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Many studies have been undertaken to predict local scour around offshore high-rise structure foundations (HRSFs), which have been used in constructing the Donghai Wind Farm in China. However, there have been few works on the turbulent flow that drives the scour process. In this study, the characteristics of the turbulent flow fields around an HRSF were investigated using the particle image velocimetry technique. The mean flow, vorticity, and turbulence intensity were analyzed in detail. The relationship between the flow feature and scour development around an HRSF was elaborated. The results showed that the flow velocity increased to its maximum value near the third row of the pile group. The shear layer and wake vortices could not be fully developed downstream of the last row of the piles at small Reynolds numbers. The strong flow and turbulent fluctuation near the third piles explained the existence of a long-tail scour pattern starting from the HRSF shoulders and a trapezoidal deposition region directly downstream of HRSF. This laboratory experiment gains insight into the mechanism of the turbulent flow around HRSFs and provides a rare dataset for numerical model verifications.

Ten ingenane-type diterpenoids, including two undescribed compounds named as kansuininols A–B (1–2), were isolated from the roots of Euphorbia kansui. Their structures were elucidated by detailed interpretation of their spectroscopic data, especially 2D-NMR and HR-ESI-MS. Chemoreversal assays of these isolates were carried on adriamycin resistant human breast adenocarcinoma cell line MCF-7/ADR, and compounds 1–2 were identified as potent low-cytotoxic MDR modulators with greater chemoreversal ability than the positive drug verapamilti.

Strontium (Sr) ions were added to porous magnesium (Mg) oxide with silicon and fluorine by microarc oxidation (MAO) to improve its osteogenic and pro-angiogenic properties. First, pure Mg was oxidized by MAO, and Sr was added by electrolysis. The surface of the resulting Sr coating was characterized by SEM, EDS, and EDS mapping. The release of Sr ions was monitored by ICP-OES. The antibacterial property of the coating was assessed against Staphylococcus aureus. The effect of Sr coating on osteogenesis was tested in MC3T3-E1 cell line by performing cell adhesion and proliferation tests, alkaline phosphatase (ALP) activity detection, cell morphology characterization, alizarin red staining, and osteogenic-related gene expression analysis. Finally, HUVECs cells were used to test the effect of Sr coating on angiogenesis through cell migration and tube formation assays, VEGF quantification, chicken embryo chorioallantoic membranes (CAM) test, and angiogenic-related gene expression analysis. The results showed that Sr coating had a hierarchical microstructure with a microporous structure evenly covered with nano-grains and that the Sr elements from the coating were released slowly and continuously. Sr coating had effective antibacterial properties and promoted cell adhesion, proliferation, ALP release, calcium nodule formation, and upregulated osteogenic gene expression. Moreover, the coating could promote migration, tube formation, VEGF expression, and angiogenic gene upregulation in endothelial cells. Sr coating also enhanced angiogenesis of CAM. This study supports that Sr coating on Mg- MAO enhances osteogenesis and angiogenesis.

Polymer composites filled with conductive particles for high dielectric constant (high-κ) have been extensively studied due to their distinct advantages such as good processability, flexibility and lightweight. However, to achieve high dielectric constant usually requires high loadings of filler, which may bring conductivity leading to large dielectric loss. Here, insulative CaCO3 is uniformly coated on the surfaces of carbon nanofibers (CNFs) via a facile self-assembly route, resulting in a core-shell structured CaCO3@CNF. Blending it with epoxy resin shows an obvious enhancement in dielectric constant to neat epoxy resin due to the presence of 2.1 wt% CNFs in composite. Importantly, uniform dispersion of the core-shell structure with about 80 nm insulating shell can effectively block electron current. Then reduced dielectric loss and enhanced dielectric constant could occur simultaneously, which is significantly positive to the composites for further electric energy storage.

Optical flow is widely used in medical image processing, such as image registration, segmentation, 3D reconstruction, and temporal super-resolution. However, high-precision optical flow training datasets for medical images are challenging to produce. The current optical flow estimation models trained on these non-medical datasets, such as KITTI, Sintel, and FlyingChairs are unsuitable for medical images. In this work, we propose a semi-supervised learning mechanism to estimate the optical flow of coronary angiography. Our proposed method only needs the original medical images, segmentation results of regions of interest, and pre-trained models based on other optical flow datasets to train a new optical flow estimation model suitable for medical images. First, we use the coronary segmentation results to perform image enhancement processing on the coronary vascular region to improve the image contrast between the vascular region and the surrounding tissues. Then, we extract the high-precision optical flow of coronary arteries based on the coronary-enhanced images and the pre-trained optical flow estimation model. After estimating the optical flow, we take it and its corresponding original coronary angiography images as the training dataset to train the optical flow estimation network. Furthermore, we generate a large-scale synthetic Flying-artery dataset based on coronary artery segmentation results and original coronary angiography images, which is used to improve and evaluate the accuracy of optical flow estimation for coronary angiography. The experimental results on the coronary angiography datasets demonstrate that our proposed method can significantly improve the optical flow estimation accuracy of coronary angiography sequences compared with other methods.

Designing versatile materials for radiation protection is of great significance to the rapid development of nuclear technology. Here, BN@PbWO4 core-shell particles are successfully prepared via a facile sol-gel method. The structure and morphology of products are determined by XRD, SEM, TEM and FTIR techniques. Compared with PbWO4 and h-BN, BN@PbWO4 exhibits much more excellent photocatalytic ability to degrade the organic dye Rhodamine B (RhB). Furthermore, it also has a good ability to jointly shield neutron and gamma radiations, especially better gamma radiation shielding in comparison with PbWO4. This work provides an integrated solution with the material that could deal with organic wastes and shield complex radiations in nuclear industry.

This is the first phytochemical investigation of Schisandra tomentella A. C. Smith. 11 lignans and 8 sesquiterpenoids, were isolated from the stems of S. tomentella, including two undescribed lignans, tomentaschinins A-B (1-2), and two new sesquiterpenoids, tomentaschinnes A-B (3-4). Their structures were elucidated based on the interpretation of their spectroscopic data. Cytotoxicity and MDR reversal effect of these compounds were screened on multidrug resistance cancer cell line MCF-7/ADR, and results showed gomisin M

The linear and nonlinear dynamic responses of a vibratory ring gyroscope are investigated in this study focusing on the response mechanism of such a vibratory gyroscope. It is found that the nonlinear equations governing the drive and sense directions are coupled through both inertial linear and geometric nonlinear terms. Nonlinear responses are studied based on the full coupled nonlinear dynamic equations. The varying amplitude on the sense direction is analyzed for different input angular rates. The effect of nonlinearity on the ring gyroscope system is performed by comparing the results of nonlinear responses to those of linear responses. The contributions of some parameters to the amplitude responses and gyroscope sensitivity are analyzed, the conclusions of which provide guidelines to improve the sensitivity of the vibratory ring gyroscopes. Keywords: Vibratory ring gyroscope, Amplitude responses, Nonlinear effect, Sensitivity

This paper proposed a fluidic tunable lens with polymer membrane and multi-flow structure. The designed lens mainly consists of five optical layers including one polymer membrane, two solid layers and two liquid layers. A series of slime hexagonal holes are drilled in the solid layers and the lens holders, allowing the optical liquid flowing among the different layers. The integrated structure of the fluidic lens was presented, as well as the lens composition and fabrication process. The deformation process of the fluidic lens are measured and analyzed, and the optical property are simulated using Zemax software. Images captured through a prototype lens at various rotating angles presents almost identical patterns and the same image quality, showing good stability to gravity. The lens focal length can be adjusted flexibly from 32.3 mm to 14.3 mm under a tiny injection volume of 86.4 uL. Numerical analyses show that the lens distortion is less than 3% and relative illumination is above 0.72. The fluidic tunable lens shows the potential to be used in various compact, low cost and stable optical systems.

Membrane scaling is a critical challenge for membrane distillation (MD), especially when treating hypersaline brines. In this study, an anti-scaling membrane was developed with a liquid-like surface coating. This fabrication approach combined electrospun polyvinylidene fluoride (PVDF) membrane with surface fluorination without the addition of nanoparticles. Two fluoro silanes with the same alkyl-chain length but different hydrolysis reaction sites were investigated as the fluorination agents. Membrane characterizations indicated that surface modification with the single hydrolysis site fluoro silane (17-FAS-S) did not change the membrane morphology or structure. On the other hand, surface modification with the triple hydrolysis site fluoro silane (17-FAS-T) generated nanoparticles on the membrane surface, resulting in increased roughness. While both the 17-FAS-S and 17-FAS-T modified membranes exhibited excellent scaling resistance in the MD scaling tests, the 17-FAS-S membrane provided a much higher vapor flux than the 17-FAS-T one. Finally, the mechanism of scaling resistance and vapor permeability provided by the liquid-like modification was discussed.

Semiconductor-based magnetoresistance (MR) device has many advantages such as high MR ratio at low switching magnetic field, but electron spins were ignored completely in previous researches. Electron spins should impact on performance of semiconductor-based MR device, as electron spins interact with magnetic fields. By considering a semiconductor microstructure constructed on GaAs/AlxGa1-xAs heterostructure by patterning two asymmetric ferromagnetic (FM) stripes, we theoretically explore effect of electron spins on semiconductor-based MR device. An interesting spin splitting effect is found in semiconductor-based MR device. Both magnitude and sign of spin splitting effect can be modified by applying a negative voltage. These findings may be helpful for designing semiconductor-based MR devices.

A practical synthetic method has been developed for polyfunctionalized biaryls based on a facile one-pot nucleophilic aromatic substitution (SNAr) reaction and [5,5]- or [3,3]-sigmatropic rearrangement reaction cascade. Under mild basic conditions, N-arylhydroxylamines reacted with o-activated fluoro (het)arenes to form N,O-diarylhydroxylamine intermediates which underwent spontaneously selective [5,5]-sigmatropic rearrangement reaction to produce diverse functionalized 4-amino-4′-hydroxy-1,1′-biaryls. A sequential SNAr reaction and [3,3]-sigmatropic rearrangement took place between N-arylhydroxylamines and 2-fluoropyridine derivatives or 4-fluorobenzonitrile to afford functionalized 2-amino-2′-hydroxy-1,1′-biaryls. As invaluable and unique building blocks, the resulting biaryls were applied in the straightforward synthesis of N2,O2-coronarene, carbazole, aza- and diaza carbazole derivatives.

Harmful algal blooms (HABs) could be deemed hazardous materials in aquatic environments. In this study, we investigated aerobic denitrification and algicidal effects of the Raoultella sp. R11. Based on PCR amplification, the denitrification genes nap A was detected. A response surface methodology (RSM) analysis demonstrated that the maximum nitrate removal ratio was 96.06%, and optimal conditions occurred for inoculum of 13.02% (v/v), initial pH of 6.65, C/N ratio of 7.59 and temperature of 27.08 °C based on a ridge analysis. When the Microcystis aeruginosa flour as carbon and nitrogen source for denitrification in aerobic conditions, the NO 3 − -N and TOC removal ratios were 72.36% and 85.56%, respectively. Additionly, the denitrification rate was 0.0123 mg L −1 h −1 . Furthermore, the infrared spectrogram and SEM images showed the M. aeruginosa cell structure was destroyed, indicating that R11 could use algal death for denitrification. Therefore, Raoultella sp. R11 played a crucial role for simultaneous denitrification and algicidal effects in wastewater treatment.

The gravitational sag of aspheric bent mirrors with face-up or face-down geometry produces a nonnegligible optical error. As an effective compensation, width optimization is used to match the combined effects of the gravitational and bending moments. This method is described by analytical expressions and two calculation algorithms. The results of theoretical simulations and finite element analysis have proved that this method can reduce the slope error resulting from gravitational sag to the level of nano radians.

Background Sepsis causes nutritional substrate malabsorption; hence, preventing gut barrier problems and improving the nutritional status in sepsis is a compelling issue. Aims We tested whether ghrelin administration affects peptide transporter 1 (PepT1) activity in the intestinal epithelium of rats with sepsis. Methods Sixty male Sprague-Dawley rats were randomly divided into sham-operated, sepsis, and ghrelin-treated groups. The cecum of sham-operated rats was separated after laparotomy without ligation and perforation. Sepsis group rats underwent cecal ligation and puncture (CLP). Mucosal specimens were used for immunohistochemstry, real-time PCR, and western blotting to detect PepT1 distribution, and mRNA and protein expression levels, respectively. TNF-α, IL-1β, and ghrelin levels were estimated in serum and intestinal mucosal tissue by ELISA. High-performance liquid chromatography was used to measure PepT1 uptake by the epithelial cells. Moreover, survival, body weight, and food intake of the rats were recorded during the 7-day treatment period. Results All rats in the sham-operated group survived, and 80% of rats in the sepsis group died within 7d of CLP. Treatment with ghrelin attenuated the CLP-induced body weight loss, intestine mucosa damage, and the survival rate was better. In addition, ghrelin attenuated increases in TNF-α and IL-1β production. The expressions of PepT1 mRNA and protein were higher in ghrelin-treated group rats than in sepsis rats. Moreover, the uptake function of PepT1 was better in ghrelin-treated group rats. Conclusion Ghrelin treatment can reduce the inflammatory response and greatly upregulate the physiological function of PepT1 in intestinal epithelial cells of rats with sepsis.

Little information is available regarding the kinetics, products, and pathways of simultaneous SMX degradation and Cd(II) immobilization from wastewater. In this study, a novel bacterium (Achromobacter sp. L3) with SMX degradation and Cd(II) immobilization capabilities was isolated. The boundary conditions of SMX degradation were as follows: initial pH 6-8, temperature 25-30 °C, and SMX concentration 10-40 mg/L-1. The boundary conditions of Cd(II) immobilization were as follows: initial pH 7-9, temperature 25-35 °C, and SMX concentration 10-30 mg/L-1. The maximum SMX degradation and Cd(II) removal were 91.98% and 100%, respectively. The SMX degradation and Cd(II) immobilization data fitted well with the pseudo-first-order kinetic model, indicating that the two pollutants conform to the same degradation rule. Moreover, the microbial degradation, sediment adsorption, and intermediates identified in the experiments were used to explore the mechanisms of SMX and Cd(II) removal. These results indicate that microbial removal and sediment adsorption play equally important roles in Cd(II) immobilization; however, microbial degradation plays a decisive role in SMX degradation. Furthermore, the relationship between aerobic denitrification, SMX degradation, and Cd(II) immobilization was proposed. These results may provide valuable insights for treatment of wastewater polluted by antibiotics and heavy metals.

This study investigated whether bioaugmentation improves sulfamethoxazole (SMX) degradation and nitrogen removal in the Moving Bed Biofilm Reactor (MBBR) system. The effects of the C/N ratio on SMX degradation and nitrogen removal were also evaluated. Using MBBR system operation experiments, the bioaugmented reactor was found to perform more effectively than the non-bioaugmentation reactor, with the highest SMX, nitrate-N, and ammonia-N removal efficiencies of 80.49, 94.70, and 96.09%, respectively. The changes in the sulfonamide resistance genes and bacterial communities were detected at various operating conditions. The results indicate that the diversity of the bacterial communities and the abundance of resistance genes were markedly influenced by bioaugmentation and the C/N ratio, with Achromobacter among the dominant genera in the MBBR system. The bio-toxicity of samples, calculated as the inhibition percentage (IP) toward Escherichia coli, was found to decrease to non-toxic ranges after treatment.

The pharmaceutical industry produces large volumes of low C/N ratio wastewater that is difficult to treat. In this study, we isolated Achromobacter sp. JL9 with high efficiency for sulfamethoxazole degradation and nitrogen conversion in low C/N ratio pharmaceutical wastewater. The SMX biodegradation and nitrogen removal ratio were 92.4% (nitrate-N), 86.7% (ammonia-N), 89.4% (total nitrogen), and 90.4% (SMX). The reaction kinetics and reaction rate constant were C/N ratio-, SMX concentration-, and dissolved oxygen concentration-dependent, and the highest reaction rate constant for SMX biodegradation was 0.0384 min−1. Gaseous compounds analysis and Nap gene amplification analysis by gas chromatography (GC) and polymerase chain reaction (PCR), respectively, showed N2 as an end product during nitrogen conversion. Moreover, toxicity assays were conducted by the inhibition percentage (PI) and agar well diffusion methods. The toxicity of the medium gradually decreased, falling within the nontoxic range after 96 h. The present study showed that biological technologies could be an effective, economical, and environmentally friendly remediation against pharmaceutical pollutants.

A magnetoresistance device was proposed by patterning two asymmetric ferromagnetic stripes on top and bottom of the GaAs/AlxGa1-xAs heterostructure. To control its performance, a tunable δ-potential is introduced inside this device by wire-like doping. Adopting transfer matrix method and Landauer-Buttiker conductance theory, Schrodinger equation is solved analytically and δ-doping dependent transmission, conductance and magnetoresistance ratio are calculated. An obvious magnetoresistance effect still stays in this device, due to existence of transmission difference between parallel and antiparallel configurations independent of δ-doping. However, its magnetoresistance ratio can be tuned by changing weight or position of δ-doping. These interesting results not only propose an alternative scheme to manipulate magnetoresistance device, but also a structurally-controllable magnetoresistance device can be obtained for magnetic information storage.

Lanostane-type triterpenoids, inotolactones A and B, a drimane-type sesquiterpenoid, inotolactone C, and five known terpenoids 6β-hydroxy-trans-dihydroconfertifolin, inotodiol, 3β,22-dihydroxyanosta-7,9(11),24-triene, 3β-hydroxycinnamolide, and 17-hydroxy-ent-atisan-19-oic acid, were isolated from the submerged culture of chaga mushroom, Inonotus obliquus. Their structures were characterized by spectroscopic methods, including MS and NMR (1D and 2D) spectroscopic techniques. Inotolactones A and B, examples of lanostane-type triterpenoids bearing α,β-dimethyl, α,β-unsaturated δ-lactone side chains, exhibited more potent alpha-glucosidase inhibitory activities than the positive control acarbose. This finding might be related to the anti-hyperglycemic properties of the fungus and to its popular role as a diabetes treatment. In addition, a drimane-type sesquiterpenoid and an atisane-type diterpenoid were isolated from I. obliquus.

A novel optical Rhodamine-Furan type chemosensor (RF) was easily synthesized and characterized as a revisable switch. It dispalyed high selectivity toward Al 3+ among 19 metal ions and the resultant complex [RF–Al 3+ ] as a sequential chemosensor toward F − among 16 anions in neutral aqueous media (ethanol/water, v/v = 2/3, Tris–HNO 3 , 10 mM, pH 7.0). Moreover, detecting fluoride at concentration below the maximum contaminant level in drinking water defined by the U.S. Environmental Protection Agency (4.0 mg L −1 , 211 μM) could be achieved with a detection limit (LOD) estimated down to 1.6 μM. Both sensors were very easily to construct and only required simple synthesis. The reversible ring-open mechanism of the rhodamine spirolactam induced by Al 3+ binding and the 1:1 stoichiometric structure between RF and Al 3+ were adequately supported by job plot evaluation, optical titration, and 1 H NMR study. Finally, it could be conveniently used for the determination of fluorides in dental products such as toothpastes with “naked eye” due to the obvious color change of testing solution, showing its potentially practical application.