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31.
Prunus mahaleb L. fruit has long been used in the production of traditional liqueurs. The fruit also displayed scavenging and reducing activity, in vitro. The present study focused on unravelling peripheral and central protective effects, antimicrobial but also anti-COVID-19 properties exerted by the water extract of P. mahaleb. Anti-inflammatory effects were studied in isolated mouse colons exposed to lipopolysaccharide. Neuroprotection, measured as a blunting effect on hydrogen-peroxide-induced dopamine turnover, was investigated in hypothalamic HypoE22 cells. Antimicrobial effects were tested against different Gram+ and Gram- bacterial strains. Whereas anti-COVID-19 activity was studied in lung adenocarcinoma H1299 cells, where the gene expression of ACE2 and TMPRSS2 was measured after extract treatment. The bacteriostatic effects induced on Gram+ and Gram- strains, together with the inhibition of COX-2, TNFα, HIF1α, and VEGFA in the colon, suggest the potential of P. mahaleb water extract in contrasting the clinical symptoms related to ulcerative colitis. The inhibition of the hydrogen peroxide-induced DOPAC/DA ratio indicates promising neuroprotective effects. Finally, the downregulation of the gene expression of ACE2 and TMPRSS2 in H1299 cells, suggests the potential to inhibit SARS-CoV-2 virus entry in the human host. Overall, the results support the valorization of the local cultivation of P. mahaleb.  相似文献   
32.
非线性涡黏性系数模型和代数应力模型联系了线性涡黏性系数湍流模型和完整的微分 雷诺应力模型.随着它们受到日益关注,其形式也越来越多样化.本篇综述的目的是对这些模 型加以总结并比较它们之间的共同点及不同之处,指出它们与完整微分雷诺应力模型之间的 关系,以及相对于线性涡黏性系数模型而言它们在预报流场上所具有的优势.  相似文献   
33.
In single-crystal nickel-based superalloys, the lattice mismatch associated with interface coherency between γ matrix and γ' precipitates has a strong influence on mechanical properties. The unconstrained lattice misfit in a single-crystal of the MC2 nickel-based superalloy is determined using convergent beam electron diffraction measurements and finite element calculations. The apparent lattice parameters of both constrained phases are obtained in thin foils, using a new multi-pattern approach, which allows for unambiguous determination of all the lattice parameters considering the real symmetry of the strained crystals. Finite element calculations are used to establish relations between the constrained and unconstrained lattice parameters, with the stress relaxation resulting from the thin foil geometry taken into account.  相似文献   
34.
This review addresses recent advances in the field of glassy carbon electrodes film‐modified by acidic functionalities. Attention was posed at the architecture of the functionalizing surface film and at practical applications of the relevant sensors. To facilitate the reading, some summarizing tables were included, each one regarding a certain type of surface modification. A final section is aimed at detailing some remarks emerging from the analysis of the reviewed matter. This allowed highlighting the potentialities of the examined sensors, and evidencing some criticisms about how some of their performances were presented in the relevant papers.  相似文献   
35.
We construct perturbative quantum gravity in a generally covariant way. In particular our construction is background independent. It is based on the locally covariant approach to quantum field theory and the renormalized Batalin–Vilkovisky formalism. We do not touch the problem of nonrenormalizability and interpret the theory as an effective theory at large length scales.  相似文献   
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Fusion cross-sections for the 7Li + 12C reaction have been measured at energies above the Coulomb barrier by the direct detection of evaporation residues. The heavy evaporation residues with energies below 3 MeV could not be separated out from the α-particles in the spectrum and hence their contribution was estimated using statistical model calculations. The present work indicates that suppression of fusion cross-sections due to the breakup of 7Li may not be significant for 7Li + 12C reaction at energies around the barrier.  相似文献   
38.
In this work we obtain a model to describe the relaxativity of water molecules, adsorbed on macromolecules, as a function of the concentration. Excellent agreement with experimental data was obtained. The model allows us to estimate the adsorption energy of water molecules on different sites of the macromolecules.  相似文献   
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A threshold-photoelectron-coincidence spectrum of HBr has been recorded in the 32.2-35.8 eV photon energy range, with a resolution of approximately 0.01 eV, using a synchrotron radiation source. The X (3)Sigma(-) and a (1)Delta(2) states of the HBr(2+) dication are clearly observed in the spectrum, while there is no clear evidence for the formation of the b (1)Sigma(+) electronic state. For the first two states, the vibrational states v=0-3 have been resolved, while for the ground X (3)Sigma(-) state also spin-orbit splitting has been detected. The results appear in good agreement with previous experimental observations. A comparison with theoretical predictions indicates the role of "noncovalent" contributions to the interaction between the two atomic partners for the formation of metastable states.  相似文献   
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