CNDOL is an a priori, approximate Fockian for molecular wave functions. In this study, we employ several modes of singly excited configuration interaction (CIS) to model molecular excitation properties by using four combinations of the one electron operator terms. Those options are compared to the experimental and theoretical data for a carefully selected set of molecules. The resulting excitons are represented by CIS wave functions that encompass all valence electrons in the system for each excited state energy. The Coulomb-exchange term associated to the calculated excitation energies is rationalized to evaluate theoretical exciton binding energies. This property is shown to be useful for discriminating the charge donation ability of molecular and supermolecular systems. Multielectronic 3D maps of exciton formal charges are showcased, demonstrating the applicability of these approximate wave functions for modeling properties of large molecules and clusters at nanoscales. This modeling proves useful in designing molecular photovoltaic devices. Our methodology holds potential applications in systematic evaluations of such systems and the development of fundamental artificial intelligence databases for predicting related properties.

Anthocyanins are natural pigments responsible for color in fruits and flowers. They are unstable to diverse ambient conditions like pH, light, or the presence of ions. Thus, in industry, several techniques are employed to protect and use anthocyanins. Likewise, ancient Mayas used clay and indigo extract to prepare a pigment known as Maya Blue, resistant to time and chemicals. For this reason, this work aims to characterize the hibiscus extract and sepiolite bio-hybrids created according to Maya methodology and observe the stability of anthocyanins, which are colorresponsible in flowers and fruits. Spectral analysis shows that anthocyanins and color were more stable than controls. Powder bio-hybrids show less color change under UV radiation and allochroic behavior in acid or alkaline atmospheres. At the same time, spectroscopy analyses and X-ray diffraction show no chemical interaction between sepiolite and hibiscus compounds. Our molecular dynamics with Reactive Force Fields (ReaxFF) studies reveal a similar behavior. Thus, our method protected the color of anthocyanins, in the temperature range from 15 to 35 degrees C. The interaction of hibiscus compounds with clay is due to van der Waals forces.

Margaritasite is a mineral compound discovered in the early 1980s in Chihuahua, Mexico. It is a natural cesium uranyl vanadate found only, so far, in the Margaritas mine of the Peña Blanca highlands. In this work, a thorough characterization of the aforementioned mineral is presented. The portfolio of the techniques employed includes high-resolution X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy, transmission electron microscopy in selected area electron diffraction (SAED) mode, and X-ray absorption spectroscopy (XAS). After extensive data analysis and modeling, new information on the mineral has been retrieved. Its phase composition is margaritasite–carnotite: a solid solution of cesium and potassium uranyl vanadate [(Cs,K)2(UO2)2(VO4)2·nH2O], and margaritasite, which is practically pure cesium uranyl vanadate [Cs2(UO2)2(VO4)2·nH2O]. The crystal structure of both components presents the space group P 1 21/c 1. Yet, each phase has similar, but appreciably different, lattice parameters. The mineral has a lamellar tabular and prismatic morphology. SAED patterns confirm the crystal structure of margaritasite. XAS spectra of Cs, V, and U confirm the elemental composition, oxidation states, and interatomic distances of this structure. These findings are consistent with the presence of cesium in this unique mineral from the paragenesis point of view.

The Open Databases Integration for Materials Design (OPTIMADE) application programming interface (API) empowers users with holistic access to a growing federation of databases, enhancing the accessibility and discoverability of materials and chemical data. Since the first release of the OPTIMADE specification (v1.0), the API has undergone significant development, leading to the upcoming v1.2 release, and has underpinned multiple scientific studies. In this work, we highlight the latest features of the API format, accompanying software tools, and provide an update on the implementation of OPTIMADE in contributing materials databases. We end by providing several use cases that demonstrate the utility of the OPTIMADE API in materials research that continue to drive its ongoing development.

Ferrimagnets are highly sought-after materials thanks to their strong perpendicular magnetic anisotropy (PMA) and low magnetization. For example, they are promising materials for current-induced magnetization switching applications. Ferrimagnetic D022-Mn3Ga integrates these properties with a low damping constant and a high Curie temperature. Here, we report a complete analysis of the magnetization and the effective PMA evolution with the thickness of the epitaxial D022-Mn3+xGa ultrathin films. The crystals were grown by magnetron sputtering following two methods: reactive deposition epitaxy and solid phase epitaxy. We found that the uniaxial PMAs and the thickness of the dead magnetic layers differ strongly upon the employed growth method, while saturation magnetizations remain unchanged. Structural defects at the interface due to lattice mismatch and growth method, explain our results. We expose objective estimations of the thermal stability factor Δ, based on the effective PMA in the ultrathin film context. Taking into account our results, D022-Mn3+xGa, in this form, can be employed as the free layer on magnetic tunnel junctions.

We report on the growth of Mn5Ge3 thin films on Ge(001) substrates following two methods: solid phase epitaxy (SPE) and reactive deposition epitaxy (RDE). We have varied the thickness of the films, in order to study the magnetization and anisotropy evolution. A strongly enhanced magnetization of 1580 kA m−1, compared to 1200 ± 150 kA m−1 for films grown on Ge(111), has been measured on ultrathin films of 5 nm grown by RDE. Thicker films exhibited magnetizations <750 kA m−1. The films grown by SPE also exhibit strong magnetization of 1490 kA m-1 and a drop of magnetization by increasing the film thickness. The effective magnetic anisotropy exhibits a more complex behavior: increases on the SPE films and decreases on the RDE films while increasing the thickness of the films. Magnetostatic and interfacial anisotropies were considered and calculated. The results are discussed in terms of the growth methods and microstructure of the films.

Naica's "Cueva de los Cristales" (Cave of the Crystals) has been compared to the most beautiful places of worship for the incredible display of columns that populate its vault. Said columns are giant gypsum crystals that have already been the subject of extensive studies. This paper contributes to these studies by focusing on the mineral aggregates found at the wall-selenite interface. A detailed chemical and structural characterization of representative samples has been performed using chemical, mineralogical, elemental, and phase analysis methods, with an emphasis on synchrotron micro-spectroscopic techniques. The following main phases were identified: calcite, silica, goethite, and several Pb-, Mn-, Cu-, and Zn-based aggregates. The role of the mineral aggregates, from their potential incorporation at the very beginning of the formation to the final steps of the crystals' growth, is investigated. Particular attention is paid to their shapes and composition. The data obtained on the morphology of the wallcrystal interface and related phase composition, together with classical nucleation formalisms based on the slightly supersaturated solution, suggest that the nanocrystalline monomers formed in solution undergo adsorption on the wall, which ultimately promotes mega crystal growth.

The magnetoresistive random access memory requires perpendicular magnetic tunnel junctions to simplify architecture, thus reducing the bit size and the energy consumption. The pinning of the fixed ferromagnetic (F) layer, in such structures, is achieved by the exchange bias effect at the interface with an antiferromagnetic (AF) thin film. Here, we report on the growth, by magnetron sputtering, of epitaxial AF-F systems with perpendicular magnetic anisotropy on MgO (001) substrates. The cubic L12-Mn3Ga thin film is AF and, by the creation of GaMn antisites, the cubic L12-Mn2.6Ga is F. First- Principles calculations, employing density functional theory, were performed to evaluate the effect of the gradual creation of Ga Mn antisites on the evolution of the colineal spin structure, describing magnetic disorder at the AF/F interface, which favor the exchange bias coupling. The exchange bias field HEB has been measured at 200 K in two configurations: F/AF/substrate and AF/F/substrate, being null on the former and of 10 mT on the second. In these systems, the role of the interface roughness has been considered to explain the HEB by the Malozemoff model.

BACKGROUND Andersen-Tawil Syndrome type 1 (ATS1) is a rare arrhythmogenic disorder, caused by loss-of-function mutations in the KCNJ2 gene. We present here the largest cohort of patients with ATS1 with outcome data reported. OBJECTIVES This study sought to define the risk of life-threatening arrhythmic events (LAE), identify predictors of such events, and define the efficacy of antiarrhythmic therapy in patients with ATS1. METHODS Clinical and genetic data from consecutive patients with ATS1 from 23 centers were entered in a database implemented at ICS Maugeri in Pavia, Italy, and pooled for analysis. RESULTS We enrolled 118 patients with ATS1 from 57 families (age 23 +/- 17 years at enrollment). Over a median follow-up of 6.2 years (interquartile range: 2.7 to 16.5 years), 17 patients experienced a first LAE, with a cumulative probability of 7.9% at 5 years. An increased risk of LAE was associated with a history of syncope (hazard ratio [HR]: 4.54; p = 0.02), with the documentation of sustained ventricular tachycardia (HR 9.34; p = 0.001) and with the administration of amiodarone (HR: 268; p < 0.001). The rate of LAE without therapy (1.24 per 100 person-years [py]) was not reduced by beta-blockers alone (1.37 per 100 py; p = 1.00), or in combination with Class Ic antiarrhythmic drugs (1.46 per 100 py, p = 1.00). CONCLUSIONS Our data demonstrate that the clinical course of patients with ATS1 is characterized by a high rate of LAE. A history of unexplained syncope or of documented sustained ventricular tachycardia is associated with a higher risk of LAE. Amiodarone is proarrhythmic and should be avoided in patients with ATS1. (C) 2020 Published by Elsevier on behalf of the American College of Cardiology Foundation.

Mycotoxins known as aflatoxins (AF) are produced as a secondary metabolite by some species of Aspergillus fungi. They are considered carcinogenic, hepatotoxic, teratogenic, and mutagenic. In this study, the molecular structure, chemical reactivity, and charge transfer values of AFB1, B2, G1, and G2 were analyzed using density functional theory. Different methodologies—B3LYP/6-311G(d,p) and M06-2X/6-311G(d,p)—were applied for geometrical calculations. Chemical reactivity parameters were used in the calculation of charge transfer values during the interaction between protein and ligand. The binding energy, the electrostatic interactions, and the amino acids of the active site were determined by molecular docking analysis between AF and cytochromes P450 (3A4 and 1A2), employing different PDB files (CYP3A4:1TQN, 2V0M, 4NY4 and 1W0E, and CYP1A2:2HI4). Molecular docking analysis indicated that the central rings of the AF are involved in the interaction with the HEM group of the active site. The differences in the molecular structure of the AF affect their position regarding the HEM group. The resulting configurations presented considerable variation in the amino acids and the position of the coupling. The charge transfer values showed that there is oxidative damage inside the active site and that the HEM group is responsible for the main charge transferences.

Aims To determine the prevalence and characteristics of bicuspid aortic valve (BAV) among elite athletes and to analyse the effect of long-term exercise training on their aortas. Methods and results Consecutive BAV and tricuspid aortic valve (TAV) elite athletes from a population of 5136 athletes evaluated at the Sports Medicine Center of the Spanish National Sports Council were identified using echocardiography. A total of 41 BAV elite athletes were matched with 41 TAV elite athletes, and 41 BAV non-athletic patients from three Spanish tertiary hospitals. Sixteen BAV elite athletes who had undergone at least two cardiac evaluations separated by more than 3 years were selected to assess their clinical course. The prevalence of BAV in elite athletes was 0.8%. The proximal ascending aorta was larger for both BAV groups in comparison to TAV athletes (P = 0.001). No differences in aortic diameters were found between BAV athletes and BAV non-athletes. In BAV elite athletes, the annual growth rates for aortic annulus, sinuses of Valsalva, sinotubular junction, and proximal ascending aorta were 0.04 +/- 0.24, 0.11 +/- 0.59, 0.14 +/- 0.38, and 0.21 +/- 0.44 mm/year, respectively. Aortic regurgitation was the only functional abnormality, but no significant progression was found. Conclusion High-intensity training and sports competition may not aggravate BAV condition during elite athletes' careers. BAV elite athletes with mild-to-moderately dilated aortas may engage in high dynamic cardiovascular exercise without adverse consequences, although an echocardiographic follow-up is recommended.

Los tratamientos actuales de la estenosis aórtica (EAo) grave incluyen el implante percutáneo de válvula aórtica (TAVI) y la cirugía de sustitución valvular aórtica (SVAo). El objetivo es describir la evolución de los pacientes con EAo grave tras la indicación de intervención, las variables que influyen en su pronóstico y los determinantes de un tiempo de espera superior a 2 meses. Subanálisis del registro IDEAS (Influencia del Diagnóstico de Estenosis Aórtica Severa) en los pacientes a los que se indicó intervención. De 726 pacientes con EAo grave diagnosticada en enero de 2014, se indicó intervención a 300 que son el foco del presente estudio. La media de edad era 74,0 ± 9,7 años. Se intervino a 258 pacientes (86,0%): 59 con TAVI y 199 con SVAo. Al año, 42 (14,0%) continuaban sin intervención, ya sea por seguir en espera (34) o haber fallecido (8). La mitad de los pacientes que murieron antes del procedimiento fallecieron en los primeros 100 días. El tiempo hasta la intervención fue 2,9 ± 1,6 meses para el TAVI y 3,5 ± 0,2 meses para la SVAo (p = 0,03). Los predictores de mortalidad independientes fueron el sexo masculino (HR = 2,6; IC95%, 1,1-6,0), la insuficiencia mitral moderada-grave (HR = 2,6; IC95%, 1,5-4,5), la movilidad reducida (HR = 4,6; IC95%, 1,7-12,6) y la falta de intervención (HR = 2,3; IC95%, 1,02-5,03). Los pacientes con EAo grave en espera de intervención tienen alto riesgo de mortalidad. Hay indicadores clínicos asociados con peor pronóstico que podrían indicar la necesidad de una intervención precoz. Current therapeutic options for severe aortic stenosis (AS) include transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). Our aim was to describe the prognosis of patients with severe AS after the decision to perform an intervention, to study the variables influencing their prognosis, and to describe the determinants of waiting time > 2 months. Subanalysis of the IDEAS (Influence of the Severe Aortic Stenosis Diagnosis) registry in patients indicated for TAVI or SAVR. Of 726 patients with severe AS diagnosed in January 2014, the decision to perform an intervention was made in 300, who were included in the present study. The mean age was 74.0 ± 9.7 years. A total of 258 (86.0%) underwent an intervention: 59 TAVI and 199 SAVR. At the end of the year, 42 patients (14.0%) with an indication for an intervention did not receive it, either because they remained on the waiting list (34 patients) or died while waiting for the procedure (8 patients). Of the patients who died while on the waiting list, half did so in the first 100 days. The mean waiting time was 2.9 ± 1.6 for TAVI and 3.5 ± 0.2 months for SAVR (P = .03). The independent predictors of mortality were male sex (HR, 2.6; 95%CI, 1.1-6.0), moderate-severe mitral regurgitation (HR, 2.6; 95%CI, 1.5-4.5), reduced mobility (HR, 4.6; 95%CI, 1.7-12.6), and nonintervention (HR, 2.3; 95%CI, 1.02-5.03). Patients with severe aortic stenosis awaiting therapeutic procedures have a high mortality risk. Some clinical indicators predict a worse prognosis and suggest the need for early intervention. Full English text available from: www.revespcardiol.org/en

A multiscale description of (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT6) ceramic is presented. High piezoelectric and electromechanical parameters (d33 = 167 pC/N, kt = 48.6%) were experimentally determined. The ceramic’s crystal structure, after poling, was determined from synchrotron X-ray diffraction. The Rietveld analysis reveals a highly textured BNBT6 perovskite with R3c symmetry. μ-X ray fluorescence on both unpoled and poled ceramics provided evidence of micrometric inhomogeneities in the elemental fluorescence intensities. μ-X ray absorption near edge spectroscopy (μ-XANES) at Ti K-edge spectra present anomalous absorption intensities in some energy intervals. First-principles modeling and linear combination analysis of μ-XANES spectra suggest local variations in the structure of the oxygen octahedron around titanium. The integrated analysis of experiments points toward the existence of micrometric clusters with an enrichment of Bi-O vacancies, distributed randomly at distances of tens of microns. Mentioned microstructural characteristics are consistent with the experimentally determined high piezoelectric and electromechanical parameters.

Se describe una nueva estrategia para la síntesis de multiferroicos monofásicos mediante el diseño asistido por computadora. Hoy en día existe un gran interés científico en el logro de tales compuestos, debido a sus potenciales aplicaciones dentro de la nanotecnología. Se aborda el tema de la dificultad de obtención de materiales magnetoeléctricos monofásicos a temperatura ambiente. Se enumeran los requisitos para que un material cumpla con esta propiedad desde el punto de vista químico, estructural y eléctrico. Se presentan algunos ejemplos de cerámicos multiferroicos y sus rasgos principales. Se propone la búsqueda de magnetoeléctricos multiferroicos dentro de la familia de las cerámicas de Aurivillius. Se plantea una estrategia novedosa, basada en la modelación teórica, para el logro de compuestos con características superiores dentro de dicha familia. DOI: https://doi.org/10.54167/tecnociencia.v1i2.49

Anthocyanins are water-soluble phenolic pigments. However, their poor solubility in lipidic media limits their use. This hurdle can be overcome with the lipophilization of anthocyanins, which consists of adding an aliphatic chain to a hydrophilic compound, in order to increase its solubility in lipids. Still, the unspecific chemical lipophilization of anthocyanin-esters produces molecules with different properties from their precursors. In this work, experimental changes of anthocyanin-esters obtained by chemical lipophilization are investigated in silico aiming specifically at observing their molecular behavior and comparing it with their anthocyanin precursor. Thus, the analysis of delphinidin 3-O-sambubioside and its esters employing Density Functional Theory (DFT) methods, such as the hybrid functional B3LYP in combination with the 6-31++G(d,p) Pople basis set, provides the ground state properties, the local reactivity and the molecular orbitals (MOs) of these compounds. Excited states properties were analyzed by TD-DFT with the B3LYP functional, and the M06 and M06-2X meta-GGA functionals. Local reactivity calculations showed that the electrophilic site for all the anthocyanin-esters was the same as the one for the anthocyanin precursor, however the nucleophilic site changed depending localization of the esterification. TD-DFT results indicate that the place of esterification could change the electronic transitions and the MOs spatial distribution.

Introduction and objectives: Current therapeutic options for severe aortic stenosis (AS) include transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). Our aim was to describe the prognosis of patients with severe AS after the decision to perform an intervention, to study the variables influencing their prognosis, and to describe the determinants of waiting time > 2 months. Methods: Subanalysis of the IDEAS (Influence of the Severe Aortic Stenosis Diagnosis) registry in patients indicated for TAVI or SAVR. Results: Of 726 patients with severe AS diagnosed in January 2014, the decision to perform an intervention was made in 300, who were included in the present study. The mean age was 74.0 +/- 9.7 years. A total of 258 (86.0%) underwent an intervention: 59 TAVI and 199 SAVR. At the end of the year, 42 patients (14.0%) with an indication for an intervention did not receive it, either because they remained on the waiting list (34 patients) or died while waiting for the procedure (8 patients). Of the patients who died while on the waiting list, half did so in the first 100 days. The mean waiting time was 2.9 +/- 1.6 for TAVI and 3.5 +/- 0.2 months for SAVR (P = .03). The independent predictors of mortality were male sex (HR, 2.6; 95% CI, 1.1-6.0), moderate-severe mitral regurgitation (HR, 2.6; 95% CI, 1.5-4.5), reduced mobility (HR, 4.6; 95% CI, 1.7-12.6), and nonintervention (HR, 2.3; 95% CI, 1.02-5.03). Conclusions: Patients with severe aortic stenosis awaiting therapeutic procedures have a high mortality risk. Some clinical indicators predict a worse prognosis and suggest the need for early intervention. (C) 2018 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S.L.U. All rights reserved.

The Cave of Swords was discovered in 1910 at Naica, Chihuahua, México. During the last century, human presence has changed the microclimate conditions inside this cave, raising the question of whether anthropogenic action resulted in the deterioration of its gypsum single crystals and in the deposition of impurities on their surfaces. The present work provides a detailed characterization of representative samples of this cave and suggests an answer to the origin of the impurities on the surface of these nature-made large crystals. Laboratory and synchrotron characterization techniques are applied. For the first time, the samples single-crystal nature and the fragmentation effect of impurities are characterized. Synchrotron light diffraction measurements performed on a collection of characteristic samples consistently reveal sharp textures, with crystal reciprocal vectors [0,1,0] preferably perpendicular to the samples principal cleavage planes and orientation widths averaging 8°. X-ray diffraction identifies galena, sphalerite, hematite, goethite and cuprite on the crystals’ surface. Diffraction results indicate no correlation between the number of phases of impurities present and crystallinity. Micro X-ray fluorescence clarifies the elemental spatial distribution. The correlations between the elemental distributions confirm the phase identification obtained by diffraction. For Mn and Pb, the correlations point to the presence of amorphous oxides. Minor phases’ characterization suggests they have been deposited on iron oxy-hydroxide substrates. All the identified phases correspond to minerals that were abundantly present in Naica ore deposit before any anthropogenic activity. The impurities on the surface of gypsum crystals at the Cave of Swords were not produced by human presence.

AimsAortic stenosis (AS) is the most frequent valvular disease in developed countries. As society grows older, the prevalence of AS increases. However, the real burden, current aetiology, severity distribution, and echocardiographic patterns of AS are not fully clear. The aim of the present study is to provide an accurate overall picture of AS, focusing on its epidemiology, aetiology, and echocardiographic features.Methods and resultsA total of 29 502 consecutive echocardiograpies were prospectively included in this multicentre study. The present sample was composed of patients with advanced age (mean 75.2 years) and similar gender distribution. High proportion (7.2%) showed any grade of AS, with important number of patients (2.8%) presenting severe AS, most of them aged 75 years or more. Coexisting valvular disease appeared in almost half of the sample (49.6%), being the most frequently diagnosed aortic regurgitation (AR) (22%) followed by mitral regurgitation (MR) (15.6%). Degenerative aetiology was found in the vast majority (93.4%) of the studies whereas rheumatic is currently infrequent (3.35%). Low flow-low gradient (LFLG) appeared in 24.6% of patients with severe AS. Atrial fibrillation (23.1% vs. 11.6%; P = 0.002), MR (23.3% vs. 15.1%; P = 0.018), and right ventricle dysfunction (13.3% vs. 5.2%; P = 0.003) appeared frequently in LFLG group.ConclusionsBurden of AS is higher than previously assumed. Degenerative aetiology is the main cause of AS. Most of the patients are elder with high prevalence of significant co-existing valvular disease. LFLG severe AS is present in an important proportion of patients, showing high grade of left ventricle remodelling.