329 research outputs found
The replicator coalescent
We consider a stochastic model, called the replicator coalescent, describing
a system of blocks of different types which undergo pairwise mergers at
rates depending on the block types: with rate blocks of type and
merge, resulting in a single block of type . The replicator coalescent
can be seen as generalisation of Kingman's coalescent death chain in a
multi-type setting, although without an underpinning exchangeable partition
structure. The name is derived from a remarkable connection we uncover between
the instantaneous dynamics of this multi-type coalescent when issued from an
arbitrarily large number of blocks, and the so-called replicator equations from
evolutionary game theory. By dilating time arbitrarily close to zero, we see
that initially, on coming down from infinity, the replicator coalescent behaves
like the solution to a certain replicator equation. Thereafter, stochastic
effects are felt and the process evolves more in the spirit of a multi-type
death chain.Comment: 1 figur
Rainbow polygons for colored point sets in the plane
Given a colored point set in the plane, a perfect rainbow polygon is a simple polygon that contains exactly one point of each color, either in its interior or on its boundary. Let rb-index(S) denote the smallest size of a perfect rainbow polygon for a colored point set S, and let rb-index(k) be the maximum of rb-index(S) over all k-colored point sets in general position; that is, every k-colored point set S has a perfect rainbow polygon with at most rb-index(k) vertices. In this paper, we determine the values of rb-index(k) up to k=7, which is the first case where rb-index(k)¿k, and we prove that for k=5, [Formula presented] Furthermore, for a k-colored set of n points in the plane in general position, a perfect rainbow polygon with at most [Formula presented] vertices can be computed in O(nlogn) time. © 2021 Elsevier B.V
Estimación de la carga global de enfermedad en Colombia 2012: nuevos aspectos metodológicos
La nueva metodología de carga global de enfermedad (GBD, 2010) resulta difícil de reproducir completamente en Colombia. En este trabajo se presentan los resultados de utilización parcial de esta metodología para estimar los años perdidos por muerte prematura (APMP) y los vividos con discapacidad (AVD). La redistribución de códigos inútiles produce incrementos importantes en las causas de muerte, que es preferible a un análisis de causas de muerte con un 15,6 % de códigos inútiles que aportarían poca o ninguna información estadística. La cardiopatía isquémica, eventos cerebrovasculares y la cardiopatía hipertensiva causan el mayor riesgo de mortalidad (164,2 muertes por 100 000). Las agresiones por arma de fuego y objeto cortante, las lesiones auto-infligidasy las provocadas por vehículos de tres y cuatro ruedas, causan el mayor riesgo de APMP (34,3 APMP por 1000). Enfermedades de piel como la dermatitis, eritemas, la pediculosis y la pitiriasis, causan el mayor riesgo de AVD (51,3 AVD por 1000). Este grupo de enfermedades de la piel también resultan la principal causa de AVISAs Totales (51,4 AVISAs Totales por 1000). Los departamentos con las tasas más elevadas de mortalidad y APMP para las causas del grupo I (enfermedades transmisibles) son Guainía, Amazonas, Vaupés, Cauca, Vichada, Putumayo, Nariño, Chocó, Córdoba, La Guajira, Guaviare y Caquetá, que están entre los de más baja cobertura de la mortalidad.The new methodology applying for burden of disease study (GBD 2010) is difficult tocompletely reproduce in Colombia. This paper presents the results of partial use of this methodology to estimate the components years lost due to premature death (YLLs) and lived with disability (YLDs). Redistribution of useless codes produces significant increases in some causes of death, which are preferable to deal with an analysis of causes of death with 15,6 % of useless codes that would provide little or no statistical information. Ischemic heart disease, cerebrovascular and hypertensive heart disease events cause the highest risk of mortality rate (164,2 per 100,000). Assaults by firearms and sharp objects, self-inflicted injuries and those caused by motorcycles and four-wheeled vehicles on the road, are the first cause of YLLs per 1000 (34,3). Skin diseases such as dermatitis, erythemas, burns on exposure to sunlight, pediculosis and pityriasis, cause the greatest risk of YLDs per 1000 (51,3). This group of skin diseases are also the leading cause of DALYs per 1000 (51,4). The departments with the highest rates of mortality and YLLs for Group I (communicable diseases) are Guainía, Amazonas, Vaupés, Cauca, Vichada, Putumayo, Nariño, Chocó, Cordoba, La Guajira, Guaviare y Caquetá and with the lower mortality coverage
Developing markets? Understanding the role of markets and development at the intersection of macromarketing and transformative consumer research (TCR)
Situated at the intersection of markets and development, this commentary aims to promote a cross-fertilization of macromarketing and Transformative Consumer Research (TCR) that directs attention to the sociocultural context and situational embeddedness of consumer experience and well-being, while acknowledging complex, systemic interdependencies between markets, marketing, and society. Based on a critical review of the meaning of development and an interrogation of various developmental discourses, the authors develop a conceptual framework that brings together issues of development, well-being, and social inequalities. We suggest that these issues are better understood and addressed when examined via grounded investigations of the role of markets in shaping the management of resources, consumer agency, power inequalities and ethics. The use of markets as units of analysis may lead to further cross-fertilizations of TCR and macromarketing and to more comprehensive theorizing and transformational impact. Two empirical cases are provided to illustrate our framework
Prognostic stratification improvement by integrating ID1/ID3/IGJ gene expression signature and immunophenotypic profile in adult patients with B-ALL
Characteristics of pronostic groups according to EuroFlow immunophenotype. (TIFF 1364 kb
ANALISIS DE LAS RESPUESTAS FISIOLÓGICAS QUE SE GENERAN EN UN PACIENTE CON PANCREATITIS AGUDA: UN CASO DE ESTUDIO.
Se presenta el caso de una paciente de 42 años de edad Objetivo: Valorar las respuestas humanas fisiológicas de la pancreatitis aguda a través de los dominios NANDA, que permita establecer el plan de cuidados determinado para el cliente Metodología: abordaje cualitativo observacional descriptivo, permitiendo justificar la sintomatología presente en la paciente con la que se desarrolla en la evolución de la patología; siendo esta metodología útil para verificar y desarrollar el proceso de diagnostico a la muestra incluye una paciente, del servicio hospitalario de medicina interna de la ESE San Juan de Dios, Pamplona Resultados: El paciente siente satisfacción cuando percibe la vocación y la voluntad de servicio de la enfermera. La satisfacción por buena atención se concibe como un campo de aceptación limitada. Conclusión: estos hallazgos indican la necesidad de valorar la incertidumbre e identificar factores relacionados como capacidades cognitivas, y fuentes de estructura que inciden positiva o negativamente en la aparición de la misma
Papilledema as an initial fi nding in venous sinus thrombosis in a child. Case report and literature review
Introducción: La trombosis de senos venosos (TSV) en niños, sin factores
de riesgo es una patología rara pero potencialmente fatal. La cefalea es el síntoma
principal y muy pocos pacientes se presentan sin este. El papiledema como
hallazgo inicial se presenta sólo en el 9% de los pacientes. Presentamos el caso de
una menor de 13 años, sin factores de riesgo para TSV, cuya manifestación inicial
fue el papiledema en ausencia de cefalea.
Objetivo: Describir el caso clínico de una paciente menor de edad sin
comorbilidades, factores de riesgo ni cefalea, con papiledema como única
manifestación de TSV.
Diseño de estudio: Reporte de caso. Resumen del caso: Menor de 13 años, sin antecedentes, con cuadro clínico
de 12 horas de evolución de dolor en ojo derecho de instauración progresiva,
tipo punzada, asociado a visión doble y un episodio emético. Al examen físico
con agudeza visual (AV) 20/20 en ambos ojos, con papiledema; sin hallazgos
positivos al examen neurológico ni en otros sistemas.
Conclusión: La TSV en pacientes pediátricos sin factores de riesgo ni cefalea
es rara. El papiledema es uno de los hallazgos principales de esta patología y en
pocas ocasiones es la manifestación inicial. Es importante conocer los síntomas
y signos oft almológicos de la TSV, ya que pueden ser el único hallazgo en esta
patología.Background: Venous sinus thrombosis (VST) in children, without risk
factors, is a rare but potentially fatal pathology. Headache is the main symptom
and only few patients present without it. Papilledema as an initial fi nding occurs
only in 9% of patients. We present the case of a 13 years old girl, without risk factors
for VST, with papilledema as initial manifestation in the absence of headache.
Objective: To describe a clinical case of with venous sinus thrombosis
without comorbidities or risk factors, who had papilledema as fi rst symptom.
Study design: Case report and literature review
Case summary: 13 years old girl, without medical history, with a clinical
picture of 12 hours of right eye progressive pain, prick type, associated with
double vision and an emetic episode. Physical examination with visual acuity (VA)
20/20 in both eyes and papilledema; without positive fi ndings in the neurological
examination or in other systems.
Conclusion: Venous sinus thrombosis in pediatric patients without risk
factors or headache is rare. Papilledema is one of the main fi ndings of this
pathology and in few cases it is the initial manifestation. It is important to know
the symptoms and ophthalmological signs of VST because it could be the only
fi nding in this pathology
La enfermedad de hígado graso no alcohólica y su asociación con obesidad y estrés oxidativo hepático
ResumenLa enfermedad de hígado graso no alcohólico (EHGNA) es una entidad clínica-histológica de etiológia multifactorial cuyos mecanismos aún no se conocen totalmente . Existen evidencias de aumento del estrés oxidativo hepático en pacientes con EHGNA. El objetivo del estudio fue relacionar parámetros hepáticos y plasmáticos asociados al estrés oxidativo con la histológia hepática de pacientes con EHGNA.[Carrasco RA, Castillo RL, Huerta PA, Thieleman L. La enfermedad de hígado graso no alcohólica y su asociación con obesidad y estrés oxidativo hepático. MedUNAB 2003; 6(16):15-20].Palabras clave: hígado, estrés oxidativo, oxidación de proteínas, capacidad antioxidante del plasma
Harvest of Endangered Sideneck River Turtles (Podocnemis spp.) in the Middle Orinoco, Venezuela
We quantified illegal and unmonitored harvest of three endangered sideneck turtles (Podocnemis spp.) by examining discarded turtle shells in 29 riverine communities both up-and down-river from the Arrau Turtle Wildlife Refuge in the Middle Orinoco, Venezuela. We compared harvested turtle sizes to those captured during in-water research surveys to determine harvest selectivity. We found fresh sideneck turtle shells in most communities visited; carapaces and plastrons from P. expansa were the most abundant despite their protected status. Turtle harvest was skewed toward females in all species, and toward juvenile P. expansa and adult P. unifilis and P. vogli. Considering historical accounts of widespread turtle husbandry in the area, Podocnemis spp. life history, and population recovery for these species in community-based conservation programs elsewhere in South America, we recommend community-managed captive breeding of faster-maturing P. unifilis and P. vogli to satisfy turtle consumption needs. These measures, along with improved nesting-beach protection, may allow recovery of populations of P. expansa and make possible their legal subsistence harvest in the future. P ROPER management of exploited wildlife for sustained harvest, maintenance, or recovery requires not only knowledge of the demography and life history of a species but also a detailed understanding of the type of harvest they are experiencing Turtles have long been an important food resource for humans, but human population growth, enhanced harvest methods, and cultural merging have led to overexploitation of many turtle specie
Assessing the genetic diversity of farmed and wild Rufiji tilapia (Oreochromis urolepis urolepis) populations using ddRAD sequencing
Rufiji tilapia (Oreochromis urolepis urolepis) is an endemic cichlid in Tanzania. In addition to its importance for biodiversity conservation, Rufiji tilapia is also attractive for farming due to its high growth rate, salinity tolerance, and the production of all-male hybrids when crossed with Nile tilapia (Oreochromis niloticus). The aim of the current study was to assess the genetic diversity and population structure of both wild and farmed Rufiji tilapia populations in order to inform conservation and aquaculture practices. Double-digest restriction-site-associated DNA (ddRAD) libraries were constructed from 195 animals originating from eight wild (Nyamisati, Utete, Mansi, Mindu, Wami, Ruaha, Kibasira, and Kilola) and two farmed (Bwawani and Chemchem) populations. The identified single nucleotide polymorphisms (SNPs;n = 2,182) were used to investigate the genetic variation within and among the studied populations. Genetic distance estimates (F-st) were low among populations from neighboring locations, with the exception of Utete and Chemchem populations (F-st = 0.34). Isolation-by-distance (IBD) analysis among the wild populations did not detect any significant correlation signal (r = .05;p-value = .4) between the genetic distance and the sampling (Euclidean distance) locations. Population structure and putative ancestry were further investigated using both Bayesian (Structure) and multivariate approaches (discriminant analysis of principal components). Both analysis indicated the existence of three distinct genetic clusters. Two cross-validation scenarios were conducted in order to test the efficiency of the SNP dataset for discriminating between farmed and wild animals or predicting the population of origin. Approximately 95% of the test dataset was correctly classified in the first scenario, while in the case of predicting for the population of origin 68% of the test dataset was correctly classified. Overall, our results provide novel insights regarding the population structure of Rufiji tilapia and a new database of informative SNP markers for both conservation management and aquaculture activities
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