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Chemistry and Interfacial Structure Promoting Quasi-van der Waals Epitaxial Growth of WS2 Nanosheets on Sapphire for Prospective Application in Field-Effect Transistors
No full textHow do chemical and structural modifications to the supporting crystal surface affect the subsequent van der Waals (vdW) or quasi(Q)-vdW epitaxial growth of 2D nanocrystals? Developing an atomic-scale picture of such an interfacial system is crucial for understanding its impact on the physical and chemical properties of the supported 2D materials. The elucidation of the interfacial structure and chemistry needed to promote the Q-vdW epitaxial growth of 2D tungsten disulfide (WS2) nanocrystals contributes to the growth mechanism understanding, thus pushing forward the integration of such atomically thin semiconductors toward real field-effect transistor applications. In addition to an atomic-force microscopy top view, we showcase a combination of X-ray techniques for a top-to-bottom investigation of the complexities of the buried interface structures. This approach uses X-ray photoelectron spectroscopy, X-ray standing wave excited X-ray fluorescence, and crystal truncation rod scattering to produce a highly resolved chemical-state-specific 3D atomic map for the extended interface structure of WS2/α-Al2O3(001). Employing these detailed analysis methods, along with density functional theory to further refine the picoscale structure, we demonstrate how two different types of interface engineering during the pregrowth stage lead to significant differences in the chemical and structural modifications to the terminal surface of c-face sapphire, which in turn leads to substantial differences in the submonolayer growth of supported WS2 2D nanocrystals in terms of lateral domain sizes, epitaxial registry, vdW gaps, and stability. © 2025 American Chemical Society
Archaeological Analysis of the Newly Discovered Tomb with a Relief of a Couple at the Funerary Area of Porta Sarno in Pompeii
Get PDFIn July 2024, the “Investigating the Archaeology of Death in Pompeii Research Project” carried out a scientific and methodical excavation of the areas outside two of the gates to the city of Pompeii. One of them is the funerary area of Porta Nola (next to the tomb of Obellio Firmo) and the other is outside Porta Sarno area (east of the tomb of Marcus Venerius Secundius). The investigated funerary area to the east of Porta Sarno corresponds with the area excavated in 1998 for the construction of the double Circumvesuviana rails. The 1998 excavations recorded the presence of more than 50 cremation burial sites, marked by stelae (columelle) and a monument with an arch, which are delineated by a boundary wall. The tombs were initially dated to the Late Republican period. In order to carry out comprehensive studies of the funerary area uncovered in 1998, a four metre by four metre trench was stratigraphically excavated. This investigation allowed mapping of the area and the carrying out of archaeological analysis and bioarchaeological studies in order to answer the questions that guided our archaeological research, such as whether the funerary area was abandoned and, if so, when? What was the chronological succession, monumentality, and prestige of this funerary space? Was it a single family and private funerary enclosure, or was it an open public space? How were this funerary area and the spaces destined to preserve the memory of the deceased managed? How were the funerary and mortuary rituals and gestures articulated and what did they consist of? Our methodical excavation discovered a monumental tomb which allows us to answer many of the questions raised by our research. This extraordinary monument consists of a wide wall with several niches containing the cremated remains of the deceased built into its structure and which is crowned by a relief of a young couple. The symbolism of the carved accessories of the wife may identify her as a priestess of Ceres. Additionally, the quality of the carving in the sculptures and their archaic characteristics suggest a Republic period dating, which is uncommon in southern Italy
Calvo Gómez, J. A., Sánchez-Sánchez, D., & Sánchez Hernández, J. A. (coord.) (2024). El patrimonio cultural inmaterial. Recursos para la investigación, gestión y regulación jurídica. Tirant Humanidades
Get PDFReseña de libro. Calvo Gómez, J. A., Sánchez-Sánchez, D., & Sánchez Hernández, J. A. (coord.) (2024). El patrimonio cultural inmaterial. Recursos para la investigación, gestión y regulación jurídica. Tirant Humanidades
Meropenem-induced cross-protection in Salmonella enterica resistant variants: Insights from adaptive laboratory evolution and whole genome sequencing
Get PDFAdaptive laboratory evolution (ALE) assay provides a deep understanding of the genetic mechanisms and processes involved in bacterial responses. This study aimed to obtain resistant-variants (RVs) of Salmonella enterica subsp. enterica Typhimurium (SeT) and Enteritidis (SeE) after ALE assays with meropenem (MPM); to identify genetic modifications of RVs responsible for their increased resistance; and to evaluate their cross-protection against antibiotics and food preservatives (heat and carvacrol). Five MPM-RVs from SeT (SeT_M1-5) and one from SeE (SeE_M5) showed a 100 % increase in MPM minimum inhibitory concentrations (from 0.0312 to 0.0625 μg/mL). MPM-RVs had lower maximum growth rates and/or longer lag times, except in SeT_M5 and SeE_M3, which maintained or even improved growth fitness in the presence of MPM. Whole genome sequencing of RVs revealed single mutations in AMR-related and -unrelated genes in most MPM-RVs: spoT in SeT_M1, glnA in SeT_M2, thrS in SeT_M4 and SeE_M2, and mrdA in SeT_M5, SeE_M3 and SeE_M5. Two mutations were identified in SeT_M3 and SeE_M4: spoT and znuA in SeT_M3 and AWJ12_RS14025 and rfbF in SeE_M4. The individual mutations resulted in cross-protection to at least one of the antibiotics tested and/or heat (reductions of up to 3.8–4.3 cycles of inactivation for MPM-RVs in contrast to 4.7 and 5.3 cycles for SeE and SeT, respectively) and/or carvacrol (3.4–3.7 cycles for MPM-RVs in contrast to 4.4 cycles for SeT). These findings highlight the importance of preventing the emergence of resistant bacterial variants, considering the cross-protection to other antibiotics and food preservatives, which plays an important role in spreading resistance in food chain
Comprehensive Proposal for the Rehabilitation of the Acequia del Diablo (Teruel, Spain): Revitalizing Irrigation and Cultural Heritage
Get PDFThe preservation of historic irrigation infrastructure is vital for sustainable water management, especially in regions grappling with rural depopulation, land degradation, and wildfire risk. This study presents a rehabilitation framework for the Acequia del Diablo (Teruel, Spain), a centuries-old gravity-fed canal that supported 60 hectares of agriculture and contributed to ecological connectivity. Its deterioration—following landslides in 1992 and water source loss in 2020—has led to land abandonment, biodiversity decline, and increased wildfire vulnerability. The proposed solution, centered on restoring the original intake at the Azud de Fonseca and stabilizing damaged sections, reestablishes water autonomy and integrates heritage conservation into water governance. A multi-criteria analysis identified this gravity-based alternative as the most technically, economically, and environmentally viable. Drawing from precedents in the literature, the conservation and rehabilitation of historical irrigation systems play a crucial role in sustainable water management in rural areas; this initiative offers a replicable model for other Mediterranean and semi-arid areas. However, challenges include engineering complexity in unstable terrain, administrative delays, and long-term maintenance. Despite these, this intervention enhances rural resilience, wildfire prevention, and biodiversity, while aligning with circular economy principles and European Green Deal objectives
Electronic structure tunability of carbon-based 1D-polymers combining cross-conjugation and nitrogen doping
Get PDFQuasi-one-dimensional polymer structures with extended π-electron systems stand out due to their remarkable application in light-emitting diodes and devices. Upon smart choice of their building units, such carbon-based organic nanoarchitectures provide excellent optoelectronic properties by tuning their dimensionality, atomic structure or intrinsic doping. Here, we generate and study three canonical cross-conjugated quasi one-dimensional chains with controlled nitrogen intrinsic doping, which is selectively introduced into their poly-phenylene backbones. By means of scanning tunneling microscopy and spectroscopy we corroborate that the cross-conjugation that break the chain linearity is exclusively responsible of the electronic confinement in the straight segments. Moreover, we demonstrate that the LUMO state exhibits similar spatial distribution for the cross-conjugated polymers independently of the pyridine content of the initial precursor. Despite this coincidence, the semiconducting character and other relevant electronic properties of the polymers are found to depend both on the chain morphology and on the precise position and number of doping nitrogen atoms synthetically introduced into the molecular precursors. We compare these results to related previous studies, which allows us to unambiguously validate the opto-electronic tunability upon the choice of the polymers’ building units
Kinematics of the Cretaceous Rifting in the Chainons Béarnais and Bigorre Basin (North Pyrenean Zone): Insights From Magnetic Fabrics and Mineral Anisotropy
Get PDFThe North Pyrenean Zone results from the Late Cretaceous‐Cenozoic inversion of the Mesozoic rift system extending along the Iberia‐Europe plate boundary. The western part of this inverted rift (from the Tardets‐Mauléon basin in the West to the Bigorre basin in the East) is strongly decoupled from the basement along Upper Triassic evaporites and slightly, internally overprinted by orogenic processes. These conditions make the area an ideal candidate for the study of rift‐related structures and mineral fabrics registering the kinematics of the rifting process. This work focuses on the study of meso and micro‐scale rift inheritance through a combination of structural analysis, anisotropy of magnetic susceptibility (AMS) and mineral shape fabrics extracted from X‐Ray microtomography analysis. Previous AMS results (Mauléon basin) are integrated with data from 64 new AMS sites, acquired across both the Mesozoic, syn‐rift cover and the Paleozoic basement. In syn‐rift units, magnetic and mineral fabrics are in agreement and at a great extent inherited from syn‐ and post‐rift stages. The compressional overprint of the Late‐Cretaceous‐Cenozoic inversion is limited and localizes along the south‐western margin of the inverted basin. In the Paleozoic, a partial overprint of Mesozoic extension on AMS occurs in areas where rift‐related peak temperatures exceeded ∼350°C. Rift‐related mineral and magnetic lineations reveal a regional and constant through time NNW‐SSE to NE‐SW extension that attests this ample domain of the Pyrenean rift opened under a roughly orthogonal or slightly oblique rifting. Its easternmost part registered a partitioning between N‐S and NW‐SE extension directions, likely controlled by pre‐rift faulting
Viabilidad de Brisalia S.L.
Get PDFEste Trabajo Fin de Grado tiene como objetivo valorar la viabilidad de la puesta en marcha de una empresa que ofrece principalmente cursos de cocina para grupos reducidos y posteriormente la degustación por parte de los clientes de los platos que cada uno ha elaborado. Para ello se realizará el análisis del entorno general y específico en el que se encontraría este negocio, el análisis del marco legal actual y el desarrollo de un plan de marketing y operativo. Por último, se estudiará lo referido a la parte de recursos humanos y el plan económico-financiero. Con ello se calculará las necesidades que hacen falta para llevar a cabo este negocio, tanto monetarias, fuentes de financiación y previsiones para los primeros años de vida de la empresa. Con las conclusiones podremos ver si la sociedad está dispuesta a consumir este servicio y por tanto la empresa podría ser viable en términos económicos. <br /
Evaluación capilaroscópica en pacientes con diabetes tipo 1: relación con el control glucémico y las complicaciones microvasculares
Get PDFIntroducción: La diabetes mellitus tipo 1 (DM1) es una enfermedad metabólica crónica caracterizada por un estado sostenido de hiperglucemia, que provoca daño progresivo en la microvasculatura, responsable de complicaciones como la retinopatía o la nefropatía. Estas alteraciones microvasculares pueden visualizarse de forma no invasiva mediante la videocapilaroscopia del pliegue ungueal (NVC). Su análisis podría constituir una herramienta útil para la detección precoz de dichas complicaciones.Objetivo: Evaluar si alteraciones capilaroscópicas del lecho ungueal se asocian con el grado de control glucémico en pacientes con DM1, la duración de la enfermedad y la presencia de retinopatía diabética (RD) y enfermedad renal crónica (ERC).Métodos: Este estudio transversal multicéntrico incluyó a 181 pacientes con diabetes mellitus tipo 1 de al menos 10 años de evolución. Se realizó NVC a todos los participantes analizada mediante inteligencia artificial con la plataforma Capillary.io, obteniendo datos cuantitativos de alteraciones capilaroscópicas. Además, se recopilaron datos clínicos y analíticos. El análisis estadístico incluyó un estudio descriptivo inicial, un análisis comparativo multivariante y un análisis de precisión mediante modelos de aprendizaje automático.Resultados: Los pacientes con hemoglobina glicosilada (HbA1c) ≥7% mostraron significativamente menor densidad capilar y mayor área de dilataciones. La duración de la DM1 superior a 20 años se asoció también con menor densidad, al igual que la RD además de un incremento del área de dilataciones. La ERC solo mostró asociación con mayor área de hemorragias. Los modelos predictivos basados en aprendizaje automático obtuvieron un F1-score de 0,79 para mal control glucémico y 0,64 para RD.Conclusión: La NVC constituye una herramienta prometedora para evaluar el daño microvascular crónico en DM1. Su correlación con el control metabólico y las complicaciones sugiere su utilidad potencial en la estratificación del riesgo vascular de forma no invasiva y reproducible.Palabras clave: Videocapilaroscopia, diabetes tipo 1, hemoglobina glicosilada, retinopatía diabética, enfermedad renal crónica. <br /
SÍNDROME DE GOLDENHAR: REVISIÓN BIBLIOGRÁFICA Y PRESENTACIÓN DE CASOS
Get PDFEl síndrome de Goldenhar, también conocido como síndrome óculo-auriculo-vertebral es un trastorno congénito poco frecuente que se caracteriza por anomalías auriculares, oculares y vertebrales. Su etiología se considera multifactorial ya que se han descrito casos de herencia autosómica dominante, recesiva, así como casos espontáneos estando todos ellos influidos por factores genéticos y ambientales. Su fisiopatología se relaciona con un desarrollo anormal del primer y segundo arco faríngeo alrededor de la cuarta semana de gestación. El diagnóstico se basa en la exploración física al nacimiento y se pueden incluir pruebas de imagen, por lo que su manejo involucra un abordaje multidisciplinar incluyendo genetistas, otorrinolaringólogos, cardiólogos, cirujanos plásticos y otros especialistas. Las opciones terapéuticas varían según la severidad del cuadro clínico, pudiendo incluir intervenciones quirúrgicas, audífonos, tratamiento de la patología ocular, entre otros. A pesar de que el S. Goldenhar puede conllevar implicaciones tanto físicas como funcionales, una detección precoz y un tratamiento adecuado mejoran la calidad de vida de los pacientes y de sus familias. <br /