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The dynamic interaction between the vehicle and track is strongly influenced by out-of-round wheels and turnout rail profile geometries, which result in high-magnitude contact forces and abnormal vibrations. This study presents the dynamic response of the tram-turnout interaction due to polygonal wheel wear and analyses its transmission between the wheelsets. A three-dimensional coupled tram-turnout dynamic model was formulated, taking into account the polygonal wear on the front bogie wheelsets. Through numerical simulations, the dynamic characteristics of a tram passing through the turnout switch and crossing panels under the influence of polygonal wear were simulated. Furthermore, the impact of polygonal wear amplitudes and tram speeds on the transmission of dynamic impact forces and vibrations from the front bogie wheelset to the trailer bogie wheels are described. According to the numerical findings, when the flexible wheelset experiences polygonal wear, it can lead to substantial impact forces and vibrations as the tram moves through the turnout switch and crossing zones. Moreover, the transmission of dynamic impact forces and vibrations from the front bogie wheelset to the trailer wheels increases as the wheel wear amplitude and the vehicle speed increase. [ABSTRACT FROM AUTHOR]

We propose a contemporaneous bilinear transformation for a p × q matrix time series to alleviate the difficulties in modeling and forecasting matrix time series when p and/or q are large. The resulting transformed matrix assumes a block structure consisting of several small matrices, and those small matrix series are uncorrelated across all times. Hence, an overall parsimonious model is achieved by modeling each of those small matrix series separately without the loss of information on the linear dynamics. Such a parsimonious model often has better forecasting performance, even when the underlying true dynamics deviates from the assumed uncorrelated block structure after transformation. The uniform convergence rates of the estimated transformation are derived, which vindicate an important virtue of the proposed bilinear transformation, that is, it is technically equivalent to the decorrelation of a vector time series of dimension max(p, q) instead of p × q. The proposed method is illustrated numerically via both simulated and real data examples. for this article are available online. [ABSTRACT FROM AUTHOR]

Catch and release has become a very popular fish conservation strategy and fisheries management tool. The physiological and behavioral changes in individuals who experience catch and release may be adaptive. These individuals may exhibit more cautious bait use or hook avoidance behavior when faced with lures again. Here, our study was conducted on crucian carp (Carassius auratus) to compare energy metabolism and personality (e.g. activity) before and after angling for three bouts of repeated angling. Our study showed that the standard metabolic rate, maximum metabolic rate, aerobic scope and factorial aerobic scope were all lower after three bouts of repeated angling, and the metabolic rates were greater before angling than after angling in the first two bouts of angling. In addition, the total magnitude of excess postexercise oxygen consumption after repeated angling also showed a decreasing trend as the number of angled bouts increased. The percentage of time spent moving increased after three bouts of repeated angling, but there were no changes in either individual swimming speed or total distance traveled. Our results suggest that repeated angling causes a high death rate and decreases the aerobic/anaerobic metabolic capacity of crucian carp, which may reduce their metabolic potential for other physiological functions, such as locomotion, growth and digestion. Future studies should continue to focus on the effects of fishing on the physiology, behavior, and population dynamics of fish. [ABSTRACT FROM AUTHOR]

To assess the impact of ankle-foot orthoses (AFOs) on mobility and gait during dual-task walking in post-stroke survivors. In this cross-sectional, factorial design trial, stroke survivors performed four randomized tasks: (1) dual-task walking with AFOs, (2) single-task walking with AFOs, (3) dual-task walking without AFOs, and (4) single-task walking without AFOs. Primary outcome was the Timed Up and Go (TUG) test, with secondary outcomes including gait metrics, Tinetti scores, and auditory N-back tests. In the results, 48 subjects (38 males and 10 females; 19-65 years) completed the trial. Patients had a greater TUG score with AFOs compared with non-AFOs conditions (95% CI: 7.22–14.41, P < 0.001) in single-task and dual-task conditions. Secondary outcomes showed marked enhancement with AFOs during dual-task walking, with significant interaction effects in gait metrics, balance, and cognitive function (P < 0.05). Although not statistically significant, dual-task effects of TUG and walking speed were more pronounced during dual-task walking. In conclusion, AFOs enhance mobility and gait during both single and dual-task walking in post-stroke survivors. [ABSTRACT FROM AUTHOR]

Thanks to the relevant spectral-spatial information, hyperspectral images (HSIs) have been widely exploited in Earth observation. Recently, graph convolutional networks (GCNs) have attracted increasing attention in HSI classification due to their advantages in processing non-Euclidean structure data. Unlike convolutional neural networks (CNNs), which perform convolution operations on regular square regions, GCNs can directly work on graph structure data to extract the relationships among adjacent land covers. However, extracting meaningful and deep discriminative spectral-spatial features from HSIs is still a challenging task. In this article, a novel multi-scale feature learning via residual dynamic graph convolutional network is designed for HSI classification, which can extract large-scale contextual spatial structures at superpixel-level graph and local spectral-spatial information at pixel-level, significantly improving the performance of HSI classification. Unlike from the existing GCN-based methods that operate on a graph with a fixed neighbourhood size, multiple graphs with diverse neighbourhood scales are built to comprehensively leverage spectral-spatial information and relationship at multiple scales, and these graphs are dynamically updated to generate more discriminative features (via dynamic GCN) during the convolution process. Moreover, to fully use the multi-scale features extracted from HSIs, a multi-scale feature fusion module is developed to emphasize important features and suppress irrelevant ones. Extensive experiments carried on three benchmark data sets demonstrate the superiority of the proposed approach over other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Rail joints are the weakest link in the railway track structure due to the presence of discontinuities in the track stiffness and wheel-rail contact geometry. This paper presents the dynamic response of vehicle-track interaction at the bolted rail joint (BRJ) in the presence of polygonal wheel wear. A three-dimensional coupled vehicle-track dynamic model was established using the finite element method (FEM) and the multi-body system (MBS) approach, in which the flexibilities of the wheelset and track are taken into account. The proposed dynamic model is validated by the comparisons of field measurement and calculated vertical axle-box acceleration in time and frequency domains. The effects of the flexible wheelset in the presence of polygonal wear on the vehicle-track dynamic interaction at the BRJs are illustrated through comparisons with those obtained using without polygonal wheel model. The results show that the polygonal wheel wear and the rail joint irregularities can induce high-magnitude vertical wheel-rail contact force, and exacerbate the vibration responses of the axle box, the wheelset, and the rails. The simulation results also indicate that the wheelset bending modes, the P2 resonance due to rail joint excitation, and the track vibration modes have significant effects on the vertical vehicle-track dynamic interaction at the supported and suspended BRJs. [ABSTRACT FROM AUTHOR]

Discovering underlying low dimensional structure of a high-dimensional matrix is traditionally done through low rank matrix approximations in the form of a sum of rank-one matrices. In this article, we propose a new approach. We assume a high-dimensional matrix can be approximated by a sum of a small number of Kronecker products of matrices with potentially different configurations, named as a hybrid Kronecker outer Product Approximation (hKoPA). It provides an extremely flexible way of dimension reduction compared to the low-rank matrix approximation. Challenges arise in estimating a hKoPA when the configurations of component Kronecker products are different or unknown. We propose an estimation procedure when the set of configurations are given, and a joint configuration determination and component estimation procedure when the configurations are unknown. Specifically, a least squares backfitting algorithm is used when the configurations are given. When the configurations are unknown, an iterative greedy algorithm is developed. Both simulation and real image examples show that the proposed algorithms have promising performances. Some identifiability conditions are also provided. The hybrid Kronecker product approximation may have potentially wider applications in low dimensional representation of high-dimensional data. for this article are available online. [ABSTRACT FROM AUTHOR]

Many massive data sets are assembled through collections of information of a large number of individuals in a population. The analysis of such data, especially in the aspect of individualized inferences and solutions, has the potential to create significant value for practical applications. Traditionally, inference for an individual in the dataset is either solely relying on the information of the individual or from summarizing the information about the whole population. However, with the availability of big data, we have the opportunity, as well as a unique challenge, to make a more effective individualized inference that takes into consideration of both the population information and the individual discrepancy. To deal with the possible heterogeneity within the population while providing effective and credible inferences for individuals in a dataset, this article develops a new approach called the individualized group learning (iGroup). The iGroup approach uses local nonparametric techniques to generate an individualized group by pooling other entities in the population which share similar characteristics with the target individual, even when individual estimates are biased due to limited number of observations. Three general cases of iGroup are discussed, and their asymptotic performances are investigated. Both theoretical results and empirical simulations reveal that, by applying iGroup, the performance of statistical inference on the individual level are ensured and can be substantially improved from inference based on either solely individual information or entire population information. The method has a broad range of applications. An example in financial statistics is presented. [ABSTRACT FROM AUTHOR]

This paper presents a multi-objective optimisation method considering the switch and stock rail profiles in the switch panel. Based on the non-uniform rational B-spline (NURBS) theory, a parameterised model of the measured turnout profile is constructed to determine the variables. This study selects the vehicle dynamic performance and wheel-rail contact damage as the objective function to establish a multi-objective optimisation mathematical model that is solved using NSGA- II. Overall performances of the measured profile and the optimised profile are compared and evaluated for two aspects, dynamic performance and wheel-rail contact damage. The following are the conclusions: The maximum lateral vibration acceleration of the axle box is reduced from 2.64–2.09 m/s2, which has a 20.83% decrease. Concerning wheel-rail contact damage, the maximum wear index is reduced from 13.46–11.47 N, the reduction is 14.78%. At the same time, the cumulative surface rolling contact fatigue (RCF) is reduced from 8.29×10−5–7.38×10−5. This article can provide a profile repair method for worn turnouts, which can maximise the comprehensive performance of the turnout within a limited amount of grinding, and can reduce the wheel-rail contact damage of the turnout while taking into account driving stability. [ABSTRACT FROM AUTHOR]

In this work, we report a controllable green synthesis of gold nanoparticles (AuNPs) using chlorogenic acid (CGA) as the only reducing and stabilizing agent. The well-dispersed AuNPs are obtained due to the protection of CGA against aggregation. The resulting AuNPs are controllable in size and shape mainly by changing the molar ratio of HAuCl4 to CGA in reductive process. With an increase in CGA concentration, the average size of AuNPs increased, which resulted in different morphologies from spherical to flower-like shapes. The dropping speed of gold precursor is also found to influence the size of AuNPs in different trends. Additionally, the advantages of CGA for synergistic biological activities are demonstrated through the enhanced antioxidant activity of AuNPs with CGA for scavenging of DPPH radicals. The controllable size and shape of nanoparticles are potentially important in nanomedical application. [ABSTRACT FROM AUTHOR]

This paper presents a method for the optimisation of wheel–rail profiles, and this is based on the relationships between the equivalent conicity, RRD curve and rail profile slope. This method can be used to improve the riding stability of trains when rolling across turnouts, and to optimise the equivalent conicity. The measured profile of a straight switch rail, i.e. a 60D40 rail laid in a high-speed turnout switch area, was taken as a sample for optimisation. The existing curve of equivalent conicity was lowered for reverse-reasoning calculation of the optimised profile. The optimised profile of the 60D40 rail was taken as the optimal design for an in-service straight switch rail. The effectiveness of the optimised design was then evaluated based on static wheel–rail contact and vehicle-turnout coupling dynamics. The conclusions show that, for an in-service straight switch rail, profile optimisation can effectively improve the wheel–rail relationship, thus enhancing the riding stability of trains in turnout switch areas. [ABSTRACT FROM AUTHOR]

This study investigates undergraduate STEM persistence through two-factor theory. Using nationally representative data and multinomial regression, we conceptualize known determinants of persistence as hygiene and motivator factors to test the persistence outcomes among college students who majored in STEM: earning a STEM degree, non-STEM degree, and degree non-completion. We propose that hygiene factors provide a baseline means of persistence in higher education, whereas the motivator factors improve the probability of student persistence in STEM majors. Our findings demonstrated that motivator factors improve the persistence model when added to hygiene factors. Hygiene factors were generally associated with STEM persistence by staying in college, while motivator factors mostly predicted persistence by remaining in the STEM major. Given the importance of motivator factors, we also tested the differential relationship between motivator factors and student persistence in STEM majors by gender and race/ethnicity due to underrepresentation in STEM fields. [ABSTRACT FROM AUTHOR]

The vibration performance of a tram vehicle running on the curved track is influenced by the speed of the running vehicle, the geometry of the track, the roughness of the wheel and rail, and environmental characteristics. This paper investigates the random vibration analysis of tram-track interaction on a curved track due to the polygonal wheel and track irregularity by the pseudo excitation method (PEM). The dynamic behaviour of tram-track interaction on a curve is modelled using the finite element method (FEM) and multi-body system (MBS). The field tests were carried out to acquire the rail vibration and deformation response, and also measuring the polygonal wheel wear profile to analyse and validate the dynamic behaviour tram-curved track model. The influence of the polygonal wheel on the vibration of tram-curved track coupled system and the wheel-rail contact responses are investigated by considering the wheelset flexibility. The results are illustrated through comparison between with and without the polygonal wheel in terms of time and frequency domain. The numerical results suggest that the wheelset flexibility under the polygonal wheel wear excitation would aggravate the vibration mode of the rail, car-body and axle-box, and also increase the dynamic wheel-rail contact force and creepage. [ABSTRACT FROM AUTHOR]

The keen observation is that, if Graph HT ht , then Graph HT ht has a block structure, with its ( I i i , I j i )-th block in the form of Graph HT ht where I a SB ij sb i is the ( I i i , I j i )-th element of Graph HT ht . In this case, Graph HT ht is in the form of Graph HT ht and we use SVD to estimate the column space of Graph HT ht . [Extracted from the article]

Large tensor (multi-dimensional array) data routinely appear nowadays in a wide range of applications, due to modern data collection capabilities. Often such observations are taken over time, forming tensor time series. In this article we present a factor model approach to the analysis of high-dimensional dynamic tensor time series and multi-category dynamic transport networks. This article presents two estimation procedures along with their theoretical properties and simulation results. We present two applications to illustrate the model and its interpretations. [ABSTRACT FROM AUTHOR]

The diagnosis and management of osteoporosis and osteoporotic fractures are challenging in rural and underdeveloped areas of China because medical resources are inaccessible; thus, a simple and accurate method is essential for the detection of vertebral fractures. We aimed to examine the relationship between historical height loss (HHL) and vertebral fractures in postmenopausal Chinese women. A cross-sectional study of 255 postmenopausal women aged 50 years or older was conducted in September 2017. Demographic data, including self-reported tallest historical height and current height were analyzed. Vertebral fractures were assessed using X-ray radiography and HHL thresholds were examined using specificity and sensitivity testing. The average age of the 255 participants was 66.3 ± 9.0 years and their mean HHL was 3.5 ± 2.8 cm. The 24 women who were found to have vertebral fractures were older, had more years since menopause (YSM), and a larger HHL compared to those without vertebral fractures. Logistic regression analysis showed that age was a better predictor of vertebral fractures than HHL was, and the cutoff age for detecting vertebral fractures was 71 years, with an area under the receiver operating characteristic curve of 0.750. Although the women in this study with vertebral fractures had a greater height loss than those without fractures, it was apparent that age, rather than HHL, is the best way to determine who is most likely to develop vertebral fractures. [ABSTRACT FROM AUTHOR]

In this paper, outcomes of the study on the bilinear forms and vector bright solitons for a coupled nonlinear Schrödinger system with variable coefficients are presented, which describes the simultaneous pulse propagation of the M-field components in an inhomogeneous optical fiber, where M is a positive integer. Under the integrable condition, we derive the bilinear forms, which are different from those in the existing literatures, and obtain the bright N-soliton solutions, where N is a positive integer. When M = 3, via the asymptotic analysis, we find that the amplitudes of the bright solitons are dependent on the amplification/absorption effect, $ \Gamma (z) $ Γ (z) , and the velocities of the bright solitons are related to the group velocity dispersion, $ \Lambda (z) $ Λ (z) , where z represents the spatial coordinate. Head-on, overtaking and inelastic interactions, and bound states between the two solitons are presented. We extend our analysis to M fields to obtain the vector bright N-soliton solutions. [ABSTRACT FROM AUTHOR]

Context: Triptolide (TP) has outstanding biological activities, but it induces toxicities, particular hepatotoxicity, severely limiting its clinical application. Chlorogenic acid (CGA) has prominently medicinal and nutritional values. However, until now, it is not known whether CGA could mitigate TP-induced hepatotoxicity. Objective: This study explored the possible protection of CGA against TP-induced hepatotoxicity and its potential mechanisms, for the first time. Material and methods: KM mice were treated orally with TP at a single dose of 1 mg/kg at 4 h after being treated with CGA (10, 20 and 40 mg/kg) for seven continuous days. Blood samples were collected at 24 h after TP administration for measurement of serum biomarkers, and hepatic tissues for analysis of potential mechanisms. Results: TP treatment-induced acute hepatotoxicity manifested by the significant elevation in serum alanine transaminase (93.9 U/L), aspartate transaminase (185.8 U/L) and hepatic malondialdehyde (0.637 μmol/mg protein), and the remarkable reduction in hepatic glutathione (1.425 μg/mg protein), glutathione S-transferase, glutathione peroxidase, superoxide dismutase and catalase (91.7, 320.7, 360.6 and 140.7 U/mg protein, respectively). In contrast, pretreatment with CGA for 7 days effectively attenuated acute liver injury and oxidative stress caused by TP with each ED50 of 44.4, 57.1, 46.6, 22.2, 40.9, 58.1, 86.4 and 61.0 mg/kg, respectively. Furthermore, pretreatment with CGA promoted the accumulation of Nrf2 into the nucleus, and up-regulated mRNA expression of Nrf2-target downstream genes. Discussion and conclusions: Combined CGA medication may probably reduce the risk of TP poisoning, and in-depth mechanisms can be developed around the signal molecules of Nrf2. [ABSTRACT FROM AUTHOR]

The secret sharing schemes based on the Chinese Remainder Theorem (CRT) and their applications have attracted many researchers in recent years. In this paper, we propose a weighted threshold secret sharing scheme based on the CRT and prove the scheme is asymptotically perfect. Since all CRT-based secret sharing schemes use special sequences of pairwise coprime integers as its parameters, this paper proposes the first algorithm to generate these integers. Moreover, the correctness of this algorithm is proved by using the prime number theorem. The experimental result shows the effectiveness and the efficiency of our algorithm as well as the space efficiency of our scheme using the sequences of integers generated from our algorithm. Our scheme with the parameter generation algorithm can be used in many applications such as threshold cryptosystems. [ABSTRACT FROM AUTHOR]

The novel green terbium single-doped or terbium and sodium codoped barium zinc phosphate phosphors were successfully synthesized by a high temperature solid-state reaction. Terbium single-doped and terbium and sodium codoped barium zinc phosphate phosphors can be efficiently excited by near ultraviolet (n-UV) light, and the emission spectrum consists of four main emission peaks at 495, 545, 589, and 622 nm. By increasing the terbium concentration, the emission signal of the phosphor can reach the maximum at 0.09 molar terbium, then the content quenching occurs. By introducing the charge compensator sodium ions into the terbium-doped barium zinc phosphate phosphors, its emission signal can be obviously enhanced. The Commission International de l’Eclairage chromaticity coordinates of the two typical samples are (0.30, 0.47) and (0.31, 0.48), which are both in the green region. The decay time and quantum yield of the typical sample are 365.84 µs and 0.49, respectively. All the results indicate that terbium single-doped and terbium and sodium codoped barium zinc phosphate are promising green phosphors for near ultraviolet pumped white light-emitting diodes. [ABSTRACT FROM AUTHOR]

In this paper, hot-melt extrusion was applied to prepare drug delivery systems using polylactide acid (PLA) as the matrix. Diclofenac sodium (DS) was used as a model drug. Polyethylene glycol (PEG, molecular weight is 6000) and sodium dodecyl sulfate (SDS) were used as the release rate modifiers. For the PLA/PEG/DS blends, the release of DS was enhanced with higher amounts of PEG and DS. After the addition of SDS to the PLA/PEG/DS blends, the dispersion of DS and PEG was significantly improved. Compared to the PLA/PEG/DS blends with the same drug loading, the drug release behavior of PLA/PEG/DS/SDS was remarkably suppressed due to the presence of SDS. And a controllable linear release of DS was achieved. [ABSTRACT FROM AUTHOR]

Sequential Monte Carlo is a useful simulation-based method for online filtering of state-space models. For certain complex state-space models, a single proposal distribution is usually not satisfactory and using multiple proposal distributions is a general approach to address various aspects of the filtering problem. This article proposes an efficient method of using multiple proposals in combination with control variates. The likelihood approach of Tan (2004) is used in both resampling and estimation. The new algorithm is shown to be asymptotically more efficient than the direct use of multiple proposals and control variates. The guidance for selecting multiple proposals and control variates is also given. Numerical examples are used to demonstrate that the new algorithm can significantly improve over the bootstrap filter and auxiliary particle filter. [ABSTRACT FROM AUTHOR]

A simple method was developed for the determination of hydrophilic whitening agents (ascorbyl glucoside, magnesium ascorbyl phosphate, arbutin, hydroquinone, and kojic acid) in bleaching cosmetics by high performance liquid chromatography with electrochemical detection. The samples were prepared using microdialysis and were separated within ten minutes using isocratic elution. Linear calibration was achieved for concentrations between 0.10 and 10.00 micromolar. The limits of detection were from 0.6 to 2.0 nanomolar; the recoveries were between 91.43 and 108.04 percent, and the relative standard deviation was less than 6.88 percent. This method was used to determine whitening compounds in several cosmetics with on-line microdialysis and the zero net flux method. The procedure was fast, simple, selective, and suitable for routine analysis. [ABSTRACT FROM PUBLISHER]

A rapid and underivatized method for the determination of glutamine (Gln) in human serum was developed using ultra performance liquid chromatography tandem mass spectrometry (UPLC/MS/MS). Gln was eluted in an Acquity UPLC BEH Amid column. The chromatographic separation was performed with an isocratic mobile phase consisting of acetonitrile and ammonium formate. The analyses were carried out by select reaction monitoring using the precursor-to-product combinations of m/z 146.8→83.6 (Gln) and m/z 103.4→57.7 (IS). Validation results indicated that the lower limit of quantification was 30 μg mL−1 and the assay exhibited a linear range of 30-600 μg mL−1. A typical equation for the calibration curve was y = 0.0039 x + 0.0139 ( r2 = 0.9992). The intra-batch precision (relative standard deviation, RSD) was less than 5.4% and inter-batch (RSD) was less than 9.2%, while accuracy was from 93.11 to 101.39% and from 96.22 to 99.62%, determined from quality control (QC) samples for Gln. Then the established method was successfully applied to determine the Gln concentration in the serum of healthy human and pregnant woman within three-month pregnancy. The results showed that the Gln concentration in pregnant woman serum was generally lower than the healthy human group. It suggests that the pregnant woman should eat more food packed with Gln. [ABSTRACT FROM AUTHOR]

Rotatory inertia due to the shear deformation is usually neglected for all engineering beam models. This article, however, introduces a novel beam model that further considers the rotatory inertia caused by the shear deformation, based on the Timoshenko beam model. The equation of motion for the proposed beam model is derived. Its dynamic characteristics, including wave and vibration characteristics, are studied in detail. Numerical simulations are conducted and related issues are discussed. It is found that the improvement is negligible when the wave number or vibration order is small for thin beams. However, the improvement is evident when the wave number or vibration intensity is fairly large for thick beams. This research finding reveals that only one frequency spectrum, one set of the wave phase velocities, and one set of group velocities should be considered in Timoshenko-type beams. This finding can help settle the debate in the literature on how many frequency spectra should be considered for these analyses. This research study shows that the proposed new beam model is more reasonable, accurate, and it is a more realistic model. [ABSTRACT FROM AUTHOR]

This paper deals with the Cauchy problem for a generalized Dullin–Gottwald–Holm (DGH) equation. The local well-posedness of the generalized DGH equation is obtained in Besov spacewithandby the transport equations theory and the classical Friedrichs regularization method. Moreover, the local well-posedness in critical caseis also considered. Then a lower bound for the maximal existence time of the solution is derived. Finally, the analytic of the solution is given. [ABSTRACT FROM AUTHOR]

Urban population size dynamic adjustment has been widely studied for a long time; however, the dynamic adjustment at the urban hierarchy level remains unknown. This study utilises China's urban population data to investigate the dynamic adjustment. Specifically, we utilise methods of the Gini coefficient, linear regression, and coefficients of Spearman, and Moran's I to explore the dynamic adjustment tendency, adjustment rate and correlation of urban population size distribution of different urban hierarchies and groups of different urban hierarchies. We find that the urban population size spatial distribution is gradually even within the same urban hierarchy. The adjustment rate to be even of Megacity II is the highest, and Megacity I is the bottom. We also find the population size spatial distribution of the whole urban system is gradually uneven. We explore the dynamic process by sorting urban hierarchies into six groups. Furthermore, we find there is a complex correlation between different urban hierarchies and global spatial correlation among China cities. These results are valuable as references for Chinese policy-makers and practitioners and will enable them to adopt sustainable land use and urban population management measures. The study outcomes will also benefit future studies on spatial population size distribution in international communities. [ABSTRACT FROM AUTHOR]

This article examines debt burden among college graduates and contributes to previous research by incorporating institutional and state characteristics. Utilizing a combination of national datasets and zero-one inflated beta regression, we find several major themes. First, family income and college experiences are strongly associated with the probability of zero debt burden as well as the level of debt burden. Second, graduates from private institutions have a higher level of debt burden than graduates from a public institution. Lastly, state funding of merit-based aid programs play a role in reducing students' debt burden, but the effect disappears when accounting for the "Georgia effect." Conclusions and suggestions are made about the roles institutions and government can play in reducing debt burden among college graduates. [ABSTRACT FROM AUTHOR]

A semi-distributed model with a parallel connection was applied to examine the effects of urbanization variables. Data were obtained from watershed divisions that were characterized by various degrees of urbanization. The mean rainfall was calculated using the kriging method. The model inputs were obtained by subtracting mean rainfall fromФ-index values, based on the spatially uniform loss assumption. Regression analysis was applied to determine the relationship between the parameters of 64 calibrations and urbanization variables among the divisions. The results showed that overland parameters produced more consistent change in response to imperviousness than to population. Conversely, the channel parameter was unaffected by changes in urbanization. The verification results of 46 cases showed that power linkage was a potential option for linking division parameters with the corresponding imperviousness based on four evaluation criteria. The changes in imperviousness on overland parameters show the hydrological effects of division urbanizations.Editor D. Koutsoyiannis; Associate editor T. WagenerCitation Chen, R., Chuang, W.-N., and Cheng, S., 2014. Effects of urbanization variables on model parameters for watershed divisions. Hydrological Sciences Journal, 59 (6), 1167–1183. http://dx.doi.org/10.1080/02626667.2014.910305 [ABSTRACT FROM AUTHOR]

Terraced paddy fields play a crucial role in water and soil conservation because their water-storage capacity reduces flood peaks in mountainous areas. The water-storage capacity of a paddy field is mainly dependent on the size of the field, the height of the bund, and the outlet within the bund. However, the height of the bund and outlet can be reduced due to a lack of maintenance, especially when rice paddies have been abandoned. This study assessed the flood-control function of a terraced paddy field during heavy-rainfall events. The four-layered tank model calibrated byin siturainfall–runoff measurements was applied to determine the effects of reducing the height of the bund and the outlet within the bund, on the drainage peak flow of terraced fields. The simulation results from two heavy-rainfall events indicated the excellent flood-control function of terraced paddy fields. The simulation results showed that the drainage peak flow underwent considerable changes when the height of the bund and outlet was reduced by more than 50%. Therefore, sustainable rice planting in the terraced paddies or maintenance of the water-storage capability in abandoned arable land is necessary to release downstream flood pressure.Editor D. Koutsoyiannis; Associate editor S. YueCitation Chen, S.-K., Chen, R.-S., and Yang, T.-Y., 2014. Application of a tank model to assess the flood-control function of a terraced paddy field. Hydrological Sciences Journal, 59 (5), 1020–1031. [ABSTRACT FROM PUBLISHER]

Adenovirus is a common infectious pathogen in both children and adults. It is a significant cause of morbidity in immunocompetent people living in crowded living conditions and of mortality in immunocompromised hosts. It has more recently become a popular vehicle for gene therapy applications. The host response to wild-type infection and gene therapy vector exposure involves both virus entry receptor and the innate immune systems. Cell-mediated recognition of viruses via capsid components has received significant attention, principally thought to be regulated by the coxsackievirus-adenovirus receptor (CAR), CD46, integrins and heparin sulfate-containing proteoglycans. Antiviral innate immune responses are initiated by the infected cell, which activates the interferon response to block viral replication, while simultaneously releasing chemokines to attract neutrophils and NK cells. This review discusses the innate immune response primarily during wild-type adenovirus infection because this serves as the basis for understanding the response during both natural infection and exposure to adenovirus vectors. [ABSTRACT FROM AUTHOR]

Discontinuous particle films of polystyrene (PS) with different molecular weights were prepared by the methods of spin coating (SPC) and droplet evaporation (DE) at room temperature on mica substrates. Visualization and characterization of these samples were performed by atomic force microscopy (AFM). The results showed that the dimensions of the particles in the films increased with molecular weight. The dimensions of the particles in the films derived from SPC exhibited better uniformity than those from DE. During the steps of particle film formation by SPC, the PS molecules gathered in large clusters at the early stage, then the polymer aggregates were separated or spun off, and more and more particles emerged, finally the clusters vanished and the particle film formed. The particles of the spin-coated film dewetted after annealing and numerous individual polymer chains appeared newly on the mica substrate. [ABSTRACT FROM AUTHOR]

This study is primarily focused on the influence of horizontal longitudinal vibrations and the condensation section temperature on the heat transfer performance of a grooved cylindrical copper heat pipe, with a length of 600 mm and an outer diameter of 8 mm. Longitudinal vibrations with frequencies of 3, 4, 5, 6, and 9 Hz and amplitudes of 2.8, 5, 10, 15, 20, and 25 mm, which would give accelerations in the range of 0.1–1.01 g, were experimentally tested. The condensation section temperature was set at 20, 30, or 40°C. A heating jacket and a cooling sleeve were installed at the evaporation and condensation sections of the test cell to mimic a constant heat flux and a constant temperature boundary, respectively. When the heat pipe started to vibrate horizontally in the longitudinal direction, this vibration caused an increase in the heat transfer of the heat pipe that was directly proportional to the input vibration energy below 500 mm2 Hz2. When the value of the vibration energy exceeded this value, the heat transfer enhancement per unit vibration energy decreased rapidly. Along with the decrease in the condensation section temperature, the average temperature of the heating section decreases. The influence of the condensation section temperature on the maximum heat transfer is much greater than that of the vibrations. [ABSTRACT FROM PUBLISHER]

The article presents research regarding ways in which U.S. state policies for funding higher education impact student admissions and enrollment at universities. A brief history of student financial aid programs in the U.S. is provided which includes a description of the federally funded Pell Grant program and the shift in policy to need-based student aid during the 1980s. Particular focus within the research is paid to the relationship between higher education financing policies and the socioeconomic status (SES) and racial characteristics of students.

Additive models have been widely used in nonparametric regression, mainly due to their ability to avoid the problem of the 'curse of dimensionality'. When some of the additive components are linear, the model can be further simplified and higher convergence rates can be achieved for the estimation of these linear components. In this paper, we propose a testing procedure for the determination of linear components in nonparametric additive models. We adopt the penalised spline approach for modelling the nonparametric functions, and the test is a sort of Chi-square test based on finite-order penalised spline estimators. The limiting behaviour of the test statistic is investigated. To obtain the critical values for finite sample problems, we use resampling techniques to establish a bootstrap test. The performance of the proposed tests is studied through simulation experiments and a real-data example. [ABSTRACT FROM AUTHOR]

The article presents a study examining racial/ethnic gaps in dropout risk in higher education and whether the gaps are affected by the provision and timing of financial aid. It asks questions including how differing types and amounts of financial aid are distributed by race and ethnicity, what differences exist in college dropout risk for students from various racial/ethnic backgrounds in four-year schools, and whether and how financial aid affects student dropout risks by race and ethnicity. It concludes that minority students have lower dropout risks when awarded larger Pell Grants, and that subsidized loans have a greater impact than non-subsidized loans.

Adsorption of thiocyanate anions (SCN-) induced by electrochemical polarization on active carbon felt (ACF) electrode was measured in a three-electrode cell by UV spectroscopy for the application of the electrosorption technique in the removal of SCN- in water. Positive polarization of the ACF electrode causes a dramatic increase in the adsorption of SCN- and negative polarization causes desorption of most of SCN- from the ACF electrode. The reversibility of electrosorption is remarkably affected by current intensity, solution pH, and the co-existed ions. The fully reversible electrodesorption of SCN- occurs in basic solution with pH 9.68. Electrochemical oxidation of partial SCN- decreases this reversibility under stronger polarization. The stronger adsorption of SCN- on open circuit in acid solution and the competition of [image omitted] with SCN- also results in the decreased reversibility of electrosorption. [ABSTRACT FROM AUTHOR]

Although the spatial and temporal distributions of cellular NAD(P)H concentrations have been theoretically predicted as typical patterns of the metabolism in living cells, so far such a pattern was observed only in neutrophils. In this work, the dynamic NAD(P)H distributions in rat basophilic leukemia (RBL-2H3) and human hepatocellular carcinoma (Hep G2) cells were studied by imaging the autofluorescence of cellular NAD(P)H with a sensitive CCD detector in a confocal microscope. The typical pattern of the cytoplasmic NAD(P)H wave traveling along the long axis of the elongated cell with a velocity of 2.2±0.6 μm/s was detected in RBL-2H3 cells. While in the case of Hep G2 cells, only the oscillation of the mitochondrial NAD(P)H was observed because the NAD(P)H mainly localized in mitochondria of Hep G2 cells. These results confirm the metabolic pattern of NAD(P)H in living cells and suggest that the expression of the metabolic pattern probably differs in different cell lines. [ABSTRACT FROM AUTHOR]

In the present study, we examined GC nucleotide composition, relative synonymous codon usage (RSCU), effective number of codons (ENC), codon adaptation index (CAI) and gene length for 308 prokaryotic mechanosensitive ion channel (MSC) genes from six evolutionary groups: Euryarchaeota, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Firmicutes, and Gammaproteobacteria. Results showed that: (1) a wide variation of overrepresentation of nucleotides exists in the MSC genes; (2) codon usage bias varies considerably among the MSC genes; (3) both nucleotide constraint and gene length play an important role in shaping codon usage of the bacterial MSC genes; and (4) synonymous codon usage of prokaryotic MSC genes is phylogenetically conserved. Knowledge of codon usage in prokaryotic MSC genes may benefit from the study of the MSC genes in eukaryotes in which few MSC genes have been identified and functionally analysed. [ABSTRACT FROM AUTHOR]

The separation of 1,1′-bi-2-naphthol racemic mixtures, using the eight-column simulated fmoving-bed (SMB) method with chiral columns of Pirkle D-phenylglycine and each column length of 10 cm, was investigated experimentally in this study. A quick method was used to determine the optimal operating conditions for the SMB system. This was based on the “triangle theory,” and good separation conditions were found based on the experimental results of a series of SMB experiments conducted around the complete separation region of the “triangle theory.” The optimal operating conditions for each of the solvent composition systems (hexane/IPA = 90/10, 80/20, 70/30) were found, and the effect of solvent compositions on the SMB system performance was studied based on the above quick method. Good system performance (with purity and recovery higher than 97% and productivity higher than 0.44 mg/min of each isomer) was achieved using 80/20 hexane/IPA as eluent, which was found to be a suitable solvent composition for our SMB system. [ABSTRACT FROM AUTHOR]

A rapid and accurate high performance liquid chromatography (HPLC) method is described for simultaneous determination of piperacillin sodium and sulbactam sodium in sterile powder for injection. Chromatographic separation of the two drugs was achieved on a Diamonsil C18 column (150 × 4.6 mm, 5 µm) using a mobile phase consisting of a mixture of methanol and 0.01 M tetrabutylammonium hydroxide (TBAH) (50 : 50, v/v). The flow rate was 1.0 mL/min and detection was made at 220 nm. Salicylic acid was used as internal standard. Separation was completed in less than 15 min. The method was validated for system suitability, linearity, accuracy, precision, limit of quantitation, and robustness. The linear range for piperacillin sodium and sulbactam sodium was 103.0–1030.0 µg/mL and 24.0–240.0 µg/mL, respectively. Limit of quantitation (LOQ) was 22.05 µg/mL for piperacillin sodium and 5.48 µg/mL for sulbactam sodium. Relative standard deviation (RSD), for piperacillin sodium and sulbactam sodium was less than 1.0 and 1.2%, respectively. [ABSTRACT FROM AUTHOR]

The objectives of this study were to explore the effects of coating with watersoluble chitosans of different molecular weights and concentrations on vesicle size, size distribution, stability, and apparent viscosity of liposomes. The results indicate that the vesicle size of liposomes coated with different concentrations and different molecular weights of water-soluble chitosans decreased with increasing passes of microfluidizing treatment, then reached a constant value. Liposomes subjected to the same microfluidization treatment were larger for those coated with a higher concentration (of the same molecular weight chitosan) or coated with a lower molecular weight (at the same concentration) of water-soluble chitosans. The average particle size of liposomes coated with different molecular weights of water-soluble chitosans decreased with increasing number of passes of microfluidizing treatment. The apparent viscosity of liposomes coated with water-soluble chitosans decreased after the first pass, then reached a constant value after the third pass of microfluidizing treatment. Apparent viscosities of liposomes subjected to different passes of microfluidization treatment were larger for those coated with a higher concentration or a higher molecular weight of water-soluble chitosans. Liposomes coated with 0.5% of different molecular weights of water-soluble chitosans behaved as pseudoplastic fluids. At the same shear rate, the apparent viscosities of liposomes subjected to more passes of microfluidizing treatment were larger than those subjected to fewer passes of microfluidizing treatment. Liposomes coated with water-soluble chitosans are more stable than those without a coating. [ABSTRACT FROM AUTHOR]

AbstractA series of cyclic triaxial tests were conducted on marine soft clay deposits to establish and validate a predictive model for cumulative plastic strain. Additionally, a numerical model of particle flow code in cyclic triaxial tests was developed. The effects of confining pressure, moisture content, and dynamic stress ratio on the dynamic properties of marine soft clay were examined, considering factors such as volume deformation and microscopic failure patterns. The results indicated that both the predictive model and numerical model showed strong consistency with the experimental data. The plastic strain of marine soft clay was influenced by moisture content, stress ratio, and confining pressure in a consistent manner, with moisture content being the primary factor. A predictive model for the cumulative plastic strain of marine soft clay was successfully established, allowing for the evaluation of dynamic properties from the perspective of cumulative plastic strain. During the loading process in the numerical model, microcracks within the soil structure gradually compacted, and the main displacement of the specimen extended from the vertical center axis to the sides, ultimately resulting in shear damage. [ABSTRACT FROM AUTHOR]

Ovary benign clear cell adenofibroma (CCAF) is extremely rare. Here, we reported a 38-year-old woman with CCAF who was given sequential cyclic hormone replacement therapy for eight years due to premature ovarian failure (POF). At operation, we found adenofibromas in both ovaries and well encapsulated. The cut surface was cystic and solid in appearance, and multilocular cysts embedded in hard stroma. Determination of sex hormone levels in the fluid of cysts of the ovary showed normal level. Clear cell cystadenofibroma proliferation was found in ovarian stroma while atrophy in ovarian cortex. Histological examination revealed that the glands were lined by 1 or 2 layers of hobnail cells with scant to moderate pale or clear cytoplasm. The nuclei were small uniform, and flat to round. Neither primary follicles nor secondary follicles were observed in ovary cortex. Immunohistochemical results showed that EMA and p53 were positive while Calretinin was negative. In this article, we reviewed literatures and analyzed both clinical and pathological features of ovary benign clear cell adenofibromas. [ABSTRACT FROM AUTHOR]

For a coupled nonlinear Schrödinger system with the negative coherent coupling, which describes two orthogonally polarized pulses in a weakly birefringent fibre, we construct the Darboux dressing transformation and the N-th-order breather solutions with N as a positive integer. When the retarded time tends to be infinite, limits of the ratios between the N-th-order breather solutions and seed solutions are obtained. For the first-order breathers, we present the condition to distinguish the degenerate and nondegenerate cases. For the nondegenerate breathers, we analyse whether the breathers could be kink-type based on the above limits. For the second-order breathers, superregular breathers (SRBs) are derived, where each SRB could consist of two (1) kink-type, (2) single-hump or (3) double-hump quasi-Akhmediev breathers (quasi-ABs). Before and after the interaction, profiles of two quasi-ABs change for Case (1) but keep unchange for Case (2) or (3). [ABSTRACT FROM AUTHOR]

The pathogenesis of renal osteopathy and cardiovascular disease suggests the disordered bone–vessel axis in chronic kidney disease–mineral bone disorder (CKD–MBD). However, the mechanism of the bone–vessel axis in CKD–MBD remains unclear. We established a CKD–MBD rat model to observe the pathophysiological phenotype of the bone–vessel axis and performed RNA sequencing of aortas to identify novel targets of the bone–vessel axis in CKD–MBD. The microarchitecture of the femoral trabecular bone deteriorated and alveolar bone loss was aggravated in CKD–MBD rats. The intact parathyroid hormone and alkaline phosphatase levels increased, 1,25-dihydroxyvitamin D3 levels decreased, and intact fibroblast growth factor-23 levels did not increase in CKD–MBD rats at 16 weeks; other bone metabolic parameters in the serum demonstrated dynamic characteristics. With calcium deposition in the abdominal aortas of CKD–MBD rats, RNA sequencing of the aortas revealed a significant decrease in inositol 1,4,5-trisphosphate receptor type 2 (ITPR2) gene levels in CKD–MBD rats. A similar trend was observed in rat aortic smooth muscle cells. As a secretory protein, ITPR2 serum levels decreased at 4 weeks and slightly increased without statistical differences at 16 weeks in CKD–MBD rats. ITPR2 serum levels were significantly increased in patients with vascular calcification, negatively correlated with blood urea nitrogen levels, and positively correlated with serum tartrate-resistant acid phosphatase 5b levels. These findings provide preliminary insights into the role of ITPR2 in the bone–vessel axis in CKD–MBD. Thus, ITPR2 may be a potential target of the bone–vessel axis in CKD–MBD. [ABSTRACT FROM AUTHOR]

A colour image encryption scheme based on Gaussian apertured real-preserving fractional Mellin transform (GARPFrMT) in diffraction domain and chaos permutation is proposed. Real-preserving fractional transform in diffraction domain using Gaussian aperture is constructed to ensure that the output is real, which is convenient for storage and communication. And the Gaussian aperture, as a soft aperture, can improve the intensity distributions of the output light, which contributes to prevent possible attacks for obtaining some useful information from the marginal leakage of light in the optical encryption systems. The colour space rotation transform is first used to convert the colour image from standard R G B space to R ′ G ′ B ′ space. And then, the three new colour components are transformed by GARPFrMT with three different diffraction channels, respectively. A 3D-logistic map is utilized to further scramble the three-colour components. At last, a logistic-sine map is used to perform Xor operation with three components, respectively. Simulation results demonstrate that the proposed algorithm is feasible and robust to noise attack and data loss. [ABSTRACT FROM AUTHOR]

High-dimensional matrix-variate time series data are becoming widely available in many scientific fields, such as economics, biology, and meteorology. To achieve significant dimension reduction while preserving the intrinsic matrix structure and temporal dynamics in such data, Wang, Liu, and Chen proposed a matrix factor model, that is, shown to be able to provide effective analysis. In this article, we establish a general framework for incorporating domain and prior knowledge in the matrix factor model through linear constraints. The proposed framework is shown to be useful in achieving parsimonious parameterization, facilitating interpretation of the latent matrix factor, and identifying specific factors of interest. Fully utilizing the prior-knowledge-induced constraints results in more efficient and accurate modeling, inference, dimension reduction as well as a clear and better interpretation of the results. Constrained, multi-term, and partially constrained factor models for matrix-variate time series are developed, with efficient estimation procedures and their asymptotic properties. We show that the convergence rates of the constrained factor loading matrices are much faster than those of the conventional matrix factor analysis under many situations. Simulation studies are carried out to demonstrate finite-sample performance of the proposed method and its associated asymptotic properties. We illustrate the proposed model with three applications, where the constrained matrix-factor models outperform their unconstrained counterparts in the power of variance explanation under the out-of-sample 10-fold cross-validation setting. for this article are available online. [ABSTRACT FROM AUTHOR]

IL-10-producing B Cells (B10) is a functionally defined regulatory B-cell subset. It plays an important role in the control of inflammation and autoimmune diseases, although it is present at low numbers in peripheral blood. Graves' disease is an autoimmune disease characterized by the production of autoantibodies such as TRAb. ILC2s maintains Th2 polarization state by producing type-II cytokines. It is not clear whether the level of autoantibody is related to ILC2s and B10 cells in Graves' disease. In this study, we analyzed the frequencies of B10, Treg cells and ILC2s, as well as the expression of related cytokines in peripheral blood from patients with Graves' disease and evaluated the correlation between B10 cell numbers and autoantibodies level. Our data showed that the frequency of B10 or Treg cells was significantly decreased in peripheral blood mononuclear cells from Graves' disease patients, while the percentage of ILC2s cells was increased; the levels of cytokine IL-5, IL-13 and related transcription factor RORα were up-regulated. Autoantibodies analysis also showed that high level of TRAb was accompanied by low rates of B10 cells in patients, there was a negative correlation trend. In addition, the analytical data from mouse disease models also showed similar results. It indicates that B10 cells may affect the production of TRAb by negative regulation of Th2 cells, while ILC2s can promote the production of autoantibodies such as TRAb by maintaining the dominant response state of Th2 cells. [ABSTRACT FROM AUTHOR]

It is of particular importance to be able to properly describe the complex alternating loads on a high-speed turnout, in order to accurately analyse fatigue damage and predict the fatigue life of the overall turnout structure. To this end, a vehicle-turnout rigid-flexible coupling dynamics model that considers the randomness of actual vehicle parameters and track conditions was built for this paper. The load-time history of turnout rails was traced under random conditions to systematically analyze the actual change in load characteristics on the straight switch rail. Finally, the fatigue damage and life of the straight switch rail were predicted based on the Multi-load step stress analysis, S-N curve and Miner's principle of damage accumulation. The results showed that complex random excitation caused a change in load sequence on the straight switch rail, while the fatigue-sensitive area extended backwards to the cross-sections with a top width of 45-55 mm. The severest fatigue damage was observed on the cross-section of the straight switch rail with a top width of 50 mm. The result remains the same as the fatigue damage zone of the on-site straight switch rail, which verifies the accuracy of the calculation. [ABSTRACT FROM AUTHOR]