Searches for New Milky Way Satellites from the First Two Years of Data of the Subaru/Hyper Suprime-Cam Survey: Discovery of Cetus~III

We present the results from a search for new Milky Way (MW) satellites from the first two years of data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP) $\sim 300$~deg$^2$ and report the discovery of a highly compelling ultra-faint dwarf galaxy candidate in Cetus. This is the second ultra-faint dwarf we have discovered after Virgo~I reported in our previous paper. This satellite, Cetus~III, has been identified as a statistically significant (10.7$\sigma$) spatial overdensity of star-like objects, which are selected from a relevant isochrone filter designed for a metal-poor and old stellar population. This stellar system is located at a heliocentric distance of 251$^{+24}_{-11}$~kpc with a most likely absolute magnitude of $M_V = -2.4 \pm 0.6$~mag estimated from a Monte Carlo analysis. Cetus~III is extended with a half-light radius of $r_h = 90^{+42}_{-17}$~pc, suggesting that this is a faint dwarf satellite in the MW located beyond the detection limit of the Sloan Digital Sky Survey. Further spectroscopic studies are needed to assess the nature of this stellar system. We also revisit and update the parameters for Virgo~I finding $M_V = -0.33^{+0.75}_{-0.87}$~mag and $r_h = 47^{+19}_{-13}$~pc. Using simulations of $\Lambda$-dominated cold dark matter models, we predict that we should find one or two new MW satellites from $\sim 300$~deg$^2$ HSC-SSP data, in rough agreement with the discovery rate so far. The further survey and completion of HSC-SSP over $\sim 1,400$~deg$^2$ will provide robust insights into the missing satellites problem.Comment: 12 pages, 12 figures, accepted for publication in PASJ special issu

Bo\"otes IV: A New Milky Way Satellite Discovered in the Subaru Hyper Suprime-Cam Survey and Implications for the Missing Satellite Problem

We report on the discovery of a new Milky Way (MW) satellite in Bo\"otes based on data from the on-going Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). This satellite, named Bo\"otes IV, is the third ultra-faint dwarf that we have discovered in the HSC-SSP. We have identified a statistically significant (32.3$\sigma$) overdensity of stars having characteristics of a metal-poor, old stellar population. The distance to this stellar system is $D_{\odot}=209^{+20}_{-18}$ kpc with a $V$-band absolute magnitude of $M_V=-4.53^{+0.23}_{-0.21}$ mag. Bo\"otes IV has a half-light radius of $r_h=462^{+98}_{-84}$ pc and an ellipticity of $0.64^{+0.05}_{-0.05}$, which clearly suggests that this is a dwarf satellite galaxy. We also found another overdensity that appears to be a faint globular cluster with $M_V=-0.20^{+0.59}_{-0.83}$ mag and $r_h=5.9^{+1.5}_{-1.3}$ pc located at $D_{\odot}=46^{+4}_{-4}$ kpc. Adopting the recent prediction for the total population of satellites in a MW-sized halo by Newton et al. (2018), which combined the characteristics of the observed satellites by SDSS and DES with the subhalos obtained in $\Lambda$CDM models, we estimate that there should be about two MW satellites at $M_V\le0$ in the $\sim676$ deg$^2$ covered by HSC-SSP, whereas that area includes six satellites. Thus, the observed number of satellites is larger than the theoretical prediction. On the face of it, we have a problem of too many satellites, instead of the well-known missing satellites problem whereby the $\Lambda$CDM theory overpredicts the number of satellites in a MW-sized halo. This may imply that the models need more refinements for the assignment of subhalos to satellites such as considering those found by the current deeper survey. [abridged]Comment: 13 pages, 11 figures, 2 tables, accepted for publication in PAS

The Hyper Suprime-Cam SSP survey: Overview and survey design

Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2-m Subaru telescope on the summit of Mauna Kea in Hawaii. A team of scientists from Japan, Taiwan, and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg2 in five broad bands (grizy), with a 5 σ point-source depth of r ≈ 26. The Deep layer covers a total of 26 deg2 in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg2). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey

The Missing Satellite Problem Outside of the Local Group. I. Pilot Observation

We present results from a pilot observation of nearby (~20 Mpc) galaxies with masses similar to that of the Milky Way (MW) to address the missing satellite problem. This is the first paper from an ongoing project to address the problem with a statistical sample of galaxies outside of the Local Group (LG) without employing an assumption that the LG is a typical halo in the universe. Thanks to the close distances of our targets, dwarf galaxies around them can be identified as extended, diffuse galaxies. By applying a surface brightness cut together with a careful visual screening to remove artifacts and background contamination, we construct a sample of dwarf galaxies. The luminosity function (LF) of one of the targets is broadly consistent with that of the MW, but the other has a more abundant dwarf population. Numerical simulations by Okamoto seem to overpredict the number of dwarfs on average, while more recent predictions from Copernicus Complexio are in better agreement. In both observations and simulations, there is a large diversity in the LFs, demonstrating the importance of addressing the missing satellite problem with a statistically representative sample. We also characterize the projected spatial distributions of the satellites and do not observe strong evidence for alignments around the central galaxies. Based on this successful pilot observation, we are carrying out further observations to increase the sample of nearby galaxies, which we plan to report in our future paper

Pharmacokinetics of Gefitinib in a Patient with Non-Small Cell Lung Cancer Undergoing Continuous Ambulatory Peritoneal Dialysis

A 72-year-old man undergoing continuous ambulatory peritoneal dialysis (CAPD) for chronic renal failure and who had undergone right upper lobectomy for lung adenocarcinoma (pT2aN0M0) 2 years ago was admitted for recurrence of lung cancer presenting as multiple brain metastases. An epidermal growth factor receptor mutation analysis of his lung cancer revealed a deletion of 15 nucleotides (E746-A750) in exon 19. After whole-brain radiotherapy, we started daily administration of 250 mg gefitinib under the continuation of CAPD and performed a pharmacokinetic analysis. We speculated that the plasma concentration of gefitinib reached the steady state at least by day 16 after the start of gefitinib (626.6 ng/ml at trough level). On day 46, the plasma concentration was 538.4 ng/ml at trough level and the concentration in the peritoneal dialysis fluid was 34.6 ng/ml, suggesting that CAPD appeared to have little effect on the pharmacokinetics of gefitinib. During gefitinib therapy, there were no significant adverse events except for grade 2 diarrhea. Gefitinib could be safely administered to a patient undergoing CAPD

Gpr176 is a Gz-linked orphan G-protein-coupled receptor that sets the pace of circadian behaviour.

体内時計を調節するオーファンGPCRの同定 －生体リズム調整薬の開発に期待－. 京都大学プレスリリース. 2016-02-18.G-protein-coupled receptors (GPCRs) participate in a broad range of physiological functions. A priority for fundamental and clinical research, therefore, is to decipher the function of over 140 remaining orphan GPCRs. The suprachiasmatic nucleus (SCN), the brain's circadian pacemaker, governs daily rhythms in behaviour and physiology. Here we launch the SCN orphan GPCR project to (i) search for murine orphan GPCRs with enriched expression in the SCN, (ii) generate mutant animals deficient in candidate GPCRs, and (iii) analyse the impact on circadian rhythms. We thereby identify Gpr176 as an SCN-enriched orphan GPCR that sets the pace of circadian behaviour. Gpr176 is expressed in a circadian manner by SCN neurons, and molecular characterization reveals that it represses cAMP signalling in an agonist-independent manner. Gpr176 acts independently of, and in parallel to, the Vipr2 GPCR, not through the canonical Gi, but via the unique G-protein subclass Gz

Flow cytometric analysis of lymphocyte profiles in mediastinal lymphadenopathy of sarcoidosis.

Lymphocyte profiles in mediastinal lymph nodes may reflect the immune status of patients with sarcoidosis. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is useful for the diagnosis of diseases with mediastinal lymphadenopathy including sarcoidosis. The purpose of this study was to determine lymphocyte profiles of lymph nodes in sarcoidosis by analyzing EBUS-TBNA samples. We prepared single cell suspensions from EBUS-TBNA samples of mediastinal lymph nodes from patients with sarcoidosis or lung cancer and analyzed surface markers (CD3, CD4, CD8, CD19, CD25) and FoxP3 expression in the resultant lymphocytes using flow cytometry. We studied 26 patients with sarcoidosis and 16 with lung cancer with mediastinal lymph node metastases. In sarcoidosis, the CD4/CD8 ratio was significantly more elevated in lymph nodes than in bronchoalveolar lavage fluid (P<0.001), although both were strongly correlated. The CD4/CD8 ratio was significantly higher in stage I than in stage II both in the BAL fluid and lymph nodes. When compared with lung cancer lymph node metastasis, the CD4/CD8 ratio was significantly higher in sarcoidosis, whereas the CD3/CD19 ratio was significantly higher in lung cancer. The proportion of regulatory T cells (CD4+, CD25+, FoxP3 high) did not differ between sarcoidosis and lung cancer samples. Lymphocyte profiles in mediastinal lymphadenopathy can be analyzed by flow cytometry of EBUS-TBNA samples. These findings might help elucidate the immunopathology of sarcoidosis

A simple method of bronchial occlusion with silicone spigots (Endobronchial Watanabe Spigot; EWS) using a curette

Background: Bronchial occlusion with an Endobronchial Watanabe Spigot (EWS) has been shown to be useful in managing prolonged bronchopleural fistulas and intractable hemoptysis. EWS bronchial occlusion using a curette is less technically demanding. This retrospective study evaluated the clinical utility and simplicity of this method. Methods: A total of 18 consecutive patients (15 men, 3 women, aged 47–85 years) who underwent bronchial occlusion using an EWS from April 2012 to August 2014 were evaluated. The method involves sticking the tip of a curette into an EWS to the first joint, allowing it to be turned in any direction or at any angle. The time required to occlude the target bronchus was measured on routinely recorded digital videos. Other parameters evaluated included success rates, complications, and clinical outcomes. Results: Of the 18 patients, 11 underwent bronchial occlusion for intractable pneumothorax, 5 for postoperative bronchopleural fistula, two for intractable empyema, and one for hemoptysis. Each patient required 1–7 EWSs (median 4). Target bronchi included the right upper ( n = 8), left upper ( n = 5), right lower ( n = 2), left lower ( n = 2), and right middle ( n = 1) bronchi. The success rate of EWS insertion into the target bronchus was 100%. Time per EWS occlusion ranged from 65–528 sec (median 158.5 sec). Of the 62 insertions, 36 (58.1%) were completed within 3 min, and 58 (93.5%) within 5 min. Successful outcomes were observed in 15 (83.3%) of the 18 patients. Conclusions: EWS bronchial occlusion using a curette is a simple method for managing intractable bronchopleural fistulas in daily clinical settings