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Traffic load is one of the important external loads of bridges and simulating the site-specific traffic load is important for bridge condition assessment. This study proposes a new microscopic model to simulate the stochastic traffic load of any time period at bridge site based on weigh in motion (WIM) data. A model for simulating the microscopic interaction between vehicles was first proposed, by which free driving, car following and sudden braking can be reasonably simulated. Axle-weight information from the WIM data was embedded into the model to precisely simulate the vehicle load. A new vehicle sequence generation method based on WIM data was then proposed to generate the site-specific vehicle sequence of any time period with consideration of non-stationarity. Finally, a framework for simulating the site-specific stochastic traffic load is established. The proposed framework is validated through application based on realistic WIM data in traffic-flow simulation and load effect quantification. Comparisons of simulation results with the existing methods were also conducted to show the reasonability and novelty. The results indicate that the proposed framework can produce reasonable site-specific stochastic traffic load over any time period based on WIM data. [ABSTRACT FROM AUTHOR]

Identifying precursor information to rock failure is key to rock dynamic disaster warning. To solve the problem that a single in-situ monitoring method cannot accurately identify the precursors to rock failure, this paper combined a digital image correlation method, thermal infrared radiation and acoustic emission technology to conduct a multi-physical field joint monitoring experiment of granite under three-point bending. The information about strain, thermal infrared and acoustic emission of the rock brittle failure process could be obtained, and the variations in multi-physical field indices of the rock brittle failure process were analysed. Based on the theory of critical slowing-down, the study of the multi-physical field effects of critical slowing-down characteristics in the rock failure process, and further exploration of the precursor characteristics of the brittle failure of rock were undertaken. The results indicate that the strain, infrared, and acoustic emission parameters show sudden changes during brittle failure of granite. The lag step size has little effect on the variance of changes in multi-physical field parameters and exerts a similar influence on the changes in the autocorrelation coefficient curve. The degree of influence of the window length on the variance and autocorrelation coefficient curves of multi-physical field parameters is as follows: infrared field > strain field > acoustic emission field. Compared with the autocorrelation coefficient, the variance parameter is more universal and is better when the critical slowing-down theory is used to investigate the characteristics of multi-physical fields. The four parameters of the strain field variance, infrared field variance, the variance and autocorrelation coefficient for acoustic emission field increase sharply before fracture, representing precursor information to the brittle failure of granite. The four parameters can be used as disaster warning indicators in rock. Multi-mode joint monitoring and a comprehensive analysis of multi-physical information are beneficial to accurately determine the precursor points of rock failure disaster. [ABSTRACT FROM AUTHOR]

Identifying, tracking and warning of the vortexed induced vibration (VIV) are essential for long-span suspension bridges because VIV might cause the driving safety problem. This study proposes an automatic method to identify and track the start and evolution of the VIV. Two feature indices, i.e. the energy concentration coefficient (ECC) and similarity ratio of amplitude (SRA), are utilised to form a feature index vector to identify and track the VIV. The Hilbert transform is utilised to process the vibration signal, based on which the SRA can be extracted. The k-means clustering method is introduced to automatically identify and track the VIV through automatically separating the feature index vectors into several clusters, and multi-level warming is established based on the acceleration root mean square (ARMS) value. The proposed method is validated using the in-field monitoring data of a suspension bridge suffering the VIV. The results indicate that the proposed automatic method can successfully distinguish the VIV from ambient vibration and can identify the forming of the VIV and track the evolution without any manual intervention, even for the VIV with low vibration amplitude. The multi-level warning can also be achieved based on the ARMS value when the VIV is identified. [ABSTRACT FROM AUTHOR]

Abstract Heterostructures have excellent physicochemical properties, which have attracted much attention in photoelectrochemical and photocatalytic fields. Au-TiO2NTs and Au@TiO2NTs were fabricated by the impregnation method and a vacuum-assisted-impregnation route, respectively. The effects of Au position on the structural and photoelectrochemical properties and photocatalytic activity of TiO2 have been characterized and studied. The Au@TiO2NTs photoelectrode showed a significant photocurrent (∼17 μA/cm2), which was approximately 8.5 and approximately 2.3 times greater than that of TiO2NTs and Au-TiO2NTs. Meanwhile, Au@TiO2NTs also exhibited the best photocatalytic activity and stability for tetracyclines degradation. The characterization and experimental results revealed that the better performance of Au@TiO2NTs may be attributed to the smaller Au nanoparticles inside the nanotube space, the reduced interfacial charge transfer resistance, and the stronger electronic interaction between Au nanoparticles and TiO2NTs. [ABSTRACT FROM AUTHOR]

Studying the characteristics of tensile and shear cracks in a rockburst event is crucial for understanding the rockburst mechanism. In this study, several specimens were tested under biaxial compression, and the released acoustic emissions (AEs) of the resulting tunnel rockburst event were recorded. Based on the AE energy and dominant frequency parameters, the different AE characteristics and dominant frequency evolution law of tensile and shear cracks during the rockburst were analysed. According to the results, there are four types of AE signals in a rockburst event: low-frequency and low-energy signals, low-frequency and high-energy signals, medium-frequency and low-energy signals and high-frequency and low-energy signals. The low-frequency and low-energy signals are mainly generated by tensile cracks, and the low-frequency and high-energy signals originate from both tensile and shear cracks. The medium-frequency and low-energy signals and high-frequency and low-energy signals are often generated by tension cracks. The rockburst process can be classified into four stages: calm period, small-grain ejection period, sheet-like peeling period and violent ejection period. Before the occurrence of rockburst, both tensile and shear cracks produce low-frequency and high-energy signals. The low-frequency and high-energy (amplitude) AE signals are crucial for monitoring and early warning procedures for rockburst events. [ABSTRACT FROM AUTHOR]

Litopenaeus vannamei easily blackens during cold storage. To inhibit blackening and improve the storage quality of prawns, in this study, konjac glucomman (KGM)-epigallocatechin gallate (EGCG) topological microgel was formed and used for storage and preservation of prawns to improve their antioxidant properties. The effect of KGM-EGCG topological microgel on inhibiting shrimp blackening was studied by measuring the sensory evaluation score, pH value, TVB-N value, K value, PPO activity, and the effect of changes in the total number of bacteria of KGM-EGCG-treated prawns during storage. SEM and FTIR results showed that during the KGM-EGCG binding process, the number of hydrogen bond connections and the intermolecular force increased. Results also showed that the KGM microgel can effectively embed EGCG and enhance its stability to achieve a better controlled release effect. Compared with the EGCG group and untreated group, KGM-EGCG microgel has better anti-PPO activity and can better maintain the organoleptic quality and inhibit bacterial growth of Litopenaeus vannamei. Therefore, the KGM-EGCG microgel could slow down the increase in pH value, the production of volatile base nitrogen, and the increase in K value, and effectively extend the shelf life of Litopenaeus vannamei from 3 d to 6 d, providing a theoretical basis for the research of KGM functional gel and a reference for the deep processing and value enhancement of green tea and shrimp. [ABSTRACT FROM AUTHOR]

Spatial prediction is essential for obtaining the spatial distribution of geographic variables and selecting appropriate covariates for this process can be challenging, especially for non-expert users. For easing the burden of selecting the appropriate covariates, two case-based reasoning strategies, namely the most-similar-case and covariate-classification strategies, have been proposed for automated covariate selection. The former may suggest nonessential covariates due to its case-level reasoning way. And the latter with covariate-level reasoning may overlook related covariates and recommend fewer covariates than the case-level reasoning. In this study, we propose a new strategy of integrating case-level and covariate-level reasoning to effectively leverage the strengths of both previous strategies while also addressing their limitations. The proposed strategy is validated through a case study of automatically selecting covariates for digital soil mapping under reasoning with a case base containing 189 cases. The leave-one-out evaluation demonstrated that our proposed strategy outperformed the previous two strategies. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the composition of the fatty acids and phospholipids derived from large yellow croaker (Pseudosciaena crocea) roe. The composition of the total lipids and the molecular species of phospholipids were determined by gas chromatography–mass spectroscopy (GC–MS) and high performance liquid chromatography–evaporative light scattering detector (HPLC–ELSD), respectively. The results showed that large yellow croaker roe had high levels of the total lipid (19.6% ± 1.32%, w/w) and phospholipid (61.2% ± 1.22% of the total lipid). The phospholipid was rich in docosahexaenoic acid (31.0% ± 0.19% of the total phospholipids), and the major phospholipid molecular species was phosphatidylcholine (PC, 61.06% ± 0.02% of the total phospholipids, w/w). It was concluded that large yellow croaker roe is expected to be a good resource of phospholipids with a high content of PC. [ABSTRACT FROM PUBLISHER]

The objective of this study was to enhance the suitability of Lu’an coal for gasification in large entrained-flow gasifiers currently used by the Lu’an Group Mining Company in its 1.8 million ton per annum coal-based oil synthesis demonstration project. The effect of coal blending and flux addition on the ash fusion temperature (AFT) and gasification reactivity was investigated. CaO, Fe2O3, and MgO decreased the AFT of Lu’an coal by 150°C, 73°C, and 68°C, respectively, by a flux addition of up to 7%. Within the range of the experimental investigation, the AFT of Lu’an coal decreased by 3°C for each 1% of Shenmu coal addition. The gradual reduction of mullite and the formation of fayalite and hessonite in blended coal ash decreased the AFT. The addition of a fluxing agent significantly increased the reaction activity of the char, with Fe2O3exhibiting the largest catalytic effect on char gasification. Blending with Shenmu char significantly increased the gasification reactivity. The random pore model best describes the gasification process of Lu’an char, and a kinetic equation for the process was developed on the basis of this model. [ABSTRACT FROM PUBLISHER]

Existing GIS software mainly target at expert users and do not sufficiently integrate resources for efficient computing. They are difficult for non-experts to use and are often slow in completing the complicated geographic analysis. To address these problems, future generation of GIS software must be 'easy'. By 'easy' we mean 'easy to use' and 'easy to compute'. 'Easy to use' means that software system should be goal-oriented, rather than the currently procedure-oriented doctrine. The goal-oriented will relieve users, particularly novice users, the burden of knowing the exact commands and their sequences to perform for achieving the goal they want to achieve. 'Easy to compute' means that implementation of GIS analytical functionality should be able to utilize the high-performance computing infrastructures for complicated geographic analysis. Two case studies, one in digital soil mapping and the other in digital terrain analysis, are presented to illustrate the meaning of 'easy'. We believe that the future generations of GIS platforms should be goal-driven, intelligent, high-performance computing enabled, easily accessible, and participatory. It allows anyone to participate in geo-computation at anywhere and anytime. [ABSTRACT FROM AUTHOR]

This letter presents a novel method for unsupervised change detection (CD) from remote sensing images using level set evolution with local uncertainty constraints (LSELUC). Uncertainty analysis of pixel labels was implemented as prior information to guide the evolution of level curves. Then, local uncertainty and gradient information of level curves were incorporated into the level set energy function to construct local energy constraints. The proposed method can reduce noise, while preserving details in change regions. Furthermore, an advanced regularization strategy of the level set function was adopted to improve the computational efficiency. The performance of the proposed method was validated on two remote sensing data sets. Experimental results show that the proposed method can produce satisfactory CD results. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effect of the Maillard reaction (MR) on volatile flavor compounds of blue round scad (Decapterus maruadsi) enzymatic hydrolysate (BRSEH). Enzymatic hydrolysates combined with reducing sugars (xylose and glucose) and cysteine were kept at 100°C for 30 min to produce Maillard reaction products (MRPs). The volatile flavor compounds of enzymatic hydrolysates and MRPs were determined by gas chromatography-mass spectrometry. The results showed that 97 volatile flavor compounds were found in blue round scad meat and BRSEHs. Aldehyde compounds were the most abundant class of compounds produced by the enzymatic hydrolysis, and 2,4-heptadienal should be responsible for the rich fishy odor of BRSEHs. Through MR, the volatile fragrance substance content of MRPs showed an increase when compared with BRSEHs. Fifty-nine volatile compounds were found in MRPs, e.g., furans, pyrazines, and sulphur-containing compounds, all of which contributed to the flavor improvement of BRSEHs. The results indicate that MR could be utilized to broaden the application of blue round scad and to modify the flavor characters of BRSEH. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the most frequent primary liver cancer but has shown limited success to date in the treatment of advanced stage. Recruitment of T cells for cancer treatment is a rapidly growing strategy in immunotherapy such as chimeric antigen receptor T cells and bispecific antibodies. However, unwanted aggregations, structural instability or short serum half-life are major challenges of bispecific antibodies. Here, we developed a new format of T cell-redirecting antibody that is bispecific for membrane proteoglycans GPC3 of HCC and the T-cell-specific antigen CD3, which demonstrated to be favorable stability and productivity. Cross-linking of T cells with GPC3 positive tumor cells by the anti-GPC3/CD3 bispecific antibody-mediated potent GPC3-dependent and concentration-dependent cytotoxicity in vitro. Administration of the bispecific antibody with different concentrations in murine xenograft models of human HCC significantly inhibited tumor growth. In addition, no effects on tumor growth were observed in the absence of human effector cells or the bispecific antibody. Taken together, the anti-GPC3/CD3 bispecific antibody might be a potential therapeutic treatment for HCC. [ABSTRACT FROM AUTHOR]

For removing particulate pollutants from the coke burning tail gas of an ethylene pyrolysis furnace more effectively, a new parallel integrated cyclone separator has been devising and operating stably in the decoking system for five years. Industrial online supervision indicated that the separate efficiency of the equipment in collecting fine particulate pollutants from the ethylene pyrolysis furnace exceeded 95% and almost all of the larger coke particles are removed after cyclone separation. The volume of coke powder in the gas outlet accounts for only 2% of the total and the new parallel integrated cyclone separator ensuring the dust content of the exhausted tail gas to remain below required levels. [ABSTRACT FROM AUTHOR]

Two Zn(II)-containing complexes based on fluconazole, {[Zn(HFlu)2(IPA)]·9H2O}n(1), {[Zn(HFlu)2(OH-BDC)]·8H2O}n(2) (HFlu = fluconazole; 2-(2,4-difluoro- phenyl)-1,3-bis(1,2,4-triazol-1-yl)-propan-2-ol; H2IPA = isophthalic acid; OH-H2BDC = 5-hydroxyisophthalic acid) have been synthesized and structurally characterized. Complex1and2are both a one-dimensional (1D) tubular structure with the distorted dinuclear zinc rectangular-shaped cavity, and large free water molecules involved in strong O‒H···O and O‒H···N hydrogen bonds are accommodated in the 1D tubular structure. The thermal stabilities and photoluminescent properties of the coordination polymers have also been investigated. [ABSTRACT FROM AUTHOR]

Two new metal-organic frameworks, namely [Cd(3-NO2-bdc)(2,2′-bpy)(H2O)•H2O]2(1) and[Ni(3-NO2-bdc)(4,4′-bpy)H2O]n(2) (where 3-NO2-bdcH2= 3-nitro-1,2-benzenedicarboxylic acid, 2,2′-bpy = 2,2′-bipyridine, 4,4′-bpy = 4,4′-bipyridine), have been synthesized and structurally characterized. Complex 1 is a 0-dimensional (0D) framework, but face-to-face π-π stacking interactions and O–H···O hydrogen bonds extend these molecules into a 3D supramolecular framework. X-ray structure analysis reveals that complexes 2 exhibit a 2-dimensional (2D) network structure. Also, IR spectra, fluorescence properties, thermal decomposition process, and powder X-ray diffraction of the complexes were investigated. [ABSTRACT FROM PUBLISHER]