270 research outputs found
Criteria Tell You More than Ratings: Criteria Preference-Aware Light Graph Convolution for Effective Multi-Criteria Recommendation
The multi-criteria (MC) recommender system, which leverages MC rating
information in a wide range of e-commerce areas, is ubiquitous nowadays.
Surprisingly, although graph neural networks (GNNs) have been widely applied to
develop various recommender systems due to GNN's high expressive capability in
learning graph representations, it has been still unexplored how to design MC
recommender systems with GNNs. In light of this, we make the first attempt
towards designing a GNN-aided MC recommender system. Specifically, rather than
straightforwardly adopting existing GNN-based recommendation methods, we devise
a novel criteria preference-aware light graph convolution CPA-LGC method, which
is capable of precisely capturing the criteria preference of users as well as
the collaborative signal in complex high-order connectivities. To this end, we
first construct an MC expansion graph that transforms user--item MC ratings
into an expanded bipartite graph to potentially learn from the collaborative
signal in MC ratings. Next, to strengthen the capability of criteria preference
awareness, CPA-LGC incorporates newly characterized embeddings, including
user-specific criteria-preference embeddings and item-specific criterion
embeddings, into our graph convolution model. Through comprehensive evaluations
using four real-world datasets, we demonstrate (a) the superiority over
benchmark MC recommendation methods and benchmark recommendation methods using
GNNs with tremendous gains, (b) the effectiveness of core components in
CPA-LGC, and (c) the computational efficiency.Comment: 12 pages, 10 figures, 5 tables; 29th ACM SIGKDD Conference on
Knowledge Discovery & Data (KDD 2023) (to appear) (Please cite our conference
version.
Hybrid waveguide from As₂S₃ and Er-doped TeO₂ for lossless nonlinear optics
The fabrication and characterization of loss-compensated dispersion-engineered nonlinear As₂S₃ on Er:TeO₂ waveguides is reported for the first time, to the best of our knowledge. The hybrid waveguide is a strip loaded structure made from an Er-doped TeO2 slab and an etched As₂S₃ strip. Almost complete loss compensation is demonstrated with 1480 nm pumping and a fully lossless waveguide with high nonlinear coefficient can be achieved with higher 1480 nm pump power.This work was supported by the Australian Research
Council under Discovery Project Grant DP0987056 and the Australian Research Council Centre of Excellence
for Ultrahigh Bandwidth Devices for Optical Systems
(project CE110001018)
Coexisting multiple dynamic states generated by magnetic field in Bi-2212 stacked Josephson junctions
Josephson vortices in naturally stacked Bi-2212 tunneling junctions display
rich dynamic behavior that derives from the coexistence of three basic states:
static Josephson vortex lattice, coherently moving lattice, and incoherent
quasiparticle tunneling state. Rich structure of hysteretic branches observed
in the current-voltage characteristics can be understood as combinatorial
combinations of these three states which are realized in different junctions
and evolve separately with magnetic field and bias current. In particular, the
multiple Josephson-vortex-flow branches at low bias currents arise from the
individual depinning of Josephson vortex rows in each junction.Comment: Submitted to Europhysics Letter
Outer membrane protein a of Salmonella enterica serovar Typhimurium activates dendritic cells and enhances Th1 polarization
<p>Abstract</p> <p>Background</p> <p>Typhoid, which is caused by <it>Salmonella enterica </it>serovar Typhimurium, remains a major health concern worldwide. Multidrug-resistant strains of <it>Salmonella </it>have emerged which exhibit increased survivability and virulence, thus leading to increased morbidity. However, little is known about the protective immune response against this microorganism. The outer membrane protein (Omp)A of bacteria plays an important role in pathogenesis.</p> <p>Results</p> <p>We purified OmpA from <it>S. enterica </it>serovar Typhimurium (OmpA-sal) and characterized the role of OmpA-sal in promoting adaptive and innate immune responses. OmpA-sal functionally activated bone marrow-derived dendritic cells by augmenting expression of CD80, CD86, and major histocompatibility complex classes I and II. Interestingly, OmpA-sal induced production of interferon-γ from T cells in mixed lymphocyte reactions, thus indicating Th1-polarizing capacity. The expression of surface markers and cytokine production in dendritic cells was mediated by the TLR4 signaling pathway in a TLR4 Knock-out system.</p> <p>Conclusions</p> <p>Our findings suggest that OmpA-sal modulates the adaptive immune responses to <it>S. enterica </it>serovar Typhimurium by activating dendritic cells and driving Th1 polarization, which are important properties to consider in the development of effective <it>S. enterica </it>serovar Typhimurium vaccines and immunotherapy adjuvant.</p
Imaging Findings of Localized Lymphoid Hyperplasia of the Pancreas: a Case Report
We report here on a case of localized lymphoid hyperplasia of the pancreas in a 70-year-old man which manifested as double lesions (uncinate process and tail) in the organ. The lesions were incidentally detected as hypoechoic lesions on ultrasonography and they appeared as delayed enhancing lesions on the contrast-enhanced dynamic CT and MRI. Total pancreatectomy was performed, because malignant tumor could not be excluded according to the preoperative imaging studies and the endoscopic ultrasound-guided biopsy failed. Pathology revealed localized lymphoid hyperplasia. The patient had an uneventful postoperative course. He has been alive for 18 months after surgery
Gate-dependent spin Hall induced nonlocal resistance and the symmetry of spin-orbit scattering in Au-clustered graphene
Engineering the electron dispersion of graphene to be spin-dependent is crucial for the realization of spin-based logic devices. Enhancing spin-orbit coupling in graphene can induce spin Hall effect, which can be adapted to generate or detect a spin current without a ferromagnet. Recently, both chemically and physically decorated graphenes have shown to exhibit large nonlocal resistance via the spin Hall and its inverse effects. However, these nonlocal transport results have raised critical debates due to the absence of field dependent Hanle curve in subsequent studies. Here, we introduce Au clusters on graphene to enhance spin-orbit coupling and employ a nonlocal geometry to study the spin Hall induced nonlocal resistance. Our results show that the nonlocal resistance highly depends on the applied gate voltage due to various current channels. However, the spin Hall induced nonlocal resistance becomes dominant at a particular carrier concentration, which is further confirmed through Hanle curves. The obtained spin Hall angle is as high as similar to 0.09 at 2 K. Temperature dependence of spin relaxation time is governed by the symmetry of spin-orbit coupling, which also depends on the gate voltage: asymmetric near the charge neutral point and symmetric at high carrier concentration. These results inspire an effective method for generating spin currents in graphene and provide important insights for the spin Hall effect as well as the symmetry of spin scattering in physically decorated graphene
Familial Creutzfeldt-Jakob Disease with V180I Mutation
Creutzfeldt-Jakob disease (CJD) is an uncommon neurodegenerative disorder with an incidence of 1 per 1000,000 per year typically characterized by rapidly progressive dementia, ataxia, myoclonus and behavioral changes. Genetic prion diseases, which develop due to a mutations in the prion protein gene (PRNP), account for an estimated 10 to 15% of all CJD cases. We report a 75-yr-old woman with familial CJD carrying a V180I mutation which features late onset, slow progression, no periodic sharp wave complexes on electroencephalography, and extensive cortical ribboning with spared the cerebellum and the medial occipital lobes posterior to the parieto-occipital sulcus on MRI. To our knowledge, this is the first documented case of a point mutation at codon 180 in South Korea
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