Multicolour photometry of Balloon 090100001: linking the two classes of pulsating hot subdwarfs

We present results of the multicolour UBVR photometry of the high-amplitude EC14026-type star, Balloon 090100001. The data span over a month and consist of more than a hundred hours of observations. Fourier analysis of these data led us to the detection of at least 30 modes of pulsation of which 22 are independent. The frequencies of 13 detected modes group in three narrow ranges, around 2.8, 3.8 and 4.7 mHz, where the radial fundamental mode, the first and second overtones are likely to occur. Surprisingly, we also detect 9 independent modes in the low-frequency domain, between 0.15 and 0.4 mHz. These modes are typical for pulsations found in PG1716+426-type stars, discovered recently among cool B-type subdwarfs. The modes found in these stars are attributed to the high-order g modes. As both kinds of pulsations are observed in Balloon 090100001, it represents a link between the two classes of pulsating hot subdwarfs. At present, it is probably the most suitable target for testing evolutionary scenarios and internal constitution models of these stars by means of asteroseismology. Three of the modes we discovered form an equidistant frequency triplet which can be explained by invoking rotational splitting of an $\ell$ = 1 mode. The splitting amounts to about 1.58 $\mu$Hz, leading to a rotation period of 7.1 $\pm$ 0.1 days.Comment: 12 pages, 14 figures, accepted for publication in MNRAS. For full-resolution postscript file, visit http://www.as.wsp.krakow.pl/~andy/balloon.ps.g

Evidence of a new low field cross-over in the vortex critical velocity of type-II superconducting thin films

We measure current-voltage characteristics as function of magnetic field and temperature in Nb strips of different thickness and width. The instability voltage of the flux flow state related to the vortex critical velocity v* is studied and compared with the Larkin-Ovchinnikov theory. Beside the usual power-law dependence v* ~ B^-1/2, in the low field range a new cross-over field, Bcr1, is observed below which v* decreases by further lowering the external magnetic field B. We ascribe this unexpected cross-over to vortex channeling due to a fan-like penetration of the applied magnetic field as confirmed by magneto-optic imaging. The observation of Bcr1 becomes a direct evidence of a general feature in type-II superconducting films at low fields, that is a channel-like vortex motion induced by the inhomogeneous magnetic state caused by the relatively strong pinning

Une épitaphe aux discours d’austérité? Une approche expérimentale des évolutions de l’opinion publique et des dynamiques de classe pendant la crise de la Covid-19

The Covid-19 pandemic is disrupting the international political economy context unlike any event since World War II. As a consequence, the French government has, at least momentarily, reversed decades of fiscal consolidation policies sedimented around austerity narratives by instating a costly emergency furlough scheme for a third of the workforce. This crisis provides a natural setting to investigate the relations among an emerging “critical juncture” in political economy, public preferences, and the salience of austerity narratives. We collected panel data and administered two experiments to test if citizens’ viewpoints are sensitive to the trade-off between health and economics, still receptive to austerity narratives, and conditioned by socioeconomic status in supporting them. We find public viewpoints were highly swayable between health and economic concerns at the first peak of the epidemic outbreak in April 2020, but they were not influenced by the austerity narratives during the phase-out of the lockdown in June, with the exception of the upper class. Overall, public support is shifting in favor of increased social spending, and austerity might no longer inhabit the majority’s “common sense.” We conclude with further implications for the study of class and conflict in a post-pandemic world.La pandémie de Covid-19 bouleverse le contexte de l’économie politique internationale comme aucun événement ne l’a fait depuis la Seconde Guerre mondiale. En conséquence, le gouvernement français a, au moins momentanément, foulé au pied des décennies de politiques d’assainissement budgétaire appuyées sur des discours d’austérité, en mettant en place une aide d’urgence onéreuse à destination d’un tiers de la population active. Cette crise offre donc un cadre naturel pour enquêter sur les relations entre ce «moment critique» émergent de l’économie politique, l’opinion publique et la prépondérance du récit justifiant les mesures d’austérité. Nous avons collecté des données auprès d’un panel et mené deux expériences pour tester si les points de vue exprimés par les citoyens sont sensibles au compromis entre mesures privilégiant la santé ou l’économie, s’ils se montrent toujours réceptifs aux récits d’austérité et si leur soutien est conditionné par leur statut socio-économique. Nous avons pu constater que si les points de vue exprimés lors du premier pic épidémique d’avril 2020 oscillaient aisément des préoccupations sanitaires aux préoccupations économiques, ils n’étaient plus perméables aux discours d’austérité lors de la sortie progressive du confinement en juin, à l’exception de la classe supérieure. Dans l’ensemble, le soutien du public semble basculer en faveur d’une augmentation des dépenses sociales et l’austérité ne plus appartenir au «sens commun» de la majorité de la population. Nous concluons avec des implications pour l’étude des classes sociales et des conflits dans un monde post-pandémique.1 Introduction 2 Contextualizing public opinion shifts in political economy 3 Measuring public preferences and their manipulability 4 Moving away from austerity narratives? For the many, not the few 5 Concluding remarks 6 Data and methodological note Reference

Tandem Fan Applications in Advanced STOVL Fighter Configurations

The series/parallel tandem fan engine is evaluated for application in advanced STOVL supersonic fighter aircraft. Options in engine cycle parameters and design of the front fan flow diverter are examined for their effects on engine weight, dimensions, and other factors in integration of the engine with the aircraft. Operation of the engine in high-bypass flow mode during cruise and loiter flight is considered as a means of minimizizng fuel consumption. Engine thrust augmentation by burning in the front fan exhaust is discussed. Achievement of very sort takeoff with vectored thrust in briefly reviewed for tandem fan engine configurations with vectorable front fan nozzles. Examples are given of two aircraft configuration planforms, a delta-canard, and a forward-swept wing, to illustrate the major features. design considerations, and potential performance of the tandem fan installation in each. Full realization of the advantages of tandem fan propulsion are found to depend on careful selection of the aircraft configuration, since integration requirements can strongly influence the engine performance

Interview with Zola Houghton

An interview with Zola Houghton regarding her experiences in a one-room school house.https://scholars.fhsu.edu/ors/1031/thumbnail.jp

Two-year outcome of an observe-and-plan regimen for neovascular age-related macular degeneration treated with Aflibercept.

The purpose of our study was to investigate the two-year outcome of Aflibercept treatment for neovascular age-related macular degeneration (nAMD), using the Observe-and-Plan regimen, an individually planned treatment regimen, based on the predictability of an individual's need for retreatment, aiming to reduce the clinical burden. Our prospective study used the Observe-and-Plan regimen with Aflibercept to treat nAMD: Three loading doses, followed by monthly observation visits until the disease-recurrence interval was determined, which then was shortened by 2 weeks in a treatment plan for the next three injections without intermediate monitoring visits. The subsequent treatment plans were adjusted according to periodically assessed disease activity. The primary outcome measures were visual acuity changes, number of injections, and number of monitoring visits. The study included 112 eyes of 102 patients with a mean age of 80.7 years (SD 7.6). Mean visual acuity (VA) improved from 61.8 ETDRS letters (20/60(+2)) at baseline, by 8.5, 8.0, and 6.2 letters at months 3, 12 and 24, respectively. Mean central retinal thickness was 438um at baseline, and reduced by 152um, 155um, and 150um at months 3, 12 and 24, respectively. The mean number of injections was 8.7 and 6.5 in the first and second year, respectively. The mean number of monitoring visits after baseline was 3.8 and 2.8 during the first and second year, respectively. The Observe-and-Plan regimen significantly improved VA, while fewer monitoring visits were needed as compared to other variable dosing regimens, thus reducing the workload for chronic care management of nAMD

Photometric, Spectroscopic and Orbital Period Study of Three Early Type Semi-detached Systems: XZ Aql, UX Her and AT Peg

In this paper we present a combined photometric, spectroscopic and orbital period study of three early-type eclipsing binary systems: XZ Aql, UX Her, and AT Peg. As a result, we have derived the absolute parameters of their components and, on that basis, we discuss their evolutionary states. Furthermore, we compare their parameters with those of other binary systems and with the theoretical models. An analysis of all available up-to-date times of minima indicated that all three systems studied here show cyclic orbital changes, their origin is discussed in detail. Finally, we performed a frequency analysis for possible pulsational behavior and as a result we suggest that XZ Aql hosts a {\delta} Scuti component.Comment: 40 pages, 16 figure

Time-domain behavior of blazar OJ 287 and the binary supermassive black hole conjecture

The proper understanding of blazar variability at the various electromagnetic spectral bands is one goal of multifrequency astrophysics. In this frame a peculiar and controversial phenomenology is the periodicity, postulated for long-term radio or optical flux light curves of about a dozen of blazars. The well-known BL Lac object OJ 287 (PKS 0851+202, S3 0851+20, PG 0851+202, z = 0.306) is not only a high-variable, peculiar, extragalactic source with hints for approximatively cyclical optical outbursts, but it also represents a case of substantial intensive and extensive (long-term) multifrequency observations. This rich database allow us a deeper analysis based on a wide range of variability timescales with some recent results that are highlighted here. © Copyright owned by the author(s).Peer reviewe