74 research outputs found

    Analogs of the double-Reissner-Nordstrom solution in magnetostatics and dilaton gravity: mathematical description and some physical properties

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    In this paper we consider a magnetic analog of the double-Reissner-Nordstrom solution and construct the corresponding magnetic potential A_\varphi in the explicit form. The behavior of the resulting solution under the Harrison transformation then naturally singles out the asymmetric black diholes - configurations composed of two non-extreme black holes possessing unequal masses, and charges equal in magnitude but opposite in sign - as its most general subclass for which equilibrium of the black-hole constituents can be achieved with the aid of the external magnetic (or electric) field. We also generalize the double-Reissner-Nordstrom solution to the dilaton gravity with arbitrary dilaton coupling, yielding as the result the 4-dimensional double-Gibbons-Maeda spacetime. The study of some physical properties of the solutions obtained leads, in particular, to very simple formulas for the areas of the horizons and surface gravities.Comment: 18 pages, 1 figure; title changed, typos corrected; a considerably extended version which includes the discussion of the magnetostatic case and the explicit formula for the magnetic potentia

    Evaluación de la reacción de las lineas avanzadas de soya Glycine max (L) Merril frente al patógeno Cylindrocladium scoparium (morgan).

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    El artículo presenta el desarrollo de la investigación con lo cual se pretendía identificar materiales tolerantes para zonas afectadas por la enfermedad. Encontramos la metodología, las variables de sanidad, los métodos de inoculación, los resultados y discusiones, la descripción de los grupos para las variables de sanidad y las conclusiones y recomendaciones.Soya-Soja- Glycine ma

    Técnicas microbiológicas y moleculares para la identificación de Salmonella sp en la industria avícola: una revisión sistemática de alcance

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    A systematic review of the diagnostic methods described in the literature for the identification and characterization of species of the genus Salmonella was carried out. The review was carried out using publications from 2015 to 2021 registered in the NCBI/PubMed, ScienceDirect, Scopus, SciELO, Google Scholar and Springer databases and applying the PRISMA methodology. In total, 61 articles were analysed, grouping the data according to country of origin, type of sample, technique, microbiology protocol and genes used in molecular tests. The microbiology protocols are based on performing pre-enrichment in peptone water and enrichment in tetrathionate (TT) and Rappaport-Vassiliadis (RV) broths, especially with faecal or environmental samples, to subsequently carry out isolations in selective and differential media. The identification of some Salmonella sp serovars that cause disease in poultry is mainly done with molecular techniques such as conventional PCR and multiplex PCR, based on the detection of genes such as invA, hilA, fliC, sefA, spvC, pefA, speC y glgC. Molecular tools are an alternative to traditional microbiology and serotyping techniques with the White-Kauffmann-Le Minor methodology, as they require less time and can identify serovars; however, microbiological tools such as enrichment contribute to the step prior to the use of other diagnostic tools.Se realizó una revisión sistemática de los métodos de diagnóstico descritos en la literatura para la identificación y caracterización de especies del género Salmonella. La revisión se realizó utilizando publicaciones de 2015 a 2021 registradas en las bases de datos de NCBI/PubMed, ScienceDirect, Scopus, SciELO, Google Scholar y Springer, aplicando la metodología PRISMA. Se analizaron 61 artículos, agrupando los datos según el país de origen, tipo de muestra, técnica utilizada, protocolo de microbiología empleado y genes utilizados en las pruebas moleculares. Los protocolos de microbiología se basan en pruebas de pre-enriquecimiento en agua peptonada y enriquecimiento en caldos de tetrationato (TT) y Rappaport-Vassiliadis (RV), especialmente con muestras de heces o muestras ambientales, para posteriormente realizar los aislamientos en medios selectivos y diferenciales. La identificación de algunas serovariedades de Salmonella sp que causan enfermedad en las aves se realiza principalmente con técnicas moleculares (PCR convencional y PCR multiplex), basándose en la detección de genes como invA, hilA, fliC, sefA, spvC, pefA, speC y glgC. Las herramientas moleculares son una alternativa a las técnicas tradicionales de microbiología y serotipificación con la metodología White-Kauffmann–Le Minor, por requerir de menos tiempo y poder identificar a los serovares; sin embargo, las herramientas microbiológicas como el enriquecimiento contribuyen en el paso previo al empleo de otras herramientas diagnósticas

    Science Gateways and AI/ML: How Can Gateway Concepts and Solutions Meet the Needs in Data Science?

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    Science gateways are a crucial component of critical infrastructure as they provide the means for users to focus on their topics and methods instead of the technical details of the infrastructure. They are defined as end-to-end solutions for accessing data, software, computing services, sensors, and equipment specific to the needs of a science or engineering discipline and their goal is to hide the complexity of the underlying infrastructure. Science gateways are often called Virtual Research Environments in Europe and Virtual Labs in Australasia; we consider these two terms to be synonymous with science gateways. Over the past decade, artificial intelligence (AI) and machine learning (ML) have found applications in many different fields in private industry, and private industry has reaped the benefits. Likewise, in the academic realm, large-scale data science applications have also learned to apply public high-performance computing resources to make use of this technology. However, academic and research science gateways have yet to fully adopt the tools of AI. There is an opportunity in the gateways space, both to increase the visibility and accessibility to AI/ML applications and to enable researchers and developers to advance the field of science gateway cyberinfrastructure itself. Harnessing AI/ML is recognized as a high priority by the science gateway community. It is, therefore, critical for the next generation of science gateways to adapt to support the AI/ML that is already transforming many scientific fields. The goal is to increase collaborations between the two fields and to ensure that gateway services are used and are valuable to the AI/ML community. This chapter presents state-of-the-art examples and areas of opportunity for the science gateways community to pursue in relation to AI/ML and some vision of where these new capabilities might impact science gateways and support scientific research

    Mollicutes antibiotic resistance profile and presence of genital abnormalities in couples attending an infertility clinic.

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    OBJECTIVE: The present study aimed to identify Mollicutes infection in the reproductive system. We also examined the microbiological, biochemical, and antimicrobial profiles of Mollicutes infection, which are potentially associated with clinical reproductive abnormalities causing infertility in couples. METHODS: Thirty-seven couples who were attending an infertility clinic were enrolled. Detection of genital mycoplasmas was performed in cervicovaginal samples or male urethral swabs. Microbiological culture and biochemical and antimicrobial profiles were characterized using a Mycoplasma kit. The results were associated with reproductive abnormalities, as assessed by medical specialists from the infertility clinic. RESULTS: Up to 28.3% of all biological samples (n = 74) showed positive cultures. Bacterial isolates were Ureaplasma urealyticum (71.4%), Mycoplasma hominis (9.5%), or coinfections (19%). Most Mollicutes showed significant resistance to fluoroquinolones, macrolides, and tetracycline; and showed susceptibility to doxycycline, josamycin, and pristinamycin. The presence of resistant strains to any antibiotic was significantly associated with genital abnormalities (χ2 test, relative risk = 11.38 [95% confidence interval: 5.8-22.9]), particularly in women. The highest statistical association was found for macrolide-resistant strains. CONCLUSION: The microbiological antibiotic resistance profile is epidemiologically associated with abnormalities of the reproductive system in couples attending an infertility clinic

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset
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