NSV 11749: Symbiotic Nova, Not a Born-Again Red Giant

NSV 11749 is a little-studied variable star, discovered by W. J. Luyten, which had a long-duration outburst around the year 1903, reaching blue magnitude 12.5 at maximum. Following the outburst, it has apparently been quiescent at about blue magnitude 17 for the past century. It was recently suggested that NSV 11749 may have been a low- or intermediate-mass star that underwent a final helium shell flash, making it temporarily a "born-again" red giant. If so, it would be only the fourth known member of this class, along with V605 Aql, FG Sge, and V4334 Sgr. However, our newly obtained optical and near-IR spectra of the object show that it is instead a symbiotic binary, with strong Balmer and He I-II emission lines, combined with a cool red-giant companion of spectral type M1-2 III. The 1903 outburst was most likely a symbiotic nova event, of which less than a dozen are known at present.Comment: 13 pages, 3 figures, Accepted for publication in PAS

Intermediate Palomar Transient Factory: Realtime Image Subtraction Pipeline

A fast-turnaround pipeline for realtime data reduction plays an essential role in discovering and permitting follow-up observations to young supernovae and fast-evolving transients in modern time-domain surveys. In this paper, we present the realtime image subtraction pipeline in the intermediate Palomar Transient Factory. By using high-performance computing, efficient database, and machine learning algorithms, this pipeline manages to reliably deliver transient candidates within ten minutes of images being taken. Our experience in using high performance computing resources to process big data in astronomy serves as a trailblazer to dealing with data from large-scale time-domain facilities in near future.Comment: 18 pages, 6 figures, accepted for publication in PAS

Detection of a-to-i rna editing in sars-cov-2

ADAR1-mediated deamination of adenosines in long double-stranded RNAs plays an important role in modulating the innate immune response. However, recent investigations based on metatranscriptomic samples of COVID-19 patients and SARS-COV-2-infected Vero cells have recovered contrasting findings. Using RNAseq data from time course experiments of infected human cell lines and transcriptome data from Vero cells and clinical samples, we prove that A-to-G changes observed in SARS-COV-2 genomes represent genuine RNA editing events, likely mediated by ADAR1. While the A-to-I editing rate is generally low, changes are distributed along the entire viral genome, are overrepresented in exonic regions, and are (in the majority of cases) nonsynonymous. The impact of RNA editing on virus–host interactions could be relevant to identify potential targets for therapeutic interventions

MRI Findings After a Subchondroplasty Procedure of the Ankle: A Case Report

Osteoarthritis (OA) of the ankle is a common disease and it is estimated that almost 1% of the world’s adult population have a painful ankle. Often in patients who fail conservative treatment, the use of an MRI is deemed necessary to identify pathologies. Bone marrow lesions (BMLs) seen on MRI have been recognized as a source of the ankle pain. Majority of the BMLs fluctuate in size over time and are seen as hyperintense lesions on MRI.We present MRI findings of a patient following arthroscopy with subchondroplasty

Sensitivity analysis of marine Controlled-Source Electromagnetic data

Electromagnetic sounding methods represent one of the few geophysical techniques that can provide information about the state and the properties of deep continental crust and upper mantle. In particular, marine Controlled-Source Electromagnetic (mCSEM) method is being applied to offshore hydrocarbon exploration and providing encouraging results, as it can complement the information obtained from seismic elaborations, mainly the position of the elastic discontinuities, with a map of electrical conductivity, the principal "discriminator" between conductive water-bearing rocks and non-conductive hydrocarbon accumulations. The processing of mCSEM data can be problematic due to the non-uniqueness of the solution, the environmental and equipment noise, and the high computational power required when dealing with 3D inversion. This paper proposes a simplified procedure to study and rank the sensitivity of mCSEM in a canonical 1D scenario, with a single resistive anomaly embedded in a homogeneous background. We analyze the sensitivity of the data with respect to the most important test parameters, namely the frequency, target depth, thickness, and resistivity. In addition, this procedure is also utilized to validate the so-called T-equivalence theorem. The results of this study could assist the interpreter to highlight the reliability of the inverted parameters in a complex inversion environment

Torsion and the Gravity Dual of Parity Symmetry Breaking in AdS4/CFT3 Holography

We study four dimensional gravity with a negative cosmological constant deformed by the Nieh-Yan torsional topological invariant with a spacetime-dependent coefficient. We find an exact solution of the Euclidean system, which we call the torsion vortex, having two asymptotic AdS4 regimes supported by a pseudoscalar with a kink profile. We propose that the torsion vortex is the holographic dual of a three dimensional system that exhibits distinct parity breaking vacua. The torsion vortex represents a (holographic) transition between these distinct vacua. We expect that from the boundary point of view, the torsion vortex represents a `domain wall' between the two distinct vacua. From a bulk point of view, we point out an intriguing identification of the parameters of the torsion vortex with those of an Abrikosov vortex in a Type I superconductor. Following the analogy, we find that external Kalb-Ramond flux then appears to support bubbles of flat spacetime within an asymptotically AdS geometry.Comment: 26 pages, 4 figures; v2: minor improvements, references adde

Pediatric intestinal obstruction in Malawi: characteristics and outcomes

Abstract Background Intestinal obstruction (IO) is a common pediatric surgical emergency in sub-Saharan Africa with high morbidity and mortality, but little is known about its etiopathogenesis in Malawi. Methods Retrospective analysis of patients seen from February 2012 to June 2014 at Kamuzu Central Hospital in Lilongwe, Malawi (n = 3,407). Pediatric patients with IO were analyzed (n = 130). Results Overall, 57% of patients were male with a mean age of 3.5 ± 4.1 years. A total of 52% of patients underwent operative intervention. The overall mortality rate was 3%. Leading causes of IO were Hirschprung's 29%, anorectal malformation 18%, and intussusception 4%. Neonates and patients with congenital causes of IO underwent surgery less frequently than infants and/or children and patients with acquired causes, respectively. These groups also demonstrated increased number of days from admission to surgery. Conclusions Increasing pediatric-specific surgical education and/or training and expanding access to resources may improve mortality after IO in poor medical communities within sub-Saharan Africa

A new and unusual LBV-like outburst from a Wolf–Rayet star in the outskirts of M33

MCA-1B (also called UIT003) is a luminous hot star in the western outskirts of M33, classified over 20 yr ago with a spectral type of Ofpe/WN9 and identified then as a candidate luminous blue variable (LBV). Palomar Transient Factory data reveal that this star brightened in 2010, with a light curve resembling that of the classic LBV star AF And in M31. Other Ofpe/WN9 stars have erupted as LBVs, but MCA-1B was unusual because it remained hot. It showed a WN-type spectrum throughout its eruption, whereas LBVs usually get much cooler. MCA-1B showed an almost four-fold increase in bolometric luminosity and a doubling of its radius, but its temperature stayed ≳29 kK. As it faded, it shifted to even hotter temperatures, exhibiting a WN7/WN8-type spectrum, and doubling its wind speed. MCA-1B is reminiscent of some supernova impostors, and its location resembles the isolated environment of SN 2009ip. It is most similar to HD 5980 (in the Small Magellanic Cloud) and GR 290 (also in M33). Whereas these two LBVs exhibited B-type spectra in eruption, MCA-1B is the first clear case where a Wolf–Rayet (WR) spectrum persisted at all times. Together, MCA-1B, HD 5980, and GR 290 constitute a class of WN-type LBVs, distinct from S Doradus LBVs. They are most interesting in the context of LBVs at low metallicity, a possible post-LBV/WR transition in binaries, and as likely Type Ibn supernova progenitors

Echocardiography allows for analysis of pulmonary arterial flow in mice with congenital diaphragmatic hernia

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a structural birth defect associated with pulmonary hypoplasia and pulmonary arterial hypertension (PAH). We hypothesize that echocardiography provides a method to assess real-time right ventricle (RV) function, remodeling, and pulmonary artery (PA) flow. MATERIALS AND METHODS: Slit3 wild-type (WT) (n = 6) and knockout (KO) (n = 5) mice were analyzed at 2-3 months of age. Mice were anesthetized using isoflurane. Echocardiography was performed to analyze left and right ventricular wall thickness, internal diameter (ID), and function. Color Doppler was used to analyze flow in the PA and across the tricuspid valve. RESULTS: There was significant RV dilation in the KO mice versus WT, with an average RVID of 1.99 mm versus 1.26 mm, respectively (P = 0.007). Flow in the PA of KO mice was altered compared to WT, with elevated PA velocity time indices, 30.68 mm versus 22.13 mm (P = 0.012), elevated PA peak velocities, 952.61 mm/s versus 628.73 mm/s (P = 0.003), and decreased pulmonary acceleration times, 8.94 ms versus 16.18 ms (P = 0.002), respectively. Pulmonary vascular resistance, calculated by measuring tricuspid regurgitation peak velocity and right ventricular outflow tract velocity time index, was increased in KO versus WT mice, 17.61 mm2/s versus 8.91 mm2/s (P = 0.003), respectively. CONCLUSIONS: Slit3 KO mice with CDH show evidence of PAH and resultant RV dilation. Using direct cardiac puncture, elevated RV systolic pressures have been demonstrated in KO mice as evidence of PAH. Echocardiography allows direct analysis of the PA and real-time RV function without sacrifice of the mouse. This mode of evaluation allows longitudinal study in mice with PAH and CDH