Evaluación de la transferencia metálica y estabilidad del proceso GMAW

The metal transfer, as a particularity of the process with consumable electrodes, has a direct influence on different aspects of the welding process. Hence, the operation performance is affected by the quantity of spatter and mostly, in the stability where the electrical phenomena happen. This work established a methodology to compare techniques for the definition of stability in the forms of metal transfer presented in the GMAW process. For that, welding tests were carried out in the flat position, establishing parameters, and modifying the voltage between a range of 14 to 32 V. In addition, it was analyzed the behavior of the process using histograms, stability indicators, and weld bead geometry characterization. As a result, high process instability and splashing of low voltages were obtained, improving these conditions for higher voltages. In conclusion, the best conditions for the welding process are established at the point with the highest frequency of short circuits, exhibiting a minimum of spatter and the best welding bead.La transferencia metálica, como particularidad del proceso con electrodos consumibles, ejerce influencia directa sobre variados aspectos del proceso de soldadura; de este modo, el desempeño operacional de la técnica se ve afectado por un mayor o menor nivel de salpicaduras y, en general, por la estabilidad con que los fenómenos eléctricos ocurren. En el presente artículo fue establecida una metodología que permitió comparar técnicas para la definición de la estabilidad, en los tipos de transferencia metálica presentados en el proceso GMAW. Para esto, se realizaron ensayos de soldadura en la posición plana, estableciendo parámetros y variando el voltaje entre un rango de 14 a 32 V. Además, fue analizado el comportamiento del proceso, mediante el uso de histogramas, índices de estabilidad y la caracterización de la geometría del cordón. Como resultado, se obtuvo alta inestabilidad del proceso y salpicaduras en bajas tensiones, mejorando estas condiciones para las tensiones más altas. En conclusión, en el punto de mayor frecuencia de cortos circuitos se establecen las mejores condiciones para el proceso de soldadura, exhibiendo un mínimo de salpicaduras y el cordón de soldadura con mejor formato.&nbsp

A neurodegenerative disease landscape of rare mutations in Colombia due to founder effects

Background The Colombian population, as well as those in other Latin American regions, arose from a recent tri-continental admixture among Native Americans, Spanish invaders, and enslaved Africans, all of whom passed through a population bottleneck due to widespread infectious diseases that left small isolated local settlements. As a result, the current population reflects multiple founder effects derived from diverse ancestries. Methods We characterized the role of admixture and founder effects on the origination of the mutational landscape that led to neurodegenerative disorders under these historical circumstances. Genomes from 900 Colombian individuals with Alzheimer’s disease (AD) [n = 376], frontotemporal lobar degeneration-motor neuron disease continuum (FTLD-MND) [n = 197], early-onset dementia not otherwise specified (EOD) [n = 73], and healthy participants [n = 254] were analyzed. We examined their global and local ancestry proportions and screened this cohort for deleterious variants in disease-causing and risk-conferring genes. Results We identified 21 pathogenic variants in AD-FTLD related genes, and PSEN1 harbored the majority (11 pathogenic variants). Variants were identified from all three continental ancestries. TREM2 heterozygous and homozygous variants were the most common among AD risk genes (102 carriers), a point of interest because the disease risk conferred by these variants differed according to ancestry. Several gene variants that have a known association with MND in European populations had FTLD phenotypes on a Native American haplotype. Consistent with founder effects, identity by descent among carriers of the same variant was frequent. Conclusions Colombian demography with multiple mini-bottlenecks probably enhanced the detection of founder events and left a proportionally higher frequency of rare variants derived from the ancestral populations. These findings demonstrate the role of genomically defined ancestry in phenotypic disease expression, a phenotypic range of different rare mutations in the same gene, and further emphasize the importance of inclusiveness in genetic studies.Q2Q2Antecedentes La población colombiana, así como la de otras regiones latinoamericanas, surgió de una mezcla tricontinental reciente entre los nativos americanos, los invasores españoles y los africanos esclavizados, todos los cuales pasaron por un cuello de botella poblacional debido a enfermedades infecciosas generalizadas que dejaron a pequeños aislados. asentamientos locales. Como resultado, la población actual refleja múltiples efectos fundadores derivados de diversas ascendencias. Métodos Caracterizamos el papel de la mezcla y los efectos fundadores en el origen del paisaje mutacional que condujo a trastornos neurodegenerativos en estas circunstancias históricas. Genomas de 900 individuos colombianos con enfermedad de Alzheimer (EA) [n = 376], continuo degeneración lobar frontotemporal-enfermedad de la motoneurona (FTLD-MND) [n = 197], demencia de inicio temprano no especificada (EOD) [n = 73 ], y participantes sanos [n = 254] fueron analizados. Examinamos sus proporciones de ascendencia global y local y examinamos esta cohorte en busca de variantes nocivas en los genes que causan enfermedades y confieren riesgos. Resultados Identificamos 21 variantes patogénicas en genes relacionados con AD-FTLD, y PSEN1 albergaba la mayoría (11 variantes patogénicas). Se identificaron variantes de las tres ascendencias continentales. Las variantes heterocigotas y homocigotas de TREM2 fueron las más comunes entre los genes de riesgo de EA (102 portadores), un punto de interés porque el riesgo de enfermedad conferido por estas variantes difería según la ascendencia. Varias variantes genéticas que tienen una asociación conocida con MND en poblaciones europeas tenían fenotipos FTLD en un haplotipo nativo americano. De acuerdo con los efectos del fundador, la identidad por descendencia entre portadores de la misma variante fue frecuente. Conclusiones La demografía colombiana con múltiples mini-cuellos de botella probablemente mejoró la detección de eventos fundadores y dejó una frecuencia proporcionalmente más alta de variantes raras derivadas de las poblaciones ancestrales. Estos hallazgos demuestran el papel de la ascendencia definida genómicamente en la expresión fenotípica de la enfermedad, un rango fenotípico de diferentes mutaciones raras en el mismo gen, y enfatizan aún más la importancia de la inclusión en los estudios genéticos.https://orcid.org/0000-0001-6529-7077https://scholar.google.com/citations?hl=es&user=kaGongoAAAAJ&view_op=list_works&sortby=pubdatehttps://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000055000&lang=esRevista Internacional - Indexad

A neurodegenerative disease landscape of rare mutations in Colombia due to founder effects.

Background: The Colombian population, as well as those in other Latin American regions, arose from a recent tri-continental admixture among Native Americans, Spanish invaders, and enslaved Africans, all of whom passed through a population bottleneck due to widespread infectious diseases that left small isolated local settlements. As a result, the current population reflects multiple founder effects derived from diverse ancestries. Methods: We characterized the role of admixture and founder effects on the origination of the mutational landscape that led to neurodegenerative disorders under these historical circumstances. Genomes from 900 Colombian individuals with Alzheimer's disease (AD) [n = 376], frontotemporal lobar degeneration-motor neuron disease continuum (FTLD-MND) [n = 197], early-onset dementia not otherwise specified (EOD) [n = 73], and healthy participants [n = 254] were analyzed. We examined their global and local ancestry proportions and screened this cohort for deleterious variants in disease-causing and risk-conferring genes. Results: We identified 21 pathogenic variants in AD-FTLD related genes, and PSEN1 harbored the majority (11 pathogenic variants). Variants were identified from all three continental ancestries. TREM2 heterozygous and homozygous variants were the most common among AD risk genes (102 carriers), a point of interest because the disease risk conferred by these variants differed according to ancestry. Several gene variants that have a known association with MND in European populations had FTLD phenotypes on a Native American haplotype. Consistent with founder effects, identity by descent among carriers of the same variant was frequent. Conclusions: Colombian demography with multiple mini-bottlenecks probably enhanced the detection of founder events and left a proportionally higher frequency of rare variants derived from the ancestral populations. These findings demonstrate the role of genomically defined ancestry in phenotypic disease expression, a phenotypic range of different rare mutations in the same gene, and further emphasize the importance of inclusiveness in genetic studies

Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Publisher Copyright: © 2021, The Author(s).Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.Peer reviewe

Search for top squark pair production in pp collisions at root s=13 TeV using single lepton events

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Search for narrow resonances in dilepton mass spectra in proton-proton collisions at root s=13 TeV and combination with 8 TeV data

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Search for heavy gauge W ' bosons in events with an energetic lepton and large missing transverse momentum at root s=13TeV

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Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change

Search for massive resonances decaying in to WW,WZ or ZZ bosons in proton-proton collisions at root s=13 TeV

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Search for anomalous Wtb couplings and flavour-changing neutral currents in t-channel single top quark production in pp collisions at root s=7 and 8 TeV

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