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The diamondback moth (DBM), Plutella xylostella (L.), has evolved resistance to multiple insecticides including Bacillus thuringiensis (Bt). ATP-binding cassette (ABC) transporters are a class of transmembrane protein families, involved in multiple physiological processes and pesticide resistances in insects. However, the role and regulatory mechanism of ABC transporter in mediating the response to Bt Cry1Ac toxin remain unclear. Here, we characterized a MAPK signaling pathway-enriched ABCG subfamily gene PxABCG20 from DBM, and found it was differentially expressed in the Cry1Ac-resistant and Cry1Ac-susceptible strains. RNAi knockdown of PxABCG20 increased the tolerance of DBM to Cry1Ac protoxin. To explore the regulatory mechanism of PxABCG20 expression, we predicted the potential miRNAs targeting PxABCG20 using two target prediction algorithms. Luciferase reporter assay confirmed that novel-miR-310 was able to down-regulate PxABCG20 expression in HEK293T cells. Furthermore, injection of novel-miR-310 agomir markedly inhibited PxABCG20 expression, resulting in increased tolerance to Cry1Ac protoxin in susceptible strain, while injection of novel-miR-310 antagomir markedly induced the expression of PxABCG20, leading to decreased tolerance to Cry1Ac protoxin. Our work provides theoretical basis for exploring novel targets for the DBM response to Cry1Ac toxin and expands the understanding of miRNA role in mediating the susceptibility of insect pest to Cry1Ac toxin.

To enhance the inferior energy-absorption performance of a hydraulic support during coal mine rock burst, which leads to failure and damage, a framework including a kind of corrugated laminated energy-absorbing component on the top beam of the hydraulic support is developed. First, triangular, trapezoidal and sinusoidal corrugated core energy-absorbing structures are designed, and their mathematical models are established. Second, three kinds of corrugated core components are optimized to obtain the suitable structural parameters, and based on the findings, the energy-absorption characteristic curves of the three kinds of corrugated core components are obtained through a simulation analysis. The results show that the sinusoidal corrugated core exhibits the best energy-absorption effect among the single-layer corrugated components. Among the two-layer and four-layer corrugated core components, the triangular corrugated core arrangement is the optimal arrangement. The energy absorption of the three kinds of corrugated core components is correlated with the delamination. The results of the experiment and simulation are consistent. This study provides a theoretical basis and experimental reference for the design of energy-absorbing components for an anti-impact hydraulic support.

Among all CO2 electroreduction products, methane (CH4) and ethylene (C2H4) are two typical and valuable hydrocarbon products which are formed in two different pathways: hydrogenation and dimerization reactions of the same CO intermediate. Theoretical studies show that the adsorption configurations of CO intermediate determine the reaction pathways towards CH4/C2H4. However, it is challenging to experimentally control the CO adsorption configurations at the catalyst surface, and thus the hydrocarbon selectivity is still limited. Herein, we seek to synthesize two well-defined copper nanocatalysts with controllable surface structures. The two model catalysts exhibit a high hydrocarbon selectivity toward either CH4 (83%) or C2H4 (93%) under identical reduction conditions. Scanning transmission electron microscopy and X-ray absorption spectroscopy characterizations reveal the low-coordination Cu-0 sites and local Cu-0/Cu+ sites of the two catalysts, respectively. CO-temperature programed desorption, in-situ attenuated total reflection Fourier transform infrared spectroscopy and density functional theory studies unveil that the bridge-adsorbed CO (COB) on the low-coordination Cu-0 sites is apt to be hydrogenated to CH4, whereas the bridge-adsorbed CO plus linear-adsorbed CO (COB + COL) on the local Cu-0/Cu+ sites are apt to be coupled to C2H4. Our findings pave a new way to design catalysts with controllable CO adsorption configurations for high hydrocarbon product selectivity. (C) 2020 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved.

A thorough theoretical exploration of microscopic mechanism for effect of sodium (Na) on nitric oxide (NO) heterogeneous reduction by char was performed based on density functional theory with consideration of London dispersion interaction. Calculation results show that the Na atom could migrate at edge of char and prefers to be incorporated into a five-atom ring forming a pentagon with 174.2 kJ/mol released. A strong electrostatic attraction between the Na atom and carbon atoms at the edge is found by reduced density gradient analysis. Electrons transfer from the Na atom to char, resulting in electron rearrangement on char. It is the most stable mode for adsorption of the first NO molecule when O atom in NO molecule is adjacent to the Na atom. The doping of Na could promote adsorption of the first NO molecule, but has little effect on that of the second NO molecule. The intrinsic reaction coordinate calculations and Mayer bond order analyses suggest that the Na atom affects heterogeneous reduction through “oxidized-reduced” cycle via “combination-separation” with the O atom. Desorption of N2 molecule is the rate-determining step in the whole reaction channel. The canonical variational theory was used for kinetic analyses, considering the tunneling effect along the reaction coordinate with Wigner method. It is found that the reaction is accelerated by doping Na atom. Although the addition of Na would not significantly reduce activation energy of the rate-determining step, but would increase activation sites at the edge of char.

Beneficial fungi - including difficult - to - culture arbuscular mycorrhizal fungi (AMF) and the culturable endophytic fungus Piriformospora indica - play positive roles in hosts under controlled conditions, whereas information regarding the application of these fungi in field citrus (a mycorrhizal - dependent plant) is scarce. The present study aims to analyze the effects of two AMF species (Diversispora spurca and D. versiformis) and an endophytic fungus (P. indica) on the fruit quality and soil properties of Newhall navel oranges (Citrus sinensis Osbeck cv. Newhall) grafted on trifoliate oranges in the field. The results showed the improvement of root fungal colonization following fungal inoculation. The fungal inoculations increased the soil's acid, neutral, alkaline, and total phosphatase activity, as well as soil Bray-P content; increased the distribution of water-stable aggregates, mainly in the size range of 2–4 mm; and stimulated the production of easily extractable, difficultly extractable, and total glomalin-related soil proteins in a fungal-species-dependent manner, which was positively correlated with soil aggregate stability. Fungal inoculations, to some extent, improved external fruit quality, depending on the fungal species. Among the three fungi, only D. versiformis significantly increased the fruits' soluble solid content, but all three together promoted fruit glucose, fructose, and sucrose content. The two AMF species dramatically increased fruit phosphorus (P) content, while P. indica distinctly reduced it. D. versiformis also significantly elevated fruit potassium (K), magnesium (Mg), and manganese (Mn) content, D. spurca improved fruit copper (Cu), zinc (Zn), K, and Mg content, and P. indica increased fruit iron (Fe) and Zn content, compared with non-inoculated controls. Our results indicate that the field inoculation of citrus with AMF and P. indica partially improved fruit quality and soil properties, providing a pathway for P. indica to partially replace AMF in field citrus applications.

Although the lithium metal battery has been considered to be one of the most promising candidates to facilitate high-density energy storage, the practical applications of lithium metal anodes are significantly hindered by its high reactivity. Electrolytes based on 1,3-dioxolane (DOL) have been demonstrated to be one of the most effective electrolytes that can suppress side reactions, but the underlying mechanism is still far from clear. In this work, we carried out multi-scale simulations that combine density functional theory (DFT) and reactive force field (ReaxFF) to investigate the initial reactions of 1.0 M LiPF6 salt in DOL with Li metal anode. Our simulation results reveal that PF6− anions can either fully decompose via reduction reaction when they directly in contact with Li anode or convert to PF5 when they stay in bulk. While the decomposition products (F− and Px−) contribute to the formation of the inorganic part of the solid electrolyte interphase (SEI), the latter PF5 can serve as an initiator of the polymerization of DOL. Such polymerization of the electrolyte provides an unexpected protective effect that resembles the polymer electrolyte but is formed in situ. The most kinetically favorable polymerization pathway is then distinguished from hybrid functional DFT calculations, which confirms that PF 5 plays an important role in activating the DOL ring for further polymerization. The insights revealed from this work should be of help to expedite the rational design of electrolytes that provide protective SEI to stabilize Li anode.

Biclustering algorithm is to cluster in the horizontal and vertical directions simultaneously in matrix. This algorithm identifies a set of sub-matrix by adopting a greedy iterative strategy, which employs the mean squared residue to measure the element consistency of a sub-matrix. Biclustering algorithm is widely applied in large and complex data. However, different versions of biclustering algorithm always have the problem that with the increasing of data size, more irrelevant rows or columns are involved in clustering which results in the poor performance of clustering. Therefore, this paper proposes a new algorithm, which combines fuzzy member matrix and comprehensive evaluation in fuzzy mathematics with multi-objective optimization algorithm to improve the performance of biclustering algorithm. In order to validate the effectiveness of the new algorithm, the performance the new algorithm and other three mainstream algorithms are compared on three gene/protein expression datasets. The results show the new algorithm has better element consistency, and sub-matrix capacity than other algorithms.

To analyze the clinical outcomes of nasopharyngeal carcinoma (NPC) patients with post-radiation nasopharyngeal necrosis (PRNN) and construct a new risk classification system for predicting survival of PRNN.A total of 276 patients with PRNN were consecutively enrolled. Complete magnetic resonance (MR) images of the nasopharynx and neck were available for all patients and were used to assess nasopharyngeal necrosis status. After 2010, patients with PRNN were initially treated by radical endoscopic necrectomy followed by reconstruction with nasal flap (ENNF).The 1-year and 2-year overall survival (OS) was 65.0% and 51.6%, respectively. Three variables affected survival: osteoradionecrosis, re-irradiation, and internal carotid artery (ICA) exposure, and only two variables were found to be independent prognostic factors: re-irradiation (hazard ratio [HR] 1.75, P=0.001) and internal carotid artery (ICA) exposure (hazard ratio [HR] 1.80, P=0.001). These two variables were combined to create a new risk classification system for PRNN. 131 (47.5%), 110 (39.9%), and 35 (12.7%) patients were classified into low-, intermediate- and high-risk group, with the 2-year OS rates of 64.8%, 45.1%, and 22.5%, respectively (P0.001). ENNF was associated with a better OS in these three group patients compared with conservative management with statistical or marginal statistical significance (2-year OS low-risk group, 90.9% vs 61.1%, p=0.081; intermediate-risk group: 100% vs 37.8%, P=0.001; and high-risk group, 57.1% vs 20.8%, p=0.066).The new risk classification system provides accurate estimates of prognosis. ENNF surgery may lead to better survival outcome than conservative management in PRNN patients.

Polydimethylsiloxane (PDMS) elastomer is one of most investigated and pioneering 3D printing materials. However, the powder-based 3D printing remains a big challenge due to the thermoset intrinsic character of PDMS. Here we realized the powder-based selective laser sintering (SLS) 3D printing of PDMS elastomer based on one kind of novel self-designed PDMS covalent adaptable networks (CANs) containing hindered pyrazole urea dynamic bonds. The dynamic chemical mechanism of the hindered pyrazole urea bonds is confirmed by small molecule models experiments, density functional theory calculation, and also stress relaxation analysis. The electron-donating large steric hindrance substituent in the pyrazole ring was found to effectively promote the dynamic character of pyrazole urea bond. The PDMS CANs show excellent self-healing and reprocessing properties. Furthermore, kilo-scale PDMS powders were prepared by cryogenic grinding and the powder morphology was optimized for SLS 3D printing. A PDMS insole with complex structure designed based on the personalized foot pressure distribution data was printed, and the foot orthotic and self-healing functions for the insole were demonstrated.

Hydrogen evolution reaction (HER), a promising strategy for converting electricity to value-added H2 fuel, is a key half reaction of the overall water splitting. However, HER is suffering from the sluggish kinetics in alkaline. We here demonstrate a highly efficient catalyst for alkaline HER via surface and interface engineering of RhOOH nanosheets (NSs). The surface structure of RhOOH NSs can be precisely tuned by altering the cyclic voltammogram cycles (CVs) in the activation process, leading to the formation of strongly synergized RhOOH/Rh interface for boosted HER activity in alkaline. The optimized catalyst exhibits a promising alkaline HER performance with overpotential of 18 mV at current density of 10 mA∙cm−2 and Tafel slope of 19.3 mV∙dec−1 in 1 M KOH, which surpasses the commercial Pt/C, Rh NSs/C and RhOOH NSs/C. Detailed experiments and theoretical calculations reveal that the synergy between RhOOH and Rh significantly promotes the H2O adsorption/dissociation to form Had and the Had desorption to produce H2.

Purpose To explore the value of combined modalities, including anatomical and functional magnetic resonance imaging (MRI), endoscopy and computed tomography (CT), for the assessment of tumor responses to definitive chemoradiotherapy (dCRT) in esophageal squamous cell carcinoma (ESCC). Methods Sixty-seven patients with locally advanced ESCC were enrolled. Tumor response (TR) was assessed two months after the completion of dCRT. Evaluation criteria according to combined modalities, including MRI, endoscopy and CT, were established and compared with traditional criteria based on CT and endoscopy. Progression-free survival (PFS)⩾12months was used as the reference standard, and the accuracy of the two criteria in response assessment was analyzed. Results Thirty-seven (55.2%) and 10 (14.9%) patients were considered to exhibit CR, as assessed by combined modalities and the traditional criteria, respectively. Using PFS⩾12months as a surrogate for CR, the sensitivity and specificity of the combined modalities were 82.4% and 88.9%, respectively, compared with 20.6% and 92.6% for the traditional criteria. TR assessed by combined modalities (CR vs. non-CR) was prognostic of PFS in univariate and multivariate analyses (Log-rank, P Conclusions Tumor responses assessed by the combined modalities of MR, endoscopy and CT seemed highly predictive of prognosis after dCRT in ESCC patients.

Thermal cis→trans isomerization for a series of BF2-coordinated azo compounds of the para-substitution with electron donating groups have been systematically investigated. The density-functional theory calculations exhibited good performance to provide better understanding of the effects of para-substitution with electron donating groups. It is found that the different electron donation groups can significantly affect the absorption spectra, the energy levels of molecular orbitals, the transition properties for the trans isomers, the rate constants and the half-lives for the thermal cis→trans isomerization. Our calculated half-lives for the thermal cis→trans isomerization are in qualitative agreement with the experimental values. Specifically, we have evaluated the thermal rate constants at 294 K. The relationship between the thermal isomerization and the para-substituted electron-donating group reveals that the inversion mechanism is preferred for the substituent species while the rotation mechanism is more favorable for non-para-substituent molecule.

The structures and properties of a family of different π-conjugation tetra pyrrole Zn complexes are reported. The tetra pyrrole moiety can be divided as porphyrin, one tripyrrin and one pyrrole, two dipyrrines, one dipyrrin and two pyrroles, and four pyrroles. The Zn complexes possess different geometries and tunable spectral bands depending on the mode of the different metal-coordination. For Zn porphyrin, the frontier molecular orbitals (FMOs) are the major contribution to the intense B-like band and weak Q-like band absorptions, and this is in agreement with the Gouterman’s four-orbital model. But because of the breakdown of the π-conjugation from complex 1 to 5, the FMOs are no longer separated from the other MOs in energy, the orbital with metal distribution is approaching to lowest unoccupied molecular orbital (LUMO), the absorption band is no longer intense at B-like bond and weak at Q-like bond as Gouterman's four-orbital model mentioned. The calculated fluorescence spectra in toluene solution show that fluorescence can be observed in the visible region of complexes 1–4 because of the bright higher electronic excited states.

HCN is an important precursor of nitric oxide (NO) during pulverized coal combustion. A thorough theoretical exploration with density functional theory and wave functional theory was performed to elucidate the effect mechanism of Fe on HCN heterogeneous formation from nitrogen-containing char. Based on X-ray photoelectron spectroscopy analysis, an aromatic cluster model consisting of pyridinic nitrogen was chosen for simulation. Electronic structure analysis showed that abundant π electrons were sufficiently delocalized above and below the basal model plane. Maxima of electrostatic potential existed at every hollow site at the center of a hexagon on van der Waals surface. Calculation results indicated that chemisorptions of iron atoms on seven different hollow sites were exothermic spontaneous reactions with the formation of interstitial iron carbides and iron nitrides. It was verified by reduced density gradient analysis that the Fe atom and nitrogen containing char were mainly combined by electrostatic attraction. Heterogeneous desorption of HCN from nitrogen containing char was endothermic, whether iron was in presence or not. The rate-determining step was the ring-opening process of the nitrogen heterocyclic ring when iron not bonding to the nitrogen atom, while it was the breakage of Fe-N bond when iron combined with the nitrogen atom. Thermodynamic and kinetics analyses found that the participation of Fe had inhibiting effect on heterogeneous formation of HCN except the direct binding of iron to nitrogen.

Photothermal therapy (PTT) normally requires to maintain the temperature of tumor lesions above 50 °C, which potentially induces local inflammation and tumor metastasis. To avoid these side effects, it is vital to achieve effective antitumor efficacy at relatively low temperature (42–45 °C) during the PTT treatment. Herein, we design a polydopamine (PDA)-coated nucleic acid nanogel as a therapeutic complex for siRNA-mediated low-temperature PTT. First, siRNAs that target the heat-shock-protein 70 (Hsp70) serve as crosslinkers to guide the DNA-grafted polycaprolactone (DNA-g-PCL) assemble into nanosized hydrogel particles through nucleic acid hybridization. Thereafter, the obtained siRNA-embedded nanogels are further coated with a thin layer of polydopamine, which not only protects the nanogels against enzymatic degradation but also endows the nanogels with excellent photothermal conversion capacity under near infrared (NIR) light irradiation. After surface PEGylation, this triple shield siRNA delivery complex shows the capability of effective ablating the tumor under relatively mild condition.

The effect mechanism of Ca on nitric oxide (NO) heterogeneous reduction by char was investigated using density functional theory calculations with correction of London dispersion interaction. Non-catalytic heterogeneous reduction of NO by char was also studied for comparison. Electron spin density and dual descriptor of the simplified char model with zigzag configuration were analyzed to predict adsorption sites of the NO molecule and Ca atom. It was found with the method of reduced density gradient that the calcium atom and carbon atoms at the edge of char were mainly combined by electrostatic attraction. The activation energy of each elementary reaction in the two reaction pathways indicated that Ca showed catalytic activity in the formation of N-N bond and the desorption of N2 molecule. The fitted reaction activation energy was 76.34 kJ/mol for NO heterogeneous reduction at the edge of pristine char; whereas it was 51.78 kJ/mol for that at the edge of Ca-decorated char. Calculation results also showed that the addition of Ca could shorten the reaction path of NO heterogeneous reduction. The promotion of Ca to NO heterogeneous reduction was attributed to combination of the two aspects above.

The local electric field formed between dye sensitizers and semiconductor interface is one of key factors to determine the overall performance of dye-sensitized solar cells (DSSCs). Herein, a strategy has been proposed to explore the influence of the local electric field on the functionality of DSSCs of YD2-O-C8 dye via calculating the relevant properties in various electric field strengths. The YD2-O-C8 dye has been systemically studied with density functional theory (DFT) and time-dependent DFT (TD-DFT) for its electronic structure and optical properties in tetrahydrofuran (THF) solution. The absorption spectra are gradually narrowing and blue-shifting while increasing the electric field strength. Two key parameters of the light harvesting efficiency (LHE) and the TiO 2 conduction band shift (Δ E cb ) have been examined for the YD2-O-C8 sensitized TiO 2 system. It is found that it is of great importance to reduce the charge accumulation on the TiO 2 film, which lowers the electric field strength and shows the best performance of DSSCs. This study is expected to deepen our understanding of the function of local electric field and the operational principles of the DSSCs for further optimization.

The social and spatial patterns of ageing population in urban China illuminate the influence of the socioeconomic transformation associated with the dual economic system. Guangzhou, one of China's megacities, is used as a case study in this paper. Data from the 2010 National Census were used to examine the spatial differentiation and the related factors of ageing communities in Guangzhou. Using social area analysis, the study identified six categories of ageing communities: traditional inner-city communities, traditional danwei residential communities, commercial housing ageing communities, danwei compound ageing communities, immigrant ageing communities, and rural ageing communities. The paper analyses the reasons and processes leading to the clustering of the elderly population in each category of areas associated with distinctive spatial patterns of ageing differentiation. These patterns suggest that the socio-spatial differentiation of ageing communities is a joint outcome of urban development, housing policies, personal status and family relationships. The dynamics of both ageing in place and ageing with migration had a dual impact on the spatial, social and ecological patterns of ageing communities. The spatial differentiation of ageing communities in the study area should be taken into account when formulating urban planning and public policies. In addition, a dynamic public facility and service allocation system is also necessary to meet the needs associated with evolving socio-spatial urban restructuring.

Based on titanium dioxide model and LJBs sensitizers (triphenylamine as the donor, 3,4-ethylene dioxy thiophene plus various functionalized phenylenes as the π-spacer, and cyanoacrylic acid as the anchoring group) with different connection types on TiO2 substrate, the reasonable dye-TiO2 connection has been located. The results show that the dissociative adsorption of LJBs is more thermodynamically favorable than the neutral molecule bound configurations. LJBs adsorb onto TiO2 via interaction between 3d orbital of surface Ti atom and 2p orbital of N/O atoms in the acceptors. This result is confirmed in both neutral and dissociation forms of LJBs molecules. According to our calculations, adding a meta-fluorine substituent to the phenyl group of cyanoacrylic acid (LJB-Fm) may damage the planarity and conjugation. Consequently, the light harvesting efficiency decreased, and that is particularly unfavorable for the DSSCs application. The Ortho F-substituted dye (LJB-Fo), however, exhibited enhanced light absorption and more efficient intra-molecular charge transport. The bigger Jsc, Voc values of LJB-Fo system predicts its superior DSSC performance. Additionally, LJBs anchored on TiO2 surface via group –COO (LJB-H and LJB-Fo) lead to an indirect mechanism for electron injection. While LJB-Fm preferred to direct electron injection mechanism due to the strong orbital-coupling between sensitizer and the TiO2 substrate.

Linear Temporal Logic (LTL) Model Checking is a very important and popular technique for the automatic verification of safety-critical hardware and software systems, aiming at ensuring their quality. However, it is well known that LTL model checking suffers from the state explosion problem, often leading to insurmountable scalability problems when applying it to real-world systems. While there has been work on distributed algorithms for explicit on-the-fly LTL model checking, these are not sufficiently scalable and capable of tolerating faults during computation, significantly limiting their usefulness in huge cluster environments. Moreover, implementing these algorithms is generally viewed as a very challenging, error-prone task. In this paper, we instead rely on Pregel, a simple yet powerful model for distributed computation on large graphs. Pregel has from the start been designed for efficient, scalable and fault tolerant operation on clusters of thousands of computers, including large cloud setups. To harness Pregel's power, we propose a new vertex centric distributed algorithm for explicit LTL model checking of concurrent systems. Experimental results illustrate feasibility and scalability of the proposed algorithm. Compared with other distributed algorithms, our algorithm is more scalable, reliable and efficient. We propose a new vertex centric distributed algorithm for LTL model checking.Algorithm is designed for BSP model and can be implemented in Pregel.The whole model checking procedure can be highly paralleled by BFS.Our algorithm is more scalable, reliable, efficient and expressive.Our proposed algorithm opens the door to reliable model checking implementations.

The hierarchical porous Fe3O4/PPy-Pd-II catalyst has been synthesized using Fe3O4 microspheres both as chemical template and oxidant source under sonication. The catalyst characterized by TEM, XRD, FT-IR, XPS and vibrating sample magnetometry (VSM). The catalyst showed high reactivity for the carbonylative cross-coupling reaction of aryl iodides with arylboronic acids. This newly developed catalyst could be easily recovered and revealed high efficiency and high stability under the reaction conditions and during recycling stages. (C) 2014 Elsevier B.V. All rights reserved.

Graphene nanosheets (GS) are non-covalently functionalized with novel N,N-bis-(n-butylimidazolium bromide salt)-3,4,9,10-perylene tetracarboxylic acid diimide (PTCDI-ILs) via the pi-pi stacking, and then employed as the support of Pd nanoparticles. The negatively charged Pd precursors are adsorbed on positively charged imidazolium ring moiety of PTCDI-ILs wrapping GS surface via electrostatic self-assembly and then in situ reduced by NaBH4. X-ray diffraction and transmission electron microscope images reveal that Pd nanoparticles with an average size of 2.7 nm are uniformly dispersed on GS surface. The Pd/PTCDI-ILs/GS exhibits unexpectedly high activity toward alcohol oxidation reaction, which can be attributed to the large electrochemical surface area of Pd nanoparticles. It also shows enhanced electrochemical stability due to the structural integrity of PTCDI-ILs/GS. This provides a facile approach to synthesize GS-based nanoelectrocatalysts. (C) 2013 Elsevier Ltd. All rights reserved.

A new functionalized SBA-15 catalyst immobilized CuI was successfully prepared, and the catalytic activity was tested in the oxidative homocoupling of terminal alkynes at the absence of base, and good to excellent yields was obtained to get 1,3-diynes without any side product formation in the solution of DMSO. Moreover, the system also allowed the synthesis of unsymmetric 1,3-diynes by cross-coupling of two different terminal alkynes. Finally, the catalyst could be reused for several times without a significant loss of activity.

An acid–base bifunctionalized magnetic nanoparticles catalyst Fe3O4@SiO2-A/B was successfully synthesized by immobilization of both organic base and acid groups together over silica-coated magnetite nanoparticles. The catalyst has been characterized by transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectra (XPS) measurements. The bifunctionalized magnetic nanoparticles act as an easily recovered, highly efficient catalyst for the Henry reaction of 4-nitrobenzaldehyde with nitromethane at mild reaction conditions, even exceeding any monofunctionalized catalyst or physical mixture of two monofunctionalized nanoparticles in the catalytic behavior. In addition, a probable mechanism has been proposed to explain the cooperative interactions from the presence of the immobilized base and acid groups in close proximity. Importantly, the catalyst can be simply recoverable from the reaction mixture by magnetic decantation and recycled without significant degradation in reactivity.

To evaluate patterns of skull base invasion and its possible impact on tumor (T)-staging in nasopharyngeal carcinoma (NPC) using magnetic resonance imaging (MRI).838 consecutive newly diagnosed by biopsy proven and untreated patients with NPC underwent MRI. The skull-base invasion of NPC was classified according to their incidence from proximal sites to more distant sites surrounding the nasopharynx as: high (≥35%), medium (≥5-35%), and low (5%) groups. A retrospective analysis of data consisting of a 5-year follow-up was carried out. The skull base invasion was related to their tumor (T) staging and prognosis at the 5-year follow-up after treatment with definitive radiation therapy. In addition, a survival health-related quality of life (QOL), overall survival (OS), local relapse-free survival (LRFS) and distant metastasis-free survival (DMFS) were also assessed among the three groups.The total incidence of skull-base invasion was 65.51% (549/838). The differences in T-stage distribution, and the total survival health-related QOL, among the three groups were statistically significant (χ(2)=160.45, p0.005; χ(2)=38.43, p0.005, respectively). The differences between any two of the three groups were also significant, except when the medium grade was compared to the low grade. Significant differences were observed with regard to 5-year OS (83.2%, 74.7%, 59.2%, p=0.000) and DMFS (95.0%, 88.0%, 88.0%, p=0.016); no significant difference was observed in LRFS (95.3%, 95.6%, 91.23%, p=0.450).The results indicate that medium and low group displayed similar findings of skull base invasion, and survival status. We, therefore, propose that patients in these two groups be grouped under T4 in the TNM classification that might have a bearing in implementing optimum treatment.

Purpose To investigate the correlation between the alterations of single-voxel 1 H MRS and the histopathological characteristics of radiation brain injury following radiation. Materials and methods Twenty-seven rabbits were randomized into nine groups to receive radiation with a single dose of 25Gy. The observation time points included a pre-radiation and 1, 2, 3, 4, 5, 6, 7, and 8wk following radiation. Each treatment group underwent conventional MRI and single-voxel 1 H MRS, N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were observed over the region of interest, and the presence or absence of lactate (Lac) and lipid (Lip) was detected. Histological specimens of each group were obtained after image acquisition. Results The values of Cho were significantly increased in the first 3wk, and decreased over the following 5wk after radiation. Levels of NAA showed a trend toward a decrease 5wk after radiation. The levels of Cr were not changed between before and after radiation. The Cho/NAA metabolic ratio was significantly increased in weeks 6, 7, and 8 following irradiation, compared to pre-radiation values. Vascular and glial injury appeared on 2wk after RT in the histology samples, until 4wk after RT, necrosis of the oligodendrocytes, neuronal degeneration and demyelination could be observed. Conclusions MRS is sensitive to detect metabolic changes following radiation, and can be used in the early diagnosis of radiation brain injury.

We present here the de novo assembly and annotation of the transcriptome of Plutella xylostella (diamondback moth (DBM)), a widespread destructive pest of cruciferous plants, using short reads generated by Illumina sequencing from different developmental stages and insecticide-resistant strains. A total of 171,262 non-redundant sequences, denoted as unigenes, were obtained. They represented approximately 100-fold of all DBM mRNA and EST sequences in GenBank thus far. We identified 38,255 unigenes highly similar to the known functional protein-coding genes, most of which were annotated using gene ontology (GO) and orthologous groups of proteins (COG). Global profiling of differentially expressed unigenes revealed enriched GOs and biological pathways that were related to specific developmental stages and insecticide resistance. We also evaluated the resistance-related single nucleotide polymorphism (SNP) using this high-throughput genotyping method. The newly developed transcriptome will facilitate researches on the DBM developmental biology and insecticide resistance evolution, and ultimately provide better pest management systems.

Objective To summarize the CT and MRI features in a series of fifteen cases of Kimura's disease. Materials and methods The clinical data, CT and MRI findings of 15 patients with histologically proved Kimura's disease were retrospectively reviewed. All imaging data were consensually evaluated by two radiologists to determine the lesion location, number, morphology, margin, signal intensity or CT density, lesion texture, contrast enhancement pattern and involvement of adjacent structures. Results There were 14 male and 1 female, with peripheral blood eosinophilia in all 14 patients. 13 patients were presented with a painless mass. 13 patients had lesions located in the head and neck related to the major salivary glands. 1 patient had lesion in groin. Subcutaneous fat diffuse atrophy around the tumor site was found in 11 patients. 9 patients had solitary mass and 6 patients had multiple masses. Most masses were ill-defined, but no specific density or signal patterns were found. Most patients exhibited enlarged or obviously enhanced abnormal lymph nodes but without necrosis. Conclusion The characteristic distribution, morphology with enlarged draining lymphadenopathy, combined with the clinical features and laboratory examination enables a confident preoperative diagnosis of Kimura's disease.

Since security threats to WSNs are increasingly being diversified and deliberate, prevention-based techniques alone can no longer provide WSNs with adequate security. However, detection-based techniques might be effective in collaboration with prevention-based techniques for securing WSNs. As a significant branch of detection-based techniques, the research of anomaly detection in wired networks and wireless ad hoc networks is already quite mature, but such solutions can be rarely applied to WSNs without any change, because WSNs are characterized by constrained resources, such as limited energy, weak computation capability, poor memory, short communication range, etc. The development of anomaly detection techniques suitable for WSNs is therefore regarded as an essential research area, which will enable WSNs to be much more secure and reliable. In this survey paper, a few of the key design principles relating to the development of anomaly detection techniques in WSNs are discussed in particular. Then, the state-of-the-art techniques of anomaly detection in WSNs are systematically introduced, according to WSNs' architectures (Hierarchical/Flat) and detection technique categories (statistical techniques, rule based, data mining, computational intelligence, game theory, graph based, and hybrid, etc.). The analyses and comparisons of the approaches that belong to a similar technique category are represented technically, followed by a brief discussion towards the potential research areas in the near future and conclusion.

Na–montmorillonite was modified via an ion-exchange reaction with octadecyl dihydroxy ethyl methylammonium bromide (ODEM). The modified material (Na–Mt) was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM). The basal spacing of the modified Na–Mt was 2.47 nm and the IR spectra of modified Na–Mt showed CH2 vibrations. The adsorption of phenol by modified Na–Mt from aqueous solution was indicative of a pseudo-second-order model which was used to calculate the corresponding rate constants (2.07 g/mg min−1 at 308 K), and the Langmuir isotherms fitted the adsorption best, giving the highest adsorption capacity (384.61 mg/g at 308 K). The calculated thermodynamic parameters suggested that the adsorption of phenol onto modified Na–Mt was physisorptive, spontaneous and exothermic in nature.

This paper studies on strata and surface movement laws with long wall fully mechanized gangue backfilling technology by similar material simulation and numerical simulation method. The results indicate that 1) the overlying strata under the situation of mining with long wall fully mechanized gangue backfilling mainly shows a slow bending and subsidence, characterized by bending, fracturing, and bed separating, while the overlying strata develops fractured zone and bending zone only; and 2) if the compression rate of backfill is about 30%, the surface subsidence coefficient is around 0.22. In addition, this paper points out that improving the filling rate of gangue backfilling in goaf and the initial density of filling body are the main technological way to enhance the controlling effect of strata movement. Based on this point of view, four technical measures are proposed at the end.

To elucidate the mechanism of alkaline hydrolysis and aminolysis of cephalosporin (Cep) and its thioxo analogue, thioxocephalosporin (Thi), density functional theory and continuum dielectric method were used to map out the solution-phase free-energy profiles. The hydrolysis reactivity of Cep was similar to that of Thi, but Cep was much slower in aminolysis than Thi due to different expulsion between the incoming hydroxide anion and amine. Furthermore, the rate-limiting step for Cep, in both hydrolysis and aminolysis, was the approaching of the negatively charged ion toward the anionic reactant to form a tetrahedral intermediate, and the breakdown of four-membered β-lactam for Thi. The predicted rate-limiting step and relative energy barrier for the hydrolysis and aminolysis of Cep and Thi were in agreement with the experimental results. By establishing model systems, the different reactivity between Cep and Thi was rationalized through amide resonance.

Mycorrhizal fungi may play an important role in protecting plants against arsenic (As) contamination. However, little is known about the direct and indirect involvement of arbuscular mycorrhizal fungi (AMF) in detoxification mechanisms. A compartmented pot cultivation system ('cross-pots') is used here to investigate the roles of AMF Glomus mosseae in plant phosphorus (P) and As acquisition by Medicago sativa, and P-As interactions. The results indicate that fungal colonization dramatically increased plant dry weight by a factor of around 6, and also substantially increased both plant P and As contents (i.e. total uptake). Irrespective of P and As addition levels, AM plants had shoot and root P concentrations 2 fold higher, but As concentrations significantly lower, than corresponding uninoculated controls. The decreased shoot As concentrations were largely due to "dilution effects" that resulted from stimulated growth of AM plants and reduced As partitioning to shoots. The study provides further evidence for the protective effects of AMF on host plants against As contamination, and have uncovered key aspects of underlying mechanisms. The possible application of AMF in remediation practices is discussed.