Does Political Affirmative Action Work, and for Whom? Theory and Evidence on India’s Scheduled Areas

Does political affirmative action undermine or promote development, and for whom? We examine Scheduled Areas in India, which reserve political office for the historically disadvantaged Scheduled Tribes. We apply a new theoretical framework and dataset of 217,000 villages to evaluate the overall impact of affirmative action on development, as well as its distributional consequences for minorities and non-minorities. Examining effects on the world’s largest employment program, the National Rural Employment Guarantee Scheme, we find that reservations deliver no worse overall outcomes, that there are large gains for targeted minorities, and that these gains come at the cost of the relatively privileged, not other minorities. We also find broader improvements in other pro-poor policies, including a rural roads program and general public goods. Contrary to the expectations of affirmative action skeptics, our results indicate that affirmative action can redistribute both political and economic power without hindering overall development

Strongest model-independent bound on the lifetime of Dark Matter

Dark Matter is essential for structure formation in the late Universe so it must be stable on cosmological time scales. But how stable exactly? Only assuming decays into relativistic particles, we report an otherwise model independent bound on the lifetime of Dark Matter using current cosmological data. Since these decays affect only the low-$\ell$ multipoles of the CMB, the Dark Matter lifetime is expected to correlate with the tensor-to-scalar ratio $r$ as well as curvature $\Omega_k$. We consider two models, including $r$ and $r+\Omega_k$ respectively, versus data from Planck, WMAP, WiggleZ and Baryon Acoustic Oscillations, with or without the BICEP2 data (if interpreted in terms of primordial gravitational waves). This results in a lower bound on the lifetime of CDM given by 160Gyr (without BICEP2) or 200Gyr (with BICEP2) at 95% confidence level.Comment: 15 pages, 5 figures. Prepared for submission to JCA

Évaluation de l’acceptabilité et de l’efficacité potentielle de l’Atelier d’autogestion de la dépression de Revivre. Rapport de recherche.

Ce rapport présente les résultats de l’étude pilote de l’Atelier d’Autogestion de la Dépression (AAD) de Revivre, une intervention de groupe comportant dix séances. Afin d’estimer l’efficacité potentielle de l’AAD, nous avons mesuré les changements survenus chez les participants entre le début et la fin de l’atelier, tant sur le plan de leurs symptômes de dépression que de leur connaissance de la dépression, de leurs comportements d’autogestion, de leur sentiment d’auto-efficacité et de leur adhésion au traitement par antidépresseur. Nous avons également documenté, de manière qualitative, les perceptions des participants et des animateurs quant aux effets de l’atelier, ainsi que leur appréciation de son format, de son contenu, de la formule de groupe et de l’animation.\ud \ud Les résultats indiquent que les symptômes de dépression – mesurés par deux instruments différents – diminuent significativement entre le début et la fin de l’atelier. Cette diminution se poursuit quatre mois plus tard, bien que de façon moins prononcée. Aucune des caractéristiques sociodémographiques (sexe, âge, scolarité, revenu) ou cliniques (sévérité des symptômes au moment de l’entrée dans l’étude, nombre d’épisodes dépressifs antérieurs, prise d’antidépresseurs, psychothérapie au cours de la dernière année, comorbidité physique et psychopathologique) des participants n’influence de manière significative la diminution des symptômes dépressifs. Toutefois, le groupe auquel ils ont participé influence les résultats obtenus.\ud \ud L’AAD a été très apprécié par les participants. Leurs connaissances à propos de la dépression, leur sentiment d’auto-efficacité quant à la gestion de leur dépression et leurs comportements d’autogestion ont augmenté significativement entre le début et la fin de l’atelier. L’atelier ne semble toutefois pas avoir eu d’impact sur l’adhésion au traitement par antidépresseur, qui était déjà élevée au moment de l’entrée dans l’étude. \ud \ud En somme, bien qu’il soit impossible d’attribuer avec certitude les effets observés à l’atelier (en raison de l’absence d’un groupe témoin permettant de contrôler pour l’effet du passage du temps, mais également des entrevues inhérentes au processus de recherche), les résultats obtenus dans le cadre de cette étude pilote sont prometteurs. Ils encouragent à poursuivre la validation de l’atelier et sa diffusion auprès de personnes souffrant de dépression

A Cross-Sectional Survey of the Association between Bilateral Topical Prostaglandin Analogue Use and Ocular Adnexal Features

We studied the relation between prostaglandin analogue use and ocular adnexal features. We used a prospective, cross-sectional study involving 157 current, 15 past, and 171 never users of prostaglandin analogues. Patients 50 years of age or older and without conditions affecting ocular adnexal anatomy underwent glaucoma medication use history, external digital photography and systematic external adnexal exam. Two masked readers assessed the digital photos for upper lid dermatochalasis and lower lid steatoblepharon using a validated grading scheme. Another masked clinical examiner also assessed upper lid ptosis, levator muscle function, and inferior scleral show. We performed ordinal logistic regression analysis accounting for multiple covariates to assess the relation between prostaglandin analogue use and adnexal features. Multivariable analyses indicated there was a 230-fold increased risk of incremental involution of dermatochalasis (odds ratio (OR) = 2.30; 95% confidence interval (CI) 1.43–3.69; p = 5.44E-04) and a 249-fold increased risk of incremental loss of lower lid steatoblepharon (OR = 2.49; 95% CI, 1.54–4.03; p = 1.98E-04) associated with current prostaglandin analogue use (bimatoprost 0.03%, travoprost 0.005%, or latanoprost 0.004%) versus prostaglandin analogue never or past users. Upper lid ptosis (OR = 4.04; 95% CI, 2.43–6.72; p = 7.37E-08), levator dysfunction (OR = 7.51; 95% CI, 3.39–16.65; p = 6.74E-07) and lower lid retraction (OR = 2.60; 95% CI, 1.58–4.28; p = 1.72E-04) were highly associated with current prostaglandin analogue use versus prostaglandin analogue never or past users. The associations between prostaglandin analogue use and deepening of the upper lid sulci and between prostaglandin analogue use and loss of inferior periorbital fat are confirmed in this multivariable analysis. The associations between prostaglandin analogue use and levator muscle dysfunction and between prostaglandin analogue use and upper lid ptosis represent significant side effects that could impact visual function in glaucoma patients

Procedural Adaptations to Avoid Haemodynamic Instability During Catheter Ablation of Scar-related Ventricular Tachycardia

Classically, catheter ablation for scar-related ventricular tachycardia (VT) relied upon activation and entrainment mapping of induced VT. Advances in post-MI therapies have led to VTs that are faster and haemodynamically less stable, because of more heterogeneous myocardial fibrosis patterns. The PAINESD score is one means of identifying patients at highest risk for haemodynamic decompensation during attempted VT induction, who may, therefore, benefit from alternative ablation strategies. One strategy is to use temporary mechanical circulatory support, although this warrants formal assessment of cost-effectiveness. A second strategy is to minimise or avoid VT induction altogether by employing a family of ‘substrate’-based approaches aimed at identifying VT isthmuses during sinus or paced rhythm. Substrate mapping techniques are diverse, and focus on the timing, morphology and amplitude of local ventricular electrograms – sometimes aided by advanced non-invasive cardiac imaging modalities. In this review, the evolution of VT ablation over time is discussed, with an emphasis on procedural adaptations to the challenge of haemodynamic instability

Epidural Blood Patching in Spontaneous Intracranial Hypotension-Do we Really Seal the Leak?

PURPOSE Epidural blood patch (EBP) is a minimally invasive treatment for spontaneous intracranial hypotension (SIH). Follow-up after EBP primarily relies on clinical presentation and data demonstrating successful sealing of the underlying spinal cerebrospinal fluid (CSF) leak are lacking. Our aim was to evaluate the rate of successfully sealed spinal CSF leaks in SIH patients after non-targeted EBP. METHODS Patients with SIH and a confirmed spinal CSF leak who had been treated with non-targeted EBP were retrospectively analyzed. Primary outcome was persistence of CSF leak on spine MRI or intraoperatively. Secondary outcome was change in clinical symptoms after EBP. RESULTS In this study 51 SIH patients (mean age, 47 ± 13 years; 33/51, 65% female) treated with non-targeted EBP (mean, 1.3 EBPs per person; range, 1-4) were analyzed. Overall, 36/51 (71%) patients had a persistent spinal CSF leak after EBP on postinterventional imaging and/or intraoperatively. In a best-case scenario accounting for missing data, the success rate of sealing a spinal CSF leak with an EBP was 29%. Complete or substantial symptom improvement in the short term was reported in 45/51 (88%), and in the long term in 17/51 (33%) patients. CONCLUSION Non-targeted EBP is an effective symptomatic treatment providing short-term relief in a substantial number of SIH patients; however, successful sealing of the underlying spinal CSF leak by EBP is rare, which might explain the high rate of delayed symptom recurrence. The potentially irreversible and severe morbidity associated with long-standing intracranial hypotension supports permanent closure of the leak

The mode of gas accretion onto star-forming galaxies

It is argued that galaxies like ours sustain their star formation by transferring gas from an extensive corona to the star-forming disc. The transfer is effected by the galactic fountain -- cool clouds that are shot up from the plane to kiloparsec heights above the plane. The Kelvin-Helmholtz instability strips gas from these clouds. If the pressure and the the metallicity of the corona are high enough, the stripped gas causes a similar mass of coronal gas to condense in the cloud's wake. Hydrodynamical simulations of cloud-corona interaction are presented. These confirm the existence of a critical ablation rate above which the corona is condensed, and imply that for the likely parameters of the Galactic corona this rate lies near the actual ablation rate of clouds. In external galaxies trails of HI behind individual clouds will not be detectable, although the integrated emission from all such trails should be significant. Parts of the trails of the clouds that make up the Galaxy's fountain should be observable and may account for features in targeted 21-cm observations of individual high-velocity clouds and surveys of Galactic HI emission. Taken in conjunction with the known decline in the availability of cold infall with increasing cosmic time and halo mass, the proposed mechanism offers a promising explanation of the division of galaxies between the blue cloud to the red sequence in the colour-luminosity plane.Comment: 12 pages, 8 figures, 1 table. Accepted for publication in MNRA

Dynamical Evolution of Simulated Particles Ejected from Asteroid Bennu

In early 2019, the OSIRIS‐REx spacecraft discovered small particles being ejected from the surface of the near‐Earth asteroid Bennu. Although they were seen to be ejected at slow speeds, on the order of tens of cm/s, a number of particles were surprisingly seen to orbit for multiple revolutions and days, which requires a dynamical mechanism to quickly and substantially modify the orbit to prevent re‐impact upon their first periapse passage. This paper demonstrates that, based on simulations constrained by the conditions of the observed events, the combined effects of gravity, solar radiation pressure, and thermal radiation pressure from Bennu can produce many sustained orbits for ejected particles. Furthermore, the simulated populations exhibit two interesting phenomena that could play an important role in the geophysical evolution of bodies such as Bennu. First, small particles (<1 cm radius) are preferentially removed from the system, which could lead to a deficit of such particles on the surface. Second, re‐impacting particles preferentially land near or on the equatorial bulge of Bennu. Over time, this can lead to crater in‐filling and growth of the equatorial radius without requiring landslides

Discovery and Functional Annotation of SIX6 Variants in Primary Open-Angle Glaucoma

Glaucoma is a leading cause of blindness worldwide. Primary open-angle glaucoma (POAG) is the most common subtype and is a complex trait with multigenic inheritance. Genome-wide association studies have previously identified a significant association between POAG and the SIX6 locus (rs10483727, odds ratio (OR) = 1.32, p = 3.87×10−11). SIX6 plays a role in ocular development and has been associated with the morphology of the optic nerve. We sequenced the SIX6 coding and regulatory regions in 262 POAG cases and 256 controls and identified six nonsynonymous coding variants, including five rare and one common variant, Asn141His (rs33912345), which was associated significantly with POAG (OR = 1.27, p = 4.2×10−10) in the NEIGHBOR/GLAUGEN datasets. These variants were tested in an in vivo Danio rerio (zebrafish) complementation assay to evaluate ocular metrics such as eye size and optic nerve structure. Five variants, found primarily in POAG cases, were hypomorphic or null, while the sixth variant, found only in controls, was benign. One variant in the SIX6 enhancer increased expression of SIX6 and disrupted its regulation. Finally, to our knowledge for the first time, we have identified a clinical feature in POAG patients that appears to be dependent upon SIX6 genotype: patients who are homozygous for the SIX6 risk allele (His141) have a statistically thinner retinal nerve fiber layer than patients homozygous for the SIX6 non-risk allele (Asn141). Our results, in combination with previous SIX6 work, lead us to hypothesize that SIX6 risk variants disrupt the development of the neural retina, leading to a reduced number of retinal ganglion cells, thereby increasing the risk of glaucoma-associated vision loss