2,320 research outputs found
Hints for the existence of hexaquark states in the baryon-antibaryon sector
The discovery of some baryon-antibaryon resonances has led us to consider
3q~3\bar{q} systems as possible candidates. We predict their spectrum in the
framework of a constituent model, where the chromo-magnetic interaction plays
the main role. The relevant parameters are fixed by the present knowledge on
tetraquarks. The emerging scenario complies well with experiment. Besides the
description of the baryon-antibaryon resonances, we find evidence for new
tetraquark states, namely the a0(Y) in the hidden strangeness sector and, in
the cs\bar{c}\bar{s} sector, the Y(4140) and the X(4350). A detailed account of
the spectra and the decay channels is provided for future comparisons with
data.Comment: 17 page
Neutrino masses and mixings in SO(10)
Assuming a Zee-like matrix for the right-handed neutrino Majorana masses in
the see-saw mechanism, one gets maximal mixing for vacuum solar oscillations, a
very small value for and an approximate degeneracy for the two lower
neutrino masses. The scale of right-handed neutrino Majorana masses is in good
agreement with the value expected in a SO(10) model with Pati-Salam SU(4)\ts
SU(2)\ts SU(2) intermediate symmetry.Comment: 11 pages, no figures. References adde
Associated WH production at hadron colliders: a fully exclusive QCD calculation at NNLO
We consider QCD radiative corrections to Standard Model Higgs boson
production in association with a W boson in hadron collisions. We present a
fully exclusive calculation up to next-to-next-to-leading order (NNLO) in QCD
perturbation theory. To perform this NNLO computation, we use a recently
proposed version of the subtraction formalism. Our calculation includes
finite-width effects, the leptonic decay of the W boson with its spin
correlations, and the decay of the Higgs boson into a bbbar pair. We present
selected numerical results at the Tevatron and the LHC.Comment: 7 pages, 2 figure
Learning Linear Non-Gaussian Polytree Models
In the context of graphical causal discovery, we adapt the versatile framework of linear non-Gaussian acyclic models (LiNGAMs) to propose new algorithms to efficiently learn graphs that are polytrees. Our approach combines the Chow--Liu algorithm, which first learns the undirected tree structure, with novel schemes to orient the edges. The orientation schemes assess algebraic relations among moments of the data-generating distribution and are computationally inexpensive. We establish high-dimensional consistency results for our approach and compare different algorithmic versions in numerical experiments
The qT subtraction method: electroweak corrections and power suppressed contributions
Building upon the formulation of transverse-momentum resummation for heavy-quark hadroproduction, we present the first application of the qT subtraction formalism to the computation of electroweak corrections to massive lepton pairs through the Drell–Yan mechanism. We then study the power suppressed contributions to the qT subtraction formula in the parameter rcut, defined as the minimum transverse momentum of the lepton pair normalised to its invariant mass. We analytically compute the leading power correction from initial and final-state radiation to the inclusive cross section. In the case of initial-state radiation the power correction is quadratic in rcut and our analytic result is consistent with results previously obtained in the literature. Final-state radiation produces linear contributions in rcut that may challenge the efficiency of the qT subtraction procedure. We explicitly compute the linear power correction in the case of the inclusive cross section and we discuss the extension of our calculation to differential distributions
Selective asymmetry of ocular vestibular-evoked myogenic potential in patients with acute utricular macula loss
OBJECTIVES: We retrospectively evaluated a chart review of 3,525 patients evaluated for any acute disturbance. A total of 1,504 patients with acute vestibular syndrome (AVS) received an instrumental vestibular assessment within 72 h from the onset of the symptoms evaluated using simultaneously a combination of ocular vestibular-evoked myogenic potential (oVEMPs), cervical vestibular-evoked myogenic potential (cVEMPs), video head-impulse test (vHIT), and subjective visual vertical (SVV) were included in this study. MATERIALS and METHODS: A total of 41 patients with AVS that showed a normal horizontal canal function tested with vHIT, a normal cVEMP function, unilaterally reduced or absent oVEMP n10, and an altered SVV were enrolled. RESULTS: We found that although these patients referred acute vertigo and presented spontaneous nystagmus, they showed physiological values of vHIT and a normal saccular function, as shown by symmetrical cVEMPs. CONCLUSION: Our findings support the hypothesis that a percentage of patients evaluated during an AVS using an instrumental vestibular assessment could present selective utricular macula dysfunction
Effect of affective priming on prosocial orientation through mobile application: Differences between digital immigrants and natives
Digital revolution has drastically changed people’s lives in the last three decades inspiring scholars to deepen the role of technologies in thinking and information processing (Baranyi et al., 2015). Prensky (2001) has developed the notion of digital generation, differentiating between natives and immigrants. Digital natives are characterised by their highly automatic and quick response in hyper-textual environment. Digital immigrants are characterised by their main focus on textual elements and a greater proneness to reflection. The main goal of the present research is to investigate the effect of affective priming on prosocial orientation in natives and immigrants by using a mobile application. A quasi-experimental study has been conducted to test whether and how the manipulation of the priming, through positively and negatively connoted images, influences prosocial orientation. The results attested that negative affective priming elicited by app influences negatively prosocial orientation, while positive affective priming influences it positively prosocial orientation. However, this effect is true mainly for digital natives. Overall, findings underline the relevance of taking into account the effects of affective priming in technological environment, especially in the case of digital natives
Members of the zinc finger protein gene family sharing a conserved N-terminal module
We report the isolation of human members of a subfamily of structurally related finger protein genes. These potentially encode polypeptides containing finger motifs of the Krüppel type at the C-terminus, and a conserved amino acid module at the N-terminus; because of its invariant location the latter is referred to as finger preceding box (FPB). The FPB, detected also in previously described finger proteins from human, mouse and Xenopus, extends over approximately 65 amino acids and appears to be composed of two contiguous modules: FPB-A (residues 1-42) and FPB-B (residues 43-65). The latter is absent in some of the members analyzed. Elements A and B and the zinc finger domain are encoded by separate exons in the ZNF2 gene, a human member of this sub-family. The positioning of introns within this gene is remarkable. One intron flanks and a second interrupts the first codon of the FPB-A and FPB-B modules, respectively. A third intron occurs a few nucleotides downstream of FPB-B marking its separation from the remainder of the coding sequences. This organization, together with the absence of FPB-B in some cDNAs, supports the hypothesis that mRNAs encoding polypeptides that include one, both or none of the FPB-A and FPB-B modules may be assembled through alternative splicing pathways. Northern analyses showed that members of his sub-family are expressed as multiple transcripts in several cell lines. The sequences of distinct cDNAs homologous to the ZNF2 gene indicate that alternative splicing events adjoin either coding or non oding xons to the FPB sequences. © 1991 Oxford University Press
Self-efficacy configurations and wellbeing in the academic context: A person-centred approach
The aim of the present study was to identify self-efficacy configurations in different domains (i.e., emotional, social, and self-regulated learning) in a sample of university students using a person-centred approach. Results from a two-cohort sample (N = 1650) assessed at the beginning of their first year supported a 4-cluster solution: 1) Highly Self-Efficacious students, with high levels of self-efficacy in all domains; 2) Low Self-Efficacious students, with low levels of self-efficacy in all domains; 3) Learning and Socially Self-Efficacious students, with a medium-high level of self-regulated learning, medium level of social, and medium-low level of emotional self-efficacies; and 4) Emotionally Self-Efficacious students, with a medium-high level of emotional, medium-low level of social, and low level of self-regulated learning self-efficacies. The association of these configurations with wellbeing indicators, concurrently and one year later, provides support for the validity of the cluster solution. Specifically, by adopting the informative hypothesis testing approach, results showed that the first and second groups have the best and the worst wellbeing levels, respectively. Furthermore, whereas the other two groups did not differ with respect to depression, Learning and Socially Self-Efficacious students have higher life satisfaction than the last group. These results were confirmed both concurrently and over time
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