The four-loop β-function of quantum chromodynamics is calculated and agreement is found with the previous result. The anomalous dimensions of the quark-gluon vertex, and quark, gluon and ghost fields are given for a general compact simple Lie group.

We relate leptogenesis in a class of theories to low-energy experimental observables: quark and lepton masses and mixings. With reasonable assumptions motivated by grand unification, one can show that the CP-asymmetry parameter takes a universal form. Furthermore the dilution mass is related to the light neutrino masses. Overall, these models offer a natural explanation for a lepton asymmetry i...

Pure leptonic radiative decays of heavy-light mesons are calculated using a very simple non-relativistic model. Dominant contribution originates from photon emission from light initial quark. We find BR(B ± → ℓνγ) ∼ 3.5 × 10 −6 and BR(D s → ℓνγ) ∼ 1.7 × 10 −4. The importance of these reactions to clarify the dynamics of the annihilation graph is emphasized.

In our model with a Standard Model gauge group extended with a baryon number minus lepton number charge for each family of quarks and leptons, we calculate the baryon number relative to entropy produced in early Big Bang by the FukugitaYanagida mechanism. With the parameters, i.e., the Higgs VEVs already fitted in a very successful way to quark and lepton masses and mixing angles we obtain the ...

The motion of quark is studied in a confining bag having central color field. The Dirac equation is solved for a quark in such bag and its energy spectrum is found. It is pointed out the possibility to take into account an interaction of constituent quark with the gluon condensation as the interaction with the color background.

We study a parton shower description, based on a dipole picture, of the final state in electron-positron annihilation. In such a shower, the distribution function describing the inclusive probability to find a quark with a given energy depends on the shower evolution time. Starting from the exclusive evolution equation for the shower, we derive an equation for the evolution of the inclusive qua...

We argue that there is strong experimental evidence in the data of band c-decays that the pattern of power suppressed corrections predicted by the short distance expansion, the heavy quark effective theory and the assumption of local duality is not correct for the non-leptonic inclusive widths. The data indicate instead the presence of 1/m corrections that should be absent in the above theoreti...

STUDY OBJECTIVE The primary aim of the research described in this paper was to ascertain whether inclusion of a self administered questionnaire with the usual invitation to routine breast screening affected screening uptake. Secondary aims included establishing appropriate questionnaire distribution and collection methods within the framework of the National Health Service Breast Screening Prog...

Objective. To understand older primary care patients' perceptions of the risks and benefits of dementia screening and to measure the association between attitudes and screening behaviors. Methods. Eligible patients completed the Perceptions Regarding Investigational Screening for Memory in Primary Care (PRISM-PC) questionnaire and then were asked to undergo dementia screening by a telephone scr...

OBJECTIVE The aims of the study were to identify the characteristics of the dieters most at risk of subsequently developing an eating disorder and to evaluate the feasibility of using a brief questionnaire to identify such dieters in advance. METHOD A general population cohort of 2,992 young women who were dieting was identified. On four occasions over the subsequent 2 years, this cohort was ...