La función activadora de un apósito bioactivo con carga iónica sobre los fibroblastos humanos

La cicatrización de las heridas es un proceso complejo que implica diferentes fases que se solapan entre sí, incluyendo la inflamación, la epitelización, la angiognesis y la síntesis y deposición de matriz extracelular. Los fibroblastos dérmicos tienen una función esencial en la formación del tejido de granulación. Migran hasta la lesión en respuesta a citoquinas, proliferan y sintetizan las proteínas de la matriz extracelular, las cuales son la base del proceso de reparación futuro. Los oligoelementos tales como el zinc y el manganeso son necesarios para muchas funciones celulares y, por consiguiente, pueden potencialmente estimular los procesos de reparación de las heridas. En el presente estudio hemos investigado el efecto de un aposito que contiene zinc, calcio y manganeso (Trionic®) sobre la proliferación, el crecimiento, la síntesis de colágeno I y III y la migración de los fibroblastos. Los resultados obtenidos indican que los oligoelementos solubles presentes en Trionic® actúan estimulando la proliferación, el crecimiento, la biosíntesis de colágeno y la migración de los fibroblastos. Dada la participación crucial que estas funciones celulares tienen sobre el comportamiento de los fibroblastos durante el proceso de formación del tejido de granulación, concluimos que los iones Ca2+, Zn2+, y Mn2+ contenidos en Trionic® pueden proporcionar potenciales beneficios en el tratamiento de las heridas crónicas y durante la fase reparativa del proceso de cicatrización.

Comparison of acute non-visual bright light responses in patients with optic nerve disease, glaucoma and healthy controls.

This study examined the effect of optic nerve disease, hence retinal ganglion cell loss, on non-visual functions related to melanopsin signalling. Test subjects were patients with bilateral visual loss and optic atrophy from either hereditary optic neuropathy (n = 11) or glaucoma (n = 11). We measured melatonin suppression, subjective sleepiness and cognitive functions in response to bright light exposure in the evening. We also quantified the post-illumination pupil response to a blue light stimulus. All results were compared to age-matched controls (n = 22). Both groups of patients showed similar melatonin suppression when compared to their controls. Greater melatonin suppression was intra-individually correlated to larger post-illumination pupil response in patients and controls. Only the glaucoma patients demonstrated a relative attenuation of their pupil response. In addition, they were sleepier with slower reaction times during nocturnal light exposure. In conclusion, glaucomatous, but not hereditary, optic neuropathy is associated with reduced acute light effects. At mild to moderate stages of disease, this is detected only in the pupil function and not in responses conveyed via the retinohypothalamic tract such as melatonin suppression.

Visual performance in preterm infants with brain injuries compared with low-risk preterm infants

Background: Neonatal brain injuries are the main cause of visual deficit produced by damage to posterior visual pathways.While there are several studies of visual function in low-risk preterm infants or older children with brain injuries, research in children of early age is lacking. Aim: To assess several aspects of visual function in preterm infants with brain injuries and to compare them with another group of low-risk preterm infants of the same age. Study design and subjects: Forty-eight preterm infants with brain injuries and 56 low-risk preterm infants. Outcome measures: The ML Leonhardt Battery of Optotypes was used to assess visual functions. This test was previously validated at a post-menstrual age of 40 weeks in newborns and at 30-plus weeks in preterm infants. Results: The group of preterminfants with brain lesions showed a delayed pattern of visual functions in alertness, fixation, visual attention and tracking behavior compared to infants in the healthy preterm group. The differences between both groups, in the visual behaviors analyzed were around 30%. These visual functions could be identified from the first weeks of life. Conclusion: Our results confirm the importance of using a straightforward screening test with preterminfants in order to assess altered visual function, especially in infants with brain injuries. The findings also highlight the need to provide visual stimulation very early on in life.

Spinal cord injury affects the interplay between visual and sensorimotor representations of the body.

The brain integrates multiple sensory inputs, including somatosensory and visual inputs, to produce a representation of the body. Spinal cord injury (SCI) interrupts the communication between brain and body and the effects of this deafferentation on body representation are poorly understood. We investigated whether the relative weight of somatosensory and visual frames of reference for body representation is altered in individuals with incomplete or complete SCI (affecting lower limbs' somatosensation), with respect to controls. To study the influence of afferent somatosensory information on body representation, participants verbally judged the laterality of rotated images of feet, hands, and whole-bodies (mental rotation task) in two different postures (participants' body parts were hidden from view). We found that (i) complete SCI disrupts the influence of postural changes on the representation of the deafferented body parts (feet, but not hands) and (ii) regardless of posture, whole-body representation progressively deteriorates proportionally to SCI completeness. These results demonstrate that the cortical representation of the body is dynamic, responsive, and adaptable to contingent conditions, in that the role of somatosensation is altered and partially compensated with a change in the relative weight of somatosensory versus visual bodily representations.

¿Pueden contribuir los métodos visuales a avanzar hacia una investigación inclusiva? Un estudio sobre inclusión sociolaboral con personas con Trastorno Mental Grave (TMG) = Can visual methods help to go forward inclusive research? A study about social and labor inclusion with people with Severe Mental Illness (SMI)

En este artículo se pretende mostrar cómo la utilización de métodos visuales en la investigación contribuye a potenciar la participación activa de las personas con TMG. Se utiliza como ejemplo un estudio de caso de corte cualitativo que incorpora tres actividades de componente visual (el dibujo “el río de la vida”, las fotografías y el dibujo de proyección de futuro) para favorecer la reflexión narrada que, sobre sus experiencias y vivencias, desarrollan cinco personas con TMG. El uso de las fotografías y dibujos en este estudio permite afirmar que estas estrategias se han mostrado válidas para acceder, en la medida que los participantes han querido, a esferas de vida personales en trayectorias vitales determinadas por la enfermedad mental

Accessing forgotten memory traces from long-term memory via visual movements

Because memory retrieval often requires overt responses, it is difficult to determine to what extend forgetting occurs as a problem in explicit accessing of long-term memory traces. In this study, we used eye-tracking measures in combination with a behavioural task that favoured high forgetting rates to investigate the existence of memory traces from long-term memory in spite of failure in accessing them consciously. In 2 experiments, participants were encouraged to encode a large set of sound-picture56 location associations. In a later test, sounds were presented and participants were instructed to visually scan, before a verbal memory report, for the correct location of the associated pictures in an empty screen. We found the reactivation of associated memories by sound cues at test biased oculomotor behaviour towards locations congruent with memory representations, even when participants failed to consciously provide a memory report of it. These findings reveal the emergence of a memory-guided behaviour that can be used to map internal representations of forgotten memories from long-term memory.

L’art visual en els moviments pedagògics del segle XX: la concreció de l’educació artística en els llibres escolars

Les tradicions escolars d’educació artística s’han construït des de la transmissió oral i escrita de projectes i programes. Tanmateix, la concreció de les propostes legislatives, ideacionals i teòriques s’ha expressat, fonamentalment, a través dels documents. Tant és així que, per exemple, la cultura escolar a l’entorn de l’educació artística s’ha anat conformant des dels projectes codificats en els llibres per a mestres i per a infants. Per aquest motiu en aquest article es proposa una aproximació a aquests llibres a fi de conèixer quines són les característiques dels discursos de l’aprenentatge artístic que s’han consolidat al llarg del segle XX en el nostre entorn; aproximació que s’assaja a partir d’encreuar les petjades que han deixat els llibres escolars amb la seva imbricació o, fins i tot, negació amb les tendències de la pedagogia contemporània.

La memoria visual de la escuela

El artículo versa sobre la memoria visual de la escuela incidiendo tanto en las motivaciones que orientan la producción de imágenes como sobre el acercamiento a ellas que hoy podemos realizar. Parte así del análisis de los motivos de producción de imágenes según los períodos de la evolución escolar, prosigue una reseña de las distintas posibilidades de formación de memoria a través de las representaciones gráficas de la escuela y, finalmente, se plantean las principales características así como retos del tratamiento museológico y museográfico de la imagen escolar. El objetivo del artículo es, por lo tanto, realizar una aproximación a las imágenes concibiéndolas como bienes gráficos que requieren un avance en las formas de conservación, difusión e investigación que están desarrollando los centros de gestión del patrimonio educativo.

Development and validation of a visual grading scale for assessing image quality of AP pelvis radiographic images.

OBJECTIVE: The aim of this article was to apply psychometric theory to develop and validate a visual grading scale for assessing the visual perception of digital image quality anteroposterior (AP) pelvis. METHODS: Psychometric theory was used to guide scale development. Seven phantom and seven cadaver images of visually and objectively predetermined quality were used to help assess scale reliability and validity. 151 volunteers scored phantom images, and 184 volunteers scored cadaver images. Factor analysis and Cronbach's alpha were used to assess scale validity and reliability. RESULTS: A 24-item scale was produced. Aggregated mean volunteer scores for each image correlated with the rank order of the visually and objectively predetermined image qualities. Scale items had good interitem correlation (≥0.2) and high factor loadings (≥0.3). Cronbach's alpha (reliability) revealed that the scale has acceptable levels of internal reliability for both phantom and cadaver images (α = 0.8 and 0.9, respectively). Factor analysis suggested that the scale is multidimensional (assessing multiple quality themes). CONCLUSION: This study represents the first full development and validation of a visual image quality scale using psychometric theory. It is likely that this scale will have clinical, training and research applications. ADVANCES IN KNOWLEDGE: This article presents data to create and validate visual grading scales for radiographic examinations. The visual grading scale, for AP pelvis examinations, can act as a validated tool for future research, teaching and clinical evaluations of image quality.

Timing of visual stimuli in V1 and V5/MT: fMRI and TMS

Time perception is used in our day-to-day activities. While we understand quite well how our brain processes vision, touch or taste, brain mechanisms subserving time perception remain largely understudied. In this study, we extended an experiment of previous master thesis run by Tatiana Kenel-Pierre. We focused on time perception in the range of milliseconds. Previous studies have demonstrated the involvement of visual areas V1 and V5/MT in the encoding of temporal information of visual stimuli. Based on these previous findings the aim of the present study was to understand if temporal information was encoded in V1 and extrastriate area V5/MT in different spatial frames i.e., head- centered versus eye-centered. To this purpose we asked eleven healthy volunteers to perform a temporal discrimination task of visual stimuli. Stimuli were presented at 4 different spatial positions (i.e., different combinations of retinotopic and spatiotopic position). While participants were engaged in this task we interfered with the activity of the right dorsal V1 and the right V5/MT with transcranial magnetic stimulation (TMS). Our preliminary results showed that TMS over both V1 and V5/MT impaired temporal discrimination of visual stimuli presented at specific spatial coordinates. But whereas TMS over V1 impaired temporal discrimination of stimuli presented in the lower left quadrant, TMS over V5/MT affected temporal discrimination of stimuli presented at the top left quadrant. Although it is always difficult to draw conclusions from preliminary results, we could tentatively say that our data seem to suggest that both V1 and V5/MT encode visual temporal information in specific spatial frames.

Análisis económico de una función cuadrática de gastos de producción con coeficientes borrosos

En el ámbito de la Economía de la Empresa tiene mucha importancia el estudio de los gastos de producción E(Q) que se originarán en el proceso y que generalmente vendrán expresados matemáticamente por una dependencia lineal o cuadrática de las unidades Q que se proponen fabricar. Supondremos, además, que esta función está afectada por dos restricciones: una es de productividad, Q1 ≤ Q2 ≤ Q3 , y otra de limitación de gastos máximos permitidos, E(Q) ≤ EM . En el presente artículo partiremos de una función cuadrática nítida, en la cual justificaremos el signo de los coeficientes que hemos empleado. Después, para adentrarnos en el campo fuzzy, la generalizaremos con otra de coeficientes borrosos. Naturalmente, la nueva función borrosa ya no se expresará a través de una única curva, sino que estará constituida por un haz infinito de curvas nítidas, cada una de ellas con un determinado grado de posibilidad. Centramos nuestra atención en las curvas que llamamos central, inferior y superior. El núcleo de nuestro análisis consistirá básicamente en reducir paulatinamente los soportes de los coeficientes hasta hallar un cierto valor k del α-corte, de manera que a partir de él todas las curvas del haz borroso tengan sentido económico y cumplan las dos restricciones impuestas. En último lugar, y a través de un caso numérico, comprobaremos las deducciones teóricas que hemos obtenido en el análisis anterior

Visual SLAM for 3D large-scale seabed acquisition employing underwater vehicles

This paper presents a novel technique to align partial 3D reconstructions of the seabed acquired by a stereo camera mounted on an autonomous underwater vehicle. Vehicle localization and seabed mapping is performed simultaneously by means of an Extended Kalman Filter. Passive landmarks are detected on the images and characterized considering 2D and 3D features. Landmarks are re-observed while the robot is navigating and data association becomes easier but robust. Once the survey is completed, vehicle trajectory is smoothed by a Rauch-Tung-Striebel filter obtaining an even better alignment of the 3D views and yet a large-scale acquisition of the seabed

Visual SLAM for underwater vehicles using video velocity log and natural landmarks

A visual SLAM system has been implemented and optimised for real-time deployment on an AUV equipped with calibrated stereo cameras. The system incorporates a novel approach to landmark description in which landmarks are local sub maps that consist of a cloud of 3D points and their associated SIFT/SURF descriptors. Landmarks are also sparsely distributed which simplifies and accelerates data association and map updates. In addition to landmark-based localisation the system utilises visual odometry to estimate the pose of the vehicle in 6 degrees of freedom by identifying temporal matches between consecutive local sub maps and computing the motion. Both the extended Kalman filter and unscented Kalman filter have been considered for filtering the observations. The output of the filter is also smoothed using the Rauch-Tung-Striebel (RTS) method to obtain a better alignment of the sequence of local sub maps and to deliver a large-scale 3D acquisition of the surveyed area. Synthetic experiments have been performed using a simulation environment in which ray tracing is used to generate synthetic images for the stereo system

Afrontamiento de situaciones de hostilidad y desempeño de la función directiva. Planteamientos y reflexiones a raíz de una actividad de formación permanente de directivos de centros educativos de titularidad pública

The intervention in the organized conflicts and, particularly, the confrontation of hostile situations (based on the emotional alteration, the strain, the verbal aggressiveness, etc) is one of the aspects that worry the principals of the educative centres and, therefore, a main attention must be given to the initial and permanent training to have managing duties. Throughout the text we take some aspects into account in the development of these managing skills:a) we set the distinctive features; b) we answer to the dilemma about the existence of improvement possibilities; c) we state the need to star from the motivation and the active participation of the principals in their own personal development and, finally, d) we contribute with the design of a training activity to develop skills to confront hostile situations, addressed to the principals of primary and secondary schools, that was done in Girona, in November 2005