917 research outputs found

    Experimental methods and prospects on the measurement of electroweak bb and cc-quark observables at the ILC operating at 250 GeV

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    This paper describes a comprehensive experimental study on viability and prospects for the measurement of electroweak observables in e+ebbˉe^{+}e^{-}\rightarrow b\bar{b} and e+eccˉe^{+}e^{-}\rightarrow c\bar{c} processes at the International Linear Collider (ILC) operating at 250 GeV of centre of mass energy. The ILC will produce electron and positron beams with different degrees of longitudinal polarisation (up to 80%\% for electrons and 30%30\% for positrons). The studies are based on a detailed simulation of the International Large Detector (ILD) concept. This will allow to inspect in detail the four independent chirality combinations of the electroweak couplings to electrons and other fermions and also perform background free analysis. The ILD design is based on the particle flow approach and the excellent vertexing and tracking capabilities, including charged hadron identification thanks to the dE/dxdE/dx. We evaluate the main sources of experimental systematic uncertainties and identify the key design aspects of the accelerator and detector that are crucial to achieve the required per mil level accuracy that matches the expected statistical accuracy.Comment: 35 pages, 21 figures, ILD concept grou

    Two-particle angular correlations in the search for new physics at future e+ee^+e^- colliders

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    The analysis of angular particle correlations can yield valuable insights into the initial state of matter in high-energy collisions, thereby potentially revealing the existence of Beyond the Standard Model scenarios such as Hidden Valley (HV). In this study, we focus on a QCD-like hidden sector with relatively massive HV quarks (100\lesssim 100~GeV) which might enlarge and strengthen azimuthal correlations of final-state SM hadrons. In particular, we study the formation and possible observation of \textit{ridge-like} structures in the angular two-particle correlation function at future e+ee^+e^- colliders, with a much cleaner environment than in hadron colliders, such as the LHC.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS 2023), 15-19 May 2023. C23-05-15.

    Redes de seguridad para cierre vertical de fachadas

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    Among other methods, vertical safety nets on the façades of buildings during the construction stage are used in Spain as an alternative to other safety systems in order to avoid falls to a different level. There are two kinds of such nets: floor-to-ceiling nets - that secure the entire void between successive floors in structure construction stage-, and small nets what secure windows and other minor voids in later stages. Their design and requirements are not defined at present, but the AEN/CTN81/SC2/GT7 Spanish Working Group is drafting a specific regulation named Pr UNE 81651. Some members of the Civil Engineering Department of the University of Alicante, having experience in other systems of protection, have developed several finite-elements numerical models to measure and analyse mechanical variables related to a possible fall of a person over this kind of net, characterised by a kinetic energy lower than for other types. In this paper the obtained results are shown, for both large and little nets, analysing the anchorages gap, void openings at perimeter, maximum net deflection and net disposal (square/diamond) repercussion, as well as its consequences on the victim’s safety (impact factor).Entre otros medios de protección colectiva, en los últimos años se vienen utilizando en España redes verticales de cierre de fachadas, a paño completo entre forjados en fase de estructura, y también para huecos menores como ventanas o puertas, en fases posteriores. Este tipo de protección no cuenta hasta el momento con ningún tipo de regulación oficial, si bien en el grupo de trabajo AEN/CTN81/SC2/GT7 se desarrolla actualmente el borrador de la norma Pr UNE 81651 a tal fin. Desde el Dtº. de Ing. de la Construcción de la Universidad de Alicante, varios miembros del grupo de trabajo han desarrollado, contando con la experiencia en otros sistemas de protección, algunos modelos numéricos con elementos finitos para valorar y cuantificar variables mecánicas asociadas al episodio de una eventual caída de una persona sobre este tipo de redes, caracterizado por una menor energía cinética que para otros tipos de ellas. En el artículo se exponen los resultados obtenidos para ambos tipos de paños, grandes y pequeños, donde se han valorado la separación de anclajes de la red, las aberturas generadas en su perímetro durante la retención, los esfuerzos en anclajes y elementos textiles, el factor de impacto que sufriría el accidentado y la repercusión de la disposición geométrica de la red, al cuadro o al rombo

    Sistemas de protección individual anticaídas sometidos a impacto. Simulaciones numéricas

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    Personal fall protection systems are set up by EN-363 to avoid or retain people falls safely (without relevant damages). They are the ultimate resource to prevent a fall after other measures being considered. This paper analyses the variables affecting the system behaviour: free fall height, length of retaining rope, stiffness and damping of retaining material, and worker weight. To this end, fall phenomenon has been simulated with finite elements dynamic models with an elastic rope and a rigid ballast. It allows obtain likely values of maximum forces on the injured and over the system during the impact. Results demonstrate the fundamental role of height fall vs. rope length rate (fall factor), which results more important than the fall height itself. The severe values obtained for maximum forces show that future research would include elastoplastic energy absorbers to decrease impact until reasonable values.Los sistemas anticaída se establecen en UNE-EN-363 para evitar o retener caídas de personas sin que las fuerzas de retención causen daños relevantes. Constituyen el último recurso para prevención de caídas tras considerar otras medidas. Este artículo analiza las variables que afectan al comportamiento del sistema: altura de caída, longitud de cuerda de retención, rigidez y amortiguamiento del material de retención, y peso del operario. A tal fin, el fenómeno ha sido simulado con modelos dinámicos de elementos finitos mediante una cuerda elástica y un lastre rígido. Ello permite obtener valores verosímiles de las máximas fuerzas sobre el accidentado y el sistema durante el impacto. Los resultados demuestran el papel fundamental de la proporción entre altura de caída y longitud de cuerda (factor de caída), más determinante que la propia altura de caída. Las elevadas fuerzas máximas obtenidas indican la necesidad de incluir en el modelo absorbedores de energía elastoplásticos, en futuras investigaciones, con el fin de disminuir el impacto a valores razonables

    Matched sizes of activating and inhibitory receptor/ligand pairs are required for optimal signal integration by human Natural Killer cells

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    It has been suggested that receptor-ligand complexes segregate or co-localise within immune synapses according to their size, and this is important for receptor signaling. Here, we set out to test the importance of receptor-ligand complex dimensions for immune surveillance of target cells by human Natural Killer (NK) cells. NK cell activation is regulated by integrating signals from activating receptors, such as NKG2D, and inhibitory receptors, such as KIR2DL1. Elongating the NKG2D ligand MICA reduced its ability to trigger NK cell activation. Conversely, elongation of KIR2DL1 ligand HLA-C reduced its ability to inhibit NK cells. Whereas normal-sized HLA-C was most effective at inhibiting activation by normal-length MICA, only elongated HLA-C could inhibit activation by elongated MICA. Moreover, HLA-C and MICA that were matched in size co-localised, whereas HLA-C and MICA that were different in size were segregated. These results demonstrate that receptor-ligand dimensions are important in NK cell recognition, and suggest that optimal integration of activating and inhibitory receptor signals requires the receptor-ligand complexes to have similar dimensions

    DQM4HEP - A Generic Online Monitor for Particle Physics Experiments

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    There is currently a lot of activity in R&D for future collider experiments. Multiple detector prototypes are being tested, each one with slightly different requirements regarding the format of the data to be analysed. This has generated a variety of ad-hoc solutions for data acquisition and online data monitoring. We present a generic C++11 online monitoring framework called DQM4HEP, which is designed for use as a generic online monitor for particle physics experiments, ranging from small tabletop experiments to large multi-detector testbeams, such as those currently ongoing/planned at the DESY II or CERN SPS beamlines. We present results obtained using DQM4HEP at several testbeams where the CALICE AHCAL, SDHCAL and SiWECAL detector prototypes have been tested. During these testbeams, online analysis using DQM4HEP's framework has been developed and used. We also present the currently ongoing work to integrate DQM4HEP within the EUDAQ tool. EUDAQ is a tool for common and generic data acquisition within the AIDA-2020 collaboration. This will allow these two frameworks to work together as a generic and complete DAQ and monitoring system for any type of detector prototype tested on beam tests, which is one of the goals of the AIDA-2020 project

    Análisis de la relevancia y factibilidad de indicadores de calidad en las unidades de nutrición

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    Introducción: La evaluación de la calidad en las actividades sanitarias exige la elección de unos indicadores acordes con los resultados que queremos medir. De todos los posibles, debemos priorizar aquellos que nos permitan obtener la información más relevante sin sobrecargar el trabajo habitual de nuestras Unidades. Objetivo: Conocer la opinión de los socios de SENPE respecto a la relevancia y la viabilidad del uso de una selección de indicadores de calidad para su aplicación en nutrición clínica. Métodos: Encuesta remitida mediante correo electrónico a los socios de SENPE solicitando a los mismos su opinión sobre 12 indicadores de calidad, valorándose cada uno en cuanto a su relevancia y factibilidad de la aplicación en su medio. Resultados: Contestaron 40 encuestados de 40 centros diferentes de 12 comunidades autónomas. En general, los indicadores fueron considerados más relevantes que factibles. Los indicadores mejor puntuados fueron: “identificación en las bolsas de nutrición artificial”, “posición semi-incorporada del paciente con nutrición enteral por sonda nasogástrica” y “protocolos clínicos básicos”. Considerando los indicadores por grupos (de estructura, proceso o resultado) los mejor valorados fueron: “identificación del paciente en las bolsas de nutrición artificial” (estructura), “posición semi-incorporada” y “protocolos clínicos básicos” (proceso), y “cumplimiento del objetivo calórico” (resultado). Conclusión: Los resultados de la encuesta permiten seleccionar indicadores prioritarios para su aplicación en las Unidades de NutriciónIntroduction: The quality assessment in health activities requires the choice of indicators in line with the results we want to measure. Of all possible, we should prioritize those that allow us to obtain the most relevant information without overloading the regular work of our units. Objective: To determine the opinion of the members of SENPE regarding the relevance and feasibility of using a selection of quality indicators designed for use in clinical nutrition. Methods: E-mail survey sent to members of SENPE asking them their views on 12 quality indicators, evaluating each in terms of their relevance and feasibility of implementation in their environment. Results: 40 respondents answered from 40 centers in 12 different regions. In general, the indicators were considered more relevant than feasible. The indicators best rated were: “identification in artificial nutrition bags, “semi-recumbent position in patient with nasogastric tube feeding” and “basic clinical protocols”. Considering the type of indicator: “patient identification in the bags of artificial nutrition (structure),” a semi-incorporated “and” basic clinical protocols (process), and “fulfillment of the caloric goal” (result). Conclusion: The results of the survey can make a selection of indicators that could be considered for first-line introduction in a Nutrition Uni

    Hadron shower decomposition in the highly granular CALICE analogue hadron calorimeter

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    The spatial development of hadronic showers in the CALICE scintillator-steel analogue hadron calorimeter is studied using test beam data collected at CERN and FNAL for single positive pions and protons with initial momenta in the range from 10 to 80 GeV/c. Both longitudinal and radial development of hadron showers are parametrised with two-component functions. The parametrisation is fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics lists from Geant4 version 9.6. The parameters extracted from data and simulated samples are compared for the two types of hadrons. The response to pions and the ratio of the non-electromagnetic to the electromagnetic calorimeter response, h/e, are estimated using the extrapolation and decomposition of the longitudinal profiles.Comment: 38 pages, 19 figures, 5 tables; author list changed; submitted to JINS
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