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Mean dimension may decrease after taking the natural extension. In this paper we show that mean dimension is preserved by natural extension for an endomorphism on a compact metrizable abelian group. As an application, we obtain that the mean dimension of an algebraic cellular automaton coincides with the mean dimension of its natural extension, which strengthens a result of Burguet and Shi [Israel J. Math. (to appear).] with a different proof. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) serves as a pivotal plant hormone involved in regulating plant defense mechanisms against biotic stresses, but the extent of its biological significance in relation to peanut resistance is currently lacking. This study elucidated the involvement of salicylic acid (SA) in conferring broad-spectrum disease resistance in peanuts through the experimental approach of inoculating SA-treated leaves. In several other plants, the salicylate hydroxylase genes are the typical susceptible genes (S genes). Here, we characterized two SA hydroxylase genes (AhS5H1 and AhS5H2) as the first S genes in peanut. Recombinant AhS5H proteins catalyzed SA in vitro, and showed SA 5-ydroxylase (S5H) activity. Overexpression of AhS5H1 or AhS5H2 decreased SA content and increased 2,5-DHBA levels in Arabidopsis, suggesting that both enzymes had a similar role in planta. Moreover, overexpression of each AhS5H gene increased susceptibility to Pst DC3000. Analysis of the transcript levels of defense-related genes indicated that the expression of AhS5H genes, AhNPR1 and AhPR10 was simultaneously induced by chitin. Overexpression of each AhS5H in Arabidopsis abolished the induction of AtPR1 or AtPR2 upon chitin treatment. Eventually, AhS5H2 expression levels were highly correlated with SA content in different tissues of peanut. Hence, the expression of AhS5H1 and AhS5H2 was tissue-specific. [ABSTRACT FROM AUTHOR]

We study fibrations in the category of cubespaces/nilspaces. We show that a fibration of finite degree f : X → Y between compact ergodic gluing cubespaces (in particular nilspaces) factors as a (possibly countable) tower of compact abelian Lie group principal fiber bundles over Y. If the structure groups of f are connected then the fibers are (uniformly) isomorphic (in a strong sense) to an inverse limit of nilmanifolds. In addition we give conditions under which the fibers of f are isomorphic as subcubespaces. We introduce regionally proximal equivalence relations relative to factor maps between minimal topological dynamical systems for an arbitrary acting group. We prove that any factor map between minimal distal systems is a fibration and conclude that if such a map is of finite degree then it factors as a (possibly countable) tower of principal abelian Lie compact group extensions, thus achieving a refinement of both the Furstenberg's and the Bronstein–Ellis structure theorems in this setting. [ABSTRACT FROM AUTHOR]

3D printing technologies are a promising approach to treat intra‐oral bone defects, especially those with poor regenerative potential. However, there is a lack of evidence regarding the impact of internal design specifications on the bone regenerative potential. Here, an in silico approach to optimize the internal design of calcium phosphate‐based scaffolds for bone regeneration is proposed. Based on an in silico model of neotissue formation, a gyroid 3D‐printed scaffold is designed and manufactured using UV stereolithography of bioceramic materials. An orthogonal lattice structure 3D‐printed scaffold and a particulate xenograft are used as control groups. The scaffolds are implanted subperiosteally under a shell on rat calvarium for 4 or 8 weeks and bone neoformation performances are investigated by nanofocus computed tomography and decalcified histology. After 8 weeks, the gyroid group is associated with a higher ingrowth potential of the bone and is characterized by signs of osteoinduction (newly formed bone islands). The bone to material contact is similar between the gyroid and the particulate groups. The present results reinforce this in silico modeling strategy to design calcium phosphate‐based 3D scaffolds and the gyroid experimental internal architecture seems to be highly promising for intra‐oral bone regeneration applications. [ABSTRACT FROM AUTHOR]

We show that if G is a finitely generated group of subexponential growth and X is a nondegenerate Suslinian continuum, then any continuous action of G on X is not expansive. [ABSTRACT FROM AUTHOR]

In this study, the rolling process of the warm-rolled duplex-phase Mg–8.3Li–3.1Al–1.09Si alloy and the strengthening mechanism of as-rolled Mg–Li alloy were investigated. The highest ultimate tensile strength (UTS, 323.66 ± 19.89 MPa) could be obtained using a three-pass rolling process with a 30% thickness reduction for each pass at 553 K. The strength of the as-rolled LAS831 alloy is determined by a combination of second-phase strengthening, grain refinement strengthening, dislocation strengthening, and load-transfer reinforcement. Of these factors, dislocation strengthening, which is caused by strain hardening of the α-Mg phase, can produce a good strengthening effect but also cause a decrease in plasticity. The Mg2Si phase is broken up into particles or strips during the rolling process. After three passes, the AlLi particles were transformed into an AlLi phase, and the Mg2Si particles and nanosized AlLi particles strengthened the second phase to form a hard phase. The average size of the DRXed β-Li grains decreased with each successive rolling pass, and the average size of recrystallized grains in the three-pass-rolled LAS831 alloy became as low as 0.27 μm. The interface between the strip-like Mg2Si phase and the α-Mg phase is characterized by semicoherent bonding, which can promote the transfer of tensile and shear forces from the matrix to the strip-like Mg2Si phase, thereby improving the strength of the matrix and thus strengthening the LAS831 alloy. [ABSTRACT FROM AUTHOR]

Given a length function L on the R -modules of a unital ring R , for each sofic group Γ we define a mean length for every locally L-finite R Γ-module relative to a bigger R Γ-module. We establish an addition formula for the mean length. We give two applications. The first one shows that for any unital left Noetherian ring R , R Γ is stably direct finite. The second one shows that for any Z Γ -module M , the mean topological dimension of the induced Γ-action on the Pontryagin dual of M coincides with the von Neumann–Lück rank of M. [ABSTRACT FROM AUTHOR]

We introduce an invariant, called mean rank, for any module ℳ {\mathcal{M}} of the integral group ring of a discrete amenable group Γ, as an analogue of the rank of an abelian group. It is shown that the mean dimension of the induced Γ-action on the Pontryagin dual of ℳ {\mathcal{M}} , the mean rank of ℳ {\mathcal{M}} , and the von Neumann–Lück rank of ℳ {\mathcal{M}} all coincide. As applications, we establish an addition formula for mean dimension of algebraic actions, prove the analogue of the Pontryagin–Schnirelmann theorem for algebraic actions, and show that for elementary amenable groups with an upper bound on the orders of finite subgroups, algebraic actions with zero mean dimension are inverse limits of finite entropy actions. [ABSTRACT FROM AUTHOR]

We estimated the additive genetic variation and heritability of vibrio resistance in the clam Meretrix petechialis by using four statistical models to analyze data from challenge tests. A total of 2541 individuals from 23 full-sib families were infected with V. parahaemolyticus , which causes vibriosis in clams. The daily mortality was recorded, and the experiment was terminated after 18 days, when the death rate fell to approximately zero. The overall mortality of clams approached 60% at the end of the test, and significantly different survival rates were observed among families, e.g., six full-sib families suffered 80–97% mortality, whereas 9 families showed only 17–48% mortality. Variance components were analyzed using cross-sectional models, and moderate to high heritability was estimated for vibrio resistance in both the linear model (0.31–0.32) and the sire-dam threshold model (0.53) but not in the animal threshold model (0.006). Estimated breeding values (EBVs) of the two types of models showed high and positive correlations (0.92–0.99), which meant that these models showed similar utility for predicting breeding value. These results indicate that an efficacious and reliable challenge method of infecting M. petechialis clams with V. parahaemolyticus was achieved and that vibrio resistance in clam might be genetically improved through selective breeding. Statement of relevance The clam Meretrix petechialis is an important commercial cultured mollusc species in China. Our results provided a reliable challenge method of infecting clam with V. parahaemolyticus and estimated basic genetic evaluation for vibrio resistance, which should be useful for the design and operation of a practical vibrio resistance selective breeding program in the clam M. petechialis . [ABSTRACT FROM AUTHOR]

Rice plants contain high basal levels of salicylic acid (SA), but some of their functions remain elusive. To elucidate the importance of SA homeostasis in rice immunity, we characterized four rice SA hydroxylase genes (OsSAHs) and verified their roles in SA metabolism and disease resistance. Recombinant OsSAH proteins catalyzed SA in vitro, while OsSAH3 protein showed only SA 5-hydroxylase (SA5H) activity, which was remarkably higher than that of other OsSAHs that presented both SA3H and SA5H activities. Amino acid substitutions revealed that three amino acids in the binding pocket affected SAH enzyme activity and/or specificity. Knockout OsSAH2 and OsSAH3 (sahKO) genes conferred enhanced resistance to both hemibiotrophic and necrotrophic pathogens, whereas overexpression of each OsSAH gene increased susceptibility to the pathogens. sahKO mutants showed increased SA and jasmonate levels compared to those of the wild type and OsSAH-overexpressing plants. Analysis of the OsSAH3 promoter indicated that its induction was mainly restricted around Magnaporthe oryzae infection sites. Taken together, our findings indicate that SA plays a vital role in immune signaling. Moreover, fine-tuning SA homeostasis through suppression of SA metabolism is an effective approach in studying broad-spectrum disease resistance in rice. [ABSTRACT FROM AUTHOR]

Abstract: We introduce the topological pressure for any sub-additive potentials of a countable discrete amenable group action and any given open cover, and establish a local variational principle for it. [Copyright &y& Elsevier]

The rapid emergence of bacterial coinfection caused by cytosolic bacteria has become a huge threat to public health worldwide. Past efforts have been devoted to discover the broad-spectrum antibiotics, while the emergence of antibiotic resistance encourages the development of antibacterial agents. In essence, bacterial virulence is a factor in antibiotic tolerance. However, the discovery and development of new antibacterial drugs and special antitoxin drugs is much more difficult in the antibiotic resistance era. Herein, we hypothesize that antitoxin hemolytic activity can serve as a screening principle to select antibacterial drugs to combat coinfection from natural products. Being the most abundant natural drug of plant origins, flavonoids were selected to assess the ability of antibacterial coinfections in this paper. Firstly, we note that four flavonoids, namely, baicalin, catechin, kaempferol, and quercetin, have previously exhibited antibacterial abilities. Then, we found that baicalin, kaempferol, and quercetin have better inhibitions of hemolytic activity of Hla than catechin. In addition, kaempferol and quercetin, have therapeutic effectivity for the coinfections of Staphylococcus aureus and Pseudomonas aeruginosa in vitro and in vivo. Finally, our results indicated that kaempferol and quercetin therapied the bacterial coinfection by inhibiting S. aureus α-hemolysin (Hla) and reduced the host inflammatory response. These results suggest that antitoxins may play a promising role as a potential target for screening flavonoids to combat bacterial coinfection. [ABSTRACT FROM AUTHOR]

l -norleucine, an isomer of leucine, stimulates the anabolic process of insulin. However, it is not known if and how it improves insulin sensitivity and insulin resistance. This experiment describes the generation of an insulin resistance model using high glucose-induced cells and the administration of 1.0 mmol/L l -norleucine for 48 h, to observe the effects on metabolism and gene expression in skeletal muscle cells. The results showed that l -norleucine significantly increased mitochondrial ATP content, decreased the amount of reactive oxygen species (ROS) and promoted the expression of mitochondrial generation-related genes TFAM, AMPK, PGC-1α in cells under high glucose treatment; at the same time, l -norleucine also increased glucose uptake, suggesting that l -norleucine increased insulin sensitivity and improved insulin resistance. This study suggesting that l -norleucine improves insulin resistance by ameliorating oxidative stress damage of mitochondria, improving mitochondrial function, and improving insulin sensitivity in skeletal muscle cell caused by high glucose, rather than by altering mitochondrial efficiency. • l -norleucine increased mitochondrial ATP content, decreased the amount of ROS, improved mitochondrial function. • l -norleucine increased glucose uptake, increased insulin sensitivity. • l -norleucine promoted the expression of mitochondrial generation-related genes TFAM, AMPK, PGC-1α, improved insulin resistance. [ABSTRACT FROM AUTHOR]

Corrosion fatigue (CF) tests of 316LN weld metal were investigated in high-temperature water at different strain rates (0.0004–0.4%/s) under strain amplitude of 0.6%. Relationship between CF life and strain rate was proposed and environmental fatigue correction factor F en was also calculated. It was found that the γ/δ phase boundary was more susceptible to cracking at low strain rates and δ-ferrite worked as a barrier to retard the crack growth at high strain rates. Mechanisms of CF damage involving the effects of strain rate, hydrogen, δ-ferrite and residual strain on crack growth are also discussed. • Quantitative relation between fatigue life of 316LN weld metal and strain rate is purposed. • Effect of δ-ferrite changed with strain rate due to the interaction between localized deformation and environmental damage. • Mechanisms of CF damage involving the effects of hydrogen and residual strain on crack growth are proposed. [ABSTRACT FROM AUTHOR]