1,595 research outputs found
Long-term Disease-free Survival Following Combination Multi-visceral and Metastatic Resection with Neoadjuvant FOLFIRINOX for Pancreatic Adenocarcinoma: A Case Report.
We describe a case of metastatic pancreatic adenocarcinoma treated with neoadjuvant FOLFIRINOX chemotherapy and combined pancreatic multi-visceral and metastatic liver resection in a patient currently disease-free four years after diagnosis
Probing dark matter substructure in the gravitational lens HE0435-1223 with the WFC3 grism
Strong gravitational lensing provides a powerful test of Cold Dark Matter
(CDM) as it enables the detection and mass measurement of low mass haloes even
if they do not contain baryons. Compact lensed sources such as Active Galactic
Nuclei (AGN) are particularly sensitive to perturbing subhalos, but their use
as a test of CDM has been limited by the small number of systems which have
significant radio emission which is extended enough avoid significant lensing
by stars in the plane of the lens galaxy, and red enough to be minimally
affected by differential dust extinction. Narrow-line emission is a promising
alternative as it is also extended and, unlike radio, detectable in virtually
all optically selected AGN lenses. We present first results from a WFC3 grism
narrow-line survey of lensed quasars, for the quadruply lensed AGN HE0435-1223.
Using a forward modelling pipeline which enables us to robustly account for
spatial blending, we measure the [OIII] 5007 \AA~ flux ratios of the four
images. We find that the [OIII] fluxes and positions are well fit by a simple
smooth mass model for the main lens. Our data rule out a NFW perturber projected within 1\farcs0 (0\farcs1)
arcseconds of each of the lensed images, where is the perturber mass
within its central 600 pc. The non-detection is broadly consistent with the
expectations of CDM for a single system. The sensitivity achieved
demonstrates that powerful limits on the nature of dark matter can be obtained
with the analysis of narrow-line lenses.Comment: Accepted for publication in MNRAS, 15 pages, 8 figure
Neural responses to facial and vocal expressions of fear and disgust
Neuropsychological studies report more impaired responses to facial expressions of fear than disgust in people with amygdala lesions, and vice versa in people with Huntington's disease. Experiments using functional magnetic resonance imaging (fMRI) have confirmed the role of the amygdala in the response to fearful faces and have implicated the anterior insula in the response to facial expressions of disgust. We used fMRI to extend these studies to the perception of fear and disgust from both facial and vocal expressions. Consistent with neuropsychological findings, both types of fearful stimuli activated the amygdala. Facial expressions of disgust activated the anterior insula and the caudate-putamen; vocal expressions of disgust did not significantly activate either of these regions. All four types of stimuli activated the superior temporal gyrus. Our findings therefore (i) support the differential localization of the neural substrates of fear and disgust; (ii) confirm the involvement of the amygdala in the emotion of fear, whether evoked by facial or vocal expressions; (iii) confirm the involvement of the anterior insula and the striatum in reactions to facial expressions of disgust; and (iv) suggest a possible general role for the perception of emotional expressions for the superior temporal gyrus
Neural correlates of visuospatial working memory in the ‘at-risk mental state’
Background. Impaired spatial working memory (SWM) is a robust feature of schizophrenia and has been linked to
the risk of developing psychosis in people with an at-risk mental state (ARMS). We used functional magnetic
resonance imaging (fMRI) to examine the neural substrate of SWM in the ARMS and in patients who had just
developed schizophrenia.
Method. fMRI was used to study 17 patients with an ARMS, 10 patients with a first episode of psychosis and 15 agematched
healthy comparison subjects. The blood oxygen level-dependent (BOLD) response was measured while
subjects performed an object–location paired-associate memory task, with experimental manipulation of mnemonic
load.
Results. In all groups, increasing mnemonic load was associated with activation in the medial frontal and medial
posterior parietal cortex. Significant between-group differences in activation were evident in a cluster spanning the
medial frontal cortex and right precuneus, with the ARMS groups showing less activation than controls but greater
activation than first-episode psychosis (FEP) patients. These group differences were more evident at the most
demanding levels of the task than at the easy level. In all groups, task performance improved with repetition of the
conditions. However, there was a significant group difference in the response of the right precuneus across repeated
trials, with an attenuation of activation in controls but increased activation in FEP and little change in the ARMS.
Conclusions. Abnormal neural activity in the medial frontal cortex and posterior parietal cortex during an SWM task
may be a neural correlate of increased vulnerability to psychosis
Bright galaxies at Hubble's redshift detection frontier: Preliminary results and design from the redshift z~9-10 BoRG pure-parallel HST survey
We present the first results and design from the redshift z~9-10 Brightest of
the Reionizing Galaxies {\it Hubble Space Telescope} survey BoRG[z9-10], aimed
at searching for intrinsically luminous unlensed galaxies during the first 700
Myr after the Big Bang. BoRG[z9-10] is the continuation of a multi-year
pure-parallel near-IR and optical imaging campaign with the Wide Field Camera
3. The ongoing survey uses five filters, optimized for detecting the most
distant objects and offering continuous wavelength coverage from
{\lambda}=0.35{\mu}m to {\lambda}=1.7{\mu}m. We analyze the initial ~130
arcmin of area over 28 independent lines of sight (~25% of the total
planned) to search for z>7 galaxies using a combination of Lyman break and
photometric redshift selections. From an effective comoving volume of (5-25)
Mpc for magnitudes brighter than in the
-band respectively, we find five galaxy candidates at z~8.3-10
detected at high confidence (S/N>8), including a source at z~8.4 with mAB=24.5
(S/N~22), which, if confirmed, would be the brightest galaxy identified at such
early times (z>8). In addition, BoRG[z9-10] data yield four galaxies with . These new Lyman break galaxies with m are
ideal targets for follow-up observations from ground and space based
observatories to help investigate the complex interplay between dark matter
growth, galaxy assembly, and reionization.Comment: Accepted for publication on ApJ. 21 pages, 11 figures, 4 table
The KMOS^3D Survey: design, first results, and the evolution of galaxy kinematics from 0.7<z<2.7
We present the KMOS^3D survey, a new integral field survey of over 600
galaxies at 0.7<z<2.7 using KMOS at the Very Large Telescope (VLT). The KMOS^3D
survey utilizes synergies with multi-wavelength ground and space-based surveys
to trace the evolution of spatially-resolved kinematics and star formation from
a homogeneous sample over 5 Gyrs of cosmic history. Targets, drawn from a
mass-selected parent sample from the 3D-HST survey, cover the star
formation-stellar mass () and rest-frame planes uniformly. We
describe the selection of targets, the observations, and the data reduction. In
the first year of data we detect Halpha emission in 191
Msun galaxies at z=0.7-1.1 and z=1.9-2.7. In
the current sample 83% of the resolved galaxies are rotation-dominated,
determined from a continuous velocity gradient and , implying
that the star-forming 'main sequence' (MS) is primarily composed of rotating
galaxies at both redshift regimes. When considering additional stricter
criteria, the Halpha kinematic maps indicate at least ~70% of the resolved
galaxies are disk-like systems. Our high-quality KMOS data confirm the elevated
velocity dispersions reported in previous IFS studies at z>0.7. For
rotation-dominated disks, the average intrinsic velocity dispersion decreases
by a factor of two from 50 km/s at z~2.3 to 25 km/s at z~0.9 while the
rotational velocities at the two redshifts are comparable. Combined with
existing results spanning z~0-3, disk velocity dispersions follow an
approximate (1+z) evolution that is consistent with the dependence of velocity
dispersion on gas fractions predicted by marginally-stable disk theory.Comment: 20 pages, 11 figures, 1 Appendix; Accepted to ApJ November 2
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