3,301 research outputs found
Open-DO: Open Framework for Critical Systems
Critical systems development pushes software quality to the extreme. When human life depends on the correct operation of the software, strict processes are put in place to ensure, as much as possible, the absence of errors in the airborne system. These processes are very tool-demanding, and these tools also need to follow stringent and rigorous guidelines to provide the proper guarantees of quality. The Open-DO initiative aims at providing a framework federating open-source tools for safety-critical systems. A key point is that these tools will come with the material to ensure that industrial users can trust their output and use them to develop software compliant to the highest integrity levels
A model of maxilla resection to test new hybrid implants:macroporous titanium and tissue engineering elements
Maxillary bone loss in commonly found in humans, due to bone ageing, tooth loos, periodontal disease and, more severely, to trauma, radiotherapy and tumor resection. Masillofacial reconstructive surgery is a still unmet clinical demand, available therapies include grafting of autologous or heterologous bone tissue and/or the implantation of metallic plates, buy these treatments are still unable to resume form and function. The emrgence of 3D-printing technology applied to metal alloys now allows the manufacturing of customized, patient-tailored prosthetic implants. However, poor bone quiality at the implant site due to ageing or disease still hamper proper osseointegration. By combining Electron Beam Melting metal sintering and tissue engineering, we are developing hybrid maxillofacial implants, wher a metal framework of Ti6Al4V alloy confers both and appropiaate shape and mechanical stabilty, while stem cells and osteogenic molecules stimulate bone growth into the metal framework, thus pormoting osseointegration. We hereby present the in vitro work driving to the development of our hybrid maxillofacial prostheses, as well as the setting up of an in vivo model of complete maxilla full resection, created in order to test the prostheses in a preclinical studyUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Landscape Assessment via Regression Analysis
This paper presents a methodology for assessing the visual quality of agricultural landscapes through direct and indirect techniques of landscape valuation. The first technique enables us to rank agricultural landscapes on the basis of a survey of public preferences. The latter weighs the contribution of the elements and attributes contained in the picture to its overall scenic beauty via regression analysis. The photos used in the survey included man-made elements, positive and negative, agricultural fields, mainly of cereals and olive trees, and a natural park. The results show that perceived visual quality increases, in decreasing order of importance, with the degree of wilderness of the landscape, the presence of well-preserved man-made elements, the percentage of plant cover, the amount of water, the presence of mountains and the colour contrast.landscape assessment, visual quality, landscape elements, landscape value, Land Economics/Use, H41, Q21, Q26,
Geodesic vulnerability approach for identification of critical buses in power systems
One of the most critical issues in the evaluation of power systems is the identification of critical buses. For this purpose, this paper proposes a new methodology that evaluates the substitution of the power flow technique by the geodesic vulnerability index to identify critical nodes in power grids. Both methods are applied comparatively to demonstrate the scope of the proposed approach. The applicability of the methodology is illustrated using the IEEE 118-bus test system as a case study. To identify the critical components, a node is initially disconnected, and the performance of the resulting topology is evaluated in the face of simulations for multiple cascading faults. Cascading events are simulated by randomly removing assets on a system that continually changes its structure with the elimination of each component. Thus, the classification of the critical nodes is determined by evaluating the resulting performance of 118 different topologies and calculating the damage area for each of the disintegration curves of cascading failures. In summary, the feasibility and suitability of complex network theory are justified to identify critical nodes in power systems
Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates III: Accurate Radius and Period for OGLE-TR-111-b
We present accurate V-band photometry for a planetary transit of OGLE-TR-111
acquired with VIMOS at the ESO Very Large Telescope. The measurement of this
transit allows to refine the planetary radius, obtaining R_p= 1.01 +/- 0.06
R_J. Given the mass of M_p = 0.53 M_J previously measured from radial
velocities, we confirm that the density is rho_p= 0.6 +/- 0.2 g/cm^3. We also
revise the ephemeris for OGLE-TR-111-b, obtaining an accurate orbital period P=
4.014484 +/- 0.000014 days, and predicting that the next observable transits
would occur around December 2006, and after that only in mid-2008. Even though
this period is different from previously published values, we cannot yet rule
out a constant period.Comment: 16 pages (including figures), 5 figures, 1 table. Accepted for
publication in the Astrophysical Journa
Drosophila Imaginal Discs as a Playground for Genetic Analysis: Concepts, Techniques and Expectations for Biomedical Research
Drosophila imaginal discs are epithelial tissues perfectly suited to use them as a playground to define the functional contribution of genes to epithelial development and organ morphogenesis. The more we know about the discs and the mechanisms directing their development, the best prepared we are to assign specific “functions” to individual genes based on phenotypic observations. Conversely, and thinking from the perspective of the gene, the more we know about its function, the best inferences we could make about the mechanisms underlying imaginal disc development. This reciprocal relationship, coupled to the arsenal of possible experimental approaches available in Drosophila genetics, genomics and cellular biology, makes these tissues excellent systems to address biological problems with biomedical relevance. In this review, an overview of three interconnected aspects related to the use of Drosophila imaginal discs as an experimental system to analyze gene function is given: (i) imaginal discs biology, with a focus in the genetic mechanisms involved in pattern formation; (ii) concepts and available experimental tools for the analyses of gene function and (iii) uses of Drosophila and the imaginal discs for addressing biomedical problems
Parsimonious scenario for the emergence of viroid-like replicons de novo
This article belongs to the Special Issue Viroid-2018: International Conference on Viroids and Viroid-Like RNAs.Viroids are small, non-coding, circular RNA molecules that infect plants. Different hypotheses for their evolutionary origin have been put forward, such as an early emergence in a precellular RNA World or several de novo independent evolutionary origins in plants. Here, we discuss the plausibility of de novo emergence of viroid-like replicons by giving theoretical support to the likelihood of different steps along a parsimonious evolutionary pathway. While Avsunviroidae-like structures are relatively easy to obtain through evolution of a population of random RNA sequences of fixed length, rod-like structures typical of Pospiviroidae are difficult to fix. Using different quantitative approaches, we evaluated the likelihood that RNA sequences fold into a rod-like structure and bear specific sequence motifs facilitating interactions with other molecules, e.g., RNA polymerases, RNases, and ligases. By means of numerical simulations, we show that circular RNA replicons analogous to Pospiviroidae emerge if evolution is seeded with minimal circular RNAs that grow through the gradual addition of nucleotides. Further, these rod-like replicons often maintain their structure if independent functional modules are acquired that impose selective constraints. The evolutionary scenario we propose here is consistent with the structural and biochemical properties of viroids described to date.P.C. is supported by a Ramón Areces Foundation Postdoctoral Fellowship. The Spanish Ministerio de Ciencia, Innovación y Universidades-FEDER funds of the European Union support Projects BASIC (PGC2018-098186-B-I00, J.A.C. and P.C.), MiMevo (FIS2017-89773-P, S.M.), and EvolSysVir (BFU2015-65037-P, S.F.E.)
Primary pleural myxoid liposarcoma: case report and literature review
Myxoid liposarcoma is a histological subtype of malignant tumors within the group of sarcomas. It is more common in men between the ages of 40 and 50 years. Diagnosis is difficult because they are usually asymptomatic lesions, computed tomography (CT) scan and magnetic resonance are the studies of choice. The gold of treatment is surgical resection with free margins. Chemotherapy and radiotherapy have shown a good response. A 46-year-old male was detected incidental mediastinal lesion by radiography, CT scan showed a hypodense lesion in the right hemithorax that extended to the left hemithorax, infiltrating the diaphragm and large vessels. The patient underwent an exploratory thoracotomy, finding a multilobulated tumor and mucous content approximately 600 ml, adjacent structures were infiltrated, so complete resection was not possible. Subsequently, adjuvant chemotherapy given. The histopathological diagnosis was myxoid liposarcoma. Myxoid liposarcoma is a malignant lesion. The primary pleural origin is rare. Surgical resection with free margins has a good prognosis. Due to advanced disease, a complete resection in this case was not possible, that compromised the patient prognosis
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