Constraints on the R-parity- and Lepton-Flavor-Violating Couplings from B0 Decats to Two Charged Leptons

We derive the upper bounds on certain products of R-parity- and lepton-flavor-violating couplings from the decays of the neutral $B$ meson into two charged leptons. These modes of $B^0$ decays can constrain the product combinations of the couplings with one or more heavy generation indices. We find that most of these bounds are stronger than the previous ones.Comment: Table is changed; version to appear in Phys. Rev.

Recalculation of QCD Corrections to b→sγb \to s \gamma Decay

We give a more complete calculation of $b \to s\gamma$ decay, including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. We have included the full set of dimension-6 operators and corrected numerical mistakes of anomalous dimensions in a previous paper\cite{Cho}. Comparing with the calculations without QCD running from $m_{top}$ to $M_W$\cite{Mis}, the inclusive decay rate is found to be enhanced. At $m_t=150$GeV, it results in 12\% enhancement, and for $m_t=250$GeV, 15\% is found. The total QCD effect makes an enhanced factor of 4.2 at $m_t=150$GeV, and 3.2 for $m_t=250$GeV.Comment: 16 pages, 7 figures (uuencoded ps files), Changes of description. To appear in Phys. Rev.

The Assessment of Reliability Under Range Restriction: A Comparison of α, ω, and Test–Retest Reliability for Dichotomous Data

Though much research and attention has been directed at assessing the correlation coefficient under range restriction, the assessment of reliability under range restriction has been largely ignored. This article uses item response theory to simulate dichotomous item-level data to assess the robustness of KR-20 (α), ω, and test–retest under varying selection ratios. These estimators, both corrected and uncorrected for range restriction, were compared in terms of both bias and precision. Test–retest reliability was usually the best estimator of reliability across a variety of conditions. Only under indirect range restriction did KR-20 and ω performed well. All estimators suffered imprecision as a function of range restriction, above and beyond the reduction in sample size. Based on the results, a set of recommendations are proposed.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Conceptual learning : the priority for higher education

The common sense notion of learning as the all-pervasive acquisition of new behaviour and knowledge, made vivid by experience, is an incomplete characterisation, because it assumes that the learning of behaviour and the learning of knowledge are indistinguishable, and that acquisition constitutes learning without reference to transfer. A psychological level of analysis is used to argue that conceptual learning should have priority in higher education

Analysis of Charge Asymmetry in Rare Dilepton BB Decays

We analyze forward-backward charge asymmetry of the lepton production in rare decays $B\rightarrow X_s l^+l^-$ and $B\rightarrow K^* l^+l^-$, including vector-resonance effects. Certain regions of phase space, in which the asymmetry is sensitive to individual short-distance coefficients, are pointed out. In particular, we suggest a method to test the coupling of the leptonic axial vector current to the left-handed quark current experimentally.Comment: 27 pages, 4 figures available up to requiremen

b→sγb \to s \gamma Decay and Right-handed Top-bottom Charged Current

We introduce an anomalous top quark coupling (right-handed current) into Standard Model Lagrangian. Based on this, a more complete calculation of $b \to s\gamma$ decay including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$ is given. The inclusive decay rate is found to be suppressed comparing with the case without QCD running from $m_t$ to $M_W$ except at the time of small values of $|f_R^{tb}|$. e.g. when $f_R^{tb}=-0.08$, it is only $1/10$ of the value given before. As $|f_R^{tb}|$ goes smaller, this contribution is an enhancement like standard model case. From the newly experiment of CLEO Collaboration, strict restrictions to parameters of this top-bottom quark coupling are found.Comment: 20 Pages, 2 figures( ps file uuencoded)

Large-basis shell-model calculation of 10C->10B Fermi matrix element

We use a $4\hbar\Omega$ shell-model calculation with a two-body effective interaction derived microscopically from the Reid93 potential to calculate the isospin-mixing correction for the 10C->10B superallowed Fermi transition. The effective interaction takes into account the Coulomb potential as well as the charge dependence of T=1 partial waves. Our results suggest the isospin- mixing correction $\delta_{C}\approx 0.1$, which is compatible with previous calculations. The correction obtained in those calculations, performed in a $0\hbar\Omega$ space, was dominated by deviation from unity of the radial overlap between the converted proton and the corresponding neutron. In the present calculation this effect is accommodated by the large model space. The obtained $\delta_{C}$ correction is about a factor of four too small to obtain unitarity of the Cabibbo-Kobayashi-Maskawa matrix with the present experimental data.Comment: 14 pages. REVTEX. 3 PostScript figure

Flavor Symmetries and The Problem of Squark Degeneracy

If supersymmetry exists at low energies, it is necessary to understand why the squark spectrum exhibits sufficient degeneracy to suppress flavor changing neutral currents. In this note, we point out that gauged horizontal symmetries can yield realistic quark mass matrices, while at the same time giving just barely enough squark degeneracy to account for neutral $K$-meson phenomenology. This approach suggests likely patterns for squark masses, and indicates that there could be significant supersymmetric contributions to $B-\bar{B}$ and $D-\bar{D}$ mixing and CP violation in the $K$ and $B$ systems.Comment: preprint SCIPP 93/04,SLAC-PUB-6147, 14 pages, 4 tables included; uses macro package TABLES.TEX and phyzzx forma

A lattice study of the exclusive B→K∗γB \to K^* \gamma decay amplitude, using the Clover action at β=6.0\beta=6.0

We present the results of a numerical calculation of the $B\to K^* \gamma$ form factors. The results have been obtained by studying the relevant correlation functions at $\beta=6.0$, on an $18^3 \times 64$ lattice, using the ${\rm O(a)}$-improved fermion action, in the quenched approximation. From the study of the matrix element $$ we have obtained the form factor $T_1(0)$ which controls the exclusive decay rate. The results are compared with the recent results from CLEO. We also discuss the compatibility between the scaling laws predicted by the Heavy Quark Effective Theory (HQET) and pole dominance, by studying the mass- and $q^2$-dependence of the form factors. From our analysis, it appears that the form factors follow a mass behaviour compatible with the predictions of the HQET and that the $q^2$-dependence of $T_2$ is weaker than would be predicted by pole dominance.Comment: 17 pages, LaTeX + epsf.sty. Uuencoded, compressed, tar archive including the text and one postscript figur

Prevalence and predictors of video game addiction: a study based on a national representative sample of gamers

Video gaming has become a popular leisure activity in many parts of the world, and an increasing number of empirical studies examine the small minority that appears to develop problems as a result of excessive gaming. This study investigated prevalence rates and predictors of video game addiction in a sample of gamers, randomly selected from the National Population Registry of Norway (N =3389). Results showed there were 1.4 % addicted gamers, 7.3 % problem gamers, 3.9 % engaged gamers, and 87.4 % normal gamers. Gender (being male) and age group (being young) were positively associated with addicted-, problem-, and engaged gamers. Place of birth (Africa, Asia, South- and Middle America) were positively associated with addicted- and problem gamers. Video game addiction was negatively associated with conscientiousness and positively associated with neuroticism. Poor psychosomatic health was positively associated with problem- and engaged gaming. These factors provide insight into the field of video game addiction, and may help to provide guidance as to how individuals that are at risk of becoming addicted gamers can be identified