89 research outputs found
Adversarial domain adaptation to reduce sample bias of a high energy physics classifier
We apply adversarial domain adaptation to reduce sample bias in a
classification machine learning algorithm. We add a gradient reversal layer to
a neural network to simultaneously classify signal versus background events,
while minimising the difference of the classifier response to a background
sample using an alternative MC model. We show this on the example of simulated
events at the LHC with signal versus background
classification.Comment: 15 pages, 8 figures, to be submitted to JINS
Comparison of NF-kB Regulation in Naive and Anergic Primary CD8+ T Lymphocytes
Due to the cytotoxic potential of CD8+ T cells, maintenance of CD8+ tolerance is critical. A major mechanism of peripheral tolerance in T lymphocytes is the induction of anergy, a refractory state caused by T lymphocyte activation in the absence of costimulation. Hallmarks of anergy are decreased IL-2 secretion and decreased proliferation. Here we used a T cell receptor transgenic mouse model to determine whether there are defects in the NF-κB signaling pathway in CD8+ T lymphocytes rendered anergic in vivo. In the anergic cell population, decreased NF-κB-mediated gene transcription and NF-κB p65 subunit DNA binding activity were observed. These changes were not due to inhibition of early NF-κB activation events, including IκBα degradation and NF-κB p65 subunit nuclear translocation, which occurred normally in anergic T lymphocytes. Nor were they related to defective phosphorylation of p65 at Ser536 in the cytoplasm or Ser276 in the nucleus, as p65 was phosphorylated at these residues in both naïve and anergic T lymphocytes with similar kinetics. However, the anergic CD8+ lymphocytes failed both to phosphorylate the NF-κB p65 subunit at Ser311 an event implicated in the recruitment of histone acetyl-transferase molecules such as CBP and p300, and to acetylate p65 at Lys310. Both of these posttranslational modifications have been shown to be critical for the positive regulation of NF-κB transcriptional activity. Thus, our results suggest that defects in key phosphorylation and acetylation events in p65 underlie defective NF-κB transactivation capacity and resultant lack of T cell function observed in anergic CD8+ T lymphocytes. Taken together these data provide a novel mechanistic explanation of how NF-κB p65 subunit is regulated in anergic CD8+T lymphocytes leading to defective NF-κB transcriptional activity and suggest that recruitment of CBP/p300 and p65 DNA binding in vivo is abrogated in anergic T lymphocytes
Low-temperature Fabrication Process for Integrated High-Aspect Ratio Metal Oxide Nanostructure Semiconductor Gas Sensors
This work presents a new low-temperature fabrication process of metal oxide nanostructures that allows high-aspect ratio zinc oxide (ZnO) and titanium dioxide (TiO2) nanowires and nanotubes to be readily integrated with microelectronic devices for sensor applications. This process relies on a new method of forming a close-packed array of self-assembled high-aspect-ratio nanopores in an anodized aluminum oxide (AAO) template in a thin (2.5 µm) aluminum film deposited on a silicon and lithium niobate substrate (LiNbO3). This technique is in sharp contrast to traditional free-standing thick film methods and the use of an integrated thin aluminum film greatly enhances the utility of such methods. We have demonstrated the method by integrating ZnO nanowires, TiO2 nanowires, and multiwall TiO2 nanotubes onto the metal gate of a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), and the delay line of a surface acoustic wave (SAW) device to form an integrated ChemFET (Chemical Field-Effect Transistor) and a orthogonal frequency coded (OFC) SAW gas sensor. The resulting metal oxide nanostructures of 1-1.7 µm in height and 40-100 nm in diameter offer an increase of up to 220X the surface area over a standard flat metal oxide film for sensing applications.
The metal oxide nanostructures were characterized by SEM, EDX, TEM and Hall measurements to verify stoichiometry, crystal structure and electrical properties. Additionally, the electrical response of ChemFETs and OFC SAW gas sensors with ZnO nanowires, TiO2 nanowires, and multiwall TiO2 nanotubes were measured using 5-200 ppm ammonia as a target gas at room temperature (24ºC) showing high sensitivity and reproducible testing results
Extinct or extant? A new species of \u3ci\u3eTermitodius\u3c/i\u3e Wasmann, 1894, (Coleoptera: Scarabaeidae: Aphodiinae: Rhyparini) with a short review of the genus
A new species of Termitodius Wasmann (Coleoptera: Scarabaeidae: Aphodiinae: Rhyparini) is described from Colombia, Termitodius woodruffi Skelley, Clavijo-Bustos, and Keller, new species. This species is both extant and abundantly preserved in copal. The genus Termitodius is reviewed with a key and brief accounts to all species.
Una nueva especie de Termitodius Wasmann (Coleoptera: Scarabaeidae: Aphodiinae: Rhyparini) es descrita de Colombia, Termitodius woodruffi Skelley, Clavijo-Bustos, y Keller, nueva especie. Esta especie es existente y abundantemente preservada en copal. El género Termitodius es revisado con una clave y reseñas breves para todas las especies.
The pantropical tribe Rhyparini is represented in the Neotropical region by six genera and 25 species. Of these six genera, only one genus, Rhyparus Westwood, is distributed both in the eastern and western hemispheres, the remaining five are exclusively from America (Schoolmeesters 2021; Skelley 2021a, b). The genus Termitodius Wasmann was described in 1894 for a new species from Venezuela (Wasmann 1894). Since then, the only taxonomic treatments were the description of two new species 40 years ago (Reyes-Castillo and Martínez 1979) and its generic delimitation (Skelley 2007).
Though more than 30 fossil species of Aphodiinae are known from the Mesozoic and Tertiary period of the Cenozoic Era, none belong to the tribe Rhyparini nor to the Neotropical region (Krell 2007). Most of the described Neotropical Scarabaeoidea fossils are preserved in amber from the Dominican Republic (e.g., Ratcliffe and Ocampo 2001; Ocampo 2002, 2006; Woodruff 2009; Poinar 2014). Members of the Rhyparini have been documented in Dominican amber (Wu 1996; Poinar and Poinar 1999; Krell 2007) that were recently described (Skelley 2021a, b). Other insects in the New World were described from more recent resin deposits like Colombian copal. However, the age of Colombian pieces lack consensus, with the current trend attributing it to the Cenozoic quaternary period (e.g., Hinojosa-Díaz and Engel 2007; Azar et al. 2009; Penney et al. 2013a; Poinar et al. 2017). Also, it is curious that many described species from copal inclusions are considered to be extant species, yet remain to be discovered as living specimens (Penney et al. 2013b).
The earliest published report that identifies the Colombian copal specimens as Termitodius is by Penney and Green (2011), who called it a “subfossil”. However, Robert Woodruff began working on this new species in the early 2000s, but declining health and other events forced the project to be postponed. After deciding to describe this species to honor Woodruff, PES studied available modern specimens to document unreported specimens of all species in this rare genus. He borrowed a specimen identified by P. Reyes as “T. coronatus” from Colombia, that was later identified as a new species by O. L. Cartwright. Close examination found it to be most similar to the copal specimens in morphology and distribution, and not T. coronatus. This led to the following generic review and species description
DISEÑO E IMPLEMENTACIÓN DE UN PROTOTIPO DE SERVIDOR ELEARNING CON MOODLE PORTABLE CON INTERFAZ WEB MEDIANTE USO DE HARDWARE Y SOFTWARE LIBRE
El proyecto es un prototipo e-learning móvil, para complementar la interacción entre el maestro y sus estudiantes de una forma dinámica, llamativa, de modo que incentive al alumno que ponga un mayor interés en el proceso de aprendizaje. Para la realización de la plataforma se utilizaron diferentes tecnologías de libre distribución. El prototipo está formado por un enrutador inalámbrico casero, un mini computador y una aplicación web de software libre permitiendo la interactividad de forma digital entre el estudiante y el maestro en el aula de clase. El producto puede abastecer una gran cantidad de usuarios conectados al mismo tiempo, con lo cual se pensó en un hardware lo
suficientemente capaz de suplir todas estas necesidades, pero que a su vez no pierda esa movilidad. El equipo permite que el maestro pueda realizar diferentes actividades mediante la aplicación web sin necesidad de contar con acceso a internet y lo pueda utilizar en sus diferentes cursos, el equipo está desarrollado en un ambiente donde tanto su sistema operativo como sus aplicativos son totalmente gratuitos y no infringen con ninguna ley, el proyecto se centra en que los estudiantes se integren más al uso de recursos informáticos para su desempeño académico como herramientas de aprendizaje. La facilidad y la movilidad que ofrece este dispositivo es algo novedoso y rompe el clásico esquema que
se tenía acerca de un aula virtual, en el cual una persona que tenga los amplios conocimientos informáticos era la única persona que tenía acceso a la administración del aplicativo, con este proyecto nos enfocamos en que el propio usuario cree y administre su aula virtualThe project is a prototype mobile e-learning, to complement the interaction between teacher and students in a dynamic, eye-catching way, so that you encourage the student who put a greater in terest in the learning process. Different free distribution technologies were used for the realization of the platform. The prototype consists of a home wireless router, a mini computer and a web pplication of free software allowing interactivity digitally between the student and the teacher in the classroom. The product can provide a large number of users connected at the same time, whichwas thought in hardware sufficiently able to meet all these needs, but which at the same time don't miss that
mobility. The equipment allows teacher can perform different activities through the web application without having internet accessand can use it in their different courses, equipment is developed in an environment where both y our operating system and its applications are completely free of charge and does not infringe any law, the project focuses on that students be more integrated into the use of computing resources for their academic performance as learning tools. Ease and
mobility offered by this device is something novel and breaks the classical scheme that had about a virtual classroom, in which a person having computer knowledge was the only person who had access to the administration of the application, with this projectwe focus on the user to create and manage your virtual classroo
Análisis, diseño y desarrollo de un sitio E-Commerce de productos personalizables utilizando herramientas de desarrollo 3D para los emprendimientos de Tigua Picture y Biocomfy.
El desarrollo de este proyecto procura mejorar la visualización, personalización del producto en el e-commerce, utilizando librerías de uso libre dedicadas al desarrollo para aplicaciones web y de visualización 3D en el navegador, estas herramientas tienen compatibilidad con varios navegadores, es compatible con todos los elementos estándar html y tiene gráficos 3D acelerados que utilizan CPU y GPU del cliente. La presentación 3D de un producto mostrado en el e-commerce facilita la toma de decisiones de compra por parte del cliente, se puede realizar cambios fácilmente en el diseño del producto.The development of this project seeks to improve the visualization, personalization of the product in the ecommerce, using libraries of free use dedicated to the development for web applications and 3D visualization in the browser, these tools have compatibility with several browsers, it is sharable with all the elements standard html and has accelerated 3D graphics that use the client's CPU and GPU. The 3D presentation of a product shown in the ecommerce facilitates the purchase decision making by the customer, you can easily make changes in the design of the product
Upstream dam impacts on gilded catfish Brachyplatystoma rousseauxii (Siluriformes: Pimelodidae) in the Bolivian Amazon
This paper explores the effects of two run-of-river dams (Jirau and Santo Antônio) built in cascade in the middle Madeira River (Brazil) on the interruption of long-distance migration routes of the gilded catfish (Brachyplatystoma rousseauxii). A participative monitoring system was set up to compare capture by commercial fishers approximately 1500 km upstream ofthe dams in Bolivia, before (1998-2007) and after (2015-2017) dam closure. A significant decrease in gilded catfish catches and in catch per unit effort was observed after dam closure, whereas no significant difference in mean weight was found. Back-estimation of age suggests that the few individuals remaining after dam closure in 2009 are a mixture of old homers that returned upstream before dam closure, and residents hatched after dam closure and trapped in the upper Madeira. Unless fishways in the Madeira River dams improve their efficiency, the gilded catfish might become rare and in danger of regional extinction in the upper Madeira basin in the next few years, negatively affecting river fisheries.Fil: Van Damme, Paul A.. Instituto de Investigación Aplicada de Recursos Acuáticos; Bolivia. Universidad Mayor de San Simón; BoliviaFil: Córdova Clavijo, Leslie. Instituto de Investigación Aplicada de Recursos Acuáticos; BoliviaFil: Baigún, Claudio Rafael M.. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Hauser, Marilia. Universidade Federal de Rondônia; Brasil. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; FranciaFil: da Costa Doria, Carolina R.. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; Francia. Universidade Federal de Rondônia; BrasilFil: Duponchelle, Fabrice. Universidade Federal de Rondônia; Brasi
Analysis of the recombination landscape of hexaploid bread wheat reveals genes controlling recombination and gene conversion frequency
Background: Sequence exchange between homologous chromosomes through crossing over and gene conversion is highly conserved among eukaryotes, contributing to genome stability and genetic diversity. A lack of recombination limits breeding efforts in crops; therefore, increasing recombination rates can reduce linkage drag and generate new genetic combinations. Results: We use computational analysis of 13 recombinant inbred mapping populations to assess crossover and gene conversion frequency in the hexaploid genome of wheat (Triticum aestivum). We observe that high-frequency crossover sites are shared between populations and that closely related parents lead to populations with more similar crossover patterns. We demonstrate that gene conversion is more prevalent and covers more of the genome in wheat than in other plants, making it a critical process in the generation of new haplotypes, particularly in centromeric regions where crossovers are rare. We identify quantitative trait loci for altered gene conversion and crossover frequency and confirm functionality for a novel RecQ helicase gene that belongs to an ancient clade that is missing in some plant lineages including Arabidopsis. Conclusions: This is the first gene to be demonstrated to be involved in gene conversion in wheat. Harnessing the RecQ helicase has the potential to break linkage drag utilizing widespread gene conversions
Compartir los datos de investigación en ciencia: introducción al data sharing
The emergence in the scientific community of an initiative known as data sharing, consisting of sharing research data among researchers and aiming to maximize efforts and resources, is analysed. First, the concept of research data and the related technical difficulties depending on the discipline are reviewed. We also examine the motivations, origins and growth of this movement, which has had an important impact on the scientific community’s behaviour through the creation of reposi- tories and data banks, raising both technical and social challenges. Then we discuss leading funding agencies’ initiatives and scientific journals’ editorial policies promoting these practices. Finally, we examine the impact these major changes in researchers’ habits have for librarians, including the emergence of new professional profiles
An improved assembly and annotation of the allohexaploid wheat genome identifies complete families of agronomic genes and provides genomic evidence for chromosomal translocations
Advances in genome sequencing and assembly technologies are generating many high-quality genome sequences, but assemblies of large, repeat-rich polyploid genomes, such as that of bread wheat, remain fragmented and incomplete. We have generated a new wheat whole-genome shotgun sequence assembly using a combination of optimized data types and an assembly algorithm designed to deal with large and complex genomes. The new assembly represents >78% of the genome with a scaffold N50 of 88.8 kb that has a high fidelity to the input data. Our new annotation combines strand-specific Illumina RNA-seq and Pacific Biosciences (PacBio) full-length cDNAs to identify 104,091 high-confidence protein-coding genes and 10,156 noncoding RNA genes. We confirmed three known and identified one novel genome rearrangements. Our approach enables the rapid and scalable assembly of wheat genomes, the identification of structural variants, and the definition of complete gene models, all powerful resources for trait analysis and breeding of this key global crop
- …