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ObjectiveThis study explored the relationship between college students’ physical activity motivation and exercise behavior and constructed a chain mediation model through the mediating roles of exercise climate and exercise self-efficacy.MethodsBy random sampling, 1,032 college students were investigated using the Exercise Motivation Scale, Physical Exercise Rating Scale, Exercise Climate Scale, and Exercise Self-Efficacy Scale.Results(1) There was a huge positive correlation between exercise motivation and exercise behavior (r = 0.240, p β = 0.068, t = 0.040, p β = 0.373, t = 0.061, p β = 0.174, t = 0.039, p β = 0.302, t = 0.051, p β = 0.190, t = 0.048, p Conclusion(1) Exercise climate, exercise self-efficacy, and exercise behavior can all be significantly predicted by exercise motivation, suggesting that exercise motivation may help to enhance these variables. (2) In addition to having a direct impact on exercise behavior, exercise motivation can also have an indirect impact through the separate mediating effects of exercise climate and exercise self-efficacy as well as the chain mediating effect of exercise climate and exercise self-efficacy, which is crucial for encouraging college students to engage in physical activity.

The ZrO2-Mg-HA powders were fabricated by the chemical precipitation and pressureless sintering technology. The dental filling materials were prepared in combination with ZrO2-Mg-HA powders and polymethacrylate. The phase composition, fracture morphology and mechanical performance of the ZrO2-Mg/HA composites were investigated in details. The results showed that the introduction of moderate content of the ZrO2 was benefit to improve the compressive strength of the material. The investigated ZrO2-Mg/HA composites could meet the requirements for the dental filling materials.

Aphids harbor primary endosymbionts, Buchnera aphidicola, in specialized cells within their body cavities. Aphids and Buchnera have strict mutualistic relationships in nutrition exchange. This ancient association has received much attention from researchers who are interested in endosymbiotic evolution. Previous studies have found parallel phylogenetic relationships between non-galling aphids and Buchnera at lower taxonomic levels (genus, species). To understand whether relatively isolated habitats such as galls have effect on the parallel relationships between aphids and Buchnera, the present paper investigated the phylogenetic relationships of gall aphids from Pemphigus and allied genera, which induce pseudo-galls or galls on Populus spp. (poplar) and Buchnera. The molecular phylogenies inferred from three aphid genes (COI, COII and EF-1α) and two Buchnera genes (gnd, 16S rRNA gene) indicated significant congruence between aphids and Buchnera at generic as well as interspecific levels. Interestingly, both aphid and Buchnera phylogenies supported three main clades corresponding to the galling locations of aphids, namely leaf, the joint of leaf blade and petiole, and branch of the host plant. The results suggest phylogenetic conservatism of gall characters, which indicates gall characters are more strongly affected by aphid phylogeny, rather than host plants.

In this paper, we propose a model for short-term traffic flow forecasting based on approximate dynamic programming when considering the influence of related roads. First, construct the system performance index using the error function as the objective function, adjust the action network online according to the minimum index to generate the approximate optimal control vector and the control matrix, then we can get the traffic flow data at the specific road and time to forecast. To illustrate how this method works, we use intersection traffic flow of Hongli road and Shangbu road in Futian Shenzhen as experimental data, which can be demonstrated that this method can increase the forecasting accuracy and meet the real-time forecasting requirements.

DNA barcoding uses a standard DNA sequence to facilitate species identification. Although the COI gene has been adopted as the standard, COI alone is imperfect due to several shortcomings. The primary endosymbiont of aphids, Buchnera, has higher evolutionary rates and interspecies divergence than its co-diverging aphid hosts, making it a potential tool for resolving the ambiguities in aphid taxonomy. We compared the effectiveness of employing two different DNA regions, gnd and COI, for the discrimination of over 100 species of aphids. The mean interspecific divergence of the gnd region was significantly higher than the mean intraspecific variation; there were nearly nonoverlapping distributions between the intra- and interspecific samples. In contrast, COI showed a lower interspecific divergence, which led to difficulties in identifying closely related species. Our results show that gnd can identify species in the Aphididae, which suggests that the gnd region of Buchnera is a potentially effective barcode for aphid species identification. We also recommend the 2-locus combination of gnd + COI as the aphid barcode. This will provide a universal framework for the routine use of DNA sequence data to identify specimens and contribute toward the discovery of overlooked species of aphids.

The aim of this study is to describe the remineralization effect of the nano-HA on artificial caries. The artificial dental caries are made by using sour solution, and constructing an artificial mouth' plaque culture system in vitro respectively. The scanning electron microscope (SEM) and the optical microscope are used to observe the surface of enamel specimens. The effect of remineralization is assessed with the polarized light microscopy (PLM) and the confocal laser scanning microscope (CLSM) by measuring three lesion parameters (area, total and average fluorescence). The SEM analysis shows that the cavities and defects of enamel surface are decreased and many mineral salts are sedimentated, which indicate that the nano-HA could promote remineralization for the demineralized enamel. The inhibitory effect of the spherical nano-HA on dental caries is detected in the artificial mouth test. The CLSM shows that demineralization of enamel is reduced by adding the spherical nano-HA in artificial mouth. The results show that the spherical nano HA have a remineralization effect on the artificial dental caries dramatically, and can prevent and decrease caries.

The Nano-HA powder was prepared by chemical precipitation. Magnesium powders were used to make porous ultramicron HA ceramic, and the biological properties of which were investigated by hemolysis rate and cytotoxicity tests. The experimental results shows that the hemolysis rate of the nano-HA powder and porous ultramicron HA ceramic were all less than 5% and none of them showed cytotoxicity. The results indicated that nano-HA and porous ultramicron HA ceramic were provided with good biocompatibility.

The Nano-HA powder were synthesized by chemical precipitation with Ca(H2PO4)2•H2O and Ca (OH)2 and porous HA was prepared by sintering with magnesium as pore-creator. Nano-HA powder and porous HA were characterized by wide angle X-ray diffraction, transmission electron microscopy(TEM), scanning electron microscopy (SEM), SEM in combination with energy dispersive X-ray spectroscopy (SEM-EDX), X-ray photoelectron spectroscopy. The experimental results show that HA powder synthesized by chemical precipitation is nanometer powder. Magnesium was ideal pore-creator for preparation of porous materials. The grain size of porous HA was sub-micron and MgO which existed in the grain boundary of HA as a second phase particles that played the roles of inhibiting the HA grain growth.

In this paper, honokiol nanoparticles were prepared by emulsion solvent evaporation method. The prepared honokiol nanoparticles were characterized by particle size distribution, morphology, zeta potential and crystallography. Results showed that the obtained honokiol nanoparticles at size of 33 nm might be amorphous, and could be well dispersed in water. Due to the great dispersibility in water, the obtained honokiol nanoparticles might have great potential in medical field.

In this work, a new kind of biodegradable pH-sensitive hydrogel was successfully synthesized by UV-initiated free radical polymerization. The obtained hydrogel was characterized by (1)H NMR and FTIR. Swelling behavior in different aqueous media and pH responsivity of the hydrogels were studied in detail as well. With increase in pH from 1.2 to 7.2, swelling ratio of the hydrogel increased. The morphology was observed by scanning electron microscopy, and the hydrolytic degradation behavior was also investigated in this work.

A series of low molecular weight poly(ethylene glycol)–polycaprolactone–poly(ethylene glycol) (PEG–PCL–PEG) biodegradable block copolymers were successfully synthesized using isophorone diisocyanate (IPDI) as the coupling agent, and were characterized using 1H NMR and Fourier transform infrared spectroscopy. The aqueous solutions of the PEG–PCL–PEG copolymers displayed a special thermosensitive gel–sol transition when the concentration was above the corresponding critical gel concentration. Gel–sol phase diagrams were recorded using the test-tube-inversion method; they depended on the hydrophilic/hydrophobic balance in the macromolecular structure, as well as some other factors, including the heating history, volume, and the ageing time of the copolymer aqueous solutions and dissolution temperature of the copolymers. As a result, the gel–sol transition temperature range could be altered, which might be very useful for application in injectable drug delivery systems.

The objective of this study was to investigate the inhibitory effect of the synthetic nanohydroxyapatite (HA) on dental caries. The nano-HA was synthesized by using the depositing reaction of Ca (H2PO4)2. The artificial dental caries was made by using sour solution and inoculating Streptococcus mutans (S.mutans) to the Sprague-Dawley (SD) rat’s mouth respectively. After mineralization of solution of nano-HA for 10 days, the hardness of enamel was measured. The inhibitory effect of the synthetic nano-HA on dental caries was detected by gargling way to rinse the rat tooth with the solution of nano-HA in the animal test. Transmission electron microscopy (TEM) revealed that the dried HA particles were needle-like with ф5-20nm×60nm and the sintered HA particles were spherical with less than 100nm. The remineralized test indicated that the solution of nano-HA with different shapes enhanced the hardness of artificial caries and improved the remineralization of artificial caries. The animal test showed that the dried nano-HA had the inhibitory effect on dental caries. The good absorptive effect of the nano-HA on both the saliva protein and the glucans leads to the development of interventions that could reduce or modify bacterial colonization of tooth surfaces.

The aim of this study is to describe the remineralization effect of the nano-HA toothpaste on artificial caries. The artificial dental caries is made using sour solution. The demineralized teeth specimen is put into five kinds of toothpaste solution respectively for 5 days and 10 days, which are: solution of containing needle like nano-HA, solution of containing spherical nano-HA, solution of general HA, fluorine sodium solution and physiological saline. The hardness of specimen is measured and the surface morphology is characterized by SEM. The remineralized test indicates that the nano-HA toothpaste can enhance the hardness of artificial caries and improve the remineralization of artificial caries. The SEM analysis shows that the cavities and defects of enamel surface are decreased and many mineral salts are sedimentated, which indicate that the nano-HA could promote remineralization for the demineralized enamel.

The paper deals with a kind of new method of the electro-deposition on titanium by a cathode revolves. The depositing characteristic and mechanic were studied by scanning electron microscopy and X-ray diffraction. The experimental results show that the more fine uniformity and compact calcium phosphate bioactive coatings could be produced, compared with the conventional methods. The gradient Coating, which is fine inside and porous outside, could be obtained by controlling revolving velocity. The coating would transform to the hydroxyapatite after heat-treatment. After soaking in a simulated body fluid (SBF), nano-depositions were formed on the surface of the coating, then those particles would grow up needle-like, net-like, and an apatite-like layer could be observed finally. The gradient porosity coatings produced by cathode revolving electrochemical deposition would have high anti-dissolution and bioactive.

It is an useful method for polymeric nanoparticles to load protein by electrostatic method to improve the immunogenicity of protein antigen. In this article, anionic poly(e-caprolactone)-poly(ethylene glycol)-poly(e-caprolactone) (PCEC) nanoparticles were prepared by modified emulsion solvent evaporation method, and human basic fibroblast growth factor (bFGF), as a model protein, was absorbed onto its surface due to electrostatic interaction. The prepared anionic PCEC nanoparticles, with mean diameter of 136.9 nm, had zeta potential of − 33.14 mV. The surface charge and particle size of bFGF/nanoparticles complex increased with increase of bFGF/nanoparticles mass ratio. The encapsulated bFGF could be released slowly from bFGF/nanoparticle complexes. The animal experiment indicated that the humoral immunity induced by bFGF/PCEC complex was improved greatly than that created by naked bFGF. Otherwise, the cytotoxicity of anionic PCEC nanoparticles was also evaluated by 293 cell viability. The prepared anioni...

The hydroxyapatite (HA) particle with different morphologies were prepared by adding a certain additive into Ca(H2PO4)2·H2O and controlling the bathing and sintering temperature, and the pure needle-like HA sol were obtained when the bathing temperature was 70°C. The experimental results show that the degree of crystallization of HA increase and the particles tend to accumulate with increasing of the drying and sintering temperatures. The particles of HA were spheroid, which diameters were of less than 100nm when they were sintered at the temperature of 700°C. The effect of nano-hydroxyapatite on remineralization of early enamel caries were studied too. The hardness of dismineralized enamel was increased when dismineralized enamel was remineralized by nano-hydroxyapatite. The SEM analysis shows that the interspace of enamel surface were decreased and the many mineral salts were sedimentated, which indicated that the nano-hydroxyapatie could promote remineralization for the dismineralized enamel.

The binding energy of the single and double bound polaron bound to a helium-type donor impurity in quantum wells (QWs) subject to a perpendicular electric field are calculated by a variational method. The couplings of an electron and the impurity with various phonon modes are considered. The results show that the cumulative effects of the electron–phonon coupling and the impurity–phonon coupling can contribute appreciably to the binding energy for the single bound polaron but only in some severe conditions for the double bound polaron. They also show that the binding energy is sensitive to the electric field strength. The comparison between the binding energies in the case of the impurity placed at the quantum well center and at the quantum well edge is also given.

We have calculated the ionization energy of a bound polaron confined in general step quantum wells (QWs) in the presence of an electric field, in which the coupling of an electron with confined bulk-like LO phonons, half-space LO phonons and interface phonons is considered. In particular, the interaction of the impurity with the various phonon modes is also included in QWs. Results have been obtained as a function of the barrier height, the well width, the electric field intensities and the position coordinates of the impurity in the QWs. Our numerical calculations clearly show that the interaction between the impurity and the phonon field plays an important role in screening the Coulomb interaction. It is shown that the cumulative effect of the electron–phonon coupling and the impurity–phonon coupling can contribute appreciably to the donor ionization energy. Only for a certain range of well widths can we neglect all the polaronic effects.

In this paper, polaron effects in asymmetric quantum-well structures (QW's) are investigated by using second-order perturbation theory and the modified Lee-Low-Pines (LLP) variational method. By applying the Green"s-function method, explicit analytical expressions for the electron extended-state wave functions and the density of states in a general step QW's are given. Within the framework of second-order perturbation theory, the ground-state polaron binding energy and effective mass in step and asymmetric single QW"s are studied as due to the interface optical phonons, confined bulklike LO and half-space LO phonons. The full energy spectrum is included in our calculations. The effects of the finite electronic confinement potential and the subband nonparabolicity are also considered. The relative importance of the different phonon modes is analyzed. By means of the modified LLP variational method, the binding energy of a polaron confined to asymmetric single QW's is also investigated. Our results show that in ordinary asymmetric QW"s, the asymmetry of the QW's has a significant influence on the polaron effect, which has a close relationship to the interface phonon dispersion. When the well width and one side barrier height of asymmetric single QW"s are fixed and identical with those of symmetric QW's, the polaron binding energy in asymmetric QW"s is always smaller than that in symmetric QW's. We have also found that it is necessary to include the continuum energy spectrum as intermediate states in the perturbation calculations in order to obtain the correct results; the subband nonparabolicity has a small influence on the polaron effect. Comparing our results obtained by using two different methods, good agreement is found.

Neovascular glaucoma (NVG) is a refractory disease which is difficult to manage. This study aimed at evaluating the efficacy and safety of adjunctive intravitreal bevacizumab (IVB) injection in conjunction with Ahmed glaucoma valve implantation (AGVI) in the management of NVG.This was a retrospective study of patients with NVG in whom AGVI was performed between October 2008 and May 2012. The sample was divided into two groups according to the pretreatment: with adjunctive IVB injection (the IVB group, n = 25 eyes) and without adjunctive IVB injection (the control group, n = 28 eyes). The surgical success rate, number of antiglaucoma medications used, best-corrected visual acuity (BCVA), postoperative complications, regression, and recurrence of iris neovascularization (NVI) were analyzed between the groups.The surgical outcomes of the two groups were compared. The complete success rates in the IVB and control groups were 84.0% and 64.3% at 12 months and 80.0% and 53.6% at 18 months, respectively. There was a significant difference between the two groups (P = 0.041). Mean postoperative intraocular pressures, mean number of postoperative antiglaucoma medications, and BCVA were not significant between the two groups. The NVI in 22 (88.0%) eyes had completely regressed within 2 - 8 days after IVB. However, NVI recurred in 10 eyes (40.0%) 2 - 9 months later after IVB. The IVB group had only 1 case (4.0%) of hyphema out of 25 eyes, while there were 8 (28.6%) cases of hyphema out of 28 eyes in the control group (P = 0.026).This study showed that preoperative IVB injection reduced NVI remarkably, decreased hyphema, and led to higher surgical success rates. Pre-operative IVB injection may be an effective adjunct to AGVI in the management of NVG.

Taking traffic volumes of multi -section as the research object, expanding the traffic volumes forecasting of single-spot to multi-section, proposing a new forecasting method of multi-section based on SOM network. The SOM can capture the nonlinear relationship among each section of a road network, which outperforms the traditional linear mechanism, the SOM can solve the weaknesses of slow search of traditional nonparametric regression because of effect of clustering and dimensionality- reduction as well. Finally, using the data of a road network to validate the effectiveness of proposed forecasting models, the results show that: the proposed forecasting model is effective and reliable.

In this paper, various N-trimethyl chitosan (TMC) of different molecular-weights (approximately 100 KD, approximately 200 KD, and approximately 400 KD, respectively) with the approximately degree of quartenization (DQ) of 40% were successfully synthesized. In vitro cytotoxicity of TMC solution showed the dependence of TMC concentration from 20 microg/ml to 500 microg/ml on the relative cell activity. Molecular weight of TMC did not greatly affect the cytotoxicity of TMC against HEK293 and L929 cells. TMC nanoparticles and alginate modified TMC nanoparticles were prepared by the ionic gelation method. Subsequently, we investigated the properties of TMC nanoparticles and alginate modified TMC nanoparticles intending for oral delivery of antigens. Molecular weight of TMC did not affect the loading capacity (LC) and in vitro release behavior of TMC nanoparticles. However, BSA concentration and alginate modification have strongly effect on properties of TMC nanoparticles (particle size; surface charge; loading efficiency and loading capacity). In vitro release behavior indicated that alginate modification could efficiently decrease initial burst release and extend release time in phosphate buffer (PBS, pH 7.4) and acidic solution (0.1 M HCl, pH = 1) at 37 degrees C. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) assay showed that alginate modification could effectively improve the stability of TMC nanoparticles and protect BSA from degradation or hydrolysis in acidic condition for at least 2 h.

Biodegradable polyetherester copolymer (PCL/PEG/PCL, PCEC) was synthesized by ring-opening polymerization of epsilon-caprolactone initiated by poly(ethylene glycol) (PEG). The PCEC nanoparticles were prepared by solvent diffusion method or w/o/w double emulsion method. The obtained particles' morphology was observed on scanning electron microscopy, and the particle size distribution was determined using Malvern laser particle sizer. Bovine serum albumin was used as the model water-soluble protein drug, which was successfully encapsulated in PCEC nanoparticles, the drug release behavior was studied in detail. The hydrolytic degradation behavior of the PCEC nanoparticles was also studied.

In this article, nano-magnetite particles (ferrofluid, Fe3O4) were prepared by chemical co-deposition method. A series of biodegradable triblock poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) (PCL-PEG-PCL, PCEC) copolymers were synthesized by ring-opening polymerization method from epsilon-caprolactone (epsilon-CL) initiated by poly(ethylene glycol) diol (PEG) using stannous octoate as catalyst. And the magnetic PCEC composite microspheres were prepared by solvent diffusion method. The properties of the ferrofluid, PCEC copolymer, and magnetic PCEC microspheres were studied in detail by SEM, VSM, XRD, Malvern Laser Particle Sizer, 1H-NMR, GPC, and TG/DTG. Effects of macromolecular weight and concentration of polymer, and the time for ultrasound dispersion on properties of magnetic microspheres were also investigated. The obtained magnetic PCEC microspheres might have great potential application in targeted drug delivery system or cell separation.

To develop an effective report gene system to test the effect of small interfering RNA (siRNA).HBV S gene was fused with enhanced green fluorescent protein (EGFP) gene to form HBs-GFP and the plasmid containing HBs-GFP was constructed. A vector expressing small hairpin RNA (shRNA) pAVU6 + 4sh357 was also constructed. Two plasmids were co-transfected into HepG2 cells transiently. The fluorescence of HBs-GFP was detected by fluorescence-activated cell sorting (FACS). The mRNA expression in HepG2 cells was detected by conventional RT-PCR and real-time PCR.siRNA inhibited the expression of HBs-GFP 72 hours post transfection. The fluorescence of HBs-GFP in HepG2 cells treated with pAVU6+4sh357 was reduced by 55.4% compared with that of controls. The HBs-GFP expression in HepG2 cells treated with pAVU6+4sh357 was reduced by 76.3% and 90% as measured with conventional RT-PCR and real-time PCR, respectively.This investigation demonstrated siRNA derived from shRNA expression vectors can inhibit the expression of HBs-GFP in HepG2 cells.