Blautia producta displays potential probiotic properties against dextran sulfate sodium-induced colitis in mice

Blautia has attracted attention because of its potential efficacy in ameliorating host energy metabolism and inflammation.This study aims to investigate the influences of Blautia producta D4 on colitis induced by dextran sulfate sodium(DSS)and to reveal the underlying mechanisms.Results showed that B.producta D4 intervention significantly relieved body weight loss,and suppressed the elevation of pro-inflammatory cytokines(including interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),and interleukin-1β(IL-1β))and excessive oxidative stress(myeloperoxidease(MPO)activity,superoxide dismutase(SOD)activity,glutathione peroxidase(GSH-Px)activity,and malondialdehyde(MDA)level)in colitis mice.Moreover,the concentrations of tight junction proteins(occludin,claudin-1,and ZO-1)related to the intestinal barrier were obviously elevated,and colitis-related TLR4/NF-κB pathway activation was remarkably inhibited after B.producta D4 intervention.The intestinal microbial disorder was evidently ameliorated by increasing the relative abundance of Clostridium sensu stricto 1,Bifidobacterium,GCA-900066225,Enterorhabdus,and reducing the relative abundance of Lachnospiraceae NK4A136 group.In conclusion,oral administration of B.producta D4 could ameliorate DSS-induced colitis by suppressing inflammatory responses,maintaining the intestinal barrier,inhibiting TLR4/NF-κB pathway,and regulating intestinal microbiota balance.These results are conducive to accelerate the development of B.producta D4 as a functional probiotic for colitis.

A bionic controllable strain membrane for cell stretching at air–liquid interface inspired by papercutting

Lung diseases associated with alveoli,such as acute respiratory distress syndrome,have posed a long-term threat to human health.However,an in vitro model capable of simulating different deformations of the alveoli and a suitable material for mimicking basement membrane are currently lacking.Here,we present an innovative biomimetic controllable strain membrane(BCSM)at an air–liquid interface(ALI)to reconstruct alveolar respiration.The BCSM consists of a high-precision three-dimensional printing melt-electrowritten polycaprolactone(PCL)mesh,coated with a hydrogel substrate—to simulate the important functions(such as stiffness,porosity,wettability,and ALI)of alveolar microenvironments,and seeded pulmonary epithelial cells and vascular endothelial cells on either side,respectively.Inspired by papercutting,the BCSM was fabricated in the plane while it operated in three dimensions.A series of the topological structure of the BCSM was designed to control various local-area strain,mimicking alveolar varied deformation.Lopinavir/ritonavir could reduce Lamin A expression under over-stretch condition,which might be effective in preventing ventilator-induced lung injury.The biomimetic lung-unit model with BCSM has broader application prospects in alveoli-related research in the future,such as in drug toxicology and metabolism.

Characterization of Failure Mechanisms of Duplex and Graded Thermal Barrier Coatings Exposed to Thermal Shock Test

The beginning of failure of a (ZrO2-7%Y2O3)/(Ni-22%Co-17%Cr-12.5%Al-0.6%Y) duplex andgraded coating systems on lnconel 617 and IN738LC in burner rig tests has been characterized.The test conditions are 40 s heating up to 75O℃ substrate temperature followed by 80 s aircooling. Failure is considered at the appearance of the first bright spot during heating period.Stresses due to thermal expansion mismatch strains on cooling are the probable cause of life-limiting in this conditions of testing.

Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics

The planarization mechanism of alkaline copper slurry is studied in the chemical mechanical polishing （CMP） process from the perspective of chemical mechanical kinetics.Different from the international dominant acidic copper slurry,the copper slurry used in this research adopted the way of alkaline technology based on complexation. According to the passivation property of copper in alkaline conditions,the protection of copper film at the concave position on a copper pattern wafer surface can be achieved without the corrosion inhibitors such as benzotriazole（BTA）,by which the problems caused by BTA can be avoided.Through the experiments and theories research,the chemical mechanical kinetics theory of copper removal in alkaline CMP conditions was proposed. Based on the chemical mechanical kinetics theory,the planarization mechanism of alkaline copper slurry was established. In alkaline CMP conditions,the complexation reaction between chelating agent and copper ions needs to break through the reaction barrier.The kinetic energy at the concave position should be lower than the complexation reaction barrier,which is the key to achieve planarization.

The effect of metal ions with different valences on the retardation of soil–bentonite barrier materials and its mechanism

In this paper, with K＋, Ca2＋ and Fe3＋ as the objects of study, retardation of soil-bentonite （SB） barrier materials for metal ions with different valences is investigated, and the adsorption mechanism, migration patterns and permeation behavior are explored so as to provide a theoretical basis for their application. The results show that the adsorption process for metal ions with different valences by SB barrier materials is fast, and the higher the valence, the greater the adsorption capacity. The fitting of the adsorption process conforms to pseudo-second-order adsorption kinetics and Langmuir-Freundlich adsorption equation, which explains that chemical adsorption is the dominating state and that the SB surface has certain heterogeneity. The permeability coefficient of K＋, Ca2＋ and Fe3＋ in SB each has a maximum and the higher the valence, the sooner the maximum appears. Also the higher the valence, the more obvious the effect on SB retardation performance; and the sooner the ion breaks through the barrier wall completely, that is, the wall＇s retardation performance for higher valent ions may decline.

Functional films based on mechanoactivated starch with prolonged release of preservative

Use of active edible films containing an antimicrobial agent-a new method of extending the shelf life of food products.Ensuring the controlled release of the preservative from the film is an urgent task.This work aims to introduce a new environmentally friendly process for the production of antifungal starch films with a prolonged release of a preservative using mechanoactivation in a rotor-stator device (RSD).Active films based on mechanoactivated starch hydrogels containing 0–5.0% (w/w) benzoic acid as a preservative and chitosan as a solubilizing additive (St-BA-Ch),as well as films containing sodium benzoate (St-SB) for comparison,were obtained by the casting method.Films were characterized using optical and atomic force microscopy,X-ray diffraction and tensile and moisture permeability testing data.It was found that benzoic acid is present in the St-BА-Ch-films in the form of submicron particles.St-BА-Ch films showed greater tensile strength and a lower release rate of the preservative into model media compared to St-SB films.It is established that mechanical activation of casting hydrogels in RSD allows increasing the strength films by an average of 2 times,as well as reducing the release rate of the preservative and the vapor permeability of the films.The antifungal activity of the films was confirmed using Aspergillus niger.The developed active St-BА-Ch film can be recommended for use in the food industry to extend the shelf life of food products.