Argentina spectral-agronomic multitemporal data set

A multitemporal LANDSAT spectral data set was created. The data set is over five 5 nm-by-6 nm areas over Argentina and contains by field, the spectral data, vegetation type and cloud cover information

The ALTCRISS project on board the International Space Station

The Altcriss project aims to perform a long term survey of the radiation environment on board the International Space Station. Measurements are being performed with active and passive devices in different locations and orientations of the Russian segment of the station. The goal is to perform a detailed evaluation of the differences in particle fluence and nuclear composition due to different shielding material and attitude of the station. The Sileye-3/Alteino detector is used to identify nuclei up to Iron in the energy range above 60 MeV/n. Several passive dosimeters (TLDs, CR39) are also placed in the same location of Sileye-3 detector. Polyethylene shielding is periodically interposed in front of the detectors to evaluate the effectiveness of shielding on the nuclear component of the cosmic radiation. The project was submitted to ESA in reply to the AO in the Life and Physical Science of 2004 and data taking began in December 2005. Dosimeters and data cards are rotated every six months: up to now three launches of dosimeters and data cards have been performed and have been returned with the end of expedition 12 and 13.Comment: Accepted for publication on Advances in Space Research http://dx.doi.org/10.1016/j.asr.2007.04.03

Katz Model Prediction of \u3ci\u3eCaenorhabditis elegans\u3c/i\u3e Mutagenesis on STS-42

The Katz track structure model has been applied to describe recessive lethal mutagenesis in the nematode Caenorhabditis elegans after exposure to heavy ions. Based on models of the cosmic-ray environment and heavy-ion transport, mutation rates for the International Microgravity Laboratory 1 (IML-1) experiment on the Space Transportation System 42 (STS-42) are predicted and the results are discussed

Katz Model Prediction of \u3ci\u3eCaenorhabditis elegans\u3c/i\u3e Mutagenesis on STS-42

The Katz track structure model has been applied to describe recessive lethal mutagenesis in the nematode Caenorhabditis elegans after exposure to heavy ions. Based on models of the cosmic-ray environment and heavy-ion transport, mutation rates for the International Microgravity Laboratory 1 (IML-1) experiment on the Space Transportation System 42 (STS-42) are predicted and the results are discussed

Absolute rigidity spectrum of protons and helium nuclei above 10 GV/c

Proton and helium nuclei differential spectra were gathered with a balloon borne magnet spectrometer. The data were fitted to the assumption that the differential flux can be represented by a power law in rigidity. In the rigidity range 10 to 25 GV/c the spectral indices were found to be -(2.74 plus or minus 0.04) for protons and -(2.71 plus or minus 0.05) for helium nuclei. A brief discussion is given by systematic errors

Observation of cosmic ray positrons from 5 to 25 GeV

The positron data gathered in conjunction with electron data published elsewhere is reported. The basic recognition scheme was to look for low mass positive particles that cause a cascade in a 7 radiation length shower counter. The mass criteria is imposed by selecting particles that were accompanied by Cherenkov light but whose rigidity was below the proton Cherenkov threshold. Thus the proton Cherenkov threshold represents an upper limit to the range of the experiment

Randomized trial of conventional transseptal needle versus radiofrequency energy needle puncture for left atrial access (the TRAVERSE-LA study).

BackgroundTransseptal puncture is a critical step in achieving left atrial (LA) access for a variety of cardiac procedures. Although the mechanical Brockenbrough needle has historically been used for this procedure, a needle employing radiofrequency (RF) energy has more recently been approved for clinical use. We sought to investigate the comparative effectiveness of an RF versus conventional needle for transseptal LA access.Methods and resultsIn this prospective, single-blinded, controlled trial, 72 patients were randomized in a 1:1 fashion to an RF versus conventional (BRK-1) transseptal needle. In an intention-to-treat analysis, the primary outcome was time required for transseptal LA access. Secondary outcomes included failure of the assigned needle, visible plastic dilator shavings from needle introduction, and any procedural complication. The median transseptal puncture time was 68% shorter using the RF needle compared with the conventional needle (2.3 minutes [interquartile range {IQR}, 1.7 to 3.8 minutes] versus 7.3 minutes [IQR, 2.7 to 14.1 minutes], P = 0.005). Failure to achieve transseptal LA access with the assigned needle was less common using the RF versus conventional needle (0/36 [0%] versus 10/36 [27.8%], P < 0.001). Plastic shavings were grossly visible after needle advancement through the dilator and sheath in 0 (0%) RF needle cases and 12 (33.3%) conventional needle cases (P < 0.001). There were no differences in procedural complications (1/36 [2.8%] versus 1/36 [2.8%]).ConclusionsUse of an RF needle resulted in shorter time to transseptal LA access, less failure in achieving transseptal LA access, and fewer visible plastic shavings

Radio-emitting electrons and cosmic ray confinement

The propagation of cosmic ray electrons in the framework of the Disk-Halo diffusion model in which the diffusion coefficientD ∝ z δ E μ (where z is the distance from the galactic plane and E is the energy), and the magnetic field H∝z - ξ has been examined by making use of the recently available radio data up to 8 GHz toward the anticenter (A) and halo minimum (M). The following inferences are then made. From the difference in the frequency at which steepening occurs in the radio spectra toward A and H, it is found that the observations are consistent with the magnetic field decreasing with z such that ξ=0.24-0.37. An electron injection spectrum with a single power law down to energies well below 1 GeV cannot explain satisfactorily the observed radio spectra. All observations, however, can be understood in a self consistent way if the observed steepening of the radio spectra, and hence the interstellar electron spectrum, is due partly to the deviation in the power law electron injection spectrum below a few GeV and partly to the first break arising from electron energy losses occurring in the same energy region. In this case, using the value of ξ obtained above and a value of μ=0.3-0.6, it is found that the spectral index γ 0 of the injected electrons above a few GeV has a value between 1.9 and 2.3 and the index δ a value between 0.5 and 1. Further, if the electrons and protons have the same spectral shape at injection, then γ 0=2.1-2.3

The Absolute Spectra of Galactic Cosmic Rays at Solar Minimum and Their Implications for Manned Spaceflight

The radiation dose from galactic cosmic rays during a proposed mission to Mars is near the annual dose limit for the crew. Since the absolute spectra of galactic cosmic rays critically influences mission planning and spacecraft design, these spectra must be determined as accurately as possible. We have fit published measurements with solutions of the spherically symmetric diffusion equation to make accurate representations of the spectra. We report preliminary determinations on the absolute differential energy spectra at 1 AU and discuss the implications for the proposed missions to Mars