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Internet addiction (IA) is associated with adverse consequences, especially for younger people. Evidence indicates that IA is associated with depression, but no studies have yet investigated potential common vulnerability between them.IA (measured by the Young's 20-item Internet Addiction Test Scale) and depressive symptoms (measured by the Patient Health Questionnaire-9 Scale) among 12 043 undergraduates were surveyed at baseline and at a respective 12 month follow-up for each participant. Application of a cross-lagged panel model approach (CLPM) revealed an association between IA and depression after adjusting for demographic variables.Rates of baseline IA and depression were 5.47% (95% CI: 5.07%, 5.88%) and 3.85% (95% CI: 3.51%, 4.20%), respectively; increasing to 9.47% (95% CI: 8.94%, 9.99%) and 5.58% (95% CI: 5.17%,5.99%), respectively, at follow-up. Rates of new-incidences of IA and depression over 12 months were 7.43% (95% CI: 6.95%, 7.91%) and 4.47% (95% CI: 4.09%, 4.84%), respectively. Models in the present analysis revealed that baseline depression had a significant net-predictive effect on follow-up IA, and baseline IA had a significant net-predictive effect on follow-up depression.The follow-up survey response rate was moderate (54.69%) in this analysis of university students. Moreover, the IAT-20 scale did not allow differentiate between specific forms of Internet activity.Common vulnerability and bidirectional cross-causal effects may both contribute to the association between IA and depression, with common vulnerability likely playing a more significant role than cross-causal effects.

The effect of thickness deviation on the optical properties of graphene-based optical microstructure was studied by using the transfer matrix method. Machining errors led to inconsistencies in the thicknesses of different parts and resulted in an offset of absorption peak, thus significantly reducing the average light absorption. The 3-nm deviation decreased the light absorption of graphene-optical microstructure by approximately 3.5 times. However, if the machining error is included in the design, then a relatively small Q value will help reduce the effect of machining error and the light absorption can be enhanced by about 32%.

A new rock-like resin has been developed after extensive formula research. This resin is completely transparent and low temperature brittle. Its tension-compression ratio can reach 1/6.6 in the −10 to −15 °C temperature range. It can simulate many kinds of engineering rocks. Specimens are made with a single internal crack. The progressive failure processes of specimens under uniaxial and biaxial compressions are investigated. The uniaxial failure process of specimens is divided into four stages. Some forms of secondary cracks, like anti-wing cracks in biaxial test, have never been reported in previous studies. 3-D numerical simulation is carried out using FLAC3D. A new elastic-brittle constitutive model is developed in the simulation. Superfine element division is also required. The uniaxial and biaxial numerical results of the new method possess an excellent consistency with experiment results in this paper.

In this work, a novel series of tofacitinib analogs were designed and synthesized based on the scaffold hybridization strategy and then evaluated for their antiproliferative activity toward three gastric cancer cell lines, leading to the identification of compound C18 which exhibited potent inhibitory activity against MGC-803 cell lines with an IC50 value of 2.68 μM. Compound C18 could effectively inhibit the colony formation, suppress the cell migration and induce apoptosis of MGC-803 cells through activating the p38 and JNK signaling pathways, while C18 showed no obvious effect on the cell cycle distribution in MGC-803 cells. In addition, C18 could initiate mitochondrial dysfunction of MGC-803 cells. Besides, in vivo antitumor studies indicated that C18 could inhibit gastric cancer tumor growth in vivo without obvious global toxicity.

Previous research showed that a lectin from the mushroom Laetiporus sulphureus, designed LSL, bound to Sepharose and could be eluted by lactose. In this study, by taking advantage of the strong affinity of LSL-tag for Sepharose, we developed a single-step purification method for LSL-tagged fusion proteins. We utilized unmodified Sepharose-4B as a specific adsorbent and 0.2 M lactose solution as an elution buffer. Fusion proteins of LSL-tag and porcine circovirus capsid protein, designated LSL-Cap was recovered with purity of 90 ± 4%, and yield of 87 ± 3% from crude extract of recombinant Escherichia coli. To enable the remove of LSL-tag, tobacco etch virus (TEV) protease recognition sequence was placed downstream of LSL-tag in the expression vector, and LSL-tagged TEV protease, designated LSL-TEV, was also expressed in E. coli., and was recovered with purity of 82 ± 5%, and yield of 85 ± 2% from crude extract of recombinant E. coli. After digestion of LSL-tagged recombinant proteins with LSL-TEV, the LSL tag and LSL-TEV can be easily removed by passing the digested products through the Sepharose column. It is of worthy noting that the Sepharose can be reused after washing with PBS. The LSL affinity purification method enables rapid and inexpensive purification of LSL-tagged fusion proteins and scale-up production of native proteins.

With a bipolar pulse power, wear-resistant ceramic coatings with high micro-hardness were in-situ fabricated on 2A50 aluminum alloy using micro-arc oxidation method in silicate electrolyte. The effect of cathodic voltage on microstructure, phase structure, micro-hardness and wear properties was investigated by changing cathodic voltage from 0 to −200 V. The phase structure, microstructure, micro-hardness and wear resistance were determined by XRD, SEM, HVS-1000 Vicker's micro-hardness tester and tribology tester. The results show that the phase of the obtained coatings is mainly composed of γ-Al2O3. The coating consists of the inner dense layer and the outer loose layer. As the cathodic voltage increases, the quantity and size of the micro-pores in the coatings first decrease and then increase. Micro-arc oxidation can greatly strengthen 2A50 aluminum alloy, the micro-hardness increases from 75 HV0.5 to 1321 HV0.5 after a micro-arc oxidation under a cathodic voltage of −100 V. The friction coefficient of the ceramic coatings are in the range of 0.35–0.55, and the coating obtained under −100 V exhibits the best wear resistance. The wear mechanism is deduced to be the combination of abrasive and adhesive wear.

Alkaline phosphatase (ALP) is an important biomarker for diagnosis, and the abnormal level of serum ALP is closely related to a variety of diseases. In present work, a ratiometric fluorescence probe based on hybrid nanoparticles CDs@YVO4: Dy3+ nanoparticle is introduced for alkaline phosphatase (ALP) activity determination. The CDs@YVO4: Dy3+ probe is constructed by the carbon dots (CDs) and YVO4: Dy3+ through a simple mixing method, in which the blue emission of CDs at 405 nm acts as the calibrated signal, the green emission of YVO4: Dy3+ at 574 nm decreased with the increasing targets ALP, and used as the output signal. In addition, the Cu2+ and pyrophosphate (PPi) were also employed in this strategy to utilize the excellent fluorescnece quenching efficiency of Cu2+ to the Dy3+ ions emission of CDs@YVO4: Dy3+, as well as the strong affinity of PPi for Cu2+. In the presence of analyts ALP, ALP catalyzes the hydrolysis of PPi, causing the release of Cu2+, resulting in the Dy3+ ions emission quenched, while the CDs emission at 405 nm retained unchanged, based on this, we designed the off-on-off ratiometric fluorescence platform for ALP sensing. The experiment result shows that the ratio of F574/F405 is linear to the concentration of ALP in arange of 0.05∼3000 U/L with a detection limit of 0.04 U/L, which is comparable or better than those reported fluorescence probe, especially the calibrated signal introduction of CDs can eliminate the background interference, improve the accuracy of proposed probe greatly. Furthermore, the discrimination of ALP enzyme inhibitor with the IC50 of 26 μM, and ALP concentration in real human serum sample has also demonstrated the applicability of CDs@YVO4: Dy3+ fluorescence sensor well.

Background Mutations in SLC6A1 have been associated mainly with myoclonic atonic epilepsy (MAE) and intellectual disability. We identified a novel missense mutation in a patient with Lennox-Gastaut syndrome (LGS) characterized by severe seizures and developmental delay. Methods Exome Sequencing was performed in an epilepsy patient cohort. The impact of the mutation was evaluated by 3H γ-aminobutyric acid (GABA) uptake, structural modeling, live cell microscopy, cell surface biotinylation and a high-throughput assay flow cytometry in both neurons and non neuronal cells. Results We discovered a heterozygous missense mutation (c700G to A [pG234S) in the SLC6A1 encoding GABA transporter 1 (GAT-1). Structural modeling suggests the mutation destabilizes the global protein conformation. With transient expression of enhanced yellow fluorescence protein (YFP) tagged rat GAT-1 cDNAs, we demonstrated that the mutant GAT-1(G234S) transporter had reduced total protein expression in both rat cortical neurons and HEK 293 T cells. With a high-throughput flow cytometry assay and live cell surface biotinylation, we demonstrated that the mutant GAT-1(G234S) had reduced cell surface expression. 3H radioactive labeling GABA uptake assay in HeLa cells indicated a reduced function of the mutant GAT-1(G234S). Conclusions This mutation caused instability of the mutant transporter protein, which resulted in reduced cell surface and total protein levels. The mutation also caused reduced GABA uptake in addition to reduced protein expression, leading to reduced GABA clearance, and altered GABAergic signaling in the brain. The impaired trafficking and reduced GABA uptake function may explain the epilepsy phenotype in the patient.

A simple and green method for the determination of trace bisphenol A (BPA) was established by coupling supported ionic liquid solid-phase extraction to β -cyclodextrin modified ionic liquids carbon paste electrode-based electrochemical detection (SILs-SPE-ED). The synthesized imidazolium ionic liquids modified styrene type macroporous resin was used as adsorbent for SPE of BPA. The experimental parameters that affected the extraction efficiency were investigated and optimized. Dynamic adsorption test showed that the maximum adsorption capacity of BPA on the SILs-SPE cartridge was 10.1 mg g −1 , and the enrichment factor was 40. The calibration curve showed a good linearity between the anodic current and the BPA concentration in the range of 1.0 × 10 −8 −1.0 × 10 −6 M. The detection limit was 4.16 nM (equal to 0.95 μg L −1 ). The SILs-SPE-ED method, with the advantages including high sensitivity and good practicability, was applied to the analysis of real water and plastic samples, and the results agreed well with HPLC method.

Mining in western China, particularly in the southern regions of the Yangtze River such as Chongqing, has created surface fissures in soils that can cause severe geological disasters, for example, paddies can lose water and become dry land. The objectives of this study are to detect anomalies in paddy fields by using geophysical exploration technologies such as ground penetrating radar (GPR) and electrical resistivity tomography (ERT), and to verify the detection of leaking zones by using saturated hydraulic conductivity (K) with a simplified falling head infiltrometric technique (SFH). We discover that GPR and ERT used in conjunction produce the best results because GPR detects abnormal details in the shallow layers of the soil, and ERT detects water leakage channels in complex terrain and deep underground. However, the soil saturated hydraulic conductivity of our study area could be affected by the depth and soil density above the fissure, which may interfere with anomaly detection.

Porous carbons (PCs) for super capacitors were prepared from coal tar pitch by a one-step microwave-assisted KOH activation with low KOH consumption. The surface area of the PC (PC 2− M ) made at a KOH/pitch mass ratio of 2 with microwave heating for 30 min reaches 1786 m 2 /g. The electrochemical performance of the PC electrode for super capacitors was evaluated in different electrolytes including KOH, K 2 SO 4 , Na 2 SO 4 , Li 2 SO 4 in water, and tetraethylammonia tetrafluoroborate in propylene carbonate. The super capacitors have a high specific capacitance of 267 F/g in 6 M KOH aqueous electrolyte at 0.1 A/g and a high energy density of 12.0 W/kg at 1318 W/kg in a 0.5 M K 2 SO 4 neutral electrolyte. The one-step microwave-assisted KOH activation is a simple, efficient and low energy-consumption approach for the preparation of high performance PCs for super capacitors. [New Carbon Materials 2014, 29(6): 493–502]

The light pulse delay in Bragg-spaced graphene layers (BSGs) combined with a magnetic field is investigated theoretically. BSGs can slow down the group velocity of light more effectively than traditional Bragg-spaced quantum wells due to the large binding energy and strong dipole oscillator strength of the magnetic-exciton of graphene. The group velocity can be tuned by varying the pulse frequency, the Bragg frequency, and the magnetic field. Especially, by tuning the occupation number of the Landau level the group velocity in BSGs shows strong tunable circular dichroism. Our findings could have applications in photonic integrated circuits and quantum computation.

Poly (aspartic acid-co-leucine) (PL) synthesized with aspartic acid and leucine was conjugated to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) by ethylenediamine. Then the compound obtained was chelated with gadolinium (III) to form PL-A 2 -DOTA-Gd. The structure of PL-A 2 -DOTA-Gd was characterized by nuclear magnetic resonance and gel chromatography and its performance was evaluated by cytotoxicity test, heamolysis test, in vitro relaxivity determination and animal in vivo magnetic resonance characterization. PL-A 2 -DOTA-Gd exhibited much lower cytotoxicity than Gd-DOTA. The T1-relaxivity of PL-A 2 -DOTA-Gd (15.3 mM −1 s −1 ) was 2.6 times than that of Gd-DOTA (5.8 mM −1 s −1 ) in D 2 O. The results of magnetic resonance imaging (MRI) experiments showed a significant enhancement in the rat liver imaging after the intravenous administration of PL-A 2 -DOTA-Gd. In addition, the imaging time persisted by using PL-A 2 -DOTA-Gd than that of Gd-DOTA and the imaging effect of liver tissue was enhanced by an average of 65.1% ± 5.2% and 21.3% ± 4.9% for PL-A 2 -DOTA-Gd and Gd-DOTA, respectively.

Differential interferometric synthetic aperture radar (DInSAR) technology is a new method to monitor the dynamic surface subsidence. It can monitor the large scope of dynamic deformation process of surface subsidence basin and better reflect the surface subsidence form in different stages. But under the influence of factors such as noise and other factors, the tilt and horizontal deformation curves regularity calculated by DInSAR data are poorer and the actual deviation is larger. The tilt and horizontal deformations are the important indices for the safety of surface objects protection. Numerical simulation method was used to study the dynamic deformation of LW32 of West Cliff colliery in Australia based on the DInSAR monitoring data. The result indicates that the subsidence curves of two methods fit well and the correlation coefficient is more than 95%. The other deformations calculated by numerical simulation results are close to the theory form. Therefore, considering the influence, the surface and its subsidiary structures and buildings due to mining, the numerical simulation method based on the DInSAR data can reveal the distribution rules of the surface dynamic deformation values and supply the shortcomings of DInSAR technology. The research shows that the method has good applicability and can provide reference for similar situation.

a b s t r a c t Objectives: To evaluate the effect of luting cement and thermomechanical loading on the retention of glass fibre posts in root canals. Methods: One hundred and forty-four single-rooted human premolars were endodontically treated and restored with RelyX Fibre Posts. The teeth were divided into four groups according to the cements used (Fuji I, Fuji CEM, RelyX Unicem and RelyX ARC). Each group was further divided into two subgroups according to the method of ageing (immediately tested and after thermomechanical loading). Bond strength was evaluated using a pull-out test. Microleakage was examined quantitatively with dye penetration. The dentine‐cementpost bonding interface was assessed using scanning electron microscopy. Data were analysed with two-way ANOVA (pull-out test) and Kruskal‐Wallis analysis (microleakage). Results: The pull-out bond strength and microleakage were significantly affected by the type of cement and ageing. Although RelyX ARC showed the highest bond strength before thermomechanical loading ( p < 0.05), the sealing ability of this cement was worse than those exhibited in Fuji CEM and RelyX Unicem ( p < 0.05). After thermomechanical loading, pull-out strengths of Fuji I and Fuji CEM were significantly increased, whereas that of RelyX ARC group significantly decreased ( p < 0.05). The sealing ability of Fuji CEM was significantly better than the two resin cement groups ( p < 0.05) after ageing. Conclusion: Fuji CEM demonstrates increased pull-out strength after thermomechanical loading and favourable sealing ability compared with the other cements. Clinical significance: Resin-modified glass ionomer cements have the potential benefit of achieving long-term retention when used for luting glass fibre post to root canal dentine. So it may be recommended for the cementation of glass fibre post in clinics.

A catalytic diastereo- and enantiocontrolled preparation of cis -β-fluorocyclopropane carboxylates through the Rh-catalyzed cyclopropanation of alkenyl fluorides with diazoarylacetates has been realized. Rh 2 ( S -DOSP) 4 and benzyl diazoarylacetates were found to be beneficial to the cyclopropanation with high diastereoselectivity. Thirteen cis -β-fluorocyclopropane carboxylates were prepared in hexane at 0 °C with good to excellent yields. The enantiomeric excess was up to 97%, and the diastereomer ratio was up to 95:5.

Plenty of round holes or special holes distributed in measuring device and mould component with higher positional requirement, in general, are formed in WEDM technology. In the process of WEDM operation, whole holes with high requirement should be finished in one time, which can avoid of positional error and enhance the positional precision effectively. Investigate into the geometrical tolerance and present in an improved process. This process can both suitable for WEDM-HS and WEDM-LS.

Hydrogen production from the aqueous phase derived from fast pyrolysis of biomass was carried out by catalytic steam reforming in a fluidized bed reactor. The effects of reaction conditions such as reaction temperature, steam-to-carbon ratio (S/C) and weight hourly space velocity of the aqueous phase (WHSV) on the results of hydrogen yield, potential hydrogen yield and carbon selectivity of product gases were investigated. The effect of reaction temperature on the carbon deposition on catalyst was also studied. The hydrogen yield of 64.6%, potential hydrogen yield of 77.6% and the carbon selectivity for product gases of 84.3% can be obtained at the optimized conditions of reaction temperature 800 °C, S/C 10 and WHSV 1.0 h−1.

Magnetic resonance imaging (MRI) is one of the most useful diagnostic techniques in clinical medicine and more than 30% of all MRI examinations are accompanied by administration of a contrast agent which has become a class of pharmaceuticals. The principles, characterization and classification and recent developments of MRI contrast agents are presented in this review. The primary focus of such research is to study the MRI contrast agents with organ-selectivity, high relaxivity and safety.

Based on an opening complex for a hydropower station in China, an equation considering four basic factors was fitted for prediction of displacement at the key point on the high sidewalls of the powerhouse, on the basis of a large number of numerical simulations. The basic factors include rock deformation modulus, overburden depth of caverns, height of the powerhouse and the lateral pressure coefficient of the initial stress. Quasi-three-dimensional stability analyses were carried out by using FLAC3D. With an equation, the elasto-plastic displacement and elastic displacement at a sidewall key point can be calculated quickly. The equation was applied to predict the displacements at key points on the sidewalls for caverns of nine projects. The computation results were compared with numerical modeling or back-analysis results. In addition, in order to consider the effects of cavern spacing, a new equation was proposed. Finally, three possible criteria for stability evaluation of the rock masses were considered. It is suggested that the rock stability is assessed by the ratio θ c between the elasto-plastic displacement and the elastic displacement, which is commonly applicable. The stability of the surrounding rock for the above-mentioned nine underground projects was evaluated by the method. Long prestressed cables were considered to be needed to reinforce the sidewalls in order to ensure the stability of the caverns for some of the projects. For the actual design and construction of the five relevant projects, long prestressed cables were employed for reinforcement of high sidewalls. This showed that the evaluation criterion was valid.

The biochemical effects of gadolinium chloride were studied using high-resolution H-1 nuclear magnetic resonance (NMR) spectroscopy to investigate the biochemical composition of tissue (liver and kidney) aqueous extracts obtained from control and gadolinium chloride (GdCl3) (10 and 50 mg/kg body weight, intraperitoneal injection. i.p.) treated rats. Tissue samples were collected at 48, 96 and 168 h p.d. after exposure to GdCl3, and extracted using methanol/chloroform solvent system. H-1 NMR spectra of tissue extracts were analyzed by pattern recognition using principal components analysis. The liver damages caused by GdCl3 were characterized by increased succinate and decreased glycogen level and elevated lactate, alanine and betaine concentration in liver. Furthermore, the increase of creatine and lactate, and decrease of glutamate, alanine, phosphocholine, glycophosphocholine (GPC), betaine, myo-inositol and trimethylamine N-oxide (TMAO) levels in kidney illustrated kidney disturbance induced by GdCl3.

Online sampling experiments were carried out to investigate the development of immiscible polymer blend morphology along a single screw extruder using specially designed sampling devices. The morphology of molten blend samples collected at different locations was observed by scanning electron microscopy (SEM) and evaluated both qualitatively and quantitatively. Two polypropylene/polyamide-6 blends with different viscosity ratios, one about 0.1 and the other about 1.0, were selected to investigate the influence of the viscosity ratio on the morphology development. Experimentally observed results showed that, for the blend with a smaller viscosity ratio, major morphological changes occurred during the initial softening stage of blending. For the blend with a larger viscosity ratio, the extended striations are transformed to a droplet morphology gradually along the screw. It was demonstrated that it is possible to detect the morphology development along the extruder screw nearly in real time with the sampling device assembled in a single screw extruder. Information about the dynamics of morphology development in the extruder can be obtained.

The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, respectively due to using remote sensing image with medium or low spatial resolution. Meanwhile, we present a new method of fc estimation based on a random set of fc maximum and minimum values from digital camera (DC) survey data and a dimidiate pixel model. The results show that this is a convenient, efficient and accurate method for fc monitoring, with the maximum error −0.172 and correlation coefficient of 0.974 between DC survey data and the estimated value of the remote sensing model. The remaining DC survey data can be used as verification data for the precision of the fc estimation. In general, the estimation of fc based on DC survey data and a remote sensing model is a brand-new development trend and deserves further extensive utilization.

The effects of copolymer composition, drug structure and initial drug feed on drug loading of polymeric micelles based on amphiphilic polyphosphazenes were investigated. It was found that the drug loading capacity of micelles based on this type of amphiphilic copolymers was mainly determined by copolymer composition and the chemical structure of drug. In addition to the compatibility between drug and micellar core, hydrogen bonding interaction between drug and hydrophilic corona may significantly influence drug loading as well. In vitro drug release in 0.1 M PBS (pH 7.4) suggested that indomethacin (IND) in the micelles was released through Fickian diffusion, and no significant difference in release rate was observed for micelles based on copolymers with various EtTrp content. Compared with in vitro IND release profile, in vivo pharmacokinetic study after subcutaneous administration provides a more sustained release behavior. Additionally, in comparison with free drug solution at the same dose, IND concentration in rat plasma showed a prolonged retention when the drug was delivered through polymeric micelles. In vivo pharmacodynamic study based on both carrageenan-induced acute and complete Freund's adjuvant-induced adjuvant arthritis model indicated that sustained therapeutic efficacy could be achieved through intraarticular injection of IND-loaded micelles. Most importantly, local delivery of IND can avoid the severe gastrointestinal stimulation, which was frequently associated with oral administration.