179 research outputs found

    Study of Zγ events and limits on anomalous ZZγ and Zγγ couplings in pp̄ collisions at s=1.96TeV

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    We present a measurement of the Zγ production cross section and limits on anomalous ZZγ and Zγγ couplings for form-factor scales of Λ=750 and 1000 GeV. The measurement is based on 138 (152) candidates in the eeγ (μμγ) final state using 320(290)pb-1 of pp̄ collisions at s=1.96TeV. The 95% C.L. limits on real and imaginary parts of individual anomalous couplings are |h10,30Z|<0.23, |h20,40Z|<0.020, |h10,30γ|<0.23, and |h20,40γ|<0.019 for Λ=1000GeV. © 2005 The American Physical Society

    Protective Effect of Nasal Colonisation with ∆cps/piaA and ∆cps/proABCStreptococcus pneumoniae Strains against Recolonisation and Invasive Infection

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    RATIONALE: Nasopharyngeal administration of live virulence-attenuated Streptococcus pneumoniae strains is a potential novel preventative strategy. One target for creating reduced virulence S. pneumoniae strains is the capsule, but loss of the capsule reduces the duration of S. pneumoniae colonisation in mice which could impair protective efficacy against subsequent infection. OBJECTIVES: To assess protective efficacy of nasopharyngeal administration of unencapsulated S. pneumoniae strains in murine infection models. METHODS: Strains containing cps locus deletions combined with the S. pneumoniae virulence factors psaA (reduces colonisation) or proABC (no effect on colonisation) were constructed and their virulence phenotypes and ability to prevent recolonisation or invasive infection assessed using mouse infection models. Serological responses to colonisation were compared between strains using ELISAs, immunoblots and 254 S. pneumoniae protein antigen array. Measurements and Main Results: The ∆cps/piaA and ∆cps/proABC strains were strongly attenuated in virulence in both invasive infection models and had a reduced ability to colonise the nasopharynx. ELISAs, immunoblots and protein arrays showed colonisation with either strain stimulated weaker serological responses than the wild type strain. Mice previously colonised with these strains were protected against septicaemic pneumonia but, unlike mice colonised with the wild type strain, not against S. pneumoniae recolonisation. CONCLUSIONS: Colonisation with the ∆cps/piaA and ∆cps/proABC strains prevented subsequent septicaemia, but in contrast, to published data for encapsulated double mutant strains they did not prevent recolonisation with S. pneumoniae. These data suggest targeting the cps locus is a less effective option for creating live attenuated strains that prevent S. pneumoniae infections

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Fatores associados à interrupção precoce do aleitamento materno: um estudo de coorte de nascimento em dois municípios do Recôncavo da Bahia, Brasil

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    Este estudo objetivou identificar a duração mediana e os fatores associados à interrupção precoce do aleitamento materno. Envolveu uma coorte de nascimento de 531 crianças acompanhadas até os dois anos de idade em dois municípios do Recôncavo da Bahia, Brasil. Utilizaram-se a análise de sobrevivência e o modelo multivariado de Cox. A duração mediana foi de 74,73, 211,25 e 432,63 dias, respectivamente, para o aleitamento materno exclusivo, misto complementado e total. A ausência materna ao pré-natal elevou em 173% (HR = 2,73; IC95%: 1,89-3,93) o risco de diminuir a duração do aleitamento materno exclusivo, em 83% (HR = 1,83; IC95%: 1,06-3,16) o risco da adoção do aleitamento misto complementado e em 38% (HR = 1,38; IC95%: 1,06-1,81) o risco da descontinuidade do aleitamento materno. O trabalho materno fora do domicílio e a área de residência urbana aumentaram o risco para interrupção precoce do aleitamento materno. A ampliação do acesso ao pré-natal e da rede de proteção às mães que trabalham fora do domicilio e àquelas que residem na área urbana poderia aumentar a duração da amamentação no Recôncavo da Bahia.This study aimed to identify the median duration of breastfeeding and associated factors in a cohort of 531 infants in two municipalities in the Recôncavo region, Bahia State, Brazil. Breastfeeding duration was estimated by survival analysis and its associations by the Cox ultivariate model. Median duration of exclusive breastfeeding, mixed breastfeeding with complementary feeding, and total breastfeeding was 74.73, 211.25, and 432.63 days, respectively. Lack of prenatal care increased the risk of shortening exclusive breastfeeding by 173% (HR = 2.73; 95%CI: 1.89-3.93), of adopting mixed breastfeeding with complementary feeding by 83% (HR = 1.83; 95%CI: 1.06-3.16), and of discontinuing breastfeeding entirely by 38% (HR = 1.38; 95%CI: 1.06-1.81). Both maternal employment and residence in an urban area increased the risk of early breastfeeding cessation. Expansion of access to prenatal care and the safety network for employed mothers living in urban areas could increase breastfeeding duration in the target region
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