Evaluation of RT-PCR and hemi-nested RT-PCR in brain samples from dogs with neurologic signs compatible with distemper

Foi comparado o valor diagnóstico das técnicas de RT-PCR e heminested RT-PCR (hnRT-PCR) em amostras de cérebro de cães com sintomatologia nervosa compatível com cinomose. Fragmentos do sistema nervoso central (SNC) colhidos de 68 animais foram testados pela Imunofluorescência direta (IFD) e, independentemente do resultado, foram armazenados a -20°C por pelo menos três anos. Após esse período, foram submetidos a RT-PCR e a hnRT-PCR com oligonucleotídeos iniciadores direcionados ao gene codificador da nucleoproteína N. As proporções de resultados positivos/examinados foram: 59/68 para a IFD, 40/68 para a RT-PCR (Kappa = 0,358) e 54/68 quando associada à heminested PCR (Kappa = 0,740). Houve nove resultados negativos nas três técnicas empregadas. Os resultados do coeficiente Kappa entre a IFD e hnRT-PCR demonstram que apesar das condições de armazenamento, a hnRT-PCR pode ser utilizada em estudos retrospectivos.The diagnostic value of RT-PCR and hemi-nested RT-PCR (hnRT-PCR) was compared in brain samples of dogs presenting neurological signs compatible with canine distemper. Samples of central nervous system (CNS) were collected from 68 dogs and tested by direct immunofluorescence test (RFID) and, independent of the results, they were stored at -20°C for at least three years. They were submitted to the RT-PCR and hnRT-PCR techniques aiming to determine the gene responsible for the viral nucleoprotein decoding. Fifty-nine samples were positive for RIFD, 40 for RT-PCR (Kappa = 0.358) and 54 for hnRT-PCR (Kappa = 0.740). All nine RIFD negative samples were also negative for RT-PCR and hnRT-PCR. In spite of the storage duration and proper sample conditions, the estimated accordance between hnRT-PCR and RIFD demonstrated that hnRT-PCR technique can be applied in retrospective studies

“Un minuto para matemáticas”. Una experiencia de diversión, aprendizaje y divulgación al explorar patrones numéricos

El presente texto muestra una experiencia de divulgación de las matemáticas a través de la exploración de patrones numéricos con material concreto; se fundamenta en las bondades del juego (De Guzmán, 2007) y en el empleo del razonamiento inductivo en la construcción de generalizaciones (Osorio, 2012; Cañadas, Castro y Castro, 2008). Los resultados revelan el empleo de estrategias en la búsqueda de patrones, trabajo colaborativo y motivación hacia las matemáticas. Se concluye que la propuesta es un valioso escenario para las tareas de generalización y la divulgación de la ciencia

A comparison of machine learning methods for extremely unbalanced industrial quality data

The Industry 4.0 revolution is impacting manufacturing companies, which need to adopt more data intelligence processes in order to compete in the markets they operate. In particular, quality control is a key manufacturing process that has been addressed by Machine Learning (ML), aiming to improve productivity (e.g., reduce costs). However, modern industries produce a tiny portion of defective products, which results in extremely unbalanced datasets. In this paper, we analyze recent big data collected from a major automotive assembly manufacturer and related with the quality of eight products. The eight datasets in- clude millions of records but only a tiny percentage of failures (less than 0.07%). To handle such datasets, we perform a two-stage ML comparison study. Firstly, we consider two products and explore four ML algorithms, Random Forest (RF), two Automated ML (AutoML) methods and a deep Autoencoder (AE), and three balancing training strategies, namely None, Synthetic Minority Oversampling Technique (SMOTE) and Gaussian Copula (GC). When considering both classification performance and computational effort, interesting results were obtained by RF. Then, the selected RF was further explored by considering all eight datasets and five balancing methods: None, SMOTE, GC, Random Undersampling (RU) and Tomek Links (TL). Overall, competitive results were achieved by the combination of GC with RF.This work is supported by: European Structural and Investment Funds in the FEDER component, through the Operational Competitiveness and Internation- alization Programme (COMPETE 2020) [Project n 39479; Funding Reference: POCI-01-0247-FEDER-39479]

Historia, matemáticas y profesores en la UAN

Esta investigación es de carácter no experimental y tiene como propósito obtener elementos que permitan diagnosticar cuanto saben de la historia de las matemáticas los docentes de la asignatura en la Universidad Autónoma de Nayarit UAN. Su implementación obedece a la posibilidad que la historia brinda a los profesores de llevar a sus estudiantes al reconocimiento de la procedencia de los conceptos y propiedades de la disciplina, en procesos reales del universo y a la existencia de una sociedad (Hernández, 2004), así como en la necesidad docente de contar con herramientas que permitan desarrollar la dimensión epistémica propuesta por Godino, Bencomo, Font, & Wilhelmi, 2006. Dicha investigación se realizó con maestros de matemáticas del nivel superior de la UAN, se utilizó estadística descriptiva. Los resultados revelan que la mayoría de los docentes desconoce las etapas de la historia de las matemáticas, aportaciones y principales exponentes

Evaluación: ¿articulación entre la teoría y la práctica en la unidad de aprendizaje de lenguaje y pensamiento matemático?

Esta investigación es de carácter correlacional y tiene como propósito determinar el impacto en aula, de las prácticas evaluativas de los profesores de Lenguaje y Pensamiento Matemático de la Universidad Autónoma de Nayarit UAN tras participar en un taller sobre modalidades, técnicas y estrategias de evaluación constructivista en matemáticas. Su implementación obedece a la diagnóstica desarticulación entre la evaluación promovida en el modelo académico de la UAN y la que se realizaba en el aula (Cortez y Ponce, 2007), así como en el interés institucional de contribuir con el diseño de técnicas y procedimientos que permitan evaluar los aprendizajes y todos los procesos que existen detrás de ellos. Se utilizó estadística descriptiva y se determinó la asociación e independencia, además se analizaron las impresiones de los estudiantes. Los resultados revelan que existe evidencia considerable sobre la práctica en el aula de estrategias evaluativas constructivistas

Research Ethics Training of Trainers: Developing Capacity of Bolivian Health Science and Civil Society Leaders

Program/Project Purpose: The University of San Andres, Faculty of Medicine in La Paz, Bolivia in collaboration with Touro University California, Public Health Program was awarded a NIH Research Ethics Planning Grant in June, 2013 to develop strategies and processes for implementation of a comprehensive national research ethics program for Bolivia. Although the importance of scientific research based on ethical principles is highlighted in the Bolivian constitution and national health legislation, few Bolivian academics, researchers and health professionals have received formal training in the principles and practices of research ethics. A principle aim of the Planning Grant is to develop and implement a Research Ethics Train the Trainers (TOT) course with the goal of training faculty for future implementation of a national research ethics program. Structure/Method/Design: A Project Directors Committee representing public health science universities from four participating Bolivian Departments/States (La Paz; Santa Cruz, Cochabamba & Chuquisaca) was formed to oversee all project activities including implementation of a three day in-person TOT followed by a 10 week online training. Training modules utilized materials developed by Bolivian academics and scientists and international research ethics programs at PAHO (Pan American Health Organization) and CITI (Collaborative Institutional Training Initiative), University of Miami. TOT University and civil society representatives were selected from each participating Department/State for a total of 26 participants. Upon completion of the training, participants were asked to implement educational research ethics activities in their local communities and institutions. Outcomes & Evaluation: A pre-test/post-test study design was used to assess change in participant knowledge related to research ethics principles and practices. The mean score improved from 73% correct at baseline and 84% at course completion. Participants completed a course evaluation after the in-person and virtual components of the course. Participants highlighted the most useful topics in the course as respect for persons and human rights, principles of bioethics, informed consent and the function of research ethics committees. The most positive aspects of the in-person component of the course were the high level of participation, group work, communication and debate among participants representing different academic disciplines and social sectors. Eighty percent of participants completed the course with five dropping out during the virtual component. Most students reported that the instructions for using the virtual platform were clear and they received sufficient support from the Course Coordinator, however, most stated that some of the teachers provided insufficient academic support. Going Forward: Integrating the group interaction strengths of the in-person TOT component with the flexibility of the virtual component recommends using a mixed methods approach while providing additional training to teachers related to virtual teaching methodologies. Funding: NIH/FIC, International Research Ethics Education and Curriculum Development Award (R25)

Estudo da patogenia do vírus da raiva por meio de amostras ERA e PV administradas por via oral em hamsters (M. auratus)

Hamsters orally inoculated with ERA and PV strains of rabies virus were sacrificed at 24, 48, 72 hours, 21 and 30 days after inoculation. Brain fragments were examined by Fluorescent Antibody test (FAT) and heminested PCR (hn-PCR). Fragments from stomach, blood, heart, and lung were examined only by hn-PCR. Sera of other hamsters, similarly inoculated, obtained at 30th day after inoculation were submitted to mouse neutralization test. The hamsters were challenged intracerebrally with CVS strain with 10(2.7)mouse LD50/0.03mL, 45 days after inoculation. Brains examined by FAT were negative. The hn-PCR detected the presence of rabies virus RNA in the lung of one animal inoculated with ERA, and in the brain, stomach, blood, and lung of PV-infected animals. The orally inoculated virus was capable to infect and replicate in several organs and tissues; however, none of the challenged hamsters did survive after challenge.Hamsters inoculados oralmente com as amostras de vírus rábico ERA e PV foram sacrificados após 24, 48 e 72 horas, 21 e 30 dias. Fragmentos do cérebro foram analisados através da imunofluorescência direta (IFD) e heminested-PCR (hn-PCR). Os fragmentos do estômado, sangue, coração e pulmão foram examinados somente com a técnica de hn-PCR. Soros de outros hamsters, inoculados de modo similar e obtidos 30 dias após a inoculação, foram submetidos ao teste de soroneutralização (SNT) em camundongos. No 45º dia pós-inoculação, os hamsters foram desafiados intracerebralmente com a amostra CVS, contendo 10(2,7)DL50 em camundongos/0,03 mL. Os fragmentos do cérebro foram todos negativos ao teste de imunofluorescência. A hn-PCR detectou a presença de RNA do vírus da raiva no pulmão de um animal inoculado com a amostra ERA e, no cérebro, estômago, sangue e pulmão de hamsters inoculados com a amostra PV. As amostras de vírus inoculadas oralmente foram capazes de se replicar em diferentes órgãos, no entanto, todos od hamsters morreram ao desafio, indicando uma resposta imunológica insuficiente

Modelo de Z Altman y diagrama de solidez aplicado al mercado costarricense

Proyecto de graduación (Licenciatura en Administración de Empresas. Énfasis en Finanzas) Instituto Tecnológico de Costa Rica, Escuela de Administración de Empresas, 2015This project analyses the application of the Z Altman and Financial Strength models, as tools to predict financial insolvencies for ten companies listed at Bolsa Nacional de Valores, for the purpose to offer the investor ways to improve the decision making process. There is few information, and sometimes there is no information at all at the Bolsa Nacional de Valores and the different site webs of the companies analyzed for the national or foreign investor who wishes to participate in Costa Rica stock market. The investor does not have the tools needed to determine the financial strength of the companies at the Bolsa Nacional de Valores, so this is a great opportunity to effectuate a financial analysis that allows to determinate if the companies shows financial insolvency and an a solid financial structure. In order to effectuate this project it was required the acquisition of the several Financial Statements such as General Balance Sheet and the Income Statement for all the analyzed companies, the information was obtained at the site web of Superintendencia General de Valores (SUGEVAL). Once the models were applied to the companies, the results show three companies in a safe zone, with a few possibilities to have financial insolvency, while six present fluctuations between a safe and a precaution zone for the periods analyzed. Ad Astra Rockect shows some atypical conditions due to its nature, so it was excluded from the general analysis because the Z model is not totally applicable.Instituto Tecnológico de Costa Rica. Escuela de Administración de Empresa

Experiments on intramuscular inoculation and feeding domestic cats (Felis catus) with brains of mice previously infected by rabies viruses

Nineteen kittens divided into four groups were fed with brains of mice infected with rabies viruses. Each four kittens (group I) received four brains infected with the PV fixed strain; nine kittens (group II) ingested 4-5 brains infected with the field isolate T-9/95, isolated from the Desmodus rotundus vampire bat; two kittens (group III) fed ten T-9/95-infected brains, and four cats consumed 32-37 PV strain-infected brains. One adult male, inoculated into masseter muscle with a 20% T-9/95-infected brain suspension, presented rabies after an incubation period of six days, followed with 8 days of clinical evolution, and died thereafter and this cat was considered as the rabies "positive standard". After observing for 20-230 days, all the cats feeding the rabid brains were submitted to euthanasia, by using Acepran®, Zoletil®, and T-61®. At necropsy, samples of brain, heart, lung, kidney, submaxillary salivary gland, and cervical medulla were collected from all the cats and further submitted to the direct fluorescence antibody test (dFA), mouse inoculation test (MIT) and to the reverse transcriptase-polymerase chain reaction (RT-PCR) technique. Brain, cervical medulla, and the submaxillary salivary gland of the positive standard cat were dFA-positive, and brain and cervical medulla were positive for MIT. All specimens of this cat tested by the RT-PCR were found positive. No animals ingesting PV or T-9/95 virus-infected brains developed clinical signs and all materials tested were negative by dFA and MIT. Several specimens, however, showed positive reactions by the RT-PCR technique, but cats were resistant to rabies through the viruses administered orally.Dezenove gatos, divididos em quatro grupos, foram alimentados com cérebros de camundongos infectados com vírus de raiva. Cada um dos quatro gatos (grupo I) receberam quatro cérebros infectados com vírus fixo PV; nove gatos (grupo II) ingeriram 4-5 cérebros infectados com uma amostra de campo T-9/95, isolada do morcego Desmodus rotundus; dois gatos (grupo III) ingeriram 10 cérebros infectados com T-9/95 e quatro gatos (grupo IV) ingeriram 32-37 cérebros infectados com vírus PV. Um macho adulto, inoculado no músculo masséter, com uma suspensão cerebral a 20% da amostra T-9/95, desenvolveu raiva após período de incubação de seis dias, seguidos por oito dias de evolução clínica, morrendo em seguida. Este gato foi denominado de "padrão positivo". Após observação por um período de 20-230 dias, todos os gatos que receberam cérebros foram submetidos à eutanásia, utilizando Acepran®, Zoletil® e T-61®. À necropsia, foram colhidas amostras do cérebro, coração, pulmão, rim, glândula salivar submaxilar e medula cervical e submetidas à prova de imunofluorescência direta (IFD), inoculação em camundongos (IC), e reação em cadeia pela polimerase-transcriptase reversa (RT-PCR). No "padrão positivo", cérebro, medula cervical e glândula salivar foram positivos à IFD e à IC, cérebro e medula cervical foram os positivos. Todos os espécimes do "padrão positivo" foram positivos à RT-PCR. Nenhum animal que ingeriu cérebros contendo amostras de vírus PV ou T-9/95 apresentou sinais clínicos e todos os espécimes testados foram negativos à IFD e IC, no entanto, alguns espécimes reagiram positivamente à RT-PCR, porém, os gatos foram resistentes à raiva com vírus administrados oralmente