Cosmic ray oriented performance studies for the JEM-EUSO first level trigger

JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E > 5 ⋅ 1019 eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduce the data load in the presence of both atmospheric and human activity related background light, yet retain the rare cosmic ray events recorded in the telescope. We report the performance in offline testing of the first level trigger algorithm on data from JEM-EUSO prototypes and laboratory measurements observing different light sources: data taken during a high altitude balloon flight over Canada, laser pulses observed from the ground traversing the real atmosphere, and model landscapes reproducing realistic aspect ratios and light conditions as would be seen from the ISS itself. The first level trigger logic successfully kept the trigger rate within the permissible bounds when challenged with artificially produced as well as naturally encountered night sky background fluctuations and while retaining events with general air-shower characteristics

Guérison complète de l’hépatite virale C : une réalité

La réponse virologique complète soutenue est actuellement synonyme de guérison de l’infection virale C [1, 2}. Néanmoins, nous pensons que le degré de guérison est à nuancer en fonction de la réponse histologique. En effet, le terme de « guérison complète » doit être à notre avis, réservé à la restitution ad integrum du foie. Les auteurs rapportent 7 cas de régression complète de fibrose (A0F0), au minimum 2 ans après l’éradication virale

Elaboration and characterization of dental plasters obtained from a Moroccan gypsum

Three experimental batches of  plaster elaborated from a Moroccan gypsum were characterized by conductimetry, dimensional variations measurements during setting and mechanical tests. Comparison with commercial dental plasters are undertaken to check whether these experimental materials possess good characteristics for dentistry applications

Factors influencing extramedullary relapse after allogeneic transplantation for multiple myeloma

International audienc

Inactivation of Lsd1 triggers senscence in trophoblast stem cells by induction of Sirt4

Coordination of energy metabolism is essential for homeostasis of stem cells, whereas an imbalance in energy homeostasis causes disease and accelerated aging. Here we show that deletion or enzymatic inactivation of lysine-specific demethylase 1 (Lsd1) triggers senescence in trophoblast stem cells (TSCs). Genome-wide transcriptional profiling of TSCs following Lsd1 inhibition shows gene set enrichment of aging and metabolic pathways. Consistently, global metabolomic and phenotypic analyses disclose an unbalanced redox status, decreased glutamine anaplerosis and mitochondrial function. Loss of homeostasis is caused by increased expression of sirtuin 4 (Sirt4), a Lsd1-repressed direct target gene. Accordingly, Sirt4 overexpression in wild-type TSCs recapitulates the senescence phenotype initiated by Lsd1 deletion or inhibition. Inversely, absence of Lsd1 enzymatic activity concomitant with knockdown of Sirt4 reestablishes normal glutamine anaplerosis, redox balance and mitochondrial function. In conclusion, by repression of Sirt4, Lsd1 directs the epigenetic control of TSC immortality via maintenance of metabolic flexibility

Am J Hematol

To the Editor: Thrombotic thrombocytopenic purpura (TTP) is a specific form of thrombotic microangiopathy (TMA) characterized by thrombocytopenia, erythrocyte fragmentation, and widespread microvascular thrombi responsible for multi-organ failure of variable severity [1]. Surprisingly, while a profound thrombocytopenia is a typical feature of the disease, severe hemorrhage is a rare cause of mortality. Nevertheless, in case of severe bleeding or when an invasive procedure is needed (i.e., catheter insertion, spinal puncture), platelets transfusion may be required, although sudden clinical deteriorations and fatalities suggestive of a worsening of TTP within few hours after a platelet transfusion were reported [2,3]. To date, controversies remain on the effect of platelet transfusions during TTP [4–6]. In light of the uncertain risk of platelet transfusions in TTP and the lack of recently published data, we retrospectively reviewed admission data of all TTP patients with a severe acquired ADAMTS13 deficiency (\textless10% of activity in normal plasma) enrolled in the French TMA Reference Centre registry, in order to better assess the risk of platelet transfusions at the acute phase of TTP. ..