Simulation of the CTF drive beam line and comparison with the experiment

The tracking of particles in accelerating structures is presented for cases where the effects of the wake-fields are high. This is particularly the case when the structures are used with high current and relatively low energy as in the drive beam of the Compact Linear Collider Test Facility (CTF 2) with its 3 GHz accelerator and its 30 GHz decelerator. High initial energy spread and transverse wake-fields may impair the beam stability and generate particle loss. The CTF modelling is made with the code PARMELA for the 3 GHz part of the beam line, which includes 3 GHz accelerating sections and a magnetic bunch compressor. For the part containing the 30 GHz power-extracting structures, simulations are done with WAKE, a new algorithm dealing with the effects of the wake-field modes 0 and 1, as well as of the group velocity. Beam transmission through the overall beam line is studied, and results are compared with measurements made on the CTF beam

Dissipation Rate of Turbulent Kinetic Energy in Diel Vertical Migrations: Comparison of ANSYS Fluent Model to Measurements

Recent studies suggest that diel vertical migrations of zooplankton may have an impact on ocean mixing, though details are not completely clear. A strong sound scattering layer of zooplankton undergoing diel vertical migrations was observed in Saanich Inlet, British Colombia, Canada by Kunze et al. (2006). In this study, a shipboard 200- kHz echosounder was used to track vertical motion of the sound scattering layer, and microstructure profiles were collected to observe turbulence. An increase of dissipation rate of turbulent kinetic energy by four to five orders of magnitude was measured during diel vertical migrations of zooplankton in one case (but not observed during other cases). A strong sound scattering layer undergoing diel vertical migration was also observed in the Straits of Florida via a bottom mounted acoustic Doppler current profiler at 244 m isobath. A 3-D non-hydrostatic computational fluid dynamics model with Lagrangian particle injections (a proxy for migrating zooplankton) via a discrete phase model was used to simulate the effect of diel vertical migrations on the turbulence for both Saanich Inlet and the Straits of Florida. The model was initialized with idealized (but based on observation) density and velocity profiles. Particles, with buoyancy adjusted to serve as a proxy for vertically swimming zooplankton, were injected to simulate diel vertical migration cycles. Results of models run with extreme concentrations of particles showed an increase in dissipation rate of turbulent kinetic energy of approximately five orders of magnitude over background turbulence during migration of particles in both Saanich Inlet and the Straits of Florida cases (though direct relation of the turbulence produced by buoyant particles and swimming organisms isn’t straightforward). This increase was quantitatively consistent, with turbulence measurements by Kunze et al. (2006). When 10 times fewer particles were injected into the model, the effect on dissipation rate of turbulent kinetic energy was an order of magnitude smaller than that from the extreme concentration. At a concentration of particles 100 times smaller than the extreme concentration, there was no longer an observable effect. In the Straits of Florida, direct turbulence measurements were not available to make a quantitative comparison. However, a small, but statistically significant decrease in northward current velocity profiles during migration times were observed after averaging these profiles over 11 months. A small decrease of current velocity connected to the vertical migrations of particles was reproduced in the Straits of Florida model case. The deviations in the velocity profiles can be explained by the increase in turbulent mixing during vertical migration periods

Creating an Interactive Guide to Support Health Disparities Competency

Authors share their educational resource developed for the health sciences, that guides users in awareness of health disparities, vulnerable populations, and social determinants of health, directing them to specific guidance and resources available through the library

PHIL photoinjector test line

LAL is now equiped with its own platform for photoinjectors tests and Research and Developement, named PHIL (PHotoInjectors at LAL). This facility has two main purposes: push the limits of the photoinjectors performances working on both the design and the associated technology and provide a low energy (MeV) short pulses (ps) electron beam for the interested users. Another very important goal of this machine will be to provide an opportunity to form accelerator physics students, working in a high technology environment. To achieve this goal a test line was realised equipped with an RF source, magnets and beam diagnostics. In this article we will desrcibe the PHIL beamline and its characteristics together with the description of the first two photoinjector realised in LAL and tested: the ALPHAX and the PHIN RF Guns

Role of orexin A signaling in dietary palmitic acid-activated microglial cells

AbstractExcess dietary saturated fatty acids such as palmitic acid (PA) induce peripheral and hypothalamic inflammation. Hypothalamic inflammation, mediated in part by microglial activation, contributes to metabolic dysregulation. In rodents, high fat diet-induced microglial activation results in nuclear translocation of nuclear factor-kappa B (NFκB), and increased central pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). The hypothalamic neuropeptide orexin A (OXA, hypocretin 1) is neuroprotective in brain. In cortex, OXA can also reduce inflammation and neurodegeneration through a microglial-mediated pathway. Whether hypothalamic orexin neuroprotection mechanisms depend upon microglia is unknown. To address this issue, we evaluated effects of OXA and PA on inflammatory response in immortalized murine microglial and hypothalamic neuronal cell lines. We demonstrate for the first time in microglial cells that exposure to PA increases gene expression of orexin-1 receptor but not orexin-2 receptor. Pro-inflammatory markers IL-6, TNF-α, and inducible nitric oxide synthase in microglial cells are increased following PA exposure, but are reduced by pretreatment with OXA. The anti-inflammatory marker arginase-1 is increased by OXA. Finally, we show hypothalamic neurons exposed to conditioned media from PA-challenged microglia have increased cell survival only when microglia were pretreated with OXA. These data support the concept that OXA may act as an immunomodulatory regulator of microglia, reducing pro-inflammatory cytokines and increasing anti-inflammatory factors to promote a favorable neuronal microenvironment

A menthol-enhanced “cooling” energy gel does not influence laboratory time trial performance in trained runners

l-menthol (menthol) is an organic compound derived from peppermint which imparts a refreshing mint flavor and aroma to oral hygiene products, chewing gum, and topical analgesics. Menthol has been identified as a non-thermal sensory cooling strategy for athletes when ingested or mouth-rinsed during exercise in hot environments. Therefore, sports nutrition products delivering a controlled concentration of menthol could be beneficial for athletes exercising in the heat. We sought to test the performance and perceptual outcomes of a novel menthol energy gel during treadmill running in the heat (33 °C, 49% RH). Fourteen trained runners (mean ± SD; age: 31 ± 6 years, VO2max: 56.5 ± 10.1 mL·kg−1·min−1, BMI: 23.2 ± 2.4 kg/m2; six female) participated in a randomized, crossover, double-blind, and placebo-controlled study. A menthol-enhanced energy gel (0.5% concentration; MEN) or flavor-matched placebo (PLA) was ingested 5 min before and again at 20 and 40 min of a 40 min treadmill exercise preload at 60% VO2max, followed by a 20 min self-paced time trial. The total distance, vertical distance, perceptual measures (thermal comfort, thermal sensation, rating of perceived exertion, and affect), and cognitive performance via computerized neurocognitive assessment were measured. No difference between 20 min self-paced time trial total distance (MEN: 4.22 ± 0.54 km, PLA: 4.22 ± 0.55 km, p = 0.867), vertical distance (MEN: 49.2 ± 24.6 m, PLA: 44.4 ± 11.4 m, p = 0.516), or any perceptual measures was observed (all p > 0.05). Cognitive performance was not different between the trials (all p > 0.05). These results suggest that a menthol energy gel is not superior to a non-menthol gel in terms of performance or perception during treadmill running in the heat. More research is needed to confirm whether these findings translate to ecologically valid settings, including outdoor exercise in ambient heat and during competition

Low Energy Beam Measurements Using PHIL Accelerator at LAL, Comparison with PARMELA Simulations

http://accelconf.web.cern.ch/AccelConf/PAC2011/papers/wep210.pdfInternational audiencePHIL ("PHo­to-In­jec­tor at LAL") is a new elec­tron beam ac­cel­er­a­tor at LAL. This ac­cel­er­a­tor is ded­i­cat­ed to test and char­ac­ter­ize elec­tron RF-guns and to de­liv­er elec­tron beam to users. This ma­chine has been de­signed to pro­duce and char­ac­terise low en­er­gy (E<10 MeV), small emit­tance (e<10 p.​mm.​mrad), high bril­liance elec­trons bunch at low rep­e­ti­tion fre­quen­cy (n<10Hz). The first beam has been ob­tained on the 4th of Novem­ber 2009. The cur­rent RF-gun test­ed on PHIL is the Al­phaX gun, a 2.5 cell S-band cav­i­ty de­signed by LAL for the plas­ma ac­cel­er­a­tor stud­ies per­formed at the Strath­clyde uni­ver­si­ty. This paper will pre­sent the first Al­phaX RF-gun char­ac­ter­i­za­tions per­formed at LAL on PHIL ac­cel­er­a­tor, and will show com­par­isons be­tween mea­sure­ments and PARMELA sim­u­la­tions

Erratum to: Providing Patients with Implantable Cardiac Device Data through a Personal Health Record: A Qualitative Study

Erratum to: Providing Patients with Implantable Cardiac Device Data through a Personal Health Record: A Qualitative Study. [Appl Clin Inform. 2017

Commissioning of the ALTO 50 MeV electron linac

online : http://accelconf.web.cern.ch/AccelConf/e06/PAPERS/MOPLS113.pdfThe ALTO 50 MeV electron linac is dedicated to the production of neutron-rich radioactive nuclei using the photo-fission process and the optimisation of the targetion source system for SPIRAL 2 and EURISOL projects. The accelerator consists of a 3 MeV injector (old test station of LAL, Laboratoire de l'Accélérateur Linéaire d'Orsay), LIL (Linac Injector of LEP) accelerating structure, RF power plant, beam line, control system and diagnostics. Specified and measured beam parameters will be compared to show the performances of the photofission process and eventually other applications