Observations of quiet-time moderate midlatitude L-band scintillation in association with plasma bubbles

Observations of moderate night time amplitude scintillation on the GPS L1C/A signal were recorded at the midlatitude station of Nicosia, corresponding geographic latitude and longitude of 35.18˚N and 33.38˚E respectively, on a geomagnetically quiet day. The variations of slant total electron content (STEC) and amplitude scintillation index (S4) on the night of June 12, 2014, indicate the presence of electron density depletions accompanying scintillation occurrence. The estimated apparent horizontal drift velocity and propagation direction of the plasma depletions are consistent with those observed for the equatorial plasma bubbles, thus suggesting that the moderate amplitude L-band scintillation observed over Nicosia may be associated with the extension of such plasma bubbles. The L-band scintillation occurrence was concurrent with the observations of range spread F on the ionograms recorded by the digisonde at Nicosia. The height–time–intensity plot generated using the ionogram data also showed features which can be attributed to off-angle reflections from electron density depletions, thus corroborating the STEC observations. This observation suggests that the midlatitude ionosphere is more active even during geomagnetically quiet days than previously thought and that further studies are necessary. This is particularly relevant for the GNSS user community and related applications

Update on a pilot study: Flumeltbi peripheral blood HLAhaploidentical stem cell transplantation with post-transplant cyclophosphamide and bortezomib (Cy2Bor3)

Background: Bortezomib (Bor) can inhibit the proliferation of dendritic cells (DCs) and block the expression of co-receptors CD80, CD86 and secretion of cytokines IL-12 and TNF-α and hence the ability of DCs to activate T cells. We started a pilot study incorporating the addition of bortezomib to post-transplant cyclophosphamide (PTCY) in the setting of peripheral blood (PB) HLA-haploidentical stem cell transplantation (Haplo-SCT). Methods: This is a single center open label pilot study. Eligible patients received Fludarabine Melphalan TBI 200 cGy as conditioning followed by haplo-SCT and PTCY. Bor was administered at 1.3mg/m2 on day+1, 4 and 7. Tacrolimus and MMF were started at day+5. Results: Seven patients were enrolled so far, five males and 2 females. Median age was 58 years (26-60). Donors were 3 brothers, 3 sons and 1 mother. Disease risk index was high in 3, intermediate in 3 and low in 1. Three patients had AML, two had ALL and MM, one had ALL and one had CML. CMV recipient status was negative in one and positive in 6. Median HCT-CI was 3(1-4). Median CD34 and CD3 infused were 4.13 x10-6 and 1.7x10-8/ kg recipient respectively, all were cryopreserved except 2. Four patients had CRS before Cy infusion with ASTCT grade of 1. Six patients had grade 3 hypokalemia around day+ 4-5. Five patients had grade 3 mucositis and 2 had grade 1. Four patients had neutropenic fever and one patient had engraftment fever. Median neutrophils and platelets engraftment were 16 and 26 days respectively. Chimerism post SCT was \u3e =99% donor at day 30 for all patients. Six patients are off tacrolimus with median time to be off it was 187.5 days. Five pts had aGVHD with maximum grade of I in 3 patients, II in one patient and III in one patient at a median 50days post SCT. None developed early hematuria, four had late hematuria with highest grade of 4. Two patients were positive for BK virus. One patient had reactivation of CMV, 2 had EBV and one had adenovirus, all resolved. Three pts had HHV6 that resolved. Of the 5 patients who were evaluable, one developed moderate chronic GVHD. So far the median time to follow up is 455 days (70-1239) with relapse and subsequently death in one patient who had high risk AML with 3 different inductions prior to SCT. . At 1 year for 4 evaluable patients IgG were \u3e400 mg/dl and CD4 \u3e 350 cells/ul. Conclusions: Cy2Bor3 post PB Haplo-SCT was well tolerated. Although small number of patients and limited but encouraging results so far. The trial is ongoing

Size-Dependent Materials Properties Toward a Universal Equation

Due to the lack of experimental values concerning some material properties at the nanoscale, it is interesting to evaluate this theoretically. Through a “top–down” approach, a universal equation is developed here which is particularly helpful when experiments are difficult to lead on a specific material property. It only requires the knowledge of the surface area to volume ratio of the nanomaterial, its size as well as the statistic (Fermi–Dirac or Bose–Einstein) followed by the particles involved in the considered material property. Comparison between different existing theoretical models and the proposed equation is done

DIFFUSION OF ELECTRONS AND HOLES IN DOPED SEMICONDUCTORS AT HIGH LATTICE AND ELECTRONIC TEMPERATURES

Il est montré comment les propriétés de diffusion des électrons et des trous sont modifiées lorsque leur densité et la température du réseau sont élevées. En particulier, il en résulte que le transfert d'énergie des électrons au réseau dépend fortement des conditions expérimentales : le chauffage est plus efficace à basse qu'à haute puissance. La création de défauts par l'irradiation laser peut conduire à l'existence d'un état métastable de longue durée de vie près de la surface irradiée du semiconducteur.It is shown how the diffusion properties of electrons and holes are modified when their density and the lattice temperature are high. In particular, it arises that the transfer of energy from the electrons to the lattice depends strongly on experimental conditions : heating is more efficient at low than at high power. Laser-induced defects may result in the existence of a long-lived metastable state near the irradiated surface of the semiconductor

On the melting of polyhedral elemental nanosolids

The phase diagram of nanoparticles is known to be a function of their size. Since this dependence is also a function of the surface to volume ratio and of the surface tensions, it is expected that it varies with the shape of the nanoparticles. The variation of the melting temperature of polyhedral elemental nanosolids is studied theoretically. It turns out that, in most cases, the size variation of the melting temperature of a sphere is less than for the other shapes. However, there is no general rule regarding the order of the shape parameters of the polyhedra