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Imagen de apoyo de Analysis of the Prevalence and Incidence of Cleft Lip and Palate in Colombia

Por: Herney Alonso; Guarnizo Peralta Rengifo Reina | Fecha: 2020

Abstract: Objective: To analyze the population prevalence and birth prevalence of oral clefts in Colombia from 2009 to 2017. Methods: A cross-sectional study using information from the National Administrative Records of Colombia. The data came from 2 types of administrative records (Surveillance System and the Individual Registry of Service Provision) and the oral health national survey. Population prevalence and birth prevalence by type of cleft lip and/or cleft (CL/P) ratios were calculated using Poisson distribution for count data and to assess stationary tests on time series (Dickey-Fuller) and (Phillips-Perron) was used. Results: Population prevalence in Colombia was 3.27 per 10 000 inhabitants (95% confidence interval [CI], 3.21-3.32) and birth prevalence was 6.0 per 10 000 live births (95% CI, 5.67-6.35). Bogot´a have the highest population prevalence with CL/P. In the analysis of trends for the prevalence proportion by type of clefts in newborn babies with cleft, it was observed that the highest proportion was for babies with CLP. Cleft lip (CL) has increased from 17.4% in 2014 to 34.2% in 2017, cleft palate (CP) has decreased from 32.9% to 20.2%; and CLP changed from 49.6% to 45.5% in the same period. Conclusions: The population prevalence was 3.27 per 10 000 inhabitants. Births prevalence was 6.0 per 10 000 live births, and Orinoquia and Amazonia have higher rates than the national average. The administrative registers are adequate systems to know the behavior of oral clefts. The CL/P had a nonstationary trend during the period 2014 to 2017.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros
Medicina

Imagen de apoyo de Population prevalence and trends of oral clefts in Colombia: analysis by departments

Por: Herney Alonso; Guarnizo Peralta Rengifo Reina | Fecha: 2021

Abstract: Objective: Determine the population prevalence and trends of cleft lip and / or palate (CL/P) by department for Colombia in the period 2009 - 2015. Methods: Prevalence study based on Individual Registry of Health Services in general population from 2009 to 2015. All people diagnosed with CL/P were included for all ages, type of diagnosis and any type of health services in the mentioned period. The prevalence rate was calculated by period and point for each year, for each department and according to the type of cleft. Stationarity on time series was evaluated using (Dickey-Fuller) and (Phillips-Perron), the trends and prevalence ratios were calculated using Poisson regression. Results: 15,225 people with CL/P were identified, where 53.3% were men. The national period prevalence of CL/P is 3.37 per 10 000 (IC95%: 3.3-3.4) with upward trend (PR = 1.34 95% CI: 1.0 - 1.8 p = 0.05) and non-stationary behavior. The national period prevalence of CL is 0.93 per 10 000, CP 1.17 per 10 000 and CLP 1.26 per 10 000, where CLP is sub classify into CLPu (0.83 per 10 000), and CLPb (0.43 per 10 000). At the departmental level, the highest CL/P prevalence is Guaviare (11.2 95% CI: 8.6 – 14.2), followed by Guainía (8.4 95% CI:5.4 – 12.2) and the lowest Quindío (0.49 95% CI: 0.3 – 0.7) Conclusions: In Colombia, the national period prevalence of CL/P is 3.37 per 10 000 with upward trend at national level indicates an increase on prevalence from 2009 to 2015.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros
Medicina

Imagen de apoyo de Impact of dimensionality on nowcasting seasonal influenza with environmental factors

Por: Stefany Brigetty; Miliou Guarnizo Peralta | Fecha: Ca. 2020

Abstract: Seasonal influenza is an infectious disease of multi-causal etiology and a major cause of mortality worldwide that has been associated with environmental factors. In the attempt to model and predict future outbreaks of seasonal influenza with multiple environmental factors, we face the challenge of increased dimensionality that makes the models more complex and unstable. In this paper, we propose a nowcasting and forecasting framework that compares the theoretical approaches of Single Environmental Factor and Multiple Environmental Factors. We introduce seven solutions to minimize the weaknesses associated with the increased dimensionality when predicting seasonal influenza activity levels using multiple environmental factors as external proxies. Our work provides evidence that using dimensionality reduction techniques as a strategy to combine multiple datasets improves seasonal influenza forecasting without the penalization of increased dimensionality.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros
Medicina

Imagen de apoyo de Recurring adaptive introgression of a supergene variant that determines social organization = Introgresión adaptativa recurrente de una variante de un supergen que determina la organización social

Por: Eckart; Pracana Stolle | Fecha: 2022

Abstract: Introgression has been proposed as an essential source of adaptive genetic variation. However, a key barrier to adaptive introgression is that recombination can break down combinations of alleles that underpin many traits. This barrier might be overcome in supergene regions, where suppressed recombination leads to joint inheritance across many loci. Here, we study the evolution of a large supergene region that determines a major social and ecological trait in Solenopsis fire ants: whether colonies have one queen or multiple queens. Using coalescent-based phylogenies built from the genomes of 365 haploid fire ant males, we show that the supergene variant responsible for multiple-queen colonies evolved in one species and repeatedly spread to other species through introgressive hybridization. This finding highlights how supergene architecture can enable a complex adaptive phenotype to recurrently permeate species boundaries.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Effects of Curing on Photosensitive Resins in SLA Additive Manufacturing

Por: Carmela; Civera Riccio | Fecha: 2021

Abstract: Different mechanical properties characterise the materials of 3D printed components, depending on the specific additive manufacturing (AM) process, its parameters, and the posttreatment adopted. Specifically, stereolithography (SLA) uses a photopolymerisation technique that creates solid components through selective solidification. In this study, 72 specimens were 3D printed using 12 commercial-grade methacrylate resins and tested under uniaxial tensile loads. The resin specimens were evaluated before and after curing. The recommended cure temperature and time were followed for all materials. The stress-strain curves measured during the testing campaign were evaluated in terms of maximum tensile strength, Young’s modulus, ductility, resilience, and toughness. The results reveal that the curing process increases the material stiffness and resistance to tensile loads. However, it was found that the curing process generally reduces the plasticity of the resins, causing a more or less marked brittle behaviour. This represents a potential limitation to the use of SLA 3D printing for structural elements which require some plasticity to avoid dangerous sudden failures.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Effects of the Manufacturing Methods on the Mechanical Properties of a Medical-Grade Copolymer Poly(L-lactide-co-D,L-lactide) and Poly(L-lactide-co-ε-caprolactone) Blend

Por: Mariana; Civera Rodríguez Reinoso | Fecha: 2021

Abstract: Biocompatible and biodegradable polymers represent the future in the manufacturing of medical implantable solutions. As of today, these are generally manufactured with metallic components which cannot be naturally absorbed within the human body. This requires performing an additional surgical procedure to remove the remnants after complete rehabilitation or to leave the devices in situ indefinitely. Nevertheless, the biomaterials used for this purpose must satisfy well-defined mechanical requirements. These are difficult to ascertain at the design phase since they depend not only on their physicochemical properties but also on the specific manufacturing methods used for the target application. Therefore, this research was focused on establishing the effects of the manufacturing methods on both the mechanical properties and the thermal behavior of a medical-grade copolymer blend. Specifically, Injection and Compression Molding were considered. A Poly(L-lactide-co-D,L-lactide)/Poly(L-lactide-co-#-caprolactone) blend was considered for this investigation, with a ratio of 50/50 (w/w), aimed at the manufacturing of implantable devices for tendon repair. Interesting results were obtained.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Larger, more connected societies of ants have a higher prevalence of viruses = Las sociedades de hormigas más grandes y conectadas tienen una mayor prevalencia de virus

Por: Anindita; Gray León Brahma | Fecha: 2021

Abstract: The benefits of cooperative living for foraging, nesting, defence and buffering envi- ronmental challenges lead animals with the most highly social lifestyles to dominate many ecosystems. However, living in larger, more highly connected groups should also increase the risks of pathogen exposure and transmission. While over long timescales selective responses could buffer the impacts of potential higher pathogen prevalence, similar processes are unlikely over short timescales. The red fire ant Solenopsis in- victa is ideal for measuring the effects of group size on pathogen prevalence because two types of society coexist in this species: smaller single-nest single-queen colonies that are highly aggressive to their neighbours and larger multiple-queen colonies that exchange resources with neighbouring nests. We compare the presence of viruses between these two colony types using metagenomic sequence classification of RNA- sequencing reads. We find that queens from multiple-queen colonies have 8.3-times higher viral load and 1.5-times higher viral diversity than queens from single-queen colonies. This finding characterizes a rarely considered cost of transitions to more highly social living. Furthermore, our results show that highly social invertebrates can harbour many viruses.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Music Emotion Recognition: toward new, robust standards in personalized and context-sensitive applications = Reconocimiento de emociones en la música: Hacia estándares nuevos y robustos para aplicaciones personalizadas y sensibles al contexto

Por: Juan Sebastián; Cano Gómez Cañón | Fecha: 2021

Abstract: In this paper we present a review of the challenges and limitations of Music Emotion Recognition (MER), an interdisciplinary research area addressing the characterization of music in terms of emotion. It analyzes music in order to computationally predict the emotions perceived by or induced to a listener. Our aims are: (1) to provide insights on the typical approaches currently used in the MER workflow, and (2) hint at how previous research directs to specific future directions. We propose a new user-centric conceptualization framework for MER, highlighting where future researchers should focus efforts: (1) open data and experimental reproducibility, (2) inherent subjectivity of concepts and annotations, (3) model explainability and interpretability, (4) cultural and contextual relevance, and (5) ethical implications for MER applications. En este paper presentamos una revisión de los retos y limitaciones de Music Emotion Recognition (MER), una área de investigación interdisciplinar dirigida a caracterizar la música en términos de emociones. Se enfoca en analizar música para predecir computacionalmente las emociones percibidas o inducidas a un oyente. Nuestros objetivos son: (1) ofrecer conocimientos sobre los enfoques típicos del flujo de trabajo de MER, y (2) insinuar como la investigación pasada apunta hacia nuevas direcciones específicas. Proponemos una nueva estructura de conceptualización centrada en el usuario, enfatizando las direcciones donde futuros investigadores deberían enfocar sus esfuerzos: (1) datos libres y reproducibilidad experimental, (2) subjetividad inherente de conceptos y anotaciones, (3) interpretabilidad y explicabilidad de los modelos, (4) relevancia cultural y contextual y (5) implicaciones éticas de aplicaciones de MER. Debido a la naturaleza de la publicación y el impacto de la revista, sólo puedo compartir la versión aceptada.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de The Evolution of Global Instant Payment Infrastructure

Por: Juan Camilo; Hedman Giraldo Mora | Fecha: 2020

Abstract: Global instant payment and its underlying infrastructure evolution are commonly referred to as fragmentation, with the proliferation of local instant payment systems, or consolidation, with few global instant payment systems prevailing. Even though these evolution views and related management practices are valuable, they emphasize linear and conflict-oriented evolution perspectives that undermine the possibility of progressive fragmentation and consolidation. Conversely, this paper introduces three mechanisms, transactional, modular, and institutional, as well as three related qualities, service layers, service granularity, and service integration, that characterize the evolution of global instant payment infrastructure. Drawing upon four global payment case studies, the paper illustrates evolution patterns that emerge with the mutual and reinforcing influence between these evolution mechanisms and qualities. We find that the evolution of global instant payment infrastructure is taking place with the creation, and integration, of context-specific payment services, and the reduction of layers in payment services. This perspective revisits the fragmentation vis-à-vis consolidation arguments in favor of evolution patterns, which account for progressive fragmentation and consolidation of global instant payment infrastructure.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Análisis comparativo de modelos 1d, 2d y 3d en la simulación hidráulica del meandro del río Magdalena en La Dorada (Caldas – Colombia)

Por: Freddy Leonardo; Yara Amaya Franco Idarraga | Fecha: 2021

Resumen: El Magdalena es el río más importante del centro de Colombia, con una elevada dinámica e importantes cambios a través del tiempo. En un cerrado meandro de aproximadamente 8 km de longitud, se ubica La Dorada (Caldas - Colombia); población que, por su ubicación, extensión, características geográficas, sociales y turísticas está siendo foco de desarrollo económico e impulso del departamento, la región y el país en general. No obstante –al estar a orilla de un gran río– desde su fundación la ciudad ha vivido recurrentes eventos de inundación que han afectado un gran número de habitantes. Razón por la cual, este estudio presenta el análisis de los niveles del río, sus velocidades superficiales y las áreas de inundación; como las más importantes variables en las singulares condiciones de flujo de un acentuado meandro, mediante la utilización de tres softwares de modelación hidráulica: HEC-RAS, IBER y FLOW-3D (1D, 2D y 3D respectivamente). Con los cuales, calculando bajo períodos de retorno de 10 a 500 años, fue posible encontrar similitudes y diferencias entre sus resultados y definir con gran aproximación la verdadera dimensión de las anegaciones en el casco urbano.

Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos

Temas:
Otros