1,473 research outputs found

    An update of the on-sky performance of the Layer-Oriented wave-front sensor for MAD

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    The Multi-conjugate Adaptive optics Demonstrator, MAD, successfully demonstrated on sky the MCAO technique both in Layer Oriented and Star Oriented modes. As results of the Guaranteed Time Observations in Layer Oriented mode quality astronomy papers have been published. In this paper we concentrate on the instrumentation issues and technical aspects which stay behind this success.Comment: 12 pages, 10 figures, Proceedings of the SPIE conference "Adaptive Optics Systems II", 27 June 2010, San Diego, California, US

    Higgs Boson Production in Association with a Photon in Vector Boson Fusion at the LHC

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    Higgs boson production in association with two forward jets and a central photon at the CERN Large Hadron Collider is analyzed, for the Higgs boson decaying into a b bbar pair in the m_H <= 140 GeV mass region. We study both irreducible and main reducible backgrounds at parton level. Compared to the Higgs production via vector-boson fusion, the request of a further photon at moderate rapidities dramatically enhances the signal/background ratio. Inclusive cross sections for p_T^\gamma >= 20 GeV can reach a few tens of fb's. After a suitable choice of kinematical cuts, the cross-section ratio for signal and irreducible-background can be enhanced up to >= ~1/10, with a signal cross section of the order of a few fb's, for m_H ~ 120 GeV. The request of a central photon radiation also enhances the relative signal sensitivity to the WWH coupling with respect to the ZZH coupling. Hence, a determination of the cross section for the associated production of a Higgs boson decaying into a b bbar pair plus a central photon in vector-boson fusion could help in constraining the b bbar H coupling, and the WWH coupling as well. A preliminary study of QCD showering effects points to a further significant improvement of the signal detectability over the background.Comment: 30 pages, 8 figures, 8 tables; minor corrections to the text; version appeared in Nuclear Physics

    Erwinia oleae sp. nov., isolated from olive knots caused by Pseudomonas savastanoi pv. savastanoi

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    Three endophytic bacterial isolates were obtained in Italy from olive knots caused by Pseudomonas savastanoi pv. savastanoi. Phenotypic tests in combination with 16S rRNA gene sequence analysis indicated a phylogenetic position of these isolates in the genus Erwinia or Pantoea, and revealed two other strains with highly similar 16S rRNA gene sequences (> 99 %), CECT 5262 and CECT 5264, obtained in Spain from olive knots. Rep-PCR DNA fingerprinting of the five strains from olive knots with BOX, ERIC and REP primers revealed three groups of profiles that were highly similar to each other. Multilocus sequence analysis (MLSA) based on concatenated partial atpD, gyrB, infB and rpoB gene sequences, indicated that the strains constitute a single novel species in the genus Erwinia. The strains showed general phenotypic characteristic of Erwinia, and whole genome DNA-DNA hybridization data confirmed they represent a single novel Erwinia species. The strains showed a DNA G+C base composition ranging from 54.7 to 54.9 mol%. They could be discriminated from the phylogenetically related Erwinia species by their ability to utilise potassium gluconate, L-rhamnose and D-arabitol, but not glycerol, inositol and D-sorbitol. The name Erwinia oleae (type strain DAPP-PG 531T = LMG 25322T = DSM 23398T) is proposed for this new taxon

    The space density of z>4 blazars

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    High redshift blazars are an important class of Active Galactic Nuclei (AGN) that can provide an independent estimate of the supermassive black-hole mass function in high redshift radio-loud AGN without the bias due to absorption along the line-of-sight. Using the Cosmic Lens All Sky Survey (CLASS) we built a complete radio flux-limited sample of high redshift (z>4) blazars suitable for statistical studies. By combining dedicated optical observations and the SDSS spectroscopic database, we obtained a sample of 26 blazar candidates with a spectroscopic redshift above 4. On the basis of their radio spectrum we distinguish between blazars and QSO with a Gigahertz Peaked Spectrum (GPS) like spectrum. Out of the 18 confirmed blazars 14 constitute a completely identified, flux-limited sample down to a magnitude of 21 (AB). Using this complete sample we derive a space density of blazars with 4<z<5.5 of rho=0.13 (+0.05,-0.03) Gpc^-3. This is the first actual estimate of the blazar space density in this range of redshift. This value is in good agreement with the extrapolation of the luminosity function and cosmological evolution based on a sample of flat-spectrum radio quasars selected at lower redshifts and it is consistent with a cosmological evolution peaking at z\sim2 similar to radio-quiet QSO. We do not confirm, instead, the presence of a peak at z~4 in the space density evolution, recently suggested using an X-ray selected sample of blazars. It is possible that this extreme peak of the evolution is present only among the most luminous blazars.Comment: 14 pages, accepted for publication on MNRAS (https://doi.org/10.1093/mnras/sty3526

    Assessing knowledge on fibromyalgia among internet users

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    OBJECTIVE: To assess knowledge on fibromyalgia in a sample of patients, their families, and professionals interested on the theme from some Brazilian states. METHODS: Analysis of the results of an electronic fibromyalgia knowledge questionnaire completed by 362 adults who had access to the the support group for fibromyalgia site (www.unifesp.br/grupos/fibromialgia). The answers were grouped according to age, sex, years of schooling, and type of interest in the condition. RESULTS: 92% of the responders were women and 62% had higher educational level. The worst results were observed in the joint protection and energy conservation domain, followed by the medication in fibromyalgia domain. The best results were recorded in the exercises in fibromyalgia domain. The answers differed significantly between sexes, and women achieved a higher percentage of correct answers. The female sex accounted for a statistically superior result in five statistical analyses (four questions and one domain). CONCLUSIONS: The study suggests the need for a strategic planning for an educational approach to fibromyalgia in BrazilOBJETIVO: Analisar o nível de conhecimento sobre fibromialgia em uma amostra incluindo pacientes, familiares e profissionais de vários estados do Brasil. MÉTODOS: Análise dos resultados de 362 adultos que acessaram o site do Grupo de Apoio à Fibromialgia (www.unifesp.br/grupos/fibromialgia) e responderam a um questionário eletrônico de conhecimento sobre a síndrome. As respostas foram avaliadas em relação a idade, sexo, nível de escolaridade e tipo de interesse no Grupo. RESULTADOS: 92% eram mulheres e 62% haviam completado o ensino superior. O pior resultado foi no domínio proteção articular e conservação de energia, seguido pelo domínio conhecimento sobre medicação. O melhor resultado ocorreu no domínio exercícios para fibromialgia. Houve diferença significativa entre os gêneros, sendo as mulheres responsáveis por um porcentual maior de acertos. O gênero feminino foi responsável por um resultado estatisticamente superior em cinco análises estatísticas (quatro perguntas e um domínio). CONCLUSÕES: O estudo sugere a necessidade de um planejamento estratégico para ações educativas sobre fibromialgia no BrasilUNIFESP Centro Cochrane do BrasilUniversidade Federal do ABCUNIFESPCentro CochraneUNIFESP, Centro Cochrane do BrasilUNIFESPSciEL

    Andic soils and catastrophic mudflows in Italy: morphological and hydropedological evidences

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    In Italy rapid landslides are the most frequently occurring natural disasters and, after earthquakes, cause the highest number of victims. In this contribution we attempt to prove that there exist a tight connection between the presence of a specific soil type, namely andic soils, and the occurrence of the main catastrophic mudflows and debris flows occurred in Italy in the last decades. The study was performed by means of an integrated pedological and hydrological analysis on the detachment crowns of some of the most important catastrophic mudflows and debris flows occurred in Italy in the last decades and involving/evolving surface soils. The results at both regional (Campania) and National (Italy) scale clearly show that despite the large variability of the environmental settings of the studied sites there are indeed some striking homogeneous soil features in the detachment crowns including (i) soil morphology, (ii) andic features ranging from high to moderate, (iii) high water retention throughout a large range of pressure heads. Results seem to reveal clear cause-effect evidences between andic soils and the investigated catastrophic mudflows/debrisflows; this must be related to the unique physical properties of these soils inducing high landslide vulnerability

    Spin-orbit torques for current parallel and perpendicular to a domain wall

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    We report field- and current-induced domain wall (DW) depinning experiments in Ta/Co20Fe60B20/MgO nanowires through a Hall cross geometry. While purely field-induced depinning shows no angular dependence on in-plane fields, the effect of the current depends crucially on the internal DW structure, which we manipulate by an external magnetic in-plane field. We show for the first time depinning measurements for a current sent parallel to the DW and compare its depinning efficiency with the conventional case of current flowing perpendicularly to the DW. We find that the maximum efficiency is similar for both current directions within the error bars, which is in line with a dominating damping-like spin-orbit torque (SOT) and indicates that no large additional torques arise for currents parallel to the DW. Finally, we find a varying dependence of the maximum depinning efficiency angle for different DWs and pinning levels. This emphasizes the importance of our full angular scans compared to previously used measurements for just two field directions (parallel and perpendicular to the DW) and shows the sensitivity of the spin-orbit torque to the precise DW structure and pinning sites.Comment: 11 pages, 3 figure

    Exploring the Low Voltage Behavior of V2O5Aerogel as Intercalation Host for Sodium Ion Battery

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    Boosted by costs benefits, the development of room temperature Na-ion batteries is strongly desired for stationary applications. In this study we explore the possible use of V2O5 aerogel as anode material for sodium ion batteries. The aerogel is able to reversibly insert more than 3 Eq. of sodium in the voltage range 0.1 V–4 V vs. Na/Na+ demonstrating to possess additional capacity when cycled to lower voltage. The anode delivers about 200 mAh g−1 in the voltage range 0.01 V–1.5 V vs. Na/Na+. The preliminary characterization of a full Na-ion cell made coupling the V2O5 aerogel anode with carbon-coated Na3V2(PO4)3 cathode is also reported. The cell, showing an average voltage of 2.5 V, performed 200 cycles with good efficiency and a maximum specific capacity of 113 mAh per gram of anode material

    Health workforce development: a needs assessment study in French speaking African countries

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    In 2006, WHO alerted the world to a global health workforce crisis, demonstrated through critical shortages of health workers, primarily in Sub-Saharan Africa (WHO in World Health Report, 2006). The objective of our study was to assess, in a participative way, the educational needs for public health and health workforce development among potential trainees and training institutions in nine French-speaking African countries. A needs assessment was conducted in the target countries according to four approaches: (1) Review at national level of health challenges. (2) Semi-directed interviews with heads of relevant training institutions. (3) Focus group discussions with key-informants. (4) A questionnaire-based study targeting health professionals identified as potential trainees. A needs assessment showed important public health challenges in the field of health workforce development among the target countries (e.g. unequal HRH distribution in the country, ageing of HRH, lack of adequate training). It also showed a demand for education and training institutions that are able to offer a training programme in health workforce development, and identified training objectives and core competencies useful to potential employers and future trainees (e.g. leadership, planning/evaluation, management, research skill). In combining various approaches our study was able to show a general demand for health managers who are able to plan, develop and manage a nation's health workforce. It also identified specific competencies that should be developed through an education and training program in public health with a focus on health workforce developmen
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