3,010 research outputs found

    Simple renormalizable flavor symmetry for neutrino oscillations

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    The recent measurement of a non-zero neutrino mixing angle θ13\theta_{13} requires a modification of the tri-bimaximal mixing pattern that predicts a zero value for it. We propose a new neutrino mixing pattern based on a spontaneously-broken A4A_{4} flavor symmetry and a type-I seesaw mechanism. Our model allows for approximate tri-bimaximal mixing and non-zero θ13\theta_{13}, and contains a natural way to implement low and high energy CP violation in neutrino oscillations, and leptogenesis with a renormalizable Lagrangian. Both normal and inverted mass hierarchies are permitted within 3σ3\sigma experimental bounds, with the prediction of small (large) deviations from maximality in the atmospheric mixing angle for the normal (inverted) case. Interestingly, we show that the inverted case is excluded by the global analysis in 1σ1\sigma experimental bounds, while the most recent MINOS data seem to favor the inverted case. Our model make predictions for the Dirac CP phase in the normal and inverted hierarchies, which can be tested in near-future neutrino oscillation experiments. Our model also predicts the effective mass mee|m_{ee}| measurable in neutrinoless double beta decay to be in the range 0.04mee0.150.04\lesssim |m_{ee}| \lesssim 0.15 eV for the normal hierarchy and 0.06mee0.110.06\lesssim |m_{ee}| \lesssim 0.11 eV for the inverted hierarchy, both of which are within the sensitivity of the next generation experiments.Comment: 29 pages and 10 figures. No corrections. Version for Phys. Rev.

    Editorial

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    A feral family on our doorstep

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    A family was discovered living in isolation in the Free State region of South Africa. Certain members of this family, (the mother and three sons and a daughter) displayed primitive and ape-like behaviour, prompting the local and international press to refer to them as a feral family. The affected members of the family are presented as a case study describing how the family became isolated, their response to outside intervention and eventually how the family was “discovered”. Clinical presentations are also documented as well as the therapeutic interventions used. After evaluation, the affected members of the family were shown to have various degrees of mental retardation. The words ‘feral' and ‘neglect' are defined and certain similar documented cases of feral children discovered previously in other regions are mentioned. The etiology of the condition is explored, discussing the effects of the environment on various aspects of neural development in children, especially referring to the lack of neuro-stimulation and other insults to the brain during the critical phase of brain plasticity. Cognitive deficits, poor mastery of language and decrease in brain size are often found in feral children. The role of a child's genetic predisposition and a paucity of environmental stimulation is also explained in the article. South African Psychiatry Review Vol. 9(4) 2006: 231-23

    Rift Valley fever virus lacking NSm proteins retains high virulence in vivo and may provide a model of human delayed onset neurologic disease

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    AbstractRift Valley fever virus is a significant human and veterinary pathogen responsible for explosive outbreaks throughout Africa and the Arabian Peninsula. Severe acute disease in humans includes rapid onset hepatic disease and hemorrhagic fever or delayed onset encephalitis. A highly efficient reverse genetics system was developed which allowed generation of recombinant RVF viruses to assess the role of NSm protein in virulence in a rat model in which wild-type RVF virus strain ZH501 (wt-ZH501) results in 100% lethal hepatic disease 2–3 days post infection. While extensive genomic analysis indicates conservation of the NSm coding capability of diverse RVF viruses, and viruses deficient in NSs proteins are completely attenuated in vivo, comparison of wt-ZH501, a reverse genetics generated wt-ZH501 virus (R-ZH501), and R-ZH501 virus lacking the NSm proteins (R-ΔNSm-ZH501) demonstrated that the NSm proteins were nonessential for in vivo virulence and lethality. Surprisingly, while 44% of R-ΔNSm-ZH501 infected animals quickly developed lethal hepatic disease similar to wt- and R-ZH501, 17% developed delayed onset neurologic disease (lethargy, head tremors, and ataxia) at 13 days post infection. Such infections may provide the basis for study of both RVF acute hepatic disease and delayed onset encephalitic disease in humans

    The Las Campanas Distant Cluster Survey -- The Correlation Function

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    We present the first non-local (z>0.2) measurement of the cluster-cluster spatial correlation length, using data from the Las Campanas Distant Cluster Survey (LCDCS). We measure the angular correlation function for velocity-dispersion limited subsamples of the catalog at estimated redshifts of 0.35<z_{est}<0.575, and derive spatial correlation lengths for these clusters via the cosmological Limber equation. The correlation lengths that we measure for clusters in the LCDCS are consistent both with local results for the APM cluster catalog and with theoretical expectations based upon the Virgo Consortium Hubble Volume simulations and the analytic predictions. Despite samples containing over 100 clusters, our ability to discriminate between cosmological models is limited because of statistical uncertainty.Comment: 7 pages, 4 figures, accepted to ApJ (v571, May 20, 2002

    Preparation and Use of Preconstructed Orders, Order Sets, and Order Menus in a Computerized Provider Order Entry System

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    Objective: To describe the configuration and use of the computerized provider order entry (CPOE) system used for inpatient and outpatient care at the authors' facility. Design: Description of order configuration entities, use patterns, and configuration changes in a production CPOE system. Measurements: The authors extracted and analyzed the content of order configuration entities (order dialogs, preconfigured [quick] orders, order sets, and order menus) and determined the number of orders entered in their production order entry system over the previous three years. The authors measured use of these order configuration entities over a six-month period. They repeated the extract two years later to measure changes in these entities. Results: CPOE system configuration, conducted before and after first production use, consisted of preparing 667 order dialogs, 5,982 preconfigured (quick) orders, and 513 order sets organized in 703 order menus for particular contexts, such as admission for a particular diagnosis. Fifty percent of the order dialogs, 57% of the quick orders, and 13% of the order sets were used within a six-month period. Over the subsequent two years, the volume of order configuration entities increased by 26%. Conclusions: These order configuration steps were time-consuming, but the authors believe they were important to increase the ordering speed and acceptability of the order entry software. Lessons learned in the process of configuring the CPOE ordering system are given. Better understanding of ordering patterns may make order configuration more efficient because many of the order configuration entities that were created were not used by clinician

    The thorny way of creating the State bureau of investigations of Ukraine

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    Nichol D. H. The thorny way of creating the State bureau of investigations of Ukraine / D. H. Nichol // Державне бюро розслідувань: на шляху розбудови : матер. Міжнар. наук.-практ. конф. (м. Одеса, 16 червня 2018 р.) / редкол.: Г. О. Ульянова (голова ред.), В. М. Дрьомін, Є. Л. Стрельцов [та ін.] ; НУ "ОЮА". - Одеса : Юридична література, 2018. - С. 32-34

    2-[N-(2,4-Difluoro­phen­yl)carbamo­yl]-3,4,5,6-tetra­fluoro­benzoic acid

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    The title compound, C14H5F6NO3, was synthesized by condensation of tetra­fluoro­phthalic anhydride and 2,4-difluoro­aniline. It was then recrystallized from hexane to give a nonmerohedral twin with two crystallographically unique mol­ecules in the asymmetric unit. The refined twin fraction is 0.460 (3). Torsional differences between the aryl rings and the central amide group account for the presence of two unique mol­ecules. The compound packs as double tapes formed by O—H⋯O and N—H⋯O hydrogen-bonding inter­actions between each unique mol­ecule and its symmetry equivalents

    The Mean and Scatter of the Velocity Dispersion-Optical Richness Relation for maxBCG Galaxy Clusters

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    The distribution of galaxies in position and velocity around the centers of galaxy clusters encodes important information about cluster mass and structure. Using the maxBCG galaxy cluster catalog identified from imaging data obtained in the Sloan Digital Sky Survey, we study the BCG-galaxy velocity correlation function. By modeling its non-Gaussianity, we measure the mean and scatter in velocity dispersion at fixed richness. The mean velocity dispersion increases from 202+/-10 km/s for small groups to more than 854+/-102 km/s for large clusters. We show the scatter to be at most 40.5+/-3.5%, declining to 14.9+/-9.4% in the richest bins. We test our methods in the C4 cluster catalog, a spectroscopic cluster catalog produced from the Sloan Digital Sky Survey DR2 spectroscopic sample, and in mock galaxy catalogs constructed from N-body simulations. Our methods are robust, measuring the scatter to well within one-sigma of the true value, and the mean to within 10%, in the mock catalogs. By convolving the scatter in velocity dispersion at fixed richness with the observed richness space density function, we measure the velocity dispersion function of the maxBCG galaxy clusters. Although velocity dispersion and richness do not form a true mass-observable relation, the relationship between velocity dispersion and mass is theoretically well characterized and has low scatter. Thus our results provide a key link between theory and observations up to the velocity bias between dark matter and galaxies.Comment: 25 pages, 15 figures, 2 tables, published in Ap
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