Search results for "Parto"
showing 10 items of 608 documents
First measurement of the Sivers asymmetry for gluons using SIDIS data
2017
The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. It was extracted from measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it turned out to be non-zero for quarks. In this letter the evaluation of the Sivers asymmetry for gluons in the same process is presented. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon-gluon fusion, QCD Compton scattering and leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simul…
Features of W production in p-p, p-Pb and Pb-Pb collisions
2017
We consider the production of inclusive W bosons in variety of high-energy hadronic collisions: p--p, p--$\overline{\rm p}$, p--Pb, and Pb--Pb. In particular, we focus on the resulting distributions of charged leptons from W decay that can be measured with relatively low backgrounds. The leading-order expressions within the collinearly factorized QCD indicate that the center-of-mass energy dependence at forward/backward rapidities should be well approximated by a simple power law. The scaling exponent is related to the small-$x$ behaviour of the quark distributions, which is largely driven by the parton evolution. An interesting consequence is the simple scaling law for the lepton charge as…
Event-by-event picture for the medium-induced jet evolution
2016
We discuss the evolution of an energetic jet which propagates through a dense quark-gluon plasma and radiates gluons due to its interactions with the medium. Within perturbative QCD, this evolution can be described as a stochastic branching process, that we have managed to solve exactly. We present exact, analytic, results for the gluon spectrum (the average gluon distribution) and for the higher n-point functions, which describe correlations and fluctuations. Using these results, we construct the event-by-event picture of the gluon distribution produced via medium-induced gluon branching. In contrast to what happens in a usual QCD cascade in vacuum, the medium-induced branchings are quasi-…
Impacto del trauma perineal postparto en la salud física y sexual en mujeres primíparas al año del nacimiento
2018
Introducción: La episiotomía es una práctica común en la atención al parto vaginal. Las recomendaciones aconsejan tasas inferiores al 15% en partos espontáneos ya que su práctica presenta un mayor riesgo de disfunciones sobre el suelo pélvico. La episiotomía en España está poco investigada tanto a nivel de práctica como de los efectos que la misma puede tener sobre la salud de la mujer a lo largo de su ciclo reproductivo y vital. Objetivo: Estudiar el impacto de la práctica de la episiotomía sobre la función del suelo pélvico en mujeres primíparas con partos espontáneos al año de postparto. Material y métodos: Se realiza un estudio unicéntrico, observacional analítico, de cohortes retrospec…
High-energy resummation effects in the production of Mueller-Navelet dijet at the LHC
2016
We study the production of two forward jets with a large interval of rapidity at hadron colliders, which was proposed by Mueller and Navelet as a possible test of the high energy dynamics of QCD, within a complete next-to-leading logarithm framework. We show that using the Brodsky-Lepage-Mackenzie procedure to fix the renormalization scale leads to a very good description of the recent CMS data at the LHC for the azimuthal correlations of the jets. We show that the inclusion of next-to-leading order corrections to the jet vertex significantly reduces the importance of energy-momentum non-conservation which is inherent to the BFKL approach, for an asymmetric jet configuration. Finally, we ar…
Uncertainties on the determination of the strong coupling αs from the energy evolution of jet fragmentation functions at low z
2014
The QCD coupling alpha_s is determined at NLO*+NMLLA accuracy from the comparison of experimental jet data to theoretical predictions of the energy-evolution of the parton-to-hadron fragmentation function moments (multiplicity, peak, width, skewness) at low fractional hadron momentum z. From the existing e+e- and e-p jet data, we obtain alpha_s(m_Z^2) = 0.1195 +/- 0.0021 (exp.) {+0.0015}_{-0.0} (scale) at the Z mass. The uncertainties of the extracted alpha_s value are discussed.
Confronto tra la produzione di latte d’asina nell’arco di una intera lattazione e quella ottenibile nei primi 6 mesi
2008
Rosenbluth separation of the $\pi^0$ Electroproduction Cross Section off the Neutron
2017
We report the first longitudinal/transverse separation of the deeply virtual exclusive $\pi^0$ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions $d\sigma_L/dt$, $d\sigma_T/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{TT}/dt$ are extracted as a function of the momentum transfer to the recoil system at $Q^2$=1.75 GeV$^2$ and $x_B$=0.36. The $ed \to ed\pi^0$ cross sections are found compatible with the small values expected from theoretical models. The $en \to en\pi^0$ cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity GPDs of the nucle…
La atención a la salud materno-infantil en el área de salud de La Ribera (Valencia) desde la perspectiva de las gestantes y las matronas: aproximacio…
2020
Justificación e introducción La atención al parto experimentó profundos cambios durante la segunda mitad del siglo XX con la introducción del parto en el ámbito hospitalario. Como reacción a ello surge el movimiento del parto normal, que pretende humanizar la asistencia al parto que se presta dentro de los hospitales. En cada hospital este proceso se ha desarrollado en diferente tiempo y forma. En el caso del Hospital Universitario de La Ribera (Alzira, Valencia), la introducción de los protocolos de atención al parto normal se produce de forma progresiva entre los años 2011 y 2014. En ese momento, surge la necesidad de explorar la acogida de estos cambios entre las gestantes del área de sa…
Maduración pre-inducción de parto. Comparación entre dinoprostona y misoprostol con objetivación de dinámica uterina mediante electrohisterografía: U…
2019
La inducción del parto y la maduración cervical son temas de gran interés dentro de la obstetricia, llegando a alcanzar el 30% del total de nacimientos. Además, su inadecuada indicación conlleva una iatrogenia considerable respecto a los resultados neonatales, el aumento de la tasa de cesáreas y los costes. Si bien disponemos de muchos métodos con una efectividad y seguridad contrastada, la investigación en busca del método óptimo para la maduración cervical en cuellos uterinos desfavorables continúa en marcha. Actualmente las prostaglandinas Dinoprostona y Misoprostol son los agentes maduradores de primera elección en nuestro medio. Entre los diferentes estudios publicados, existe heteroge…