1,024 research outputs found
Melanoma maligno gastrointestinal de origen primario desconocido: Reporte de caso
One of the unusual characteristics of cutaneous melanoma is its ability to metastasize in the small intestine. It is often diagnosed during autopsies of cutaneous melanoma patients. Metastatic deposits have been found in 50% to 60% of these autopsies, but less than 2% to 4% of patients diagnosed with melanoma have gastrointestinal metastasis during the course of the disease. Between 4% and 9% of gastrointestinal melanoma cases have unknown primary tumors. Rapid identification and resection of melanoma in the digestive tract could improve the patient survival rate and prevent complications such as intestinal obstructions from occurring. We present a rare clinical case of gastrointestinal melanoma of unknown primary origin. The patient had a clinical picture of nausea, hyporexia, epigastralgia, fatigue, paresthesias in the right dorsal region and had lost nine kilograms in three weeks. An abdominal CT scan showed three predominantly isodense liver lesions in the parenchyma, with some areas of lower density located in segments 2,5,7 and 8 of the liver. These were biopsied. Upper digestive tract endoscopy took biopsy samples of two hyperpigmented lesions in the second portion of the duodenum. Histopathological examination showed malignant melanoma. All typical locations of primary melanoma were excluded during the diagnostic procedure. © 2019 Asociaciones Colombianas de Gastroenterología, Endoscopia digestiva, Coloproctología y Hepatología
Effect of clozapine on immunoglobulin M plasma levels
Clozapine is an atypical antipsychotic medication indicated for the treatment of patients who fail to respond to standard antipsychotic treatment. It possesses immunomodulatory properties and requires regular counts of white blood cells and absolute neutrophils. It has been reported to mediate several effects on humoral immunity, such as altering the levels of antibody-producing cytokines [Hinze-Selch et al. 1998].
Selective immunoglobulin M immunodeficiency (SIgMD) is a rare form of dysgammaglobulinaemia characterized by a selective, low level of immunoglobulin M (IgM) in conjunction with normal T cell numbers and function, and with no other identifiable immunodeficiencies. It can occur as either a primary or secondary condition and displays an estimated prevalence of 0.03%– 3%. Secondary SIgMD can be associated with malignancy, autoimmune disorders, gastrointestinal diseases and/or immunosuppressive treatments [Goldstein et al. 2006]..
Teacher participation & qualifications regarding extra-curricula sport activities
En la presente investigación se aborda el estudio y análisis de la intervención docente del profesorado de las actividades físico-deportivas extraescolares en los centros educativos de Educación Secundaria de la Comunidad de Madrid en función de su formación inicial. La investigación sigue una metodología cuantitativa de corte descriptivo, a través de la encuesta. El tamaño de la muestra es de 350 personas y para su cálculo se consideraron varios aspectos: la población era finita; se recurre en la varianza poblacional al supuesto más desfavorable donde “P” y “Q” son iguales con el 50% cada uno; el intervalo de confianza es del 95,5%, con un margen de error del ± 4,75%. Los resultados revelan que existe un alto porcentaje de profesores que no realizan una programación de sus actividades ni tampoco evalúan a sus alumnos. Asimismo, los resultados sugieren que la intervención docente de las personas no tituladas es menos adecuada.In this research is done the study and analysis of teacher intervention in the extra-curricular sport activities of educational centres for secondary education in Comunidad de Madrid. The research follows a quantitative methodology with a descriptive profile which, across survey, in which a cross-sectional survey have been carried out.The size of the sample is 350 people and for its calculation, several aspects have been considered: The population was finite; the least favourable hypothesis is considered in the population variation, where “P” and “Q” are equal, with 50% each; the confidence interval is 95%, with an error margin of ± 4.75%. The results reveal that exits a high percentage of teachers who don’t programme their activities and don’t evaluate their students. Furthermore, the results suggest that the teacher intervention is less adequate to the teachers who don’t have any qualification
Phylogenetic Relationships among North American Popcorns and Their Evolutionary Links to Mexican and South American Popcorns
To determine genetic relationships among representative popcorns (Zea mays L.) of the New World, 56 maize populations from the USA and nine Latin American countries were characterized for 29 morphological traits, 18 isozyme loci, and 31 SSR loci. Cluster and principal component analyses were performed upon standardized morphological data and allelic frequencies from isozyme and SSR loci to elucidate relationships among populations within a geographical and historical context. Three groups of popcorn, with distinctive morphological characteristics and genetic profiles, were identified in the North American populations. The first group includes the North American Yellow Pearl Popcorns, which are currently the most important for U.S. commercial production. This group could be derived from introductions of the race Curagua from Chile into New England in the 19th Century. The second group includes the North American Pointed Rice Popcorns, which probably originated from the complex of traditional races of pointed popcorns from Latin America, such as Palomero Toluqueño, Confite Puntiagudo, Canguil, and Pisankalla, which diffused from the highlands of central Mexico into northern Mexico and then into southwestern USA. The third group includes the North American Early Popcorns, which show a marked influence of Northern Flint maize, from which they probably acquired the trait of early maturity. This third group also shows genetic influences of maize from northwestern Mexico and even from early European varieties of popcorn introduced late in the 19th Century. We propose that the three groups of North American popcorn identified in this study be recognized taxonomically as distinct races, and we provide characteristic traits as well as isozyme and SSR alleles to define the new races
Effects of impurities on the ice microstructure of Monte Perdido Glacier, Central Pyrenees, NE Spain
Monte Perdido Glacier, located in the central Pyrenees, is one of the southernmost glaciers in Europe. Due to climate change, this glacier is suffering an accelerated mass loss, especially in the last decades. If the current trends persist, this glacier is expected to disappear in the next 50 years. As part of the efforts of the scientific community to increase the knowledge about this glacier, this research presents the first microstructural characterization of the Monte Perdido Glacier, focused on a high-impurity concentration segment that belongs to an ice core drilled in 2017. The results reveal the ice has a layering defined by air bubbles and non-soluble impurities. The bubble-defined layering exhibits features of both a primary (sedimentary) and a secondary (strain-induced) origin. We found a clear inverse correspondence between the particle concentration and the grains' size and roundness index. A preliminary micro-Raman characterization of the particles shows the occurrence of atacamite, anatase (likely related to ancient mining activities in the vicinity of the glacier) and quartz. The latter could be an indicator of mineral dust, probably suggesting the arrival of dust-laden air masses from the north of the African continent.This research was supported by the Spanish Government through the María de Maeztu excellence accreditation 2018–2022 (MDM-2017-0714) and by the Spanish Agencia Estatal de Investigación (AEI Spain) through the projects PaleoICE EXPLORA (CGL2015-72167-EXP) and iMechPro (RTI2018-100696-B-I00). NGS acknowledges a PhD grant from the Basque Government (PRE-2018-1-0116). We thank the directorate of the Parque Nacional de Ordesa y Monte Perdido (Spain) for permission to investigate the Monte Perdido glacier. We also thank Ibai Rico ( https://basquemountainguides.com/ , UPV/EHU), Maria Leunda (UPV/EHU), and Juan Ignacio López-Moreno (IPE-CSIC) for their help during the sampling of the MP1 ice core, and Pedro Sanchez Navarrete (IPE-CSIC) for transporting the ice samples. Finally, we would like to extend our appreciation to the anonymous reviewers, the Scientific Editor, Christine Hvidberg, and the Chief Editor, Hester Jiskoot, for their valuable comments on this manuscript
Correlated-informed neural networks: a new machine learning framework to predict pressure drop in micro-channels
Accurate pressure drop estimation in forced boiling phenomena is important
during the thermal analysis and the geometric design of cryogenic heat
exchangers. However, current methods to predict the pressure drop have one of
two problems: lack of accuracy or generalization to different situations. In
this work, we present the correlated-informed neural networks (CoINN), a new
paradigm in applying the artificial neural network (ANN) technique combined
with a successful pressure drop correlation as a mapping tool to predict the
pressure drop of zeotropic mixtures in micro-channels. The proposed approach is
inspired by Transfer Learning, highly used in deep learning problems with
reduced datasets. Our method improves the ANN performance by transferring the
knowledge of the Sun & Mishima correlation for the pressure drop to the ANN.
The correlation having physical and phenomenological implications for the
pressure drop in micro-channels considerably improves the performance and
generalization capabilities of the ANN. The final architecture consists of
three inputs: the mixture vapor quality, the micro-channel inner diameter, and
the available pressure drop correlation. The results show the benefits gained
using the correlated-informed approach predicting experimental data used for
training and a posterior test with a mean relative error (mre) of 6%, lower
than the Sun & Mishima correlation of 13%. Additionally, this approach can be
extended to other mixtures and experimental settings, a missing feature in
other approaches for mapping correlations using ANNs for heat transfer
applications
Compensación de bases imponibles negativas: exceso de imposición
Nuestro sistema fiscal configura a las personas jurídicas como entidades con capacidad económica y tributaria autónoma diferenciada de la de sus socios, siendo el Impuesto sobre Sociedades el tributo que grava la renta obtenida por aquéllas a lo largo de períodos impositivos no superiores a doce meses con independencia de que se reparta o no el beneficio de la sociedad, tomando este impuesto la naturaleza de un gravamen en la fuente a cuenta de la tributación de los rendimientos del capital obtenido por los socios como consecuencia de la aportación de recursos a la sociedad por cuanto aquel impuesto se deducirá, si bien parcialmente, en la liquidación del socio en el ejercicio en que se perciba el dividendo con cargo a los beneficios generados por la entidad de la que es partícipe
“Education Network” a new way to teach Chemistry
The complexity of chemistry has implications for the teaching of chemistry. That chemistry is a very complex subject. The majority of the students at University think that chemistry is a difficult discipline and they have difficulty in understanding the concepts. Moreover, students' interest in chemistry decreases the first year at university. The reason for this decrease might be that the contents of chemistry laboratory classes are boring, out of date and lacking of dynamism that students experience through visual media tools.
For these reasons, new programs and methodologies should be developed. Those are based on making chemistry relevant through problem solving and collaborative learning hold promise for reforming chemistry education. It is about an education according to circumstances, which is adapted to context and virtual behaviour of people.
It's time to CRUSH boredom by transforming your classroom into an Escape Room adventure. School-based escape games are a great teaching tool. The students while playing, learn. The most important point is that they won’t realize they’re doing both at the same time.
In this work, an educational gamification experience based on the escape room concept was developed. The first (Do It Yourself) DIY Escape Room was built the year before at Mechanical Engineer Degree started, that took more than three weeks of work. It was presented to other professors to the same subject at different degrees. That DIY Escape Room was modified and adapted to each group. Each professor changed the clues, problems and so on in order to orientate the topic as much as possible to their students.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Analysis of plasmaspheric hiss wave amplitudes inferred from low-altitude POES electron data: Technique sensitivity analysis
A novel technique capable of inferring wave amplitudes from low-altitude electron measurements from the Polar Operational Environmental Satellites (POES) spacecraft has been previously proposed to construct a global dynamic model of chorus and plasmaspheric hiss waves. In this paper we focus on plasmaspheric hiss, which is an incoherent broadband emission that plays a dominant role in the loss of energetic electrons from the inner magnetosphere. We analyze the sensitivity of the POES technique to different inputs used to infer the hiss wave amplitudes during three conjunction events with the Van Allen Probes. These amplitudes are calculated with different input models of the plasma density, wave frequency spectrum, and electron energy spectrum, and the results are compared to the wave observations from the twin Van Allen Probes. Only one parameter is varied at a time in order to isolate its effect on the output, while the two other inputs are set to the values observed by the Van Allen Probes. The results show that the predicted hiss amplitudes are most sensitive to the adopted frequency spectrum, followed by the plasma density, but they are not very sensitive to the electron energy spectrum. Moreover, the standard Gaussian representation of the wave frequency spectrum (centered at 550 Hz) peaks at frequencies that are much higher than those observed in individual cases as well as in statistical wave distributions, which produces large overestimates of the hiss wave amplitude. For this reason, a realistic statistical model of the wave frequency spectrum should be used in the POES technique to infer the plasmaspheric hiss wave intensity rather than a standard Gaussian distribution, since the former better reproduces the observed plasmaspheric hiss wave amplitudes
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