Nonlinear c-axis transport in Bi_2Sr_2CaCu_2O_(8+d) from two-barrier tunneling

Motivated by the peculiar features observed through intrinsic tunneling spectroscopy of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ mesas in the normal state, we have extended the normal state two-barrier model for the c-axis transport [M. Giura et al., Phys. Rev. B {\bf 68}, 134505 (2003)] to the analysis of $dI/dV$ curves. We have found that the purely normal-state model reproduces all the following experimental features: (a) the parabolic $V$-dependence of $dI/dV$ in the high-$T$ region (above the conventional pseudogap temperature), (b) the emergence and the nearly voltage-independent position of the "humps" from this parabolic behavior lowering the temperature, and (c) the crossing of the absolute $dI/dV$ curves at a characteristic voltage $V^\times$. Our findings indicate that conventional tunneling can be at the origin of most of the uncommon features of the c axis transport in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. We have compared our calculations to experimental data taken in severely underdoped and slightly underdoped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ small mesas. We have found good agreement between the data and the calculations, without any shift of the calculated dI/dV on the vertical scale. In particular, in the normal state (above $T^\ast$) simple tunneling reproduces the experimental dI/dV quantitatively. Below $T^\ast$ quantitative discrepancies are limited to a simple rescaling of the voltage in the theoretical curves by a factor $\sim$2. The need for such modifications remains an open question, that might be connected to a change of the charge of a fraction of the carriers across the pseudogap opening.Comment: 7 pages, 5 figure

Quality of life after tailored combined surgery for stage I non-small-cell lung cancer and severe emphysema

Background. We analyzed the early and long-term quality of life changes occurring in 16 patients undergoing tailored combined surgery for stage I non-small-cell lung cancer (NSCLC) and severe emphysema. Methods. Mean age was 65 +/- 5 years. All patients had severe emphysema with severely impaired respiratory function and quality of life. Tumor resection was performed with sole lung volume reduction (LVR) in 5 patients, separate wedge resection in 3 patients, segmentectomy in 2 patients, and lobectomy in 6 patients. A bilateral LVR was performed in 5 patients. Quality of life was assessed at baseline and every 6 months postoperatively by the Short-form 36 (SF-36) item questionnaire. Results. Mean follow-up was 44 +/- 21 months. All tumors were pathologic stage I. There was no hospital mortality nor major morbidity. Significant improvements occurred for up to 36 months in the general health (p = 0.02) domain and for up to 24 months in physical functioning (p = 0.02), role physical (p = 0.005), and general health (P = 0.01) SF-36 domains. Associated improvements regarded dyspnea index (-1.3 +/- 0.6) forced expiratory volume in one second (+0.28 +/- 0.2L), residual volume (-1.18 +/- 0.5L) and 6-minute-walking test distance (+86 +/- 67 m). Actuarial 5-year survival was similar to that of patients with no cancer undergoing LVRS during the same period (68% vs 82%, p = not significant). Conclusions. Our study suggests that selected patients with stage I NSCLC and severe emphysema may significantly benefit from tailored combined surgery in terms of long-term quality of life and survival. (Ann Thorac Surg 2003;76:1821-7

Gene Transfer of Engineered Calmodulin Alleviates Ventricular Arrhythmias in a Calsequestrin-Associated Mouse Model of Catecholaminergic Polymorphic Ventricular Tachycardia

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial arrhythmogenic syndrome characterized by sudden death. There are several genetic forms of CPVT associated with mutations in genes encoding the cardiac ryanodine receptor (RyR2) and its auxiliary proteins including calsequestrin (CASQ2) and calmodulin (CaM). It has been suggested that impairment of the ability of RyR2 to stay closed (ie, refractory) during diastole may be a common mechanism for these diseases. Here, we explore the possibility of engineering CaM variants that normalize abbreviated RyR2 refractoriness for subsequent viral-mediated delivery to alleviate arrhythmias in non-CaM-related CPVT

Galactic axions search with a superconducting resonant cavity

To account for the dark matter content in our Universe, post-inflationary scenarios predict for the QCD axion a mass in the range (10-10^3)\,\mu\mbox{eV}. Searches with haloscope experiments in this mass range require the monitoring of resonant cavity modes with frequency above 5\,GHz, where several experimental limitations occur due to linear amplifiers, small volumes, and low quality factors of Cu resonant cavities. In this paper we deal with the last issue, presenting the result of a search for galactic axions using a haloscope based on a 36\,\mbox{cm}^3 NbTi superconducting cavity. The cavity worked at T=4\,\mbox{K} in a 2\,T magnetic field and exhibited a quality factor $Q_0= 4.5\times10^5$ for the TM010 mode at 9\,GHz. With such values of $Q$ the axion signal is significantly increased with respect to copper cavity haloscopes. Operating this setup we set the limit g_{a\gamma\gamma}<1.03\times10^{-12}\,\mbox{GeV}^{-1} on the axion photon coupling for a mass of about 37\,$\mu$eV. A comprehensive study of the NbTi cavity at different magnetic fields, temperatures, and frequencies is also presented

Discovery of underground argon with low level of radioactive 39Ar and possible applications to WIMP dark matter detectors

We report on the first measurement of 39Ar in argon from underground natural gas reservoirs. The gas stored in the US National Helium Reserve was found to contain a low level of 39Ar. The ratio of 39Ar to stable argon was found to be <=4x10-17 (84% C.L.), less than 5% the value in atmospheric argon (39Ar/Ar=8x10-16). The total quantity of argon currently stored in the National Helium Reserve is estimated at 1000 tons. 39Ar represents one of the most important backgrounds in argon detectors for WIMP dark matter searches. The findings reported demonstrate the possibility of constructing large multi-ton argon detectors with low radioactivity suitable for WIMP dark matter searches.Comment: 6 pages, 2 figures, 2 table

ESPRAS Survey on Continuing Education in Plastic, Reconstructive and Aesthetic Surgery in Europe

Background Specialty training in plastic, reconstructive and aesthetic surgery is a prerequisite for safe and effective provision of care. The aim of this study was to assess and portray similarities and differences in the continuing education and specialization in plastic surgery in Europe. Material and Methods A detailed questionnaire was designed and distributed utilizing an online survey administration software. Questions addressed core items regarding continuing education and specialization in plastic surgery in Europe. Participants were addressed directly via the European Leadership Forum (ELF) of the European Society of Plastic, Reconstructive and Aesthetic Surgery (ESPRAS). All participants had detailed knowledge of the organization and management of plastic surgical training in their respective country. Results The survey was completed by 29 participants from 23 European countries. During specialization, plastic surgeons in Europe are trained in advanced tissue transfer and repair and aesthetic principles in all parts of the human body and within several subspecialties. Moreover, rotations in intensive as well as emergency care are compulsory in most European countries. Board certification is only provided for surgeons who have had multiple years of training regulated by a national board, who provide evidence of individually performed operative procedures in several anatomical regions and subspecialties, and who pass a final oral and/or written examination. Conclusion Board certified plastic surgeons meet the highest degree of qualification, are trained in all parts of the body and in the management of complications. The standard of continuing education and qualification of European plastic surgeons is high, providing an excellent level of plastic surgical care throughout Europe

Spontaneous versus mechanical ventilation during video-assisted thoracoscopic surgery for spontaneous pneumothorax: a randomized trial

Objective: Spontaneous ventilation video-assisted thoracic surgery (SV-VATS) is reported to have superior or equal efficacy on postoperative recovery to mechanical ventilation VATS (MV-VATS). However, perioperative safety of the SV-VATS blebectomy is not entirely demonstrated. Methods: We performed a noninferiority, randomized controlled trial (No. NCT03016858) for primary spontaneous pneumothorax patients aged 16 to 50 years undergoing a SV-VATS and the MV-VATS procedure. The trial was conducted at 10 centers in China from April 2017 to January 2019. The primary outcome was the comparison of intra- and postoperative complications between SV-VATS and MV-VATS procedures. Secondary outcomes included total analgesia dose, change of vital sign during surgery, procedural duration, recovery time, postoperative visual analog pain scores, and hospitalization length. Results: In this study, 335 patients were included. There was no significant difference between the SV-VATS group and the MV-VATS group in the intra- and postoperative complication rates (17.90% vs 22.09%; relative risk, 0.81; 95% confidence interval, 0.52-1.26; P = .346). The SV-VATS group was associated with significantly decreased total dose of intraoperative opioid agents; that is, sufentanil (11.37 μg vs 20.92 μg; P &lt; .001) and remifentanil (269.78 μg vs 404.96 μg; P &lt; .001). The SV-VATS procedure was also associated with shorter extubation time (12.28 minutes vs 17.30 minutes; P &lt; .001), postanesthesia care unit recovery time (25.43 minutes vs 30.67 minutes; P = .02) and food intake time (346.07 minute vs 404.02 minutes; P = .002). Moreover, the SV-VATS procedure deceased the anesthesia cost compared with the MV-VATS ($297.81 vs$399.81; P &lt; .001). Conclusions: SV-VATS was shown to be noninferior to MV-VATS in term of complication rate and in selected patients undergoing blebectomy for primary spontaneous pneumothorax