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The external bonding (EB) of fiber-reinforced polymer (FRP) is a usual flexural reinforcement method. When using the technique, premature debonding failure still remains a factor of concern. The effect of incorporating multi-wall carbon nanotubes (MWCNTs) in epoxy resin on the flexural behavior of reinforced concrete (RC) beams strengthened with basalt fiber-reinforced polymer (BFRP) sheets was investigated through four-point bending beam tests. Experimental results indicated that the flexural behavior was significantly improved by the MWCNT-modified epoxy. The BFRP sheets bonded by the MWCNT-modified epoxy more effectively mitigated the debonding failure of BFRP sheets and constrained crack development as well as enhanced the ductility and flexural stiffness of strengthened beams. When the beam was reinforced with two-layer BFRP sheets, the yielding load, ultimate load, ultimate deflection, post-yielded flexural stiffness, energy absorption capacity and deflection ductility of beams strengthened using MWCNT-modified epoxy increased by 7.4%, 8.3%, 18.2%, 22.6%, 29.1% and 14.3%, respectively, in comparison to the beam strengthened using pure epoxy. It could be seen in scanning electron microscopy (SEM) images that the MWCNTs could penetrate into concrete and their pull-out and crack bridging consumed more energy, which remarkably enhanced the flexural behavior of the strengthened beams. Finally, an analytical model was proposed for calculating characteristic loads and characteristic deflections of RC beams strengthened with FRP sheets, which indicated a reasonably good correlation with the experimental results.

Premature debonding failure is a critical problem in the reinforcement of concrete structures using fiber reinforced polymer (FRP) sheets with externally bonded reinforcement (EBR) technique. The usual anchoring methods are likely to cause damage to the concrete. The effect of incorporating various amounts of carboxyl (COOH)-functionalized MWCNTs in the epoxy resin on the bonding behavior of the basalt fiber-reinforced polymer (BFRP)-concrete joints was detailed studied by single-shear tests and the digital image correlation (DIC) technique. Experimental results indicated that adding the functionalized MWCNTs into the epoxy considerably enhanced the bonding properties. In comparison with the BFRP-concrete joints using neat epoxy, the effective bond length, bond strength, ultimate global slip, interface fracture energy, and BFRP strain of the BFRP-concrete joints using 0.8 wt% MWCNTs modified epoxy increased by 96 %, 55 %, 39 %, 172 %, and 114 %, respectively. The scanning electron microscope (SEM) images of debonded BFRP surface revealed that the MWCNTs could penetrate into concrete along with epoxy resin, and the MWCNTs pull-out and crack-bridging could indicate a reinforcing effect to prevent premature adhesive failure. This study demonstrated the great promise of the MWCNTs modified epoxy composites toward practical engineering application in reinforced concrete (RC) structures. Data availability statement: The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.

This study intends to predict the long-term skid resistance of steel slag asphalt mixture (SSAM) from the mineral composition of the aggregates. The polished stone value (PSV) and mineral composition of the aggregates were assessed using the accelerated polishing test and X-ray diffraction, respectively. The hardness (H) and surface texture richness (STR) of the aggregates were calculated from the mineral composition of the aggregates, and then a multivariate linear model was established between PSV and H and STR. The British pendulum number (BPN) and three-dimensional morphology of the SSAM were then evaluated using a British pendulum and a pavement laser scanner, respectively. Finally, an exponential relationship was established between BPN, aggregate PSV, and various aggregate amounts of SSAM. The results show that steel slag with H, STR, and PSV was better than natural aggregates and can significantly improve the skid resistance of pavement, but the relationship between steel slag content and long-term skid resistance of SSAM was not linear, and SSAM with 50% steel slag content had the best skid resistance. The mathematical model developed can predict the long-term skid resistance of SSAM from the mineral composition of the aggregates. The model can be used by designers to predict the long-term skid resistance of steel slag asphalt pavements at the design stage and thus better determine the proportion of steel slag to other aggregates.

Freeze-thaw cycles play a critical role in affecting ecosystem services in arid regions. Monitoring studies of soil temperature and moisture during a freeze-thaw process can generate data for research on the coupled movement of water, vapor, and heat during the freezing-thawing period which can, in turn, provide theoretical guidance for rational irrigation practices and ecological protection. In this study, the soil temperature and moisture changes in the deep vadose zone were observed by in-situ monitoring from November 2017 to March 2018 in the Mu Us Desert. The results showed that changes in soil temperatures and temperature gradients were largest in soil layers above the 100-cm depth, and variations decreased with soil depth. The relationship between soil temperature and unfrozen water content can be depicted well by both theoretical and empirical models. Due to gradients of the matric potential and temperature, soil water flowed from deeper soil layers towards the frozen soil, increasing the total water content at the freezing front. The vapor flux, which was affected mainly by temperature, showed diurnal variations in the shallow 20-cm soil layer, and its rate and variations decreased gradually with increasing soil depths. The freeze-thaw process can be divided into three stages: the initial freezing stage, the downward freezing stage, and the thawing stage. The upward vapor flux contributed to the formation of the frozen layer during the freezing process.

Chemical foaming concrete is a kind of new building material. In this paper, the quasi-static conditions of foam concrete and dynamic mechanical properties under impact dynamic conditions are studied. This paper also analyzes in detail the damage mechanism, deformation characteristics and energy absorption characteristics of the foam concrete under compression and stretch conditions. The results indicate that, the lower the density is, the less the cells on the surface and the inside of the concrete material is, and the larger the diameter of the pores is. When the density increases, the number of cells increases as well, and the diameter of the pores decrease gradually. The whole process of uniaxial compression of foam concrete is divided into three stages, that is, the material's elasticity and plasticity stage, platform stage and material densification stage. In the initial stage of stretch and compression, the stress-strain curve of foam concrete increases linearly basically. In platform stage, the foam concrete is mainly absorbing the energy, and there are both strain- softening and strain-hardening behaviors in this stage at the same time. The greater the density of the concrete, the earlier the densification stage occurs. The research on the impact dynamic properties of foam concrete shows that the dynamic strain rate is obviously positively correlated with the impact velocity, i.e., the greater the impact velocity, the greater the strain rate. The dynamic stress-strain curve of foam concrete is almost the same as that of static curve. It is also divided into three stages: linear elastic stage, material yield stage and material failure stage.

This paper presents an automated tool for floating-point to fixed-point conversion. The tool is based on previous work that was built in MATLAB/Simulink environment and Xilinx System Generator support. The tool is now extended to include Synplify DSP blocksets in a seamless way from the users' view point. In addition to FPGA area estimation, the tool now also includes ASIC area estimation for end-users who choose the ASIC flow. The tool minimizes hardware cost subject to mean-squared quantization error (MSE) constraints. To obtain more accurate ASIC area estimations with synthesized results, 3 performance levels are available to choose from, suitable for high-performance, typical, or low-power applications. The use of the tool is first illustrated on an FIR filter to achieve over 50% area savings for MSE specification of 10~6 as compared to all 16-bit realization. More complex optimization results for chip-level designs are also demonstrated. [ABSTRACT FROM AUTHOR]

Examines whether piezoelectric polarization is associated with dislocations in wurtzite gallium nitride (GaN). Dislocations on either carrier scattering or doping distribution; Polarization vector associated with a pure screw dislocation; Dislocation geometries and resultant polarizations.

Background: Pembrolizumab shows robust antitumor activity and favorable safety in metastatic melanoma. KEYNOTE-151 evaluated pembrolizumab in Chinese patients, who have more aggressive melanoma subtypes than other populations., Methods: Chinese patients aged ≥18years with advanced melanoma previously treated with one line of therapy received pembrolizumab 2 mg/kg every 3 weeks for 35 cycles or until confirmed disease progression, intolerable toxicity, or study withdrawal. Primary end points were objective response rate (ORR) per RECIST v1.1 by blinded independent central review and safety. Key secondary end points included duration of response (DOR) and progression-free survival (PFS) per RECIST v1.1 and overall survival (OS)., Results: Median age was 52 years (N=103); 37.9% had acral and 14.6% had mucosal melanoma. Median follow-up was 7.9months at data cutoff (December 27, 2017). ORR was 16.7% (95% CI, 10.0-25.3%) (1 complete, 16 partial responses). Disease control rate was 38.2%. ORR was 15.8% for acral, 13.3% for mucosal melanoma. Median DOR was 8.4months; 65.6% of patients had response duration ≥6months. Median PFS was 2.8months (95% CI, 2.7-3.5months); 6-month rate was 20.4%. Median OS was 12.1months (95% CI, 9.6months-not reached); 6-month rate, 75.7%; 12-month rate, 50.6%. Treatment-related AEs (TRAEs) occurred in 87 (84.5%) patients; 9 (8.7%) experienced grade 3/4 TRAE and 2 (1.9%) discontinued because of TRAE; none died. Two deaths occurred that were unrelated to treatment., Conclusions: Pembrolizumab was well tolerated and provided clinically meaningful antitumor activity as second-line therapy in Chinese patients with advanced melanoma., (Copyright © 2019. Published by Elsevier Inc.)

Listeria monocytogenes (L. monocytogenes), an important food-borne pathogenic microorganism, has resistance immune function to many commonly used drugs. Myristic acid is a traditional Chinese herbal medicine, but it has been rarely used as a food additive, limiting the development of natural food preservatives. In this study, the antibacterial activity and mechanism of myristic acid against L. monocytogenes were studied. The minimum inhibitory concentration (MIC) of myristic acid against 13 L. monocytogenes strains ranged from 64 to 256 μg ml -1 . The time-kill assay demonstrated that when myristic acid was added to dairy products, flow cytometry confirmed that myristic acid influenced cell death and inhibited the growth of L. monocytogenes. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and NPN uptake studies illustrated that myristic acid changed the bacterial morphology and membrane structure of L. monocytogenes, which led to rapid cell death. Myristic acid could bind to DNA and lead to changes in DNA conformation and structure, as identified by fluorescence spectroscopy. Our studies provide additional evidence to support myristic acid being used as a natural antibacterial agent and also further fundamental understanding of the modes of antibacterial action.

Arctigenin (ARG) is a functional active component that has important physiological and pharmacological activities. The anti-tumour and anti-inflammatory activities of ARG show good potential for application and development, but this material has the defect of low water solubility. In this experiment, the valine derivative of ARG (ARG-V) was designed and synthesized to overcome this disadvantage. The ARG amino acid, EDCI and DMAP were raw materials in the addition reaction, with a molar ratio of 1:2:2:0.5. The yield of ARG-V was up to 80%. ARG-V has strong anti-tumour activity in vivo and in vitro. The inhibitory rate of ARG-V was 69.2%, with less damage to the immune organs and different degrees of increased serum cytotoxicity. Moreover, the pharmacokinetics of ARG following oral administration and ARG-V following oral administration in rats were also studied. The C max and AUC values of ARG-V showed significant differences compared to ARG. The relative bioavailabilities of three doses of ARG-V compared to ARG were 664.7%, 741.5% and 812.9%. These pharmacokinetic results may be useful for further studies of the bioactive mechanism of ARG and provide a theoretical basic for clinical use.

Objective: Alpha-synuclein (AS) accumulation identified by immunohistochemistry (IHC) of gastrointestinal (GI) tract biopsies is considered as a potential pathologic biomarker for Parkinson's disease (PD). We compared AS IHC findings in biopsy specimens and surgically resected full-depth specimens to examine the reliability of GI tract biopsies., Methods: We included patients with PD who had undergone operation of the GI tract for treatment of tumors. Controls were matched with age at operation, gender, and surgical resection site. We compared AS accumulation using phosphorylated AS (pAS) IHC between patients and controls, and within individuals between surgical and biopsy specimens., Results: A total of 33 patients with PD were categorized into either the stomach (N = 12) or colorectal group (N = 21). The frequency of pAS positivity in gastric surgical specimens was 58.3% (7/12) and 8.3% (1/12) in the patient and control groups, respectively (p = 0.027). The frequency of pAS positivity in colorectal surgical specimens was identical in the patient and control group (23.8% [5/21] in each). Intriguingly, immunostaining results for biopsy specimens were not concordant with those for surgical specimens. There was no significant difference in the frequency of pAS positivity in biopsy specimens between patients and controls (9.1% [2/22] vs 18.2% [4/22]; p = 0.664)., Interpretation: Our results demonstrate that AS accumulation identified via pAS IHC of GI biopsies is unreliable due to its low positive rates and poor concordance with surgical specimens, and that future studies investigating AS accumulation in the GI tract should target the stomach, rather than the colon or rectum., (Copyright © 2017. Published by Elsevier Ltd.)

Effects of protopanaxdiol (PDG) and protopanaxatriol (PTG) types of ginsenosides isolated from the leaves of American ginseng on porcine pancreatic lipase activity were determined in vitro. PDG inhibited the pancreatic lipase activity in a dose-dependent manner at the concentrations of 0.25-1mg/ml. It inhibited hydrolysis of about 83.2% of triolein at about 1mg/ml of PDG. However, PTG showed no inhibitory activity. Therefore, anti-obesity activity of PDG was evaluated in mice fed a high-fat diet. The results demonstrated that PDG was effective in preventing and healing obesity, fatty liver and hypertriglyceridemia in mice fed with a high-fat diet., (Copyright © 2010 Elsevier B.V. All rights reserved.)