38 research outputs found

    Evaluación de diferentes tácticas para el control de gasterópodos (babosas terrestres) en el cultivo de lechuga (lactuca sativa l. Var. Fallgreen) en la zona de el guarco de Cartago

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    Tesis (Licenciatura en Ingeniería en Agronomía). Instituto Tecnológico de Costa Rica, Escuela de Agronomía,2014The terrestrial slugs are responsible for causing considerable economic losses on agricultural crops, some countries such as England, Thailand, United States, Colombia, Nicaragua, among others, report strong impacts on diverse crops. Nevertheless, its importance extends not only in these millionaire losses, but also for they act as intermediate vectors of the Angiostrongylus costaricensis nematodes, causing intestinal damages in the human being. Regarding to the previous information, it has promoted different investigations in the last years, with the aim of establishing efficient management tactics that allow to keep the populations below the economic threshold of damage. Within these tactics, they are synthetic substances as the metaldehyde and carbamates which are applied in different concentrations, shaped like pellets, same that by its characteristics in the short or medium term can have a repercussion on the biodiversity, so as an alternative to this tactic, the use of different types of traps around and within the plantations have generated reliable results. On the other hand, the use of botanical extracts of plant origin act on the behavior of this pest causing ,not only a repellent effect , but also a inedible reaction, so linked to the above, the use of agents of biological control such as the Phasmarhabditis hermaphrodita nematode, entomopathogenic microorganisms such as Pochonia chlamydosporia, and predators such as Scarites anthracinus y Pterostichus melanarius, have demonstrated a positive impact, not only in the management of terrestrial slugs, but also in the general equilibrium of the present populations in the crop, giving long-term benefits

    Aplicación de herramientas lean manufacturing para incrementar la productividad en el área de producción de la empresa Hunter Perú Sac, 2019

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    La presente investigación titulada: “Aplicación de herramientas lean manufacturing para incrementar la productividad en el área de producción de la empresa Hunter Perú Sac, 2019”, tuvo como objetivo determinar como la aplicación de la herramienta Lean Manufacturing impacta en el incremento de la productividad en el proceso de manufactura en el área de producción en la empresa HUNTER PERÚ SAC, 2019. Esto como respuesta al problema: ¿De qué manera la aplicación de herramientas de Lean Manufacturing incrementa la productividad en el área de producción en la empresa HUNTER PERÚ SAC, 2019? La presente investigación se desarrolló con un diseño pre experimental, con un enfoque cuantitativo, de esa forma la muestra fue conformada por 16 registros semanales de producción. Para optimizar la información solicitada, previamente se realizó la validación de los instrumentos y se evidencio la validez y confiabilidad, mediante la técnica de juicio de expertos; la técnica que se utilizó fueron las fichas de registro. Con referencia al objetivo general: Determinar como la aplicación de herramientas Lean Manufacturing incrementa la productividad en el área de producción en la empresa HUNTER PERÚ SAC, 2019, se definió que; hay una discrepancia significativa entre las medias de productividad antes y productividad después, luego de utilizar las herramientas 5s y Kaizen. Por ende, se llegó a la conclusión de hay un impacto entre el Lean Manufacturing y la productividad en la empresa HUNTER PERÚ SAC

    A real use case of semi-supervised learning for mammogram classification in a local clinic of Costa Rica

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The implementation of deep learning-based computer-aided diagnosis systems for the classification of mammogram images can help in improving the accuracy, reliability, and cost of diagnosing patients. However, training a deep learning model requires a considerable amount of labelled images, which can be expensive to obtain as time and effort from clinical practitioners are required. To address this, a number of publicly available datasets have been built with data from different hospitals and clinics, which can be used to pre-train the model. However, using models trained on these datasets for later transfer learning and model fine-tuning with images sampled from a different hospital or clinic might result in lower performance. This is due to the distribution mismatch of the datasets, which include different patient populations and image acquisition protocols. In this work, a real-world scenario is evaluated where a novel target dataset sampled from a private Costa Rican clinic is used, with few labels and heavily imbalanced data. The use of two popular and publicly available datasets (INbreast and CBIS-DDSM) as source data, to train and test the models on the novel target dataset, is evaluated. A common approach to further improve the model’s performance under such small labelled target dataset setting is data augmentation. However, often cheaper unlabelled data is available from the target clinic. Therefore, semi-supervised deep learning, which leverages both labelled and unlabelled data, can be used in such conditions. In this work, we evaluate the semi-supervised deep learning approach known as MixMatch, to take advantage of unlabelled data from the target dataset, for whole mammogram image classification. We compare the usage of semi-supervised learning on its own, and combined with transfer learning (from a source mammogram dataset) with data augmentation, as also against regular supervised learning with transfer learning and data augmentation from source datasets. It is shown that the use of a semi-supervised deep learning combined with transfer learning and data augmentation can provide a meaningful advantage when using scarce labelled observations. Also, we found a strong influence of the source dataset, which suggests a more data-centric approach needed to tackle the challenge of scarcely labelled data. We used several different metrics to assess the performance gain of using semi-supervised learning, when dealing with very imbalanced test datasets (such as the G-mean and the F2-score), as mammogram datasets are often very imbalanced

    Improving uncertainty estimations for mammogram classification using semi-supervised learning

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Computer aided diagnosis for mammogram images have seen positive results through the usage of deep learning architectures. However, limited sample sizes for the target datasets might prevent the usage of a deep learning model under real world scenarios. The usage of unlabeled data to improve the accuracy of the model can be an approach to tackle the lack of target data. Moreover, important model attributes for the medical domain as model uncertainty might be improved through the usage of unlabeled data. Therefore, in this work we explore the impact of using unlabeled data through the implementation of a recent approach known as MixMatch, for mammogram images. We evaluate the improvement on accuracy and uncertainty of the model using popular and simple approaches to estimate uncertainty. For this aim, we propose the usage of the uncertainty balanced accuracy metric

    Concurso de cuento científico ¡Imagino la ciencia y te la cuento!

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    Este libro es una muestra del desarrollo del “Evento de Divulgación Tecnológica” EDT, denominado 2° Concurso de Cuento Científico ¡Imagino la Ciencia y te la Cuento!, donde se evidencia la apropiación de las habilidades lingüísticas, comunicativas y competencias lectoras, dentro de los lineamientos STEAM y habilidades para el siglo XXI; como resultado se obtiene la creatividad e imaginación de los niños de 16 instituciones educativas beneficiarias de la estrategia de Tecnoacademia Itinerante Boyacá, quienes, desde su perspectiva y diferentes vivencias, expresan el gusto por la lectura y la escritura, materializada en la construcción de cuentos que fueron leídos por un equipo de profesionales interdisciplinario y donde fueron seleccionados algunos cuentos y dibujos para esta publicación.El primer niño que fue a la luna -- El gran descubrimiento -- Hacia el futuro -- Un amor entre dos mundos -- La aventura de mis sueños -- La felicidad siempre nos espera -- Valiente valentina -- Un sueño perdido -- El científico loco -- El extraterrestre que quería vivir en la tierra -- El mejor líder -- Arkade un juego sin fin -- Experimento d-037 – Robotsing -- El viejo científico -- Fiesta en la luna -- El guardián del bosque -- 20 años de silencio -- Niveles de organización -- De los seres vivos -- Doña Lila y doña Justa -- Proyecto de inclusiòn -- Tecnoacademia “Pintando protejo la naturaleza”na123 página

    Conferencia internacional. Desafíos de la Investigación e innovación en tiempos de Covid-19

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    En 2018, Treinta y nueve estudiantes femeninas del X ciclo del periodo 2018-1 de la escuela de Psicología de una universidad particular del cono norte de Lima, ellas han descrito el romance de su personas cercanas a ellas. Se analizaron los 266 casos de parejas de enamorados estaban el rango de 17 a 25 años. El instrumento que se usó fue una CUESTIONARIO CUPIDO que es una escala nominal de conductas donde las estudiantes de psicología clasificaban los comportamientos en categorías preestablecidas, claramente definidas y mutuamente excluyentes. La conclusión más importante del estudio observacional fue que las parejas analizadas en un 64.4 % la mujer ero atrajo al varón y después el varón emo conectó con la mujer. También han observado otro estilo de romance cuando el varón ero atrajo a la mujer por su cuerpo atracción y después la mujer fue la que emo conectó con el varón y observaron este hecho en un 35.6 % de los casos

    7th Drug hypersensitivity meeting: part two

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    No abstract availabl

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Annual Conference on Formative Research on EFL. Practices thar inspire change.

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    The conference papers of the Annual Conference on Formative Research on EFL. Practices thar inspire change collect pedagogical experiences, research reports, and reflections about social issues, language teaching, teaching training, interculturality under the panorama of the Covid-19 pandemic. Each paper invites the reader to implement changes in their teaching practice through disruptive pedagogies, reflect on the social and emotional consequences of the lockdown, new paths for teacher training and different approaches for teaching interculturality. We expect to inspire new ways to train pre-service teachers and teach languages in this changing times
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