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The aim of this article is to obtain a better understanding and classification of strictly ergodic topological dynamical systems with (measurable) discrete spectrum. To that end, we first determine when an isomorphic maximal equicontinuous factor map of a minimal topological dynamical system has trivial (one point) fibers. In other words, we characterize when minimal mean equicontinuous systems are almost automorphic. Furthermore, we investigate another natural subclass of mean equicontinuous systems, so-called diam-mean equicontinuous systems, and show that a minimal system is diam-mean equicontinuous if and only if the maximal equicontinuous factor is regular (the points with trivial fibers have full Haar measure). Combined with previous results in the field, this provides a natural characterization for every step of a natural hierarchy for strictly ergodic topological models of ergodic systems with discrete spectrum. We also construct an example of a transitive almost diam-mean equicontinuous system with positive topological entropy, and we give a partial answer to a question of Furstenberg related to multiple recurrence.

Objective: Therapy for hepatocellular carcinoma (HCC) is a major challenge, and targeted therapies provide only a modest benefit in terms of overall survival. Treatment with antibodies to programmed cell death protein 1 (PD-1)/PD-L1 can restore the functions of tumor-infiltrating T cells in HCC and has shown clinical efficacy in 20% of patients with advanced HCC. Novel approaches are urgently needed to treat HCC and to augment the efficacy of immunotherapy. Methods: Tumor-bearing mice were treated with Agrocybe aegerita galectin (AAGL) alone or in combination with anti-PD-1, and the tumor sizes and lifespans of mice were determined. Transcriptome analysis, cytokine analysis, flow cytometry analysis of the number and proportion of immune cell subsets in the liver and spleen, and molecular and cellular analyses of tumors were used to define the underlying mechanisms. Results: AAGL significantly inhibited the growth of liver tumors in a dose-dependent manner. Furthermore, AAGL increased the expression of multiple cytokines and chemokines in tumor-bearing mouse livers; this effect was associated with the activation and migration of T cells and macrophages, in agreement with the in vitro results. Importantly, the aggregation of T cells and macrophages induced by AAGL in tumor-bearing mouse livers clearly enhanced the response to PD-1 blockade immunotherapy. Conclusions: The results showed that AAGL induced the activation and migration of lymphocytes to the liver, and that the combination of AAGL and anti-PD-1 may be a promising strategy for HCC treatment.

In this paper two mean forms of equicontinuity and sensitivity are mainly studied. For the equicontinuity side, it is shown that any topological dynamical system can be embedded into some almost equicontinuous in the mean system. For the sensitivity side, it turns out that the notions of sensitivity in the mean and mean sensitivity are identical in the measure-theoretical setting, though they are different in the topological setting. Moreover, levels of mean multi-variant versions of sensitivity in topological or measure-theoretical sense are completely classified.

We will review the recent development of the research related to mean equicontinuity, focusing on its characterizations, its relationship with discrete spectrum, topo-isomorphy, and bounded complexity. Particularly, the application of the complexity function in the mean metric to the Sarnak and the logarithmic Sarnak Mobius disjointness conjecture will be addressed.

Only a few work have been done for peptides from non-venom gland tissues of venomous animals. Here, with the help of the whole body transcriptomic and the hemolymph proteomic data of the Chinese scorpion Buthus martensii Karsch, we identified the first Ascaris-type peptide BmHDP from scorpion hemolymph. The precursor of BmHDP has 80 residues, including a 16 residue signal peptide and a 64 residue mature peptide. The mature peptide has 10 conserved cysteines and adopts a conserved Ascaris-type fold. Using combined inclusion body refolding and biochemical identification strategies, recombinant BmHDP was obtained successfully. Protease inhibitory assays showed that BmHDP inhibited chymotrypsin apparently at a concentration of 8 nM. Patch-clamp experiments showed that BmHDP inhibited the Kv1.3 potassium channel apparently at a concentration of 1000 nM. Coagulation experiment assays showed that BmHDP inhibited intrinsic coagulation pathway apparently at a concentration of 500 nM. To the best of our knowledge, BmHDP is the first Ascaris-type peptide from scorpion hemolymph. Our work highlighted a functional link between scorpion non-venom gland peptides and venom gland toxin peptides, and suggested that scorpion hemolymph might be a new source of bioactive peptides.

Among the patterning technologies for organic thin-film transistors (OTFTs), the fabrication of OTFT electrodes using polymer templates has attracted much attention. However, deviations in the electrode alignment occur because the coefficient of thermal expansion (CTE) of the polymer template is much higher than the CTE of the dielectric layer. Here, a novel dry-blending method is described in which SiO2 nanoparticles are filled into a grooved silicon template, followed by permeation of polydimethylsiloxane (PDMS) into the SiO2 nanoparticle gaps. The SiO2 nanoparticles in the groove are extracted by curing and peeling off PDMS to prepare a PDMS/SiO2 composite template with a nanoparticle content of 83.8 wt %. The composite template has a CTE of 96 ppm/°C, which is a reduction by 69.23% compared with the original PDMS template. Finally, we achieved the alignment of OTFT electrodes using the composite template.

Schistosoma japonicum is a parasitic worm that lives in the mesenteric vein of its host and feeds on blood, suggesting that it might be a natural resource of novel anticoagulants. Here, by comprehensive analyses of the genomic sequences of Schistosoma japonicum, a new Kunitz-type gene precursor was identified. The Kunitz-type gene precursor codes for an 18-residue signal peptide and a 60-residue mature peptide. The Kunitz peptide was functionally expressed, and it had apparent inhibitory activity towards the intrinsic coagulation pathway but no effect on the extrinsic coagulation pathway even at the high concentration of 3 μM. Enzyme and inhibitor experiments further showed that the Kunitz domain peptide was a potent and selective FXa inhibitor, so it was named Schixator (Schistosoma FXa inhibitor). Schixator inhibits coagulation factor FXa with a Ki of 2.66 nM, but had weak inhibitory activity towards chymotrypsin, FXIa, plasma kallikrein, and plasmin, and no inhibitory activity towards trypsin, elastase, FIIa or FXIIa. In vivo, the intravenous administration of Schixator into mice dramatically decreased the number of thrombi in the carotid artery in an FeCl

Let $(X,\Gamma)$ be a topological system, where $\Gamma$ is a nilpotent group generated by $T_1,\ldots, T_d$ such that for each $T\in \Gamma$, $T\neq e_\Gamma$, $(X,T)$ is weakly mixing and minimal. For $d,k\in \mathbb{N}$, let $p_{i,j}(n), 1\le i\le k, 1\le j\le d$ be polynomials with rational coefficients taking integer values on the integers and $p_{i,j}(0)=0$. We show that if the expressions $g_i(n)=T_1^{p_{i,1}(n)}\cdots T_d^{p_{i,d}(n)}$ depends nontrivially on $n$ for $i=1,2,\cdots,k$, and for all $i\neq j\in \{1,2,\ldots,k\}$ the expressions $g_i(n)g_j(n)^{-1}$ depend nontrivially on $n$, then there is a residual set $X_0$ of $X$ such that for all $x\in X_0$ \begin{equation*} \{(g_1(n)x, g_2(n)x,\ldots, g_k(n)x)\in X^k:n\in \mathbb{Z}\} \end{equation*} is dense in $X^k$., Comment: 24 pages, revised version following referees' reports, to appear in Journal d'Analyse Mathematique

In this paper we give an answer to Furstenberg’s problem on topological disjointness. Namely, we show that a transitive system $(X,T)$ is disjoint from all minimal systems if and only if $(X,T)$ is weakly mixing and there is some countable dense subset $D$ of $X$ such that for any minimal system $(Y,S)$, any point $y\in Y$ and any open neighbourhood $V$ of $y$, and for any non-empty open subset $U\subset X$, there is $x\in D\cap U$ such that $\{n\in \mathbb{Z}_{+}:T^{n}x\in U,S^{n}y\in V\}$ is syndetic. Some characterization for the general case is also given. By way of application we show that if a transitive system $(X,T)$ is disjoint from all minimal systems, then so are $(X^{n},T^{(n)})$ and $(X,T^{n})$ for any $n\in \mathbb{N}$. It turns out that a transitive system $(X,T)$ is disjoint from all minimal systems if and only if the hyperspace system $(K(X),T_{K})$ is disjoint from all minimal systems.

In this paper, the notion of measure complexity is introduced for a topological dynamical system and it is shown that Sarnak's Mobius disjointness conjecture holds for any system for which every invariant Borel probability measure has sub-polynomial measure complexity. We then apply this result to a number of situations, including certain systems whose invariant measure don't all have discrete spectrum.

Non-small cell lung cancer (NSCLC) is a malignant tumor with high morbidity and mortality. The clinical biomarkers currently used for the early diagnosis of lung cancer have poor sensitivity and specificity. Therefore, it is urgent to identify sensitive biomarkers for the early detection of NSCLC to improve the patient survival of patients. In our previously study, we identified glycoprotein alpha-1-antichymotrypsin (AACT) as an early biomarker of NSCLC. In this study, serum glycopeptides were enriched using the high-GlcNAc-specific binding lectin, AANL/AAL2, for further quantitative proteomics analysis using LC-MS/MS. A total of 55 differentially expressed proteins were identified by using demethylation labelling proteomics. Serum paraoxonase/arylesterase 1 (PON1) was selected for validation by western blotting and lectin-ELISA in samples from 120 enrolled patients. Our data showed that AANL-enriched PON1 has better diagnostic performance than total PON1 in early NSCLC, since it differed between early Stage I tumor samples and tumor-free samples (healthy and benign). Combining AANL-enriched PON1 with carcinoembryonic antigen (CEA) significantly improved the diagnostic specificity of CEA. Moreover, combined AANL-enriched PON1 and AANL-enriched AACT was significantly different between early NSCLC samples and tumor-free samples with an AUC of 0.940, 94.4% sensitivity, and 90.2% specificity. Our findings suggest that combined AANL-enriched PON1 and AANL-enriched AACT is a potential clinical biomarker for the early diagnosis of NSCLC.

Scorpion venoms are rich resources of antimicrobial peptides (AMPs). While the short-chain noncysteine-containing AMPs have attracted much attention as templates for drug development, the antimicrobial potential of long-chain noncysteine-containing AMPs has been largely overlooked. Here, by using the online HeliQuest server, we designed and analyzed a series of 14-residue fragments of Smp43, a 43-residue long-chain noncysteine-containing AMP identified from the venom of Scorpio maurus palmatus. We found that Smp43(1-14) shows high antimicrobial activity against both Gram-positive and Gram-negative bacteria and is nontoxic to mammalian cells at the antimicrobial dosage. Sequence alignments showed that the designed Smp43(1-14) displays a unique primary structure that is different from other natural short-chain noncysteine-containing AMPs from scorpions, such as Uy17, Uy192 and IsCT. Moreover, the peptide Smp43(1-14) caused concentration-dependent fluorescence increases in the bacteria for all of the tested dyes, propidium iodide, SYTOXTM Green and DiSC3-5, suggesting that the peptide may kill the bacteria through the formation of pore structures in the plasma membrane. Taken together, our work sheds light on a new avenue for the design of novel short-chain noncysteine-containing AMPs and provides a good peptide template with a unique sequence for the development of novel drugs for use against bacterial infectious diseases.

The multiple Birkhoff recurrence theorem states that for any $d\in\mathbb N$, every system $(X,T)$ has a multiply recurrent point $x$, i.e. $(x,x,\ldots, x)$ is recurrent under $\tau_d=:T\times T^2\times \ldots \times T^d$. It is natural to ask if there always is a multiply minimal point, i.e. a point $x$ such that $(x,x,\ldots,x)$ is $\tau_d$-minimal. A negative answer is presented in this paper via studying the horocycle flows. However, it is shown that for any minimal system $(X,T)$ and any non-empty open set $U$, there is $x\in U$ such that $\{n\in{\mathbb Z}: T^nx\in U, \ldots, T^{dn}x\in U\}$ is piecewise syndetic; and that for a PI minimal system, any $M$-subsystem of $(X^d, \tau_d)$ is minimal.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is becoming a troublesome issue worldwide, and anti-CRAB drug research and development is urgently needed. To identify new anti-CRAB drug leads, we investigated seven scorpion venom-derived α-helical peptides that differ in their sequence composition and length. Three peptides, Hp1404, ctriporin and Im5, showed antimicrobial activities against Acinetobacter baumannii. Further antimicrobial assays revealed that Hp1404 exhibited the best cell selectivity with high anti-CRAB and low hemolytic activities. Fluorescence assays demonstrated that Hp1404 can induce dose-dependent disruptions of the bacterial cell membrane, implying a membrane-lytic mode of action. Taken together, our work sheds light on the potential of the scorpion venom-derived peptide Hp1404 for the development of novel antimicrobial agents against CRAB infections.

Methicillin-resistant staphylococci have become growing threats to human health, and novel antimicrobials are urgently needed. Natural antimicrobial peptides (AMPs) are promising alternatives to traditional antibiotics. Here, two novel cationic α-helical antimicrobial peptides, Lausporin-1 and Lausporin-2, were identified from the venom gland of the scorpion L. australasiae through a cDNA library screening strategy. Biochemical analyses demonstrated that Lausporin-1 and Lausporin-2 are cationic α-helical amphipathic molecules. Antimicrobial assays demonstrated that the two peptides possess antibacterial activities against several species of antibiotic-resistant staphylococci. Importantly, they are active against methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus capitis, with the minimum inhibitory concentrations ranging from 2.5 to 10 μg/ml. Moreover, both peptides can induce dose-dependent plasma membrane disruptions of the bacteria. In short, our work expands the knowledge of the scorpion L. australasiae venom-derived AMPs and sheds light on the potential of Lausporin-1 and Lausporin-2 in the development of novel drugs against methicillin-resistant staphylococci.

Let $G$ be a countable group and $X$ be a totally regular curve. Suppose that $\phi:G\rightarrow {\rm Homeo}(X)$ is a minimal action. Then we show an alternative: either the action is topologically conjugate to isometries on the circle $\mathbb S^1$ (this implies that $\phi(G)$ contains an abelian subgroup of index at most 2), or has a quasi-Schottky subgroup (this implies that $G$ contains the free nonabelian group $\mathbb Z*\mathbb Z$). In order to prove the alternative, we get a new characterization of totally regular curves by means of the notion of measure; and prove an escaping lemma holding for any minimal group action on infinite compact metric spaces, which improves a trick in Margulis' proof of the alternative in the case that $X=\mathbb S^1$., Comment: 2 figures

Let $G$ be an infinite countable discrete amenable group. For any $G$-action on a compact metric space $(X,\rho)$, it turns out that if the action has positive topological entropy, then for any sequence $\{s_i\}_{i=1}^{+\infty}$ with pairwise distinct elements in $G$ there exists a Cantor subset $K$ of $X$ which is Li-Yorke chaotic along this sequence, that is, for any two distinct points $x,y\in K$, one has \[\limsup_{i\to+\infty}\rho(s_i x,s_iy)>0,\ \text{and}\ \liminf_{i\to+\infty}\rho(s_ix,s_iy)=0.\], Comment: 16 pages. This paper is dedicated to the memory of Anatoly Mikhailovich Stepin

In this paper it is proved that if a minimal system has the property that its sequence entropy is uniformly bounded for all sequences, then it has only finitely many ergodic measures and is an almost finite to one extension of its maximal equicontinuous factor. This result is obtained as an application of a general criterion which states that if a minimal system under an amenable group action is an almost finite to one extension of its maximal equicontinuous factor and has no infinite independent sets of length k for some k ≥ 2 , then it has only finitely many ergodic measures.

Among patterning technologies for organic thin-film transistors (OTFT), the fabrication of OTFT electrodes using polymer template has attracted much attention. However, deviations in electrodes alignment occur owing to a much higher coefficient of thermal expansion (CTE) of the polymer template than the CTE of the dielectric layer. Here, a novel dry blending method is described in which SiO2 nanoparticles are filled into a grooved silicon template, following by permeation of polydimethylsiloxane (PDMS) into the SiO2 nanoparticle gaps. The SiO2 nanoparticles in the groove are extracted by curing and peeling off PDMS to prepare a PDMS/SiO2 composite template with a nanoparticle content of 83.8 wt%. The composite template has a CTE of 96 ppm/°C, which a reduction of 69.23%, compared with the original PDMS template. Finally, we achieved the OTFT electrodes alignment by the composite template.

In this paper the notion of sub-exponential measure complexity for an invariant Borel probability measure of a topological dynamical system is introduced. Then a minimal distal skew product map on the torus with sub-exponential measure complexity is constructed.

We introduce higher order regionally proximal relations suitable for an arbitrary acting group. For minimal abelian group actions, these relations coincide with the ones introduced by Host, Kra and Maass. Our main result is that these relations are equivalence relations whenever the action is minimal. This was known for abelian actions by a result of Shao and Ye. We also show that these relations lift through extensions between minimal systems. Answering a question by Tao, given a minimal system, we prove that the regionally proximal equivalence relation of order d corresponds to the maximal dynamical Antolin Camarena–Szegedy nilspace factor of order at most d. In particular the regionally proximal equivalence relation of order one corresponds to the maximal abelian group factor. Finally by using a result of Gutman, Manners and Varju under some restrictions on the acting group, it follows that the regionally proximal equivalence relation of order d corresponds to the maximal pronilfactor of order at most d (a factor which is an inverse limit of nilsystems of order at most d).

O-linked N-acetylglucosamine (O-GlcNAcylation) is an important post-translational modification on serine or threonine of proteins, mainly observed in nucleus or cytoplasm. O-GlcNAcylation regulates many cell processes, including transcription, cell cycle, neural development and nascent polypeptide chains stabilization. However, the facile identification of O-GlcNAc is a major bottleneck in O-GlcNAcylation research. Herein, we report that a lectin, Agrocybe aegerita GlcNAc-specific lectin (AANL), also reported as AAL2, can be used as a powerful probe for O-GlcNAc identification. Glycan array analyses and surface plasmon resonance (SPR) assays show that AANL binds to GlcNAc with a dissociation constant (KD) of 94.6 μM, which is consistent with the result tested through isothiocyanate (ITC) assay reported before (Jiang S, Chen Y, Wang M, Yin Y, Pan Y, Gu B, Yu G, Li Y, Wong BH, Liang Y, et al. 2012. A novel lectin from Agrocybe aegerita shows high binding selectivity for terminal N-acetylglucosamine. Biochem J. 443:369–378.). Confocal imaging shows that AANL co-localizes extensively with NUP62, a heavily O-GlcNAcylated and abundant nuclear pore glycoprotein. Furthermore, O-GlcNAc-modified peptides could be effectively enriched in the late flow-through peak from simple samples by using affinity columns Sepharose 4B-(AANL) or POROS-(AANL). Therefore, using AANL affinity column, we identified 28 high-confidence O-linked HexNAc-modified peptides mapped on 17 proteins involving diverse cellular progresses, including transcription, hydrolysis progress, urea cycle, alcohol metabolism and cell cycle. And most importantly, major proteins and sites were not annotated in the dbOGAP database. These results suggest that the AANL lectin is a new useful tool for enrichment and identification of O-GlcNAcylated proteins and peptides.

Agrocybe aegerita galectin (AAL) has been reported to possess anti-tumor activity in tumor cells. The anti-metastasis activity of AAL in breast cancer and its possible mechanisms involved were investigated in this study. A bio-distribution assay showed AAL was highly absorbed by the lung. Administration of AAL (0.75 mg/kg twice or 1.5 mg/kg once) significantly inhibited pulmonary metastases of 4T1 cells and prolonged survival time of tumor-bearing mice. The binding between AAL and 4T1 cells relied on the carbohydrates recognition of AAL. AAL showed anti-proliferation activity against 4T1 cells with an IC50 of 4.11 M for 24 h treatment and 0.75 M for 48 h treatment. AAL induced apoptosis of 4T1 cells in a Caspase-3/7-dependent manner. Moreover, AAL inhibited migration and invasion of 4T1 cells, and decreased MMP 9 activity was found to be involved. This study would help to enhance the use of A. aegerita in nutritional and medicinal application.

The changes of the wettability of the solid surfaces have attracted massive attention due to their important practical implications in numerous fields. As a new subject, the research on the wettability under the different environments is still in its early stage. So the fundamental research must be performed for the practical applications under different environments. However, it is seldom that the comprehensive wettability of a surface in air, in water and in oil has been reported. In this paper, the authors investigated the wettability of the stainless steel mesh coated with polyurethane in the above three different environments. The surface of the uncoated mesh was found to be hydrophobic in air, but the surface of the coated mesh was superhydrophilic in air. More interestingly, the surfaces of the coated meshes were superoleophilic in water and superhydrophobic in oil. Due to the coated meshes with these wettabilities were fabricated via a facile two-step method, the presented method may be adopted for large-scale industrial production, in various fields, such as icing prevention or the oil-field industry.

In this paper we study $C^*$-algebra version of Sarnak Conjecture for noncommutative toral automorphisms. Let $A_\Theta$ be a noncommutative torus and $\alpha_\Theta$ be the noncommutative toral automorphism arising from a matrix $S\in GL(d,\mathbb{Z})$. We show that if the Voiculescu-Brown entropy of $\alpha_{\Theta}$ is zero, then the sequence $\{\rho(\alpha_{\Theta}^nu)\}_{n\in \mathbb{Z}}$ is a sum of a nilsequence and a zero-density-sequence, where $u\in A_\Theta$ and $\rho$ is any state on $A_\Theta$. Then by a result of Green and Tao, this sequence is linearly disjoint from the M\"obius function., Comment: 29 pages

The family of pairwise independently determined (PID) systems, i.e., those for which the independent joining is the only self joining with independent 2-marginals, is a class of systems for which the long standing open question by Rokhlin, of whether mixing implies mixing of all orders, has a positive answer. We show that in the class of weakly mixing PID one finds a positive answer for another long-standing open problem, whether the multiple ergodic averages $$\frac{1}{N}\sum\limits_{n = 0}^{N - 1} {{f_1}} \left( {{T^n}x} \right)...{f_d}\left( {{T^{dn}}x} \right),N \to \infty $$ almost surely converge.

This study presents the measurement error analysis of two dimensional resistive sensor arrays sharing row and column connections to reduce the interconnections complexity, based on the setting non-current scanned electrodes zero potential (S-NCSE-ZP) method. The authors provide a mathematical model to evaluate the performance of the circuit and optimise its design by calculating the voltage of the electrodes in sensor array. To reveal the effects of the circuit parameters on the performance of the circuit, the authors perform a parametric study on the array size, adjacent elements, and on-resistance of switches. The theoretical results show that the on-resistance of switches significantly influences on the performance of the S-NCSE-ZP circuit. Moreover, array size and adjacent elements also play an important role in the performance of the circuit. Finally, the authors present an efficient circuit based on the zero potential method, to overcome on the measurement inaccuracy.

The Jewett–Krieger theorem states that each ergodic system has a strictly ergodic topological model. In this article, we show that for an ergodic system one may require more properties on its strictly ergodic model. For example, the orbit closure of points in diagonal under face transforms may be also strictly ergodic. As an application, we show the pointwise convergence of ergodic averages along cubes, which was firstly proved by Assani (J Anal Math 110:241–269, 2010).

In this paper it is shown that every non-periodic ergodic system has two topologically weakly mixing, fully supported models: one is non-minimal but has a dense set of minimal points; and the other one is proximal. Also for independent interests, for a given Kakutani-Rokhlin tower with relatively prime column heights, it is demonstrated how to get a new taller Kakutani-Rokhlin tower with same property, which can be used in Weiss's proof of the Jewett-Krieger's theorem and the proofs of our theorems. Applications of the results are given.