1,182 research outputs found
A propos des formalités sanitaires officielles concernant les transports internationaux de chevaux
Lucas J. A propos des formalités sanitaires officielles, concernant les transports internationaux de chevaux. In: Bulletin de l'Académie Vétérinaire de France tome 126 n°6, 1973. pp. 273-275
Digital Literacy, Fake News and Education
The role of digital literacy in strengthening citizensâ resilience to misinformation and âfake newsâ has been the subject of research projects and networking and academic and policy discourses in recent years, given prominence by an escalation of the perceived crisis following election and referendum results in the US and UK respectively. This special issue sets out to take forward critical dialogue in the field of media and digital literacy education by publishing rigorous research on the subject. The research disseminated in this collection speaks to the political and economic contexts for âfake newsâ, the complex issue of trust and the risks of educational solutionism; questions of definition and policy implementation; teaching about specific subgenres such as YouTube and clickbait; international comparisons of pedagogic approaches and challenges for teachers in this changing ecosystem
All-Optical Broadband Excitation of the Motional State of Trapped Ions
We have developed a novel all-optical broadband scheme for exciting,
amplifying and measuring the secular motion of ions in a radio frequency trap.
Oscillation induced by optical excitation has been coherently amplified to
precisely control and measure the ion's secular motion. Requiring only laser
line-of-sight, we have shown that the ion's oscillation amplitude can be
precisely controlled. Our excitation scheme can generate coherent motion which
is robust against variations in the secular frequency. Therefore, our scheme is
ideal to excite the desired level of oscillatory motion under conditions where
the secular frequency is evolving in time. Measuring the oscillation amplitude
through Doppler velocimetry, we have characterized the experimental parameters
and compared them with a molecular dynamics simulation which provides a
complete description of the system.Comment: 8 pages, 10 figure
Supersymmetry without Supersymmetry
We present four-dimensional M-theory vacua with N>0 supersymmetry which, from
the perspective of perturbative Type IIA string theory, have N=0. Such vacua
can appear when the compactifying 7-manifold is a U(1) fibration. The missing
superpartners are Dirichlet 0-branes. Someone unable to detect Ramond-Ramond
charge would thus conclude that these worlds have no unbroken supersymmetry. In
particular, the gravitinos (and also some of the gauge bosons) are 0-branes not
seen in perturbation theory but which curiously remain massless however weak
the string coupling.Comment: Latex, 16 pages. Minor revisions and reference adde
Aerosol direct radiative effects of a transatlantic biomass burning plume over Granada, Spain
This work presents the assessment of the aerosol direct radiative effects for a special episode of transatlantic transport of a biomass burning plume, performed over Granada, south-eastern Iberian Peninsula, on 20th August 2007. The knowledge of aerosol radiative impact requires an accurate determination of their optical and microphysical properties, which are obtained here using ground-based remote sensing instrumentation by means of a combination of lidar and sun-photometer. Our data highlight the presence of a multilayered structure with a well-defined planetary boundary layer and biomass-particles in elevated layers, extending up to 9 km asl, at the south-eastern part of the Iberian Peninsula.
The aerosol direct shortwave radiative effects, evaluated from simulations with SBDART code, show that the biomass burning plume increases the heating rate up to 0.5 K/day in spite of the small contribution of these particles to the total aerosol optical depth (10-20%). In addition, our results indicate that the biomass burning plume strengths the negative radiative forcing about -5 down to -8 W/m2 at the surface, between noon and evening. At the TOA, radiative forcing appeared slightly positive but very close to zero at noon, and negative in the evening with a decrease of 1.5 W/m2 caused by the presence of the biomass burning plume.Postprint (published version
The distribution of transit durations for Kepler planet candidates and implications for their orbital eccentricities
âIn these times, during the rise in the popularity of institutional repositories, the Society does not forbid authors from depositing their work in such repositories. However, the AAS regards the deposit of scholarly work in such repositories to be a decision of the individual scholar, as long as the individual's actions respect the diligence of the journals and their reviewers.â Original article can be found at : http://iopscience.iop.org/ Copyright American Astronomical SocietyDoppler planet searches have discovered that giant planets follow orbits with a wide range of orbital eccentricities, revolutionizing theories of planet formation. The discovery of hundreds of exoplanet candidates by NASA's Kepler mission enables astronomers to characterize the eccentricity distribution of small exoplanets. Measuring the eccentricity of individual planets is only practical in favorable cases that are amenable to complementary techniques (e.g., radial velocities, transit timing variations, occultation photometry). Yet even in the absence of individual eccentricities, it is possible to study the distribution of eccentricities based on the distribution of transit durations (relative to the maximum transit duration for a circular orbit). We analyze the transit duration distribution of Kepler planet candidates. We find that for host stars with T > 5100 K we cannot invert this to infer the eccentricity distribution at this time due to uncertainties and possible systematics in the host star densities. With this limitation in mind, we compare the observed transit duration distribution with models to rule out extreme distributions. If we assume a Rayleigh eccentricity distribution for Kepler planet candidates, then we find best fits with a mean eccentricity of 0.1-0.25 for host stars with T †5100 K. We compare the transit duration distribution for different subsets of Kepler planet candidates and discuss tentative trends with planetary radius and multiplicity. High-precision spectroscopic follow-up observations for a large sample of host stars will be required to confirm which trends are real and which are the results of systematic errors in stellar radii. Finally, we identify planet candidates that must be eccentric or have a significantly underestimated stellar radius.Peer reviewedFinal Accepted Versio
Changes in serum neurofilament light chain levels following narrowband ultraviolet B phototherapy in clinically isolated syndrome
Objective
To determine whether serum neurofilament light chain (sNfL) levels are suppressed in patients with the clinically isolated syndrome (CIS) following narrowband ultraviolet B phototherapy (UVB-PT).
Methods
sNfL levels were measured using a sensitive single-molecule array assay at baseline and up to 12 months in 17 patients with CIS, 10 of whom received UVB-PT, and were compared with healthy control (HC) and early relapsing remitting multiple sclerosis (RRMS) group. sNfL levels were correlated with magnetic resonance imaging total lesion volume (LV) determined using icobrain version 4.4.1 and with clinical outcomes.
Results
Baseline median sNfL levels were significantly higher in the CIS (20.6 pg/mL, interquartile range [IQR] 13.7â161.4) and RRMS groups (36.6 pg/ml [IQR] 16.2â212.2) than in HC (10.7 pg/ml [IQR] 4.9â21.5) (p = .012 and p = .0002, respectively), and were strongly correlated with T2 and T1 LV at 12 months (r = .800; p = .014 and r = .833; p = .008, respectively) in the CIS group. Analysis of changes in sNfL levels over time in the CIS group showed a significant cumulative suppressive effect of UVB-PT in the first 3 months (UVB-PT â10.6% vs non-UVB-PT +58.3%; p = .04) following which the levels in the two groups converged and continued to fall.
Conclusions
Our findings provide the basis for further studies to determine the utility of sNfL levels as a marker of neuro-axonal damage in CIS and early MS and for assessing the efficacy of new therapeutic interventions such as UVB-PT
Experimental study and simulation of mass distribution of the covering layer of soybean seeds coated in a spouted bed
Synthesis, surface active and antimicrobial properties of new alkyl 2,6-dideoxy-L-arabino-hexopyranosides
Synthesis of alkyl 2,6-dideoxy-L-arabino-hexopyranosides was accomplished by the reaction of 1,5-anhydro-2,6-dideoxy-L-arabino-hex-1-enitol with fatty alcohols in dichloromethane, catalyzed by triphenylphosphine hydrobromide. Reaction with octanol and dodecanol gave the corresponding α-glycosides in 50% and 42% yield, the ÎČ-glycosides in 20% and 21% yield and the α-anomer of the Ferrier product in 10% and 9% yield, respectively.Deacetylation of the α-/ÎČ-glycosides with sodium methoxide in methanol afforded the amphiphilic L-arabino-hexopyranosides in 94â99% yield. The surface tension at the airâwater interface of the octyl L-glycosides and of the dodecyl α-L-glycoside aqueous solutions at 35 °C was measured with a du NoĂŒy ring tensiometer and surface properties such as critical micelle concentration (CMC), relative surface excess, molecular area at the interface and Gibbs micellization free energy were evaluated. The stereochemistry of the hexopyranoside ring in unimers and aggregates is correlated to the hydrophobicity and packing efficiency on the airâwater interface. The antibacterial and antifungal activities of the surface-active glycosides were evaluated using the paper disk diffusion method. The dodecyl α-L-arabino-hexopyranoside was quite active over Bacillus cereus and Bacillus subtilis, while low activity was found for this glycoside over Enterococcus faecalis and Listeria monocytogenes. The octyl glycosides tested showed low activity over almost all the above-mentioned bacteria, and also over the fungus Candida albicans. No inhibition of Salmonella enteritidis and of the filamentous fungus Aspergillus niger was detected for any of the compounds tested.info:eu-repo/semantics/publishedVersio
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