2,806 research outputs found
Robust NMR water signal suppression for demanding analytical applications
We describe the design and application of robust, general-purpose water signal suppression pulse sequences well suited to chemometric work. Such pulse sequences need to deal well with pulse mis-calibrations, radiation damping, chemical exchange, and the presence of sample inhomogeneities, as well as with significant variations in sample characteristics such as pH, ionic strength, relaxation characteristics and molecular weight. Of course, such pulse sequences should produce un-distorted lineshapes and baselines and work well both under automation and in the hands of non-experts. As an example, one such pulse sequences, Robust-5, will be presented. This new pulse sequence meets those criteria and is able to reduce a 50 M proteo water signal down to a 0.9 mM level, without fine tuning, and under automation, and it is therefore well suited to the most demanding of analytical applications
Evolución de fascies abanico aluvial-fluvial-lacustre en el Plioceno de la Depresión de Guadix-Baza
More light on Higgs flavor at the LHC: Higgs boson couplings to light quarks through h+γ production
Feynman diagrams were drawn using t ik z - f eynman . J. A. A. S. acknowledges partial financial support by the Spanish “Agencia Estatal de Investigación” (AEI) through Project No. PID2019–110058GB-C21. The work of J. M. C. was supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (MICIU) and the EU Fondo Social Europeo (FSE) through Grant No. PRE2018-083563. The work of J. M. N. was supported by Ramón y Cajal Fellowship Contract No. RYC-2017-22986, and by Grant No. PGC2018-096646-A-I00 from the Spanish Proyectos de de Generación de Conocimiento. J. M. N. also acknowledges support from the European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska-Curie Grant Agreement No. 860881 (ITN HIDDeN), as well as from the AEI through Grant IFT Centro de Excelencia Severo Ochoa No. SEV-2016-0597.Higgs production in association with a photon at hadron colliders is a rare process, not yet observed at the LHC. We show that this process is sensitive to significant deviations of Higgs couplings to first- and second-generation SM quarks (particularly the up type) from their SM values, and we use a multivariate neural network analysis to derive the prospects of the High Luminosity LHC to probe deviations in the up and charm Higgs Yukawa couplings through h+γ production.Horizon 2020 Framework Programme
860881,SEV-2016-0597 H2020Ministerio de Ciencia, Innovación y Universidades
MCIUEuropean Social Fund
PGC2018-096646-A-I00,PRE2018-083563,RYC-2017-22986 ESFAgencia Estatal de Investigación
PID2019–110058GB-C21 AE
Determination of the home advantage in handball Olympic Games and European Championships
Home advantage (HA) has typically been focused in competitions in which the same number of home games and away games are played, but it should be noted that there are other competitions that take place at the home of only one organizer. In this study, 2,758 games of handball were analyzed. The variables registered were the number of games won, the number of games drawn, the number of games lost, the number of goals scored, the number of goals against and the gender of the competitors. The significance of the level of advantage in playing at home was calculated for the variable of points obtained, assuming the null hypothesis that playing at home has no advantage. The Wilcoxon signed rank was used to contrast home advantage signification. The advantage of playing at home and the advantage of playing away in male and female competitions were compared using the Mann–Whitney test. The significance of the difference between the goals (both scored by and scored against) when a team played at home or played away from home was determined using t tests. Pearson and Spearman bivariate correlations were used to establish the level of association between the classification of a team and the number of points obtained as a result of the advantage of playing at home. No significant advantage to playing at home in the Olympic Games or European Championships was found for either gender. However, a direct association exists between playing at home and the points obtained in a competition. There is also a significant inverse association between playing at home and the final classification of a team
Validation of the questionnaire "focus of attention for handball trainers in video analysis"
El uso del método Delphi es indicado para la elaboración de cuestionarios sobre un tema objeto de estudio en el que no hay mucho conocimiento anterior. Partiendo de una idea inicial, un grupo de 10 expertos en balonmano realizaron una serie de propuestas de modificación hasta llegar a un cuestionario final consensuado de 34 ítems, con preguntas relacionadas con las cuatro fases del juego existente en balonmano. Dicho estudio se pasó a una muestra de 134 entrenadores de cuatro países, verificando la validación del cuestionario. Los entrenadores de balonmano dan mayor importancia en los análisis con vídeo a las fases del juego de ataque y defensa organizada.The use of the Delphi method is indicated for the elaboration of questionnaires on a subject of study, which until now has little known information about it. Starting on an initial proposal, a group of 10 experts in handball made a series of modification proposals until a final questionnaire was agreed of 34 items, with questions related with the four phases of the game that exist in handball. The questionnaire was given to 134 trainers from four different countries, verifying the validation of the questionnaire. The handball trainers gave most importance to the analysis with videos of the phases of play in attack and organized defensepeerReviewe
A machine-learning based solution for chatter prediction in heavy-dutymilling machines
The main productivity constraints of milling operations are self-induced vibrations, especially regenerative chatter vibrations. Two key parameters are linked to these vibrations: the depth of cut achievable without vibrations and the chatter frequency. Both parameters are linked to the dynamics of machine component excitation and the milling operation parameters. Their identification in any cutting direction in milling machine operations requires complex analytical models and mechatronic simulations, usually only applied to identify the worst cutting conditions in operating machines. This work proposes the use of machine learning techniques with no need to calculate the two above-mentioned parameters by means of a 3-step strategy. The strategy combines: 1) experimental frequency responses collected at the tool center point; 2) analytical calculations of both parameters; and, 3) different machine learning techniques. The results of these calculations can then be used to predict chatter under different combinations of milling directions and machine positions. This strategy is validated with real experiments on a bridge milling machine performing concordance roughing operations on AISI 1045 steel with a 125 mm diameter mill fitted with nine cutters at 45°, the results of which have confirmed the high variability of both parameters along the working volume. The following regression techniques are tested: artificial neural networks, regression trees and Random Forest. The results show that Random Forest ensembles provided the highest accuracy with a statistical advantage over the other machine learning models; they achieved a final accuracy of 0.95 mm for the critical depth and 7.3 Hz for the chatter frequency (RMSE) in the whole working volume and in all feed directions, applying a 10 × 10 cross validation scheme. These RMSE values are acceptable from the industrial point of view, taking into account that the critical depth of this range varies between 0.68 mm and 19.20 mm and the chatter frequency between 1.14 Hz and 65.25 Hz. Besides, Random Forest ensembles are more easily optimized than artificial neural networks (1 parameter configuration versus 210 MLPs). Additionally, tools that incorporate regression trees are interesting and highly accurate, providing immediately accessible and useful information in visual formats on critical machine performance for the design engineer.Hidrodamp Project (IDI-20110453) of the Centre for Industrial Technological Development (CDTI
Resultados en la cirugía de revisión de la artroplastia de rodilla con aporte de aloinjerto óseo
Hemos realizado un estudio retrospectivo de 12 pacientes (13 rodillas) intervenidos entre 1975 y 2001 de revisión de prótesis de rodilla utilizando aloinjerto óseo, valorando el resultado funcional y clínico. La edad media fue de 62 años. La indicación primaria fue de gonartrosis primaria en 8 casos (9 rodillas), artrosis postraumática en 1 caso y 2 casos de artritis reumatoide. Los defectos óseos fueron clasificados utilizando la clasificación del Anderson Orthopedic Institute Research. Se utilizó aloinjerto de forma fragmentada en 11 casos y de forma estructural en 2. El seguimiento medio fue de 69 meses. En la valoración clínica se utilizó la escala de la Knee Society; la evaluación radiográfica evaluó la existencia de integración del injerto en el huésped. Los 2 casos de artritis reumatoide presentaron infección profunda protésica y que necesitaron de una artrodesis como solución definitiva. El resto de pacientes mostró unos resultados satisfactorios con buena integración del injerto al huésped. La utilización de aloinjerto fragmentado y estructural en la cirugía de revisión protésica de rodilla resuelve de manera satisfactoria la presencia del defecto óseo, aunque en enfermos con algú tipo de inmunopresión, el elevado riesgo de infección profunda en cirugía de revisión nos obliga a extremar las precauciones.We have carried out a retrospective study of 12 patients (13 knees) treated between 1975 and 2001 after failed total knee arthroplasty (TKA), by means of revision surgery using bone allograft. The mean age was of 62 years. The primary indication was degenerative osteoarthritis in 8 cases (9 knees), postraumatic osteoarthritis in 1 case and rheumatoid artritis in 2 cases. The bony defects were classified according to the Anderson's Orthopedic Institute classification. Fragmented allograft was used in 11 cases and structural allograft in 2. The mean follow-up time was of 69 months. Outcome was evaluated through functional and clinical result. For the clinical evaluation the scale of the Knee Society was used; the radiographic evaluation assessed the degree of integration of the graft. The 2 cases of rheumatoid artritis presented deep infection of the TKA that required an arthrodesis for definitive solution. The rest of patients showed satisfactory results with good integration of the bone graft. The use of fragmented and structural allograft in revision surgery of failed TKA solves in a satisfactory way the presence of bony defects, although in patients with some degree of inmunosupression the high risk of deep infection forces to extreme the cautions
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