44 research outputs found
Executive function after exhaustive exercise
PurposeFindings concerning the effects of exhaustive exercise on cognitive function are somewhat equivocal. The purpose of this study was to identify physiological factors that determine executive function after exhaustive exercise.MethodsThirty-two participants completed the cognitive tasks before and after an incremental exercise until exhaustion (exercise group: N = 18) or resting period (control group N = 14). The cognitive task was a combination of a Spatial Delayed-Response (Spatial DR) task and a Go/No-Go task, which requires executive function. Cerebral oxygenation and skin blood flow were monitored during the cognitive task over the prefrontal cortex. Venous blood samples were collected before and after the exercise or resting period, and blood catecholamines, serum brain-derived neurotrophic factor, insulin-like growth hormone factor 1, and blood lactate concentrations were analyzed.ResultsIn the exercise group, exhaustive exercise did not alter reaction time (RT) in the Go/No-Go task (pre: 861 ± 299 ms vs. post: 775 ± 168 ms) and the number of error trials in the Go/No-Go task (pre: 0.9 ± 0.7 vs. post: 1.8 ± 1.8) and the Spatial DR task (pre: 0.3 ± 0.5 vs. post: 0.8 ± 1.2). However, ΔRT was negatively correlated with Δcerebral oxygenation (r = −0.64, P = 0.004). Other physiological parameters were not correlated with cognitive performance. Venous blood samples were not directly associated with cognitive function after exhaustive exercise.ConclusionThe present results suggest that recovery of regional cerebral oxygenation affects executive function after exhaustive exercise
Suzaku and XMM-Newton Observations of the Fornax cluster: Temperature and Metallicity Distribution
Suzaku observed a central region and five offset regions within 0.2 r180 in
the Fornax cluster, a nearby poor cluster, and XMM-Newton mapped the cluster
with 15 pointings out to 0.3 r180. The distributions of O, Mg, Si, S, and Fe in
the intracluster medium (ICM) were studied with Suzaku, and those of Fe and
temperature were studied with XMM. The temperature of the ICM gradually
decreases with radius from 1.3 keV at 0.04 r180 to 1 keV at 0.2-0.3 r180. If
the new solar abundances of Lodders et al. (2003) and a single-temperature
plasma model are adopted, O, Mg, Si, S, and Fe show similar abundances: 0.4-0.6
solar within 0.02-0.2 r180. This Fe abundance is similar to those at 0.1-0.2
r180 in rich clusters and other groups of galaxies. At 0.2-0.3 r180, the Fe
abundance becomes 0.2-0.3 solar. A two-temperature plasma model yields ICM
abundances that are higher by a factor of 1.2-1.5, but gives similar abundance
ratios among O, Mg, Si, S, and Fe. The northern region has a lower ICM
temperature and higher brightness and Fe abundance, whereas the southern region
has a higher ICM temperature and lower brightness and Fe abundance. These
results indicate that the cD galaxy may have traveled from the north because of
recent dynamical evolution. The cumulative oxygen- and iron-mass-to-light
ratios within 0.3 r180 are more than an order of magnitude lower than those of
rich clusters and some relaxed groups of galaxies. Past dynamical evolution
might have hindered the strong concentration of hot gas in the Fornax cluster's
central region. Scatter in the IMLR and similarity in the element abundances in
the ICM of groups and clusters of galaxies indicate early metal synthesis.Comment: 15 pages, 13 figures, accepted for publication in PAS
The brightest UV-selected galaxies in protoclusters at : Ancestors of Brightest Cluster Galaxies?
We present the results of a survey of the brightest UV-selected galaxies in
protoclusters. These proto-brightest cluster galaxy (proto-BCG) candidates are
drawn from 179 overdense regions of -dropout galaxies at from the
Hyper Suprime-Cam Subaru Strategic Program identified previously as good
protocluster candidates. This study is the first to extend the systematic study
of the progenitors of BCGs from to . We carefully remove
possible contaminants from foreground galaxies and, for each structure, we
select the brightest galaxy that is at least 1 mag brighter than the fifth
brightest galaxy. We select 63 proto-BCG candidates and compare their
properties with those of galaxies in the field and those of other galaxies in
overdense structures. The proto-BCG candidates and their surrounding galaxies
have different rest-UV color distributions to field galaxies and
other galaxies in protoclusters that do not host proto-BCGs. In addition,
galaxies surrounding proto-BCGs are brighter than those in protoclusters
without proto-BCGs. The image stacking analysis reveals that the average
effective radius of proto-BCGs is larger than that of field
galaxies. The color differences suggest that proto-BCGs and their
surrounding galaxies are dustier than other galaxies at . These results
suggest that specific environmental effects or assembly biasses have already
emerged in some protoclusters as early as , and we suggest that
proto-BCGs have different star formation histories than other galaxies in the
same epoch.Comment: 18 pages, 11 figures, Accepted for publication in Ap
Anatomy-based prediction method for determining ipsilateral lung doses in postoperative breast radiation therapy assisted by diagnostic computed tomography images
Background: This study aimed to investigate whether ipsilateral lung doses (ILDs) could be predicted by anatomical indexes measured using diagnostic computed tomography (CT) prior to the planning stage of breast radiation therapy (RT).
Materials and methods: The thoracic diameters and the length of lines drawn manually were measured on diagnostic CT images. The parameters of interest were the skin maximum lung distance (sMLD), central lung distance (CLD), Haller index (HI), and body mass index (BMI). Lung dose-volume histograms were created with conformal planning, and the lung volumes receiving 5–40 Gy (V5–V40) were calculated. Linear regression models were used to investigate the correlations between the anatomical indexes and dose differences and to estimate the slope and 95% confidence intervals (CIs).
Results: A total of 160 patients who had undergone three-dimensional conformal RT after breast-conserving surgery were included. Univariable analysis revealed that the sMLD (p < 0.001), CLD (p < 0.001), HI (p = 0.002), and BMI (p < 0.001) were significantly correlated with the V20. However, multivariable analysis revealed that only the sMLD (slope: 0.147, p = 0.001, 95% CI: 0.162–0.306) and CLD (0.157, p = 0.005, 0.048–0.266) were strongly correlated with the V20. The p-value for the sMLD was the lowest among the p-values for all indexes, thereby indicating that the sMLD had the best predictive power for ILD.
Conclusions: sMLD and CLD are anatomical markers that can be used to predict ILD in whole breast RT. An sMLD > 20.5 mm or a CLD > 24.3 mm positively correlated with a high ILD.
SILVERRUSH. III. Deep Optical and Near-Infrared Spectroscopy for Lya and UV-Nebular Lines of Bright Lya Emitters at z=6-7
We present Lya and UV-nebular emission line properties of bright Lya emitters
(LAEs) at z=6-7 with a luminosity of log L_Lya/[erg s-1] = 43-44 identified in
the 21-deg2 area of the SILVERRUSH early sample developed with the Subaru Hyper
Suprime-Cam (HSC) survey data. Our optical spectroscopy newly confirm 21 bright
LAEs with clear Lya emission, and contribute to make a spectroscopic sample of
96 LAEs at z=6-7 in SILVERRUSH. From the spectroscopic sample, we select 7
remarkable LAEs as bright as Himiko and CR7 objects, and perform deep
Keck/MOSFIRE and Subaru/nuMOIRCS near-infrared spectroscopy reaching the
3sigma-flux limit of ~ 2x10^{-18} erg s-1 for the UV-nebular emission lines of
He II1640, C IV1548,1550, and O III]1661,1666. Except for one tentative
detection of C IV, we find no strong UV-nebular lines down to the flux limit,
placing the upper limits of the rest-frame equivalent widths (EW_0) of ~2-4 A
for He II, C IV, and O III] lines. Here we also investigate the VLT/X-SHOOTER
spectrum of CR7 whose 6 sigma detection of He II is claimed by Sobral et al.
Although two individuals and the ESO-archive service carefully re-analyze the
X-SHOOTER data that are used in the study of Sobral et al., no He II signal of
CR7 is detected, supportive of weak UV-nebular lines of the bright LAEs even
for CR7. Spectral properties of these bright LAEs are thus clearly different
from those of faint dropouts at z~7 that have strong UV-nebular lines shown in
the various studies. Comparing these bright LAEs and the faint dropouts, we
find anti-correlations between the UV-nebular line EW_0 and UV-continuum
luminosity, which are similar to those found at z~2-3.Comment: 26 pages, 12 figures. Accepted for publication in PASJ special issu
SILVERRUSH. VII. Subaru/HSC Identifications of 42 Protocluster Candidates at z~6-7 with the Spectroscopic Redshifts up to z=6.574: Implications for Cosmic Reionization
We report fourteen and twenty-eight protocluster candidates at z=5.7 and 6.6
over 14 and 19 deg^2 areas, respectively, selected from 2,230 (259) Lya
emitters (LAEs) photometrically (spectroscopically) identified with
Subaru/Hyper Suprime-Cam (HSC) deep images (Keck, Subaru, and Magellan spectra
and the literature data). Six out of the 42 protocluster candidates include
1-12 spectroscopically confirmed LAEs at redshifts up to z=6.574. By the
comparisons with the cosmological Lya radiative transfer (RT) model reproducing
LAEs with the reionization effects, we find that more than a half of these
protocluster candidates are progenitors of the present-day clusters with a mass
of > 10^14 M_sun. We then investigate the correlation between LAE overdensity
delta and Lya rest-frame equivalent width EW_Lya^rest, because the cosmological
Lya RT model suggests that a slope of EW_Lya^rest-delta relation is steepened
towards the epoch of cosmic reionization (EoR), due to the existence of the
ionized bubbles around galaxy overdensities easing the escape of Lya emission
from the partly neutral intergalactic medium (IGM). The available HSC data
suggest that the slope of the EW_Lya^rest-delta correlation does not evolve
from the post-reionization epoch z=5.7 to the EoR z=6.6 beyond the moderately
large statistical errors. There is a possibility that we would detect the
evolution of the EW_Lya^rest - delta relation from z=5.7 to 7.3 by the upcoming
HSC observations providing large samples of LAEs at z=6.6-7.3
Rib fracture after stereotactic radiotherapy on follow-up thin-section computed tomography in 177 primary lung cancer patients
<p>Abstract</p> <p>Background</p> <p>Chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer has recently been reported. However, its detailed imaging findings are not clarified. So this study aimed to fully characterize the findings on computed tomography (CT), appearance time and frequency of chest wall injury after stereotactic radiotherapy (SRT) for primary lung cancer</p> <p>Materials and methods</p> <p>A total of 177 patients who had undergone SRT were prospectively evaluated for periodical follow-up thin-section CT with special attention to chest wall injury. The time at which CT findings of chest wall injury appeared was assessed. Related clinical symptoms were also evaluated.</p> <p>Results</p> <p>Rib fracture was identified on follow-up CT in 41 patients (23.2%). Rib fractures appeared at a mean of 21.2 months after the completion of SRT (range, 4 -58 months). Chest wall edema, thinning of the cortex and osteosclerosis were findings frequently associated with, and tending to precede rib fractures. No patients with rib fracture showed tumors > 16 mm from the adjacent chest wall. Chest wall pain was seen in 18 of 177 patients (10.2%), of whom 14 patients developed rib fracture. No patients complained of Grade 3 or more symptoms.</p> <p>Conclusion</p> <p>Rib fracture is frequently seen after SRT for lung cancer on CT, and is often associated with chest wall edema, thinning of the cortex and osteosclerosis. However, related chest wall pain is less frequent and is generally mild if present.</p
First Data Release of the Hyper Suprime-Cam Subaru Strategic Program
The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered
imaging survey aimed at addressing some of the most outstanding questions in
astronomy today, including the nature of dark matter and dark energy. The
survey has been awarded 300 nights of observing time at the Subaru Telescope
and it started in March 2014. This paper presents the first public data release
of HSC-SSP. This release includes data taken in the first 1.7 years of
observations (61.5 nights) and each of the Wide, Deep, and UltraDeep layers
covers about 108, 26, and 4 square degrees down to depths of i~26.4, ~26.5, and
~27.0 mag, respectively (5sigma for point sources). All the layers are observed
in five broad bands (grizy), and the Deep and UltraDeep layers are observed in
narrow bands as well. We achieve an impressive image quality of 0.6 arcsec in
the i-band in the Wide layer. We show that we achieve 1-2 per cent PSF
photometry (rms) both internally and externally (against Pan-STARRS1), and ~10
mas and 40 mas internal and external astrometric accuracy, respectively. Both
the calibrated images and catalogs are made available to the community through
dedicated user interfaces and database servers. In addition to the pipeline
products, we also provide value-added products such as photometric redshifts
and a collection of public spectroscopic redshifts. Detailed descriptions of
all the data can be found online. The data release website is
https://hsc-release.mtk.nao.ac.jp/.Comment: 34 pages, 20 figures, 7 tables, moderate revision, accepted for
publication in PAS