Horizontal gene transfer and diverse functional constrains within a common replication-partitioning system in Alphaproteobacteria: the repABC operon

<p>Abstract</p> <p>Background</p> <p>The <it>repABC </it>plasmid family, which is extensively present within <it>Alphaproteobacteria</it>, and some secondary chromosomes of the <it>Rhizobiales </it>have the particular feature that all the elements involved in replication and partitioning reside within one transcriptional unit, the <it>repABC </it>operon. Given the functional interactions among the elements of the <it>repABC </it>operon, and the fact that they all reside in the same operon, a common evolutionary history would be expected if the entire operon had been horizontally transferred. Here, we tested whether there is a common evolutionary history within the <it>repABC </it>operon. We further examined different incompatibility groups in terms of their differentiation and degree of adaptation to their host.</p> <p>Results</p> <p>We did not find a single evolutionary history within the <it>repABC </it>operon. Each protein had a particular phylogeny, horizontal gene transfer events of the individual genes within the operon were detected, and different functional constraints were found within and between the Rep proteins. When different <it>repABC </it>operons coexisted in the same genome, they were well differentiated from one another. Finally, we found different levels of adaptation to the host genome within and between <it>repABC </it>operons coexisting in the same species.</p> <p>Conclusion</p> <p>Horizontal gene transfer with conservation of the <it>repABC </it>operon structure provides a highly dynamic operon in which each member of this operon has its own evolutionary dynamics. In addition, it seems that different incompatibility groups present in the same species have different degrees of adaptation to their host genomes, in proportion to the amount of time the incompatibility group has coexisted with the host genome.</p

Modelo difuso para la inspección visual de superficies metálicas ferrosas corroídas

Se presenta el desarrollo de un modelo difuso (MD), diseñado para inspeccionar visualmente superficies metálicas ferrosas expuestas a procesos corrosivos tales como picadura o corrosión atmosférica. Los parámetros considerados como datos de entrada, son variables visuales macroscópicas que se presentan en algunos de los fenómenos corrosivos. Estas variables fueron establecidas con base en normas estándar emitidas por la ASTM, artículos de investigación, ASM Handbooks volume 13 y 13 A, entre otros. Se realizó una discretización de sólo cinco variables como parámetros de entrada para reconocer hasta cinco procesos corrosivos. Para validar el funcionamiento del MD, se llevaron a cabo pruebas con base a fotografías de artículos de investigación en el análisis de falla de ingeniería obteniendo resultados favorables

Honduras 2013 : proceso electoral, financiamiento y transparencia. Informe de monitoreo

El proceso electoral que concluyó con la celebración de las elecciones generales el domingo 24 de noviembre del an&#771;o 2013, fue un proceso especial y de gran significado en la historia de la transición política hacia la democracia en la sociedad honduren&#771;a. A lo largo de esta transición, a veces tan errática y difícil como incierta y prolongada, los honduren&#771;os hemos ido a las urnas en una decena de veces para escoger a nuestros gobernantes. Pero nunca antes el torneo electoral había sido tan abierto y plural, así como tan ren&#771;ido y polarizado ideológicamente, como lo ha sido en esta ocasión. Marcadas por la impronta del reciente golpe de Estado perpetrado el 28 de junio del an&#771;o 2009, las elecciones de 2013 se llevaron a cabo en medio de un clima de mucha expectación ciudadana y grandes posibilidades de llevar a cabo cambios políticos importantes en la vida de la nación. Nunca antes el status quo había sido tan cuestionado y puesto en duda como en el proceso electoral del an&#771;o 2013

Combining Freestanding Ferroelectric Perovskite Oxides with Two-Dimensional Semiconductors for High Performance Transistors

[EN] We demonstrate the fabrication of field-effect transistors based on single-layer MoS2 and a thin layer of BaTiO3 (BTO) dielectric, isolated from its parent epitaxial template substrate. Thin BTO provides an ultrahigh-κ gate dielectric effectively screening Coulomb scattering centers. These devices show mobilities substantially larger than those obtained with standard SiO2 dielectrics and comparable with values obtained with hexagonal boron nitride, a dielectric employed for fabrication of high-performance two-dimensional (2D) based devices. Moreover, the ferroelectric character of BTO induces a robust hysteresis of the current vs gate voltage characteristics, attributed to it polarization switching. This hysteresis is strongly suppressed when the device is warmed up above the tetragonal-to-cubic transition temperature of BTO that leads to a ferroelectric-to-paraelectric transition. This hysteretic behavior is attractive for applications in memory storage devices. Our results open the door to the integration of a large family of complex oxides exhibiting strongly correlated physics in 2D-based devices.European Research Council (ERC) through the project 2DTOPSENSE (GA 755655) European Union’sHorizon 2020 research and innovation program (Graphene Core2-Graphenebased disruptive technologies and Grant Agreement 881603 Graphene Core3-Graphene-based disruptive technologies) EU FLAG-ERA through the project To2Dox (JTC-2019-009) Comunidad de Madrid through the project CAIRO-CM project (Y2020/NMT-6661) Spanish Ministry of Science and Innovation through the projects PID2020-118078RBI00 RTI2018-099054-J-I00 and IJC2018-038164-I, PRE2018-084818 Key Research and Development Program of Shaanxi (Program No.2021KW-02).Peer reviewe

Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models

Subcortical volumes across the lifespan: Data from 18,605 healthy individuals aged 3–90 years

Age has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry. In response, we capitalized on the resources of the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to examine age‐related trajectories inferred from cross‐sectional measures of the ventricles, the basal ganglia (caudate, putamen, pallidum, and nucleus accumbens), the thalamus, hippocampus and amygdala using magnetic resonance imaging data obtained from 18,605 individuals aged 3–90 years. All subcortical structure volumes were at their maximum value early in life. The volume of the basal ganglia showed a monotonic negative association with age thereafter; there was no significant association between age and the volumes of the thalamus, amygdala and the hippocampus (with some degree of decline in thalamus) until the sixth decade of life after which they also showed a steep negative association with age. The lateral ventricles showed continuous enlargement throughout the lifespan. Age was positively associated with inter‐individual variability in the hippocampus and amygdala and the lateral ventricles. These results were robust to potential confounders and could be used to examine the functional significance of deviations from typical age‐related morphometric patterns

Cortical thickness across the lifespan: Data from 17,075 healthy individuals aged 3-90 years

Delineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large‐scale studies. In response, we used cross‐sectional data from 17,075 individuals aged 3–90 years from the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to infer age‐related changes in cortical thickness. We used fractional polynomial (FP) regression to quantify the association between age and cortical thickness, and we computed normalized growth centiles using the parametric Lambda, Mu, and Sigma method. Interindividual variability was estimated using meta‐analysis and one‐way analysis of variance. For most regions, their highest cortical thickness value was observed in childhood. Age and cortical thickness showed a negative association; the slope was steeper up to the third decade of life and more gradual thereafter; notable exceptions to this general pattern were entorhinal, temporopolar, and anterior cingulate cortices. Interindividual variability was largest in temporal and frontal regions across the lifespan. Age and its FP combinations explained up to 59% variance in cortical thickness. These results may form the basis of further investigation on normative deviation in cortical thickness and its significance for behavioral and cognitive outcomes

Detección de metales pesados y dicloro difenil tricloro etano (DDT) en músculos y órganos de bovinos en Yucatán

The purpose of this research was to determine copper (Cu), lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), dichlorodiphenyl-trichloroethane (DDT), and DDT metabolites, in the muscles and organs of cattle slaughtered in Mérida, Yucatan, Mexico, during 13 months. Pectoral muscle, kidney and liver were sampled in the Faculty of Veterinary Medicine and Animal Husbandry Processing Plant (RVet) (n=255), and in Mérida City Municipal Slaughter House (RMun) (n=225), from April 2001 to April 2002. Samples were analyzed using an atomic absorption spectrophotometer provided with hollow cathode lamps and an air-acetylene burner to determine Cu, Pb, and Cd, or by means of the use of cold vapor for Hg, or finally using a hydride generator for As. DDT and DDT metabolites were determined using a gas chromatographer with an electron capture detector. Results were analyzed calculating the general means and dispersion parameters as well as using the least square method to detect the effects of sample type, abattoir and season of the year, as well as all interactions. Cu content in 79 % of all the samples was higher than the limit recommended by Mexican Official Norms (MON's). The quantity was highest in liver samples. Cu levels were higher (PEl objetivo fue determinar cobre (Cu), plomo (Pb), cadmio (Cd), mercurio (Hg), arsénico (As), dicloro difenil tricloro etano (DDT) y sus metabolitos, en músculos y órganos de bovinos sacrificados en Mérida, Yucatán, México, durante trece meses. Se muestrearon músculo pectoral, riñón e hígado en el rastro de la Facultad de Medicina Veterinaria y Zootecnia (RVet) (n=255) y en el rastro Municipal de Mérida (RMun) (n=225), de abril de 2001 a abril de 2002. Se analizaron mediante espectrofotometría de absorción atómica, empleando lámparas de cátodo hueco y un quemador de aire-acetileno para determinar Cu, Pb y Cd, vapor frío (Hg) o mediante generación de hidruros (As). El DDT y sus metabolitos fueron determinados empleando un cromatógrafo de gases con un detector de captura de electrones. Los resultados se analizaron calculando su media general y parámetros de dispersión, así como por el método de mínimos cuadrados para detectar el efecto del tipo de muestra, del rastro, de la época del año, así como las interacciones. El contenido de Cu en el 79 % de las muestras fue mayor al límite permitido por la Norma Oficial Mexicana (NOM), destacándose el elevado contenido hepático. El contenido de Cu fue mayor en el RVet y durante diciembre a abril (

Cuantificación del contenido de cobre y otros minerales en pollinazas producidas en el estado de Yucatán

Analyses were made to quantify the copper (Cu), sulfur (S), iron (Fe), zinc (Zn) and molybdenum (Mo) contents of poultry manure marketed by three of the most important poultry companies in the State of Yucatan, Mexico. Manure samples were taken weekly over a one-year period, from June 2000 to May 2001. Atomic absorption spectrophotometry analysis was done of dry matter, ash, Cu, S, Fe, Zn and Mo. Results were grouped according to company of origin (Company 1, 2 and 3) and annual season (rainy, June -,, October, windy, November -,, January, dry, February -,, May. Data was analyzed by the least-squares method using a model including the general mean, the effect of the season, the effect of the company of origin x season interaction and the random error [NiD (0, s2)]. Cu content in poultry manure was 82 ppm and was affected by the company of origin (PEl estudio se llevó a cabo con la finalidad de cuantificar el contenido de cobre (Cu), azufre (S), hierro (Fe), zinc (Zn) y molibdeno (Mo) en la pollinaza comercializada por tres de las más importantes empresas de Yucatán. La recolección de muestras se realizó semanalmente durante 12 meses comprendidos entre junio del 2000 y mayo del 2001. A las muestras se les determinó materia seca, materia mineral, así­ como Cu, S, Fe, Zn y Mo mediante espectrofotometrí­a de absorción atómica. Los resultados se agruparon dependiendo de su procedencia (Empresas 1, 2 y 3) y por época del año: lluvias (junio -,, octubre), nortes (noviembre -,, enero) y seca (febrero -,, mayo), y se analizaron mediante el método de cuadrados mí­nimos empleando un modelo lineal de efectos fijos. El promedio general del contenido de Cu en la pollinaza fue de 82 ppm, y estuvo afectado por la procedencia (