Information content of the weak-charge form factor

Parity-violating electron scattering provides a model-independent determination of the nuclear weak-charge form factor that has widespread implications across such diverse areas as fundamental symmetries, nuclear structure, heavy-ion collisions, and neutron-star structure. We assess the impact of precise measurements of the weak-charge form factor of ${}^{48}$Ca and ${}^{208}$Pb on a variety of nuclear observables, such as the neutron skin and the electric-dipole polarizability. We use the nuclear Density Functional Theory with several accurately calibrated non-relativistic and relativistic energy density functionals. To assess the degree of correlation between nuclear observables and to explore systematic and statistical uncertainties on theoretical predictions, we employ the chi-square statistical covariance technique. We find a strong correlation between the weak-charge form factor and the neutron radius, that allows for an accurate determination of the neutron skin of neutron-rich nuclei. We determine the optimal range of the momentum transfer $q$ that maximizes the information content of the measured weak-charge form factor and quantify the uncertainties associated with the strange quark contribution. Moreover, we confirm the role of the electric-dipole polarizability as a strong isovector indicator. Accurate measurements of the weak-charge form factor of ${}^{48}$Ca and ${}^{208}$Pb will have a profound impact on many aspects of nuclear theory and hadronic measurements of neutron skins of exotic nuclei at radioactive-beam facilities.Comment: 10 pages, 4 figure

Sensitivity of the electric dipole polarizability to the neutron skin thickness in 208{}^{208}Pb

The static dipole polarizability, $\alpha_{\rm D}$, in ${}^{208}$Pb has been recently measured with high-resolution via proton inelastic scattering at the Research Center for Nuclear Physics (RCNP). This observable is thought to be intimately connected with the neutron skin thickness, $r_{\rm skin}$, of the same nucleus and, more fundamentally, it is believed to be associated with the density dependence of the nuclear symmetry energy. The impact of $r_{\rm skin}$ on $\alpha_{\rm D}$ in ${}^{208}$Pb is investigated and discussed on the basis of a large and representative set of relativistic and non-relativistic nuclear energy density functionals (EDF).Comment: Proceedings of NSD12, Opatija, Croatia, 9-13 July 201

Pygmies, Giants, and Skins

Understanding the equation of state (EOS) of neutron-rich matter is a central goal of nuclear physics that cuts across a variety of disciplines. Indeed, the limits of nuclear existence, the collision of energetic heavy ions, the structure of neutron stars, and the dynamics of core-collapse supernova all depend critically on the nuclear-matter EOS. In this contribution I focus on the EOS of cold baryonic matter with special emphasis on its impact on the structure, dynamics, and composition of neutron stars. In particular, I discuss how laboratory experiments on neutron skins as well as on Pygmy and Giant resonances can help us elucidate the structure of these fascinating objects.Comment: Invited Talk given at the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS

Electric dipole polarizability and the neutron skin

The recent high-resolution measurement of the electric dipole (E1) polarizability (alphad) in 208Pb [Phys. Rev. Lett. 107, 062502 (2011)] provides a unique constraint on the neutron-skin thickness of this nucleus. The neutron-skin thickness (rskin) of 208Pb is a quantity of critical importance for our understanding of a variety of nuclear and astrophysical phenomena. To assess the model dependence of the correlation between alphad and rskin, we carry out systematic calculations for 208Pb, 132Sn, and 48Ca based on the nuclear density functional theory (DFT) using both non-relativistic and relativistic energy density functionals (EDFs). Our analysis indicates that whereas individual models exhibit a linear dependence between alphad and rskin, this correlation is not universal when one combines predictions from a host of different models. By averaging over these model predictions, we provide estimates with associated systematic errors for rskin and alphad for the nuclei under consideration. We conclude that precise measurements of rskin in both 48Ca and 208Pb---combined with the recent measurement of alphad---should significantly constrain the isovector sector of the nuclear energy density functional.Comment: Manuscript contains 5 pages, 2 figures, and 1 table. Submitted to Physical Review Letter

Irbesartan for the treatment of hypertension in patients with the metabolic syndrome: A sub analysis of the Treat to Target post authorization survey. Prospective observational, two armed study in 14,200 patients

OBJECTIVES: The metabolic syndrome is a cluster of cardiovascular risk factors leading to an increased risk for the subsequent development of diabetes and cardiovascular morbidity and mortality. Blocking the renin-angiotensin system has been shown to prevent cardiovascular disease and delay the onset of diabetes. Irbesartan is an angiotensin receptor blocker (ARB) which has been shown to possess peroxisome proliferator-activated receptor gamma (PPARγ) activating properties, and to have a favorable metabolic profile. Current discussion is whether the addition of small doses of hydrochlorothiazide changes this profile. Therefore the efficacy, safety and metabolic profile of Irbesartan either as monotherapy or in combination therapy was assessed in patients with the metabolic syndrome in a large observational cohort in primary care. RESEARCH DESIGN AND METHODS: Multicenter, prospective, two-armed, post authorization study over 9 months in 14,200 patients with uncontrolled hypertension with and without the metabolic syndrome (doctors' diagnosis based on the Adult Treatment Panel III criteria 2001). Blood pressure was measured sphygmomanometrically and cardiovascular risk factors making up the criteria for the metabolic syndrome were assessed. MAIN OUTCOME MEASURES: Systolic (SBP) and diastolic (DBP) blood pressure reduction, – response, and – normalization (systolic and diastolic), changes in fasting glucose, waist circumference (abdominal obesity), serum triglycerides and HDL cholesterol as well as the proportion of patients fulfilling the criteria for the metabolic syndrome. Number and nature of adverse events (AEs). RESULTS: After 9 month the use of Irbesartan in monotherapy resulted in a significant reduction of blood pressure (SBP: -26.3 ± 10.1 mmHg/DBP-13.0 ± 6.6 mmHg, both p < 0.0001) in patients with the metabolic syndrome. This was accompanied by a reduction in cardiovascular risk factors: HDL cholesterol (+3.6 ± 7.2 mg/dl in men, +3.8 ± 6.5 mg/dl in women, both p < 0.0001), serum triglycerides (-28.6 ± 52.1 mg/dl, p < 0.0001), fasting blood glucose (-8.4 ± 25.1 mg/dl, p < 0.0001) and waist circumference (-2.4 ± 11.9 cm in men, -1.2 ± 14.2 in women, both p < 0.0001) were significantly improved. Irbesartan combination therapy (12.5 mg HCTZ) in patients with the metabolic syndrome: blood pressure reduction (SBP: -27.5 ± 10.1 mmHg/DBP: -14.1 ± 6.6 mmHg, both p < 0.0001), improvement in HDL cholesterol (+4.0 ± 6.8 mg/dl in men, +3.4 ± 6.8 in women, both p < 0.0001), triglycerides (-34.1 ± 52.6 mg/dl, p < 0.0001), fasting blood glucose (-10.0 ± 24.7, p < 0.0001) and waist circumference (-3.2 ± 12.7 cm in men, -1.7 ± 14.4 in women, both p < 0.0001). Tolerability was excellent: only 0.6% of patients experienced an AE. CONCLUSION: There was a significant improvement in blood pressure and metabolic risk factors as a result of Irbesartan treatment. There was no evidence of a difference between monotherapy and combination therapy with regard to the cardiovascular risk profile

Neutron-skin thickness of 208^{208}Pb, and symmetry-energy constraints from the study of the anti-analog giant dipole resonance

The $^{208}$Pb($p$,$n\gamma\bar p$) $^{207}$Pb reaction at a beam energy of 30 MeV has been used to excite the anti-analog of the giant dipole resonance (AGDR) and to measure its $\gamma$-decay to the isobaric analog state in coincidence with proton decay of IAS. The energy of the transition has also been calculated with the self-consistent relativistic random-phase approximation (RRPA), and found to be linearly correlated to the predicted value of the neutron-skin thickness ($\Delta R_{pn}$). By comparing the theoretical results with the measured transition energy, the value of 0.190 $\pm$ 0.028 fm has been determined for $\Delta R_{pn}$ of $^{208}$Pb, in agreement with previous experimental results. The AGDR excitation energy has also been used to calculate the symmetry energy at saturation ($J=32.7 \pm 0.6$ MeV) and the slope of the symmetry energy ($L=49.7 \pm 4.4$ MeV), resulting in more stringent constraints than most of the previous studies.Comment: 6 pages, 5 figures. arXiv admin note: text overlap with arXiv:1205.232

First-line antihypertensive treatment in patients with pre-diabetes: Rationale, design and baseline results of the ADaPT investigation

<p>Abstract</p> <p>Background</p> <p>Recent clinical trials reported conflicting results on the reduction of new-onset diabetes using RAS blocking agents. Therefore the role of these agents in preventing diabetes is still not well defined. Ramipril is an ACE inhibitor (ACEi), that has been shown to reduce cardiovascular events in high risk patients and post-hoc analyses of the HOPE trial have provided evidence for its beneficial action in the prevention of diabetes.</p> <p>Methods</p> <p>The ADaPT investigation ("ACE inhibitor-based versus diuretic-based antihypertensive primary treatment in patients with pre-diabetes") is a 4-year open, prospective, parallel group phase IV study. It compares an antihypertensive treatment regimen based on ramipril versus a treatment based on diuretics or betablockers. The primary evaluation criterion is the first manifestation of type 2 diabetes. The study is conducted in primary care to allow the broadest possible application of its results. The present article provides an outline of the rationale, the design and baseline characteristics of AdaPT and compares these to previous studies including ASCOT-BLPA, VALUE and DREAM.</p> <p>Results</p> <p>Until March 2006 a total of 2,015 patients in 150 general practices (general physicians and internists) throughout Germany were enrolled. The average age of patients enrolled was 67.1 ± 10.3 years, with 47% being male and a BMI of 29.9 ± 5.0 kg/m². Dyslipidemia was present in 56.5%. 37.8% reported a family history of diabetes, 57.8% were previously diagnosed with hypertension (usually long standing). The HbA1c value at baseline was 5.6 %. Compared to the DREAM study patients were older, had more frequently hypertension and patients with cardiovascular disease were not excluded.</p> <p>Conclusion</p> <p>Comparing the ADaPT design and baseline data to previous randomized controlled trial it can be acknowledged that AdaPT included patients with a high risk for diabetes development. Results are expected to be available in 2010. Data will be highly valuable for clinical practice due to the observational study design.</p

Superallowed Fermi transitions in RPA with a relativistic point-coupling energy functional

The self-consistent random phase approximation (RPA) approach with the residual interaction derived from a relativistic point-coupling energy functional is applied to evaluate the isospin symmetry-breaking corrections {\delta}c for the 0+\to0+ superallowed Fermi transitions. With these {\delta}c values, together with the available experimental ft values and the improved radiative corrections, the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix is examined. Even with the consideration of uncertainty, the sum of squared top-row elements has been shown to deviate from the unitarity condition by 0.1% for all the employed relativistic energy functionals.Comment: 13 pages,2 figure

Isoscalar dipole coherence at low energies and forbidden E1 strength

In 16O and 40Ca an isoscalar, low-energy dipole transition (IS-LED) exhausting approximately 4% of the isoscalar dipole (ISD) energy-weighted sum rule is experimentally known, but conspicuously absent from recent theoretical investigations of ISD strength. The IS-LED mode coincides with the so-called isospin-forbidden E1 transition. We report that for N=Z nuclei up to 100Sn the fully self-consistent Random-Phase-Approximation with finite-range forces, phenomenological and realistic, yields a collective IS-LED mode, typically overestimating its excitation energy, but correctly describing its IS strength and electroexcitation form factor. The presence of E1 strength is solely due to the Coulomb interaction between the protons and the resulting isospin-symmetry breaking. The smallness of its value is related to the form of the transition density, due to translational invariance. The calculated values of E1 and ISD strength carried by the IS-LED depend on the effective interaction used. Attention is drawn to the possibility that in N-not-equal-Z nuclei this distinct mode of IS surface vibration can develop as such or mix strongly with skin modes and thus influence the pygmy dipole strength as well as the ISD strength function. In general, theoretical models currently in use may be unfit to predict its precise position and strength, if at all its existence.Comment: 9 pages, 6 figures, EPJA submitte

Ramipril-based versus diuretic-based antihypertensive primary treatment in patients with pre-diabetes (ADaPT) study

<p>Abstract</p> <p>Background</p> <p>Previous randomized controlled trials demonstrated a protective effect of renin angiotensin system blocking agents for the development of type-2 diabetes in patients with pre-diabetes. However, there are no real-world data available to illustrate the relevance for clinical practice.</p> <p>Methods</p> <p>Open, prospective, parallel group study comparing patients with an ACE inhibitor versus a diuretic based treatment. The principal aim was to document the first manifestation of type-2 diabetes in either group.</p> <p>Results</p> <p>A total of 2,011 patients were enrolled (mean age 69.1 ± 10.3 years; 51.6% female). 1,507 patients were available for the per-protocol analysis (1,029 ramipril, 478 diuretic group). New-onset diabetes was less frequent in the ramipril than in the diuretic group over 4 years. Differences were statistically different at a median duration of 3 years (24.4% vs 29.5%; p < 0.05). Both treatments were equally effective in reducing BP (14.7 ± 18.0/8.5 ± 8.2 mmHg and 12.7 ± 18.1/7.0 ± 8.3 mmHg) at the 4 year follow-up (p < 0.001 vs. baseline; p = n.s. between groups). In 38.6% and 39.7% of patients BP was below 130/80 mmHg (median time-to-target 3 months). There was a significant reduction of cardiovascular morbidity and mortality in favour of ramipril (p = 0.033). No significant differences were found for a change in HbA1c as well as for fasting blood glucose levels during follow-up. The rate of adverse events was higher in diuretic treated patients (SAE 15.4 vs. 12.4%; p < 0.05; AE 26.6 vs. 25.6%; p = n.s).</p> <p>Conclusions</p> <p>Ramipril treatment is preferable over diuretic based treatment regimens for the treatment of hypertension in pre-diabetic patients, because new-onset diabetes is delayed.</p