Enhancement of preasymptotic effects in inclusive beauty decays

We extend Voloshin's recent analysis of charmed and beauty hyperon decays based on SU(3) symmetry and heavy quark effective theory, by introducing a rather moderate model-dependence, in order to obtain more predictive power, e.g. the values of lifetimes of the (\Lambda_{b},\Xi_{b}) hyperon triplet and the lifetime of \Omega_{b}. In this way we obtain an improvement of the ratio \tau(\Lambda_{b})/\tau(B_{d}^{0}) \sim 0.9 and the hierarchy of lifetimes \tau(\Lambda_{b}) \simeq \tau(\Xi_{b}^{0}) < \tau(\Xi_{b}^{-}) < \tau(\Omega_{b}) with lifetimes of \Xi_{b}^{-} and \Omega_{b} exceeding the lifetime of \Lambda_{b} by 22% and 35%, respectively.Comment: Latex2e, 12 pages, 3 eps figures include

Cabibbo suppressed decays and the Ξc+\Xi_{c}^{+} lifetime

The problem of the $\Xi_{c}^{+}$ lifetime is considered in the framework of {\em Heavy-Quark Expansion} and $SU(3)_{flavor}$ symmetry. The lifetime of $\Xi_{c}^{+}$ is expressed in terms of measurable inclusive quantities of the other two charmed baryons belonging to the same $SU(3)_{flavor}$ multiplet in a model-independent way. In such a treatment, inclusive decay rates of singly Cabibbo suppressed decay modes have a prominent role. An analogous approach is applied to the multiplet of charmed mesons yielding interesting predictions on $D_{s}^{+}$ properties. The results obtained indicate that a more precise measurement of inclusive decay quantities of some charmed hadrons (such as $\Lambda_{c}^{+}$) that are more amenable to experiment can contribute significantly to our understanding of decay properties of other charmed hadrons (such as $\Xi_{c}^{+}$) where discrepancies or ambiguities exist.Comment: 9 pages, revtex4; certain improvements in text as suggested by the referee, acknowledgement changed; version to appear in Phys. Rev.

Inclusive Charmed-Baryon Decays and Lifetimes

We have quantitatively reanalyzed the inclusive charmed-baryon decays. New ingredients are the Voloshin preasymptotic effects in semileptonic decays and the Cabibbo-subleading contributions to both semileptonic and nonleptonic decays. It has been found that the Cabbibo-subleading Voloshin contribution essentially improves the theoretical semileptonic branching ratio of $\Lambda_c^{+}$, in agreement with experiment. The semileptonic branching ratios for $\Xi_c^{+}$ and $\Omega_c^{0}$ are found to be large, i.e., of the order of 20%. The lifetimes hierarchy is in a good qualitative and even quantitative agreement with experiment except for the $\Xi_c^{+}$ lifetime, which is somewhat smaller than the experimental value. Future measurements, especially measurements of the semileptonic branching ratios for $\Omega_c^{0}$, $\Xi_c^{+}$ and $\Xi_c^{0}$ should be decisive for the check of this approach.Comment: 13 pages, Latex, 3 figures included, shortened version, to appear in Z.Phys.

Preasymptotic effects in beauty decays

Large preasymptotic effects in beauty decays have been found using heavy-quark and SU(3) symmetry, as well as experimental data on charmed hyperons. Contrary to rather uniform beauty-meson lifetimes, a much larger spread of beauty-baryon lifetimes is predicted. However, it is highly unlikely that, theoretically, the $\tau(\Lambda_b)/\tau(B_d^0)$ ratio, which at present deviates more than $1\sigma$ from the experimental result, can be lowered below 0.9.Comment: 6 pages, talk given by B. Melic at The 3rd International Conference on B Physics and CP Violation, Taipei, Taiwan, December 3-7, 1999, to appear in the Proceedings, two figures adde

Renormalization-group running cosmologies and the generalized second law

We explore some thermodynamical consequences of accelerated universes driven by a running cosmological constant (CC) from the renormalization group (RG). Application of the generalized second law (GSL) of gravitational thermodynamics to a framework where the running of the CC goes at the expense of energy transfer between vacuum and matter, strongly restricts the mass spectrum of a (hypothetical) theory controlling the CC running. We find that quantum effects driving the running of the CC should be dominated by a trans-planckian mass field, in marked contrast with the GUT-scale upper mass bound obtained by analyzing density perturbations for the running CC. The model shows compliance with the holographic principle.Comment: 8 pages, final version to appear in Phys. Lett.

Inclusive decays and lifetimes of doubly charmed baryons

The analysis of singly charmed hadrons has been extended to the case of doubly charmed baryons, $\Xi_{cc}^{++}$, $\Xi_{cc}^{+}$ and $\Omega_{cc}^{+}$. Doubly charmed baryons are described as a system containing a heavy $cc$-diquark and a light quark, similarly as in a heavy-light meson. This leads to preasymptotic effects in semileptonic and nonleptonic decays which are essentially proportional to the meson wave function. Interplay between preasymptotic effects in semileptonic and/or nonleptonic decay rates leads to very clear predictions for semileptonic branching ratios and lifetimes of doubly charmed baryons.Comment: 14 pages latex file, 4 figures, 1 tabl

Denture Repairs in Different Regions of Croatia in Relation to Prosthodontic Teams

The purpose of this paper is to evaluate the incidence of denture repairs in different districts of Croatia through the year of 2002. and to analyse the percentage of different repairs (relinings, simple repairs up to 2 elements and complicated repairs-more than 2 elements) in relation to prosthodontic teams. Data on the number of dentures, and the number and types of denture repairs delivered in the Croatian regions of Zagreb, Rijeka, Split and Karlovac were obtained from the Croatian Insitute for Health Insurance for the whole of the year 2002. Information of the number of prosthodontic teams operating in those regions was also obtained. Proportionally more denture repairs were carried out in Karlovac (18%) than Split (5%). The smallest percantage of dentures that required relining was registered in Split and the highest in Rijeka (2=36.7, p<0.01). The smallest percentage of simple repairs was registered in Rijeka and the highest in Split (2=24.3, p<0.01).The smallest percentage of complicated repairs was registered in Split and the highest in Karlovac. In each region the proportion of denture repairs and types of repairs were correlated with a number of prosthodontic teams in that region. Karlovac had the smallest percentage of specialistic prosthodontic teams and the highest rate of denture repairs

Prognostic Significance of Alkaline Phosphatase Activity and Callus Volume in Operatively Treated Bone Fractures

Total and bone alkaline phosphatase are indicators of bone formation, a process essential in bone healing. The aim of this study was to assess the relationship of both total and bone alkaline phosphatase with the course and features of healing in surgically treated long bone fractures as compared to the callus volume. In this study, total and bone alkaline phosphatase levels and the callus volume were measured in two patients with long bone fractures. Fracture healing was rapid in one patient and slow in the other. Depending on the healing outcome, on day 7 an increase in the case of slow healing and a decrease in the case of rapid healing was noted for both total and bone alkaline phosphatase. In the case of slow healing, the callus volume was significant whereas in the case of rapid healing the callus was almost invisible on day 7. This result indicates a possible prognostic significance of aforementioned clinical biochemical and radiographic parameters in the monitoring of long bone fracture healing

Critical Infrastructures Protection in the City Region of Zagreb

This paper presents the review of the issue of critical infrastructure in the City of Zagreb and the role of the Emergency Management Office in the above themes. There will be described operations and analysis at the level of the Office in the segment of civil protection reaffirmation, ie. the training of its members, which should be a significant support to operational forces in the event of an accident or disaster during an earthquake, being the biggest threat to the City of Zagreb