Pisolitos ferruginosos en el Mioceno inferior-medio de Mallorca

El registro sedimentario Burdigaliense-Langhiense de Mallorca refleja el relleno de pequeños surcos de antepaís que se generaron por subsidencia flexural frente al orógeno bético. Este registro sinorogénico incluye una unidad inferior que caracteriza la sedimentación en una plataforma marina somera (Fm. Sant Elm) y otra superior turbidítica (Fm. Banyalbufar). En el límite entre ambas unidades se ha reconocido, en la zona central de la isla, la existencia de un nivel de pisolitos ferruginosos de menos de 20 cm de potencia. Los pisolitos llegan a superar los 6 mm de diámetro, son esféricos y están constituidos casi exclusivamente por delgadas envueltas concéntricas de goethita, aunque en los pisolitos de mayor tamaño alguna envuelta es de calcita. La posición estratigráfica del nivel de pinolitos coincide, aproximadamente, con el límite entre las dos unidades anteriormente citadas, localizándose inmediatamente antes del inicio de la sedimentación turbidítica, y se correspondería con el máximo transgresivo en la cuenca marina. Tanto el vulcanismo Burdigaliense que ha sido reconocido en la zona como la removilización de suelos lateríticos en relación con la transgresión marina pudieron haber actuado como fuentes suministradoras del hierro.The syn-orogenic Early-Middle Miocene of Mallorca constitutes a sequence which records the deepening and infill of small fore-deeps related to flexural subsidence caused by the Betic orogene thrusting. In the syn-orogenic Miocene of the central part of the island, a pisolitic iron bed less than 20 cm thick is first described in order to their stratigraphic, environmental and palaeogeographic significance. The pisolites are highly sphaerical and range from less than 0.25 to more than 6 mm in size. They are formed by concentric thin laminae (< 100 m) of goethite. The largest-sized pisolites also contain calcite laminae. The pisolitic bed is approximately located in the boundary between the shallow marine platform and the deeper turbidite deposits, recording the basin deepening and the maximum marine transgression. Both, the Burdigalian volcanism described in the zone as well as the removilization of continental lateritic soils by marine transgression are invoked as the probable iron sources

Boundary effects in finite size plasmonic crystals: Focusing and routing of plasmonic beams for optical communications

Plasmonic crystals, which consist of periodic arrangements of surface features at a metal-dielectric interface, allow the manipulation of optical information in the form of surface plasmon polaritons. Here we investigate the excitation and propagation of plasmonic beams in and around finite size plasmonic crystals at telecom wavelengths, highlighting the effects of the crystal boundary shape and illumination conditions. Significant differences in broad plasmonic beam generation by crystals of different shapes are demonstrated, while for narrow beams, the propagation onto the smooth metal film is less sensitive to the crystal boundary shape. We show that by controlling the boundary shape, the size and the excitation beam parameters, directional control of propagating plasmonic modes and associated beam parameters such as angular beam splitting, focusing power and beam width can be efficiently achieved. This provides a promising route for robust and alignment-independent integration of plasmonic crystals with optical communication components

Weighted norm inequalities for polynomial expansions associated to some measures with mass points

Fourier series in orthogonal polynomials with respect to a measure $\nu$ on $[-1,1]$ are studied when $\nu$ is a linear combination of a generalized Jacobi weight and finitely many Dirac deltas in $[-1,1]$. We prove some weighted norm inequalities for the partial sum operators $S_n$, their maximal operator $S^*$ and the commutator $[M_b, S_n]$, where $M_b$ denotes the operator of pointwise multiplication by b \in \BMO. We also prove some norm inequalities for $S_n$ when $\nu$ is a sum of a Laguerre weight on $\R^+$ and a positive mass on $0$

Light-front wave functions of vector mesons in an algebraic model

Inspired by the recent development of an algebraic model which provides an adequate and unified description of the internal structure of the lowest-lying pseudoscalar mesons, belonging both to the light quarks sector and to the one of heavy quarks, we perform its first extension to the vector-meson case. The algebraic model describes the meson’s structure in terms of the spectral density function that appears in a Nakanishi integral representation of the covariant quark-antiquark bound-state amplitude, i.e., the Bethe- Salpeter amplitude. We compute the leading-twist light-front wave functions of the ρð770Þ, ϕð1020Þ, J=ψ, and ϒð1SÞ mesons through their connection with the parton distribution amplitudes. Among the results we present, the following are of particular interest: (i) transverse light-front wave functions can be obtained algebraically from the corresponding parton distribution amplitudes, whereas that is not the case for longitudinal light-front wave functions, which requires an intermediate step where a spectral density function must be derived from the particular parton distribution amplitude; (ii) the derived spectral density functions show marked differences between light and heavy vector mesons, the latter being narrower as compared to the former, and these are also nonpositive definite, although the integral over the entire curve is larger than zero as expected; and (iii) the longitudinal and transverse light-front wave functions of vector mesons with light quark content exhibit steep x and p2 ⊥ dependence, while those of the J=ψ and ϒð1SÞ mesons are characterized by narrow distributions in the x range but, comparatively, much more gradual falloffs with respect to the p2 ⊥ range depicted.B. Almeida Zamora acknowledges CONACyT (Grant No. CVU 935777) for the Phd fellowship. J. J. Cobos-Martínez acknowledges financial support from the University of Sonora under Grant No. USO315007861. A. Bashir acknowledges Coordinación de la Investigación Científica of the Universidad Michoacana de San Nicolás de Hidalgo Grant No. 4.10., the U.S. Department of Energy (DOE) under Contract No. DE-AC05-6OR23177, and the Fulbright-García Robles Scholarship. This work has also been partially funded by Ministerio Español de Ciencia e Innovación under Grant No. PID2019–107844 GB-C22 and Junta de Andalucía under Contracts No. Operativo FEDER Andalucía 2014-2020 UHU-1264517, No. P18- FR-5057, and also No. PAIDI FQM-370

Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico

Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along the monitoring period. No anthropogenic pollution from Volatile Organic Compounds (VOCs) was observed. An overview of the soil radon behaviour as a function of the volcanic activity in the period 1994-2002 is also discussed

Automatic mental processes, automatic actions and behaviours in game transfer phenomena: an empirical self-report study using online forum data

Previous studies have demonstrated that the playing of videogames can have both intended and unintended effects. The purpose of this study was to investigate the influence of videogames on players’ mental processes and behaviours in day-to-day settings. A total of 1,023 self-reports from 762 gamers collected from online videogame forums were classified, quantified, described and explained. The data include automatic thoughts, sensations and impulses, automatic mental replays of the game in real life, and voluntary/involuntary behaviours with videogame content. Many gamers reported that they had responded – at least sometimes – to real life stimuli as if they were still playing videogames. This included overreactions, avoidances, and involuntary movements of limbs. These experiences lasted relatively short periods of time but in a minority of players were recurrent. The gamers' experiences appeared to be enhanced by virtual embodiment, repetitive manipulation of game controls, and their gaming habits. However, similar phenomena may also occur when doing other non-gaming activities. The implications of these game transfer experiences are discussed

Caracterização das condições climáticas na Amazônia.

bitstream/item/220361/1/CPAF-AP-2020-cap-2-Caracterizacao-das-condicoes-climaticas.pd