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This paper is devoted to establishing a critical value of the concentration of one intermediary reactant which determines whether pattern solutions of a class of Brusselator models exist or not. We introduce a new method to compute the degree index of the related linear operator so that the obtained sufficient conditions are easier to verify than those in the known references. The proofs mainly rely on Leray-Schauder degree theory, implicit function theorem and analytical techniques.

Diabetes has become a global and serious health issues which causes a variety of complications. This study aims to explore the hypoglycemic effect of Crassostrea gigas polysaccharide (CGPS) and the dynamic changes in the endogenous small molecule metabolites of urine from normal group, model group and CGPS high dose group by metabolomic approach (UPLC-Q-TOF-MS). In our study, the CGPS treatment could reduce the fasting blood glucose levels and recover the triglycerides (TG), total cholesterol (TC) and glycosylated serum protein (GSP) levels in serum of diabetic mice. Urine samples in normal group, model group and CGPS high dose group were dispersed in the PLS-DA score plots. Nineteen metabolites in urine such as l-carnitine, hippuric acid, pantothenate and ornithine were selected as potential therapeutic biomarkers and related metabolic pathways of CGPS for treating diabetes. They were mainly involved in amino acid metabolism, carbohydrate metabolism and purine metabolism. These data suggested that CGPS has antidiabetic activity and urine metabolites provided new understanding of CGPS for treating diabetes and its complications.

In this work, the pristine and Ag-composited TiO2-Bronze (TiO2-B) nanowires are successfully synthesized by hydrothermal method using anatase(P25) as titanium source. The SEM, TEM results reveal that the silver particles are well distributed on the TiO2-B nanowires. Also, the TiO2-B/Ag nanowires are dispersed very well, which demonstrate more Li-ion insertion/extraction hosts exposed to the electrolyte. Moreover, the electrochemical performance tests suggest that compared with the pristine TiO2-B, the Ag-composited TiO2-B (TiO2-B/Ag) shows remarkably higher capacities (~286mAhg-1, closing to the theoretical capacity) and superior rate capability. The reasons causing this performance difference are ascribed to the added silver particles, which could reduce the Li-ion diffusion length and improve the material electrical conductivity.

Two new methods of simulating Levy processes are presented in this paper. The first one is to simulate the small jump part of a Levy process by the classical rejection method, which can generate the exact sampling. The second is to simulate the Levy process by the compound Poisson process with corrected density at zero, it is efficient, robust, and can be used in multivariate setting.

Acute myelod leukemia (AML), as a uncontrolled proliferation of cells, was arrested differentiation of progenitor cells. The present study aimed to explore Tanshinone IIA (TIIA) effects on OCI-AML3 and the involvement of the MAPK signaling pathway and miR-497 in TIIA-mediated effects. Cell growth percentage was detected using a cell counting kit. Expression of miR-497 was detected by qPCR. Phosphorylated ERK1/2, JNK and p38 were assessed using western blot. The growth percentage of OCI-AML3 decreased and the effected time increased with increasing TIIA concentration. The miR-497 was upregulated and the p-ERK1/2 was decreased when the TIIA added. TIIA cannot influence the p-ERK1/2. Hence, the proliferation of OCI-AML3 cells was raising. However, when the p-ERK1/2 was inhibited, there no influence on the miR-497 expression after TIIA added. TIIA upregulates miR-497, and decrease the p-ERK1/2 expression, when TIIA simulated OCI-AML3 cell in vitro. And in miR-497 might be involved in the regulation of proliferation in this process.

Carbon dots codoped with nitrogen and sulfur (N,S-CDs) were synthesized by a single-step hydrothermal method. The N, S-CDs were characterized by transmission electron microscopy, X-ray diffraction, FTIR and X-ray photoelectron spectroscopy in terms of surface morphology, functional groups and surface composition and elemental composition. The CDs possess intense fluorescence and excitation wavelength dependent emission wavelengths. Fluorescence is strongest at an excitation wavelength of 360 nm and typically peaks at 440 nm. The fluorescence of the N,S-CDs is quenched by Cr(VI) ion. Under the 360 nm excitation wavelength condition, fluorescence intensity decreases linearly on increasing the Cr(VI) concentration from 1 μM to 10 μM, and the LOD at a signal-to-noise ratio of 3 was about 0.2 μM. The method was applied to the quantitation of Cr(VI) in spiked real samples and gave satisfactory results.

A Ca(2+)-dependent GalNAc/Man-specific lectin (CSL) from Cyclina sinensis was isolated, and its stimulatory action was characterized in yeast. CSL showed a potent effect on the production of ethanol by Saccharomyces cerevisiae. In this work, the changes in the protein expression profiles of S. cerevisiae after 24h of incubation with CSL were analyzed using label-free quantitative proteomics. A total of 1410 proteins were identified, but only 117 proteins showed significant differences in normalized volume (p

Sulfated polysaccharides from Crassostrea gigas (SCGP) were successfully prepared using chlorosulfonic acid-pyridine method. The structure of SCGP was determined by high performance liquid chromatography (HPLC), Fourier transform infrared spectrometry (FT-IR) and nuclear magnetic resonance (NMR). The results of spectra indicated the substitution by the sulfate group primarily appeared at C-6. Further, the antioxidant activities of CGP and SCGP were contrasted, and SCGP exhibited the higher DPPH, hydroxyl and ABTS radical scavenging activities. The study was further evaluated the hepatoprotective effect of SCGP in alcoholic liver injury mice and determined total cholesterol (T-CHO), low density lipoprotein cholesterol (LDL-C), total bilirubin (TBIL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels of serum in mice. The results demonstrated that SCGP improved blood biochemical levels and had a hepatoprotective effect. Additionally, metabolite analysis of serum was performed by UHPLC-Q-TOF-MS to assess the hepatoprotection effect of SCGP in alcoholic liver injury mice. A total of twenty-one metabolites were identified as potential biomarkers. The result suggested that SCGP altered the metabolic pathways including amino acid metabolism, oxidative stress and immune response. These data provided reference of the SCGP of treating alcoholic liver injury.

In this paper, a new algorithm about the self-similar exponent of self-similar processes is introduced which is used to explore long memory in financial time series. This method can work for more general broad-sense self-similar processes. We prove that this algorithm performs much better than the classical methods.

A lectin secreted from Andrias davidianus skin (ADL) was purified by affinity chromatography on porcine stomach mucin (type III) (PSM)-crosslinked albumin, followed by gel filtration on Sephadex G-100 and HPLC on TSK gel G3000PWXL. The purified lectin was found to be a dimeric protein, as revealed by SDS-PAGE and MALDI-TOF analysis. SDS-PAGE showed that the ADL protein had a molecular mass of 17 kDa. ADL produced an 8.5 kDa band when examined using SDS-PAGE under reducing conditions. ADL agglutinated native and trypsinized human B erythrocytes. The hemagglutination activity was inhibited by glycoproteins, such as PSM and asialo-PSM, but not by any of the monosaccharides tested. The activity was stable between 4 °C and 50 °C. Significant ADL activity was observed between pH 4–5. The lectin reaction did not depend on the presence of the divalent cation Ca2+ or Mg2+. The N-terminal ADL sequence was determined to be VGYTVGATPM. The lectin exhibited antibacterial activity, involving growth and respiration inhibition in Escherichia coli, Enterobacter aerogenes, Staphylococcus aureus, Bacillus subtilis and Shewanella sp. Furthermore, ADL showed inhibition activity against the yeast Saccharomyces cerevisiae. These findings suggest that ADL plays an important role in the innate immunity of A. davidianus on the body surface.

Crassostrea gigas polysaccharides (CGP) were obtained by different drying methods: freeze-drying (FD), spray-drying (SD) or rotary evaporation-drying (RED). The physicochemical properties of CGP were evaluated on the basis of polysaccharide content, protein content, color characteristics, FT-IR spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Antioxidant activities were researched three different free radicals, including DPPH free radicals, ABTS free radicals and reducing power. The results demonstrated that FDCGP, SDCGP and REDCGP have different physicochemical properties and antioxidant activities. Contrasted with FDCGP and REDCGP, SDCGP exhibited stronger antioxidant abilities. Therefore, considering the polysaccharides appearances and antioxidant activities, the spray drying method is a decent selection for the preparation of such polysaccharides, and it should be selected for application in the food industry.

In this paper we study the non-existence of non-constant steady state (i.e., stationary pattern) for a Chemotaxis model with the volume-filling effect and logistic cell growth. We establish the critical value of the chemotactic coefficient between the existence and the non-existence of stationary pattern. The proofs mainly rely on the Maximum Principle, the Implicit Function Theorem and the Finite Covering Theorem. This work is a supplement and perfection of the known reference.

This paper deals with the existence of periodic solutions of a nonhomogeneous string with Dirichlet-Neumann condition. The authors consider the case that the period is irrational multiple of space length and prove that for some irrational number, zero is not the accumulation point of the spectrum of the associated linear operator. This result can be used to prove the existence of the periodic solution avoid using Nash-Moser iteration.

Let {W1(t), t ∈ R+} and {W2(t), t ∈ R+} be two independent Brownian motions with W1(0) = W2(0) = 0. {H(t) = W1(|W2(t)|), t ∈ R+} is called a generalized iterated Brownian motion. In this paper, the Hausdorff dimension and packing dimension of the level sets $$\{ t \in [0,T],H(t) = x\} $$ are established for any 0 < T ≤ 1.

A lectin, Cyclina sinensis (Gmelin) (CSL), was isolated from hemolymph C. sinensis by ion-exchange on Cellulose DE52 and purified by gel filtration on Sephadex G-100 and HPLC on TSK gel G4000PW XL . SDS-PAGE showed that the CSL protein had a molecular mass of 72 kDa, had consisted of 40 and 18 kDa subunits. The lectin activity of CSL was Ca 2+ -denpendent. The total carbohydrate content of CSL was found to be 16.2%. According to the principle of β-elimination reaction, the oligosaccharide moiety and peptide moiety of CSL might belong to O -glucosidic linkage. CSL was found to agglutinate rabbit erythrocytes and yeast Saccharomyces cerevisiae . The hemagglutination activity was inhibited by GalNAc and Man. CSL was observed to promote the yeast cells growth and ethanol production by yeast cells. The number of yeast and ethanol production increased with increasing concentration of CSL. In addition, the nitric oxide (NO) production increased as CSL concentration increased. The results indicate that CSL can be a potential yeast stimulator in fermentation process.

We prove the existence of the local time of the Ornstein–Uhlenbeck type process X = { X t , t ∈ R + } driven by a general Levy process. The conditions of the continuity in time variable t and the regularity property of the local time are given, under mild regularity conditions on the driving Levy process. These results give information about the local properties of sample functions of the process.

Let X = { X t , t ≥ 0 } be a Levy process, and γ 0 = sup { α ≥ 0 : lim inf a → 0 a − α E T ( a , 1 ) ∞ } , where T ( a , 1 ) = ∫ 0 1 I { | X t | ≤ a } d t . Taylor (1986) showed that the packing dimension of the trajectory of X is γ 0 . An open question from Pruitt and Taylor (1996) is: Is it true that γ 0 = inf { α ≥ 0 : a − α T ( a , 1 ) → ∞ a.s. as a → 0 } ? In this paper, we give some answers to this question.

In this paper, the Hausdorff dimension of the range for a Markov process of Ornstein–Uhlenbeck type { X ( t ) , t ∈ R + } on R is given. We also investigate the Hausdorff dimension of the process in R d case.

In order to understand the oxidation resistance of a 2D C/SiC composite protected with self-healing filler in the inter-bundle pores, SiB 4 particles as the filler were infiltrated into the inter-bundle pores of 2D C/SiC composite by slurry infiltration process. The SiB 4 particles were combined with SiC during the chemical vapor deposition (CVD) SiC coating process. Isothermal oxidation tests of the as-received modified composite were carried out in air at temperatures ranging from 500 to 1000 °C. SEM and EDS results showed that all the open inter-bundle pores of the C/SiC composite can be filled with SiB 4 particles. The SiB 4 filler can hinder the inwards diffusion of oxygen in air, and protect the carbon fibres and carbon interphase from oxidation. As a result, the modified composite lost weight slowly, and showed no obvious decrease in flexural strength at the temperatures of 500–900 °C for an oxidation time of 10 h.

In this paper we prove a global existence result for nonlinear Klein–Gordon equations with small data in infinite homogeneous waveguids, R2×M, where M=(M,g) is a Zoll manifold. The method is based on the normal forms, the eigenfunction expansion for M and the special distribution of eigenvalues of Laplace–Beltrami on Zoll manifold.

A lectin (HFL) was isolated from the brown alga, Hizikia fusiformis, through ion exchange on cellulose DE52 and HPLC with a TSK-gel G4000PWXL column. SDS-PAGE showed that HFL had a molecular mass of 16.1 kDa. The HPLC (with a TSK-gel G4000PWXL column) indicated that HFL is a tetramer in its native state. The total carbohydrate content was 41%. Glucose, galactose and fucose were the monosaccharide units of HFL, and the normalized mol% values were 6, 14 and 80, respectively. HFL contains a large amount of the acidic amino acid, Asx. The β-elimination reaction suggested that the oligosaccharide and peptide moieties of HFL may belong to the N-glucosidic linkage. The amino acid sequences, of about five segments of HFL, were acquired by MALDI-TOF/TOF, and the sequences have no homology with other lectins. HFL was found to agglutinate sheep erythrocytes. The hemagglutination activity was inhibited by thyroglobulin, from bovine thyroid, but not by any of the monosaccharides tested. The lectin reaction was independent of the presence of the divalent cation Ca(2+). HFL showed free radical scavenging activity against hydroxyl, DPPH and ABTS(+) radicals.

A water-soluble polysaccharide was isolated from Crassostrea gigas (CGPS-1) by hot-water extraction, isoelectric precipitation, hydrolysis and ultrafiltration without using ethanol. Based on the calibration with Dextran, CGPS-1 had a molecular weight of approximately 6.5 × 106 Da. CGPS-1 was analyzed using high-performance liquid chromatography, Fourier-transform infrared spectroscopy and 1H and 13C nuclear magnetic resonance spectroscopy. Based on the data, CGPS-1 was found to be a uniform glucose polymer. The protective effect of CGPS-1 on acute carbon tetrachloride- and chronic ethanol-induced liver injury was investigated in mice. Treatment with CGPS-1 decreased serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), and malondialdehyde (MDA) levels; increased superoxide dismutase (SOD) activity; and improved hepatic injury in both the acute and chronic models of liver injury in mice. These results suggest that CGPS-1 possesses potent hepatoprotective activity.

In this study, the properties of a GalNAc/Gal-specific lectin from the sea mussel Crenomytilus grayanus (CGL) and its effects on Saccharomyces cerevisiae were studied. The heat stability of CGL was determined and the free energy change (G') of hemagglutination activity of the lectin in denaturation process was evaluated by Van’t Hoff plot. The amino acid sequences about six segments of CGL were acquired by mass spectrum (MS) and the sequences have no homology with other lectins. In the effect of CGL, it can be observed that CGL can promote the yeast cells growth and ethanol production by yeast cells. In addition, the nitric oxide (NO) production decreases with increasing CGL concentration, except for the concentration of 3.25 mg/l. The results show that CGL is the potential yeast stimulators in fermentation process. Key words : Lectin, sea mussel, Saccharomyces cerevisiae, ethanol, nitric oxide.

By using Aspergillus sp. acid protease, the preparation of skin secretion hydrolysates from giant salamander (Andrias davidianus) was studied. Through orthogonal test, the optimum hydrolytic condition as follows: temperature 55°C, pH2.0, E/S value is 0.03%, and hydrolysis time 3h. MALDI-TOF mass spectrometry showed that molecular weights of hydrolysates were below 3.5kDa.