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Modern trams have been widely used around the world, especially in China. This paper explores the main influencing factors of modern trams' passenger flow at the early operational stage. The system dynamics model is adopted for dealing with the problem on hand. Tram Line 1 in Huai'an, Jiangsu Province, China is selected as the case study. Data are collected using the RP and SP survey. The sensitivity test and extreme condition test are performed. The simulation results demonstrate that four variables (i.e., land development intensity, fares, service level, and transfer efficiency) significantly affect passenger flow. Land development intensity is the most significant factor, and the effect of service level on passenger flow is higher than that of the fares. The departure interval of 10 minutes is the maximum psychological limit that passengers can bear, and 2 RMB is a reasonable price. Such conclusions can provide guidance for the planning and design of modern trams and address the problem of shortage of passengers at an early stage. [ABSTRACT FROM AUTHOR]

Water resources efficient utilization is the key to ecological improvement and economic development in Tarim River Basin. It is necessary to analyze the water resources utilization and its variation tendency in the whole river basin. Based on the monitored data and formation at eight meteorological stations and fifteen hydrological stations, the method of time series, regression analysis are applied to analyzing the water resources utilization and variation trend in the headstreams and mainstream areas especially in recent 10 years . The quantitative results indicate that inflows of the headstream areas have an increasing trend to different extent in the past 40 years. The runoff increasing trend is more significant from 1994 to 2002, which show the water resources condition in the headstreams is at an advantage. However, under the condition of water increase with the volume of 25×108 m³ in headstreams in recent 10 years, the mainstream water flowing from the headstreams has increased less than 0.9985×108 m³. In addition, the runoff at the different hydrologic stations along the Tarim River has a significant linear decreasing trend. It is shown that the degraded trend of ecological environment in the mainstream areas hardly changes even if the Tarim River Basin is in the special water period for ten consecutive years. [ABSTRACT FROM AUTHOR]

Aim: Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease and also closely related to cardiometabolic disease. Its prevalence was estimated at over one-fourth in the general population in China. We aimed to develop effective score tools for detecting NAFLD.Methods: A total of 17,212 participants aged 45-70 years old were surveyed in Shanghai between 2013 and 2014, and 13,293 participants were included in this analysis. All participants were randomly classified into the exploratory group or the validation group. Candidate categorical variables were selected using a logistic regression model. The score points were generated according to the β-coefficients.Results: We developed the Shanghai Nicheng NAFLD Score I (SHNC NAFLD Score I), which included body mass index and waist circumference with an area under the receiver-operating characteristic curve (AUC) of 0.802 (95% CI 0.792-0.811) in the exploratory group and 0.802 (95% CI 0.793-0.812) in the validation group. We further developed the SHNC NAFLD Score II by adding fasting plasma glucose, triglyceride, and alanine aminotransferase/aspartate aminotransferase ratio to the SHNC NAFLD Score I, achieving an AUC of 0.852 (95% CI 0.843-0.861) in the exploratory group and 0.843 (95% CI 0.834-0.852) in the validation group. The two score tools also performed well in subjects with normal alanine aminotransferase (ALT) levels.Conclusions: Based on anthropometric and clinical categorical variables, our two scores are effective tools for detecting NAFLD in both this southern Chinese population and their subpopulation with normal ALT levels. [ABSTRACT FROM AUTHOR]

Light olefins including ethylene and propylene are important chemical materials, and a diversity of production technologies have been applied in industrial processes. An index called Olefins Production Security Index (OPSI) is proposed for quantifying the performance of techno-economics and security for different olefins production routes. The results show that Coal via Methanol to Olefins (CMTO) and Coal via Methanol to Propylene (CMTP) routes have the higher security rank in terms of raw materials supply and reasonably good economic performance compared with the Nature Gas via Fischer–Tropsch Synthesis to Olefins (NFTO) and Deep Catalytic Cracking (DCC) routes. Carbon Dioxide via Methanol to Olefins (CDMTO) and Carbon Dioxide via Methanol to Propylene (CDMTP) routes have lower carbon dioxide emissions but higher direct production costs. Basically, CMTO, CMTP, and Nature Gas via Methanol to Olefins (NMTO) routes have the top OPSI grades, which means they are more competitive than other routes in terms of security. We also identify the shortcomings of each olefins production route with regard to the security through sensitivity analysis. It is expected the proposed framework plays a role in searching the most suitable production route for light olefins from the viewpoint of security. [Display omitted] • Light olefins production routes are evaluated against techno-economics and security. • Olefins Production Security Index (OPSI) is proposed. • OPSI considers effects of raw materials, energy, technology, economy, and CO 2. • OPSI can be genetically extended to other industrial productions chain. [ABSTRACT FROM AUTHOR]

Themethanol to olefins (MTO) process has been successfully commercializedin China and will potentially become an important route for lightolefins production. In this work, a modeling approach is presentedfor MTO fluidized bed reactor design and operation optimization. Thetwo-fluid model (TFM) where the solid phase shear viscosity and solidphase pressure are derived from kinetic theory of granular flow hasbeen used to model the solid–gas two-phase flows. The interphasedrag force is calculated by either the traditional Gidaspow modelor a recently developed EMMS-bubble model. The simulation study hasbeen performed for a fluidized bed reactor in a 16 kt/a DMTO unit.It has been shown that the Gidaspow model cannot predict a stabledense bed, while the EMMS-bubbling model could simulate the solidfraction distribution in the reactor reasonable well. A reaction modelbased on the simple MTO reaction kinetics has been implemented totest the effectiveness of the model approach. The simulation resultsshow that the methanol is converted rapidly just above the gas inlet.The selectivity of ethylene and propylene however are underpredicted,while the selectivity of CO2and other products are overestimated.It is suggested that a further extension of the EMMS model to a turbulentfluidized bed is important in order to get more quantitative results.Also the MTO reaction kinetics for a commercial DMTO catalyst, inwhich the coke formation kinetics should be included, is highly desired. [ABSTRACT FROM AUTHOR]

Background: To investigate the effect of extubation in the operating room (OR) on mechanical ventilation-related adverse outcomes in patients who undergo liver transplantation. Methods: Patients who underwent liver transplantation between January 2016 and December 2019 were included. According to the timing of extubation, patients were divided into OR extubation group and intensive care unit (ICU) extubation group. The propensity score was used to match OR extubation group and ICU extubation group at a 1:2 ratio by demographical and clinical covariates. The primary outcome was a composite of mechanical ventilation-related adverse outcomes, including 30-day all-cause mortality, in-hospital acute kidney injury (stage 2 or 3), and in-hospital moderate to severe pulmonary complications. Secondary outcomes included in-hospital moderate to severe infectious complications, unplanned reintubation rates, ICU and postoperative hospital lengths of stay, and total hospital cost. Results: A total of 438 patients were enrolled. After propensity score matching, 94 patients were in OR extubation group and 148 patients were in ICU extubation group. Incidence of the composite mechanical ventilation-related adverse outcomes was significantly lower in OR extubation group than ICU extubation group, even after adjusting for confounding factors (19.1% vs. 31.8%; Odds Ratio, 0.509; 95% Confidence Index [CI], 0.274-0.946; P=0.031). The duration of ICU stay was much shorter in OR extubation group than ICU extubation group (median 4, Interquartile range [IQR] (3 ~ 6) vs. median 6, IQR (4 ~ 8); P<0.001). Meanwhile, extubation in the OR led to a significant reduction of total hospital cost compared with extubation in the ICU (median 3.9, IQR (3.5 ~ 4.6) 10000 US dollars vs. median 4.1, IQR (3.8 ~ 5.1) 10000 US dollars; P=0.021). However, there were no statistically significant differences in moderate to severe infectious complications, unplanned reintubation rates, and the length of postoperative hospital stay between groups. Conclusions: Among patients who underwent liver transplantation, extubation in the OR compared with extubation in the ICU, significantly reduced the primary composite outcome of 30-day all-cause mortality, in-hospital acute kidney injury (stage 2 or 3), or in-hospital moderate to severe pulmonary complications. Trial registration: The trial was registered at www.clinicaltrials.gov with registration number NCT04261816. Retrospectively registered on 1st February 2020. [ABSTRACT FROM AUTHOR]

China's lunar exploration program has developed and progressed for more than 13 years. Over this time, Precise Orbit Determination (POD) has guaranteed successful execution of the Chang'e missions, and is the basis for further scientific investigations using radio science data; for example, recovering the lunar gravity field to explore the inner structure and detect craters to study the evolutionary history of the moon. This study briefly reviews the Chang'e series mission orbit and radio tracking measurements. We reprocessed the tracking data and comprehensively summarized the evolution of the POD accuracy and the tracking system precision from the Chang'e 1 to Chang'e 4 missions using in‐house software. Our results show a progression of the tracking station, as the first Chang'e 1 mission only reached several millimeters per second level accuracy in the Doppler measurements and several meters level accuracy for the two‐way range measurements. Later on the accuracy of Chang'e 5T1 Doppler measurements reached about 0.35 mm/s and the accuracy of the Chang'e 3 two‐way range measurements below 0.7 m. Moreover, the newest Chang'e 4 relay satellite achieved POD residuals Root Mean Square for the two‐way range less than a meter and orbital accuracy at 200 m level, in contrast to meters level residual and the half‐kilometer level accuracy achieved during the Chang'e 1 mission. We can clearly see that the POD performance of the Chang'e spacecraft continuously improved. This research study is a reference for future Chinese Lunar exploration missions, as well as Chinese Mars and asteroid explorations. Key Points: We first summarized orbital geometry, tracking network and its tracking strategies of all Chang'e missionsWe have processed the tracking data on the orbiting phase, from Chang'e 1 to Chang'e 4, and concluded its orbit accuracyMoreover, we also displayed some puzzling points which happened in Chang'e 1 and 2 missions in tracking data and answered them [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]

China's unique energy reserve structure abundant in coal and scarce in crude oil and natural gas has promoted heavy investment on the research and development of clean coal chemical technologies during last two decades, which has turned China into a heartland for demonstrating, developing, and commercializing virtually every aspect of new coal chemical process technologies. Consequently, breakthroughs in coal gasification, indirect and direct coal-to-liquid (CTL) processes, and methanol-to-olefins (MTO) technologies are catching attention worldwide. Gasification technology for syngas production is the key to high plant availability and economic success for most coal chemical projects. During the past 20 years, both international and Chinese gasifier vendors have reaped great successes in licensing their technologies in the domestic market. Notably, the local vendors have been investing heavily on inventing and improving their technologies to suit the specific requirement of gasifying a variety of coals. The opposed multinozzle gasification technology from East China University of Science and Technology was taken as an example to demonstrate the recent development in this field. The coal chemical industry in China has witnessed several notable achievements in chemical engineering progress, namely CTL (indirect and direct) and MTO. Comprehensive reviews on topics such as catalysis, kinetics, and reactor design and process integration will be provided by leading scientists in related fields with firsthand information to showcase the contributions of Chinese researchers to chemical engineering science and technology. [ABSTRACT FROM AUTHOR]

Insulin resistance (IR) is closely associated with cardio-metabolic diseases. However, the impact of IR on bone mass remains obscure. The present study is to evaluate the association between the triglyceride-glucose (TyG) indicated IR and bone mass in a nationwide health check-up population in China. We conducted a retrospective cross-sectional study including 788,247 participants and a longitudinal cohort study in 8770 participants who had repeated measurements of TyG index and bone mass in at least a 2-year follow-up period. The restricted cubic splines and logistic models were used to analyze the association between IR and bone mass in the cross-sectional study. The Cox model was applied to evaluate the relationship between baseline IR and the subsequent incidence of low bone mass and osteoporosis in the longitudinal study. In the cross-sectional study, the TyG index had positive correlations with low bone mass, osteoporosis, or both after adjusting for confounding factors (all P < 0.001). In the longitudinal cohort study, the baseline TyG index was significantly associated with the incidence of low bone mass, osteoporosis, or both during the follow-up period, with hazard ratios (HRs) of 1.56 (95 % confidence interval [CI]: 1.25, 1.93, P < 0.05), 1.66 (95%CI: 1.06, 2.59, P < 0.05), and 1.55 (95%CI: 1.27, 1.88, P < 0.05) after adjusting for confounding factors, respectively. These results suggest that IR indicated by TyG is significantly associated with an increased risk of low bone mass and osteoporosis. Therefore, bone mass monitoring and early prevention strategies may be needed in individuals with IR to prevent the occurrence of low bone mass and osteoporosis. • The association between insulin resistance (IR) and bone mass remains unclear. • A cross-sectional study (n = 788,247) and a longitudinal study (n = 8,770) were conducted. • TyG-indicated IR is associated with an increased risk of low bone mass and osteoporosis. • BMD monitoring and early prevention may be helpful for populations with IR. [ABSTRACT FROM AUTHOR]

Microbial community assembly contributes to the restoration and rehabilitation of the disturbed ecosystems. However, the viral assembly mechanism and its difference from bacterial communities under soil contamination have not been previously reported. Here, clean, light and heavy chromium (Cr)-contaminated soils were collected from two Cr slag sites and adjacent soils in northwestern and southwestern China. Through metagenome and virome sequencing analysis, we found that the alpha diversity of bacterial genes (including overall genes and Cr detoxifying genes) showed no clear variance (p > 0.05) across soils, indicating the functional redundancy in the bacterial communities. The assembly of both the bacteria and virus taxa were primarily controlled by deterministic process across soils The assembly of bacterial genes turned from stochastic processes to deterministic processes when the Cr content increased in soils. By contrast, the assembly of viral genes altered from deterministic processes in clean soil into stochastic processes in Cr-contaminated soils. Virus-host linkage results showed that the niche breadth of bacteria and viruses was closely related. The normalized stochasticity ratio of viral functional assembly was positively correlated with the Simpson index of the bacteria (p < 0.05). The results suggested that the stochasticity of viral functional assembly was conducive to facilitating the functional redundancy of bacterial communities and their evolution toward the deterministic direction. [Display omitted] • Bacteria maintained functional redundancy under Cr exposure. • Deterministic process dominated the assemblies of bacterial and viral taxa. • Bacterial and viral genes were driven by distinct processes due to Cr exposure. • Viral communities facilitated the functional redundancy of host bacteria. [ABSTRACT FROM AUTHOR]

Yanshanian magmatism develops well and has obvious metallogenic specificity in the Qinzhou–Hangzhou bays of South China. Zircon, in granite, has great potential in the study of metallogenic specificity. Moreover, with the development of in-situ zircon analysis technology, a significant amount of data on zircon composition has become available in recent years. Hence, to further elucidate the distinctive diagnostic signatures of zircon signatures regarding metallogenic fertility and the preference for metallogenic types of granites, this paper exhaustively explores all possible bivariate and ternary discrimination diagrams using a set of 13 rare-earth elements with published zircon data from Yanshanian, South China. This results in 4095 binary diagrams and 12,485 ternary diagrams, ranked according to their success in classifying the training data. One-hundred binary graphs and 300 ternary graphs with the highest CH index values were selected, from which the graphs were picked out. The results reveal that there is no suitable diagram to distinguish between mineralization and barren granites. Further, in the diagrams to distinguish the type of mineralization, there are indeed some overlapping parameter ranges (such as Gd/Yb and Ce/Gd); however, it still can be observed that some binary and ternary graphs containing Eu or Ce (e.g. Eu/Gd, Eu/Tb and Ce/Sm) can discriminate between samples related to porphyry Cu and samples related to W–Sn (Sn). Some diagrams (i.e. Dy/Lu–Er/Lu, Gd/Dy–Er/Yb) also have been observed to distinguish between ore-forming types of granites, the underlying geochemical mechanism of which has not been fully understood. In addition, our results suggest that the linear discrimination analysis (LDA) method outperforms any of the traditional discrimination diagrams in discriminating ore-bearing and fertile granites. The results of geochemical data mining in this paper can be used as prospective indicators to provide a scientific basis for the study of Yanshanian hydrothermal deposits in South China. Moreover, the compositions of zircon are relatively simple to obtain, and the LDA methods described in this study could potentially be used as a useful exploration tool. • New discrimination diagrams were proposed by using zircon REE composition. • Most discrimination diagrams related to Eu and Ce can distinguish the mineralization information of the parent rock. • The linear discrimination analysis (LDA) method remarkably outperforms any traditional discrimination diagram. [ABSTRACT FROM AUTHOR]