Search

Oxidized gellan gum (OGG) hydrogel beads as delivery systems for resveratrol were fabricated by ionic cross-linking with calcium chloride (CaCl

Pullulanase (EC 3.2.1.41) is a starch-debranching enzyme in the α-amylase family and specifically cleaves α-1,6-glycosidic linkages in starch-type polysaccharides, such as pullulan, β-limited dextrin, glycogen, and amylopectin. It plays a key role in debranching and hydrolyzing starch completely, thus bring improved product quality, increased productivity, and reduced production cost in producing resistant starch, sugar syrup, and beer. Plenty of researches have been made with respects to the discovery of either thermophilic or mesophilic pullulanases, however, few examples meet the demand of industrial application. This review presents the progress made in the recent years from the first aspect of characteristics of pullulanases. The heterologous expression of pullulanases in different microbial hosts and the methods used to improve the expression effectiveness and the regulation of enzyme production are also described. Then, the function evolution of pullulanases from a protein engineering view is discussed. In addition, the immobilization strategy using novel materials is introduced to improve the recyclability of pullulanases. At the same time, we indicate the trends in the future research to facilitate the industrial application of pullulanases.

A series of novel 4″

A series of lanthanide porphyrins, [ LnIII(TPPSIV) ]n·n H 5 O 2 ( Ln = La , Sm , Eu ; H2TPPS = tetra(4-sulfonatophenyl)porphyrin), have been synthesized through solvothermal reactions and structurally characterized by single-crystal X-ray diffraction. These compounds are characterized by a condensed three-dimensional (3-D) porous open framework. Magnetic measurements reveal that these compounds show ferromagnetic, antiferromagnetic and paramagnetic behavior, respectively. All of the compounds exhibit highly thermal stability. The FT-IR and adsorption measurement of CO 2 were also studied.

A new type of ionic ferroelectric based on a chiral salen-type Schiff base erbium(III) complex (ErL) was synthesized by the reaction of erbium nitrate with the ligand N,N′-bis(3,5-dichlorosalicylidene)-(1S,2S)-1,2-cyclohexylenediamine (L). The structures of the ligand L and the complex ErL were determined by single-crystal X-ray diffraction. The results indicated that ErIII not only acts as central metal atom to coordinate with two Schiff base ligands, but also as Lewis acid catalyst to promote the partial decomposition of another salen-type Schiff base ligand. The central ErIII atom adopts an octacoordinate square antiprismatic arrangement with Λ absolute configuration, coordinating with all nitrogen and oxygen atoms of two ligands due to the influence of the strong electron-withdrawing group on the Schiff base ligand. The complex ErL exhibits good SHG and ferroelectric properties. The results provide a simple and effective approach to construct rare earth complexes coordinated with nitrogen and oxygen atoms of salen-type Schiff base ligands with technologically important properties such as SHG activity and ferroelectricity.

Summary This study was designed to prepare environment-friendly pectin from sugar beet pulp (SBP) using subcritical water combined with ultrasonic treatment. Plackett–Burman design based on nineteen different parameters was applied to study the influence of various factors on the characteristics of sugar beet pulp pectin (SBPP). About 29.1% pectin, 62% degree of methylation (DM) and 36% acetylation (DA), and 42.5-kDa average molecular weight (AMW) were obtained from SBP when using distilled water with solid/liquid ratio of 1:81 for extraction at 110 °C. The yield of SBPP and galacturonic acid (GalA) was mainly affected by solid/liquid (S/L) ratio, water purity and extraction temperature. The ultrasonic temperature, ultrasonic power and extraction temperature were the main factors effecting on neutral sugar content, DM, DA and AMW. Compared with gum arabic (GA), the highest yield SBPP fraction had better emulsifying activity, but poorer emulsion-stabilizing ability.

A cadmium compound CdI2(phen)2, (1) (phen = 1,10-phenanthroline), was been synthesized via a hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction. The cadmium ion is coordinated by two terminal iodine ions and four nitrogen atoms from two coordinating phen molecules, constructing a distorted octahedron. Compound 1 features an isolated structure. Photoluminescent study shows that compound 1 exhibits a strong and broad emission in the blue region. Theoretical investigation reveals that the emission can be attributed to ligand to ligand charge transfer.

Two heterodimetallic complexes of formulae [LCo(AcO)2Pr(NO3)2] and [LCo(AcO)2Nd(NO3)2] (H2L=N,N'-bis(3-methoxysalicylidene) propane-1,2-diamine) have been synthesised and structurally characterised...

A zinc metalloporphyrin, ZnTCPP(acetone) (1) (TCPP = meso-tetra(4-carboxyphenyl)porphyrin), has been prepared via a solvothermal reaction and structurally characterized by single-crystal X-ray diffraction. Compound 1 features an isolated structure with a planar macrocycle and an embedded zinc ion binded to four pyrrole nitrogen atoms and one acetone oxygen atom. Photoluminescent investigation reveals that compound 1 displays an intensive emission in the red region.

Two new isonicotinic acid-containing lanthanide complexes, [Eu(HL)3(H2O)2]2n·(nH5O2)(nHgCl5)(2nHgCl4)·(2nH2O) (1) and [GdL2(H2O)4]nnCl (2) (HL = isonicotinic acid), have been synthesized via hydrot...

A novel 4f–3d metalloporphyrin, [EuZn(TPPS)H3O]n (1) (H2TPPS = tetra(4-sulfonatophenyl)porphyrin), has been synthesized via a solvothermal reaction and structurally characterized by single-crystal X-ray diffraction. Compound 1 features a three-dimensional (3-D) structure with two kinds of one-dimensional (1D) infinite chains. Based on the condensed 3-D porous open framework, compound 1 has a large void space of 223 A3, corresponding to 9.4% of the unit-cell volume. Compound 1 shows high thermal and aqueous stability. Magnetic measurements reveal that compound 1 has an antiferromagnetic behavior.

A series of novel 5-phenyl-3-(2,2′:5′,2′′-terthien-5-yl)-4,5-dihydro-1 H -pyrazolines were synthesized in this report. Their photoactivated cytotoxicities on the Spodoptera litura (SL) cell line were evaluated using the MTT method. It was noticed that the inhibitory activities of all the conjugates was enhanced when irradiated with UV-A light. Compounds 4 , 6 and 8 were found to be most effective with inhibition rates of 88.1%, 88.0%, and 90.5%, respectively. For compound 5 , the inhibition rate value was only slightly enhanced under the irradiation treatment (78.3%) compared to the dark treatment (74.8%). The relationship analysis between structure and activity showed that the middle thiophene ring played an important role on the inhibitory activities. It was shown that these compounds could be the potential candidates for new photoactivated pesticides.

Lightweight speaker-dependent (SD) automatic speech recognition (ASR) is a promising solution for the problems of possibility of disclosing personal privacy and difficulty of obtaining training material for many seldom used English words and (often non-English) names. Dynamic time warping (DTW) algorithm is the state-of-the-art algorithm for small foot-print SD ASR applications, which have limited storage space and small vocabulary. In our previous work, we have successfully developed two fast and accurate DTW variations for clean speech data. However, speech recognition in adverse conditions is still a big challenge. In order to improve recognition accuracy in noisy and bad recording conditions, such as too high or low recording volume, we introduce a novel weighted DTW method. This method defines a feature index for each time frame of training data, and then applies it to the core DTW process to tune the final alignment score. With extensive experiments on one representative SD dataset of three speakers' recordings, our method achieves better accuracy than DTW, where 0.5% relative reduction of error rate (RRER) on clean speech data and 7.5% RRER on noisy and bad recording speech data. To the best of our knowledge, our new weighted DTW is the first weighted DTW method specially designed for speech data in noisy and bad recording conditions.

Aiming at rapid-repair engineering of airport cement concrete pavement, this paper chooses rapid-hardening sulphoaluminate cement to prepare rapid-hardening sulphoaluminate concrete (RSC) and evaluate its technology performance referring to test methods of Portland cement concrete. The testing results show that RSC possesses excellent workability, good mechanical properties along with abrasion resistance, little shrinkage, and strong bonding with old pavement, which can well meets the requirements of pavement rapid restoration under the condition of not closing airport.

In this paper, the effect of fly ash with different grades and dosage on early shrinkage and late shrinkage deformation of commercial concrete were studied. The effect of fly ash with different grades and dosage on volume stability of commercial concrete was assessed by using the test method of shrinkage cracking, and the causes and mechanism of the effect were analyzed.

This paper studies the relationship of the main properties of desulphurization gypsum based inorganic thermal insulation mortar. The results show that there are different linear correlations between fresh bulk density, hardened bulk density, compressive strength, volume water absorption, thermal conductivity and dry bulk density that is from 240 kg·m-3 to 500 kg·m-3. The linear correlations can provide some useful reference for the research and application of desulphurization gypsum based inorganic thermal insulation mortar.

A novel viologen(4,4′-bipyridinium)-based compound FeCl4(4,4′-diethyl-4,4′-bipyH) (1) (bipy = bipyridine), in which 4,4′-diethyl-4,4′-bipyH (MQ +) was generated in situ, is synthesized via the hydrothermal reaction and structurally characterized by single crystal X-ray diffraction. The crystal structure analysis reveals that the title compound features an isolated structure based on 4,4′-diethyl-4,4′-bipyH moieties and an iron atom terminally bound by four chlorine atoms. The 4,4′-diethyl-4,4′-bipyH moieties and (FeCl4)− anions are interconnected by hydrogen bonds to form a 3D supramolecular framework.

To investigate the effect of confining stress, deviation stress, moisture content and gradation type on resilient modulus of graded crushed stones, three types of graded crushed stone with three moisture content levels(optimum moisture content and ±2% of the optimum moisture content, respectively ) were used, and repeated loading triaxial (RLT) tests with twenty five stress levels were carried out. The RLT test results demonstrate that resilient modulus of graded crushed stone remarkably increases with decreasing moisture content and/or increasing confining stress; resilient modulus of graded crushed stone slowly increases, or minor decreases at the beginning and then slowly increases with increasing deviation stress at low stress state. Results also indicate that gradation type has a certain impact on resilient modulus of graded crushed stone.

This article develops one new test technology, dumbbell test method, for evaluation of the early age cracking property of Concrete Material under constraint conditions. Its exercise of stress risers could lead concrete to crack quickly, providing a quick method to evaluate the early age crack performance of concrete material and to perform simulated test at job site conveniently. By this method, the anti-cracking performance of different concrete material can be evaluated quickly in the construction site.

To make clear the work mechanism of geosynthetic in asphalt overlay under the aircraft wheel loads, one 3D dimension finite element model was constructed on the basis of the general purpose finite element software ABAQUS. Numerical calculation results with different geosynthetic modulus are presented in this paper, and show that it is very limited for geosynthetic to reduce bottom stress and surface deformation of asphalt overlay, and asphalt overlay bottom is in compression state, thus, geosynthetic can not exert it’s film tension function, namely the main role of geosynthetic is not to bear loads together with asphalt overlay, but to improve stress state of asphalt overlay for preventing cracks appearance or delaying cracks expansion.

In the framework of the one-boson-exchange model, we have performed an extensive study of the possible B*, B**, D*, D** molecular states with various quantum numbers after considering the S-wave and D-wave mixing. We also discuss the possible experimental research of these interesting states.

Rosin is one of natural recycled resource which is rich in our country . Its mainly elements is tricyclic diterpenoid resin acid , rosin and disporportionated﹑hydrogenated rosin via esterification to overcome rosin itself existed many shortages,such as easy to suffer from oxidation,colour and luster unsteadiness,brittle,low softening point and expand rosin in many industry application scope . The research on rosin catalysis,esterification turning nature and the application of esterified products in the preparations of hot melt adhesives were reviewed in this paper based on the analyzing the studies in the field during the last decade, and has a prospect to the study .

According to the design theory of 3Z-II planet drive, this paper firstly design a transmission plan of a given example，then optimize the transmission plan by using the nonlinear optimization function ‘fmincon’ of MATLAB. Finally, this paper verifies the optimization result.

Stimulated by the new evidence of Y ( 4274 ) observed in the J / ψ ϕ invariant mass spectrum, we first propose the charmonium-like state Y ( 4274 ) as the S-wave D s D ¯ s 0 ( 2317 ) + h.c. molecular state with J P = 0 − , which is supported well by dynamics study of the system composed of the pseudoscalar and scalar charmed mesons. The S-wave D D ¯ 0 ( 2400 ) + h.c. molecular charmonium appears as the molecular partner of Y ( 4274 ) , which is in accord with the enhancement structure appearing at 4.2 GeV in the J / ψ ω invariant mass spectrum from B decays. Our study shows that the enhancement structures, i.e., the newly observed Y ( 4274 ) and the previously announced Y ( 4140 ) / Y ( 3930 ) in the J / ψ ϕ and J / ψ ω invariant mass spectra, can be understood well under the uniform framework of the molecular charmonium, which can be tested by future experiments.

Stimulated by recent observations of the excited bottom-strange mesons $B_{s1}$ and $B_{s2}^*$, we calculate the semileptonic decays $B_{s0}, B_{s1}^{\prime}, B_{s1}, B_{s2}^*\to [D_s(1968), D_{s}^*(2112), D_{sJ}(2317), D_{sJ}(2460)]\ell\bar{\nu}$, which is relevant for the exploration of the potential of searching these semileptonic decays in experiment., Comment: 11 pages, 3 figures, 9 tables. More discussion added, some descriptions changed. The version to appear in EPJC

Inhibitor of growth 1 (ING1) is a type II tumor suppressor that affects cell function by altering chromatin structure and regulating transcription. Recently, three ING1 splice variants have been cloned, but their roles in apoptosis and p53 regulation in human hepatocellular carcinoma (HCC) have not been fully elucidated. The present study found that ING1, in a variant-dependent manner, inhibited hepatoma cell proliferation and colony formation, induced apoptosis and cell cycle arrest at G0/G1 phase, and postponed tumor formation in nude mice. Expression of p33ING1b and p24ING1c variants, but not p47ING1a, was markedly reduced in HCC samples. Reverse transcription polymerase chain reaction and western blotting analysis revealed that ectopic overexpression of p33ING1b or p24ING1c variant increased the expression of p53 downstream genes such as p21waf1 and bax, and repressed bcl-2 expression (P < 0.01), whereas p47ING1a inactivated p21waf1 promoter (P < 0.01). Furthermore, we found that p33ING1b and p24ING1c repressed Mdm2 expression (P < 0.01) and competed with Mdm2 for binding to p53. Interestingly, p33ING1band p24ING1c did not directly bind to Mdm2 protein but strongly increased p14arf expression (P < 0.01) and interacted with p14arf protein to stimulate p53. Moreover, we found that ectopic overexpression of p33ING1b or p24ING1c significantly induced p53 protein acetylation at Lys-373/Lys-382 residue, but did not alter the phosphorylation status of p53. Conclusion: ING1 variants p33ING1b and p24ING1c may modulate p53 activity and subsequently inhibit hepatoma cell growth by at least two possible mechanisms: interacting with Mdm2 and p14arf to stabilize and activate p53, or increasing p53 acetylation. (HEPATOLOGY 2009.)

The metalloporphyrin [(ZnTPP)2( μ2-4,4'-bipy)], (H2TPP = 5,10,15,20-tetraphenyl-21H,23H-porphyrin; 4,4'-bipy = 4,4'-bipyridine), has been synthesised via a solvothermal reaction and structurally characterised by single-crystal X-ray diffraction. It features a planar porphyrin macrocycle and an embedded ZnII ion coordinating to four pyrrole nitrogen atoms and one 4,4'-bipy nitrogen atom. A photoluminescent and theoretical study shows that the complex exhibits an emission in the red region, attributed to ligand to ligand charge-transfer.

A novel iron porphyrin [FeTCPP] n [TCPP = meso-tetra(4-carboxyphenyl)porphyrin] has been synthesised via a hydrothermal reaction and structurally characterised. It has a two-dimensional structure and is thermally stable up to 320°C. UV–Vis, FT–IR and fluorescence data are also reported. Porphyrins have interesting roles in nature such as in green leaves and red blood cells, as well as applications in medicine, catalysis, optics, conductive materials, magnetism and solar energy conversion.

The first crystalline TPPS complex [Zn(en)TPPS][Zn(en)3] (where en is ethylenediamine and TPPS is tetraphenylporphyrin tetrasulfonic acid) has been synthesised via a solvothermal reaction and structurally characterised by a single-crystal X-ray diffraction. Zn(en)TPPS][Zn(en)3has discrete [Zn(en)TPPS]2–and [Zn(en)3]2+moieties, which are interconnected via hydrogen bonds to form a three-dimensional supramolecular framework that possesses a large void space (1507.6 Å3) corresponding to 22.5% of the unit-cell volume. The UV-Vis spectrum and photoluminescence have also been studied in detail.

A novel N,N'-diethyl-4,4'-bipyridine copper complex, [Cu2Cl4][(C2H5)2-4,4'-bipyridine] (1), has been obtained in situ through a solvothermal reaction and structurally characterised by X-ray diffraction. Complex 1 comprises discrete Cu2Cl4 moieties and (C2H5)2-4,4'-bipyridine molecules interlinked via hydrogen bonding interactions to give a three-dimensional supramolecular open framework. Photoluminescent study shows that the complex exhibits an emission in the green region. Theoretical study reveals that the emission is attributed to the π → π* charge-transfer interaction of the (C2H5)2-4,4'-bipyridine moieties.

This study was conducted to demonstrate myocardial protective effects and possible underlying mechanisms of vitexin on myocardial ischemia/reperfusion (I/R) injury in rats. Occluding the anterior descending artery for 30 min and restoring blood perfusion for 60 min in rat established a model of myocardial I/R. The elevation of the ST segment of Electrocardiograph (ECG) was observed. The infarct size of the rat heart was assessed by triphenyltetrazolium chloride staining (TTC). LDH, CK, SOD activities and MDA content were determined. An immunohistochemical analysis was applied to measure the expression of myocardial NF-κBp65 and TNF-α. ERK/phospho-ERKand c-Jun/phospho-c-Jun protein expression was examined via Western Blot. Vitexin significantly reduced the elevation of the ST segment of ECG and myocardial infarct size. LDH and CK activities and MDA content were attenuated in serum, while SOD activity was markedly enhanced. Vitexin significantly attenuated I/R-induced increases of myocardial NF-κB and TNF-α. Moreover, Western Blot analysis presented that vitexin markedly enhanced the expression of phospho-ERK and weakened the expression of phospho-c-Jun compared to I/R group. The significant protective effect against myocardial ischemical/reperfusion injury in rat, which is exhibited by vitexin, may be related to its antioxidative and anti-inflammatory effects by regulating inflammatory cytokines and the MAPK pathway.

A novel terbium-containing fluorescent material, [Tb(CH3COO)2(H2O)3]Cl (1), has been prepared by a facile approach, i.e. an ultrasonic synthesis. Compound 1 has been structurally characterized via single-crystal X-ray diffraction and it crystallizes in the space group P21/n of the monoclinic system with four formula units in a cell. Compound 1 features a novel one-dimensional (1-D) chain-like structure. The 1-D chains are interconnected by hydrogen bonds to yield a 3-D supramolecular framework. Photoluminescent investigation reveals that compound 1 displays strong emission bands identified as the characteristic emissions of 5D4 → 7FJ (J = 3, 4, 5, 6) of Tb3+.

The primary objective of this study was to determine the effect of asphalt structure patterns on permanent deformation, and investigate the contribution of pavement structural layers to permanent deformation of asphalt pavement. Three test segments were constructed at the Circular Track in Chongqing. The three segments had a similar HMA wearing course, binder course, and sub-grade. However, the base course and sub-base of the three segments were different, and the total depth of asphalt layers was different. All three segments were tested under the Accelerated Loading Facility to 500 thousand passes. The permanent deformation was evaluated using rutting measurements. The test results showed that the majority of permanent deformation occurred in top 200mm of the asphalt layer and the maximum cumulative deformation rate occurred within 120mm depth, which may indicate that the binder course significantly influenced permanent deformation of asphalt pavements.