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The multiphase simulations are conducted with the kinetic-magnetohydrodynamics hybrid code MEGA to investigate the spatial and the velocity distributions of lost fast ions due to the Alfvén eigenmode (AE) bursts in the Large Helical Device plasmas. It is found that fast ions are lost along the divertor region with helical symmetry both before and during the AE burst except for the promptly lost particles. On the other hand, several peaks are present in the spatial distribution of lost fast ions along the divertor region. These peaks along the divertor region can be attributed to the deviation of the fast-ion orbits from the magnetic surfaces due to the grad-B and the curvature drifts. For comparison with the velocity distribution of lost fast ions measured by the fast-ion loss detector (FILD), the ‘numerical FILD’ which solves the Newton–Lorentz equation is constructed in the MEGA code. The velocity distribution of lost fast ions detected by the numerical FILD during AE burst is in good qualitative agreement with the experimental FILD measurements. During the AE burst, fast ions with high energy (100–180 keV) are detected by the numerical FILD, while co-going fast ions lost to the divertor region are the particles with energy lower than 50 keV.
The neutral beam (NB) fast ion confinement in the Large Helical Device (LHD) is studied for several full field (
) magnetic configurations by a combination of neutron measurement and simulations. To investigate the NB fast ion confinement, we have performed a series of short-pulse NB injection experiments. The experiment results are analysed by the integrated code TASK3D-a. From this investigation, the effective particle diffusion coefficients of the tangential and perpendicular NBs are approximately
in the standard configuration. It is clarified that the NB fast ion confinement improves when the plasmas are shifted inward. Moreover, it is also found that the simulation, which considers the deuteron dilution effect due to the presence of impurity ions, can describe a neutron emission rate consistent with the measurement.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
To assess the diagnostic role of mean platelet volume in tonsillitis with and without peritonsillar abscess.
Mean platelet volume and other laboratory data were retrospectively investigated.
Mean platelet volume was significantly lower in the tonsillitis group (7.8 per cent ± 0.7 per cent) than in the control group (8.7 per cent ± 0.6 per cent; p < 0.0001), and it was significantly lower in the abscess group (7.5 per cent ± 0.6 per cent) than in the no abscess group (8.0 per cent ± 0.7 per cent; p = 0.0277). White blood cell counts and C-reactive protein levels were not significantly different between patients with an abscess and those without. The mean platelet volume cut-off values for the diagnosis of tonsillitis and peritonsillar abscess were 7.95 fl and 7.75 fl, respectively.
Our results suggest that a decreased mean platelet volume is associated with the development and severity of tonsillitis. This finding provides useful diagnostic information for physicians treating patients with tonsillitis.
To determine the characteristics of acute phase nystagmus in patients with cerebellar lesions, and to identify a useful indicator for differentiating central lesions from peripheral lesions.
Acute phase nystagmus and the appearance of neurological symptoms were retrospectively investigated in 11 patients with cerebellar stroke.
At the initial visit, there were no patients with vertical nystagmus, direction-changing gaze evoked nystagmus or pure rotatory nystagmus. There were four cases with no nystagmus and seven cases with horizontal nystagmus at the initial visit. There were no neurological symptoms, except for vertigo and hearing loss, in any cases at the initial visit. The direction and type of nystagmus changed with time, and neurological symptoms other than vertigo appeared subsequently to admission.
It is important to observe the changes in nystagmus and other neurological findings for the differential diagnosis of central lesions.
To evaluate the effectiveness of tympanostomy tube placement in controlling symptoms of intractable Ménière's disease.
Fifteen patients with intractable Ménière's disease underwent tympanostomy tube placement in the affected ear. Post-operative changes in vertigo attacks and hearing level were recorded, and were evaluated according to American Academy of Otolaryngology–Head and Neck Surgery criteria.
At 12 months after treatment, 3 patients (20 per cent) showed complete control of vertigo, 7 (47 per cent) showed substantial control and 2 (13 per cent) showed limited control; 3 patients (20 per cent) required other treatment. At 24 months after treatment, 7 patients (47 per cent) showed complete control of vertigo, 3 (20 per cent) showed substantial control and 1 (7 per cent) showed limited control; 1 patient required other treatment 15 months after tympanostomy tube placement.
There is no definite pathophysiological explanation for the effect of tympanostomy tube placement in reducing vertigo attacks. This treatment is not effective for all patients with intractable Ménière's disease. However, tympanostomy tube placement might be an additional surgical therapeutic option to consider prior to contemplating other, more invasive treatments.
A fully coherent free electron laser (FEL) seeded with a higher-order harmonic (HH) pulse from high-order harmonic generation (HHG) is successfully operated for a sufficiently prolonged time in pilot user experiments by using a timing drift feedback. For HHG-seeded FELs, the seeding laser pulses have to be synchronized with electron bunches. Despite seeded FELs being non-chaotic light sources in principle, external laser-seeded FELs are often unstable in practice because of a timing jitter and a drift between the seeding laser pulses and the accelerated electron bunches. Accordingly, we constructed a relative arrival-timing monitor based on non-invasive electro-optic sampling (EOS). The EOS monitor made uninterrupted shot-to-shot monitoring possible even during the seeded FEL operation. The EOS system was then used for arrival-timing feedback with an adjustability of 100 fs for continual operation of the HHG-seeded FEL. Using the EOS-based beam drift controlling system, the HHG-seeded FEL was operated over half a day with an effective hit rate of 20%–30%. The output pulse energy was
at the 61.2 nm wavelength. Towards seeded FELs in the water window region, we investigated our upgrade plan to seed high-power FELs with HH photon energy of 30–100 eV and lase at shorter wavelengths of up to 2 nm through high-gain harmonic generation (HGHG) at the energy-upgraded SPring-8 Compact SASE Source (SCSS) accelerator. We studied a benefit as well as the feasibility of the next HHG-seeded FEL machine with single-stage HGHG with tunability of a lasing wavelength.
Streptococcal toxic shock syndrome (STSS) is a severe invasive infection characterized by the sudden onset of shock, multi-organ failure, and high mortality. In Japan, appropriate notification measures based on the Infectious Disease Control law are mandatory for cases of STSS caused by β-haemolytic streptococcus. STSS is mainly caused by group A streptococcus (GAS). Although an average of 60–70 cases of GAS-induced STSS are reported annually, 143 cases were recorded in 2011. To determine the reason behind this marked increase, we characterized the emm genotype of 249 GAS isolates from STSS patients in Japan from 2010 to 2012 and performed antimicrobial susceptibility testing. The predominant genotype was found to be emm1, followed by emm89, emm12, emm28, emm3, and emm90. These six genotypes constituted more than 90% of the STSS isolates. The number of emm1, emm89, emm12, and emm28 isolates increased concomitantly with the increase in the total number of STSS cases. In particular, the number of mefA-positive emm1 isolates has escalated since 2011. Thus, the increase in the incidence of STSS can be attributed to an increase in the number of cases associated with specific genotypes.
Using American bullfrog models under normal conditions and under vestibular dysfunction, we investigated whether mechanical vibration applied to the ear could induce otoconial dislodgement.
Vibration was applied to the labyrinth of the bullfrog using a surgical drill. The time required for the otoconia to dislodge from the utricular macula was measured. Vestibular dysfunction models were created and the dislodgement time was compared with the normal models. The morphology of the utricular macula was also investigated.
In the normal models, the average time for otoconial dislodgement to occur was 7 min and 36 s; in the vestibular dysfunction models, it was 2 min and 11 s. Pathological investigation revealed that the sensory hairs of the utricle were reduced in number and that the sensory cells became atrophic in the vestibular dysfunction models.
The otoconia of the utricle were dislodged into the semicircular canal after applying vibration. The time to dislodgement was significantly shorter in the vestibular dysfunction models than in the normal models; the utricular macula sustained significant morphological damage.
We investigated electronic structure of one-dimensional biradical molecular chain which is constructed by exploiting the covalency between organic molecules of a diphenyl derivative of s-indacenodiphenalene (Ph2-IDPL). To control the crystallinity, we used gas deposition method. Ultraviolet photoelectron spectroscopy (UPS) revealed developed band structure with wide dispersion of the one-dimensional biradical molecular chain.
To examine the clinical features, age and gender distribution of patients, treatment methods, and outcomes of benign paroxysmal positional vertigo.
This paper reports a review of 357 patients treated for this condition at a single institution over a duration of 5 years. Patients with posterior canal benign paroxysmal positional vertigo were divided into two groups: one group underwent the Epley manoeuvre and the other received medication. The lateral canal canalolithiasis patients were also divided into two groups: one underwent the Lempert manoeuvre and the other received medication. Lastly, the lateral canal cupulolithiasis patients were treated with medication and non-specific physical techniques.
Results and conclusion:
For patients with posterior canal benign paroxysmal positional vertigo, resolution time was significantly shorter in the Epley manoeuvre group than in the medication group. For the lateral canal canalolithiasis patients, resolution time was significantly shorter in the Lempert manoeuvre group than in the medication group. Resolution time was significantly longer in the lateral canal cupulolithiasis patients than in the other patients. The average age of patients increased with the number of recurrences, as did predominance in females. Average age and rate of sensorineural hearing loss were significantly higher in patients with intractable benign paroxysmal positional vertigo compared with those in the curable benign paroxysmal positional vertigo group.
To investigate what kinds of stimuli are effective in detaching otoconia from the cupula in three experimental models of cupulolithiasis.
Three experimental models of cupulolithiasis were prepared using bullfrog labyrinths. Three kinds of stimuli were applied to the experimental models. In experiment one (gravity), the labyrinth preparation was placed so that the cupula-to-crista axis was in the horizontal plane with the canal side in the downward position. In experiment two (sinusoidal oscillation), the labyrinth preparation was placed 3 cm from the rotational centre of a turntable, which was sinusoidally rotated with a rotational cycle of 1 Hz and a rotational angle of 30°. In experiment three (vibration), mechanical vibration was applied to the surface of the bony capsule around the labyrinth using a surgical drill.
In experiments one, two and three, the otoconial mass was respectively detached in 2 out of 10 labyrinth preparations, none of the labyrinth preparations, and all of the labyrinth preparations.
Vibration was the most effective stimulus for detaching the otoconia from the cupula in these experimental models of cupulolithiasis.
Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of
observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events,
using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients
as of the end of September 2012. Among them, eleven events were simultaneously detected by
other satellites. The observed rate of the MAXI GRBs is about one event per month. This
rate is comparable to a past observation with larger effective area and larger field of
view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low
background. The distribution of the spectral hardness of MAXI GRBs is similar to the
results of a past instrument, which is sensitive to similar energy range.
We carried out magnetohydrodynamic (MHD) simulations to reveal the formation mechanism of molecular towers observed in the central region of our galaxy. These molecular clouds can be formed by the interaction of magnetic tower jet with the interstellar gas. When the jet collides with dense HI clouds, the HI gas is compressed by the bow shock ahead of the jet. Since the density enhancement triggers the cooling instability because it increases the cooling rate, the shocked gas cools down and forms cold, dense gas. We carried out MHD simulations including the cooling. The magnetized jet which triggers the formation of the molecular column appears in global magnetohydrodynamic simulations of accretion disks, in which the magnetic loops emerging from the disk are twisted by the differential rotation between the footpoints of magnetic loops anchored to the disk. Numerical results indicate that the magnetic loops expand, and form a magnetic tower. When the ambient density is small, the propagation speed of the tower can be as large as the rotation speed of the disk. When the ambient density is high, the collision of the jet and the HI cloud forms dense molecular tower.
We present VLBI maps of the 6.7 GHz methanol maser emission in 32 sources obtained using the Japanese VLBI Network (JVN) and the East-Asian VLBI Network (EAVN). All of the observed sources provide new VLBI maps, and the spatial morphologies have been classified into five categories similar to the results obtained from European VLBI Network observations (Bartkiewicz et al. 2009). The 32 methanol sources are being monitored to measure the relative proper motions of the methanol maser spots.
The ‘DLC-GFET’, a graphene field effect transistor with a diamondlike carbon (DLC) top-gate dielectric film, is presented. The DLC film was formed ‘directly’ onto the graphene channel without forming passivation interlayers using our original photoemission-assisted plasma-enhanced chemical vapor deposition (PA-CVD), where the plasma was precisely controlled by photoemission from the sample with quite low electric power to minimize plasma damage to the channel. The DLC-GFET exhibits clear ambipolar characteristics with a slightly positive shift of the neutral points (Dirac voltages). Relatively high transconductances were obtained as 14.6 (8.8) mS/mm in the n (p) channel modes, respectively, with a thick gate dielectric of 48 nm and a long gate length of 5 μm, promising vertical scaling-down to improve the high-frequency performance. The positive shift of the Dirac voltage is due to unintentional hole doping from oxygen species in the DLC film into the graphene channel, promising a minute modulation doped structure with oxygen to overcome high resistance in the access region. Hence, a DLC film deposited by PA-CVD is a candidate for the gate dielectric on graphene.
The relation between chemical potential and Seebeck coefficient was investigated by using high-resolution angle resolved photoemission spectroscopy. The temperature dependence of chemical potential was experimentally determined for the n-type TiS2 thermoelectric material and compared with the measured Seebeck coefficient. We found that the temperature dependence of chemical potential of TiS2 is significantly large, and its effect on Seebeck coefficient is not negligible. This fact strongly indicates that the temperature dependence of chemical potential has to be properly understood to construct the guiding principle for developing new, practical thermoelectric materials.