75,239 research outputs found
Analytical Studies on the Structure and Emission of the SS433 Jets
We study the structure and emission of the SS 433 jets in the X-ray emitting
region and in the inner and hotter portion inside the X-ray emitting region. In
order to consider the jet structure from the inner to outer regions we develop
the hybrid model combining the conical beam and the model beam whose cross
section grows with the distance more slowly. We find that the jet beams in the
inner and hotter portion are of two-temperature and emit a large amount of high
energy gamma photons. Our analyses suggest the thick absorbing envelope to
exist in the SS 433 system. Based on our results, we discuss the possible
acceleration mechanism for the SS 433 jets.Comment: 15 pages. Accepted for publication by Publ. Astron. Soc. Japa
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Nasal administration of glutamate decarboxylase (GAD65) peptides induces Th2 responses and prevents murine insulin-dependent diabetes.
We previously demonstrated that a spontaneous Th1 response against glutamate decarboxylase (GAD65) arises in NOD mice at four weeks in age and subsequently T cell autoimmunity spreads both intramolecularly and intermolecularly. Induction of passive tolerance to GAD65, through inactivation of reactive T cells before the onset of autoimmunity, prevented determinant spreading and the development of insulin-dependent diabetes mellitus (IDDM). Here, we examined whether an alternative strategy, designed to induce active tolerance via the engagement of Th2 immune responses to GAD65, before the spontaneous onset of autoimmunity, could inhibit the cascade of Th1 responses that lead to IDDM. We observed that a single intranasal administration of GAD65 peptides to 2-3-wk-old NOD mice induced high levels of IgG1 antibodies to GAD65. GAD65 peptide treated mice displayed greatly reduced IFN gamma responses and increased IL-5 responses to GAD65, confirming the diversion of the spontaneous GAD65 Th1 response toward a Th2 phenotype. Consistent with the induction of an active tolerance mechanism, splenic CD4+ (but not CD8+) T cells from GAD65 peptide-treated mice, inhibited the adoptive transfer of IDDM to NOD-scid/scid mice. This active mechanism not only inhibited the development of proliferative T cell responses to GAD65, it also limited the expansion of autoreactive T cell responses to other beta cell antigens (i.e., determinant spreading). Finally, GAD65 peptide treatment reduced insulitis and long-term IDDM incidence. Collectively, these data suggest that the nasal administration of GAD65 peptides induces a Th2 cell response that inhibits the spontaneous development of autoreactive Th1 responses and the progression of beta cell autoimmunity in NOD mice
Next-to-leading order QCD corrections to Higgs boson production in association with a photon via weak-boson fusion at the LHC
Higgs boson production in association with a hard central photon and two
forward tagging jets is expected to provide valuable information on Higgs boson
couplings in a range where it is difficult to disentangle weak-boson fusion
processes from large QCD backgrounds. We present next-to-leading order QCD
corrections to Higgs production in association with a photon via weak-boson
fusion at a hadron collider in the form of a flexible parton-level Monte Carlo
program. The QCD corrections to integrated cross sections are found to be small
for experimentally relevant selection cuts, while the shape of kinematic
distributions can be distorted by up to 20% in some regions of phase space.
Residual scale uncertainties at next-to-leading order are at the few-percent
level.Comment: 17 pages, 7 figures, 1 tabl
Men Are from Mars, Women Are from Venus: Evaluation and Modelling of Verbal Associations
We present a quantitative analysis of human word association pairs and study
the types of relations presented in the associations. We put our main focus on
the correlation between response types and respondent characteristics such as
occupation and gender by contrasting syntagmatic and paradigmatic associations.
Finally, we propose a personalised distributed word association model and show
the importance of incorporating demographic factors into the models commonly
used in natural language processing.Comment: AIST 2017 camera-read
Analysing multiparticle quantum states
The analysis of multiparticle quantum states is a central problem in quantum
information processing. This task poses several challenges for experimenters
and theoreticians. We give an overview over current problems and possible
solutions concerning systematic errors of quantum devices, the reconstruction
of quantum states, and the analysis of correlations and complexity in
multiparticle density matrices.Comment: 20 pages, 4 figures, prepared for proceedings of the "Quantum
[Un]speakables II" conference (Vienna, 2014
NLO Higgs boson production via vector-boson fusion matched with shower in POWHEG
We present a next-to-leading order calculation of Higgs boson production in
vector-boson fusion processes interfaced to shower Monte Carlo programs,
implemented according to the POWHEG method.Comment: 16 pages, 9 figures. A few references and a new figure adde
Interacting fermions and N=2 Chern-Simons-matter theories
The partition function on the three-sphere of N=3 Chern-Simons-matter
theories can be formulated in terms of an ideal Fermi gas. In this paper we
show that, in theories with N=2 supersymmetry, the partition function
corresponds to a gas of interacting fermions in one dimension. The large N
limit is the thermodynamic limit of the gas and it can be analyzed with the
Hartree and Thomas-Fermi approximations, which lead to the known large N
solutions of these models. We use this interacting fermion picture to analyze
in detail N=2 theories with one single node. In the case of theories with no
long-range forces we incorporate exchange effects and argue that the partition
function is given by an Airy function, as in N=3 theories. For the theory with
g adjoint superfields and long-range forces, the Thomas-Fermi approximation
leads to an integral equation which determines the large N, strongly coupled
R-charge.Comment: 29 pages, 4 figure
Activity in the human superior colliculus relating to endogenous saccade preparation and execution
In recent years a small number of studies have applied functional imaging techniques to investigate visual responses in the human superior colliculus (SC), but few have investigated its oculomotor functions. Here, in two experiments, we examined activity associated with endogenous saccade preparation. We used 3-T fMRI to record the hemodynamic activity in the SC while participants were either preparing or executing saccadic eye movements. Our results showed that not only executing a saccade (as previously shown) but also preparing a saccade produced an increase in the SC hemodynamic activity. The saccade-related activity was observed in the contralateral and to a lesser extent the ipsilateral SC. A second experiment further examined the contralateral mapping of saccade-related activity with a larger range of saccade amplitudes. Increased activity was again observed in both the contralateral and ipsilateral SC that was evident for large as well as small saccades. This suggests that the ipsilateral component of the increase in BOLD is not due simply to small-amplitude saccades producing bilateral activity in the foveal fixation zone. These studies provide the first evidence of presaccadic preparatory activity in the human SC and reveal that fMRI can detect activity consistent with that of buildup neurons found in the deeper layers of the SC in studies of nonhuman primates
Learning Visual Question Answering by Bootstrapping Hard Attention
Attention mechanisms in biological perception are thought to select subsets
of perceptual information for more sophisticated processing which would be
prohibitive to perform on all sensory inputs. In computer vision, however,
there has been relatively little exploration of hard attention, where some
information is selectively ignored, in spite of the success of soft attention,
where information is re-weighted and aggregated, but never filtered out. Here,
we introduce a new approach for hard attention and find it achieves very
competitive performance on a recently-released visual question answering
datasets, equalling and in some cases surpassing similar soft attention
architectures while entirely ignoring some features. Even though the hard
attention mechanism is thought to be non-differentiable, we found that the
feature magnitudes correlate with semantic relevance, and provide a useful
signal for our mechanism's attentional selection criterion. Because hard
attention selects important features of the input information, it can also be
more efficient than analogous soft attention mechanisms. This is especially
important for recent approaches that use non-local pairwise operations, whereby
computational and memory costs are quadratic in the size of the set of
features.Comment: ECCV 201
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