2,754 research outputs found
Aplicación terapéutica de las células troncales adultas y embrionarias. ¿Mito o realidad?
Therapeutic application of the main adult and embryonic cells. Myth or reality?Aplicación terapéutica de las células troncales adultas y embrionarias. ¿Mito o realidad
A Topologically Consistent Color Digital Image Representation by a Single Tree
A novel, flexible (non-unique) and topologically consistent
representation called CRIT (Contour-Region incidence Tree) for a color
2D digital image I is defined here. The CRIT is a tree containing all the
inter and intra connectivity information of the constant-color regions.
Considering I as an abstract cell complex (ACC), its topological infor mation can be packed as a smaller (in terms of cells) ACC, whose 2-cells
are the different constant-color regions of I. This modus operandi over comes the classical connectivity paradoxes of digital images by working
with lower-dimensional cells such as 0-cells, 1-cells, and 2-cells. The CRIT
structure allows to describe this smaller ACC in a non-redundant way.
The proposed technique is based on the previous construction of the
Homological Spanning Forest (HSF) structures for encoding homological
information of the ACCs canonically associated to I, in terms of rooted
trees connecting digital object elements without redundancyMinisterio de Ciencia e Innovación PID2019-110455GB-I00 (Par-HoT
Caso clÃnico: Insuficiencia Respiratoria Aguda en el Postoperatorio de una Cesárea Urgente
Paciente de 31 años de edad, gestante gemelar mediante FIV con feto muerto a la 21 semana. Sin antecedentes personales ni familiares, no consumo de fármacos, no hábitos tóxicos, sin alergias medicamentosas conocidas. ASA I.
Ingresa por amenaza de parto prematuro, realizándosele cesárea urgente por situación transversa del feto. Intraoperatorio sin incidentes. Recién nacido prematuro.
Al segundo dÃa del postoperatorio comienza con cuadro de abdomen agudo compatible con Ãleo paralÃtico, que empeora al dÃa siguiente precisando laparotomÃa exploradora. Se aprecia peritonitis secundaria a endometritis. Se realizan lavados de cavidad abdominal y se instaura tratamiento antibiótico.
Ingresa en la Unidad de Reanimación extubada, consciente, orientada, hemodinámicamente estable con bajas dosis de vasoactivos, y con función respiratoria y renal conservada. Evolución ligeramente favorable en los dÃas posteriores permitiendo retirar vasoactivos; auscultación cardio-respiratoria normal; radiografÃa de tórax con pinzamiento del ángulo costodiafragmático izquierdo, sin otros hallazgos. Sin embargo, la paciente presenta una discreta taquicardia (100-105 lpm), abdomen distendido, doloroso y sin peristaltismo, leucocitosis (entorno a los 11.000 x 109 L-1) y hemoglobina de 9 mg dl-1 (resto de la analÃtica compatible con la normalidad).
En el tercer dÃa de estancia en la Unidad presenta un importante deterioro del estado general, con clÃnica de insuficiencia respiratoria aguda severa (disnea, taquipnea, uso de la musculatura accesoria, descoordinación tóraco-abdominal, obnubilación), reagudización del dolor abdominal con distensión, fiebre de 38,5ºC y descenso de la hemoglobina de un punto sin sangrado aparente por drenajes
SORA Methodology for Multi-UAS Airframe Inspections in an Airport
Deploying Unmanned Aircraft Systems (UAS) in safety- and business-critical operations
requires demonstrating compliance with applicable regulations and a comprehensive understanding
of the residual risk associated with the UAS operation. To support these activities and enable the
safe deployment of UAS into civil airspace, the European Union Aviation Safety Agency (EASA) has
established a UAS regulatory framework that mandates the execution of safety risk assessment for
UAS operations in order to gain authorization to carry out certain types of operations. Driven by
this framework, the Joint Authorities for Rulemaking on Unmanned Systems (JARUS) released the
Specific Operation Risk Assessment (SORA) methodology that guides the systematic risk assessment
for UAS operations. However, existing work on SORA and its applications focuses mainly on single
UAS operations, offering limited support for assuring operations conducted with multiple UAS and
with autonomous features. Therefore, the work presented in this paper analyzes the application of
SORA for a Multi-UAS airframe inspection (AFI) operation, that involves deploying multiple UAS
with autonomous features inside an airport. We present the decision-making process of each SORA
step and its application to a multiple UAS scenario. The results shows that the procedures and safety
features included in the Multi-AFI operation such as workspace segmentation, the independent
multi-UAS AFI crew proposed, and the mitigation actions provide confidence that the operation can
be conducted safely and can receive a positive evaluation from the competent authorities. We also
present our key findings from the application of SORA and discuss how it can be extended to better
support multi-UAS operations.Unión Europea 10101725
Time measurement characterization of stand-to-sit and sit-to-stand transitions by using a smartphone
The aim of this study is to analyze a common method to measure the acceleration of a daily activity pattern by using a smartphone. In this sense, a numerical approach is proposed to transform the relative acceleration signal, recorded by a triaxial accelerometer, into an acceleration referred to an inertial reference. The integration of this acceleration allows to determine the velocity and position with respect to an inertial reference. Two different kinematic parameters are suggested to characterize the profile of the velocity during the sit-to-stand and stand-to-sit transitions for Parkinson and control subjects. The results show that a dimensionless kinematic parameter, which is linked to the time of sit-to-stand and stand-to-sit transitions, has the potential to differentiate between Parkinson and control subjects.Peer ReviewedPreprin
Desarrollo de un entorno de aprendizaje virtual aplicado a la búsqueda y gestión de información
Desarrollo de un prototipo de entorno virtual de aprendizaje orientado a la formación de estudiantes universitarios en las competencias informacionales relacionadas con la búsqueda y gestión de la información
Parallel Image Processing Using a Pure Topological Framework
Image processing is a fundamental operation
in many real time applications, where lots of parallelism
can be extracted. Segmenting the image into different
connected components is the most known operations, but
there are many others like extracting the region adjacency
graph (RAG) of these regions, or searching for features
points, being invariant to rotations, scales, brilliant
changes, etc. Most of these algorithms part from the basis
of Tracing-type approaches or scan/raster methods. This
fact necessarily implies a data dependence between the
processing of one pixel and the previous one, which
prevents using a pure parallel approach. In terms of time
complexity, this means that linear order O(N) (N being the
number of pixels) cannot be cut down. In this paper, we
describe a novel approach based on the building of a pure
Topological framework, which allows to implement fully
parallel algorithms. Concerning topological analysis, a first
stage is computed in parallel for every pixel, thus
conveying the local neighboring conditions. Then, they are
extended in a second parallel stage to the necessary global
relations (e.g. to join all the pixels of a connected
component). This combinatorial optimization process can
be seen as the compression of the whole image to just one
pixel. Using this final representation, every region can be
related with the rest, which yields to pure topological
construction of other image operations. Besides, complex
data structures can be avoided: all the processing can be
done using matrixes (with the same indexation as the
original image) and element-wise operations. The time
complexity order of our topological approach for a m×n
pixel image is near O(log(m+n)), under the assumption that
a processing element exists for each pixel. Results for a
multicore processor show very good scalability until the
memory bandwidth bottleneck is reached, both for bigger
images and for much optimized implementations. The
inherent parallelism of our approach points to the
direction that even better results will be obtained in other
less classical computing architectures.1Ministerio de EconomÃa y Competitividad (España) TEC2012-37868-C04-02AEI/FEDER (UE) MTM2016-81030-PVPPI of the University of Sevill
On the Topological Disparity Characterization of Square-Pixel Binary Image Data by a Labeled Bipartite Graph
Given an nD digital image I based on cubical n-xel, to fully
characterize the degree of internal topological dissimilarity existing in I
when using different adjacency relations (mainly, comparing 2n or 2n −1
adjacency relations) is a relevant issue in current problems of digital
image processing relative to shape detection or identification. In this
paper, we design and implement a new self-dual representation for a
binary 2D image I, called {4, 8}-region adjacency forest of I ({4, 8}-RAF,
for short), that allows a thorough analysis of the differences between the
topology of the 4-regions and that of the 8-regions of I. This model can
be straightforwardly obtained from the classical region adjacency tree
of I and its binary complement image Ic, by a suitable region label
identification. With these two labeled rooted trees, it is possible: (a) to
compute Euler number of the set of foreground (resp. background) pixels
with regard to 4-adjacency or 8-adjacency; (b) to identify new local and
global measures and descriptors of topological dissimilarity not only for
one image but also between two or more images. The parallelization of
the algorithms to extract and manipulate these structures is complete,
thus producing efficient and unsophisticated codes with a theoretical
computing time near the logarithm of the width plus the height of an
image. Some toy examples serve to explain the representation and some
experiments with gray real images shows the influence of the topological
dissimilarity when detecting feature regions, like those returned by the
MSER (maximally stable extremal regions) method.Ministerio de EconomÃa, Industria y Competitividad PID2019-110455GB-I00 (Par-HoT)Junta de AndalucÃa US-138107
Building Hierarchical Tree Representations Using Homological-Based Tools
A new algorithm for computing the α-tree hierarchical repre sentation of a grey-scale digital image is presented here. The technique is
based on an efficient simplified version of the Homological Spanning For est (HSF) for encoding homological and homotopy-based information
of binary digital images. We create one Adjacency Tree (AdjT) for each
intensity contrast in a fully parallel manner. These trees, which define a
Contrast Adjacency Forest (CAdjF), are in turn transversely intercon nected by another couple of trees: the classical α-tree, and a new one
complementing it, called here the α∗-tree. They convey the information
of the contours and the flat regions of the original color image, plus the
relations between them. Using both the α and α∗-trees, this new topolog ical representation prevents some classical drawbacks that appear when
working with a single tree. An implementation in OCTAVE/MATLAB
validates the correctness of our algorithm.Ministerio de Ciencia e Innovación PID2019-110455GB-I00 (Par-HoT
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