59 research outputs found

    Consideraciones acerca de la enseñanza y aprendizaje de las matemáticas

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    En este capítulo presentamos una perspectiva fundamentada desde la que entendemos que se debería interpretar una nueva propuesta curricular de las matemáticas de la enseñanza obligatoria. Muchas de las ideas que exponemos aquí no son nuevas; años de reformas curriculares y la propia investigación en educación matemática han puesto de relieve muchas de ellas, en muchos casos recogidas en las propuestas oficiales, pero la realidad de las aulas no permite verlas convertidas en acción. En el capítulo volvemos a ponerlas sobre la mesa, justificamos su necesidad, e intentamos reflexionar sobre los elementos que dificultan su puesta en marcha focalizando el papel de sus mediadores principales. Las preguntas clave que guían nuestra reflexión son qué deberían ser las matemáticas escolares y por qué hemos de enseñar matemáticas

    Radioinmunoanalisis simultaneo de cinco hormonas esteroidales

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    En este trabajo se describe un método para la determinación de androstendiona, progesterona.dihidi'otestosterona, testosterona y 17—hidroxi—progesterona en muestras de 1 ml de suero femenino y masculino. Después de la extracción de los esteroides la mezcla es sometida a cromatografía en una columna de Lipidex—5000 (hidroxialcoxipropil Sephadex) en n— hexano: cloroformo 95:5. La evaluación final de los diferentes esteroides se hace por medio de radioinmunoanálisis específicos usando carbón—dextrano [jara separar las fracciones libre y ligada de la radioactividad. Los cinco compuestos se resolvieron en cuatro fracciones eluyendo conjuntamenteandrostendiona y progesterona, las cuales fueron determinadas específicamente usando antisueros selectivos. La recuperación varió entre 63.5 y 93.7% siendo los valores más bajos para dihidrotestosterona. La interferencia o blanco para los cinco esteroides fue inferior al límite de detección de los radioinmunoanálisis (10 pg) y la exactitud, usando el criterio de la prueba de pureza radioquímica,fue comprobada para los análisis de progesterona y testosterona. En un estudio comparativo se analizaron las cinco hormonas en un grupo de hombres y mujeres normales mediante la determinación directa del extracto y después de la etapa cromatográfica. En la mayoría de los casos se encontrarondiferencias significativas entre los promedios de uno y otro método y solo en uno de ellos (17—hidroxiprogesterona en suero masculino) no hubo diferencia. Se establecieron los niveles de estos esteroides en suero femenino en las fases folicular y luteal del ciclo menstrual y en algunos de ellos se estudió la variación circadiana. Dichos niveles también se determinaron después de practicar pruebasde estímulo y/o de freno para su secreción, en muestras provenientes de pacientes con sospecha de alteración relacionada con el hirsutismo

    Implementación de la estrategia CuidArte del Ministerio de Educación Nacional, sobre hábitos de vida saludables en el jardín infantil pintando sueños de la localidad de Kennedy, Bogotá D.C.

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    Formatos de encuestas, tabulacion y resultados.Durante el desarrollo del proyecto planteado se presenta una propuesta de implementación de la estrategia CuidArte, enfocada a los hábitos de vida saludable en niños y niñas de 1 a 4 años en el “Jardín Pintando Sueños”. La presente propuesta se desarrolla utilizando los lineamientos de la metodología general ajustada (MGA) y estándares establecidos para la gestión de proyectos. Igualmente, el proyecto se enmarca en la línea de investigación de profundización del programa de la UNAD de la Dinámica Organizacional, en la Sublínea Gestión de procesos organizacionales. La propuesta está enfocada para generar hábitos de vida saludable y ayudar a los padres en la crianza; así mismo incentivar una orientación nutricional para crear hábitos de vida saludables tanto para las familias, como para los jardines infantiles que tengan niños y niñas en edades de 1 a 4 años, comunidad objetivo de la propuesta del proyecto de grado. De igual modo, garantizar la apropiación de saberes y conocimientos que contribuyan al crecimiento, desarrollo y aprendizaje de estos niños, familia y comunidades educativas como los jardines infantiles.During the development of the proposed project, a proposal for the implementation of the strategy of healthy life habits in boys and girls from 1 to 4 years of age is presented in the “Jardin Pintado Sueños”. This proposal is developed using the guidelines of the adjusted general methodology (AMS) and the parameters established for project management. Likewise, the project is part of the line of research to deepen the UNAD program on Organizational Dynamics, in the Subline of Organizational Processes Management. The proposal is focused to generate healthy lifestyle habits and help parents in parenting; Likewise, encourage nutritional orientation to create healthy lifestyle habits for both families and kindergartens that have boys and girls between the ages of 1 and 4, the target community for the proposed degree project. Anyway, guarantee the appropriation of knowledge and knowledge that contribute to the growth, development and learning of these children, families and educational communities such as kindergartens

    Association between emergency department length of stay and adverse perioperative outcomes in emergency surgery: A cohort study in two Colombian University hospitals

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    Background: In low- and middle-income countries emergency surgery represents a higher proportion of the total number of surgeries and is associated with greater morbidity/mortality. Study aims were to determine if emergency department length of stay (ED-LOS) was associated with adverse perioperative outcomes and if such association varied across patient's risk categories. Methods: A retrospective cohort study was conducted of adult patients who underwent orthopedic or abdominal emergency surgery at two Colombian University hospitals. The population comprised a mix of a representative sample of eligible cases, with unselected patients (2/3), enriched with a high-risk subset (1/3). ED-LOS was defined as the interval between emergency department arrival and surgery start time. Our primary outcome was an adverse perioperative outcome during hospitalization, which was a composite of in-hospital mortality or severe complications such as major cardiovascular adverse events, infection, renal failure and bleeding. Results: Among 1487 patients analyzed, there were 519 adverse perioperative outcomes including 150 deaths. In the unselected sample (n = 998) 17.9% of patients presented an adverse perioperative outcome with a mortality of 4.9%. The median ED-LOS was 24.6 (IQR 12.5-53.2) hours. ED-LOS was associated with age, comorbidities and known risk factors for 30-day mortality. Patients developing an adverse perioperative outcome started surgery 27.1 h later than their counterparts. Prolonged ED-LOS increased the risk of an adverse perioperative outcome in patients without risk factors (covariate-adjusted OR = 2.52), while having 1-2 or 3+ risk factors was negatively associated (OR = 0.87 and 0.72, respectively, p less than 0.001 for the interaction). Conclusion: Prolonged ED-LOS is associated with increased adverse perioperative outcome for patients without risk factors for mortality, but seems protective and medically justified for more complex cases. © 2019 The Author(s)

    Ethics Of English On Business Presentation

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    Business presentation is needed by persons to inform or persuade audience about certain topics. Through the presentation, information are clearly received by audience. So it needs many aspects to do, such as chronological order of presentation; clear language; good attitude and behavior; and polite ethics. Ethics is the standards one uses to determine right from wrong in terms of thought and behavior. It is one of major components of successful presentation. To do that, ones could adopt ethics from their own culture or culture where they are right now, i.e. in abroad. This paper here intends to show ethic of English business presentation and ethic of presentation to public in order to persuade audience to use the product/ program. It means that it is not to use on presentation of national or International seminar because the rule is not so detailed and complicated The business presentation based on the result of research and good communication is necessary to present objective information, therefore public will get clear and objective understanding. In fact, showing strengths on the own products and showing the weaknesses of others are prohibited to save the existence of brands

    Microstructural and Mechanical Characteristics of Alkali-Activated Binders Composed of Milled Fly Ash and Granulated Blast Furnace Slag with µ-Limestone Addition

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    Concrete is the most used construction material, needing large quantities of Portland cement. Unfortunately, Ordinary Portland Cement production is one of the main generators of CO2, which pollutes the atmosphere. Today, geopolymers are an emerging building material generated by the chemical activity of inorganic molecules without the Portland Cement addition. The most common alternative cementitious agents used in the cement industry are blast-furnace slag and fly ash. In the present work, the effect of 5 wt.% µ-limestone in mixtures of granulated blast-furnace slag and fly ash activated with sodium hydroxide (NaOH) at different concentrations was studied to evaluate the physical properties in the fresh and hardened states. The effect of µ-limestone was explored through XRD, SEM-EDS, atomic absorption, etc. The addition of µ-limestone increased the compressive strength reported values from 20 to 45 MPa at 28 days. It was found by atomic absorption that the CaCO3 of the µ-limestone dissolved in NaOH, precipitating Ca(OH)2 as the reaction product. SEM-EDS analysis showed a chemical interaction between C-A-S-H- and N-A-S-H-type gels with Ca(OH)2, forming (N, C)A-S-H- and C-(N)-A-S-H-type gels, improving mechanical performance and microstructural properties. The addition of µ-limestone appeared like a promising and cheap alternative for enhancing the properties of low-molarity alkaline cement since it helped exceed the 20 MPa strength recommended by current regulations for conventional cement

    Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores

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    Funder: Funder: Fundación bancaria ‘La Caixa’ Number: LCF/PR/PR16/51110003 Funder: Grifols SA Number: LCF/PR/PR16/51110003 Funder: European Union/EFPIA Innovative Medicines Initiative Joint Number: 115975 Funder: JPco-fuND FP-829-029 Number: 733051061Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease

    New insights into the genetic etiology of Alzheimer's disease and related dementias

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    Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
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