2,800 research outputs found
Relativistic spin precession in the binary PSR J11416545
PSR J11416545 is a precessing binary pulsar that has the rare potential to
reveal the two-dimensional structure of a non-recycled pulsar emission cone. It
has undergone of relativistic spin precession in the
years since its discovery. In this paper, we present a detailed Bayesian
analysis of the precessional evolution of the width of the total intensity
profile, to understand the changes to the line-of-sight impact angle ()
of the pulsar using four different physically motivated prior distribution
models. Although we cannot statistically differentiate between the models with
confidence, the temporal evolution of the linear and circular polarisations
strongly argue that our line-of-sight crossed the magnetic pole around MJD
54000 and that only two models remain viable. For both these models, it appears
likely that the pulsar will precess out of our line-of-sight in the next
years, assuming a simple beam geometry. Marginalising over suggests
that the pulsar is a near-orthogonal rotator and provides the first
polarization-independent estimate of the scale factor () that
relates the pulsar beam opening angle () to its rotational period ()
as : we find it to be at 1.4
GHz with 99\% confidence. If all pulsars emit from opposite poles of a dipolar
magnetic field with comparable brightness, we might expect to see evidence of
an interpulse arising in PSR J11416545, unless the emission is patchy.Comment: Accepted for publication in Astrophysical Journal Letter
Predictive-State Decoders: Encoding the Future into Recurrent Networks
Recurrent neural networks (RNNs) are a vital modeling technique that rely on
internal states learned indirectly by optimization of a supervised,
unsupervised, or reinforcement training loss. RNNs are used to model dynamic
processes that are characterized by underlying latent states whose form is
often unknown, precluding its analytic representation inside an RNN. In the
Predictive-State Representation (PSR) literature, latent state processes are
modeled by an internal state representation that directly models the
distribution of future observations, and most recent work in this area has
relied on explicitly representing and targeting sufficient statistics of this
probability distribution. We seek to combine the advantages of RNNs and PSRs by
augmenting existing state-of-the-art recurrent neural networks with
Predictive-State Decoders (PSDs), which add supervision to the network's
internal state representation to target predicting future observations.
Predictive-State Decoders are simple to implement and easily incorporated into
existing training pipelines via additional loss regularization. We demonstrate
the effectiveness of PSDs with experimental results in three different domains:
probabilistic filtering, Imitation Learning, and Reinforcement Learning. In
each, our method improves statistical performance of state-of-the-art recurrent
baselines and does so with fewer iterations and less data.Comment: NIPS 201
Morphometry of the Dugong Dugon (Muller, 1776) skeleton based on Indian Museum specimens, Kolkata, India
817-821The present study discussed about detailed examination of skeleton characters of four dugong specimens received from Indian Museum. The specimens were deposited and preserved in the National Zoological Collection (ZSI/27608; ZSI/27609; ZSI/27610; ZSI/27611) of The Mammal and Osteological Section, Zoological Survey of India, Kolkata
Clinicopathological Features of Cutaneous Lymphomas and T-Cell Receptor Gamma Gene Rearrangement Studies in Early Stage Mycosis Fungoides
OBJECTIVE:
To study the clinicopathological features of cutaneous lymphomas and the role of TCR gene rearrangement in the diagnosis ofpatch/plaque (Stage I/IIA) mycosis fungoides where the histological diagnosis of mycosis fungoides could not be excluded or the diagnosis was suggestive but not confirmatory.
METHOD:
Ahospital based cross sectional study was conducted from November 2012 to August 2014 where in patients with a diagnosis of cutaneous lymphoma (CL) were included. Diagnosis was established by histology and immunohistochemistry and classified based on WHO-EORTC classification. TCR gamma gene rearrangement assay was done by PCR in patch/plaque (Stage I/IIA) mycosis fungoides (MF) where the histological diagnosis of mycosis fungoides could not be excluded or the diagnosis was suggestive but not confirmatory. Routine laboratory tests; lymph node, bone marrow biopsies and imaging were done when indicated for staging based on the ISCL/EORTC proposal.
RESULTS:
There were 54 patients (M/F-1.25) with CL.This included primary cutaneous T-cell lymphomas (CTCL) (48), secondary CTCL (4), primary cutaneous B-cell lymphoma (CBCL) (1) and secondary CBCL (1). Among CTCL there were 27 cases of MF, LyP (lymphomatoid papulosis) (8), SPTL (subcutaneous panniculitis like T-cell lymphoma) (6), ALCL (Anaplastic large cell lymphoma) (3), PTCL, NOS (peripheral T-cell lymphoma, not otherwise specified) (3) and HVLL (hydroa vacciniforme like T-cell lymphoma) (1). Mean age at diagnosis of MF, CD30+ LPD, SPTL and PTCL, NOS were 41.1±18.8 years, 33.8±17.1 years, 33.6±17.3 years and 56.3±18.9 years respectively.Paediatric CL accounted for 16.7% of cases. The most common type of CTCL in the paediatric age group (≤20 years) was MF (n=4, 44.4%) followed by LyP (n=2, 22.2%), SPTL (n=2, 22.2%) and HVLL (n=1, 11.1%). Male preponderance was noted in all subtypes of cutaneous lymphoma except SPTL. Unusual clinical types of MF in our study included hypopigmented MF and dyshidrosiform MF. MF with palmoplantar involvement was seen in 14.8% patients. Among the unusual types of CTCL (other than MF) seen in our study were one case each of erythrodermic ALCL, LyP type D and HVLL. Clonality detection rate among early stage MF in our study was 61.5%. Statistical significance of clonal detection with histological grading and immunohistochemistry findings was not found in our study.
CONCLUSION:
CTCL was the most common subtype as reported in earlier studies from Asian countries and the West. However the proportion of CBCL was lower than that reported from other countries. Female preponderance was noted in SPTL and rest of the subtypes showed a male preponderance.MF was the commonest among CTCL comprising 56.25% of all CTCLs. Monoclonality detection in early stage MF was slightly lower than the detection rate in various studies across Europe using a similar protocol. Though the statistical significance of clonality detection with histopathological grading of MF could not be demonstrated it was evident that in patients with histopathological diagnosis suggestive of MF had increased clonal detection rate.Usefulness of TCR clonal rearrangement studies in early MF has to be further evaluated with large population studies
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