Bayesian analysis of the astrobiological implications of life's early emergence on Earth

Life arose on Earth sometime in the first few hundred million years after the young planet had cooled to the point that it could support water-based organisms on its surface. The early emergence of life on Earth has been taken as evidence that the probability of abiogenesis is high, if starting from young-Earth-like conditions. We revisit this argument quantitatively in a Bayesian statistical framework. By constructing a simple model of the probability of abiogenesis, we calculate a Bayesian estimate of its posterior probability, given the data that life emerged fairly early in Earth's history and that, billions of years later, curious creatures noted this fact and considered its implications. We find that, given only this very limited empirical information, the choice of Bayesian prior for the abiogenesis probability parameter has a dominant influence on the computed posterior probability. Although terrestrial life's early emergence provides evidence that life might be common in the Universe if early-Earth-like conditions are, the evidence is inconclusive and indeed is consistent with an arbitrarily low intrinsic probability of abiogenesis for plausible uninformative priors. Finding a single case of life arising independently of our lineage (on Earth, elsewhere in the Solar System, or on an extrasolar planet) would provide much stronger evidence that abiogenesis is not extremely rare in the Universe.Comment: updated acknowledgement

Should the teaching of biological evolution include the origin of life?

The development of mainstream research on the origin of life as an outcome of Darwinian evolution is discussed. It is argued that prebiotic evolution and the origin of life should not be excluded from the syllabus and should be part of classes on biological evolution, and that the transition from non-living to living matter is best understood when seen as part of evolutionary biology. The wide acceptance of evolutionary approaches to the study of the emergence of life in European and Latin American countries is discussed

Mechanics of milling 48-2-2 gamma titanium aluminide

Accurate and fast prediction of cutting forces is important in high-performance cutting in the aerospace industry. Gamma titanium aluminide (gamma-TiAl) is a material of choice for aerospace and automotive applications due to its superior thermo-mechanical properties. Nevertheless, it is a difficult to machine material. This article presents the prediction of cutting forces for Ti-48Al-2Cr-2Nb (48-2-2) gamma-TiAl in milling process using orthogonal to oblique transformation technique. The novelty of this paper lies in reporting the orthogonal database of 48-2-2 gamma-TiAl. Fundamental cutting parameters such as shear stress, friction angle and shear angle are calculated based on experimental measurements. Friction coefficients are identified for two different coating conditions which are AlTiN, and AlCrN on carbide tools. Predicted results are validated with the experimental cutting forces during end milling and ball-end milling operations for different cutting conditions. The simulated results showed good agreement with the experimental results, which confirms the validity of the force modelWOS:000568177300002Scopus - Affiliation ID: 60105072Science Citation Index ExpandedQ2ArticleUluslararası işbirliği ile yapılan - EVETAğustos2020YÖK - 2019-2

Prevalence, concordance and determinants of human papillomavirus infection among heterosexual partners in a rural region in central Mexico

Background: Although human papillomavirus (HPV) infection in heterosexual couples has been sparsely studied, it is relevant to understand disease burden and transmission mechanisms. The present study determined the prevalence and concordance of type-specific HPV infection as well as the determinants of infection in heterosexual couples in a rural area of Mexico. Methods: A cross-sectional study was conducted in 504 clinically healthy heterosexual couples from four municipalities in the State of Mexico, Mexico. HPV testing was performed using biotinylated L1 consensus primers and reverse line blot in cervical samples from women and in genital samples from men. Thirty-seven HPV types were detected, including high-risk oncogenic types and low-risk types. Multivariate logistic regression models were utilized to evaluate factors associated with HPV. Results: The prevalence of HPV infection was 20.5% in external male genitals and 13.7% in cervical samples. In 504 sexual couples participating in the study, concordance of HPV status was 79%; 34 partners (6.7%) were concurrently infected, and 21 out of 34 partners where both were HPV positive (61.8%) showed concordance for one or more HPV types. The principal risk factor associated with HPV DNA detection in men as well as women was the presence of HPV DNA in the respective regular sexual partner (OR = 5.15, 95% CI 3.01-8.82). In men, having a history of 10 or more sexual partners over their lifetime (OR 2.5, 95% CI 1.3 - 4.8) and having had sexual relations with prostitutes (OR 1.7, 95% CI 1.01 - 2.8) increased the likelihood of detecting HPV DNA. Conclusions: In heterosexual couples in rural regions in Mexico, the prevalence of HPV infection and type-specific concordance is high. High-risk sexual behaviors are strong determinants of HPV infection in men

Derechos humanos, paz y posconflicto en Colombia

197 p.Es relevante mencionar que este espacio académico se genera a partir del trabajo de investigación desarrollado por el grupo Personas, Instituciones y Exigencias de Justicia”, del Centro de Investigaciones Sociojurídicas la Facultad de Derecho de la Universidad Católica de Colombia, y está soportado en el trabajo investigativo de los autores de la obra que aquí se compila. El objetivo principal de este libro ha sido propiciar la investigación generadora de reflexiones de expertos, profesores e investigadores nacionales e internacionales en el área de los derechos humanos y del derecho internacional humanitario en torno a temáticas actuales y trascendentales para el país, derivadas del proceso de paz que adelanta el actual Gobierno colombiano con la guerrilla de las Fuerzas Armadas Revolucionarias de Colombia (FARC-EP) y sus consecuencias posteriores en el marco de lo que ha dado en llamarse el posconflicto. La primera parte del libro ha sido construida en clave comparada, partiendo de la consideración de la búsqueda de experiencias a soluciones políticas de conflictos armados que en otras latitudes han hecho historia sobre lo que significa el tránsito hacia la paz. Por ello, con la intención de conocer de primera mano los resultados y los pormenores que rodearon esos acuerdos de paz, así como el respeto posterior a lo firmado y las condiciones necesarias para que tales acuerdos fuesen realidad, investigadores expertos fueron invitados a reflexionar en visión comparada sobre el conflicto colombiano. Como resultado de esas reflexiones, el libro cuenta con un estudio de experiencias en los posconflictos de El Salvador, Guatemala y México, considerando también los cambios constitucionales que siguieron a los Acuerdos de Dayton que pusieron fin al conflicto en Bosnia-Herzegovina. El caso de Sudáfrica constituye una de las experiencias más exitosas en la resolución de antiguos conflictos, por lo que dicho caso ocupa un estudio particular de las experiencias analizadas en la obra.Prólogo Introducción Parte I. Análisis comparado Capítulo 1. Los procesos de paz en El Salvador, Guatemala y México: una visión comparada Capítulo 2. Les accords de paix de Dayton: quel constat? Capítulo 3. Proceso de paz en sudáfrica: ¿algunas lecciones para Colombia? Parte II. Reflexiones sobre el conflicto colombiano Capítulo 4. Sobre la situación de graves violaciones de derechos humanos y del derecho internacional humanitario en contra de las mujeres en el conflicto armado colombiano Capítulo 5. La protección jurídica para los niños en el conflicto armado colombiano: de la declaración de Ginebra al Protocolo Facultativo relativo a la Participación de Niños en los Conflictos Armados - Estándares internacionales para tener en cuenta en el proceso de paz colombiano Capítulo 6. Medidas de inclusión para una paz duradera Capítulo 7. Los desafíos de la asistencia humanitaria en el posacuerdo de paz en Colombia Bibliografí

Toward homochiral protocells in noncatalytic peptide systems

The activation-polymerization-epimerization-depolymerization (APED) model of Plasson et al. has recently been proposed as a mechanism for the evolution of homochirality on prebiotic Earth. The dynamics of the APED model in two-dimensional spatially-extended systems is investigated for various realistic reaction parameters. It is found that the APED system allows for the formation of isolated homochiral proto-domains surrounded by a racemate. A diffusive slowdown of the APED network such as induced through tidal motion or evaporating pools and lagoons leads to the stabilization of homochiral bounded structures as expected in the first self-assembled protocells.Comment: 10 pages, 5 figure

Cancer testis antigen and interleukin expression correlates with survival in small bowel neuroendocrine tumors

View full abstracthttps://openworks.mdanderson.org/leading-edge/1042/thumbnail.jp

Population-based prevalence of cervical infection with human papillomavirus genotypes 16 and 18 and other high risk types in Tlaxcala, Mexico

This study was supported by the National Institute of Public Health of Mexico, the Coordinación de Investigación en Salud del Instituto Mexicano del Seguro Social, the Secretaría de Salud Tlaxcala, the Instituto Nacional de las Mujeres, and the Consejo Nacional de Ciencia y Tecnología [FOSISS 2013 202468]. Additional support has been provided by Roche Diagnostics, BD Diagnostics, DICIPA and Arbor Vita Corporation. The study sponsors did not played a role in designing the study, collecting, analyzing or interpreting the data, writing the report, or submitting this paper for publication. UC Berkeley Center for Global Public Health, Schoeneman Grant, Joint Medical Program Thesis Grant, and Cancer Research UK (C569/A10404)

Plataforma técnica para la interoperabilidad de sistemas de información en la administración pública de la provincia de Santa Fe

El objetivo del presente proyecto es desarrollar una plataforma basada en una infraestructura de servicios web en el ámbito del Gobierno de la Provincia de Santa Fe, que permita sentar las bases de la Interoperabilidad en el Estado Provincial a través de la incorporación de herramientas que faciliten el intercambio de información digital y que sustenten las transacciones electrónicas, complementando las modalidades tradicionales de gestión. La plataforma desarrollada, la cual será identificada por el nombre “Administrador de Servicios Web” (ASW), permite el consumo de servicios web desde otros sistemas sin necesidad de gestionar la complejidad derivada de los protocolos específicos de estas tecnologías: la comunicación SOAP, la descripción WSDL o la búsqueda UDDI. Dicha plataforma proporciona una interfaz de acceso unificada, basada en protocolos estándares para que otras aplicaciones, plataformas o portales, puedan utilizar los servicios ofrecidos por la API de forma transparente. Además, se proporciona un interfaz de web que permite controlar qué servicios están registrados, con que métodos, y las características adicionales que soportan. El ASW se completa con un sistema de consulta a repositorios de servicios web, para ofrecer de forma intuitiva nuevos servicios, que podrán ser integrados en las aplicaciones corporativas o de usuario final.Sociedad Argentina de Informática e Investigación Operativ