Repositioning of the inferior alveolar nerve in cases of severe mandibular atrophy. : A clinical case

Implant-based rehabilitation of edentulous mandibular posterior sectors tends to be complicated by the presence of bone atrophy. Following tooth loss, cortical bone suffers greater resorption on the vestibular than on the lingual aspect, and patients typically present narrow and low alveolar crests. In cases of moderate to severe mandibular atrophy, the bone height between the alveolar crest and the dental canal is small, and sometimes limited to only a few millimeters. Implant placement in such situations is very difficult, and implies the risk of inferior alveolar nerve damage. In certain cases bone grafting may be considered to restore the alveolar crest. We present a case of severe mandibular atrophy in which inferior alveolar nerve repositioning and implant placement were carried out. Such nerve repositioning may constitute a treatment alternative in patients with severe posterior sector mandibular atrophy and a consequent risk of dental nerve damage during the placement of dental implants

Aplicación de la Analgesia Quirúrgica Acupuntural en Oftalmología

Se realiza un estudio descriptivo de observación de 395 pacientes con edades entre 41 y 87 años, a quienes se les aplicó la Analgesia Quirúrgica Acupuntural al ser intervenidos por patologías oftálmicas desde abril de 2001 hasta febrero del 2004 en el Hospital Clínico Quirúrgico Docente Miguel Enríquez. Predominaron los pacientes entre 61 y 70 años, del sexo masculino, siendo la hipertensión arterial la patología asociada más frecuente y la catarata, la principal causa de las operaciones. Se demostró 92.6% de efectividad de la técnica durante el transoperatorio, no fue necesario la utilización de anal-gésicos postoperatorios; no se presentaron complicaciones inherentes a la misma con una recuperación rápida y mejoró la calidad de vida de los pacientes, con un ahorro significativo de recursos.Palabras clave: Acupuntura, Analgesia Quirúrgica Acupuntural, Oftalmología.</p

Tintura de lana Hercosett 57 con colorantes Lanasol.

Lana Hercosett 57 es la denominación que se da a la lana que ha sido sometida a un acabado inencogible por medio de la aplicación de una resina de poliamida-epiclorhidrina. Se estudia la influencia de diferentes variables que intervienen en el sistema tintóreo, sobre la absorción y reacción de los colorantes reactivos. α-bromo-acril sobre lana Hercosett 57. Se sigue un tipo de planificación de experiencias según un plan central rotatorio compuesto que permite establecer ecuaciones a superficies de respuesta para absorción y reacción en función de las T variables elegidas que son: tiempo, temperatura, pH, concentración de producto auxiliar, Albegal B y concentración de colorante. Se analiza la influencia de cada variable y las interacciones entre ellas.Hercosett 57 Wool is the denomination given to the wool that has been submitted to a shrink resistant finish by the application of a polyamide-epichlorohydrin. The influence of different variables intervening in the dyeing system on the absortion and the reaction of the α-brornine-acrylamide reactive dyes on Hercosett 57 wool. A typo of planning of experiences is followed after a composite rotatable central desing allowing to establish equations or surfaces of response for the absortion and reaction in function of the 5 variables chosen which are: time, temperature, pH, concentration of the auxiliary product Albegal B and the concentration of the dye. The influence of each variable and the interactions between them are analyzed.Laine Hercosett 57 est la dénomination donnée à la laine qui a été soumise à un finissage irrétrécissable moyennant l'application d'une résine de polyamide-épichlorhydrine. On étudie l'influence de différentes variables qui interviennent dans le système de teinture, sur l'absortion et la réaction des colorants réactifs α-bromo-acrylamide sur la laine Hercosett 57. On suit un type de planification d'expériences suivant un "plan central rotatif composé" qui permet d'établir des équations ou surfaces de réponse pour l'absortion et la réaction en fonction des T variables choisies qui sont: le temps, la température, le pH, la concentration de produit auxiliaire Albegal B et la concentration de colorant. On analyse l'influence de chaque variable ainsi que les interactions entre elles-mêmes.Peer Reviewe

Augmented reality application assessment for disseminating rock art

[EN] Currently, marker-based tracking is the most used method to develop augmented reality (AR) applications (apps). However, this method cannot be applied in some complex and outdoor settings such as prehistoric rock art sites owing to the fact that the usage of markers is restricted on site. Thus, natural feature tracking methods have to be used. There is a wide range of libraries to develop AR apps based on natural feature tracking. In this paper, a comparative study of Vuforia and ARToolKit libraries is carried out, analysing factors such as distance, occlusion and lighting conditions that affect user experience in both indoor and outdoor environments, and eventually the app developer. Our analysis confirms that Vuforia¿s user experience indoor is better, faster and flicker-free whether the images are properly enhanced, but it does not work properly on site. Therefore, the development of AR apps for complex outdoor environments such as rock art sites should be performed with ARToolKit.The authors gratefully acknowledge the support from the Spanish Ministerio de Economia y Competitividad to the project HAR2014-59873-R. Similarly, the authors want to express their gratitude to the General Directorate of Culture and Heritage, Conselleria d'Educacio, Investigacio, Cultura i Esport, Generalitat Valenciana for letting us access and carry out research at the archaeological site.Blanco-Pons, S.; Carrión-Ruiz, B.; Lerma, JL. (2018). Augmented reality application assessment for disseminating rock art. Multimedia Tools and Applications. 78(8):10265-10286. https://doi.org/10.1007/s11042-018-6609-xS1026510286788Alahi A., Ortiz R., Vandergheynst P (2012) FREAK: fast retina keypoint. Comput Vis Pattern Recognit 510–517 . doi: https://doi.org/10.1109/CVPR.2012.6247715Amin D, Govilkar S (2015) Comparative study of augmented reality Sdk’S. 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REVISIÓN DE LAS TÉCNICAS DE REALIDAD AUMENTADA Y REALIDAD VIRTUAL EN EL ARTE RUPESTRE

[EN] The usage of augmented reality (AR) and virtual reality (VR) technologies began to grow when smartphones appeared. Until then, the number of portable devices capable of incorporating these technologies was reduced. Video games are the main field where these technologies are applied, but in other fields such as in archaeology, these technologies can offer many advantages. Ruins reconstruction, ancient life simulation, highly detailed 3D models visualisation of valuable objects from the past or even user free movement in missing places are just some examples found in literature. This paper reviews the latest visualisation technologies and their applicability to the rock art field. The main purpose is to disseminate rock art paintings through AR and VR applications. After the image-based three-dimensional (3D) modelling is obtained, an interactive visit to a shelter for displaying rock art paintings is presented. This is one of examples developed in this paper that pretends to apply the revised AR and VR techniques. In addition, an example of AR is developed that can be easily adapted to further applications displaying rock art paintings.[ES] El uso de las tecnologías de realidad virtual (RV) y realidad aumentada (RA) comenzó a crecer con la aparición de los teléfonos inteligentes. Hasta entonces, había pocos dispositivos portátiles capaces de incorporar estas tecnologías. Principalmente estas tecnologías se aplican en la creación de videojuegos, aunque en otros campos como la arqueología, estas tecnologías tienen mucho que ofrecer. Con estas tecnologías es posible mostrar la reconstrucción de ruinas, la simulación de otra época, modelos 3D altamente detallados de objetos de valor del pasado o incluso trasladar al usuario a lugares que ya no existen. Este trabajo presenta una revisión de las últimas tecnologías de visualización y su aplicabilidad en el campo del arte rupestre, con el objetivo de divulgar las pinturas rupestres a través de aplicaciones de RA y RV. Después del modelado 3D basado en imágenes, se presenta una visita interactiva a un refugio para la visualización de las pinturas rupestres. Este es uno de los ejemplos desarrollados en este trabajo que pretende aplicar las técnicas revisadas de RA y RV. Además, se detalla un sencillo ejemplo de RA que puede fácilmente adaptarse a otras aplicaciones que muestren pinturas rupestres.Blanco Pons, S.; Carrión Ruiz, B.; Lerma, JL. (2016). REVIEW OF AUGMENTED REALITY AND VIRTUAL REALITY TECHNIQUES IN ROCK ART. En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 176-183. https://doi.org/10.4995/arqueologica8.2016.3561OCS17618

ÁNALISIS DE IMAGEN DIGITAL DE LA REGIÓN VISIBLE MEDIANTE SIMULACIÓN DE PINTURAS DE ARTE RUPESTRE

[EN] Non-destructive rock art recording techniques are getting special attention in the last years, opening new research lines in order to improve the level of documentation and understanding of our rich legacy. This paper applies the principal component analysis (PCA) technique in images that include wavelengths between 400-700 nm (visible range). Our approach is focused on determining the difference provided by the image processing of the visible region through four spectral images versus an image that encompasses the entire visible spectrum. The images were taken by means of optical filters that take specific wavelengths and exclude parts of the spectrum. Simulation of rock art is prepared in laboratory. For this purpose, three different pigments were made simulating the material composition of rock art paintings. The advantages of studying the visible spectrum in separate images are analysed. In addition, PCA is applied to each of the images to reduce redundant data. Finally, PCA is applied to the image that contains the entire visible spectrum and is compared with previous results. Through the results of the four visible spectral images one can begin to draw conclusions about constituent painting materials without using decorrelation techniques.[ES] Las técnicas documentación no destructivas de arte rupestre están recibiendo especial atención en los últimos años, abriendo nuevas líneas de investigación para la mejora del nivel de documentación y comprensión de nuestro patrimonio. Este artículo aplica la técnica de análisis de componentes principales (ACP) en imágenes de longitudes de onda entre 400-700 nm (rango visible). Nuestro enfoque se centra en determinar las diferencias proporcionadas por el procesamiento de imágenes de la región del visible a través de cuatro imágenes espectrales y una imagen que abarca el espectro visible completo. Las imágenes se tomaron con filtros ópticos que recogen longitudes de onda determinadas y excluyen parte del espectro.Se preparó una simulación de pigmentos de arte ruprestre en laboratorio. Para ello se hicieron tres tipos de pigmentos diferentes simulando la composición del material de las pinturas rupestres. Se analizaron las ventajas de estudiar el espectro visible en imágenes separadas. Además, se aplicó ACP a cada una de las imágenes para reducir la información redundante. Finalmente, se realizó ACP a la imagen que abarca todo el espectro visible y se comparó con los resultados anteriores. A través de los resultados de las cuatro imágenes espectrales del visible se pueden sacar conclusiones sobre los materiales que constituyen la pintura sin aplicar técnicas de decorrelación.Carrión-Ruiz, B.; Blanco-Pons, S.; Lerma García, JL. (2016). DIGITAL IMAGE ANALYSIS OF THE VISIBLE REGION THROUGH SIMULATION OF ROCK ART PAINTINGS. En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 169-175. https://doi.org/10.4995/arqueologica8.2016.3560OCS16917

Automatic real-time monitoring and assessment of tremor parameters in the upper limb from orientation data

Upper limb tremor is the most prevalent movement disorder and, unfortunately, it is not effectively managed in a large proportion of the patients. Neuroprostheses that stimulate the sensorimotor pathways are one of the most promising alternatives although they are still under development. To enrich the interpretation of data recorded during long-term tremor monitoring and to increase the intelligence of tremor suppression neuroprostheses we need to be aware of the context. Context awareness is a major challenge for neuroprostheses and would allow these devices to react more quickly and appropriately to the changing demands of the user and/or task. Traditionally kinematic features are used to extract context information, with most recently the use of joint angles as highly potential features. In this paper we present two algorithms that enable the robust extraction of joint angle and related features to enable long-term continuous monitoring of tremor with context awareness. First, we describe a novel relative sensor placement identification technique based on orientation data. We focus on relative rather than absolute sensor location, because in many medical applications magnetic and inertial measurement units (MIMU) are used in a chain stretching over adjacent segments, or are always placed on a fixed set of locations. Subsequently we demonstrate how tremor parameters can be extracted from orientation data using an adaptive estimation algorithm. Relative sensor location was detected with an accuracy of 94.12% for the 4 MIMU configuration, and 100% for the 3 MIMU configurations. Kinematic tracking error values with an average deviation of 8% demonstrate our ability to estimate tremor from orientation data. The methods presented in this study constitute an important step toward more user-friendly and context-aware neuroprostheses for tremor suppression and monitoring. © 2014 Lambrecht, Gallego, Rocon and Pons.This work has been funded by the European project NeuroTremor(ICT-2011.5.1-287739)andt he Spanish Consolider project HYPER (CSD2009-00067).Peer Reviewe

Design and implementation of an augmented reality application for rock art visualization in Cova dels Cavalls (Spain)

[EN] Prehistoric rock art paintings, specifically rock-shelters exposed to environmental and anthropogenic factors, are usually faint and severely damaged, being them difficult to identify and understand by visitors. Augmented Reality (AR) supplements reality with virtual information superimposed onto the real world. This sensor-based technology in smartphones/tablets can improve the paintings experience displaying the 2D digital tracings overlapped onto the real scene (rock with faint paintings). This paper presents an AR application (app) developed in Cova dels Cavalls that shows a recreation of a possible original composition full of motifs with descriptive information to improve current guided tour user experiences. This case study aims to evaluate the rock art AR app targeting non-expert visitors as a means of improving rock art knowledge and sensibility of a fragile archaeological UNESCO Work Heritage site. To achieve this, a variety of participants with different backgrounds and interests tested the AR app on site and answered a complete questionnaire about the use of AR mobile apps. Overall, the results showed great acceptance of this AR app, mainly because in addition to adding new information interactively, it helps to identify the rock art motifs, as well as to recognise them quickly, improving their understanding.The authors gratefully acknowledge the support from the Spanish Ministerio de Economia y Competitividad to the project HAR201459873-R. The authors acknowledge the authorisation of the Conselleria d'Educacio, Investigacio, Cultura i Esports the chance to carry out research at this exceptional archaeological site.Blanco-Pons, S.; Carrión-Ruiz, B.; Lerma, JL.; Villaverde, V. (2019). Design and implementation of an augmented reality application for rock art visualization in Cova dels Cavalls (Spain). Journal of Cultural Heritage. 39:177-185. https://doi.org/10.1016/j.culher.2019.03.014S1771853

Modelización del estator de un motor piezoeléctrico de onda viajera: una revision integrada y nueva perspectiva

[EN] Articles from different areas which are closely related to the modelling of the stator of travelling wave ultrasonic motors (TWUMs) are reviewed in this work. Thus, important issues relevant to this problem are identified from the areas of vibration of annular plates, laminated plate theories, and modelling of piezoelectric transducers. From this integrated point of view, it becomes clear that there are some very important issues yet to be addressed in the modelling of TWUMs. Firstly, the influence of material properties and stator dimensions on output efficiency, electromechanical coupling coefficients (EMCC) and maximum output energy is to be investigated in more detail. Secondly, the modelling of the electric potential field (by explicitly including the charge equation) for TWUMs seems to be a must for better prediction of displacements and electric fields close to the resonance, as suggested by some recent works [1]. Moreover, the improvement of current models by using shear deformation (or higher order) laminated plate theories (LPTs) in conjunction with approximated methods of solution are discussed. In addition to analytical models, those works using Finite Element and Finite difference Methods (FEM and FDM) for the modelling and simulation of the TWUM stator dynamics are reviewed.[ES] En este trabajo se realiza una revisión de los trabajos de investigación realizados en diversas áreas sobre el modelado del estátor de los motores ultrasónicos de onda viajera (TWUMs). Entre los problemas relevantes que se han estudiado podemos citar la vibración de placas anulares, las teorías de placas laminadas y el modelado de transductores piezoeléctricos. A raíz de este punto de vista integral se hace manifiesto que todavía quedan asuntos importantes que estudiar en el modelado de los TWUMs. En primer lugar, la influencia de las propiedades del material y las dimensiones del estátor en la eficiencia del motor, los coeficientes de acoplamiento electromecánico (EMCC) y la máxima energía entregada deberían ser estudiados más detenidamente. En segundo lugar, el modelado de la distribución del campo eléctrico en los TWUMs (incluyendo la ecuación de carga explícitamente) parece imprescindible para lograr una predicción mejor del desplazamiento y del campo eléctrico cerca de la resonancia, como se ha apuntado en referencias actuales [1]. Además, se discute las mejoras que incorporaría a los modelos existentes en la actualidad la inclusión de las teorías de placas laminadas (LPTs) con deformaciones de corte (o de orden superior), resueltas mediante métodos aproximados. Como complemento a los modelos analíticos, se realiza asimismo una revisión de las técnicas de elementos finitos (FEM) y diferencias finitas (FDM) empleadas en la simulación de la dinámica del estátor de los motores TWUM.The authors are thankful for the support from the National Science and Research Office (Senacyt), the Institute for Human Resource Development and Proficiency (IFARHU), both of Panama, and the European Union for its support through grant DE-4205.Peer reviewe