251 research outputs found

    Царський і республіканський Рим в антикознавчих дослідженнях М.П. Драгоманова

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    У статті розглянуто особливості вивчення та рецепції римської історії VIII–I ст. до н. е. в антикознавчих студіях М. Драгоманова. Зроблено висновок, що дослідження М. Драгоманова з історії Риму вплинули на формування наукових і суспільно-політичних поглядів вченого, а також Лесі Українки та І. Франка.In the article peculiarities of study and reception of Roman history VIII–I centuries B.C. in M. Drahomanov’s classical researches are highlighted. The author concludes that M. Drahomanov’s Roman classical studies influenced on formation of scientific and political views of M. Drahomanov, Lesya Ukrainka, I. Franko

    Schools and education

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    Children in the North are more likely to live in poverty than those in the rest of England – and increasingly so. Poverty is the lead driver of inequalities between children in the North and their counterparts in the rest of the country, leading to worse physical and mental health outcomes, educational attainment, and lower lifelong economic productivity. The COVID-19 pandemic has made this situation worse. Although the full impact is not yet known, modelling suggests that, without intervention, the outlook is bleak. To address the North-South productivity gap we must tackle the stark inequalities evidenced in this report, put in place a child-first place-based recovery plan, and enable the children of the North to fulfil their potential

    First Observations of Long-Lived Meteor Trains with Resonance Lidar and Other Optical Instruments

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    In November 1998 the earth passed through a maximum in the cometary material responsible for the yearly Leonids meteor shower. The meteor storm event produced numerous examples of long-lived chemiluminescent trails--visible to the naked eye over New Mexico, where a major observation campaign was centered. One trail was detected for over an hour with a CCD camera employing a narrow sodium filter, and many others were observed for over ten minutes each. For the first time, sodium densities in such trails were measured while also being imaged in sodium light. We have verified one source of long-lived light emissions--a sodium-catalyzed reaction involving ozone--but it is far too weak to explain the visibility of such trails. In addition, we present a new explanation for the cylindrical shell appearance long reported for chemiluminescent trails and show that ozone depletion by chemical processes is a possible explanation for this phenomenon

    Stability and diffusion of Hg implanted YBa2_{2}Cu3_{3}O6+x_{6+x}

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    The radioactive isotope 197m^{197m}Hg was implanted at 60 keV with low fluences (1013^{13} ions/cm2^{2} ) into YBa2_{2}Cu3_{3}O6+x_{6+x} (YBCO) superconducting thin films at ISOLDE/CERN. We report on the Hg dynamics and stability inside the YBCO lattice as a function of annealing temperature up to 890 K in vacuum or O2_{2} atmosphere. The perturbed angular correlation (PAC) technique was used for probing the Hg behavior at the atomic scale, while by monitoring the sample's activity in situ the Hg outdiffusion was studied. We found that Hg ions occupy unique lattice sites and that Hg should be bound to two apical oxygens. Hg diffusion occurs only for annealing temperatures above 653 K, in vacuum. The Hg migration energy was estimated to be EM = 1.58 ±\pm 0.15 eV

    Stability studies of Hg implanted YBa2_{2}Cu3_{3}O6+x_{6+x}

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    High quality YBa2_{2}Cu3_{3}O6+x_{6+x} (YBCO) superconducting thin films were implanted with the radioactive 197m^{197m}Hg (T1/2_{1/2} = 24 h) isotope to low fluences of 1013^{13} atoms/cm2^{2} and 60 keV energy. The lattice location and stability of the implanted Hg were studied combining the Perturbed Angular Correlation (PAC) and Emission Channeling (EC) techniques. We show that Hg can be introduced into the YBCO lattice by ion implantation into unique regular sites. The EC data show that Hg is located on a highly symmetric site on the YBCO lattice, while the PAC data suggests that Hg occupies the Cu(1) site. Annealing studies were performed under vacuum and O2_{2} atmosphere and show that Hg starts to diffuse only above 653 K

    Cytomegaloviral determinants of CD8+ T cell programming and RhCMV/SIV vaccine efficacy

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    Simian immunodeficiency virus (SIV) insert-expressing, 68–1 Rhesus Cytomegalovirus (RhCMV/SIV) vectors elicit major histocompatibility complex (MHC)-E- and -II-restricted, SIV-specific CD8(+) T cell responses, but the basis of these unconventional responses and their contribution to demonstrated vaccine efficacy against SIV challenge in the rhesus monkeys (RMs) has not been characterized. We show that these unconventional responses resulted from a chance genetic rearrangement in 68–1 RhCMV that abrogated the function of eight distinct immunomodulatory gene products encoded in two RhCMV genomic regions (Rh157.5/Rh157.4 and Rh158–161), revealing three patterns of unconventional response inhibition. Differential repair of these genes with either RhCMV-derived or orthologous human CMV (HCMV)-derived sequences (UL128/UL130; UL146/UL147) leads to either of two distinct CD8(+) T cell response types – MHC-Ia-restricted-only, or a mix of MHC-II- and MHC-Ia-restricted CD8(+) T cells. Response magnitude and functional differentiation are similar to RhCMV 68–1, but neither alternative response type mediated protection against SIV challenge. These findings implicate MHC-E-restricted CD8(+) T cell responses as mediators of anti-SIV efficacy and indicate that translation of RhCMV/SIV vector efficacy to humans will likely require deletion of all genes that inhibit these responses from the HCMV/HIV vector

    Sampling frequency affects estimates of annual nitrous oxide fluxes

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    Quantifying nitrous oxide (N2O) fluxes, a potent greenhouse gas, from soils is necessary to improve our knowledge of terrestrial N2O losses. Developing universal sampling frequencies for calculating annual N2O fluxes is difficult, as fluxes are renowned for their high temporal variability. We demonstrate daily sampling was largely required to achieve annual N2O fluxes within 10% of the "best" estimate for 28 annual datasets collected from three continents - Australia, Europe and Asia. Decreasing the regularity of measurements either under- or overestimated annual N2O fluxes, with a maximum overestimation of 935%. Measurement frequency was lowered using a sampling strategy based on environmental factors known to affect temporal variability, but still required sampling more than once a week. Consequently, uncertainty in current global terrestrial N2O budgets associated with the upscaling of field-based datasets can be decreased significantly using adequate sampling frequencies
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