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Providing effective Through Train Services (TTSs) faces challenges due to complex infrastructure conditions, train performances and passenger demands. To enhance TTSs between two different classes of urban rail transit lines with variations in train speed and capacity, we propose a multi-objective Integer Non-Linear Programming (INLP) model. This model maximizes passenger travel time savings and average train load utilization, and develops an integrated approach to simultaneously optimize the frequencies of through express trains and local trains, as well as the operation zones, stopping patterns and type selection of through trains. Additionally, a Non-Dominated Sorting Genetic Algorithm II is designed to solve the INLP model based on a simple test network and a real-world case from the Nanjing Subway. The unique benefits of our proposed method are demonstrated by a comprehensive compared with the Single Line Operation Mode and the all-stop plans under Through Operation Mode. [ABSTRACT FROM AUTHOR]

External impact is one of the potential hazards for in-service subsea pipelines. The stress concentration by external impact can create a dent that affects the pipeline's ultimate bearing capacity. In this paper, a theoretical model based on the string-on-plastic foundation is established to model the local indentation of pressurised pipelines by a wedge indenter. The effects of internal pressure and boundary conditions on the denting process are investigated. With this model, the relationship between the indenting force and the dented depth is obtained under a set of two boundary conditions. The accuracy of the new analytical models is validated by comparing them with the specification and numerical simulation model. It is believed that the new analytical models will provide theoretical guidance for maintaining the reliability and integrity of in-service pressurised pipelines. [ABSTRACT FROM AUTHOR]

Aortic aneurysm (AA) is a serious condition that largely increases the risk of aortic dissection and sudden death. Exploring the global burden of disease and changes in risk factors for AA is essential for public health policy development. To project the death burden from AA and its attributable risk factors in the following decade based on the epidemiological data over the past 30 years. We analysed the death burden of AA and trends of four risk factors from 1990–2019 using the updated 2019 Global Burden of Disease study database by Joinpoint regression analysis. Furthermore, we project the AA-related death burden for the next decade using the Bayesian age-period-cohort model. This study discovered that the global burden of death attributable to AA began to increase after decreasing for two decades. This upward trend will continue in the subsequent decade (average annual percent change: 0.318%, 95% CI: 0.288 to 0.348). Meanwhile, the disease burdens in all economic regions except high-middle socio-demographic index (SDI) regions will continuously increase in the next decade, with the fastest acceleration in the low-middle SDI region (average annual percent change: 1.183%, 95% CI: 1.166 to 1.200). Notably, high systolic blood pressure will surpass the contribution of smoking to become the most important risk factor for mortality due to AA. This study discovered a rebounding trend in the aortic aneurysm-related death burden globally. High systolic blood pressure will be the top risk factor attributed to death from AA. Therefore, it should be considered as the first-degree risk factor in the guidance of AA management and criteria for population-based screening programs. The death burden of aortic aneurysms is beginning to rebound globally, and the trend will continue for the next decade. High systolic blood pressure will replace smoking as the most important risk factor associated with aortic aneurysm death. [ABSTRACT FROM AUTHOR]

Background: To develop a sensitive and clinically applicable risk assessment tool identifying coronavirus disease 2019 (COVID-19) patients with a high risk of mortality at hospital admission. This model would assist frontline clinicians in optimizing medical treatment with limited resources.Methods: 6415 patients from seven hospitals in Wuhan city were assigned to the training and testing cohorts. A total of 6351 patients from another three hospitals in Wuhan, 2169 patients from outside of Wuhan, and 553 patients from Milan, Italy were assigned to three independent validation cohorts. A total of 64 candidate clinical variables at hospital admission were analyzed by random forest and least absolute shrinkage and selection operator (LASSO) analyses.Results: Eight factors, namely, Oxygen saturation, blood Urea nitrogen, Respiratory rate, admission before the date the national Maximum number of daily new cases was reached, Age, Procalcitonin, C-reactive protein (CRP), and absolute Neutrophil counts, were identified as having significant associations with mortality in COVID-19 patients. A composite score based on these eight risk factors, termed the OURMAPCN-score, predicted the risk of mortality among the COVID-19 patients, with a C-statistic of 0.92 (95% confidence interval [CI] 0.90-0.93). The hazard ratio for all-cause mortality between patients with OURMAPCN-score >11 compared with those with scores ≤ 11 was 18.18 (95% CI 13.93-23.71; p < .0001). The predictive performance, specificity, and sensitivity of the score were validated in three independent cohorts.Conclusions: The OURMAPCN score is a risk assessment tool to determine the mortality rate in COVID-19 patients based on a limited number of baseline parameters. This tool can assist physicians in optimizing the clinical management of COVID-19 patients with limited hospital resources. [ABSTRACT FROM AUTHOR]

Traditional Light Detection and Rangings (LiDARs) can quickly collect high-accuracy of three-dimensional (3D) point cloud data at a designated wavelength (i.e., cannot obtain hyperspectral data), while the passive hyperspectral imager can collect rich spectral data of ground objects, but are lack of 3D spatial data. This paper presents one innovative study on the design of airborne-oriented supercontinuum laser hyperspectral (SCLaHS) LiDAR with 50 bands covering 400 nm to 900 nm at a spectral resolution of 10 nm and ground sampling distance (GSD) of 0.5 m. The major innovations include (1) development of the high-power narrow-pulse supercontinuum laser source covering 400 nm to 900 nm with 50 bands using multi-core microstructure fibre, all-polarization maintaining fibre and ultra-long cavity structure, (2) a miniaturized aberration correction holographic concave grating spectroscopic and streak tube technique are developed for 50 bands laser echoes detection at high spectral-spatial-temporal resolution and dynamic airborne platform, and (3) the algorithm theoretic basis for SCLaHS LiDAR point cloud data 3D geodetic coordination calculation, including in-flight airborne calibration algorithm. The initial experimental results demonstrated that the designed SCLaHS LiDAR is doable, and a prototype of the (SCLaHS) LiDAR intends to be implemented. [ABSTRACT FROM AUTHOR]

Fossils of Auroraceratops are abundant and found in high concentrations within the Mazongshan area of northwestern China. As small basal Neoceratopsia discovered from the Lower Cretaceous, its general anatomy is well known; however, the endocranial morphology of this genus has never been formally described before. Here, we selected a well-preserved skull which belongs to Auroraceratops sp. and used a high-resolution CT scan to reconstruct its three-dimensional, virtual endocast in order to illustrate the endocranial structures in detail. Our study provides the first description of the endocranial anatomy of Auroraceratops and compares it with other relevant ceratopsian taxa. Our result shows that for a basal Neoceratopsia, the endocranial morphology of Auroraceratops is closer to that of non-neoceratopsian ceratopsian Psittacosaurus than the more derived neoceratopsians, such as Pachyrhinosaurus, which provides new insight into the endocranial characters of basal Neoceratopsia. [ABSTRACT FROM AUTHOR]

An imaging system is designed with a liquid crystal (LC) lens as the focusing element. The aperture of the LC lens plays the role of the aperture stop of the system. An entrance pupil larger than the LC lens aperture is realized and the magnification of the image formed by the system remains unchanged when the focal length of the LC lens is changed by the applied voltages. [ABSTRACT FROM AUTHOR]

Cedrus deodara is a cedar plant from the Pinaceae family. Because Cedrus is widely used in health care products, cosmetics, medicine, and insecticides, the essential oils of Cedrus deodara (CDEOs) are gaining increasing levels of attention. However, there have only been a few studies on the anti-inflammatory effects of CDEOs. This study aimed to systematically study the composition and biological effects of CDEOs, in line with this, the study assessed the chemical composition of CDEOs and evaluated their anti-inflammatory mechanisms in mice. Gas chromatography-mass spectrometry (GC-MS) was used to determine and analyze a total of 41 compounds from CDEOs. It was found that the major components of CDEOs are thujopsene (28.23%), α-cedrene (17.01%), and cedrol (15.55%); moreover, our results showed that the active ingredients in CDEOs have anti-inflammatory and antioxidant effects and that the active ingredients in CDEOs can be used as an antioxidant, as an important biological resource in functional food, and as ingredients in cosmetics and pharmaceuticals. Taken together, these CDEOs serve as ideal additives for anti-inflammatory drugs. [ABSTRACT FROM AUTHOR]

Semicontinuous variable analysis is a widely appreciated statistical method in such disciplines as social science, medicines, and economics. In detecting underlying structure and representing possible interrelationships, statistical analysis using a two-part model is appropriated. In this paper, we present a general extension of two-part model to the situation where the unobserved factors are included in the two parts to interpret external variability in semicontinuous variable. Auxiliary information on these factors is manifested by continuous responses via measurement model, while the interrelationships among factors are exploited through structural equation model. Moreover, under longitudinal setting, dynamic characteristics of responses between any two occasions are represented by transition model. Procedures for model fitting, parameter estimation, model selection and prediction are developed within the Bayesian paradigm. Markov Chains Monte Carlo method is used to implement posterior analysis. Empirical results including a simulation and a real example are used to illustrate the proposed methodology. [ABSTRACT FROM AUTHOR]

Objectives. Stroke is a common condition after a transient ischemic attack (TIA) or minor ischemic stroke (IS). Adding clopidogrel to aspirin may yield more beneficial outcomes than aspirin mono-therapy; meanwhile, the risk of bleeding in the acute phase remains poorly understood. Therefore, there is increasing emphasis on the risks and benefits of clopidogrel with aspirin compared with aspirin mono-therapy in an effort to treat TIA/IS. Design. We searched several electronic databases, including PubMed, Cochrane, and Embase, to identify eligible randomized controlled trials (RCTs) based on the index words comparing dual-antiplatelet therapy to aspirin mono-therapy for secondary stroke prevention updated to December, 2018. Results. A total of 11 RCTs met our inclusion criteria. The pooled analysis showed that clopidogrel plus aspirin was associated with a trend toward a reduction in recurrent IS (RR = 0.72, 95%CI = 0.65-0.81, p < .001), but not the recurrent stroke rate (RR = 0.81, 95% CI = 0.63-1.03, p = .09) than aspirin mono-therapy. There were differences in bleeding episodes (RR = 1.81, 95%CI = 1.65-1.99, p < .001), moderate-severe major bleeding (RR = 1.64, 95% CI = 1.24-2.16, p = .0005), or mild bleeding (RR = 2.25, 95%CI = 1.54-3.31, p < .001) between the study groups. Meanwhile, no benefit of reducing the risk of intracranial hemorrhage with dual-antiplatelet therapy was found in TIA/IS patients (RR = 1.44, 95% CI = 0.95-2.19, p = .09). Conclusions. The addition of clopidogrel to aspirin for patients with TIA or IS appeared to significantly reduce the risk of IS recurrence with a possible increase in the risk of bleeding compared with aspirin alone. [ABSTRACT FROM AUTHOR]

This exploratory research investigates the nature of explanation use and factors that influence it during users' interaction with a knowledge-based system (KBS) for decision-making. It draws upon several cognitive perspectives to help understand when, why, and how explanations are used. A verbal protocol analysis was conducted based on a laboratory experiment involving a KBS for financial analysis. Major categories of explanation use were identified, and accounted for with relevant cognitive perspectives. Results show that explanations were requested to deal with comprehension difficulties caused by various types of perceived anomalies in KBS output. There were qualitative and quantitative differences in the nature and extent of explanation use between novices and experienced professionals. These results offer new insights to why explanations are useful and important, what factors influence explanation use, and what information should be included in explanations. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the effect of decomposing Cinnamomum septentrionale leaf litter on the growth of maize. In this study, the morphological traits of maize were significantly inhibited when the leaf litter amount reached or exceeded 40 g per pot; Furthermore, during the early growth stage or with a large amount of litter addition, the pigment contents were inhibited by C. septentrionale leaf litter. Gas chromatography–mass spectrometry was used to determine the volatile substances of leaf litter and 34 compounds were identified, several of which were reported to be phytotoxic. In conclusion, the leaf litter of C. septentrionale showed a strong allelopathic effect on the growth of maize. Thus, it is better to avoid the growing of maize under or near the C. septentrionale plantation unless the leaf litter could be eliminated in time or other effective leaf litter processing methods could be implemented. [ABSTRACT FROM AUTHOR]

In order to solve the limitations of the hydrodynamic performance of traditional ship-type and cylindrical FDPSO (floating, drilling, production, storage and offloading unit), this paper proposes a new concept of sandglass-type FDPSO. For the new floating model, by using classic boundary element method, the characteristic of its heave motion response can be studied. Then based on the wave potential theory, engineering estimation expressions of heave motion performance are theoretically and mathematically deduced to summarise the design guidelines and schemes for sandglass-type floating body. Furthermore, according to the information of a ship-type FDPSO named as MPF, a sandglass-type floating body of new FDPSO with the same basic function has been designed. Finally, compared with ship-type, cylindrical and semi-submersible floating body, the design guideline in this paper can be validated to be effective and rational. New sandglass-type design can significantly improve the hydrodynamic performance of FDPSO. Therefore this paper can provide an innovative engineering platform and design proposal for the development of deep-water oil and gas. [ABSTRACT FROM AUTHOR]

It is of significant importance to monitor the attitude of ship during navigation and operations. The three uppermost parameters of the attitude monitoring are roll, pitch and heave. For measuring the above parameters accurately, a sensor is designed in this paper. First, the attitude algorithm of this sensor is learned. A modified Rodrigues parametrisation-based method is developed in solving the attitude algorithm and extended Kalman filter algorithm is used to achieve the optimal value. The sensor calibration model was studied too. Second, in order to observe and measure the results more conveniently and intuitively, a user-friendly monitoring system is developed. Due to the development of the corresponding analysis system, the measured results can be analysed for a better understanding of the characteristics of the ship. Specially, the ship command parameters are as the input of the sensor and the corresponding closed-loop measure, and control system is designed to solve the problem that the current study cannot eliminate the effects of the attitude measurement inaccuracy of the sensor very well owing to the ship's acceleration. The control strategy is verified by the sea trials because the attitude measurement error caused by the ship's acceleration is significantly reduced. The accuracy of the designed attitude sensor is also verified. More importantly, the application prospects of the designed are also illustrated in this paper. [ABSTRACT FROM AUTHOR]

An active truncation hybrid model test is regarded as the most effective way for deep-water flexible structure test by The International Towing Tank Conference (ITTC). Owing to environmental loads and the movement of vessel, the dynamic boundary conditions at the truncated position related to the active truncation method are hard to be controlled. It has little relevant research which is reported on this testing technology. In this paper, an active truncation method is performed to simulate the process of deep-water steel catenary riser installation. The mechanical model of steel catenary riser (SCR) installation process is developed and corresponding equations for the developed model are derived. At the truncated position, device control principles are fitted from the solutions of the derived equations. 6-DOF (degrees of freedom) platform is used to simulate the motions of vessel. And the software and hardware of control system for this active truncation method are developed. The concept is first proposed, of which, that deep-water steel catenary riser installation test is conducted onshore. The test results show that this active truncation method is capable to simulate the process of steel catenary riser installation well. The test method has also provided the foundation for future works of other deep-water projects. [ABSTRACT FROM PUBLISHER]

Because of long-term drying of the lower reaches of the Tarim River, oasis ecosystems are facing serious threats and have started to degenerate. An ecological water conveyance project has been started in the lower reaches of the Tarim River to save the degenerated ecosystem. The effects of ecological water conveyance on the ring width increments of Populus euphratica were studied by use of the trend analysis method, the moving t test technique, and a regression equation based on ring increment data from the past 40 years in the lower reaches of the Tarim River. Results showed that the ring increments of Populus euphratica in four monitoring transects along the river can be divided into two parts, 1970-2001 and 2002-2008. This division implies that ecological water conveyance had a positive effect on the increase of ring increments. The ring increments of Populus euphratica in Yinsu, Kardayii, Alagan, and Yiganbjma increased by 79.37, 174.5, 75.61, and 71.81% after ecological water conveyance. The years 2002, 2001, 2001, and 2002 were the transition years in the Yinsu, Alagan, Kardayi, and Yiganbjma transects, respectively. The ring width increments in Yinsu, Kardayi, Alagan, and Yiganbjma as a result of ecological water conveyance were 1.41, 0.987, 0.265, and 0.671 mm, respectively. The main cause of the changes in ring width increments was the rise of groundwater level. The results from this study should contribute to improved management of the ecosystems in the lower reaches of the Tarim River, and can also provide a scientific basis for implementing similar projects in other arid and semiarid areas. [ABSTRACT FROM AUTHOR]

Structural equation models have wide applications. One of the most important issues in analyzing structural equation models is model comparison. This article proposes a Bayesian model comparison statistic, namely the Lν-measure for both semiparametric and parametric structural equation models. For illustration purposes, we consider a Bayesian semiparametric approach for estimation and model comparison in the context of structural equation models with fixed covariates. A finite dimensional Dirichlet process is used to model the crucial latent variables, and a blocked Gibbs sampler is implemented for estimation. Empirical performance of the Lν-measure is evaluated through a simulation study. Results obtained indicate that the Lν-measure, which additionally requires very minor computational effort, gives satisfactory performance. Moreover, the methodologies are demonstrated through an example with a real data set on kidney disease. Finally, the application of the Lν-measure to Bayesian semiparametric nonlinear structural equation models is outlined. [ABSTRACT FROM AUTHOR]

We numerically calculate dynamical behaviors of the molecular reorientation of liquid crystal (LC) directors and of the phase retardation in an LC optical device with eight-divided circularly hole-patterned electrode and external transparent electrode. The three-dimensional (3D) distributions of the elliptical phase retardation in the hole-patterned aperture can be obtained by adjusting the applied voltage to each electrode. The transient properties of the phase profile can be estimated and be predicted fairly well by the numerical calculation. [ABSTRACT FROM AUTHOR]

We propose a laser manipulator for controlling positions and rotation of trapped microscopic particles suspended in water by using a liquid crystal (LC) device. This LC device has unique functions such as an anamorphic lens property, variable-focusing and deflection properties. The trapped slender particle can be aligned along the major axis of the elliptically shaped laser beam spot and the position of the particle can be controlled. Furthermore, the positions of multiple microscopic particles can also be controlled along the interference fringe patterns of a wedge LC cell. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to investigate the expression and regulation of cytoskeleton and apoptosis related genes in several brain areas after cerebral infarction. Methods: Tissues were collected from ten autopsy brains from cerebral infarction patients. Using immunohistochemistry, several cytoskeleton and apoptosis related genes were examined in these tissues. The genes included microtubule-associated protein (MAP), glial fibrillary acidic protein (GFAP), neurofilament protein (NF-200), apoptosis gene bc1-2 and factor VIII related antigen (F-VIII). Based on morphological changes in the damaged areas after infarction, the focus and the surrounding areas of injured brain were divided into four areas. Results: In area 0, there was almost no cell survival after infraction, and all markers mentioned above were negative in this area. In addition, both MAP-2 and NF200 like immunoreactivities were dramatically down-regulated in area 1. However, in area 2 and area 3, MAP-2 and NF-200 expressed at normal level. GFAP- and F-VIII immunoreactive cells could hardly found in areas 0 and 1. In the short phase of ischemia, both GFAP and F-immmunoreactive cells could be seen in areas 2 and 3, and the number of GFAP and F (positive cells) was strongly increased in the long phase of ischemia. Bcl-2 immunoreactive cells were only seen in area 2. Conclusion: Cerebral infarction causes cell death and physipathological changes of cytoskeleton and apoptosis related genes. [ABSTRACT FROM AUTHOR]

Liquid crystal lenses(LCL)of two liquid crystal(LC)layers with parallel and orthogonal optic axes are built. The LCL of two LC layers with parallel optic axes is designed to obtain larger focusing power, and that with orthogonal optic axes is to focus light wave of arbitrary polarizations. The focal lengths of both LCLs can be controlled by external voltages. [ABSTRACT FROM AUTHOR]