Naica's "Cueva de los Cristales": Synchrotron radiation characterization of the wall-crystal interface

Naica's "Cueva de los Cristales" was discovered in 2000. It has been considered particularly interesting for its beauty and the challenges it poses to crystallography. This article focuses on the study of the wall-selenite interface by various techniques, particularly X-ray diffraction (XRD), scanning electron microscopy (SEM), with emphasis on micro-X-ray fluorescence (micro-XRF) and micro-X-ray absorption near edge structure (micro-XANES). The main phases calcite, quartz, goethite and montmorillonite were identified by XRD, as well as the association of crystalline and amorphous minor and trace phases of Zn, Mn, Cu, As and Pb. The latter were identified in micro-XRF maps and micro-XANES spectra. The results for the morphology and the chemical description of the crystal-wall interface may contribute to propose a nucleation and growth mechanism for Naica megacrystals

Discourse Analysis and Terminology in Languages for Specific Purposes

Aquest importantíssim recull conté estudis i reflexions sobre temes rellevants en la recerca sobre LSP: anglès mèdic, el llenguatge de la publicitat i periodístic, telecomunicacions i terminologia informàtica, llenguatge comercial i jurídic... Malgrat que gran part dels treballs aplegats es refereixen a l'anglès, també hi ha que tracten l'alemany, francès i altres llengües. Conté textos en anglès, francés, portuguès i castellà

Developments and applications of the OPTIMADE API for materials discovery, design, and data exchange

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

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Innovación, desarrollo tecnológico y gestión : una construcción desde la investigación

Libro que compila investigaciones de carácter aplicadas y descriptivas en materia de innovación y desarrollo tecnológico, gestión organizacional y empresarial orientada a productividad, rentabilidad, competitividad y sostenibilidadBook that compiles researches of applied and descriptive character in the matter of innovation and technological development, organizational and business management oriented to productivity, profitability, competitiveness and sustainabilityCapítulo 1. Material compuesto para la construcción a partir de la celulosa del papel y cartón reciclado / Carlos Arturo Tamayo S; Nicolás Montero Camacho; Fredy Antonio Herrera -- Capítulo 2. Tecnologías de conservación para base de sopa de frijol rojo (phaseolus vulgaris) y vegetales / Yaceris Castro Escorcia; Teresa Altamar Pérez; Enedys Florez Cortés; Ángela Ortiz Ruiz. Capítulo 3. Utilización de harina compuesta de frijol caupi (vigna unguiculata) en masas para alimentos congelados / Marcela Villalba Cadavid; Matilde Rodríguez Muñoz; Beatriz Fernández; Juan Mendoza Combatt -- Capítulo 4. Elaboración de biorrecubrimiento comestible para carne de hamburguesa como alternativa de conservación y condimento natural / Camila Andrea Ubaque Beltrán. CAPÍTULO 5. Identificación de alternativas de industrialización de productos y subproductos agroindustriales en nuevos materiales bio poliméricos / Luz Henao Díaz; Deya Pérez Zúñiga; Herold Arango Gómez. Capítulo 6. SCADA inalámbrico para monitoreo de sistemas de energía solar / Nelson Giovanni Agudelo Cristancho; Juan Carlos Amezquita Tovar; Ángela María Montoya Castro. -- Capítulo 7. Evaluación de la calidad del agua para consumo humano del corregimiento de Jaraquiel, Montería, Córdoba / Carlos Burgos Galeano; Álvaro Aleán Vásquez; Paula Estrada Palencia -- Capítulo 8. Optimización del sistema de abastecimiento de agua en la comunidad de Jaraquel, Montería Colombia / Carlos Burgos Galeano; Pedro Ramos Tejada; Paula Estrada Palencia; Jhon Sánchez Correa. -- Capítulo 9. Ejecución y sostenibilidad de proyectos productivos en la microrregión cafetera del municipio de Ciénaga, Magdalena / Sugey Issa Fontalvo; Eduardo Robles Panetta; Freddy González Castillo. -- Capítulo 10. Aplicación del método cualitativo por puntos para determinar aspirante favorito a cargos directivos en IES / Zamir Martelo Ballesteros; Raúl Martelo Gómez; Luis Tovar Garrido; Natividad Villabona Gómez; David Franco Borré. -- Capítulo 11 Responsabilidad social en comunidades indígenas orientada al diseño de automatización de válvulas del gasoducto Riohacha-Maicao / Gelvis Melo Freile; César Rivera Romero; Jesús García Guiliany. -- Capítulo 12 Fortalecimiento de la gestión económica de las Mipymes a través de la consultoría / Gloria Amparo Acosta Romero; Mónica Andrade Ríos; Karen Roxana Sánchez. -- Capítulo 13. El compromiso como valor en la responsabilidad social universitaria / Maura Quintero Gutiérrez, Dubys Villarreal Torres; Jesús García Guiliany; Annherys Paz Marcano; Marieth Orcasitas Peñaloza. -- Capítulo 14. Educación financiera como alternativa de desarrollo económico y social para el distrito de Riohacha / Henitzo Martínez Pinedo; Darcy Luz Mendoza; Martha Jaramillo Acosta; Edwin Salas Solano. -- Capítulo 15. Tecnologías de información y comunicación en proceso contable y financiero en pymes del sector turístico / Martha Josefina Castrillón Rois; Edilberto Rafael Santos Moreno; Lorena Esther Gómez Bermúdez; Génesis Barros González. -- Capítulo 16. Aplicación de brainstorming y problem trees para determinar factores que inciden en enseñanza del inglés / Jesús Llerena; Raúl J. Martelo; Jhon Cuesta; Javier Pinedo; David Franco.-- Capítulo 17. Incidencia del marketing en las microempresas del sector comercio en Rionegro Antioquia: conceptualización / Santiago Álzate Carmona; María Yamile Mazo Gil; Leidy García Jaramillo. -- Capítulo 18. Turismo en el Cabo de la Vela: un acercamiento entre los imaginarios turísticos de los visitantes y la creencia de Jepirra, territorio sagrado / María Laura Aponte Aarón; Esmerlis Camargo Torres. -- Capítulo 19. Caracterización de la actividad turística en buenaventura y su integración con las comunidades locales / Víctor Cándelo Aragón; Henry Orobio García; Luis Montaño Aguilar. -- Capítulo 20. Plataforma de comercialización electrónica de un centro de abastos / Karen Ávila Suarez; Mauro Reyes Ortiz. -- Capítulo 21. El teletrabajo en la gestión administrativa / Estefanía Sandoval Cruz; René Alexander Guerrero Vergel. -- Capítulo 22. Gestión del conocimiento y alianzas estratégicas en los procesos de innovación tecnológica / Elder Rivero Gutiérrez; Fátima Bolaño Mendoza. -- Capítulo 23. Competitividad e innovación en el aprendiz SENA: perspectivas de formación / Elizabeth Tuberquia Vanegas; René Alexander Guerrero Vergel. -- Capítulo 24. Bomba de riego por goteo solar, una alternativa para aumentar la eficiencia energética en las unidades acuícolas / Sergio Gabriel Brito Brito; Daldo Ricardo Araujo Vidal; Nicolás Annicharico Jiménez. -- Capítulo 25. Herramienta digital de consultas contables y tributarias para unidades productivas creadas en el fondo emprender / Elkin Fuentes Jiménez; Alda Pérez Campuzano; Marieth Orcasitas Peñaloza; Olga Elena Guerra ArmentaPrimera ediciónna347 página

Ferroelectrics under the synchrotron light: A Review

Currently, an intensive search for high-performance lead-free ferroelectric materials is taking place. ABO perovskites (A = Ba, Bi, Ca, K and Na; B = Fe, Nb, Ti, and Zr) appear as promising candidates. Understanding the structure-function relationship is mandatory, and, in this field, the roles of long- and short-range crystal orders and interactions are decisive. In this review, recent advances in the global and local characterization of ferroelectric materials by synchrotron light diffraction, scattering and absorption are analyzed. Single- and poly-crystal synchrotron diffraction studies allow high-resolution investigations regarding the long-range average position of ions and subtle global symmetry break-downs. Ferroelectric materials, under the action of electric fields, undergo crystal symmetry, crystallite/domain orientation distribution and strain condition transformations. Methodological aspects of monitoring these processes are discussed. Two-dimensional diffraction clarify larger scale ordering: polycrystal texture is measured from the intensities distribution along the Debye rings. Local order is investigated by diffuse scattering (DS) and X-ray absorption fine structure (XAFS) experiments. DS provides information about thermal, chemical and displacive low-dimensional disorders. XAFS investigation of ferroelectrics reveals local B-cation off-centering and oxidation state. This technique has the advantage of being element-selective. Representative reports of the mentioned studies are described.Funding from Project CONACYT 257912 “Representación y pronóstico de las propiedades físicas de los materiales mono- y policristalinos” is recognized. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe

Chihuahua, Tierra de Cristales 2014, Año Internacional de la Cristalografía

Se presenta la definición de cristal, su diferencia respecto del vidrio, y la historia del descubrimiento de la difracción de rayos X, cuyo centenario ha motivado la declaración del año 2014 como Año Internacional de la Cristalografía. Se muestran los experimentos de Max von Laue, así como de William H. y William L. Bragg y se explican mediante la analogía con la difracción de la luz visible. Se exhiben las estructuras cristalinas de numerosos materiales importantes para el ser humano, su evolución y su desarrollo. Se exponen qué son los monocristales y los policristales, así como las diferentes estructuras cristalinas del carbono. Se explica cómo el progreso de la cristalografía, junto con la mecánica cuántica, han conducido a la tecnología moderna de la computación y las comunicaciones, comenzando desde el diodo semiconductor y el transistor hasta los modernos microprocesadores. Se describen la ferroelectricidad y la superconductividad y sus aplicaciones. Por último, se divulgan ejemplos del desarrollo moderno de la nanotecnología. Se explica cómo un monocristal nace y crece a partir de un nanocristal, para terminar con la demostración de que Chihuahua es Tierra de Cristales por la presencia de la Cueva de los Cristales Gigantes en Naica. Abstract It is presented the definition of a crystal, the differences with glass, and the history of the discovery of the X-ray diffraction, whose centenary has led to the declaration of 2014 as the International Year of Crystallography. The experiments of Max von Laue, as well as of William H. and William L. Bragg are described and explained using an analogy with the diffraction of visible light. The crystal structures of several important materials for human kind, their evolution and development are exhibited. The questions of what are single crystals and what are polycrystals are answered, as well as the different crystal structures of carbon atoms can form. The process of how Crystallography, along with quantum mechanics have led to the modern technology of computing and communications is detailed starting from semiconductor diodes and transistors up to the advent of modern microprocessors. The ferroelectric and superconductor materials are described, and their applications. Finally, examples of modern development due to nanotechnology are disclosed. The explanation of how a single crystal is born and grows from a nanocrystal is provided, finishing with the demonstration that Chihuahua is a land of crystals because of the presence of the Giant Crystals Cave at Naica. Keywords: Naica, crystallography, crystal structure, selenite

Evolution of the Atonishing Naica Giant Crystals in Chihuahua, Mexico

Calcium sulfate (CaSO4) is one of the most common evaporites found in the earth’s crust. It can be found as four main variations: gypsum (CaSO4·2H2O), bassanite (CaSO4 ·0.5H2O), soluble anhydrite, and insoluble anhydrite (CaSO4), being the key difference the hydration state of the sulfate mineral. Naica giant crystals’ growth starts from a supersaturated solution in a delicate thermodynamic balance close to equilibrium, where gypsum can form nanocrystals able to grow up to 11–12 m long. The growth rates are reported to be as slow as (1.4 ± 0.2) × 10−5 nm/s, taking thousands of years to form crystals with a unique smoothness and diaphaneity, which may or may not include solid or liquid inclusions. Conservation efforts can be traced back to other gypsum structures found prior to Naica’s. Furthermore, in the last two decades, several authors have explored the unique requirements in which these crystals grow, the characterization of their environment and microclimatic conditions, and the prediction of deterioration scenarios. We present a state-of-the-art review on the mentioned topics. Beyond the findings on the origin, in this work we present the current state and the foreseeable future of these astounding crystals.The support provided by CONACYT Project No. 183706, the proposals SSRL 3939, the ESRF HG-77, Elettra Sincrotrone-Trieste 20155328, as well as by the International Centre for Theoretical Physics (ICTP) are acknowledged. Special thanks to Manuel Reyes-Cortés, who provided some of the key research samples and supported their selection and analysis. The authors thank the cooperation of the management of the Peñoles company, the Desert Museum of Ciudad Delicias, Chihuahua, the Harvard Museum of Natural History, and the Faculty of Engineering of the Autonomous University of Chihuahua for providing essential specimens for the study. The authors thank the anonymous referees for their helpful suggestions

Theoretical Characterization by Density Functional Theory (DFT) of Delphinidin 3-O-Sambubioside and Its Esters Obtained by Chemical Lipophilization

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

Nueva ruta para la obtención de multiferroicos magnetoeléctricos monofásicos

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.v1i2.4