Maximizing External Action with Information Provision over Multiple Rounds in Online Social Networks

Online social networks have increased their impact on the real world, which motivates information senders to control the propagation process of information to promote particular actions of online users. However, the existing works on information provisioning seem to oversimplify the users? decision-making process that involves information reception, internal actions of social networks, and external actions of social networks. In particular, characterizing the best practices of information provisioning that promotes the users? external actions is a complex task due to the complexity of the propagation process in OSNs, even when the variation of information is limited. Therefore, we propose a new information diffusion model that distinguishes user behaviors inside and outside of OSNs, and formulate an optimization problem to maximize the number of users who take the external actions by providing information over multiple rounds. Also, we define a robust provisioning policy for the problem, which selects a message sequence to maximize the expected number of desired users under the probabilistic uncertainty of OSN settings. Our experiment results infer that there could exist an information provisioning policy that achieves nearly-optimal solutions in different types of OSNs. Furthermore, we empirically demonstrate that the proposed robust policy can be such a universally optimal solution

Complementary analysis of trace elements in nail samples using instrumental neutron activation analysis and inductively coupled plasma mass spectrometry

Instrumental neutron activation analysis (INAA) and inductively coupled plasma-mass spectrometry (ICPMS) were applied to determine minor and trace elements in human nail samples. Validation of each method was performed by measuring NIES No. 5 Human Hair certiˆed reference material. Good agreements were observed between certiˆed and measured values for these methods. Nail samples collected from 18 healthy volunteers were washed, dried and cut into small pieces. The samples were divided into two portions, one of which was analyzed by INAA and the other by ICPMS. In INAA, Na, Mg, Al, Cl, K, Ca, V, Mn and Cu were recognized and the concentrations of these elements were calculated. On the other hand, peaks of Cu, Zn, Sr,Ag, Sn, Sb, Ba,CeHg and Pb were observed in the spectrum by ICPMS. Copper, Zn, Sr, Ag and Pb were determined by ICPMS because these elements showed su‹ciently high intensity without spectrum interference. Nine and ˆve elements were determined by INAA and ICPMS. Copper was determined by both methods, and good correlation was observed. Combination of INAA and ICPMS has an advantage to provide more information of elemental contents for nail samples if more than only one of the two methods is employed

Fermi surface reconstruction due to the orthorhombic distortion in Dirac semimetal YbMnSb2_2

Dirac semi-metal with magnetic atoms as constituents delivers an interesting platform to investigate the interplay of Fermi surface (FS) topology, electron correlation, and magnetism. One such family of semi-metal is YbMn$Pn_2$ ($Pn$ = Sb, Bi), which is being actively studied due to the intertwined spin and charge degrees of freedom. In this Letter, we investigate the relationship between the magnetic/crystal structures and FS topology of YbMnSb$_2$ using single crystal x-ray diffraction, neutron scattering, magnetic susceptibility, magnetotransport measurement and complimentary DFT calculation. Contrary to previous reports, the x-ray and neutron diffraction reveal that YbMnSb$_2$ crystallizes in an orthorhombic $Pnma$ structure with notable anti-phase displacement of the magnetic Mn ions that increases in magnitude upon cooling. First principles DFT calculation reveals a reduced Brillouin zone and more anisotropic FS of YbMnSb$_2$ compared to YbMnBi$_2$ as a result of the orthorhombicity. Moreover, the hole type carrier density drops by two orders of magnitude as YbMnSb$_2$ orders antiferromagnetically indicating band folding in magnetic ordered state. In addition, the Landau level fan diagram yields a non-trivial nature of the SdH quantum oscillation frequency arising from the Dirac-like Fermi pocket. These results imply that YbMnSb$_2$ is an ideal platform to explore the interplay of subtle lattice distortion, magnetic order, and topological transport arising from relativistic quasiparticles.Comment: 11 pages, contains 4 figures and 7 Supplemental Figure

Prophylactic Instillation of Hydrogen-Rich Water Decreases Corneal Inflammation and Promotes Wound Healing by Activating Antioxidant Activity in a Rat Alkali Burn Model

Many studies have demonstrated the therapeutic effects of hydrogen in pathological conditions such as inflammation; however, little is known about its prophylactic effects. The purpose of this study is to investigate the prophylactic effects of hydrogen-rich water instillation in a rat corneal alkali burn model. Hydrogen-rich water (hydrogen group) or physiological saline (vehicle group) was instilled continuously to the normal rat cornea for 5 min. At 6 h after instillation, the cornea was exposed to alkali. The area of corneal epithelial defect (CED) was measured every 6 h until 24 h after alkali exposure. In addition, at 6 and 24 h after injury, histological and immunohistochemical observations were made and real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to investigate superoxide dismutase enzyme (SOD)1, SOD2, and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) mRNA expression. CED at 12 h and the number of inflammatory infiltrating cells at 6 h after injury were significantly smaller in the hydrogen group than the vehicle group. Furthermore, SOD1 expression was significantly higher in the hydrogen group than the vehicle group at both 6 and 24 h, and the number of PGC-1α-positive cells was significantly larger in the hydrogen group than the vehicle group at 6 h after injury. In this model, prophylactic instillation of hydrogen-rich water suppressed alkali burn-induced inflammation, likely by upregulating expression of antioxidants such as SOD1 and PGC-1α. Hydrogen has not only therapeutic potential but also prophylactic effects that may suppress corneal scarring following injury and promote wound healing

Disulfiram Ophthalmic Solution Inhibited Macrophage Infiltration by Suppressing Macrophage Pseudopodia Formation in a Rat Corneal Alkali Burn Model

FROUNT is an intracellular protein that promotes pseudopodia formation by binding to the chemokine receptors CCR2 and CCR5 on macrophages. Recently, disulfiram (DSF), a drug treatment for alcoholism, was found to have FROUNT inhibitory activity. In this study, we investigated the effect of DSF eye drops in a rat corneal alkali burn model. After alkali burn, 0.5% DSF eye drops (DSF group) and vehicle eye drops (Vehicle group) were administered twice daily. Immunohistochemical observations and real-time reverse transcription-polymerase chain reaction (RT-PCR) analyses were performed at 6 h and 1, 4, and 7 days after alkali burn. Results showed a significant decrease in macrophage accumulation in the cornea in the DSF group, but no difference in neutrophils. RT-PCR showed decreased expression of macrophage-associated cytokines in the DSF group. Corneal scarring and neovascularization were also suppressed in the DSF group. Low-vacuum scanning electron microscopy imaging showed that macrophage length was significantly shorter in the DSF group, reflecting the reduced extension of pseudopodia. These results suggest that DSF inhibited macrophage infiltration by suppressing macrophage pseudopodia formation

Importance of Vp1 Calcium-Binding Residues in Assembly, Cell Entry, and Nuclear Entry of Simian Virus 40

For polyomaviruses, calcium ions are known to be essential for virion integrity and for the assembly of capsid structures. To define the role of calcium ions in the life cycle of the virus, we analyzed simian virus 40 (SV40) mutants in which structurally deduced calcium-binding amino acids of Vp1 were mutated singly and in combination. Our study provides evidence that calcium ions mediate not only virion assembly but also the initial infection processes of cell entry and nuclear entry. Mutations at Glu48, Glu157, Glu160, Glu216, and/or Glu330 are correlated with different extents of packaging defects. The low packaging ability of mutant E216R suggests the need to position the Glu216 side chain for proper virion formation. All other mutants selected for further analysis produced virus-like particles (VLPs) but were poorly infectious. The VLPs of mutant E330K could not attach to or enter the cell, and mutant E157A-E160A and E216K VLPs entered the cell but failed to enter the nucleus, apparently as a result of premature VLP dissociation. Our results show that five of the seven acidic side chains at the two calcium-binding sites—Glu48 and Glu330 (site 1), Glu157 and Glu160 (site 2), and Glu216 (both sites)—are important for SV40 infection. We propose that calcium coordination imparts not only stability but also structural flexibility to the virion, allowing the acquisition or loss of the ion at the two sites to control virion formation in the nucleus, as well as virion structural alterations at the cell surface and in the cytoplasm early during infection