Filtenborglund7665
The total viable count of the control sample exceeded 7 logarithms of the number of colony forming units per gram (log CFU/g) after 11 days of cold storage (7.01 ± 0.14 log CFU/g) versus 15 days for the ε-PL-g-PLA film (7.37 ± 0.06 log CFU/g) and the nisin-g-PLA film (6.83 ± 0.10 log CFU/g). The results showed that covalent immobilized antibacterial packaging films had positive impacts on the shelf life and quality of fresh beef. Therefore, a covalent immobilized antibacterial packaging system could be a novel preservative method for foods.Celastrol, a friedelane-type triterpenoid isolated from the genus Triperygium, possesses antitumor, anti-inflammatory, and immunosuppressive activities. A total of 42 celastrol derivatives (1a-1t, 2a-2l, and 3a-3j) were synthesized and evaluated for their immunosuppressive activities. Compounds 2a-2e showed immunosuppressive effects, with IC50 values ranging from 25 to 83 nM, and weak cytotoxicity (CC50 > 1 μM). Compound 2a, with a selectivity index value 31 times higher than that of celastrol, was selected as a lead compound. Further research showed that 2a exerted its immunosuppressive effects by inducing apoptosis and inhibiting cytokine secretion via Lck- and ZAP-70-mediated signaling pathways.Black sorghum [Sorghum bicolor (L.) Moench] is characterized by the black appearance of the pericarp and production of 3-deoxyanthocyanidins (3-DOA), which are valued for their cytotoxicity to cancer cells and as natural food colorants and antioxidant additives. The black pericarp phenotype is not fully penetrant in all environments, which implicates the light spectrum and/or photoperiod as the critical factor for trait expression. In this study, black- or red-pericarp genotypes were grown under regimes of visible light, visible light supplemented with UVA or supplemented with UVA plus UVB (or dark control). Pericarp 3-DOAs and pericarp pigmentation were maximized in the black genotype exposed to a light regime supplemented with UVB. Changes in gene expression during black pericarp development revealed that ultraviolet light activates genes related to plant defense, reactive oxygen species, and secondary metabolism, suggesting that 3-DOA accumulation is associated with activation of flavonoid biosynthesis and several overlapping defense and stress signaling pathways.Simulating chemical systems on quantum computers has been limited to a few electrons in a minimal basis. We demonstrate experimentally that the virtual quantum subspace expansion (Takeshita, T.; Phys. Rev. X 2020, 10, 011004, 10.1103/PhysRevX.10.011004) can achieve full basis accuracy for hydrogen and lithium dimers, comparable to simulations requiring 20 or more qubits. We developed an approach to minimize the impact of experimental noise on the stability of the generalized eigenvalue problem, a crucial component of the quantum algorithm. In addition, we were able to obtain an accurate potential energy curve for the nitrogen dimer in a quantum simulation on a classical computer.Indium selenide (InSe) has a high electron mobility and tunable direct band gap, enabling its potential applications to electronic and optoelectronic devices. Here, we report the fabrication of InSe photodetectors with high on/off ratios and ultrahigh photoresponsivity, using ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer films as the top-gate dielectric. Benefiting from the successful suppression of the dark current down to ∼10-14A in the InSe channel by tuning the three different polarization states in ferroelectric P(VDF-TrFE) and improved interface properties using h-BN as a substrate, the ferroelectric-gated InSe photodetectors show a high on/off ratio of over 108, a high photoresponsivity up to 14 250 AW-1, a high detectivity up to 1.63 × 1013 Jones, and a fast response time of 600 μs even at zero-gate voltage. read more The present results highlight the role of ferroelectric P(VDF-TrFE) in tuning the carrier transport of InSe and may provide an avenue for the development of InSe-based photodetectors.Major light-harvesting complex (LHCII) trimers in plants induce the thermal dissipation of absorbed excitation energy against photooxidative damage under excess light conditions. LHCII trimers in green algae have been thought to be incapable of energy dissipation without additional quencher proteins, although LHCIIs in plants and green algae are homologous. In this study, we investigated the energy-dissipative capabilities of four distinct types of LHCII trimers isolated from the model green alga Chlamydomonas reinhardtii using spectroscopic analysis. Our results revealed that the LHCII trimers possessing LHCII type II (LHCBM5) and LHCII type IV (LHCBM1) had efficient energy-dissipative capabilities, whereas LHCII type I (LHCBM3/4/6/8/9) and type III (LHCBM2/7) did not. On the basis of the amino acid sequences of LHCBM5 and LHCBM1 compared with the other LHCBMs, we propose that positively charged extra N-terminal amino acid residues mediate the interactions between LHCII trimers to form energy-dissipative states.Deacetoxycephalosporin C synthase (DAOCS) is a nonheme iron(II) and 2-oxoglutarate (α-KG)-dependent oxygenase that catalyzes the oxidative ring expansion of penicillin N (penN) to deacetoxycephalosporin C (DAOC). Earlier reported crystal structures of DAOCS indicated that the substrate penicillin binds at the same site of succinate, leading to the proposal of the unusual "ping-pong" mechanism. However, more recent data provided evidence of the formation of ternary DAOCS·α-KG·penN complex, and thus DAOCS should follow the usual consensus mechanism of α-KG-dependent nonheme iron(II) oxygenases. Nevertheless, how DAOCS catalyzes the ring expansion is unknown. In this paper, on the basis of the crystal structure, we constructed two reactant models and performed a series of combined quantum mechanics/molecular mechanics (QM/MM) calculations to illuminate the catalysis of DAOCS. The binding mode of substrate was found to be crucial in determining which hydrogen atom in two methyl groups is first abstracted and whether the second H-abstraction to be abstracted in the final desaturation step locates in a suitable orientation. The highly reactive FeIV-oxo species prefers to abstract a hydrogen atom from one of two methyl groups in penN to trigger the ring arrangement. After the H-abstraction, the generated methylene radical intermediate can easily initiate the ring arrangement. First, the C-S bond cleaves to generate a thiyl radical, which is in concert with the formation of the terminal C═C double bond; the newly generated thiyl radical then rapidly shifts to the more stable tertiary C atom to complete ring expansion. In the final step, the FeIII-OH species abstracts the second hydrogen to give the desaturated DAOC product. During the catalysis, no active site residue is directly involved in the chemistry, which implies that the other pocket residues except the coordinate ones with iron play a role only in anchoring the substrate.