184 research outputs found

    Theoretical lattices and formal concept analysis, tools for metatheoretic structuralism

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    We propose to take advantage of the computational methodologies of formal concept analysis and network visualization to represent and study the internal structure of axiomatized theories. This exercise was put into practice by comparing more than 44 theoretical models of space-time and gravitation. The lattices can be explored with interactive visualizations known as macroscopes that highlight relations of specialization, theorization, hierarchical orderings, communities and classes of components. In this text we exemplify with the reconstruction of classical particle mechanics, theories of space-time and gravitation

    Design and implementation of an efficient hardware integer motion estimator for an HEVC video encoder

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    High-Efficiency Video Coding (HEVC) was developed to improve its predecessor standard, H264/AVC, by doubling its compression efficiency. As in previous standards, Motion Estimation (ME) is one of the encoder critical blocks to achieve significant compression gains. However, it demands an overwhelming complexity cost to accurately remove video temporal redundancy, especially when encoding very high-resolution video sequences. To reduce the overall video encoding time, we propose the implementation of the HEVC ME block in hardware. The proposed architecture is based on (a) a new memory scan order, and (b) a new adder tree structure, which supports asymmetric partitioning modes in a fast and efficient way. The proposed system has been designed in VHDL (VHSIC Hardware Description Language), synthesized and implemented by means of the Xilinx FPGA, Virtex-7 XC7VX550T-3FFG1158. Our design achieves encoding frame rates up to 116 and 30 fps at 2 and 4K video formats, respectively

    Comments on: Implications of structural variations in the human sacrum: why is an anatomical classification crucial?

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    We sincerely appreciate the work done by Mahato [1] in which a qualitative classification of the sacrum is done to determine the number of segments, position of auricular surfaces, symmetry and abnormalities. This work is of the utmost importance since it is crucial for several surgical interventions and at the same time correlates certain pathologies with the morphology, mostly low back pai

    Factores Socioeconómicos y Motivacionales que Afectan el Rendimiento Escolar de los Estudiantes de la Facultad de Ciencias Económicas Administrativas de la Unacar

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    At present, it is not well seen that the education of a country has high rates of failure, or a low level of school performance, as this has implications for the economy and growth of the country. For this reason, governments have increasingly invested in quality education, establishing educational policies and allocating resources to reduce the factors that prevent countries from reaching the expected educational quality. One of these factors is the low academic performance and to increase it, it is necessary to identify the factors that affect its occurrence. The present investigation seeks to identify the factors that affect the academic performance of the students of the Faculty of Economic Administrative Sciences of the Autonomous University of the Carmen, through a descriptive study, based on a qualitative analysis about the detection of the indicators that have greater impact on the student’s academic performance index. The results show that students who fail most, not only study, but also work, which prevents them from devoting more time to study. Another important factor is the lack of interest in the subject.En la actualidad, no es bien visto que la educación presente altos índices de reprobación, o un bajo nivel de desempeño escolar, ya que ello tiene implicaciones en la economía y crecimiento del país. Por esa razón los gobiernos deciden, cada vez más, invertir en educación de calidad, estableciendo las políticas educativas y destinando los recursos que permitan disminuir los factores que impiden alcanzar la calidad educativa esperada. Uno de esos factores es el bajo desempeño académico, y para combatirlo es necesario identificar los factores que inciden para que se produzca. La presente investigación está dirigida a identificar los factores que afectan el desempeño académico de los estudiantes de la Facultad de Ciencias Económicas Administrativas de la Universidad Autónoma del Carmen, por medio de un estudio descriptivo, basado en un análisis cualitativo sobre la detección de los indicadores que reflejan mayor impacto en el índice de rendimiento académico de los estudiantes. Los resultados muestran que la mayoría de los estudiantes que reprueban, no solo estudian, sino que además trabajan, lo que les impide dedicar mayor tiempo al estudio. Otro factor importante es la falta de interés por la materia

    Low dose of sublingual immunotherapy in patients with allergic rhinitis in a randomized double-blind placebocontrolled study

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    Background: Few placebo controlled studies for sublingual immunotherapy (SLIT) have been performed so far in Latin America, and some issues like treatment scheme and doses remain uncertain Objective: to asses improvement in nasal, pharyngeal and ocular symptoms with low doses of SLIT to Dermatophagoides pteronyssinus comparing it with a placebo, in a Mexican population with allergic rhinitis (AR). Methods: a prospective, double-blind placebo-controlled, randomized study, with 32, patients with chronic, moderate to severe AR; 16 patients were treated with SLIT and 16 with placebo for 6 months with a total dose of D. pteronyssinus (Der p1) of 50.4 mcg. Nasal, pharyngeal and ocular symptoms were monitored using a symptoms diary to evaluate the degree of improvement and reduction in the use of medication. Results: Significant lower symptom and drug scores were found in SLIT group where 85% of patients showed clinical improvement. On the placebo group, 24% of patients improved and 76% had no response or worsened; 94% of patients on SLIT required less symptomatic medication compared with the placebo group. There was a reduction in positivity to cutaneous test to D. pteronyssinus in 50% of the patients on SLIT, whereas placebo patients remained all positiv

    Efecto de la aplicación intrauterina de ozono sobre la migración de neutrófilos y la endometritis subclínica en ganado lechero

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    The objective was to determine whether an ozonized saline solution (O3SS) increases endometrial polymorphonuclear neutrophils (PMNN) (Exp 1) and to challenge the preventive effect of O3SS on subclinical endometritis (SCE) (Exp 2). In Exp 1, 38 primiparous Holstein cows were used. Cows with (WHM) and no history of postpartum metritis (NHM) were included; they were then divided into control (CTRL, saline solution) or O3SS (6.7 ± 0.3 ppm) subgroups. At 55 d postpartum, 50 ml of CTRL or O3SS was applied intrauterinely and at 48 h, the quantity of PMNN was recorded by endometrial cytology. In Exp 2, 26 primiparous NHM Holstein cows were used. The cows were randomly distributed in CTRL or O3SS. Two doses of 50 ml were administered with an interval of 7 d (first application 11.3 ± 0.4 d postpartum). At d 30 postpartum, SCE (≥6 % PMNN) was diagnosed. WHM cows had higher numbers of endometrial PMNN compared to NHM cows (13.9 ± 6.2 vs 1.0 ± 0.46, P0.05) and the NHM-CTRL and NHM-O3SS groups (0.1 ± 0.1 and 1.8 ± 4.8, P>0.05) were not different. A statistical trend (P=0.09) of lower percentage of SCE was observed in the CTRL group compared to O3SS (15.4 and 46.2 %, respectively). In conclusion, transcervical O3SS does not increase the number of endometrial PMNN and preventive treatment with O3SS applied to NHM cows did not decrease SCE. The results suggest a possible anti-inflammatory effect of the ionized saline solution treatment.El objetivo fue determinar si una solución salina ozonizada (SSO3) incrementa los neutrófilos polimorfonucleares (NPMN) endometriales (Exp 1) y desafiar el efecto preventivo de SSO3 sobre la endometritis subclínica (ESC) (Exp 2). En el Exp 1 se utilizaron 38 vacas Holstein primíparas. Se incluyeron vacas con (CAM) y sin antecedentes de metritis postparto (SAM); posteriormente se repartieron en subgrupos control (CTRL, solución salina) o SSO3 (6.7 ± 0.3 ppm). A los 55 días postparto se aplicó 50 ml de CTRL o SSO3 intrauterinamente y a las 48 h se registró la cantidad de NPMN por citología endometrial. En el Exp 2 se utilizaron 26 vacas Holstein primíparas SAM. Las vacas se repartieron aleatoriamente en CTRL o SSO3. Se administraron dos dosis de 50 ml con intervalo de 7 días (primera aplicación 11.3 ± 0.4 días postparto). Al día 30 postparto se diagnosticó ESC (≥6% NPMN). Las vacas CAM tuvieron mayor número de NPMN endometriales comparado con vacas SAM (13.9 ± 6.2 vs 1.0±0.46, P0.05) y SAM-CTRL y SAM-SSO3 (0.1 ± 0.1 y 1.8 ± 4.8, P>0.05) no fueron diferentes. Se observó una tendencia estadística (P=0.09) de menor porcentaje de ESC en grupo CTRL comparado con SSO3 (15.4 y 46.2 %, respectivamente). En conclusión, la SSO3 por vía transcervical no incrementa el número de NPMN endometriales y el tratamiento preventivo con SSO3 aplicado a vacas SAM no disminuyó la ESC. Los resultados sugieren un posible efecto antiinflamatorio del tratamiento solución salina ionizada

    Estado del conocimiento y la práctica del autoexamen de mama en las mujeres trabajadoras en servicios varios de Areandina-Pereira durante el periodo 2020-2

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    El autoexamen de mama es una práctica que empodera a las mujeres haciendo que estas se responsabilicen de su propia salud, y en consecuencia, fomenten y perfeccionen la autoexploración, promoviendo así la toma de conciencia entre las mujeres y apoyando de este modo el método de cribado, el cual consiste en la aplicación sistemática de pruebas de tamizaje en poblaciones asintomáticas, con el objetivo es detectar anomalías indicativas de cáncer. Con este proyecto se pretende identificar, de manera descriptiva, el conocimiento y la práctica del autoexamen de mama en las mujeres trabajadoras en servicios varios de Areandina - Pereira en el periodo 2020-2, con el ánimo de intervenir a futuro dicha población mediante estrategias de promoción-prevención focalizadas

    Hidden MHC genetic diversity in the Iberian ibex (Capra pyrenaica)

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    [EN]Background: Defining hidden genetic diversity within species is of great significance when attempting to maintain the evolutionary potential of natural populations and conduct appropriate management. Our hypothesis is that isolated (and eventually small) wild animal populations hide unexpected genetic diversity due to their maintenance of ancient polymorphisms or introgressions. Results: We tested this hypothesis using the Iberian ibex (Capra pyrenaica) as an example. Previous studies based on large sample sizes taken from its principal populations have revealed that the Iberian ibex has a remarkably small MHC DRB1 diversity (only six remnant alleles) as a result of recent population bottlenecks and a marked demographic decline that has led to the extinction of two recognized subspecies. Extending on the geographic range to include non-studied isolated Iberian ibex populations, we sequenced a new MHC DRB1 in what seemed three small isolated populations in Southern Spain (n=132). The findings indicate a higher genetic diversity than previously reported in this important gene. The newly discovered allele, MHC DRB1*7, is identical to one reported in the domestic goat C. aegagrus hircus. Whether or not this is the result of ancient polymorphisms maintained by balancing selection or, alternatively, introgressions from domestic goats through hybridization needs to be clarified in future studies. However, hybridization between Iberian ibex and domestic goats has been reported in Spain and the fact that the newly discovered allele is only present in one of the small isolated populations and not in the others suggests introgression. The new discovered allele is not expected to increase fitness in C. pyrenaica since it generates the same protein as the existing MHC DRB1*6. Analysis of a microsatellite locus (OLADRB1) near the new MHC DRB1*7 gene reveals a linkage disequilibrium between these two loci. The allele OLADRB1, 187 bp in length, was unambiguously linked to the MHC DRB1*7 allele. This enabled us to perform a DRB-STR matching method for the recently discovered MHC allele. Conclusions: This finding is critical for the conservation of the Iberian ibex since it directly affects the identification of the units of this species that should be managed and conserved separately (Evolutionarily Significant Units).SIThis study was partially funded by the Consejería de Medio Ambiente of the Junta de Andalucía (projects 173/2009/M/00 and 03/15/M/00) and the Ministerio de Economía y Competitividad of the Spanish Government (projects CGL2012-40043-C02-01, CGL2012-40043-C02-02 and CGL2016-80543-P). The funding bodies did not contribute to the design of the study or collection, analysis and interpretation of data, or to the writing of the manuscript

    CA 15-3 prognostic biomarker in SARS-CoV-2 pneumonia.

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    The severity of lung involvement is the main prognostic factor in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Carbohydrate antigen 15-3 (CA 15-3), a marker of lung damage and fibrosis, could help predict the prognosis of SARS-CoV-2 pneumonia. This was a retrospective and observational study. CA 15-3 was analyzed in the blood samples of patients consecutively admitted for SARS-CoV-2 pneumonia and whose blood samples were available in the biobank. Other prognostic markers were also measured (interleukin 6 [IL6], C-reactive protein [CRP], D-dimer, troponin T, and NT-ProBNP). The occurrence of in-hospital complications was registered, including death, the need for medical intensive care, and oxygen therapy at discharge. In this study, 539 patients were recruited (54.9% men, mean age: 59.6 ± 16.4 years). At admission, the mean concentrations of CA 15-3 was 20.5 ± 15.8 U/mL, and the concentration was correlated with male sex, older age, and other severity markers of coronavirus disease of 2019 (COVID-19) (IL6, CRP, D-dimer, troponine T, and NT-ProBNP). CA 15-3 levels were higher in patients who died (n = 56, 10.4%) (35.33 ± 30.45 vs. 18.8 ± 12.11, p < 0.001), who required intensive medical support (n = 78, 14.4%; 31.17 ± 27.83 vs. 18.68 ± 11.83; p < 0.001), and who were discharged with supplemental oxygen (n = 64, 13.3%; 22.65 ± 14.41 vs. 18.2 ± 11.7; p = 0.011). Elevated CA 15-3 levels (above 34.5 U/mL) were a strong predictor of a complicated in-hospital course, in terms of a higher risk of death (adjusted odds ratio [OR] 3.74, 95% confidence interval [CI]: 1.22-11.9, p = 0.022) and need for intensive care (adjusted OR 4.56, 95% CI: 1.37-15.8) after adjusting for all other risk factors. The degree of lung damage and fibrosis evaluated in terms of CA 15-3 concentrations may allow early identification of the increased risk of complications in patients with SARS-CoV-2 pneumonia.S

    Toward integrated analysis of human impacts on forest biodiversity: lessons from Latin America.

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    Although sustainable forest management (SFM) has been widely adopted as a policy and management goal, high rates of forest loss and degradation are still occurring in many areas. Human activities such as logging, livestock husbandry, crop cultivation, infrastructural development, and use of fire are causing widespread loss of biodiversity, restricting progress toward SFM. In such situations, there is an urgent need for tools that can provide an integrated assessment of human impacts on forest biodiversity and that can support decision making related to forest use. This paper summarizes the experience gained by an international collaborative research effort spanning more than a decade, focusing on the tropical montane forests of Mexico and the temperate rain forests of southern South America, both of which are global conservation priorities. The lessons learned from this research are identified, specifically in relation to developing an integrated modeling framework for achieving SFM. Experience has highlighted a number of challenges that need to be overcome in such areas, including the lack of information regarding ecological processes and species characteristics and a lack of forest inventory data, which hinders model parameterization. Quantitative models are poorly developed for some ecological phenomena, such as edge effects and genetic diversity, limiting model integration. Establishment of participatory approaches to forest management is difficult, as a supportive institutional and policy environment is often lacking. However, experience to date suggests that the modeling toolkit approach suggested by Sturvetant et al. (2008) could be of value in such areas. Suggestions are made regarding desirable elements of such a toolkit to support participatory-research approaches in domains characterized by high uncertainty, including Bayesian Belief Networks, spatial multi-criteria analysis, and scenario planning.Most of the research described here was undertaken in three projects supported by the European Commission (INCO programme), namely SUCRE (ERBIC18CT970146), BIOCORES (ICA4- CT-2001-10095), and ReForLan (INCO-DEV-3 N° 032132), and three Darwin Initiative (DEFRA, UK Government) grants to the senior author. Additional funding was provided by a variety of sources within the partner countries. All sources of financial support are gratefully acknowledged
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