Social distancing and testing as optimal strategies against the spread of COVID-19 in the Rio Grande Valley of Texas

At the beginning of August 2020, the Rio Grande Valley (RGV) of Texas experienced a rapid increase of coronavirus disease 2019 (abbreviated as COVID-19) cases and deaths. This study aims to determine the optimal levels of effective social distancing and testing to slow the virus spread at the outset of the pandemic. We use an age-stratified eight compartment epidemiological model to depict COVID-19 transmission in the community and within households. With a simulated 120-day outbreak period data we obtain a post 180-days period optimal control strategy solution. Our results show that easing social distancing between adults by the end of the 180-day period requires very strict testing a month later and then daily testing rates of 5% followed by isolation of positive cases. Relaxing social distancing rates in adults from 50% to 25% requires both children and seniors to maintain social distancing rates of 50% for nearly the entire period while maintaining maximum testing rates of children and seniors for 150 of the 180 days considered in this model. Children have higher contact rates which leads to transmission based on our model, emphasizing the need for caution when considering school reopenings

An Innovative 3D Printed Tooth Reduction Guide for Precise Dental Ceramic Veneers.

Tooth reduction guides allow clinicians to obtain the ideal space required for ceramic restorations. This case report describes a novel design (CAD) for an additive computer-aided manufactured (a-CAM) tooth reduction guide with channels that permitted access for the preparation and evaluation of the reduction with the same guide. The guide features innovative vertical and horizontal channels that permit comprehensive access for preparation and evaluation of the reduction with a periodontal probe, ensuring uniform tooth reduction and avoiding overpreparation. This approach was successfully applied to a female patient with non-carious lesions and white spot lesions, resulting in minimally invasive tooth preparations and hand-crafted laminate veneer restorations that met the patient's aesthetic demands while preserving tooth structure. Compared to traditional silicone reduction guides, this novel design offers greater flexibility, enabling clinicians to evaluate tooth reduction in all directions and providing a more comprehensive assessment. Overall, this 3D printed tooth reduction guide represents a significant advancement in dental restoration technology, offering clinicians a useful tool for achieving optimal outcomes with minimal tooth reduction. Future work is warranted to compare tooth reductions and preparation time for this guide to other 3D printed guides

Diagnostic Mock-Up as a Surgical Reduction Guide for Crown Lengthening: Technique Description and Case Report.

Background and Objectives: The report describes a technique using a diagnostic mock-up as a crown-lengthening surgical guide to improve the gingival architecture. Materials and Methods: The patient's primary concern was improving her smile due to her "gummy smile" and short clinical crowns. After clinical evaluation, surgical crown lengthening accompanied by maxillary central full-coverage single-unit prostheses and lateral incisor veneers was recommended. The diagnostic mock-up was placed in the patient's maxillary anterior region and used as a soft tissue reduction guide for the gingivectomy. Once the planned gingival architecture was achieved, a flap was reflected to proceed with ostectomy in order to obtain an appropriate alveolar bone crest level using the overlay. After six months, all-ceramic crowns and porcelain veneers were provided as permanent restorations. Results: A diagnostic mock-up fabricated with a putty guide directly from the diagnostic wax-up can be an adequate surgical guide for crown-lengthening procedures. The diagnostic wax-up was used to fabricate the diagnostic mock-up. These results suggested that it can be used as a crown-lengthening surgical guide to modify the gingival architecture. Several advantages of the overlay used in the aesthetic complex case include: (1) providing a preview of potential restorative outcomes, (2) allowing for the appropriate positioning of gingival margins and the desired alveolar bone crest level for the crown-lengthening procedure, and (3) serving as a provisional restoration after surgery. Conclusions: The use of a diagnostic mock-up, which was based on a diagnostic wax-up, as the surgical guide resulted in successful crown lengthening and provisional restorations. Thus, a diagnostic overlay can be a viable option as a surgical guide for crown lengthening

The Emerging Role of Protein Phosphorylation as a Critical Regulatory Mechanism Controlling Cellulose Biosynthesis

Plant cell walls are extracellular matrices that surround plant cells and critically influence basic cellular processes, such as cell division and expansion. Cellulose is a major constituent of plant cell walls, and this paracrystalline polysaccharide is synthesized at the plasma membrane by a large protein complex known as the cellulose synthase complex (CSC). Recent efforts have identified numerous protein components of the CSC, but relatively little is known about regulation of cellulose biosynthesis. Numerous phosphoproteomic surveys have identified phosphorylation events in CSC associated proteins, suggesting that protein phosphorylation may represent an important regulatory control of CSC activity. In this review, we discuss the composition and dynamics of the CSC in vivo, the catalogue of CSC phosphorylation sites that have been identified, the function of experimentally examined phosphorylation events, and potential kinases responsible for these phosphorylation events. Additionally, we discuss future directions in cellulose synthase kinase identification and functional analyses of CSC phosphorylation sites

Control automatico y servomecanismos para la alimentacion de caldera stirling

106 p.Debido a la gran necesidad de un mejor aprovechamiento de los recursos, una menor contaminación ambiental y disminuir los costos de producción, se ha decidido hacer un sistema de control automático en la producción de vapor. La gran demanda de los hidrocarburos, que son recursos no renovables y el elevado costo que estos significan para la industria, se están adaptando, generadores de vapor alimentados por combustibles naturales renovables. El desafío actual es la renovación constante e innovación de métodos; es por eso que hemos aceptado adherirnos a ello. Lo que encierra esta tesis es dar a conocer el método a seguir en un sistema de control de vapor automático en la alimentación de un generador de vapor. La presente tesis encierra los parámetros a la cual esta restringida una caldera en la generación de vapor, en función de su gasto. En primera instancia, se hace un análisis de la necesidad de la industria; lo que proporciona la cantidad de combustible a emplear y con ello el volumen de aire para la oxidación o combustión. Los combustibles empleados son: Cáscara de maravilla Pepa de uva Orujo de uva, los cuales se introducen en una mezcla de pequeñas partículas en cantidades convenientes para proporcionar los Kcal necesarios al consumo de vapor. Conjuntamente con la producción de vapor, se presenta la necesidad de tener en existencia un determinado volumen de H2O en estanque de acumulación, en la que se hace una relaci6n Aire combustible, Agua en funci6n de su gasto. Pese a la orientación fundamental práctica se ha considerado conveniente incluir aspectos básicos sobre elementos de la teoría, con el propósito de fundamentar las aplicaciones técnicas. Para mayor facilidad de comprensión se adjuntan planos, dibujos y bosquejos de la instalación. Se ha introducido en esta tesis un lenguaje claro y sencillo con el propósito de que pueda servir como base para muchos proyectos de innovación

Planificacion y desarrollo de la Industria Maquimsa

140 p.La gran competencia industrial que se esta viviendo, ha creado mentalidad en los empresarios, de resguardar al máximo su capital invertido, ya sea en maquinaria, equipos, edificios, etc. y alarga la vida útil de cada uno de ellos, pare así poder bajar sus costos de producción. Como también, de llevar una planificación y un control seguro de todos los procesos o actividades que se desean realizar, de tal manera de poder controlar cada elemento que pueda producir perdidas. Para llevar a cabo tales planes, es necesario tener un control adecuado de la aplicación de factores tan importantes como son la seguridad industrial, el control de perdidas y la manutención. Tomando en cuenta los factores ya analizados, se ha creado conveniente centralizar esta tesis en estos temas de vital importancia para la exigencia en el mercado y el avance a tecnología y si bien es cierto para nuestra formación como futuro profesional. La tesis comprenderá tres capítulos y un apéndice En el primer capitulo, se analizara conceptos y elementos teóricos de la seguridad industrial, para luego poder darle una aplicación en la industria, posteriormente en el capitulo 2, se realizara` el estudio de control de perdida en el cual se vera la factibilidad de crear un programa en el que se evalúa técnica y económicamente los temas anteriores. En este último capitulo, se realizan un estudio teórico y su respectiva aplicación en base a un programa de manutención preventiva. Para terminar se complementara en un apéndice de toda la información referente a la industria en cuestión

Transferable Classical Force Field for Pure and Mixed Metal Halide Perovskites Parameterized from First-Principles

Identificador de proyecto: PCI2019-111839-2 (SCALEUP)Many key features in photovoltaic perovskites occur in relatively long time scales and involve mixed compositions. This requires realistic but also numerically simple models. In this work we present a transferable classical force field to describe the mixed hybrid perovskite MAxFA1¿xPb(BryI1¿y)3 for variable composition (¿x, y ¿ [0, 1]). The model includes Lennard-Jones and Buckingham potentials to describe the interactions between the atoms of the inorganic lattice and the organic molecule, and the AMBER model to describe intramolecular atomic interactions. Most of the parameters of the force field have been obtained by means of a genetic algorithm previously developed to parametrize the CsPb(BrxI1¿x)3 perovskite (Balestra et al. J. Mater. Chem. A. 2020, DOI: 10.1039/d0ta03200j). The algorithm finds the best parameter set that simultaneously fits the DFT energies obtained for several crystalline structures with moderate degrees of distortion with respect to the equilibrium configuration. The resulting model reproduces correctly the XRD patterns, the expansion of the lattice upon I/Br substitution, and the thermal expansion coefficients. We use the model to run classical molecular dynamics simulations with up to 8600 atoms and simulation times of up to 40 ns. From the simulations we have extracted the ion diffusion coefficient of the pure and mixed perovskites, presenting for the first time these values obtained by a fully dynamical method using a transferable model fitted to first-principles calculations. The values here reported can be considered as the theoretical upper limit, that is, without grain boundaries or other defects, for ion migration dynamics induced by halide vacancies in photovoltaic perovskite devices under operational conditions.TU/