We studied hyperonic interactions by lattice QCD simulations through a coupled channel formalism. Our approach to baryon–baryon interactions derives a potential from inverting the Schrödinger ...equation using a Nambu–Bethe–Salpeter (NBS) wave function simulated on the lattice. The quark mass dependences and flavor SU(3) breaking effects of the potential matrix are also discussed by comparing with results of gauge configurations obtained with different quark masses. Our numerical results are obtained from three ensembles of 2+1-flavor QCD gauge configurations, which correspond to mπ∼700,570 and 410 MeV, provided by the PACS-CS Collaboration.
An 87-year-old,Japanese woman was shown to have a submucosal tumor-like lesion with a deep,central ulceration covered with thick,whitish exudate in the stomach.Biopsy showed Candida tropicalis but ...not Helicobacter pylori(H.pylori).She had no predisposing factors or history of peptic ulcers nor had taken non-steroidal anti-inflammatory drugs(NSAIDs),diagnosed with Candida-associated gastric ulcer.Though cured of the lesion,she developed another ulcer in a different position,in which Candida was demonstrated but H.pylori was undetectable.This is the first case of recurrent Candida-associated gastric ulcer in the world.Detected in both the original and recurrent lesions in an H.pylori-negative patient with no antecedent ulcers who had not taken NSAIDs,Candida is considered,contrary to the prevailing opinion,to play an etiologic role in ulcer formation.
The nucleon(N)-Omega(Ω) system in the S-wave and spin-2 channel (S25) is studied from the (2+1)-flavor lattice QCD with nearly physical quark masses (mπ≃146MeV and mK≃525MeV). The time-dependent HAL ...QCD method is employed to convert the lattice QCD data of the two-baryon correlation function to the baryon-baryon potential and eventually to the scattering observables. The NΩ(S25) potential, obtained under the assumption that its couplings to the D-wave octet-baryon pairs are small, is found to be attractive in all distances and to produce a quasi-bound state near unitarity: In this channel, the scattering length, the effective range and the binding energy from QCD alone read a0=5.30(0.44)(−0.01+0.16)fm, reff=1.26(0.01)(−0.01+0.02)fm, B=1.54(0.30)(−0.10+0.04)MeV, respectively. Including the extra Coulomb attraction, the binding energy of pΩ−(S25) becomes BpΩ−=2.46(0.34)(−0.11+0.04)MeV. Such a spin-2 pΩ− state could be searched through two-particle correlations in p-p, p-nucleus and nucleus-nucleus collisions.
Baryon–baryon potentials are obtained from 3-flavor QCD simulations with the lattice volume L≃4 fm, the lattice spacing a≃0.12 fm, and the pseudo-scalar-meson mass Mps=469–1171 MeV. The NN scattering ...phase-shifts and the mass of H-dibaryon in the flavor SU(3) limit are extracted from the resultant potentials by solving the Schrödinger equation. The NN phase-shifts in the SU(3) limit is shown to have qualitatively similar behavior as the experimental data. A bound H-dibaryon in the SU(3) limit is found to exist in the flavor-singlet JP=0+ channel with the binding energy of about 26 MeV for the lightest quark mass Mps=469 MeV. Effect of flavor SU(3) symmetry breaking on the H-dibaryon is estimated by solving the coupled-channel Schrödinger equation for ΛΛ–NΞ–ΣΣ with the physical baryon masses and the potential matrix obtained in the SU(3) limit: a resonant H-dibaryon is found between ΛΛ and NΞ thresholds in this treatment.
Imaginary-time Nambu–Bethe–Salpeter (NBS) wave function is introduced to extend our previous approach for hadron–hadron interactions on the lattice. Scattering states of hadrons with different ...energies encoded in the NBS wave function are utilized to extract non-local hadron–hadron potential. “The ground state saturation”, which is commonly used in lattice QCD but is hard to be achieved for multi-baryons, is not required. We demonstrate that the present method works efficiently for the nucleon–nucleon interaction (the potential and the phase shift) in the S01 channel.
This study aims to provide a simple way to identify the possibility of tetrabromobisphenol A (TBBPA) present in polymers without the need for complicated separation with expensive equipment. Since ...the presence of phenolic hydroxyl groups is known to be identifiable by the reduction of Fe3+ to Fe2+ in a ferric coloring reagent, the possibility of TBBPA being present in a polymer can be screened by a photometric measurement. A mixed solution of iron(III) nitrate and potassium hexacyanide(III) acid was used as a ferric coloring reagent. With this method, the concentration of TBBPA can be estimated from the photometric absorbance corresponding to the depth of the blue color produced by reduction of the ferric reagent in the presence of Fe(NO3)3. The limit of detection (LOD) was determined to be approximately 2 mg/kg using the Student’s t-test (99% confidence), and a reproducibility of approximately 3% was determined by the relative standard deviation (RSD) from measurements of calibration samples (n = 7). Furthermore, TBBPA in actual polymer samples was screened without the need for any complex processing steps. Because this colorimetric method measures TBBPA by detecting phenolic groups, it may overestimate the TBBPA concentration in the presence of other similar phenolic substances. Nonetheless, this simple colorimetric method should help to quickly identify the presence of TBBPA in various polymers.
We propose a new compartment model of COVID-19 spread, the broken-link model, which includes the effect from unconnected infectious links of the transmission. The traditional SIR-type epidemic models ...are widely used to analyze the spread status, and the models show the exponential growth of the number of infected people. However, even in the early stage of the spread, it is proven by the actual data that the exponential growth did not occur all over the world. We presume this is caused by the suppression of secondary and higher-order transmissions of COVID-19. We find that the proposed broken-link model quantitatively describes the mechanism of this suppression, which leads to the shape of epicurves of confirmed cases are governed by the probability of unconnected infectious links, and the magnitudes of the cases are proportional to expR0 in each infectious surge generated by a virus of the basic reproduction number R0, and is consistent with the actual data.
There is increasing evidence that cyclic and linear carbonates, commonly used solvents in Li ion battery electrolytes, are unstable in the presence of superoxide and thus are not suitable for use in ...rechargeable Li–air batteries employing aprotic electrolytes. A detailed understanding of related decomposition mechanisms provides an important basis for the selection and design of stable electrolyte materials. In this article, we use density functional theory calculations with a Poisson–Boltzmann continuum solvent model to investigate the reactivity of several classes of aprotic solvents in nucleophilic substitution reactions with superoxide. We find that nucleophilic attack by O2 •– at the O-alkyl carbon is a common mechanism of decomposition of organic carbonates, sulfonates, aliphatic carboxylic esters, lactones, phosphinates, phosphonates, phosphates, and sulfones. In contrast, nucleophilic reactions of O2 •– with phenol esters of carboxylic acids and O-alkyl fluorinated aliphatic lactones proceed via attack at the carbonyl carbon. Chemical functionalities stable against nucleophilic substitution by superoxide include N-alkyl substituted amides, lactams, nitriles, and ethers. The results establish that solvent reactivity is strongly related to the basicity of the organic anion displaced in the reaction with superoxide. Theoretical calculations are complemented by cyclic voltammetry to study the electrochemical reversibility of the O2/O2 •– couple containing tetrabutylammonium salt and GCMS measurements to monitor solvent stability in the presence of KO2 • and a Li salt. These experimental methods provide efficient means for qualitatively screening solvent stability in Li–air batteries. A clear correlation between the computational and experimental results is established. The combination of theoretical and experimental techniques provides a powerful means for identifying and designing stable solvents for rechargeable Li–air batteries.
The ΔΔ dibaryon resonance d⁎(2380) with (JP,I)=(3+,0) is studied theoretically on the basis of the 3-flavor lattice QCD simulation with heavy pion masses (mπ=679,841 and 1018 MeV). By using the HAL ...QCD method, the central Δ-Δ potential in the S37 channel is obtained from the lattice data with the lattice spacing a≃0.121 fm and the lattice size L≃3.87 fm. The resultant potential shows a strong short-range attraction, so that a quasi-bound state corresponding to d⁎(2380) is formed with the binding energy 25-40 MeV below the ΔΔ threshold for the heavy pion masses. The tensor part of the transition potential from ΔΔ to NN is also extracted to investigate the coupling strength between the S-wave ΔΔ system with JP=3+ and the D-wave NN system. Although the transition potential is strong at short distances, the decay width of d⁎(2380) to NN in the D-wave is kinematically suppressed, which justifies our single-channel analysis at the range of the pion mass explored in this study.
Bioactive mediators derived from omega-3 eicosapentaenoic acid (EPA) elicit potent anti-inflammatory actions. Here, we identified novel EPA metabolites, including 8,18-dihydroxyeicosapentaenoic acid ...(8,18-diHEPE), 11,18-diHEPE, 12,18-diHEPE, and 17,18-diHEPE from 18-HEPE. Unlike resolvins E1 and E2, both of which are biosynthesized by neutrophils via the 5-lipoxygenase pathway, these metabolites are biosynthesized by eosinophils via the 12/15-lipoxygenase pathway. Among them, two stereoisomers of 17,18-diHEPE, collectively termed resolvin E3 (RvE3), displayed a potent anti-inflammatory action by limiting neutrophil infiltration in zymosan-induced peritonitis. The planar structure of RvE3 was unambiguously determined to be 17,18-dihydroxy-5Z,8Z,11Z,13E,15E-EPE by high resolution NMR, and the two stereoisomers were assigned to have 17,18R- and 17,18S-dihydroxy groups, respectively, using chemically synthesized 18R- and 18S-HEPE as precursors. Both 18R- and 18S-RvE3 inhibited neutrophil chemotaxis in vitro at low nanomolar concentrations. These findings suggest that RvE3 contributes to the beneficial actions of EPA in controlling inflammation and related diseases.
Endogenous mediators that control aberrant inflammation are of interest as potential targets of new therapeutics.
Here, we identified a novel omega-3 fatty acid-derived anti-inflammatory mediator 17,18-diHEPE, denoted as resolvin E3.
Resolvin E3 has a potent inhibitory action on neutrophil chemotaxis both in vitro and in vivo.
The significance of this study is the identification of a novel endogenous lipid mediator with a potent anti-inflammatory property.