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In Earth and planetary science, Pb isotopic composition is well known to play a key role in deciphering the origin and evolution of materials because they provide unique chronological and/or indigenous regional information as a radiogenic daughter nuclide from U and Th. To determine such an isotopic composition, mass spectrometers have been widely used over several decades, which requires a destructive/consuming treatment such as sputtering, laser ablation and thermal ionization. Here, we first report the non-destructive Pb isotopic measurement of natural galena (PbS) using the energy shift of muon-induced characteristic X-rays. The observed Pb isotopic composition of the natural galena is in good agreement with that obtained by conventional mass spectrometry. Such a muon-based Pb isotopic analysis method is expected to be applied to identify the production area of archaeological artefacts (e.g. bronze products), where non-destructive analysis is highly desirable compared to conventional mass spectrometry. [ABSTRACT FROM AUTHOR]

We report the discovery of a resolved (0.9 arcsec) substellar companion to a member of the 1–5 Myr Taurus star-forming region. The host star (2M0437) is a single mid-M type (T eff ≈ 3100 K) dwarf with a position, space motion, and colour–magnitude that support Taurus membership, and possible affiliation with a ∼2.5-Myr-old subgroup. A comparison with stellar models suggests a 2–5 Myr age and a mass of 0.15–0.18M⊙. Although K2 detected quasi-periodic dimming from close-in circumstellar dust, the star lacks detectable excess infrared emission from a circumstellar disc and its H α emission is not commensurate with accretion. Astrometry based on 3 yr of AO imaging shows that the companion (2M0437b) is comoving, while photometry of two other sources at larger separation indicates that they are likely heavily reddened background stars. A comparison of the luminosity of 2M0437b with models suggests a mass of 3–5 MJUP, well below the deuterium burning limit, and an effective temperature of 1400–1500 K, characteristic of a late L spectral type. The H − K colour is redder than the typical L dwarf, but comparable to other directly detected young planets, e.g. those around HR 8799. The discovery of a super-Jupiter around a very young, very low-mass star challenges models of planet formation by either core accretion (which requires time) or disc instability (which requires mass). We also detected a second, comoving, widely separated (75 arcsec) object that appears to be a heavily extincted star. This is certainly a fellow member of this Taurus subgroup and statistically likely to be a bound companion. [ABSTRACT FROM AUTHOR]

This study examined whether using an artificial neural network (ANN) helps beginners in diagnostic cardiac imaging to achieve similar results to experts when interpreting stress myocardial perfusion imaging (MPI). One hundred and thirty-eight patients underwent stress MPI with Tc-labeled agents. An expert and a beginner interpreted stress/rest MPI with or without the ANN and the results were compared. The myocardium was divided into 5 regions (the apex; septum; anterior; lateral, and inferior regions), and the defect score of myocardial blood flow was evaluated from 0 to 4, and SSS, SRS, and SDS were calculated. The ANN effect, defined as the difference in each of these scores between with and without the ANN, was calculated to investigate the influence of ANN on the interpreters' performance. We classified 2 groups (insignificant perfusion group and significant perfusion group) and compared them. In the same way, classified 2 groups (insignificant ischemia group and significant ischemia group) and compared them. Besides, we classified 2 groups (normal vessels group and multi-vessels group) and compared them. The ANN effect was smaller for the expert than for the beginner. Besides, the ANN effect for insignificant perfusion group, insignificant ischemia group and multi-vessels group were smaller for the expert than for the beginner. On the other hand, the ANN effect for significant perfusion group, significant ischemia group and normal vessels group were no significant. When interpreting MPI, beginners may achieve similar results to experts by using an ANN. Thus, interpreting MPI with ANN may be useful for beginners. Furthermore, when beginners interpret insignificant perfusion group, insignificant ischemia group and multi-vessel group, beginners may achieve similar results to experts by using an ANN. [ABSTRACT FROM AUTHOR]

M dwarf stars are high-priority targets for searches for Earth-size and potentially Earth-like planets, but their planetary systems may form and evolve in very different circumstellar environments than those of solar-type stars. To explore the evolution of these systems, we obtained transit spectroscopy and photometry of the Neptune-size planet orbiting the ≈650-Myr-old Hyades M dwarf K2-25. An analysis of the variation in spectral line shape induced by the Doppler 'shadow' of the planet indicates that the planet's orbit is closely aligned with the stellar equator (⁠|$\lambda =-1.7_{-3.7}^{+5.8}$| deg), and that an eccentric orbit found by previous work could arise from perturbations by another planet on a coplanar orbit. We detect no significant variation in the depth of the He i line at 1083 nm during transit. A model of atmospheric escape as an isothermal Parker wind with a solar composition shows that this non-detection is not constraining compared to escape rate predictions of ∼0.1 M⊕  Gyr−1; at such rates, at least several Gyr are required for a Neptune-like planet to evolve into a rocky super-Earth. [ABSTRACT FROM AUTHOR]

We obtained high-resolution infrared spectroscopy and short-cadence photometry of the 600–800 Myr Praesepe star K2-100 during transits of its 1.67-d planet. This Neptune-size object, discovered by the NASA K2 mission, is an interloper in the 'desert' of planets with similar radii on short-period orbits. Our observations can be used to understand its origin and evolution by constraining the orbital eccentricity by transit fitting, measuring the spin-orbit obliquity by the Rossiter–McLaughlin effect, and detecting any extended, escaping the hydrogen–helium envelope with the 10 830 -Å line of neutral helium in the 2s3S triplet state. Transit photometry with 1-min cadence was obtained by the K2 satellite during Campaign 18 and transit spectra were obtained with the IRD spectrograph on the Subaru telescope. While the elevated activity of K2-100 prevented us from detecting the Rossiter–McLaughlin effect, the new photometry combined with revised stellar parameters allowed us to constrain the eccentricity to e < 0.15/0.28 with 90/99 per cent confidence. We modelled atmospheric escape as an isothermal, spherically symmetric Parker wind, with photochemistry driven by ultraviolet radiation, which we estimate by combining the observed spectrum of the active Sun with calibrations from observations of K2-100 and similar young stars in the nearby Hyades cluster. Our non-detection (<5.7 m Å) of a transit-associated He  i line limits mass-loss of a solar-composition atmosphere through a T ≤ 10000 K wind to <0.3 M⊕ Gyr−1. Either K2-100b is an exceptional desert-dwelling planet, or its mass-loss is occurring at a lower rate over a longer interval, consistent with a core accretion-powered scenario for escape. [ABSTRACT FROM AUTHOR]

The biological behaviour and prognostic factors of Merkel cell carcinoma (MCC) in 20 cats were studied. The tumours were surgically removed and histopathologically examined. The animals were 8 to 20 years old (median age: 14 years), and the tumours were predominantly located in the neck and head. Follow‐up data were available in 17 cases, and 12 cats died within a year of surgery. The overall median survival time after resection was 243 days (range 16‐360 days). Recurrence occurred in 11 cases, although 6 of them (55%) were found to be margin‐negative. Possible metastasis occurred after the surgery in 10 cases, although 6 of them (60%) were found to be margin‐negative. The histopathological features of MCC included tumour necrosis in 16 cases (80%), vascular invasion in 6 cases (38%) and high mitotic counts (median: 28.5 per high‐power field). Irregular acanthosis was noted adjacent to the tumours in 9 cases (60%). Immunohistochemically, the tumour cells were positive for cytokeratin (CK) 20 and p63 in all cases, synaptophysin in 19 (95%) cases, and CK18 in 16 cases (80%). The study shows that feline MCC is associated with a poor prognosis and exhibited a strong tendency towards local recurrence, regional lymph node metastasis and distant spread. [ABSTRACT FROM AUTHOR]

Summary: An experiment was carried out to assess the feeding effect of Chinese herbal medicine on N balance, ruminal fermentation characteristics, kinetics of plasma glucose, leucine and energy metabolism in sheep kept at thermoneutral environment (23°C) or exposed to cold (2–4°C). Four sheep were subjected to either mixed hay (MH‐diet) or hay supplemented with 2% of a traditional nourishing Chinese herbal medicine mixture (Astragalus root, Angelica root and Atractylodes rhizome; CHM‐diet) over two 23‐day periods using a crossover design. Cold exposure was conducted for 5 days. The isotope dilution of [U‐13C]glucose with open circuit calorimetry was used to determine the turnover and oxidation rates of plasma glucose and metabolic heat production. The rate of plasma leucine turnover was measured with an isotope dilution method using [1‐13C]leucine. N intake was higher, N excretion through faeces was lower and N digestibility was higher for the CHM‐diet than the MH‐diet. Rumen pH was lower, concentration of rumen NH3 was higher, concentrations of rumen total VFA and acetate tended to be higher and propionate was higher for the CHM‐diet compared with the MH‐diet. Turnover rate of plasma glucose was higher for the CHM‐diet than the MH‐diet and increased during cold exposure. Oxidation rate of plasma glucose did not differ between diets and also between environments. Turnover rate of plasma leucine was higher for the CHM‐diet compared with the MH‐diet but remained similar between environments. Heat production was greater for the CHM‐diet than the MH‐diet and increased during cold exposure. No significant diet × environment interaction was detected. The present results demonstrated that plasma glucose and energy metabolism were enhanced by both Chinese herbal medicine and cold exposure; plasma leucine metabolism was enhanced by Chinese herbal medicine but with lack of change in response to cold exposure in sheep under the conditions of the current experiment. [ABSTRACT FROM AUTHOR]

Glycyrrhiza uralensis roots used in this study were produced using novel cultivation systems, including artificial hydroponics and artificial hydroponic-field hybrid cultivation. The equivalency between G. uralensis root extracts produced by hydroponics and/or hybrid cultivation and a commercial Glycyrrhiza crude drug were evaluated for both safety and efficacy, and there were no significant differences in terms of mutagenicity on the Ames tests. The levels of cadmium and mercury in both hydroponic roots and crude drugs were less than the limit of quantitation. Arsenic levels were lower in all hydroponic roots than in the crude drug, whereas mean lead levels in the crude drug were not significantly different from those in the hydroponically cultivated G. uralensis roots. Both hydroponic and hybrid-cultivated root extracts showed antiallergic activities against contact hypersensitivity that were similar to those of the crude drug extracts. These study results suggest that hydroponic and hybrid-cultivated roots are equivalent in safety and efficacy to those of commercial crude drugs. Further studies are necessary before the roots are applicable as replacements for the currently available commercial crude drugs produced from wild plant resources. [ABSTRACT FROM AUTHOR]

Vascular manifestations may dominate the clinical presentation in some Behçet's disease (BD) patients. We herein report the case of a patient with BD who developed an anastomotic pseudoaneurysm 21 years after surgical treatment of multiple arterial lesions, including an abdominal aortic aneurysm (AAA). (A) Intraoperative angiogram showing a pseudoaneurysm at the right common iliac artery; (B) completion angiogram showing successful exclusion of the pseudoaneurysm. [Extracted from the article]

Deals with a study which determined the magnetic and electrical properties of the amorphous iron-boron-oxygen thin film alloys. Background to the study; Methods and results; Discussion and conclusion.

Presents a study which examined the effect of nitrogen upon enhancement of the magnetic Kerr rotation in zinc sulfur(oxyge)/terbium iron cobalt bilayer films. Film preparation; Film characterization; Discussion and conclusions.

The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and serves as a testbed for high-contrast imaging technologies for ELTs. It is a multiband instrument which makes use of light from 600 to 2500 nm, allowing for coronagraphic direct exoplanet imaging of the inner 3λ/D from the stellar host. Wavefront sensing and control are key to the operation of SCExAO. A partial correction of low-order modes is provided by Subaru's facility adaptive optics system with the final correction, including high-order modes, implemented downstream by a combination of a visible pyramid wavefront sensor and a 2000-element deformable mirror. The well-corrected NIR (y-K bands) wavefronts can then be injected into any of the available coronagraphs, including but not limited to the phase-induced amplitude apodization and the vector vortex coronagraphs, both of which offer an inner working angle as low as 1λ/D. Noncommon path, low-order aberrations are sensed with a coronagraphic low-order wavefront sensor in the infrared (IR). Low noise, high frame rate NIR detectors allow for active speckle nulling and coherent differential imaging, while the HAWAII 2RG detector in the HiCIAO imager and/or the CHARIS integral field spectrograph (from mid-2016) can take deeper exposures and/or perform angular, spectral, and polarimetric differential imaging. Science in the visible is provided by two interferometric modules: VAMPIRES and FIRST, which enable subdiffraction limited imaging in the visible region with polarimetric and spectroscopic capabilities respectively. We describe the instrument in detail and present preliminary results both onsky and in the laboratory. [ABSTRACT FROM AUTHOR]

We present results from the first three years of observations of moving group (MG) targets in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) high-contrast imaging survey of exoplanets and disks using the Subaru telescope. We achieve typical contrasts of ∼105 at 1″ and ∼106 beyond 2″ around 63 proposed members of nearby kinematic MGs. We review each of the kinematic associations to which our targets belong, concluding that five, β Pictoris (∼20 Myr), AB Doradus (∼100 Myr), Columba (∼30 Myr), Tucana-Horogium (∼30 Myr), and TW Hydrae (∼10 Myr), are sufficiently well-defined to constrain the ages of individual targets. Somewhat less than half of our targets are high-probability members of one of these MGs. For all of our targets, we combine proposed MG membership with other age indicators where available, including Ca II HK emission, X-ray activity, and rotation period, to produce a posterior probability distribution of age. SEEDS observations discovered a substellar companion to one of our targets, κ And, a late B star. We do not detect any other substellar companions, but do find seven new close binary systems, of which one still needs to be confirmed. A detailed analysis of the statistics of this sample, and of the companion mass constraints given our age probability distributions and exoplanet cooling models, will be presented in a forthcoming paper. [ABSTRACT FROM AUTHOR]

Several exoplanets have recently been imaged at wide separations of >10 AU from their parent stars. These span a limited range of ages (<50 Myr) and atmospheric properties, with temperatures of 800-1800 K and very red colors (J -H > 0.5 mag), implying thick cloud covers. Furthermore, substantial model uncertainties exist at these young ages due to the unknown initial conditions at formation, which can lead to an order of magnitude of uncertainty in the modeled planet mass. Here, we report the direct-imaging discovery of a Jovian exoplanet around the Sun-like star GJ 504, detected as part of the SEEDS survey. The system is older than all other known directly imaged planets; as a result, its estimated mass remains in the planetary regime independent of uncertainties related to choices of initial conditions in the exoplanet modeling. Using the most common exoplanet cooling model, and given the system age of 160+350 Myr, GJ 504b has an estimated mass of 4+4.5 -1.0 Jupiter masses, among the lowest of directly imaged planets. Its projected separation of 43.5 AU exceeds the typical outer boundary of ~30 AU predicted for the core accretion mechanism. GJ 504b is also significantly cooler (510+30 -20 K) and has a bluer color (J - H = -0.23 mag) than previously imaged exoplanets, suggesting a largely cloud-free atmosphere accessible to spectroscopic characterization. Thus, it has the potential of providing novel insights into the origins of giant planets as well as their atmospheric properties. [ABSTRACT FROM AUTHOR]

Background:Pancreatic ductal carcinoma (PDC) is one of the most lethal human carcinomas. Expression patterns of some genes may predict gemcitabine (GEM) treatment efficacy. We examined predictive indicators of survival in GEM-treated patients by quantifying the expression of several genes in pre-treatment endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples from patients with PDC.Methods:The expressions of human equilibrative nucleoside transporter 1 (hENT1), deoxycitidine kinase, ribonucleoside reductase 1, ribonucleoside reductase 2 and Notch3 in EUS-FNA tissue samples from 71 patients with unresectable PDC were quantified using real-time reverse transcription-polymerase chain reactions and examined for correlations with GEM sensitivity.Results:The log-rank test detected no significant differences in overall survival between GEM-treated patients with low and high mRNA levels of all genes examined. However, low Notch3 mRNA expression was significantly associated with longer overall survival in a multivariate analysis for survival (P=0.0094). High hENT1 expression level was significantly associated with a longer time to progression (P=0.039). Interaction tests for GEM administration and hENT1 or Notch3 mRNA expression were statistically significant (P=0.0054 and 0.0047, respectively).Conclusion:hENT1 and Notch3 mRNA expressions in EUS-FNA specimens were the key predictive biomarkers of GEM effect and GEM sensitivity in patients with unresectable PDC. [ABSTRACT FROM AUTHOR]

Background and study aims: Endocytoscopy enables observation at 450-fold magnification during gastrointestinal endoscopy, allowing on-site "optical biopsy." We compared the accuracies of endocytoscopy and standard biopsy for the diagnosis of colorectal neoplasms. Patients and methods: We performed a randomized, controlled, open-label trial of patients with colorectal lesions (≥5mm) detected during colonoscopy in a tertiary referral center.We randomly assigned the 203 detected lesions of 170 eligible patients to either the endocytoscopy or standard biopsy group. An on-site endoscopist assessed the histopathology of the endocytoscopy group lesions according to the endocytoscopic findings, whereas a pathologist later assessed standard biopsy group lesions by microscopic examination of the biopsy specimens. We calculated the diagnostic accuracies in both groups with reference to the final histopathology of the resected specimens. The primary endpoint was to determine whether the diagnostic accuracy of endocytoscopy for neoplastic lesionswas noninferior to that of standard biopsy (with a predefined noninferiority margin of 10%). Analyses were by intention-to-treat and per-protocol. The study is registered, number UMIN000003923. Results: Overall, 102 lesions in the endocytoscopy group and 101 in the standard biopsy group were available for primary outcome analysis. There were no complications. The diagnostic accuracy of endocytoscopy for the discrimination of neoplastic lesions was 94.1% (95% confidence interval 87.6% to 97.8 %), whereas that of standard biopsy was 96.0% (90.2% to 98.9 %), which is within the noninferiority margin (absolute difference -1.9 %, -8.6% to +5.0 %). Conclusions: Endocytoscopy is noninferior to standard biopsy for the discrimination of neoplastic lesions. With its advantage of providing an on-site diagnosis, endocytoscopy could provide a novel alternative to standard biopsy in routine colonoscopy. [ABSTRACT FROM AUTHOR]