ExTrA: Exoplanets in Transit and their Atmospheres

The ExTrA facility, located at La Silla observatory, will consist of a near-infrared multi-object spectrograph fed by three 60-cm telescopes. ExTrA will add the spectroscopic resolution to the traditional differential photometry method. This shall enable the fine correction of color-dependent systematics that would otherwise hinder ground-based observations. With both this novel method and an infrared-enabled efficiency, ExTrA aims to find transiting telluric planets orbiting in the habitable zone of bright nearby M dwarfs. It shall have the versatility to do so by running its own independent survey and also by concurrently following-up on the space candidates unveiled by K2 and TESS. The exoplanets detected by ExTrA will be amenable to atmospheric characterisation with VLTs, JWST, and ELTs and could give our first peek into an exo-life laboratory.Comment: 15 pages, 11 figures, SPIE 201

The quantum state vector in phase space and Gabor's windowed Fourier transform

Representations of quantum state vectors by complex phase space amplitudes, complementing the description of the density operator by the Wigner function, have been defined by applying the Weyl-Wigner transform to dyadic operators, linear in the state vector and anti-linear in a fixed `window state vector'. Here aspects of this construction are explored, with emphasis on the connection with Gabor's `windowed Fourier transform'. The amplitudes that arise for simple quantum states from various choices of window are presented as illustrations. Generalized Bargmann representations of the state vector appear as special cases, associated with Gaussian windows. For every choice of window, amplitudes lie in a corresponding linear subspace of square-integrable functions on phase space. A generalized Born interpretation of amplitudes is described, with both the Wigner function and a generalized Husimi function appearing as quantities linear in an amplitude and anti-linear in its complex conjugate. Schr\"odinger's time-dependent and time-independent equations are represented on phase space amplitudes, and their solutions described in simple cases.Comment: 36 pages, 6 figures. Revised in light of referees' comments, and further references adde

Homogeneously derived transit timings for 17 exoplanets and reassessed TTV trends for WASP-12 and WASP-4

19 pages, 4 figures, 6 tables; revised manuscript submitted to MNRAS; online-only supplements are in the download archiveWe homogeneously analyse ∼3.2 × 10 5 photometric measurements for ∼1100 transit light curves belonging to 17 exoplanet hosts. The photometric data cover 16 years (2004–2019) and include amateur and professional observations. Old archival light curves were reprocessed using up-to-date exoplanetary parameters and empirically debiased limb-darkening models. We also derive self-consistent transit and radial-velocity fits for 13 targets. We confirm the nonlinear transit timing variation (TTV) trend in the WASP-12 data at a high significance, and with a consistent magnitude. However, Doppler data reveal hints of a radial acceleration of about −7.5 ± 2.2 m s −1 yr −1, indicating the presence of unseen distant companions, and suggesting that roughly 10 per cent of the observed TTV was induced via the light-travel (or Roemer) effect. For WASP-4, a similar TTV trend suspected after the recent TESS observations appears controversial and model dependent. It is not supported by our homogeneous TTV sample, including 10 ground-based EXPANSION light curves obtained in 2018 simultaneously with TESS. Even if the TTV trend itself does exist in WASP-4, its magnitude and tidal nature are uncertain. Doppler data cannot entirely rule out the Roemer effect induced by possible distant companions.Peer reviewe

Howard walnut trees can be brought into bearing without annual pruning

In traditionally managed Howard walnut orchards, trees are pruned annually during the orchard development phase, an expensive operation in terms of labor and prunings disposal costs. Our observations and some prior research by others had suggested that pruning may not be necessary in walnut. In a trial of pruned and unpruned hedgerow trees over 8 years, beginning a year after planting, we documented canopy growth, tree height, yield and nut quality characteristics and also the effects of fruit removal. Pruning altered canopy shape but did not lead to increases in canopy development, yield or nut quality. Although fruit removal stimulated more vegetative growth in both the pruned and unpruned treatments, fruit removal did not result in an increase in midday canopy photosynthetically active radiation interception or cumulative yield when fruit removal was stopped after year 4. After 8 years, there were no significant differences in tree height, nut quality or cumulative yield among any of the treatments, which suggests that not pruning young Howard orchards could provide a net benefit to growers

Ectodysplasin A in Biological Fluids and Diagnosis of Ectodermal Dysplasia

The tumor necrosis factor (TNF) family ligand ectodysplasin A (EDA) is produced as 2 full-length splice variants, EDA1 and EDA2, that bind to EDA receptor (EDAR) and X-linked EDA receptor (XEDAR/EDA2R), respectively. Inactivating mutations in Eda or Edar cause hypohidrotic ectodermal dysplasia (HED), a condition characterized by malformations of the teeth, hair and glands, with milder deficiencies affecting only the teeth. EDA acts early during the development of ectodermal appendages-as early as the embryonic placode stage-and plays a role in adult appendage function. In this study, the authors measured EDA in serum, saliva and dried blood spots. The authors detected 3- to 4-fold higher levels of circulating EDA in cord blood than in adult sera. A receptor binding-competent form of EDA1 was the main form of EDA but a minor fraction of EDA2 was also found in fetal bovine serum. Sera of EDA-deficient patients contained either background EDA levels or low levels of EDA that could not bind to recombinant EDAR. The serum of a patient with a V262F missense mutation in Eda, which caused a milder form of X-linked HED (XLHED), contained low levels of EDA capable of binding to EDAR. In 2 mildly affected carriers, intermediate levels of EDA were detected, whereas a severely affected carrier had no active EDA in the serum. Small amounts of EDA were also detectable in normal adult saliva. Finally, EDA could be measured in spots of wild-type adult or cord blood dried onto filter paper at levels significantly higher than that measured in EDA-deficient blood. Measurement of EDA levels combined with receptor-binding assays might be of relevance to aid in the diagnosis of total or partial EDA deficiencies

Measurement and modeling of carbon balance of the apple tree

Measurement and modeling of carbon balance of the apple tre