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Nitrogen-doped porous carbon (NPC) has a rich microporous structure and nitrogen-rich units, and its nitrogen-containing group can interact strongly with the PEO chain segment of Pebax, synergistically improving its CO2 adsorption ability and interface compatibility. This work prepared three types of triazine-based NPCs with mesoporous and high N-content and added NPCs to Pebax-2533 to prepare NPC/Pebax-2533 MMMs. The effects of N-type, N-content, and pore structure of NPCs on the gas separation performance of MMMs were studied. Constructing a continuous meso-microporous structure within the membrane and adding alkaline N-containing groups were beneficial for promoting rapid CO2 transport. Among the three NPCs, NPC-1/Pebax MMMs prepared using NPC-1 with the highest N-content (10.91%) and suitable pore structure exhibited the best gas separation performance. To investigate the gas transport mechanism of NPC in MMMs, NPC-1 was added to Pebax-2533 and Pebax-1657. The permeability of 3NPC-1/Pebax-2533 MMMs and 0.5NPC-1/Pebax-1657 MMMs reached 423 Barrer and 178 Barrer, with a CO2/N2 selectivity of 61 and 75.8, respectively, both higher than the Pebax-2533 and Pebax-1657. Adding NPC-1 to Pebax-2533 and Pebax-1657 increased the solubility and diffusivity coefficient of MMMs by 40 ~ 80%, and the gas separation performance did not rapidly decrease after long-term stability of 120 h (15%CO2/N2). Compared with NPC-1/Pebax-1657 MMMs, NPC-1/Pebax-2533 MMMs had higher CO2 permeability, mechanical properties, solubility, and diffusivity coefficient. The above results indicated that NPC was more suitable for Pebax-2533. [ABSTRACT FROM AUTHOR]

Fe–Si3N4 was introduced to improve the service performance of corundum‐based dry vibratable refractories in the casting industry, specifically enhancing their thermal shock resistance and resistance to slag corrosion. The study analyzed the effects of Fe–Si3N4 powder content on the refractories' mechanical properties, phase compositions, slag corrosion resistance, and microstructures. The addition of Fe–Si3N4 facilitated the production of magnesium aluminate spinel in the refractory matrix, while also decreasing the wettability between the molten slag and refractory. Increasing the Fe–Si3N4 content resulted in accelerating the replacing Mg2+ (0.072 nm) with Al3+ (0.053 nm) in the spinel. Simultaneously, Fe3+ (0.055 nm) was effectively dissolved into the alumina crystals. The bulk density, compressive strength, and slag corrosion resistance of the refractories were improved. However, the thermal shock resistance initially increased but then decreased. In industrial tests, a corundum‐based dry vibratable refractory with a 1 wt.% Fe–Si3N4 content effectively prolonged the lifespan of an induction melting furnace when used as a lining refractory. Importantly, the refractory did not spall or generate cracks in the matrix after induction melt furnace industrial test. [ABSTRACT FROM AUTHOR]

The construction industry is accident-prone, and unsafe behaviors of construction workers have been identified as a leading cause of accidents. One important countermeasure to prevent accidents is monitoring and managing those unsafe behaviors. The most popular way of detecting and identifying workers' unsafe behaviors is the computer vision-based intelligent monitoring system. However, most of the existing research or products focused only on the workers' behaviors (i.e., motions) recognition, limited studies considered the interaction between man-machine, man-material or man-environments. Those interactions are very important for judging whether the workers' behaviors are safe or not, from the standpoint of safety management. This study aims to develop a new method of identifying construction workers' unsafe behaviors, i.e., unsafe interaction between man-machine/material, based on ST-GCN (Spatial Temporal Graph Convolutional Networks) and YOLO (You Only Look Once), which could provide more direct and valuable information for safety management. In this study, two trained YOLO-based models were, respectively, used to detect safety signs in the workplace, and objects that interacted with workers. Then, an ST-GCN model was trained to detect and identify workers' behaviors. Lastly, a decision algorithm was developed considering interactions between man-machine/material, based on YOLO and ST-GCN results. Results show good performance of the developed method, compared to only using ST-GCN, the accuracy was significantly improved from 51.79% to 85.71%, 61.61% to 99.11%, and 58.04% to 100.00%, respectively, in the identification of the following three kinds of behaviors, throwing (throwing hammer, throwing bottle), operating (turning on switch, putting bottle), and crossing (crossing railing and crossing obstacle). The findings of the study have some practical implications for safety management, especially workers' behavior monitoring and management. [ABSTRACT FROM AUTHOR]

Background: Daikenchuto (DKT) has positive therapeutic effects on improving various gastrointestinal disorders. The present study investigated whether or not DKT has a potential therapeutic effect on chemotherapy-induced acute small intestinal mucositis (CIM) in a rat model. Methods: Intraperitoneal injection of 10 mg/kg methotrexate (MTX) every 3 days for a total of 3 doses was used for induction of CIM in a rat model. The MTX and DKT-MTX groups were injected with MTX as above from the first day, and the DKT-MTX and DKT groups were administered 2.7% DKT via the diet at the same time. The rats were euthanized on day 15. Results: The DKT-MTX group showed an improvement in the body weight and conditions of gastrointestinal disorders as well as increased levels of diamine oxidase in plasma and in the small intestinal villi. The pathology results showed that small intestinal mucosal injury in the DKT-MTX group was less severe than that in the MTX group. Immunohistochemistry for myeloperoxidase and malondialdehyde and quantitative real-time polymerase chain reaction (RT-qPCR) for TGF-β1 and HIF-1α showed that DKT attenuated peroxidative damage. The crypts in the DKT-MTX group contained more Ki-67-positive cells than MTX group. The zonula occluden-1 and claudin-3 results showed that DKT promoted repair of the mucosal barrier. RT-qPCR for the amino acid transporters EAAT3 and BO+AT also confirmed that DKT promoted mucosal repair and thus promoted nutrient absorption. Conclusion: DKT protected against MTX-induced CIM in a rat model by reducing inflammation, stimulating cell proliferation, and stabilizing the mucosal barrier. [ABSTRACT FROM AUTHOR]

In this study, we successfully applied an external magnetic field for the first time in preparing oriented steel fiber reinforced mullite castable (OSFRMC). The impact of the castable's rheology, duration of exposure to the magnetic field and strength of the magnetic field on the orientation of steel fibers and the properties of the refractory castable was investigated. When the duration of exposure to the magnetic field was set at 60 seconds and the strength of the magnetic field was 2.5 mT, an orientation index of steel fibers in the refractory castable of 0.96 was achieved. This specific castable contained 6 wt% of microsilica. Moreover, the castable with a high orientation index (0.96) of steel fibers exhibited significant improvement in mechanical strength and thermal shock resistance compared to the untreated castable. In order to investigate the fracture behavior of steel fiber-reinforced refractory castables with different fiber orientations, a comparative study was conducted using force-displacement curves and digital image correlation techniques. The primary factor behind this improvement is the directional alignment of steel fibers, which enhances the bridging effect and crack deflection toughness within the material. • Optimization of castables' rheology was a key step to prepare the castables. • The orientation of steel fiber had a great influence on the properties of castables. • Magnetic field was applied to prepare the castable with oriented steel fibers. [ABSTRACT FROM AUTHOR]

As the global climate warms, carbon emissions must be reduced in order to alleviate the human climate crisis. Carbon capture, utilization and storage (CCUS) is an emerging technology that can reduce carbon emissions. However, most of the CCUS projects have ended in failure. The reason can be attributed to insufficient risk assessment. To this end, the purpose of this study is to construct a comprehensive risk assessment model for CCUS projects. The main body of this research is divided into two parts. First, in order to evaluate the CCUS project, a risk indicator system is constructed. In what follows, a decision-making framework for risk assessment under the D numbers environment is proposed, including two stages of decision-making preparation and decision-making process. The main task of the preparation stage is to gather evaluation experts and collect decision-making information. In the decision-making stage, this paper takes the D numbers theory as the core (acting on the effective expression and fusion of subjective evaluation information), respectively, proposes the method of determining the weight of risk evaluators, the fusion method of decision-making information from different experts, and the comprehensive decision model based on the MULTIMOORA method. In order to verify the effectiveness of the constructed model, the case of CCUS project site selection in Shengli power plant is analyzed, and the results showed that the third site is the best option. This study finds the importance of a comprehensive and timely risk assessment for the successful implementation of CCUS projects, and suggests that stakeholders carry out a risk assessment of CCUS projects prior to implementation based on the method presented in this paper, so as to improve the success rate. [ABSTRACT FROM AUTHOR]

The manufacturing of mullite porous ceramics with high strength and low thermal conductivity was achieved through foam gel-casting processes using fly ash coated with alumina sol layers. This research aimed to investigate the effect of alumina sol concentration on foaming slurry rheology, as well as the influence of alumina sol coating layers on the microstructure, phase compositions and properties of the resulting mullite porous ceramics. Increasing the alumina sol concentration from 5 to 20 wt% improved both the viscosity and thixotropy of the foaming slurries while enhanced the shear thinning behavior. Porous ceramics prepared with fly ash coated with alumina sol exhibited smaller pore size compared to the untreated fly ash porous ceramics. Moreover, the distribution of pores gradually became more homogenous in the porous ceramics with treated fly ash. Meanwhile, the weight-reduction, compressive strength and thermal insulation properties of the porous ceramics were improved significantly. The use of fly ash coated with alumina sol (with a concentration of 20 wt%) in the preparation of porous ceramics resulted in the formation of mullite whiskers within the pore walls. This created micron-size gaps between the whiskers, greatly enhancing the thermal insulation of the porous ceramics. Finally, the porous ceramics that were prepared using fly ash coated with alumina sol (with a concentration of 20 wt%) and sintered at a temperature of 1400 °C had a bulk density of 0.45 g/cm3, a compressive strength of 8 MPa, and a thermal conductivity of 0.15 W/m·k. • Fly ash coated with alumina sol for optimizes the rheology of foaming slurry. • Pore distribution became more homogenous in porous ceramics with treated fly ash. • Alumina sol layer can improve strength and thermal insulation of porous ceramics. [ABSTRACT FROM AUTHOR]

High energy, sub‐nanosecond, single longitudinal mode (SLM) pulse is especially preferred for LiDAR application. In this paper, a kHz‐level sub‐nanosecond electro‐optical Q‐switched Nd:YVO4 laser of SLM operation for remote sensing was demonstrated. By utilizing a compact resonator with a Volume Bragg Grating as output coupler, maximum SLM output power of 1.08 W and pulse width of 919 ps was obtained at 10 kHz. Moreover, we proposed a theoretical model to calculate the multimode threshold of the VBG‐coupled cavity. The longitudinal mode characteristics at four different cavity lengths were investigated experimentally and the results match well with the numerical simulations, which validates the theory. We expected the method could help to guide VBG‐coupled cavity design and construction. [ABSTRACT FROM AUTHOR]

Both pyrogallol-furfurylamine-based and pyrogallol-aniline-based di-benzoxazines (PG-FA and PG-A) possess a free hydroxyl and latent catalytic characteristics. To decrease the ring-opening polymerization (ROP) temperature of benzoxazine based on phenol and 4,4′-diaminodiphenylmethane (P-DDM) and increase simultaneously thermal property of its polymer, PG-FA and PG-A as catalysts were introduced into P-DDM. DSC and FTIR tests were used to investigate the effect of PG-FA and PG-A on the ROP of P-DDM; DMA, FTIR and TGA were performed to study their effects on the hydrogen bonds and thermal property of the cured P-DDM (PP-DDM). The results indicate that the ROP temperature of P-DDM remarkably decreased with the incorporation of PG-FA and PG-A. FTIR and DMA results illustrate that the total amounts of hydrogen bonds in PP-DDM increased with the addition of PG-FA or PG-A; however, its fraction of –OH⋯N (intra) and O−⋯+HN (intra) hydrogen bonds decreased. The decrease in –OH⋯N hydrogen bonds made the cross-linked density of polybenzoxazine increase, resulting in that the thermal stability of PP-DDM enhanced with the introduction of PG-FA and PG-A. [ABSTRACT FROM AUTHOR]

Past decades have seen a 'peak car' phenomenon which is indicated by a decline in vehicle kilometers traveled (VKT) in many countries. Although the determinants of VKT have been widely discussed, the theoretical arguments remain unresolved, particularly on the role of transport policies, socioeconomic factors and the built environment. This paper aims to contribute to new evidence for these arguments by examining an auto-dependent city, Wellington, New Zealand. A new bottom-up approach is applied to examine the VKT per capita in terms of its four decomposed main elements: trips (T), travel mode (V), travel distance (K), and car ownership (C) based on micro-level regressions. The results of the analysis show VKT per capita is significantly affected by parking supply, public transport quality and the built environment. These effects vary between trip type and population groups. Changing lifestyles are now major factors in the decrease of VKT. [ABSTRACT FROM AUTHOR]

• Land use has effect on residents' shopping in metro station areas nearest to home. • Modifiable Areal Unit Problem (MAUP) influences this effect. • Effect of service land use is different with general land use in attracting shopping. • Service land use accumulates greater effect with scales other than 800 m. • Potential social benefit of catchment area land use planning deserves more attention. Land use planning has been emphasised by both planners and researchers in providing incentives for local shopping. This study advances the body of knowledge by investigating land use and shopping trips in the catchment area for the metro station nearest to home, a unique context that serves both as a shopping destination and a transit origin for further shopping opportunities. Negative binomial and Tobit regressions were applied respectively to examine the effect of land use density on weekly shopping frequency in the station area nearest to home, and its share of individual's total shopping. The impact of the Modifiable Areal Unit Problem (MAUP) on these statistical relationships was addressed, with land use densities objectively measured in seven spatial scales using a radial buffer scheme. Results from all regressions suggest the existence of MAUP in influencing the sign, significance and size of the station area land use effects on shopping trips. A nuanced disaggregation of service types identifies both complementary and competitive relations among services, even under the same generic category, such as dining. The results show that model adopting 400 m radial buffer as measurement scale accumulates greater effect of service land use on station area shopping frequency, while model adopting the 1200 m scale accumulates greater effect of service land use on the station area shopping's share of individual's total shopping. This paper presents the sensitivity of effect of land use on shopping trips in station areas to the spatial scale of land use measurement. It provides pragmatic guidelines for station area planning to augment retail attractiveness and the social benefits of the catchment area for the metro station. [ABSTRACT FROM AUTHOR]

Transport equality is one of the key aspects of sustainable urban transport. Personal satisfaction with travel among different communities and social groups has become a main theme in the field of transport equality research. However, there has been little investigation of the expectation confirmation mechanism underneath this affective feeling. Moreover, there is not enough evidence on how the discrepancy between expected and actual travel relates to satisfaction. This study first identifies the regional and social disparity in general travel satisfaction among residents in Beijing, then discusses how the satisfaction response to the dissonance between expected and actual travel, and finally investigates the role of urban rail transport in this disparity. The results show that general travel satisfaction presents both regional and social disparities, with city-centre and middle-income residents having higher travel satisfaction. Disconfirmation of travel expectations partly explains travel dissatisfaction. The inconsistency between travel discrepancy level and satisfaction for lower income residents further reflects transport inequality issues, and it provides a clue for transport policymakers to promote transport equity from a sufficientarianism perspective. Public transport-related development has an important role in improving different aspects of travel satisfaction. Among them, higher level of mixed land use in metro station catchment areas and higher metro network centrality of the home nearest station help to increase the travel satisfaction of disadvantaged residents. This is realised via enhancing destination options for low-income or suburban residents, and via providing a relatively smooth and tidy travel experience for disadvantaged groups, who tend to use metro as a major travel mode. • Regional and social inequality in general travel satisfaction exist among residents in Beijing. • Disconfirmation of travel expectations partly explains travel dissatisfaction. • Public transport-related development has an important role in improving different aspects of travel satisfaction. • Mixed land use in metro station catchment areas increase the travel satisfaction of disadvantaged residents. • Living near to stations in the metro network help to increase the travel satisfaction of disadvantaged residents. [ABSTRACT FROM AUTHOR]

The construction of airport runways or other infrastructures on soft soil might risk damage and create potential hazards if inappropriate foundation treatments have been conducted. Preloading on soft soil is a commonly used ground improvement method in airport runway construction, owing to the cost efficiency and simplicity of this method. However, the theoretical basis for the design parameter estimation of this method has not been fully understood, for example, preloading height calculation and preloading time determination. In this paper, calculation models of settlement characteristics for soft soil preloading treatment and influence factors of preloading for soft soil are proposed, in accordance with Terzaghi one-dimensional consolidation theory. Preloading is counted as a dynamic process in this theory, and the settlement calculation model is expressed as an integration formula. In addition, a simplified calculation model is proposed in this paper for a specific condition of preloading treatment. Reliability of the models was verified with in situ data from an airport runway construction site in China. Results from multiple analysis reveal that preloading treatment can significantly increase the total settlement and consolidation, and accelerate the settlement rate of soft soil. Sensitivity analysis of the theoretical model found that preloading height is the key parameter affecting the preloading efficiency when ignoring the material type of soft soil. Moreover, the thickness of soft soil is the critical input parameter, as analyzing the factors affects the preloading height, and preloading treatment is a continues process rather than an instantaneous process, as can be noted from analyzing the settlement characteristics of the two loading conditions. The proposed settlement characteristic model provides valuable information for the design of preloading parameters of similar projects. Preloading is a simple and widely used method for improving the strength of soft soil; the design of preloading parameters mainly relies on the construction of a trial site or engineering judgment. The theoretical basis of this method is still weak. Thus, this paper proposes a settlement characteristic model under preloading conditions, which was verified by utilizing in situ data from an airport runway construction site. In addition, the influences of design parameters on such settlement characteristics as preloading height and thickness of backfill soil were analyzed. It was found that preloading height is the key parameter affecting the settlement characteristics of preloading treatment. In addition, sensitivity analysis was conducted on the preloading height design using an analytical model, and the results show that the thickness of soft soil is the critical factor affecting the preloading height. In that case, accurate site investigation is significant for the preloading design of soft soil. [ABSTRACT FROM AUTHOR]

In the present study, the oscillatory flow of Maxwell fluid in a long tube with a rectangular cross section is considered. The analytical expressions for velocity profile and phase difference are obtained, and particularly, the singularities of the exact solution are discussed. Furthermore, the convenient expressions of velocity and phase difference are given explicitly for calculations. The effects of the relaxation time and Deborah number on the velocity profile and phase difference are discussed numerically and graphically. [ABSTRACT FROM AUTHOR]

Medical knowledge extraction (MKE) plays a key role in natural language processing (NLP) research in electronic medical records (EMR), which are the important digital carriers for recording medical activities of patients. Named entity recognition (NER) and medical relation extraction (MRE) are two basic tasks of MKE. This study aims to improve the recognition accuracy of these two tasks by exploring deep learning methods. This study discussed and built two application scenes of bidirectional long short-term memory combined conditional random field (BiLSTM-CRF) model for NER and MRE tasks. In the data preprocessing of both tasks, a GloVe word embedding model was used to vectorize words. In the NER task, a sequence labeling strategy was used to classify each word tag by the joint probability distribution through the CRF layer. In the MRE task, the medical entity relation category was predicted by transforming the classification problem of a single entity into a sequence classification problem and linking the feature combinations between entities also through the CRF layer. Through the validation on the I2B2 2010 public dataset, the BiLSTM-CRF models built in this study got much better results than the baseline methods in the two tasks, where the F1-measure was up to 0.88 in NER task and 0.78 in MRE task. Moreover, the model converged faster and avoided problems such as overfitting. This study proved the good performance of deep learning on medical knowledge extraction. It also verified the feasibility of the BiLSTM-CRF model in different application scenarios, laying the foundation for the subsequent work in the EMR field. [ABSTRACT FROM AUTHOR]

Abstract Variation in atmospheric dust deposited on the Tibetan Plateau (TP) and its response to climate change are not well understood. In this study, a 65-year annually resolved (1950–2014) atmospheric dust proxy record is presented from the Mugagangqiong (MGGQ) ice core in the central Tibetan Plateau. There is a significant positive correlation between the dust concentration of the MGGQ ice core and dust days observed from meteorological stations in the Taklimakan Desert (r = 0.47, p < 0.001) and the central TP (r = 0.50, p < 0.001), indicating that the MGGQ dust record provides a good proxy for reconstructing an annual history of atmospheric dust-loading in this region. Two periods of enhanced dust deposition, (1962–1968 and 1975–1987), characterised by high concentrations and coarse grain size, suggest enhanced aridity, strong winds and active dust storm events. The lowest dust deposition period was identified as being between 1988 and 2000. Here we utilise 1975–1987 and 1988–2000 as typical high and low dust-loading periods, respectively, to discuss the possible dust mechanisms with the JRA-55 reanalysis data. During the high dust-loading period, dust concentration and flux were positively correlated with the mid-latitude zonal wind, suggesting that the high-level westerlies strengthened in northwestern China and transported more dust to the central TP than during the low dust-loading period. Dust concentration and flux decreased from the late 1980s and were positively correlated with weakened zonal winds and negatively correlated with precipitation in northwestern China from 1988 to 2000. Weakening westerlies and increasing precipitation at the dust source areas were responsible for this decrease in dust-loading during this period. Highlights • Sixty-five year atmospheric dust proxy record was established for a new Tibetan Plateau ice core site. • There are two distinct high concentration dusty periods (1962–1968 and 1975–1987). • The westerly wind strength is the main factor determining dust variation over the period 1975–1987. • Both westerly wind strength and precipitation control dust-loading over the 1988–2000 period. [ABSTRACT FROM AUTHOR]

This study addresses two issues from batch clustering using K‐means algorithm in colour image classification application. One of the major issues is the drifting phenomenon in the batch clustering due to the stochastic nature of the clustering procedure. Also in literature, the initial parameter is important to direct the clustering algorithm converge to the proper local solution. In this study, a new algorithm is proposed to address these two issues in application. Recently, a research found that the principal component analysis (PCA) result directly indicates the membership of the clusters in K‐means algorithm. Hence using this, the first part of the proposed algorithm shows the possibility to estimate the initial parameters accurately for K‐means with a hierarchical manner of PCA solution. In addition, a gradient descent approach is used for the global batch clustering to reduce the drifting and hence speed up convergence in the refining stage. All necessary proofs and justifications are also provided. The evaluation study has shown that the proposed algorithm performs better than the original K‐means clustering algorithms with various initial parameter estimation processes. [ABSTRACT FROM AUTHOR]

Highlights • Developed algorithm can be effectively used to detect different color clusters. • Digital image processing can be used to examine the soil layer mixing. • Developed method can be used to validate the numerical simulation results (i.e.DEM). Abstract Tillage operations are a vital part of agricultural crop production. Economic and environmental considerations are forcing farmers to manage soil tillage with optimum tool configurations to get the desirable soil condition. Soil disturbance caused by soil engaging tools, in particular soil layer mixing, is an important phenomenon that needs to be clearly understood. Current methods used to investigate soil layer mixing are limited, especially when multiple layer mixing needs to be investigated. The use of physical tracers is the most common approach. Although this method can provide some useful information, since it does not provide a full representation of how soil layers are moving or mixing, error-prone rough estimation is unavoidable. In this study, the mixing of soil layers was investigated using different coloured sands placed in layers at different depths (to continuously investigate the soil layer mixing). A new colour clustering algorithm to analyse such multi-coloured layer mixing performance was developed using K-means clustering with a PCA (principal component analysis) approach. The validation study of the proposed algorithm was conducted using the Columbia multispectral image database before implementation on the experimental coloured soil test. The test results showed that the proposed method and algorithm is effective in analysing multiple soil layer mixing. [ABSTRACT FROM AUTHOR]

Correlation of xeroderma pigmentosum complementation group F (XPF) expression with gastric cancer and prognosis was investigated. We randomly selected 76 gastric cancer patients who were admitted to the Second People's Hospital of Dezhou City and received treatment, and detected XPF expression in gastric cancer tissues (observation group) and normal gastric mucosa adjacent to tumor (control group) via immunohistochemistry. Correlation between XPF expression and clinicopathological indicators of gastric cancer was verified via single-factor Chi-square test. Cox's proportional hazard regression model was used in the analysis of influencing factors of patient's prognosis, and Kaplan-Meier was used to analyze the survival rates of XPF-positive and -negative patients. In the observation group, the XPF-positive rate was significantly higher than that in the control group with a statistically significant difference (P<0.05). Single-factor analysis showed that XPF expression was correlated with the family history and Laurén classification (P<0.05). Kaplan-Meier survival analysis revealed that the survival time of XPF-positive patients was shorter than that of XPF-negative patients (P<0.05). Multifactorial analysis using Cox's hazards model suggested that XPF was an independent factor affecting the prognosis of gastric cancer (P<0.05). In conclusion, XPF expression plays an important role in the occurrence and development of gastric cancer, and a high expression of XPF suggests a poor prognosis of gastric cancer patients. [ABSTRACT FROM AUTHOR]

Based on large statistical data and survey data, this article describes and analyzes the profound changes that have taken place in China's class structure since the beginning of the reform and opening-up. These changes include the unprecedented expansion of the workers and the emergence of migrant workers as a new social force; the large-scale decrease of the peasant population with growing differentiation and aging trends; the professional technicians becoming the main body of the middle class; the private entrepreneur stratum attracting wide attention; and new social strata and social groups continuously being formed, and so on. This article also discusses some of the controversial issues concerning the class structure in contemporary China, points out the opportunities and challenges that this dramatic social change brings, and provides some policy suggestions for correctly handling current class and stratum relations. [ABSTRACT FROM AUTHOR]

A geochemical method to characterize post-depositional melting and elution is demonstrated using inductively coupled plasma mass spectrometry to measure concentrations of dissolved and insoluble fractions of major crustal elements in snow samples collected from March 2006 to January 2010 at Urumqi Glacier No. 1, Tien Shan. Dust from these samples has compositional homogeneity, suggesting that dust has a stable dissolved fraction percentage (DFP, calculated as dissolved/(dissolved + insoluble)%). Calcium has the highest DFP (averaging 61.5 ± 19.4%), followed by Na (30.4 ± 19.6%), Mg (13.2 ± 9.8%), and K (7.9 ± 9.8%). Acid input can affect dissolution of Na and Ca. Taking DFP values of unmelted samples as the reference, the higher DFPs refer to strengthened dissolution from acid input, while the lower ones refer to elution. Based on the DFP difference between unmelted and eluted states, an elution sequence Ca > Na > Mg > K is obtained. Some details such as the beginning and the ending stages of elution can be found by DFP and acid input index, while using ion concentration is not capable of this. Our results reveal that acid input is an important mechanism for DFP changes, that the DFP index can provide an effective assessment of snow elution, and that this will aid in understanding low latitude ice cores. [ABSTRACT FROM AUTHOR]

Although the built environment–travel connection has been extensively examined in urban settings, evidence from rural and small towns is still scarce. This paper addresses this gap by exploring the influence of the built environment on travel mode choice using national-level survey data from 119 rural towns throughout China. The results show that rural built environment variables significantly influence mode choice, with socioeconomic, regional economic and natural environment factors controlled: at regional level, close proximity to county centres, highways and bus stops tend to reduce car dependence. At local level, small-scale, compact, and mixed land use encourage walking and bus use. The built environment influences mode choices for shopping trips more than commuting trips. The results suggest that spatial planning for land use and transport networks will be effective in shaping greener travel and sustainable transport development in rural areas of China and in developing countries with similar contexts. [ABSTRACT FROM AUTHOR]

With the rapid growth of power demand and the advancement of new power system intelligence, smart energy measurement system data quality and security are also facing the influence of diversified factors. To solve the series of problems such as low data prediction efficiency, poor security perception, and "data islands" of the new power system, this paper proposes a federated learning system based on the Improved Hunter–Prey Optimizer Optimized Wavelet Neural Network (IHPO-WNN) for the whole-domain power load prediction. An improved HPO algorithm based on Sine chaotic mapping, dynamic boundaries, and a parallel search mechanism is first proposed to improve the prediction and generalization ability of wavelet neural network models. Further considering the data privacy in each station area and the potential threat of cyber-attacks, a localized differential privacy-based federated learning architecture for load prediction is designed by using the above IHPO-WNN as a base model. In this paper, the actual dataset of a smart energy measurement master station is selected, and simulation experiments are carried out through MATLAB software to test and examine the performance of IHPO-WNN and the federal learning system, respectively, and the results show that the method proposed in this paper has high prediction accuracy and excellent practical performance. [ABSTRACT FROM AUTHOR]

Work on comparing cities in terms of their transport energy consumption and CO 2 emissions in the urban passenger transport sector has rarely been done using detailed travel activity data that takes into account city level differences in terms of economic development, population, and urban form. A personal activity based approach is necessary to better reflect travel behavior change results from different social, economic, urban form, technical, and transportation policy situations in the future. The present study extends the existing activity, modal share, energy intensity, fuel/carbon intensity (ASIF) modeling framework by disaggregating travel activity into key structural components and city-specific factors for 288 prefectural level cities in China. Testable econometric modeling systems were built to link mode split and mode specific travel distances with local economic and urban form characteristics in four different population sizes and two urban form types, based on 187 travel surveys in 108 Chinese cities in the past two decades. Scenarios of energy use and carbon emissions between 2010 (baseline) and 2050 were developed. Results showed that in 2010 urban passenger road transport in China generated 396 Mt CO 2 emissions and per capita urban passenger transport energy use increased as city size expanded. By 2030, under business as usual scenario assumptions, energy use in the urban passenger transport sector comprised 23.2 Mt of gasoline, 1.72 Mt of diesel, 3.36 billion M 3 of natural gas, and 0.62 billion kWh of electricity. While national policies targeting travel behavior change have been shown to mitigate emissions to some extent, urban transport policies targeted at specific spatial and temporal drivers of energy demand and emissions may be more effective in meeting policy goals. Short-term policies that promote car-pooling and ride sharing and medium-term policies that increase the cost of driving and promote public transport (such as transit oriented development, walkable neighborhood design, and parking pricing/restraint in city centers) help stabilize carbon emissions over the long term. However, the decision of building polycentric cities might have less significant impact on mitigating urban passenger transport in big cities. Moreover, large-scale promotion of electric vehicles should be designed from a long-term perspective rather than from a short-term one to achieve balanced carbon emissions in regard to the decarbonization process of electricity generation in China. [ABSTRACT FROM AUTHOR]

The fast economic growth of China along the last two decades has created a strong impact on the environment. The occurrence of heavy haze pollution days is the most visible effect. Although many researchers have studied such problem, a high number of spatio-temporal limitations in the recent studies were identified. From our best knowledge the long trends of PM 2.5 concentrations were not fully investigated in China, in particular the year-to-year trends and the seasonal and daily cycles. Therefore, in this work the PM 2.5 concentrations collected from automatic monitors from five urban sites located in megacities with different climatic zones in China were analysed: Beijing (40°N), Chengdu (31°N), Guangzhou (23°N), Shanghai (31°N) and Shenyang (43°N). For an inter-comparison a meta-analysis was carried out. An evaluation conducted since 1999 demonstrates that PM 2.5 concentrations have been reduced until 2008, period which match with the occurrence of the Olympic Games. However, a seasonal analysis highlight that such decrease occurs mostly during warmer seasons than cold seasons. During winter PM 2.5 concentrations are typically 1.3 to 2.7 higher than in summer. The average daily cycle shows that the lowest and highest PM 2.5 concentrations often occurs in the afternoon and evening hours respectively. Such daily variations are mostly driven by the daily variation of the boundary layer depth and emissions. Although the PM 2.5 levels have showing signs of improvement, even during the warming season the values are still too high in comparison with the annual environmental standards of China (35 μg m −3 ). Moreover, during cold seasons the north regions have values twice higher than this limit. Thus, to fulfil these standards the governmental mitigation measures need to be strongly reinforced in order to optimize the daily living energy consumption, primarily in the north regions of China and during the winter periods. [ABSTRACT FROM AUTHOR]

Detecting oxygen at the high concentration limit needs innovation. Room temperature ionic liquid trihexyl(tetradecyl)phosphonium trifluorotris(pentafluoroethyl) phosphate [P6,6,6,14][FAP] was tested as a solvent for oxygen detection through the electrochemical reduction of oxygen. Cyclic voltammetry of oxygen in nitrogen or carbon dioxide mixtures at different partial pressures was studied. The steady state current was shown to be linearly dependent on the oxygen partial pressure in high oxygen content (>77%) systems. Simultaneous detecting of oxygen and carbon dioxide is also realised in an oxygen/carbon dioxide mixture, providing proof-of-concept of high concentration oxygen and carbon dioxide dual sensing. [ABSTRACT FROM AUTHOR]

A liquid-convection-cooled Nd:YAG disk laser oscillator with an output power of 30.7 W and a slope efficiency of 14.1 % is built. By using large-eddy simulation model, the wavefront aberration induced by the turbulent flow is numerically calculated. In the experiment, a Shack-Hartmann wavefront sensor is used to measure the wavefront aberration and the laser intensity distribution. The RMS values and PV values of the beam wavefront and the phase stability of three feature points have been investigated. The experimental results prove that the turbulent flow with high flow velocity and high turbulent intensity can reduce the aberration of the flow field. [ABSTRACT FROM AUTHOR]

Preventing mucosal transmission of HIV is critical to halting the HIV epidemic. Novel approaches to preventing mucosal transmission are needed. Hyaluronic acid (HA) is a major extracellular component of mucosa and the primary ligand for the cell surface receptor CD44. CD44 enhances HIV infection of CD4+ T cells, but the role of HA in this process is not clear. To study this, virions were generated with CD44 (HIVCD44) or without CD44 (HIVmock). Exogenous HA reduced HIV infection of unstimulated CD4+ T cells in a CD44-dependent manner. Conversely, hyaluronidase-mediated reduction of endogenous HA on the cell surface enhanced HIV binding to and infection of unstimulated CD4+ T cells. Exogenous HA treatment reduced activation of protein kinase C alpha via CD44 on CD4+ T cells during infection with HIVCD44. These results reveal new roles for HA during the interaction of HIV with CD4+ T cells that may be relevant to mucosal HIV transmission and could be exploitable as a future strategy to prevent HIV infection. [ABSTRACT FROM AUTHOR]

A simple method is introduced which enables the simultaneous determination of both the maximum CO2 concentration and kinetics of CO2 uptake and release by a room temperature ionic liquid. This method is based upon the analysis of chronoamperometry recorded in bulk ionic liquid at intervals during exposure to CO2 and subsequent exposure to vacuum to remove the dissolved CO2. Comparing experimental data with a numerical model reveals the rate-limiting factors for both uptake and release of CO2. [ABSTRACT FROM AUTHOR]

Abstract: The high temperature thermal properties of materials are critical in industrial production and theoretic simulation. However, these properties are not always readily available. In this paper, a new technique was developed to obtain the temperature dependent thermal conductivity and specific heat through only one experiment. More importantly, this experiment was very convenient, since only thermal cycle recording was necessary. In addition, the finite element method and pattern search method were applied to optimize the supposed thermal property values. In order to avoid the convergence difficulty of the classical pattern search method, the step size adjusting function was rewritten. A solid sample and a particle like sample were selected to verify the measurement technique. The verification experiment showed that the thermal property results were accurate to some extent. [Copyright &y& Elsevier]

In submerged arc welding simulation, the heat source parameters are always decided by experience, and it usually leads to a high simulation error. This work is aimed to develop a methodology for the estimation of the heat source in submerged arc welding. A hybrid heat source model was applied on submerged arc welding simulation. The new heat source model was combined by a surface heat source model and the double ellipsoid heat source model. The surface heat source model was designed based on the Gaussian heat source model. The width and penetration of the weld pool were simulated and compared with the measurement results, and the width at 2 mm depth from the top surface was also considered to describe the shape of the weld pool more accurately. In order to reduce the simulation complexity, the sensitivity of heat source parameters was discussed. The heat source parameter corresponding to different experimental processes was obtained by modified pattern search method. The artificial neural network algorithm and the support vector machine algorithm were applied to predict the relationship between all possible process and the heat source parameters. The validation experiment showed that the prediction model was accurate. [ABSTRACT FROM AUTHOR]

Abstract: Although commercial tests are approved for detection of HIV-1 plasma viral loads ≥20 copies per milliliter (ml), only one specialized research assay has been reported to detect plasma viral loads as low as 1copy/ml. This manuscript describes a method of concentrating HIV-1 virions from up to 30ml of plasma, which can be combined with a commercial viral load test to create a widely available, reproducible assay for quantifying plasma HIV RNA levels less than 1copy/ml. Using this pre-analytically modified assay, samples with a known level of 0.5copy/ml were detected in 8 of 12 replicates (mean 0.47copy/ml; 95% confidence interval (CI) 0.14–0.81copy/ml) and samples with a known level of 1.0copy/ml were detected in 13 of 13 replicates (mean 1.96copy/ml; 95% CI 1.42–2.50copy/ml). By concentrating virus from 30ml of plasma, HIV RNA could be measured in 16 of 19 samples (84%) from 12 of 12 subjects (mean 2.77copy/ml; 95% CI 0.86–4.68copy/ml). The measured viral load correlated inversely (r =−0.78; p =0.028) with the total duration of viral suppression (viral load<40copies/ml). [Copyright &y& Elsevier]

Abstract: There remains a need for sensitive and cost-effective assays to monitor therapy in human immunodeficiency virus type-1 (HIV-1) infection. However, the genetic diversity of HIV poses difficulties for traditional real-time PCR assays that require long oligonucleotides probes. LNA™ probes may be useful in overcoming these limits to traditional probe design. A new application of LNA™ chemistry in a Taqman assay applicable to a wide range of HIV-1 subtypes is described. This assay, based on a 13-mer LNA™ probe that matches the majority of HIV-1 sequences in the Los Alamos database, exhibited a wide dynamic range (101–107 copies of HIV DNA), high sensitivity (limit of detection of 1 copy of HIV DNA in 105 cells), and broad applicability to a range of HIV-1 subtypes (including A, B, C, D, F, H, B/C, and A/E CRFs). Using the LNA™ probe assay, HIV-1 DNA was detected in all dried blood spots (DBS) from treatment naïve HIV-1 positive Ugandan children, and HIV DNA levels significantly correlated with viral RNA levels in plasma (r =0.765, p <0.0001). This approach to Taqman probe design should be explored further for use in diagnosis and monitoring of HIV in resource-limited settings, especially where several subtypes co-circulate. [Copyright &y& Elsevier]

China's reform practice over the past decade goes well beyond social transformation theories. While China's social transformation shares certain common features with that of other countries it has unique characteristics: the transformation of social structures was carried out with the transformation of the economic system, while the whole social transformation process showed a tendency to spread from rural to urban areas. The new experience of China's social transformation has attracted the attention of scholars from various disciplines across the world, especially sociologists and economists. Industrialization is a necessary condition for modernization. The transformation from a traditional to a modern society in essence is the transformation from an agricultural to an industrial one. After organizational changes in rural administration and occupational changes among the rural residents are taken into consideration, the actual number of urban residents still showed a substantial increase, the proportion of the total population accounting for about 30 per cent.

• Pervasive drought legacy effects on vegetation greenness were detected on the Tibetan Plateau. • Magnitude of the legacy effect is elevation dependent across the plateau. • This elevation dependence differs between alpine meadow and alpine steppe. • Distinct legacy effects may be due to diverse hydrothermal conditions across the altitude. Extreme drought events exert both immediate and prolonged influences on terrestrial ecosystems, yet the patterns and mechanisms of the delayed effects of extreme drought on alpine ecosystems remain largely unknown. In this study, we use satellite-derived normalized difference vegetation index (NDVI) data to examine the legacy effect of severe drought events on vegetation greenness across the Tibetan Plateau (TP). A pervasive, negative drought legacy effect, lasting about one year, is detected for all plant functional types including forests, shrubs and grasslands on the TP. The magnitude of the identified legacy effect, namely, the reduced growing-season NDVI in the first year post-drought, is spatially heterogeneous and exhibits a clear altitude dependence, while divergent relationships between elevation and the legacy effect are observed between alpine meadow and steppe. For alpine meadow, more pronounced legacy effects occur at higher altitudes with lower precipitation and temperature, suggesting a weaker drought resilience of alpine meadow under dryer and colder conditions. Whereas for alpine steppe, the magnitude of the negative legacies reduces as precipitation decreases along the elevation, which might be due to a greater adaptability to drought under more arid conditions that enables plant communities to recover to their normal state faster in these very dry regions. Our results advance the understanding of drought legacy effects on TP alpine ecosystems and highlight future avenues for research into how different alpine ecosystem types will respond to drought stress. [ABSTRACT FROM AUTHOR]

In this paper, a novel flexible piezoelectric thick-film generator is proposed to address the challenges caused by flexible deformation and high piezoelectricity. This improves the output charge of the generator, which breaks the limitation imposed by the rigid and brittle nature of traditional piezoelectric bulks on elastic strain and piezoelectric performance. Additionally, the low piezoelectric coefficient of piezoelectric polymer-based piezoelectric generators is also resolved. Given the high thickness precision of electrohydrodynamic jet printing technology, the facile production of 10-μm thick film components is achieved through a process of printing and layer-by-layer accumulation on a flexible substrate, which ensures the flexible deformation and piezoelectric characteristics of the functional film. To ensure that AC is converted into stable DC output, a bipolar charge collection circuit is developed. The printed thick film produces an excellent performance in surface uniformity and smoothness. Notably, the piezoelectric constant d 33 is measured to be approximately 80 pC/N, which is five times higher than the d 33 value of flexible PVDF films. Additionally, the strength of adhesion between the printed thick film and the flexible substrate is remarkably high, reaching up to 20 N, which is an order of magnitude higher than the magnetron sputtering method. In a single cycle, the forward charge output reaches an impressively high level of 260 nC, which is approximately thirteen times the charge transfer capability of PVDF flexible generator. Furthermore, a bipolar charge collection circuit is applied to convert AC into DC effectively. This increases the output voltage from 2 V to 4 V. The illumination of commercial electronic screens and 39 LED lights demonstrates the applicability of micron-scale jet-printed thick films in micro-energy harvesting. [ABSTRACT FROM AUTHOR]

The present study aims to clarify the role of ball pitch in Al 2 O 3 –SiC–C (ASC) refractory castables and investigate the influence of low temperature treatment on the composition, microstructural evolution, and properties of ASC refractory castables. By utilizing the expansion properties of ball pitch during heating, the castables undergo a low temperature treatment to induce the flow and expansion of ball pitch within the castables. This, in turn, fills the surrounding pores and enhances the physical properties of the castables. The results of this study demonstrate that low-temperature heat treatment of the castables at temperatures at 350 °C significantly improves the hot modulus of rupture, oxidation resistance, and slag resistance after sintering. This improvement is attributed to the optimized microstructure. In comparison to the corresponding samples without low temperature treatment, the high temperature modulus of rupture (HMOR) of the calcined castables treated at 350 °C increases by 33.3%. Additionally, the oxidation index and slag corrosion index after sintering at 1500 °C decrease by 39.6% and 87.31% respectively for the samples low temperature treated at 350 °C, as compared to the samples low temperature treated at 110 °C. This study provides a fresh perspective on the production of ASC castables with exceptional high temperature performance. [ABSTRACT FROM AUTHOR]

• Unlike the persistent greening trend in the northeastern part, the southwestern part was browning in 2000s but turned to greening in 2010s. • Precipitation was the key factor controlling NDVI dynamics in both northeastern and southwestern Tibetan Plateau. • Changes in the strength of Indian monsoon might contribute to the shift trend of NDVI in the southwestern part. Within the context of climate change (e.g., climate warming and changes in atmospheric circulation) the temporal dynamics of vegetation growth on the Tibetan Plateau (TP) have remained unclear, especially over the most recent decade. Using a normalized difference vegetation index (NDVI), we investigated vegetation dynamics on TP from 2000 to 2018, with a special focus on the northeastern part controlled by the westerlies and the southwestern part controlled by the Indian monsoon. Results indicate that the northeastern part had a consistent greening trend, but the southwestern part was browning in the 2000s and turned to greening in the 2010s. Precipitation was the key factor controlling NDVI dynamics in both parts. Differences in seasonality and trends in the strength of the atmospheric circulation might contributed to the distinct NDVI dynamics in these two parts. Our findings, in combination with previous reports on changes in the westerlies and Indian monsoon, highlight the importance of linking vegetation dynamics and atmospheric circulation for predicting the trend of plant growth on TP in the future. [ABSTRACT FROM AUTHOR]

• The measuring of angle of repose is generally based on subjective evaluation. • Digital image processing can be used to reduce the error of measuring angle of repose. • The developed algorithm can be used to accurately measure the angle of repose. Angle of repose (AOR) is one of the essential parameters to study the flowability of granular materials. It is also commonly used to calibrate the parameters of discrete element method (DEM). In practice, AOR is measured manually or using digital image processing (DIP). However, reliable and consistent measurement of AOR is still a challenging task due to the irregular or nonlinear shape of the material pile, particularly for the AOR of cohesive materials like soils. This study suggests an accurate and consistent way to measure AOR using DIP. The developed algorithm automatically finds the AOR of the material pile by a search algorithm for the unique maximal least square using linear regression analysis. The proposed algorithm is validated using customised templates with known angles, followed by an evaluation study against (a) an existing DIP method using a linear regression within "manually" selected region of interest and (b) the results of manual measurements using a protractor. The results showed that the developed algorithm can accurately measure and quantify AOR of soil piles. It was concluded from the results that the developed algorithm can be used to accurately measure AOR without error-prone subjective judgement. [ABSTRACT FROM AUTHOR]

• Spectral purity increases with the increase of injection intensity. • Spectral purity increases with the decrease of detuning frequency. • Frequency locking range increases for both high injection intensity and high gain. A comprehensive theoretical and experimental investigation of injection seeded Nd:YAG zigzag slab ring lasers is presented. The effects of injected intensity and detuning frequency on the dynamic process of mode competition are analyzed. A stable single frequency injection seeded Nd:YAG zigzag slab ring oscillator has been built by using the ramp-fire technique with a RbTiOPO 4 phase modulator. A linear ramp voltage is used and the detuning frequency is precisely controlled by firing the Q-switch with an adjustable delay time after the resonance condition. Both the simulation and the experiments carried out at various injection conditions have demonstrated that the spectral purity of the output pulse increases with the increase of injected intensity and with the decrease of detuning frequency, and that the frequency locking range increases for both high injected intensity and high gain. The experimental measurements of output pulse energy and pulse width are also in good agreement with the theoretical results. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) is playing an important role in radiation oncology. One of the most important applications is in radiotherapy physics. In this field, it has improved the automation of radiotherapy plan design and quality control (QC), thereby promoting and ensuring individualized precision treatment. This article reviews the applications and research on AI in the physics of radiotherapy and projects the prospects of AI in the following aspects: radiotherapy plan design, radiotherapy quality assurance, and QC, organs at risk contouring, dose prediction, etc. [ABSTRACT FROM AUTHOR]

SUMMARY: Rosa roxburghii and Rosa sterilis, two species belonging to the Rosaceae family, are widespread in the southwest of China. These species have gained recognition for their remarkable abundance of ascorbate in their fresh fruits, making them an ideal vitamin C resource. In this study, we generated two high‐quality chromosome‐scale genome assemblies for R. roxburghii and R. sterilis, with genome sizes of 504 and 981.2 Mb, respectively. Notably, we present a haplotype‐resolved, chromosome‐scale assembly for diploid R. sterilis. Our results indicated that R. sterilis originated from the hybridization of R. roxburghii and R. longicuspis. Genome analysis revealed the absence of recent whole‐genome duplications in both species and identified a series of duplicated genes that possibly contributing to the accumulation of flavonoids. We identified two genes in the ascorbate synthesis pathway, GGP and GalLDH, that show signs of positive selection, along with high expression levels of GDP‐d‐mannose 3′, 5′‐epimerase (GME) and GDP‐l‐galactose phosphorylase (GGP) during fruit development. Furthermore, through co‐expression network analysis, we identified key hub genes (MYB5 and bZIP) that likely regulate genes in the ascorbate synthesis pathway, promoting ascorbate biosynthesis. Additionally, we observed the expansion of terpene synthase genes in these two species and tissue expression patterns, suggesting their involvement in terpenoid biosynthesis. Our research provides valuable insights into genome evolution and the molecular basis of the high concentration of ascorbate in these two Rosa species. [ABSTRACT FROM AUTHOR]

Conventional strain sensors based on metals and semiconductors are rigid and cannot measure soft and stretchable objects. Thus, new strain sensors based on polymer/nanomaterial composites are attracting more interest. Although much effort has been dedicated to achieve high values of both sensitivity and stretchability with linearity, this work endeavors to search and establish guidelines for the development of stretchable strain sensors, by critically reviewing conventional sensors and examining recent progress. It starts from introducing key parameters for conventional strain sensors; these parameters are further discussed for their potential impact on new polymer/nanomaterial strain sensors. The work concludes that there are no general benchmarks for conventional strain sensors utilized in industry. From the findings, the authors suggest that stretchable strain sensors should be custom designed and developed to meet particular measurement requirements, in comparison with a generic aim of yielding a sensor with high degrees of stretchability, sensitivity, and linearity. Challenges are discussed, including reliability, calibration to be used as proper gauges, and soft data acquisition systems. [ABSTRACT FROM AUTHOR]

In this study, multilayer perceptron artificial neural networks are used to predict orthodontic treatment plans, including the determination of extraction-nonextraction, extraction patterns, and anchorage patterns. The neural network can output the feasibilities of several applicable treatment plans, offering orthodontists flexibility in making decisions. The neural network models show an accuracy of 94.0% for extraction-nonextraction prediction, with an area under the curve (AUC) of 0.982, a sensitivity of 94.6%, and a specificity of 93.8%. The accuracies of the extraction patterns and anchorage patterns are 84.2% and 92.8%, respectively. The most important features for prediction of the neural networks are "crowding, upper arch" "ANB" and "curve of Spee". For handling discrete input features with missing data, the average value method has a better complement performance than the k-nearest neighbors (k-NN) method; for handling continuous features with missing data, k-NN performs better than the other methods most of the time. These results indicate that the proposed method based on artificial neural networks can provide good guidance for orthodontic treatment planning for less-experienced orthodontists. [ABSTRACT FROM AUTHOR]

This study was undertaken to develop a new index, the Airport Runway Roughness Index (ARRI), that considers the effect of runway space when evaluating airport runway roughness. The difference between roadway and runway roughness evaluations is analysed in detail and the spatial effect is considered for a proposed runway roughness evaluation model. The evaluation of runway roughness should fully account for the dynamic responses of different typical aircraft during taxiing at the most unfavourable speed for the full cross-section of the runway. ARRI is defined according to the normalised weighted average of the vibration responses of typical aircraft models at the most unfavourable excitation waveband, the most unfavourable taxiing speed, and the most unfavourable lateral offset position within the longitudinal distance of the runway. Using runway three-dimensional full-section unevenness data collection equipment, a runway roughness evaluation procedure that is based on ARRI is proposed. The ARRI system provides qualitative improvement in terms of its representation ability, the rationality of the evaluation criteria, and the correlation of the indicators. [ABSTRACT FROM AUTHOR]

High energy, high repetition rates laser with excellent beam quality are fundamental components for LiDAR. In particular, high pulse energy is benefit for long distance range imaging. Narrow pulse width and high repetition rates are benefit for high resolution and high refresh rate operation of LiDAR. However, increasing the laser repetition rates will cause the pulse energy decreasing and the pulse width expanding. In order to achieve the requirements at the same time, we propose a 885 nm laser diode end‐pumped RTP Q‐switched Nd:YAG laser. Pulse pumping scheme was used to avoid heat accumulation. With a master oscillator power amplifier (MOPA) system, 40.5 mJ, 7.5 ns of 1064 nm pulses were obtained at 2 kHz. The beam quality factor M2 was measured as 1.60/1.51. Moreover, by frequency doubling with a LBO crystal, 16.4 mJ, 6.5 ns of 532 nm laser with the M2 factor of 1.52 and 1.50 was obtained. The 1064 and 532 nm pulses are suitable for avalanche photodiode arrays LiDAR and streak tube imaging LiDAR, respectively. The laser system is shown to accomplish high stability from temperature of −10°C to 30°C and vibration frequency of 10 to 100 Hz. [ABSTRACT FROM AUTHOR]

• This study mapped the primary climatic constraint on alpine plant photosynthesis. • Peak plant growth timing (DOY Pmax) was delayed 1.1 ± 0.1 days/100 m along elevation. • Elevational gradient in DOY Pmax decreased by −0.8 ± 0.2 days/100 m/decade since 2001. The Tibetan Plateau has experienced elevation-dependent climate warming, which has profoundly influenced the seasonal dynamics of plant growth. However, how peak photosynthesis timing (DOY Pmax), a key component of plant growth seasonality, responds to climate change on the Tibetan Plateau remains unclear. Here, we investigated the change in the elevational gradient in DOY Pmax on the Tibetan Plateau during 2001–2018 and its drivers. We mapped the primary climatic constraint on plant photosynthesis and found that it was temperature at 3000–4000 m a.s.l. in the central and eastern parts but soil water at 4000–5000 m a.s.l. in the southwestern part. DOY Pmax increased by 1.0 ± 0.1 days/100 m with increasing elevation from 3000 to 5000 m a.s.l., but the elevational gradient in DOY Pmax decreased by -0.8 ± 0.2 days/100 m/decade during 2001–2018 due to both direct and indirect effects of climate change. Specifically, at 3000–4000 m a.s.l., DOY Pmax was delayed because of the direct effect of the increase in soil water. At 4000–5000 m a.s.l., DOY Pmax advanced due to the warming-induced earlier green-up date in the central plateau and the drought-induced later spring phenology in the southwestern plateau. Such a change in plant growth seasonality should alter seasonal carbon cycle of alpine ecosystems, summer diets of the migrant herbivores and alpine plant–animal interactions along elevation gradients, but further efforts are needed to clarify how herbivores that migrate long distances, e.g., Tibetan antelope, adapt to changes in the elevational gradient in peak plant growth timing. [ABSTRACT FROM AUTHOR]

Aim: To establish and validate a prognostic nomogram of cholangiocarcinoma (CCA) using independent clinicopathological and genetic mutation factors. Methods: 213 patients with CCA (training cohort n = 151, validation cohort n = 62) diagnosed from 2012 to 2018 were included from multi-centers. Deep sequencing targeting 450 cancer genes was performed. Independent prognostic factors were selected by univariate and multivariate Cox analyses. The clinicopathological factors combined with (A)/without (B) the gene risk were used to establish nomograms for predicting overall survival (OS). The discriminative ability and calibration of the nomograms were assessed using C-index values, integrated discrimination improvement (IDI), decision curve analysis (DCA), and calibration plots. Results: The clinical baseline information and gene mutations in the training and validation cohorts were similar. SMAD4, BRCA2, KRAS, NF1, and TERT were found to be related with CCA prognosis. Patients were divided into low-, median-, and high-risk groups according to the gene mutation, the OS of which was 42.7 ± 2.7 ms (95% CI 37.5–48.0), 27.5 ± 2.1 ms (95% CI 23.3–31.7), and 19.8 ± 4.0 ms (95% CI 11.8–27.8) (p < 0.001), respectively. The systemic chemotherapy improved the OS in high and median risk groups, but not in the low-risk group. The C-indexes of the nomogram A and B were 0.779 (95% CI 0.693–0.865) and 0.725 (95% CI 0.619–0.831), p < 0.01, respectively. The IDI was 0.079. The DCA showed a good performance and the prognostic accuracy was validated in the external cohort. Conclusion: Gene risk has the potential to guide treatment decision for patients at different risks. The nomogram combined with gene risk showed a better accuracy in predicting OS of CCA than not. [ABSTRACT FROM AUTHOR]

It is widely believed air pollution is an obstacle to cycling as it has negative effects on cyclists’ health outcomes and deteriorates their cycling experiences. However, the empirical studies investigating the impact of air pollution on cycling behaviour remains scarce. The aim of this paper is to fill the gap by looking at Beijing as a case study. The authors conducted a survey of 307 cyclists on the days with different levels of air quality in terms of concentration of PM 2.5 in 2015. The results show that in the polluted weather, those who persist in cycling are more likely to be male, over 30 years old, lower income or those who travel short distances. Specifically, female cyclists have a higher tendency to shift from cycling to public transit than the males and medium and high-income earners are more likely to shift to using a car than low income earners. The residents’ subjective perceptions of safety and comfort have major effects on their cycling behaviour. A higher perception of comfort and safety is related to a higher possibility of continuing cycling when air quality became polluted. Cycling for commuting trips is less likely to be replaced by other modes than cycling for non-commuting trips, such as shopping. Results of this study reveal that improving air quality in a metropolitan area such as Beijing has co-benefits of cycling renaissance. The huge investments into cycling infrastructure should be integrated with policies designed to create an attractive environment for cycling. [ABSTRACT FROM AUTHOR]

In order to incorporate a range of surface applied materials into the soil profile to ameliorate crop production constraints, rotary spaders have recently been adopted in Australia. However, no fundamental studies have been carried out to quantify the mixing ability of rotary spaders. The discrete element method (DEM) has the potential to model soil to rotary spader interaction in terms of soil movement. In this study a full scale rotary spader was tested in the field and then simulated using DEM. The DEM model predicted top soil burial to a similar depth in the soil profile as was measured in the field. A method to compare and quantify soil movement was also developed using digital image processing. The forward soil movement which was not examined in the field was also simulated using DEM and it was found that higher forward speed increases the bite lengths, and hence results a heterogeneous top soil mixing. It was also found that in order to carry out a proper analysis, both cross section and forward soil movement must be considered while quantifying the mixing ability of the rotary spader. The results of this study proves that (1) DEM can be used to model soil to rotary spader interaction to analyse different operation conditions without time consuming and costly field tests which can only be performed certain times of the year and (2) digital image processing can be used as a method to quantify and validate simulations of field experiments. [ABSTRACT FROM AUTHOR]