs) and federated wireless sensor networks (WSNs) for crop monitoring in precision agriculture. The integration of UAVs with intelligent, ground WSNs, and IoT proved to be a robust and efficient solution for data collection, control, analysis, and decisions in such specialized applications. Key advantages lay in online data collection and relaying to a central monitoring point, while effectively managing network load and latency through optimized UAV trajectories and in situ data processing. Two important aspects of the collaboration were considered: designing the UAV trajectories for efficient data collection and implementing effective data processing algorithms (consensus and symbolic aggregate approximation) at the network level for the transmission of the relevant data. The experiments were carried out at a Romanian research institute where different crops and methods are developed. The results demonstrate that the collaborative UAV-WSN-IoT approach increases the performances in both precision agriculture and ecological agriculture.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Tecnologia sem Fio/instrumentação , Produtos Agrícolas , Coleta de Dados , Humanos , Tecnologia de Sensoriamento Remoto
16.
Sci Rep ; 10(1): 2067, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034237

RESUMO

About 30% of patients with impaired cardiac function have ventricular dyssynchrony and seek cardiac resynchronization therapy (CRT). In this study, we demonstrate synchronized biventricular (BiV) pacing in a leadless fashion by implementing miniaturized and wirelessly powered pacemakers. With their flexible form factors, two pacemakers were implanted epicardially on the right and left ventricles of a porcine model and were inductively powered at 13.56 MHz and 40.68 MHz industrial, scientific, and medical (ISM) bands, respectively. The power consumption of these pacemakers is reduced to µW-level by a novel integrated circuit design, which considerably extends the maximum operating distance. Leadless BiV pacing is demonstrated for the first time in both open-chest and closed-chest porcine settings. The clinical outcomes associated with different interventricular delays are verified through electrophysiologic and hemodynamic responses. The closed-chest pacing only requires the external source power of 0.3 W and 0.8 W at 13.56 MHz and 40.68 MHz, respectively, which leads to specific absorption rates (SARs) 2-3 orders of magnitude lower than the safety regulation limit. This work serves as a basis for future wirelessly powered leadless pacemakers that address various cardiac resynchronization challenges.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Tecnologia sem Fio , Animais , Desfibriladores Implantáveis , Modelos Animais de Doenças , Fontes de Energia Elétrica , Eletrocardiografia , Desenho de Equipamento , Feminino , Suínos , Tecnologia sem Fio/instrumentação
17.
Talanta ; 211: 120757, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070607

RESUMO

Driving under the influence of cannabis and alcohol represents a major safety concern due to the synergistic or additive effect of these substances of abuse. Hence, rapid road-site testing of these substances is highly desired to reduce risks of fatal accidents. Here we describe a wearable electrochemical sensing device for the simultaneous direct, decentralized, detection of salivary THC and alcohol. The new ring-based sensing platform contains a voltammetric THC sensor and an amperometric alcohol biosensor on the ring cap, along with the wireless electronics embedded within the ring case. Rapid replacement of the disposable sensing-electrode ring cap following each saliva assay is accomplished by aligning spring-loaded pins, mounted on the electronic board (PCB), with the current collectors of the sensing electrodes. The printed dual-analyte sensor ring cover is based on a MWCNT/carbon electrode for the THC detection along with a Prussian-blue transducer, coated with alcohol oxidase/chitosan reagent layer, for the biosensing of alcohol. THC and alcohol can thus be detected simultaneously in the same diluted saliva sample within 3 min, with no cross talk and no interferences from the saliva matrix. The new wearable ring sensor platform should enable law enforcement personnel to screen drivers in a single traffic stop and offers considerable promise for addressing growing concerns of drug-impaired driving.


Assuntos
Técnicas Biossensoriais/métodos , Dronabinol/análise , Eletroquímica , Etanol/análise , Saliva/metabolismo , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação , Depressores do Sistema Nervoso Central/análise , Eletrodos , Dedos , Humanos , Psicotrópicos/análise , Saliva/química , Detecção do Abuso de Substâncias/métodos
18.
Sensors (Basel) ; 20(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979184

RESUMO

In this paper we proposed a wearable electrocardiogram (ECG) telemonitoring system for atrial fibrillation (AF) detection based on a smartphone and cloud computing. A wearable ECG patch was designed to collect ECG signals and send the signals to an Android smartphone via Bluetooth. An Android APP was developed to display the ECG waveforms in real time and transmit every 30 s ECG data to a remote cloud server. A machine learning (CatBoost)-based ECG classification method was proposed to detect AF in the cloud server. In case of detected AF, the cloud server pushed the ECG data and classification results to the web browser of a doctor. Finally, the Android APP displayed the doctor's diagnosis for the ECG signals. Experimental results showed the proposed CatBoost classifier trained with 17 selected features achieved an overall F1 score of 0.92 on the test set (n = 7,270). The proposed wearable ECG monitoring system may potentially be useful for long-term ECG telemonitoring for AF detection.


Assuntos
Fibrilação Atrial/diagnóstico , Eletrocardiografia Ambulatorial/instrumentação , Eletrocardiografia Ambulatorial/métodos , Eletrocardiografia/instrumentação , Eletrocardiografia/métodos , Algoritmos , Computação em Nuvem , Humanos , Aprendizado de Máquina , Processamento de Sinais Assistido por Computador/instrumentação , Smartphone , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação
19.
Proc Natl Acad Sci U S A ; 117(6): 2835-2845, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31974306

RESUMO

Recording cell-specific neuronal activity while monitoring behaviors of freely moving subjects can provide some of the most significant insights into brain function. Current means for monitoring calcium dynamics in genetically targeted populations of neurons rely on delivery of light and recording of fluorescent signals through optical fibers that can reduce subject mobility, induce motion artifacts, and limit experimental paradigms to isolated subjects in open, two-dimensional (2D) spaces. Wireless alternatives eliminate constraints associated with optical fibers, but their use of head stages with batteries adds bulk and weight that can affect behaviors, with limited operational lifetimes. The systems introduced here avoid drawbacks of both types of technologies, by combining highly miniaturized electronics and energy harvesters with injectable photometric modules in a class of fully wireless, battery-free photometer that is fully implantable subdermally to allow for the interrogation of neural dynamics in freely behaving subjects, without limitations set by fiber optic tethers or operational lifetimes constrained by traditional power supplies. The unique capabilities of these systems, their compatibility with magnetic resonant imaging and computed tomography and the ability to manufacture them with techniques in widespread use for consumer electronics, suggest a potential for broad adoption in neuroscience research.


Assuntos
Encéfalo/fisiologia , Fotometria/métodos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Desenho de Equipamento , Imagem por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Fotometria/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação
20.
J Med Eng Technol ; 44(1): 12-19, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31939688

RESUMO

With the current advancement in technology, the use of Wireless Body Area Networks (WBANs) has become popular in the healthcare management. They provide a mechanism to collect and transmit physiological data to healthcare providers in remote locations. With the need to secure healthcare data becoming a global concern, mechanisms must be put in place to ensure secure communication of physiological data collected in WBANs. This paper, presents a new authentication scheme for WBANs based on Elliptic Curve Cryptography. Sensor nodes used in WBANs are resource constraint and for that reason, the proposed scheme is both certificateless and pairing-free. We compared the efficiency of our proposed authentication scheme with other related schemes and found that our scheme had considerable efficiency in terms of communication cost and running time.


Assuntos
Tecnologia sem Fio/instrumentação , Algoritmos , Serviços de Saúde Comunitária/métodos , Confidencialidade , Humanos
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