Viral quasispecies profiles as the result of the interplay of competition and cooperation

Viral quasispecies can be regarded as a swarm of genetically related mutants or a quasispecies (QS). A common formalism to approach QS is the replicator-mutator equation (RME). However, a problem with the RME is how to quantify the interaction coefficients between viral variants. Here, this is addressed by adopting an ecological perspective and resorting to the niche theory of competing communities, which assumes that the utilization of resources primarily determines ecological segregation between competing individuals (the different viral variants that constitute the QS). Using this novel combination of RME plus the ecological concept of niche overlapping, for describing QS, we explore the population distributions of viral variants that emerge, as well as the corresponding dynamics. We observe that the population distribution requires very long transients both to A) reach equilibrium and B) to show a clear dominating master sequence. Based on different independent and recent experimental evidence, we find that when some cooperation or facilitation between variants is included in appropriate doses we can solve both A) and B). We show that a useful quantity to calibrate the degree of cooperation is the Shannon entropy. Therefore, in order to get a typical quasispecies profile, it seems that pure competition is not enough. Rather, some degree of cooperation among viral variants is needed. This has several biological implications that might contribute to shed light on the mechanisms operating in QS dynamics and to understand the QS as a whole entity.Comment: 23 pages, 5 figure

A Comparative Genomics Study of Human and Chimpanzee Evolution: Natural Selection, Function, and Disease

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 19-06-0

A critique of contemporary artificial intelligence art: Who is Edmond de Belamy?

Edmond de Belamy is a 2018 painting made by french collective Obvious, created using a type of Artificial Intelligence algorithms called Generative Adversarial Networks, which was sold at Christie's auction house in New York for $432,500. This historic event -the so-called auction of the "first artwork made by an AI" raises 3 interesting questions about authorship, originality, and the arts as a space for scientific inquiry. While some think that the current deployment of Machine Learning algorithms and Artificial Intelligence techniques that we are seeing in the art world today may be seen as the ultimate "Gesamtkunstwerk" or total artwork, other points of view express that not only we need this type of cultural artifacts as a critique of industrialized use of Artificial Intelligence, but also a strict criteria has to be delimited in order to review contemporary art made with Machine Learning techniques

La madre soltera frente a la sociedad

La moral colectiva de los pueblos o grupos sociales, a medida que éstos avanzan en la comprensión científica y racional de los fenómenos diversos, es decir, en su culturización, pierde su rigidez intolerante e irracional y se enriquece abarcando actitudes, ideologías, comportamientos, etcétera, que difieren de la norma imperante, sin ser por ello menos valiosos ni respetables. Pero, mientras en algunos campos esta moral social evoluciona al compás del tiempo, en otros (especialmente en los relacionados con la sexualidad y concretamente con la femenina) conserva restos arcaicos que crean desfases y desniveles en lo que había de ser un desarrollo armonioso de la mentalidad colectiva y del pensar y proceder de sus componentes. Dentro de las lagunas o marginaciones ejercidas sobre grupos determinados, hemos estudiado el caso específico de las madres solteras y del montaje mental y real que existe: en su contra. Hemos actuado a dos niveles: uno personal, entrevistando a madres solteras, individualmente; y otro social, visitando los centros de asistencia creados para ellas. Entre ambos, hemos seguido los pasos de una madre soltera, desde su embarazo hasta su lucha diaria por integrarse con su hijo en la sociedad. También hemos incidido en el aspecto judicial. Hubiéramos querido completarlo con un sondeo en empresas (a nivel de colocación), colegios (en cuanto a dificultades para ingresar al niño) y finalmente en la calle (mercados, bares, espectáculos). No fue posible por falta de tiempo, pero los resultados obtenidos hablan por sí solos y creemos que reflejan la opinión general y la situación actual con bastante fidelidad

Music and Mathematics: some relations and a teaching proposal with students of first year of Scientific Baccalaureate

RESUMEN En el presente Trabajo de Fin de Máster (TFM) se realiza un breve recorrido por las estrechas relaciones existentes entre el arte y la ciencia y más en particular, entre la música y las matemáticas. Además, basándose en un estudio que relaciona la música flamenca y las matemáticas, en el que se analizan diferentes tipos de cante flamenco desde una perspectiva matemática, en este trabajo se describe una propuesta didáctica que relaciona los patrones rítmicos de dos canciones de diferentes estilos de música popular con ciertos elementos geométricos. Después, se detallan los hechos acaecidos en la implementación de dicha propuesta con un grupo de alumnos de 1º de Bachillerato de Ciencias, y, finalmente, se realiza un análisis de los resultados obtenidos a través de un cuestionario que recoge diversas actividades relacionadas con la propuesta, el cual cumplimentaron dichos alumnosABSTRACT In the present Master’s Thesis, a small tour through the close relations existing, between art and science and, more in particular, between music and mathematics, is reported. Moreover, based in a study that describes a special relationship between flamenco music and mathematics, in which different types of flamenco singing are analyzed from a mathematical point of view, in this work a teaching proposal that relates the rhythmic patterns of two popular music songs of different styles with certain geometric elements is described. Then, the implementation of this teaching proposal with a group of students of first year of Scientific Baccalaureate is detailed, and, finally, it is made an analysis of the results obtained through a questionnaire that contains some tasks about this proposal, which these students had completed.Máster en Formación del Profesorado de Educación Secundari

Genetic Characterization of a Pigeon Paramyxovirus Type 1 Isolated from Columba livia in Uruguay

The isolation and molecular characterization of pigeon paramyxovirus type 1 (PPMV-1) from a sick racing pigeon in Uruguay is reported for the first time. Hemagglutination inhibition (HI) tests were performed to detect antibodies against avian paramyxovirus serotype 1 (APMV-1), and a HI titer of 1/32 was obtained. Tracheal and cloacal swabs were processed by real-time reverse transcriptionpolymerase chain reaction (rRT-PCR) with the use of the National Veterinary Services LaboratoryU.S. Department of Agriculture validated matrix (M) gene assay and were positive for APMV-1. Viral isolation in embryonated chicken eggs confirmed the molecular detection of the isolate. A fragment corresponding to the 3' region of the fusion (F) protein gene was amplified by RT-PCR, and subsequently sequenced. The deduced amino acid sequence at the F protein cleavage site displayed the motif 112RRQKR/F 117. Phylogenetic analysis of this part of the genome allowed the isolated virus to be grouped in the lineage VIb/4b, which suggests that it shares the same ecologic niche with other PPMV-1 that were found in the region, and it is not imported as other European or North American viruses.Fil: Castro, E. R.. No especifíca;Fil: Zanetti, Flavia Adriana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arbiza, Juan. Universidad de la Republica; Urugua

Positive Selection, Relaxation, and Acceleration in the Evolution of the Human and Chimp Genome

For years evolutionary biologists have been interested in searching for the genetic bases underlying humanness. Recent efforts at a large or a complete genomic scale have been conducted to search for positively selected genes in human and in chimp. However, recently developed methods allowing for a more sensitive and controlled approach in the detection of positive selection can be employed. Here, using 13,198 genes, we have deduced the sets of genes involved in rate acceleration, positive selection, and relaxation of selective constraints in human, in chimp, and in their ancestral lineage since the divergence from murids. Significant deviations from the strict molecular clock were observed in 469 human and in 651 chimp genes. The more stringent branch-site test of positive selection detected 108 human and 577 chimp positively selected genes. An important proportion of the positively selected genes did not show a significant acceleration in rates, and similarly, many of the accelerated genes did not show significant signals of positive selection. Functional differentiation of genes under rate acceleration, positive selection, and relaxation was not statistically significant between human and chimp with the exception of terms related to G-protein coupled receptors and sensory perception. Both of these were over-represented under relaxation in human in relation to chimp. Comparing differences between derived and ancestral lineages, a more conspicuous change in trends seems to have favored positive selection in the human lineage. Since most of the positively selected genes are different under the same functional categories between these species, we suggest that the individual roles of the alternative positively selected genes may be an important factor underlying biological differences between these species

Planificación estratégica de recursos humanos para una consultora de servicios profesionales

Incluye BibliografíaEl propósito de este trabajo es analizar el funcionamiento de la Consultora A&S desde la perspectiva de la gestión de los recursos humanos que la componen, de forma de generar una mirada integral de dicha gestión y visibilidad de su incidencia en la competitividad del negocio

Detection and genotyping of equid herpesvirus 1 in Uruguay

Infection with equid alphaherpesvirus 1 (EHV-1) causes respiratory disease, abortion and neurological disorders in horses. Molecular epidemiology studies have demonstrated that a single nucleotide polymorphism (A2254/G2254) in the genome region of open reading frame 30 which results in an amino acid variation (N752/D752) of the EHV-1 DNA polymerase, is significantly associated with the neuropathogenic potential of naturally occurring strains. In recent years, an increase in the number of cases of equine neurological disease caused by neuropathogenic variants of EHV-1 has been observed in numerous countries. The purpose of this study was to detect the presence of the viral genome of EHV-1 and equid herpesvirus 4 (EHV-4) in the bronchopulmonary lymph nodes of 47 horses from various locations in Uruguay, obtained from a slaughterhouse, and to determine whether the EHV-1 genomes possessed the mutation associated with neuropathogenesis (G2254/D752). The genes encoding glycoprotein H (gH) of EHV-1 and glycoprotein B (gB) of EHV-4 were amplified by a semi-nested polymerase chain reaction. Of the samples analysed, 28% and 6% of lymph nodes contained the genes for gH and gB, respectively. The viral DNA olymerase gene was amplified and sequenced. Twelve of the 13 genomes sequenced presented the nucleotide G2254, while the remaining 1 showed both nucleotides, A2254 and G2254. The results confirm the presence of EHV-1 in Uruguay. Furthermore, there is evidence for the first time of the detection of EHV- 4, and high-frequency detection of the neuropathogenic variant (G2254/D752) of EHV-1 in Uruguay. These findings provide new insights into the epidemiological situation of EHV-1 and EHV-4 in that country