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We have reported a blood flow increase in the prefrontal cortex during the performance of the computer version TMT. Although TMT-A was first performed and followed by TMT-B in the previous study, the order was reversed in the present study,i.e., TMT-B was first performed and then followed by TMT-A, and differences in the change of blood flow were compared between the two modes of TMT.
Nine healthy student volunteers (20.7 ± 1.6 yr) performed two different sets of TMT-B. After a resting period of 30 sec, they performed four different sets of TMT-A. Changes of oxyHb and deoxyHb were monitored by 22-channel NIRS from 30 sec before the start of TMT-B through 30 sec after the end of TMT-A. The mean changes of blood flow over a period of 10 sec just before the start of TMT-B and TMT-A, and over a period of 100 sec after the start of TMT-B and TMT-A were determined.
The increase of oxyHb was prominent in the right lateral prefrontal cortex.
The results suggest that the blood flow increases in the prefrontal cortex during the start of either TMT-A or TMT-B. The location of blood flow increase did not change whether TMT-B was performed first or after TMT-A. Therefore, the blood flow increase observed only in the right prefrontal cortex in the previous study could not be due to familiarization of the test. In contrast, TMT-A apparently exhibits a familiarization effect, since blood flow increase was not observed when TMT-A was performed after TMT-B.
We measured concentration changes of oxyHb and deoxyHb in the prefrontal cortex during the performance of the computer version Trail Making Test(TMT) by multichannel NIRS using near infrared light pairs which are more sensitive for detecting changes of oxyHb and deoxyHb.
Sixteen healthy student volunteers performed four different TMT-A sets, and following 30 a sec resting period, two different TMT-B sets. Changes of oxyHb and deoxyHb were monitored by 22 channel NIRS from 30 sec before the start of TMT-A through 30 sec after the end of TMT-B. The mean changes in subjects over a period of 10 sec just before the start of TMT-A and TMT-B, and a period of 50 to 60 sec after the start of TMT-A and TMT-B were determined. OxyHb increased while deoxyHb decreased in the bilateral prefrontal cortices during the performance of TMT. The increase of oxyHb was prominent in the right lateral prefrontal cortex, especially during TMT-A.
On the other hand, deoxyHb significantly decreased in the bilateral prefrontal cortices especially during TMT-A.
The results suggest that blood flow increases in the prefrontal cortex during the performance of the computer version TMT.
We present ALMA detection of the [O iii] 88 μm line and 850 μm dust continuum emission in a Y-dropout Lyman break galaxy, MACS0416_Y1. The [O iii] detection confirms the object with a spectroscopic redshift to be z = 8.3118±0.0003. The 850 μm continuum intensity (0.14 mJy) implies a large dust mass on the order of 4×106M⊙. The ultraviolet-to-far infrared spectral energy distribution modeling, where the [O iii] emissivity model is incorporated, suggests the presence of a young (τage ≍ 4 Myr), star-forming (SFR ≍ 60M⊙yr−1), and moderately metal-polluted (Z ≍ 0.2Z⊙) stellar component with a stellar mass of 3 × 108M⊙. An analytic dust mass evolution model with a single episode of star formation does not reproduce the metallicity and dust mass in ≍ 4 Myr, suggesting an underlying evolved stellar component as the origin of the dust mass.
In recent years, the discovery of massive quasars at
has provided a striking challenge to our understanding of the origin and growth of supermassive black holes in the early Universe. Mounting observational and theoretical evidence indicates the viability of massive seeds, formed by the collapse of supermassive stars, as a progenitor model for such early, massive accreting black holes. Although considerable progress has been made in our theoretical understanding, many questions remain regarding how (and how often) such objects may form, how they live and die, and how next generation observatories may yield new insight into the origin of these primordial titans. This review focusses on our present understanding of this remarkable formation scenario, based on the discussions held at the Monash Prato Centre from November 20 to 24, 2017, during the workshop ‘Titans of the Early Universe: The Origin of the First Supermassive Black Holes’.
Symmetric and triangle-shaped flux variability in X-ray and gamma-ray light curves is observed from many blazars. We derived the X-ray spectrum changing in time by using a kinetic equation of high energy electrons. Giving linearly changing the injection of low energy electrons into accelerating and emitting region, we obtained the preliminary results that represent the characteristic X-ray variability of the linear flux increase with hardening in the rise phase and the linear decrease with softening in the decay phase.
Several strategies have been explored from viewpoint of biomimetics to accomplish artificial photosynthesis by using macromolecules as a medium such as liposomes, supramolecules, and hydrogels.1 Differing from disordered solution systems in which multiple components such as photosensitizer and catalytic nanoparticle are diffusively mixed, the photochemical reactions occur efficiently in medium due to maintenance of the dipersibility of the components and specific molecular arrangement. Here we attempt to clarify the effect of medium hierarchy for photoinduced electronic transmission among multiple components. By conjugating each component on tubulin and integrating them via self-assembly to microtubules, ideal component arrangements with optimum distance for the electronic transmission will be possible.
It is difficult to get a real scale image of the solar system through lecture. A scale model is a classical and one of good solutions (e.g. Handa et al.2003, Handa et al.2008). Through this model, people living in or visiting to the city can physically understand the scale of the solar system. This scale gives 1 cm for Earth's diameter and 115 m for 1 AU. However, some gadget is required to make it attractive for public citizens.
The current trends in stimulated Brillouin scattering and optical phase conjugation are overviewed. This report is formed by the selected papers presented in the “Fifth International Workshop on stimulated Brillouin scattering and phase conjugation 2010” in Japan. The nonlinear properties of phase conjugation based on stimulated Brillouin scattering and photo-refraction can compensate phase distortions in the high power laser systems, and they will also open up potentially novel laser technologies, e.g., phase stabilization, beam combination, pulse compression, ultrafast pulse shaping, and arbitrary waveform generation.
Single-crystalline organic solar cells were investigated. Rubrene single crystals made by train sublimation method were used for the active layer of the solar cells. Typical solar cell characteristics and external quantum efficiency (EQE) were observed with the film thickness of several micrometers. In spite of their large film thickness, the EQE spectra showed no screening effect, which means that absorbed photons efficiently converted to electric charges. This can be attributed to the extended exciton diffusion due to uniform and trap free characteristic of rubrene single crystal.
The present work has been done within the IAEA Environmental Modelling for Radiation Safety Programme. EMRAS-II aims to improve the capabilities in the field of environmental radiation dose assessment by means of acquisition of improved data for model testing, comparison, reaching consensus on modelling philosophies, approaches and parameter values, development of improved methods and exchange of information.
Recently the Flash Memory is scaling limit, Thus the Memory of various types is now under study for the next generation large capacity nonvolatile memory. Resistance random access memory (ReRAM) is attracts much attention due to its advantage for integration in the next generation nonvolatile memory, because it is depend on scaling by lithography compared with the Flash Memory of capacity type. The material for ReRAM is classified roughly into binary oxides and perovskite oxides. Several binary oxides such as a TaOx have the advantage for low-temperature process and low-cost materials compared with perovskite oxides such as a (Pr,Ca)MnO3 (PCMO). In this study, TaOx film with the thickness of 10nm were prepared by reactive RF magnetron sputtering on 8inch-Pt/Si substrate using a Ta metal target in oxygen ambient. The sputtering system was the multi chamber type mass production tool. The TaOx thin film was amorphous phase as a result of measurement by X-ray diffraction meter. Ta top electrodes with 50 um diameters were deposited on the surface of TaOx layer by the DC sputtering method using a shadow mask. The “Forming” voltage of TaOx-ReRAM was 5.0V. After “Forming” process, the “Set” and “Reset” voltage were 3.0V and –3.0V respectively. It has good switching properties with large on/off resistance ratio above 1,000.
In the last decade, a declining prevalence of HCV infection has been described in injecting drug users (IDUs) in different countries. This study is the first to assess temporal trends in drug-injecting patterns, HCV infection rates and viral genotype distribution in 770 Brazilian IDUs, recruited by two cross-sectional studies (1994–1997 and 1999–2001). A substantial decline in the prevalence of HCV infection was found over the years (75% in 1994 vs. 20·6% in 2001, P<0·001) that may be a consequence of the significant reduction in the overall frequencies of drug injection and needle-sharing, as well as the participation of IDUs in initiatives aimed at reducing drug-related harm. No trend was found in terms of viral genotype distribution. Despite the favourable scenario, preventive measures must be maintained, especially in vulnerable subgroups such as young or new injectors, where risky behaviours through direct and indirect sharing practices remain common.
We have shown that variation in the real part of the dielectric permittivity of typical transparent conducting oxide (TCO) films can have a profound effect on the optical properties of the material. This has been demonstrated by adding small amounts of Zr to an ITO ceramic sputtering target and analyzing the resulting ITO and ITO:Zr (ITZO) films. Comparative electrical and optical analyses of the films show that, although the carrier concentration and mobility do not change appreciably by adding 1 wt.% ZrO2 to the ITO sputtering target, the plasma wavelength increases significantly for the ITZO film. We believe that the underlying physics of these results can be exploited in designing future TCO films for photovoltaic (PV) applications—especially those that embody industrial advantages but remain limited by low mobility.
Modern in situ survey technologies such as crewed submersibles, remotely-operated vehicles (ROVs), towed camera arrays, and visual/video plankton recorders (VPRs) were used to characterize the dominant anthomedusan species off the eastern seaboard of Japan. Notes on the taxonomy, distribution, behaviour and interspecies interactions are presented for the four observed species: Euphysa japonica, E. flammea, Calycopsis nematophora and Pandea rubra. A new generic definition for the genus Calycopsis is proposed. The possibility of run-on, cascading detrimental effects of oceanic acidification on midwater ecosystems was identified from observations made during the present study.
An overview on current trends in stimulated Brillouin scattering and optical phase conjugation is given. This report is based on the results of the “Second International Workshop on stimulated Brillouin scattering and phase conjugation” held in Potsdam/Germany in September 2007. The properties of stimulated Brillouin scattering are presented for the compensation of phase distortions in combination with novel laser technology like ceramics materials but also for e.g., phase stabilization, beam combination, and slow light. Photorefractive nonlinear mirrors and resonant refractive index gratings are addressed as phase conjugating mirrors in addition.