Pion Compton scattering and bremsstrahlung

The pion-polarizability functions are structure functions of pion-Compton scattering. They can be assessed in high-energy pion-nucleus bremsstrahlung reactions, $\pi^- +A\to\pi^- +\gamma +A$. We present numerical expectations for pion-nucleus bremsstrahlung cross sections in the Coulomb region, i.e. the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. We investigate the prospects of measuring the polarizability functions for pion-Compton c.m. energies from threshold up to 1 GeV. A meson-exchange model is used for the pion-Compton amplitude.Comment: 20 pages, 11 figure

Hard pion bremsstrahlung in the Coulomb region

Hard high-energy pion-nucleus bremsstrahlung, $\pi^- +A\to\pi^- +\gamma +A$, is studied in the Coulomb region, i.e. the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. Special attention is focussed on the possibility of measuring the pion polarizability in such reactions. We study the sensitivity to the structure of the underlying the pion-Compton amplitude through a model with $\sigma$, $\rho$, and a_1 exchanges. It is found that the effective energy in the virtual pion-Compton scattering is often so large that the threshold approximation does not apply.Comment: 18 pages, 5 figure

Coulomb-nuclear interference in pion-nucleus bremsstrahlung

Pion-nucleus bremsstrahlung offers a possibility of measuring the structure functions of pion-Compton scattering from a study of the small-momentum-transfer region where the bremsstrahlung reaction is dominated by the single-photon-exchange mechanism. The corresponding cross-section distribution is characterized by a sharp peak at small momentum transfers. But there is also a hadronic contribution which is smooth and constitutes an undesired background. In this communication the modification of the single-photon exchange amplitude by multiple-Coulomb scattering is investigated as well as the Coulomb-nuclear interference term.Comment: 21 pages, 5 figures. Eqs.(51,52) corrected; some new figure

Can diabetes medication be reduced in elderly patients? : An observational study of diabetes drug withdrawal in nursing home patients with tight glycaemic control

Aim: To explore the feasibility of withdrawal of diabetes medication in elderly patients with HbA1c £ 6.0%. Methods: HbA1c was measured in 98 patients with known diabetes in 17 nursing homes in Sweden. 32 subjects with HbA1c £ 6.0% participated in the drug withdrawal study. After measuring plasma glucose on three consecutive days, diabetes drugs were reduced, i.e. complete withdrawal of oral anti-diabetic drugs (OADs), complete insulin withdrawal when doses were £ 20 units/day and reduced by half in patients on more than 20 units/day. Results: We identified 31 episodes of plasma glucose £ 4.4 mmol/l, most of them nocturnal (n=17). Mean HbA1c was 5.2 % ± 0.4 compared to 7.1 % ± 1.6 in the non-intervention group. Three months after the diabetes drug discontinuation, 24 patients (75%) remained in the intervention group and mean HbA1c was then 5.8 %. ± 0.9. Six months after baseline investigation mean HbA1c in the intervention group was 5.8 % ± 1.1 compared with 6.6 % ± 1.4 in the non-intervention group. Conclusions: Hypoglycaemic events are common among elderly patients with type 2 diabetes. The withdrawal of diabetes medication in elderly with tight glycaemic control is safe and may decrease the risk for hypoglycaemia.Original Publication: Peter Sjöblom, Anders Tengblad, Ulla-Britt Löfgren, Christina Lannering, Niklas Anderberg, Ulf Rosenqvist, Sigvard Mölstad and Carl J Östgren, Can diabetes medication be reduced in elderly patients?: An observational study of diabetes drug withdrawal in nursing home patients with tight glycaemic control, 2008, Diabetes Research and Clinical Practice, (82), 2, 197-202. http://dx.doi.org/10.1016/j.diabres.2008.08.014 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/</p