Intense CIII] 1907,1909 emission from a strong Lyman continuum emitting galaxy

We have obtained the first complete ultraviolet (UV) spectrum of a strong Lyman continuum(LyC) emitter at low redshift -- the compact, low-metallicity, star-forming galaxy J1154+2443 -- with a Lyman continuum escape fraction of 46% discovered recently. The Space Telescope Imaging Spectrograph spectrum shows strong Lya and CIII] 1909 emission, as well as OIII] 1666. Our observations show that strong LyC emitters can have UV emission lines with a high equivalent width (e.g. EW(CIII])$=11.7 \pm 2.9 \AA$ rest-frame), although their equivalent widths should be reduced due to the loss of ionizing photons. The intrinsic ionizing photon production efficiency of J1154+2443 is high, $\log(\xi_{\rm ion}^0)=25.56$ erg$^{-1}$ Hz, comparable to that of other recently discovered $z \sim 0.3-0.4$ LyC emitters. Combining our measurements and earlier determinations from the literature, we find a trend of increasing $\xi_{\rm ion}^0$ with increasing CIII] 1909 equivalent width, which can be understood by a combination of decreasing stellar population age and metallicity. Simple ionization and density-bounded photoionization models can explain the main observational features including the UV spectrum of J1154+2443.Comment: 5 pages, 4 figures. Accepted for publication in A&A Letter

Local cosmic string in generalised scalar tensor theory

A recent investigation shows that a local gauge string with a phenomenological energy momentum tensor, as prescribed by Vilenkin, is inconsistent in Brans-Dicke theory. In this work it has been shown that such a string is consistent in a more general scalar tensor theory where $\omega$ is function of the scalar field.A set of solutions of full nonlinear Einstein's equations for interior region of such a string are presented.Comment: 7 pages, latex format, minor changes according to referee's suggestions, revised version submitted in Phys.Rev.

Understanding stellar activity-induced radial velocity jitter using simultaneous K2 photometry and HARPS RV measurements

One of the best ways to improve our understanding of the stellar activity-induced signal in radial velocity (RV) measurements is through simultaneous high-precision photometric and RV observations. This is of prime importance to mitigate the RV signal induced by stellar activity and therefore unveil the presence of low-mass exoplanets. The K2 Campaign 7 and 8 field-of-views were located in the southern hemisphere, and provided a unique opportunity to gather unprecedented simultaneous high precision photometric observation with K2 and high-precision RV measurements with the HARPS spectrograph to study the relationship between photometric variability and RV jitter. We observed nine stars with different levels of activity; from quiet to very active. We probe the presence of any meaningful relation between measured RV jitter and the simultaneous photometric variation, and also other activity indicators (e.g. BIS, FWHM, $logR'_{HK}$, and F8), by evaluating the strength and significance of the correlation between RVs and each indicator. We found that for the case of very active stars, strong and significant correlations exist between almost all the observables and measured RVs; however, for lower activity levels the correlations become random. Except for the F8 which its strong correlation with RV jitter persists over a wide range of stellar activity level, and thus our result suggests that F8 might be a powerful proxy for activity induced RV jitter. Moreover, we examine the capability of two state-of-the-art modeling techniques, namely the FF' method and SOAP2.0, in accurately predicting the RV jitter amplitude using the simultaneous photometric observation. We found that for the very active stars both techniques can reasonably well predict the amplitude of the RV jitter, however, at lower activity levels the FF' method underpredicts the RV jitter amplitude.Comment: 13 pages, 7 figures, 2 tables, accepted for publication in A&

A VEL3 histone deacetylase complex establishes a maternal epigenetic state controlling progeny seed dormancy

Mother plants play an important role in the control of dormancy and dispersal characters of their progeny. In Arabidopsis seed dormancy is imposed by the embryo-surrounding tissues of the endosperm and seed coat. Here we show that VERNALIZATION5/VIN3-LIKE 3 (VEL3) maintains maternal control over progeny seed dormancy. Acting early in endosperm development, it establishes an epigenetic state that primes the depth of primary seed dormancy that will be reached later during seed maturation. VEL3 relocates MSI1 to the nucleolus and associates with other components of the histone deacetylase complex (HDAC). Furthermore VEL3 preferentially associates with pericentromeric chromatin and is required for deacetylation and H3K27me3 deposition in the central cell. Interestingly, the epigenetic state established by the maternal VEL3 is retained in mature seeds, and controls seed dormancy in part through the repression of programmed cell death-associated gene ORE1. Our data demonstrates a novel mechanism by which maternal control of progeny seed physiology persists post-shedding, maintaining parental control of seed behaviour

Noise Sources in Photometry and Radial Velocities

The quest for Earth-like, extrasolar planets (exoplanets), especially those located inside the habitable zone of their host stars, requires techniques sensitive enough to detect the faint signals produced by those planets. The radial velocity (RV) and photometric transit methods are the most widely used and also the most efficient methods for detecting and characterizing exoplanets. However, presence of astrophysical "noise" makes it difficult to detect and accurately characterize exoplanets. It is important to note that the amplitude of such astrophysical noise is larger than both the signal of Earth-like exoplanets and state-of-the-art instrumentation limit precision, making this a pressing topic that needs to be addressed. In this chapter, I present a general review of the main sources of noise in photometric and RV observations, namely, stellar oscillations, granulation, and magnetic activity. Moreover, for each noise source I discuss the techniques and observational strategies which allow us to mitigate their impact.Comment: 11 pages, 2 tables, Lecture presented at the IVth Azores International Advanced School in Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in July 201

The hammock: a reservoir of allergens

INTRODUCTION: Asthma affects approximately 10% of the world's population. Sensitization to allergens is an important risk factor, and exposure to allergens is associated with disease severity. METHODS: We performed skin tests to evaluate allergen sensitization to mites, cockroaches, cats, dogs, and molds in 73 asthmatic patients. Enzyme Linked Immunosorbent Assay was used to assay the mite and cockroach allergens found in dust from the bedding, hammocks, bedroom floors, living rooms, and kitchens of 29 patients and 14 controls. RESULTS: Fifty patients (68.5%) had positive skin test responses. There were positive responses to D. pteronyssinus (52.0%), B. tropicalis (53.4%), T. putrescentiae (15.0%), E. maynei (12.3%), L. destructor (8.2%), B. germanica (20.5%), P. americana (21.9%), Felis catus (10.9%), C. herbarium (2.7%), A. alternata (4.1%), and P. notatun (1.3%). The exposure to mite and cockroach allergens was similar in the patients and the controls. The Dermatophagoides pteronyssinus Group 1 levels were highest in the beds and hammocks. The Blattella germanica Group 1 levels were highest in the kitchens, living rooms and hammocks. DISCUSSION: The positive skin tests to mites, cockroaches and cats were consistent with previous studies. D pteronyssinus was the most prevalent home dust mite, and hammocks were a source of allergens. To improve asthma prophylaxis, it is important to determine its association with mite allergen exposure in hammocks

TMEM59 defines a novel ATG16L1-binding motif that promotes local activation of LC3

Selective autophagy underlies many of the important physiological roles that autophagy plays in multicellular organisms, but the mechanisms involved in cargo selection are poorly understood. Here we describe a molecular mechanism that can target conventional endosomes for autophagic degradation. We show that the human transmembrane protein TMEM59 contains a minimal 19-amino-acid peptide in its intracellular domain that promotes LC3 labelling and lysosomal targeting of its own endosomal compartment. Interestingly, this peptide defines a novel protein motif that mediates interaction with the WD-repeat domain of ATG16L1, thus providing a mechanistic basis for the activity. The motif is represented with the same ATG16L1-binding ability in other molecules, suggesting a more general relevance. We propose that this motif may play an important role in targeting specific membranous compartments for autophagic degradation, and therefore it may facilitate the search for adaptor proteins that promote selective autophagy by engaging ATG16L1. Endogenous TMEM59 interacts with ATG16L1 and mediates autophagy in response to Staphylococcus aureus infection.This work was funded by grants from the Ministerio de Ciencia e Innovación of the Spanish Government (Refs SAF2008‐00350 and SAF2011‐23714), Fundación Solórzano, Junta de Castilla y León (Consejería de Educación, Ref. CSI001A10‐2, and Consejería de Sanidad) and Consejo Superior de Investigaciones Científicas (CSIC; Ref. 200720I026). Additional funding comes from the FEDER programme of the European Union. EB is a graduate student funded by a predoctoral fellowship from the FPU programme (Ministerio de Educación, MEC, Spanish Government). ML is funded by JAE‐Doc and Juan de la Cierva postdoctoral contracts (MEC and Social European Fund of the European Union, 2007–2013). AF is funded by a long‐term EMBO postdoctoral fellowship and a Juan de la Cierva contract. KP is a graduate student funded by an FPI fellowship (MEC).Peer Reviewe

πΞ\pi\Xi phase shifts and CP Violation in Ω→πΞ{\Omega\to\pi\Xi} Decay

In the study of CP violation signals in {\O}\to\pi\Xi nonleptonic decays, the strong $J$=3/2 $P$ and $D$ phase shifts for the $\pi\Xi$ final-state interactions are needed. These phases are calculated using an effective Lagrangian model, including $\Xi$, $\Xi^*$(1530), $\rho$ and the $\sigma$-term, in the intermediate states. The $\sigma$-term is calculated in terms of the scalar form factor of the baryon.Comment: 6 pages, 2 figure

Percutaneous ethanol injection for treatment of solid, cystic and autonomous thyroid nodules

Percutaneous ethanol injection (PEI) guided by ultrasound has been used for the treatment of cystic, solid and autonomous thyroid nodules. We present our experience in the treatment of 50 patients with thyroid nodules: 26 solid, 17 cystic and 7 autonomous (AN). Patients were evaluated 1 week, 1, 3, and 6 months and 1 year after PEI. After one year, solid nodules showed a mean 74% volume reduction, and cysts a volume reduction of 92%, with no recurrences. After one year, 5 patients with AN reached clinical and laboratory euthyroidism; the other 2 also became euthyroid, but with subnormal TSH. Recurrence of thyrotoxicosis was not observed and mean nodular reduction was 66%. The procedure was well tolerated by all patients. The results confirm that PEI is a good therapeutic alternative for reduction of solid and cystic thyroid nodules and for the treatment of autonomous nodules.A injeção percutânea de etanol (IPE) guiada por ultra-som tem sido utilizada para o tratamento de nódulos tiroidianos autônomos, sólidos e císticos. Apresentamos nossa experiência em 50 pacientes tratados, sendo 26 portadores de nódulos sólidos, 17 de nódulos císticos e 7 de nódulos autônomos (NA). Avaliamos os pacientes 1 semana, 1 mês, 3 meses, 6 meses e 1 ano após a IPE. Após 1 ano, os nódulos sólidos reduziram a 74% do volume inicial, os císticos diminuíram 92% sem apresentar recidivas. Um ano após o tratamento dos nódulos autônomos, 5 pacientes estavam em eutiroidismo clínico e laboratorial e 2 em eutiroidismo mas com TSH subnormal. Não houve recorrência da tirotoxicose e a redução nodular foi de 66%. O procedimento foi bem tolerado por todos. Os resultados confirmam que a IPE é uma boa alternativa terapêutica para redução dos nódulos tiroidianos císticos e sólidos e no tratamento dos nódulos autônomos.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de MedicinaUNIFESP, EPM, Depto. de MedicinaSciEL