126 research outputs found
La Guerra de las Ciencias y la Tercera Cultura
Se repasan y analizan los conceptos problemáticos de "tercera cultura" (Snow, 1963; Brockman, 1991) y "guerras de la ciencia" (Andrew Ross, 1995) y la relación entre ellos desde diversas perspectivas científicas, sociológicas, históricas y filosóficas. Finalmente se propone desde la filosofía una interpretación gnoseológica que incide en la pluralidad de las ciencias y que resuelve ciertas imposturas científicas e intelectuales
Biometric parameters and biochemical composition of wild wreckfish (Polyprion americanus)
Wreckfish (Polyprion americanus) is considered to be a good candidate for European
aquaculture. The main biometric parameters were recorded from 86 wild-caught fish (2.6-18
kg of total weight) for 14 months and the gonadosomatic index (GSI), hepatosomatic index
(HIS) and viscerosomatic index (VSI) were obtained. Biochemical analyses of muscle, liver
and gonads from wild wreckfish showed that wreckfish has a high level of protein in
muscle, 84% of dry weight (DW), and low level of lipids (7% DW). Capture season, sex, size
or weight of the fish did not have a strong effect on the variability observed in the levels of
proteins, lipids and fatty acids of the different tissues. Reared wreckfish have more lipids in
mature gonads than wild fish, which may be due to a more lipid-rich diet. However, some
polyunsaturated fatty acids (PUFA) such as arachidonic acid (ARA) and docosahexaenoic acid
(DHA) reached higher values in wild female gonads than in reared gonads, which could
indicate the wreckfish has high requirements in these fatty acids. This study obtained
valuable data on the biology and biochemical composition of wreckfish to estimate its
nutritional requirements, which could be useful for the future of this species in aquaculture.European Union's Seventh Framework Programme Research, Technological development and demonstration (KBBE-2013-07)Postprint1,48
Etiología de las infecciones del sitio quirúrgico en pacientes intervenidos de cirugía cardiaca
ResumenIntroducciónLas infecciones del sitio quirúrgico (ISQ) en pacientes sometidos a cirugía cardiaca constituyen una complicación relevante que puede incrementar la estancia hospitalaria y la morbimortalidad.MétodoAnálisis de las ISQ tras cirugía cardiaca en pacientes del estudio de prevalencia de infecciones en hospitales españoles (EPINE) durante el período 1999-2006.ResultadosDurante el período de tiempo considerado se diagnosticaron 189casos de ISQ en pacientes sometidos a cirugía cardiaca. Noventa y cinco pacientes (50,3%) habían sido sometidos a cirugía valvular y 94 (49,7%) a bypass coronario. La edad media fue de 62,8años (mediana 69). Las ISQ que se evidenciaron fueron infección incisional superficial (69pacientes, 37%), incisional profunda (68enfermos, 36%) y de órgano o espacio (52enfermos, 27%). Se aislaron 180especies bacterianas en los pacientes analizados. Los microorganismos aislados con más frecuencia fueron estafilococos coagulasa negativo (37%), Staphylococcus aureus sensible a meticilina (15,5%), S.aureus resistente a meticilina (6,6%), Enterococcus spp, (6,1%), Escherichia coli (5%), Enterobacter cloacae (5%) y Serratia marcescens (4,4%). No se detectaron diferencias significativas en la etiología al comparar casos de ISQ tras cirugía valvular y cirugía coronaria ni al hacerlo entre infecciones incisionales e infecciones de órgano o espacio.ConclusiónLos estafilococos coagulasa negativos y S.aureus produjeron la mayoría de ISQ tras cirugía cardiaca. No hubo diferencias en la etiología en relación con el tipo de intervención ni con la profundidad de la infección.AbstractIntroductionSurgical site infections (SSIs) in patients undergoing cardiac surgery are a significant complication that causes increased hospital stay and morbi-mortality.MethodAnalysis of SSIs after cardiac surgery in patients included in the EPINE study (study of the prevalence of infections in Spanish hospitals) during the period 1999-2006.ResultsDuring the considered period it was detected 189cases of SSIs in patients undergoing cardiac surgery. Ninety-five patients (50.3%) had undergone heart valve surgery and 94patients (49.7%) had undergone coronary bypass. The mean age was 62.8years (median 69). SSIs that were observed consisted in superficial incisional infection (69patients, 37%), deep incisional (68patients, 36%) and organ or space (52patients, 27%). One hundred eighty bacterial species were isolated in these patients. The most frequently isolated microorganisms were coagulase-negative staphylococci (37%), methicillin sensitive Staphylococcus aureus (15.5%), methicillin resistant S.aureus (6.6%), Enterococcus spp (6.1%), Escherichia coli (5%), Enterobacter cloacae (5%) and Serratia marcescens (4.4%). There were no significant differences in etiology when comparing cases of SSI after valve surgery and coronary bypass surgery or did between incisional infections and organ or space infections.ConclusionCoagulase-negative staphylococci and S.aureus caused the majority of SSIs after cardiac surgery. There were no differences in the etiology in relation to the type of surgery or the depth of the infection
Using Markov-Switching models in US stocks optimal portfolio selection in a Black–Litterman context (Part 1)
In this study, we tested the benefit of using Markov-Switching (M-S) models to forecast the views of the 26 most traded stocks in the US in a Black–Litterman (B–L) optimal selection context. With weekly historical data of these stocks from 1 January 1980, we estimated and simulated (from 7 January 2000, to 7 February 2022) three portfolios that used M-S views in each stock and blended them with the market equilibrium views in a B–L context. Our position was that the B–L optimal portfolios could generate alpha (extra return) against a buy-and-hold and an actively managed portfolio with sample portfolio parameters (à la Markowitz, SampP). Our results suggest that the outperformance of the B–L managed portfolios holds only in the short term. In the long-term, the performance of the B–L portfolios, the SampP, and the market portfolio are statistically equal in terms of returns or their mean–variance efficiency in an ex-ante or ex-post analysis.Junta de Extremadur
Routing, Modulation and Spectrum Assignment Algorithm Using Multi-Path Routing and Best-Fit
Producción CientíficaElastic Optical Networks (EONs) are a promising optical technology to deal with the ever-increasing traffic and the vast number of connected devices of the next generation of the Internet, associated to paradigms like the Internet of Things (IoT), the Tactile Internet or the Industry 4.0, to name just a few. In this kind of optical network, each optical circuit or lightpath is provisioned by means of superchannels of variable bandwidth. In this manner, only the necessary bandwidth to accommodate the demand is allocated, improving the spectrum usage. When establishing a connection, the EON control layer determines the modulation format to be used and allocates a portion of the spectrum in a sequence of fibers from the source to the destination node providing the user-demanded bandwidth. This is known as the routing, modulation level and spectrum assignment (RMSA) problem. In this work, we firstly review the most important contributions in that area, and then, we propose a novel RMSA algorithm, multi-path best-fit (MP-BF), which uses a split spectrum multi-path strategy together with a spectrum assignment technique (best-fit), and which jointly exploit the flexibility of EONs. A simulation study has been conducted comparing the performance of EONs when using MP-BF with other proposals from the literature. The results of this study show that, by using MP-BF, the network can increase its performance in terms of lightpath request blocking ratio and supported traffic load, without affecting the energy per bit or the computation time required to find a solution
International Conference on Broadband Communications, Networks and Systems
Producción CientíficaNetwork Function Virtualization (NFV) is considered to be one of the enabling technologies for 5G. NFV poses several challenges, like deciding the virtual network function (VNF) placement and chaining, and adding backup resources to guarantee the survivability of service chains. In this paper, we propose a genetic algorithm that jointly solves the VNF-placement, chaining and virtual topology design problem in WDM metro ring network, with the additional capacity of providing node protection. The simulation results show how important is to solve all of these subproblems jointly, as well as the benefits of using shared VNF and network resources between backup instances in order to reduce both the service blocking ratio and the number of active CPUs.Ministerio de Economía, Industria y Competitividad (grant TEC2017-84423-C3-1-P)Ministerio de Industria, Comercio y Turismo (grant BES 2015-074514)INTERREG V-A España-Portugal (POCTEP) (grant 0677_DISRUPTIVE_2_E)
The human VGF-derived bioactive peptide TLQP-21 binds heat shock 71 kDa protein 8 (HSPA8) on the surface of SH-SY5Y cells
VGF (non-acronymic)is a secreted chromogranin/secretogranin that gives rise to a number of bioactive peptides by a complex proteolysis mechanism. VGF-derived peptides exert an extensive array of biological effects in energy metabolism, mood regulation, pain, gastric secretion function, reproduction and, perhaps, cancer. It is therefore surprising that very little is known about receptors and binding partners of VGF-derived peptides and their downstream molecular mechanisms of action. Here, using affinity chromatography and mass spectrometry-based protein identification, we have identified the heat shock cognate 71 kDa protein A8 (HSPA8)as a binding partner of human TLQP-21 on the surface of human neuroblastomaSH-SY5Y cells. Binding of TLQP-21 to membrane associated HSPA8 in live SH-SY5Y cells was further supported by cross-linking to live cells. Interaction between HSPA8 and TLQP-21 was confirmed in vitro by label-free Dynamic Mass Redistribution (DMR) studies. Furthermore, molecular modeling studies show that TLQP-21 can be docked into the HSPA8 peptide binding pocket. Identification of HSPA8 as a cell surface binding partner of TLQP-21 opens new avenues to explore the molecular mechanisms of its physiological actions, and of pharmacological modulation thereof.This work was supported by ERANETNEURON grant DISCover through the Spanish
funding partner Instituto de Salud Carlos III (www.isciii.es), grant: PI09/2688 to JRRS
A testbed and a simulation laboratory for training engineering students in optical access network technologies
Producción CientíficaEngineering profiles focused on next-generation optical networks are gaining immense importance due to new emerging services and the amount of data expected in future network scenarios. In fact, not only are optical access networks leading to a major revolution in the network industry, but passive optical networks are the most widely deployed access networks worldwide today. This should be a strong incentive for universities to train their students in these innovative and recent technologies. In this vein, we propose the deployment of an optical communication laboratory with on-site experimental sessions in which students work with commercial equipment and realistic working environments. These working environments are necessary to train professionals in the area of optical networks. However, due to the high cost of the optical communications equipment, it is not possible to have a working place for each group and we combine these experimental sessions with some simulation sessions to complete the training. We present the design of this lab and a qualitative and quantitative study aimed at analyzing students’ experiences, the skills they have acquired, and the potential impact on their future careers. This study shows that students have a very positive perception of the lab, emphasizing that working with real equipment helps them improve technical skills and assimilate theoretical knowledge. They also point out they would like a higher number of subjects in their degrees to employ this type of lab. Finally, students perceive these sessions as very useful for their professional future.Unión Europea a través del programa INTERREG V-A España-Portugal (project 0677_DISRUPTIVE_2_E)Junta de Castilla y León (grant VA085G19)Ministerio de Ciencia, Innovación y Universidades (grants TEC2017-84423-C3-1-P and RED2018-102585-T
2020 22nd International Conference on Transparent Optical Networks (ICTON)
Producción CientíficaNetwork Function Virtualization (NFV) is a promising networking paradigm that will ease the network manageability and increase its flexibility, while reducing costs. In this paradigm, operators must solve the Virtual Network Function (VNF) placement and chaining problems. It is also important to provide backup resources to ensure the survivability of the offered services when a node failure happens. In this paper, we compare two different protection approaches to ensure the service resilience: individual VNF protection and end-to-end protection. Results show the benefits in terms of use of computing resources and energy consumption of protecting each VNF individually, compared to the end-to-end protection approach.Ministerio de Economía, Industria y Competitividad (grant TEC2017-84423-C3-1-P)Ministerio de Industria, Comercio y Turismo (fellowship BES-2015-074514)Research network Go2Edge (grant RED2018-102585-T)Interreg V-A Spain-Portugal (POCTEP) programme 2014- 202
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