Two-Proton Radioactivity with 2p halo in light mass nuclei A==18−-34

Two-proton radioactivity with 2p halo is reported theoretically in light mass nuclei A $=$ 18-34. We predict $^{19}$Mg, $^{22}$Si, $^{26}$S, $^{30}$Ar and $^{34}$Ca as promising candidates of ground state 2p-radioactivity with S$_{2p}$ $$ 0. Observation of extended tail of spatial charge density distribution, larger charge radius and study of proton single particle states, Fermi energy and the wave functions indicate 2p halo like structure which supports direct 2p emission. The Coulomb and centrifugal barriers in experimentally identified 2p unbound $^{22}$Si show a quasi-bound state that ensures enough life time for such experimental probes. Our predictions are in good accord with experimental and other theoretical data available so far.Comment: 5 Pages, 5 figure

A Survey of Digital Watermarking Techniques

Volume 1 Issue 6 (August 2013

Evolution of Shapes and Search for Shape Coexistence in Sd-Shell Nuclei

A detailed and systematic study has been performed using state dependent Relativistic Mean-Field plus BCS (RMF+BCS) approach to investigate shape evolution for even-even isotopes of Ne, Mg, Si and S. We perform quadrupole constraint calculation using NL3* parameter and look into the variation of binding energy with respect to deformation and find the shape and deformation corresponding to energy minima. We find various isotopes showing shape coexistence and shape transition while moving from proton drip-line to neutron drip-line. These results are compared with Macroscopic-microscopic approach (Mac-Mic) with Nilson Strutinsky (NS) prescription and some other works and are found consistent for these sd-shell nuclei

Mechanical suppression of premature ventricular complexes during catheter ablation procedures

Introduction: Mechanical suppression of premature ventricular complexes (PVCs) is not a well-known observation. We retrospectively reviewed this phenomenon in the Ventricular Arrhythmia (VA) ablation procedures performed at Richard L. Roudebush Veterans Health Administration (VHA) center. Methods: Data from 40 consecutive patients who underwent VA ablation at VHA, Indianapolis, IN, with 44 VA was included in the study. Demographic and electrophysiological parameter data was collected. Results: Overall the mean age of the population was 64 ± 11 years. The phenomenon of mechanical suppression was seen in 11 PVCs. The mean age was 59 ± 15 years in the group in which mechanical suppression was seen. Of the 11 cases, the site of earliest activation was seen in the coronary sinus in 8 and in the pulmonary artery in 3. In one case catheter ablation was not performed because of proximity to the left coronary artery system. However, sustained pressure at the site with earliest electrograms (-35 ms) and 95% pacematch resulted in long-term suppression of PVCs. In the cases in which mechanical suppression was seen, there was a statistically significant reduction in PVC burden compared to pre ablation PVC load (1.1% ± 1.50% (post ablation) versus 24.04% ± 13.07% (pre ablation) versus p < 0.05). In all the 11 cases the site of mechanical suppression was also the site with earliest electrograms. Conclusion: This case series illustrates phenomenon of mechanical suppression of PVCs as an indication for good site for successful ablation in unique veteran patient population

Unique features of epicardial ventricular arrhythmias/premature ventricular complexes ablated from coronary venous system in veteran population

Introduction: Ventricular arrhythmias/premature ventricular complexes (VA/PVCs) that can be ablated from within the coronary venous system (CVS) have not been described in the United States Veterans Health Administration (VHA) population. We retrospectively studied the VA/PVCs ablations that were performed in the VHA population. Methods: Data from 42 consecutive patients who underwent VA/PVCs ablation at Veterans Affairs Hospital, Indianapolis, IN, with 44 VA/PVCs was included in the study. Patients were divided into two groups (CVS group [n = 10], and non-CVS group [n = 32]) based on where the earliest pre-systolic activation was seen with >95% pacematch. Results: The mean age in CVS group was 65 ± 8 years versus 64 ± 12 years (p = 0.69) in non-CVS group. Overall there was a statistically significant reduction in PVC burden post ablation (27.7% (pre-ablation) versus 4.7% (post-ablation). In the 10 patients in the CVS group, either ablation or catheter-related mechanical trauma resulted in complete (n = 6 [60%]) or partial (n = 4 [40%]) long-term suppression of VA/PVCs. Right bundle branch block-type VA/PVC (9/11: 82%) was the most common morphology in the CVS group, whereas in the non-CVS group, this type was seen in only 3/33 (9%). The CVS group (25% of total VA/PVCs) had shorter activation time compared to non CVS group. Conclusion: In our experience VA/PVCs with electrocardiograms suggestive of epicardial origin can often be safely and successfully ablated within the coronary venous system. These arrhythmias have unique features in Veterans patient population

Who Is at Risk for New Hepatitis B Infections Among People With HIV?

Hepatitis B virus (HBV) increases morbidity and mortality among people with HIV (PWH). We retrospectively analyzed HBV incidence among 5785 PWH. Fourteen had newly positive hepatitis B s antigen (mean 5.2 person-years of follow-up, 46.4/100 000 infections/year). These data show gaps in HBV vaccination and in the preventative efficacy of HBV-specific antiretroviral therapy

Natural History Of Implantable Cardioverter-Defibrillator Implanted At Or After The Age Of 70 Years In A Veteran Population A Single Center Study

Background: The median age of patients in major Implantable Cardioverter-defibrillator (ICD)trials (MUSTT, MADIT-I, MADIT-II, and SCD-HeFT) was 63-67 years; with only 11% ≥70 years. There is little follow-up data on patients over 70 years of age who received an ICD for primary/secondary prevention of sudden cardiac death, particularly for veterans. Objective: The aim of this study was to study the natural history of ICD implantation for veterans over 70 years of age. Methods: We retrospectively reviewed single center ICD data in 216 patients with a mean age at implantation 76 ± 4 years. The ICD indication was primary prevention in 161 patients and secondary prevention in 55 patients. The ICD indication was unavailable in 4 patients. Results: Mean duration of follow up was 1686 ± 1244 days during which 114 (52%) patients died. Of these, 31% died without receiving any appropriate ICD therapy. Overall, 60/216 (28%) received appropriate therapy and 28/216 (13%) received inappropriate therapy. Patients who had ICD implantation for secondary prophylaxis had statistically more (p= 0.02) appropriate therapies compared to patients who had ICD implantation for primary prevention. Indication for implantation and hypertension predicted appropriate therapy, while age at the time of implantation and presence of atrial fibrillation predicted inappropriate therapies. Overall, 7.7% had device related complications. Conclusions: Although 28% septuagenarians in this study received appropriate ICD therapy, they had high rates of mortality, inappropriate therapy, and device complications. ICD implantation in the elderly merits individualized consideration, with higher benefit for secondary prevention