Superparamagnetic Poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV) nanoparticles for biomedical applications

Indexación: ScieloBackground: The progress in material science and the recent advances in biodegradable/biocompatible polymers and magnetic iron oxide nanoparticles have led to develop innovative diagnostic and therapeutic strategies for diseases based on multifunctional nanoparticles, which include contrast medium for magnetic resonance imaging, agent for hyperthermia and nanocarriers for targeted drug delivery. The aim of this work is to synthesize and characterize superparamagnetic iron oxide (magnetite), and to encapsulate them into poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanoparticles for biomedical applications. Results: The magnetite nanoparticles were confirmed by X-ray diffraction and exhibited a size of 22.3 ± 8.8 nm measured by transmission electron microscopy (TEM). Polymeric PHBV nanoparticles loaded with magnetite (MgNPs) were analyzed using dynamic light scattering and showed a size of 258.6 ± 35.7 nm and a negative zeta potential (-10.8 ± 3.5 mV). The TEM examination of MgNPs exhibited a spherical core-shell structure and the magnetic measurements showed in both, non-encapsulated magnetite and MgNPs, a superparamagnetic performance. Finally, the in vitro studies about the magnetic retention of MgNPs in a segment of small intestine of rats showed an active accumulation in the region of the magnetic field. Conclusions: The results obtained make the MgNPs suitable as potential magnetic resonance imaging contrast agents, also promoting hyperthermia and even as potential nanocarriers for site-specific transport and delivery of drugs. Keywords: hyperthermia, magnetic resonance image (MRI), magnetite, PHBV, polymeric nanoparticles.http://ref.scielo.org/cxt57

Worker’s physical fatigue classification using neural networks

Physical fatigue is not only an indication of the user’s physical condition and/or need for sleep or rest, but can also be a significant symptom of various diseases. This fatigue affects the performance of workers in jobs that involve some continuous physical activity, and is the cause of a large proportion of accidents at work. The physical fatigue is commonly measured by the perceived exertion (RPE). Many previous studies have attempted to continuously monitor workers in order to detect the level of fatigue and prevent these accidents, but most have used invasive sensors that are difficult to place and prevent the worker from performing their tasks correctly. Other works use activity measurement sensors such as accelerometers, but the large amount of information obtained is difficult to analyse in order to extract the characteristics of each fatigue state. In this work, we use a dataset that contains data from inertial sensors of several workers performing various activities during their working day, labelled every 10 min based on their level of fatigue using questionnaires and the Borg fatigue scale. Applying Machine Learning techniques, we design, develop and test a system based on a neural network capable of classifying the variation of fatigue caused by the physical activity collected every 10 min; for this purpose, a feature extraction is performed after the time decomposition done with the Discrete Wavelet Transform (DWT). The results show that the proposed system has an accuracy higher than 92% for all the cases, being viable for its application in the proposed scenario.European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)Consejería de Economía, Conocimiento, Empresas y Universidad (Junta de Andalucía) US-126371

Secure Sensor Prototype Using Hardware Security Modules and Trusted Execution Environments in a Blockchain Application: Wine Logistic Use Case

The security of Industrial Internet of Things (IIoT) systems is a challenge that needs to be addressed immediately, as the increasing use of new communication paradigms and the abundant use of sensors opens up new opportunities to compromise these types of systems. In this sense, technologies such as Trusted Execution Environments (TEEs) and Hardware Security Modules (HSMs) become crucial for adding new layers of security to IIoT systems, especially to edge nodes that incorporate sensors and perform continuous measurements. These technologies, coupled with new communication paradigms such as Blockchain, offer a high reliability, robustness and good interoperability between them. This paper proposes the design of a secure sensor incorporating the above mentioned technologies—HSMs and a TEE—in a hardware device based on a dual-core architecture. Through this combination of technologies, one of the cores collects the data extracted by the sensors and implements the security mechanisms to guarantee the integrity of these data, while the remaining core is responsible for sending these data through the appropriate communication protocol. This proposed approach fits into the Blockchain networks, which act as an Oracle. Finally, to illustrate the application of this concept, a use case applied to wine logistics is described, where this secure sensor is integrated into a Blockchain that collects data from the storage and transport of barrels, and a performance evaluation of the implemented prototype is providedEuropean Union’s Horizon Europe research and innovation program through the funding project “Cognitive edge-cloud with serverless computing” (EDGELESS) under grant agreement number 101092950FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades under Project B-TIC-588-UGR2

Spatial characterization of climatic variables for Arica-Parinacota and Tarapacá, Chile using topoclimatic analysis

In the present study, models were developed to determine the monthly and annual spatio-temporal variation of temperature, precipitation, and solar radiation based on topoclimatic analysis of Arica-Parinacota and Tarapacá in northern Chile. To construct the equations of the topoclimatic model, the data from meteorological stations and physiographic factors (latitude, longitude, altitude, and distance to bodies of water) obtained from a digital terrain model with a resolution of 90 m were compiled in a database. The equations of the topoclimatic model were generated by a stepwise regression with a backward selection technique. The equations for average monthly temperature, precipitation, and solar radiation were determined by linear combinations. The results were statistically significant with coefficients of determination greater than 90%, in addition to being greater than the existing climate databases for this area

Diseño y desarrollo de sistema IoT para el control y monitorización de personas

Las TIC han avanzado sirviendo de apoyo a diferentes servicios, sin ser la salud una excepción. La telemedicina soluciona problemas como la demanda de atención médica o la asistencia. La telemonitorización destaca por su comodidad para controlar el estado del paciente a distancia; sin embargo, estos sistemas son costosos e implican portar un dispositivo voluminoso. En este trabajo se realiza el diseño e implementación de un sistema de monitorización basado en IoT, haciendo uso de una placa de bajo costo y sensores de medición de constantes vitales, que se conectan al dispositivo móvil del usuario para enviar información a distancia y en tiempo real, además de registrar la evolución y visualizar el estado en el dispositivo móvil. De igual forma y gracias al sistema IoT, se registra la posición GPS, que será transmitida al contacto de emergencia en caso de detectar una variación peligrosa de las constantes vitales

Índice de potencial productivo del suelo aplicado a tres fincas ganaderas de ladera en el valle del cauca, colombia

Se evaluó el potencial productivo-PPS en suelos volcánicos de ladera de tres fincas lecheras (Nogales, Refugio y Horizonte) en Bolívar, Valle del Cauca, utilizando un indicador mixto de propiedades (físicas, químicas y de actividad biológica del suelo), conductividad térmica y el efecto de manejo con los índices de Compactación (IC) y Fertilidad (IF). Se utilizó un diseño completamente al azar con tres tratamientos y cinco repeticiones de acuerdo con zonas homogéneas de humedad edáfica. IC fue moderado en todos los casos y PPS fue medio en las tres fincas no obstante el IF fuera alto en Nogales y moderado en Refugio y Horizonte. La correlación lineal múltiple entre parámetros indicó que IC e IF influyeron aproximadamente en un 70 % sobre PPS

Evidence of past seisms in Cusco (Peru) and Tzintzuntzan (Mexico): cultural relations

[ENG] (Evidence of ancient seisms in Cusco, Peru and Tzintzuntzan, Mexico and their cultural relations) At first sight the ancient pre-Columbian cultures seem to have had no awareness of seisms. Purhepecha and Andean cultures nevertheless not only show awareness of these, but also similitude between their anti seismic building techniques. This work exposes clear evidence of coseismic ruptures found In Cusco and in Tzintzuntzan-Patzcuaro. More profound research could nevertheless be helpful to reveal sceneries which are for their most part unknown to current generations

The polypeptides COX2A and COX2B are essential components of the mitochondrial cytochrome c oxidase of Toxoplasma gondii

AbstractTwo genes encoding cytochrome c oxidase subunits, Cox2a and Cox2b, are present in the nuclear genomes of apicomplexan parasites and show sequence similarity to corresponding genes in chlorophycean algae. We explored the presence of COX2A and COX2B subunits in the cytochrome c oxidase of Toxoplasma gondii. Antibodies were raised against a synthetic peptide containing a 14-residue fragment of the COX2A polypeptide and against a hexa-histidine-tagged recombinant COX2B protein. Two distinct immunochemical stainings localized the COX2A and COX2B proteins in the parasite's mitochondria. A mitochondria-enriched fraction exhibited cyanide-sensitive oxygen uptake in the presence of succinate. T. gondii mitochondria were solubilized and subjected to Blue Native Electrophoresis followed by second dimension electrophoresis. Selected protein spots from the 2D gels were subjected to mass spectrometry analysis and polypeptides of mitochondrial complexes III, IV and V were identified. Subunits COX2A and COX2B were detected immunochemically and found to co-migrate with complex IV; therefore, they are subunits of the parasite's cytochrome c oxidase. The apparent molecular mass of the T. gondii mature COX2A subunit differs from that of the chlorophycean alga Polytomella sp. The data suggest that during its biogenesis, the mitochondrial targeting sequence of the apicomplexan COX2A precursor protein may be processed differently than the one from its algal counterpart

Construcción de un prototipo electrónico de control químico de emisiones de gases contaminantes dentro de vehículos

A nivel mundial, las emisiones de gases de vehículos provocan grandes pérdidas humanas. El objetivo de la presente investigación fue la construcción de un prototipo de supervisión y alerta de nivel de gases contaminantes dentro de vehículos con sistema de combustión. El prototipo consta de 5 bloques y supervisa la calidad de aire del habitáculo con sensores que miden monóxido de carbono (CO), óxidos de nitrógeno (NOx) y benceno, mostrando la información obtenida, mensajes en casos extremos, además de activar dispositivos según el nivel calculado. El estudio se basó en un análisis histórico bibliográfico de datos relacionados con la problemática; mediante pruebas de calentamiento y calibración de los sensores, se determinó que el prototipo necesita 5 minutos para estabilizar sus lecturas, con un error absoluto de ±1,65 %; al calcular la repetitividad con el coeficiente de variación se obtiene un valor máximo de 3,93 %. El prototipo implementado es confiable para supervisar la concentración de gases en el habitáculo mediante la activación de actuadores sonoros y de circulación de aire