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Fatal traffic crashes involving commercial vehicles exhibit distinct characteristics and mechanisms compared to general traffic crashes, influenced by numerous factors that impact the resulting fatalities. This study presents a comprehensive analysis of significant commercial vehicle crashes in China over a nine-year period (2014-2022), exploring an extensive range of factors including driver behavior, road conditions, vehicle characteristics, and environmental aspects. Utilizing a hierarchical Bayesian ordered probit model that incorporates both categorical and random effects, the research offers nuanced insights into the probabilistic outcomes of fatal traffic crashes. The model's hierarchical structure enables the exploration of unobserved heterogeneities at individual and group levels. Key findings indicate that driver's behaviors like speeding and overloading significantly escalate the likelihood of fatal traffic crashes, particularly those resulting in 10 or more fatalities. The study also highlights the role of road class in fatal crashes, with primary and secondary roads being associated with higher risks of more severe fatal crashes. The analysis extends to the impact of vehicle type, noting a distinct increase in the probabilities of fatal crashes with passenger vehicles, while freight vehicles exhibit a more complex relationship with fatal crashes severity. The insights from this study underscore the urgent need for enhanced enforcement of speed limit and vehicle weight regulations, particularly through the deployment of advanced monitoring technologies on highways frequented by commercial vehicles, and targeted infrastructure improvements on primary and secondary roads. This approach offers a novel analytical framework for evaluating commercial traffic crashes, assisting policymakers in devising targeted safety interventions to reduce the incidence of commercial vehicle crashes., Author(s): Hongwen Xia [1,2,3]; Rengkui Liu (corresponding author) [1]; Pengfei Cui [1]; Wei Zhou [2,3]; Wenhui Luo [2,3] 1. Introduction Traffic crashes involving commercial vehicles have evolved into a pressing [...]

In the context of the advancing construction engineering field in China, there has been a significant increase in the adoption of building information modeling (BIM) technology within engineering–procurement–construction (EPC) projects. This emerging technology is expected to significantly influence the decision-making practices of professionals in the construction and engineering domain. Consequently, there is an urgent need for comprehensive research focused on construction management specifically pertaining to the effectiveness of construction developer management. This study examines seven representative EPC projects where BIM technology was implemented and it considers various factors that have the potential to influence project decision-making while taking into account time and cost considerations. A comprehensive multidimensional evaluation method that combines the analytic hierarchy process (AHP) and the fuzzy comprehensive evaluation method is introduced in this study. The results of this study emphasize that the efficiency enhancement strategies derived from the judgment indicator method demonstrate favorable practical outcomes. This research highlights the importance of a comprehensive evaluation method combining the AHP and the fuzzy comprehensive evaluation method to enhance decision-making efficiency for construction developer management staff.

With governments worldwide emphasizing environmental protection and the global focus on carbon reduction, the battery electric vehicle (BEV) industry has developed rapidly. An urban transportation network with BEVs as the main form of transportation will soon become mainstream. Motivated by the abovementioned background, a BEV transportation network design problem is investigated, and a network design model is established. The model aims to minimize the system travel time of BEV transportation networks and optimize the government's lane expansion scheme (the location and number of lanes) under a limited budget. To consider the travel characteristics of BEV drivers, the charging time, range anxiety, and bounded rationality factors are simultaneously incorporated into the model. A heuristic algorithm is designed based on the active set algorithm to obtain the local optimal solution to the actual-scale problem. Moreover, a cutting-plane method is used to convert the original problem into a different form, and a column generation technique is embedded in the abovementioned algorithm to avoid the enumeration of paths. Sensitivity analyses of different levels of rationality of BEV drivers and government investment scales are performed. The experimental results demonstrate that the model and algorithm can effectively solve the problem and provide decision support for the government in formulating transportation infrastructure construction policies., Author(s): Xu Xin [1]; Tao Zhang [1]; Cui Li [2]; Yanran Liu (corresponding author) [3]; Lingyu Gao [4]; Yuchuan Du [5] 1. Introduction As reported by the World Meteorological Organization [...]

Decision-making is an important component of autonomous driving perception, decision-making, planning, and control pipeline, which undertakes the task of how the ego vehicle makes high-level decision-making behaviors (such as lane change and car following) after sensing the environmental state, and then these high-level decision-making behaviors can be transmitted to the downstream planning and control module for specific low-level action execution. Based on the method of deep reinforcement learning (specifically, Deep Q network (DQN) and its variants), an integrated lateral and longitudinal decision-making model for autonomous driving is proposed in a multilane highway environment with both autonomous driving vehicle (ADV) and manual driving vehicle (MDV). The classic MOBIL and IDM models are used for the lateral and longitudinal decisions of MDV (i.e., lane changing and car following), while the lateral and longitudinal decisions of ADV are dominated by deep reinforcement learning models. In addition, this paper also uses the nonlinear kinematic bicycle model and two-point visual control model to realize the low-level control of both MDV and ADV. By setting a reasonable state, action, and reward function, this paper has carried out a large number of simulation experiments on the proposed autonomous driving decision-making model based on deep reinforcement learning in a three-lane road environment. The results show that under such scenario setting conditions, the deep reinforcement learning-based model proposed in this paper performs well in autonomous driving safety and travel efficiency. At the same time, when compared with the classical rule-based decision-making model (MOBIL&IDM), it is found that the model proposed in this paper can significantly achieve better results in episode rewards after stable training. In addition, through a large number of hyper-parameter tuning experiments, the performance of DQN, DDQN, and dueling DQN models, which are also deep reinforcement learning-based decision-making models, under different hyper-parametric configurations is compared and analyzed, which can provide a valuable reference for the specific scenario application of these models., Author(s): Jianxun Cui (corresponding author) [1]; Boyuan Zhao [1]; Mingcheng Qu [2] 1. Introduction Autonomous driving is hot research and practical issue in the fields of road traffic engineering, vehicle [...]

To investigate the route choice behavior of travelers under unexpected accidents, this study designs four different scenarios of travelers' route choice behavior experiments according to the severity of unexpected accidents. The bounded rationality characteristics of travelers, such as the time perception difference coefficient, psychological threshold effect coefficient, and scale effect, are introduced into the generalized random regret minimization (GRRM) model. An improved generalized random regret minimization (IGRRM) model is constructed based on travelers' route choice behavior under unexpected accidents. The collected data of travelers' route choice results under four different congestion-level scenarios are analyzed by the IGRRM model. The study finds that with the increase in congestion level, travelers are more willing to change the route; during the commute, travelers tend to choose the route with less travel time and angular cost; in the moderate and serious congestion scenarios, travelers no longer reject the detour route; attribute perception difference, scale effect, and psychological threshold effect; affect travelers' route choice behavior. The IGRRM model based on the route choice behavior of travelers can more accurately characterize the route choice behavior of travelers under unexpected accidents, provide a basis for traffic flow distribution under unexpected accidents, and benefit traffic management departments to take traffic control and guidance measures to ease the traffic congestion caused by unexpected accidents., Author(s): Minqing Zhu [1]; Peng Shi [2]; Hongjun Cui (corresponding author) [2]; Xinye Li [2]; Xinwei Ma [2] 1. Introduction Unexpected accidents are road traffic accidents that travelers suddenly encounter [...]

To improve the capacity of metro systems, it is important to evaluate and minimise headway, which is defined as the time interval calculated from “head to head” between two successive trains in this paper. With existing approaches for headway optimisation, the headway for moving block systems is often calculated based on the safe braking distance. However, the blocking time at movable elements (e.g., switches and crossings) and stops has special characteristics. Since train separation is dominated by a signalling system, the distance between two successive trains at movable elements and stops exceeds the safe braking distance. In this work, the theory for building a blocking time model and calculating line headway for moving block systems is investigated. A workflow to minimise line headway is designed to derive an optimised velocity profile before the identified bottlenecks. Several different optimisation algorithms, including grid search, Monte Carlo, and simulated annealing, are developed and compared. Among them, simulated annealing shows the best optimisation capability with the least computational effort. The designed algorithm has been tested for Hefei-Metro Line 1, and the line headway can be reduced from 116.776 seconds to 105.806 seconds. If the acceptable rate of the increased transport is set at 1%, the line capacity will increase by 6.5%., Author(s): Yong Cui (corresponding author) [1,2]; Qing Yu [3]; Chenyang Wang [4] 1. Introduction To improve the capacity of metro systems, it is important to evaluate and minimise headway, which [...]

During the development of oil reservoirs, a rapid increase in water cut following reservoir flooding leads to inefficient or ineffective circulation of injected water, rendering a significant portion of the remaining oil in the reservoir inaccessible. The displacement method using polymer particle dispersion systems effectively solves the issue of rapid water breakthrough in oil reservoirs. Owing to the particle phase separation phenomenon, polymer particles can selectively penetrate into the larger pores where water circulation is inefficient, enhance their flow resistance, and thereby achieve equilibrium displacement along with an increased swept volume. This paper investigates the heterogeneous distribution of polymer particles within a porous medium, incorporates the red blood cell dendrite concentration distribution theory from biological fluid mechanics, and develops a mathematical model to delineate the viscosity characteristics of polymer particle dispersion systems, taking into account the phase separation phenomenon. Building on this foundation, it formulates a capillary bundle model for the polymer particle dispersion system specifically designed for oil displacement and proceeds to determine its relative permeability curve. Simulation outcomes reveal that at a water saturation level of 0.063, the concentration of polymer particles in fractured large pore capillaries is markedly elevated, yet capillaries with a pore size under 26 µm remain devoid of polymer particles. With the increase of water saturation, the concentration of polymer particles in large pore capillaries reduces, whereas it progressively augments in medium pore capillaries. Upon reaching a peak water saturation of 0.751, capillaries smaller than 18 µm are entirely free of polymer particles. These findings suggest that the heterogeneous distribution of polymer particles markedly inhibits the percolation capabilities of the dispersed system following a water phase breakthrough, facilitating the entry of more dispersion into oil-laden capillaries and thus enhancing the flow capacity of the oil phase. [ABSTRACT FROM AUTHOR]

Yogurt consumption is a significant factor in reducing the risk of hypertension and preventing cardiovascular diseases. Although increasing evidence has emerged regarding the potential benefits of probiotics in hypertension, there is a lack of large, cross-sectional studies assessing the association between yogurt intake and blood pressure parameters. We aimed to evaluate the association between yogurt intake frequency and blood pressure. A cross-sectional study was designed using data from the National Health and Nutrition Examination Survey from 2003 to 2004 and 2005 to 2006. We included 3, 068 adults with blood pressure data and yogurt intake data. Multivariate regression analyses revealed significant inverse associations between yogurt and systolic blood pressure (P < 0.05), diastolic blood pressure (P < 0.05), and mean arterial pressure (P < 0.05) in nonhypertensive participants (n = 1 822) but not in hypertensive participants (n = 1 246). Furthermore, a high frequency of yogurt intake prevented hypertension; however, no additional antihypertensive effects were observed in patients already diagnosed with hypertension. [ABSTRACT FROM AUTHOR]

Poria sini decoction (PSD), a significant traditional Chinese herbal formula, is effective in liver cancer (LC) and chronic heart failure (CHF); however, little is known about its concurrent targeting mechanism. Methods. This study analyzed the potential molecular mechanism of PSD against the two distinct diseases using network pharmacology approaches, including multidatabase search, pharmacokinetic screening, network construction analysis, Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and molecular docking to elaborate the active components, signaling pathways, and potential mechanisms of PSD in the treatment of both LC and CHF. Results. A total of 155 active components and 193 potential targets in PSD were identified. Bioinformatics analysis revealed that quercetin, isorhamnetin, and naringenin, etc. may be potential candidate agents. TNF, AKT1, and IL6, etc. could become potential therapeutic targets. TNF-α, NF-κB, PI3K-AKT, and TRP signaling pathways might play an important role in PSD against LC and CHF. Molecular docking results showed that most screened active compounds could embed itself into target proteins with a high binding affinity, and the hydrogen bonds number ≥3 indicated a more stable conformation of the compounds and target proteins. Overall, quercetin and isorhamnetin were the main active components, and TNF and AKT1 were the primary targets for PSD treatment of LC and CHF. Conclusions. This study illustrated that quercetin contained in PSD played an important role in the treatment of LC and CHF by acting on the key gene of TP53 and downregulating the PI3K-AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Background/Aims. Circular RNAs (circRNAs) are often used for tumor diagnosis and treatment owing to their high stability, high expression abundance, and strong tissue specificity. The role of hsa_circ_0051908, a newly reported circRNA, in the development of hepatocellular carcinoma (HCC) is unknown. Materials and Methods. Hsa_circ_0051908 expression was determined using RT-qPCR. HCC cell proliferation, apoptosis, invasion, and migration were assessed using CCK-8 assay, EdU staining, TUNEL staining, flow cytometry, and transwell assay. The molecular mechanism was analyzed using western blotting. In addition, the role of hsa_circ_0051908 in tumor growth was evaluated in vivo. Results. Hsa_circ_0051908 expression was increased in both HCC tissues and cell lines. The proliferation, migration, and invasion of HCC cells were significantly decreased after hsa_circ_0051908 knockdown, while cell apoptosis was notably increased. Furthermore, we found that hsa_circ_0051908 silencing downregulated vimentin and Snail and upregulated E-cadherin. In vivo, hsa_circ_0051908 silencing significantly inhibited the growth of the tumor. Conclusions. Our data provide evidence that hsa_circ_0051908 promotes HCC progression partially by mediating the epithelial–mesenchymal transition process, and it may be used for HCC treatment. [ABSTRACT FROM AUTHOR]

Graphene quantum dots are quasi-zero-dimensional nanomaterials with unique physical and chemical properties. This study utilized a terahertz (THz) time-domain spectroscopy system to analyze the absorption characteristics of THz-waves by graphene quantum dots at different concentrations. Additionally, we applied electric fields and magnetic field to explore the THz-wave absorption properties of graphene quantum dots in greater detail. The results indicate that the THz absorbance of graphene quantum dots is positively correlated with sample concentration and applied electric field strength. However, it is negatively correlated with the intensity of the applied magnetic field. This work combines THz technology and microfluidic devices to propose a viable methodology for conducting in-depth study on graphene quantum dots. [ABSTRACT FROM AUTHOR]

Background. Genome data have been used to find novel allergen from house dust mites. Here, we aim to construct a chromosome-level genome assembly of Dermatophagoides farinae, a common allergenic mite species. Methods. We achieved a chromosome-level assembly of D. farinae's genome by integrating PacBio single-molecule real-time sequencing, Illumina paired-end sequencing, and Hi-C technology, followed by annotating allergens and mapping them to specific chromosomes. Results. A 62.43 Mb genome was assembled with a 0.52% heterozygosity rate and a 36.11 Merqury-estimated quality value. The assembled genome represents 92.1% completeness benchmarking universal single-copy orthologs with a scaffold N50 value of 7.11 Mb. Hi-C scaffolding of the genome resulted in construction of 10 pseudochromosomes. The genome comprises 13.01% (7.66 Mb) repetitive sequences and predicts 10,709 protein-coding genes, 96.57% of which are functionally annotated. Moreover, we identified and located 36 allergen groups on specific chromosomes, including allergens Der f 1, Der f 2, Der f 23, Der f 4, Der f 5, Der f 7, and Der f 21 located on chromosomes 2, 1, 7, 3, 4, 6, and 4, respectively. Conclusion. This comprehensive genomic data provides valuable insights into mite biology and evolutionary adaptations, potentially advancing D. farinae allergy research and treatment strategies. [ABSTRACT FROM AUTHOR]

Introduction. The development of combinatorial adjuvants is a promising strategy to boost vaccination efficiency. Accumulating evidence indicates that manganese exerts strong immunocompetence and will become an enormous potential adjuvant. Here, we described a novel combination of Mn2+ plus aluminum hydroxide (AH) adjuvant that significantly exhibited the synergistic immune effect. Methodology. Initially, IsdB3 proteins as the immune-dominant fragment of IsdB proteins derived from Staphylococcus aureus (S. aureus) were prepared. IsdB3 proteins were identified by western blotting. Furthermore, we immunized C57/B6 mice with IsdB3 proteins plus Mn2+ and AH adjuvant. After the second immunization, the proliferation of lymphocytes was measured by the cell counting kit-8 (CCK-8) and the level of IFN-γ, IL-4, IL-10, and IL-17 cytokine from spleen lymphocytes in mice and generation of the antibodies against IsdB3 in serum was detected with ELISA, and the protective immune response was assessed through S. aureus challenge. Results. IsdB3 proteins plus Mn2+ and AH obviously stimulated the proliferation of spleen lymphocytes and increased the secretion of IFN-γ, IL-4, IL-10, and IL-17 cytokine in mice, markedly enhanced the generation of the antibodies against IsdB3 in serum, observably decreased bacterial load in organs, and greatly improved the survival rate of mice. Conclusion. These data showed that the combination of Mn2+ and AH significantly acted a synergistic effect, reinforced the immunogenicity of IsdB3, and offered a new strategy to increase vaccine efficiency. [ABSTRACT FROM AUTHOR]

The burgeoning urbanization of major cities has precipitated a critical examination of deep foundation pit projects, with escalating costs, protracted construction phases, complex site conditions, and specialized technical requirements. Selecting the optimal design scheme from multiple alternatives in a multiattribute decision-making environment poses a significant challenge. This study presents a novel model tailored for the design of deep foundation pits in design-build (DB) contracting projects. The model combines multiattribute ideal point theory with the analytic hierarchy process to evaluate 22 key factors and their uncertainties. It computes the deviations of potential design schemes from ideal benchmarks across all considered attributes. By employing the lexicographic hierarchy aggregation operator, the model aggregates group-level deviations and linguistically weighted evaluations to calculate a comprehensive score for each design scheme. This approach aids in identifying the most suitable design to meet the deep foundation requirements of DB projects. The effectiveness of the model is demonstrated through its application in the decision-making process for a commercial hotel's deep foundation pit design scheme. The empirical findings affirm the model's ability to identify critical factors and accurately assess their impact on engineering design decisions in DB contracting projects. Among the four evaluated designs, the continuous retaining wall scheme achieved the lowest group deviation score, marking it as the preferred option. Consequently, this research offers a robust framework for making informed decisions in the design of deep foundation pits within DB contracting projects, effectively handling the complexities of uncertain linguistic evaluations and the collaboration of multiple attributes. [ABSTRACT FROM AUTHOR]

Background. The mainly lethal ability of ammunition fragments on creatures is achieved by hitting the effective organs or key parts of the biological body with high-speed projectiles. How to efficiently and accurately obtain the projectile speed and hitting position coordinates when the fragment hits the creature after the ammunition blast is the key to the scientific evaluation of ammunition power. Materials and Methods. For the measurement of fragment velocity and hitting coordinates, a series of flexible film circuit sensors can be generated by printing comb-like circuits on polyethylene terephthalate substrates using silver paste printing technology. These sensors are cheap, flexible, and easy to fold and can be printed into different shapes according to the characteristics of the test target to simulate the biological key organs or lethal parts. At the same time, the software and hardware design of the high-speed data signal reading and processing module can realize the data rapidly recording and processing and quickly give the ammunition fragment parameter test results. Results. The test accuracy of the fragment velocity of the laser light screen target and the flexible circuit sensor is compared through the live-fire test. It is proved that the test accuracy of the flexible sensor based on the polymer substrate can meet the accuracy requirements. The flexible sensor based on the organ simulation can quickly give the accurate hit position of the fragment. Conclusion. The newly polymer substrate printed circuit sensor system is a new type of sensor used to replace the laser screen target, and the copper comb printed circuit in the ammunition power test, which can improve the parameter test accuracy, reduce the test consumption, and improve the test quality. [ABSTRACT FROM AUTHOR]

Objective. The association between vitamin D status and inflammation remains unclear in hospitalized patients. Materials and Methods. We performed the current study based on real-world data from two teaching hospitals. Serum level of vitamin D (assessed by 25-hydroxyvitamin D) was evaluated within 2 days after admission. All the patients were further classified into three groups: deficiency (<12 ng/mL), insufficiency (12–20 ng/mL), and adequate (≥20 ng/mL). White blood cell (WBC) count, serum level of C-reactive protein (CRP), and procalcitonin were also measured and used to evaluate inflammation. Other potential covariates were abstracted from medical records. Charlson comorbidity index (CCI) was calculated to assess the severity of disease. Results. A total number of 35,528 hospitalized adult patients (21,171 men and 14,357 women) were included. The average age and BMI were 57.5 ± 16.2 years and 23.4 ± 3.7 kg/m2, respectively, while medium vitamin D level was 16.1 ng/mL (interquartile range: 11.4 ng/mL, 21.6 ng/mL) and median CCI was one point (interquartile range: 0 point, two points). The prevalence of deficiency and insufficiency was 28.0% and 40.5%. Multivariate linear regression model showed that serum level of vitamin D was significantly associated with WBC and CRP but not associated with procalcitonin. Each standard deviation (≈7.4 ng/mL) increase in vitamin D was associated with a decrease in WBC by 0.13 × 109/mL (95% CI: 0.2 × 109/mL, 0.06 × 109/mL) and 0.62 mg/L (95% CI: 0.88 mg/L, 0.37 mg/L) for CRP. Subgroup analysis and sensitivity analysis (excluding those whose eGFR <60 ml/min/1.73 m2, those whose daily calorie intake <1,000 kcal, and those who were recruited from Xin Hua hospital) generated similar results. Conclusions. The deficiency and insufficiency of vitamin D in the hospitalized adult patients was very common. However, the results should be interpreted with caution for limited representation of the whole inpatients. Low level of vitamin D was associated with inflammatory biomarkers, which provide the evidences to early intervention for lower the risk of infection. [ABSTRACT FROM AUTHOR]

Endothelial-to-mesenchymal transition (EndMT) is the process by which endothelial cells lose their endothelial properties and acquire mesenchymal characteristics. Dual-specific protein phosphatase 22 (DUSP22) inactivates various protein kinases and transcription factors by dephosphorylating serine/threonine residues: hence, it plays a key role in many diseases. The aim of this study was to explore the functional role of DUSP22 in EndMT. In the transforming growth factor-β-induced EndMT model in human umbilical vein endothelial cells (HUVECs), we observed a downregulation of DUSP22 expression. This DUSP22 deficiency could aggravate EndMT. Conversely, the overexpression of DUSP22 could ameliorate EndMT. We used signaling pathway inhibitors to verify our results and found that DUSP22 could regulate EndMT through the smad2/3 and the mitogen-activated protein kinase (MAPK) signaling pathways. In summary, DUSP22 ameliorates EndMT in HUVECs in vitro through the smad2/3 and MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

This work evaluated the effect of multiwalled carboxyl carbon nanotube (CNT-COOH), upon cement mortar. In order to obtain a homogeneous suspension, the CNT-COOH was dispersed in distilled water, and it then underwent an ultrasonication treatment. Samples of cement mortar were prepared with varying the additions of this suspension at 0.01%, 0.05%, and 0.10% by weight of the cement. These samples were tested in compression and for chloride migration in terms of diffusion coefficient. An increase in the CNT-COOH content led to an increase in the compressive strength. While there was an increase in the chloride diffusion coefficient up to 0.05% weight fraction, higher dosage led to a drop in the chloride diffusion coefficient with a further increase in the compressive strength. Using mercury intrusion porosimetry (MIP), it is shown that at a weight fraction of 0.10%, CNT-COOH effects a pore-size refinement by eliminating macropores (≥50 nm) and a 34% reduction in porosity. The (scanning electron microscopy) SEM and (X-ray diffraction) XRD analyses confirm that CNT-COOH leads to mature hydration products, nucleation effect, and a refined microstructure.

In this work, we analytically and numerically investigate the reflection characteristics of the airy beams impinging on graphene-substrate surfaces. The explicit analytical expressions for the electric and magnetic field components of the airy beams reflected from a graphene-substrate interface are derived. The local-field amplitude, Poynting vector, and spin and orbital angular momentum of the reflected airy beams with different graphene structure and beam parameters are presented and discussed. The results show that the reflection properties of the airy beams can be flexibly tuned by modulating the Fermi energy of the graphene and have a strong dependence on the incident angle and polarization state. These results may have potential applications in the modulation of airy beams and precise measurement of graphene structure parameters.

Under the repeated action of traffic and thermal loads, a cement concrete pavement slab may partially lose contact with its base course, and voids may develop underneath the slab. Such distress will greatly impact the pavement performance. To fill the voids and restore the base support to the slab, the technology of polymer grouting has been increasingly adopted in recent years due to its advantages of quick application and high efficiency. There is, however, a lack of research on the mechanistic responses and performance of such a repaired rigid pavement under coupled influences of thermal and traffic loads. Existing literature has mainly focused on normal cement concrete pavement structures (i.e., without polymer grouted voids). This study intends to fill the research gap by investigating the time-domain characteristics of thermal stress response of a cement concrete pavement with underlying voids filled with polymer grout, along with design traffic loads. The finite element method was adopted with a 3-dimensional nonlinear temperature field within the pavement. A program module was developed in the Abaqus FEA software environment for temperature effect analysis. It was found that under the coupling action of thermal and traffic loads, thermal stress had a greater influence on the critical slab stress at the slab corner than those at other slab locations. Through the comparative analysis before and after polymer grouting repair, the critical tensile stress at the slab corner under the vehicle and thermal loads can be effectively reduced. The polymer performance is stable after three years.

High-quality interface between propellant and insulation is the strict requirement difficult to quantify in solid rocket motor. In this study, the mixed mode delamination process of propellant and insulation interface is considered in double cantilever sandwich beam (DCSB) and single lap-joint (SLJ) test. The PPR cohesive zone model (CZM) and bilinear CZM in ABAQUS are introduced in this mixed fracture progress. In order to implement the PPR model in ABAQUS, user subroutine user element (UEL) is programmed for the novel CZM. Two simple pure mode I and mode II fracture problems are designed to check the accuracy of the UEL, and the result of verification is excellent. DCSB and SLJ test and their corresponding results are used again in the same inverse analysis with the two typical effective displacement-based and potential-based CZM. Base on the results, a series discussion and some conclusions are made. The debonding progress of the propellant and insulation interface in DCSB and SLJ test are mixed mode. The PPR CZM is prior in simulation than the bilinear CZM in ABAQUS because the PPR CZM is much more flexible with changeable traction-separation shape. The real normal and tangential displacement at damage initiation shows the unreasonable change in bilinear CZM in ABAQUS under mixed mode fracture. The PPR CZM and bilinear CZM in ABAQUS are all thickness-dependent model. The real initial stiffness and the critical displacement in the bilinear CZM and the real maximum traction in PPR model are dependent on the thickness of cohesive element. The different thickness dependence of the two model is caused by the implementation method.

Using some new techniques, the necessary and sufficient conditions for Kadec-Klee property of Orlicz function spaces equipped with s-norms are presented. An original method that was used in the process of inquiry and the obtained results also systematically complete and broaden the characterization of Kadec-Klee property of Orlicz spaces.

With the development of urban tunnels, more and more studies focus on the antiseismic design of tunnels. Setting up a shock absorption layer is a very effective means in the earthquake resistance of an urban tunnel. In this paper, in order to study the influence of the thickness of a shock absorption layer on the antiseismic effect of the urban shallow buried double arch rectangular tunnel, the Tengzhou–Fenghuang tunnel is used as the research background. Firstly, the model is established by finite element software to analyze the tunnel with 50 mm, 100 mm, and 150 mm thick shock absorption layers, and analyze the tunnel displacement, stress, and safety factors of different models under the action of a seismic wave. Finally, the calculation results are compared and analyzed with those of the model without the shock absorption layer to summarize the thickness of the shock absorption layer suitable for urban shallow buried rectangular tunnels. The results show that the displacement and stress of tunnel lining are significantly reduced, and the safety factor is significantly improved after setting the shock absorption layer. Among them, the tunnel with a 100 mm thick shock absorption layer has the greatest reduction in principal stresses, the greatest increase in safety factor, and the best antiseismic effect, while the construction costs are not high. It is recommended that the urban shallow buried double arch rectangular tunnel be constructed with a 100 mm thick shock absorption layer.

Objective. To investigate the clinical value of fractional exhaled nitric oxide (FeNO) in the diagnosis of pulmonary hypertension (PH) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods. In this study, the medical records of AECOPD patients were retrospectively reviewed. The patients were divided into AECOPD and AECOPD + PH groups based on the absence or presence of PH. Moreover, FeNO and other indexes were compared between the two groups. The value of FeNO in diagnosing AECOPD with PH was determined using the ROC curve. Results. A total of 83 patients were enrolled (56 in the AECOPD group and 27 in the AECOPD + PH group). The level of FeNO was significantly lower in the AECOPD + PH group than in the AECOPD group (P=0.022). Moreover, FeNO level (25.22 ± 8.45 ppb) was higher in the mild PH subgroup than in the moderate (16.64 ± 5.67 ppb, P=0.005) or severe (11.75 ± 2.36, P=0.002) PH subgroups. FeNO level was positively correlated with C-reactive protein in AECOPD patients while negatively correlated with brain natriuretic peptide in the AECOPD + PH group. ROC analysis showed that the optimal cutoff value of FeNO in the diagnosis of AECOPD with PH was 24.5 ppb. Conclusion. FeNO level at admission can act as an indicator for PH diagnosis in AECOPD patients.