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The electrical resistance of solid and liquid Bi has been measured at high pressures and temperatures using a novel experimental design for high sensitivity measurements utilizing a "Paris-Edinburgh" toroid large volume press. An anomalous sharp decrease in resistivity with increasing temperature at constant pressureswas observed in the region beyond melting which implies a possible novel transition in the melt. The proposed transition was observed across a range of pressures both in heating and cooling cycles of the sample demonstrating its reversibility. From the measurements it was possible to determine a "phase-line" of this transition on the Bi pressure-temperature phase diagram terminating at the melting curve. [ABSTRACT FROM AUTHOR]

Partly resistive superconducting quantum interference devices (RSQUIDs) are used in noise thermometry in the liquid helium temperature range. Here we analyze one type of RSQUID that has not been thoroughly investigated until now: the direct current biased with two Josephson junctions and a resistive part connected in series with the junctions and closed by a superconducting ring. The resistive shunted model of the Josephson junctions is used for the analysis. Two cases of the RSQUID ring inductance were analyzed: (i) negligibly small and (ii) small but finite inductance. The expressions for the low frequency output signal, the current-voltage (I- V) characteristics, and the current flowing through the resistive part are obtained. In the dependence of the output frequency versus the dc current passed through the resistive part often an offset is observed experimentally. This phenomenon can be explained as an influence of an asymmetry in the critical currents of the junctions. [ABSTRACT FROM AUTHOR]

Focuses on a study which developed a theory of double signal and noise performance of superconducting quantum interferometer with two quantization loops (D-SQUID). Types of SQUID; Critical points of D-SQUID; Interaction of the D-SQUID with a tank circuit; Noise properties of SQUID.

Aminoacyl tRNA synthetases--enzymes that catalyze the first step of protein synthesis--in mammalian cells are now known to have expanded functions, including activities in signal transduction pathways, such as those for angiogenesis and inflammation. The native synthetases themselves are procytokines, having no signal transduction activities. After alternative splicing or natural proteolysis, specific fragments that are potent cytokines and that interact with specific receptors on cell surfaces are released. In this manner, a natural fragment of human tyrosyl tRNA synthetase (TyrRS), mini-TyrRS, has been shown to act as a proangiogenic cytokine. The mechanistic basis for the action of mini-TyrRS in angiogenesis has yet to be established. Here, we show that mini-TyrRS is exported from endothelial cells when they are treated with tumor necrosis factor-or. Mini-TyrRS binds to vascular endothelial cells and activates an array of angiogenic signal transduction pathways. Mini-TyrRS-induced angiogenesis requires the activation of vascular endothelial growth factor receptor-2 (VEGFR2/Flk-1/KDR). Mini-TyrRS stimulates VEGFR2 phosphorylation in a VEGF-independent manner, suggesting VEGFR2 transactivation. Transactivation of VEGFR2 and downstream angiogenesis require an intact Glu-Leu-Arg (ELR) motif in mini-TyrRS, which is important for its cytokine activity. These studies therefore suggest a mechanism by which mini-TyrRS induces angiogenesis in endothelial cells and provide further insight into the role of mini-TyrRS as a link between translation and angiogenesis. [ABSTRACT FROM AUTHOR]

Introduction The purpose of this study was to evaluate the efficacy of a dual-coil, active-can implantable cardioverter-defibrillator (ICD) system, implanted for the treatment of ventricular arrhythmias, in cardioversion of spontaneous episodes of atrial fibrillation (AF). Methods The population was derived from 360 patients with icds implanted between July 1997 and June 2001. The study patients were 69 ± 8.9 years old, 83% were male, coronary artery disease was present in 78%, and a prior history of non-permanent AF was present in 54%. Beta blockers were used in 72% of patients and amiodarone in 27% of patients. The mean left ventricular ejection fraction was 31 ± 9%. Echocardiographic evaluation demonstrated moderate to severe left atrial enlargement in 41% of patients. Patients with permanent AF were excluded. Results Atrial fibrillation resulted in an ICD discharge in 23 patients. Successful cardioversion occurred in 79% of episodes of AF with defibrillation energy of 30.5 ± 4.4 joules. In multivariate analysis, no patient characteristics, including left atrial size, ejection fraction, or concurrent use of beta blockers or amiodarone predicted success of cardioversion. Multiple discharges were delivered in 17% of these patients. Conclusion Standard dual-coil, active-can ICD systems are highly successful at converting spontaneous AF that occurs in the clinical setting. There were no specialized defibrillation coils or algorithms required. The use of discriminatory algorithms for prevention of multiple ICD discharges due to atrial arrhythmias needs to be balanced with the high success rate of cardioversion. [ABSTRACT FROM PUBLISHER]

Introduction We evaluated the use of implantable defibrillators (ICDs) in the octogenarian population to analyze the complications associated with ICD implantation; the incidence of appropriate and inappropriate discharges; as well as survival following ICD implantation. Methods We retrospectively evaluated the utilization of ICDs implanted and followed at our institution from 1998 to 2004 in the octogenarian population with systolic dysfunction. A control group was comprised of similar patients under the age of 80. Patients with preserved ventricular function were excluded. Results Two hundred twenty-six patients with systolic dysfunction were evaluated following ICD implantation. There were 51 patients over 80 years of age (mean age: 84 ± 4). A control group of 175 patients less than age 80 (mean age: 66 ± 10) was utilized for comparison. The baseline characteristics, including ejection fraction (25 ± 7%), presence of coronary disease (90%), as well as the incidence of symptomatic arrhythmias (33%) were similar in both groups. The octogenarian population did have a higher percentage of women (31% v. 18% (p = 0.04)). The long-term device related complication rate in the older age group was low (1.9%) and did not differ between groups. Thirty-two percent of the octogenarian group received appropriate ICD therapy over a mean follow-up period of 15 ± 16 months. The older group had fewer inappropriate discharges (6.8% v. 12.6%; p = NS) in comparison to the younger patient group. Although 78.4% of the octogenarian group survived during the follow-up period, there was a significant decrease in survival in this group as evaluated by the Kaplan Meier method (p=0.0003). In multivariate analysis, the only significant predictor of survival was age less than 80. Conclusion The octogenarian population can safely be treated with ICD therapy and in appropriately selected patients; they can be expected to have a high rate of therapeutic ICD utilization. Patients should be carefully selected for ICD implantation as mortality is higher in the octogenarian population and co-morbid conditions may limit the potential survival benefit offered by the ICD. [ABSTRACT FROM PUBLISHER]

Abstract: La1/3NbO3, an A-site cation deficient double perovskite, has been studied under pressure by synchrotron X-ray powder diffraction and Raman spectroscopy. In contrast to other highly distorted perovskites, transforming to post-perovskite on compression, La1/3NbO3 undergoes irreversible pressure induced amorphization at ~14.5GPa. Over a wide range of pressure before that transition it presents an almost linear volume decrease versus pressure, accompanied by convergence form orthorhombic to a cubic unit cell. The Raman spectroscopy also shows an amorphization at the same pressure. However, where upon full decompression the X-ray diffraction pattern remains amorphous, new Raman peaks become active. [Copyright &y& Elsevier]

Primary tumoral calcinosis is a rare and benign condition characterized by calcium salt deposition in periarticular soft tissues. It typically presents as a firm, rubbery mass that arises around large joints. While an estimated 250 cases have been described since its discovery, very few cases have been identified in the hand. We present a case of multiple calcified masses in the hand, one of which required meticulous dissection from a digital neurovascular bundle, and our technique for surgical excision. We present this case to lower the threshold for clinical suspicion of tumoral calcinosis for patients who present with a soft tissue mass in the hand. Furthermore, we recommend prompt surgical excision due to low success rates of alternative treatment options and to prevent potential neurovasculature or tendon injury., (Published by Elsevier B.V. on behalf of Society for Indian Hand Surgery and Micro Surgeons.)

Background: Favorable clinical outcomes are difficult to achieve in long-standing persistent atrial fibrillation (LSPAF) with catheter ablation (CA). The CONVERGE (Convergence of Epicardial and Endocardial Ablation for the Treatment of Symptomatic Persistent Atrial FIbrillation) trial evaluated the effectiveness of hybrid convergent (HC) ablation vs endocardial CA., Objective: The study sought to evaluate the safety and effectiveness of HC vs CA in the LSPAF subgroup from the CONVERGE trial., Methods: The CONVERGE trial was a prospective, multicenter, randomized trial that enrolled 153 patients at 27 sites. A post hoc analysis was performed on LSPAF patients. The primary effectiveness was freedom from atrial arrhythmias off new or increased dose of previously failed or intolerant antiarrhythmic drugs (AADs) through 12 months. The primary safety endpoint was major adverse event incidence through 30 days with HC. Key secondary effectiveness measures included (1) percent of patients achieving ≥90% AF burden reduction vs baseline and (2) AF freedom., Results: Sixty-five patients (42.5% of total enrollment) had LSPAF; 38 in HC and 27 in CA. Primary effectiveness was 65.8% (95% confidence interval [CI] 50.7%-80.9%) with HC vs 37.0% (95% CI 5.1%-52.4%) with CA ( P = .022). Through 18 months, these rates were 60.5% (95% CI 50.0%-76.1%) with HC vs 25.9% (95% CI 9.4%-42.5%) with CA ( P = .006). Secondary effectiveness rates were higher than CA with HC at 12 and 18 months. Freedom from atrial arrhythmias off AADs was 52.6% (95% CI 36.8%-68.5%) and 47.4% (95% CI 31.5%-63.2%) with HC at 12 and 18 months vs 25.9% (95% CI 9.4%-42.5%) and 22.2% (95% CI 6.5%-37.9%) with CA, respectively (12 months: P = .031; 18 months: P = .038). Three (7.9%) major adverse events occurred within 30 days of HC., Conclusion: Post hoc analysis demonstrated effectiveness and acceptable safety of HC compared with CA in LSPAF., (© 2022 Heart Rhythm Society. Published by Elsevier Inc.)

Abstract: Subglossopalatal membrane (or subglossopalatal synechia) is a rare clinical entity that can lead to respiratory distress and feeding difficulty due to oral obstruction. Here, the authors present a case of subglossopalatal membrane with associated cleft palate and cardiovascular and neurologic anomalies that was treated with surgical excision and lip-tongue adhesion. Etiology of these membranes is believed to be intrauterine fetal insult. Membranes should be treated with excision, whereas taking care to ensure patency of the airway. Presence of a subglossopalatal membrane should prompt thorough examination for additional congenital anomalies., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)