9,691 research outputs found
MedTruth: A Semi-supervised Approach to Discovering Knowledge Condition Information from Multi-Source Medical Data
Knowledge Graph (KG) contains entities and the relations between entities.
Due to its representation ability, KG has been successfully applied to support
many medical/healthcare tasks. However, in the medical domain, knowledge holds
under certain conditions. For example, symptom \emph{runny nose} highly
indicates the existence of disease \emph{whooping cough} when the patient is a
baby rather than the people at other ages. Such conditions for medical
knowledge are crucial for decision-making in various medical applications,
which is missing in existing medical KGs. In this paper, we aim to discovery
medical knowledge conditions from texts to enrich KGs.
Electronic Medical Records (EMRs) are systematized collection of clinical
data and contain detailed information about patients, thus EMRs can be a good
resource to discover medical knowledge conditions. Unfortunately, the amount of
available EMRs is limited due to reasons such as regularization. Meanwhile, a
large amount of medical question answering (QA) data is available, which can
greatly help the studied task. However, the quality of medical QA data is quite
diverse, which may degrade the quality of the discovered medical knowledge
conditions. In the light of these challenges, we propose a new truth discovery
method, MedTruth, for medical knowledge condition discovery, which incorporates
prior source quality information into the source reliability estimation
procedure, and also utilizes the knowledge triple information for trustworthy
information computation. We conduct series of experiments on real-world medical
datasets to demonstrate that the proposed method can discover meaningful and
accurate conditions for medical knowledge by leveraging both EMR and QA data.
Further, the proposed method is tested on synthetic datasets to validate its
effectiveness under various scenarios.Comment: Accepted as CIKM2019 long pape
Poly[di-μ2-azido-μ3-pyrazine-2-carboxylÂato-cadmium(II)]
The title compound, [Cd(C5H3N2O2)(N3)]n, has been preÂpared by the reaction of pyrazine-2-carboxylic acid, cadmium(II) nitrate and sodium azide. In the structure, the CdII atom is six-coordinated by two azide anions and three pyrazine-2-carboxylÂate ligands. Each pyrazine-2-carboxylÂate ligand bridges three CdII atoms, whereas the azide ligand bridges two CdII atoms, resulting in the formation of a two-dimensional metal–organic polymer developing parallel to the (100) plane
Millimeter Spectral Line Mapping Observations Toward Four Massive Star Forming HII Regions
We present spectral line mapping observations toward four massive
star-forming regions (Cepheus A, DR21S, S76E and G34.26+0.15), with the IRAM 30
meter telescope at 2 mm and 3 mm bands. Totally 396 spectral lines from 51
molecules, one helium recombination line, ten hydrogen recombination lines, and
16 unidentified lines were detected in these four sources. An emission line of
nitrosyl cyanide (ONCN, 14-13) was detected in G34.26+0.15,
as first detection in massive star-forming regions. We found that the
-CH and NHD show enhancement in shocked regions as
suggested by evidences of SiO and/or SO emission. Column density and rotational
temperature of CHCN were estimated with the rotational diagram method for
all four sources. Isotope abundance ratios of C/C were derived
using HCN and its C isotopologue, which were around 40 in all four
massive star-forming regions and slightly lower than the local interstellar
value (65). N/N and O/O abundance ratios in
these sources were also derived using double isotopic method, which were
slightly lower than that in local interstellar medium. Except for Cep A,
S/S ratio in the other three targets were derived, which were
similar to that in the local interstellar medium. The column density ratios of
N(DCN)/N(HCN) and N(DCO)/N(HCO) in these sources were more than two
orders of magnitude higher than the elemental [D]/[H] ratio, which is
1.510. Our results show the later stage sources, G34.26+0.15 in
particular, present more molecular species than earlier stage ones. Evidence of
shock activity is seen in all stages studied.Comment: 32 pages, 11 figures, 8 tables, accepted for publication in MNRA
Joint Location Sensing and Channel Estimation for IRS-Aided mmWave ISAC Systems
In this paper, we investigate a self-sensing intelligent reflecting surface
(IRS) aided millimeter wave (mmWave) integrated sensing and communication
(ISAC) system. Unlike the conventional purely passive IRS, the self-sensing IRS
can effectively reduce the path loss of sensing-related links, thus rendering
it advantageous in ISAC systems. Aiming to jointly sense the
target/scatterer/user positions as well as estimate the sensing and
communication (SAC) channels in the considered system, we propose a two-phase
transmission scheme, where the coarse and refined sensing/channel estimation
(CE) results are respectively obtained in the first phase (using scanning-based
IRS reflection coefficients) and second phase (using optimized IRS reflection
coefficients). For each phase, an angle-based sensing turbo variational
Bayesian inference (AS-TVBI) algorithm, which combines the VBI, messaging
passing and expectation-maximization (EM) methods, is developed to solve the
considered joint location sensing and CE problem. The proposed algorithm
effectively exploits the partial overlapping structured (POS) sparsity and
2-dimensional (2D) block sparsity inherent in the SAC channels to enhance the
overall performance. Based on the estimation results from the first phase, we
formulate a Cram\'{e}r-Rao bound (CRB) minimization problem for optimizing IRS
reflection coefficients, and through proper reformulations, a low-complexity
manifold-based optimization algorithm is proposed to solve this problem.
Simulation results are provided to verify the superiority of the proposed
transmission scheme and associated algorithms
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