242 research outputs found

    The KKˉπK \bar K \pi decay of the f1(1285)f_1(1285) and its nature as a KKˉccK^* \bar K -cc molecule

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    We investigate the decay of f1(1285)πKKˉf_1(1285) \to \pi K \bar K with the assumption that the f1(1285)f_1(1285) is dynamically generated from the KKˉccK^* \bar{K} - cc interaction. In addition to the tree level diagrams that proceed via f1(1285)KKˉccπKKˉf_1(1285) \to K^* \bar{K} - cc \to \pi K \bar K, we take into account also the final state interactions of KKˉKKˉK \bar K \to K \bar K and πKπK\pi K \to \pi K. The partial decay width and mass distributions of f1(1285)πKKˉf_1(1285) \to \pi K \bar K are evaluated. We get a value for the partial decay width which, within errors, is in fair agreement with the experimental result. The contribution from the tree level diagrams is dominant, but the final state interactions have effects in the mass distributions. The predicted mass distributions are significantly different from phase space and tied to the KKˉccK^* \bar{K} - cc nature of the f1(1285)f_1(1285) state.Comment: Published versio

    Study of BBˉB\bar{B}^* and BBˉB^*\bar{B}^* interactions in I=1I=1 and relationship to the Zb(10610)Z_b(10610), Zb(10650)Z_b(10650) states

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    We use the local hidden gauge approach in order to study the BBˉB\bar{B}^* and BBˉB^*\bar{B}^* interactions for isospin I=1. We show that both interactions via one light meson exchange are not allowed by OZI rule and, for that reason, we calculate the contributions due to the exchange of two pions, interacting and noninteracting among themselves, and also due to the heavy vector mesons. Then, to compare all these contributions, we use the potential related to the heavy vector exchange as an effective potential corrected by a factor which takes into account the contribution of the others light mesons exchange. In order to look for poles, this effective potential is used as the kernel of the Bethe-Salpeter equation. As a result, for the BBˉB\bar{B}^* interaction we find a loosely bound state with mass in the range 105871060110587-10601 MeV, very close to the experimental value of the Zb(10610)Z_b(10610) reported by Belle Collaboration. For the BBˉB^*\bar{B}^* case, we find a cusp at 1065010650 MeV for all spin J=0,1,2J=0,\,1,\,2 cases.Comment: 23 pages, 20 figure

    Wave functions of composite hadron states and relationship to couplings of scattering amplitudes for general partial waves

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    In this paper we present the connection between scattering amplitudes in momentum space and wave functions in coordinate space, generalizing previous work done for s-waves to any partial wave. The relationship to the wave function of the residues of the scattering amplitudes at the pole of bound states or resonances is investigated in detail. A sum rule obtained for the couplings provides a generalization to coupled channels, any partial wave and bound or resonance states, of Weinberg's compositeness condition, which was only valid for weakly bound states in one channel and s-wave. An example, requiring only experimental data, is shown for the ρ\rho meson indicating that it is not a composite particle of ππ\pi \pi but something else

    Isospin breaking and f0(980)f_0(980)-a0(980)a_0(980) mixing in the η(1405)π0f0(980)\eta(1405) \to \pi^{0} f_0(980) reaction

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    We make a theoretical study of the η(1405)π0f0(980)\eta(1405) \to \pi^{0} f_0(980) and η(1405)π0a0(980)\eta(1405) \to \pi^{0} a_0(980) reactions with an aim to determine the isospin violation and the mixing of the f0(980)f_0(980) and a0(980)a_0(980) resonances. We make use of the chiral unitary approach where these two resonances appear as composite states of two mesons, dynamically generated by the meson-meson interaction provided by chiral Lagrangians. We obtain a very narrow shape for the f0(980)f_0(980) production in agreement with a BES experiment. As to the amount of isospin violation, or f0(980)f_0(980) and a0(980)a_0(980) mixing, assuming constant vertices for the primary η(1405)π0KKˉ\eta(1405)\rightarrow \pi^{0}K\bar{K} and η(1405)π0π0η\eta(1405)\rightarrow \pi^{0}\pi^{0}\eta production, we find results which are much smaller than found in the recent experimental BES paper, but consistent with results found in two other related BES experiments. We have tried to understand this anomaly by assuming an I=1 mixture in the η(1405)\eta(1405) wave function, but this leads to a much bigger width of the f0(980)f_0(980) mass distribution than observed experimentally. The problem is solved by using the primary production driven by ηKKˉ\eta' \to K^* \bar K followed by KKπK^* \to K \pi, which induces an extra singularity in the loop functions needed to produce the f0(980)f_0(980) and a0(980)a_0(980) resonances. Improving upon earlier work along the same lines, and using the chiral unitary approach, we can now predict absolute values for the ratio Γ(π0,π+π)/Γ(π0,π0η)\Gamma(\pi^0, \pi^+ \pi^-)/\Gamma(\pi^0, \pi^0 \eta) which are in fair agreement with experiment. We also show that the same results hold if we had the η(1475)\eta(1475) resonance or a mixture of these two states, as seems to be the case in the BES experiment

    A Link between Parental Psychopathology and Preschool Depression: Take Care of Parents to Take Care of Children

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    There is a lot of evidence in the literature showing that early-onset depression determines an emotional and cognitive vulnerability for psychiatric disorders in subsequent years. Aims: The first aim of this outcome research was to analyze the impact of parental support treatment in a sample of depressed preschool children divided into two groups of comparison (under-reactive and over-reactive) through evolution in the Clinical Global Impression (CGI). The second aim was to analyze the correlation between the presence of parental psychopathology and the severity of children's disorders. Methods: Our clinical sample consisted of 32 preschool-age children with a final diagnosis of MDD. The children's assessment included a psychiatric assessment to establish a diagnosis of MDD, confirmed by means of a semi-structured interview, which was administered again one month after the end of parental treatment. All the parents began a six-month parent training treatment conducted by experienced child psychiatrists, whereas children were not treated. During this period, the Clinical Global Impression Scale (CGI) was filled out monthly in order to observe the evolution of the children's disorders. Results: Post-hoc tests showed a significant difference from before the treatment to after the treatment only in the over-reactive group (p = 0.00). Regarding parental psychiatric disorders, in the over-reactive group, only 3 children had no parents with psychopathology. In the under-reactive group, no child lacked a parent with psychopathology. Conclusion: Parent training treatment seems to be a valid intervention to improve preschool depression, especially in over-reactive groups, and to prevent dysfunctional parental styles connected to parental psychopathology

    Functional assessment of cancer therapy questionnaire for breast cancer (FACT-B+4): Italian version validation

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    BACKGROUND: Improvements in breast cancer diagnosis and treatment led to an increased incidence of survivors' rate. The healthcare system has to face new problems related not only to the treatment of the disease, but also to the management of the quality of life after the diagnosis. The aim of this study was to validate the Italian version of the Functional Assessment of Cancer Therapy - Breast (FACT-B+4) questionnaire and to evaluate its reliability. METHODS: The questionnaire was administered twice, with an interval of three days between each administration, to a cohort of women of the Breast Surgical Unit, PoliclincoUmberto I. Cronbach's alpha was used as a measure of the internal consistency of the Italian version. RESULTS: The Italian version of the tool was administered to 55 subjects. The Cronbach's alpha for most scores registered values >0.7, both at baseline and at the follow-up analysis, therefore the subscale showed good internal consistency. CONCLUSIONS: The Italian version of FACT-B+4 demonstrated acceptable reliability properties in the Breast Unit patients. The use of this questionnaire seemed to be effective and in line with the results derived from the English and Spanishversions. Internal consistency and validity had similar performance results

    The X(3872)J/ψγX(3872) \to J/\psi \gamma decay in the DDˉD \bar D^* molecular picture

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    From a picture of the X(3872) where the resonance is a bound state of DˉDc.c.\bar{D}D^*-c.c., we evaluate the decay width into the J/ψγJ/\psi \gamma channel, which is sensitive to the internal structure of this state. For this purpose we evaluate the loops through which the X(3872) decays into its components, and the J/ψJ/\psi and the photon are radiated from these components. We use the local hidden gauge approach extrapolated to SU(4) with a particular SU(4) breaking. The radiative decay involves anomalous couplings and we obtain acceptable values which are compared to experiments and results of other calculations. Simultaneusly, we evaluate the decay rate for the X(3872) into J/ψωJ/\psi \omega and J/ψρJ/\psi \rho, and the results obtained for the ratio of these decay widths are compatible with the experiment. We also show the grossly unacceptable results that come from taking only the Dˉ0D0+c.c.\bar{D}^0D^{*0}+c.c. component.Comment: 17 pages, 2 figure

    Meson-baryon components in the states of the baryon decuplet

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    We apply an extension of the Weinberg compositeness condition on partial waves of L = 1 and resonant states to determine the weight of the meson-baryon component in the Delta(1232) resonance and the other members of the baryon decuplet. We obtain an appreciable weight of pi N in the Delta(1232) wave function, of the order of 60%, which looks more natural when one recalls that experiments on deep inelastic and Drell Yan give a fraction of pi N component of 34% for the nucleon. We also show that, as we go to higher energies in the members of the decuplet, the weights of the meson-baryon component decrease and they already show a dominant part for a genuine, non-meson-baryon, component in the wave function. We write a section to interpret the meaning of the Weinberg sum rule when it is extended to complex energies and another one for the case of an energy-dependent potential

    Development of the Gastrointestinal Tract in Newborns as a Challenge for an Appropriate Nutrition: A Narrative Review

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    The second and third trimesters of pregnancy are crucial for the anatomical and functional development of the gastrointestinal (GI) tract. If premature birth occurs, the immaturity of the digestive and absorptive processes and of GI motility represent a critical challenge to meet adequate nutritional needs, leading to poor extrauterine growth and to other critical complications. Knowledge of the main developmental stages of the processes involved in the digestion and absorption of proteins, carbohydrates, and lipids, as well as of the maturational phases underlying the development of GI motility, may aid clinicians to optimize the nutritional management of preterm infants. The immaturity of these GI systems and functions may negatively influence the patterns of gut colonization, predisposing to an abnormal microbiome. This, in turn, further contributes to alter the functional, immune, and neural development of the GI tract and, especially in preterm infants, has been associated with an increased risk of severe GI complications, such as necrotizing enterocolitis. Deeper understanding of the physiological colonization patterns in term and preterm infants may support the promotion of these patterns and the avoidance of microbial perturbations associated with the development of several diseases throughout life. This review aims to provide a global overview on the maturational features of the main GI functions and on their implications following preterm birth. We will particularly focus on the developmental differences in intestinal digestion and absorption functionality, motility, gut–brain axis interaction, and microbiomes
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