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Abstract Background Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments. Methods This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016–September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study. Results A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%. Conclusions The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.

In this paper, we present an impulsive pinning control algorithm for discrete-time complex networks with different node dynamics, using a linear algebra approach and a neural network as an identifier, to synthesize a learning control law. The model of the complex network used in the analysis has unknown node self-dynamics, linear connections between nodes, where the impulsive dynamics add feedback control input only to the pinned nodes. The proposed controller consists of the linearization for the node dynamics and a reorder of the resulting quadratic Lyapunov function using the Rayleigh quotient. The learning part of the control is done with a discrete-time recurrent high order neural network used for identification of the pinned nodes, which is trained using an extended Kalman filter algorithm. A numerical simulation is included in order to illustrate the behavior of the system under the developed controller. For this simulation, a 20-node complex network with 5 different node dynamics is used. The node dynamics consists of discretized versions of well-known continuous chaotic attractors.

Fine-grained change detection in sensor data is very challenging for artificial intelligence though it is critically important in practice. It is the process of identifying differences in the state of an object or phenomenon where the differences are class-specific and are difficult to generalise. As a result, many recent technologies that leverage big data and deep learning struggle with this task. This review focuses on the state-of-the-art methods, applications, and challenges of representation learning for fine-grained change detection. Our research focuses on methods of harnessing the latent metric space of representation learning techniques as an interim output for hybrid human-machine intelligence. We review methods for transforming and projecting embedding space such that significant changes can be communicated more effectively and a more comprehensive interpretation of underlying relationships in sensor data is facilitated. We conduct this research in our work towards developing a method for aligning the axes of latent embedding space with meaningful real-world metrics so that the reasoning behind the detection of change in relation to past observations may be revealed and adjusted. This is an important topic in many fields concerned with producing more meaningful and explainable outputs from deep learning and also for providing means for knowledge injection and model calibration in order to maintain user confidence.

Esta entrevista foi realizada por Luana Wunsch, Doutorado em Educação, Universidade de Lisboa, Professora Programa de Pós-Graduação Stricto Sensu em Educação - Mestrado Profissional: Educação e Novas Tecnologias (PPGENT), Escola Superior de Educação, Centro Universitário Internacional – UNINTER. O assunto versa sobre prática pedagógica e inovação. Participou da entrevista o professor Daniel Ríos Muñoz, Doctor em Educación, Profesor Universidad de Santiago de Chile​, Área de Trabajo: Evaluación y Medición Educacional. Estão indicadas as questões e em seguida as respostas.

As Eleições 2014 ficaram marcadas no imaginário popular brasileiro como as “eleições dos memes”. Sob o ponto de vista científico, porém, acredita-se que há ainda raras tentativas de compreender o que o fenômeno dos memes, no ambiente da internet, representa para a Comunicação Política. Este trabalho propõe-se a expor resultados preliminares de investigação sobre os usos e as apropriações de memes político-eleitorais. O principal objetivo é desenvolver, a partir de propostas anteriores, uma matriz taxonômica capaz de auxiliar pesquisadores interessados no tema a tratarem dos memes com maior objetividade. Para tanto, procurou-se realizar uma análise de conteúdo sobre memes que circularam durante os debates eleitorais presidenciais em 2014. Os resultados apontam para a necessidade de avaliarmos a produção de sentido de internautas sobre a cena política, percebendo os memes como expressão de uma opinião pública capaz de ler a performance dos candidatos através de comentários sociais nas mídias digitais.

In this work, a neural impulsive pinning controller for a twenty-node dynamical discrete complex network is presented. The node dynamics of the network are all different types of discrete versions of chaotic attractors of three dimensions. Using the V-stability method, we propose a criterion for selecting nodes to design pinning control, in which only a small fraction of the nodes is locally controlled in order to stabilize the network states at zero. A discrete recurrent high order neural network (RHONN) trained with extended Kalman filter (EKF) is used to identify the dynamics of controlled nodes and synthesize the control law.

Resumen Este artículo tiene por objetivo principal ser un aporte a las discusiones y reflexiones sobre el rol formativo de la evaluación por competencias en el ámbito educativo. Se plantea su relación con los perfiles curriculares que se orientan a los nuevos contextos laborales. Se sostiene la necesidad de establecer lineamientos, diseños, implementaciones y desarrollos instrumentales para determinar los impactos de los aprendizajes por competencias como una forma de evidenciar la apropiación de saberes integrales complejos. Se asume el desafío que tiene la práctica evaluativa por competencias al incorporar a los principales actores del proceso de enseñanza y aprendizaje, a objeto de realizar una evaluación más participativa y democrática. Para ello se realiza una breve descripción y análisis teórico-conceptual sobre las competencias en el mundo educativo. Se profundiza sobre la evaluación por competencias como una nueva práctica evaluativa destacando los criterios integrales y formativos de estas prácticas. Se analiza cómo la evaluación por competencias puede orientar e influir en el mejoramiento de los aprendizajes y prácticas pedagógicas. Para concluir se plantean unas consideraciones finales de la evaluación por competencias a modo de balance y desafíos para el ámbito educativo, sobre todo aquellos relacionados por la preocupación en el proceso previo al resultado final de un producto de aprendizaje.

Background: The association between high-sensitivity C-reactive protein and recurrent major adverse cardiovascular events (MACE) in patients with ST-elevation myocardial infarction who undergo primary percutaneous coronary intervention remains controversial. Objective: To investigate the potential association between high-sensitivity C-reactive protein and an increased risk of MACE such as death, heart failure, reinfarction, and new revascularization in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods: This prospective cohort study included 300 individuals aged >18 years who were diagnosed with ST-elevation myocardial infarction and underwent primary percutaneous coronary intervention at a tertiary health center. An instrument evaluating clinical variables and the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores was used. High-sensitivity C-reactive protein was determined by nephelometry. The patients were followed-up during hospitalization and up to 30 days after infarction for the occurrence of MACE. Student's t, Mann-Whitney, chi-square, and logistic regression tests were used for statistical analyses. P values of ≤0.05 were considered statistically significant. Results: The mean age was 59.76 years, and 69.3% of patients were male. No statistically significant association was observed between high-sensitivity C-reactive protein and recurrent MACE (p = 0.11). However, high-sensitivity C-reactive protein was independently associated with 30-day mortality when adjusted for TIMI [odds ratio (OR), 1.27; 95% confidence interval (CI), 1.07-1.51; p = 0.005] and GRACE (OR, 1.26; 95% CI, 1.06-1.49; p = 0.007) risk scores. Conclusion: Although high-sensitivity C-reactive protein was not predictive of combined major cardiovascular events within 30 days after ST-elevation myocardial infarction in patients who underwent primary angioplasty and stent implantation, it was an independent predictor of 30-day mortality.

Many natural prion diseases of humans and animals are considered to be acquired through oral consumption of contaminated food or pasture. Determining the route by which prions establish host infection will identify the important factors that influence oral prion disease susceptibility and to which intervention strategies can be developed. After exposure, the early accumulation and replication of prions within small intestinal Peyer's patches is essential for the efficient spread of disease to the brain. To replicate within Peyer's patches, the prions must first cross the gut epithelium. M cells are specialised epithelial cells within the epithelia covering Peyer's patches that transcytose particulate antigens and microorganisms. M cell-development is dependent upon RANKL-RANK-signalling, and mice in which RANK is deleted only in the gut epithelium completely lack M cells. In the specific absence of M cells in these mice, the accumulation of prions within Peyer's patches and the spread of disease to the brain was blocked, demonstrating a critical role for M cells in the initial transfer of prions across the gut epithelium in order to establish host infection. Since pathogens, inflammatory stimuli and aging can modify M cell-density in the gut, these factors may also influence oral prion disease susceptibility. Mice were therefore treated with RANKL to enhance M cell density in the gut. We show that prion uptake from the gut lumen was enhanced in RANKL-treated mice, resulting in shortened survival times and increased disease susceptibility, equivalent to a 10-fold higher infectious titre of prions. Together these data demonstrate that M cells are the critical gatekeepers of oral prion infection, whose density in the gut epithelium directly limits or enhances disease susceptibility. Our data suggest that factors which alter M cell-density in the gut epithelium may be important risk factors which influence host susceptibility to orally acquired prion diseases.

The probiotic yeast Saccharomyces boulardii has been shown to ameliorate disease severity in the context of many infectious and inflammatory conditions. However, use of S. boulardii as a prophylactic agent or therapeutic delivery vector would require delivery of S. boulardii to a healthy, uninflamed intestine. In contrast to inflamed mucosal tissue, the diverse microbiota, intact epithelial barrier, and fewer inflammatory immune cells within the healthy intestine may all limit the degree to which S. boulardii contacts and influences the host mucosal immune system. Understanding the nature of these interactions is crucial for application of S. boulardii as a prophylactic agent or therapeutic delivery vehicle. In this study, we explore both intrinsic and immunomodulatory properties of S. boulardii in the healthy mucosal immune system. Genomic sequencing and morphological analysis of S. boulardii reveals changes in cell wall components compared to non-probiotic S. cerevisiae that may partially account for probiotic functions of S. boulardii. Flow cytometry and immunohistochemistry demonstrate limited S. boulardii association with murine Peyer's patches. We also show that although S. boulardii induces a systemic humoral immune response, this response is small in magnitude and not directed against S. boulardii itself. RNA-seq of the draining mesenteric lymph nodes indicates that even repeated administration of S. boulardii induces few transcriptional changes in the healthy intestine. Together these data strongly suggest that interaction between S. boulardii and the mucosal immune system in the healthy intestine is limited, with important implications for future work examining S. boulardii as a prophylactic agent and therapeutic delivery vehicle.

Un equipo universitario multidisciplinario ha desarrollado una innovación integral en cuatro establecimientos educacionales secundarios, a partir del diseño, instalación y consolidación de procesos autosustentables en la gestión directiva, pedagógica y de convivencia e inclusión, con el propósito de promover un mejoramiento significativo en la calidad de los aprendizajes de los estudiantes de sectores sociales de alta vulnerabilidad. Este programa de asesoría se ha llevado a cabo a través de la implementación de un plan de acción que consideró principalmente a los directivos, los docentes y los estudiantes. Se plantearon reuniones periódicas con los equipos directivos, entrevistas y capacitación docente en metodologías participativas, prácticas evaluativas y utilización de tecnologías de información y comunicación. Además, se trabajó directamente con los estudiantes por medio de talleres, charlas y entrevistas. Dentro de los resultados de esta asesoría se destacan: la apropiación de un plan de gestión por parte de los directivos, el mejoramiento de las prácticas docentes y una mayor disposición hacia los aprendizajes por parte de los estudiantes que participaron en los programas orientados hacia ellos, además de una mejor convivencia entre los estudiantes y entre éstos y los docentes

Vibrio cholerae is a natural inhabitant of many aquatic environments in the world. Biotypes harboring similar virulence-related gene clusters are the causative agents of epidemic cholera, but the majority of strains are harmless to humans. Since 1971, environmental surveillance for potentially pathogenic V. cholerae has resulted in the isolation of many strains from the Brazilian Amazon aquatic ecosystem. Most of these strains are from the non-O1/non-O139 serogroups (NAGs), but toxigenic O1 strains were isolated during the Latin America cholera epidemic in the region (1991-1996). A collection of environmental V. cholerae strains from the Brazilian Amazon belonging to pre-epidemic (1977-1990), epidemic (1991-1996), and post-epidemic (1996-2007) periods in the region, was analyzed. The presence of genes related to virulence within the species and the genetic relationship among the strains were studied. These variables and the information available concerning the strains were used to build a Bayesian multivariate dependency model to distinguish the importance of each variable in determining the others. Some genes related to the epidemic strains were found in environmental NAGs during and after the epidemic. Significant diversity among the virulence-related gene content was observed among O1 strains isolated from the environment during the epidemic period, but not from clinical isolates, which were analyzed as controls. Despite this diversity, these strains exhibited similar PFGE profiles. PFGE profiles were significant while separating potentially epidemic clones from indigenous strains. No significant correlation with isolation source, place or period was observed. The presence of the WASA-1 prophage significantly correlated with serogroups, PFGE profiles, and the presence of virulence-related genes. This study provides a broad characterization of the environmental V. cholerae population from the Amazon, and also highlights the importance of identifying precisely defined genetic markers such as the WASA-1 prophage for the surveillance of cholera.

The intention of this research is to establish a relationship between dairy cattle diseases with various non-invasive sensors for the development of a health monitoring system. This paper expands on the conference paper titled “Sensor technology for animal health monitoring” published in the International Journal on Smart Sensing and Intelligent Systems (s2is) for the proceedings of International Conference on Sensing Technology (ICST) 2014. This paper studies and explores particular characteristics of dairy cattle’s health and behavioural symptoms. The aim is to consider the nature of the diseases a cow may have and relate it with one or many sensors that are suitable for accurate measurement of the behavioural changes. The research uses ontological relationship mapping or ontology matching to integrate heterogeneous databases of diseases and sensors and explains it in detail. This study identifies the sensors needed to determine illnesses in a dairy cow and how they would be beneficial for the development of non-invasive, wearable, smart, dairy cattle health monitoring system to be placed on the cows’ neck. It also explains how the primary sensors identified by this research can be used to forecast cattle health in a simple, basic manner. The scope of this paper is limited to the discussion about the non-invasive, wearable sensors that are needed to determine the cattle diseases. We focused only on non-invasive sensors because they are easy to install on cows and no training is required for them to be installed as compared to invasive sensors. Development of such a system and its evaluation is not in the scope of this paper and is left for our next paper.

The 7th cholera pandemic reached Latin America in 1991, spreading from Peru to virtually all Latin American countries. During the late epidemic period, a strain that failed to ferment sucrose dominated cholera outbreaks in the Northern Brazilian Amazon region. In order to understand the genomic characteristics and the determinants of this altered sucrose fermenting phenotype, the genome of the strain IEC224 was sequenced. This paper reports a broad genomic study of this strain, showing its correlation with the major epidemic lineage. The potentially mobile genomic regions are shown to possess GC content deviation, and harbor the main V. cholera virulence genes. A novel bioinformatic approach was applied in order to identify the putative functions of hypothetical proteins, and was compared with the automatic annotation by RAST. The genome of a large bacteriophage was found to be integrated to the IEC224's alanine aminopeptidase gene. The presence of this phage is shown to be a common characteristic of the El Tor strains from the Latin American epidemic, as well as its putative ancestor from Angola. The defective sucrose fermenting phenotype is shown to be due to a single nucleotide insertion in the V. cholerae sucrose-specific transportation gene. This frame-shift mutation truncated a membrane protein, altering its structural pore-like conformation. Further, the identification of a common bacteriophage reinforces both the monophyletic and African-Origin hypotheses for the main causative agent of the 1991 Latin America cholera epidemics.

Este texto revisa de qué manera la metodología, la evaluación del aprendizaje, la relación profesor-estudiante y las relaciones entre los estudiantes inciden en el tipo de ambiente social generado al interior del aula universitaria.

Este estudio tiene como objetivo develar las principales características personales y profesionales de los profesores que efectúan transformaciones positivas en su práctica pedagógica.

La mayor parte de las acciones desarrolladas en el marco de la Reforma Educacional Chilena buscan promover la acción innovadora de los profesores, con el propósito de que su actividad docente contribuya al mejoramiento de los aprendizajes de los estudiantes. Una de las estrategias más novedosa para despertar la capacidad de innovar de los docentes está constituida por los Proyectos de Mejoramiento Educativo (PME). En esta ponencia se describe y analiza los diferentes resultados no previstos de las innovaciones -independientes de los PME- desarrolladas por profesores de educación básica, y que no estaban contemplados originalmente en sus objetivos. Esta situación hace pensar que el profesor innovador no posee un control pleno en el desarrollo de la innovación, lo que lo obliga a asumir un cierto grado de incertidumbre durante su ejecución. Este hallazgo tiende a cuestionar el modelo de Investigación y Desarrollo que ha orientado diversos procesos innovadores basados en una racionalidad instrumental, y cuyos conceptos claves se relacionan con control, eficiencia y eficacia. En el caso de los estudiantes, los principales aprendizajes no previstos se relacionan con un mayor desarrollo de características afectivas y actitudinales como: incremento en la participación escolar, mayor identificación con la unidad educativa, aumento en el compañerismo entre alumnos, mejor relación con sus profesores y mejores aprendizajes cognoscitivos. Sin embargo, también se observan efectos no previstos de carácter negativo como: envidia, individualismo, competencia, autoritarismo, indisciplina, entre otros. En los profesores innovadores, se aprecian efectos no previstos vinculados a la aplicación de estrategias de enseñanza más activas, un mayor interés en el perfeccionamiento de temáticas ligadas a la acción de mejoramiento y una mayor comunicación con otros profesores del establecimiento acerca de la innovación ejecutada.

La deformidad de Madelung constituye un hallazgo común de varias patologías que afectan a la muñeca, con alteraciones características en el radio, carpo y cúbito, siendo la configuración triangular del carpo y la inclinación cubital de la epífisis distal del radio los más característicos. Puede ser visto en radiografía simple, tomografía computada o resonancia magnética. Como radiólogos, debemos conocer los criterios recomendados en la actualidad, teniéndolos presentes para su diagnóstico precoz en pacientes jóvenes o cuando la deformidad ya está establecida en pacientes de edad más avanzada.

La enfermedad renal crónica es un problema de salud pública a nivel mundial, siendo los trastornos de la mineralización y el metabolismo óseo problemas comunes asociados a esta enfermedad, que causan una importante morbilidad y un deterioro de la calidad de vida. La expresión de los hallazgos en la enfermedad renal crónica puede sistematizarse con base en la clasificación propuesta por la conferencia internacional Kidney Disease: Improving Global Outcomes, que las divide en trastornos del metabolismo del calcio y el fósforo (sin hallazgos en imágenes), alteración de la estructura y la composición del hueso, y calcificaciones extraesqueléticas. Estos trastornos otorgan patrones radiológicos característicos, como son la resorción y esclerosis ósea, tumores pardos, osteomalacia-raquitismo, osteopenia y calcificaciones extraesqueléticas, además de los trastornos asociados al tratamiento de la falla renal crónica. En el presente artículo se sistematizarán y actualizarán los conceptos relacionados con los trastornos del metabolismo y la mineralización ósea, asociados a la enfermedad renal crónica y la osteodistrofia renal, mostrando sus diversas manifestaciones en radiología.

Resumen. Las fracturas triplanares (FT) son un tipo especial de fracturas que se producen clásicamente en la tibia distal, en un grupo etario acotado y que requieren un tratamiento específico. Su diagnóstico debe ser oportuno para evitar complicaciones y secuelas irreparables, por lo que las imágenes cumplen un rol fundamental. Se realiza una revisión sobre las FT y una muestra de casos para comprender cómo se generan y así realizar un adecuado diagnóstico de ellas.