The binding energy produced within the framework of the accretion of millisecond pulsars

The role and implication of binding energy through the accretion-induced collapse (AIC) of accreting white dwarfs (WDs) for the production of millisecond pulsars (MSPs) are investigated. I examine the binding energy model due to the dynamical process in close binary systems and investigating the possible mass of the companion sufficient to induce their orbital parameters. The deterministic nature of this interaction has a strong sensitivity to the equation of state of the binary systems (where the compactness of a neutron star is proportional to the amount of binding energy) associated with their initial conditions. This behavior will mimic the commonly assumed mass and amount of accreted matter under the instantaneous mass loss ($\Delta M \sim 0.18M_{\odot}$). As a result, this will indicate an increase in the MSP's gravitational mass due to angular momentum losses. The outcome of such a system will then be a circular binary MSP in which the companion is a low-mass WD, thus distinguishing the binary formation scenarios. In addition, the results of this work could provide constraints on the expected mass and binding energy of a neutron star based on the accretion rat

Cognitive and Psychosocial Factors Associated with Sarcopenia in Older Adults

Objectives: To describe the muscle mass, strength, and function of older adults living in residential care apartment complexes (RCACs) and examine the association between self-efficacy for exercise, depressive symptoms, social support and sarcopenia. The convergent validity of Muscle Mechanography (MM) when compared to the traditional muscle function and strength tests was also tested. Design: Secondary data analysis of baseline data from a clinical trial. Setting: One RCAC in the Midwestern United States. Participants: Thirty-one older adults living in one RCAC. Measurement: Muscle mass was measured by bioelectrical impedance spectroscopy. Muscle function was evaluated by the Short Physical Performance Battery test, Timed Up and Go test, and MM. Grip strength was measured by a Jamar® hand dynamometer. Self-efficacy for exercise was measured by the Self-efficacy for Exercise Scale. Depressive symptoms were measured by the Geriatric Depression Scale. Social support was measured by the Lubben Social Network Scale. Results: Participants had lower values of muscle mass, strength, and function compared to values obtained in previous research. A sex difference exists for muscle mass, strength, and function. The findings showed a trend for individuals with high self-efficacy, without depressive symptoms, and with strong social support to present greater muscle mass, strength, and function. The findings also demonstrated convergent validity across all the examined measures of muscle function and strength. Conclusion: This study is only one of a few to describe the muscle outcomes and evaluate the relationship between selected cognitive and psychosocial factors and sarcopenia among older adults living in RCACs. The preliminary findings of this study warrant further investigation of an intervention aimed at maintaining or improving the muscle outcomes of RCAC residents. While the interpretation of findings should be presented with caution and replicated with other samples, this study may provide a new understanding about the muscle outcomes and the relationship between self-efficacy for exercise, depressive symptoms, and social support and sarcopenia. Improved understanding of muscle outcomes and the relationship between cognitive and psychosocial factors and sarcopenia is crucial. The findings also provided a new evidence about MM as a new technology to quantitively assess muscle function in older adults, potentially making this a valuable research tool

Quiescent photometric modulations of two low-inclination cataclysmic variables KZGem and TWVir

The quiescent periodic photometric modulations of two low-inclination cataclysmic variables observed in Kepler K2 Campaigns 0 and 1, KZ Gem and TW Vir, are investigated. A phase-correcting method was successfully used to detect the orbital modulations of KZ Gem and TW Vir and improve their orbital periods. The light curve morphologies of both CVs were further analyzed by defining flux ratios and creating colormaps. KZ Gem shows ellipsoidal modulations with an orbital period of 0.22242(1) day, twice the period listed in the updated RK catalogue (Edition 7.24). With this newly determined period, KZ Gem is no longer a CV in the period gap, but a long-period CV. A part of the quiescent light curve of TW Vir that had the highest stability was used to deduce its improved orbital period of 0.182682(3) day. The flat patterns shown in the colormaps of the flux ratios for KZ Gem demonstrate the stability of their orbital modulations, while TW Vir show variable orbital modulations during the K2 datasets. In TW Vir, the single versus double-peaked nature of the quiescent orbital variations before and after superoutburst may be related to the effect of the superoutburst on the accretion disk.Comment: 10 pages, 12 figures, accepted by A&

Speckle-interferometric study of close visual binary system Hip 11253 (HD14874) using Gaia (DR2) and (EDR3)

We present a comprehensive set of physical and geometrical parameters for each of the components of the close visual binary system Hip 11253 (HD14874). We present an analysis for the binary and multiple stellar systems with the aim to obtain a match between the overall observational spectral energy distribution of the system and the spectral synthesis created from model atmospheres. The epoch positions are used to determine the orbital parameters and the total mass.Comment: Accepted for publication in Research in Astronomy and Astrophysics (RAA