A Model for Isotropic Crystal Growth from Vapor on a Patterned Substrate

We developed a consistent mathematical model for isotropic crystal growth on a substrate covered by the mask material with a periodic series of parallel long trenches where the substrate is exposed to the vapor phase. Surface diffusion and the flux of particles from vapor are assumed to be the main mechanisms of growth. A geometrical approach to the motion of crystal surface in two dimensions is adopted and nonlinear evolution equations are solved by a finite-difference method. The model allows the direct computation of the crystal surface shape, as well as the study of the effects due to mask regions of effectively nonzero thickness. As in experiments, lateral overgrowth of crystal onto the mask and enhanced growth in the region near the contact of the crystal and the mask is found, as well as the comparable crystal shapes. The growth rates in vertical and lateral directions are investigated.Comment: 21 pages; submitted to the Journal of Crystal Growt

The Developing Effects of Potassium Ferricyanide on Tetrahymena

Potassium Cyanide is a highly toxic chemical asphyxiant that interferes with the body\u27s ability to use oxygen, typically by directly affecting the body by ingestion, inhalation, skin contact, or eye contact(CDC, 2011). Due to its high toxicity, the main effect that leads to the downfall of the organism begins with the cessation of aerobic metabolism; it does this by cyanide binding to the ferric ions and inhibiting cytochrome oxidase within the mitochondria (Zhang, 2015). There are no physical dangers the substance causes. Although, there are many chemical dangers. If used at temperatures higher than 70℉ The substance may produce toxic gasses such as hydrogen cyanide that create toxic hazards. Due to its toxic nature, a variability of temperature was not a good idea for our project considering it would be toxic for us and predictably kill all the Tetrahymena(Ware, 2020). Which is a reason we decided to use it when testing phagocytosis. My partner and I first decided on using potassium cyanide because of the research we found showing oxygen defects in uni- and multicellular organisms(Pham, 2007). Although there was one major issue, the compound was so toxic it would have killed our organisms prior to experimentation. Our resolution was finding a less toxic compound and potassium ferricyanide was that compound(Ware, 2020).. Using a compound lower in toxicity would allow us to create an experiment where we could test our hypothesis and test it at different ranges we had set for our project. The three factors we were testing are all related to cellular respiration, their ability to phagocytose is directly related to respiration, so therefore a good method to experiment on further( Skriver, 2009).Those ranges were testing how Tetrahymena would tolerate the compound. Knowing that potassium ferricyanide inhibits cellular respiration, which would cause a cascade effect on Tetrahymena in terms of their viability, motility, and ability to phagocytose. For our experiment, our goal was to find any change in the rate of phagocytosis, cell motility, and cell viability at different concentrations of potassium ferricyanide. It is vital since all of these factors require respiration to function properly. It will allow us to find out how each factor will affect the Tetrahymena. If future experimentations occurred, an insightful factor to add would be to test how all these factors affected the lifespan of Tetrahymena if treated with microdoses in comparison to those not treated with the drug

Time kink: modeling change of metric signature

The model of a signature change of a metric from the Lorenztian to Euclidean one with the use of a time dependent kink as $g_{00}$ component of the metric is considered. The metric which describes the continuous change of the signature of this type on a hypersurface is constructed and corresponding Einstein equations are solved in both regions of the space-time. The discontinuities of the Einstein tensor components on the hypersurface are discussed as well as junction conditions for the parameters of the solutions. Additionally, the properties of simple cosmological model are discussed in the model, the presence of an inflation in the model is demonstrated as a consequence of the signature change without any additional fields need. The possible appearance of this type of solution for the metric in the form of the scalar field in the framework of the Einstein-Cartan gravity is described. The Lagrangian for that field and it's properties are obtained as well as a time dependent potential of the field which separate the Lorentzian and Euclidean regions of the space-time

Harvard Crimson interviews Vinay Harpalani: Justice Department Drops Yale Admissions Lawsuit, Signifying Likely Shift in Harvard Suit

The Department of Justice on Wednesday dropped a lawsuit against Yale alleging discrimination in its admissions practices. Experts said it indicated the DOJ will likely withdraw support for a similar suit against Harvard. Vinay Harpalani, a law professor at the University of New Mexico, said he thinks such a move would make it “slightly less likely” that the court will hear the case, “if anything.” “It’s sending a bit of a message that the Biden administration’s DOJ is on the side of affirmative action, they’re on the side of Harvard, they’re going to help make these arguments. And the political winds have gone that way a little bit,” he said. Harpalani, the UNM professor, said he expects the DOJ to file a brief in support of Harvard should the Supreme Court take up the case

Fundamentos para el diseño de un modelo teórico de eficacia escolar desde un enfoque de la educación popular

The following reflection article presents an approach to the analysis of the theoretical foundations that allow the construction of a model of school effectiveness from a popular education approach carried out through a documentary research, based on the interpretive paradigm and the Hermeneutical method- I criticize, proposing a conceptual scheme built to address the five dimensions that underlie the investigative exercise and that, for the purposes of this research, are used to theoretically support a popular education approach; proposing the development of a sixth dimension, not contemplated in the five-dimensional model, but of great importance given the connotation of the investigated subject, the pedagogical dimension.El siguiente artículo de reflexión presenta una aproximación al análisis de los fundamentos teóricos que posibilitan la construcción de un modelo de eficacia escolar desde un enfoque de educación popular realizada a través de una investigación de carácter documental, basada en el paradigma interpretativo y el método  Hermenéutico-critico, planteándose  un esquema conceptual construido para abordar las cinco dimensiones que subyacen al ejercicio investigativo y que, para efectos de la presente investigación, se utilizan para fundamentar teóricamente un enfoque de educación popular; proponiendo el desarrollo de una sexta dimensión, no contemplada en el modelo pentadimensional, pero sí de gran importancia dada la connotación de la temática investigada, la dimensión pedagógica.   ABSTRACT The following reflection article presents an approach to the analysis of the theoretical foundations that allow the construction of a model of school effectiveness from a popular education approach carried out through a documentary research, based on the interpretive paradigm and the Hermeneutical method- I criticize, proposing a conceptual scheme built to address the five dimensions that underlie the investigative exercise and that, for the purposes of this research, are used to theoretically support a popular education approach; proposing the development of a sixth dimension, not contemplated in the five-dimensional model, but of great importance given the connotation of the investigated subject, the pedagogical dimension.  Key Words: School Efficacy, Efficacy Models, Popular Education    RÉSUMÉ L'article de réflexion suivant présente une approche de l'analyse des fondements théoriques qui permettent la construction d'un modèle d'efficacité scolaire à partir d'une approche d'éducation populaire réalisée à travers une recherche documentaire, basée sur le paradigme interprétatif et la méthode herméneutique- Je critique, proposant un schéma conceptuel construit pour aborder les cinq dimensions qui sous-tendent l'exercice d'enquête et qui, aux fins de cette recherche, sont utilisées pour soutenir théoriquement une approche d'éducation populaire ; proposant le développement d'une sixième dimension, non envisagée dans le modèle à cinq dimensions, mais d'une grande importance compte tenu de la connotation du sujet étudié, la dimension pédagogique. Mots-Clés: Efficacité des écoles, modèles d'efficacité, éducation populair

Análisis del sector turístico de la ciudad de Barranquilla aplicando técnicas de aprendizaje automático

Introduction: Annually more than 6.5 million people arrive in Colombia from other countries, as indicated by the Ministry ofCommerce, Industry and Tourism, demonstrating that the country is a key tourist destination in the region. It should take advantage of the boom in the sector and enter the market as an innovative, diverse and high-value destination.Objective: The objective of this research is to present in a general way the tourism sector in Colombia and to introduce theconcept of machine learning applied to this sector.Methodology: For the documentation of this study, a methodology of exploration of secondary sources was used, through theexploration of databases such as Scopus, Science Direct, EbscoHost, IEEE, among others.Results: In the conceptual review, it was found that Colombia has great tourism potential in different areas and in its variousregions. However, there are limitations in the management and organization of the sectors and in the implementation of newtechnologies to improve their competitiveness.Conclusion: The tourism sector seeks more realistic and satisfactory solutions because of ICT innovation and the use of computer systems and telecommunications equipment in information processing, which allows better responses to customers andimprove production systems.Introducción: Anualmente llegan a Colombia más de 6.5 millones de personas provenientes de otros países, según lo indicado por el Ministerio de Comercio, Industria y Turismo, demostrando que el país es un  destino turístico clave en la región. Se debe aprovechar el auge que vive el sector e insertarse en el mercado como un destino innovador, diverso y de alto valor.Objetivo: El objetivo de esta investigación es presentar de manera general el sector turístico en Colombia e introducir elconcepto de aprendizaje automático aplicado a dicho sector.Metodología: Para la documentación de este estudio, se utilizó una metodología de exploración de fuentes secundarias, a través de la exploración de bases de datos como Scopus, Science Direct, EbscoHost, IEEE, entre otras.Resultado: En la revisión conceptual se encontró que Colombia tiene un gran potencial turístico en diferentes áreas y en sus diversas regiones. Sin embargo, existen limitaciones en la gestión y organización de los sectores y en la implementación denuevas tecnologías para mejorar su competitividad.Conclusión: El sector turístico busca soluciones más realistas y satisfactorias como resultado de la innovación de las TIC y el uso de sistemas informáticos y equipos de telecomunicaciones en el procesamiento de la información lo que permite dar mejores respuestas a los clientes y mejorar los sistemas productivos

Caracterización de los niveles de convivencia, clima escolar y causas de conflicto en los estudiantes de la I.E. Fermín Tilano

Maestría en EducaciónThis investigation’s objective was to establish the perception of the scholar environment, the causes of the conflict and the convivence levels between the students of the Educational Institution “Fermín Tilano” from the village of Chorrera, Atlantico. This research is non-experimental quantitative, transversal and descriptive as it explores the impact of modalities, categories or levels of one or more variables in a population, meaning that they are purely descriptive studies. This is a non experimental work because no variable is deliberately manipulated. In contrary, the perceptions of the students associated with the school life such as the environment, its characteristics, and negative manifestations were measured. To achieve this end, an adaptation of the questionnaire for students, teachers and families about school convivence was conducted, taken from the book School Violence by Rosario Ortega and Rosario Del Rey (2003). The results shows that a good scholar climate is perceived (55% of students get along with their peers and 91.7 % of teachers think that little or no clashes occur with students). The majority of the students (95%) believe that the teachers have a good opinion about them. 82.5% of students have a normal or good opinion of their peers. Regarding integration, 87.5% of students believe they are integrated. 87.5% of the alumni believe that teachers do intervene in situations of school conflict. The majority of the students (80%) consider that the parents, teachers and students must be the ones who solve the conflicts and situations of bad behaviour within the educational institution.La presente investigación tuvo como objetivo establecer la percepción del clima escolar, las causas de conflicto y los niveles de convivencia dentro de los estudiantes de la Institución Educativa Fermín Tilano del Corregimiento de Chorrera – Atlántico. Esta investigación es de tipo cuantitativo no experimental, transversal y descriptiva, ya que indaga la incidencia de las modalidades, categorías o niveles de una o más variables en una población, es decir, son estudios netamente descriptivos. Este trabajo no es experimental debido a que no se manipulan deliberadamente las variables. De forma contraria, se midieron las percepciones de los estudiantes, asociadas a la convivencia escolar como lo son el ambiente, sus características y manifestaciones negativas. Para lograr tal fin se hizo la adaptación del cuestionario para estudiantes, docentes y para familias sobre la convivencia escolar de Ortega, R.; Del Rey, R. (2003). Los resultados indican que se percibe un clima escolar bueno (El 55% de los estudiantes se llevan bien con sus compañeros y el 91,7% de los docentes considera que poco o nada se presentan enfrentamientos con sus alumnos). La mayoría de los estudiantes (95%) creen que los profesores tienen buena opinión de ellos. El 82,5 % tienen una opinión normal o buena de sus compañeros. Con respecto a la integración, el 87,5% de los alumnos consideran que están integrados. El 87,5% de los alumnos cree que los docentes si atienden las situaciones de conflicto escolar. La gran mayoría de los alumnos (80%) considera que los padres de familia, los profesores y estudiantes deben ser los encargados de resolver los conflictos y situaciones de mala convivencia en la institución educativa

Framework de gobierno y gestión de la innovación TI en instituciones de educación superior

Este trabajo se apoya en los estándares de gobierno y gestión de Tecnología Informática para proponer un framework que permita llevar a cabo el gobierno y gestión de la innovación TI acorde a las necesidades de las instituciones de educación superior, y mostrando su aplicabilidad mediante la implementación de un modelo de madurez en la Universidad del Norte.MaestríaMagister en Gobierno de Tecnología Informátic

Estrategia de integración de proveedores para una empresa ensambladora de automóviles en Colombia

96 Páginas.Las grandes industrias automotrices como las de Estados Unidos, Corea, China y México, son las amenazas a las que se tiene que enfrentar la industria automotriz colombiana. Si se analizan detalladamente todos los sectores involucrados en los distintos TLC suscritos, se puede considerar que aunque la gran mayoría enfrenta grandes retos para ser competitivos, no solo para exportar sino inclusive para sostenerse en el mercado nacional, el más amenazado es precisamente el sector automotriz. Por lo anterior, es importante realizar una reestructuración en las estrategias de operación de las ensambladoras nacionales. Para el caso específico de esta investigación se tomó como base una de las empresas ensambladoras en Colombia con el fin de identificar la importancia de reducir sus costos frente a las marcas importadas como Hyundai, Kia y Volkswagen principalmente. Teniendo en cuenta los factores anteriores, en este trabajo de investigación se realizó la estrategia de suministro “SISCAI” (suppliers integration strategy for Colombian automotive industry) que consiste en la combinación y configuración de características clave encontradas en las estrategias seleccionadas por el proceso analítico jerárquico, adaptándola a las condiciones requeridas para operar en Colombia y a las de cada proveedor o ensambladora. Con la aplicación de “SISCAI” se pudo comprobar la obtención de resultados positivos como: reducción de inventarios de material ckd y local, tiempos de entrega, flexibilidad en la producción, calidad del producto final, cuellos de botella, mano de obra directa, rechazos por mala manipulación de materiales principalmente