A sensitive cloud chamber without radioactive sources

We present a sensitive diffusion cloud chamber which does not require any radioactive sources. A major difference from a commonly used chamber is use of a heat sink as its bottom plate. A result of a performance test of the chamber is given.Comment: 8 pages, 8 figures, iopart.cls, figures and references adde

Excitation of the n=4 Levels of He⁺ by the Impact of H⁺, He⁺ and He²⁺ Ions

The emission cross sections of Hell (4→3) 4686 Å line by the incident beams of 0.5-1.5 MeV H⁺, 1.0-2.5 MeV He⁺ and 1.0-2.0 MeV He²⁺ are studied. By measuring the lateral distribution of the light intensity, the excitation of He⁺ (n＝4) levels is found to be caused by direct collision. The emission cross section by the proton impact is due to the ″ionization process″ and shows an E⁻¹ dependence, while that by the helium ion impact is due to the “charge transfer process” as well as the “ionization process” and shows a steeper energy dependence

Excitation Process of Helium Atoms by the Impact of 100-200 keV Protons

Excitation cross sections of some states of helium by the impact of 100-200 keV protons were studied under various excitation conditions. The lateral distributions of light source were also measured. In the higher target gas pressure region, the excitation of n¹P(n＝3, 4) levels are greatly increased by the effect of the imprisonment of resonance radiations, and the 4¹, ³D and 3³P levels are also influenced by the effect of a collisional transfer. The 4¹S state is mainly excited by a direct collision with incident protons even at the higher gas pressure

Destruxin E Decreases Beta-Amyloid Generation by Reducing Colocalization of Beta-Amyloid-Cleaving Enzyme 1 and Beta-Amyloid Protein Precursor

Alzheimer-disease-associated beta-amyloid (A beta) is produced by sequential endoproteolysis of beta-amyloid protein precursor (beta APP): the extracellular portion is shed by cleavage in the juxtamembrane region by beta-amyloid-cleaving enzyme (BACE)/beta-secretase, after which it is cleaved by presenilin (PS)/gamma-secretase near the middle of the transmembrane domain. Thus, inhibition of either of the secretases reduces A beta generation and is a fundamental strategy for the development of drugs to prevent Alzheimer disease. However, it is not clear how small compounds reduce A beta production without inhibition of the secretases. Such compounds are expected to avoid some of the side effects of secretase inhibitors. Here, we report that destruxin E (Dx-E), a natural cyclic hexadepsipeptide, reduces A beta generation without affecting BACE or PS/gamma-secretase activity. In agreement with this, Dx-E did not inhibit Notch signaling. We found that Dx-E decreases colocalization of BACE1 and beta APP, which reduces beta-cleavage of beta APP. Therefore, the data demonstrate that Dx-E represents a novel A beta-reducing process which could have fewer side effects than secretase inhibitors. Copyright (C) 2009 S. Karger AG, Base

Excitation of Nitrogen Molecule by the Impact of 80-160 kev Proton

Light emission from nitrogen molecules excited by the impact of 80-160 kev protons was studied over a wave length ranging from 3300 to 5400 Å. The lateral distributions of the light intensities were also measured. From the target gas pressure dependence of the light intensities and their lateral distributions, it was shown that the state B²Σ⁺ᴜ of N⁺₂ was excited by a direct proton collision, and that the state C³IIᵤ of N₂, having a singlet-triplet mixing, was excited by secondary processes

The Effect of Non-Axisymmetry of Magnetic Configurations on Radial Electric Field Transition Properties in the LHD

Transition property of the radial electric field (Er) in LHD have been theoretically investigated and also applied to explain experimental results. Especially, effects of the helicity of the magnetic configuration on the condition to realize the electron root are examined. Larger helicity makes the threshold collisionality higher. This is attributed to the nonlinear dependence of Γe(Er) in a low collisional regime. This interesting feature predicts that the threshold temperature becomes higher for a case of smaller helicity. The variation of the threshold density anticipated from the analysis for cases with different magnetic axis position is qualitatively verified in the density scan experiment

Discussion

The subsurface structure and sedimentary facies in the Beppu Bay basin were studied using 2D seismic and 3D high-resolution seismic (3D-HRS) surveys. A series of high-angle faults extend near the southern bay coast and are interpreted as active traces of the laterally moving Median Tectonic Line (MTL). A releasing bend of the MTL forms a pull-apart sag around the bay bottom accompanied by numerous normal fractures, whereas a compressional bulge is emerging on the southern side of the bay, suggesting complicated and transient stress states in the late Quaternary strata. Based on the general development history of the Hohi Volcanic Zone (HVZ), the lower, middle, and upper seismic horizons are assigned to 5–6 Ma (initial stage of the HVZ), 0.7 Ma, and 0.3 Ma, respectively. We identified three auxiliary reflectors within the upper part of the sediment pile and correlated them with oxygen isotope stages 15–11. These stratigraphic constraints are used to discuss paleoenvironments in the latest Pleistocene by means of an amplitude root mean square attribute analysis of the 3D-HRS data, which successfully delineated a buried river channel that was active during the last glacial period

Curated genome annotation of Oryza sativa ssp. japonica and comparative genome analysis with Arabidopsis thaliana

We present here the annotation of the complete genome of rice Oryza sativa L. ssp. japonica cultivar Nipponbare. All functional annotations for proteins and non-protein-coding RNA (npRNA) candidates were manually curated. Functions were identified or inferred in 19,969 (70%) of the proteins, and 131 possible npRNAs (including 58 antisense transcripts) were found. Almost 5000 annotated protein-coding genes were found to be disrupted in insertional mutant lines, which will accelerate future experimental validation of the annotations. The rice loci were determined by using cDNA sequences obtained from rice and other representative cereals. Our conservative estimate based on these loci and an extrapolation suggested that the gene number of rice is ~32,000, which is smaller than previous estimates. We conducted comparative analyses between rice and Arabidopsis thaliana and found that both genomes possessed several lineage-specific genes, which might account for the observed differences between these species, while they had similar sets of predicted functional domains among the protein sequences. A system to control translational efficiency seems to be conserved across large evolutionary distances. Moreover, the evolutionary process of protein-coding genes was examined. Our results suggest that natural selection may have played a role for duplicated genes in both species, so that duplication was suppressed or favored in a manner that depended on the function of a gene