1,296 research outputs found

    Observation of dressed excitonic states in a single quantum dot

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    We report the observation of dressed states of a quantum dot. The optically excited exciton and biexciton states of the quantum dot are coupled by a strong laser field and the resulting spectral signatures are measured using differential transmission of a probe field. We demonstrate that the anisotropic electron-hole exchange interaction induced splitting between the x- and y-polarized excitonic states can be completely erased by using the AC-Stark effect induced by the coupling field, without causing any appreciable broadening of the spectral lines. We also show that by varying the polarization and strength of a resonant coupling field, we can effectively change the polarization-axis of the quantum dot

    Social dialogue during the financial and economic crisis - Results from the ILO/World Bank Inventory using a Boolean analysis on 44 countries

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    Using information collected by the ILO/WB Inventory of policy responses to the financial and economic crisis on 44 countries, this paper identified conditions under which there was a social dialogue response to the financial crisis between 2008 and 2010. For that purpose, they use a particular definition of social dialogue, e.g. the emergence of tripartite national-level agreements or major agreements at the sector level; and rely on a Boolean analysis, e.g. a statistical method to detect relationships between variables, for example between answers to a questionnaire. Based on this definition, 13 out of 44 countries adopted national level agreement or major sector level agreement in formulating their crisis response, including seven in Europe, three in Americas, two in Asia, and one in Africa. Explanatory factors for the emergence of social dialogue include freedom of association, the severity of the crisis, and the strength of trade unions.social dialogue / freedom of association / labour policy / economic recession / economic implication / social implication / survey / methodology / developed countries / developing countries

    Observing CMB polarisation through ice

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    Ice crystal clouds in the upper troposphere can generate polarisation signals at the uK level. This signal can seriously affect very sensitive ground based searches for E- and B-mode of Cosmic Microwave Background polarisation. In this paper we estimate this effect within the ClOVER experiment observing bands (97, 150 and 220 GHz) for the selected observing site (Llano de Chajnantor, Atacama desert, Chile). The results show that the polarisation signal from the clouds can be of the order of or even bigger than the CMB expected polarisation. Climatological data suggest that this signal is fairly constant over the whole year in Antarctica. On the other hand the stronger seasonal variability in Atacama allows for a 50% of clean observations during the dry season.Comment: 7 Pages, 4 figure

    Revealing emergent magnetic charge in an antiferromagnet with diamond quantum magnetometry

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    Whirling topological textures play a key role in exotic phases of magnetic materials and are promising for logic and memory applications. In antiferromagnets, these textures exhibit enhanced stability and faster dynamics with respect to their ferromagnetic counterparts, but they are also difficult to study due to their vanishing net magnetic moment. One technique that meets the demand of highly sensitive vectorial magnetic field sensing with negligible backaction is diamond quantum magnetometry. Here we show that an archetypal antiferromagnet—haematite—hosts a rich tapestry of monopolar, dipolar and quadrupolar emergent magnetic charge distributions. The direct read-out of the previously inaccessible vorticity of an antiferromagnetic spin texture provides the crucial connection to its magnetic charge through a duality relation. Our work defines a paradigmatic class of magnetic systems to explore two-dimensional monopolar physics, and highlights the transformative role that diamond quantum magnetometry could play in exploring emergent phenomena in quantum materials

    The On-Site Analysis of the Cherenkov Telescope Array

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    The Cherenkov Telescope Array (CTA) observatory will be one of the largest ground-based very high-energy gamma-ray observatories. The On-Site Analysis will be the first CTA scientific analysis of data acquired from the array of telescopes, in both northern and southern sites. The On-Site Analysis will have two pipelines: the Level-A pipeline (also known as Real-Time Analysis, RTA) and the level-B one. The RTA performs data quality monitoring and must be able to issue automated alerts on variable and transient astrophysical sources within 30 seconds from the last acquired Cherenkov event that contributes to the alert, with a sensitivity not worse than the one achieved by the final pipeline by more than a factor of 3. The Level-B Analysis has a better sensitivity (not be worse than the final one by a factor of 2) and the results should be available within 10 hours from the acquisition of the data: for this reason this analysis could be performed at the end of an observation or next morning. The latency (in particular for the RTA) and the sensitivity requirements are challenging because of the large data rate, a few GByte/s. The remote connection to the CTA candidate site with a rather limited network bandwidth makes the issue of the exported data size extremely critical and prevents any kind of processing in real-time of the data outside the site of the telescopes. For these reasons the analysis will be performed on-site with infrastructures co-located with the telescopes, with limited electrical power availability and with a reduced possibility of human intervention. This means, for example, that the on-site hardware infrastructure should have low-power consumption. A substantial effort towards the optimization of high-throughput computing service is envisioned to provide hardware and software solutions with high-throughput, low-power consumption at a low-cost.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

    Sífilis congênita e gestacional no Sudeste Brasileiro

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    Objective: To analyse the epidemiologic profile of congenital and gestational syphilis in Southeastern Brazil and to verify factors associated with this disease’s predominance. Methods: This is a descriptive epidemiologic study conducted from January 2010 to December 2019. Secondary data used in this study were obtained from Brazilian Geography and Statistics Institute (IBGE) and Brazilian Ministry of Health (MS). Results: Cases of congenital and gestational syphilis are related to a low educational level, racial minorities and a higher risk of preterm labor due to late presentation to prenatal care. In this study’s interval, we observed an increase in the detection rate and a decrease in the number of stillbirths caused by congenital syphilis. Conclusion: In most years of analysis, there is a growing tendency of cases of syphilis, which are reported mostly during latent and primary stages. The majority of reported cases are associated with racial minorities in a vulnerable condition regarding socioeconomic status and educational level. Furthermore, this study reveals a decrease of abortions and stillbirths, while the death rate of children below one year of age due to complications of congenital syphilis has increased. Keywords: Congenital syphilis; Gestational syphilis; Prenatal care.Objetivo: Analisar o perfil epidemiológico da sífilis congênita e gestacional na região Sudeste e descrever os principais fatores presentes na doença. Método: Trata-se de um estudo epidemiológico, do tipo descritivo, desenvolvido de janeiro de 2010 a dezembro de 2019. Os dados secundários utilizados (epidemiológicos e demográficos) foram obtidos do Sistema de Informação de Agravos de Notificações (SINAN), do Instituto Brasileiro de Geografia e Estatística,  e do Ministério da Saúde (MS) do Brasil. Resultados: Os casos de sífilis gestacional (154.451 casos) e congênita (80 mil casos) estiveram relacionados ao baixo grau de escolaridade materna (49,38%), minorias raciais (58,45%) e maiores fatores de riscos para a prematuridade, associados a adesão tardia ao pré-natal. Além disso, no intervalo de tempo estudado, evidenciou-se um aumento nas taxas de detecção e a diminuição do número de natimortos por sífilis congênita. Conclusões: O estudo mostrou que houve, na maior parte do tempo, uma tendência de crescimento anual dos casos de sífilis, em que a maioria das notificações são feitas no período latente ou primário. A maioria dos casos reportados são de pessoas pretas, pardas ou indígenas, em situação de vulnerabilidade econômica, social e educacional. Houve, também, redução dos casos de abortos e natimortos, porém, um aumento de óbitos de nascidos com menos de 1 ano decorrente de complicações da sífilis congênita. Palavras-chave: Sífilis congênita; Sífilis gestacional; Pré-natal.

    Shear-assisted water-fluxed melting and AFC processes in the foreland of the Early Paleozoic Famatinian orogen: petrogenesis of leucogranites and pegmatites from the Sierras de Córdoba, Argentina

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    In the Comechingones pegmatitic field, central Argentina, leucogranite and pegmatite bodies crop out in a relatively narrow (25 × 10 km) belt, and were emplaced synkinematically with the main deformational event of the crustal-scale Guacha Corral shear zone during the Early Ordovician (~ 475 Ma). These leucogranites and pegmatites are geochemically evolved rocks with high silica and alkalis, low Fe2O3, MgO, TiO2 and CaO, and high ASI values. The leucogranites display quite variable Sr and Nd isotope compositions (initial 87Sr/86Sr ratios from 0.7048 to 0.7170, and εNd values from + 2.0 to − 3.1), some of which do not overlap with almost any other pre-Famatinian rock from the Sierras de Córdoba. The major and trace element geochemistry and the particular Sr and Nd isotope compositions of the leucogranites are here explained by the following processes: (1) water-fluxed partial melting of amphibolites at relatively low P–T conditions generating currently unexposed granodioritic melts with unradiogenic 87Sr/86Sr ratios and radiogenic εNd values; (2) fractionation of mostly plagioclase and monazite leading to compositions close to the leucogranite melts; and (3) assimilation of metasedimentary rocks with crustal isotopic signatures, modelled by assimilation and fractional crystallization processes. The major, trace and isotope compositions of the pegmatites suggest a derivation from partial melting of the same metasedimentary protoliths of the Sierras de Córdoba that were assimilated by leucogranite melts. We propose a feedback relationship among deformation, anatexis, magma evolution and mass transfer in the context of such a crustal-scale shear zone in the foreland of the Famatinian orogen

    No difference in penetrance between truncating and missense/aberrant splicing pathogenic variants in mlh1 and msh2: A prospective lynch syndrome database study

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    Background. Lynch syndrome is the most common genetic predisposition for hereditary cancer. Carriers of pathogenic changes in mismatch repair (MMR) genes have an increased risk of developing colorectal (CRC), endometrial, ovarian, urinary tract, prostate, and other cancers, depending on which gene is malfunctioning. In Lynch syndrome, differences in cancer incidence (penetrance) according to the gene involved have led to the stratification of cancer surveillance. By contrast, any differences in penetrance determined by the type of pathogenic variant remain unknown. Objective. To determine cumulative incidences of cancer in carriers of truncating and missense or aberrant splicing pathogenic variants of the MLH1 and MSH2 genes. Methods. Carriers of pathogenic variants of MLH1 (path_MLH1) and MSH2 (path_MSH2) genes filed in the Prospective Lynch Syndrome Database (PLSD) were categorized as truncating or missense/aberrant splicing according to the InSiGHT criteria for pathogenicity. Results. Among 5199 carriers, 1045 had missense or aberrant splicing variants, and 3930 had truncating variants. Prospective observation years for the two groups were 8205 and 34,141 years, respectively, after which there were no significant differences in incidences for cancer overall or for colorectal cancer or endometrial cancers separately. Conclusion. Truncating and missense or aberrant splicing pathogenic variants were associated with similar average cumulative incidences of cancer in carriers of path MLH1 and path_MSH2.Fil: Dominguez Valentin, Mev. St Mark’s Hospital; Reino Unido. The Norwegian Radium Hospital; Noruega. European Hereditary Tumour Group; Reino UnidoFil: Plazzer, John Paul. St Mark’s Hospital; Reino Unido. The Royal Melbourne Hospital; AustraliaFil: Sampson, Julian R.. European Hereditary Tumour Group; Reino Unido. Cardiff University; Reino UnidoFil: Engel, Christoph. European Hereditary Tumour Group; Reino Unido. Universitat Leipzig; AlemaniaFil: Aretz, Stefan. Universitat Bonn; AlemaniaFil: Jenkins, Mark A.. University of Melbourne; AustraliaFil: Sunde, Lone. Aalborg University; DinamarcaFil: Bernstein, Inge. Aalborg University; DinamarcaFil: Capella, Gabriel. European Hereditary Tumour Group; Reino Unido. St Mark’s Hospital; Reino Unido. Institut Català d’Oncologia; EspañaFil: Balaguer Prunés, Francesc. Universidad de Barcelona; EspañaFil: Macrae, Finlay. European Hereditary Tumour Group; Reino Unido. The Royal Melbourne Hospital; AustraliaFil: Winship, Ingrid M.. University of Melbourne; AustraliaFil: Thomas, Huw. Imperial College London; Reino UnidoFil: Evans, Dafydd Gareth. University of Manchester; Reino UnidoFil: Burn, John. Universidad de Newcastle; Australia. The Royal Melbourne Hospital; Australia. St Mark’s Hospital; Reino UnidoFil: Greenblatt, Marc. University of Vermont; Estados UnidosFil: de Vos tot Nederveen Cappel, Wouter H.. Isala Clinics; Países BajosFil: Sijmons, Rolf H.. University of Groningen; Países Bajos. St Mark’s Hospital; Reino Unido. European Hereditary Tumour Group; Reino UnidoFil: Nielsen, Maartje. Leids Universitair Medisch Centrum; Países BajosFil: Bertario, Lucio. Fondazione IRCCS Istituto Nazionale dei Tumori; ItaliaFil: Bonanni, Bernardo. Fondazione IRCCS Istituto Nazionale dei Tumori; ItaliaFil: Tibiletti, Maria Grazia. Università dell’Insubria; ItaliaFil: Cavestro, Giulia Martina. Vita-Salute San Raffaele University; ItaliaFil: Lindblom, Annika. Karolinska Huddinge Hospital; SueciaFil: Della Valle, Adriana. Hospital Fuerzas Armadas; UruguayFil: Lopez Kostner, Francisco. Clínica Universidad de los Andes; ChileFil: Alvarez, Karin. Clínica Universidad de los Andes; ChileFil: Gluck, Nathan. Universitat Tel Aviv; IsraelFil: Katz, Lior. Sheba Medical Center; IsraelFil: Heinimann, Karl. University Hospital Basel; SuizaFil: Piñero, Tamara Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional e Ingeniería Biomédica - Hospital Italiano. Instituto de Medicina Traslacional e Ingeniería Biomédica.- Instituto Universitario Hospital Italiano de Buenos Aires. Instituto de Medicina Traslacional e Ingeniería Biomédica; ArgentinaFil: Pavicic, Walter Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional e Ingeniería Biomédica - Hospital Italiano. Instituto de Medicina Traslacional e Ingeniería Biomédica.- Instituto Universitario Hospital Italiano de Buenos Aires. Instituto de Medicina Traslacional e Ingeniería Biomédica; Argentin
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