39 research outputs found

    Constraints on the Nucleon Strange Form Factors at Q^2 ~ 0.1 GeV^2

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    We report the most precise measurement to date of a parity-violating asymmetry in elastic electron-proton scattering. The measurement was carried out with a beam energy of 3.03 GeV and a scattering angle =6 degrees, with the result A_PV = -1.14 +/- 0.24 (stat) +/- 0.06 (syst) parts per million. From this we extract, at Q^2 = 0.099 GeV^2, the strange form factor combination G_E^s + 0.080 G_M^s = 0.030 +/- 0.025 (stat) +/- 0.006 (syst) +/- 0.012 (FF) where the first two errors are experimental and the last error is due to the uncertainty in the neutron electromagnetic form factor. This result significantly improves current knowledge of G_E^s and G_M^s at Q^2 ~0.1 GeV^2. A consistent picture emerges when several measurements at about the same Q^2 value are combined: G_E^s is consistent with zero while G_M^s prefers positive values though G_E^s=G_M^s=0 is compatible with the data at 95% C.L.Comment: minor wording changes for clarity, updated references, dropped one figure to improve focu

    Prospective individual patient data meta-analysis of two randomized trials on convalescent plasma for COVID-19 outpatients

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    Data on convalescent plasma (CP) treatment in COVID-19 outpatients are scarce. We aimed to assess whether CP administered during the first week of symptoms reduced the disease progression or risk of hospitalization of outpatients. Two multicenter, double-blind randomized trials (NCT04621123, NCT04589949) were merged with data pooling starting when = 50 years and symptomatic for <= 7days were included. The intervention consisted of 200-300mL of CP with a predefined minimum level of antibodies. Primary endpoints were a 5-point disease severity scale and a composite of hospitalization or death by 28 days. Amongst the 797 patients included, 390 received CP and 392 placebo; they had a median age of 58 years, 1 comorbidity, 5 days symptoms and 93% had negative IgG antibody-test. Seventy-four patients were hospitalized, 6 required mechanical ventilation and 3 died. The odds ratio (OR) of CP for improved disease severity scale was 0.936 (credible interval (CI) 0.667-1.311); OR for hospitalization or death was 0.919 (CI 0.592-1.416). CP effect on hospital admission or death was largest in patients with <= 5 days of symptoms (OR 0.658, 95%CI 0.394-1.085). CP did not decrease the time to full symptom resolution

    Magnetic relaxation analysis of dynamic processes in macromolecules in the pico- to microsecond range.

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    A formalism based on the theory of Markov processes and suitable for the analysis of multiple internal motions in macromolecules is presented. Computer calculations of specific motional models for (13)C nuclear magnetic resonance (NMR) relaxation, treated as special cases of the proposed formalism, demonstrate the potential of this approach for discriminating between different motional models on the basis of NMR relaxation data

    Helium ion beam induced growth of hammerhead AFM probes

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    The authors report the direct-write growth of hammerhead atomic force microscope (AFM) probes by He+ beam induced deposition of platinum-carbon. In order to grow a thin nanoneedle on top of a conventional AFM probe, the authors move a focused He+ beam during exposure to a PtC precursor gas. In the final growth stage, a perpendicular movement of the beam results in the required three-dimensional (hammerhead) shape. The diameter of the needle depends on the ion beam dose, beam dwell time, and speed of the beam movement. A nanoneedle radius below 10 nm and a hammerhead smaller than 35 nm have been achieved. This fabrication process is robust and enables precise control over the three-dimensions of the hammerhead AFM probe. Finally, the authors test the capabilities of the fabricated AFM probes for two-dimensional metrology of sidewall angles and line-edge roughness of trenches and shark-fins in silicon

    SJD in beweging: een onderzoek naar de arbeidsmarkt voor sociaal-Juridische dienstverleners.

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    Dit rapport doet verslag van het onderzoek naar de arbeidsmarktpositie van SJD’ers. Anno 2014 staat het werkveld van de SJD’er voor enkele grote wijzigingen. De belangrijkste daarvan zijn de decentralisaties in het sociaal domein, waarbij verschillende taken op landelijk niveau worden overgeheveld naar de gemeenten. Het onderzoek biedt een basis om de ontwikkelingen in het werkveld van de SJD’er te volgen
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