651 research outputs found
EvolveGCN: Evolving Graph Convolutional Networks for Dynamic Graphs
Graph representation learning resurges as a trending research subject owing
to the widespread use of deep learning for Euclidean data, which inspire
various creative designs of neural networks in the non-Euclidean domain,
particularly graphs. With the success of these graph neural networks (GNN) in
the static setting, we approach further practical scenarios where the graph
dynamically evolves. Existing approaches typically resort to node embeddings
and use a recurrent neural network (RNN, broadly speaking) to regulate the
embeddings and learn the temporal dynamics. These methods require the knowledge
of a node in the full time span (including both training and testing) and are
less applicable to the frequent change of the node set. In some extreme
scenarios, the node sets at different time steps may completely differ. To
resolve this challenge, we propose EvolveGCN, which adapts the graph
convolutional network (GCN) model along the temporal dimension without
resorting to node embeddings. The proposed approach captures the dynamism of
the graph sequence through using an RNN to evolve the GCN parameters. Two
architectures are considered for the parameter evolution. We evaluate the
proposed approach on tasks including link prediction, edge classification, and
node classification. The experimental results indicate a generally higher
performance of EvolveGCN compared with related approaches. The code is
available at \url{https://github.com/IBM/EvolveGCN}.Comment: AAAI 2020. The code is available at https://github.com/IBM/EvolveGC
Loss of PTEN expression is associated with colorectal cancer liver metastasis and poor patient survival
A Transponder Aggregator with Efficient Use of Filtering Function for Transponder Noise Suppression
Colorless, directionless, and contentionless reconfigurable optical add/drop
multiplexing (CDC-ROADM) provides highly flexible physical layer network
configuration. Such CDC-ROADM must operate in multiple wavelength bands which
are being increasingly implemented in optical transmission systems. The
operation in C+L bands requires switch devices used in CDC-ROADM to also be
capable of multiband operation. Recent studies on wavelength division
multiplexing (WDM) systems have pointed out the impact of amplified spontaneous
emission (ASE) noise generated by signals of different wavelengths, which
causes OSNR degradation. Therefore, it is desirable to filter out the ASE noise
from different transponders when multiplexing multiple wavelengths at the
transmitter side, especially in a system with non-wavelength selective
combiners such as directional couplers and multicast switches. The use of
transponder aggregators with filtering functions, such as the M x N wavelength
selective switch (WSS), is preferable for this filtering. However, the downside
of these devices is that it is difficult to provide economical multiband
support. Therefore, we propose an economical transponder aggregator
configuration by allowing a certain amount of ASE superposition and reducing
the number of filtering functions. In this paper, we fabricated a prototype of
the proposed transponder aggregator by combining silica-based planar lightwave
circuit technology and C+L band WSS, both commercially available, and verified
its feasibility through transmission experiments. The novel transponder
aggregator is a practical solution for a multiband CDC-ROADM system with
improved OSNR performance.Comment: 10 pages, 11 figures. Submitted to IEEE Journal of Lightwave
Technology for possible publicatio
Activation of focal adhesion kinase via M1 muscarinic acetylcholine receptor is required in restitution of intestinal barrier function after epithelial injury
AbstractImpairment of epithelial barrier is observed in various intestinal disorders including inflammatory bowel diseases (IBD). Numerous factors may cause temporary damage of the intestinal epithelium. A complex network of highly divergent factors regulates healing of the epithelium to prevent inflammatory response. However, the exact repair mechanisms involved in maintaining homeostatic intestinal barrier integrity remain to be clarified.In this study, we demonstrate that activation of M1 muscarinic acetylcholine receptor (mAChR) augments the restitution of epithelial barrier function in T84 cell monolayers after ethanol-induced epithelial injury, via ERK-dependent phosphorylation of focal adhesion kinase (FAK). We have shown that ethanol injury decreased the transepithelial electrical resistance (TER) along with the reduction of ERK and FAK phosphorylation. Carbachol (CCh) increased ERK and FAK phosphorylation with enhanced TER recovery, which was completely blocked by either MT-7 (M1 antagonist) or atropine. The CCh-induced enhancement of TER recovery was also blocked by either U0126 (ERK pathway inhibitor) or PF-228 (FAK inhibitor). Treatment of T84 cell monolayers with interferon-γ (IFN-γ) impaired the barrier function with the reduction of FAK phosphorylation. The CCh-induced ERK and FAK phosphorylation were also attenuated by the IFN-γ treatment. Immunological and binding experiments exhibited a significant reduction of M1 mAChR after IFN-γ treatment. The reduction of M1 mAChR in inflammatory area was also observed in surgical specimens from IBD patients, using immunohistochemical analysis. These findings provide important clues regarding mechanisms by which M1 mAChR participates in the maintenance of intestinal barrier function under not only physiological but also pathological conditions
The management of imaging dose during imageâ guided radiotherapy: Report of the AAPM Task Group 75
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134823/1/mp5667.pd
Evolution of tetragonal phase in the FeSe wire fabricated by a novel chemical-transformation PIT process
We fabricated superconducting FeSe wires by the chemical-transformation PIT
process. The obvious correlation between annealing temperature and phase
transformation was observed. Annealing above 500^{\circ}C produced wire-core
transformation from hexagonal to tetragonal phase. Furthermore the hexagonal
phase completely transformed into the tetragonal phase by annealing at
1000^{\circ}C. With increasing annealing temperature, the superconducting
property was dramatically improved, associated with the evolution of the
tetragonal phase.Comment: 14 pages, 6 figure
Evaluation of persistent-mode operation in a superconducting MgB2 coil in solid nitrogen
We report the fabrication of a magnesium diboride (MgB2) coil and evaluate its persistent-mode operation in a system cooled by a cryocooler with solid nitrogen (SN2) as a cooling medium. The main purpose of SN2 was to increase enthalpy of the cold mass. For this work, an in situ processed carbon-doped MgB2 wire was used. The coil was wound on a stainless steel former in a single layer (22 turns), with an inner diameter of 109 mm and height of 20 mm without any insulation. The two ends of the coil were then joined to make a persistent-current switch to obtain the persistent-current mode. After a heat treatment, the whole coil was installed in the SN2 chamber. During operation, the resultant total circuit resistance was estimated to be \u3c7.4x10−14 Ω at 19.5 K±1.5 K, which meets the technical requirement for magnetic resonance imaging application
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