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Herein, we report a formal synthesis of (±)-arborisidine via the creation of Jiao’s intermediate with the critical caged structure. Starting from tryptamine, a Pictet–Spengler cyclization forged the piperidine ring, a Pd-catalyzed indole allylation and ring-closing metathesis protocol afforded a bridged aza-bicyclo[3.3.1]nonane moiety, and an intramolecular N-alkylation closed the final pyrrolidine ring. This study provides a new approach to the unique caged framework of arborisidine and relevant alkaloids.

The first total syntheses of (±)-catellatolactams A and B, two novel ansamacrolactams, are described in 5 and 8 steps, respectively. The strategy relies on an amidation reaction to couple the acylated Meldrum’s acid and an aryl amine, a regioselective C–H insertion to construct the γ-lactam moiety, and an RCM reaction to forge the macrocycles with E-olefin. This concise and scalable synthesis provided over 200 mg of the target molecules.

The first de novosynthesis of 1-hydroxyl allogibberic methyl ester, en routeto pharbinilic acid and other bioactive molecules, is accomplished in diastereoselective manner. Key reactions of the synthesis include a Pd-catalyzed Suzuki–Miyaura cross-coupling reaction, a Lewis acid-catalyzed reductive Prins cyclization reaction, and a SmI2-mediated transannular pinacol coupling reaction. The synthesis provides a new avenue to access diverse relevant bioactive molecules.

A new dynamic model of a variable-length rope, which could be used for the transient analysis of a buoy-rope-generator (BRG) wave energy system, was proposed in this paper. The model started from the basic dynamic equations of variable mass system, and took into account the physical properties such as axial force, shear and bending. According to the principle of D’Alembert-Lagrange, the equivalent integral weak formulation was firstly obtained, and through consistent linearization and isoparametric discretization, the finite element model of the variable-length rope was then derived. The Bathe scheme was employed to solve the model numerically, based on its excellent performance in solving nonlinear dynamic problems, and an automatic time step size algorithm was designed according to the number of iterations of the two substeps of Bathe scheme. The procedures of rope mesh regeneration were also put forward, where only one variable-length element was always located at the top end of the rope, and the rest were all fixed-length elements. The proposed variable-length rope model and solution schemes were verified through comparison with the results of a tank experiment. Finally, the transient dynamics of a kind of BRG system was analyzed and discussed.

•The cross sections of Fe fragmentation at 496 A MeV are investigated.•The total cross sections are consistent with theoretical predictions.•The partial cross sections are compared with other experimental results.

Highly mode group selective photonic lanterns (PLs) are desired for mode-division multiplexing transmission systems. Usually, mode selectivity is achieved by using input fibers with different core diameters or refractive indices to break degeneracy between mode groups. We demonstrate that mode group selectivity can be greatly improved by optimizing core geometry of PLs. For three-mode PLs with optimized core geometry, based on beam propagation method (BPM) simulation results, mode selectivity is improved from 23.8 dB to 43.9 dB for LP_01 mode, and mode selectivity of LP_11 mode is improved from 26.8 dB to 45.5 dB. The reason is the optimized core geometry can significantly slow down the changing of mode profile along the taper of the PL; thus adiabatic tapering requirement can be greatly alleviated. It can also be observed that the simulation results by the BPM are in good agreement with calculation of coupled-mode theory.

Influence of fiber on workability and mechanical property of ultra-high strength concrete (UHSC) were studied. Results show that, when amount of steel fiber (Equivalent diameter is 0.2mm; nominal length is 13mm; Tensile strength is 2850MPa )substituting fine aggregate is 120kg/m3, UHSC could have the best mechanical properties of 139.0MPa compressive strength, 18.0MPa flexural strength, and 10.0MPa Splitting strength; steel fiber cannot improve volume stability of UHSC.

It analyzed the performance, mechanical properties, volume stability, microstructure of hydration cementitious material of C60 self-compacting expansion concrete, which dependent on CSA to expansive ettringite source for the expansion. Results suggest that on the same curing conditions, C60 self-compacting concrete with the water-cement ratio of 0.32 admixture CSA expansive agent can effectively control the shrinkage of concrete, so that it is slightly inflated. The dosage of CSA expansive is higher, early strength of C60 self-compacting concrete is lower and its late strength declines small. It is affected little for the slump and extended degree of concrete under the superplasticizer by the expansive agent. SEM results show that CSA expansion agent can improve the pore structure of hydrated cement paste system with low water-binder ratio. The gel phase after hardening has good compactness and ettringite needlelike crystals mostly distribute at each interface layer.

It used conventional techniques and materials prepared high strength fiber reinforced concrete whose strength class is above C100 and it studied the effect of fiber content on the mechanical properties and elastic modulus. It also studied the fire resistance of fiber reinforced concrete. Results suggest that the strength of 28d concrete is above 100MPa and the highest strength is 126.4MPa. Under the same ratio conditions, the greater the volume content of steel fiber concrete flexural strength, the splitting tensile strength is higher. The steel fiber volume only affect elastic modulus of concrete little. When it heats to 300 °C, the no fiber concrete comminuted burst while the fiber concrete does not damaged at elevated temperatures up to 300 °C and continue to heat up, the crushing damage occurs at about 460 °C. Has not been damaged concrete specimens at 300 °C, the quality have emerged about 3% decline, while the compressive strength increased by 35%-52%, the highest strength reached 180.3MPa.

This paper focuses on assessing airport sustainable development ability. A new concept to evaluate the dynamic work on sustainable development is proposed, which is defined as airport sustainable development capacity as well as the status quo of Shanghai airport. The index system of airport sustainable is given, which includes Operational, Social, Environmental, Resources and energy system. The Airport Sustainable Development Comprehensive Index (ASDCI) is proposed, and investigates the parameter with Particle Swarm Optimization. Found that there was a marked improvement of Shanghai airport sustainable development by empirical analysis, especially the Environmental, Resources and energy. This mode has used in shanghai airport’s sustainable development evaluation system.

This study aims to evaluate the effect of using free fat grafts in preventing adhesion in the temporomandibular joint (TMJ) disc anchor and to observe the outcomes of free fat. Six 3-month-old mini-pigs were included in our study. The left joints were the experimental sides which had undergone releasing the anterior attachments, and free fat from the front of the ear lobe was grafted to the anterior gap. The right joints were the control group, where only the anterior attachments were released. MRIs were carried out and the maximal passive mouth openings were measured before operation, 3 months, and 6 months after operation. The joint tissues and fat specimens were excised after 3 and 6 months. The volume of fat was measured and hematoxylin and eosin (HE) staining was performed. Maximal passive mouth openings were analyzed with SPSS software package by Wilcoxon signed rank test. Maximal passive mouth openings were reduced gradually after 3 and 6 months, accompanied with the deviation of the mandible to the right side. There were significant differences between the 3 groups (P< 0.01). HE staining showed that the surface of the experimental joints was smooth while there was adhesion formation in the control joints. The volume of fat reduced respectively to 67.7 and to 42.6 after 3 and 6 months. HE staining showed new fat lobules were formed after 6 months with obvious fibrosis among the lobules. This study suggested that free fat can survive steadily 6 months after operation, with a surviving volume about 42.6 and it can also prevent adhesion formation in the TMJ disc anchor.

A kind of geological disasters such as fault and water gushing often occurs during the informational construction of deep super long tunnel, which brings momentous disaster and economic loss to construction safety, so the precise and immediate advance forecast to the situation of fault and water gushing has an important theoretical significance and practical value. The theory of geological survey method, TSP(tunnel seismic prediction) method and GPR(ground penetrating radar) method are summarized and analyzed, forecast geological prediction process for fault and water gushing in deep-buried super long tunnel is formulated with the combination of the three methods. Then a deep super long road tunnel named Da Xiang Ling is detected by using the process synthetically, which gains good prediction results. It has a certain guiding significance to similar projects.

MgAl2O4-SiC Composites were prepared by using magnesium aluminate spinel and silicon carbide powder as starting materials and the sintering mechanism was investigated at 1600°C in reduction atmosphere. Sintered samples were analyzed using XRD, SEM and EDS. The results show that Alumina-rich spinel and SiCN are formed due to the reactions between spinel and SiC. Weight loss of samples was detected due to SiO formation and volatilization. The bulk density of samples decreases and apparent porosity increases as increasing the content of SiC.

The effects of desorption temperature, air flow rate and initial soil moisture on the desorption efficiency of nitrobenzene from contaminated soil were investigated. Experiments were conducted with Yellow-brown soil contaminated by nitrobenzene in a vertical heating oven. Results showed that there was a trend that desorption efficiency of nitrobenzene increased with the increase of desorption temperature. At 250 °C, when desorption time was 30 min, desorption efficiency reached 99.8%, and the residual concentration of nitrobenzene in treated soil was only 0.3 mg/kg, which was far less than the A-level limit of Standard of Soil Quality Assessment for Exhibition Sites of China (HJ 350-2007). Besides, both too high and too low air flow rates were not in favor of nitrobenzene desorption. When the air flow rate was 2.6 m3/h, a maximal desorption efficiency reached during the early thermal desorption. In addition, initial soil moisture had a significant influence on desorption efficiency during the early thermal desorption. Nevertheless, with increasing desorption time, the effect of soil moisture diminished gradually and when desorption time reached 30 min, the effect nearly disappeared. The results obtained from this work could provide some scientific foundations for the practical soil remediation for nitrobenzene-contaminated sites by thermal desorption technology.

The development of adding optical functionality to a silicon microelectronic chip is still a great challenge in material research area. Silicon and its oxide are not luminescent for they do not possess direct electronic band transition. Here we demonstrate that room-temperature photoluminescence (PL) has been observed from silicon/silicon dioxide laser sintered body with its strongest PL intensity peak being at 387 nm (3.20 eV) and another peaked near 788 nm (1.60 eV). The effects of silicon/silicon oxide particle diameters and silicon contents on room-temperature PL of their laser co-sintering samples were studied. It was found that the PL peak intensity changes with the increasing silicon content.

A three-dimensional (3-D) cellular automaton (CA) model for simulating the dendrite morphology of cast Mg alloys has been developed. In the model a technique based on two sets of mesh is utilized to perform the simulation to reproduce the texture of Mg dendrites. The CA calculation is performed using a set of mesh that is defined by the hexagonal close-packed (HCP) crystal lattice, and other computations are carried out by using a cubic mesh. The two sets of mesh are coupled by using interpolation method. The kinetics of the solid-liquid interface is obtained directly by the difference between local equilibrium composition and local actual composition given by the solute transport equation. The model was used to simulate 3-D columnar growth of sixteen grains and 3-D equiaxed growth of a single dendrite of AZ91D alloy. Permanent mold castings of AZ91D alloy were produced and sampled for optical metallographic examinations, and the simulated results were compared with the metallographic results.

A cellular automaton (CA) model has been developed for simulating the microstructure evolution and dendrite morphology of cast magnesium alloys. The growth kinetics of dendrite tips is determined by the difference between local equilibrium composition and local actual composition obtained by solving the solute transport equation. Two sets of meshes, a hexagonal mesh and an orthogonal mesh, are used in the model to perform the simulation. The hexagonal mesh is used to perform CA calculation to reflect the texture of Mg alloy dendrites, and the orthogonal mesh is used to solve the solute transport equations. The model was applied to simulate single dendrite evolution and columnar dendrites growth of AZ91D Mg alloy, as well as multi-grain growth of Mg-10Gd-2Y-0.5Zr (wt%) Mg alloy. Permanent mold step-shaped castings of the two Mg alloys were poured and metallographic examinations were carried out for validating the present model. The simulation results agree well with metallographic results. The model can be applied to simulate the microstructure evolution and dendrite morphology of magnesium alloys.

Abstract: A two-dimensional modified cellular automaton model was developed to simulate the solidification process of magnesium alloy. The stochastic nucleation, solute redistribution, and growth anisotropy effects were taken into account in the present model. The model was used to simulate the grain size of magnesium alloy AZ91D for various cooling rates during the solidification process. To quantitatively validate the current model, metallographic experiments were carried out on specimens obtained from sand mold AZ91D step castings. The metallographic results agree well with the prediction results. The current model can be used to accurately predict the grain sizes of cast AZ91D magnesium alloy. [Copyright &y& Elsevier]

•This study firstly demonstrated the relationship between anti-thyroid antibodies (ATAbs) and NMOSD in children, and the clinical characters of NMOSD children with positive Positive ATAbs.•Gender, EDSS score, LETM, ANA, and MOG antibody differed significantly between ATAbs positive and negative NMOSD children.•MOG antibody positive is a unique marker of aggravation of neurological dysfunction in ATAbs-positive NMOSD children. Monitoring ATAbs may play an important role in predicting the prognosis of NMOSD.

In this paper, a simplified cellular automaton (CA) model was proposed for modeling the evolution of microstructure in solidification process of AZ91D magnesium alloy. Since the calculation time was significantly reduced, it might be used to predict the microstructure field of a real Mg component after solidification. The stochastic nucleation, competitive growth processes of many grains with various crystallographic orientations and the formation of eutectic structure were also taken into account. Furthermore, step castings were poured with sand and permanent molds and metallographic experiments were carried out for validating the developed models. It was shown that the simulation results are in good agreement with those obtained in the experiments.

The mRNA level for cytosolic NADP-dependent isocitrate dehydrogenase (IDH1) increases 2.3-fold, and enzyme activity of NADP-isocitrate dehydrogenase (IDH) 63%, in sterol-deprived HepG2 cells. The mRNA levels of the NADP- and NAD-dependent mitochondrial enzymes show limited or lack of regulation under the same conditions. Nucleotide sequences that are required, and sufficient, for the sterol regulation of transcription are located within a 67 bp region of an IDH1-secreted alkaline phosphatase promoter-reporter gene. The IDH1 promoter is fully activated by the expression of SREBP-1a in the cells and, to a lesser degree, by that of SREBP-2. A 5′-end truncation of 23 bp containing a CAAT and a GC-Box results in 6.5% residual activity. The promoter region involved in the activation by the sterol regulatory element binding proteins (SREBPs) is located at nucleotides −44 to −25. Mutagenesis analysis identified within this region the IDH1-SRE sequence element GTGGGCTGAG, which binds the SREBPs. Similar to the promoter activation, electrophoretic mobility shifts of probes containing the IDH1-SRE element exhibit preferential binding to SREBP-1a, as compared with SREBP-2.

Directional water transport that occurs in natural insects and plants is important to both organisms and advanced science and technology. Despite the many studies conducted to facilitate directional liquid transport by constructing double-layered hydrophilic/hydrophobic materials, it remains difficult to achieve continuous water transport and reduce liquid wastage due to the hydrophilic regions. Herein, a directional water transport fabric (DWTF) was fabricated using a simple single-side coating method based on entirely hydrophobic materials. With coating thicknesses of 13–29 μm, the fabric could guide the continuous water motion from the coated to the uncoated side and can be utilized as a “liquid diode”. In addition, the DWTF exhibited a water wastage reduction during the transport process, benefiting from the intrinsic hydrophobic properties of the material. Moreover, a plausible mechanism of water transport is proposed to explain the water droplet transfer in the bilayered hydrophobic materials. Consequently, the resulting DWTF exhibited an excellent accumulative one-way transport capability (AOTC) of 965.7% and a desirable overall moisture management capability (OMMC) of 0.92. This work provides an avenue for fabricating smart fluid delivery materials to various applications such as flexible microfluidics, wound dressing, oil–water separation processes, and engineered desiccant materials.

The emission angle distribution of projectile fragments (PFs) and the temperature of PF emission sources for fragmentation of 56Feon polyethylene, carbon, and aluminum targets at the highest energy of 497 A MeV are investigated on the basis of corrected data, using a CR-39 plastic nuclear track detector. It is found that the average emission angle of PFs increases with the decrease in PF charge for the same target, and no obvious dependence of angular distribution on the mass of the target nucleus is found for the same PF. The cumulative squared transverse momentum distribution of PFs can be well represented by a single Rayleigh distribution. The temperature of PF emission sources is extracted from the distribution, and it is about 1.0–8.0 MeV and does not depend on the mass of the target for PFs with charges of 9≤Z≤25.