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Wireless sensor networks (WSN) allow to exchange information and to take immediate and remote actions in natural, industrial, military or domestic environment systems. These networks are vulnerable to cyber-attacks, hence, they are vulnerable to being intercepted, interrupted or modified. However, for the last twenty years, the amount of information exchanged through communication networks around the world has considerably increased and thus its vulnerability. As a result, encryption algorithms are fundamental to protect information. In this context, security, performance and energy consumption become a paramount design factor for an engineer when designing and implementing WSNs. It is not an easy task to reach an optimal balance between these factors. In this paper, we evaluate three well-known symmetric encryption algorithms in an embedded development platform: the ARDUINO MEGA 2560. Our experiment measures the algorithms encryption average execution time and energy consumption. Additionally, we measure the impact of the channels of a small wireless sensor network with two nodes. The evaluation demonstrates the feasibility of implementing cryptographic algorithms in devices with limited resources such as memory, computing power and life span (energy consumption). Furthermore, the low impact on the network channels when comparing unencrypted communication vs encrypted communication evidence the potential of symmetric encryption algorithms.

Resumen El presente estudio realizó un análisis de la influencia que ejercen las variaciones del grosor del sustrato dieléctrico y de la posición de las ranuras de microcinta creadas en el parche radiante de una antena de microcinta. El trabajo presentó la simulación mediante el software de optimización automática CST Studio, de una antena para captura de energía de radiofrecuencia empleando el substrato ARLON AD450 con constante dieléctrica de 4.5, pérdidas tangenciales de 0.035 y espesor de 3 mm. En este diseño se aplicaron varias ranuras hasta formar una espira cuadrada. Los resultados obtenidos evidenciaron que al aumentar el espesor del sustrato que separa el plano de tierra del parche radiante, se produce una disminución en las pérdidas de retorno del parámetro (S 11 ) y al mismo tiempo se da un aumento en la ganancia de la antena. La creación de ranuras, el grosor y la ubicación de estas en el parche radiante producen un desplazamiento en la frecuencia de resonancia. Asimismo, el arreglo presentado permite frecuencias de resonancia alrededor de 1.6 GHz, 2.38 GHz, 3.38 GHz y 4.16 GHz, con una ganancia entre 2.48 dB y 7.66 dB. Este diseño de antena permitió mejoras en ganancia y en el patrón de radiación. La creación de ranuras en el parche radiante modificó la distribución de corriente de superficie de la antena y generó nuevas frecuencias de resonancia. Los espacios de aire creados entre el cobre y el substrato mejoraron el rendimiento de la antena, del mismo modo que el espacio ejercido por el substrato entre el plano de tierra y el parche radiante disminuyeron las pérdidas de ganancia en la antena debido a la reducción del cobre cuando se realizan estas ranuras. La antena propuesta presenta un comportamiento multibanda inmediatamente se agregan ranuras en el parche. La evaluación de substratos y estructuras son útiles para el desarrollo de antenas de microcinta integradas para sistemas de recolección de energía de radiofrecuencia. Abstract This study analyses the influence of variations in the thickness of the dielectric substrate and the position of the microstrip slots created in the radiating patch of a microstrip antenna. Automatic optimization software, i.e., CST Studio, was used to simulate an antenna for radio frequency energy harvesting made of ARLON AD450 substrate with a dielectric constant of 4.5, tangential losses of 0.035 and a thickness of 3 mm. In this design, several slots were applied to form a square loop. The results show that, by increasing the thickness of the substrate that separates the ground plane from the radiating patch, the return loss of the (S 11 ) parameter was reduced, and, at the same time, the antenna gain rose. Cutting out slots, as well as their thickness and location in the radiating patch, produced a shift in the antenna’s resonant frequency. Likewise, the array presented here allowed resonant frequencies around 1.6 GHz, 2.38 GHz, 3.38 GHz, and 4.16 GHz, with a gain between 2.48 dB and 7.66 dB. This antenna design produced improvements in gain and radiation pattern. Creating slots in the radiating patch modified the surface current distribution of the antenna and generated new resonant frequencies. The air gaps produced between the copper and the substrate improved the antenna’s performance. Similarly, the spaces created by the substrate between the ground plane and the radiating patch decreased the gain losses in the antenna due to the reduction of the copper caused when the slots were made. The proposed antenna presented a multiband behavior immediately after the slots were added to the patch. Evaluating substrates and structures is useful for developing integrated microstrip antennas for RF energy harvesting systems.

The popularity of unmanned aerial vehicles (UAV) has been constantly increasing during the last years. After being used as war tools by armies around the world, UAVs started being used in multiple civil applications. In the near future, hundreds or even thousands of UAVs will share the airspace with civil and commercial aviation [1]. Hence, UAVs become a new risk factor to consider in aerial security [2]. In this context, the need for researching and developing new intelligent systems capable of reducing the risks is justified. These intelligent systems must be able to optimize and update their flight trajectories to avoid collisions with buildings, mountains, or other airships. Therefore, the route planning method has real-time requirements. It must obtain the UAV orientation in real time, not only to reach the target but also to avoid collisions. The problem increases when the environment changes dynamically or when there is not a predefined flight route to follow [3].

Este artículo presenta dos rectennas (Rectifying Antennas) de bajo costo y de doble banda para recolectar energía de RF de las bandas GSM-850, GSM-1900 y UMTS-2100 MHz. Ambas rectennas se basan en antenas monopolos con plano de tierra de tipo Defected Grounded Structure (DGS). La primera está diseñada con un anillo resonador cuadrado, el ancho de banda se encuentra entre 73.4 y 145 MHz, con una ganancia de 2.29 y 3.53 dBi. La segunda presenta un ancho de banda de 86 y 124.8 MHz con una ganancia de 1 y 3.8 dBi. Además, un rectificador de triple banda con un diodo Schottky HSMS-286C para mejorar la eficiencia de conversión de potencia de RF a CC. Los resultados de la medición muestran que se ha logrado recolectar entre 150 y 308 mV de CC durante 8 horas a 50 metros de una estación base de telefonía, en un total de 86 horas continuas de exposición a esta estación se ha obtenido un voltaje de CC que varía entre 4 y 4.50 voltios de energía de RF ambiental.

[EN] Unmanned Aerial Vehicles (UAV) have oered alternatives for applications in which human integrity is compromised. In this sense, the need of increasing autonomy in these vehicles presents an alternative to artificial intelligence areas to enhance navigation capacities through several environments. This article presents an evaluation for estimating inclination and orientation, using automatic learning algorithms for a dynamic multi-rotor plant. To do so, an experiment is proposed to collect the data from multiple IMU sensors over an UAV main board, and submitted to dierent inclinations before achieving the classification task. The reported results using k nearest neighbors (k - NN), support vector machines (S VM) and Bayes show eficiency during the recognition, obtaining an accuracy score up to 99 %. Besides, the algoritms could be combined along with robust control techniques, which is ideal for implementation in embedded systems with low processing capacities., [ES] Los vehículos aéreos no tripulados (UAV) ofrecen alternativas para diversas aplicaciones en las que se compromete la integridad humana. En este sentido, la necesidad de incrementar la autonomía de estos vehículos presenta una alternativa al área de inteligencia artificial para aumentar las capacidades de navegación en diversos entornos. Este artículo presenta una evaluación para estimación de inclinación y orientación, utilizando algoritmos de aprendizaje automático para una planta dinámica con múltiples rotores. Para esto se propone un experimento para recopilar datos de unidades de medición inercial (IMU) sobre la placa de un UAV, y sometidos a diferentes inclinaciones antes de lograr la tarea de clasificación. Los resultados reportados usando los algoritmos de k vecinos más cercanos (k-NN), máquinas de soporte vectorial (SVM) y de Bayes muestran eficiencia en el reconocimiento, obteniendo una precisión hasta del 99 %. Además, estos algoritmos podrían combinarse con técnicas de control robustas, ideal para la implementación en sistemas con capacidades de procesamiento limitadas.

The performance and power consumption are essential when designing and implementing embedded systems for flight control unmanned aerial vehicles (UAV). One of the main challenges that designers face is finding the balance between robust performance, small size and low power consumption. Additionally, in unfamiliar surroundings it is important that the UAV has a system of route planning, which allows determining the direction to a target. We evaluated tres embedded microcontrollers based systems running a route planner in real time, which uses the algorithm of PSO optmizacion.

Visible light communication system arises to create wireless links using light-emitting diode luminaires. The literature reports multiple works in visible light communication using different development tools. However, most are based on signal processors, field-programmable gate Arrays and proprietary software to develop the algorithms. This paper presents a wireless optical communication system using amplitude modulation on both hardware and free software tools. An algorithm for amplitude modulation/demodulation in GNU Radio installed on the Raspberry Pi development card was created. Additionally, an optical transmitter based on a white light-emitting diode and a receiver with a solar panel was designed. Communication experiments were performed based on the distance of the system link. The results report that the optimal response of amplitude modulation/demodulation was achieved with a solar panel response of --68 dBmV at maximum distance of 3 m between transmitter and receiver at usual illumination levels, and the potential to use free hardware and software tools in the implementation and analysis of optical wireless communication systems.

Purpose: To validate and evaluate the accuracy of an algorithm for the identification of nonmetallic intraocular foreign body composition based on computed tomography and magnetic resonance imaging. Methods: An algorithm for the identification of 10 nonmetallic materials based on computed tomography and magnetic resonance imaging has been previously determined in an ex vivo porcine model. Materials were classified into 4 groups (plastic, glass, stone, and wood). The algorithm was tested by 40 ophthalmologists, which completed a questionnaire including 10 sets of computed tomography and magnetic resonance images of eyes with intraocular foreign bodies and were asked to use the algorithm to identify their compositions. Rates of exact material identification and group identification were measured. Results: Exact material identification was achieved in 42.75% of the cases, and correct group identification in 65%. Using the algorithm, 6 of the materials were exactly identified by over 50% of the participants, and 7 were correctly classified according to their groups by over 75% of the materials. Discussion: The algorithm was validated and was found to enable correct identification of nonmetallic intraocular foreign body composition in the majority of cases. This is the first study to report and validate a clinical tool allowing intraocular foreign body composition based on their appearance in computed tomography and magnetic resonance imaging, which was previously impossible.

High-grade gliomas constitute a group of aggressive CNS cancers that have high morbidity and mortality rates. Despite extensive research, current therapeutic approaches enable survival beyond 2 years in rare cases only. Thrombin and its main CNS target, protease-activated receptor-1, have been implicated in tumor progression and brain edema. Our aim was to study protease-activated receptor-1 (PAR-1) protein expression and thrombin-like activity levels in both in vitro and in vivo models of glioblastoma and correlate them with the volume of the surrounding edema. We measured the presence of PAR-1 protein using fluorescence immunohistochemistry and assessed thrombin activity in various glial and non-glial cell lines and in a CNS-1 glioma rat model using a thrombin-specific fluorescent assay. Thrombin activity was found to be highly elevated in various high-grade glioma cell lines as well as in non-glial malignant cell lines. In the CNS-1 glioma model, the level of PAR-1 fluorescence in the tumor was significantly elevated compared to adjacent regions of reactive gliosis or distant brain areas. The elevated level of thrombin activity observed in the high-grade glioma positively correlated with tumor-induced brain edema. In conclusion, thrombin is secreted from glioma cells and PAR-1 may be a new biological marker for high-grade gliomas.

Hadas Skaat,1 Enav Corem-Slakmon,1 Igor Grinberg,1 David Last,2 David Goez,2 Yael Mardor,2,3 Shlomo Margel1 1Department of Chemistry, Bar-Ilan Institute of Nanotechnology and Advanced Materials, Ramat-Gan, Israel; 2Advanced Technology Center, Sheba Medical Center, Tel-Hashomer, Ramat-Gan, Israel; 3Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel Abstract: Amyloid-β (Aβ) peptide is the main fibrillar component of plaque deposits found in brains affected by Alzheimer's disease (AD) and is related to the pathogenesis of AD. Passive anti-Aβ immunotherapy has emerged as a promising approach for the therapy of AD, based on the administration of specific anti-Aβ monoclonal antibodies (aAβmAbs) to delay Aβ aggregation in the brain. However, the main disadvantage of this approach is the required readministration of the aAβmAbs at frequent intervals. There are only a few reports describing in vitro study for the immobilization of aAβmAbs to nanoparticles as potential targeting agents of Aβ aggregates. In this article, we report the immobilization of the aAβmAb clone BAM10 to near-infrared fluorescent maghemite nanoparticles for the inhibition of Aβ40 fibrillation kinetics and the specific detection of Aβ40 fibrils. The BAM10-conjugated iron oxide nanoparticles were well-characterized, including their immunogold labeling and cytotoxic effect on PC-12 (pheochromocytoma cell line). Indeed, these antibody-conjugated nanoparticles significantly inhibit the Aβ40 fibrillation kinetics compared with the same concentration, or even five times higher, of the free BAM10. This inhibitory effect was confirmed by different assays such as the photo-induced crosslinking of unmodified proteins combined with sodium dodecyl sulfate–polyacrylamide gel electrophoresis. A cell viability assay also confirmed that these antibody-conjugated nanoparticles significantly reduced the Aβ40-induced cytotoxicity to PC-12 cells. Furthermore, the selective labeling of the Aβ40 fibrils with the BAM10-conjugated near-infrared fluorescent iron oxide nanoparticles enabled specific detection of Aβ40 fibrils ex vivo by both magnetic resonance imaging and fluorescence imaging. This study highlights the immobilization of the aAβmAb to dual-modal nanoparticles as a potential approach for aAβmAb delivery, eliminating the issue of readministration, and contributes to the development of multifunctional agents for diagnosis and therapy of AD. Keywords: near-infrared fluorescent γ-Fe2O3 nanoparticles, protein folding, amyloid-β peptide, passive immunotherapy, neurodegenerative diseases

Type 2 diabetes (T2D) is associated with increased risk of Alzheimer's disease (AD). There is evidence for impaired blood–brain barrier (BBB) in both diseases, but its role in the interplay between them is not clear. Here, we investigated the effects of high‐fat diet (HFD), a model for T2D, on the Tg2576 mouse model of AD, in regard to BBB function. We showed that HFD mice had higher weight, more insulin resistance, and higher serum HDL cholesterol levels, primarily in Tg2576 mice, which also had higher brain lipids content. In terms of behavior, Tg2576 HFD mice were less active and more anxious, but had better learning in the Morris Water Maze compared to Tg2576 on regular diet. HFD had no effect on the level of amyloid beta 1–42 in the cortex of Tg2576 mice, but increased the transcription level of insulin receptor in the hippocampus. Tg2576 mice on regular diet demonstrated more BBB disruption at 8 and 12 months accompanied by larger lateral ventricles volume in contrast to Tg2576 HFD mice, whose BBB leakage and ventricular volume were similar to wild‐type (WT) mice. Our results suggest that in AD, HFD may promote better cognitive function through improvements of BBB function and of brain atrophy but not of amyloid beta levels. Lipid metabolism in the CNS and peripheral tissues and brain insulin signaling may underlie this protection.

This project presents the results of using velocity control through ultrasound sensors and accelerometers to detect objects. They are associated to a fuzzy controller to prevent collisions in indoor spaces. Implementing this anti-collision model leads to a more secure aerial robots navigation in indoor spaces.

PURPOSE To perform a comprehensive comparative analysis of nonmetallic intraocular foreign bodies (IOFBs) using computed tomography (CT) and magnetic resonance imaging (MRI). METHODS An ex vivo model of porcine eyes was used to study IOFBs consisting of 10 different materials: plastic, eyeglass lens, bottle glass, windshield glass, porcelain, gravel stone, concrete, wood, thorn, and pencil graphite. The study included 30 eyes with IOFBs and 6 control eyes. Each eye was scanned by CT and MRI. Images were analyzed by three-dimensional viewing software to determine distinguishing characteristics for each material. RESULTS Analysis of MRI and CT scans yielded distinguishing characteristics for each of the 10 materials, and this information was integrated into a clinical algorithm that enables their distinction. More materials were identified by MRI than by CT, and smaller IOFB size was associated with lower detectability. Review of CT and head-coil MRI scans by masked specialists yielded a 95% agreement rate and allowed detection of most IOFBs. CONCLUSION Magnetic resonance imaging was superior to CT in IOFB detection. Using these modalities, a set of distinguishing characteristics was established for the identification of the 10 studied materials. We recommend MRI to be part of the evaluation of patients with a suspected IOFB, after CT to rule out metallic IOFBs.

Identificar las causas por las cuales los niños y niñas del grado pre-jardín del centro educativo pompones de colores no son estimulados en el área motriz y las repercusiones que esta carencia trae a su desarrollo integral. La calidad de la atención a los niños de cero a cinco años es una constante preocupación de la Educación Preescolar. Para lograrlo es preciso atender a la diversidad de niños comprendidos en estas edades, dentro de los cuales se encuentran los infantes con factores de riesgo de retraso mental, para los cuales no existe el diseño de un proceso pedagógico integral que contemple la posibilidad que tienen de sufrir retardos o desviaciones en su desarrollo. Se hace necesario el establecimiento de una estrategia pedagógica para la dirección del proceso de estimulación temprana a los niños de cero a cinco años con factores de riesgo de retraso mental, sustentada en un modelo pedagógico para la estimulación temprana encaminado a la prevención de los retardos en el desarrollo. En el trabajo se presenta la concepción pedagógica que sustenta el modelo, sus principios, métodos y relaciones que posibilitaron además, la elaboración un programa de estimulación temprana en el que se incluyen manifestaciones de la filogénesis como contenidos para estimular el desarrollo. La aplicación de diversos métodos de investigación posibilitó la caracterización del objeto que se investiga, la elaboración de la propuesta y su valoración a través del estudio de casos y el criterio de expertos.

2078 Background: Changes in enhancement seen in post treatment brain MRIs in primary and secondary brain malignancies often mimic tumor progression (pseudoprogression, radiation necrosis). Conventional MRI cannot differentiate tumor progression from treatment related effects resulting in suboptimal patient management. Methods: The application of delayed contrast extravasation MRI for depicting unique vessels characteristics with high resolution and high sensitivity to subtle BBB disruption is demonstrated in 17 GBM and 15 brain metastases patients undergoing standard chemoradiation and radiosurgery respectively. Results: 2 primary vessel function populations were defined: a slow population where contrast clearance from the tissue was slower than accumulation, and a fast population where clearance was faster than accumulation. Ten stereotactic biopsies acquired from GBM patients showed complete correlation with the maps, confirming the discrimination between fast population regions, reflecting morphological active tumor and slow regions reflecting necrosis/treatment-induced changes. Typical fast population vessel morphology consisted of proliferating endothelial cells, dilated lumen, peri vascular fibrosis and glumeroloid vessels, while slow regions consisted of necrotic vessels, in agreement with the observed MRI vessel function. The fast component volume 3 weeks post treatment was significantly correlated with the fast volume 4 (r2=0.84, p2=0.84, p