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Besides chiral edge states, the hallmark of quantum Hall insulators, antichiral edge states can exhibit unidirectional transport behavior but in topological semimetals. Although such edge states provide more flexibility for molding the flow of light, their realization usually suffers from time-reversal breaking. In this study, we propose the realization of antichiral surface states in a time-reversal-invariant manner and demonstrate our idea with a three-dimensional (3D) photonic metacrystal. Our system is a photonic semimetal possessing two asymmetrically dispersed Dirac nodal lines. Via dimension reduction, the nodal lines are rendered a pair of offset Dirac points. By introducing synthetic gauge flux, each two-dimensional (2D) subsystem with nonzero kz is analogous to a modified Haldane model, yielding a kz-dependent antichiral surface transport. Through microwave experiments, the bulk dispersion with asymmetric nodal lines and associated twisted ribbon surface states are demonstrated in our 3D time-reversal-invariant system. Although our idea is demonstrated in a photonic system, we propose a general approach to realize antichiral edge states in time-reversal-invariant systems. This approach can be easily extended to systems beyond photonics and may pave the way for further applications of antichiral transport.

Melt strength is crucial in foam-processing of polymer materials, especially for linear molecular structured isotactic polypropylene (iPP), which has comparatively weak melt strength to hinder its foaming. In this study, a commercial high melt strength polypropylene (HMSPP) was added into the iPP matrix, cooperated with a thermal treatment, aiming to enhance the melt strength and microcellular foamability of iPP under supercritical CO2. Melt strength enhancement effect was proved by rheological and microcellular foaming results. The crystallization and batch foaming behaviors of iPP and its HMSPP added blends at different foaming conditions were investigated. It was observed that the addition of HMSPP could refine the crystals of the blends, and the crystal nucleation sites could be increased apparently. Cooperated with the suitable thermal control schedule during the batch foaming process, the introduced crystals could correspondingly improve the melt strength and cell nucleating ability of HMSPP added iPP. At a given HMSPP content of 20 wt.%, quite fine microcellular foams with the average cell size of 0.8 μm, and cell density up to 1012 cells/cm3 were fabricated.

It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions. We have experimentally investigated $$^2 \hbox {H}({d},{p})^3 \hbox {H}$$, one of the most crucial reactions in big bang nucleosynthesis models, at the Shenguang-II laser facility. In this work, we present a new calibration of CR-39 solid-state track detectors, which are widely employed as the main diagnostics in this type of fusion reaction experiment. We measure the dependence of the track diameter on the proton energy. It is found that the track diameters of protons with different energies are likely to be identical. We propose that in this case, the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks. The present results would be very helpful for analyzing the $$^2 \hbox {H}(d,p)^3 \hbox {H}$$ reaction products recorded with the same batch of CR-39 solid-state track detectors.

Background Kümmell’s disease is a special type of osteoporotic vertebral fracture that causes chronic low back pain and deformity, which seriously affects the living quality of patients. PVP is commonly used to treat osteoporotic vertebral fractures and can quickly relieve low back pain. So, the objective of this study was to analyze the clinical efficacy and experience of bipedicular percutaneous vertebroplasty combined with postural reduction for the treatment of Kümmell’s disease. Methods A retrospective analysis of patients with Kümmell’s disease who underwent bipedicular percutaneous vertebroplasty was conducted from February 2016 to May 2018. Operative time, VAS, bone cement injection volume, cement leakage rate, compression improvement of vertebral front edge and vertebral center, and correction degree of kyphosis were collected and analyzed meticulously. Results The operative time was 45.33 ± 7.64 min. The volume of bone cement injected was 5.38 ± 1.33 ml. The compression improvement of vertebral front edge was 7.31 ± 1.21%. The compression improvement of vertebral center was 10.34 ± 1.15% and the correction degree of kyphosis was − 2.73 ± 0.31゜. Bone cement leakage occurred in 6 of 39 patients (15.38%), but no clinical symptoms were observed. The VAS scores were significantly lower at 1 day after the surgery, 6 months and at the last follow-up than before the surgery (P = 0.000, respectively). The VAS score was lower at the last follow-up than at 1 day after the surgery (P = 0.001). Conclusion Bipedicular percutaneous vertebroplasty combined with postural reduction could achieve satisfactory analgesic effect in the treatment of Kümmell’s disease, and restore the height of the vertebral body and improve kyphosis to some extent.

A series of CuMgAlOx mixed oxides with Cu content between 0 and 5 mol%, were obtained by the calcination of hyrotalcite-like precursors. The catalytic activity was evaluated by the coupling of methanol and ethanol. The physical and chemical properties of the catalysts were characterized by XRD, TG, XPS, N2O titration, in situ CO-DRIFTS, XPS, H2-TPR, NH3-TPD, and CO2-TPD techniques. The results show that with the increase of Cu content, the surface areas of exposed Cu species (Cu0 and Cu+) and the hydrogen dissociation abilities of the reduced catalysts increase, while the amount of the moderately basic sites decreases. The catalytic performance shows that the conversions of methanol and ethanol are strongly related to the surface areas of exposed Cu species. The STY of Guerbet products (C3 and C4 alcohols, aldehydes) is closely related to the surface exposed Cu species and the moderately basic sites, and the CHT-3 catalyst has a maximum of 125.01 g kg−1 h−1. Moreover, by-products including esters and CO2 also show a strong positive relationship with the surface areas of exposed Cu species.

It is important to track and reconstruct the complex immersed boundaries for simulating fluid structure interaction problems in an immersed boundary method (IBM). In this paper, a polynomial radial basis function (PRBF) method is introduced to the ghost cell immersed boundary method for tracking and reconstructing the complex moving boundaries. The body surfaces are fitted with a finite set of sampling points by the PRBF, which is flexible and accurate. The complex or multiple boundaries could be easily represented. A simple treatment is used for identifying the position information about the interfaces on the background grid. Our solver and interface reconstruction method are validated by the case of a cylinder oscillating in the fluid. The accuracy of the present PRBF method is comparable to the analytic function method. In ta flow around an airfoil, the capacity of the proposed method for complex geometries is well demonstrated.

The safety and efficacy of intraoperative chemotherapy in colorectal cancer have not yet been extensively investigated. This randomized control trial was designed to compare the safety and efficacy of intraoperative chemotherapy in combination with surgical resection to those of traditional surgical resection alone. From January 2011 to January 2016, 696 colorectal cancer patients were enrolled in this study: 341 patients were randomly assigned to the intraoperative chemotherapy, which consist of portal vein chemotherapy, intraluminal chemotherapy and intraperitoneal chemotherapy, plus surgery group, whereas 344 patients were randomized to the control group to undergo surgery alone. Eleven patients withdrew consent. Intraoperative chemotherapy did not increase the rate of surgical complications, and no severe chemotherapy-associated side effects were observed. Four patients in each of the intraoperative chemotherapy and the control groups experienced anastomotic leakage and underwent a second operation (1.2 vs. 1.2%, P = 0.99). There were no deaths within 90 days after surgery in the chemotherapy group, whereas one patient died in the control group. Intraoperative chemotherapy did not decrease the rate of patients who received postoperative chemotherapy between the intraoperative group and control group (29.3 vs. 30.2%, P = 0.795). Intraoperative chemotherapy can be safely performed during colorectal surgery; however, follow-up is necessary for a better assessment of its efficacy. ClinicalTrial.gov Register Number: NCT01465451.

Temperature rise is a significant factor influencing microstructure during (α + β) deformation of TA15 titanium alloy. An experiment was designed to explore microstructure evolution induced by temperature rise due to deformation heat. The experiment was carried out in (α + β) phase field at typical temperature rise rates. The microstructures of the alloy under different temperature rise rates were observed by scanning electron microscopy (SEM). It is found that the dissolution rate of primary equiaxed α phase increases with the increase in both temperature and temperature rise rate. In the same temperature range, the higher the temperature rise rate is, the larger the final content and grain size of primary equiaxed α phase are due to less dissolution time. To quantitatively depict the evolution behavior of primary equiaxed α phase under any temperature rise rates, the dissolution kinetics of primary equiaxed α phase were well described by a diffusion model. The model predictions, including content and grain size of primary equiaxed α phase, are in good agreement with experimental observations. The work provides an important basis for the prediction and control of microstructure during hot working of titanium alloy.

A lead-free glass frit paste as a die-attach material for high-temperature microelectronic application is proposed in this study. The glass paste containing Bi-based powder with a moderate amount of solvent was used for joining Si dice on ceramic substrates without any metallization preparation for either of the bonding surfaces. The die was bonded to a ceramic substrate at 430°C for 10 min. The study focuses on the mechanical and microstructural characterization of the joints with Si dice on two different types of ceramic substrate. Shear strength measurements were carried out at both ambient and 250°C to evaluate room- and high-temperature performance. Furthermore, the effect of aging at 300°C for 500 h on the mechanical properties is presented. The results of the mechanical and microstructural characterization demonstrate that low-temperature glass frit bonding is an effective die-attach method for harsh-environment electronic packaging.

Carbothermic reduction alumina in vacuum was conducted, and the products were analysed by means of XRD and gas chromatography. Thermodynamic analysis shows that in vacuum the initial carbothermic reduction reaction temperature reduces compared with that under normal pressure, and the preferential order of products is Al4O4C, Al4C3, Al2OC, Al2O and Al. Experiment results show that the carbothermic reduction products of alumina are Al4O4C and Al4C3, and neither Al2OC, Al2O or Al was found. During the carbothermic reduction process, the reaction rate of Al2O3 and carbon decreases gradually with increasing time. Meanwhile, lower system pressure or higher temperature is beneficial to the carbothermic reduction of alumina process. Al4O4C is firstly formed in the carbothermic reaction, and then Al4C3 is formed in lower system pressure or at higher temperature.

The behavior of silica was investigated experimentally in an alumina carbothermic reduction process and chlorination process in vacuum. The results showed that, first, SiC was produced by SiO2 and C, and then Al4SiC4 was produced by Al4C3, Al4O4C, C, and SiC during the alumina carbothermic reduction process at about 1,763 K. C, Al3C4 and Al4O4C decreased and Al4SiC4 increased as content of SiO2 increased. The following chlorination process was blocked, and the recovery rate of aluminum decreased quickly compared with that without silica. It was inferred that silica might be unfavorable for aluminum extracted from alumina by carbothermic reductionchlorination process in vacuum at about 1763 K.

A computational study for the [2 + 1] addition of the lithium carbenoids LiCH2X (X = Cl, Br, I) with ketene have been investigated by means of the B3LYP hybrid density functional method. All the reactions examined displayed similar concerted mechanisms for the cyclopropanation of these reagents. The lithium carbenoids react with ketene via an asynchronous attack on one CH2 or C group of ketene with relatively low barrier to reaction in the range of 25·34–33·74 kJ/mol in THF solvent. The trend of the lithium carbenoids reaction barrier with ketene is LiCH2Cl < LiCH2Br < LiCH2I. The results show that the reactions could be highly chemical reactivity with low barriers and could be favoured in experiment. The reactions could proceed easily at lower temperature. The computational results are briefly compared to other carbenoid reactions and related species.

Density functional theory calculations are reported for the reaction mechanism of selected XCuNHX(X = Cl, Br, I) with olefins to form three-membered ring products. The copper reagents react with olefins via an asynchronous attack on one CH2 group of ethylene with a relatively low barrier (

S-surface control has proven to be an effective means for motion control of underwater autonomous vehicles (AUV). However there are still problems maintaining steady precision of course due to the constant need to adjust parameters, especially where there are disturbing currents. Thus an intelligent integral was introduced to improve precision. An expert S-surface control was developed to tune the parameters on-line, based on the expert system, it provides S-surface control according to practical experience and control knowledge. To prevent control output over-compensation, a fuzzy neural network was included to adjust the production rules to the knowledge base. Experiments were conducted on an AUV simulation platform, and the results show that the expert S-surface controller performs better than an S-surface controller in environments with currents, producing good steady precision of course in a robust way.

Granites sampled from Garze-Litang thrust, Longmen Shan thrust, Garze and Litang strike-slip faults in the eastern Tibetan Plateau have been analyzed with apatite fission track thermochronological method in this study. The measured fission track apparent ages, combined with the simulated annealing modeling of the thermal history, have been used to reconstruct the thermal evolutionary histories of the samples and interpret the active history of the thrusts and faults in these areas. Thermal history modeling shows that earlier tectonic cooling occurred in the Garze-Litang thrust in Miocene (∼20–16 Ma) whereas the later cooling occurred mainly in the Longmen Shan thrust since ∼5 Ma. Our study suggests that the margin of eastern Tibetan Plateau was extended by stages: through strike-slip faults deformations and related thrusts, the upper crust formed the Garze-Litang margin in the Miocene epoch and then moved to the Longmen Shan margin since ∼5 Ma. During this process, the deformations of different phases in the eastern Tibetan Plateau were absorbed by the thrusts within them and consequently the tectonic events of long-distance slip and extrusion up to hundreds of kilometers have not been found.

Introduction Multimodality therapy, including preoperative chemoradiotherapy (CRT) and total mesorectal excision (TME), has effectively reduced local recurrence rates of rectal cancer over the past decade. However, the benefits and risks of the addition of neoadjuvant CRT to surgery need to be evaluated. This study was to compare the efficacy of TME with versus without preoperative concurrent chemoradiotherapy (CCRT) involving XELOX regimen (oxaliplatin plus capecitabine) in Chinese patients with stages II and III mid/low rectal adenocarcinoma. Methods We randomly assigned patients to the TME group (TME without preoperative CCRT) or CCRT + TME group (TME with preoperative CCRT). The primary endpoint was disease-free survival (DFS); the secondary endpoints were overall survival (OS), local and distant recurrence, tumor response to CRT, toxicity, sphincter preservation, and surgical complications. An interim analysis of the potential inferiority of DFS in the CCRT + TME group was planned when the first 180 patients had been followed up for at least 6 months. Results A total of 94 patients in the TME group and 90 patients in the CCRT + TME group were able to be evaluated. The 3-year DFS and OS rates were 86.3 % and 91.5 % in the whole cohort, respectively. The 3-year DFS rates of the TME and CCRT + TME groups were 85.7% and 87.9 % (P = 0.766), respectively, and the 3-year OS rates were 90.7 % and 92.3 % (P = 0.855), respectively. The functional sphincter preservation rates of the TME and CCRT + TME groups were 71.3 % and 70.0 % (P = 0.849), respectively. In the TME group, 16 (17.0 %) patients were proven to have pTNM stage I disease after surgery. In the CCRT + TME group, 32 (35.6 %) patients achieved a pathologic complete response (pCR). Conclusions Preliminary results indicated no significant differences in the DFS, OS, or functional sphincter preservation rates between the TME and CCRT + TME groups. However, preoperative CCRT with XELOX yielded a high pCR rate. Newer techniques are needed to improve the staging accuracy, and further investigation is warranted. Clinical trial registration number Chi CTR-TRC-08000122

One or more proteinaceous factors with insecticidal activities in the locust pathogen Serratia marcescens HR-3 culture filtrates were found to cause the death of grassland locusts. A novel insecticidal protein was purified to homogeneity. It was a monomer of 61 kDa. The purified protein showed a strong insecticidal effect with a median lethal dosage of 12.1 microg locust(-1) and contained a high level of protease activity (101 U ml(-1)). Insecticidal activity was significantly decreased when the protein was pretreated with ethylene diamine tetraacetic acid and 1-10-phenanthroline, and it was restored when the treated protein was incubated with Zn(2+). The N-terminal amino acid sequence of insecticidal protein showed sequence similarity with metalloprotease from S. marcescens SM6 and Serratia spp. E15. Our results suggested that the factor primarily responsible for insecticidal activity toward locusts was a zinc-dependent 61-kDa metalloprotease.