Análisis de los asentamientos generados en el suelo subyacente al edificio A4 del Tecnológico de Costa Rica

Proyecto de Graduación (Licenciatura en Ingeniería en Construcción) Instituto Tecnológico de Costa Rica, Escuela de Ingeniería en Construcción, 2021La presente investigación estudia la interacción suelo estructura mediante la recopilación de muestras de campo en el suelo subyacente al Edificio A4 del Tecnológico de Costa Rica debido al agrietamiento que presentan los muros del segundo nivel de la edificación y según la información investigada, su comportamiento puede ocurrir debido a la existencia de asentamientos diferenciales. Primeramente, se han obtenido muestras de campo mediante el ensayo SPT -proyección de la capacidad admisible del suelo por estratigrafía- y extracción de núcleos inalterados para procesarlos mediante pruebas de laboratorio, tales como: Granulometría con 57.1% del material pasando el tamiz 200, Contenido de Humedad al 40.76 %, Límites de Atterberg que nos permite por medio de la carta de plasticidad y la clasificación SUCS caracterizar el suelo y finalmente, la Consolidación Unidimensional. Unido a esto, la carta de plasticidad indica la presencia de arcillas/limos de alta plasticidad y un potencial expansivo alto. Con ayuda del ensayo de Consolidación se observa una consolidación de 2.194 mm de una probeta de 19.999 mm para una carga de 8 kg. El objetivo de realizar estos procesos es identificar la presencia de suelos con algún grado de expansión, conocer la relación de vacíos del suelo, carga de preconsolidación y coeficientes de consolidación. Partiendo del objetivo general de la investigación, con ayuda del software SAP 2000 se realiza un modelo, basándose en las dimensiones reales de la edificación la cual estará sometida a cargas gravitacionales transmitidas a la cimentación. Estas cargas son contrarrestadas por esfuerzos del suelo, donde se permiten desplazamientos en los apoyos de la estructura. Los desplazamientos son determinados por medio de iteraciones, con el fin conocer cuál es el desplazamiento (asentamiento) que debe suceder, para aproximarse al momento de agrietamiento de las vigas. Considerando lo anterior, los ensayos demuestran que los suelos expansivos por su naturaleza generan algún tipo de esfuerzo -asentamientos- capaz de afectar la edificación tanto la condición estructural, como la condición de servicio. Finalmente, se proponen soluciones para contrarrestar los efectos de los asentamientos desde el punto de vista geotécnico y estructural.This research studies the floor-structure interaction through the collection of field samples in the underlying soil to Building A4 at Tecnológico de Costa Rica due to cracking appearances on the second floor of the building and according to the information investigated, this behavior is possibly to the existence of differential settlements. Firstly, field samples have been obtained through the SPT test -projection of the allowable capacity of the soil by stratigraphy- and extraction of unaltered blocks for processing through laboratory testing such as: Granulometry, with 57.1% of the material passing the 200 mesh, Humidity Content (40.76 %), Atterberg Limits which allows us through the plasticity card and SUCS to characterize the soil and finally, Unidimensional Consolidation test. Jointly, the plasticity card indicated the presence of clays/slimes with high plasticity and high potential for expansion. With help from the Consolidation test, settlements of 2.194 mm are observed for a sample of 19.999 mm in length, with an 8 kg load applied. The goal of carrying out these processes is to identify the presence of soils with some grade of expansion, know the relationship of voids in the ground as well as settlements, preconsolidation load and consolidation coefficients. Starting off the specific objectives of the investigation, it is modeled a wall with help from SAP2000 software to determine the behavior of the soil pressures, based on the real dimensions of the building and which will be subject to various gravitational loads, transmitted through to the foundations. These loads are counterbalanced by efforts from the soil, where displacements are allowed in the supports of the structure. The displacements are determined through iterations, in order to know which is the displacement (settlement) that must happens to approach the cracking moment of the beams. Considering the above, results are obtained through the tests performed which demonstrate that the settlements generate efforts -settlement- capable of significantly impacting the structural and service conditions. Finally, solutions are proposed to counteract the effects of the settlements from a geotechnical and structural standpoint

Diseño de pasos para peces en barraje, para disminuir la pérdida de ictiofauna en el río Uquihua, Palmeras, Rioja – 2018

La presente investigación titulada “diseño de pasos para peces en barraje, para disminuir la pérdida de ictiofauna en el río Uquihua, Palmeras, Rioja – 2018”, está enmarcada en diferentes teorías relacionadas al diseño de pasos para peces, especialmente en la expuesta por el ingeniero civil Hugo Champutiz en su tesis de pre grado titulada “Bases de diseño de escaleras para peces”, de la cual se tomó las consideraciones para los cálculos de diseño de los pasos para peces; para el barraje, se tomó como referencia a autores como el ingeniero Alfredo Mansen Valderrama, del ingeniero Máximo Villón Bejar y del Manual: Criterios de diseños de obras hidráulicas para la formulación de proyectos hidráulicos multisectoriales y de afianzamiento hídrico –ANA. El tipo de investigación es aplicada, ya que busca generar nuevos conocimientos basados en criterios teóricos de diseño de obras hidráulicas y saneamiento; el diseño de investigación es experimental propiamente dicho ya que el estudio está diseñado para determinar el cumplimiento de la hipótesis, y el nivel de estudio es explicativo puesto que se utilizan conocimientos existentes para aplicarlos empíricamente, para conocer la realidad. La población está referida a las especies nativas existentes en el río Uquihua, y su población está conformada por dos especies que son la carachama y la mojara. Los instrumentos utilizados fueron: Ficha de registro de datos, guía de observación, herramientas manuales, equipos de laboratorio de suelos, equipos de topografía, softwares y libros de diseño de ingeniería. Por último, se llegó a la conclusión que el diseño es funcional y permite el paso de los peces, evitando su disminución por interferencia en su traslado en épocas de reproducción, ya que, de acuerdo a las consideraciones tomadas en cuenta para el diseño, las condiciones que se genera en cada paso son las adecuadas para garantizar el tránsito normal de los peces en cualquier época

La importancia del aprendizaje social y su papel en la evolución de la cultura

En este trabajo se presenta un análisis especulativo sobre la relación entre el aprendizaje social, la evolución y la cultura. Entendemos por especulativo el resultado de la reflexión procedente de un conocimiento teórico, pero sin haber sido sometida a la práctica. Se expone y analiza la información sobre el comportamiento de primates no humanos obtenida por diversos autores que apunta a considerar al aprendizaje social como una característica presente en algunas especies animales. Este hecho lleva a formular lapregunta: ¿Es posible que otras especies distintas a las humanas posean la capacidad de crear y reproducir cultura? Proponemos replantear el concepto de cultura como una interacción compleja entre mente-comportamiento que puede o no expresarse materialmente. Es probable que este tipo de cognición compleja haya aparecido muy temprano en la evolución animal, pero que en los seres humanos haya adquirido una dimensión distinta

Caracterización del sistema de producción avícola de traspatio en el Estado de Campeche, México.

A study was conducted to characterize the backyard chicken production system in Campeche State, Mexico, as the basis of a program for utilizing local poultry genetic resources. A total of 260 surveys were administered in person. The parents undertake backyard production activities. Farmers have, on average, 0.20 ± 0.1 hectares for raising local chickens (LC). Flock size was 24.4 ± 1.3 birds per household. The number of egg/hen/year was 45.8 ± 1.6. Confined and semi-confined production systems are used. Farmers fed chickens with corn, whereas chicks were fed with commercial feed. During the rainy season, flu and diarrheal diseases are more frequently observed. Body size is the main trait for acquiring/selecting breeders within/outside the flock. Selection of eggs for incubation is based on size and freshness. Feed shortages, diseases, predators, and lack of technical assistance services were the major constraints for LC backyard production. In conclusion, backyard chicken production based on LC provides a readily available source of animal protein and cash income for households in Campeche State, Mexico.Se realizó un estudio con el objetivo de caracterizar la producción avícola de traspatio en el estado de Campeche, México, como el inicio de un programa para la utilización de los recursos genéticos avícolas locales. Se encuestó a un total de 260 productores. Las actividades productivas de traspatio las realizan los padres. Los productores destinan un promedio de 0.20 ± 0.1 hectáreas para la cría de pollos locales (PL). El tamaño de la parvada fue de 24.4 ± 1.3 aves por hogar. El número de huevos/gallina/año fue de 45.8 ± 1.6. Se utiliza tanto el sistema de producción en confinamiento como en semi-confinamiento. Las aves son alimentadas con maíz, excepto los pollitos, que son alimentados con alimento balanceado comercial. Durante la época de lluvias se observan con mayor frecuencia problemas de diarrea y enfermedades respiratorias. El peso corporal es la principal característica por la que las aves reproductoras son seleccionadas dentro y fuera de la parvada. Los huevos destinados a incubación son elegidos con base en su tamaño y el número de días transcurridos desde que son puestos. La producción avícola de traspatio tiene como principales limitantes la falta de alimento para los animales, las enfermedades, los depredadores y la falta de asistencia técnica. En conclusión, la producción avícola de traspatio, basada en animales locales, provee de una fuente fácilmente disponible de proteína de origen animal e ingresos económicos a los hogares del estado de Campeche, México

Comparison of two phenotypical methods to segregate resistant and susceptible lambs to parasitic nematodes

The objective of this study was to compare two segregation methods to select resistant and susceptible female Pelibuey lambs infected naturally with gastrointestinal nematodes (GINs) in relation to their haematological and immunological response. For 6 months, faeces and blood samples were taken fortnightly from 40 grazing 5-month-old female lambs. The lambs were classified according to two methods using faecal egg count (FEC) as a phenotypical trait. In the first (reference) method (M3SE, n = 22), resistant (RES) lambs had FEC lower than the mean – 3 standard errors, the susceptible (SUS) lambs levels higher than + 3 standard errors(n = 10) and the intermediate (INT) lambs (n = 8) were categorised by having FECs between the two values. The second method (QUM) divided the population, using quartiles, into resistant (RES; 25%), intermediate (INT; 50%), and susceptible (SUS; 25%) lambs. The agreement between both methods was estimated using the Kappa index. The packed cell volume (PCV), total plasma protein (TPP) and peripheral eosinophils (EOS) were determined for each group. Serum was used to evaluate the IgA levels. PCV and TPP values were higher (P<0.01) in the RES lambs (31.5 ± 3.4 and 6.16 ± 0.5 g/dL by QUM, respectively, and 31.5 ± 3.9 and 6.24 ± 0.49 g/dL by M3SE, respectively) than the SUS lambs (28.1 ± 4.7 and 5.94 ± 0.5 g/d, respectively, by both methods). The EOS and IgA values increased with age. M3SE and QUM were in moderate agreement (Kappa = 0.43). We concluded that the two segregation methods allowed for the identification of the same female SUS lambs, but a greater number of animals were categorised phenotypically as resistant using the M3SE method. PCV and TPP can help to identify phenotypically resistant animals

Perspectives on the methods of a large systematic mapping of maternal health interventions.

BACKGROUND: Mapping studies describe a broad body of literature, and differ from classical systematic reviews, which assess more narrowly-defined questions and evaluate the quality of the studies included in the review. While the steps involved in mapping studies have been described previously, a detailed qualitative account of the methodology could inform the design of future mapping studies. OBJECTIVES: Describe the perspectives of a large research team on the methods used and collaborative experiences in a study that mapped the literature published on maternal health interventions in low- and middle-income countries (2292 full text articles included, after screening 35,048 titles and abstracts in duplicate). METHODS: Fifteen members of the mapping team, drawn from eight countries, provided their experiences and perspectives of the study in response to a list of questions and probes. The responses were collated and analysed thematically following a grounded theory approach. RESULTS: The objectives of the mapping evolved over time, posing difficulties in ensuring a uniform understanding of the purpose of the mapping among the team members. Ambiguity of some study variables and modifications in data extraction codes were the main threats to the quality of data extraction. The desire for obtaining detailed information on a few topics needed to be weighed against the benefits of collecting more superficial data on a wider range of topics. Team members acquired skills in systematic review methodology and software, and a broad knowledge of maternal health literature. Participation in analysis and dissemination was lower than during the screening of articles for eligibility and data coding. Though all respondents believed the workload involved was high, study outputs were viewed as novel and important contributions to evidence. Overall, most believed there was a favourable balance between the amount of work done and the project's outputs. CONCLUSIONS: A large mapping of literature is feasible with a committed team aiming to build their research capacity, and with a limited, simplified set of data extraction codes. In the team's view, the balance between the time spent on the review, and the outputs and skills acquired was favourable. Assessments of the value of a mapping need, however, to take into account the limitations inherent in such exercises, especially the exclusion of grey literature and of assessments of the quality of the studies identified

Mapping of research on maternal health interventions in low- and middle-income countries: a review of 2292 publications between 2000 and 2012.

BACKGROUND: Progress in achieving maternal health goals and the rates of reductions in deaths from individual conditions have varied over time and across countries. Assessing whether research priorities in maternal health align with the main causes of mortality, and those factors responsible for inequitable health outcomes, such as health system performance, may help direct future research. The study thus investigated whether the research done in low- and middle-income countries (LMICs) matched the principal causes of maternal deaths in these settings. METHODS: Systematic mapping was done of maternal health interventional research in LMICs from 2000 to 2012. Articles were included on health systems strengthening, health promotion; and on five tracer conditions (haemorrhage, hypertension, malaria, HIV and other sexually transmitted infections (STIs)). Following review of 35,078 titles and abstracts in duplicate, data were extracted from 2292 full-text publications. RESULTS: Over time, the number of publications rose several-fold, especially in 2004-2007, and the range of methods used broadened considerably. More than half the studies were done in sub-Saharan Africa (55.4 %), mostly addressing HIV and malaria. This region had low numbers of publications per hypertension and haemorrhage deaths, though South Asia had even fewer. The proportion of studies set in East Asia Pacific dropped steadily over the period, and in Latin America from 2008 to 2012. By 2008-2012, 39.1 % of articles included health systems components and 30.2 % health promotion. Only 5.4 % of studies assessed maternal STI interventions, diminishing with time. More than a third of haemorrhage research included health systems or health promotion components, double that of HIV research. CONCLUSION: Several mismatches were noted between research publications, and the burden and causes of maternal deaths. This is especially true for South Asia; haemorrhage and hypertension in sub-Saharan Africa; and for STIs worldwide. The large rise in research outputs and range of methods employed indicates a major expansion in the number of researchers and their skills. This bodes well for maternal health if variations in research priorities across settings and topics are corrected

Observation of the Crab Nebula with the HAWC Gamma-Ray Observatory

The Crab Nebula is the brightest TeV gamma-ray source in the sky and has been used for the past 25 years as a reference source in TeV astronomy, for calibration and verification of new TeV instruments. The High Altitude Water Cherenkov Observatory (HAWC), completed in early 2015, has been used to observe the Crab Nebula at high significance across nearly the full spectrum of energies to which HAWC is sensitive. HAWC is unique for its wide field-of-view, nearly 2 sr at any instant, and its high-energy reach, up to 100 TeV. HAWC's sensitivity improves with the gamma-ray energy. Above $\sim$1 TeV the sensitivity is driven by the best background rejection and angular resolution ever achieved for a wide-field ground array. We present a time-integrated analysis of the Crab using 507 live days of HAWC data from 2014 November to 2016 June. The spectrum of the Crab is fit to a function of the form $\phi(E) = \phi_0 (E/E_{0})^{-\alpha -\beta\cdot{\rm{ln}}(E/E_{0})}$. The data is well-fit with values of $\alpha=2.63\pm0.03$, $\beta=0.15\pm0.03$, and log$_{10}(\phi_0~{\rm{cm}^2}~{\rm{s}}~{\rm{TeV}})=-12.60\pm0.02$ when $E_{0}$ is fixed at 7 TeV and the fit applies between 1 and 37 TeV. Study of the systematic errors in this HAWC measurement is discussed and estimated to be $\pm$50\% in the photon flux between 1 and 37 TeV. Confirmation of the Crab flux serves to establish the HAWC instrument's sensitivity for surveys of the sky. The HAWC survey will exceed sensitivity of current-generation observatories and open a new view of 2/3 of the sky above 10 TeV.Comment: Submitted 2017/01/06 to the Astrophysical Journa