1,066 research outputs found

    PRUSSIC II -- ALMA imaging of dense-gas tracers in SDP.81: Evidence for low mechanical heating and a sub-solar metallicity in a z=3.04 dusty galaxy

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    We present deep ALMA Band 3 observations of the HCN, HCO+, and HNC (4-3) emission in SDP.81, a well-studied z = 3.042 strongly lensed galaxy. These lines trace the high-density gas, which remains almost entirely unexplored in z≄\geq1 galaxies. Additionally, these dense-gas tracers are potentially powerful diagnostics of the mechanical heating of the interstellar medium. While the HCN(4-3) and HNC(4-3) lines are not detected, the HCO+(4-3) emission is clearly detected and resolved. This is the third detection of this line in a high-redshift star-forming galaxy. We find an unusually high HCO+/HCN intensity ratio of ≄\geq2.2. Based on the photodissociation region modelling, the most likely explanation for the elevated HCO+/HCN ratio is that SDP.81 has low mechanical heating - less than 10% of the total energy budget - and a sub-solar metallicity, Z=0.5 Z⊙_\odot. While such conditions might not be representative of the general population of high-redshift dusty galaxies, lower-than-solar metallicity might have a significant impact on gas masses inferred from CO observations. In addition, we report the detection of CO(0-1) absorption from the foreground lensing galaxy and CO(1-0) emission from a massive companion to the lensing galaxy, approximately 50 kpc to the southeast.Comment: A&A accepted, in press. 10 pages, 10 figure

    Waves and Magnetism in the Solar Atmosphere (WAMIS)

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    Comprehensive measurements of magnetic fields in the solar corona have a long history as an important scientific goal. Besides being crucial to understanding coronal structures and the Sun's generation of space weather, direct measurements of their strength and direction are also crucial steps in understanding observed wave motions. In this regard, the remote sensing instrumentation used to make coronal magnetic field measurements is well suited to measuring the Doppler signature of waves in the solar structures. In this paper, we describe the design and scientific values of the Waves and Magnetism in the Solar Atmosphere (WAMIS) investigation. WAMIS, taking advantage of greatly improved infrared filters and detectors, forward models, advanced diagnostic tools and inversion codes, is a long-duration high-altitude balloon payload designed to obtain a breakthrough in the measurement of coronal magnetic fields and in advancing the understanding of the interaction of these fields with space plasmas. It consists of a 20 cm aperture coronagraph with a visible-IR spectro-polarimeter focal plane assembly. The balloon altitude would provide minimum sky background and atmospheric scattering at the wavelengths in which these observations are made. It would also enable continuous measurements of the strength and direction of coronal magnetic fields without interruptions from the day–night cycle and weather. These measurements will be made over a large field-of-view allowing one to distinguish the magnetic signatures of different coronal structures, and at the spatial and temporal resolutions required to address outstanding problems in coronal physics. Additionally, WAMIS could obtain near simultaneous observations of the electron scattered K-corona for context and to obtain the electron density. These comprehensive observations are not provided by any current single ground-based or space observatory. The fundamental advancements achieved by the near-space observations of WAMIS on coronal field would point the way for future ground based and orbital instrumentation

    Odanacatib for the treatment of postmenopausal osteoporosis: Development history and design and participant characteristics of LoFT, the Long-term odanacatib Fracture Trial

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    Summary: Odanacatib is a cathepsin K inhibitor investigated for the treatment of postmenopausal osteoporosis. Phase 2 data indicate that 50 mg once weekly inhibits bone resorption and increases bone mineral density, with only a transient decrease in bone formation. We describe the background, design and participant characteristics for the phase 3 registration trial. Introduction: Odanacatib (ODN) is a selective cathepsin K inhibitor being evaluated for the treatment of osteoporosis. In a phase 2 trial, ODN 50 mg once weekly reduced bone resorption while preserving bone formation and progressively increased BMD over 5 years. We describe the phase III Long-Term ODN Fracture Trial (LOFT), an event-driven, randomized, blinded placebo-controlled trial, with preplanned interim analyses to permit early termination if significant fracture risk reduction was demonstrated. An extension was planned, with participants remaining on their randomized treatment for up to 5 years, then transitioning to open-label ODN. Methods: The three primary outcomes were radiologically determined vertebral, hip, and clinical non-vertebral fractures. Secondary end points included clinical vertebral fractures, BMD, bone turnover markers, and safety and tolerability, including bone histology. Participants were women, 65 years or older, with a BMD T-score ≀−2.5 at the total hip (TH) or femoral neck (FN) or with a prior radiographic vertebral fracture and a T-score ≀−1.5 at the TH or FN. They were randomized to ODN or placebo tablets. All received weekly vitamin D3 (5600 international units (IU)) and daily calcium supplements as needed to ensure a daily intake of approximately 1200 mg. Results: Altogether, 16,713 participants were randomized at 387 centers. After a planned interim analysis, an independent data monitoring committee recommended that the study be stopped early due to robust efficacy and a favorable benefit/risk profile. Following the base study closeout, 8256 participants entered the study extension. Conclusions: This report details the background and study design of this fracture end point trial and describes the baseline characteristics of its participants

    Sensorineural hearing loss in Lassa fever: two case reports

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    <p>Abstract</p> <p>Introduction</p> <p>Lassa fever is an acute arena viral haemorrhagic fever with varied neurological sequelae. Sensorineural hearing loss is one of the rare complications which occur usually during the convalescent stage of the infection.</p> <p>Case presentation</p> <p>The cases of two female patients aged 19 and 43 years old, respectively, with clinical features suggestive of Lassa fever and confirmed by immunoserological/Lassa-virus-specific reverse transcriptase polymerase chain reaction are presented. Both patients developed severe sensorineural hearing loss at acute phases of the infections.</p> <p>Conclusion</p> <p>Sensorineural hearing loss from Lassa fever infections can occur in both acute and convalescent stages and is probably induced by an immune response.</p

    The study of vancomycin use and its adverse reactions associated to patients of a brazilian university hospital

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    <p>Abstract</p> <p>Background</p> <p>Vancomycin is an antibiotic of growing importance in the treatment of hospital infections, with particular emphasis on its value in the fight against methicillin-resistant <it>Staphylococcus aureus</it>. However its usage profile must be evaluated to assure maximum benefit and minimum risk.</p> <p>Findings</p> <p>A cross-sectional retrospective study was carried out among inpatients that received vancomycin in a Brazilian quaternary hospital. The occurrence of adverse reactions reported was evaluated in medical records relating to patients taking vancomycin during a one year period. Males comprised 52% (95% CI: 41.7-60.2%) of the sample population, with a mean age of 50.6 (95% CI: 47.2-54.0) years and mean treatment period of 9.7 (95% CI: 8.0-11.5) Days. It was verified that nephrotoxicity occurred in 18.4% (95% CI: 11.3-27.5) of patients, Red man syndrome occurred in 2% (95% CI 0.2-7.2), while the occurrence of thrombocytopenia was 7.1% (95% CI: 2.9-14.2).</p> <p>Conclusions</p> <p>It may be noted that even after 50 years of use, adverse reactions associated with vancomycin continue with high frequency, presenting a public health problem, especially considering its current use in cases of multidrug resistant infections. In this context, we emphasize the importance of intensive pharmacovigilance in hospital as a surveillance tool after drug approval by the sanitary authority.</p

    Modulation by steroid hormones of a "sexy" acoustic signal in an Oscine species, the Common Canary Serinus canaria

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    The respective influence of testosterone and estradiol on the structure of the Common Canary Serinus canaria song was studied by experimentally controlling blood levels of steroid hormones in males and analyzing the consequent effects on acoustic parameters. A detailed acoustic analysis of the songs produced before and after hormonal manipulation revealed that testosterone and estradiol seem to control distinct song parameters independently. The presence of receptors for testosterone and estradiol in the brain neural pathway controlling song production strongly suggests that the observed effects are mediated by a steroid action at the neuronal level.<br>A influĂȘncia da testosterona e do estradiol, respectivamente, na estrutura do canto do CanĂĄrio-do-reino Serinus canaria foi estudada analisando o efeito da manipulação dos nĂ­veis sanguĂ­neos de hormĂŽnios esterĂłides em machos nos parĂąmetros acĂșsticos do canto. Uma analise detalhada dos cantos produzidos antes e depois da manipulação hormonal revelou que testosterona e estradiol parecem controlar independentemente parĂąmetros acĂșsticos distintos. A presença de receptores para esses hormĂŽnios no circuito neuronal para controle da produção do canto sugere fortemente que os efeitos observados sĂŁo mediados pela ação de esterĂłides a nivel neuronal

    Opinion dynamics: models, extensions and external effects

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    Recently, social phenomena have received a lot of attention not only from social scientists, but also from physicists, mathematicians and computer scientists, in the emerging interdisciplinary field of complex system science. Opinion dynamics is one of the processes studied, since opinions are the drivers of human behaviour, and play a crucial role in many global challenges that our complex world and societies are facing: global financial crises, global pandemics, growth of cities, urbanisation and migration patterns, and last but not least important, climate change and environmental sustainability and protection. Opinion formation is a complex process affected by the interplay of different elements, including the individual predisposition, the influence of positive and negative peer interaction (social networks playing a crucial role in this respect), the information each individual is exposed to, and many others. Several models inspired from those in use in physics have been developed to encompass many of these elements, and to allow for the identification of the mechanisms involved in the opinion formation process and the understanding of their role, with the practical aim of simulating opinion formation and spreading under various conditions. These modelling schemes range from binary simple models such as the voter model, to multi-dimensional continuous approaches. Here, we provide a review of recent methods, focusing on models employing both peer interaction and external information, and emphasising the role that less studied mechanisms, such as disagreement, has in driving the opinion dynamics. [...]Comment: 42 pages, 6 figure
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