Demonstration of the Formation of the Caffeine-Dichloromethane-water Emulsion using Quantum Chemistry

Researchers have been concerned with the subsequent study of caffeine extraction. The objective of this article was to demonstrate how the caffeine-dichloromethane-water emulsion is formed. We use the theory of the electron transfer coefficient (ETC) as the cornerstone of our research. All the simulations of the interactions of the substances involved were calculated with the hyperchem simulator. The emulsion is formed because the ETC = 36,196 of the caffeine-CH2Cl2 interaction is the lowest of the cross-band interactions of the mixture. It will expect massive amounts of caffeine emulsified with CH2Cl2 and water. In conclusion, the gravitational well and the quantum well of caffeine coincide in being the lowest of all the wells calculated. It means that both CH2Cl2 and H2O will not destroy caffeine. That is, caffeine will be kept as a pure substance even after extraction with these two solvents. Although CH2Cl2 extracts more caffeine, due to its low ETC, the product for human consumption can be contaminated

Acerca de las características físicas de las granizadas en Mendoza

Se analiza la conducta de las precipitaciones registradas en el transcurso de tres temporadas (1976-77 a 1978-79) en la región norte de la provincia de Mendoza a través del empleo de las variables diámetro real del granizo caído, energía cinética total del impacto, y cantidad de precipitación acumulada. Se determinan frecuencias horarias de ocurrencia de granizadas para toda la zona y por longitud geográfica dentro de la misma y la relación entre los focos de granizo y de precipitación líquida, graficándose el análisis de los datos de algunas tormentas. El material analizado aporta elementos a la climatología del granizo, sin intervención artificial sobre las nubes que lo producen.The behaviour of rainfall and hailfall in northen Mendoza is studied by means of the variables diameter of hailstones, impact energy and total amount of rainfall. Time frequency distributions of hall fall are determined both for the whole area under study and for bands of different longitude inside the area. Relationships between maxima of solid and liquid precipitation are also studied and the graphic analysis of data for several storms is shown. The data analyzed give an approach to the knowledge of climatology of hail before experiments of weather modification.Asociación Argentina de Geofísicos y Geodesta

Clayey materials for traditional bricks production in North-Eastern Italy through a combined compositional study: From firing dynamics to provenance

The compositional study of two main types of clayey materials outcropping nearby Padua (Veneto region, north-eastern Italy) and bricks used in historical constructions of the city is here addressed. Mineralogically, the clayey materials are illitic-chloritc clays, both non-carbonatic and carbonatic/highly-carbonatic clays, that chemically correspond to clays with important contents of silica and/or iron and of calcium and/or magnesium, respectively. Two main type of historic bricks were produced: i) one using mixtures of illitic/illitic-chloritic clays with abundant quartz and of carbonatic clays and firing temperatures between 950 and 1000 °C, and ii) a second one made out of illitic-chloritic clays non-carbonatic and fired around 850–900 °C. The comparative analysis between the mineralogical changes occurred in the clayey materials with increasing temperatures and the mineral assemblages detected in the studied bricks have provided evidences about the mixture of raw clays, that could be in turn compositionally similar to those analysed. The development of aluminium and magnesium-calcium silicates and/or magnesium silicates during the firing was fostered by mixing such base clays, giving rise to very durable and highly calcareous bricks. Whereas titanium and the trace elements zircon, vanadium, chromium and zinc may entail markers of provenance of illitic-chloritic clays quarried in the area, the strontium may represent a geochemical fingerprint for constraining supply areas of carbonatic clays. The compositional analysis carried out through the combined use of X-Ray Powder Diffraction (XRPD) and X-Ray Fluorescence Spectrometry (XRF) has provided data regarding to the composition and provenance of the starting clays as well as procedures and firing dynamics adopted for the manufacturing of the traditional bricks in the city of Padua from Roman Times to Renaissance.European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Individual Fellowship (grant agreement No 836122)Research Group of the Junta de Andalucía, Spain (RNM179

The Disk Substructures at High Angular Resolution Project (DSHARP). IV. Characterizing Substructures and Interactions in Disks around Multiple Star Systems

To characterize the substructures induced in protoplanetary disks by the interaction between stars in multiple systems, we study the 1.25 mm continuum and the 12CO(J = 2–1) spectral line emission of the triple systems HT Lup and AS 205, at scales of ≈5 au, as part of the Disk Substructures at High Angular Resolution Project (DSHARP). In the continuum emission, we find two symmetric spiral arms in the disk around AS 205 N, with a pitch angle of 14°, while the southern component AS 205 S, itself a spectroscopic binary, is surrounded by a compact inner disk and a bright ring at a radius of 34 au. The 12CO line exhibits clear signatures of tidal interactions, with spiral arms, extended arc-like emission, and high velocity gas, possible evidence of a recent close encounter between the disks in the AS 205 system, as these features are predicted by hydrodynamic simulations of flyby encounters. In the HT Lup system, we detect continuum emission from all three components. The primary disk, HT Lup A, also shows a two-armed symmetric spiral structure with a pitch angle of 4°, while HT Lup B and C, located at 25 and 434 au in projected separation from HT Lup A, are barely resolved with ~5 and ~10 au in diameter, respectively. The gas kinematics for the closest pair indicates a different sense of rotation for each disk, which could be explained by either a counter rotation of the two disks in different, close to parallel, planes, or by a projection effect of these disks with a close to 90° misalignment between them

Paving the way for adequate myelination: The contribution of galectin-3, transferrin and iron

AbstractConsidering the worldwide incidence of well characterized demyelinating disorders such as Multiple Sclerosis (MS) and the increasing number of pathologies recently found to involve hypomyelinating factors such as micronutrient deficits, elucidating the molecular basis of central nervous system (CNS) demyelination, remyelination and hypomyelination becomes essential to the development of future neuroregenerative therapies. In this context, this review discusses novel findings on the contribution of galectin-3 (Gal-3), transferrin (Tf) and iron to the processes of myelination and remyelination and their potentially positive regulation of oligodendroglial precursor cell (OPC) differentiation. Studies were conducted in cuprizone (CPZ)-induced demyelination and iron deficiency (ID)-induced hypomyelination, and the participation of glial and neural stem cells (NSC) in the remyelination process was evaluated by means of both in vivo and in vitro assays on primary cell cultures

The Disk Substructures at High Angular Resolution Project (DSHARP). VI. Dust Trapping in Thin-ringed Protoplanetary Disks

A large fraction of the protoplanetary disks observed with ALMA display multiple well-defined and nearly perfectly circular rings in the continuum, in many cases with substantial peak-to-valley contrast. The DSHARP campaign shows that several of these rings are very narrow in radial extent. In this Letter we test the hypothesis that these dust rings are caused by dust trapping in radial pressure bumps, and if confirmed, put constraints on the physics of the dust trapping mechanism. We model this process analytically in 1D, assuming axisymmetry. By comparing this model to the data, we find that all rings are consistent with dust trapping. Based on a plausible model of the dust temperature we find that several rings are narrower than the pressure scale height, providing strong evidence for dust trapping. The rings have peak absorption optical depth in the range between 0.2 and 0.5. The dust masses stored in each of these rings is of the order of tens of Earth masses, though much ambiguity remains due to the uncertainty of the dust opacities. The dust rings are dense enough to potentially trigger the streaming instability, but our analysis cannot give proof of this mechanism actually operating. Our results show, however, that the combination of very low and very large grains can be excluded by the data for all the rings studied in this Letter

The Disk Substructures at High Angular Resolution Program (DSHARP). VIII. The Rich Ringed Substructures in the AS 209 Disk

The Disk Substructures at High Angular Resolution Program (DSHARP). VIII. The Rich Ringed Substructures in the AS 209 Dis

The Disk Substructures at High Angular Resolution Project (DSHARP). VII. The Planet–Disk Interactions Interpretation

The Disk Substructures at High Angular Resolution Project (DSHARP) provides a large sample of protoplanetary disks with substructures that could be induced by young forming planets. To explore the properties of planets that may be responsible for these substructures, we systematically carry out a grid of 2D hydrodynamical simulations, including both gas and dust components. We present the resulting gas structures, including the relationship between the planet mass, as well as (1) the gaseous gap depth/width and (2) the sub/super-Keplerian motion across the gap. We then compute dust continuum intensity maps at the frequency of the DSHARP observations. We provide the relationship between the planet mass, as well as (1) the depth/width of the gaps at millimeter intensity maps, (2) the gap edge ellipticity and asymmetry, and (3) the position of secondary gaps induced by the planet. With these relationships, we lay out the procedure to constrain the planet mass using gap properties, and study the potential planets in the DSHARP disks. We highlight the excellent agreement between observations and simulations for AS 209 and the detectability of the young solar system analog. Finally, under the assumption that the detected gaps are induced by young planets, we characterize the young planet population in the planet mass–semimajor axis diagram. We find that the occurrence rate for \u3e5 M J planets beyond 5–10 au is consistent with direct imaging constraints. Disk substructures allow us to probe a wide-orbit planet population (Neptune to Jupiter mass planets beyond 10 au) that is not accessible to other planet searching techniques

Effects and Risk Assessment of the Polycyclic Musk Compounds Galaxolide (R) and Tonalide (R) on Marine Microalgae, Invertebrates, and Fish

The current research investigated the potential environmental risk of the polycyclic musk compounds, Galaxolide (R) (HHCB) and Tonalide (R) (AHTN), in the marine environments. These substances are lipophilic, bioaccumulated, and potentially biomagnified in aquatic organisms. To understand the toxicity of HHCB and AHTN, acute toxicity tests were performed by exposing marine microalgae (Phaeodactylum tricornutum, Tretraselmis chuii, and Isochrysis galbana), crustaceans (Artemia franciscana), echinoderms (Paracentrotus lividus), bivalves (Mytilus galloprovincialis), fish (Sparus aurata), and a candidate freshwater microalga (Raphidocelis subcapitata) to environmentally relevant concentrations (0.005-5 mu g/L) following standardized protocols (US EPA, Environment Canada and OECD). P. tricornutum and I. galbana were sensitive to both substances and for P. tricornutum exposed to HHCB and AHTN, the IC10 values (the inhibition concentration at which 10% microalgae growth inhibition was observed) were 0.127 and 0.002 mu g/L, respectively, while IC10 values calculated for I. galbana were 5.22 mu g/L (a little higher than the highest concentration) and 0.328 mu g/L, for HHCB and AHTN, respectively. Significant (p < 0.01) concentration dependent responses were measured in P. lividus and M. galloprovincialis larvae developments, as well as S. aurata mortality tested with HHCB. The effect of HHCB on P. lividus larvae development was the most sensitive endpoint recorded, producing an EC50 value (the effect concentration at which 50% effect was observed) of 4.063 mu g/L. Considering the risk quotients both substances seem to represent high environmental risk to P. tricornutum and M. galloprovincialis in marine environments

Correlaciones referidas al recurso eólico en Río Cuarto

Se presenta en primer lugar la validación de fórmulas conocidas que permiten relacionar la velocidad del viento a distintas alturas, cercanas a la superficie. La validación se realiza mediante la estimación de un coeficiente de un modelo lineal por cuadrados mínimos. El objetivo es aprovechar mediciones de la velocidad del viento a 2m, obtenidas en algunas localidades del sur de la provincia de Córdoba para una primera estimación del recurso eólico aprovechable por aerogeneradores de baja potencia instalados en dicha localidades. En segundo lugar se establece, con igual objetivo, una correlación entre las velocidades obtenidas en la ubicación del aerogenerador del GEA y las de la estación sinóptica más cercana del SMN.First, the validation of known formulae that relate wind speed between 2 and 20 m above the surface is presented. This validation is accomplished by comparison with the results of least squares fitting of a linear model. The purpose is to evaluate the use of available data series of wind speed at 2m, for a rough estimation of wind resource in several sites in the South of the province of Córdoba, to be used by stand alone wind generators. Secondly, it is analyzed the correlation between wind speed data obtained in our station and the closest synoptic station of the National Meteorological Survey and it is concluded that a linear correlation cannot be found.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES