12 research outputs found

    The TeV Sun Rises: Discovery of Gamma rays from the Quiescent Sun with HAWC

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    We report the first detection of a TeV gamma-ray flux from the solar disk (6.3σ\sigma), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5--2.6 TeV spectrum is well fit by a power law, dN/dE = A(E/1 TeV)γA (E/1 \text{ TeV})^{-\gamma}, with A=(1.6±0.3)×1012A = (1.6 \pm 0.3) \times 10^{-12} TeV1^{-1} cm2^{-2} s1^{-1} and γ=3.62±0.14\gamma = -3.62 \pm 0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.Comment: 15 pages, 8 figures including supplementary material. Accepted for publication in Physical Review Letter

    First record of a freshwater cave sponge (Porifera, unknown gen. and sp.) in a cave inhabited by Astyanax cavefish in the Sierra de El Abra, San Luis Potosí, Mexico

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    The karstic cave, la Cueva de Los Sabinos, located in the Sierra de El Abra in the state of San Luis Potosí, Mexico, is mostly known for hosting a population of blind, depigmented Astyanax mexicanus cavefish. Herein, we report the discovery of a non-pigmented sponge (Porifera) in the final sump of this cave. No genus or species name could be attributed because we did not collect any specimen. Up to now, the sponge distribution seems restricted to a single pool in la Cueva de Los Sabinos, but further careful exploration of other pools of the cave as well as closely related cavities is warranted. To our knowledge, this observation constitutes the fourth report of a freshwater, white, cave-adapted sponge in the world and the first for Mexico and North America. It is also the eleventh troglobite species encountered in Los Sabinos. Our discovery confirms the exceptionally rich biodiversity of this cave ecosystem

    First Spanish series of intestinal transplantation in adult recipients Primera serie nacional de trasplante de intestino en receptores adultos

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    Background: short-bowel transplantation has experienced a substantial growth worldwide following improved results from the late 1990s on, and its coverage by Medicare. According to the International Registry (1985-2005), a total of 1,292 intestinal trasplants for 1,210 patients in 65 hospitals across 20 countries have been carried out thus far. Objective: to know short-term (6 months) results regarding patient and graft survival from the first Spanish series of intestinal transplants in adult recipients. Material and methods: we present our experience in the assessment of 20 potential candidates to short-bowel transplantation between June 2004 and October 2005. Of these, 10 patients were rejected and 4 were transplanted, which makes up the sample of our study. Results: to this date 5 transplants have been carried out in 4 patients (2 retransplants, 2 desmoid tumors, 1 short bowel syndrome after excision as a result of mesenteric ischemia). Upon study completion and after a mean follow-up of 180 days (range 90-190 days) all recipients are alive, and all grafts but one (75%) are fully operational, with complete digestive autonomy. All patients received induction with alemtuzumab except one, who received thymoglobulin; in all induction was initiated with no steroids. Conclusions: intestinal transplantation represents a therapeutic option that is applicable in our setting and valid for recipients with an indication who have no other feasible alternative to keep their intestinal failure under control
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