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The Al–Mn alloy heat exchanger fin production process includes a brazing treatment at s high temperature of 600 °C, in which coarse grains are preferred for their high resistance to deformation at elevated temperatures by decreasing the grain boundary sliding. In this study, Al-1.57Mn-1.57Zn-0.58Si-0.17Fe alloy foils cold rolled by 81.7% (1.1 mm in thickness) and 96.5% (0.21 mm in thickness) were annealed at 100–550 °C for 1 h to investigate their recrystallization behavior, grain sizes, and precipitates by increasing the annealing temperature, using micro-hardness measurement, electron back-scattered diffraction (EBSD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The micro-hardness results showed that the recrystallization finishing temperatures for the two samples were almost the same, 323 ± 2 °C. The EBSD results showed that when the annealing temperature decreased from 550 to 400 °C, the recrystallized grain sizes of the two samples were nearly identical—both increased slightly. Further decreasing the annealing temperature from 400 to 330 °C caused the grain sizes to increase more, with the thinner foil sample having a more significant increase. The SEM and TEM observations showed that the micron-sized primary-phase remained unchanged during the annealing process. The nano-sized secondary phase precipitates formed during the hot-rolling process experienced a coarsening and dissolving process upon annealing. The particle size of the secondary phase increased from 32 nm to 44 nm and the area fraction decreased from 4.2% to 3.8%. The nucleation analysis confirmed that the large primary-phase could act as a nucleation site through particle stimulated nucleation (PSN) mode. The relatively dense secondary phase precipitates with small sizes at lower temperatures could provide higher Zener drag to the grain boundaries, leading to fewer nuclei and thereafter coarser grains. The coarsening of the recrystallized grains in the foils could be implemented through thickness reduction and/or precipitation processes to form densely distributed nano-sized precipitates. [ABSTRACT FROM AUTHOR]

Rail surface defects are potential danger factors for railway systems, and visual inspection of surface defects plays a vital role in rail maintenance. Recently, the methods based on deep learning have been widely used in rail inspection systems, but such systems often face the problem of a lack of defect samples for training deep learning models at start‐up, which is called the cold‐start problem. It is challenging to obtain sufficient defect samples since defects are sparse and even non‐existent for a running railway system. Therefore, a synthetic‐to‐realistic domain adaptation (SRDA) method is proposed for real‐world rail inspection. SRDA adapts synthetic images to look more realistic for reducing the domain gap between synthetic images and realistic rail surface images and obtains translated images that consist of synthetic defect information and realistic rail background. After that, the translated images are used to train a detector for rail inspection of rail surface defects. In order to make the detector more robust to complex backgrounds, SRDA generates images with the same defect‐level semantics but with different texture appearances and makes the detector align these images in the learned feature space. In addition, the synthetic and realistic rail surface defects (SRRSD) dataset containing 20,662 images is built. The experimental results on SRRSD show that SRDA achieves higher detection performance than other established domain adaption methods with 19.0% for F1score${\mathrm{F}}1\ {\mathrm{score}}\ $ and 26.7% for average precision. [ABSTRACT FROM AUTHOR]

Automated infrastructure monitoring systems play a vital role in ensuring transportation safety and have been studied extensively in the literature. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, this paper conducts literature review to investigate the stereoscopic monitoring of transportation infrastructure. Based on the specific inclusion criteria, a total of 137 publications are systematically reviewed. Different from most of existing work that focus on either specific infrastructure or monitoring technique, this survey provides a stereoscopic monitoring perspective for the first time, and simultaneously reviews the fundamentals and applications of representative satellite, aerial, ground, and body-based monitoring techniques for roads, bridges and tunnels. Beyond that, the future research trends are discussed in the conclusion. • A stereoscopic perspective for transportation infrastructure monitoring was proposed. • Fundamentals and applications of representative monitoring techniques were systematically reviewed. • Roads, bridges, and tunnels were simultaneously considered. • Future research trends on stereoscopic monitoring of transportation infrastructure were outlined. [ABSTRACT FROM AUTHOR]

Vehicles carrying hazardous material (hazmat) are severe threats to the safety of highway transportation, and a model that can automatically recognize hazmat markers installed or attached on vehicles is essential for intelligent management systems. However, there is still no public dataset for benchmarking the task of hazmat marker detection. To this end, this paper releases a large-scale vehicle hazmat marker dataset named VisInt-VHM, which includes 10,000 images with a total of 20,023 hazmat markers captured under different environmental conditions from a real-world highway. Meanwhile, we provide an compact hazmat marker detection network named HMD-Net, which utilizes a revised lightweight backbone and is further compressed by channel pruning. As a consequence, the trained-model can be efficiently deployed on a resource-restricted edge device. Experimental results demonstrate that compared with some established methods such as YOLOv3, YOLOv4, their lightweight versions and popular lightweight models, HMD-Net can achieve a better trade-off between the detection accuracy and the inference speed. [ABSTRACT FROM AUTHOR]

Rail surface inspection using visual inspection system is an important part of railway maintenance. However, accurate and efficient identification of possible defects remains challenging. This paper proposes a background-oriented defect inspector (BODI) to improve defect detection by considering specified characteristics of the track during inspection. Reformulating the inspection task in this manner offers a new way to model rail surface images. More specifically, BODI features a random sampling stage to obtain a compact background representation without any prior information. A sufficient number of random selections generates adequate and diverse background statistics, and defect-determination and a fusion of procedures then determine whether current pixel belongs to the background. Finally, a background update mechanism and parallelism ensure real-time applicability. The proposed BODI is evaluated on a working railway line. The experimental results demonstrate that it outperforms state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Stable carbon and nitrogen isotope values (δ13C and δ15N) were used to evaluate trophic niche overlap between two filter-feeding fishes (known together as bigheaded carp) native to China, silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), and three native filter-feeding fish including bigmouth buffalo (Ictiobus cyprinellus), gizzard shad (Dorosoma cepedianum) and paddlefish (Polyodon spathula) in the lower Missouri River, USA, using the Bayesian Stable Isotope in R statistics. Results indicate that except for bigmouth buffalo, all species displayed similar trophic niche size and trophic diversity. Bigmouth buffalo occupied a small trophic niche and had the greatest trophic overlap with silver carp (93.6%) and bighead carp (94.1%) followed by gizzard shad (91.0%). Paddlefish had a trophic niche which relied on some resources different from those used by other species, and therefore had the lowest trophic overlap with bigheaded carp and other two native fish. The trophic overlap by bigheaded carp onto native fish was typically stronger than the reverse effects from native fish. Average niche overlap between silver carp and native species was as high as 71%, greater than niche overlap between bighead carp and native fish (64%). Our findings indicate that bigheaded carps are a potential threat to a diverse and stable native fish community. [ABSTRACT FROM AUTHOR]

For recycling waste refractory materials in metallurgical industry, porous alumina ceramics were prepared via pore forming agent method from α-Al 2 O 3 powder and slide plate renewable material. Effects of slide plate renewable material (SPRM) on densification, mechanical strength, thermal conductivity, phase composition and microstructure of the porous alumina ceramics were investigated. The results showed that SPRM effectively affected physical and thermal properties of the porous ceramics. With the increase of SPRM, apparent porosity of the ceramic materials firstly increased and then decreased, which brought an opposite change for the bulk density and thermal conductivity values, whereas the bending strength didn’t decrease obviously. The optimum sample A2 with 50 wt% SPRM introducing sintered at 1500 °C obtained the best properties. The water absorption, apparent porosity, bulk density, bending strength and thermal conductivity of the sample were 31.7%, 62.8%, 1.71 g/cm 3 , 47.1 ± 3.7 MPa and 1.73 W/m K, respectively. XRD analysis indicated that a small quantity of silicon carbide and graphite in SPRM have been oxidized to SiO 2 during the firing process, resulting in rising the porous microstructures. SEM micrographs illustrated that rod-like mullite grains combined with plate-like corundum grains to endow the samples with high bending strength. This study was intended to confirm the preparation of porous alumina ceramics with high porosity, good mechanical properties and low thermal conductivity by using SPRM as pore forming additive. [ABSTRACT FROM AUTHOR]

Carbon and nitrogen stable isotopes (δ 13 C and δ 15 N) have been used as indicators for environmental changes in aquatic ecosystems. In this study, δ 13 C and δ 15 N values of select flora taxa were evaluated as indicators of human-induced eutrophication in an Everglades wetland which has been impaired by the source and quality of inflow and the alteration of hydrological pattern. Results showed that δ 13 C of cattail ( Typha domingensis Pers.) increased with the decrease in total phosphorus (TP) concentration. Limited data for sawgrass ( Cladium jamaicenses Crantz) collected at three study sites along the nutrient gradient also show a similar change in δ 13 C. However, δ 13 C of periphyton and bladderwort ( Utricularia sp.) decreased with the decrease in TP concentration. The elevated δ 13 C values of emergent vascular plants (cattail and sawgrass) were likely the results of decreases in stomatal conductance, carboxylation and 13 C fractionation under nutrient stress. This is supported by corresponding decreases in photosynthetic rate of cattail along the decreasing nutrient gradient. In contrast, δ 15 N values of all flora taxa increased with the increase in TP concentration. Findings from this study indicate that δ 13 C of emergent plants is a sensitive indicator for nutrient stress while δ 15 N of major flora species may serve as a robust indicator for wetland eutrophication. [ABSTRACT FROM AUTHOR]

Understanding the carbon sources supporting aquatic consumers in large rivers is essential for the protection of ecological integrity and for wildlife management. The relative importance of terrestrial and algal carbon to the aquatic food webs is still under intensive debate. The Yangtze River is the largest river in China and the third longest river in the world. The completion of the Three Gorges Dam (TGD) in 2003 has significantly altered the hydrological regime of the middle Yangtze River, but its immediate impact on carbon sources supporting the river food web is unknown. In this study, potential production sources from riparian and the main river channel, and selected aquatic consumers (invertebrates and fish) at an upstream constricted-channel site (Luoqi), a midstream estuarine site (Huanghua) and a near dam limnetic site (Maoping) of the TGD were collected for stable isotope (δ13C and δ15N) and IsoSource analyses. Model estimates indicated that terrestrial plants were the dominant carbon sources supporting the consumer taxa at the three study sites. Algal production appeared to play a supplemental role in supporting consumer production. The contribution from C4 plants was more important than that of C3 plants at the upstream site while C3 plants were the more important carbon source to the consumers at the two impacted sites (Huanghua and Maoping), particularly at the midstream site. There was no trend of increase in the contribution of autochthonous production from the upstream to the downstream sites as the flow rate decreased dramatically along the main river channel due to the construction of TGD. Our findings, along with recent studies in rivers and lakes, are contradictory to studies that demonstrate the importance of algal carbon in the aquatic food web. Differences in system geomorphology, hydrology, habitat heterogeneity, and land use may account for these contradictory findings reported in various studies. [ABSTRACT FROM AUTHOR]

As natural tracers, stable isotopes have been extensively used in plant physiological, ecological and environmental research. Recently, animal physiological ecologists have also applied stable isotope techniques to study plantanimal relationships. The isotopic compositions of animal body generally reflect and integrate their diets over a time period ranging from hours to years to the lifetime of an individual. When animal living habitat changes or animals move to a new environment, the animal isotopic compositions will shift accordingly. Thus, stable isotope signatures of an animal can truly reflect its food sources, habitat, distribution and movement patterns during a given time period. Moreover, by analyzing animal-tissue isotopic compositions at different temporal scales, we can improve our understanding of animal adaptation to environmental changes. Stable isotope technique also provides an ideal tool to study animal foodweb relationship and community structure because of isotopic fractionation during the processes of nutrient assimilation by animals. Stable isotope technique can continuously measure animal trophic position in a foodweb, which can eventually reveal the predator-prey relationship and its role in determining matter balance and energy flow in the entire ecosystem. Stable isotope technique has been one of the most important and efficient tools in studying plant-animal relationship. In this paper, we first review recent advances in the application of stable isotope techniques to plant-animal relationship research then evaluate their advantages and disadvantages, and finally discuss some future directions associated with stable isotope applications to plant-animal relationship research. [ABSTRACT FROM AUTHOR]

Deep neural networks, including deep auto-encoder (DAE) and generative adversarial networks (GAN), have been extensively applied for visual anomaly detection. These models generally assume that reconstruction errors should be lower for normal samples but higher for anomalies. However, it has been found that DAE based models can sometimes reconstruct anomalies very well and thus result in false alarms or misdetections. To address this problem, we propose a model using GAN with locality-preferred recoding, named LRGAN. LRGAN is inspired by the observation that both normal and abnormal samples are not completely scattered throughout the latent space but clustered separately at some local regions. Therefore, a locality-preferred recoding (LR) module is designed to compulsively represent the latent vectors of anomalies by normal ones. As a result, reconstructions of anomalies will approximate to normal samples and corresponding residuals can thus be enlarged. To partly avoid latent vectors of normal samples being recoded, we further present an improved model using GAN with an adaptive LR (ALR) module, named LRGAN+. ALR applies the clustering algorithm to generate a more compact codebook; more importantly, it helps LRGAN + automatically skip the LR module for possible normal samples with a threshold strategy. Our proposed method is evaluated on two public datasets (i.e., MNIST and CIFAR-10) and one real-world industrial dataset (i.e., Fasteners), considering both one-class and multi-class anomaly detection protocols. Experimental results demonstrate that LRGAN is comparable with state-of-the-art methods and LRGAN + outperforms these methods on all datasets. [ABSTRACT FROM AUTHOR]

Activated hepatic stellate cells (HSCs) have a central role in the progression of liver fibrosis and express a large amount of secreted protein, acidic and rich in cysteine (SPARC), a specific protein-binding protein. In this study, we reported the preparation and evaluation of naringenin (Nar) -loaded albumin self-modified liposomes (NaAlLs), which delivered Nar, a specific Smad3 inhibitor that blocked the TGF-β/Smad3 signaling pathway and played an anti-fibrosis role. After a series of characterization, it was found that NaAlLs had favorable dispersion (PDI < 0.15) with an average particle size of about 120 nm and high entrapment efficiency (>85%), albumin coated the surface of liposomes or embedded in phospholipid bilayer by interaction with the encapsulated naringenin and phospholipid molecules during the preparation of liposomes. The amount of albumin modified to the surface of NaAlLs by this method is not only more than that of the physical adsorption method, but also the binding force between albumin and liposomes is stronger. The albumin modified to the surface of NaAlLs greatly reduced the aggregation of liposomes and drug leakage and increased the stability of liposomes. More importantly, the uptake of NaAlLs by activated HSCs was 1.5 times higher than that of Nar-loaded liposomes (NaLs), suggesting that NaAlLs specifically increased targeting of activated HSCs via albumin and SPARC-dependent pathways. As expected, NaAlLs was more effective in improving liver fibrosis than the NaLs or the inclusion complex solution of Nar and Hydroxypropyl-β-cyclodextrin (NaICS). The results suggested that NaAlLs was a promising drug delivery system, which could target drug delivery to activated HSC for the treatment of liver fibrosis. [ABSTRACT FROM AUTHOR]

The crystal structure, orientation, reduced modulus, and hardness of Al 3 Sc single crystal were studied using X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and nanoindentation techniques, combined with Hertzian elastic theory method (Hertz) and Oliver-Pharr method (O&P). Millimeter-sized Al 3 Sc single crystals were prepared using quasi-equilibrium solidification of hypereutectic Al-15(wt %) Sc alloy. The XRD results showed that the samples were composed of L1 2 -Al 3 Sc and Al phases. The EBSD and nanoindentation results showed that for five Al 3 Sc single crystals with different orientations, the reduced moduli measured by Hertz method were 146.6 ± 0.4–148.3 ± 0.2 GPa; while measured by O&P method they were 147 ± 2–150 ± 3 GPa. The corresponding hardnesses were varied between 3.8 ± 0.1 and 3.9 ± 0.1 GPa. The Poisson's ratio and elastic constants were determined through iterative calculation based on the relationship between the reduced modulus and Young's modulus at various orientations. The polycrystal elastic properties, bulk modulus, shear modulus and Young's modulus, were determined. The elastic constants c11, c12, and c44 were 179.2 ± 0.4, 44.1 ± 0.1, and 68.3 ± 0.3 GPa, respectively; the Poisson's ratio was 0.196 ± 0.001. The Young's modulus of five Al 3 Sc single crystals oriented in different directions was in the narrow range 161–164 GPa. The anisotropy factor of Al 3 Sc crystal was 1.011 ± 0.002, confirming that it is elastically isotropic. These results provide fundamental information for the research and development of the Al 3 Sc intermetallic compound and related alloys in future. • Millimeter-sized Al 3 Sc single crystals were made by quasi-equilibrium solidification. • The reduced moduli of Al 3 Sc single crystals were measured by nanoindentation. • The elastic constants and Poisson's ratio were determined by iterative calculation. • The elastic properties of Al 3 Sc single crystals are determined to be isotropic. [ABSTRACT FROM AUTHOR]

There is minimal published research information on optimal fertilizer rates for growing organic herbs in a greenhouse container system under warm climate in south Florida. Our objective was to determine the optimum organic fertilizer rate for container herb production in a greenhouse for basil (Ocimum basilicum), coriander (Coriandrum sativum), and dill (Anethum graveolens) using Perdue certified organic fertilizer (Agri Recycle, 4-2-3, Seaford, DE) (4N-0.85P-0.25K). The organic fertilizer was mixed with potting medium (Fafard, Conrad Fafard, Inc.; Agawam, MA) at four rates: 0, 10.6, 21.1, and 31.7 g of fertilizer per L of potting medium. Results indicated an increase in nitrogen in plant tissue with an increase in fertilizer rate for all herbs and both trials. Based on statistical results from the fresh and dry weights of the herbs, the Purdue fertilizer rate for optimum production should be between 21.1 and 31.7 g of fertilizer per L of potting media. The lower fertilizer rate (21.1 g) is more attractive for overall production since it would result in a lower cost than using the 31.7 g fertilizer rate. This recommendation is based on the fertilizer chosen, the herb, the potting media, and the location of this study. [ABSTRACT FROM AUTHOR]

The nucleation and growth processes of pure Fe/pure Al intermetallic compounds (IMCs) during heat treatment at 380 °C and 520 °C were observed through in situ scanning electron microscopy (SEM). The size of the IMCs were statistically analyzed using image analysis software. The types and distribution of IMCs were characterized using transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD). The results showed that: at 380 °C, the primary phase of the Fe/Al composite intermetallic compounds was Fe4Al13, formed on the Fe side and habituated with Fe. The IMC was completely transformed from the initial Fe4Al13 to the most stable Fe2Al5, and the Fe2Al5 was the habitus with Fe during the process of holding at 380 °C for 15 min to 60 min. At 380 °C, the initial growth rate of the IMC was controlled by reaction, and the growth rate of the thickness and horizontal dimensions was basically the same as 0.02–0.17 μm/min. When the IMC layer thickness reached 4.5 μm, the growth rate of the thickness changed from reaction control to diffusion control and decreased to 0.007 μm/min. After heat treatment at 520 °C (≤20 min), the growth of IMC was still controlled by the reaction, the horizontal growth rate was 0.53 μm/min, the thickness growth rate was 0.23 μm/min, and the main phase of the IMC was the Fe2Al5 phase at 520 °C/20 min. [ABSTRACT FROM AUTHOR]

Vehicles transporting hazardous material (HAZMAT) pose a severe threat to highway safety, especially in road tunnels. Vehicle reidentification is essential for identifying and warning abnormal states of HAZMAT vehicles in road tunnels. However, there is still no public dataset for benchmarking this task. To this end, this work releases a real-world tunnel HAZMAT vehicle reidentification dataset, VisInt-THV-ReID, including 10,048 images with 865 HAZMAT vehicles and their spatiotemporal information. A method based on multimodal information fusion is proposed to realize vehicle reidentification by fusing vehicle appearance and spatiotemporal information. We design a spatiotemporal similarity determination method for vehicles based on the spatiotemporal law of vehicles in tunnels. Compared with other reidentification methods based on multimodal information fusion, i.e., PROVID, Visual + ST, and Siamese-CNN, experimental results show that our approach significantly improves the vehicle reidentification recognition precision. [ABSTRACT FROM AUTHOR]

Flutter design is important for the design of new aircraft types, for which flutter tests are an important verification measure. Atmospheric turbulence excitation is a common form of excitation in flutter flight tests. The modal parameter estimation of the turbulence response is a key aspect to ensure accurate data processing of flutter test results. Atmospheric turbulence excitation acts on the structural system, and the turbulence response thus simultaneously contains both the randomness of the excitation signal and the determinism of the structure system. In view of the turbulence response characteristics, this paper addresses the incoherence of atmospheric turbulence excitation and the orthogonality of the frequency domain from a multichannel response. The turbulence response is used to perform modal parameter identification in the frequency domain. The power spectral density matrix can be calculated from the multichannel turbulence response using the periodogram method. Singular value decomposition is then performed on the power spectral density matrix at each spectral pin based on the orthogonality of the frequency domain. The maximum singular value of each spectral pin forms a curve over the entire frequency band, which is the autopower spectral density function of the system, the system is directly identified at the frequency domain using the polynomial fitting in the frequency domain, and the modal parameters (frequency, damping ratio) are calculated according to the fitted transfer function. This paper verifies the theoretical feasibility of the proposed method using simulation data. The engineering applicability is verified based on the turbulence response from the flutter flight test of a certain aircraft type. [ABSTRACT FROM AUTHOR]

Asphalt pavement performs viscoelastic-viscoplastic behavior under traffic loadings during its service life. The heterogeneous internal structure formed by the randomly distributed aggregates makes the viscoplastic behavior of the asphalt mixture unpredictable, which limits the improvement of the service performance of asphalt pavements. To this end, this study proposed a viscoelastic-viscoplastic homogenization method using the Mori-Tanaka theory that incorporates the viscoplastic behavior of asphaltic materials. Based on the volume contents of the elastic aggregate inclusions and the viscoelastic-viscoplastic asphalt mortar matrix within asphaltic composites, the homogeneous viscoelastic performances in the linear stage and viscoplastic behavior in the nonlinear stage can be effectively predicted. In addition, the shape features of aggregate inclusion can be considered by specifying the axial lengths in the homogeneous method. Combined with the locally homogeneous models in previous studies, the proposed method can characterize the viscoelastic and viscoplastic performance of different asphalt mixtures with higher efficiency and accuracy. Asphalt mixtures with dense-graded (AC-13) and gap-graded (SMA-13) aggregate structures were reconstructed by the three-dimensional locally homogeneous models. Laboratory experiments were conducted to identify the viscoelastic and viscoplastic parameters of the asphalt mortar matrix. The stress-strain responses of the developed locally homogeneous models were simulated based on the User-material (UMAT) programming in ABAQUS finite element software. The results provided comprehensive information on the different viscoplastic behavior of the dense- and gap-graded mixtures, which proves the capabilities of the proposed method. Besides, the proposed study can provide necessary references in future pavement analyses and constructions. • A viscoelastic-viscoplastic homogenization method is proposed. • Locally homogeneous models of AC-13 mixture and SMA-13 mixture are developed. • Viscoplastic coefficients of asphalt mortar are identified by laboratory tests. • The viscoplastic behaviours of AC-13 mixture and SMA-13 mixture are simulated. [ABSTRACT FROM AUTHOR]

Eichhornia crassipes is a hyperaccumulator of metals and has been widely used to remove metal pollutants from water, but disposal of contaminated plants is problematic. Biochar prepared from plants is commonly used to remediate soils and sequester carbon. Here, the catalytic activity of biochar prepared from plants enriched with iron was investigated as a potentially beneficial use of metal-contaminated plants. In a 30-day hydroponic experiment, E. crassipes was exposed to different concentrations of Fe(III) (0, 4, 8, 16, 32 and 64 mg/L), and Fe-biochar (Fe-BC) was prepared by pyrolysis of the plant roots. The biochar was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), Brunauer–Emmett–Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS) and atomic absorption spectrometry (AAS). The original root morphology was visible and iron was present as γ-Fe 2 O 3 and Fe 3 O 4. The biochar enriched with Fe(III) at 8 mg/L (8-Fe-BC) had the smallest specific surface area (SSA, 13.54 m2/g) and the highest Fe content (27.9 mg/g). Fe-BC catalytic activity was tested in the electrocatalytic reduction of H 2 O 2 using cyclic voltammetry (CV). The largest reduction current (1.82 mA/cm2) was displayed by 8-Fe-BC, indicating the highest potential catalytic activity. We report here, for the first time, on the catalytic activity of biochar made from iron-enriched plants and demonstrate the potential for reusing metal-contaminated plants to produce a biochar catalyst. Unlabelled Image [ABSTRACT FROM AUTHOR]

Computer vision systems have attracted much attention in recent years for use in detecting surface defects on rails; however, accurate and efficient recognition of possible defects remains challenging due to the variations shown by defects and also noise. This paper proposes a coarse-to-fine model (CTFM) to identify defects at different scales. The model works on three scales from coarse to fine: subimage level, region level, and pixel level. At the subimage level, the background subtraction model exploits row consistency in the longitudinal direction, and strongly filters the defect-free range, leaving roughly identified subimages within which defects may exist. At the next level, the region extraction model, inspired by visual saliency models, locates definite defect regions using phase-only Fourier transforms. At the finest level, the pixel subtraction model uses pixel consistency to refine the shape of each defect. The proposed method is evaluated using Type-I and Type-II rail surface defect detection data sets and an actual rail line. The experimental results show that CTFM outperforms state-of-the-art methods according to both the pixel-level index and the defect-level index. [ABSTRACT FROM AUTHOR]

Coamorphous systems have gained success in stabilizing amorphous drugs and improving their solubility and dissolution. Here we proposed to confine a binary mixture of drug and coformer (CF) within nanopores to obtain a nanoconfined coamorphous (NCA) system. For proving feasibility of this proposal, a poorly water-soluble drug (ibuprofen) and a frequently used pharmaceutical CF (nicotinamide) were loaded into nanopores of mesoporous silica microspheres. The solid state of NCA system was characterized by differential scanning calorimetry, X-ray powder diffraction, infrared spectrum, and solid-state nuclear magnetic resonance. With large numbers of nanopores, mesoporous silica microspheres appear to be a feasible carrier to transform a cocrystal system into coamorphism by nanoscale confinement. Benefiting from both nanoscale confinement and CF, the NCA system of ibuprofen achieved synchronic increase in dissolution properties and physical stability. Consequently, the NCA strategy is effective in achieving coamorphous state and offers a promising alternative for formulating poorly water-soluble drugs. [ABSTRACT FROM AUTHOR]

Introduction: The water-level fluctuation in the Three Gorges Reservoir Region has changed dramatically as a result of the hydroelectric project for flood control and power generation. The riparian seasonal hydrological environment also has changed from summer flooding with winter drought to summer drought with winter flooding. The changes of riparian seed bank and vegetation were investigated to determine the effects of the seasonal flooding on the composition and spatial distribution of riparian soil seed bank and the similarity of seed bank to standing vegetation. Case description: We conducted intensive riparian soil sampling (525 samples) along altitude gradient in the Shanmu River, a tributary of the Yangzi River in the reservoir region of China. Seed bank density, species richness and composition of soil seed bank were examined using the seedling-emergence method. The seasonal hydrological conditions resulted in a decrease in species diversity and an increase in the distribution heterogeneity of the soil seed bank. The soil seed bank was composed of 48 species from 22 families and 40 genera. Most species were annual and perennial herbaceous Polygonaceae, Asteraceae, and Poaceae. Rumex dentatus was the predominant species accounting for 27.0 % of the total seeds. Diversity and composition of the seed bank changed along an altitude gradient and soil depth. Maximum species richness was found in the top soil layer at 165 m and 175 m above sea level. The mean overall seed density of the soil seed bank was 13,475.3 ind m. Density and the number of seeds increased initially and then decreased with increased altitude. Maximum seed density (22,500.2 ind m) was found at 165 m above sea level in the intermediately flooded riverbank, with the seed number accounting for 27.8 % of the total soil seed bank. Average seed density declined significantly with soil depth. The similarity of seed bank to standing vegetation was relatively high. Discussion and Evaluation: The environmental heterogeneity created by the wide range and seasonal flooding led to the changes in biodiversity and seed density along altitude gradient. The seasonal flooding also led to the increase in the similarity of seed bank to standing vegetation as their composition both degraded. Conclusions: The seasonal flooding due to the dam reshape the composition and spatial distribution of riparian soil seed bank and limit the vegetation to a grassland dominated by a few annuals and perennials in the Three Gorges Reservoir Region. [ABSTRACT FROM AUTHOR]

Erosion of particles in elbows mounted in series is a detriment in the course of natural gas transmission. The flow and erosion characteristics of π-shaped pipelines were investigated via coupling the computational fluid dynamics (CFD) and the discrete phase model (DPM) method. The effect of pipe orientation on particle erosion was mainly studied. Spiral and asymmetrical trajectories of particles were observed from the second elbow to the downstream straight pipe of the fourth elbow in the non-coplanar π-shaped pipelines. The integral erosion rate of the first elbow increased by 0.35%, and it grew by 72.49% and 87.48% in the second and fourth elbows in non-coplanar structures, respectively, while the integral erosion rate of the third elbow reduced by 32.94%. In the actual transportation of natural gas, it is necessary to make local thickening treatment of the second and fourth elbow of the non-coplanar π-shaped pipelines. [Display omitted] • A swirling effect was discovered in non-coplanar structures. • Spiral and asymmetrical particle trajectories were generated. • Integral erosion degree of fourth elbow increased by 87.48% due to swirling effect. • The erosion rate increased exponentially with the increase of velocity. [ABSTRACT FROM AUTHOR]

Buyang Huanwu Decoction (BYHWD) is a classic formula widely used for treating stroke-induced disability, the highest morbidity of neurological disorders in China. However, the mechanism of its neuroprotection has not been fully clarified. Previous reports indicated that BYHWD may promote growth and differentiation of neural precursor cells (NPCs). The present study focused on the effects of BYHWD on migration of NPCs in rats with middle cerebral artery occlusion (MCAO). Rats were treated with different doses of BYHWD (12 and 24 grams/kg) from day 1 to day 21 after model building. BYHWD could increase the survival rate and decrease neurological scores and infarct volume as compared with the vehicle-treated MCAO rats. Moreover, BYHWD treatment significantly increased 5-bromo-2-deoxyuridine (BrdU)-positive cells in the subventricular zone (SVZ), subgranular zone (SGZ), and corpus striatum (CS) of the infarct brain. Interestingly, BYHWD could markedly enhance BrdU+/doublecortin+ cells not only in the SVZ and SGZ but also in CS, by up-regulating the protein expression of migration activators, including stromal cell derived factor-1, CXC chemokine receptor 4, vascular endothelial growth factor, Reelin, and brain-derived neurotrophic factor in the ipsilateral infarct area after MCAO. In addition, BYHWD treatment was able to promote the neuronal differentiation, which was closely related to the migratory process of NPCs in MCAO rats. These findings offer evidence for the first time that BYHWD may exert its neuroprotective effects partially by promotion of NPCs migration to ischemic brain areas. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to explore a composite thermosensitive in situ gelling formulation using the distribution of solid lipid nanoparticles (SLNs) among poloxamer-based hydrogels as a potential carrier for novel ocular drug delivery. SLNs containing the model drug Resina Draconis were prepared using a melt-emulsion ultrasonication method. A central composite design (CCD) was adopted to screen the thermosensitive hydrogel (THG) formulation. After aqueous SLNs were dispersed into the THG matrices, the physicochemical properties of the SLNs were characterized before and after their incorporation into hydrogels. The in vitro corneal penetration experiment, ocular irritant test and transcorneal mechanism across the cornea have been previously described to predict the feasibility for the proposed ophthalmic application. Finally, the optimal THGs consisted of 27.8% (w/v) poloxamer 407 and 3.55% (w/v) poloxamer 188. The particle size of the SLNs remained within the colloidal range. In vitro corneal penetration studies revealed a nearly steady sustained drug release. The hen's egg test-chorioallantoic membrane (HET-CAM) test indicated that all of the tested polymer systems were non-irritant. Coumarin-6 labeled SLNs formulated into THGs displayed a more homogeneous fluorescence with a deeper penetration intensity into the cornea at various times. Taken together, these results suggest that the SLN-based THG system can be used as a potential vehicle for ocular application. [Copyright &y& Elsevier]

Based on strain-resistance effect, an ultra-high pressure sensor has been developed with the range of 0–500 MPa. It is mainly composed of the elastic element and sensitive element. This sensor’s range is determined by the elastic element’s structure and material. In order to endure the ultra-high pressure, the elastic element’s material is selected as spring steel, and its structures are analyzed and simulated. After that, the metal strain gauge as the sensitive element is packaged on the elastic element. Then the sensor is developed after some compensation processes are carried out. In the end, the sensor is calibrated. The results show that the sensor has good performance, such as the accuracy of 0.35%FS, which meets the requirements of aerospace, weapons and other fields. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Saposhnikovia divaricata (SD), called “Fangfeng” in China, is commonly used in clinical compound prescription for treatment of rheumatoid arthritis (RA), but its actions on RA have not been clarified. The present study aims to determine the anti-inflammatory activity of SD chromone extract (SCE), the major bioactive component of SD, on collagen-induced arthritis (CIA) rats, and elucidate its underlying mechanisms with regards to its molecular basis of action on human fibroblast-like synoviocytes derived from RA patients (HFLS-RA). Materials and methods: CIA model on rats was constructed by injection of bovine type II collagen. Rats were pre-treated with different dosages of SCE from 3 days before till 35 days after model building. The progression of CIA was evaluated by macroscopic scoring, X-ray observation and hematoxylin and eosin (HE) staining of paws. HFLS-RA were pre-treated with different concentrations of SCE prior to stimulation with 10ng/ml of tumor necrosis factor (TNF) α. By radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA), levels of interleukin (IL)-1β, IL-6, TNFα and prostaglandin E2 (PGE2) were quantified respectively. Nuclear factor (NF-κB) p65 expression and DNA-binding activity were tested by immunohistochemisty and electrophoretic mobility shift assay (EMSA) respectively. Phosphorylation of extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 MAPKs were examined by immunohistochemisty staining and western blot analysis. Results: Histological examination and radiological observation demonstrated that SCE significantly reduced the inflammatory responses in the joints of CIA rats. SCE inhibited the production of TNFα, IL-1β, and IL-6 in the joint tissues and sera. The level of PGE2 in sera was also decreased by SCE. Moreover, SCE treatment in vivo was able to reduce protein level of NF-κB, the transcriptional factor closely related to the inflammatory process, in articular synovium and cartilage of CIA rats. In addition, SCE inhibited p-ERK, p-JNK and p-p38 expression, which were considered to be involved in the phosphorylation of transcription factor NF-κB and the transcription of pro-inflammatory factors. Further, SCE inhibited NF-κB DNA binding activity and attenuated the phosphorylation of ERK, JNK and p38 MAPKs, in a concentration-dependent manner in cultured HFLS-RA. Conclusion: These results highlight the anti-arthritic potential of SCE, and provide further evidence of the involvement of the NF-κB and MARKs inhibition in the effects of SCE. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Saposhnikovia divaricata (SD), called “Fangfeng” in China, is commonly used in clinical compound prescription for treatment of rheumatoid arthritis (RA), but its actions on RA have not been clarified. The present study aims to determine the anti-inflammatory activity of SD chromone extract (SCE), the major bioactive component of SD, on collagen-induced arthritis (CIA) rats, and elucidate its underlying mechanisms with regards to its molecular basis of action on human fibroblast-like synoviocytes derived from RA patients (HFLS-RA). Materials and methods: CIA model on rats was constructed by injection of bovine type II collagen. Rats were pre-treated with different dosages of SCE from 3 days before till 35 days after model building. The progression of CIA was evaluated by macroscopic scoring, X-ray observation and hematoxylin and eosin (HE) staining of paws. HFLS-RA were pre-treated with different concentrations of SCE prior to stimulation with 10ng/ml of tumor necrosis factor (TNF) α. By radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA), levels of interleukin (IL)-1β, IL-6, TNFα and prostaglandin E2 (PGE2) were quantified respectively. Nuclear factor (NF-κB) p65 expression and DNA-binding activity were tested by immunohistochemisty and electrophoretic mobility shift assay (EMSA) respectively. Phosphorylation of extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 MAPKs were examined by immunohistochemisty staining and western blot analysis. Results: Histological examination and radiological observation demonstrated that SCE significantly reduced the inflammatory responses in the joints of CIA rats. SCE inhibited the production of TNFα, IL-1β, and IL-6 in the joint tissues and sera. The level of PGE2 in sera was also decreased by SCE. Moreover, SCE treatment in vivo was able to reduce protein level of NF-κB, the transcriptional factor closely related to the inflammatory process, in articular synovium and cartilage of CIA rats. In addition, SCE inhibited p-ERK, p-JNK and p-p38 expression, which were considered to be involved in the phosphorylation of transcription factor NF-κB and the transcription of pro-inflammatory factors. Further, SCE inhibited NF-κB DNA binding activity and attenuated the phosphorylation of ERK, JNK and p38 MAPKs, in a concentration-dependent manner in cultured HFLS-RA. Conclusion: These results highlight the anti-arthritic potential of SCE, and provide further evidence of the involvement of the NF-κB and MARKs inhibition in the effects of SCE. [Copyright &y& Elsevier]

Hydrogen can be prepared by oil sludge (OS) gasification with steam, which is of great significance for industrial hazardous waste treatment and resource conservation. The gasification performance was studied by a tube furnace reactor. The OS gasification was carried out at different temperatures (600, 700, 800 and 900 °C) and with different steam to OS ratio (SOS) (0.1:1, 0.3:1, 0.5:1). During the gasification process, hydrogen production first increased and then decreased, and hydrogen production was faster in 5–15 min. The yield of hydrogen of OS gasification reached the maximum when the SOS was 0.3:1 at 800 °C. The highest hydrogen yield per unit mass OS was 48.50 mL min−1 g−1. After gasification, the char yield was high, generally more than 50%. It was necessary to treat the char and incineration was an effective solution for low carbon fuels. Thus particle size distribution, incineration thermogravimetric analysis and heavy metal leaching concentrations analysis were carried out. The results showed that the average particle size of char ranged from 85 to 120 µm. The char incineration process could be divided into three stages: water evaporation, the precipitation and combustion of volatiles, and the combustion of fixed carbon and heavy components. After OS gasification at 800 °C, the leaching concentrations of typical heavy metals (As, Cr, Cu, Ni, Pb and Zn) were all up to the standard. Therefore, OS gasification combined with char incineration was an effective approach for the utilization of solid waste, which can recover hydrogen energy and reduce environmental risks. [Display omitted] • Gasification of oil sludge with steam atmosphere was comprehensively investigated. • The characteristics and distribution of gas production were studied. • The incineration characteristics of gasification residues were studied. • Gasification and incineration coupling could complete treatment of solid waste. [ABSTRACT FROM AUTHOR]