Hy-DeFake: Hypergraph Neural Networks for Detecting Fake News in Online Social Networks

Nowadays social media is the primary platform for people to obtain news and share information. Combating online fake news has become an urgent task to reduce the damage it causes to society. Existing methods typically improve their fake news detection performances by utilizing textual auxiliary information (such as relevant retweets and comments) or simple structural information (i.e., graph construction). However, these methods face two challenges. First, an increasing number of users tend to directly forward the source news without adding comments, resulting in a lack of textual auxiliary information. Second, simple graphs are unable to extract complex relations beyond pairwise association in a social context. Given that real-world social networks are intricate and involve high-order relations, we argue that exploring beyond pairwise relations between news and users is crucial for fake news detection. Therefore, we propose constructing an attributed hypergraph to represent non-textual and high-order relations for user participation in news spreading. We also introduce a hypergraph neural network-based method called Hy-DeFake to overcome the challenges. Our proposed method captures semantic information from news content, credibility information from involved users, and high-order correlations between news and users to learn distinctive embeddings for fake news detection. The superiority of Hy-DeFake is demonstrated through experiments conducted on four widely-used datasets, and it is compared against six baselines using four evaluation metrics

The Effect of Substituent on Molecules That Contain a Triple Bond Between Arsenic and Group 13 Elements: Theoretical Designs and Characterizations

The effect of substitution on the potential energy surfaces of RE13≡AsR (E13 = group 13 elements; R = F, OH, H, CH3, and SiH3) is determined using density functional theory (M06‐2X/Def2‐TZVP, B3PW91/Def2‐TZVP, and B3LYP/LANL2DZ+dp). The computational studies demonstrate that all triply bonded RE13≡AsR species prefer to adopt a bent geometry that is consistent with the valence electron model. The theoretical studies also demonstrate that RE13≡AsR molecules with smaller substituents are kinetically unstable, with respect to the intramolecular rearrangements. However, triply bonded R′E13≡AsR′ species with bulkier substituents (R′ = SiMe(SitBu3)2, SiiPrDis2, and NHC) are found to occupy the lowest minimum on the singlet potential energy surface, and they are both kinetically and thermodynamically stable. That is to say, the electronic and steric effects of bulky substituents play an important role in making molecules that feature an E13≡As triple bond as viable synthetic target

Triple Bonds between Bismuth and Group 13 Elements: Theoretical Designs and Characterization

The effect of substitution on the potential energy surfaces of RE13≡BiR (E13 = B, Al, Ga, In, and Tl; R = F, OH, H, CH3, SiH3, Tbt, Ar*, SiMe(SitBu3)2, and SiiPrDis2) is investigated using density functional theories (M06-2X/Def2-TZVP, B3PW91/Def2-TZVP, and B3LYP/LANL2DZ+dp). The theoretical results suggest that all of the triply bonded RE13≡BiR molecules prefer to adopt a bent geometry (i.e., ∠RE13Bi ≈ 180° and ∠E13BiR ≈ 90°), which agrees well with the bonding model (model (B)). It is also demonstrated that the smaller groups, such as R = F, OH, H, CH3, and SiH3, neither kinetically nor thermodynamically stabilize the triply bonded RE13≡BiR compounds, except for the case of H3SiB≡BiSiH3. Nevertheless, the triply bonded RʹE13≡BiRʹ molecules that feature bulkier substituents (Rʹ = Tbt, Ar*, SiMe(SitBu3)2, and SiiPrDis2) are found to have the global minimum on the singlet potential energy surface and are both kinetically and thermodynamically stable. In other words, both the electronic and the steric effects of bulkier substituent groups play an important role in making triply bonded RE13≡BiR (Group 13–Group 15) species synthetically accessible and isolable in a stable form

Exotic Superconducting Properties in Topological Nodal Semimetal PbTaSe2_2

We report the electronic properties of superconductivity in the topological nodal-line semimetal PbTaSe$_2$. Angle-resolved photoemission measurements accompanied by band calculations confirmed the nodal-line band structure in the normal state of single crystalline PbTaSe$_2$. Resistivity, magnetic-susceptibility and specific heat measurements have also been performed on high-quality single crystals. We observed upward features and large anisotropy in upper critical field ($H_{c2}$) measured in-plane (H//\textbf{ab}) and out-plane (H//\textbf{c}), respectively. Especially, $H_{c2}$ measured in H//\textbf{ab} shows sudden upward features rather than a signal of saturation in ultralow temperatures. The specific heat measurements under magnetic field reveal a full superconducting gap with no gapless nodes. These behaviors in this clean noncentrosymmetric superconductor is possibly related to the underlying exotic physics, providing important clue for realization of topological superconductivity.Comment: 6 pages, 5 figures,1 table;Accepted for publication on PR

The Triply Bonded Al☰Sb Molecules: A Theoretical Prediction

The effect of substitution on the potential energy surfaces of RAl☰SbR (R = F, OH, H, CH3, SiH3, SiMe(SitBu3)2, SiiPrDis2, Tbt, and Ar*) is investigated using density functional theories (M06-2X/Def2-TZVP, B3PW91/Def2-TZVP, and B3LYP/LANL2DZ + dp). The theoretical results demonstrated that all the triply bonded RAl☰SbR compounds with small substituents are unstable and can spontaneously rearrange to other doubly bonded isomers. That is, the smaller groups, such as R = F, OH, H, CH3 and SiH3, neither kinetically nor thermodynamically stabilize the triply bonded RAl☰SbR compounds. However, the triply bonded R’Al☰SbR´ molecules that feature bulkier substituents (R´ = SiMe(SitBu3)2, SiiPrDis2, Tbt, and Ar*) are found to possess the global minimum on the singlet potential energy surface and are both kinetically and thermodynamically stable. In particular, the bonding characters of the R’Al☰SbR´ species agree well with the valence-electron bonding model (model) as well as several theoretical analyses (the natural bond orbital, the natural resonance theory, and the charge decomposition analysis). That is to say, R’Al☰SbR´ molecules that feature groups are regarded as R′─Al Sb─R′. Their theoretical evidence shows that both the electronic and the steric effects of bulkier substituent groups play a decisive role in making triply bonded R′Al☰SbR′ species synthetically accessible and isolable in a stable form

Simulations Suggest Possible Triply Bonded Phosphorus≡E13 Molecules (E13 = B, Al, Ga, In, and Tl)

The effect of substitution on the potential energy surfaces of RE13 ☰ PR (E13 = B, Al, Ga, In, Tl; R = F, OH, H, CH3, SiH3, SiMe(SitBu3)2, SiiPrDis2, Tbt, and Ar* is studied using density functional theory (M06-2X/Def2-TZVP, B3PW91/Def2-TZVP and B3LYP/LANL2DZ + dp). The theoretical results demonstrate that all triply bonded RE13 ☰ PR compounds with small substituents are unstable and spontaneously rearrange to other doubly bonded isomers. That is, the smaller groups, such as R 〓 F, OH, H, CH3 and SiH3, neither kinetically nor thermodynamically stabilize the triply bonded RE13 ☰ PR compounds. However, the triply bonded R’E13☰PR´ molecules, possessing bulkier substituents (R´ = SiMe(SitBu3)2, SiiPrDis2, Tbt and Ar*), are found to have a global minimum on the singlet potential energy surface. In particular, the bonding character of the R’E13☰PR´ species is well defined by the valence-electron bonding model (model [II]). That is to say, R’E13☰PR´ molecules that feature groups are regarded as R′-E13P-R′. The theoretical evidence shows that both the electronic and the steric effects of bulkier substituent groups play a prominent role in rendering triply bonded R′E13☰PR′ species synthetically accessible and isolable in a stable form