FixL-like sensor FlbS of Brucella abortus binds haem and is necessary for survival within eukaryotic cells

AbstractReplication of Brucella inside eukaryotic cells is essential for pathogenesis, and successful infection requires rapid adaptation to the intracellular milieu. Close relatives of Brucella use the two-component system FixLJ to survive inside the host. We aimed to identify a homologous sensor in Brucella abortus. A predicted protein with transmembrane and conserved histidine kinase domains was identified as the Fix-like Brucella sensor, FlbS. Although it lacks the PAS domain, recombinant FlbS binds haem in vitro. An internal in-frame deletion in flbS severely decreased B. abortus survival inside professional and non-professional phagocytes. This phenotype was reverted by genetic complementation. These results indicate the critical role of this haemoprotein in the intracellular lifestyle of Brucella

Fuentes para la historia de la tierra pública del Territorio del Chaco

El Instituto de Colonización de la provincia del Chaco resguarda numerosos expedientes que nos posibilitan conocer la historia de la tierra en el Chaco desde la formación del Territorio hasta la actualidad. Entre esa documentación destacamos las mensuras y las inspecciones. Ambas tienen un gran valor para la reconstrucción histórica porque constituyen un detallado registro sobre el poblamiento de las tierras fiscales y la creación de colonias y pueblos. El presente trabajo tiene como objeto la descripción del archivo del instituto de Colonización. Para ello, primeramente, especificaremos el funcionamiento de la repartición destacando las secciones que posee, señalando asimismo el lugar donde se encuentran los expedientes y las contribuciones al conocimiento histórico que este tipo de fuentes puede brindar al estudio de la tierra pública

Fuentes para la historia de la tierra pública del Territorio del Chaco

El Instituto de Colonización de la provincia del Chaco resguarda numerosos expedientes que nos posibilitan conocer la historia de la tierra en el Chaco desde la formación del Territorio hasta la actualidad. Entre esa documentación destacamos las mensuras y las inspecciones. Ambas tienen un gran valor para la reconstrucción histórica porque constituyen un detallado registro sobre el poblamiento de las tierras fiscales y la creación de colonias y pueblos. El presente trabajo tiene como objeto la descripción del archivo del instituto de Colonización. Para ello, primeramente, especificaremos el funcionamiento de la repartición destacando las secciones que posee, señalando asimismo el lugar donde se encuentran los expedientes y las contribuciones al conocimiento histórico que este tipo de fuentes puede brindar al estudio de la tierra pública

A new species of Hyphessobrycon (Characiformes, Characidae) from the Esteros del Iberá wetlands, Argentina

Hyphessobrycon auca sp. n. is described from the Esteros del Iberá wetlands. Hyphessobrycon auca differs from the remaining species of the genus by the presence of one maxillary tooth with 5 cusps; dentary low with teeth decreasing in size anteroposteriorly; males with hooks in all fins; mature females with hooks on pelvic-fin rays; one humeral spot vertically elongated, bounded by a light area; a second lateral spot may be faint or well developed; a wide lateral band ending in a conspicuous caudal spot.Facultad de Ciencias Naturales y Muse

A new species of Hyphessobrycon (Characiformes, Characidae) from the Esteros del Iberá wetlands, Argentina

Hyphessobrycon auca sp. n. is described from the Esteros del Iberá wetlands. Hyphessobrycon auca differs from the remaining species of the genus by the presence of one maxillary tooth with 5 cusps; dentary low with teeth decreasing in size anteroposteriorly; males with hooks in all fins; mature females with hooks on pelvic-fin rays; one humeral spot vertically elongated, bounded by a light area; a second lateral spot may be faint or well developed; a wide lateral band ending in a conspicuous caudal spot.Facultad de Ciencias Naturales y Muse

Diet of Hyphessobrycon auca (Pisces, characidae) in Iberá Wetland (Northeastern, Argentina)

Hyphessobrycon auca Almirón, Casciotta, Bechara & Ruiz Díaz, 2004, inhabit small lakes located at the northwest of Iberá wetland in Argentina. This research describes sorne aspects of its feeding. Samples were collected from its type locality from 2007 to 2009. Analysis of 70 digestive tracts of individuals ranging from 24 to 56 mm standard length (SL) showed that higher plants, algae, and quironomids larvae dominated the diet in terms of relative volume and occurrence frequency. Therefore, this species was characterized as omnivorous, but there was a growing trend towards herbivory when size class incremed. Smaller size class (< 35 mm SL) fed on higher proportion of animal preys such as quironomids larvae and protozoans, in contrast to larger ones who consumed almost exclusively plants and algae

Learning analytics of mobile learning (m-learning) in secondary education

La integración de la tecnología móvil en los procesos de enseñanza y aprendizaje, conocido como aprendizaje electrónico móvil (m-learning) encuentra resistencia de parte de los docentes de la educación secundaria. Esta situación lleva a que las investigaciones en el tema resulten escasas, generando en la comunidad de docentes actitudes ingenuas y poco informadas acerca del m-learning. Específicamente, el m-learning es una de las áreas menos investigadas, por su propia naturaleza móvil, portable y ubicua, que genera comportamientos e interacciones tecno-sociales complejos y no deterministas. Es por ello que esta investigación utiliza el learning analytic para evaluar los datos que se obtienen de las interacciones tecnológicas y pedagógicas del m-learning. El estudio de caso se realizó con dos cohortes: 2018 (N = 16) y 2019 (N = 12). Para el análisis se utilizaron los datos obtenidos de logs de interacciones que se descarga de la aplicación disponible en el smartphone. Como resultado, se encuentra que el m-learning, es un sistema de aprendizaje binario b-learning que promueven un perfil de usuarios con la capacidad de gestionar los tiempos de aprendizaje ubicuo y potencia la gestión de los metaespacios de aprendizaje electrónico distribuido.The integration of mobile technology into teaching and learning processes, known as mobile e-learning (m-learning), meets resistance from secondary school teachers. This situation leads to scarce research on the subject, generating naive and poorly informed attitudes about m-learning in the community of teachers. Specifically, m-learning is one of the least investigated areas, due to its own mobile, portable and ubiquitous nature, which generates complex and non-deterministic techno-social behaviors and interactions. That is why this research uses learning analytic to evaluate the data obtained from the technological and pedagogical interactions of m-learning. The case study was carried out with two cohorts: 2018 (N = 16) and 2019 (N = 12). For the analysis, the data obtained from interaction logs that is downloaded from the application available on the smartphone were used. As a result, m-learning is found to be a binary-learning binary learning system that promotes a user profile with the ability to manage ubiquitous learning times and empowers the management of distributed e-learning meta-spaces.Facultad de Informátic

Biochemical algorithm to identify individuals with ALPL variants among subjects with persistent hypophosphatasaemia

Hypophosphatasia (HPP) is a rare and underdiagnosed condition characterized by deficient bone and teeth mineralization. The aim of this study was first, to evaluate the diagnostic utility of employing alkaline phosphatase (ALP) threshold levels to identify adults with variants in ALPL among individuals with persistently low ALP levels and second, to determine the value of also including its substrates (serum pyridoxal-5′-phosphate—PLP—and urinary phosphoetanolamine-PEA) for this purpose in order to create a biochemical algorithm that could facilitate the diagnostic work-up of HPP. Results: The study population comprised 77 subjects with persistent hypophosphatasaemia. They were divided into two groups according to the presence (+GT) or absence (−GT) of pathogenic ALPL variants: 40 +GT and 37 −GT. Diagnostic utility measures were calculated for different ALP thresholds and Receiver Operating Characteristic (ROC) curves were employed to determine PLP and PEA optimal cut-off levels to predict the presence of variants. The optimal threshold for ALP was 25 IU/L; for PLP, 180 nmol/L and for PEA, 30 µmol/g creatinine. Biochemical predictive models were assessed using binary logistic regression analysis and bootstrapping machine learning technique and results were then validated. For ALP 180 nmol/L) that when combined, seem to be very useful to identify individuals with ALPL variant