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Depolysaccharide residues of edible fungus Pleurotus eryngii (dePSR-Pe), a mushroom industry waste, have abundant cellulose. In this study, the cellulose nanocrystals of P. eryngii (PeCNs) were extracted by hydrochloric acid. Results showed that the length of PeCNs is 469 ± 76.41 nm with a high aspect ratio of 40-100 and needle morphology. The structural characterization revealed that PeCNs had good thermal stability (approach 300 °C) and high crystallinity (84.2 %). An O/W Pickering emulsion stabilized with PeCNs was prepared to inhibit lipid oxidation and improve the loading capacity of triterpenes of P. coco. Unimodal size distribution of emulsion droplets was obtained under an optimized aqueous-phase condition to form a metastable emulsion, regardless of varying oil-water volume ratio50/50. In vitro digestion study suggested that triterpenes-loaded Pickering emulsion had 1-3 times higher drug stability than bulk oil. These metastable Pickering emulsions call for fewer nanoparticles and provide a new strategy for the industry application of cellulose nanocrystals at less cost.

Purpose: The purpose of this study was to compare the changes in lower extremity muscle morphology and electromyography (EMG) signals during treadmill running (TR) and plastic track running (PR). Methods: A total of 10 healthy male runners aged 22.5±1.3 years, height: 175.5±4.5 cm; weight: 71.9±2.7 kg; BMI: 22.1±1.1 volunteered to participate in this study. Muscle morphology data were collected by a portable ultrasound scanner before and after running. Median frequency (MF), mean power frequency (MPF) and root mean square (RMS) were monitored during TR and PR. Results: The results indicated that muscle thickness and pennation angle have increased after running. The muscle thickness after PR showed significantly higher than TR in tested muscle except tibialis anterior (TA) and medial gastrocnemius (MG). In contrast, only the pennation angle of TA and lateral gastrocnemius (LG) after PR was significantly different from that after TR (P P = 0.002). The most significant difference in the change rate of muscle thickness was found at TA. In addition, TA and MG showed significantly higher change rate of the pennation angle after TR than that after PR. Both of MF and MPF showed a downward trend after TR and PR. It could discover that the MF and MPF of LG during TR showed a significantly lower than that during PR both in two phases (P =0.001, P P = 0.001, P = 0.015). Furthermore, MF of RF during TR showed significantly different from that during PR (P = 0.017). From the point of RMS, in the first five minutes, the RMS of medical quadriceps (MQ), lateral quadriceps (LQ), hamstring muscles (HM) and MG during TR was significantly higher than that of PR (P P Conclusions: The current study indicated that TR and PR would cause different effects to lower extremity muscle morphology. In addition, the EMG signals based on running surfaces are also unconformity. Compared with the plastic track, the treadmill will bring more stimulation to the lower extremity muscles. The preliminary findings provide further insights into the rationality of runners’ choice of the running surface.

Polished high-purity aluminium was irradiated by 500 keV helium ions to a fluence of 3 × 1016 ions/cm2 at 450 °C. Then a micro-tensile sample was prepared by focused ion beam. The evolution of nanobubbles in irradiated aluminium upon stressing was investigated by employing in-situ tensile testing in a transmission electron microscope. In the case of helium-ions irradiation, dense bubbles with similar sizes are formed in a certain depth region from the irradiated surface. Upon tensile stressing, it was found that bubbles disappeared in the crack tip, and bubble coalescence occurred along the crack-propagation direction, which both contributed to the decrease of bubble number, whereas bubble sizes as well as bubble number showed almost no changes in the region far away the crack tip. This was caused by the non-uniform stresses in the stress fields, in which bubble migration occurred under the stress gradients while bubble evolution was hardly caused in a much low stressed region. Moreover, bubble sizes increased on the grain boundary and bubbles close to the grain boundary gradually disappeared upon stressing. This can be explained by the migration of helium bubbles toward the grain boundary under the stress gradients near the grain boundary.

Chenghui Lin,1,* Bin Gao,2,* Xuemao Yan,2 Zixiong Lei,3 Kebing Chen,3 Yuquan Li,2 Qing Zeng,2 Zeqin Chen,2 Haomiao Li3 1Department of Medical oncology, TangXia Hospital of DongGuan, DongGuan, P.R. China; 2Department of Orthopedics, TangXia Hospital of DongGuan, DongGuan, P.R. China; 3Department of Musculoskeletal Oncology, The Third Affiliated Hospital of Southern Medical University, Guangzhou, P.R. China *These authors contributed equally to this work Purpose: The purpose of this study is to evaluate the effects of miR-628 on migration and invasion of breast cancer stem cells (CSCs), which are essential for tumor recurrence and metastasis. Materials and methods: Quantitative reverse transcription-polymerase chain reaction was used to determine the expression of microRNAs and mRNAs. A subpopulation of CD44+/CD24- breast CSCs were sorted by flow cytometry. Transwell assays were used to evaluate cell migration and invasion. Luciferase reporter assays were performed to verify whether miR-628 targeted SOS Ras/Rac guanine nucleotide exchange factor 1 (SOS1). pcDNA3.1(+)-SOS1 was constructed for overexpressing SOS1 after transfection. Results: Compared with primary breast cancer cells, bone metastatic breast cancer cells showed significant downregulation of miR-628. The CD44+/CD24- breast CSC subpopulations in MDA-MB-231 and MCF-7 cell lines were analyzed and sorted. Transfection with an miR-628 mimic significantly suppressed the migration and invasion of these breast CSCs by targeting SOS1, which plays an essential role in epithelial-to-mesenchymal transition. Overexpression of SOS1 rescued miR-628-mediated migration and invasion by upregulating Snail and vimentin, and downregulating E-cadherin. Conclusion: miR-628 suppressed migration and invasion of breast CSCs of MDA-MB-231 and MCF-7 cells by directly targeting SOS1. Enhancement of miR-628 expression might be an effective strategy for managing breast cancer metastasis. Keywords: breast cancer stem cells, CD44+/CD24-, miR-628, SOS1, migration, invasion

The root architecture parameters are important to the study of plant growth state and the segmentation of plant roots is the key to the measurement of these parameters. Most existing methods use the threshold calculated by different algorithms to segment the roots in a grayscale image, which requires a low noise background. We designed a set of automatic equipment to record the roots images of rice seedlings planted in transparent bags. Those root images contain strong noise and it makes existing methods invalid in our circumstances. To solve the segmentation problem of rice roots under strong noise, we proposed a convolutional neural network based on U-Net and SE-ResNet. The root images were preprocessed and cropped into small patches to fit CNN input requirements. Experiments have shown that our method performs effectively in pixel-level segmentation of rice seedling roots that contain tiny lateral roots. Our method achieves an intersection over union (IoU) of 87.4%. This method provides a new approach to automatic and fast pixel-level root segmentation, which is of great importance for the analysis of root morphology.

The use of soft normally open point (SNOP) instead of the traditional tie switch can realize the closed-loop operation of the urban distribution network and realize the controllability of the transmission power of the feeder. In this paper, for the 10kV AC feeders of the urban distribution network, the SNOP composed of the back to back voltage source converter (B2B-VSC) is used to flexibly interconnect the two feeders, then, based on the droop control, an active power real-time modulation strategy based on power equalization technology is designed. The active power distribution coefficient is used to realize the active power deviation control of the feeders, and the load balance between the feeders is realized. The PSCAD/EMTDC simulation software was used to build a two-feeder distribution system using SNOP flexible interconnection, and the original dual-loop control strategy was improved by using power balance technology. The simulation results show that the active power real-time modulation strategy based on power equalization technology can balance the load between feeders in real-time under the condition of local control, and improve the utilization and operational reliability of feeder equipment.

In this study, antibiotic resistance to macrolide-lincosamide-streptogramin B (MLSB) antibiotics in total microbial community in surface water in a coastal urban city was measured using a modified fluorescence in situ hybridization (FISH) technique. This FISH technique quantified the rate of antibiotic resistance to MLSB antibiotics through targeting methylation site of A2058 of 23S rRNAs resulting from expressed erythromycin ribosome methylation (erm) genes. Correlations between the rates of MLSB resistance measured by FISH and macrolide concentrations was stronger than that between the relative abundance of erm genes and macrolide concentrations, especially in residential areas where the main detected antibiotics were macrolides. These results suggest that trace levels of antibiotics in environmental waters, which was as low as 40 ng L−1, may still play important roles in the development and spread of antibiotic resistance. Additionally, methylation as a result of erm gene expression, instead of erm gene abundance, was a better indicator of selective pressure of trace level macrolides. The rates of MLSB resistance varied significantly among land use types, suggesting that anthropogenic activities are important factors to select for erm gene expression in the environment. Microbial community analysis of representative surface water samples showed that relatively high rates of MLSB resistance were observed in Alphaproteobacteria (42%), Acidobacteria (36%), Bacteroidaceae (32%), Chloroflexi (27%), and Betaproteobacteria (20.2%).

Antibiotics in surface waters and soils are growing public health concerns and treated wastewater has often been identified as the main source of antibiotics. However, few studies have been conducted to evaluate the occurrence and concentrations of antibiotics in coastal cities without direct impact of wastewater discharge. In this study, the occurrence of 14 antibiotics including four macrolides, three sulfonamides, three β-lactams, lincomycin, chloramphenicol, furazolidon, and monensin in surface waters and soils in Singapore were analyzed with SPE-LC-ESI-MS/MS. The detected concentrations of antibiotics were all below 82.5 ng/L in surface waters and below 80.6 ng/g dry wt in soils. These concentrations were significantly lower than other cities that were under the impact of treated wastewater discharge, suggesting that reduction of treated wastewater discharge reduces occurrence of antibiotics in the environment. However, the wide occurrence of trace levels of antibiotics suggest that other factors may have contributed to detected environmental antibiotics. Population density was positively correlated with concentrations of clarithromycin, lincomycin, azithromycin, and sulfamethoxazole in surface waters, suggesting that non-point source pollution due to anthropogenic pressure may contribute to the wide detection of trace levels of antibiotics. The potential impact of antibiotic use, natural production, and half-lives of antibiotics were further discussed. Further studies are needed to evaluate how anthropogenic activities other than wastewater discharge may contribute to the occurrence of trace level antibiotics and their associated health risks in urban environments.

Flexible distribution network, which can accept distributed power, is a key feature of smart distribution network in the future. Firstly, the basic structure of distribution system with soft open point (SOP) is established in this paper. PV, fan and energy storage are connected to the AC or DC area of distribution network according to the characteristics of each distributed power. Then, this paper do researches on the mathematical model of SOP and its main operational control strategy. Finally, in this paper, the simulation experiments of feeder output optimal equalization, uninterruptible power supply and energy scheduler for flexible distribution network are carried out by the flexible switching of control mode and operational strategy of converter. The result of simulation verifies that the system structure of AC and DC flexible distribution network with SOP has the advantages of receiving distributed power and flexible control.

When the major failure of power grid happened, the network voltage dropped and the line currentincreased rapidly, which caused the rotor current of DFIG improved and the DC bus voltage increased that threatened the safety of power electronic device. Some measures are proposed to help DFIG ride through low voltage fault. Aiming at voltage drop sharply, the crowbar protection circuit is used widely in wind power plant. In this paper, the crowbar protection circuit is studied and the value of crowbar resistance is calculated. The simulation results show that DFIG have the best low voltage ride through (LVRT) ability with the optimum value of crowbar resistance.

This paper reports an optimized end-bonding magnetoelectric (ME) heterostructure FeCuNbSiB-PZT-FeCuNbSiB (FPF) for sensitive magnetic field sensor. The heterostructure is made by attaching magnetostrictive Fe73.5Cu1Nb3Si13.5B9 (FeCuNbSiB) foils at the free ends of piezoelectric Pb(Zr1-x,Tix)O3 (PZT) plates. Due to the structural advantages, the FPF has ∼3.12 times larger resonance voltage coefficient (αME,r) than traditional FeCuNbSiB/PZT laminate. And compared with the Metglas-PZT-Metglas heterostructure, the FPF heterostructure has stronger ME responses for the excellent magnetic characteristics of FeCuNbSiB. In experiments, the FPF heterostructure is optimal designed through adjusting the thickness of PZT plate (tp) and the length of FeCuNbSiB foil (L). The results demonstrate that the maximum αME,r of 662.1 (V/cm Oe) is observed at 13 Oe DC bias magnetic field when L = 15 mm and tp = 0.6 mm. Based on the giant ME coupling, the DC magnetic field sensitivity for the optimized FPF heterostructure is 3.89 nT at resonant frequency. These results are very promising for the cheap room-temperature magnetic field sensing technology.

This paper develops a self-biased magnetoelectric (ME) heterostructure FeCuNbSiB/Ni-PZT-FeCuNbSiB/Ni (FN-P-FN) by bonding magnetization-graded FeCuNbSiB/Ni layers at the free ends of piezoelectric Pb(Zr,Ti)O3 (PZT) plate. By using the magnetization-graded magnetostrictive layer and end-bonding heterostructure, giant self-biased ME responses and obvious hysteresis are observed in FN-P-FN heterostructure. The experimental results show that the zero-biased ME voltage coefficient of FN-P-FN heterostructure reaches ∼183.2 (V/cm Oe), which is ∼2.1, ∼4.5, and ∼41.6 times higher than that of FeCuNbSiB/Ni/PZT, Ni-PZT-Ni, and FeCuNbSiB-PZT-FeCuNbSiB composites, respectively. The results indicate that the proposed three-phase end-bonding heterostructure shows promising applications for high-sensitivity self-biased magnetic field sensors and ME transducers.