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Writing assessments are an indispensable part of most language competency tests. In our research, we used cross-classified models to study rater effects in the real essay rating process of a large-scale, high-stakes educational examination administered in China in 2011. Generally, four cross-classified models are suggested for investigation of rater effects: (1) the existence of sequential effects, (2) the direction of the sequential effects, and (3) differences in raters by their individual characteristics. We applied these models to the data to account for possible cluster effects caused by the application of multiple rating strategies. The results of our research showed that raters demonstrated sequential effects during the rating process. In contrast to many other studies on rater effects, our study found that raters exhibited assimilation effects. The more experienced, lenient, and qualified raters were less susceptible to assimilation effects. In addition, our research demonstrated the feasibility and appropriateness of using cross-classified models in assessing rater effects for such data structures. This paper also discusses the implications for educators and practitioners who are interested in reducing sequential effects in the rating process, and suggests directions for future research.

We report the development and validation of a scale to measure online shopping addiction. Inspired by previous theories and research on behavioral addiction, the Griffiths's widely accepted six-factor component model was referred to and an 18-item scale was constructed, with each component measured by three items. The results of exploratory factor analysis, based on Sample 1 (999 college students) and confirmatory factor analysis, based on Sample 2 (854 college students) showed the Griffiths's substantive six-factor structure underlay the online shopping addiction scale. Cronbach's alpha suggested that the resulting scale was highly reliable. Concurrent validity, based on Sample 3 (328 college students), was also satisfactory as indicated by correlations between the scale and measures of similar constructs. Finally, self-perceived online shopping addiction can be predicted to a relatively high degree. The present 18-item scale is a solid theory-based instrument to empirically measure online shopping addiction and can be used for understanding the phenomena among young adults.

The magnetic adsorbent, Fe3O4@[Ni(HL)2]2H2[P2Mo5O23]·2H2O (Fe3O4@1), is synthesized by employing the nanoparticles Fe3O4 and polyoxometalate hybrid 1. Zero-field-cooled (ZFC) and field-cooled (FC) curves show that the blocking temperature of Fe3O4@1 was at 120 K. Studies of Fe3O4@1 removing cationic and anionic dyes from water have been explored. The characterization of Fe3O4@1, effects of critical factors such as dosage, the concentration of methylene blue (MB), pH, adsorption kinetics, isotherm, the removal selectivity of substrate and the reusability of Fe3O4@1 were assessed. The magnetic adsorbent displayed an outstanding removal activity for the cationic dye at a broad range of pH. The adsorption kinetics and isotherm models revealed that the adsorption process of Fe3O4@1 was mainly governed via chemisorption. The maximum capacity of Fe3O4@1 adsorbing substance was 41.91 mg g−1. Furthermore, Fe3O4@1 showed its high stability by remaining for seven runs of the adsorption-desorption process with an effective MB removal rate, and could also be developed as a valuable adsorbent for dyes elimination from aqueous system.

Plates (37 mm thick) of 6005A-T6 aluminum alloy were butt joined by a single-sided and double-sided friction stir welding (FSW). The 3D residual stresses in the joints were determined using neutron diffraction. The microstructures were characterized by a transmission electron microscope (TEM) and electron backscatter diffraction (EBSD). In the single-sided FSW specimen, there were acceptable mechanical properties with a tensile strength of 74.4% of base metal (BM) and low residual stresses with peak magnitudes of approximately 37.5% yield strength of BM were achieved. The hardness is related to the grain size of the nugget zone (NZ), and in this study, precipitations were dissolved due to the high heat input. In the double-sided FSW specimen, there were good mechanical properties with a tensile strength of 80.8% of BM, but high residual stresses with peak magnitudes of approximately 70% yield strength of BM were obtained. The heat input by the second pass provided an aging environment for the first-pass weld zone where the dissolved phases were precipitated and residual stresses were relaxed.

In this work, two magnetic adsorbents Fe3O4@1 and Fe3O4@2 were prepared by combining Fe3O4 nanoparticles and polyoxometalate hybrids [Ni(HL)2]2H2[P2Mo5O23]·4H2O (1), [H2L]5H[P2Mo5O23]·12H2O (2) (HL = 2-acetylpyridine-thiosemicarbazone). The temperature-dependent zero-field-cooled (ZFC) and field-cooled (FC) measurements indicated the blocking temperature at 160 K and 180 K, respectively. The Brunauer–Emmett–Teller (BET) surface area of Fe3O4@1 and Fe3O4@2 is 8.106 m2/g and 1.787 m2/g, respectively. Cationic dye methylene blue (MB) and anionic dye methyl orange (MO) were investigated for selective dye adsorption on Fe3O4@1 and Fe3O4@2. The two adsorbents were beneficial for selective adsorption of cationic dyes. The adsorption efficiency of MB was 94.8% for Fe3O4@1, 97.67% for Fe3O4@2. Furthermore, the two adsorbents almost maintained the same adsorption efficiency after seven runs. The maximum MB adsorption capacity of Fe3O4@1 and Fe3O4@2 is 72.07 and 73.25 mg/g, respectively. The fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) spectra of the adsorbents collected after adsorption of MB are very similar to the initial as-synthesized Fe3O4@polyoxometalates indicating the high stability of the two adsorbents. The adsorption kinetics indicated that the MB removal followed the pseudo-second-order model. These results showed that the two adsorbents had a potential application in treating wastewater.

Purpose. To determine the efficacy and safety of preoperative intravitreal conbercept (IVC) injection before vitrectomy for proliferative diabetic retinopathy (PDR). Methods. 107 eyes of 88 patients that underwent pars plana vitrectomy (PPV) for active PDR were enrolled. All patients were assigned randomly to either preoperative IVC group or control group. Follow-up examinations were performed for three months after surgery. The primary bioactivity measures were severity of intraoperative bleeding, incidence of early and late recurrent VH, vitreous clear-up time, and best-corrected visual acuity (BCVA) levels. The secondary safety measures included intraocular pressure, endophthalmitis, rubeosis, tractional retinal detachment, and systemic adverse events. Results. The incidence and severity of intraoperative bleeding were significantly lower in IVC group than in the control group. The average vitreous clear-up time of early recurrent VH was significantly shorter in IVC group compared with that in control group. There was no significant difference in vitreous clear-up time of late recurrent VH between the two groups. Patients that received pretreatment of conbercept had much better BCVA at 3 days, 1 week, and 1 month after surgery than control group. Moreover, both patients with improved BCVA were greater in IVC group than in control group at each follow-up. Conclusions. Conbercept pretreatment could be an effective adjunct to vitrectomy in accelerating postoperative vitreous clear-up and acquiring stable visual acuity restoration for PDR.

The multi-layered cell envelope structure of Gram-negative bacteria represents significant physical and chemical barriers for short-tailed phages to inject phage DNA into the host cytoplasm. Here we show that a DNA-injection protein of bacteriophage Sf6, gp12, forms a 465-kDa, decameric assembly in vitro. The electron microscopic structure of the gp12 assembly shows a ~150-Å, mushroom-like architecture consisting of a crown domain and a tube-like domain, which embraces a 25-Å-wide channel that could precisely accommodate dsDNA. The constricted channel suggests that gp12 mediates rapid, uni-directional injection of phage DNA into host cells by providing a molecular conduit for DNA translocation. The assembly exhibits a 10-fold symmetry, which may be a common feature among DNA-injection proteins of P22-like phages and may suggest a symmetry mismatch with respect to the 6-fold symmetric phage tail. The gp12 monomer is highly flexible in solution, supporting a mechanism for translocation of the protein through the conduit of the phage tail toward the host cell envelope, where it assembles into a DNA-injection device.

In this article, a study was presented on the adsorption activity of a new nanocomposite particle Fe3O4@1, which was synthesized by combining [Cu(HL)2]2H2[P2Mo5O23]·10H2O (1) (HL = 2-acetylpyridine semicarbazone) and Fe3O4 nanoparticles. Transmission electron microscopy and X-ray powder diffraction analyses revealed that Fe3O4@1 possessed high crystallinity with an average particle size of 19.1 nm. The adsorption activity of the as-prepared Fe3O4@1 was investigated by photometrically monitoring the removal of methylene blue, rhodamine B, safranine T, gentian violet, fuchsin basic, and methyl orange from aqueous solutions. Significantly, we could easily separate Fe3O4@1 from the reaction media by applying an external magnet. Furthermore, the recycling performance was observed using methylene blue, revealing the recyclability and high stability of Fe3O4@1. It was shown that Fe3O4@1 is a promising candidate material for adsorbing cationic dyes in aqueous media.

DNA detection with high sensitivity and specificity has tremendous potential as molecular diagnostic agents. Graphene and graphene-based nanomaterials, such as graphene nanopore, graphene nanoribbon, graphene oxide, and reduced graphene oxide, graphene-nanoparticle composites, were demonstrated to have unique properties, which have attracted increasing interest towards the application of DNA detection with improved performance. This article comprehensively reviews the most recent trends in DNA detection based on graphene and graphene-related nanomaterials. Based on the current understanding, this review attempts to identify the future directions in which the field is likely to thrive, and stimulate more significant research in this subject.

In recent years, tapered optical fibers (TOFs) have attracted increasing interest and developed into a range of devices used in many practical applications ranging from optical communication, sensing to optical manipulation and high-Q resonators. Compared with conventional optical fibers, TOFs possess a range of unique features, such as large evanescent field, strong optical confinement, mechanical flexibility and compactness. In this review, we critically summarize the multimode interference in TOFs and some of its applications with a focus on our research project undertaken at the Optoelectronics Research Centre of the University of Southampton in the United Kingdom.

Arthrobacter pascens ZZ21 is a plant-beneficial, fluoranthene-degrading bacterial strain found in the rhizosphere. The production of the phytohormone indole-3-aectic acid (IAA) by ZZ21 is thought to contribute to its ability to promote plant growth and remediate fluoranthene-contaminated soil. Using genome-wide analysis combined with metabolomic and high-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses, we characterized the potential IAA biosynthesis pathways in A. pascens ZZ21. IAA production increased 4.5-fold in the presence of 200 mg·L−1 tryptophan in the culture medium. The transcript levels of prr and aldH, genes which were predicted to encode aldehyde dehydrogenases, were significantly upregulated in response to exogenous tryptophan. Additionally, metabolomic analysis identified the intermediates indole-3-acetamide (IAM), indole-3-pyruvic acid (IPyA), and the enzymatic reduction product of the latter, indole-3-lactic acid (ILA), among the metabolites of ZZ21, and subsequently also IAM, ILA, and indole-3-ethanol (TOL), which is the enzymatic reduction product of indole-3-acetaldehyde, by HPLC-MS. These results suggest that the tryptophan-dependent IAM and IPyA pathways function in ZZ21.

In this paper, the physical phenomena of gallium (Ga+) ion impacting monolayer graphene in the nanosculpting process are investigated experimentally, and the mechanisms are explained by using Monte Carlo (MC) and molecular dynamics (MD) simulations. Firstly, the MC method is employed to clarify the phenomena happened to the monolayer graphene target under Ga+ ion irradiation. It is found that substrate has strong influence on the damage mode of graphene. The mean sputtering yield of graphene under 30 keV Ga+ ion irradiation is 1.77 and the least ion dose to completely remove carbon atoms in graphene is 21.6 ion/nm2. Afterwards, the focused ion beam over 21.6 ion/nm2 is used for the irradiation on a monolayer graphene supported by SiO2 experimentally, resulting in the nanostructures, i.e., nanodot and nanowire array on the graphene. The performances of the nanostructures are characterized by atomic force microscopy and Raman spectrum. A plasma plume shielding model is put forward to explain the nanosculpting results of graphene under different irradiation parameters. In addition, two damage mechanisms are found existing in the fabrication process of the nanostructures by using empirical MD simulations. The results can help us open the possibilities for better control of nanocarbon devices.

Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs) in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50) and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1) active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2) these active bacteria use more resources in the nematodes' gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3) inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes.

Quantitative real time reverse transcription polymerase chain reaction has been applied in a vast range of studies of gene expression analysis. However, real-time PCR data must be normalized with one or more reference genes. In this study, eleven putative consistently expressed genes (ACT, TUA, TUB, CYP, DNAj, ELFA, F-box27, RPL12, GAPDH, UBC and UBQ) in nine Siberian Apricot Germplasms (including much variability) were evaluated for their potential as references for the normalization of gene expression by NormFinder and geNorm programs. From our studies, ACT, UBC, CYP, UBQ and RPL12 as suitable for normalization were identified by geNorm, while UBC and CYP as the best pair by NormFinder. Moreover, UBC was selected as the most stably expressed gene by both algorithms in different Siberian Apricot seed samples. We also detected that a set of three genes (ACT, CYP and UBC) by geNorm as control for normalization could lead to accurate results. Furthermore, the expression levels of oleosin gene were analyzed to validate the suitability of the selected reference genes. These obtained experimental results could make an important contribution to normalize real-time PCR data for gene expression analysis in Siberian Apricot Germplasm.

Sentence comprehension involves timely computing different types of relations between its verbs and noun arguments, such as morphosyntactic, semantic, and thematic relations. Here, we used EEG technique to investigate the potential differences in thematic role computing and lexical-semantic relatedness processing during on-line sentence comprehension, and the interaction between these two types of processes. Mandarin Chinese sentences were used as materials. The basic structure of those sentences is "Noun+Verb+'le'+a two-character word", with the Noun being the initial argument. The verb disambiguates the initial argument as an agent or a patient. Meanwhile, the initial argument and the verb are highly or lowly semantically related. The ERPs at the verbs revealed that: relative to the agent condition, the patient condition evoked a larger N400 only when the argument and verb were lowly semantically related; however, relative to the high-relatedness condition, the low-relatedness condition elicited a larger N400 regardless of the thematic relation; although both thematic role variation and semantic relatedness variation elicited N400 effects, the N400 effect elicited by the former was broadly distributed and reached maximum over the frontal electrodes, and the N400 effect elicited by the latter had a posterior distribution. In addition, the brain oscillations results showed that, although thematic role variation (patient vs. agent) induced power decreases around the beta frequency band (15-30 Hz), semantic relatedness variation (low-relatedness vs. high-relatedness) induced power increases in the theta frequency band (4-7 Hz). These results suggested that, in the sentence context, thematic role computing is modulated by the semantic relatedness between the verb and its argument; semantic relatedness processing, however, is in some degree independent from the thematic relations. Moreover, our results indicated that, during on-line sentence comprehension, thematic role computing and semantic relatedness processing are mediated by distinct neural systems.

Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease in pigs caused by PRRS virus (PRRSV). Although PRRSV infection-induced cell apoptosis has been established, the related viral protein is still unknown. Here, we reported that PRRSV nonstructural protein 4 (nsp4) was a critical apoptosis inducer. Nsp4 could activate caspase-3, -8, and -9. Using truncated constructs without different domains in nsp4, we demonstrated that the full-length of nsp4 structure was required for its apoptosis-inducing activity. Furthermore, using site-directed mutagenesis to inactivate the 3C-like serine protease activity of nsp4, we showed that nsp4-induced apoptosis was dependent on its serine protease activity. The ability of nsp4 to induce apoptosis was significantly impaired by His39, Asp64, and Ser118 mutations, suggesting that His39, Asp64, and Ser118 were essential for nsp4 to trigger apoptosis. In conclusion, our present work showed that PRRSV nsp4 could induce apoptosis in host cells and might be partially responsible for the apoptosis induced by PRRSV infection. PRRSV 3C-like protease-mediated apoptosis represents the first report in the genus Arterivirus, family Arteriviridae.

In the title compound, [Zn(C12H6N2O2)3](ClO4)2·CH3CN, the ZnII atom is coordinated by six N atoms from three chelating 1,10-phenanthroline-5,6-dione ligands in a distorted octahedral environment. In the crystal, intermolecular C—H...O hydrogen bonds and O...π and N...π interactions [O...centroid distances = 2.907 (5) and 2.843 (7) Å; N...centroid distance = 2.861 (10) Å] link the complex cations, perchlorate anions and acetonitrile solvent molecules into a three-dimensional network.