78 research outputs found
The value of being virtual: User feedback on email and instant messaging reference services
https://deepblue.lib.umich.edu/bitstream/2027.42/154704/1/The_Value_of_Being_Virtual.pd
Effectiveness of single-dose azithromycin to treat latent yaws: a longitudinal comparative cohort study
BACKGROUND: Treatment of latent yaws is a crucial component of
the WHO yaws eradication strategy to prevent relapse and the
resulting transmission to uninfected children. We assessed the
effectiveness of single-dose azithromycin to treat patients with
latent yaws. METHODS: This population-based cohort study
included children (age <20 years) living on Lihir Island,
Papua New Guinea, with high-titre (rapid plasma reagin titre
>/=1:8) latent or active yaws, between April, 2013, and May,
2015. Latent yaws was defined as lack of suspicious skin lesions
or presence of ulcers negative for Treponema pallidum subsp
pertenue on PCR, and active yaws was defined as ulcers positive
for T pertenue on PCR. All children received one oral dose of 30
mg/kg azithromycin. The primary endpoint was serological cure,
defined as a two-dilution decrease in rapid plasma reagin titre
by 24 months after treatment. Treatment of latent yaws was taken
to be non-inferior to that of active yaws if the lower limit of
the two-sided 95% CI for the difference in rates was higher than
or equal to -10%. This study is registered with
ClinicalTrials.gov, number NCT01955252. FINDINGS: Of 311
participants enrolled, 273 (88%; 165 with latent yaws and 108
with active yaws) completed follow-up. The primary endpoint was
achieved in 151 (92%) participants with latent yaws and 101
(94%) with active yaws (risk difference -2.0%, 95% CI -8.3 to
4.3), meeting the prespecified criteria for non-inferiority.
INTERPRETATION: On the basis of decline in serological titre,
oral single-dose azithromycin was effective in participants with
latent yaws. This finding supports the WHO strategy for the
eradication of yaws based on mass administration of the entire
endemic community irrespective of clinical status. FUNDING:
Newcrest Mining Limited and ISDIN laboratories
Velocity-space sensitivity and inversions of synthetic ion cyclotron emission
This paper introduces a new model to find the velocity-space location of energetic ions generating ion cyclotron emission (ICE) in plasmas. ICE is thought to be generated due to inverted gradients in the v⊥ direction of the velocity distribution function or due to anisotropies, i.e., strong gradients in the pitch direction. Here, we invert synthetic ICE spectra generated from first principles PIC-hybrid computations to find the locations of these ICE-generating ions in velocity space in terms of a probability distribution function. To this end, we compute 2D ICE weight functions based on the magnetoacoustic cyclotron instability, which reveals the velocity-space sensitivity of ICE measurements. As an example, we analyze the velocity-space sensitivity of synthetic ICE measurements near the first 15 harmonics for plasma parameters typical for the Large Helical Device. Furthermore, we investigate the applicability of a least-square subset search, Tikhonov regularization, and Lasso regularization to obtain the locations in velocity space of the ions generating the ICE
Integrated Multi-Parameter Exploration Footprints of the Canadian Malartic Disseminated Au, McArthur River-Millennium Unconformity U, and Highland Valley Porphyry Cu Deposits: Preliminary Results from the NSERC-CMIC Mineral Exploration Footprints Research Network
Mineral exploration in Canada is increasingly focused on concealed and deeply buried targets, requiring more effective tools to detect large-scale ore-forming systems and to vector from their most distal margins to their high grade cores. A new generation of ore system models is required to achieve this. The Mineral Exploration Footprints Research Network is a consortium of 70 faculty, research associates, and students from 20 Canadian universities working with 30 mining, mineral exploration, and mining service providers to develop new approaches to ore system modelling based on more effective integration and visualization of multi-parameter geological-structural-mineralogical-lithogeochemical-petrophysical-geophysical exploration data. The Network is developing the next generation ore system models and exploration strategies at three sites based on integrated data visualization using self-consistent 3D Common Earth Models and geostatistical/machine learning technologies. Thus far over 60 footprint components and vectors have been identified at the Canadian Malartic stockwork-disseminated Au deposit, 20–30 at the McArthur-Millennium unconformity U deposits, and over 20 in the Highland Valley porphyry Cu system. For the first time, these are being assembled into comprehensive models that will serve as landmark case studies for data integration and analysis in the today’s challenging exploration environment
Use of Nano Co-Ni-Mn Composite and Aluminum for Removal of Artificial Anionic Dye Congo Red by Combined System
The removal of Congo red (CR) is a critical issue in contemporary textile industry wastewater treatment. The current study introduces a combined electrochemical process of electrocoagulation (EC) and electro-oxidation (EO) to address the elimination of this dye. Moreover, it discusses the formation of a triple composite of (Co), (Mn), and (Ni) oxides by depositing fixed salt ratios (1:1:1) of these oxides in an electrolysis cell at a constant current density of 25 mA/cm2. The deposition ended within 3 hours at room temperature. X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and energy dispersive X-ray (EDX) characterized the structural and surface morphology of the multi-oxide sediment. Marvelously, the deposition has simultaneously occurred on both anodic and cathodic graphite electrodes. These electrodes besides Aluminum (Al) are employed as anodes in the EC-EO system, and the results were optimized by response surface methodology (RSM). The optimum operating conditions were a current density of 6 mA/cm2, pH =7, and NaCl of 0.26 g/L. The results showed that the combined system eliminated more than 99.91% of the Congo red dye with a removal of Chemical Oxygen Demand (COD) of around 97% with 1.64 kWh/kg of dye of the consumed energy. At low current density, the current delivered for the composite anode was more than for the Al anode with the same surface area. On top of this superiority, the EC-EO scenario is a practical hybrid process to remove CR in an environmentally friendly pathway
STRUCTURE AND POLYMORPHISM OF THE HYDROCARBON CHAINS OF LIPIDS : A STUDY OF LECITHIN-WATER PHASES
This work describes the structure of a variety of lecithin-water phases observed below the "melting" temperature of the hydrocarbon chains, with special emphasis on the conformation of the chains. The lecithins studied in this work are the homologous series dioctanoyl to distearoyl, 2-decanoyl-1-stearoyl, and a preparation from hen eggs. The hydrocarbon chains are found to adopt a variety of conformations in additions to type α, the liquid-like organization observed above the melting temperature. Type β : the chains are stiff and parallel, oriented at right angles to the plane of the lamellae and packed with rotational disorder in a two-dimensional hexagonal lattice (a ~ 4.85 Å). Type β' : similar to β, but with the chains tilted with respect to the normal to the lamellae. Type δ : the chains are probably coiled into helices, whose axes are perpendicular to the plane of the polar groups and are packed with rotational disorder in a two-dimensional square lattice (a ~ 4.80 Å). α is the predominant conformation, common to most lipids in the presence of water and at sufficiently high temperature, and the one more relevant to membranes ; δ is observed at lower temperatures in lipids whose chains are heterogeneous and in the presence of very small amounts of water ; β' is found in synthetic lecithins with identical chains, in the presence of variable amounts of water ; δ is observed in dry lecithins. A highly ordered crystalline phase, yet displaying rotational disorder of the chains, is observed in almost dry lecithins. Most of the phases are lamellar, and contain one lipid bilayer per repeat unit. Two phases display two-dimensional lattices: Pδ, formed by ribbon-like elements with the chains in the δ conformation ; Pβ', formed by lamellae of type β' distorted by periodic ripples. The results emphasize the clear-cut difference between the liquid-like and the other types of partly ordered conformations, as well as the correlations which exist between the chemical composition and the structure of the lipids below the melting temperature of the chains
- …