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Four flavones (flavone, 7-hydroxyflavone, chrysin, and baicalein) sharing the same B- and C-ring structure but a different numbers of hydroxyl groups on the A-ring were studied for their affinities for BSA and HSA. The hydroxylation on ring A of flavones increased the binding constants (K(a)) and the number of binding sites (n) between flavones and serum albumins. The affinities of 7-hydroxyflavone for BSA and HSA were about 800 times and 40 times higher than that of flavone, respectively. It appears that the optimal number of hydroxyl groups introduced to the ring A of flavones is one. As more hydroxyl groups were introduced to positions at C-5, C-6, and/or C-7 of flavones, the affinities for serum albumins decrease. The critical energy transfer distances (R(0)) between the hydroxylated flavones (1-3 OH on the ring A) and serum albumins decreased with the increasing affinities for serum albumins.

A direct procedure for the determination of total polysaccharides (TPS) in Camellia sinensis was set up based on the modified phenol-sulfuric acid method. The monosaccharide composition of TPS was analyzed by GC. Based on the results of GC, model monosaccharide mixtures were made which provided an adequate standard for this procedure. Through single-factor and orthogonal (L934) experiments, the experimental conditions such as the volume of phenol, the volume of concentrated sulfuric acid, the reaction time, and the incubation temperature, were optimized. The highest sensitivity of absorbance was obtained when the volume of concentrated sulfuric acid, the volume of phenol (6%), and the incubation temperature were 2.5 ml, 0.2 ml, and 50?C, respectively. Under optimum conditions, the prepared samples were determined satisfactorily, with the recovery from 100.2% to 103.7%, and a relative standard deviation (RSD) of 2.1%. Overall, the modified method is easily operated, rapid, sensitive and accurate. A similar procedure can be applied to the determination of other plant polysaccharides as well. .

The effects of different extraction methods on the composition and bioactivity of tea flower polysaccharides (TFPS) were investigated. Traditional water extraction (TWE), microwave-assisted water extraction (MAE), and ultrasound-assisted water extraction (UAE) were compared to extract TFPS. TWE was found to be the optimal method with highest yield of TFPS and highest neutral and acid saccharides contents in TFPS. TFPS obtained by TWE mainly consisted of two kinds of polysaccharides with the molecular weight of 31 kDa and 5000 Da. TFPS obtained by MAE and UAE generally had very low inhibitory effects on α-glucosidase. TFPS (2 mg/mL) obtained by TWE exhibited a strong inhibitory effect on α-glucosidase with the inhibitory rate of 83.3%. TFPS obtained by TWE had stronger proliferation effect on lymphocyte at the concentration of 3.0 μg/mL than that of tea leave polysaccharides (TPS).

There are several models by means of quenching fluorescence of BSA to determine the binding parameters. The binding parameters obtained from different models are quite different from each other. Which model is suitable to study the interaction between trans-resveratrol and BSA? Herein, twelve models based fluorescence quenching of BSA were compared. The number of binding sites increasing with increased binding constant for similar compounds binding to BSA maybe one approach to resolve this question. For example, here eleven flavonoids were tested to illustrate that the double logarithm regression curve is suitable to study binding polyphenols to BSA.

Many emerging interfacial technologies, such as self-cleaning surfaces, oil/water separation, water collection, and microfluidics, are essentially liquid manipulation processes. In this regard, micro-nanostructures of the living organisms are highly preferable, by virtue of the evolutionary pressure and the adaptation to the specific environments, to inspire the optimization of man-made interfaces. With the increasing demands of modern life, research, and industry, intelligent materials with stimuli-responsive liquid manipulation functions have gained substantial attention from interfacial scientists. This review introduces the recent progress in the development of stimuli-responsive liquid-manipulating materials with bioinspired structures and surface chemistry according to two classified manipulation modes: (i) smart manipulation of liquid wetting behaviors, including lyophobic/lyophilic and superlyophobic/superlyophilic, and (ii) smart manipulation of liquid motion behaviors, including coalescence, transportation, rolling/adhesion, and sliding/pinning. At the beginning of the presentation of each classification, the theoretical basis and the sources of inspiration are introduced comprehensively to ensure a better understanding. This review mainly focuses on the mechanisms, fabrication, and applications of the state-of-the-art works related to smart and biomimetic liquid-manipulating materials. Finally, conclusions and future prospects are provided, and the remaining problems and promising breakthroughs in fabricating large-scale, cost-effective, and efficient smart liquid-manipulating materials are outlined.

The protective effects of tea polysaccharides (TPS) and polyphenols (TPP) on skin were investigated. TPS1 (92% TPS), crude TPS2 (20% TPS), and TPP (98%) were tested. The abilities of TPS and TPP to protect the skin were assessed in four aspects: moisture absorption and retention, sunscreen, promoting the proliferation of fibroblast cells, and tyrosinase inhibitory effect. TPS and TPP absorbed and reserved moisture perfectly. TPS with higher purity had better moisture absorption and retention abilities. TPS1 hardly protected the skin from the sun's ultraviolet (UV) rays and had little promoting effect on fibroblasts proliferation. TPP, however, protected skin against UV rays and enhanced proliferation of fibroblast cells significantly. TPP had good tyrosinase inhibitory effects; TPS showed weaker tyrosinase inhibitory effects with the purity increased. The results indicated that TPP and TPS had complementary advantages and they should be appropriately combined to achieve higher performance when applied as active components of cosmetics.

Effects of chitosan pentamer ((GLcN)5) and chitosan hexamer ((GLcN)6) in vivo and in vitro on gene transcription and protein translation of interleukin-1 (IL-1), tumour necrosis, factor alpha (TNF-α), interleukin-2 and interferon-γ (IFN-γ) were investigated by relatively quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. The results showed that the expression of IL-1 mRNA, TNF-α mRNA, IFN-γ mRNA as well as the secretion of IL-1, TNF-α and IFN-γ can both be promoted by (GLcN)6 and (GLcN)5. The promotion effects caused by (GLcN)6 were greater than that of (GLcN)5. Gene transcription and protein secretion of cytokines were promoted by (GLcN)5 and (GLcN)6 in vivo and in vitro and thus the immuno-modulating ability was promoted. This may be one of the molecular mechanisms for elucidation of immunity of chitooligosaccharides.

A continuous adsorption study in a fixed-bed column was carried out by using phoenix tree leaf powder as an adsorbent for the removal of methylene blue (MB) from aqueous solution. The effect of flow rate, influent MB concentration and bed depth on the adsorption characteristics of adsorbent was investigated at pH 7.4. Data confirmed that the breakthrough curves were dependent on flow rate, initial concentration of dye and bed depth. Four kinetic models, Thomas, Adams–Bohart, Yoon–Nelson and Clark, were applied to experimental data to predict the breakthrough curves using nonlinear regression and to determine the characteristic parameters of the column that are useful for process design, while a bed-depth service time analysis (BDST) model was used to express the effect of bed depth on breakthrough curves and to predict the time needed for breakthrough at other conditions. The Thomas and Clark models were found suitable for the description of whole breakthrough curve, while the Adams–Bohart model was only used to predict the initial part of the dynamic process. The data were in good agreement with the BDST model. It was concluded that the leaf powder column can be used in wastewater treatment.

The interaction between flavonoids and proteins has attracted great interest among researchers. However, few reports have focused on the structure-affinity relationship of flavonoids binding to proteins. This work mainly concerns the effect of glycosylation of flavonoids on the affinities for BSA. Four flavonoid aglycones (baicalein, quercetin, daidzein, and genistein) and their monoglycosides (baicalin, quercitrin, daidzin, and puerarin, genistin) and another poly glycoside (rutin) are studied for their affinities for BSA. The glycosylation of flavonoids significantly affects the quenching/binding process. In general, the glycosylation of flavonoids lowers the affinity for BSA by 1 to 3 orders of magnitude depending on the conjugation site and the class of sugar moiety. The glucopyranosylation (daidzin and genistin) of flavonoids lowered the affinity for BSA by 5-10 times. Rhamnosylation (quercitrin) of flavonoids, however, lowered the affinity for BSA by 5600 times. This result partly supports that flavonoid aglycones are more easily absorbed than flavonoid glycosides. Higher binding affinities for BSA are associated with higher antioxidant activities for flavonoids. Glycosylation also decreases the hydrophobicity of flavonoids, and hydrophobic interaction may play an important role in binding flavonoids to proteins.

A neutral polysaccharide, coded as NTPS-1, was obtained from the crude tea polysaccharide (NTPS) of green tea ( Camellia sinesis ) by a DEAE-Sepharose fast flow column. The polysaccharide appeared to be homogenous with the weight of 21,247 Da by the high performance gel permeation chromatography (HPGPC) analysis. The NTPS-1 was found to consist of galactose. The structure of NTPS-1 was characterized by infrared (IR) spectrum, gas chromatography (GC), periodate oxidation, Smith degradation, 1D NMR and 2D NMR spectroscopy. It was found that NTPS-1 was a galactan consisting of β-(1→4)-linked galactopyranosyl units.

Adsorption equilibrium and kinetic of methylene blue (MB) onto natural zeolite was studied in a batch system. Variables of the system include contact time, pH, salt concentration, temperature, and initial MB concentration. The increase in temperature resulted in a higher MB loading per unit weight of the zeolite. Langmuir, Freundlich, Redlich–Peterson, Koble–Corrigan and Temkin isotherm models were applied to experimental equilibrium data of MB adsorption depending on temperature. The effect of contact time at different temperatures and initial concentration were fitted to pseudo-second-order kinetic model. Linear regressive method and nonlinear regressive method were used to obtain the relative parameters. The error analysis was conducted to find whether linear method or nonlinear method was better to predict the experimental results and which model was better to fit the experimental data. Both methods were suitable to obtain the parameters. The Redlich–Peterson equation was best to fit the equilibrium data. The pseudo-second-order kinetic model can be used to describe the adsorption behavior. The nonlinear method may be better with the absolute error as limited condition. The adsorption process was spontaneous and endothermic.

A reversed-phase liquid chromatographic method was developed for the quantitative determination of three major hypotensive compounds, namely geniposidic acid, chlorogenic acid, and geniposide in the bark of Eucommia ulmoides. Soxhlet extraction of GPA, GPS, and CA from E. ulmoides was optimized according to the Taguchi experimental design. Maximum global yields were obtained using the following conditions: extraction temperature, 80?C; extraction time, 1 h; number of extractions, three; solvent volume, 16 ml/g of sample; and 50% ethanol concentration in water. Optimal conditions of separation and detection were achieved on a Diamonsil ODS C18 column (150 mm ? 4.6 mm, 5 ?m) with a linear gradient of methanol and 0.04% aqueous phosphoric acid (v/v) at a flow rate of 1.0 ml/min and detection wavelength of 240 nm. All calibration curves showed good linearity (r2 > 0.999) within test ranges. The relative deviation of this method was less than 3% for intra- and inter-day assays, and the recovery percentage of the method was 95-104%, with a relative standard deviation (R.S.D.) of less than 5%. The current assay method was used for quantitative determination of geniposidic acid, chlorogenic acid, and geniposide in five samples of E. ulmoides with different age. The results indicate that the developed method could be readily utilized as a quality control method in working with E. ulmoides.

Uniform and well-dispersed photoluminescent semiconductor CdS (cadmium sulfide) QDs (quantum dots) were in situ prepared inside Generation 4.0-NH 2 PAMAM (polyamidoamine) dendrimers in methanol, methanol and water mixed solutions of volume ratio 1:9, respectively. The prepared solutions containing photoluminescent semiconductor CdS QDs were utilized for detection of cyanoacrylate ester fumed fingerprints on tinfoil. The results show that fumed latent fingerprints treated with prepared CdS/PAMAM nanocomposites in methanol, 1:9 methanol:water mixed solutions emit pale yellow–green and orange luminescence respectively under ultraviolet excitation of 365 nm from an UV LED. Fumed fingerprints were successfully detected with good resolving rate and the mechanism was studied in detail.

Comparison analysis of linear least square method and nonlinear least square method for estimating the kinetic parameters was made using the experimental column data of methylene blue (MB) adsorption onto zeolite at different flow rates and initial concentration. The data were fitted to Thomas model equations using linear and nonlinear regressive analysis, respectively. The error analysis was performed. Present investigation showed that the linear and nonlinear methods are both suitable to predict the breakthrough curves using Thomas model parameters and the nonlinear method is better.

A new adsorbent, the fallen phoenix tree's leaf, has been investigated in order to remove methylene blue (MB) from aqueous solutions. Variables of the system, including contact time, leaf dose, solution pH, salt concentration and initial MB concentration, were adopted to study their effects on MB biosorption. The results showed that as the dose of leaf increased, the percentage of MB sorption increased accordingly. There was no significant difference about the quantity of MB adsorbed onto leaf as the pH was within the range 4.5-10.0. The salt concentration has negative effect on MB removal. The equilibrium data were analyzed using the Langmuir and the Freundlich isotherms. The results of non-linear regressive analysis are that the Langmuir isotherm is better fit than the Freundlich isotherm at different temperature according to the values of determined coefficients (R(2)) and chi(2)-statistic (SS). The Langmuir monolayer saturation capacities of MB adsorbed onto leaf are 80.9, 83.8, 89.7mgg(-1) at 295, 309 and 323K, respectively. Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters, such as DeltaG degrees , DeltaH degrees and DeltaS degrees , have been calculated. The thermodynamics parameters of MB/leaf system indicate spontaneous and endothermic process. It was concluded that an increase in temperature be advantage to adsorb MB onto leaf.

The quantification of damping in a structure is of significant interest in structural dynamics. At present, there is still no clear consensus on how damping issues are resolved. Although the Rayleigh damping model, which combines mass-proportional and stiffness-proportional parts, leads to reasonable engineering demand parameters of a structure within its elastic range, it does not include nonlinear response history analysis. On the other hand, a great deal of material tests demonstrate that most metallic materials under cyclic loading exhibit a stress-strain relationship that is not elastic even at stresses well below the yield point, however, the material damping effect is seldom taken into account in dynamic analysis. The present study proposes an approach that explicitly considers the additional material damping effect based on Goodman’s theory on energy dissipation of materials. The approach is applied to the nonlinear dynamic analyses of single-layer latticed domes subjected to earthquake gr...

framework, SIA, S-LCA. Abstract. Green building is becoming the main trend in current construction industry due to its main characteristics: energy saving, low carbon emission and environmental protection. Exist evaluation systems of green residential districts have little consideration on social and humanity demand. Based on the methods of social impact assessment and social life cycle assessment, and by considering the Chinese situation, an evaluation framework on the green residential districts from view of social and humanity demand was established. A series of indexes were included in this framework. An evaluation program was developed to make the evaluation more convenient. In the end, a case study was carried out to verify the effectiveness of the proposed framework and the developed program.

At present, energy saving and emission reduction have become a central task for all countries and governments, and green building has become a research hot spot at the same time. Green building is the building which maximizes the conservation of resources, protection of the environment, and realization of coordinated unification between human and nature in the whole life cycle of the building. Green building is an important embodiment of sustainable development strategy. At the beginning of the 1990s, the concept of green building was introduced to China. In recent years, in order to promote the development of green building, China issued a series of related approaches and normative documents, such as Evaluation Standard for Green Building (GB/T50378-2006). Recently, in order to improve the green building standard, the Ministry of Housing and Urban Construction gives out the announcement, approving the Evaluation Standard for Green Building as the national standard, numbered GB/T50378-2014. The US Green Building Rating System (LEED) is now considered to be the most sophisticated and influential among all kinds of environmental protection assessments. In the revision of the Evaluation Standard for Green Building, certain aspects of LEED were consulted, so there is similarity between the two standards. But Evaluation Standard for Green Building also has its own characteristics based on China’s conditions. So this chapter pays attention to the comparison of the Evaluation Standard for Green Building (the latest revision), Evaluation Standard for Green Building (GB/T50378-2006), and US LEED standards. It uses the following eight aspects: evaluation phase, evaluation objects, index categories, refined indicators, scoring points, evaluation methods, evaluation results, and weight distribution to show the similarities and differences among the three standards. And it can point out the advantages and shortcomings of Evaluation Standard for Green Building in China and makes reasonable suggestions.

Se-polysaccharides from Se-enriched tea leaves were purified by DEAE-sepharose fast flow gel column (2.5×60cm) and three polysaccharide fractions (Se-TPS1, Se-TPS2, and Se-TPS3) were isolated and purified with yields of 6.5, 37.14, and 8.57%, respectively. The average sizes of Se-TPS1 and Se-TPS2 were determined by HPGPC system, with molecular weights of 1.1×10(5) and 2.4×10(5)Da, respectively. Se-TPS3 was a polysaccharide polymer with two peaks with molecular weights of 9.2×10(5) and 2.5×10(5)Da. Monosaccharide components analysis by ion chromatography revealed Se-polysaccharides were acidic polysaccharoses and different from each other in monosaccharide kinds and molar ratio. Elements of Se, C, H, N, S, and 14 kinds of mineral elements were analyzed by AFS, EA, and ICP-AES, respectively. Spectral analysis (IR and UV) indicated Se-polysaccharides were typical glycoproteins. Morphological analyses of the samples were determined by SEM and AFM. In addition, the DPPH and superoxide radicals scavenging activities were also discussed to assess antioxidant activities of the samples, and Se-polysaccharides showed higher antioxidant activities compared to the ordinary polysaccharides.

We study the thermal entanglement in the two-qubit XY model with magnetic fields in x–y plane. For the anisotropic XY model with uniform fields, we find that the entanglement of system exhibits different behaviors with the change of field directions at different field strength. For the isotropic XY model with nonuniform field, we find that the entanglement and limit temperature of system may be increased by tuning the relative angle between two local magnetic fields.

Four polysaccharides (TPS-F, TPS-V, TPS-S and TPS-M) were obtained from tea (Camellia sinensis) leaves by freeze-drying, vacuum-drying, spray-drying and microwave-vacuum drying, respectively. Their chemical composition and biological properties were comparatively studied. The results showed these TPS were similar in IR, UV absorption and distribution of molecular weight. However, they showed significant differences (P0.05) in yields of crude polysaccharides and contents of protein and total polyphenols. Furthermore, morphological analysis showed their surface differed from each other in size and shape when viewed by SEM, from which surface of TPS-F was rough and porous, surface of TPS-S was evenly particles, and surfaces of the other two were similar to anomalistic bricks. In addition, the bioactivity of them was also evaluated. It was found TPS-F exhibited relatively better ability on metal chelating and superoxide radicals scavenging assays than others, and TPS-V exhibited higher ability on α-glycosidase and α-amylase inhibition assays than others with inhibitory percentages of 82.75% and 92.8%.

New biological techniques and technological advances in high-throughput sequencing are paving the way for systematic, comprehensive annotation of many genomes, allowing differences between cell types or between disease/normal tissues to be determined with unprecedented breadth. Epigenetic modifications have been shown to exhibit rich diversity between cell types, correlate tightly with cell-type specific gene expression, and changes in epigenetic modifications have been implicated in several diseases. Previous attempts to understand chromatin state have focused on identifying combinations of epigenetic modification, but in cases of multiple cell types, have not considered the lineage of the cells in question. We present a Bayesian network that uses epigenetic modifications to simultaneously model 1) chromatin mark combinations that give rise to different chromatin states and 2) propensities for transitions between chromatin states through differentiation or disease progression. We apply our model to a recent dataset of histone modifications, covering nine human cell types with nine epigenetic modifications measured for each. Since exact inference in this model is intractable for all the scale of the datasets, we develop several variational approximations and explore their accuracy. Our method exhibits several desirable features including improved accuracy of inferring chromatin states, improved handling of missing data, and linear scaling with dataset size. The source code for our model is available at http://github.com/uci-cbcl/tree-hmm

A one-step strategy for the facile synthesis of polyethyleneimine-functionalized Fe3O4 (Fe3O4-PEI) composite is presented in this study. We also investigated the effects of reaction time and NaAc on the composite sizes. The composite with good dispersion, wonderful crystallization, and excellent magnetism was obtained through one-pot solvothermal reaction. In the sequential presence of PEI and colloidal gold (Au) solution, plentiful Au nanoparticles with a diameter of 5 nm were assembled on the surface of Fe3O4–PEI to get Fe3O4–PEI–Au1–PEI–Au2 (Fe3O4/Au) composite. In-depth characterization of the composite formation process was performed using transmission electron microscopy, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, and UV–Visible spectroscopy. The Fe3O4/Au composite was obtained with an average diameter of 150 nm, and the absorption peak was red-shifted to 580 nm. The synthesized Fe3O4/Au composite, the saturation magnetization of which was 40.4 emu/g, presented good magnetic property. Moreover, the composite could easily combine with up to 890 μg antibodies per mg, and the antibodies still kept good immunocompetence after immobilization. These advantages suggest its great potential for applications in vitro, such as separation and immunoassay.

We establish new oscillation and nonoscillation theorems for the second order quasilinear dynamic equation (r(t)|y^{\Delta}(t)|^{\alpha-1}y^{\Delta}(t))^{\Delta}+f(t,y^{\sigma}(t))=0 ¶ on a time scale $\T$. Our results not only extend the results given in J. Wang, "On second order quasilinear oscillations," Funkcialaj Ekvacioj, 41 (1998), 25-54, but also unify the oscillation and nonoscillation criteria for second order quasilinear differential equations and difference equations.

An improved thermal decomposition method was used to directly prepare water-soluble Fe3O4 magnetic nanoparticles (MNPs) with relatively higher quality via reductive decomposition of ferric acetylacetonate [Fe(acac)3], in the presence of benzyl ether and phenol, in which inexpensive phenol acted as reducing agent and stabilizer, produce the semi phenol-benzoquinone coated on the Fe3O4 and make the Fe3O4·MNPs water-soluble and the colloidal solution stable. By changing the molar ratio of phenol to Fe(acac)3 and reaction time, the size of Fe3O4·MNPs could be varied from 19.3 ± 4.4 nm to 9.7 ± 1.5 nm, with the saturation magnetizations in the range of 51.3–62.9 emu/g.

A novel polypropylene/Polyhedral oligomeric silsesquioxanes (PP/POSS) composite unwoven fabric with permanent electret was prepared through melt-blown process with corona charging. Field-emission scanning electron microscope (FESEM) and wide-angle X-ray diffraction (WAXRD) were employed to investigate the morphology of the composite fibers and the distribution of POSS nanoparticles on the surface of the fibers, respectively. POSS acted as nucleating agent and accelerated the crystallization process during nonisothermal cooling. The utmost stable charge density of PP/POSS melt-blown unwoven fabric was improved by 78.4% compared with the neat PP unwoven fabric. The maximum value of collection efficiency measured by monodisperse polystyrene aerosol (PSL) (particle size: 0.3 μm) collection could reach 97.36% for PP/POSS composite melt-blown unwoven fabric, which improved by 9% compared with neat PP melt-blown unwoven fabric. Moreover, both stress and elongation at break of the PP/POSS melt-blown unwoven fabrics were improved compared with PP unwoven fabric.

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This paper investigates the effect of various material and geometric parameters on the creep of axially loaded fiber-wrapped high-strength concrete column (FWHSCC). For this purpose, a total of twenty-eight FWHSCCs, classified into nine groups, with different intrinsic factors such as the type and amount of fiber reinforced polymer (FRP), the creep of FRP, the water-cement ratio, the aggregate-cement ratio, the silica fume content and the compressive strength of high-strength concrete (HSC) core, and extrinsic factors including the level of loads applied to columns and the radius of column section, were analyzed by the model for predicting the creep of FWHSCC. The results of this parametric study indicate that the creep of FWHSCC is mainly affected by the composition and compressive strength of the concrete core, while the others only have slight influence on the compliance function of creep of FWHSCC.

Effective virtual screening relies on our ability to make accurate prediction of protein-ligand binding, which remains a great challenge. In this work, utilizing the molecular-mechanics Poisson-Boltzmann (or Generalized Born) surface area approach, we have evaluated the binding affinity of a set of 156 ligands to seven families of proteins, trypsin β, thrombin α, cyclin-dependent kinase (CDK), cAMP-dependent kinase (PKA), urokinase-type plasminogen activator, β-glucosidase A, and coagulation factor Xa. The effect of protein dielectric constant in the implicit-solvent model on the binding free energy calculation is shown to be important. The statistical correlations between the binding energy calculated from the implicit-solvent approach and experimental free energy are in the range of 0.56-0.79 across all the families. This performance is better than that of typical docking programs especially given that the latter is directly trained using known binding data whereas the molecular mechanics is based on general physical parameters. Estimation of entropic contribution remains the barrier to accurate free energy calculation. We show that the traditional rigid rotor harmonic oscillator approximation is unable to improve the binding free energy prediction. Inclusion of conformational restriction seems to be promising but requires further investigation. On the other hand, our preliminary study suggests that implicit-solvent based alchemical perturbation, which offers explicit sampling of configuration entropy, can be a viable approach to significantly improve the prediction of binding free energy. Overall, the molecular mechanics approach has the potential for medium to high-throughput computational drug discovery.

Based on the characteristics of concrete sulfate attack, a two-dimension cellular automata model is developed based on the fundamental theory of cellular automata to simulate the penetration process of sulfate ion in concrete under sulfate attack. The evolution rules of the cellular automata model are validated by comparison with the calculation results from the Fick's second law. Meanwhile, it discusses the essential distinction between the cellular automata model and the Fick's second law in calculation method and characteristics of the sulfate ion corrosion in concrete. By further analysis of the characteristics of sulfate ion's diffusion in different corrosion time in concrete, the calculated results derived from the cellular automata model, in which the changes of sulfate ion's jump probabilities are taken into account, show better correlation with the experimental data than that from the Fick's second law, thereby a new approach is provided for analysis of concrete durability.

The sugar compositions, α-glucosidase inhibitory and α-amylase inhibitory activities of polysaccharides from leaves and flowers of green tea (Camellia sinensis) obtained by hot water extraction (HWE), boiled water extraction (BWE) and enzymatic extraction (EE) were investigated. The yields, sugar contents and monosaccharide compositions of tea leaves polysaccharides (TLPS) and tea flower polysaccharides (TFPS) were all significantly affected by extraction methods. The contents of acidic polysaccharides (APS) extracted by BWE and EE were both much more than those by HWE. The yields of TLPS and TFPS were determined as EE > BWE > HWE. Enzyme and higher temperature could improve the contents of APS and yields of TLPS and TFPS. TLPS and TFPS were all mainly composed of Rha, Ara, Gal, Glu and GalA, very little molar contents of GluA, Xyl and Man. It seemed that enzyme extraction could be more conducive to increase the content of Ara, Gal and GaLA. The molecular weights of TFPS were larger than those of TLPS. The molecular weights of polysaccharides obtained by EE decreased. Proteins in tea leaves and tea flowers might be decomposed by EE by observing UV peaks and IR absorption. peaks. The α-glucosidase inhibitory and amylase inhibitory activities of TLPS and TFPS obtained by EE were lower than those by water extracted method. The inhibitory percentages of TLPS and TFPS against α-amylase were all lower than α-glucosidase for different extractions.

The effect of solution temperature and the determination of the kinetic parameters of methylene blue (MB) adsorption onto cereal chaff were performed to understand the adsorption mechanism. The pseudo-second order kinetic model was fitted to the experimental data and found it was good to predict the adsorption behavior using nonlinear regressive method, suggesting that the mechanism may be a chemisorption process. The activation energy of adsorption (Ea) was 22.4 kJ mol-1. The thermodynamic parameters (ΔG0, ΔH0, and ΔS0) were also determined from the temperature dependence. The results showed that the process of adsorption MB was spontaneous and endothermic process and an increase in temperature favored the adsorption. The diffusion coefficient was also estimated.

Neutral polysaccharides (NTPS) and acid polysaccharides (ATPS) from tea leaves were obtained on a D315 macroporous anion-exchange resin column chromatography. NTPS and ATPS were sulfated by the pyridine–sulfonic acid method to obtain NTPS-S and ATPS-S. It was found that NTPS was easier sulfated than ATPS. There are strong characteristic absorption peaks located in 1258 cm −1 , 1146 cm −1 , 832 cm −1 and 617 cm −1 in the FTIR spectra of sulfated polysaccharides. Sulfation of polysaccharides also affected the endothermic and exothermic peaks via the DSC scan analysis. The appearance of exothermic peaks in both NTPS-S and ATPS-S indicated that the redox reaction might happen. The comparative study of hypoglycemic effect on mice showed that the sulfation of polysaccharides significantly improved hypoglycemic activity.

Chitooligosaccharides were prepared through hydrolysis of colloidal chitosan by enzyme source from Aspergillusfumigatus BSF114. Chitosan pentamer (COS5) and chitosan hexamer (COS6) were isolated and purified from COS by the ultra-filtration, nano-filtration, ethanol precipitation and the CM-Sephadex C-25 column. COS5 consisted of (GlcN)4 (59.84%) and (GLcN)5 (40.16%). COS6, however, mainly consisted of (GLcN)6 (93.11%) and (GLcN)(5) (6.89%). Effects of COS5 and COS6 in vivo and in vitro on gene expression of cell surface CR3 receptor were investigated by relatively quantitative RT-PCR and ELISA. The results showed that the expression of CR3 mRNA could be promoted by both COS5 and COS6. The promotion effect caused by COS6 was greater than that of COS5.

The interaction between esculin and serum albumins was investigated to illustrate that the fluorescence resonance energy-transfer (FRET) affects the determination of the binding constants obtained by fluorescence quenching method. The binding constants (K(a)) obtained by the double-logarithm curve for esculin-BSA and esculin-HSA were 1.02x10(7) and 2.07x10(4)L/mol, respectively. These results from synchronous fluorescence showed that the Tyr and Trp residues of HSA were affected more deeply than those in BSA. The excitation profile of esculin showed that in the presence of BSA and HSA, the S(0)-->S(1) transition of esculin (lambda(ex)(max) approximately 340nm) appears, which is similar to the lambda(em)(max) of BSA and HSA. The critical distance (R(0)) between BSA and esculin is higher than that of HSA, which showed that the affinity of esculin and HSA should be higher than that of BSA. After centrifugation, the concentrations of esculin bound to albumins were determined by means of the fluorescence of esculin. It was found that much more esculin was bound to HSA than to BSA. However, the bound models for BSA and HSA are almost the same. The concentration of esculin bound to serum albumin at first decreased with the addition of esculin and then increased. From above results, it can be concluded that the affinity of esculin and HSA should be higher than that of esculin and BSA. This example showed that in the presence of FRET, the binding constants between ligands and proteins based on fluorescence quenching might be deviated.

An acidic polysaccharide (ATPS-2) was isolated and purified from coarse green tea. ATPS-2 with peak molecular weight of 4430 Da was composed of rhamnose, arabinose, galactose and galacturonic acid. Structure features of the purified ATPS-2 were investigated by a combination of chemical and instrumental analysis, such as periodate oxidation, Smith degradation, (1)H NMR, (13)C NMR, COSY, HSQC, HMBC and ROESY spectrum. It was found that ATPS-2 was a pectic polysaccharide. The backbone proved to consist of the smooth region of alpha-1,4-D-galactopyranosyluronan blocks interconnected by 1,2-linked rhamnose residues involved in the linear sugar chain. The ramified hairy regions were shown to contain the following of the backbone: -->4)-alpha-D-GalpA-(1 --> 2)-alpha-L-Rhap-(1 --> 4)alpha-D-GalpA-(1--> and the side chains attached to the residues of rhamnopyranose of these fragments. The backbone galacturonic acid residues of ATPS-2 were partially O-methyl esterified and acetylated. The side chains contain linear and branched alpha-L-Araf and beta-D-Galp residues.

Nanometer-sized fluorescent particles were synthesized in an aqueous solution using TGA (mercaptoacetic acid) as the stabilizer. The prepared solution was characterized by fluorescence spectroscopy and applied for detection of latent fingermarks on adhesives. The effects of stabilizer, precursor, pH value, the concentration of cadmium ion and shell structure on fluorescence were also discussed. The results indicated that the intensity of fluorescence was remarkably increased and the selectivity was well improved when using CdSe nanoparticles, it produced significantly less background development and better contrast after 15 min developing process.

Traces of 13 blue roller-ball pen inks were identified by high performance capillary electrophoresis (HPCE) with 0.03 mol/L borate and 10% (in volume) methanol as buffer at the voltage of 15 kV and the temperature of 25 degrees C. Samples could be classified into 3 major groups and 5 subgroups by UV detection results and 4 species by visible detection results. The analytical results with different wavelength lights could be used to cross confirm the ink species. The aging effect was studied for 3 samples stored in darkness, and the relative ages were determined based on the relative quantities of some components. In addition, no effect of the matrix of paper was found on the results.

A continuous fixed bed study was carried out by using rice husk as a biosorbent for the removal of congo red (CR) from aqueous solution. The effects of important factors, such as the value of initial pH, existing salt, the flow rate, the influent concentration of CR and bed depth, were studied. Data confirmed that the breakthrough curves were dependent on flow rate, initial dye concentration and bed depth. Thomas, Adams-Bohart, and Yoon-Nelson models were applied to experimental data to predict the breakthrough curves using non-linear regression and to determine the characteristic parameters of the column useful for process design, while bed depth/service time analysis (BDST) model was used to express the effect of bed depth on breakthrough curves. The results showed that Thomas model was found suitable for the normal description of breakthrough curve at the experimental condition, while Adams-Bohart model was only for a initial part of dynamic behavior of the rice husk column. The data were in good agreement with BDST model. It was concluded that the rice husk column can remove CR from solution.

In this study, the ability of rice husk to adsorb methylene blue (MB) from aqueous solution was investigated in a fixed-bed column. The effects of important parameters, such as the value of initial pH, existed salt, the flow rate, the influent concentration of MB and bed depth, were studied. The Thomas model was applied to adsorption of MB at different flow rate, influent concentration and bed depth to predict the breakthrough curves and to determine the characteristic parameters of the column useful for process design using non-linear regression. The bed-depth/service time analysis (BDST) model was also applied at different bed depth to predict the breakthrough curves. The two models were found suitable for describing the biosorption process of the dynamic behavior of the rice husk column. All the results suggested that rice husk as adsorbent to removal MB from solution be efficient, and the rate of biosorption process be rapid. When the flow rate was 8.2ml min(-1) and the influent concentration of MB was 50mgl(-1), the equilibrium adsorption biomass reached 4.41mgg(-1) according to Thomas model.

A new adsorbent system for removing methylene blue (MB) from aqueous solutions has been investigated. This new adsorbent is cereal chaff, an agriculture product in middle-west region in China. Variables of the system, including biosorption time, chaff dose, pH, salt concentration and initial MB concentration, were adopted to study their effects on MB removal. The results showed that as the dose of chaff increased, the percentage of MB sorption increased accordingly. There was no significant difference in the dye concentration remaining when the pH was increased from 4.0 to 11.0. The salt concentration has negative effect on MB removal. At the experimental range of MB concentration, the amount of MB adsorbed onto per unit mass of chaff ( q e ) is direct ratio to MB initial concentration ( c 0 ). The equilibrium data were analyzed using five equilibrium models, the Langmuir, the Freundlich, the Redlich–Peterson, the Koble–Corrigan and the Temkin isotherms. The results of non-linear regressive analysis are that the isotherms of Langmuir, Redlich–Peterson and Koble–Corrigan are better fit than the isotherms of Freundlich and Temkin at different temperatures according to the values of determined coefficients ( R 2 ) and Chi-square statistic ( χ 2 ). The maximum equilibrium capacities of chaff from Langmuir models are 20.3, 25.3 and 26.3 mg g −1 at 298, 318 and 333 K, respectively. Using the equilibrium concentration constants obtained at different temperatures, various thermodynamic parameters, such as Δ G 0 , Δ H 0 and Δ S 0 , have been calculated. The thermodynamics parameters of MB/chaff system indicate spontaneous and endothermic process. It was concluded that an increase in temperature results in a bigger MB loading per unit weight of the chaff.

Based on a new modernity theory of sociology, the followed intrinsic characteristics of transportation are discussed from the viewpoint of time-space distanciation: the limitation of space to the development of transportation, the unsymmetry between the supply and demand of transportation, the peculiarity of transportation's sustainable development among the infrastructures, the similarity in tile course of transportation development, the complexity of modem transportation. Finally, the tendency of transportation development is prospected.

Novel silica nanoparticle/CdTe quantum dot (QD) composite probes were prepared and used as reporters in fluorescent lateral flow test strips. When α-fetoprotein (AFP) was used as a model analyte, the results indicated that the fluorescent test strips were at least 10 times more sensitive than conventional gold-based test strips.