Hemibrycon rafaelense sp. n. (Characiformes, Characidae), una nueva especie del alto Cauca, con claves de identificación para las especies colombianas

A new fish species of Hemibrycon is described from the San Rafael River, upper Cauca River, Colombia. H. rafaelense canbe distinguished from other species of the genus by the number of cusps on the teeth in the internal premaxilla row (3-5 vs. 5-7 except H. surinamensis), by the number of predorsal scales (10-12 vs. 12-17, except H. jelskii and H. orcesi), and by poscleithrum 1 (much closer to postcleithrum 2 vs. postcleithrum 1 and 2 clearly separated). Ecological data of the aquatic habitat of the new taxon are presented and keys to help identify known Colombian species are included. Key words: Hemibrycon, Tropical fish, South America.Se describe una nueva especie de Hemibrycon para el río San Rafael, alto Cauca, Colombia. H. rafaelense se diferencia de sus congéneres por el número de cúspides de la fila interna de dientes del premaxilar (3–5 vs. 5–7 excepto H. surinamensis), por el número de escamas predorsales (10–12 vs.12–17, excepto H. jelskii y H. orcesi), y por el postcleitrum 1 (mucho más próximo al postcleitrum 2 vs. postcleitrum 1 y 2 bien separados). Se incluyen datos ecológicos del hábitat propio del nuevo taxón y las claves para la identificación de las especies conocidas de Colombia. Palabras clave: Hemibrycon, Pez tropical, Sudamérica

Evolutionarily conserved enhancer-associated features within the <em>MYEOV </em>locus suggest a regulatory role for this non-coding DNA region in cancer

Copyright \ua9 2024 Davidson, Arcila-Galvis, Trevisan-Herraz, Mikulasova, Brackley, Russell and Rico.The myeloma overexpressed gene (MYEOV) has been proposed to be a proto-oncogene due to high RNA transcript levels found in multiple cancers, including myeloma, breast, lung, pancreas and esophageal cancer. The presence of an open reading frame (ORF) in humans and other primates suggests protein-coding potential. Yet, we still lack evidence of a functional MYEOV protein. It remains undetermined how MYEOV overexpression affects cancerous tissues. In this work, we show that MYEOV has likely originated and may still function as an enhancer, regulating CCND1 and LTO1. Firstly, MYEOV 3′ enhancer activity was confirmed in humans using publicly available ATAC-STARR-seq data, performed on B-cell-derived GM12878 cells. We detected enhancer histone marks H3K4me1 and H3K27ac overlapping MYEOV in multiple healthy human tissues, which include B cells, liver and lung tissue. The analysis of 3D genome datasets revealed chromatin interactions between a MYEOV-3′-putative enhancer and the proto-oncogene CCND1. BLAST searches and multi-sequence alignment results showed that DNA sequence from this human enhancer element is conserved from the amphibians/amniotes divergence, with a 273 bp conserved region also found in all mammals, and even in chickens, where it is consistently located near the corresponding CCND1 orthologues. Furthermore, we observed conservation of an active enhancer state in the MYEOV orthologues of four non-human primates, dogs, rats, and mice. When studying this homologous region in mice, where the ORF of MYEOV is absent, we not only observed an enhancer chromatin state but also found interactions between the mouse enhancer homolog and Ccnd1 using 3D-genome interaction data. This is similar to the interaction observed in humans and, interestingly, coincides with CTCF binding sites in both species. Taken together, this suggests that MYEOV is a primate-specific gene with a de novo ORF that originated at an evolutionarily older enhancer region. This deeply conserved putative enhancer element could regulate CCND1 in both humans and mice, opening the possibility of studying MYEOV regulatory functions in cancer using non-primate animal models

Selection of unsaturated polyester resins for closed resin transfer moulding processes

En este artículo se analizan tres tipos de resinas poliéster in-saturado comerciales de amplio uso en el mercado nacional y se evalúa su conveniencia de uso en procesos de transferencia de resina en molde cerrado (RTM), de acuerdo con criterios de visco-sidad y reactividad. Se compara la viscosidad de las resinas entre 15 y 50°C, así como la reactividad mediante curvas de curado a temperatura ambiente, con porcentajes de catalizador del 1, 1.5 y 2%. De acuerdo con los resultados se determinó que algunas de las resinas son susceptibles de uso en procesos RTM, por su apropiada viscosidad, estabilidad en la reactividad y su velocidad de curado. Estas características son de gran importancia al momento de seleccionar las resinas poliéster insaturado, de acuerdo con las condiciones del proceso en molde cerrado.In this paper three commercial unsaturated polyester resins of wide use in Colombia are analyzed and it is evaluated the convenience of their use in resin transfer molding processes according to viscosity and reactivity criteria. The resin viscosities are compared between 15 and 50°C, in the same way as the reactivity by mean of the curing curves at room temperature, using catalyst at 1, 1.5 and 2%. In agreement with the results, it was determined that some resins are suitable for RTM process, because of their appropriate viscosity, consistent reactivity and curing velocity. These features are of great importance in the unsaturated polyester resin selection, according to conditions of closed mold processes

Bayesian molecular clock dating of species divergences in the genomics era

It has been five decades since the proposal of the molecular clock hypothesis, which states that the rate of evolution at the molecular level is constant through time and among species. This hypothesis has become a powerful tool in evolutionary biology, making it possible to use molecular sequences to estimate the geological ages of species divergence events. With recent advances in Bayesian clock dating methodology and the explosive accumulation of genetic sequence data, molecular clock dating has found widespread applications, from tracking virus pandemics, to studying the macroevolutionary process of speciation and extinction, to estimating a timescale for Life on Earth

Voids by mechanical entrapment in liquid molding processes: mechanism of formation, influence in the mechanical response and reduction

Los vacíos por atrapamiento mecánico se constituyen en unos de los tipos de defectos más comunes en el procesado de Composites por moldeo líquido. Debido a la gran influencia que tienen estos vacíos en el desempeño de la pieza final, una cantidad considerable de investigaciones se han centrado en el estudio de los mecanismos de formación de los mismos, de la influencia que éstos tienen en las propiedades mecánicas del compuesto y de las estrategias para su reducción durante el procesado. El presente trabajo pretende realizar una revisión de algunas investigaciones relevantes que se han hecho en el tema de vacíos formados por atrapamiento mecánico de aire en el procesado de compuestos por LCM (Moldeo Líquido de Composites, por sus siglas en inglés), con el objetivo de generar un material de referencia dirigido a investigadores interesados en esta importante temática relacionada con las áreas del procesado y comportamiento mecánico de materiales compuestos. Serán abordados temas como: el mecanismo de formación por desbalance entre macroflujo y microflujo, y su relación con el número capilar modificado y el efecto de sumidero; los fenómenos de compresibilidad, disolución y movimiento de burbujas en preformas de doble escala; la influencia de los vacíos en las propiedades mecánicas del composite y en los mecanismos de daño; y las estrategias más comunes que pueden ser implementadas a nivel industrial para la reducción de este tipo de defectología.The voids by mechanical entrapment become as one of the most common type of defects in the liquid molding processing of composites. Because of the strong influence of those kind of voids in the general performance of the manufactured part, an important amount of researches have focused on the study of the mechanisms of formation of those voids, of the influence of the those ones on the mechanical properties of the composite and of the strategies for their reduction during the process. The present paper aims to do a review of some relevant investigations that have been done in the topic of voids caused by mechanical entrapment of air in the processing of composites by LCM (Liquid composites molding) with the purpose of generate a reference material addressed to researchers that are interested in this important subject matter related to the areas of processing and mechanical behavior of composites materials. They will be addressed some topics like: the mechanism of void formation by imbalance among macroflow and microflow and its relationship with the modified capillary number and the sink effect; the phenomena of compressibility, dissolution and mobilization of bubbles in dual-scale preforms; the influence of voids on the mechanical properties of the composites and on the damage mechanisms; and the most common strategies that can be implemented in the industry for the reduction of this sort of defects

Konvencionalna i funkcionalna procjena sjemena mužjaka mliječnih koza

Evaluating the reproductive indicators in sheep breeding in Colombia, particularly males, is essential to achieve optimal production parameters. This study aimed to evaluate the semen quality of male goats through both conventional and functional seminal analysis. Semen samples from eight goats were collected and conventional (volume, appearance, colour, motility, vigour, and morphology) and functional (plasma membrane integrity, mitochondrial membrane potential, DNA integrity, lipid peroxidation, and reactive oxygen species production) seminal parameters were evaluated. The results showed an average scrotal circumference of 25.69 cm, seminal volume of 0.51 mL, and concentration of 1936 x 106 sperm/mL. The average individual motility was 63.37%, vigour was four, and the percentage of abnormalities was 7.75%. Individual motility was correlated with the mitochondrial membrane potential (r=0.840, P=0.009) and reactive oxygen species production (r=-0.91, P=0.001). The average of cells with high mitochondrial membrane potential was 52.94%, while 39.29% were necrotic cells, the DNA fragmentation index average was 12.5%, reactive oxygen species production was 38.68%, lipoperoxidation analysis was 7.33% on average, and the integrity of the membrane was 54.77%. The results establish the parameters for the semen from Antioquia goats and confirm that goat semen is of good quality and could be used during artificial insemination programs.Procjena reproduktivnih indikatora u stadima koza u Kolumbiji fokusirana je na mužjake i od osnovne je važnosti za postizanje optimalnih produktivnih parametara. Cilj je ove studije bio ocijeniti kvalitetu sjemena jaraca kroz konvencionalnu i funkcionalnu analizu sjemena. Prikupljeni su uzorci sjemena osam jaraca te su procijenjeni konvencionalni (volumen, izgled, boja, pokretljivost, vitalnost i morfologija) i funkcionalni (integritet stanične membrane, potencijal mitohondrijske membrane, integritet DNK, peroksidacija lipida i proizvodnja reaktivnih spojeva kisika) parametri. Rezultati su pokazali prosječni opseg skrotuma od 25,69 cm, 0,51 mL za volumen sjemena, 1936 x 106 spermija/mL za koncentraciju. Prosječna pojedinačna pokretljivost bila je 63,37 %, vitalnost je bila četiri, a postotak abnormalnosti bio je 7,75 %. Pojedinačna pokretljivost povezana je s potencijalom mitohondrijske membrane (r=0,840, P=0,009) i proizvodnjom reaktivnih spojeva kisika (r=-0,91, P=0,001). Prosjek stanica s visokim potencijalom mitohondrijske membrane bio je 52,94 %, dok je bilo 39,29 % nekrotičnih stanica, prosječni indeks fragmentacije DNK bio je 12,5 %, proizvodnja reaktivnih spojeva kisika bila je 38,68 %, analiza lipoperoksidacije bila je u prosjeku 7,33 %, a integritet membrane 54,77 %. Rezultati utvrđuju parametre za sjeme antioquia koza i potvrđuje da sjeme jaraca predstavlja dobru kvalitetu i moglo bi se koristiti u programima umjetne oplodnje

Genetic mapping reveals Nfkbid as a central regulator of humoral immunity to Toxoplasma gondii

Protective immunity to parasitic infections has been difficult to elicit by vaccines. Among parasites that evade vaccine-induced immunity is Toxoplasma gondii, which causes lethal secondary infections in chronically infected mice. Here we report that unlike susceptible C57BL/6J mice, A/J mice were highly resistant to secondary infection. To identify correlates of immunity, we utilized forward genetics to identify Nfkbid, a nuclear regulator of NF-κB that is required for B cell activation and B-1 cell development. Nfkbid-null mice ("bumble") did not generate parasite-specific IgM and lacked robust parasite-specific IgG, which correlated with defects in B-2 cell maturation and class-switch recombination. Though high-affinity antibodies were B-2 derived, transfer of B-1 cells partially rescued the immunity defects observed in bumble mice and were required for 100% vaccine efficacy in bone marrow chimeric mice. Immunity in resistant mice correlated with robust isotype class-switching in both B cell lineages, which can be fine-tuned by Nfkbid gene expression. We propose a model whereby humoral immunity to T. gondii is regulated by Nfkbid and requires B-1 and B-2 cells for full protection

Pre-professional journalistic cultures of Cuba, Ecuador and Venezuela: Perceptions of students about ethics and journalism practices

This paper analyses the pre-professional journalistic culture of Ecuador, Cuba and Venezuela based on the degree of permissiveness held by Journalism students in regard to controversial ethical practices and their views of the media and the journalistic profession. We surveyed a probabilistic sample of 1,273 students from 21 universities enrolled on their first course (Ecuador=500, Venezuela=390, Cuba=383) in 2016. The results show that future journalists are reluctant to accept questionable journalistic practices, and hold a pessimistic view as to the quality and confidence of the media and the profession. We found that the degree of permissiveness is related to the perceived risk-reward analysis in terms of the quality of journalism in Cuba and Ecuador, and that the student perceptions of ethics differ in Venezuela and Ecuador. We conclude that, despite their political similarities in terms of having left-wing Governments, perceptions in the three countries diverge

Brucelosis bovina en Colombia: ¿qué valor tienen los estudios de seroprevalencia?

La brucelosis bovina sigue siendo considerado internacionalmente un problema de salud animal y zoonótico de gran importancia. En países como Colombia, sin duda se requiere realizar más estudios para entender su comportamiento epidemiológico, así como su relevancia para la salud animal y humana. En tal sentido, queremos aprovechar la oportunidad para discutir sobre el valor de los estudios de seroprevalencia de bovinos. Por ejemplo, el artículo: ¨seroprevalencia de brucelosis bovina en dos localidades del Caribe Colombiano¨ [1], puede ser de gran ayuda para poder entender y comprender claramente como es la seroprevalencia de brucelosis bovina en el territorio colombiano. Como decíamos, ya que esto no ha sido muy estudiado en profundidad por lo cual es evidente que hay grandes vacíos en el momento de búsqueda de información sobre tan importante tema, trayendo como consecuencias la afectación de la economía ganadera, bienestar animal y la salud pública, ya que esta es una enfermedad de tipo zoonótica que afectan a diferentes especies de animales como también a las personas que entran en contacto directo con esta bacteria, estando presente no solo en Colombia sino también a nivel mundial en muchísimos países

Transferencia de tecnología para las líneas 2 y 6 de 1995, como nuevas variedades mejoradas de trigo para modernización del cultivos en las zonas productivas A y B del departamento de Nariño :informe final del proyecto

Este proyecto desarrollado entre octubre de 1996 y diciembre de 1998, se realizó en las zonas productivas A y B ubicadas entre 2401 - 3000 m.s.n.m. de los municipios trigueros de : Cuaspud (Carlosama), lpiales, Pupiales, Túquerres, Sapuyes, Ospina, lles, Pasto, Yacuanquer, Tangua, Guaitarilla, Gualmatán, Cumbal e lmués, con el fin de ajustar y transferir tecnología para las líneas promisorias de trigo 2 y 6 de 1995. En 1997, luego de la evaluación y promoción de las líneas promisorias, se entregó la línea 2 de 1995 como nueva variedad mejorada para cultivarse en la zona productiva A de modernización, denominándose OBONUCO SUREÑO 97. Para 1998, se evaluó y entregó la línea 6 de 1995 (la cual reemplazó a la línea 16 de 1995) como otra nueva variedad para la zona productiva B, denominándose OBONUCO OBANDO 98. El fin de estas dos nuevas variedades es atracar a los productores variedades con resistencia a las enfermedades más limitantes como la roya amarilla, con altos rendimientos y con la calidad del grano exigida por los industriales; todo lo anterior para mejorar la competitividad del cultivo.Trigo-Triticum aestiv