522 research outputs found

    Algorithmic Efficiency of Stroke Gesture Recognizers: a Comparative Analysis

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    Gesture interaction is today recognized as a natural, intuitive way to execute commands of an interactive system. For this purpose, several stroke gesture recognizers become more efficient in recognizing end-user gestures from a training set. Although the rate algorithms propose their rates of return there is a deficiency in knowing which is the most recommended algorithm for its use. In the same way, the experiments known by the most successful algorithms have been carried out under different conditions, resulting in non-comparable results. To better understand their respective algorithmic efficiency, this paper compares the recognition rate, the error rate, and the recognition time of five reference stroke gesture recognition algorithms, i.e., 1,1, P, Q,!FTL,andPennyPincher,onthreediversegesturesets,i.e.,NicIcon,HHReco,andUtopianoAlphabet,inauserindependentscenario.Similarconditionswereappliedtoallalgorithms,tobeexecutedunderthesamecharacteristics.Forthealgorithmsstudied,themethodagreedtoevaluatetheerrorrateandperformancerate,aswellastheexecutiontimeofeachofthesealgorithms.AsoftwaretestingenvironmentwasdevelopedinJavaScripttoperformthecomparativeanalysis.Theresultsofthisanalysishelprecommendingarecognizerwhereitturnsouttobethemostefficient.!FTL(NLSD)isthebestrecognitionrateandthemostefficientalgorithmfortheHHrecoandNicIcondatasets.However,PennyPincherwasthefasteralgorithmforHHrecodatasets.Finally,Q, !FTL, and Penny Pincher, on three diverse gesture sets, i.e., NicIcon, HHReco, and Utopiano Alphabet, in a user-independent scenario. Similar conditions were applied to all algorithms, to be executed under the same characteristics. For the algorithms studied, the method agreed to evaluate the error rate and performance rate, as well as the execution time of each of these algorithms. A software testing environment was developed in JavaScript to perform the comparative analysis. The results of this analysis help recommending a recognizer where it turns out to be the most efficient. !FTL (NLSD) is the best recognition rate and the most efficient algorithm for the HHreco and NicIcon datasets. However, Penny Pincher was the faster algorithm for HHreco datasets. Finally, 1 obtained the best recognition rate for the Utopiano Alphabet dataset

    Three-dimensional planar object tracking with sub-pixel accuracy

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    Subpixel techniques are commonly used to increase the spatial resolution in tracking tasks. Object tracking with targets of known shape permits obtaining information about object position and orientation in the three-dimensional space. A proper selection of the target shape allows us to determine its position inside a plane and its angular and azimuthal orientation under certain limits. Our proposal is demonstrated both numerical and experimentally and provides an increase the accuracy of more than one order of magnitude compared to the nominal resolution of the sensor. The experiment has been performed with a high-speed camera, which simultaneously provides high spatial and temporal resolution, so it may be interesting for some applications where this kind of targets can be attached, such as vibration monitoring and structural analysis.The authors acknowledge the support of the Spanish Ministerio de Economía y Competitividad through the project BIA2011-22704 and the Generalitat Valenciana through the projects GV/2013/009 and PROMETEO/ 2011/021. A. B. Roig acknowledges a grant from Cajamurcia

    Dopamine D1/D5 Receptors in the Retrosplenial Cortex Are Necessary to Consolidate Object Recognition Memory

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    The retrosplenial cortex (RSC) has been widely related to spatial and contextual memory. However, we recently demonstrated that the anterior part of the RSC (aRSC) is required for object recognition (OR) memory consolidation. In this study, we aimed to analyze the requirement of dopaminergic inputs into the aRSC for OR memory consolidation in male rats. We observed amnesia at 24-h long-term memory when we infused SCH23390, a D1/D5 dopamine receptors antagonist, into aRSC immediately after OR training session. However, the same infusion had no effect on OR short-term memory. Then, we analyzed whether the ventral tegmental area (VTA) is necessary for OR consolidation. VTA inactivation by intra-VTA administration of muscimol, a GABAA agonist, immediately after an OR training session induced amnesia when animals were tested at 24 h. Moreover, we observed that this VTA inactivation-induced amnesia was reversed by the simultaneous intra-aRSC delivery of SKF38393, a D1/D5 receptor agonist. Altogether, our results suggest that VTA dopaminergic inputs to aRSC play an important modulatory role in OR memory consolidation.Fil: de Landeta, Ana Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Medina, Jorge Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina. Instituto Tecnológico de Buenos Aires; ArgentinaFil: Katche, Cynthia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina. Instituto Tecnológico de Buenos Aires; Argentin

    Compact Integration of a GSM-19 Magnetic Sensor with High-Precision Positioning using VRS GNSS Technology

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    Magnetic data consists of a sequence of collected points with spatial coordinates and magnetic information. The spatial location of these points needs to be as exact as possible in order to develop a precise interpretation of magnetic anomalies. GPS is a valuable tool for accomplishing this objective, especially if the RTK approach is used. In this paper the VRS (Virtual Reference Station) technique is introduced as a new approach for real-time positioning of magnetic sensors. The main advantages of the VRS approach are, firstly, that only a single GPS receiver is needed (no base station is necessary), reducing field work and equipment costs. Secondly, VRS can operate at distances separated 50–70 km from the reference stations without degrading accuracy. A compact integration of a GSM-19 magnetometer sensor with a geodetic GPS antenna is presented; this integration does not diminish the operational flexibility of the original magnetometer and can work with the VRS approach. The coupled devices were tested in marshlands around Gandia, a city located approximately 100 km South of Valencia (Spain), thought to be the site of a Roman cemetery. The results obtained show adequate geometry and high-precision positioning for the structures to be studied (a comparison with the original low precision GPS of the magnetometer is presented). Finally, the results of the magnetic survey are of great interest for archaeological purposes

    High-speed video-oculography applied to assess pupil light reflex

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    Póster presentado en el VII European/ I World Meeting in Visual and Physiological OpticsEye response to light exposure is usually described through the pupillary light reflex, which controls the pupil diameter and allows for testing the sensory and motor functions of the eye. We have arranged an experimental setup and developed a procedure in order to improve the video-oculography experiment through high-speed imaging. The technique has been applied over eleven people distinguishing between consensual and direct pupillary light reflexes and analyzing the eye dominance. We found no significant differences. Moreover, obtained time parameters describing the pupil light reflex agree with those from literature.The authors acknowledge the projects BIA2011-22704, GV/2013/009 and PROMETEO/ 2011/021. A. B. Roig acknowledges a grant from Cajamurcia

    A high-resolution binocular video-oculography system: assessment of pupillary light reflex and detection of an early incomplete blink and an upward eye movement

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    Background: The pupillary light reflex characterizes the direct and consensual response of the eye to the perceived brightness of a stimulus. It has been used as indicator of both neurological and optic nerve pathologies. As with other eye reflexes, this reflex constitutes an almost instantaneous movement and is linked to activation of the same midbrain area. The latency of the pupillary light reflex is around 200 ms, although the literature also indicates that the fastest eye reflexes last 20 ms. Therefore, a system with sufficiently high spatial and temporal resolutions is required for accurate assessment. In this study, we analyzed the pupillary light reflex to determine whether any small discrepancy exists between the direct and consensual responses, and to ascertain whether any other eye reflex occurs before the pupillary light reflex. Methods: We constructed a binocular video-oculography system two high-speed cameras that simultaneously focused on both eyes. This was then employed to assess the direct and consensual responses of each eye using our own algorithm based on Circular Hough Transform to detect and track the pupil. Time parameters describing the pupillary light reflex were obtained from the radius time-variation. Eight healthy subjects (4 women, 4 men, aged 24–45) participated in this experiment. Results: Our system, which has a resolution of 15 microns and 4 ms, obtained time parameters describing the pupillary light reflex that were similar to those reported in previous studies, with no significant differences between direct and consensual reflexes. Moreover, it revealed an incomplete reflex blink and an upward eye movement at around 100 ms that may correspond to Bell’s phenomenon. Conclusions: Direct and consensual pupillary responses do not any significant temporal differences. The system and method described here could prove useful for further assessment of pupillary and blink reflexes. The resolution obtained revealed the existence reported here of an early incomplete blink and an upward eye movement.The authors acknowledge the support of the Spanish Ministerio de Economía y Competitividad through the project BIA2011-22704 and the Generalitat Valenciana through the projects GV/2013/009 and PROMETEO/2011/021. A. B. Roig acknowledges a grant from Cajamurcia

    Anterior retrosplenial cortex is required for long-term object recognition memory

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    The retrosplenial cortex (RSC) is implicated on navigation and contextual memory. Lesions studies showed that the RSC shares functional similarities with the hippocampus (HP). Here we evaluated the role of the anterior RSC (aRSC) in the "what" and "where" components of recognition memory and contrasted it with that of the dorsal HP (dHP). Our behavioral and molecular findings show functional differences between the aRSC and the dHP in recognition memory. The inactivation of the aRSC, but not the dHP, impairs the consolidation and expression of the "what" memory component. In addition, object recognition task is accompanied by c-Fos levels increase in the aRSC. Interestingly, we found that the aRSC is recruited to process the "what" memory component only if it is active during acquisition. In contrast, both the aRSC and dHP are required for encoding the "where" component, which correlates with c-Fos levels increase. Our findings introduce a novel role of the aRSC in recognition memory, processing not only the "where", but also the "what" memory component.Fil: de Landeta, Ana Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Pereyra, Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Medina, Jorge Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Katche, Cynthia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentin

    MTORC1 controls long-term memory retrieval

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    Understanding how stored information emerges is a main question in the neurobiology of memory that is now increasingly gaining attention. However, molecular events underlying this memory stage, including involvement of protein synthesis, are not well defined. Mammalian target of rapamycin complex 1 (mTORC1), a central regulator of protein synthesis, has been implicated in synaptic plasticity and is required for memory formation. Using inhibitory avoidance (IA), we evaluated the role of mTORC1 in memory retrieval. Infusion of a selective mTORC1 inhibitor, rapamycin, into the dorsal hippocampus 15 or 40 min but not 3 h before testing at 24 h reversibly disrupted memory expression even in animals that had already expressed IA memory. Emetine, a general protein synthesis inhibitor, provoked a similar impairment. mTORC1 inhibition did not interfere with short-term memory retrieval. When infused before test at 7 or 14 but not at 28 days after training, rapamycin impaired memory expression. mTORC1 blockade in retrosplenial cortex, another structure required for IA memory, also impaired memory retention. In addition, pretest intrahippocampal rapamycin infusion impaired object location memory retrieval. Our results support the idea that ongoing protein synthesis mediated by activation of mTORC1 pathway is necessary for long but not for short term memory.Fil: Pereyra, Magdalena. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Katche, Cynthia Lorena. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Landeta, Ana Belén. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Medina, Jorge Horacio. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Programa de prevención de la depresión en el anciano mediante terapia asistida con animales

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    El envejecimiento poblacional, el aumento de la prevalencia de depresión en la población anciana y el abandono animal generan la necesidad de establecer este programa de prevención de la depresión en ancianos mediante la terapia asistida con animales.Los objetivos van destinados a abordar ambos problemas sociales.La metodología de este trabajo se basa en la búsqueda bibliográfica en las diferentes bases de datos, en la entrevista a varias protectoras de la provincia de Zaragoza. Además, en este apartado se encuentran los criterios de inclusión de la población diana y los métodos de captación. En el desarrollo se explica en que consiste este proyecto, cuya actividad principal es la realización de paseos con ancianos junto a perros abandonados, también se realizan una serie de sesiones educativas y se establece un grupo de apoyo.En las conclusiones se ultima lo beneficioso que sería la realización de este proyecto y lo fundamental que resulta el papel de enfermería.<br /

    Tomato-antioxidants enhance viability of L. reuteri under gastrointestinal conditions while the probiotic negatively affects bioaccessibility of lycopene and phenols

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    [EN] Changes undergone by tomato-antioxidants during gastrointestinal digestion of raw and fried tomato, with or without presence of the probiotic Lactobacillus reuteri ATCC 55730, were studied. Frying process enhanced the extractability of antioxidant compounds, being their content higher in fried than in raw tomato. In vitro digestion led to a significant loss of antioxidant activity (65 and 75% losses for raw and fried tomato, respectively), and total lycopene (60 and 50% losses for raw and fried tomato, respectively); and promoted trans-cis lycopene isomerization initiated during frying. Bioaccessibility of the antioxidant compounds was within 10% and 30%, being higher for phenolic compounds in raw tomato but lower for total lycopene. Finally, although the presence of Lactobacillus reuteri ATCC 55730 reduced the bioaccessibility of antioxidant compounds, the results suggests that the tomato's antioxidant compounds could have a protective effect against the loss of viability of the probiotic.Authors thanks the Universitat Politecnica de Valencia for the financial support given the research project "Simulacion gastrointestinal para el estudio de las interacciones "ingrediente funcional-matriz alimentaria" y su influencia sobre la biodisponibilidad y funcionalidad" (ref. number: 2814).García Hernández, J.; Hernández Pérez, M.; Peinado Pardo, I.; Andrés Grau, AM.; Heredia Gutiérrez, AB. (2018). Tomato-antioxidants enhance viability of L. reuteri under gastrointestinal conditions while the probiotic negatively affects bioaccessibility of lycopene and phenols. Journal of Functional Foods. 43:1-7. doi:https://doi.org/10.1016/j.jff.2017.12.052S174
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