Nondestructive characterization of Antarctic micrometeorites collected at the Dome Fuji Station by synchrotron radiation X-ray fluorescence analysis

The bulk trace element composition (Ca, Ti, Cr, Mn, Ni Cu, Zn, Ge, Se, Rb, Sr, Y, Zr, Mo) of eighty-three Antarctic micrometeorites was nondestructively analyzed using synchrotron radiation X-ray fluorescence analysis (SR-XRF), and these elements were characterized in terms of their abundance ratio relative to Murchison matrix composition. The relationship between heating history and chemical composition is also examined. We found a complementary relationship among I-type, S-type and unmelted AMMs in the micrometeorites\u27 elemental abundance, which is consistent with the hypothesis that I-type and S-type spherules were separated from chondritic meteoroids

ROKU: a novel method for identification of tissue-specific genes

BACKGROUND: One of the important goals of microarray research is the identification of genes whose expression is considerably higher or lower in some tissues than in others. We would like to have ways of identifying such tissue-specific genes. RESULTS: We describe a method, ROKU, which selects tissue-specific patterns from gene expression data for many tissues and thousands of genes. ROKU ranks genes according to their overall tissue specificity using Shannon entropy and detects tissues specific to each gene if any exist using an outlier detection method. We evaluated the capacity for the detection of various specific expression patterns using synthetic and real data. We observed that ROKU was superior to a conventional entropy-based method in its ability to rank genes according to overall tissue specificity and to detect genes whose expression pattern are specific only to objective tissues. CONCLUSION: ROKU is useful for the detection of various tissue-specific expression patterns. The framework is also directly applicable to the selection of diagnostic markers for molecular classification of multiple classes

Contact metamorphism in the Malashan dome, North Himalayan gneiss domes, southern Tibet: An example of shallow extensional tectonics in the Tethys Himalaya

Combined petrographic, structural and geochronological study of the Malashan dome, one of the North Himalayan gneiss domes, reveals that it is cored by a Miocene granite, the Malashan granite, that intruded into the Jurassic sedimentary rocks of Tethys Himalaya. Two other granites in the area are referred to as the Paiku and Cuobu granites. New zircon SHRIMP U-Pb and muscovite and biotite 40Ar-39Ar dating show that the Paiku granite was emplaced during 22.2–16.2 Ma (average 19.3 ± 3.9 Ma) and cooled rapidly to 350–400 °C at around 15.9 Ma. Whole-rock granite chemistry suggests the original granitic magma may have formed by muscovite dehydration melting of a protolith chemically similar to the High Himalayan Crystalline Sequence. Abundant calcareous metasedimentary rocks and minor garnet-staurolite-biotite-muscovite ± andalusite schists record contact metamorphism by three granites that intruded intermittently into the Jurassic sediments between 18.5 and 15.3 Ma. Two stages of widespread penetrative ductile deformation, D1 and D2, can be defined. Microstructural studies of metapelites combined with geothermobarometry and pseudosection analyses yield P–T conditions of 4.8 ± 0.8 kbar at 550 ± 50 °C during a non-deformational stage between D1 and D2, and 3.1–4.1 kbar at 530–575 °C during syn- to post-D2. The pressure estimates for the syn- to post-D2 growth of andalusite suggest relatively shallow (depth of ∼15.2 km) extensional ductile deformation that took place within a shear zone of the South Tibetan Detachment System. Close temporal association between intrusion of the Malashan granite and onset of D2 suggests extension may have been triggered by the intrusion of the Malashan granite

Clinical Relevance of Parafoveal Intercapillary Spaces and Foveal Avascular Zone in Diabetic Retinopathy Without Macular Edema

Purpose: To investigate the clinical significance of intercapillary spaces on swept source optical coherence tomography angiography images in diabetic retinopathy. Methods: We retrospectively reviewed 110 eyes of 110 patients suffering from diabetic retinopathy without macular edema for whom 3 × 3 mm swept source optical coherence tomography angiography images centered on the fovea were obtained. Automatic image processing of the superficial slab images allowed us to define the areas encircled by retinal vessels as intercapillary spaces within the central 2-mm circle. We evaluated how the quantitative parameters of intercapillary spaces are associated with logMAR and feasible to diagnose diabetic macular ischemia. Results: Total counts (ρ = −0.419; P < 0.001) rather than morphologic parameters of the intercapillary spaces showed a significant correlation with logMAR. There were individual levels of correlations between logMAR and counts of intercapillary spaces in individual sectors. In particular, the summed numbers of the spaces in three highly significant sectors were more significantly associated with logMAR (ρ = −0.515; P < 0.001). Multivariate analyses confirmed that the number of the intercapillary spaces (β = −0.266; P = 0.016) and foveal avascular zone area (β = 0.227; P = 0.042) were related to logMAR. The clustering using the foveal avascular zone area and the number of intercapillary spaces revealed two major clusters; one had fewer intercapillary spaces (P < 0.001) and poorer logMAR (P < 0.001) than the other, with a wide range of the foveal avascular zone area. Conclusions: Decreased intercapillary spaces contribute to visual impairment in diabetic retinopathy and suggest one possible criterion of objective diagnosis of diabetic macular ischemia

Chemical effect on muonic atom formation through muon transfer reaction in benzene and cyclohexane samples

To investigate the chemical effect on the muon capture process through a muon transfer reaction from a muonic hydrogen atom, the formation rate of muonic carbon atoms is measured for benzene and cyclohexane molecules in liquid samples. The muon transfer rate to carbon atoms of the benzene molecule is higher than that to the carbon atoms of the cyclohexane molecule. Such a deviation has never been observed among those molecules for gas samples. This may be because the transfers occur from the excited states of muonic hydrogen atoms in the liquid system, whereas in the gas system, all the transfers occur from the 1s (ground) state of muon hydrogen atoms. The muonic hydrogen atoms in the excited states have a larger radius than those in the 1s state and are therefore considered to be affected by the steric hindrance of the molecular structure. This indicates that the excited states of muonic hydrogen atoms contribute significantly to the chemical effects on the muon transfer reaction

Infrared Imaging of z=2.43 Radio Galaxy B3 0731+438 with the Subaru Telescope - Detection of Hα\alpha Ionization Cones of a Powerful Radio Galaxy

We report on infrared imaging observations of the z=2.429 radio galaxy B3 0731+438 with the Subaru telescope. The images were taken with the K'-band filter and the 2.25 um narrow-band filter to examine the structure and properties of the Ha+[N II] 6548,6583 emission-line components. The Ha+[N II] emission-line image shows biconical lobes with an extent of 40 kpc, which are aligned with the radio axis. The rest-frame equivalent widths of the emission lines at these cones are as large as 1100 AA, and can be well explained by a gas-cloud model photoionized by power-law continuum radiation. The isotropic ionizing photon luminosity necessary to ionize the hydrogen gas in these cones amounts to 1e57(photons/s), which is larger than that in the majority of radio-loud QSOs. From these results, we propose that the Ha alignment effect in this object is produced by biconical gas clouds, which are swept up by the passage of radio jets, and are ionized by strong UV radiation from a hidden AGN. The continuum image consists of two components, a stellar-like point source and an extended diffuse galaxy. These are supposed to be a type-2 AGN and its host galaxy. The SED is fitted by a combination of spectra of a reddened dust-scattered AGN and an instantaneous starburst population of 500 Myr old. The stellar mass of the galaxy is estimated to be 3e11 M_solar, which is as large as that of typical 3C radio galaxies at z=1.Comment: 12 pages, 4 Postscript figures, uses PASJ2.sty, PASJ95.sty, PASJadd.sty. Accepted for publication in PASJ (2000

Clinically Significant Nonperfusion Areas on Widefield OCT Angiography in Diabetic Retinopathy

[Purpose] To investigate the distribution of clinically significant nonperfusion areas (NPAs) on widefield OCT angiography (OCTA) images in patients with diabetes. [Design] Prospective, cross-sectional, observational study. [Participants] One hundred and forty-four eyes of 114 patients with diabetes. [Methods] Nominal 20 × 23 mm OCTA images were obtained using a swept-source OCTA device (Xephilio OCT-S1), followed by the creation of en face images 20-mm (1614 pixels) in diameter centering on the fovea. The nonperfusion squares (NPSs) were defined as the 10 × 10 pixel squares without retinal vessels, and the ratio of eyes with the NPSs to all eyes in each square was referred to as the NPS ratio. The areas with probabilistic differences (APD) for proliferative diabetic retinopathy (PDR) and nonproliferative diabetic retinopathy (NPDR) (APD[PDR] and APD[NPDR]) were defined as sets of squares with higher NPS ratios in eyes with PDR and NPDR, respectively. The P ratio (NPSs within APD[PDR] but not APD[NPDR]/all NPSs) was also calculated. [Main Outcome Measures] The probabilistic distribution of the NPSs and the association with diabetic retinopathy (DR) severity. [Results] The NPSs developed randomly in eyes with mild and moderate NPDR and were more prevalent in the extramacular areas and the temporal quadrant in eyes with severe NPDR and PDR. The APD(PDR) was distributed mainly in the extramacular areas, sparing the areas around the vascular arcades and radially peripapillary capillaries. The APD(PDR) contained retinal neovascularization more frequently than the non-APD(PDR) (P = 0.023). The P ratio was higher in eyes with PDR than in those with NPDR (P < 0.001). The multivariate analysis designated the P ratio (odds ratio, 8.293 × 107; 95% confidence interval, 6.529 × 102–1.053 × 1013; P = 0.002) and the total NPSs (odds ratio, 1.002; 95% confidence interval, 1.001–1.003; P < 0.001) as independent risk factors of PDR. Most eyes with NPDR and 4-2-1 rule findings of DR severity had higher P ratios but not necessarily greater NPS numbers. [Conclusions] The APD(PDR) is uniquely distributed on widefield OCTA images, and the NPA location patterns are associated with DR severity, independent of the entire area of NPAs. [Financial Disclosure(s)] Proprietary or commercial disclosure may be found after the references