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1.
IEEE Trans Biomed Circuits Syst ; 16(4): 600-608, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35536796

RESUMEN

In modern medicine, smart wireless connected devices are gaining an increasingly important role in aiding doctors' job of monitoring patients. More and more complex systems, with a high density of sensors capable of monitoring many biological signals, are arising. Merging the data offers a great opportunity for increasing the reliability of diagnosis. However, a huge problem is constituted by synchronization. Multi-board wireless-connected monitoring systems are a typical example of distributed systems and synchronization has always been a challenging issue. In this paper, we present a distributed full synchronized system for monitoring patients' health capable of heartbeat rate, oxygen saturation, gait and posture analysis, and muscle activity measurements. The time synchronization is guaranteed thanks to the Fractional Low-power Synchronization Algorithm (FLSA).


Asunto(s)
Redes de Comunicación de Computadores , Salud Global , Marcha/fisiología , Humanos , Monitoreo Fisiológico , Reproducibilidad de los Resultados
2.
Sensors (Basel) ; 22(4)2022 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-35214333

RESUMEN

Radio localization and radio positioning are relevant research fields for many telecommunications technologies. Usually, the solutions proposed by the literature rely on adaptive techniques related to some parameters that can be extracted from the received signal in cooperative device tracking. In this paper, we explore the artifacts that may be introduced into Angle-of-Arrival estimation based on phase interferometry, and we introduce a simple technique to mitigate their impact. Details of the mathematical discussion are presented and the approach is experimentally validated. The experimental results are compared with raw data to demonstrate the effectiveness of the proposed technique.

3.
Sensors (Basel) ; 21(13)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202173

RESUMEN

A potential rise in interest in the Internet of Things in the upcoming years is expected in the fields of healthcare, supply chain, logistics, industries, smart cities, smart homes, cyber physical systems, etc. This paper discloses the fusion of the Internet of Things (IoT) with the so-called "distributed ledger technology" (DLT). IoT sensors like temperature sensors, motion sensors, GPS or connected devices convey the activity of the environment. Sensor information acquired by such IoT devices are then stored in a blockchain. Data on a blockchain remains immutable however its scalability still remains a challenging issue and thus represents a hindrance for its mass adoption in the IoT. Here a communication system based on IOTA and DLT is discussed with a systematic architecture for IoT devices and a future machine-to-machine (M2M) economy. The data communication between IoT devices is analyzed using multiple use cases such as sending DHT-11 sensor data to the IOTA tangle. The value communication is analyzed using a novel "micro-payment enabled over the top" (MP-OTT) streaming platform that is based on the "pay-as-you-go" and "consumption based" models to showcase IOTA value transactions. In this paper, we propose an enhancement to the classical "masked authenticated message" (MAM) communication protocol and two architectures called dual signature masked authenticated message (DSMAM) and index-based address value transaction (IBAVT). Further, we provided an empirical analysis and discussion of the proposed techniques. The implemented solution provides better address management with secured sharing and communication of IoT data, complete access control over the ownership of data and high scalability in terms of number of transactions that can be handled.

4.
Anal Bioanal Chem ; 407(16): 4513-22, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25814272

RESUMEN

In this study, we demonstrate the application of ambient mass spectrometry for measuring fatty acids from various biological sample matrices such as olive oil, fish oil, salmon, and human serum. Optimum performance was obtained after spotting samples onto thin-layer chromatography (TLC) plates as sample substrates for a custom-built solvent-assisted desorption/ionization mass spectrometry (DI-MS) interface. Good to excellent linearities (coefficients of determination, 0.9856 to 0.9977) and reproducibilities (average 6 % relative standard deviation (RSD) using syringe deposition) were obtained after application of an internal standard. Signal suppression phenomena were minimized by separating the analytes by TLC to some extent prior to DI-MS, leading to a fourfold increase of signal-to-noise ratios as compared to single spot mixture analysis without TLC separation. Graphical Abstract Solvent-assisted desorption/ionization-mass spectrometry.


Asunto(s)
Cromatografía en Capa Delgada/métodos , Ácidos Grasos/análisis , Espectrometría de Masas/métodos , Animales , Humanos , Reproducibilidad de los Resultados , Salmón
5.
Anticancer Res ; 34(9): 4775-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25202057

RESUMEN

BACKGROUND/AIM: The study of fatty acid composition of the erythrocytes' membrane can be considered an appropriate biomarker for investigating the relations of the pattern of fatty acids metabolism to a specific disease. The aim of the present study was to analyze the fatty acid profile in red blood cell membranes of patients with colorectal cancer (CRC). MATERIALS AND METHODS: Thirteen patients with CRC and 13 patients with no malignant disease were enrolled in the study. Fatty acids were extracted from erythrocytes' membranes and quantified by gas chromatography. The data were analyzed using the Mann-Whitney test. RESULTS: Patients with CRC showed significantly lower mean percentage of n-3 polynunsatured fatty acids (n-3 PUFAs) than controls (5.1% vs. 8.0%, respectively). This finding was reflected in the higher ratio n-6-PUFA/n-3-PUFA observed in cancer patients. CONCLUSION: Lipidomic analysis of erythrocyte membranes confirmed the presence of an altered fatty acid profile in patients with CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Membrana Eritrocítica/metabolismo , Ácidos Grasos/metabolismo , Anciano , Estudios de Casos y Controles , Neoplasias Colorrectales/patología , Ácidos Grasos/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias
6.
Clin Exp Rheumatol ; 31(3): 389-93, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23406833

RESUMEN

OBJECTIVES: We aimed to measure the fractal dimension on x-ray images and ultrasonographic parameters of the os calcis of bone from 4 districts in osteoporotic patients and in control subjects, in order to test the hypothesis that ultrasonographic parameters correlate to the fractal dimension obtained on x-ray images. METHODS: Fractal analysis on radiological images from 4 bone districts (proximal femur, calcaneus, metacarpus and 3rd phalanx) was performed in a study comparing ultrasonographic evaluation of the os calcis in severe osteoporotic patients and in control cases. We studied 86 x-ray-views from patients with severe reduction of ultrasound Stiffness Index and in healthy women. Ultrasound measurements of left os calcis were performed using the Lunar Achilles-Plus instrument. Fractal analysis was performed using the box-counting method. RESULTS: In healthy subjects, fractal dimension, D, measure of structural complexity, resulted close to the topological dimension (no fractal structure), TD, in femur (1.99±0.03)and phalanx (1.96±0.03), D differed significantly from TD in calcaneus (D=1.90±0.02; p<0.001) and metacarpus (D=1.89±0.03, p<0.001). In osteoporotic subjects, in calcaneus and metacarpus, D was higher (1.94±0.03, 1.93±0.03, respectively) than in healthy subjects (1.90±0.02, 1.89±0.02, respectively, p<0.01). In all the subjects, fractal dimension and ultrasound broadband attenuation T-score correlated significantly in calcaneus and metacarpus (p<0.03 and p<0.02, respectively). CONCLUSIONS: Parameters based on a combination of ultrasonic examination and fractal analysis on radiographic images may add useful structural information regarding the patients' skeleton using non invasive procedures.


Asunto(s)
Huesos/diagnóstico por imagen , Fractales , Osteoporosis/diagnóstico por imagen , Anciano , Calcáneo/diagnóstico por imagen , Estudios de Casos y Controles , Femenino , Fémur/diagnóstico por imagen , Falanges de los Dedos de la Mano/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Huesos del Metacarpo/diagnóstico por imagen , Persona de Mediana Edad , Radiografía , Ultrasonografía
8.
Scand J Clin Lab Invest ; 68(6): 479-83, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18609101

RESUMEN

BACKGROUND: Sarcoidosis is a multisystemic granulomatous disease with an unpredictable clinical course characterized by accumulation of activated proliferating T lymphocytes and mononuclear phagocytes in affected organs. AIMS AND METHODS: The aims of this study were to describe the clinical, radiological and immunological features of a population of sarcoidosis patients followed at the Sarcoidosis Regional Centre in Siena and to analyse chitotriosidase and sIL-2R concentrations in serum of these patients in order to understand their potential as disease markers. RESULTS: Chitotriosidase and sIL-2R concentrations in serum of sarcoidosis patients were found to be significantly higher than in healthy controls (p<0.01) and a positive correlation between the two markers was documented for the first time. Moreover, chitotriosidase and sIL-2R were expressed differently in different radiographic stages of the disease. CONCLUSION: Chitotriosidase and sIL-2R are two markers of sarcoidosis of different origin, the values of which show a correlation in these patients; they are easily detectable in serum and could be useful clinical markers of progression.


Asunto(s)
Hexosaminidasas/metabolismo , Receptores de Interleucina-2/sangre , Sarcoidosis/sangre , Sarcoidosis/patología , Biomarcadores/sangre , Femenino , Salud , Humanos , Masculino , Persona de Mediana Edad , Sarcoidosis/enzimología , Fumar , Solubilidad
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