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We report a computational survey of chemical doping of silver(II) fluoride, which has recently attracted attention as an analogue of La2CuO4-a known precursor of high-temperature superconductors. By introducing fluorine defects (vacancies or interstitial adatoms) into the crystal structure, we obtain nonstoichiometric, electron- and hole-doped polymorphs of AgF2±x. We find that the ground-state solutions show a strong tendency for localization of defects and of the associated electronic states, and the resulting doped phases exhibit insulating or semiconducting properties. Furthermore, the distribution of Ag(I)/Ag(III) sites which appear in the crystal structure points to the propensity of the AgF2 system for phase separation upon chemical doping, which is in line with observations from previous experimental attempts. Overall, our results indicate that chemical modification may not be a feasible way to achieve doping in bulk silver(II) fluoride, which is considered essential for the emergence of high-Tc superconductivity.First-principles calculations have been carried out for the 20-electron transition metal complexes (Cp)2TMO and their molecular wires (Cp = C5H5, C5(CH3)H4, C5(CH3)5; TM = Cr, Mo, W). The calculation results at the BP86/def2-TZVPP level reveal that the ground state is singlet and the optimized geometries are in good agreement with the experimental values. The analysis of frontier molecular orbitals shows that two electrons in the highest occupied molecular orbital HOMO-1 are mainly localized on cyclopentadienyl and oxygen ligands. Furthermore, the nature of the TM-O bond was investigated with the energy decomposition analysis-natural orbitals for chemical valence (EDA-NOCV). The attraction term in the intrinsic interaction energies ΔEint is mainly composed of two important parts, including electrostatic interaction (about 52% of the total attractive interactions ΔEelstat + ΔEorb) and orbital interaction, which might be the major determinant of the stability of these (Cp)2TMO complexes. All of the TM-O bonds should be described as electron-sharing σ single bonds [(Cp)2TM]+-[O]- with the contribution of 53-57% of ΔEorb and two π backdonations from the occupied p orbitals of oxygen ligands into vacant π* MOs of the [(Cp)2TM]+ fragments, which are 35-40% of ΔEorb. The results of bond order and interaction energy from EDA-NOCV calculations suggest the influence of the radius of TM and methyl in the interactions between TM and O in (Cp)2TMO. M344 Additionally, the relativistic effects slightly amplify the strength of bonding with increasing ΔEorb for the EDA-NOCV calculations on three metal complexes (C5H5)2TMO. Finally, the geometries, electronic structures, and magnetics of infinitely extended systems, [(C5H5)TMO]∞, have also been explored. The results of the density of states (DOS) and band structure revealed that [(C5H5)CrO]∞ and [(C5H5)WO]∞ are semiconductors with the narrow bands, whereas [(C5H5)MoO]∞ behaves as metal.Paratrimerins J-Y (1-13 and 16-18), new dimeric coumarins, were obtained from the EtOH(aq) extract of the stems of Paramignya trimera (Rutaceae) utilizing LC/MS guided isolation. The structures of the dimeric coumarins were elucidated based on 1D/2D NMR spectroscopic and HR-ESIMS data analyses. The absolute configurations of paratrimerins J-Y along with those of two known dimers paratrimerins A (14) and B (15) were established on the basis of the experimental and simulated ECD data. In addition, the absolute configurations of the sugar units of paratrimerins A, B, and J-V (1-15) were confirmed by LC/MS analysis on l-cysteine methyl ester and phenyl isothiocyanate derivatives. The variety of the absolute configurations of the dimeric diastereomers 1-15 highlighted a diversity in stereochemical outcomes following a Diels-Alder biosynthesis in P. trimera. With regard to P. trimera being a recently emerging medicinal resource for liver cancer, the dimers 1-18 were evaluated for cytotoxicity against a wide panel of human cancer cell lines. Paratrimerin W (16) was cytotoxic toward Huh7 hepatocellular carcinoma, HT1080 fibrosarcoma, and HT29 colorectal cancer cells with IC50 values of 14.9, 18.4, and 22.5 μM, respectively.We present a dynamic perturbation-response model of proteins based on the Gaussian Network Model, where a residue is perturbed periodically, and the dynamic response of other residues is determined. The model shows that periodic perturbation causes a synchronous response in phase with the perturbation and an asynchronous response that is out of phase. The asynchronous component results from the viscous effects of the solvent and other dispersive factors in the system. The model is based on the solution of the Langevin equation in the presence of solvent, noise, and perturbation. We introduce several novel ideas The concept of storage and loss compliance of the protein and their dependence on structure and frequency; the amount of work lost and the residues that contribute significantly to the lost work; new dynamic correlations that result from perturbation; causality, that is, the response of j when i is perturbed is not equal to the response of i when j is perturbed. As examples, we study two systems, nameleatures of allosteric manipulation.Although bacteria with 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity have been used to mitigate biotic and abiotic stresses in crops, it is not well known whether the ACC deaminase gene (acdS) in Pseudomonas azotoformans is related to the alleviation of salt stress by the bacterium. This study aimed to evaluate the effects of acdS in P. azotoformans strain CHB 1107 on the nutrient uptake and growth of tomato plants under salt stress. The acdS mutant (CHB 1107 M) of P. azotoformans CHB 1107 was obtained through bacterial conjugation. Wild-type (CHB 1107 WT) and CHB 1107 M were used to inoculate tomato plants grown in a soil or solution with an electrical conductivity of 6 dS/m adjusted by NaCl. CHB 1107 M completely lost the ability to produce ACC deaminase, whereas the complementation of acdS in CHB 1107 M preserved its ACC deaminase activity. CHB 1107 WT significantly reduced the production of ethylene and proline by tomato plants under salt stress, increasing the shoot and root dry weights of tomato plants compared with the noninoculated control and CHB 1107 M.