Glory revealed in disk-integrated photometry of Venus

Context. Reflected light from a spatially unresolved planet yields unique insight into the overall optical properties of the planet cover. Glories are optical phenomena caused by light that is backscattered within spherical droplets following a narrow distribution of sizes; they are well known on Earth as localised features above liquid clouds. Aims. Here we report the first evidence for a glory in the disk-integrated photometry of Venus and, in turn, of any planet. Methods. We used previously published phase curves of the planet that were reproduced over the full range of phase angles with model predictions based on a realistic description of the Venus atmosphere. We assumed that the optical properties of the planet as a whole can be described by a uniform and stable cloud cover, an assumption that agrees well with observational evidence. Results. We specifically show that the measured phase curves mimic the scattering properties of the Venus upper-cloud micron-sized aerosols, also at the small phase angles at which the glory occurs, and that the glory contrast is consistent with what is expected after multiple scattering of photons. In the optical, the planet appears to be brighter at phase angles of 11-13 deg than at full illumination; it undergoes a maximum dimming of up to 10 percent at phases in between. Conclusions. Glories might potentially indicate spherical droplets and, thus, extant liquid clouds in the atmospheres of exoplanets. A prospective detection will require exquisite photometry at the small planet-star separations of the glory phase angles.Comment: In press. Astronomy & Astrophysics. Letter to the Editor; 201

Coupling of morphology to surface transport in ion-beam irradiated surfaces. I. Oblique incidence

We propose and study a continuum model for the dynamics of amorphizable surfaces undergoing ion-beam sputtering (IBS) at intermediate energies and oblique incidence. After considering the current limitations of more standard descriptions in which a single evolution equation is posed for the surface height, we overcome (some of) them by explicitly formulating the dynamics of the species that transport along the surface, and by coupling it to that of the surface height proper. In this we follow recent proposals inspired by ``hydrodynamic'' descriptions of pattern formation in aeolian sand dunes and ion-sputtered systems. From this enlarged model, and by exploiting the time-scale separation among various dynamical processes in the system, we derive a single height equation in which coefficients can be related to experimental parameters. This equation generalizes those obtained by previous continuum models and is able to account for many experimental features of pattern formation by IBS at oblique incidence, such as the evolution of the irradiation-induced amorphous layer, transverse ripple motion with non-uniform velocity, ripple coarsening, onset of kinetic roughening and other. Additionally, the dynamics of the full two-field model is compared with that of the effective interface equation.Comment: 23 pages, 14 figures. Movies of figures 6, 7, and 8 available at http://gisc.uc3m.es/~javier/Movies

Determinants of disaffiliation: an international study

Using a dataset of 15,000 subjects from 32 Western countries, the current study examines individuals who were raised in a certain religion and, at some stage of their lives, left it. Currently, they define their religious affiliation as ‘no religion’. A battery of explanatory variables (country-specific, personal attributes and marriage variables) was employed to test for determinants of this decision. It was found that the tendency of individuals to leave their religion—the most extreme symptom of secularization—is strongly correlated with their liberal beliefs and with parental and spousal religious characteristics. Moreover, country characteristics, as well as personal socio-demographic features seem to be much less relevant, except for the religious diversity of the country that has a positive effect on disaffiliation

Intergenerational transmission of ‘religious capital’. Evidence from Spain

This paper examines intergenerational transmission of ‘religious capital’ from parents to their offspring within an economic framework. The analytical tool is a ‘production function of religiosity’ where parental religious inputs serve as factors of production. The database used is based on a large-scale survey that was conducted in 1998 in Spain. In addition to information on the religious affiliation of the respondent and his parents, it has detailed data on two dimensions of the individual’s religious performance: church attendance and prayer. It also includes information on the mother’s and father’s church attendance when the respondent was a child, as well as the respondent’s participation in mass services at the age of 12. Socio-economic background data are also available. The core findings are: (i) parental religious inputs significantly affect individuals’ religiosity; (ii) interestingly, the route of intergenerational transmission is from mother to daughter and from father to son; and (iii) current mass participation of respondents is more affected by parental- than by own childhood mass attendance

Evaluation of susceptibility to powdery mildew (Erysiphe necator) in Vitis vinifera varieties

Susceptibility to grape powdery mildew (Erysiphe necator Schwein.) was studied in 159 Vitis vinifera foreign and native grape varieties grown in Spain. The relationship between morphological features of vines and their susceptibility to the disease was also studied. The infection was evaluated under natural conditions on leaves and bunches. A total of 35 cultivars were very susceptible to the disease (very low to low resistance on bunches), while another 83 showed low susceptibility (high to very high resistance on bunches). Results provide useful information for grape growers and breeders for the selection of varieties less susceptible to powdery mildew

Multilayer hazes over Saturn’s hexagon from Cassini ISS limb images

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First high-resolution multi-proxy palaeoenvironmental record of the Late Glacial to Early Holocene transition in the Ría de Arousa (Atlantic margin of NW Iberia)

A 322-cm-long sedimentary sequence obtained in the shallow marine basin of the Ría de Arousa—a submerged unglaciated river valley on the Atlantic margin of northwestern Iberia—was analysed using a multi-proxy approach to study how climatic and sea level changes affected the coastal ecosystems during the Last Glacial–Interglacial Transition. Past sedimentation, vegetation and marine productivities were inferred from palynological, radiocarbon, seismic and lithological data. A substantial reduction in the pollen and dinoflagellate cyst accumulation rates is observed at ∼12,700 to 11,700 cal a BP, suggesting lower marine and vegetation productivities likely as a response to the Younger Dryas cooling event. Overall, the regional vegetation changed from cold-tolerant open woodlands (Pinus sylvestris/P. nigra and Betula) dominating before ∼10,200 cal a BP to coastal wetlands and the regional spread of Quercus-dominated forests after ∼9800 cal a BP. Cluster analysis and principal component analysis allowed the identification of several small environmental oscillations, such as the 11.4 ka and 10.5 ka cooling events. After that, a conspicuous heath expansion was likely favoured by the palaeotopography, the increased precipitation and the relative sea level rise, which might have caused a profound change in the coastal configuration. Concurrently, both the dinoflagellate cyst and non-pollen palynomorph records reveal variations in the marine productivity and coastal hydrodynamics that also agree with a period of marked marine transgression, warming and increasing river flow. New sedimentary data highlight the high sensitivity of the ria's ecosystems to environmental oscillations and show a close temporal correspondence between terrestrial and marine responses to climate change

Overview of the JET results in support to ITER

The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H = 1 at βN ~ 1.8 and n/nGW ~ 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D–T campaign and 14 MeV neutron calibration strategy are reviewed.European Commission (EUROfusion 633053

Mathematical modelling of water absorption and evaporation in a pharmaceutical tablet during film coating

It is well understood that during the pharmaceutical aqueous film coating process the amount of liquid water that interacts with the porous tablet core can affect the quality of the final product. Therefore, understanding and simulating the mechanisms of water droplet spreading, absorption and evaporation is crucial for controlling the process and optimising the shelf-life of the tablets. The purpose of the work presented in this paper is to define and describe the spreading, absorption and evaporation phenomena after droplet impingement on a tablet. We divided the droplet behaviour into three phases of different dynamics and duration: the kinematic, capillary and evaporation phases. To model the kinematic phase, we combined and modified 1-D spreading models from the literature which solve the kinetic energy balance equation for the first milliseconds of spreading. For the capillary phase, we simplified and solved the continuity and Navier-Stokes equations using the lubrication approximation theory. Finally, for the evaporation phase, we adopted a modelling approach for the second drying stage of slurry droplets inside a spray dryer. During this stage, one can no longer describe the droplet as a liquid system containing solids, having to regard it as a wet particle with a dry crust and a wet core. In our work, we represented in a novel way the crust as the dry surface of the tablet and the wet core as the wetted area inside the porous matrix. We implemented the mathematical model presented in this work in gPROMS, employing the Modelbuilder platform. Our numerical results (droplet height and spreading, wetting, evaporation front profiles) are in good agreement with recent experimental data that we found in the literature