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1.
Sensors (Basel) ; 22(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35891131

RESUMEN

In this work, a two-dimensional (2D) position-detection device using a single axis magnetic sensor combined with orthogonal gradient coils was designed and fabricated. The sensors used were an induction coil and a GMR spin-valve sensor GF807 from Sensitec Inc. The field profiles generated by the two orthogonal gradient coils were analyzed numerically to achieve the maximum linear range, which corresponded to the detection area of the tracking system. The two coils were driven by 1-kHz sine wave currents with a 90° phase difference to generate the fields with uniform gradients along the x- and y-axis in the plane of the tracking stage. The gradient fields were detected by a single-axis sensor incorporated with a digital dual-phase lock-in detector to retrieve the position information. A linearity correction algorithm was used to improve the location accuracy and to extend the linear range for position sensing. The mean positioning error was found to be 0.417 mm, corresponding to the relative error of 0.21% in the working range of 200 mm × 200 mm, indicating that the proposed tracking system is promising for applications requiring accurate control of the two-dimensional position.

2.
Sensors (Basel) ; 22(20)2022 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-36298205

RESUMEN

Convolutional neural networks (CNNs) play a key role in deep learning applications. However, the high computational complexity and high-energy consumption of CNNs trammel their application in hardware accelerators. Computing-in-memory (CIM) is the technique of running calculations entirely in memory (in our design, we use SRAM). CIM architecture has demonstrated great potential to effectively compute large-scale matrix-vector multiplication. CIM-based architecture for event detection is designed to trigger the next stage of precision inference. To implement an SRAM-based CIM accelerator, a software and hardware co-design approach must consider the CIM macro's hardware limitations to map the weight onto the AI edge devices. In this paper, we designed a hierarchical AI architecture to optimize the end-to-end system power in the AIoT application. In the experiment, the CIM-aware algorithm with 4-bit activation and 8-bit weight is examined on hand gesture and CIFAR-10 datasets, and determined to have 99.70% and 70.58% accuracy, respectively. A profiling tool to analyze the proposed design is also developed to measure how efficient our architecture design is. The proposed design system utilizes the operating frequency of 100 MHz, hand gesture and CIFAR-10 as the datasets, and nine CNNs and one FC layer as its network, resulting in a frame rate of 662 FPS, 37.6% processing unit utilization, and a power consumption of 0.853 mW.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Programas Informáticos , Gestos , Diseño de Equipo
3.
Sensors (Basel) ; 21(4)2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33562587

RESUMEN

The optical characteristics of copper ion detection, such as the photometric absorbance of specific wavelengths, exhibit significant intensity change upon incident light into the aqueous solutions with different concentrations of metal ions due to the electron transition in the orbit. In this study, we developed a low-cost, small-size and fast-response photoelectric sensing prototype as an optic sensor for copper (Cu) ions detection by utilizing the principle of optical absorption. We quantified the change of optical absorbance from infra-red (IR) light emitting diodes (LEDs) upon different concentrations of copper ions and the transmitted optical signals were transferred to the corresponding output voltage through a phototransistor and circuit integrated in the photoelectric sensing system. The optic sensor for copper (Cu) ions demonstrated not only excellent specificity with other metal ions such as cadmium (Cd), nickel (Ni), iron (Fe) and chloride (Cl) ions in the same aqueous solution but also satisfactory linearity and reproducibility. The sensitivity of the preliminary sensing system for copper ions was 29 mV/ppm from 0 to 1000 ppm. In addition, significant ion-selective characteristics and anti-interference capability were also observed in the experiments by the proposed approach.

4.
J Surg Oncol ; 120(7): 1162-1168, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31556139

RESUMEN

BACKGROUND: Vascularized lymph node transfer (VLNT) is an effective surgery for extremity lymphedema. This study evaluated a lymphatic drainage device (LDD) for the drainage of accumulated fluid into the venous system. METHODS: Micropore filtering membranes with pore sizes of 5, 0.65, and 0.22 µm polyvinylidene difluoride, and 0.8 µm Nylon Net Filter were evaluated to determine the in vitro efficiency of drainage flow of an LDD. The two superior membranes were further used for the evaluation of the inflow and outflow of the LDD in vivo using 5% albumin. RESULTS: At 5 minutes, the volumes drained with 5, 0.65, and 0.22 µm polyvinylidene difluoride and 0.8 µm nylon membranes were 15.2, 2.77, 2.37, and 0.59 mL, respectively (P < .01). At 10 minutes, the collected volumes of 5 and 0.65 µm polyvinylidene difluoride were 1788 and 1051 µL (P = .3). The indocyanine green fluorescence was detected at 50 seconds for the 5 µm polyvinylidene difluoride membrane but not for the 0.65 µm membrane. CONCLUSIONS: The study successfully demonstrated the proof-of-concept of the LDD prototype that mimicked VLNT with drainage of 5% albumin into the venous system in a rat model.


Asunto(s)
Modelos Animales de Enfermedad , Drenaje/instrumentación , Drenaje/métodos , Linfedema/terapia , Animales , Diseño de Equipo , Verde de Indocianina/metabolismo , Bombas de Infusión Implantables , Masculino , Ratas , Ratas Sprague-Dawley , Recuperación de la Función
5.
Sensors (Basel) ; 19(8)2019 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-31010005

RESUMEN

A non-contact current measurement device comprised of a GMR sensor and a ferrite ring core was investigated. The sensor chip employed a high-sensitivity spin-valve full-bridge GMR sensor of which the direct output has non-negligible hysteresis and a limited linear range. By applying an AC modulation current to modulate the output of the GMR sensor, the hysteresis was reduced, and the linear range was over ±0.5 A. The resolution for DC and quasi-static current measurement was 0.1 mA at a 10 Hz bandwidth. The output in proportion to the measured current was obtained either by demodulating the current-sensitive AC signal or by employing the filtered output of the intrinsically nonlinear spin-valve response. The proposed current sensing scheme is suitable for quasi-static current measurement from DC to over 100 Hz.

6.
BMC Microbiol ; 16(1): 175, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27484120

RESUMEN

BACKGROUND: Streptococcus agalactiae (GBS) is a common pathogen to infect newborn, woman, the elderly, and immuno-compromised human and fish. 37 fish isolates and 554 human isolates of the GBS in 2007-2012 were investigated in serotypes, antibiotic susceptibility, genetic difference and pathogenicity to tilapia. RESULTS: PCR serotyping determined serotype Ia for all fish GBS isolates and only in 3.2 % (3-4.2 %) human isolates. For fish isolates, all consisted a plasmid less than 6 kb and belonged to ST7 type, which includes mainly pulsotypes I and Ia, with a difference in a deletion at the largest DNA fragment. These fish isolates were susceptible to all antimicrobials tested in 2007 and increased in non-susceptibility to penicillin, and resistance to clindamycin and ceftriaxone in 2011. Differing in pulsotype and lacking plasmid from fish isolates, human serotype Ia isolates were separated into eight pulsotypes II-IX. Main clone ST23 included pulsotypes II and IIa (50 %) and ST483 consisted of pulsotype III. Human serotype Ia isolates were all susceptible to ceftriaxone and penicillin and few were resistant to erythromycin, azithromycin, clindamycin, levofloxacin and moxifloxacine with the resistant rate of 20 % or less. Using tilapia to analyze the pathogenesis, fish isolates could cause more severe symptoms, including hemorrhage of the pectoral fin, hemorrhage of the gill, and viscous black and common scites, and mortality (>95 % for pulsotype I) than the human isolates (<30 %); however, the fish pulostype Ia isolate 912 with deletion caused less symptoms and the lowest mortality (<50 %) than pulsotype I isolates. CONCLUSION: Genetic, pathogenic, and antimicrobial differences demonstrate diverse origin of human and fish serotype Ia isolates. The pulsotype Ia of fish serotype Ia isolates may be used as vaccine strains to prevent the GBS infection in fish.


Asunto(s)
Enfermedades de los Peces/microbiología , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/genética , Animales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/aislamiento & purificación , Taiwán
7.
Sensors (Basel) ; 15(6): 14727-44, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26102496

RESUMEN

A new class of tri-axial miniature magnetometer consisting of a planar fluxgate structure with an orthogonal ferromagnetic fluxguide centrally situated over the magnetic cores is presented. The magnetic sensor possesses a cruciform ferromagnetic core placed diagonally upon the square excitation coil under which two pairs of pick-up coils for in-plane field detection are allocated. Effective principles and analysis of the magnetometer for 3-D field vectors are described and verified by numerically electromagnetic simulation for the excitation and magnetization of the ferromagnetic cores. The sensor is operated by applying the second-harmonic detection technique that can verify V-B relationship and device responsivity. Experimental characterization of the miniature fluxgate device demonstrates satisfactory spatial magnetic field detection results in terms of responsivity and noise spectrum. As a result, at an excitation frequency of 50 kHz, a maximum in-plane responsivity of 122.4 V/T appears and a maximum out-of-plane responsivity of 11.6 V/T is obtained as well. The minimum field noise spectra are found to be 0.11 nT/√Hz and 6.29 nT/√Hz, respectively, in X- and Z-axis at 1 Hz under the same excitation frequency. Compared with the previous tri-axis fluxgate devices, this planar magnetic sensor with an orthogonal fluxguide provides beneficial enhancement in both sensory functionality and manufacturing simplicity. More importantly, this novel device concept is considered highly suitable for the extension to a silicon sensor made by the current CMOS-MEMS technologies, thus emphasizing its emerging applications of field detection in portable industrial electronics.

8.
Sensors (Basel) ; 15(10): 24961-76, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26404283

RESUMEN

A miniature intra-oral dental implant system including a built-in biosensor device is proposed in this article. The dental implant system, or platform, is replaced over maxilla and allows relatively non-invasive procedures for a novel biosensing scheme for human blood analysis. Due to placement of the implant fixture, periodontal ligaments and the pulp structure, which are regarded as the main origin of pain, are thus removed, and long-term, continuous blood analysis and management through maxillary bone marrow becomes achievable through the dental implant platform. The new pathway of biological sensing is for the first time presented to realize an accurate and painless approach without injections. The dental implant system mainly consists of an implant fixture and a prosthetic abutment, a biosensor module, a bluetooth 4.0 wireless module and a dc button cell battery. The electrochemical biosensor possesses three electrodes, including working, reference and counter ones, which are arranged to pass through the titanium implant fixture below the biosensor module. The electrodes are exposed to the blood pool inside the maxillary bone marrow and perform oxidation/reduction reactions with the coating of biosensing enzyme. To prove the proposed platform, the immobilization process of glucose oxidase (GOD) enzyme and in vitro detections of glucose levels are successfully carried out, and proven sensitivity, linearity and repeatability of the glucose biosensor system are obtained. Moreover, a preliminary canine animal model adopting the new pathway shows significant consistency with the traditional method through dermal pricks for blood sugar detection. Despite the prospective results, further challenges in engineering implementation and clinical practices are addressed and discussed. In brief, the novel biosensing pathway and intra-oral biosensor platform may increasingly reveal their promising value and feasibilities in current bio-medical analysis, diagnosis, drug release and even healthcare technologies.


Asunto(s)
Técnicas Biosensibles/instrumentación , Glucemia/análisis , Implantes Dentales , Diabetes Mellitus/sangre , Animales , Automonitorización de la Glucosa Sanguínea/instrumentación , Automonitorización de la Glucosa Sanguínea/métodos , Pilares Dentales , Perros , Electrodos , Enzimas Inmovilizadas/metabolismo , Estudios de Factibilidad , Glucosa Oxidasa/metabolismo , Humanos
9.
Sensors (Basel) ; 14(8): 13815-29, 2014 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-25196107

RESUMEN

This paper presents a novel class of miniature fluxgate magnetometers fabricated on a print circuit board (PCB) substrate and electrically connected to each other similar to the current "flip chip" concept in semiconductor package. This sensor is soldered together by reversely flipping a 5 cm × 3 cm PCB substrate to the other identical one which includes dual magnetic cores, planar pick-up coils, and 3-D excitation coils constructed by planar Cu interconnections patterned on PCB substrates. Principles and analysis of the fluxgate sensor are introduced first, and followed by FEA electromagnetic modeling and simulation for the proposed sensor. Comprehensive characteristic experiments of the miniature fluxgate device exhibit favorable results in terms of sensitivity (or "responsivity" for magnetometers) and field noise spectrum. The sensor is driven and characterized by employing the improved second-harmonic detection technique that enables linear V-B correlation and responsivity verification. In addition, the double magnitude of responsivity measured under very low frequency (1 Hz) magnetic fields is experimentally demonstrated. As a result, the maximum responsivity of 593 V/T occurs at 50 kHz of excitation frequency with the second harmonic wave of excitation; however, the minimum magnetic field noise is found to be 0.05 nT/Hz(1/2) at 1 Hz under the same excitation. In comparison with other miniature planar fluxgates published to date, the fluxgate magnetic sensor with flip chip configuration offers advances in both device functionality and fabrication simplicity. More importantly, the novel design can be further extended to a silicon-based micro-fluxgate chip manufactured by emerging CMOS-MEMS technologies, thus enriching its potential range of applications in modern engineering and the consumer electronics market.


Asunto(s)
Electrónica/instrumentación , Diseño de Equipo/instrumentación , Magnetismo/instrumentación , Electricidad , Fenómenos Electromagnéticos , Campos Magnéticos , Ruido
10.
ScientificWorldJournal ; 2012: 941685, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22645476

RESUMEN

This paper shows a new finding about the decrease of relaxative response to loperamide in prostate of spontaneously hypertensive rats (SHR) as compare to normal rats (WKY). Authors demonstrated the reduction of ATP-sensitive potassium channels is responsible for this change using immunoblotting analysis and the decrease of action induced by diazoxide. This view is not mentioned before and is the first one reporting this result.


Asunto(s)
Loperamida/farmacología , Próstata/efectos de los fármacos , Adenosina Trifosfato/química , Animales , Antidiarreicos/farmacología , Diazóxido/química , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Canales KATP/química , Masculino , Canales de Potasio/química , Canales de Potasio de Rectificación Interna/química , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Receptores Opioides/metabolismo , Receptores Opioides mu/química , Temperatura
11.
Comput Methods Programs Biomed ; 219: 106762, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35378394

RESUMEN

BACKGROUND AND OBJECTIVE: The automatic recognition of myocardial infarction (MI) by artificial intelligence (AI) has been an emerging topic of academic research and an existing classification method that can recognize conventional electrocardiogram (ECG) signals with high accuracy. However, they are employed to classify one-dimensional (1-D) ECG signals rather than three-dimensional (3-D) ECG images, and it is limited to provide physicians with significant recommendations to aid in diagnosis like highlighting abnormal leads. Other studies on 3-D ECG images either did not achieve high accuracy or did not employ an inter-patient classification scheme. By proposing a multi-VGG deep neural network, this study aims to develop an automatic classification method for identifying myocardial infarction with inter-patient high accuracy and proper interpretability using 3-D ECG image and a Grad-CAM++ method. METHODS: We apply a multi-VGG deep convolutional neural network to top-view images of 3-D ECG, which are generated from simply denoised standard 12 leads ECG signals for classification. The multi-network method, which separately classifies QRS areas, ST areas, and whole heartbeats, was applied to improve classification performance. Furthermore, the Grad-CAM++ method was used to provide visually interpretable heatmaps for user's attention to improve network interpretability and assist physicians in MI diagnosis RESULTS: The proposed method achieved 95.65% inter-patient accuracy and exactly perfect inner-patient accuracy in the Physikalisch-Technische Bundesanstalt (PTB) diagnostic ECG database experiment. In the PTB-XL diagnostic ECG database, the proposed method achieved 97.23% inter-patient accuracy. The Grad-CAM++ experiment results also showed that the highlighted areas matched the medical diagnosis criteria for myocardial infarction. CONCLUSIONS: Our method demonstrates that 3-D ECG images with AI classification can be efficiently employed for heart disease diagnosis with both high accuracy and visual interpretability.


Asunto(s)
Inteligencia Artificial , Infarto del Miocardio , Algoritmos , Bases de Datos Factuales , Electrocardiografía/métodos , Humanos , Infarto del Miocardio/diagnóstico , Redes Neurales de la Computación
12.
Sensors (Basel) ; 10(1): 670-83, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-22315561

RESUMEN

An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO(2) nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO(2) chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors.


Asunto(s)
Óxido de Aluminio/química , Galvanoplastia/instrumentación , Oximetría/instrumentación , Oxígeno/análisis , Titanio/química , Transductores , Electrodos , Diseño de Equipo , Análisis de Falla de Equipo , Porosidad
13.
Medicine (Baltimore) ; 99(47): e23083, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33217809

RESUMEN

In the present study, we retrospectively analyzed the records of surgical confirmed kidney cancer with renal cell carcinoma pathology in the database of the hospital. We evaluated the significance of cancer size by assessing the outcomes of proposed adaptive active contour model (ACM). The aim of our study was to develop an adaptive ACM method to measure the radiological size of kidney cancer on computed tomography in the hospital patients. This paper proposed a set of medical image processing, applying images provided by the hospital and select the more obvious cases by the doctors, after the first treatment to remove noise image, and the kidney cancer contour would be circled by using the proposed adaptive ACM method. The results showed that the experimental outcome has highly similarity with the medical professional manual contour. The accuracy rate is higher than 99%. We have developed a novel adaptive ACM approach that well combines a knowledge-based system to contour the kidney cancer size in computed tomography imaging to support the clinical decision.


Asunto(s)
Neoplasias Renales/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Medios de Contraste , Femenino , Humanos , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Mejoramiento de la Calidad , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
Sex Med ; 7(4): 451-458, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31540883

RESUMEN

INTRODUCTION: The comorbidity between premature ejaculation (PE) and erectile dysfunction (ED) has not yet been clarified. AIM: To assess the comorbidity between PE and ED. METHODS: Male members of a shopping club in Taiwan aged 20-60 years with stable sexual relationships were invited to complete an online questionnaire. MAIN OUTCOME MEASURES: Self-estimated intravaginal ejaculatory latency time (IELT), Premature Ejaculation Diagnostic Tool, Sexual Health Inventory for Men, Self-Esteem and Relationship, and Hospital Anxiety and Depression Scale results were used. RESULTS: A total of 937 participants with a mean age of 41.1 ± 10.2 years were enrolled. The prevalence rates of ED (Sexual Health Inventory for Men ≤ 21), PE (Premature Ejaculation Diagnostic Tool ≥11), and IELT ≤1 minute were 24.7%, 6.3%, and 6.4%, respectively. Prevalence of acquired PE and IELT ≤1 minute increased marginally with age. Participants with ED had a greater prevalence of PE than those without ED (19.5% vs 2.0%, P < .001), and participants with PE had a greater prevalence of ED than those without PE (76.3% vs 19.4%, P < .001). Compared with participants without PE, participants with PE had greater adjusted odds of ED (odds ratio [OR] = 12.7, 95% CI = 6.7-24.2). Relative to participants without ED, participants with ED had increased adjusted odds of PE (OR = 7.2, 95% CI = 3.5-14.6 with mild ED and OR = 36.7, 95% CI = 16.2-83.0 with ED severity greater than a mild degree). Poor sexual relationships and self-esteem, depression, and anxiety were reported more frequently in those with PE or ED, especially in those with both problems compared with those without PE and ED. CONCLUSIONS: This study confirmed a high prevalence of PE and ED coexistence, indicating a complicated relationship between the 2 conditions and the importance of screening for their co-occurrence in practice. Tsai W-K, Chiang P-K, Lu C-C, et al. The Comorbidity Between Premature Ejaculation and Erectile Dysfunction-A Cross-Sectional Internet Survey. Sex Med 2019;7:451-458.

15.
PLoS One ; 13(7): e0199620, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29965977

RESUMEN

Self-organized dendritic architecture is of fundamental importance and its application can be used in many natural and industrial processes. Nanopost arrays are usually used in the applications of reflecting grating and changing the material surface wettability. However, in recent research, it is found that nanopost arrays can be fabricated as passive components to induce the dendritic self-organizaed hierarchical architectures. Via this simplified Phase-Field based finite element simulation, the surface dendritic self-organized architecture morphology and expanding speed in the growing path can be controlled by nanopost structures. In addition, nanopost array arrangement on the surface affects the hierarchal architecture branching distribution. Finally, with an external applied force introduced to the system, it enables the nanopost as an active component. It is found that nanopost surroundings significantly impact the final distribution of dendritic architectures which is qualitatively in agreement with experiments and induce these dendritic architectures to form assigned character patterns after the external driving forces are introduced into the system. This novel study can fundamentally study the dynamic physics of dendritic self-organized architecutes provide an indicator for the development of smart self-organized architecture, and a great opportunity for the creation of large-scale hierarchical structures.


Asunto(s)
Simulación por Computador , Modelos Teóricos , Algoritmos
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