Divesting power

We study alternative market power mitigation measures in a model where a dominant producer faces a competitive fringe with the same cost structure. We characterise the asset divestment by the dominant firm which achieves the greatest reduction in prices. This divestment entails the sale of marginal assets whose cost range encompasses the post-divestment price. A divestment of this type can be several times more effective in reducing prices than divestments of baseload (or low-cost) assets. We also establish that financial contracts (modeled as Virtual Power Plant schemes) are at best equivalent to baseload divestments in terms of consumer welfare.Divestments; Virtual power plants; contracts; market power; electricity; antitrust remedies;

Foreclosing competition through access charges and price discrimination

This article analyzes competition between two asymmetric networks, an incumbent and a new entrant. Networks compete in non-linear tariffs and may charge different prices for on-net and off-net calls. Departing from cost-based access pricing allows the incumbent to foreclose the market in a profitable way. If the incumbent benefits from customer inertia, then it has an incentive to insist on the highest possible access markup even if access charges are reciprocal and even in the absence of actual switching costs. If instead the entrant benefits from customer activism, then foreclosure is profitable only when switching costs are large enough.Networks; benefits; costs; customer;

Examining Potential Teacher Bias Of Hispanic Males With Emotional Disturbances In Virtual Settings

The importance of looking at student and teacher interactions holistically is essential and results in reflective teaching practices; consequently, the reflective practice of teaching needs to incorporate all facets of the teacher, known and unknown. This study looks at the potential influence of hidden biases towards adolescent Hispanic males and students with Emotional Behavior Disorders by observing preservice teacher (PT) interactions with students within a simulated classroom environment. Factorial MANOVAs and Discriminant analyses revealed statistically significant interactions and relationships between participant level of bias and the identified student avatars. These exchanges were more prevalent with one student avatar by both experimental and control PTs; indicating that student characteristics and their differences are important factors that need to be considered when addressing issues related to bias

Mobile Termination and Consumer Expectations under the Receiver-Pays Regime

We analyze how termination charges affect retail prices when taking into account that receivers derive some utility from a call and when firms may charge consumers for receiving calls. A novel feature of our paper is that we consider passive self-ful filling expectations and do not allow for negative reception charges. We recon rm the finding of pro t neutrality when firms cannot use termination-based price discrimination and show that connectivity is prone to breakdown

Bioinspired design of triboceramics: Learning from the anisotropic microfracture response of dental enamel under sliding contact

[EN] In the quest for novel ceramics for tribological applications via bioinspired design, the differences in the fracture modes that arise upon scratching relevant locations of ceramic-like tooth enamel are investigated. It is found that fracture initiates from weak rod-sheath interfaces at relatively low loads, independent of the sliding direction. However, the geometry and propagation of the cracks depends on the orientation of the interfaces relative to the maximum tensile stress: scratching along the occlusal surface propagates approximately sinusoidal cracks, parallel to the sliding direction, while scratching along the cross-section produces straight cracks that propagate normal (scratch parallel to occlusal surface) or parallel (scratch perpendicular to occlusal surface) to the sliding direction. The formation of cracks is hindered in scratching near the enamel-dentine junction. Implications for the microstructural design of triboceramics (bulks and coatings) with improved durability are discussed.The authors wish to thank Dr Florencio Monje Gil for kindly providing tooth specimens from his clinic (CICOM, Centro de Implantologia Cirugia Oral y Maxilofacial, Badajoz, Spain). This study was supported by Junta de Extremadura, Spain, and FEDER/ERDF funds (grants IB16139 and GR18149), and the Spanish Ministry of Science and Innovation (grant PID2019-105377RB-I00). E. P.-C. gratefully acknowledges support from the Spanish Ministry of Economy and Competitiveness (MINECO) under grant FJCI-2015-27228.Sanchez-Gonzalez, E.; Rodriguez-Rojas, F.; Pinilla-Cienfuegos, E.; Borrero-Lopez, O.; Ortiz, AL.; Guiberteau, F. (2020). Bioinspired design of triboceramics: Learning from the anisotropic microfracture response of dental enamel under sliding contact. Ceramics International. 46(18):27983-27989. https://doi.org/10.1016/j.ceramint.2020.07.2922798327989461

Photovoltaic LiNbO3particles: Applications to Biomedicine/Biophotonics

Recently, a novel method to trap and pattern ensembles of nanoparticles has been proposed and tested. It relies on the photovoltaic (PV) properties of certain ferroelectric crystals such as LiNbO3 [1,2]. These crystals, when suitably doped, develop very high electric fields in response to illumination with light of suitable wavelength. The PV effect lies in the asymmetrical excitation of electrons giving rise to PV currents and associated space-charge fields (photorefractive effect). The field generated in the bulk of the sample propagates to the surrounding medium as evanescent fields. When dielectric or metal nanoparticles are deposited on the surface of the sample the evanescent fields give rise to either electrophoretic or dielectrophoretic forces, depending on the charge state of the particles, that induce the trapping and patterning effects [3,4]. The purpose of this work has been to explore the effects of such PV fields in the biology and biomedical areas. A first work was able to show the necrotic effects induced by such fields on He-La tumour cells grown on the surface of an illuminated iron-doped LiNbO3 crystal [5]. In principle, it is conceived that LiNbO3 nanoparticles may be advantageously used for such biomedical purposes considering the possibility of such nanoparticles being incorporated into the cells. Previous experiments using microparticles have been performed [5] with similar results to those achieved with the substrate. Therefore, the purpose of this work has been to fabricate and characterize the LiNbO3 nanoparticles and assess their necrotic effects when they are incorporated on a culture of tumour cells. Two different preparation methods have been used: 1) mechanical grinding from crystals, and 2) bottom-up sol-gel chemical synthesis from metal-ethoxide precursors. This later method leads to a more uniform size distribution of smaller particles (down to around 50 nm). Fig. 1(a) and 1(b) shows SEM images of the nanoparticles obtained with both method. An ad hoc software taking into account the physical properties of the crystal, particullarly donor and aceptor concentrations has been developped in order to estimate the electric field generated in noparticles. In a first stage simulations of the electric current of nanoparticles, in a conductive media, due to the PV effect have been carried out by MonteCarlo simulations using the Kutharev 1-centre transport model equations [6] . Special attention has been paid to the dependence on particle size and [Fe2+]/[Fe3+]. First results on cubic particles shows large dispersion for small sizes due to the random number of donors and its effective concentration (Fig 2). The necrotic (toxicity) effect of nanoparticles incorporated into a tumour cell culture subjected to 30 min. illumination with a blue LED is shown in Fig.3. For each type of nanoparticle the percent of cell survival in dark and illumination conditions has been plot as a function of the particle dilution factor. Fig. 1a corresponds to mechanical grinding particles whereas 1b and 1c refer to chemically synthesized particles with two oxidation states. The light effect is larger with mechanical grinding nanoparticles, but dark toxicity is also higher. For chemically synthesized nanoparticles dark toxicity is low but only in oxidized samples, where the PV effect is known to be larger, the light effect is appreciable. These preliminary results demonstrate that Fe:LiNbO· nanoparticles have a biological damaging effect on cells, although there are many points that should be clarified and much space for PV nanoparticles optimization. In particular, it appears necessary to determine the fraction of nanoparticles that become incorporated into the cells and the possible existence of threshold size effects. This work has been supported by MINECO under grant MAT2011-28379-C03

Atualização da informação geológica e estratigráfica das jazidas de dinossáurios de La Rioja. Paleodiversidade do Cretácico Inferior do Grupo Enciso em Peña Cárcena (Igea, Espanha)

ABSTRACT: The discovery of new vertebrate fossil sites with skeletal remains in the Enciso Group of Igea (La Rioja) is showing the relevance of the area to study the palaeobiodiversity of Early Cretaceous vertebrate faunas from the Iberian Peninsula. At Peña Cárcena hill two sedimentary environments have been inferred: a mixed siliciclastic-carbonate lacustrine environment that is dominant at the outcrops, overlaid by a splay delta in an avulsion-belt. The vertebrate remains are especially abundant in the mixed siliciclastic-carbonate lacustrine deposits with two partially articulated skeletons (a theropod and a large-sized dinosaur), teeth and a fragment of a left maxilla of baryonychines, a pterosaur tooth that differs from those of Prejanopterus, a Goniopholis tooth, chelonian shell fragments that might belong to Camerochelys, a fairly complete lepisosteiform, teeth and dorsal fin spines of hybodontiforms. At the delta deposits, vertebrate fossils are rather scarce, with a single lepisosteiform skeleton and indeterminate bone fragments.RESUMO: A descoberta de novas jazidas com restos osteológicos de vertebrados no Grupo Enciso em Igea (La Rioja) comprova a importância da região para o estudo da paleobiodiversidade das faunas de vertebrados do Cretácico Inferior da Península Ibérica. Na colina de Peña-Cárcena, tem-se inferido dois ambientes sedimentares: o predominante nos afloramentos corresponde a um ambiente lacustre, siliciclástico-carbonatado misto, que se encontra sobreposto por depósitos de transbordo deltaico em cinturão abandonado. Restos de vertebrados são abundantes nos depósitos lacustres, incluindo dois esqueletos parciais articulados (de um terópode e de outro dinossáurio de grande porte), dentes e um fragmento de maxila esquerda de barionicinos, um dente de pterossáurio distinto de Prejanopterus, um dente de Goniopholis, fragmentos da carapaça de quelónios que poderão pertencer a Camerochelys, um lepisosteiforme praticamente completo, dentes e espinhos de barbatanas de hybodontiformes. Fósseis de vertebrados são escassos nos depósitos deltaicos, com apenas um esqueleto de lepisosteiforme e fragmentos indeterminados.info:eu-repo/semantics/publishedVersio

Frustration Response in Humans

La frustración es un estado emocional que se desencadena ante acontecimientos que involucran la reducción o supresión inesperada de reforzadores apetitivos. En este artículo se presentan una serie de trabajos realizados con humanos en los cuales se omiten, devalúan o interrumpen refuerzos alimenticios, monetarios, sociales y juegos de entretenimientos. La mayoría de los resultados experimentales son análogos a los hallados con animales no humanos, aunque agregan información sobre reacciones específicamente humanas, tales como los informes verbales, las expresiones faciales y cómo se regula mediante los estilos atribucionales y la personalidad. Finalmente se discute si la frustración puede o no enmarcarse dentro de las emociones básicas.Frustration is an emotional state elicitated by the unexpected reduction or suppression of appetitive reinforcers. In this article studies of frustration with humans are presented, in which food, monetary, social reinforcers and entertainment games are either omitted, devaluated or interrupted. The majority of the experimental results are analogous to the results founded with non-human subjects, though they add information about human reactions such as verbal reports, facial expressions, and how these responses are regulated by the contribution of attribution styles and personality. Finally, the possibility of categorizing frustration as one of the basic emotions is also discussed.Fil: Kamenetzky, Giselle Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Cuenya, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Elgier, Angel Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Lopez Seal, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Fosacheca, Sandro Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Martin, L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Mustaca, Alba Elisabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentin

Simulations of micro-sphere/shell 2D silica photonic crystals for radiative cooling

Altres ajuts: the CERCA Program/Generalitat de Catalunya.L'article s'ha publicat sota la OSA Open Access Publishing Agreement https://www.osapublishing.org/submit/review/pdf/OSACopyTransferOAAgrmnt(2017-09-05).pdfPassive daytime radiative cooling has recently become an attractive approach to address the global energy demand associated with modern refrigeration technologies. One technique to increase the radiative cooling performance is to engineer the surface of a polar dielectric material to enhance its emittance atwavelengths in the atmospheric infrared transparency window (8-13 ìm) by outcoupling surface-phonon polaritons (SPhPs) into free-space. Here we present a theoretical investigation of new surface morphologies based upon self-assembled silica photonic crystals (PCs) using an in-house built rigorous coupled-wave analysis (RCWA) code. Simulations predict that silica micro-sphere PCs can reach up to 73 K below ambient temperature, when solar absorption and conductive/convective losses can be neglected. Micro-shell structures are studied to explore the direct outcoupling of the SPhP, resulting in near-unity emittance between 8 and 10 ìm. Additionally, the effect of material composition is explored by simulating soda-lime glass micro-shells, which, in turn, exhibit a temperature reduction of 61 K below ambient temperature. The RCWA code was compared to FTIR measurements of silica micro-spheres, self-assembled on microscope slides

Optoelectronic generation of bio-aqueous femto-droplets based on the bulk photovoltaic effect

"© 2020 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited"The generation and manipulation of small aqueous droplets is an important issue for nano- and biotechnology, particularly, when using microfluidic devices. The production of very small droplets has been frequently carried out by applying intense local electric fields to the fluid, which requires power supplies and metallic electrodes. This procedure complicates the device and reduces its versatility. In this work, we present a novel and flexible, to the best of our knowledge, electrodeless optoelectronic method for the production of tiny droplets of biologically friendly aqueous fluids. Our method takes advantage of the photoinduced electric fields generated by the bulk photovoltaic effect in iron-doped lithium niobate crystals. Two substrate configurations, presenting the polar ferroelectric axis either parallel or perpendicular to the active surface, have been successfully tested. In both crystal geometries, small droplets on the femtoliter scale have been obtained, although with a different spatial distributions correlated with the symmetry of the photovoltaic fields. The overall results demonstrate the effectiveness of the optoelectronic method to produce femtoliter droplets, both with pure water and with aqueous solutions containing biological materialMinisterio de Ciencia, Innovación y Universidades of Spain (MAT2017-83951-R); Marie Sklodowska-Curie Action COFUND (713366-InterTalentum