Cryoprotective effects and mechanisms of soybean oligosaccharides on the grass carp (Ctenopharyngodon idellus) surimi during frozen storage.

BACKGROUND: Conventional cryoprotectant mixtures (sucrose and sorbitol) impart excessive sweetness and calories to surimi. Therefore, there is a need to explore alternative cryoprotectants with low sweetness and low-calorie content. The cryoprotective effects and possible mechanisms of soybean oligosaccharides (SBOS) on the frozen stability of grass carp (Ctenopharyngodon idellus) surimi were investigated during 120 days of frozen storage in a comparison with commercial cryoprotectants (4% sucrose and 4% sorbitol, w/w). RESULTS: SBOS at 6-8% (w/w) and commercial cryoprotectants could restrain water mobility and reduce thawing loss of frozen surimi by increasing non-freezable water content. SBOS could maintain the structural stability of proteins by preventing sulfhydryl groups from being rapidly oxidized to disulfide bonds, retarding the reduction of the solubility, Ca2+-ATPase activity and α-helix content of myofibrillar proteins (MP), as well as hindering the increasing surface hydrophobicity of MP of surimi during 120 days of frozen storage. The introduction of SBOS increased the gel strength and water-holding capacity of frozen-stored surimi. Compared with commercial cryoprotectants, 8% SBOS was more effective in stabilizing protein structure, whereas it was slightly less effective with respect to ice-forming inhibition. CONCLUSION: The results obtained in the present study suggest that 8% SBOS could be potentially developed as a new cryoprotectant for surimi as a result of its ice-forming inhibition abilities and protein structure stability. © 2024 Society of Chemical Industry.

Charge-transfer state dynamics in all-polymer solar cells: formation, dissociation and decoherence.

All-polymer solar cells have made substantial achievements in recent years, offering numerous unsettled subjects for mechanical researchers. In order to quantitatively study the influence of the molecular electrostatic potential on the charge generation proposed by the experimenter, we simulate the ultrafast dynamics of the charge-transfer (CT) state at the interface between two polymer chains, which are respectively regarded as the donor and acceptor in all-polymer solar cells. The formation of a stable CT state is found to be sensitive to the distance between two oppositely charged polarons and the relevant critical electrostatic potential is thus quantified, which is in good agreement with experiments. In order to get insight into the dependence of the dissociation of the CT state on the width of the interfacial layer, two quantities are calculated: one is the Coulomb capture radius between the two polarons and the other is the quantum trace distance which serves as the fingerprint of the quantum coherence between them. The dissociation of the CT state is found to take place within an ultrafast timescale for an optimum interfacial width. The classical spatial distance and the quantum trace distance manifest a converging trend, suggesting a decoherence scenario for the charge separation in all-polymer solar cells.

Disorder-free dynamic localization in non-adiabatic processes: entanglement entropy and OTOC.

We investigate the localization in a one-dimensional modified Peierls model with a non-adiabatic dynamic method. Different from the polaron scenario, here the localization stems from extensive conserved local quantities in the disorder-free lattice. Both the entanglement entropy and out-of-time-ordered correlator (OTOC) show the oscillating feature of dynamically generated localization. Although the strong interaction between electrons may suppress the dynamical features of the localization, but the effect of many-body localization is not observed. The role of disorder presented at finite temperature is discussed as well. The electrons diffuse in a classical manner. Benefitting from the indication of OTOC, it is found that the Anderson localization becomes dominant instead of dynamic localization as observed in disorder-free lattices.

Non-intubated anesthesia in patients undergoing video-assisted thoracoscopic surgery: A systematic review and meta-analysis.

INTRODUCTION: Non-intubated anesthesia (NIA) has been proposed for video-assisted thoracoscopic surgery (VATS), although how the benefit-to-risk of NIA compares to that of intubated general anesthesia (IGA) for certain types of patients remains unclear. Therefore, the aim of the present meta-analysis was to understand whether NIA or IGA may be more beneficial for patients undergoing VATS. METHODS: A systematic search of Cochrane Library, Pubmed and Embase databases from 1968 to April 2019 was performed using predefined criteria. Studies comparing the effects of NIA or IGA for adult VATS patients were considered. The primary outcome measure was hospital stay. Pooled data were meta-analyzed using a random-effects model to determine the standard mean difference (SMD) with 95% confidence intervals (CI). RESULTS AND DISCUSSION: Twenty-eight studies with 2929 patients were included. The median age of participants was 56.8 years (range 21.9-76.4) and 1802 (61.5%) were male. Compared to IGA, NIA was associated with shorter hospital stay (SMD -0.57 days, 95%CI -0.78 to -0.36), lower estimated cost for hospitalization (SMD -2.83 US, 95% CI -4.33 to -1.34), shorter chest tube duration (SMD -0.32 days, 95% CI -0.47 to -0.17), and shorter postoperative fasting time (SMD, -2.76 days; 95% CI -2.98 to -2.54). NIA patients showed higher levels of total lymphocytes and natural killer cells and higher T helper/T suppressor cell ratio, but lower levels of interleukin (IL)-6, IL-8 and C-reactive protein (CRP). Moreover, NIA patients showed lower levels of fibrinogen, cortisol, procalcitonin and epinephrine. CONCLUSIONS: NIA enhances the recovery from VATS through attenuation of stress and inflammatory responses and stimulation of cellular immune function.