241 research outputs found

    First Evidence of a Retrograde Orbit of Transiting Exoplanet HAT-P-7b

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    We present the first evidence of a retrograde orbit of the transiting exoplanet HAT-P-7b. The discovery is based on a measurement of the Rossiter-McLaughlin effect with the Subaru HDS during a transit of HAT-P-7b, which occurred on UT 2008 May 30. Our best-fit model shows that the spin-orbit alignment angle of this planet is \lambda = -132.6 (+10.5, -16.3) degrees. The existence of such a retrograde planet have been predicted by recent planetary migration models considering planet-planet scattering processes or the Kozai migration. Our finding provides an important milestone that supports such dynamic migration theories.Comment: PASJ Letters, in press [13 pages

    Spin-Orbit Alignment of the TrES-4 Transiting Planetary System and Possible Additional Radial Velocity Variation

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    We report new radial velocities of the TrES-4 transiting planetary system, including observations of a full transit, with the High Dispersion Spectrograph of the Subaru 8.2m telescope. Modeling of the Rossiter-McLaughlin effect indicates that TrES-4b has closely aligned orbital and stellar spin axes, with λ=6.3∘±4.7∘\lambda = 6.3^{\circ} \pm 4.7^{\circ}. The close spin-orbit alignment angle of TrES-4b seems to argue against a migration history involving planet-planet scattering or Kozai cycles, although there are two nearby faint stars that could be binary companion candidates. Comparison of our out-of-transit data from 4 different runs suggest that the star exhibits radial velocity variability of ∼\sim20 ms^-1 in excess of a single Keplerian orbit. Although the cause of the excess radial velocity variability is unknown, we discuss various possibilities including systematic measurement errors, starspots or other intrinsic motions, and additional companions besides the transiting planet.Comment: 10 pages, 3 figures, 3 tables, PASJ in pres

    Accuracy of Acetabular Cup Implantation, as a Function of Body Mass Index and Soft-tissue Thickness, with a Mechanical Intraoperative Support Device: A Retrospective Observational Study

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    HipCOMPASS, a mechanical intraoperative support device used in total hip arthroplasty (THA), improves the cup-alignment accuracy. However, the alignment accuracy achieved by HipCOMPASS has not been specifically examined in obese patients. In this study, we retrospectively evaluated the relation between alignment accuracy and several obesity-related parameters in 448 consecutive patients who underwent primary THA using HipCOMPASS. We used computed tomography (CT) to measure the preoperative soft-tissue thickness of the anterior-superior iliac spine (ASIS) and pubic symphysis and the differences between preoperative and postoperative cup angle based on the cup-alignment error. We found significant correlations between the absolute value of radiographic anteversion difference and body mass index (r = 0.205), ASIS thickness (r = 0.419), and pubic symphysis thickness (r = 0.434). The absolute value of radiographic inclination difference was significantly correlated with ASIS (r = 0.257) and pubic symphysis thickness (r = 0.202). The receiver operating characteristic curve showed a pubic symphysis thickness of 37.2 mm for a β‰₯ 5Β° implantation error in both radiographic inclination and anteversion simultaneously. The cup-alignment error for HipCOMPASS was large in patients whose pubic symphysis thickness was β‰₯ 37.2 mm on preoperative CT. Our results indicate that methods other than HipCOMPASS, including computed tomography-based navigation systems, might be preferable in obese patients

    Measurements of Stellar Inclinations for Kepler Planet Candidates II: Candidate Spin-Orbit Misalignments in Single and Multiple-Transiting Systems

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    We present a test for spin-orbit alignment for the host stars of 25 candidate planetary systems detected by the {\it Kepler} spacecraft. The inclination angle of each star's rotation axis was estimated from its rotation period, rotational line broadening, and radius. The rotation periods were determined using the {\it Kepler} photometric time series. The rotational line broadening was determined from high-resolution optical spectra with Subaru/HDS. Those same spectra were used to determine the star's photospheric parameters (effective temperature, surface gravity, metallicity) which were then interpreted with stellar-evolutionary models to determine stellar radii. We combine the new sample with the 7 stars from our previous work on this subject, finding that the stars show a statistical tendency to have inclinations near 90∘^\circ, in alignment with the planetary orbits. Possible spin-orbit misalignments are seen in several systems, including three multiple-planet systems (KOI-304, 988, 2261). Ideally these systems should be scrutinized with complementary techniques---such as the Rossiter-McLaughlin effect, starspot-crossing anomalies or asteroseismology---but the measurements will be difficult owing to the relatively faint apparent magnitudes and small transit signals in these systems.Comment: 11 pages, 9 figures, accepted for publication in Ap

    A strong association of axillary osmidrosis with the wet earwax type determined by genotyping of the ABCC11 gene

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    <p>Abstract</p> <p>Background</p> <p>Two types of cerumen occur in humans: the wet type with brownish, sticky earwax, and the dry type with a lack of or reduced ceruminous secretion. The wet type is common in populations of European and African origin, while the dry type is frequently seen in Eastern Asian populations. An association between axillary odor and the wet-type earwax was first identified approximately 70 years ago. The data were based on a phenotypical analysis of the two phenotypes among the Japanese by a researcher or by self-declaration of the subjects examined, and were not obtained using definite diagnostic methods. Recently, we identified a single-nucleotide polymorphism (SNP; rs17822931) of the <it>ABCC11 </it>gene as the determinant of the earwax types. In the present study, to determine whether the SNP can serve as a diagnostic marker for axillary osmidrosis (AO), we examined genotypes at rs17822931 in 79 Japanese AO individuals. AO was defined here as a clinical condition of individuals with a deep anxiety regarding axillary odor and had undergone the removal of bilateral axillary apocrine glands.</p> <p>Results</p> <p>A comparison of the frequencies of genotypes at rs17822931 in the 79 AO individuals and in 161 Japanese from the general population showed that AO was strongly associated with the wet earwax genotype. A total of 78 (98.7%) of 79 AO patients had either the GG or GA genotype, while these genotypes were observed in 35.4% (57/161) of the subjects from the general population (<it>p </it>< 1.1 Γ— 10<sup>-24</sup>, by Fisher's exact test).</p> <p>Conclusion</p> <p>The strong association between the wet-earwax associated <it>ABCC11-</it>genotypes (GG and GA) and AO identified in this study indicates that the genotypes are good markers for the diagnosis of AO. In addition, these results suggest that having the allele G is a prerequisite for the axillary odor expression. In other words, the ABCC11 protein may play a role in the excretory function of the axillary apocrine gland. Together, these results suggest that when an AO individual visiting a hospital is diagnosed with dry-type earwax by <it>ABCC11</it>-genotyping, surgical removal of their axillary glands may not be indicated.</p

    Perspective on Therapeutic Strategies of Leukemia Treatment β€” Focus on Arsenic Compounds

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    Leukemia is a type of cancer of the body’s blood-forming tissues, including the bone marrow and the lymphatic system. Treatments for leukemia are complex, depending upon the type of leukemia and other factors. Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia (AML) and accounts for approximately 10-15% of all cases of AML in adults. Arsenic and its compounds are widely distributed in the environment and have been used medicinally for over 2,000 years. In fact, investigators from China and the USA have demonstrated that treatment with ATO (As2O3, AsIII) results in complete remission in 90% of relapsed APL patients since mid-1990s. Moreover, As2S2 or As4S4, also known as realgar, has been gaining increasing attention and is traditionally used to treat certain types of hematological disorders including chronic myeloid leukemia (CML), AML, myelodysplastic syndrome (MDS) and MDS/AML in China. In this chapter, we first highlight the pharmacokinetics of ATO and realgar in leukemia patients and/or healthy volunteer. We will further summarize the detailed mechanisms underlying the cytocidal effects of these arsenic compounds. We also provide detailed insight into potential future clinical application of those promising candidates endowed with potent antitumor activities in view of combination with arsenic compounds

    Isolation and Characterization of Renal Erythropoietin-Producing Cells from Genetically Produced Anemia Mice

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    Understanding the nature of renal erythropoietin-producing cells (REPs) remains a central challenge for elucidating the mechanisms involved in hypoxia and/or anemia-induced erythropoietin (Epo) production in adult mammals. Previous studies have shown that REPs are renal peritubular cells, but further details are lacking. Here, we describe an approach to isolate and characterize REPs. We bred mice bearing an Epo gene allele to which green fluorescent protein (GFP) reporter cDNA was knocked-in (EpoGFP) with mice bearing an Epo gene allele lacking the 3β€² enhancer (EpoΞ”3β€²E). Mice harboring the mutant EpoGFP/Ξ”3β€²E gene exhibited anemia (average Hematocrit 18% at 4 to 6 days after birth), and this perinatal anemia enabled us to identify and purify REPs based on GFP expression from the kidney. Light and confocal microscopy revealed that GFP immunostaining was confined to fibroblastic cells that reside in the peritubular interstitial space, confirming our previous observation in Epo-GFP transgenic reporter assays. Flow cytometry analyses revealed that the GFP fraction constitutes approximately 0.2% of the whole kidney cells and 63% of GFP-positive cells co-express CD73 (a marker for cortical fibroblasts and Epo-expressing cells in the kidney). Quantitative RT-PCR analyses confirmed that Epo expression was increased by approximately 100-fold in the purified population of REPs compared with that of the unsorted cells or CD73-positive fraction. Gene expression analyses showed enrichment of Hif2Ξ± and Hif3Ξ± mRNA in the purified population of REPs. The genetic approach described here provides a means to isolate a pure population of REPs, allowing the analysis of gene expression of a defined population of cells essential for Epo production in the kidney. This has provided evidence that positive regulation by HIF2Ξ± and negative regulation by HIF3Ξ± might be necessary for correct renal Epo induction. (282 words

    Further Observations of the Tilted Planet XO-3: A New Determination of Spin-Orbit Misalignment, and Limits on Differential Rotation

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    Abstract: We report on observations of the Rossiter-McLaughlin (RM) effect for the XO-3 exoplanetary system. The RM effect for the system was previously measured by two different groups, but their results were statistically inconsistent. To obtain a decisive result we observed two full transits of XO-3b with the Subaru 8.2-m telescope. By modeling these data with a new and more accurate analytic formula for the RM effect, we find the projected spin-orbit angle to be Ξ»=37.3 deg Β± 3.0 deg, in good agreement with the previous finding by Winn et al. (2009). In addition, an offset of ~22 m/s[superscript -1] was observed between the two transit datasets. This offset could be a signal of a third body in the XO-3 system, a possibility that should be checked with future observations. We also attempt to search for a possible signature of the stellar differential rotation in the RM data for the first time, and put weak upper limits on the differential rotation parameters.United States. National Aeronautics and Space Administration (NNX11AG85G
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