Parton Distributions in the Valon Model

The parton distribution functions determined by CTEQ at low $Q^2$ are used as inputs to test the validity of the valon model. The valon distributions in a nucleon are first found to be nearly $Q$ independent. The parton distribution in a valon are shown to be consistent with being universal, independent of the valon type. The momentum fractions of the partons in the valon add up separately to one. These properties affirm the validity of the valon model. The various distributions are parameterized for convenient application of the model.Comment: 9 pages + 9 figures in ep

Cultural Perspective on Parenting, Trait Emotional Intelligence and Mental Health in Taiwanese Children

The current study aims to clarify the associations as well as the pathways through which parenting and children's emotional intelligence (EI) may influence children's mental health with a cross-sectional sample of 675 school pupils (fourth grade, mean age = 10.4 years, 310 boy, 356 girls and 9 unidentified) in Taiwan. Hierarchical regression and path analyses were used to examine the relationships between parenting styles, children's trait EI, and their psychological symptoms, with children's psychological symptoms as the dependent variable. The results showed that authoritative parenting was positively associated with children‟s trait EI, which in turn had a negative effect on children‟s psychological symptoms, whereas authoritarian and Chinese-specific parenting styles had direct negative effect on children‟s psychological symptoms. These findings shed light on the pathways of the interrelations between different parenting styles, children's trait EI, and psychological symptoms, providing theoretical as well as practical implications for children's emotional development and mental health

Non-equilibrium initial conditions from pQCD for RHIC and LHC

We calculate the initial non-equilibrium conditions from perturbative QCD (pQCD) within Glauber multiple scattering theory for $\sqrt s =200$ AGeV and $\sqrt s =5.5$ ATeV. At the soon available collider energies one will particularly test the small $x$ region of the parton distributions entering the cross sections. Therefore shadowing effects, previously more or less unimportant, will lead to new effects on variables such as particle multiplicities $dN/dy$, transverse energy production $d\bar{E}_T/dy$, and the initial temperature $T_i$. In this paper we will have a closer look on the effects of shadowing by employing different parametrizations for the shadowing effect for valence quarks, sea quarks and gluons. Since the cross sections at midrapidity are dominated by processes involving gluons the amount of their depletion is particularly important. We will therefore have a closer look on the results for $dN/dy$, $d\bar{E}_T/dy$, and $T_i$ by using two different gluon shadowing ratios, differing strongly in size. As a matter of fact, the calculated quantities differ significantly.Comment: typo in ref's removed, ack's added, no change in result

Internet Addiction: A Closer Look at Multidimensional Parenting Practices and Child Mental Health

This study aimed to examine how both psychosocial variables (authoritative, authoritarian, and shaming, and parent-child relationships) and psychological symptoms were associated with Internet addiction, while controlling for the sociodemographic variable (child gender). A national proportionately stratified random sample of 6,233 fourth-grade primary school students in Taiwan participated in the study. Hierarchical regression models were performed to test the research hypotheses. The results show that psychological symptoms, authoritarian parenting, and shaming were positively associated with Internet addiction, whereas authoritative parenting and positive parent-child relationship were negatively associated with Internet addiction. Girls had lower levels of Internet addiction than boys. In conclusion, this study demonstrates the direct effects of child mental health status, multidimensional parenting practices, and family relationship on Internet addiction in children, and the importance of early individual- and family-based prevention and intervention in addressing related public health concerns of Internet addiction in children. The cultural perspectives of parenting and implications of these findings are discussed

Low Q2Q^2 wave-functions of pions and kaons and their parton distribution functions

We study the low $Q^2$ wave-functions of pions and kaons as an expansion in terms of hadron-like Fock state fluctuations. In this formalism, pion and kaon wave-functions are related one another. Consequently, the knowledge of the pion structure allows the determination of parton distributions in kaons. In addition, we show that the intrinsic (low $Q^2$) sea of pions and kaons are different due to their different valence quark structure. Finally, we analize the feasibility of a method to extract kaon's parton distribution functions within this approach and compare with available experimental data.Comment: 13 pages, 3 postscript figures include

The bard−uˉbar{d} - \bar{u} asymmetry of the proton in a Pion Cloud Model approach

We study the $bar{d} - \bar{u}$ asymmetry of the proton in a model approach in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that the asymmetry of the proton is consistently described by including only nucleon fluctuations to $|\pi N>$ and $|\pi \Delta>$ bound states. Predictions of the model closely agree with the recent experimental data of the E866/NuSea Collaboration.Comment: Final version. To appear in Phys. Rev.

Light flavor asymmetry of nucleon sea

The light flavor antiquark distributions of the nucleon sea are calculated in the effective chiral quark model and compared with experimental results. The contributions of the flavor-symmetric sea-quark distributions and the nuclear EMC effect are taken into account to obtain the ratio of Drell-Yan cross sections $\sigma^{\mathrm{pD}}/2\sigma^{\mathrm{pp}}$, which can match well with the results measured in the FermiLab E866/NuSea experiment. The calculated results also match the measured $\bar{d}(x)-\bar{u}(x)$ from different experiments, but unmatch the behavior of $\bar{d}(x)/\bar{u}(x)$ derived indirectly from the measurable quantity $\sigma^{\mathrm{pD}}/2\sigma^{\mathrm{pp}}$ by the FermiLab E866/NuSea Collaboration at large $x$. We suggest to measure again $\bar{d}(x)/\bar{u}(x)$ at large $x$ from precision experiments with careful experimental data treatment. We also propose an alternative procedure for experimental data treatment.Comment: 10 pages, 8 figures, final version to appear in EPJ