Daily estimates of the tropospheric aerosol optical thickness over land surface from MSG geostationary observations

The paper presents an innovative method to derive aerosol optical thickness (AOT) on a continental scale, using MSG observation. The approach consists in taking into account the high temporal resolution of the observing system, in order to discriminate between surface and aerosol effects. A suitably extended semi-empirical BRDF model is applied, combined with a recursive scheme. The method is not instrument-specific (can be adapted to instruments onboard polar satellites) and was tested with MSG/SEVIRI data over mid-latitude and African regions. The aerosol optical thickness estimates are compared to AERONET ground measurements and to the corresponding MODIS product over land. The method appears very promising for tracking anthropogenic emissions in the troposphere and also for estimating dust events over bright surfaces. The high spatial and temporal resolution of the estimate is appropriate to investigate the dependence of AOT on the density of urbanization and potentially on motor vehicle traffic. Finally, this study suggests that this approach is appropriate for multi-sensor data fusion, for the simultaneous retrieval of surface albedo and aerosol optical thickness, and to generate these products in near-real time with a very high generation frequency

Aerosols attenuating the solar radiation collected by solar tower plants: the horizontal pathway at surface level [Póster]

Póster elaborado para el Solar Paces 2015 celebrado del 12 al 16 de octubre de 2015 en Cape Town (Sudáfrica

Aerosols attenuating the solar radiation collected by solar tower plants: the horizontal pathway at surface level

Aerosols attenuate the solar radiation collected by solar tower plants (STP), along two pathways: 1) the atmospheric column pathway, between the top of the atmosphere and the heliostats, resulting in Direct Normal Irradiance (DNI) changes; 2) the grazing pathway close to surface level, between the heliostats and the optical receiver

Solar energy attenuated in a Solar Thermal Energy plant, due to aerosol extinction between the heliostats and the optical receiver

Presentación realizada en: 15th EMS Annual Meeting and 12th European Conference on Applications of Meteorology (ECAM) celebrado del 7 al 11 de septiembre de 2015 en Sofía, Bulgaria

Fundo soberano de riqueza do Estado do Rio de Janeiro como instrumento para alavancar o desenvolvimento econômico

Analisar como a dependência dos royalties do petróleo e a limitada pauta de exportações afetam a economia do Estado do Rio de Janeiro. Este é ponto de partida para o entendimento da importância de um Fundo Soberano de Riqueza para a elaboração de uma estratégia de desenvolvimento de longo prazo em um estado que vive um cenário de grandes desafios e é um dos epicentros da desindustrialização nacional. Além disso, mas não menos importante, o FSR poderia ser utilizado como instrumento anticíclico de política para atenuar os efeitos negativos causados pela queda na arrecadação em momentos como observado em período recente, fortemente influenciado pela variação da cotação do petróleo, que culminou com a adesão ao Regime de Recuperação Fiscal em 2017. A realização de investimentos de longo prazo com o objetivo de diversificar a estrutura econômica para que haja maior encadeamento produtivo, sem descuidar dos aspectos sociais, parece ser o caminho a ser trilhado

Biodegradable Pickering emulsions of Lipiodol for liver trans-arterial chemo-embolization

International audienceWater-in-oil (W/O) Lipiodol emulsions remain the preferable choice for local delivery of chemotherapy in the treatment of hepatocellular carcinoma. However, their low stability severely hampers their efficiency. Here, remarkably stable W/O Lipiodol emulsion stabilized by biodegradable particles was developed thanks to Pickering technology. The addition of poly(lactide-co-glycolide) nanoparticles (NPs) into the aqueous-phase of the formulation led to W/O Pickering emulsion by a simple emulsification process through two connected syringes. Influence of nanoparticles concentration and water/oil ratio on emulsion stability and droplet size were studied. All formulated Pickering emulsions were W/O type, stable for at least one month and water droplets size could be tuned by controlling nanoparticle concentration from 24 mm at 25 mg/mL to 69 mm at 5 mg/mL. The potential of these emulsions to efficiently encapsulate chemotherapy was studied through the internalization of doxorubicin (DOX) into the aqueous phase with a water/oil ratio of 1/3 as recommended by the medical community. Loaded-doxorubicin was released from conventional emulsion within a few hours whereas doxorubicin from stable Pickering emulsion took up to 10 days to be completely released. In addition, in vitro cell viability evaluations performed on the components of the emulsion and the Pickering emulsion have shown no significant toxicity up to relatively high concentrations of NPs (3 mg/mL) on two different cell lines: HUVEC and HepG2. Statement of Significance We present an original experimental research in the field of nanotechnology for biomedical applications. In particular, we have formulated, thanks to Pickering technology, a new therapeutic emulsion stabilized with biodegradable PLGA nanoparticles. As far as we know, this is the first therapeutic Pickering emulsion reported in the literature for hepatocellular carcinoma. Such a new emulsion allows to easily prepare a predictable and stable lipiodolized emulsion having all the required characteristics for optimum tumor uptake. As demonstrated throughout our manuscript, emulsions stabilized with these nanoparticles have the advantage of being biodegradable, biocompatible and less toxic compared to usual emulsions stabilized with synthetic surfactants. These findings demonstrate the plausibility of the use of Pickering emulsions for chemoembolization as a therapeutic agent in extended release formulations

Four quasars above redshift 6 discovered by the Canada-France High-z Quasar Survey

The Canada-France High-z Quasar Survey (CFHQS) is an optical survey designed to locate quasars during the epoch of reionization. In this paper we present the discovery of the first four CFHQS quasars at redshift greater than 6, including the most distant known quasar, CFHQS J2329-0301 at z=6.43. We describe the observational method used to identify the quasars and present optical, infrared, and millimeter photometry and optical and near-infrared spectroscopy. We investigate the dust properties of these quasars finding an unusual dust extinction curve for one quasar and a high far-infrared luminosity due to dust emission for another. The mean millimeter continuum flux for CFHQS quasars is substantially lower than that for SDSS quasars at the same redshift, likely due to a correlation with quasar UV luminosity. For two quasars with sufficiently high signal-to-noise optical spectra, we use the spectra to investigate the ionization state of hydrogen at z>5. For CFHQS J1509-1749 at z=6.12, we find significant evolution (beyond a simple extrapolation of lower redshift data) in the Gunn-Peterson optical depth at z>5.4. The line-of-sight to this quasar has one of the highest known optical depths at z~5.8. An analysis of the sizes of the highly-ionized near-zones in the spectra of two quasars at z=6.12 and z=6.43 suggest the IGM surrounding these quasars was substantially ionized before these quasars turned on. Together, these observations point towards an extended reionization process, but we caution that cosmic variance is still a major limitation in z>6 quasar observations.Comment: 15 pages, 9 figures, AJ, in press, minor changes to previous versio

Playmancer project: a serious videogame as an additional therapy tool for eating and impulse control disorders

Reviews and few non-controlled studies showed the effectiveness of several specific designed computer video-games as an additional form of treatment in several areas. However, there is a lack in the literature of specially designed serious-games for treating mental disorders. Playmancer (ICT European initiative) aims to develop and assess a serious videogame that may help to treat underlying processes (e.g. lack of self-control strategies) in Eating and Impulse control disorders. Preliminary data will be shown