The relativistic solar particle event of 2005 January 20: origin of delayed particle acceleration

The highest energies of solar energetic nucleons detected in space or through gamma-ray emission in the solar atmosphere are in the GeV range. Where and how the particles are accelerated is still controversial. We search for observational information on the location and nature of the acceleration region(s) by comparing the timing of relativistic protons detected on Earth and radiative signatures in the solar atmosphere during the particularly well-observed 2005 Jan. 20 event. This investigation focuses on the post-impulsive flare phase, where a second peak was observed in the relativistic proton time profile by neutron monitors. This time profile is compared in detail with UV imaging and radio spectrography over a broad frequency band from the low corona to interplanetary space. It is shown that the late relativistic proton release to interplanetary space was accompanied by a distinct new episode of energy release and electron acceleration in the corona traced by the radio emission and by brightenings of UV kernels. These signatures are interpreted in terms of magnetic restructuring in the corona after the coronal mass ejection passage. We attribute the delayed relativistic proton acceleration to magnetic reconnection and possibly to turbulence in large-scale coronal loops. While Type II radio emission was observed in the high corona, no evidence of a temporal relationship with the relativistic proton acceleration was found

A constrained sports scheduling problem

AbstractA real case of sports scheduling problem is presented. A calendar for two leagues has to be constructed; besides the usual restrictions on the alternation of home- and away-games, one has to consider the fact that some pairs of teams in the two leagues share the same facilities and cannot play home-games simultaneously. Furthermore depending on the results in the first games, one of the leagues is divided for the last games into two subleagues. An optimal solution is constructed by using properties of oriented factorizations of complete graphs

Interplanetary Magnetic Field Guiding Relativistic Particles

The origin and the propagation of relativistic solar particles (0.5 to few Ge V) in the interplanetary medium remains a debated topic. These relativistic particles, detected at the Earth by neutron monitors have been previously accelerated close to the Sun and are guided by the interplanetary magnetic field (IMF) lines, connecting the acceleration site and the Earth. Usually, the nominal Parker spiral is considered for ensuring the magnetic connection to the Earth. However, in most GLEs the IMF is highly disturbed, and the active regions associated to the GLEs are not always located close to the solar footprint of the nominal Parker spiral. A possible explanation is that relativistic particles are propagating in transient magnetic structures, such as Interplanetary Coronal Mass Ejections (ICMEs). In order to check this interpretation, we studied in detail the interplanetary medium where the particles propagate for 10 GLEs of the last solar cycle. Using the magnetic field and the plasma parameter measurements (ACE/MAG and ACE/SWEPAM), we found widely different IMF configurations. In an independent approach we develop and apply an improved method of the velocity dispersion analysis to energetic protons measured by SoHO/ERNE. We determined the effective path length and the solar release time of protons from these data and also combined them with the neutron monitor data. We found that in most of the GLEs, protons propagate in transient magnetic structures. Moreover, the comparison between the interplanetary magnetic structure and the interplanetary length suggest that the timing of particle arrival at Earth is dominantly determined by the type of IMF in which high energetic particles are propagating. Finally we find that these energetic protons are not significantly scattered during their transport to Earth

EFFECT OF OSMOTIC DEHYDRATION IN THE APPLE (Pyrus malus) VARIETIES GALA, GOLD AND FUJI

Some raw material characteristics were evaluated in three apple varieties Gala, Gold and Fuji. The study was undertaken to collect information in order to identify the effects of initial tissue properties on mass transport phenomena in general, and osmotic processing responses in particular. The apples, obtained from the local market, were washed, peeled and cut into 10 mm cube. After this, the samples were dehydrated in sugar osmotic solution (50% w/w) at 30°C and 110 rpm of agitation. The ratio of foodstuff to osmotic solution was greater than 1:20. The mass transfer kinetics was measured in intervals of 20 minutes during 3 hours. The mass transfer kinetics of the different apple varieties has presented different behavior during the osmotic dehydration. The apples vs. Gala have presented the highest water loss and solid gain. The vs. Gold presented a lower tendency to solid uptake

High resolution modelling of aerosol dispersion regimes during the CAPITOUL field experiment: from regional to local scale interactions

High resolution simulation of complex aerosol particle evolution and gaseous chemistry over an atmospheric urban area is of great interest for understanding air quality and processes. In this context, the CAPITOUL (Canopy and Aerosol Particle Interactions in the Toulouse Urban Layer) field experiment aims at a better understanding of the interactions between the urban dynamics and the aerosol plumes. During a two-day Intensive Observational Period, a numerical model experiment was set up to reproduce the spatial distribution of specific particle pollutants, from the regional scales and the interactions between different cities, to the local scales with specific turbulent structures. Observations show that local dynamics depends on the day-regime, and may lead to different mesoscale dynamical structures. This study focuses on reproducing these fine scale dynamical structures, and investigate the impact on the aerosol plume dispersion. The 500-m resolution simulation manages to reproduce convective rolls at local scale, which concentrate most of the aerosol particles and can locally affect the pollutant dispersion and air quality

La prise en compte de la durabilité dans les stratégies marketing des PME : apports et limites

This paper examines how SME managers in the agro-food sector include sustainable development into their marketing strategy. We focus on the link between sustainable development and performance, the impact of environmental factors on their practices and the limits that they perceive when trying to include sustainability into their marketing strategy. More than a marketing strength, sustainability appears as important for the people who work in the SME. However, there are some limits. ...French Abstract : Nous examinons dans cet article comment des directeurs de PME agroalimentaires à fort ancrage territorial s’approprient la notion de développement durable et l’expriment dans leurs stratégies marketing. Nous examinons successivement leur vision du lien entre développement durable et performance, l’impact des caractéristiques environnementales sur leurs pratiques et les limites qu’ils perçoivent à cette volonté d’intégrer la durabilité dans leur stratégie au moment de sa mise en œuvre. Au-delà de l’argument commercial, la durabilité apparaît comme un levier intéressant du projet d’entreprise et de la mobilisation des salariés. Néanmoins, la démarche comporte aussi des limites.SUSTAINABILITY; MARKETING STRATEGY; FOOD SECTOR; SMALL FIRMS

ASSOCIATION OF LACTOFERRIN WITH SPECIFIC GRANULES IN RABBIT HETEROPHIL LEUKOCYTES

Lactoferrin has been identified in rabbit heterophil leukocytes on the basis of its immunological reactivity, electrophoretic mobility, acid-resistant iron-binding properties, and spectral characteristics. Leukocyte lactoferrin was found to be exclusively localized in the specific (secondary) granules, which have been resolved from other subcellular components by zonal differential centrifugation and by isopycnic equilibration