Potential-dependent competitive processes on platinum in acid solution in the presence of propargyl alcohol

The electroadsorption interactions between dilute propargyl alcohol and smooth platinum in 0.5 M H2SO4 at 25° C have been investigated at different potentials. When the platinum electrode is covered by H atoms the hydrogenation of propargyl alcohol takes place. Otherwise, when the platinum electrode is held at a potential located in the double-layer region, the electroadsorption of propargyl alcohol involves a disruptive electro-oxidation yielding strongly bound adsorbed residues. The latter can be electrodesorbed presumably as carbon dioxide and protons. This process occurs within the O-electroadsorption potential range. The complete residue electrodesorption requires several voltammetric cycles. Competition between the hydrogenation reaction and the disruptive electroadsorption process can be observed at potentials where the platinum surface is partially covered by H atoms.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Validity of Cognitive Assessment Tools for Older Adult Hispanics: A Systematic Review

A higher prevalence and incidence of dementia is found in Hispanic/Latino older adults. Therefore, valid instruments are necessary to assess cognitive functioning in this population group. Our aim was to review existing articles that have examined and reported on the validity of cognitive assessment tools in Hispanic/Latino population groups in the United States

INFOPràcticum: i després del grau, què?

Podeu consultar la Vuitena trobada de professorat de Ciències de la Salut completa a: http://hdl.handle.net/2445/66524L'INFOPràcticum és una jornada en que s'organitzen un conjunt d'activitats (xerrades, taula rodona, presentació de pòsters sobre les pràctiques realitzades, etc.), pensades per orientar a l'alumnat de 4t. curs sobre les sortides professionals, i les possibilitats que té de seguir-se formant a l'INEFC. És també el moment en que l'alumnat de 4t. de grau..

Higher order glass-transition singularities in colloidal systems with attractive interactions

The transition from a liquid to a glass in colloidal suspensions of particles interacting through a hard core plus an attractive square-well potential is studied within the mode-coupling-theory framework. When the width of the attractive potential is much shorter than the hard-core diameter, a reentrant behavior of the liquid-glass line, and a glass-glass-transition line are found in the temperature-density plane of the model. For small well-width values, the glass-glass-transition line terminates in a third order bifurcation point, i.e. in a A_3 (cusp) singularity. On increasing the square-well width, the glass-glass line disappears, giving rise to a fourth order A_4 (swallow-tail) singularity at a critical well width. Close to the A_3 and A_4 singularities the decay of the density correlators shows stretching of huge dynamical windows, in particular logarithmic time dependence.Comment: 19 pages, 12 figures, Phys. Rev. E, in prin

Motivational crowding effects in payments for ecosystem services: Exploring the role of instrumental and relational values

Nature is perceived and valued in many different ways. Often, the types of values that are the most important to people depend on how they cognitively frame desirable human–nature relations. For instance, the value of nature can be seen through a utilitarian lens, for example, as providing ecosystem services for humans. Alternatively, it can also be considered valuable for non-instrumental reasons, for example, for its sacred or spiritual significance. In this paper, we use a framed field experiment to test how people belonging to three distinct communities in Colombia (Indigenous, Afro-Colombian and Campesino) respond to different ways of framing payments for ecosystem services (PES) schemes, so as to assess potential motivational crowding effects of pro-social/intrinsic motivations for forest conservation. The experimental results indicate that crowding-in of intrinsic motivations for forest conservation occurred in participants from the Indigenous community when the PES scheme was framed in a way that highlighted the relational values of the forest. By contrast, motivational crowding-in took place for participants in the framed field experiment from the Campesino community when the PES scheme was introduced in a way that highlighted instrumental values instead. Participants from the Afro-Colombian community did not show the evidence of motivational crowding under either framing. Together, these results suggest that PES schemes that are framed in a way that harmonizes with locally salient human–nature relational models and associated values are more likely to cause motivational crowding-in, and thus encourage the higher rates of environmental conservation, even after payments are discontinued. A free Plain Language Summary can be found within the Supporting Information of this article. © 2021 The Authors. People and Nature published by John Wiley & Sons Ltd on behalf of British Ecological Society.We would like to acknowledge the Corporaci?n aut?noma regional del Valle del Cauca (CVC), especially Andr?s Carmona and Santiago Mesa, the leaders and community members of Rio Bravo, the Resguardo Nasa Kiwe Embera Cham? (La Delfina) and the Consejo Comunitario Alto y Medio Dagua, without whom this study would not have been possible. We would also like to thank Adriana Bernal and Juan Felipe Ortiz-Riomalo for their insightful comments on an earlier draft of this manuscript. Funding for this research was provided by the Alexander von Humboldt-Foundation in the framework of the Alexander von Humboldt-Professorship endowed by the German Federal Ministry of Education and Research. B.L. and U.P. are supported by the Spanish Government through Mar?a de Maeztu Excellence Accreditation 2018?2022 (Ref. MDM-2017-0714). We would like to acknowledge the Corporación autónoma regional del Valle del Cauca (CVC), especially Andrés Carmona and Santiago Mesa, the leaders and community members of Rio Bravo, the Resguardo Nasa Kiwe Embera Chamí (La Delfina) and the Consejo Comunitario Alto y Medio Dagua, without whom this study would not have been possible. We would also like to thank Adriana Bernal and Juan Felipe Ortiz‐Riomalo for their insightful comments on an earlier draft of this manuscript. Funding for this research was provided by the Alexander von Humboldt‐Foundation in the framework of the Alexander von Humboldt‐Professorship endowed by the German Federal Ministry of Education and Research. B.L. and U.P. are supported by the Spanish Government through María de Maeztu Excellence Accreditation 2018–2022 (Ref. MDM‐2017‐0714)

Factorizing the time evolution operator

There is a widespread belief in the quantum physical community, and in textbooks used to teach Quantum Mechanics, that it is a difficult task to apply the time evolution operator Exp{-itH/h} on an initial wave function. That is to say, because the hamiltonian operator generally is the sum of two operators, then it is a difficult task to apply the time evolution operator on an initial wave function f(x,0), for it implies to apply terms operators like (a+b)^n. A possible solution of this problem is to factorize the time evolution operator and then apply successively the individual exponential operator on the initial wave function. However, the exponential operator does not directly factorize, i. e. Exp{a+b} is not equal to Exp{a}Exp{b}. In this work we present a useful procedure for factorizing the time evolution operator when the argument of the exponential is a sum of two operators, which obey specific commutation relations. Then, we apply the exponential operator as an evolution operator for the case of elementary unidimensional potentials, like the particle subject to a constant force and the harmonic oscillator. Also, we argue about an apparent paradox concerning the time evolution operator and non-spreading wave packets addressed previously in the literature.Comment: 24 pages; added references; one figure change

Observational evidence for matter propagation in accretion flows

We study simultaneous X-ray and optical observations of three intermediate polars EX Hya, V1223 Sgr and TV Col with the aim to understand the propagation of matter in their accretion flows. We show that in all cases the power spectra of flux variability of binary systems in X-rays and in optical band are similar to each other and the majority of X-ray and optical fluxes are correlated with time lag <1 sec. These findings support the idea that optical emission of accretion disks, in these binary systems,largely originates as reprocessing of X-ray luminosity of their white dwarfs. In the best obtained dataset of EX Hya we see that the optical lightcurve unambiguously contains some component, which leads the X-ray emission by ~7 sec. We interpret this in the framework of the model of propagating fluctuations and thus deduce the time of travel of the matter from the innermost part of the truncated accretion disk to the white dwarf surface. This value agrees very well with the time expected for matter threaded onto the magnetosphere of the white dwarf to fall to its surface. The datasets of V1223 Sgr and TV Col in general confirm these findings,but have poorer quality.Comment: 7 pages, 6 figures. Accepted for publication in MNRA

Evolutionary analysis of genes coding for Cysteine-RIch Secretory Proteins (CRISPs) in mammals

Cysteine-RIch Secretory Proteins (CRISP) are expressed in the reproductive tract of mammalian males and are involved in fertilization and related processes. Due to their important role in sperm performance and sperm-egg interaction, these genes are likely to be exposed to strong selective pressures, including postcopulatory sexual selection and/or male-female coevolution. We here perform a comparative evolutionary analysis of Crisp genes in mammals. Currently, the nomenclature of CRISP genes is confusing, as a consequence of discrepancies between assignments of orthologs, particularly due to numbering of CRISP genes. This may generate problems when performing comparative evolutionary analyses of mammalian clades and species. To avoid such problems, we first carried out a study of possible orthologous relationships and putative origins of the known CRISP gene sequences. Furthermore, and with the aim to facilitate analyses, we here propose a different nomenclature for CRISP genes (EVAC1-4, "EVolutionarily-analyzed CRISP") to be used in an evolutionary context.Fil: Arévalo, Lena. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; España. Universitat Bonn; AlemaniaFil: Brukman, Nicolás Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Cuasnicu, Patricia Sara. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Roldan, Eduardo R. S.. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; Españ