86 research outputs found

    Do children with uncomplicated severe acute malnutrition need antibiotics? A systematic review and meta-analysis.

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    Current (1999) World Health Organization guidelines recommend giving routine antibiotics (AB) for all children with severe acute malnutrition (SAM), even if they have uncomplicated disease with no clinically obvious infections. We examined the evidence behind this recommendation

    Polynomial scaling approximations and dynamic correlation corrections to doubly occupied configuration interaction wave functions

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    A class of polynomial scaling methods that approximate Doubly Occupied Configuration Interaction (DOCI) wave functions and improve the description of dynamic correlation is introduced. The accuracy of the resulting wave functions is analysed by comparing energies and studying the overlap between the newly developed methods and full configuration interaction wave functions, showing that a low energy does not necessarily entail a good approximation of the exact wave function. Due to the dependence of DOCI wave functions on the single-particle basis chosen, several orbital optimisation algorithms are introduced. An energy-based algorithm using the simulated annealing method is used as a benchmark. As a computationally more affordable alternative, a seniority number minimising algorithm is developed and compared to the energy based one revealing that the seniority minimising orbital set performs well. Given a well-chosen orbital basis, it is shown that the newly developed DOCI based wave functions are especially suitable for the computationally efficient description of static correlation and to lesser extent dynamic correlation.Fil: Van Raemdonck, Mario. Ghent University; BélgicaFil: Alcoba, Diego Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Poelmans, Ward. Ghent University; BélgicaFil: De Baerdemacker, Stijn. Ghent University; BélgicaFil: Torre, Alicia. Universidad del País Vasco; EspañaFil: Lain, Luis. Universidad del País Vasco; EspañaFil: Massaccesi, Gustavo Ernesto. Universidad de Barcelona. Facultad de Física. Departamento de Física Fomental; EspañaFil: Van Neck, D.. Ghent University; BélgicaFil: Bultinck, P.. Ghent University; Bélgic

    A study of the partitioning of the first-order reduced density matrix according to the theory of atoms in molecules

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    This work describes a simple spatial decomposition of the first-order reduced density matrix corresponding to an N -electron system into first-order density matrices, each of them associated to an atomic domain defined in the theory of atoms in molecules. A study of the representability of the density matrices arisen from this decomposition is reported and analyzed. An appropriate treatment of the eigenvectors of the matrices defined over atomic domains or over unions of these domains allows one to describe satisfactorily molecular properties and chemical bondings within a determined molecule and among its fragments. Numerical determinations, performed in selected molecules, confirm the reliability of our proposal. © 2005 American Institute of Physics.Fil:Bochicchio, R.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

    Evolution, geographic spreading, and demographic distribution of Enterovirus D68.

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    Worldwide outbreaks of enterovirus D68 (EV-D68) in 2014 and 2016 have caused serious respiratory and neurological disease. We collected samples from several European countries during the 2018 outbreak and determined 53 near full-length genome ('whole genome') sequences. These sequences were combined with 718 whole genome and 1,987 VP1-gene publicly available sequences. In 2018, circulating strains clustered into multiple subgroups in the B3 and A2 subclades, with different phylogenetic origins. Clusters in subclade B3 emerged from strains circulating primarily in the US and Europe in 2016, though some had deeper roots linking to Asian strains, while clusters in A2 traced back to strains detected in East Asia in 2015-2016. In 2018, all sequences from the USA formed a distinct subgroup, containing only three non-US samples. Alongside the varied origins of seasonal strains, we found that diversification of these variants begins up to 18 months prior to the first diagnostic detection during a EV-D68 season. EV-D68 displays strong signs of continuous antigenic evolution and all 2018 A2 strains had novel patterns in the putative neutralizing epitopes in the BC- and DE-loops. The pattern in the BC-loop of the USA B3 subgroup had not been detected on that continent before. Patients with EV-D68 in subclade A2 were significantly older than patients with a B3 subclade virus. In contrast to other subclades, the age distribution of A2 is distinctly bimodal and was found primarily among children and in the elderly. We hypothesize that EV-D68's rapid evolution of surface proteins, extensive diversity, and high rate of geographic mixing could be explained by substantial reinfection of adults. Better understanding of evolution and immunity across diverse viral pathogens, including EV-D68 and SARS-CoV-2, is critical to pandemic preparedness in the future

    Entanglement Measures for Single- and Multi-Reference Correlation Effects

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    Electron correlation effects are essential for an accurate ab initio description of molecules. A quantitative a priori knowledge of the single- or multi-reference nature of electronic structures as well as of the dominant contributions to the correlation energy can facilitate the decision regarding the optimum quantum chemical method of choice. We propose concepts from quantum information theory as orbital entanglement measures that allow us to evaluate the single- and multi-reference character of any molecular structure in a given orbital basis set. By studying these measures we can detect possible artifacts of small active spaces.Comment: 14 pages, 4 figure

    Nationwide genetic analysis of more than 600 families with inherited eye diseases in Argentina

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    This study corresponds to the first large-scale genetic analysis of inherited eye diseases (IED) in Argentina and describes the comprehensive genetic profile of a large cohort of patients. Medical records of 22 ophthalmology and genetics services throughout 13 Argentinian provinces were analyzed retrospectively. Patients with a clinical diagnosis of an ophthalmic genetic disease and a history of genetic testing were included. Medical, ophthalmological and family history was collected. A total of 773 patients from 637 families were included, with 98% having inherited retinal disease. The most common phenotype was retinitis pigmentosa (RP, 62%). Causative variants were detected in 379 (59%) patients. USH2A, RPGR, and ABCA4 were the most common disease-associated genes. USH2A was the most frequent gene associated with RP, RDH12 early-onset severe retinal dystrophy, ABCA4 Stargardt disease, PROM1 cone-rod dystrophy, and BEST1 macular dystrophy. The most frequent variants were RPGR c.1345 C > T, p.(Arg449*) and USH2A c.15089 C > A, p.(Ser5030*). The study revealed 156/448 (35%) previously unreported pathogenic/likely pathogenic variants and 8 possible founder mutations. We present the genetic landscape of IED in Argentina and the largest cohort in South America. This data will serve as a reference for future genetic studies, aid diagnosis, inform counseling, and assist in addressing the largely unmet need for clinical trials to be conducted in the region

    First isolation of Histoplasma capsulatum from the urban bat Eumops bonariensis

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    Fil: Canteros, C. E. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de MicologĂ­a; Argentina.Fil: Iachini, R. H. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Rivas, M. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de MicologĂ­a; Argentina.Fil: Vaccaro, O. Museo Argentino de Ciencias Naturales Bernardino Rivadavia; Argentina.Fil: Madariaga, J. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Galarza, R. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Snaiderman, L. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: MartĂ­nez, M. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Paladino, M. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Cicuttin, G. Instituto Municipal de Zoonosis Luis Pasteur; Argentina.Fil: Varela, E. Museo Argentino de Ciencias Naturales Bernardino Rivadavia; Argentina.Fil: Alcoba, E. Hospital Municipal de OncologĂ­a Marie Curie; Argentina.Fil: Zuiani, F. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de MicologĂ­a; Argentina.Fil: Sahaza, J. H. UNAM. Departamento de MicrobiologĂ­a y ParasitologĂ­a; MĂ©xico.Fil: Taylor, M. L. UNAM. Departamento de MicrobiologĂ­a y ParasitologĂ­a; MĂ©xico.Fil: Davel, Graciela Odelsia. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de MicologĂ­a; Argentina.Se comunica el primer aislamiento de Histoplasma capsulatum var. capsulatum de un murciĂ©lago macho de la especie Eumops bonariensis, capturado en la ciudad de Buenos Aires en 2003. Los aislamientos fueron recuperados de bazo e hĂ­gado e identificados fenotĂ­picamente. Se los comparĂł por PCR, con 17 aislamientos clĂ­nicos, 12 de pacientes residentes en la ciudad de Buenos Aires y cinco de otros paĂ­ses de AmĂ©rica, usando los iniciadores 1283, (GTG)5, (GACA)4 y M13. Con los cuatro iniciadores, los perfiles de los aislamientos de murciĂ©lago resultaron idĂ©nticos entre sĂ­ y mĂĄs relacionados a los de pacientes de Buenos Aires que a los de otros paĂ­ses (porcentaje de similitud: 91-100% y 55- 87%, respectivamente). La alta relaciĂłn genĂ©tica entre los aislamientos obtenidos del murciĂ©lago y de los humanos residentes en Buenos Aires sugiere una fuente comĂșn de infecciĂłn. Este es el primer registro de E. bonariensis infectado con H. capsulatum en el mundo, y el primer aislamiento del hongo en la poblaciĂłn de quirĂłpteros de la Argentina. AsĂ­ como estos mamĂ­feros actĂșan como reservorio y dispersan el hongo en la naturaleza, la infecciĂłn en murciĂ©lagos urbanos podrĂ­a asociarse al elevado nĂșmero de casos de histoplasmosis entre pacientes inmunodeprimidos en la ciudad de Buenos Aires

    Citizen science and online data: Opportunities and challenges for snake ecology and action against snakebite

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    The secretive behavior and life history of snakes makes studying their biology, distribution, and the epidemiology of venomous snakebite challenging. One of the most useful, most versatile, and easiest to collect types of biological data are photographs, particularly those that are connected with geographic location and date-time metadata. Photos verify occurrence records, provide data on phenotypes and ecology, and are often used to illustrate new species descriptions, field guides and identification keys, as well as in training humans and computer vision algorithms to identify snakes. We scoured eleven online and two offline sources of snake photos in an attempt to collect as many photos of as many snake species as possible, and attempt to explain some of the inter-species variation in photograph quantity among global regions and taxonomic groups, and with regard to medical importance, human population density, and range size. We collected a total of 725,565 photos—between 1 and 48,696 photos of 3098 of the world's 3879 snake species (79.9%), leaving 781 “most wanted” species with no photos (20.1% of all currently-described species as of the December 2020 release of The Reptile Database). We provide a list of most wanted species sortable by family, continent, authority, and medical importance, and encourage snake photographers worldwide to submit photos and associated metadata, particularly of “missing” species, to the most permanent and useful online archives: The Reptile Database, iNaturalist, and HerpMapper.ISSN:2590-171
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