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Yam mucilage is a novel environmentally friendly drag reducer. This study investigates drag reduction and degradation characteristics of Chinese yam mucilage, using an in-house rotor device. The effects of temperature, aging, and salts on the drag reduction rate (DR) of yam mucilage were also explored. Furthermore, the synergistic drag reduction properties of Chinese yam-polyethylene oxide (PEO) solution were investigated by blending Chinese yam mucilage with PEO. The rotational speed range of the rotor device was set at 200–700 r/min, corresponding to Reynolds numbers (Re) ranging from 30 396 to 106 385. The results demonstrated that the DR of yam mucilage initially increased, and then decreased at low concentrations, with increasing Re. Conversely, the DR of yam mucilage at high concentrations increased with increasing Re, albeit at a gradually slowing rate as concentration increased; however, the shear stability was gradually enhanced. Degradation testing revealed that yam slime exhibited semi-rigid, or rigid polymer characteristics, with notable shear stability. At a concentration of 2000 ppm and Re = 106 385, the maximum DR reached 44.1%. Prolonged heating and standing resulted in the reduced DR of yam mucilage. However, salt ions exerted dual effects on the DR of yam mucilage: Low concentrations of NaCl improved its effectiveness while Na2SO4 and high concentrations of NaCl diminished its efficacy. The addition of a small quantity of PEO was found to significantly enhance the drag reduction efficacy of yam mucilage, but no significant improvement in the shear stability of yam mucilage was observed. Yam mucilage exhibits promising potential as an environmentally friendly drag reducer with remarkable drag reduction capabilities. [ABSTRACT FROM AUTHOR]

Nontoxic bio-polymeric drag reducers are of great practical importance. In this work, a new natural and environmentally friendly drag reducer is introduced, which is extracted from the yam. Yam mucilage solutions are highly shear thinning and are insensitive to temperature variation. Their drag-reducing capability is tested in a water tunnel with the injection of yam mucilage solutions at the bottom wall. The main flow speed varies 0.5–2 m/s, and the corresponding bulk Reynolds number (Re) varied from 11 467 to 45 868. The mean concentration profile from the planar laser-induced fluorescence (PLIF) images and the mean velocity profile from the particle image velocimetry (PIV) images are obtained to explain the drag reduction of the yam mucilage solution. A maximum drag-reduction rate (DR) of 25.27% is achieved. The effects of the solution concentration, the injection rate, and the main flow speed on the drag-reduction efficiency are explored. The DR-log10K fitting curve is linear, consistent with that of the reported polymer drag reducers. The K-scaling laws also imply that the consumption of yam mucilage would be much more than that of polyethylene oxide (PEO) corresponding to similar DR. The further revelation of the effective drag-reducing component within the yam mucilage is believed to promote the efficiency of drag reduction. The yam mucilage is a candidate drag-reducing agent that can be an alternative to existing polymer solutions. [ABSTRACT FROM AUTHOR]

Optical chaos has attracted widespread attention owing to its complex dynamic behaviors. However, the time delay signature (TDS) caused by the external cavity mode reduces the complexity of optical chaos. We propose and numerically demonstrate the critical dispersion of chirped fiber Bragg grating (CFBG) for eliminating the TDS of laser chaos in this work. The critical dispersion, as a function of relaxation frequency and bandwidth of the optical spectrum, is found through extensive dynamics simulations. It is shown that the TDS can be eliminated when the dispersion of CFBG is above this critical dispersion. In addition, the influence of dispersive feedback light and output light from a laser is investigated. These results provide important quantitative guidance for designing chaotic semiconductor lasers without TDS. [ABSTRACT FROM AUTHOR]

HLA‐A*02:1146 differs from HLA‐A*02:01:01:01 by one nucleotide in exon 1. [ABSTRACT FROM AUTHOR]

The secondary effluent of the sewage treatment plant was treated by sodium hypochlorite oxidation combined with powdered activated carbon and ultrafiltration process (NaClO-PAC-UF). The effects of the dosage of NaClO, pH and temperature on the removal of antibiotic resistance genes (ARGs) and dissolved organic carbon (DOC) in the secondary effluent were investigated. The results show that 8.0 mg/L effective chlorine concentration of sodium hypochlorite oxidizing agent was the best removal effect. The removal amount of different types of ARGs (tetA, tetC, tetG, sulI, sulII) in secondary effluent was 103.25 ~ 103.47 copies/mL. The removal effect of cellular and free ARGs was significantly enhanced. The removal rate of DOC by the combined process was up to 57.5 %, and the removal rate of organic matter with different molecular weight was improved overall. Increasing temperature and decreasing pH can improve the removal effect of ARGs by the combined process. [ABSTRACT FROM AUTHOR]

Reservoir is regarded as one of the most important engineering measures in promoting the high-efficiency utilization of the limited water resources, like water supply, peak operation, power generation and environment protection. Accurate discharge data simulation and prediction information is an essential factor to achieve the expected goals. With the booming development of computer technologies, machine learning is becoming increasingly popular in water resource field. As a classical machine learning approach, adaptive neuro-fuzzy inference system (ANFIS) may fail to effectively capture the nonstationary features of discharge time series in practice. In order to alleviate this problem, this paper develops a hybrid discharge time series simulation method, where the emerging cooperative search algorithm (CSA) is used to find the satisfying parameter combinations of the ANFIS model for the first time. To prove its feasibility and effectiveness, the proposed method is used to simulate multiple-time-scale discharge data of a huge reservoir in China. Based on several statistical indicators, the experiment results indicate that the developed method yields better simulation results than the conventional ANFIS model. Thus, the utilization of swarm intelligence tools can effectively improve the performances of machine learning models in simulating discharge data under hydropower reservoir operation. [ABSTRACT FROM AUTHOR]

More than half of the patients with acute myeloid leukemia (AML) fail to achieve long-term disease-free survival with current therapies and novel therapeutic strategies are urgently needed. The effects of homoharringtonine (HHT) on the growth of AML cell lines and primary leukemia cells were examined using MTT, colony formation assay. The effects of HHT on both eukaryotic translation initiation factor 4E (eIF4E) and phospho-eIF4E(p-eIF4E) were examined through western blot and immunofluorescence staining. HHT selectively reduced levels of p-eIF4E and its downstream oncoprotein Mcl-1, and potently inhibited in vitro and in vivo the growth of a distinct subset of AML cells and primary leukemia cells expressing high level of p-eIF4E through apoptosis. Our findings suggest that HHT might be a first-in-class p-eIF4E-targeted drug and offer a novel therapeutic option for AML patients expressing high level of p-eIF4E. [ABSTRACT FROM AUTHOR]

Based on the wave radiation and diffraction theory, this paper investigates a new type breakwater with upper arc-shaped plate by using the boundary element method (BEM). By comparing with other three designs of plate type breakwater (lower arc-shaped plate, single horizontal plate and double horizontal plate), this new type breakwater has been proved more effective. The wave exiting force, transmission and reflection coefficients are analyzed and discussed. In order to reveal the wave elimination mechanism of this type of breakwater, the velocity field around the breakwater is obtained. It is shown that: (1) The sway exciting force is minimal. (2) When the ratio of the submergence and wave amplitude is 0.05, the wave elimination effect will increase by 50% compared with other three types of breakwater. (3) The obvious backflow is found above the plate in the velocity field analysis. [ABSTRACT FROM AUTHOR]

Three new Ln4 clusters based on a bidentate Schiff base ligand having formulae [Ln4(μ3-OH)2L6(acac)4]·xCH3CN (Ln(iii) = Eu(1), Gd(2) and Dy(3), x = 1 for 1, x = 2 for 2, and x = 0 for 3, HL = 5-(4-o-hydroxybenzylidene)-8-hydroxylquinoline and acac = acetylacetone) have been successfully synthesized and completely characterized. The structures of 1–3 are similar to each other except for the nature of the central ion and the number of free acetonitrile molecules. The four LnIII ions are coplanar and clusters 1–3 have a butterfly-shaped arrangement. Magnetic studies show that cluster 2 displays a weak antiferromagnetic exchange interaction between nearby GdIII centers and exhibits magnetic refrigeration with maximum −ΔSm = 18.85 J kg−1 K−1 (ΔH = 7.0 T at 2.5 K). Alternating current (ac) magnetic susceptibility measurement of 3 indicates that 3 demonstrates SMMs behavior under a zero direct-current (dc) field, with an effective energy barrier (ΔE/kB) of 79.15 K and a pre-exponential factor τ0 = 5.82 × 10−8 s. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to investigate the correlation of katanin P80 expression with clinicopathological features and overall survival (OS) in surgical breast cancer (BC) patients. METHODS: Four hundred and fourteen BC patients underwent surgery were analyzed in this retrospective cohort study. Katanin P80 expression was examined by immunofluorescence assay. The median follow-up duration was 118.0 months (quantiles: 99.0–140.5 months), the last follow-up date was Jul 1st 2017. RESULTS: Eighty-five patients (20.5%) with katanin P80 positive expression and 329 patients (79.5%) with katanin P80 negative expression were observed in this research. Katanin P80 positive expression was correlated with higher N stage (p < 0.001) and TNM stage (p < 0.001). K-M curve and log-rank test revealed that katanin P80 positive patients presented with shorter OS compared with katanin P80 negative patients (p < 0.001). Multivariate Cox's regression analysis disclosed that katanin P80 positive expression (p < 0.001) and histologic grade (p < 0.001) could independently predict unfavorable OS. Furthermore, subgroups analysis was performed, which illuminated that katanin P80 positive expression was correlated with shorter OS in all subgroups divided by molecular subtyping and TNM stage (all p < 0.05) except in TNM stage I subgroup (p = 0.573). CONCLUSION: Katanin P80 expression positively correlated with lymph node metastasis and could abe a novel biomarker for prognosis in BC patients. [ABSTRACT FROM AUTHOR]

Controlled synthesis of amphiphilic block copolymer nanoparticles in a convenient way is an important and interest topic in polymer science. In this review, three formulations of polymerization-induced self-assembly to in situ synthesize block copolymer nanoparticles are briefly introduced, which perform by reversible addition-fragmentation chain transfer (RAFT) polymerization under heterogeneous conditions, e.g., aqueous emulsion RAFT polymerization, dispersion RAFT polymerization and especially the recently proposed seeded RAFT polymerization. The latest developments in several selected areas on the synthesis of block copolymer nano-assemblies are highlighted. [ABSTRACT FROM AUTHOR]

Two cationic heterometal–organic frameworks (Eu-Zn (1·NO3−) and Tb-Zn (2·NO3−)) with NO3− counter-anions in the channels are structurally and luminously characterized. Both of them can serve as highly sensitive and highly selective luminescent probes for detecting I− ions in aqueous solutions. In particular, 2·NO3− can selectively and reversibly detect I− with a fast response time of just 10 s and an extremely low detection limit of 0.001 ppm. Mechanism studies reveal that I− is quickly oxidized to form I3− with the help of 1·NO3− or 2·NO3−, leading to luminescence quenching. This represents the first report of MOF-based luminescent probes for the detection of I− in aqueous solutions. [ABSTRACT FROM AUTHOR]

Two 3D heterometal-organic frameworks based on infrequent trigonal bipyramidal Ln5 clusters as nodes were structurally and magnetically characterized (Ln=Gd ( 1), Dy ( 2)). The results indicate large MCE of up to 30.7 J kg−1 K−1 in 1 and slow magnetic relaxation behavior in 2. Expectedly, constructing 3D MOFs based on multinuclear clusters as nodes may will be a new strategy for achieving large −Δ Sm. Additionally, compound 1 exhibits high thermal and solvent stabilities, providing a favorable foundation for realistic applications. [ABSTRACT FROM AUTHOR]

A semiautomatic segmentation method based on active contour is proposed for computed tomography (CT) image series. First, to get initial contour, one image slice was segmented exactly by C-V method based on Mumford-Shah model. Next, the computer will segment the nearby slice automatically using the snake model one by one. During segmenting of image slices, former slice boundary, as next slice initial contour, may cross over next slice real boundary and never return to right position. To avoid contour skipping over, the distance variance between two slices is evaluated by an threshold. which decides whether to initiate again. Moreover, a new improved marching cubes (MC) algorithm based on 2D images series segmentation boundary is given for 3D image reconstruction. Compared with the standard method, the proposed algorithm reduces detecting time and needs less storing memory. The effectiveness and capabilities of the algorithm were illustrated by experimental results. [ABSTRACT FROM AUTHOR]

Iris recognition, as a biometric method, outperforms others because of its high accuracy. Iris is the visible internal organ of human, so it is stable and very difficult to be altered. But if an eye surgery must be made to some individuals, it may be rejected by iris recognition system as imposters after the surgery, because the iris pattern was altered or damaged somewhat during surgery and cannot match the iris template stored before the surgery. In this paper, we originally discuss whether refractive surgery for vision correction (LASIK surgery) would influence the performance of iris recognition. And experiments are designed and tested on iris images captured especially for this research from patients before and after refractive surgery. Experiments showed that refractive surgery has little influence on iris recognition. [ABSTRACT FROM AUTHOR]

Mean shift is a widely used clustering algorithm in image segmentation. However, the segmenting results are not so good as expected when dealing with the texture surface due to the influence of the textures. Therefore, an approach based on wavelet transform (WT), co-occurrence matrix (COM) and mean shift is proposed in this paper. First, WT and COM are employed to extract the optimal resolution approximation of the original image as feature image. Then, mean shift is successfully used to obtain better detection results. Finally, experiments are done to show this approach is effective. [ABSTRACT FROM AUTHOR]

Effects of the speed relaxation time on the optimal velocity car-following model (OVM) with delay time due to driver reaction time proposed by Bando et al. (1995) were studied by numerical methods. Results showed that the OVM including the delay is not physically sensitive to the speed relaxation times. A modified car-following model is proposed to overcome the deficiency. Analyses of the linear stability of the modified model were conducted. It is shown that coexisting flows appear if the initial homogeneous headway of the traffic flow is between critical values. In addition, phase transitions occur on varying the initially homogeneous headway. [ABSTRACT FROM AUTHOR]

A novel diversity-sampling based nonparametric multi-modal background model is proposed. Using the samples having more popular and various intensity values in the training sequence, a nonparametric model is built for background subtraction. According to the related intensities, different weights are given to the distinct samples in kernel density estimation. This avoids repeated computation using all samples, and makes computation more efficient in the evaluation phase. Experimental results show the validity of the diversity-sampling scheme and robustness of the proposed model in moving objects segmentation. The proposed algorithm can be used in outdoor surveillance systems. [ABSTRACT FROM AUTHOR]

Feature selection is a process where a minimal feature subset is selected from an original feature set according to a certain measure. In this paper, feature relevancy is defined by an inconsistency rate. A bidirectional automated branch and bound algorithm is presented. It is a new complete search algorithm for feature selection, which performs feature deletion and feature addition in parallel. Its bound is determined by inconsistency rate of the original feature set, hence termed as ‘automated’. Experimental study shows that it is fit for feature selection. [ABSTRACT FROM AUTHOR]

Taking into account the demands of hyperspectral remote sensing (RS) image retrieval and processing, some encoding methods of spectral vector including direct encoding, feature-based encoding and tree-based encoding methods are proposed and compared. In direct encoding, based on the analysis of binary encoding and quad-value encoding, decimal encoding is proposed. It is proved that quad-value encoding and decimal encoding are suitable to fast processing and retrieval. In absorption feature-based encoding method, five common metrics are compared. Because locations of reflection/absorption features are sensitive to noise, this method is not very effective in retrieval. In tree-based encoding methods, bitree, quadtree, octree and hextree are proposed and discussed. It is proved that 2-level octree and 2-level hextree are more effective than bitree and quadtree. Finally, quad-value encoding, decimal encoding, 2-level octree and 2-level hextree are proposed in spectral vectors encoding, similarity measure and hyperspectral RS image retrieval. [ABSTRACT FROM AUTHOR]

This paper discusses propagation of perturbations along traffic flow modeled by a modified second-order macroscopic model through the wavefront expansion technique. The coefficients in this expansion satisfy a sequence of transport equations that can be solved analytically. One of these analytic solutions yields information about wavefront shock. Numerical simulations based on a Padé approximation of this expansion were done at the end of this paper and results showed that propagation of perturbations at traffic flow speed conforms to the theoretical analysis results. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for off-line handwritten Chinese character recognition based on mergence of consecutive segments of adaptive duration. The handwritten Chinese character string is partitioned into a sequence of consecutive segments, which are combined to implement dissimilarity evaluation within a sliding window whose durations are determined adaptively by the integration of shapes and context of evaluations. The average stroke width is estimated for the handwritten Chinese character string, and a set of candidate character segmentation boundaries is found by using the integration of pixel and stroke features. The final decisions on segmentation and recognition are made under minimal arithmetical mean dissimilarities. Experiments proved that the proposed approach of adaptive duration outperforms the method of fixed duration, and is very effective for the recognition of overlapped, broken, touched, loosely configured Chinese characters. [ABSTRACT FROM AUTHOR]

This paper explores brain CT slices segmentation technique and some related problems, including contours segmentation algorithms, edge detector, algorithm evaluation and experimental results. This article describes a method for contour-based segmentation of anatomical structures in 3D medical data sets. With this method, the user manually traces one or more 2D contours of an anatomical structure of interest on parallel planes arbitrarily cutting the data set. The experimental results showed the segmentation based on 3D brain volume and 2D CT slices. The main creative contributions in this paper are: (1) contours segmentation algorithm; (2) edge detector; (3) algorithm evaluation. [ABSTRACT FROM AUTHOR]

Two unique 3D coordination polymers based on octahedral [Ln6] (Ln = Gd (1), Dy (2)) clusters as nodes were synthesized, exhibiting a novel (3,12)-connected topology with the symbol of (420·626·820)(43)4. The magnetic studies reveal that 1 shows a −ΔSm = 46.6 J kg−1 K−1, falling among the largest values known to date, and 2 displays slow magnetic relaxation behavior. Both 1 and 2 have high thermal and solvent stabilities. [ABSTRACT FROM AUTHOR]

Two novel Dy–Cu MOFs were structurally and magnetically characterized. The results reveal that it is the first example of anion-induced change of structure interpenetration and magnetic properties in 3d–4f MOFs. [ABSTRACT FROM AUTHOR]