In honour of the 70th birthday of Professor Luis A. Oro

EssayWhen Professor Luis Oro turns over the middle of June, he will be 70 years old, and he will be completing a cycle of almost half a century (48 years) dedicated to chemical research in the field of organometallics and homogeneous catalysis, and in general to the development of chemistry. In this aim, he has assumed different and complementary responsibilities, from leading innovative research projects, to the formation of professional scientists for academia or the chemical industry, from the direction of the Spanish Royal Society of Chemistry, to that of diverse editorial management consortia or even having taken the responsibility of guiding the overall Spanish scientific policy. It has been a long trek done with tons of enthusiasm, excellent companions and plenty of generosity. It is our pleasure and privilege to walk around the main steps of Professor Oro’s life; a life dedicated to investigate and to work to situate chemical research, and science in general, in the proper place it should be in our modern society.Peer Reviewe

El conocimiento de los electrones determina la interacción molecular

Página web divulgativa.Peer Reviewe

Bacterial computing: A form of natural computing and its applications

The capability to establish adaptive relationships with the environment is an essential characteristic of living cells. Both bacterial computing and bacterial intelligence are two general traits manifested along adaptive behaviors that respond to surrounding environmental conditions. These two traits have generated a variety of theoretical and applied approaches. Since the different systems of bacterial signaling and the different ways of genetic change are better known and more carefully explored, the whole adaptive possibilities of bacteria may be studied under new angles. For instance, there appear instances of molecular "learning" along the mechanisms of evolution. More in concrete, and looking specifically at the time dimension, the bacterial mechanisms of learning and evolution appear as two different and related mechanisms for adaptation to the environment; in somatic time the former and in evolutionary time the latter. In the present chapter it will be reviewed the possible application of both kinds of mechanisms to prokaryotic molecular computing schemes as well as to the solution of real world problems

Phase estimation with limited coherence

We investigate the ultimate precision limits for quantum phase estimation in terms of the coherence, $C$, of the probe. For pure states, we give the minimum estimation variance attainable, $V(C)$, and the optimal state, in the asymptotic limit when the probe system size, $n$, is large. We prove that pure states are optimal only if $C$ scales as $n$ with a sufficiently large proportionality factor, and that the rank of the optimal state increases with decreasing $C$, eventually becoming full-rank. We show that the variance exhibits a Heisenberg-like scaling, $V(C) \sim a_n/C^2$, where $a_n$ decreases to $\pi^2/3$ as $n$ increases, leading to a dimension-independent relation.Comment: 10 pages, 5 figure

Optical Absorption by Indirect Excitons in a Transition Metal Dichalcogenide Double Layer

We calculate the binding energy, transition energies, oscillator strength, and absorption coefficient of indirect excitons in transition metal dichalcogenide (TMDC) double layers separated by an integer number of hexagonal boron nitride (h-BN) monolayers. The absorption factor, a dimensionless quantity which gives the fraction of incoming photons absorbed by the indirect excitons in the double layer, is evaluated. The aforementioned optical quantities are obtained for transitions from the ground state to the first two excited states. All quantities are studied as a function of the interlayer separation, which may be experimentally controlled by varying the number of h-BN monolayers between the TMDC layers. Calculations are performed by using the exciton wave function and eigenenergies obtained for the Keldysh potential. For each material, we choose a combination of the exciton reduced mass and the dielectric screening length from the existing literature which give the largest and the smallest indirect exciton binding energy. These combinations of material parameters provide upper and lower bounds on all quantities presented. Our findings can be examined experimentally via two-photon spectroscopy.Comment: 13 pages, 3 figure

Pixel Predicament

If the art that affected you greatly in your youth was under the risk of fading away, wouldn\u27t you do anything to preserve it? Gamers are tired of seeing the art of video games be neglected by their copyright holders and are making efforts to find, catalogue, and preserve their artform in multiple ways.https://flahoz.com/2023/01/24/pixel-predicament

Intravascular myopericytoma in the heel: Case report and literature review

Intravascular myopericytoma (IVMP), regarded as a variant of myopericytoma, is a rare tumor. Very few cases have been described, none in the foot. The first case of IVMP located in the heel of the foot is described in this article. A literature review is reported of all cases of IVMP published in the English literature. A 48-year-old man possessed an IVMP on the heel of the right foot. The physical examination and histopathological and ultrasound studies are described. The literature review yielded 5 cases of IVMP, 2 of which were in the thigh and 1 each in the oral mucosa, the periorbital region, and the leg. The possibility that these lesions may be malignant suggests that the histopathological study of vascular tumors should include immunohistochemical tests

El proceso de ficcionalidad en la narrativa del siglo XV: la función autor/narrador y la ilusión referencial

El artículo trata sobre los orígenes de la forma narrativa y, en este contexto, el análisis del proceso de ficcionalización. A partir de las propuestas primitivas del género, resulta más accesible el estudio de las categorías de la ficción, especialmente el proceso creativo que, desde la enunciación, se desarrolla hacia la elaboración del universo poético. Como referencia para el estudio se citan las siguientes obras: "Arcipreste de Talavera", "Espill" de Jaume Roig, y las principales obras de Diego de San Pedro. The article deals with the origins of the narrative style and, in this context, the analysis of the process of making fiction. Starting from the early proposals of this genre, it is much more accessible to study the fiction categories, especially the creative process which, from the enunciation, is developed towards the production of the poetical universe. As a reference for the study, the following novels are quoted: "Arcipreste de Talavera", "Espill" by Jaume Roig, and "Cárcel de amor" by Diego de San Pedro

Las cláusulas de relativo con antecedente humano en español: la difusión de la forma "el + que" entre los siglos XIX y XX

Based on a corpus of ego-documents from the 19th and 20th centuries, the paper offers the result of a variationist analysis to set the factors affecting the selection of forms article + que in relative clauses headed by preposition a with a human antecedent. The data show that, despite the remarkable vitality that still enjoys the traditional form in this context (the pronoun quien), several factors begin to favor the diffusion of the innovative variant in that seminal period. As usual in early stages of language change, the explanatory hierarchy begins with structural factors, among which are selected as significant those related with the antecedent (the distance between antecedent and pronoun, indeterminacy or definite determiner, semantic nature) and with the type of relative clause (non-defining). From the sociolectal point of view, the data show that there has been a change from below, especially in the 20th century.A partir de un corpus de textos cercanos a la inmediatez comunicativa de los siglos XIX y XX, se ofrecen los resultados de un análisis variacionista para delimitar los factores que condicionan la selección de las formas del artículo + que en relativas oblicuas encabezadas por la preposición a con antecedente humano. Los datos del estudio demuestran que, pese a la vitalidad de la que goza todavía la variante tradicional en este contexto (el pronombre quien), diversos factores comienzan a favorecer la difusión de la variante innovadora. Como es habitual en las fases iniciales del cambio lingüístico, la primacía explicativa corresponde a los factores estructurales, entre los que destacan los relacionados con el antecedente (no adyacencia, carácter indefinido o indeterminado, categoría semántica) y con el tipo de relativas (explicativas). Desde el punto de vista sociolectal, los datos obtenidos, sobre todo en el siglo XX, reflejan que se trata de un cambio desde abajo

Synthesis and catalytic activity of well-defined Co(i) complexes based on NHC–phosphane pincer ligands

A new methodology for the preparation of Co(I)–NHC (NHC = N-heterocyclic carbene) complexes, namely, [Co(PCNHCP)(CO)2][Co(CO)4] (1) and [Co(PCNHCP)(CO)2]BF4 (2), has been developed (PCNHCP = 1,3-bis(2-(diphenylphosphanyl)ethyl)-imidazol-2-ylidene). Both complexes can be straightforwardly prepared by direct reaction of their parent imidazolium salts with the Co(0) complex Co2(CO)8. Complex 1 efficiently catalyses the reductive amination of furfural and levulinic acid employing silanes as reducing agents under mild conditions. Furfural has been converted into a variety of secondary and tertiary amines employing dimethyl carbonate as the solvent, while levulinic acid has been converted into pyrrolidines under solventless conditions. Dehydrocoupling of the silane to give polysilanes has been observed to occur as a side reaction of the hydrosilylation process