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We model the TESS light curve of the binary system RX Dra, and also first calculate a lot of theoretical models to fit the g-mode frequencies previously detected from the TESS series of this system. The mass ratio is determined to be $q$=0.9026$^{+0.0032}_{-0.0032}$. We newly found that there are 16 frequencies (F1-F7, F11-F20) identified as dipole g-modes, two frequencies (F21, F22) identified as quadrupole g-modes, and another two frequencies (F23, F24) identified as g-sextupole modes, based on these model fits. The primary star is newly determined to be a $\gamma$ Dor pulsator in the main-sequence stage with a rotation period of about 5.7$^{+0.7}_{-0.2}$ days, rotating slower than the orbital motion. The fundamental parameters of two components are firstly estimated as follows: $M_1$=1.53$^{+0.00}_{-0.17}$ M $_{\odot}$, $M_2$= 1.38$^{+0.18}_{-0.00}$ M $_{\odot}$, $T_1$=7240$^{+490}_{-44}$ K, $T_2$=6747$^{+201}_{-221}$ K, $R_1$=1.8288$^{+0.0260}_{-0.0959}$ R $_{\odot}$, $R_2$= 1.3075$^{+0.0450}_{-0.2543}$ R $_{\odot}$, $L_1$=8.2830$^{+1.8015}_{-0.6036}$ L $_{\odot}$ and $L_2$= 3.4145$^{+0.1320}_{-0.1843}$ L $_{\odot}$. Our results show that the secondary star is in the solar-like pulsator region of the H-R diagram, indicating that it could be a pulsating star of this type. Finally, the radius of the convective core of the primary star is estimated to be about 0.1403$^{+0.0206}_{-0.0000}$ R$_{\odot}$., Comment: 13 pages,7 figures

Numerous delta Sct and gamma Dor pulsators are identified in the region of the Hertzsprung-Russell diagram that is occupied by chemically peculiar magnetic Ap stars. The connection between delta Sct and gamma Dor pulsations and the magnetic field in Ap stars is however not clear: theory suggests for magnetic Ap stars some critical field strengths for pulsation mode suppression by computing the magnetic damping effect for selected p and g modes. To test these theoretical considerations, we obtained PEPSI spectropolarimetric snapshots of the typical Ap star HD340577, for which delta Sct-like pulsations were recently detected in TESS data, and the gamma Dor pulsator HR8799, which is a remarkable system with multiple planets and two debris disks. Our measurements reveal the presence of a magnetic field with a strength of several hundred Gauss in HD340577. The measured mean longitudinal field would be the strongest field measured so far in a delta Sct star if the pulsational character of HD340577 is confirmed spectroscopically. No magnetic field is detected in HR8799., Comment: 5 pages, 4 figures, accepted for publication as a letter to MNRAS

Many complex and disordered systems fail to reach equilibrium after they have been quenched or perturbed. Instead, they sluggishly relax toward equilibrium at an ever-slowing, history-dependent rate, a process termed physical aging. The microscopic processes underlying the dynamic slow-down during aging and the reason for its similar occurrence in different systems remain poorly understood. Here, we reveal the structural mechanism underlying logarithmic aging in disordered mechanical systems, through experiments in crumpled sheets and simulations of a disordered network of bi-stable elastic elements. We show that under load, the system self-organizes to a metastable state poised on the verge of an instability, where it can remain for long, but finite times. The system's relaxation is intermittent, advancing via rapid sequences of instabilities, grouped into self-similar, aging avalanches. Crucially, the quiescent dwell times between avalanches grow in proportion to the system's age, due to a slow increase of the lowest effective energy barrier, which leads to logarithmic aging., Comment: 7 pages, 3 figures

Ordered mechanical systems typically have one or only a few stable rest configurations, and hence are not considered useful for encoding memory. Multistable and history-dependent responses usually emerge from quenched disorder, for example in amorphous solids or crumpled sheets. In contrast, due to geometric frustration, periodic magnetic systems can create their own disorder and espouse an extensive manifold of quasi-degenerate configurations. Inspired by the topological structure of frustrated artificial spin ices, we introduce an approach to design ordered, periodic mechanical metamaterials that exhibit an extensive set of spatially disordered states. While our design exploits the correspondence between frustration in magnetism and incompatibility in meta-mechanics, our mechanical systems encompass continuous degrees of freedom, and are hence richer than their magnetic counterparts. We show how such systems exhibit non-Abelian and history-dependent responses, as their state can depend on the order in which external manipulations were applied. We demonstrate how this richness of the dynamics enables to recognize, from a static measurement of the final state, the sequence of operations that an extended system underwent. Thus, multistability and potential to perform computation emerge from geometric frustration in ordered mechanical lattices that create their own disorder., Comment: Supplementarey video: https://youtu.be/9FKM54Lb5gU

Random integers, sampled uniformly from $[1,x]$, share similarities with random permutations, sampled uniformly from $S_n$. These similarities include the Erd\H{o}s--Kac theorem on the distribution of the number of prime factors of a random integer, and Billingsley's theorem on the largest prime factors of a random integer. In this paper we extend this analogy to non-uniform distributions. Given a multiplicative function $\alpha \colon \mathbb{N} \to \mathbb{R}_{\ge 0}$, one may associate with it a measure on the integers in $[1,x]$, where $n$ is sampled with probability proportional to the value $\alpha(n)$. Analogously, given a sequence $\{ \theta_i\}_{i \ge 1}$ of non-negative reals, one may associate with it a measure on $S_n$ that assigns to a permutation a probability proportional to a product of weights over the cycles of the permutation. This measure is known as the generalized Ewens measure. We study the case where the mean value of $\alpha$ over primes tends to some positive $\theta$, as well as the weights $\alpha(p) \approx (\log p)^{\gamma}$. In both cases, we obtain results in the integer setting which are in agreement with those in the permutation setting., Comment: 29 pages. Journal version

Whereas Natural User Interface technological devices, such as tablets, are bringing physical interaction back into mathematics learning activities, existing educational theory is not geared to inform or interpret such learning. In particular, educational researchers investigating instructional interactions still need intellectual and methodological frameworks for conceptualizing, designing, facilitating, and analyzing how students' immersive hands-on dynamical experiences become formulated within semiotic registers typical of mathematical discourse. We present paradigmatic empirical examples of tutor-student behaviors in an embodied-interaction learning environment, the Mathematical Imagery Trainer for Proportion. Drawing on ecological dynamics--a blend of dynamical-systems theory and ecological psychology--we describe the emergence of mathematical concepts from the guided discovery of sensorimotor schemes. [For the complete proceedings, see ED583989.]

Focusing on the pedagogy curriculum of teacher education colleges in Israel, this study examines the influences of various curriculum factors actually implemented in the classroom as compared with noncurriculum factors. Data from 269 education students affirms the positive contribution of curriculum factors. (SLD)

Duration of response (DOR) and time to response (TTR) are typically evaluated as secondary endpoints in early-stage clinical studies in oncology when efficacy is assessed by the best overall response (BOR) and presented as the overall response rate (ORR). Despite common use of DOR and TTR in particular in single-arm studies, the definition of these endpoints and the questions they are intended to answer remain unclear. Motivated by the estimand framework, we present relevant scientific questions of interest for DOR and TTR and propose corresponding estimand definitions. We elaborate on how to deal with relevant intercurrent events which should follow the same considerations as implemented for the primary response estimand. A case study in mantle cell lymphoma illustrates the implementation of relevant estimands of DOR and TTR. We close the paper with practical recommendations to implement DOR and TTR in clinical study protocols.

The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of 100 billion electron volts for a deep exposure of 210 hours. Three sources of different types were detected: the pulsar wind nebula of the most energetic pulsar known N 157B, the radio-loud supernova remnant N 132D and the largest non-thermal X-ray shell - the superbubble 30 Dor C. The unique object SN 1987A is, surprisingly, not detected, which constrains the theoretical framework of particle acceleration in very young supernova remnants. These detections reveal the most energetic tip of a gamma-ray source population in an external galaxy, and provide via 30 Dor C the unambiguous detection of gamma-ray emission from a superbubble., Comment: Published in Science Magazine (Jan. 23, 2015). This ArXiv version has the supplementary online material incorporated as an appendix to the main paper

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Issue: The Affordable Care Act's individual mandate requires most Americans to enroll in health insurance. In 2017, Congress eliminated financial penalties associated with failing to comply with the mandate, which becomes effective in 2019. Goal: To review the evidence for how individual mandates affect enrollment decisions, and to assess the effect of eliminating the penalty on enrollment, premiums, and the federal deficit. Methods: We reviewed the literature on health insurance mandates and conducted analysis using the RAND COMPARE microsimulation model. Findings and Conclusions: Consumers' responses to mandates may be influenced by nonfinancial factors that are difficult to measure, including a desire to comply with the law, beliefs about enforcement, and inertia in decisionmaking. Under a range of scenarios that reflect alternative assumptions about responses to these factors, we find that enrollment falls by 2.8 million to 13 million people and premiums for bronze plans increase by 3 percent to 13 percent when the mandate penalty is removed. The impact on the federal budget deficit is more uncertain, with effects ranging from a reduction of $8 billion to an increase of $3.6 billion in 2020. The effect on the deficit depends on how enrollees who are eligible for tax credits and Medicaid -- those who have little financial reason to drop coverage -- respond to the penalty's elimination. [ABSTRACT FROM AUTHOR]

Discusses teaching English in Toronto, Ontario, Canada, where the majority of students have acquired English as an additional language. Suggests that teaching English in these classes presents rewarding and frustrating challenges--challenges which are at least as rewarding and frustrating for students as they are for teachers. Describes the ESL Writers Online and the "DOR-WEST" projects. (RS)

While the longest expansion ever recorded is now history, the improvements in many areas of economic performance that accompanied it remain intact. The tight labour market together with robust gains [...]

The US health care system is unique in the OECD area. It does not have a national insurance programme and 14 per cent of the population has no insurance coverage, [...]

Skilful policy actions limited the extent and duration of last year's economic downturn. A rapid monetary easing -- both before and after the events of 11 September -- combined with [...]

After a short and shallow recession... The US economy entered recession in the first half of 2001, with employment falling and industrial production continuing the slide it had begun in [...]