Planetary Nebulae with Ultra-Violet Imaging Telescope (UVIT): Far Ultra-violet halo around the Bow Tie nebula (NGC 40)

Context. NGC 40 is a planetary nebula with diffuse X-ray emission, suggesting an interaction of the high speed wind from WC8 central star (CS) with the nebula. It shows strong Civ 1550 {\AA} emission that cannot be explained by thermal processes alone. We present here the first map of this nebula in C IV emission, using broad band filters on the UVIT. Aims. To map the hot C IV emitting gas and its correspondence with soft X-ray (0.3-8 keV) emitting regions, in order to study the shock interaction with the nebula and the ISM. This also illustrates the potential of UVIT for nebular studies. Methods. Morphological study of images of the nebula obtained at an angular resolution of about 1.3" in four UVIT filter bands that include C IV 1550 {\AA} and C II] 2326 {\AA} lines and UV continuum. Comparisons with X-ray, optical, and IR images from literature. Results. The C II] 2326 {\AA} images show the core of the nebula with two lobes on either side of CS similar to [N II]. The C IV emission in the core shows similar morphology and extant as that of diffuse X-ray emission concentrated in nebular condensations. A surprising UVIT discovery is the presence of a large faint FUV halo in FUV Filter with {\lambda}eff of 1608 {\AA}. The UV halo is not present in any other UV filter. FUV halo is most likely due to UV fluorescence emission from the Lyman bands of H2 molecules. Unlike the optical and IR halo, FUV halo trails predominantly towards south-east side of the nebular core, opposite to the CS's proper motion direction. Conclusions. Morphological similarity of C IV 1550 {\AA} and X-ray emission in the core suggests that it results mostly from interaction of strong CS wind with the nebula. The FUV halo in NGC 40 highlights the existence of H2 molecules extensively in the regions even beyond the optical and IR halos.Comment: 4 pages, 5 figures, accepted for publication as a letter in Astronomy & Astrophysic

Data Augmentation for Low-Resource Keyphrase Generation

Keyphrase generation is the task of summarizing the contents of any given article into a few salient phrases (or keyphrases). Existing works for the task mostly rely on large-scale annotated datasets, which are not easy to acquire. Very few works address the problem of keyphrase generation in low-resource settings, but they still rely on a lot of additional unlabeled data for pretraining and on automatic methods for pseudo-annotations. In this paper, we present data augmentation strategies specifically to address keyphrase generation in purely resource-constrained domains. We design techniques that use the full text of the articles to improve both present and absent keyphrase generation. We test our approach comprehensively on three datasets and show that the data augmentation strategies consistently improve the state-of-the-art performance. We release our source code at https://github.com/kgarg8/kpgen-lowres-data-aug.Comment: 9 pages, 8 tables, To appear at the Findings of the Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics, Toronto, Canad

Planetary Nebulae with UVIT II: Revelations from FUV vision of Butterfly Nebula NGC 6302

The high excitation planetary nebula, NGC 6302, has been imaged in two far-ultraviolet (FUV) filters, F169M (Sapphire; {\lambda}$_{\rm eff}$: 1608 {\AA}) and F172M (Silica; {\lambda}$_{\rm eff}$: 1717 {\AA}) and two NUV filters, N219M (B15; {\lambda}$_{\rm eff}$: 2196 {\AA}) and N279N (N2; {\lambda}$_{\rm eff}$: 2792 {\AA}) with the Ultra Violet Imaging Telescope (UVIT). The FUV F169M image shows faint emission lobes that extend to about 5 arcmin on either side of the central source. Faint orthogonal collimated jet-like structures are present on either side of the FUV lobes through the central source. These structures are not present in the two NUV filters nor in the FUV F172M filter. Optical and IR images of NGC 6302 show bright emission bipolar lobes in the east-west direction with a massive torus of molecular gas and dust seen as a dark lane in the north-south direction. The FUV lobes are much more extended and oriented at a position angle of 113{\deg}. They and the jet-like structures might be remnants of an earlier evolutionary phase, prior to the dramatic explosive event that triggered the Hubble type bipolar flows approximately 2200 years ago. The source of the FUV lobe and jet emission is not known, but is likely due to fluorescent emission from H$_2$ molecules. The cause of the difference in orientation of optical and FUV lobes is not clear and, we speculate, could be related to two binary interactions.Comment: 9 pages, 5 figures, accepted for publication in Astronomy & Astrophysic

Non-classical congenital adrenal hyperplasia presenting as primary amenorrhoea with virilization

Primary amenorrhea presents a diagnostic challenge even to the most experienced clinicians. The number, variety and the complexity of disorder that must be considered can seem daunting and in many instances include unfamiliar organ system. One such disorder is congenital adrenal hyperplasia (CAH). Here, we present a case of Non-classical congenital adrenal hyperplasia in a 16 year old female who presented to us with primary amenorrhea with virilization. This is an interesting case because of its unusual presentation, difficulty in diagnosis and complexity involved in treatment

Improved rate-distance trade-offs for quantum codes with restricted connectivity

For quantum error-correcting codes to be realizable, it is important that the qubits subject to the code constraints exhibit some form of limited connectivity. The works of Bravyi & Terhal (BT) and Bravyi, Poulin & Terhal (BPT) established that geometric locality constrains code properties -- for instance $[[n,k,d]]$ quantum codes defined by local checks on the $D$-dimensional lattice must obey $k d^{2/(D-1)} \le O(n)$. Baspin and Krishna studied the more general question of how the connectivity graph associated with a quantum code constrains the code parameters. These trade-offs apply to a richer class of codes compared to the BPT and BT bounds, which only capture geometrically-local codes. We extend and improve this work, establishing a tighter dimension-distance trade-off as a function of the size of separators in the connectivity graph. We also obtain a distance bound that covers all stabilizer codes with a particular separation profile, rather than only LDPC codes.Comment: 15 pages, 2 figure