403 research outputs found
Crack-Depth Prediction in Steel Based on Cooling Rate
One criterion for the evaluation of surface cracks in steel welds is to analyze the depth of the crack, because it is an effective indicator of its potential risk. This paper proposes a new methodology to obtain an accurate crack-depth prediction model based on the combination of infrared thermography and the 3D reconstruction procedure. In order to do this, a study of the cooling rate of the steel is implemented through active infrared thermography, allowing the study of the differential thermal behavior of the steel in the fissured zone with respect to the nonfissured zone. These cooling rate data are correlated with the real geometry of the crack, which is obtained with the 3D reconstruction of the welds through a macrophotogrammetric procedure. In this way, it is possible to analyze the correlation between cooling rate and depth through the different zones of the crack. The results of the study allow the establishment of an accurate predictive depth model which enables the study of the depth of the crack using only the cooling rate data. In this way, the remote measure of the depth of the surface steel crack based on thermography is possible
Novel types of anti-ecloud surfaces
In high power RF devices for space, secondary electron emission appears as
the main parameter governing the multipactor effect and as well as the e-cloud
in large accelerators. Critical experimental activities included development of
coatings with low secondary electron emission yield (SEY) for steel (large
accelerators) and aluminium (space applications). Coatings with surface
roughness of high aspect ratio producing the so-call secondary emission
suppression effect appear as the selected strategy. In this work a detailed
study of the SEY of these technological coatings and also the experimental
deposition methods (PVD and electrochemical) are presented. The coating-design
approach selected for new low SEY coatings include rough metals (Ag, Au, Al),
rough alloys (NEG), particulated and magnetized surfaces, and also graphene
like coatings. It was found that surface roughness also mitigate the SEY
deterioration due to aging processes.Comment: 4 pages, contribution to the Joint INFN-CERN-EuCARD-AccNet Workshop
on Electron-Cloud Effects: ECLOUD'12; 5-9 Jun 2012, La Biodola, Isola d'Elba,
Italy; CERN Yellow Report CERN-2013-002, pp.153-15
A comparative study between wmms and tls for the stability analysis of the San Pedro church barrel vault by means of the finite element method
Stability of masonry constructions is highly conditioned by the geometric disposition of its elements due to its low tensile strength and great compressive mechanical properties. Under this framework, this paper attempts to evaluate the suitability of a wearable mobile mapping solution, equipped in a backpack and based on the well-known simultaneous location and mapping paradigm, for the structural diagnosis of historical constructions. To evaluate the suitability of this device, the structural analysis obtained is compared with a high precision terrestrial laser scanner, which is considered as ground truth. The Romanesque church of San Pedro (Becerril del Carpio, Spain) was selected as a study case. This construction, initially conceived in the XIIIth century, has experimented in the past a soil settlement promoting the leaning of the north wall, several plastic hinges in its barrel vault and a visible geometrical deformation. The comparison of both techniques was carried out at different levels: i) an evaluation of the time needed to obtain the point cloud of the church; ii) an accuracy assessment based on the comparison of a terrestrial network using artificial spheres as checkpoints and; iii) an evaluation of the discrepancies, in terms of safety factor and collapse topology, found during the advance numerical evaluation of the barrel vault by means of the finite element method. This comparison places this wearable mobile mapping solution as an interesting tool for the creation of advanced numerical simulations to evaluate the structural stability of historical constructionsJunta de Castilla y León | Ref. SA075P17FEDER | Ref. SOE1/P5/P025
DEVELOPMENT OF AN ALL-PURPOSE FREE PHOTOGRAMMETRIC TOOL
Photogrammetry is currently facing some challenges and changes mainly related to automation, ubiquitous processing and variety of applications. Within an ISPRS Scientific Initiative a team of researchers from USAL, UCLM, FBK and UNIBO have developed an open photogrammetric tool, called GRAPHOS (inteGRAted PHOtogrammetric Suite). GRAPHOS allows to obtain dense and metric 3D point clouds from terrestrial and UAV images. It encloses robust photogrammetric and computer vision algorithms with the following aims: (i) increase automation, allowing to get dense 3D point clouds through a friendly and easy-to-use interface; (ii) increase flexibility, working with any type of images, scenarios and cameras; (iii) improve quality, guaranteeing high accuracy and resolution; (iv) preserve photogrammetric reliability and repeatability. Last but not least, GRAPHOS has also an educational component reinforced with some didactical explanations about algorithms and their performance. The developments were carried out at different levels: GUI realization, image pre-processing, photogrammetric processing with weight parameters, dataset creation and system evaluation. The paper will present in detail the developments of GRAPHOS with all its photogrammetric components and the evaluation analyses based on various image datasets. GRAPHOS is distributed for free for research and educational needs
A MULTI-DATA SOURCE AND MULTI-SENSOR APPROACH FOR THE 3D RECONSTRUCTION AND VISUALIZATION OF A COMPLEX ARCHAELOGICAL SITE: THE CASE STUDY OF TOLMO DE MINATEDA
Positron Emission Tomography-Computed Tomography and Magnetic Resonance Imaging Assessments in a Mouse Model of Implant-Related Bone and Joint Staphylococcus aureus Infection.
Osteomyelitis is an infection of the bone, associated with an inflammatory process. Imaging plays an important role in establishing the diagnosis and the most appropriate patient management. However, data are lacking regarding the use of preclinical molecular imaging techniques to assess osteomyelitis progression in experimental models. This study aimed to compare structural and molecular imaging to assess disease progression in a mouse model of implant-related bone and joint infections caused by Staphylococcus aureus. In SWISS mice, the right femur was implanted with a resorbable filament impregnated with S. aureus (infected group, n = 10) or sterile culture medium (uninfected group, n = 6). Eight animals (5 infected, 3 uninfected) were analyzed with magnetic resonance imaging (MRI) at 1, 2, and 3 weeks postintervention, and 8 mice were analyzed with [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)-computed tomography (CT) at 48 h and at 1, 2, and 3 weeks postintervention. In infected animals, CT showed bone lesion progression, mainly in the distal epiphysis, although some uninfected animals presented evident bone sequestra at 3 weeks. MRI showed a lesion in the articular area that persisted for 3 weeks in infected animals. This lesion was smaller and less evident in the uninfected group. At 48 h postintervention, FDG-PET showed higher joint uptake in the infected group than in the uninfected group (P = 0.025). Over time, the difference between groups increased. These results indicate that FDG-PET imaging was much more sensitive than MRI and CT for differentiating between infection and inflammation at early stages. FDG-PET clearly distinguished between infection and postsurgical bone healing (in uninfected animals) from 48 h to 3 weeks after implantation. IMPORTANCE Our results encourage future investigations on the utility of the model for testing different therapeutic procedures for osteomyelitis.We thank Yolanda Sierra, Alexandra de Francisco, and María de la Jara Felipe, from the
Imaging Laboratory for Small Animals of the Instituto de Investigación Sanitaria, Gregorio
Marañón, for their excellent work with animal preparation and imaging protocols. Additionally,
we thank Daniel Calle, from the Advanced Imaging Unit of CNIC, for his help in imaging
postprocessing.
This study was partially supported by the Instituto de Salud Carlos III (grants PI20/
01632 and PT20/00044), cofunded by the European Regional Development Fund (ERDF),
A way to make Europe. This work was also supported by the Diagnosis and Treatment
Follow-up of Severe Staphylococcal Infections with Anti-Staphylococcal Antibodies and
Immune-PET project of the Grant Fundación BBVA a Equipos de Investigación Científica
2018, by the Fundación Ramón Areces, and by Comunidad de Madrid (S2022/BMD-7403
RENIM-CM). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de
Ciencia e Innovación (MCIN), and the Pro CNIC Foundation, and it is a Severo Ochoa Center
of Excellence (grant CEX2020-001041-S, funded by MICIN/AEI/10.13039/501100011033).S
TELMA: Entorno de formación personalizada online en Cirugía de Mínima Invasión
TELMA es un entorno de formación y aprendizaje online basado en edición de vídeo laparoscópico, la gestión del conocimiento y el trabajo colaborativo con el fin de mejorar la efectividad y eficacia de los procesos de formación (inicial y continuada) de los cirujanos de Cirugía de Mínima Invasión (CMI). TELMA explota el uso del vídeo laparoscópico como el núcleo de los contenidos didácticos y hace uso de tecnologías de formación online y gestión de contenidos digitales multimedia, para mejorar la adaptación, calidad y eficiencia del servicio ofrecido al usuario. TELMA persigue acortar las curvas de aprendizaje, proporcionando a los cirujanos un acceso ubicuo a contenidos educativos y metodologías didácticas, dotando al aprendizaje de mayor interactividad y proporcionando a los alumnos un papel más activo, una mejor adquisición de los conocimientos y habilidades y un mayor uso de las fuentes de información disponibles
Digitization of Cultural Heritage Buildings for Preventive Conservation Purposes
This work aims at presenting the experimental results obtained by the application
of one of the digital protocols developed during the European project HeritageCare:
Monitoring and preventive conservation of historical and cultural heritage. These protocols
are devoted to the preventive conservation of heritage constructions and its assets. More
specifically, the application of the second level of services of the HeritageCare system is
presented through two complementary case studies: a large Neo-Manueline church situated
nearby Guimarães, Portugal, and a small Romanesque church located in Palencia, Spain. In
each case study a different set of digital technologies was employed with the aim of evaluating
the flexibility of the developed protocols. This set of technologies comprises the use of in-house apps for enhancing the visual inspection together with geomatic techniques based on static and
wearable laser scanners as well as digital single-lens reflex and as-built 360º cameras. The
results obtained by the application of these digital tools have allowed the creation of a Web-
GIS platform for ensuring the proper documentation of cultural heritage and streamlining the
management of their conservation process according to a proactive approach
Dinámica temporal de la disponibilidad de agua y microclima en aguadas del biotopo protegido Dos Lagunas, Petén, Guatemala
En el territorio de la Selva Maya se han identificado a los cuerpos de agua estacionales denominados localmente aguadas, como un recurso crítico para la supervivencia de especies de fauna silvestre, ya que son su principal fuente de agua durante la temporada seca. En el presente estudio se registró en cinco aguadas, la dinámica temporal de la acumulación de agua empleando una cámara automática, así como la temperatura y la humedad relativa utilizando sensores automáticos a lo largo de abril a agosto del 2016. En cuanto a la disponibilidad de agua, esta fue disminuyendo hasta agotarse al final de la temporada seca en el mes de abril, y fue aumentando al inicio de la temporada lluviosa en junio. Para la temporada seca se registró una temperatura promedio (desviación estándar) de 27.65 (4.52)ªC y una humedad relativa de 71.30 (19.00)%, mientras que para la temporada lluviosa la temperatura promedio fue de 26.09 (3.21)ªC y humedad relativa promedio de 86.16 (14.15)%. Sin embargo no se encontró una diferencia significativa entre los valores registrados en las "distintas" aguadas. Se encontró una correlación significativa entre los valores registrados en las aguadas con los registrados por la estación meteorológica automática (EMA) Calakmul II, por lo que para estudios futuros es posible utilizar los valores de la EMA para representar la dinámica en las aguadas. Entre las estrategias para reducir los potenciales efectos del cambio climático para la fauna es la conservación de las aguadas manteniendo la conectividad entre las mismas
Antioxidants and Oxidative Stress in Children: Influence of Puberty and Metabolically Unhealthy Status
Oxidative stress could help explain the relationship between childhood obesity and a
metabolically unhealthy (MU) status. Moreover, puberty could also influence this relationship,
since it entails physiological cardiometabolic changes. We aimed to evaluate plasma antioxidants
and oxidative stress biomarkers in MU and metabolically healthy (MH) prepubertal and pubertal
children and their associations with pro-inflammatory and endothelial damage biomarkers, taking
puberty into account. A total of 1444 Spanish children aged 3–17 years (48.9% males, 66% prepubertal,
47.1% with obesity) were recruited. Blood pressure, anthropometric and biochemical parameters
were measured, and children were categorized as having a MU or MH status according to risk factors.
Retinol, carotenes, tocopherols, total antioxidant capacity (TAC), oxidized low-density lipoprotein
and selected pro-inflammatory and endothelial damage biomarkers were analyzed. General linear
models adjusted for age, sex, recruitment center and body mass index, partial correlations and
stepwise linear regressions were performed. Lower carotenes and tocopherols levels were found in
MU than in MH children. Plasma TAC was lower in prepubertal and higher in pubertal children with
obesity compared to normal-weight children. Antioxidants and oxidative stress biomarkers showed
novel associations with several pro-inflammatory and endothelial damage biomarkers, with pubertal
differences, supporting the importance of considering both the antioxidant and oxidative stress status
and puberty in the prevention of metabolic diseases in childhood.Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I + D + I), Instituto de Salud Carlos III-Health Research Funding (FONDOS FEDER)
PI051968
PI11/01425
PI1102042
PI11/02059
PI16/01301
PI16/012
PI1600871CIBEROBN Network
CB12/03/30038
CB15/00131
CB15/0004
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