Search

The Laser Interferometer Gravitational-wave Observatory Scientific Collaboration and Virgo Collaboration (LVC) sent out 56 gravitational-wave (GW) notices during the third observing run (O3). Japanese collaboration for Gravitational wave ElectroMagnetic follow-up (J-GEM) performed optical and near-infrared observations to identify and observe an electromagnetic (EM) counterpart. We constructed web-based system which enabled us to obtain and share information of candidate host galaxies for the counterpart, and status of our observations. Candidate host galaxies were selected from the GLADE catalog with a weight based on the three-dimensional GW localization map provided by LVC. We conducted galaxy-targeted and wide-field blind surveys, real-time data analysis, and visual inspection of observed galaxies. We performed galaxy-targeted follow-ups to 23 GW events during O3, and the maximum probability covered by our observations reached to 9.8%. Among them, we successfully started observations for 10 GW events within 0.5 days after the detection. This result demonstrates that our follow-up observation has a potential to constrain EM radiation models for a merger of binary neutron stars at a distance of up to $\sim$100~Mpc with a probability area of $\leq$ 500~deg$^2$., 25 pages, 10 figures, 3 tables, published at https://academic.oup.com/ptep/article/2021/5/05A104/6122445

We are developing a high-resolution near-infrared spectrograph for exoplanet searches with telescopes in Suther- land, South Africa; the South Africa Near-infrared Doppler (SAND) instrument. It covers the z- and Y -bands (0.83–1.10 µm) simultaneously with a maximum spectral resolution of 55, 000. This specification enables the precise radial velocity (RV) measurements to search for both giant planets around young stars and habitable planets around nearby M-dwarfs. The SAND is a fiber-fed instrument and, therefore, can be installed into several telescopes at the same site by changing the fiber connection. It will be operated mainly on the PRIME telescope, which is newly developed by Osaka University in Japan. The InfraRed Survey Facility (IRSF) and the Southern African Large Telescope (SALT) are also candidate telescopes for the installation. Inside the SAND spectrograph, a star image ejected from the fiber is sliced half and each sliced image is spectrally dispersed by an echelle grating. As a reference source for the wavelength calibration, light transmitted from a Fabry-Perot Etalon is simultaneously injected into the spectrograph and share the almost identical optical pass. The SAND is expected to realize RV-measurements for targets in large stellar associations at the southern sky, with exclusive and flexible use of the telescope time.

Narrow-band filters can detect emission and absorption line features from multiple sources in a field of view simultaneously without spectroscopy. However, it is difficult to estimate and subtract the continuum component from sources of different spectral slope, especially when the equivalent width of the target lines is small. For example, Cataclysmic Variables have equivalent widths of hydrogen recombination emission lines of about –10 to –100 angstroms, but many of the ones that have been detected by conventional NB filters so far have a large equivalent width. We have therefore constructed novel narrow-band filters with transmission bands on both sides of the central wavelengths of the Paβ (1.282 µm) and Brγ (2.167 µm) emission lines so that we can evaluate the continuum level more accurately than the conventional filters having transmission in only one side of the target line. We installed the narrow-band filters to the Simultaneous three-color InfraRed Imager for Unbiased Survey (SIRIUS) in the InfraRed Survey Facility (IRSF) telescope at South African Astronomical Observatory (SAAO), and evaluated their performance. We found that the narrow-band filters can detect emission line features with an equivalent width of several tens of angstroms. Thus, this filter set is useful for detecting emission line features from targets with small equivalent widths that have been difficult to detect with the conventional NB filter set.

AP Lyn and V837 Her are long-period Mira variable stars in the Milky Way. We performed VLBI Exploration of Radio Astrometry (VERA) phase-referenced observations towards H2O masers associated with AP Lyn and V837 Her. The annual parallaxes of AP Lyn and V837 Her were obtained to be 2.008 ± 0.038 mas and 1.090 ± 0.014 mas, corresponding to distances of 498 ± 10 pc and 917 ± 12 pc, respectively. From our multi-epoch infrared observations using the Kagoshima University 1 m telescope, we derived the mean J-, H-, and K′-band magnitudes of AP Lyn, V837 Her, and an additional long-period Mira variable BX Cam, whose parallax is known. We derived their pulsation periods to be 433 ± 1 d, 520 ± 1 d, and 458 ± 1 d, respectively, using the K′-band light curves. The MK–log P relation of long-period Mira variables seem to be violated by Mira variable stars with larger-than-expected MK values (like OZ Gem) in the Milky Way because of circumstellar extinction leading to an observed dimming effect. AP Lyn, V837 Her, and BX Cam (like OZ Gem) are dimming from the trend to O-rich stars in the Large Magellanic Cloud. This implies that the high metallicity of the Milky Way galaxy increases the opacity of the Mira-type variable stars and strengthens mass loss.

OZ Geminorum (OZ Gem) is a galactic Mira variable in the Milky Way (MW). We measured its annual parallax with VLBI Exploration of Radio Astrometry to be π = 0.806 ± 0.039 mas, corresponding to a distance of D = 1.24 ± 0.06 kpc. Based on multi-epoch infrared observations with the Kagoshima University 1 m telescope, we also derived the mean J-, H-, and K′-band magnitudes of OZ Gem to be 5.75 ± 0.47 mag, 4.00 ± 0.16 mag, and 2.65 ± 0.16 mag, respectively. We derived a pulsation period of OZ Gem as 592 ± 1 d from the K′-band lightcurve. From the period–luminosity (P–L) relation and two-color diagram of the Large Magellanic Cloud (LMC), the property of OZ Gem suggests that OZ Gem is assigned among the carbon-rich Mira variables. However, our optical spectroscopic observational results (with the 1.5 m Kanata telescope) confirmed OZ Gem to be an oxygen-rich Mira star with the detection of multiple titanium oxide transition absorption lines. We suggest that OZ Gem is a low-mass star evolving to an OH/IR star with large mass loss and dust formation. It is predicted that the lower limit to the initial mass of AGB stars for developing the C-rich surface chemistry is larger in the MW than in the LMC because of larger metallicity, and OZ Gem is likely to be the first example to prove this. Our results highlight the necessity of deriving the PL relation of the Milky Way with high accuracy.

The magnetic field structure of a star-forming Bok globule BHR 71 was determined based on near-infrared polarimetric observations of background stars. The magnetic field in BHR 71 was mapped from 25 stars. By using a simple 2D parabolic function, the plane-of-sky magnetic axis of the core was found to be $\theta_{\rm mag} = 125^{\circ} \pm 11^{\circ}$. The plane-of-sky mean magnetic field strength of BHR 71 was found to be $B_{\rm pos} = 8.8 - 15.0$ $\mu$G, indicating that the BHR 71 core is magnetically supercritical with $\lambda = 1.44 - 2.43$. Taking into account the effect of thermal/turbulent pressure and the plane-of-sky magnetic field component, the critical mass of BHR 71 was $M_{\rm cr} = 14.5-18.7$ M$_{\odot}$, which is consistent with the observed core mass of $M_{\rm core} \approx 14.7$ M$_{\odot}$ (Yang et al. 2017). We conclude that BHR 71 is in a condition close to a kinematically critical state, and the magnetic field direction lies close to the plane of sky. Since BHR 71 is a star-forming core, a significantly subcritical condition (i.e., the magnetic field direction deviating from the plane of sky) is unlikely, and collapsed from a condition close to a kinematically critical state. There are two possible scenarios to explain the curved magnetic fields of BHR 71, one is an hourglass-like field structure due to mass accumulation and the other is the Inoue \& Fukui (2013) mechanism, which proposes the interaction of the core with a shock wave to create curved magnetic fields wrapping around the core., Comment: Accepted for publication in ApJ

This study was designed to evaluate the effects of DS37001789, a novel and highly potent urotensin II (U-II) receptor (GPR14) antagonist, against mortality, hypertrophy, and cardiac dysfunction in pressure-overload hypertrophy by transverse aortic constriction (TAC) in mice. In addition, we analyzed the phenotype of GPR14 knockout (KO) mice after TAC induction to confirm the contribution of the U-II/GPR14 system. The oral administration of 0.2% DS37001789 to TAC mice for 12 weeks significantly ameliorated the mortality rate and 0.2% DS37001789 for 4 weeks significantly improved cardiac function by pressure-volume analysis. GPR14 expression was significantly upregulated in the left ventricle in the TAC mice treated with 0.2% DS37001789. Moreover, we confirmed that the significant amelioration of mortality was accomplished by the inhibition of cardiac enlargement and the improvement of cardiac function in GPR14 KO mice after TAC surgery. These results suggest that the U-II/GPR14 system contributes to the progression of heart failure and its blockade ameliorates the mortality via improved cardiac function. The U-II/GPR14 system may thus be an attractive target for treating heart failure with pathological cardiac hypertrophy and DS37001789 may be a novel therapeutic agent for heart failure in patients with pressure-overload conditions such as hypertension and aortic valve stenosis., Urotensin II; GPR14; Heart failure; Transverse aortic constriction; Biological sciences; Endocrinology; Diabetes; Health sciences; Cardiology; Cardiovascular system; Renal system; Pharmaceutical science; Biochemistry; Medicine; Physiology.

In this study, the detailed magnetic field structure of the dense protostellar core Barnard 335 (B335) was revealed based on near-infrared polarimetric observations of background stars to measure dichroically polarized light produced by magnetically aligned dust grains in the core. Magnetic fields pervading B335 were mapped using 24 stars after subtracting unrelated ambient polarization components, for the first time revealing that they have an axisymmetrically distorted hourglass-shaped structure toward the protostellar core. On the basis of simple two- and three-dimensional magnetic field modeling, magnetic inclination angles in the plane-of-sky and line-of-sight directions were determined to be $90^{\circ} \pm 7^{\circ}$ and $50^{\circ} \pm 10^{\circ}$, respectively. The total magnetic field strength of B335 was determined to be $30.2 \pm 17.7$ $\mu {\rm G}$. The critical mass of B335, evaluated using both magnetic and thermal/turbulent support against collapse, was determined to be $M_{\rm cr} = 3.37 \pm 0.94$ ${\rm M}_{\odot}$, which is identical to the observed core mass of $M_{\rm core}=3.67$ M$_{\odot}$. We thus concluded that B335 started its contraction from a condition near equilibrium. We found a linear relationship in the polarization versus extinction diagram, up to $A_V \sim 15$ mag toward the stars with the greatest obscuration, which verified that our observations and analysis provide an accurate depiction of the core., Comment: Accepted for publication in ApJ. arXiv admin note: substantial text overlap with arXiv:1910.09121, arXiv:1912.10029

The goal of this paper is to characterise the light variation properties of Mira variables in the Small Magellanic Cloud. We have investigated a combined optical and near infrared multi-epoch dataset of Mira variables based on our monitoring data obtained over 15 years. Bolometric correction relations are formulated for various near-infrared colours. We find that the same bolometric correction equation holds for both the bolometricly brightest and faintest pulsation phases. Period-bolometric magnitude relations and period-colour relations were derived using time-averaged values. Phase lags between bolometric phase and optical and near-infrared phases were detected from the O-rich (the surface C/O number ratio is below unity) Mira variables, while no significant systematic lags were observed in most of the C-rich (the C/O ratio is over unity) ones. Some Miras show colour phase inversions, e.g., $H-K_{\rm s}$ at its bluest while $J-H$ and $J-K_{\rm s}$ are at their reddest values at about the bolometricly brightest phase. Their occurrence conditions were studied but no clear direct or indirect trigger was found. A large NIR colour change unassociated with stellar pulsation was observed in Miras with long secondary periods, and its possible explanation is described., Comment: 20 pages, 22 figures, accepted for publication in MNRAS

This study investigates the influence of the condensation coefficient of vapour on the collapse of a bubble composed of condensable gas (vapour) and non-condensable gas (NC gas). We simulated vapour and NC gas flow inside a bubble based on the molecular gas dynamics analysis in order to replicate the phase change (viz., evaporation and condensation) precisely, by changing the initial number density ratio of the NC gas and vapour, the initial bubble radius and the value of the condensation coefficient. The results show that the motion of the bubble is unaffected by the value of the condensation coefficient when that value is larger than approximately 0.4. We also discuss NC gas drift at the bubble wall during the final stage of the bubble collapse and its influence on the condensation coefficient. We conclude that vapour molecules can behave as NC gas molecules when the bubble collapses, owing to the large concentration of NC gas molecules at the gas–liquid interface. That is, the condensation coefficient reaches almost zero when the bubble collapses violently.

Observational data for the hourglass-like magnetic field toward the starless dense core FeSt 1-457 were compared with a flux freezing magnetic field model (Myers et al. 2018). Fitting of the observed plane-of-sky magnetic field using the flux freezing model gave a residual angle dispersion comparable with the results based on a simple three-dimensional parabolic model. The best-fit parameters for the flux freezing model were a line-of-sight magnetic inclination angle of $\gamma_{\rm mag} = 35^{\circ} \pm 15^{\circ}$ and a core center to ambient (background) density contrast of $\rho_{\rm c} / \rho_{\rm bkg} = 75$. The initial density for core formation ($\rho_0$) was estimated to be $\rho_{\rm c} / 75 = 4670$ cm$^{-3}$, which is about one order of magnitude higher than the expected density ($\sim 300$ cm$^{-3}$) for the inter-clump medium of the Pipe Nebula. FeSt 1-457 is likely to have been formed from the accumulation of relatively dense gas, and the relatively dense background column density of $A_V \simeq 5$ mag supports this scenario. The initial radius (core formation radius) $R_0$ and the initial magnetic field strength $B_0$ were obtained to be 0.15 pc ($1.64 R$) and $10.8-14.6$ $\mu$G, respectively. We found that the initial density $\rho_0$ is consistent with the mean density of the nearly critical magnetized filament with magnetic field strength $B_0$ and radius $R_0$. The relatively dense initial condition for core formation can be naturally understood if the origin of the core is the fragmentation of magnetized filaments., Comment: Accepted for publication in ApJ

Heart failure often presents with prognosis-relevant impaired renal function. To investigate whether the chronic activation of guanylate cyclase-A (GC-A) protects both heart and kidney, we examined the effects of TDT, a neprilysin (NEP)-resistant natriuretic peptide (NP) derivative, on cardiac and renal dysfunction in Dahl salt-sensitive hypertensive (DS) rats. Pretreatment with NEP or NEP inhibitor did not influence GC-A activation by TDT both in vitro and in vivo, resulting in a long-acting profile of TDT compared with native human atrial NP (hANP). The repeated administration of TDT to DS rats suppressed the progress of cardiac hypertrophy, systolic/diastolic dysfunction, and proteinuria in a dose-dependent manner. Compared with vehicle and hANP, salt diet-induced podocyte injury was reduced by TDT, as analyzed by urinary podocalyxin concentration, renal expression of nephrin mRNA, and glomerular expression of desmin protein. Since glomerular TRPC6 plays detrimental roles in podocyte homeostasis, we examined the renal expression of TRPC6 in DS rats and found that salt diet upregulated the expression of TRPC6. Importantly, TRPC6 induction was significantly decreased in TDT-treated rats, compared with vehicle and hANP. Consistently, in primary-culture podocytes from DS rats, TDT inhibited ATP-induced calcium influx, similar to TRPC inhibitor SKF96365. Finally, TDT-mediated protection of podocytes was abolished by protein kinase G inhibitor KT5823. In conclusion, TDT treatment attenuated heart and kidney dysfunction, accompanied by podocyte protection through inhibition of TRPC6. Thus, long-acting NPs could be a new avenue for treatment of heart failure.

It has been elucidated that mineralocorticoid receptor antagonists reduce mortality in patients with congestive heart failure and post-acute myocardial infarction. A direct inhibition of aldosterone synthase (CYP11B2) is also expected to have therapeutic benefits equal in quality to mineralocorticoid receptor antagonists in terms of reducing mineralocorticoid receptor signaling. Therefore, we have screened our chemical libraries and identified a novel and potent aldosterone synthase inhibitor, 2,2,2-trifluoro-1-{4-[(4-fluorophenyl)amino]pyrimidin-5-y}-1-[1-(methylsulfonyl)piperidin-4-yl]ethanol (compound 1), by lead optimization. Pharmacological properties of compound 1 were examined in in vitro cell-based assays and an in vivo mouse model of pressure-overload hypertrophy by transverse aortic constriction (TAC). Compound 1 showed potent CYP11B2 inhibition against human and mouse enzymes (IC50; 0.003μM and 0.096μM, respectively) in a cell-based assay. The oral administration of 0.06% compound 1 in the food mixture of a mouse TAC model significantly reduced the plasma aldosterone level and ameliorated mortality rate. This study is the first to demonstrate that a CYP11B2 inhibitor improved survival rates of heart failure induced by pressure-overload in mice. The treatment of 0.06% compound 1 did not elevate plasma potassium level in this model, although further evaluation of hyperkalemia is needed. These results suggest that compound 1 can be developed as a promising oral CYP11B2 inhibitor for pharmaceutical applications. Compound 1 could also be a useful compound for clarifying the role of aldosterone in cardiac hypertrophy.

The magnetic field structure, kinematical stability, and evolutionary status of the starless dense core Barnard 68 (B68) are revealed based on the near-infrared polarimetric observations of background stars, measuring the dichroically polarized light produced by aligned dust grains in the core. After subtracting unrelated ambient polarization components, the magnetic fields pervading B68 are mapped using 38 stars and axisymmetrically distorted hourglass-like magnetic fields are obtained, although the evidence for the hourglass field is not very strong. On the basis of simple 2D and 3D magnetic field modeling, the magnetic inclination angles on the plane-of-sky and in the line-of-sight direction are determined to be $47^{\circ} \pm 5^{\circ}$ and $20^{\circ} \pm 10^{\circ}$, respectively. The total magnetic field strength of B68 is obtained to be $26.1 \pm 8.7$ $\mu {\rm G}$. The critical mass of B68, evaluated using both magnetic and thermal/turbulent support, is $M_{\rm cr} = 2.30 \pm 0.20$ ${\rm M}_{\odot}$, which is consistent with the observed core mass of $M_{\rm core}=2.1$ M$_{\odot}$, suggesting nearly critical state. We found a relatively linear relationship between polarization and extinction up to $A_V \sim 30$ mag toward the stars with deepest obscuration. Further theoretical and observational studies are required to explain the dust alignment in cold and dense regions in the core., Comment: Accepted by PASJ

We conducted near-infrared (JHKs) imaging polarimetry toward the infrared dark cloud (IRDC) M17 SWex, including almost all of the IRDC filaments as well as its outskirts, with the polarimeter SIRPOL on the IRSF 1.4 m telescope. We revealed the magnetic fields of M17 SWex with our polarization-detected sources that were selected by some criteria based on their near-IR colors and the column densities toward them, which were derived from the Herschel data. The selected sources indicate not only that the ordered magnetic field is perpendicular to the cloud elongation as a whole, but also that at both ends of the elongated cloud the magnetic field appears to bent toward its central part, i.e., large-scale hourglass-shaped magnetic field perpendicular to the cloud elongation. In addition to this general trend, the elongations of the filamentary subregions within the dense parts of the cloud appear to be mostly perpendicular to their local magnetic fields, while the magnetic fields of the outskirts appear to follow the thin filaments that protrude from the dense parts. The magnetic strengths were estimated to be ~70-300 microG in the subregions, of which lengths and average number densities are ~3-9 pc and ~2-7x10^3 cm^{-3}, respectively, by the Davis-Chandrasekhar-Fermi method with the angular dispersion of our polarization data and the velocity dispersion derived from the C^{18}O (J=1-0) data obtained by the Nobeyama 45 m telescope. These field configurations and our magnetic stability analysis of the subregions imply that the magnetic field have controlled the formation/evolution of the M17 SWex cloud., Comment: 16 pages, 13 figures, accepted in PASJ

This study was designed to characterize the pharmacological profile of DS37001789, which is a structurally novel piperazine derivative that acts as urotensin II (U-II) receptor antagonist. DS37001789 inhibited [I]-U-II binding to human GPR14, U-II receptor, with an IC50 value 0.9 nM. Its potency was superior to that of ACT-058362, a nonpeptide U-II receptor antagonist whose IC50 was 120 nM. Human U-II-induced vascular contraction was blocked by DS37001789. The dose-response curve of DS37001789 in rats and monkeys did not show species differences, and it shifted to the right without any effects on the maximum vascular response. Moreover, orally administered DS37001789 dose-dependently prevented human U-II-induced blood pressure elevation in mice, and this effect was significant at dose and higher dose (30 and 100 mg/kg), and its potency was superior to that of ACT-058362 (100 mg/kg). These results suggest that DS37001789 is a highly potent U-II receptor antagonist both in vitro and in vivo, with no marked species difference. DS37001789 would be a useful tool to clarify the physiological roles of U-II/GPR14 system. In addition, it can serve as a novel therapeutic agent for diseases in which the U-II/GPR14 system is upregulated, such as hypertension, heart failure, renal dysfunction, and diabetes.

The RCW 106 molecular cloud complex is an active massive star-forming region where a ministarburst is taking place. We examined its magnetic structure by near-IR polarimetric observations with the imaging polarimeter SIRPOL on the IRSF 1.4 m telescope. The global magnetic field is nearly parallel to the direction of the Galactic plane and the cloud elongation. We derived the magnetic field strength of $\sim100$-$1600~\mu$G for 71 clumps with the Davis-Chandrasekhar-Fermi method. We also evaluated the magnetic stability of these clumps and found massive star-forming clumps tend to be magnetically unstable and gravitationally unstable. Therefore, we propose a new criterion to search for massive star-forming clumps. These details suggest that the process enhancing the clump density without an increase of the magnetic flux is essential for the formation of massive stars and the necessity for accreting mass along the magnetic field lines., Comment: 14 pages, 4 figures, accepted to ApJL

The performance of a robot can be enhanced by increasing its output. However, increasing the output of rigid actuators such as motors and hydraulic actuators will likely increase the weight of the robot. Conversely, organisms such as human beings achieve high output within a short time by accumulating and releasing the elastic energy stored in their muscles; thus, providing an instantaneous force. Moreover, the viscoelastic properties of muscle enable organisms to control their instantaneous force outputs and overall movements. Therefore, in this study, we developed a manipulator with two-degree-of-freedom (DOF) variable viscoelastic joints. The manipulator comprised straight-fiber-type artificial muscles and a magnetorheological (MR) brakes. The ability of a manipulator to generate controlled movement from an instantaneous force was tested in a throwing operation. This simple two-DOF variable viscoelastic manipulator with apparent viscosity control by the MR brakes achieved successful throwing mo...

Recent large-scale infrared surveys have been revealing stellar populations in the inner Galaxy seen through strong interstellar extinction in the disk. In particular, classical Cepheids with their period-luminosity and period-age relations are useful tracers of Galactic structure and evolution. Interesting groups of Cepheids reported recently include four Cepheids in the Nuclear Stellar Disk (NSD), about 200 pc around the Galactic Centre, found by Matsunaga et al. and those spread across the inner part of the disk reported by Dekany and collaborators. We here report our discovery of nearly thirty classical Cepheids towards the bulge region, some of which are common with Dekany et al., and discuss the large impact of the reddening correction on distance estimates for these objects. Assuming that the four Cepheids in the NSD are located at the distance of the Galactic Centre and that the near-infrared extinction law, i.e. wavelength dependency of the interstellar extinction, is not systematically different between the NSD and other bulge lines-of-sight, most of the other Cepheids presented here are located significantly further than the Galactic Centre. This suggests a lack of Cepheids in the inner 2.5 kpc region of the Galactic disk except the NSD. Recent radio observations show a similar distribution of star-forming regions., 8 pages, 4 figures, accepted for publication in MNRAS

Urotensin II (U-II) has been found to be one of the most potent vasoconstrictor (Ames et al., 1999; Bohm et al., 2002) reported till date. U-II exerts its response via activation of a G-protein coupled receptor, Urotensin II receptor(UT). Binding of U-II to UT leads to an instant increase in the inositol phosphate turnover and intracellular Ca2+. Such an instant Ca2+ release and potent vasoconstriction exerted by U-II is expected to have an important role in the progression of cardiac diseases. We have previously shown that UT antagonist DS37001789 prevents U-II induced blood pressure elevation in mice (Nishi et al., 2019) in a dose dependent manner, with potent efficacy at 30 and 100 mg/kg. Further to this, we have also shown that DS37001789 ameliorates mortality in pressure-overload mice with heart failure (Nishi et al., 2020). We therefore conducted an extensive structure-activity relationship studies to identify molecules with superior efficacy. In the present manuscript, we report the identification of two potent, non-peptide small molecule antagonists of Urotensin II receptor (UT), RCI-0879 and RCI-0298 which blocked the action of U-II, both in vitro and in vivo. These molecules were found to be very potent in in vitro Ca2+ and radioligand binding assays using human and mouse UT over-expressing CHO cells. RCI-0879 and RCI-0298 also exhibited superior efficacy in in vivo mouse pressor response model using C57BL/6 mice, compared to our initial molecules (Nishi et al., 2019) and demonstrated ED50 values of 3.2 mg/kg and 6.8 mg/kg respectively. Our findings reported herewith, further strengthen our concept and belief in UT antagonization as a potential therapeutic approach for the management of chronic heart failure.

Detailed magnetic field structure of the dense core SL42 (CrA-E) in the Corona Australis molecular cloud complex was investigated based on near-infrared polarimetric observations of background stars to measure dichroically polarized light produced by magnetically aligned dust grains. The magnetic fields in and around SL42 were mapped using 206 stars and curved magnetic fields were identified. On the basis of simple hourglass (parabolic) magnetic field modeling, the magnetic axis of the core on the plane of sky was estimated to be $40^{\circ} \pm 3^{\circ}$. The plane-of-sky magnetic field strength of SL42 was found to be $22.4 \pm 13.9$ $��$G. Taking into account the effects of thermal/turbulent pressure and the plane-of-sky magnetic field component, the critical mass of SL42 was obtained to be $M_{\rm cr} = 21.2 \pm 6.6$ M$_{\odot}$, which is close to the observed core mass of $M_{\rm core} \approx 20$ M$_{\odot}$. We thus conclude that SL42 is in a condition close to the critical state if the magnetic fields lie near the plane of the sky. Since there is a very low luminosity object (VeLLO) toward the center of SL42, it is unlikely this core is in a highly subcritical condition (i.e., magnetic inclination angle significantly deviated from the plane of sky). The core probably started to collapse from a nearly kinematically critical state. In addition to the hourglass magnetic field modeling, the Inoue \& Fukui (2013) mechanism may explain the origin of the curved magnetic fields in the SL42 region., 23 pages, 12 figures, accepted for publication in ApJ. arXiv admin note: text overlap with arXiv:1912.10029

We investigate properties of the interstellar medium (ISM) interacting with shocks around the Galactic supernova remnant IC443, using the results of near-infrared [FeII] and H2 line mapping with the IRSF/SIRIUS. In the present study, we newly performed H2 1-0 S(1) and 2-1 S(1) line mapping with the narrow-band filters tuned for these lines, covering the entire remnant (30'x35'). Combined with an [FeII] line map, our result shows that the H2 line emission is significantly detected in the southern region, while the [FeII] line emission is detected all over the remnant, suggesting that slow and fast shocks propagate through the southern region and the entire remnant, respectively. In particular, the H2 line emission is relatively strong compared to the [FeII] line emission in the southwestern region, where TeV gamma-ray emission is detected. As the strong H2 line emission indicates the dominance of the dense ISM, this result supports the scenario that the gamma-ray emission is likely to be produced through a heavy interaction between cosmic-ray protons and the dense ISM in the southwestern shell. We also find that the H2 and [FeII] line emissions show an anti-correlated spatial distribution in the same region, suggesting the presence of the clumpy ISM. Such a clumpy morphology of the ISM around IC443 may assist cosmic-ray protons to efficiently interact with large amounts of the ISM protons., Comment: 20 pages, 6 figures, accepted for publication in ApJ

On 15 February 2013, the asteroid 367943 Duende (2012 DA14) experienced a near-Earth encounter at an altitude of 27,700 km or 4.2 Earth radii. We present here the results of an extensive, multi-observatory campaign designed to probe for spectral and/or rotational changes to Duende due to gravitational interactions with the Earth during the flyby. Our spectral data reveal no changes within the systematic uncertainties of the data. Post-flyby lightcurve photometry places strong constraints on the rotation state of Duende, showing that it is in non-principal axis rotation with fundamental periods of P_1 = 8.71 +/- 0.03 and P_2 = 23.7 +/- 0.2 hours. Multiple lightcurve analysis techniques, coupled with theoretical considerations and delay-doppler radar imaging, allows us to assign these periods to specific rotational axes of the body. In particular we suggest that Duende is now in a non-principal, short axis mode rotation state with a precessional period equal to P_1 and oscillation about the symmetry axis at a rate equal to P_2. Temporal and signal-to-noise limitations inherent to the pre-flyby photometric dataset make it difficult to definitively diagnose whether these periods represent a change imparted due to gravitational torques during the flyby. However, based on multiple analysis techniques and a number of plausibility arguments, we suggest that Duende experienced a rotational change during the planetary encounter with an increase in its precessional rotation period. Our preferred interpretation of the available data is that the precession rate increased from 8.4 hours prior to the flyby to 8.7 hours afterwards. A companion paper by Benson et al. (2019) provides a more detailed dynamical analysis of this event and compares the data to synthetic lightcurves computed from a simple shape model of Duende. (abbreviated abstract), Comment: 50 pages (double spaced), 12 figures, 5 tables, accepted to Icarus

The detailed magnetic field structure of the starless dense core CB81 (L1774, Pipe 42) in the Pipe Nebula was determined based on near-infrared polarimetric observations of background stars to measure dichroically polarized light produced by magnetically aligned dust grains in the core. The magnetic fields pervading CB81 were mapped using 147 stars and axisymmetrically distorted hourglass-like fields were identified. On the basis of simple 2D and 3D magnetic field modeling, the magnetic inclination angles in the plane-of-sky and line-of-sight directions were determined to be $4^{\circ} \pm 8^{\circ}$ and $20^{\circ} \pm 20^{\circ}$, respectively. The total magnetic field strength of CB81 was found to be $7.2 \pm 2.3$ $\mu{\rm G}$. Taking into account the effects of thermal/turbulent pressure and magnetic fields, the critical mass of CB81 was calculated to be $M_{\rm cr}=4.03 \pm 0.40$ M$_{\odot}$, which is close to the observed core mass of $M_{\rm core}=3.37 \pm 0.51$ M$_{\odot}$. We thus conclude that CB81 is in a condition close to the critical state. In addition, a spatial offset of $92''$ was found between the center of magnetic field geometry and the dust extinction distribution; this offset structure could not have been produced by self-gravity. The data also indicate a linear relationship between polarization and extinction up to $A_V \sim 30$ mag going toward the core center. This result confirms that near-infrared polarization can accurately trace the overall magnetic field structure of the core., Comment: Accepted for publication in ApJ. arXiv admin note: text overlap with arXiv:1910.09121

Many studies have shown that there are clear sequences in the period-luminosity relationship (PLR) for Mira variables and semiregular variables (SRVs) in the Large Magellanic Cloud (LMC). To investigate the PLR for SRVs in our galaxy, we examined the annual parallax measurement and conducted K'-band photometric monitoring of an SRV star SV Pegasus (SV Peg). We measured the position change of the associating H$_2$O maser spots by phase-referencing VLBI observations with VERA at 22 GHz, spanning approximately 3 yr, and detected an annual parallax of $\pi = 3.00 \pm 0.06$ mas, corresponding to a distance of $D=333 \pm 7$ pc. This result is in good agreement with the Hipparcos parallax and improves the accuracy of the distance from 35 $\%$ to 2 $\%$. However, the GAIA DR2 catalog gave a parallax of $\pi=1.12\pm0.28$ mas for SV Peg. This indicates that the GAIA result might be blurred by the effect of the stellar size because the estimated stellar radius was $\sim 5$ mas, which is comparable to the parallax. We obtained a K'-band mean magnitude of $m_{K'} = -0.48$ mag and a period of $P=177$ days from our photometric monitoring with a 1-m telescope. Using the trigonometric distance, we derived an absolute magnitude of $M_{K'}=-8.09 \pm 0.05$ mag. This result shows that the position of SV Peg in the PLR falls on the C' sequence found in the PLR in the LMC, which is similar to other SRVs in our galaxy., Comment: 19 pages, 10 figures. Accepted for publication in PASJ

A very long term near-infrared variable star survey towards the Large and Small Magellanic Clouds was carried out using the 1.4m InfraRed Survey Facility at the South African Astronomical Observatory. This project was initiated in December 2000 in the LMC, and in July 2001 in the SMC. Since then an area of 3 square degrees along the bar in the LMC and an area of 1 square degree in the central part of the SMC have been repeatedly observed. This survey is ongoing, but results obtained with data taken until December 2017 are reported in this paper. Over more than 15 years we have observed the two survey areas more than one hundred times. This is the first survey that provides near-infrared time-series data with such a long time baseline and on such a large scale. This paper describes the observations in the SMC and publishes a point source photometric catalogue, a variable source catalogue, and time-series data., Comment: 16 pages, 11 figures, accepted for publication in MNRAS

Atrial natriuretic peptide (ANP) exerts beneficial pharmacological effects in the treatment of various cardiovascular disorders, such as acute congestive heart failure (ADHF). However, the clinical use of ANP is limited to the continuous intravenous infusion owing to its short half-life (2.4 ± 0.7 min). In the present study, we conjugated the glyco-modified ANP with a monoclonal antibody (mAb) or an Fc via chemo-enzymatic glyco-engineering using EndoS D233Q/Q303L. The most potent derivative SG-ANP-Fc conjugate extended the half-life to 14.9 d and the duration of blood pressure lowering effect to over 28 d. This new biologic modality provides an opportunity to develop outpatient therapy after ADHF.

The relationship between dust polarization and extinction was determined for the cold dense starless molecular cloud core FeSt 1-457 based on the background star polarimetry of dichroic extinction at near-infrared wavelengths. Owing to the known (three-dimensional) magnetic field structure, the observed polarizations from the core were corrected by considering (a) the subtraction of the ambient polarization component, (b) the depolarization effect of inclined distorted magnetic fields, and (c) the magnetic inclination angle of the core. After these corrections, a linear relationship between polarization and extinction was obtained for the core in the range up to $A_V \approx 20$ mag. The initial polarization vs. extinction diagram changed dramatically after the corrections of (a) to (c), with the correlation coefficient being refined from 0.71 to 0.79. These corrections should affect the theoretical interpretation of the observational data. The slope of the finally obtained polarization--extinction relationship is $P_H / E_{H-K_s} = 11.00 \pm 0.72$ $\%$ ${\rm mag}^{-1}$, which is close to the statistically estimated upper limit of the interstellar polarization efficiency (Jones 1989). This consistency suggests that the upper limit of interstellar polarization efficiency might be determined by the observational viewing angle toward polarized astronomical objects., Accepted to the Astrophysical Journal (ApJ)

We present optical and near-infrared observations of a low-luminosity Type IIP supernova (SN) 2016bkv from the initial rising phase to the plateau phase. Our observations show that the end of the plateau is extended to $\gtrsim 140$ days since the explosion, indicating that this SN takes one of the longest time to finish the plateau phase. among Type IIP SNe (SNe IIP), including low-luminosity (LL) SNe IIP. The line velocities of various ions at the middle of the plateau phase are as low as 1,000--1,500 km s$^{-1}$, which is the lowest even among LL SNe IIP. These measurements imply that the ejecta mass in SN 2016bkv is larger than that of the well-studied LL IIP SN 2003Z. In the early phase, SN 2016bkv shows a strong bump in the light curve. In addition, the optical spectra in this bump phase exhibit a blue continuum accompanied with a narrow H$\alpha$ emission line. These features indicate an interaction between the SN ejecta and the circumstellar matter (CSM) as in SNe IIn. Assuming the ejecta-CSM interaction scenario, the mass loss rate is estimated to be $\sim 1.7 \times 10^{-2} M_{\odot}$ yr$^{-1}$ within a few years before the SN explosion. This is comparable to or even larger than the largest mass loss rate observed for the Galactic red supergiants ($\sim 10^{-3} M_{\odot}$ yr$^{-1}$ for VY CMa). We suggest that the progenitor star of SN 2016bkv experienced a violent mass loss just before the SN explosion., Comment: 9 pages, 12 figures. Accepted for publication in ApJ

We investigate the optical properties of Ophiuchus to obtain clues on the formation epoch of this cluster, and compare them to those of the Coma cluster, which is comparable in mass to Ophiuchus but much more disturbed dynamically. Based on a deep image of the Ophiuchus cluster in the r' band obtained at the Canada France Hawaii Telescope with the MegaCam camera, we have applied an iterative process to subtract the contribution of the numerous stars that pollute the image, due to the low Galactic latitude of the cluster, and obtained a photometric catalogue of 2818 galaxies fully complete at r'=20.5 mag and still 91% complete at r'=21.5 mag. We use this catalogue to derive the cluster Galaxy Luminosity Function (GLF) for the overall image and for a region (hereafter the "rectangle" region) covering exactly the same physical size as the region in which the GLF of the Coma cluster was studied by Adami et al. (2007). We then compute density maps based on an adaptive kernel technique, for different magnitude limits, and define three circular regions covering 0.08, 0.08 and 0.06 deg^2 respectively centered on the cluster (C), northwest (NW) and southeast (SE) of the cluster, in which we compute the GLFs. The GLF fits are much better when a Gaussian is added to the usual Schechter function, to account for the excess of very bright galaxies. Compared to Coma, Ophiuchus shows a strong excess of bright galaxies. The properties of the two nearby very massive clusters Ophiuchus and Coma are quite comparable, though they seem embedded in different large scale environments. Our interpretation is that Ophiuchus has built up long ago, as confirmed by its relaxed state (see paper I) while Coma is still in the process of forming., Accepted for publication in Astronomy & Astrophysics

In the present study, the magnetic field scaling on density, $|B| \propto \rho^{\kappa}$, was revealed in a single starless core for the first time. The $\kappa$ index of $0.78 \pm 0.10$ was obtained toward the starless dense core FeSt 1-457 based on the analysis of the radial distribution of the polarization angle dispersion of background stars measured at the near-infrared wavelengths. The result prefers $\kappa = 2/3$ for the case of isotropic contraction, and the difference of the observed value from $\kappa = 1/2$ is 2.8 sigma. The distribution of the ratio of mass to magnetic flux was evaluated. FeSt 1-457 was found to be magnetically supercritical near the center ($\lambda \approx 2$), whereas nearly critical or slightly subcritical at the core boundary ($\lambda \approx 0.98$). Ambipolar-diffusion-regulated star formation models for the case of moderate magnetic field strength may explain the physical status of FeSt 1-457. The mass-to-flux ratio distribution for typical dense cores (critical Bonnor--Ebert sphere with central $\lambda=2$ and $\kappa=1/2$--$2/3$) was calculated and found to be magnetically critical/subcritical at the core edge, which indicates that typical dense cores are embedded in and evolve from magnetically critical/subcritical diffuse surrounding medium., Comment: Accepted to the Astrophysical Journal (ApJ)

We performed near-infrared line mapping of the supernova remnant IC 443 with the IRSF 1.4-m telescope, using the narrow-band filters tuned for [Fe II] 1.257 μm, [Fe II] 1.644 μm, and Paβ. We detected the [Fe II] and Paβ emissions from a very wide area of the observed region ( 30 ′ × 35 ′ ). These line intensity maps reveal a global correlation between [Fe II] and Paβ. Kokusho et al. (2013) found that the [Fe II] emission is notably strong while dust emission is faint in inner regions of IC 443. These results indicate that the abundant Fe+ is likely to be of interstellar origins through shock destruction of dust, rather than of ejecta origins. From the X-ray intensity map of the 6.7 keV Fe-K line obtained with Suzaku, we find that highly ionized He-like Fe ions exist in the inner regions of IC 443, toward which Fe+ is detected. The presence of the He-like Fe ions and the faint dust emission indicates that Fe is likely to be interacting with X-ray plasma for a time long enough to be highly ionized. We discuss the implications of the detection of the lowly ionized Fe ions in such regions for the processing and composition of dust in the interstellar environment around IC 443.

We present the discovery of two new X-ray transients in archival Chandra data. The first transient, XRT 110103, occurred in January 2011 and shows a sharp rise of at least three orders of magnitude in count rate in less than 10 s, a flat peak for about 20 s and decays by two orders of magnitude in the next 60 s. We find no optical or infrared counterpart to this event in preexisting survey data or in an observation taken by the SIRIUS instrument at the Infrared Survey Facility 2.1 yr after the transient, providing limiting magnitudes of J>18.1, H>17.6 and Ks>16.3. This event shows similarities to the transient previously reported in Jonker et al. which was interpreted as the possible tidal disruption of a white dwarf by an intermediate mass black hole. We discuss the possibility that these transients originate from the same type of event. If we assume these events are related a rough estimate of the rates gives 1.4*10^5 per year over the whole sky with a peak 0.3-7 keV X-ray flux greater than 2*10^-10 erg cm^-2 s^-1 . The second transient, XRT 120830, occurred in August 2012 and shows a rise of at least three orders of magnitude in count rate and a subsequent decay of around one order of magnitude all within 10 s, followed by a slower quasi-exponential decay over the remaining 30 ks of the observation. We detect a likely infrared counterpart with magnitudes J=16.70+/-0.06, H=15.92+/-0.04 and Ks=15.37+/-0.06 which shows an average proper motion of 74+/-19 milliarcsec per year compared to archival 2MASS observations. The JHKs magnitudes, proper motion and X-ray flux of XRT 120830 are consistent with a bright flare from a nearby late M or early L dwarf., Accepted for publication in MNRAS, 6 pages, 5 figures

In cardiac myocytes, regulation of mitochondrial Ca2+ is important for cellular signaling and cardiac contraction. Ca2+ entry into the mitochondria is mediated by a highly selective Ca2+ channel called the mitochondrial calcium uniporter, which consists of a pore-forming subunit MCU and regulatory subunits such as MICU1. Although pharmacological regulation of the mitochondrial Ca2+ influx is a promising approach to controlling the cellular functions, a cell-permeable and specific inhibitor of the mitochondrial calcium uniporter has not yet been developed. Here, we identify a novel cell-permeable inhibitor of the uniporter by a high-throughput screening of 120 000 small-molecule compounds. In our study, DS16570511 dose-dependently inhibited serum-induced mitochondrial Ca2+ influx in HEK293A cells with an IC50 of 7 μM. DS16570511 inhibited Ca2+ uptake of isolated mitochondria from human cells, rat heart and pig heart. Overexpression of hMCU or hMICU1 in HEK293A cells increased mitochondrial Ca2+ influx, and the increases were completely suppressed by the pretreatment with DS16570511. DS16570511 also blocks mitochondrial Ca2+ overload in a Langendorff perfused beating rat heart. Interestingly, DS16570511 increased cardiac contractility without affecting heart rate in the perfused heart. These results show that DS16570511 is a novel cell-permeable inhibitor of the mitochondrial calcium uniporter and applicable for control of the cardiac functions.

We present the early-phase spectra and the light curves of the broad-lined supernova (SN) 2016coi from $t=7$ to $67$ days after the estimated explosion date. This SN was initially reported as a broad-lined Type SN Ic (SN Ic-BL). However, we found that spectra up to $t=12$ days exhibited the He~{\sc i} $\lambda$5876, $\lambda$6678, and $\lambda$7065 absorption lines. We show that the smoothed and blueshifted spectra of normal SNe Ib are remarkably similar to the observed spectrum of SN 2016coi. The line velocities of SN 2016coi were similar to those of SNe Ic-BL and significantly faster than those of SNe Ib. Analyses of the line velocity and light curve suggest that the kinetic energy and the total ejecta mass of SN 2016coi are similar to those of SNe Ic-BL. Together with broad-lined SNe 2009bb and 2012ap for which the detection of He~{\sc i} were also reported, these SNe could be transitional objects between SNe Ic-BL and SNe Ib, and be classified as broad-lined Type `Ib' SNe (SNe `Ib'-BL). Our work demonstrates the diversity of the outermost layer in broad-lined SNe, which should be related to the variety of the evolutionary paths., Comment: 9 pages, 10 figures. Accepted for publication in ApJ

We present the results of multi-epoch VLBI observations of water masers in the AGFL 5142 massive star forming region. We measure an annual parallax of $\pi=0.467 \pm 0.010$ mas, corresponding to a source distance of $D=2.14^{+0.051}_{-0.049}$ kpc. Proper motion and line of sight velocities reveal the 3D kinematics of masers in this region, most of which associate with millimeter sources from the literature. In particular we find remarkable bipolar bowshocks expanding from the most massive member, AFGL 5142 MM1, which are used to investigate the physical properties of its protostellar jet. We attempt to link the known outflows in this region to possible progenitors by considering a precessing jet scenario and we discuss the episodic nature of ejections in AFGL 5142.

Three dimensional (3D) magnetic field information on molecular clouds and cores is important for revealing their kinematical stability (magnetic support) against gravity which is fundamental for studying the initial conditions of star formation. In the present study, the 3D magnetic field structure of the dense starless core FeSt 1-457 is determined based on the near-infrared polarimetric observations of the dichroic polarization of background stars and simple 3D modeling. With an obtained angle of line-of-sight magnetic inclination axis $\theta_{\rm inc}$ of $45^{\circ}\pm10^{\circ}$ and previously determined plane-of-sky magnetic field strength $B_{\rm pol}$ of $23.8\pm12.1$ $\mu{\rm G}$, the total magnetic field strength for FeSt 1-457 is derived to be $33.7\pm18.0$ $\mu{\rm G}$. The critical mass of FeSt 1-457, evaluated using both magnetic and thermal/turbulent support is ${M}_{\rm cr} = 3.70\pm0.92$ ${\rm M}_{\odot}$, which is identical to the observed core mass, $M_{\rm core}=3.55\pm0.75$ ${\rm M}_{\odot}$. We thus conclude that the stability of FeSt 1-457 is in a condition close to the critical state. Without infalling gas motion and no associated young stars, the core is regarded to be in the earliest stage of star formation, i.e., the stage just before the onset of dynamical collapse following the attainment of a supercritical condition. These properties would make FeSt 1-457 one of the best starless cores for future studies of the initial conditions of star formation., Comment: Accepted to the Astrophysical Journal (ApJ)

The first detected gravitational wave from a neutron star merger was GW170817. In this study, we present J-GEM follow-up observations of SSS17a, an electromagnetic counterpart of GW170817. SSS17a shows a 2.5-mag decline in the $z$-band from 1.7 days to 7.7 days after the merger. Such a rapid decline is not comparable with supernovae light curves at any epoch. The color of SSS17a also evolves rapidly and becomes redder for later epochs; the $z-H$ color changed by approximately 2.5 mag in the period of 0.7 days to 7.7 days. The rapid evolution of both the optical brightness and the color are consistent with the expected properties of a kilonova that is powered by the radioactive decay of newly synthesized $r$-process nuclei. Kilonova models with Lanthanide elements can reproduce the aforementioned observed properties well, which suggests that $r$-process nucleosynthesis beyond the second peak takes place in SSS17a. However, the absolute magnitude of SSS17a is brighter than the expected brightness of the kilonova models with the ejecta mass of 0.01 $\Msun$, which suggests a more intense mass ejection ($\sim 0.03 \Msun$) or possibly an additional energy source., Comment: 7 pages, 5 figures. Published in PASJ (Publications of the Astronomical Society of Japan)