We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic ...Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.
The assessment of the environmental quality of coastal lagoons is rather difficult as their intrinsic high variability limits the power of analytical chemistry and ecotoxicological approaches. Aim of ...the present work was to integrate geochemical and biological data which were simultaneously collected from the Pialassa Baiona lagoon (Ravenna, Italy), and evaluate the usefulness of a biomonitoring strategy based on sentinel organisms and biomarkers. Geochemical analysis on suspended, surface, and subsurface sediments were performed at five different sites of the lagoon; moreover the heavy metal bioaccumulation and a battery of biomarkers was evaluated in Mytilus galloprovincialis transplanted in the same sites. Heavy metals appeared to be diffused throughout the lagoon reaching higher levels in the southernmost sites, and mainly concentrated in suspended sediments. Lysosome membrane stability, neutral lipid and lipofuscin accumulation, and metallothionein levels in mussels indicated the development of a stress syndrome in animals exposed to the polluted sites.
A new generation magnetic spectrometer in space will open the opportunity to investigate the frontiers in direct high-energy cosmic ray measurements and to precisely measure the amount of the rare ...antimatter component in cosmic rays beyond the reach of current missions. We propose the concept for an Antimatter Large Acceptance Detector In Orbit (ALADInO), designed to take over the legacy of direct measurements of cosmic rays in space performed by PAMELA and AMS-02. ALADInO features technological solutions conceived to overcome the current limitations of magnetic spectrometers in space with a layout that provides an acceptance larger than 10 m2 sr. A superconducting magnet coupled to precision tracking and time-of-flight systems can provide the required matter–antimatter separation capabilities and rigidity measurement resolution with a Maximum Detectable Rigidity better than 20 TV. The inner 3D-imaging deep calorimeter, designed to maximize the isotropic acceptance of particles, allows for the measurement of cosmic rays up to PeV energies with accurate energy resolution to precisely measure features in the cosmic ray spectra. The operations of ALADInO in the Sun–Earth L2 Lagrangian point for at least 5 years would enable unique revolutionary observations with groundbreaking discovery potentials in the field of astroparticle physics by precision measurements of electrons, positrons, and antiprotons up to 10 TeV and of nuclear cosmic rays up to PeV energies, and by the possible unambiguous detection and measurement of low-energy antideuteron and antihelium components in cosmic rays.
Resumen: El objetivo del presente trabajo fue evaluar el efecto antiparasitario de Plantago lanceolata (Llantén) frente a Lolium multiflorum (Raigrás anual). Se utilizaron 40 corderos Merino ...Australiano de 7 meses, clínicamente sanos y castrados. Dos grupos tomados al azar de 20 animales fueron asignados, después de ser dosificados con un antihelmíntico de amplio espectro, a 1 hectárea de Plantago lanceolata cv. Tonic y a 1 hectárea de Lolium multiflorum cv. Pronto, las que se fraccionaron en tres parcelas de 0,33 hectárea cada una y se manejaron con 14 días de ocupación y 28 días de descanso. La disponibilidad inicial de forraje fue de 1380 kg/ha MS para Llantén y 1441 kg/ha MS para Raigrás. La evolución de la infección parasitaria y el peso vivo se realizó cada 14 días y se estudiaron mediante análisis de varianza y diferencias de medias. Los géneros parasitarios se evaluaron cada 28 días y el hematocrito se determinó en ocasión del quinto muestreo. Ambos grupos mantuvieron niveles parasitarios leves y culminaron con iguales cargas parasitarias. Los dos grupos de animales ganaron peso durante todo el experimento con excepción del segundo y noveno muestreo. No se observaron diferencias estadísticas en ninguno de los muestreos. Los géneros predominantes fueron Haemonchus spp. y Trichostrongylus spp., y en menor proporción Ostertagia spp., Cooperia spp. y Oesophagostomum spp. En todos los casos se determinaron valores normales de hematocrito y una correlación negativa con el HPG. Se concluye que corderos con niveles de parasitosis leves son capaces de realizar buenas ganancias de peso vivo en pasturas con altos niveles nutritivos y que Plantago lanceolata es capaz de generar adecuada productividad animal. No logró ser demostrado que los taninos condensados hayan actuado como controladores de la parasitosis.
Understanding the time-dependent relationship between the Sun's variability and cosmic rays (GCR) is essential for developing predictive models of energetic radiation in space. When traveling inside ...the heliosphere, GCRs are affected by magnetic turbulence and solar wind disturbances which result in the so-called solar modulation effect. To investigate this phenomenon, we have performed a data-driven analysis of the temporal dependence of the GCR flux over the solar cycle. With a global statistical inference of GCR data collected in space by AMS-02 and PAMELA on monthly basis, we have determined the rigidity and time dependence of the GCR diffusion mean free path. Here we present our results for GCR protons, we discuss their interpretation in terms of basic processes of particle transport and their relations with the dynamics of the heliospheric plasma.
To report the use of an aortic endograft to treat a ruptured false aneurysm at the anastomosis of an aortofemoral bypass graft.
A 68-year-old man with a 30-year-old aorto-right femoral bypass and ...multiple comorbidities was admitted to the hospital complaining of acute abdominal pain. Imaging identified a 60-mm ruptured aortic false aneurysm with associated retroperitoneal hematoma, a 9-cm right femoral false aneurysm, and a calcified 23-mm left common iliac aneurysm. Two slightly overlapping Vanguard straight stent-grafts were implanted in the aorta and left common iliac artery in an emergency procedure owing to the patient's high surgical risk. The anastomotic false aneurysm and the bypass were excluded. A left-to-right femorofemoral bypass was performed to re-establish flow to the right femoral artery with ligation of the external iliac artery. The patient recovered uneventfully. He remained well with a successful repair until his death of a myocardial infarction 6 months after the procedure.
Endovascular grafting can be used successfully for the urgent treatment of aortic false aneurysm rupture.
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