D' Production in Heavy Ion Collisions

The production of d' dibaryons in heavy ion collisions due to the elementary process NN -> d' + pion is considered. The cross section NN -> d' + pion is estimated using the vacuum d' width = 0.5 MeV extracted from data on the double charge exchange reactions on nuclei. The d' production rate per single collision of heavy ions is estimated at an incident beam energy of 1 A GeV within the framework of the Quantum Molecular Dynamics transport model. We suggest to analyse the invariant mass spectrum of the NN + pion system in order to search for an abundance of events with the invariant mass of the d' dibaryon. The d' peak is found to exceed the statistical fluctuations of the background at a level of 6 standard deviations for 2 10^5 A central collisions of heavy ions with the atomic number A.Comment: 29 pages including 7 figures, REVTe

Finite nuclear size effect on Lamb shift of s1/2, p1/2, and p3/2 atomic states

We consider one-loop self-energy and vacuum polarization radiative corrections to the shift of atomic energy level due to finite nuclear size. Analytic expressions for vacuum polarization corrections are derived. For the self-energy of p1/2 and p3/2 states in addition to already known terms we derive next-to-leading nonlogarithmic Z\alpha-terms. Together with contributions obtained earlier the terms derived in the present work give explicit analytic expressions for s1/2 and p1/2 corrections which agree with results of previous numerical calculations up to Z=100 (Z is the nuclear charge number). We also show that the finite nuclear size radiative correction for a p3/2 state is not small compared to the similar correction for a p1/2 state at least for small Z.Comment: 12 pages, 7 figure

Complete Break Up of Ortho Positronium (Ps)- Hydrogenic ion System

The dynamics of the complete breakup process in an Ortho Ps - He+ system including electron loss to the continuum (ELC) is studied where both the projectile and the target get ionized. The process is essentially a four body problem and the present model takes account of the two centre effect on the electron ejected from the Ps atom which is crucial for a proper description of the ELC phenomena. The calculations are performed in the framework of Coulomb Distorted Eikonal Approximation. The exchange effect between the target and the projectile electron is taken into account in a consistent manner. The proper asymptotic 3-body boundary condition for this ionization process is also satisfied in the present model. A distinct broad ELC peak is noted in the fully differential cross sections (5DCS) for the Ps electron corroborating qualitatively the experiment for the Ps - He system. Both the dynamics of the ELC from the Ps and the ejected electron from the target He+ in the FDCS are studied using coplanar geometry. Interesting features are noted in the FDCS for both the electrons belonging to the target and the projectile.Comment: 14 pages,7 figure

Delay in gallbladder emptying during the perimenopausal period

A pilot study has ascribed an important role in gallbladder motility and emptying to the perimenopausal period. To assess the effect of this period on gallbladder emptying and cholelithogenesis, 25 women in the perimenopausal period without gallbladder disease were submitted to cholangiography and two ultrasound exams. The time for gallbladder emptying and the presence of cholelithiasis were assessed. All patients presented a delay in gallbladder emptying with no relationship to the pre- or postmenopausal period. This finding was not related to lithogenesis. Gallbladder emptying time is longer during the perimenopausal period

Use of the Mini Nutritional Assessment to detect frailty in hospitalised older people

ObjectivesThe aims of this study were to: (1) determine the prevalence of undernutrition and frailty in hospitalised elderly patients and (2) evaluate the efficacy of both the Mini-Nutritional Assessment (MNA) screening tool and the MNA short form (MNA-SF) in identifying frailty.Setting and participantsA convenient sample of 100 consecutive patients (75.0 % female) admitted to the Geriatric Evaluation and Management Unit (GEMU) at The Queen Elizabeth Hospital in South Australia.MeasurementsFrailty status was determined using Fried's frailty criteria and nutritional status by the MNA and MNA-SF. Optimal cut-off scores to predict frailty were determined by Youden's Index, Receiver Operator Curves (ROC) and area under curve (AUC).ResultsUndernutrition was common. Using the MNA, 40.0% of patients were malnourished and 44.0% were at risk of malnutrition. By Fried's classification, 66.0 % were frail, 30.0 % were pre-frail and 4.0 % robust. The MNA had a specificity of 0.912 and a sensitivity of 0.516 in predicting frailty using the recommended cut-off for malnourishment (ConclusionThe quickly and easily administered MNA-SF appears to be a good tool for predicting both under-nutrition and frailty in elderly hospitalised people. Further studies would show whether the MNA-SF could also detect frailty in other populations of older people.E. Dent, R. Visvanathan, C. Piantadosi, I. Chapma