47 research outputs found
Observations of High Energy Cosmic-Ray Electrons from 30 GeV to 3 TeV with Emulsion Chambers
We have performed a series of cosmic-ray electron observations using the
balloon-borne emulsion chambers since 1968. While we previously reported the
results from subsets of the exposures, the final results of the total exposures
up to 2001 are presented here. Our successive experiments have yielded the
total exposure of 8.19 m^2 sr day at the altitudes of 4.0 - 9.4 g/cm^2. The
performance of the emulsion chambers was examined by accelerator beam tests and
Monte-Carlo simulations, and the on-board calibrations were carried out by
using the flight data. In this work we present the cosmic-ray electron spectrum
in the energy range from 30 GeV to 3 TeV at the top of the atmosphere, which is
well represented by a power-law function with an index of -3.28+-0.10. The
observed data can be also interpreted in terms of diffusive propagation models.
The evidence of cosmic-ray electrons up to 3 TeV suggests the existence of
cosmic-ray electron sources at distances within ~1 kpc and times within ~1x10^5
yr ago.Comment: 38 pages, 10 figures, 3 tables, Accepted for publication in Ap
High energy electron observation by Polar Patrol Balloon flight in Antarctica
We accomplished a balloon observation of the high-energy cosmic-ray electrons in 10-1000GeV to reveal the origin and the acceleration mechanism. The observation was carried out for 13 days at an average altitude of 35km by the Polar Patrol Balloon (PPB) around Antarctica in January 2004. The detector is an imaging calorimeter composed of scintillating-fiber belts and plastic scintillation counters sandwiched between lead plates. The geometrical factor is about 600cm^2sr, and the total thickness of lead absorber is 9 radiation lengths. The performance of the detector has been confirmed by a test flight at the Sanriku Balloon Center and by an accelerator beam test using the CERN-SPS (Super Proton Synchrotron at CERN). The new telemetry system using the Iridium satellite, the power system supplied by solar panels and the automatic flight level control operated successfully during the flight. We collected 5.7×10^3 events over 100GeV, and selected the electron candidates by a preliminary data analysis of the shower images. We report here an outline of both detector and observation, and the first result of the electron energy spectrum over 100GeV obtained by an electronic counter
Palladium-Catalyzed Aerobic Anti-Markovnikov Oxidation of Aliphatic Alkenes to Terminal Acetals
A Case of Paroxysmal Kinesigenic Dyskinesia with Complex Partial Seizure Probably Associated with Amygdala Enlargement
Evaluating the Role of Rheumatoid Factors for the Development of Rheumatoid Arthritis in a Mouse Model with a Newly Established ELISA System
Urinary concentrations of neonicotinoid insecticides were related to renal tubular dysfunction and neuropsychological complaints in Dry-zone of Sri Lanka
International audienceAbstract Neonicotinoids are systemic insecticides used since the 1990’s , that possess renal tubular toxicity. We conducted a field-based descriptive study in the North Central Dry-zone of Sri Lanka, where chronic kidney disease (CKD) of unknown etiology has been increasing since the 1990’s. To elucidate the relationship between renal tubular dysfunctions and urinary neonicotinoids concentrations, we collected spot urine samples from15 CKD patients, 15 family members, and 62 neighbors in 2015, analyzed two renal tubular biomarkers, Cystatin-C and L-FABP, quantified seven neonicotinoids and a metabolite N -desmethyl-acetamiprid by LC–MS/MS; and we investigated their symptoms using a questionnaire. Cystatin-C and L-FABP had a positive correlation ( p 70 μg/gCre, n = 7), higher urinary concentration of dinotefuran ( p = 0.009), and in Zero Cystatin-C group (< LOQ, n = 7), higher N -desmethyl-acetamiprid ( p = 0.013), dinotefuran ( p = 0.049), and thiacloprid ( p = 0.035), and more complaints of chest pains, stomachache, skin eruption and diarrhea ( p < 0.05) were found than in Normal Cystatin-C group (n = 78). Urinary neonicotinoids may be one of the potential risk factors for renal tubular dysfunction in this area