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We present an update on the variable star survey performed on the TESS 30 min Full Frame Image (FFI) data reported by our first two papers in this series. This update includes a contamination analysis in order to identify false positives and analysis of the TESS 10 min FFI data collected during Years 3 and 4 of the mission. We clarify the variability status of 2 995 targets identifying 1 403 variable stars. In addition, we spectroscopically classify 24 pre-filtered targets sampled with the 10 min FFI data and discover 11 new sdB pulsators. Future follow-up space- and/or ground-based data of variables reported here, to identify the nature of their variability and reveal spectroscopic parameters of the stars, would complement this work. [ABSTRACT FROM AUTHOR]

We present new time-resolved photometry for two sdB stars, and , which clearly shows them to be rapidly pulsating stars of the “EC14026” class. In we detect, with some confidence, seven frequencies between 5252 and 9368 μHz corresponding to periods between 190 and 107 s. In , for which our data are much sparser, we identify only a single frequency near 6090 μHz (164 s). New spectroscopy, combined with archival (2MASS) infrared photometry, indicates that has a companion of spectral type near G0V–G2V, whilst has a companion of later spectral type, probably in the range G5V–K5V. [Copyright &y& Elsevier]

EPIC 216747137 is a new HW Virginis system discovered by the Kepler spacecraft during its K 2 'second life'. Like the other HW Vir systems, EPIC 216747137 is a post-common-envelope eclipsing binary consisting of a hot subluminous star and a cool low-mass companion. The short orbital period of 3.87 h produces a strong reflection effect from the secondary (∼9 per cent in the R band). Together with AA Dor and V1828 Aql, EPIC 216747137 belongs to a small subgroup of HW Vir systems with a hot evolved sdOB primary. We find the following atmospheric parameters for the hot component: T eff = 40400 ± 1000 K, log  g  = 5.56 ± 0.06, and log(N (He)/ N (H)) = −2.59 ± 0.05. The sdOB rotational velocity v  sin   i  = 51 ± 10 km s−1 implies that the stellar rotation is slower than the orbital revolution and the system is not synchronized. When we combine photometric and spectroscopic results with the Gaia parallax, the best solution for the system corresponds to a primary with a mass of about 0.62 M⊙ close to, and likely beyond, the central helium exhaustion, while the cool M-dwarf companion has a mass of about 0.11 M⊙. [ABSTRACT FROM AUTHOR]

We present phase-resolved optical spectroscopy of the eclipsing nova-like cataclysmic variable EC 21178−5417 obtained between 2002 and 2013. The average spectrum of EC 21178−5417 shows broad double-peaked emission lines from He  ii 4686 Å (strongest feature) and the Balmer series. The high-excitation feature, C  iii /N  iii at 4640–4650 Å, is also present and appears broad in emission. A number of other lines, mostly He  i , are clearly present in absorption and/or emission. The average spectrum of EC 21178−5417 taken at different months and years shows variability in spectral features, especially in the Balmer lines beyond Hγ, from pure line emission, mixed line absorption, and emission to pure absorption lines. Doppler maps of the He  ii 4686 Å emission reveal the presence of a highly inclined asymmetric accretion disc and a two spiral arm-like structure, whereas that of the Balmer lines (Hα and Hβ) reveal a more circular accretion disc. There is no evidence of a bright-spot in the Doppler maps of EC 21178−5417 and no emission from the secondary star is seen in the tomograms of the He  ii 4686 Å and Balmer lines. Generally, the emission in EC 21178−5417 is dominated by emission from the accretion disc. We conclude that EC 21178−5417 is a member of the RW Tri or UX UMa subtype of nova-like variables based on these results and because it shows different spectral characteristics at different dates. This spectral behaviour suggests that EC 21178−5417 undergoes distinct variations in mass transfer rate on the observed time-scales of months and years. [ABSTRACT FROM AUTHOR]

We analysed recent K2 data of the short-period eclipsing binary system HW Vir, which consists of a hot subdwarf-B type primary with an M-dwarf companion. We determined the mid-times of eclipses, calculated O–C diagrams, and an average shift of the secondary minimum. Our results show that the orbital period is stable within the errors over the course of the 70 days of observations. Interestingly, the offset from mid-orbital phase between the primary and the secondary eclipses is found to be 1.62 s. If the shift is explained solely by light-travel time, the mass of the sdB primary must be 0.26 M⊙, which is too low for the star to be core-helium burning. However, we argue that this result is unlikely to be correct and that a number of effects caused by the relative sizes of the stars conspire to reduce the effective light-travel time measurement. After removing the flux variation caused by the orbit, we calculated the amplitude spectrum to search for pulsations. The spectrum clearly shows periodic signal from close to the orbital frequency up to 4600 µHz, with the majority of peaks found below 2600 µHz. The amplitudes are below 0.1 part-per-thousand, too low to be detected with ground-based photometry. Thus, the high-precision data from the Kepler spacecraft has revealed that the primary of the HW Vir system is a pulsating sdBV star. We argue that the pulsation spectrum of the primary in HW Vir differs from that in other sdB stars due to its relatively fast rotation that is (nearly) phase-locked with the orbit. [ABSTRACT FROM AUTHOR]

Scientific evidence is quickly growing that establishes FGF21 as a cytokine that signals both locally and systemically to induce metabolic effects. The focus of this chapter is the receptor/co-receptor signaling complex formed by endocrine FGF21. We provide an introduction to the major components of the complex including the Klotho family of co-receptors, fibroblast growth factor receptors (FGFRs), and the fibroblast growth factor ligands, placing each in the context of its own family members while emphasizing structural features that drive interaction. We subsequently focus specifically on FGF21 signaling through FGFR1c and KLB, describing what is known about each protein's structure and how this drives protein interaction and formation of the signaling complex at the plasma membrane. We subsequently explore the stoichiometry of FGFR1c and KLB at the plasma membrane before and after the addition of FGF21 ligand, comparing how unique features of the interaction could potentially affect signaling intensity. Finally, we discuss how formation of the signaling complex is potentially regulated by other regulatory interactions, including galectins, the extracellular matrix, and co-expression of FGFR5., (© 2016 Elsevier Inc. All rights reserved.)

CMF1 protein is expressed in developing striated muscle before the expression of contractile proteins, and depletion of CMF1 in myoblasts results in inability to express muscle-specific proteins. Previous studies of CMF1 identify a functional Rb-binding domain, which is conserved in the murine and human homologues. Here, we show that CMF1 binds Rb family members, while a CMF1 protein with deletion of the Rb-binding domain (Rb-del CMF1) does not. Myogenic cell lines over-expressing Rb-del CMF1 proliferate normally, but exhibit markedly impaired differentiation, including dramatically reduced contractile proteins gene expression and failure to fuse into myotubes. Furthermore, by quantitative real-time polymerase chain reaction, MyoD and Myf5 mRNA levels are comparable to wild-type, while myogenin and contractile protein mRNA levels are significantly attenuated. These data demonstrate that CMF1 regulates myocyte differentiation by interaction with Rb family members to induce expression of myogenic regulatory factors.