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A percutaneous transcatheter balloon dilation of a pulmonary venous pathway obstruction was successfully performed in a 40-year-old patient after a Mustard procedure. During the procedure, real-time three-dimensional trans-oesophageal echocardiography demonstrated the morphology of the obstruction. Our case highlights the usefulness of real-time three-dimensional trans-oesophageal echocardiography as a guide for transcatheter intervention in the increasing number of adults with CHD.
Luminescent oxygen sensor composed of platinum-porphyrin and a gas-permeable polymer binder was applied as an optical crack sensor paint for infrastructure. The sensor paints were designed as a three-layered structure in which the luminescent oxygen sensor layer was sandwiched between oxygen barrier layers. The sensor paints emitted intense luminescence under UV light irradiation, and the luminescence was efficiently quenched when a new crack formed on the concrete surface. Microcracks, which were <0.1 mm width and hardly visible to the naked eye, were clearly visualized under UV light irradiation due to the luminescent quenching caused by oxygen diffusion.
Eighty-six new acoustic survey lines along and across the Japan Trench revealed active sediment creep deformation on a deep-sea terrace at water depths of 400–1200 m in an area of arcuate-shaped depressions that are probably associated with tectonic erosion. The most active region of creep is located on the top at the surface of the depression south of 38° N. The area of creep deformation is characterized by arcuate-shaped topographic lineaments with active folds and active normal faults stepping down trenchward. In contrast to the southern region, normal faults at the top of the depression north of 38° N cut a sedimentary sequence (Unit 1) that is acoustically transparent with continuous weak reflectors, and this is covered by the undeformed layered sediment sequence of Unit 2. Unit 2 corresponds to the period of rising sea level that extended from the latest Pleistocene to the early Holocene (14–6 ka). Thus, creep is ongoing at the top of the depression south of 38° N in the surface layer, whereas it stopped north of the depression between 14 and 6 ka. These observations might indicate that the active region jumped from north to south due to probably retrogressive sliding.
Current evidence suggests that the aetiology of congenital gastrointestinal (GI) tract atresia is multifactorial, and not based solely on genetic factors. However, there are no established modifiable risk factors for congenital GI tract atresia. We used data from a Japanese nationwide birth cohort study launched in 2011, and examined whether fish consumption in early pregnancy was associated with congenital GI tract atresia. We analysed data of 89 495 women (mean age at delivery=31·2 years) who delivered singleton live births without chromosomal anomalies. Based on the results of the FFQ, we estimated the daily intake of fish and n-3 PUFA consumption in early pregnancy. We defined a composite outcome (oesophageal atresia, duodenal atresia, jejunoileal atresia and/or anorectal malformation) as congenital GI tract atresia. In this population, median fish intake was 31·9 g/d, and seventy-four cases of congenital GI tract atresia were identified. Fish consumption in early pregnancy was inversely associated with the composite outcome (multivariable-adjusted OR for the high v. low consumption category=0·5, 95 % CI 0·3, 1·0). For all the specific types of atresia, decreased OR were observed in the high consumption category, although not statistically significant. Reduced atresia occurrence was observed even beyond the US Food and Drug Administration’s recommended consumption of no more than 340 g/week. Also, n-3 PUFA-rich fish and n-3 PUFA consumptions tended to be inversely associated with atresia. Fish consumption in early pregnancy may be a preventive factor for congenital GI tract atresia.
In two major solar flares, we have found evidence for hard X-ray footpoint emission using the X-ray imager on Hinotori. Possible factors are discussed as to why we only rarely detect footpoint emissions, which may not always take the form of double sources, depending on magnetic configurations in flares.
There are some existing barriers posed by neuropsychological tests that interfere with the assessment of cognitive functioning by staff who work in long-term care facilities. The purpose of this study was to investigate the feasibility of assessing cognitive function through conversation.
A total of 100 care staff was randomly selected as participants. Each staff member evaluated cognitive function in one to three residents using the Conversational Assessment of Neurocognitive Dysfunction (CANDy), which is a screening test for dementia using conversation. Other scales used were the Mini-Mental State Examination (MMSE), Behavioral Pathology in Alzheimer’ s Disease (BEHAVE-AD), and quality-of-life questionnaire for the elderly with dementia (QOL-D).
A total of 80 care staff members and 158 residents were analyzed. When the CANDy involved an evaluation based on face-to-face communication, it demonstrated significant correlations with the MMSE, BEHAVE-AD, and several indices of the QOL-D (e.g. negative affect and actions, communication ability, restless, and spontaneity and activity). In contrast, when the CANDy involved an evaluation based on an impression of a typical conversation, it only demonstrated significant relationships with the MMSE and the spontaneity and activity index of the QOL-D.
Conversational assessment is a useful means to assess cognitive functioning and to promote interactions between residents and care staff in long-term care facilities.
Recent observations revealed that many kinds of astrophysical outflows have very similar structure, i.e. bipolar jets are surrounded by an equatorial (disk-shaped) wind or an expanded wind as in the outflows from YSO's, post AGB stars, pulsars or AGN's. One might think that this is very queer because the species of the central objects and the spatial scales are quite different among these objects. However this similarity is a result of self-organized magnetospheric equilibrium. In these systems, the rotating magnetic field plays an important role for the structure formation. In such systems, two components of the Lorentz force (the electrostatic force and the magnetic force arising from the toroidal component) dominate other forces in the region far distant from the rotation axis in spite of the difference of the acceleration mechanism of the flows. We can understand that such similarity of the structures is a nature of the plasma outflows itself.
We suppose relativistic, pressure-free, inviscid, resistive-less, stationary and axisymmetric MHD flows. In this case, MHD equations reduce to well known basic equations: the Bernoulli equation and the Grad-Shafranov equation. We should note that the special relativistic treatment is necessary to discuss the structure far beyond the light cylinder, even if the flow speed is not close to the light velocity.
The aim of this work is to demonstrate the properties of the magnetospheric model around Kerr black holes, so-called the “flywheel” (rotation powered) model. The fly-wheel engine of the BH accretion disk system is applied to the statistics of QSOs/AGNs. Nitta, Takahashi, & Tomimatsu clarified the individual evolution of the Kerr black-hole fly-wheel engine, which is parameterized by black-hole mass, initial Kerr parameter, magnetic field near the horizon, and a dimensionless small parameter. We impose a statistical model for the initial mass function of an ensemble of black holes using the Press-Schechter formalism. With the help of additional assumptions, we can discuss the evolution of the luminosity function and the spatial number density (population) of QSOs/AGNs. The result explains well the decrease of very bright QSOs and decrease of population after z ~ 2.
We present multi-instrument observations of AR 8048, made between June 3 and June 5 1997 as part of SoHO JOP033. This active region (AR) has a sigmoid-like global shape and undergoes transient brightenings through which the stored energy is released.
Using a magneto-hydrostatic model, we compute coronal magnetic field. The large-scale magnetic lines confirm the sigmoidal characteristics of the AR. The field lines most closely matching the hotter SoHO/CDS loops extend along the quasi-separatrix-Iayers (QSLs) of the coronal field. Transition region (TR) brightenings observed with SoHO/CDS can be associated with both QSL intersections with the photosphere, and places where separatrices corresponding to bald patches (BPs, sites where field lines are tangent to the photosphere) lie at the photospheric plane. There are suggestions that the element abundances measured in the TR may depend on the type of topological structure present. TR brightenings associated with QSLs have coronal abundances, while those associated with BP separatrices have abundances closer to photospheric values.
In a few recent studies, 8 coronal mass ejections (CMEs) were identified to associate with a superactive region, AR 8100. They were all flare-CME events, It is found that the region is characterized by vigorous flux emergence and an imbalance of magnetic flux in two polarities. With the continuous flux emergence and its driven flux cancellation, the EUV dimming associated with flare activity increased in area. Whenever the dimming extended to an area of more than 50×50 square degrees on the solar surface, a flare in the region became CME-associated.
We are searching for pulsations in cool (< 6000 K) white dwarfs (WDs), hoping to apply asteroseismological techniques to improve our understanding of their structure and the physical processes inside them. This information is important as we use cool WDs to estimate the lower limit of the age of the Galactic disk. Within a spectroscopic and photometric survey of 110 cool WDs by Bergeron, Ruiz, & Legget, we find 28 candidates with appropriate effective temperatures, masses, and chemical compositions for possible pulsations in nonradial g modes with periods similar to those we observe in DAVs. So far, we have observed 4 candidates, but have found no evidence of large variation.
During the September 1996 campaign of multi-wavelength observations with the SOHO (SUMER, CDS, EIT, MDI, LASCO) and Yohkoh (SXT) spacecraft, the HAO Mauna Loa Solar Observatory Chromospheric Helium Imaging Photometer and the Nobeyama radioheliograph, a filament disparition brusque (DB) associated with a Coronal Mass Ejection (CME) was observed. The timeline of this complex event, which lasted for tens of hours, shows that the CME had started before the DB of a filament, while the main “bubble” of the CME was probably launched hours after the DB from the so-called “zipper” region. All these suggest that a general reorganization of large-scale fields was taking place on the Sun, and both the DB and the CME were symptoms of this.
The origin of the helium-atmosphere DB white dwarfs is still a matter of debate. In particular, the question is unresolved whether binary evolution produces a significant number of DBs. The pulsating DB white dwarfs (DBV stars) offer a complementary insight into this problem through asteroseismology; DBs descending from binaries will have different interior structures than DBs originating from single stars (Nitta & Winget, 1998).
GD 358 is by far the best-observed pulsating DBV star, and the only one for which asteroseismology has been performed to date. This star’s structure has been shown to be inconsistent with an origin from binary evolution (Nitta & Winget, 1998), but most of the other DBVs are relatively poorly studied.
We therefore analysed archival data on all DBVs and obtained new measurements of stars with very little data available (Table 1), firstly to identify suitable targets for asteroseismological investigations and secondly to examine the pulsation spectra of the DBVs as a group, following the works of Clemens (1994) and Kleinman (1995) on the pulsating DA white dwarfs. Our study also produced new seismological results on individual stars and promising targets for future Whole Earth Telescope (WET, Nather et al., 1990) runs.
Non force-free cylindrical equilibrium of the magnetically driven relativistic MHD flows is investigated as a model of astrophysical jets/winds. This work is a generalization of the previous work Nitta (1995). We consider the situation that the magnetic field lines emanated from the central object are rotating, and the frozen plasmas are magnetically accelerated outward and construct a self-organized magnetosphere due to the Lorentz force and the inertial force. Recent observations revealed that many objects have a hybrid structure of collimated jet and non-collimated wind regardless with species of the central object, e.g. YSO’s, stars, pulsars or AGN’s. In order to explain these structures, we present a model that the magnetosphere has a hybrid asymptotic structure: the cylindrical jet and the conical wind fill the infinitely distant polar region and the lower latitude region, respectively. The asymptotically conical wind was investigated in the previous paper (Nitta 1994). Here we investigate the asymptotically cylindrical jet at ‘finite cylindrical radius’ from the rotational axis. In this case, the inertial force is important for the force balance because a fraction of the flows having finite angular momentum converges to finite cylindrical radius.
The variability of CD-24 7599 (V=11.48 mag) was discovered by JCC during observing run XCOV7 of the Whole Earth Telescope (WET, Nather et al. 1990) network in February, 1992. The star was observed as an additional target and 117 hours of high-quality temporal spectroscopic observations were obtained.
Our analysis of these data revealed the presence of 7 independent pulsation modes between 27.0 and 38.1 cycles per day (313 – 441 μHz) with semiamplitudes of 2.1 – 10.2 milli-modulation amplitudes (mma). We showed that peaks at linear combination frequencies detected in the power spectra were not due to eigenmodes excited to visible amplitude by resonant mode coupling.
We study fundamental properties of transonic galactic outflows in the gravitational potential of a cold dark matter halo (DMH) with a central super-massive black hole (SMBH) assuming a polytropic, steady and spherically symmetric state. We have classified the transonic solutions with respect to their topology in the phase space. As a result, we have found two types of transonic solutions characterized by a magnitude relationship between the gravity of DMH and that of SMBH. These two types of solutions have different loci of the transonic points; one transonic point is formed at a central region (< 0.01kpc) and another is at a distant region (> 100kpc). Also, mass fluxes and outflow velocities are different between the two solutions. These two transonic solutions may play different roles on the star formation history of galaxies and the metal contamination of intergalactic space. Furthermore, we have applied our model to the Sombrero galaxy. In this galaxy, the wide-spread hot gas is detected as an apparent trace of galactic outflows while the star-formation rate is disproportionately low, and the observed gas density distribution is quite similar to the hydrostatic state (Li et al. 2011). To solve this discrepancy, we propose a slowly accelerating outflow in which the transonic point forms in a distant region (~ 120 kpc) and the subsonic region spreads across the stellar distribution. In the subsonic region, the gas density distribution is similar to that of the hydrostatic state. Our model predicts the possibility of the slowly accelerating outflow in the Sombrero galaxy. Igarashi et al. 2014 used the isothermal model and well reproduced the observed gas density distribution, but the estimated mass flux (1.8M⊙/yr) is lager than the mass of the gas supplied by stars (0.3-0.4M⊙/yr). Then, we expect that the polytropic model may reproduce the observational mass of the supplied gas (Igarashi et al. 2015). Such slowly accelerating outflows should be distinguished from the conventional supersonic outflows frequently argued in star-forming galaxies.
We study fundamental properties of transonic galactic outflows in the gravitational potential of a cold dark matter halo (DMH) with a central super-massive black hole (SMBH) assuming an isothermal, steady and spherically symmetric state. Transonic solutions of galactic outflows are classified according to their topological features. As result, we find two types of transonic solutions distinguished by a magnitude relationship between the gravity of DMH and that of SMBH. The loci of transonic points for two types are different; one transonic point is formed at a central region (< 0.01kpc) and another is at a very distant region (> 100kpc). Also, mass fluxes and outflow velocities are different for two solutions. Thus, these solutions may differently influence the evolution of galaxies and the release of metals into the intergalactic space.
Furthermore, we apply our model to the Sombrero galaxy. In this galaxy, the wide-spread hot gas is detected as the trace of galactic outflows while the star-formation rate is low, and the observed gas density distribution is similar to the hydrostatic state (Li et al. 2011). To solve this discrepancy, we propose a solution that this galaxy has a slowly accelerating outflow; the transonic point forms in a very distant region (~ 120 kpc) and the wide subsonic region spreads across the stellar distribution. Thus, the gas density distribution in the observed region is similar to the hydrostatic state. Such slowly accelerating outflows are different from high-velocity outflows conventionally studied (Igarashi et al. 2014).
However, this isothermal model requires an unrealistically large mass flux. Then, we apply the polytropic model to this galaxy incorporating mass flux supplied by stellar components. We find that it can reproduce the observed gas density and the temperature distributions with the realistic mass flux. Thus, our polytropic model successfully demonstrates the existence of the slowly accelerating outflow in the Sombrero galaxy (Igarashi et al. 2015).
We are trying to reduce the largest uncertainties in using white dwarf stars as Galactic chronometers by understanding the details of carbon crystalliazation that currently result in a 1–2 Gyr uncertainty in the ages of the oldest white dwarf stars. We expect the coolest white dwarf stars to have crystallized interiors, but theory also predicts hotter white dwarf stars, if they are massive enough, will also have some core crystallization. BPM 37093 is the first discovered of only a handful of known massive white dwarf stars that are also pulsating DAV, or ZZ Ceti, variables. Our approach is to use the pulsations to constrain the core composition and amount of crystallization. Here we report our analysis of 4 hours of continuous time series spectroscopy of BPM 37093 with Gemini South combined with simultaneous time-series photometry from Mt. John (New Zealand), SAAO, PROMPT, and Complejo Astronomico El Leoncito (CASLEO, Argentina).
The behavior of threading dislocations during mass transport of GaN was investigated in detail by transmission electron microscopy. Mass transport occurred at the surface. Therefore, growing species are supplied from the in-plane direction. The behavior of threading dislocations was found to be strongly affected by the mass transport process as well as the high crystallographic anisotropy of the surface energy of the facets particular to GaN.
A study of the optoelectronic properties of strained 40 nm Ga1−xInxN layers on GaN films is presented. The fact of pseudomorphic strain leads to a new interpretation of the film composition when derived from x-ray scattering. In addition we directly confirm that strain induces huge piezoelectric fields in this uniaxial system by the observation of Franz-Keldysh oscillations in photoreflection. As a function of composition (0 < x < 0.2) and strain we derive the electronic band gap energy and the piezoelectric field strength. We interpret both in terms of effective bowing parameters and piezoelectric coefficients, respectively. From a spatially resolved micro photoluminescence at room temperature we find no evidence for spatial band gap or composition variations of more than 60 meV over the length scale from 1 to 50 μm (x=0.187) in our material. At the same time, an observed discrepancy between photoluminescence peak energy and photoreflection band gap energy increases with x to some 160 meV. We attribute this redshift to photon assisted tunneling in the huge piezoelectric fields (Franz-Keldysh effect).