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• Variables of ADS capability and guidance framework were designed based on TAM model. • Higher processing capability and graphic interface gained higher PB and trust. • The Higher the detecting capability, the slower the driver's take-over reaction. • PB mediated the effects of processing capability and guidance framework on trust. Individual trust can depend on the trade-off between perceived risk and perceived benefits (PBs). However, previous studies have primarily focused on risk-related factors, ignoring the potential trust factors of automated driving systems (ADS) in low-risk situations from the perspective of PBs. This study conceptualized the sub-dimensions of PB based on the Technology Acceptance Model (TAM), and examined the effects of two types of automation capability—processing capability and detecting capability—and interactive guidance framework on driving performance and driver trust in a simulated level 3 ADS. Results showed that processing capability and interactive guidance framework were critical factors in drivers' PB and trust in the ADS. Higher processing capability and the use of a graphic interface were associated with increased PB and trust. Detecting capability affected driving performance, earlier ADS detection corresponded with slower driver reaction times. PB mediated the effects of processing capability and interactive guidance framework on trust. These findings enhance the understanding of human trust in ADS from the PB perspective and provide guidance for designing guided tutorials and interactive guidance program to improve human trust and human-ADS interactions. [ABSTRACT FROM AUTHOR]

Bulk tin‐based monochalcogenides are composed of earth‐abundant, low‐cost, and non‐toxic chemical elements, which possess high thermoelectric properties making them candidate for waste heat recovery applications. Bandgap engineering offers opportunity to customize the characteristics of semiconductors as desired applications in microelectronic, thermoelectric, and so on. The bandgap of tin‐based monochalcogenides is systematically regulated by the solid‐solution method. The thermal and optical properties of SnSe(1–x)Sx (0 ≤ x ≤ 1) single crystals, synthesized successfully by a home‐modified Bridgman method, have been systematically investigated. A variety of characterizations, including x‐ray diffraction, electron microscopy, Raman spectroscopy, absorbance spectroscopy, and thermal analyzer, are employed to confirm the precise tuning of the component. As the S compositions increased from 0 to 1, the unit cell parameter, interplanar spacing, and optical phonon frequency exhibited a linear change, aligning with the expected bandgap shifts and calculated results. Our work will promote the advancement of the SnSe and SnS materials in areas including thermoelectricity and photovoltaics. [ABSTRACT FROM AUTHOR]

Much effort in the past few years has been made in tunnelling, however, no work has been reported so far on how to maintain the maximum tunnelling of complex optical fields in waveguides, due to the limitations of existing physical mechanisms. Here, a new paradigm is presented for realizing anomalous wave tunnelling through a general effective double‐barrier model constructed by dispersion engineering, while preserving mode information. The observed tunnelling mechanism is corroborated well by experimental results in the microwave realm. Specifically, evanescent waves bridge the gap between external space and potential well, allowing us to modulate the leaky modes within the potential well and thus achieve multiple resonant tunnelling. Due to the constant phase difference between adjacent maximum tunnelling, such mechanism broadens the potential of binary integrated devices. For example, assembling the tunnelling unit into arrays straightforwardly alleviates the trade‐off dilemma between diffraction law and cut‐off frequency. In addition, this approach provides an ideal toolbox for achieving multifunctional tunnelling across waveguide modes of various orders or polarizations, which can boost various applications in optical filters, tunneling lasers, optical switching, and sensing. [ABSTRACT FROM AUTHOR]

Intelligent compaction (IC) has emerged as a breakthrough technology that utilizes advanced sensing, data transmission, and control systems to optimize asphalt pavement compaction quality and efficiency. However, accurate assessment of compaction status remains challenging under real construction conditions. This paper reviewed recent progress and applications of smart sensors and machine learning (ML) to address existing limitations in IC. The principles and components of various advanced sensors deployed in IC systems were introduced, including SmartRock, fiber Bragg grating, and integrated circuit piezoelectric acceleration sensors. Case studies on utilizing these sensors for particle behavior monitoring, strain measurement, and impact data collection were reviewed. Meanwhile, common ML algorithms including regression, classification, clustering, and artificial neural networks were discussed. Practical examples of applying ML to estimate mechanical properties, evaluate overall compaction quality, and predict soil firmness through supervised and unsupervised models were examined. Results indicated smart sensors have enhanced compaction monitoring capabilities but require robustness improvements. ML provides a data-driven approach to complement traditional empirical methods but necessitates extensive field validation. Potential integration with digital construction technologies such as building information modeling and augmented reality was also explored. In conclusion, leveraging emerging sensing and artificial intelligence presents opportunities to optimize the IC process and address key challenges. However, cooperation across disciplines will be vital to test and refine technologies under real-world conditions. This study serves to advance understanding and highlight priority areas for future research toward the realization of IC's full potential. [ABSTRACT FROM AUTHOR]

A pellet-forming as-catalyst, CuO/Al2O3, was prepared by the precipitation–tablet molding method and characterized by the Brunner–Emmet–Teller (BET), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) techniques and TEM. The characterization results showed that the formed CuO/Al2O3 was in situ reduced to Cu/Al2O3 and Cu2O/ Al2O3 catalysts in the reaction system. The catalytic performance of catalyzing hydrogenation starch into glucose was investigated in an autoclave over CuO/Al2O3. The yield of glucose reached 83.16% at a temperature of 160 °C, a pressure of 1.8 MPa, a 100 g starch solution of 15 wt%, a catalyst dosage of 2.25%, a reaction time of 4 h, and a rotational speed of 630 r/min. The reusability of the catalyst was evaluated, and the glucose yield did not decrease obviously even after being reused for five consecutive cycles. Starch was converted into glucose through the synergistic action of Cu+ and Cu0 catalysis. This work is expected to provide valuable insights into the design of catalysts and the hydrogenation process for efficient starch hydrogenation. [ABSTRACT FROM AUTHOR]

The deformation behaviour of the asphalt concrete (AC) depends on the loading state and the temperature, accompanied by a large number of microcracks. In this study, the deformation and failure behaviour of the AC under uniaxial compression were investigated by the acoustic emission (AE). Both the stress–strain relationship and the energy dissipation were employed to analyse the macroscopic deformation of the specimen at low and medium temperatures. The AE parameters including count, energy and amplitude were measured in real-time during the loading process. The damage morphology of specimens was characterised by the failure location with the AE technology. Results show that with the rise of the temperature, the strength of AC specimens gradually decreased, which leads to a lower capacity in storing strain energy. The dissipative energy is greatly affected by the damage degree of the specimen. Both the event count and amplitude increased rapidly when the specimen failure occurred. The AE parameters are relatively sensitive to the deformation failure of asphalt mixtures influenced by the temperature. Furthermore, the results also imply that the AE method used in the present study to characterise the deformation failure in pavement engineering is more scientific and precise. [ABSTRACT FROM AUTHOR]

The Monte Carlo simulation (MCS) has been developed to estimate the strength distributions of heterogeneous materials influenced by different factors. The method presents a statistical correlation between the macroscopic properties and the non-uniform characteristics at meso scale. This study proposes an extensive MCS to investigate the influence of the aggregate morphology on deformation behaviour of unbound granular materials (UGMs) based on a real aggregate library and the discrete element method. Two indexes, elongation index (EI) and flatness index (FI), were used to evaluate the morphological characteristics of 3D aggregates rebuilt by the X-ray CT technique. Furthermore, repeated load triaxial tests of UGMs were simulated by 50 MCS samples. The effects of shapes and sizes of aggregates on deformation behaviours were statistically analysed. The results show that the deformation behaviour is dependent on the size and the EI distribution, but insensitive to the loading frequencies and FI distribution. [ABSTRACT FROM AUTHOR]

The Monte Carlo simulation (MCS) has been developed to estimate the strength distributions of heterogeneous materials influenced by different factors. The method presents a statistical correlation between the macroscopic properties and the non-uniform characteristics at meso scale. This study proposes an extensive MCS to investigate the influence of the aggregate morphology on deformation behaviour of unbound granular materials (UGMs) based on a real aggregate library and the discrete element method. Two indexes, elongation index (EI) and flatness index (FI), were used to evaluate the morphological characteristics of 3D aggregates rebuilt by the X-ray CT technique. Furthermore, repeated load triaxial tests of UGMs were simulated by 50 MCS samples. The effects of shapes and sizes of aggregates on deformation behaviours were statistically analysed. The results show that the deformation behaviour is dependent on the size and the EI distribution, but insensitive to the loading frequencies and FI distribution. [ABSTRACT FROM AUTHOR]

Background: To explore the effect and mechanism of action of miR-210 on postmenopausal osteoporosis (PMPO) in ovariectomized rats in vivo. Methods: An ovariectomized (OVX) rat model was established by ovariectomy. Tail vein injection was performed to overexpress and knock down miR-210 in OVX rats, followed by the collection of blood and femoral tissues from each group of rats. And quantitative real-time polymerase chain reaction (qRT-PCR) was applied to assess the expression level of miR-210 in femoral tissues of each group. Micro computed tomography (Micro CT) was adopted to scan the microstructure of the femoral trabecula in each group to obtain relevant data like bone mineral density (BMD), bone mineral content (BMC), trabecular bone volume fraction (BV/TV), trabecular thickness (Tb.Th), bone surface-to-volume ratio (BS/BV), and trabecular separation (Tb.Sp). ELISA was used for determining the level of bone alkaline phosphatase (BALP), amino-terminal propeptide of type I procollagen (PINP), osteocalcin (OCN), and C-terminal telopeptide of type I collagen (CTX-1) in serum; and Western blot for the protein level of Runt-related transcription factor 2 (Runx2), osteopontin (OPN), and collagen type I alpha 1 (COL1A1) in femoral tissues. Results: MiR-210 expression was significantly decreased in femoral tissues of OVX rats. Overexpression of miR-210 could obviously increase BMD, BMC, BV/TV and Tb.Th, whereas significantly decrease BS/BV and Tb.Sp in femurs of OVX rats. Moreover, miR-210 also downregulated BALP and CTX-1 level, upregulated PINP and OCN level in the serum of OVX rats promoted the expression of osteogenesis-related markers (Runx2, OPN and COL1A1) in the femur of OVX rats. Additionally, further pathway analysis revealed that high expression of miR-210 activated the vascular endothelial growth factor (VEGF)/Notch1 signaling pathway in the femur of OVX rats. Conclusion: High expression of miR-210 may improve the micromorphology of bone tissue and modulate bone formation and resorption in OVX rats by activating the VEGF/Notch1 signaling pathway, thereby alleviating osteoporosis. Consequently, miR-210 can serve as a biomarker for the diagnosis and treatment of osteoporosis in postmenopausal rats. [ABSTRACT FROM AUTHOR]

In the laboratory, there are significant differences in mechanical properties of asphalt mixtures with the same size gradation and asphalt binder, which is not conducive to evaluating and designing the pavement structure accurately. Meanwhile, the influence of aggregate segregation in height on the mechanical properties of asphalt mixtures is unclear. This study developed a new method to generate a three-dimensional (3D) model of the real composition and aggregate shape to characterize the aggregate segregation during Superpave gyratory compaction (SGC). The graphic segregation index (GPSI) is employed to assess the mixing degree of coarse aggregate and asphalt mortar within spatially variable specimens [i.e., Superpave-13, stone mastic asphalt (SMA-13), and open-graded asphalt friction course (OGFC-13) mixtures]. The results reveal that asphalt mixtures with different aggregate gradations have different compaction characteristics. For example, the increase of fine aggregates may reduce the strain energy and the average contact force during compaction. The compaction curves of the three gradation types were very different, which is attributed to different packing states and gyratory numbers. Aggregate segregation has a significant effect on micromechanical behavior. Specifically, the contact number and the proportion of strong contact force change considerably with height. In terms of segregation degree, the GPSI of OGFC-13 specimens was the highest, and the volume change of its fine particles created a leakage zone after the compaction. Additionally, this segregation had an increasing tendency with gyration numbers, and it was influenced by gradation types. Furthermore, the uniaxial compressive strength and cohesion of the Superpave-13 specimen decreased, whereas the friction angle increased with the increase of GPSI. [ABSTRACT FROM AUTHOR]

Background: Intermittent exotropia (IXT) is the most common type of strabismus, overminus lens (OML) therapy is frequently prescribed to treat IXT. Objectives: The purpose of this study was to compare the effectiveness of OML and observation in the treatment of IXT. Method: An exhaustive search of the literature in PubMed, Embase, Web of Science, and Cochrane Library databases was performed until July 2022. No language restrictions were used. The literature was rigorously screened according to eligibility criteria. Weighted mean differences and 95% confidence intervals (CIs) were calculated. Results: A total of 4 articles with 561 participants were included in this meta-analysis. Our pooled results showed that OML demonstrated superior outcomes compared with observation, with greater decreases in distance and near exodeviation control (MD = −1.08, 95% CI: −1.96 to −0.20, p = 0.02; MD, −0.64, 95% CI: −1.15 to −0.13, p < 0.001). Patients who received OML therapy had a greater decrease in the deviation at both distance and near (MD = −4.00, 95% CI: −7.03 to −0.98, p < 0.001; MD = −4.79, 95% CI: −6.29 to −3.30, p < 0.001). There was no statistical difference between the two groups in terms of post-treatment proximal stereopsis (MD, 0.00, 95% CI: −0.08 to 0.08, p = 1.00). Conclusions: The present meta-analysis indicated that OML therapy was effective in improving the control and decreasing exodeviation angle of IXT. However, it seemed not to be effective in improving the level of near stereopsis. [ABSTRACT FROM AUTHOR]

In recent years, novel magnifying lenses have generated much attention, not only because of their intriguing physics but also for their ability to achieve real‐time super‐resolution imaging. However, these super‐resolution magnifying lenses have been limited to virtual imaging and narrow band hindering the practical applications of magnifying lens. Here, a method is proposed to design a real‐imaging magnifying lens with ultrabroadband super‐resolution real‐time imaging capability based on conformal transformation optics. As a proof of concept, a two dimensional (2D) magnifying lens is designed, and its ability of ultrabroadband real imaging (working bandwidth of 104% of central frequency) with sub‐diffraction resolution in the microwave region is experimentally verified. It is found that the designed 2D magnifying lens has good robustness of fabrication errors, which provides more flexibility for practical applications. Furthermore, a three dimensional (3D) magnifying lens is designed by rotating the 2D magnifying lens along its symmetric axis. The 3D magnifying lens also maintains excellent imaging performance consistent with the one of 2D magnifying lens. Both 2D and 3D magnifying lenses can be integrated into conventional microscopes, expanding their capabilities for color super‐resolution magnified real imaging and opening a new realm in ultrabroadband super‐resolution real imaging. [ABSTRACT FROM AUTHOR]

Granular base material (GBM) is widely used as the base/subbase course of pavement structure. In the mechanic–empirical design of flexible pavement, both the resilient modulus and permanent deformation are the major deformation properties of base materials, related to early-stage distresses of the surface layer under traffic loading. However, since the microscopic interaction between aggregates of the GBM is quite complex, the deformation behavior was not to be understood merely empirically. This study aims to evaluate the macroscopic and microscopic behavior of the GBM under repeated load triaxial (RLT) testing by the discrete-element method. Both the size gradation and the aggregate shape were considered in numerical simulations. The modeling technology of a heterogeneous structure was developed and verified by laboratory results. The results showed that the resilient modulus measured by the developed simulation was in good agreement with that of laboratory tests, within errors of 5.0%. The deformation behavior of the GBM presents the stress-hardening characteristic that the resilient modulus of the GBM increases from 94.03 to 337.71 MPa with the growth of the volume stress and deviator stress. The microstructure of the GBM maintain a relatively stabilization in dynamic response and anisotropy changes during the cyclic loading and voids within aggregates play a role in buffering the change in internal stress. The principal contact normal trends to the direction of maximum bulk stress through small motions, and rotations of aggregates during the loading. It provides a robust mechanism for the resistance to deformation, which results in dispersing more stresses into the skeleton. [ABSTRACT FROM AUTHOR]

Recognizing excavator operators' sitting activities is crucial for improving their health, safety, and productivity. Moreover, it provides essential information for comprehending operators' behavior patterns and their interaction with construction equipment. However, limited research has been conducted on recognizing excavator operators' sitting activities. This paper presents a method for recognizing excavator operators' sitting activities by leveraging multi-sensor data and employing machine learning and deep learning algorithms. A multi-sensor system integrating interface pressure sensor arrays and inertial measurement units was developed to capture excavator operators' sitting activity information at a real construction site. Results suggest that the gated recurrent unit achieved outstanding performance, with 98.50% accuracy for static sitting postures and 94.25% accuracy for compound sitting actions. Moreover, several multi-sensor combination schemes were proposed to strike a balance between practicability and recognition accuracy. These findings demonstrate the feasibility and potential of the proposed approach for recognizing operators' sitting activities on construction sites. • There is a significant relationship between sitting activities and construction equipment operation performance. • A multi-sensor fusion-based approach was proposed for recognizing operators' sitting activities. • A multi-sensor system integrating two interface pressure sensor arrays and four IMUs was developed. • Operators' sitting activities were described in terms of static sitting postures and compound sitting actions. • Multiple multi-sensor combinations and classification algorithms were compared. [ABSTRACT FROM AUTHOR]

Recycling construction and demolition (C&D) wastes into useable aggregates in subgrade applications offers significant sustainability benefits. However, the characteristics of recycled aggregates, including particle morphology, crushing strength, and shear behavior, differ substantially from natural aggregates. This paper presented an extensive experimental study on the compaction and mechanics performances of recycled concrete and brick aggregates, with a particular focus on the effects of particle breakage and shape characteristics. The compaction of recycled aggregate specimens comprising three structural types was evaluated using heavy Marshall compaction (HMC) and Superpave gyratory compaction (SGC). The compaction characteristics and particle breakage were examined, enabling a profound understanding of the compaction mechanisms associated with both methods. Furthermore, triaxial shear tests were performed to scrutinize the influences of particle shape, compaction degree, and confining pressure on shear characteristics. Results showed that after 80 gyratory rotations in SGC, the compaction degree of recycled aggregates aligned with the targeted results obtained from HMC. Changes in fractal dimension after compaction exhibited direct correlations with the two-dimensional shape distribution. Axial coefficient, fractal dimension and confining pressure most strongly influenced shear strength. In light of these insights, prediction models for shear strength parameters were proposed using multiple regression analysis. Overall, the study provides valuable insights into the relationships between aggregate morphology, compaction response, breakage behavior, and shear performance. These findings can facilitate optimized design and construction using recycled aggregates to advance sustainable infrastructure development. • Image analysis quantitatively characterized morphology of recycled aggregates. • Significant crushing occurred during compaction, especially for coarser gradations. • Shear testing showed strain-hardening behavior followed expected trends. • Regression models successfully predicted shear strength from shape, density and pressure. [ABSTRACT FROM AUTHOR]

To reveal the fracture damage of asphalt mixture, an image-based numerical approach is proposed in this study considering the distribution of aggregate and asphalt mortar. Both digital image processing technique and discrete element method are applied to simulate the inhomogeneity of specimen and its fracture evolution at low temperature. At the same time, the acoustic emission (AE) activities are measured in laboratory to be compared with the micromechanical responses of numerical models. Results indicate that the developed method is suitable for modelling the numerical specimen of asphalt mixture, taking into account the size gradation and morphology of aggregates in the two-dimensional image. The numerical results of asphalt mixture have a good agreement with that of laboratory tests in cracking distribution and statistical probability. Cracks first appear on the aggregate–mortar interface, located in the upper and middle parts of the specimen, and then the brittle shear failure gradually propagates along the surface. Cumulative probabilities of both AE ringing counts and microfracture number follow the Weibull distribution. The numerical model has a significant advantage in the fracture evolution of asphalt mixture because the eccentric loading is unavoidable in laboratory tests due to personal and mechanical errors. [ABSTRACT FROM AUTHOR]

Background: Professional legislation and ethics guidelines for posthumous assisted reproduction (PAR) are lacking in China. This study aims to measure the attitudes of the general public, IVF couples, and assisted reproductive technology (ART) practitioners toward PAR in China. Methods: A multi-dimensional survey was designed, and electronic questionnaires were used. General demographic data, reproductive viewpoints, attitudes toward PAR, interactive ability to predict the partner's attitude toward PAR, and the legal attributes and rights to the disposal of posthumous embryos were evaluated. Results: The study found that the traditional Chinese viewpoints of fertility had changed. The approval rates for PAR were 79.10%, 55.32%, and 58.89%, in the general public, IVF couples, and ART practitioners, respectively. Most participants agreed that the psychological well-being of offspring should be previously considered before making a PAR decision (81.84%, 73.61%, and 76.98%, respectively). Multivariable logistic regression analysis showed that age, marital status, and gender were common influencing factors, while occupation, religion, and pregnancy history showed no influence on support for PAR. Males and females showed similar predictive abilities for their partners' attitudes toward PAR (57.87% for males, 61.12% for females). Intracouple agreement analysis showed that the consistent rate of consistency in attitudes toward PAR was 65.28%. Conclusion: The findings suggested that the approval rate of PAR was relatively high in China. Legislation and ethics guidelines for PAR may be considered in China. The psychological well-being of offspring should be considered before the implementation of PAR. Due to the very large regional and demographic differences in China, investigation of a larger samples of participants is necessary. Plain language summary: This study is based on the dilemma of how to deal with the remaining frozen embryos when a family structure changes (such as the accidental death of one or both partners). In this research, we systematically investigated the basic attitudes of different groups toward PAR, the consistency and prediction accuracy of attitudes between couples and their ability to predict their partners' attitudes, and the balance between offspring well-being and reproduction through a multi-dimensional cross-sectional survey in China. Our study illustrated that the approval rates of PAR were relatively high among the public, IVF couples and ART practitioners. Couples' attitude prediction accuracy and the intercouple concordance were moderate. The psychological well-being of offspring should be considered before the implementation of PAR. Moreover, an appropriate legal policy or specialized guidance for PAR may be considered and published in China. This research provides some advice and evidence for medical professionals and policymakers regarding practice and policymaking related to PAR. We also believe that this manuscript is valuable and helpful for all the researchers who are interested in the posthumous reproduction, not only in China. [ABSTRACT FROM AUTHOR]

Short-chain Perfluorinated compounds (PFCs), used as substitutes for highly toxic long-chain PFCs, are increasingly entering the aquatic environment. However, the toxicity of short-chain PFCs in the environment is still controversial. This study investigated the effects of short-chain perfluorobutanesulfonic acid (PFBS) at different concentrations (2.5, 6, 14.4, 36, and 90 mg/L) on M. aeruginosa growth under 12-day exposure and explored the molecular mechanism of toxicity using transcriptomics. The results showed that M. aeruginosa exhibited hormetic effects after exposure to PFBS. Low PFBS concentrations stimulated algal growth, whereas high PFBS concentrations inhibited it, and this inhibitory effect became progressively more pronounced with increasing PFBS exposure concentrations. Transcriptomics showed that PFBS promoted the pathways of photosynthesis, glycolysis, energy metabolism and peptidoglycan synthesis, providing the energy required for cell growth and maintaining cellular morphology. PFBS, on the other hand, caused growth inhibition in algae mainly through oxidative stress, streptomycin synthesis, and genetic damage. Our findings provide new insights into the toxicity and underlying mechanism of short-chain PFCs on algae and inform the understanding of the hormetic effect of short-chain PFCs, which are crucial for assessing their ecological risks in aquatic environments. [Display omitted] • M. aeruginosa exhibited hormetic effects after exposure to PFBS. • Photosynthesis is one of the targets of PFBS causing hormetic effect on M. aeruginosa. • PFBS exposure with high concentrations induced oxidative stress in M. aeruginosa. • PFBS with low concentrations promote cellular energy pathways in M. aeruginosa. [ABSTRACT FROM AUTHOR]

In view of the deficiency that traditional pavement performance evaluation index did not consider the influence of their difference on weight, the grade of the evaluation index also did not take into account intermediate state and the impact of uncertainty on the evaluation results, a determination method of pavement performance evaluation index weight based on entropy theory was developed. The unascertained measurement function of evaluation index was performed by left-half ladder distribution, and unascertained measurement matrix was obtained. The index weight was calculated by minimum entropy theory, and the practicability of this method was verified through a concrete example finally. The results show that there were different weights in different samples, which depended on index measurement function and were the overall characterization of comprehensive measurement of every index. The method which is based on the given weighting factor did not conform to the engineering facts. It was difficult to identify the importance of the pavement performance evaluation index in different samples. The balance of the various indexes is better to be considered in the proposed method, and the comprehensive situation of pavement performance is really reflected, which improves the evaluation of the reliability. [ABSTRACT FROM AUTHOR]

BMP and activin membrane-bound inhibitor (BAMBI) is a transmembrane glycoprotein, known as a pseudo-receptor for TGFβ, as, while its extracellular domain is similar to that of type I TGFβ receptors, its intracellular structure is shorter and lacks a serine/threonine phosphokinase signaling motif. BAMBI can regulate numerous biological phenomena, including glucose and lipid metabolism, inflammatory responses, and cell proliferation and differentiation. Furthermore, abnormal expression of BAMBI at the mRNA and protein levels contributes to various human pathologies, including obesity and cancer. In the present review, the structure of BAMBI is briefly introduced and its associated signaling pathways and physiological functions are described. Understanding of BAMBI structure and function may contribute to knowledge regarding the occurrence of diseases, including obesity and diabetes, among others. The present review provides a theoretical foundation for the development of BAMBI as a potential biomarker or therapeutic target. [ABSTRACT FROM AUTHOR]

Objective: To explore the predictive role of pretreatment albumin to globulin ratio (AGR) for prognosis in lung cancer. Methods: A comprehensive literature retrieval was performed in the PubMed, Cochrane Library, Web of Science and EMBASE databases up to May 20, 2019. The pooled hazard ratio (HR) and 95% confidence interval (CI) were applied to assess the correlation of pretreatment AGR with overall survival (OS) and disease-free survival (DFS). Sensitivity analysis was performed to assess the stability of results. Bess's funnel plot and Egger's test were conducted to detect potential publication bias. Results: Eight articles involving 3496 patients were included in our meta-analysis and all studies were from Asian countries. The results demonstrated that a low pretreatment AGR was significantly associated with poor OS (HR = 1.88, 95% CI: 1.49–2.38, P<0.001) and DFS (HR = 2.09, 95% CI: 1.56–2.81, P<0.001) and sensitivity analysis indicated the stability of above results. Publication bias test showed that there were two potentially unpublished articles, but they did not have a significant influence on the results of our meta-analysis. Conclusion: Our study manifested that pretreatment AGR was a reliable predictor for survival and it may contribute to the risk evaluation and therapy strategy formulation of lung cancer patients. [ABSTRACT FROM AUTHOR]

Visual simultaneous localization and mapping (VSLAM) enhances the navigation of autonomous agents in unfamiliar environments by progressively constructing maps and estimating poses. However, conventional VSLAM pipelines often exhibited degraded performance in dynamic environments featuring mobile objects. Recent research in deep learning led to notable progress in semantic segmentation, which involves assigning semantic labels to image pixels. The integration of semantic segmentation into VSLAM can effectively differentiate between static and dynamic elements in intricate scenes. This paper provided a comprehensive comparative review on leveraging semantic segmentation to improve major components of VSLAM, including visual odometry, loop closure detection, and environmental mapping. Key principles and methods for both traditional VSLAM and deep semantic segmentation were introduced. This paper presented an overview and comparative analysis of the technical implementations of semantic integration across various modules of the VSLAM pipeline. Furthermore, it examined the features and potential use cases associated with the fusion of VSLAM and semantics. It was found that the existing VSLAM model continued to face challenges related to computational complexity. Promising future research directions were identified, including efficient model design, multimodal fusion, online adaptation, dynamic scene reconstruction, and end-to-end joint optimization. This review shed light on the emerging paradigm of semantic VSLAM and how deep learning-enabled semantic reasoning could unlock new capabilities for autonomous intelligent systems to operate reliably in the real world. [ABSTRACT FROM AUTHOR]

• Emissions of volatile organic compounds (VOCs) in asphalt are investigated. • Factors influencing the emissions of VOCs in modified asphalt are analyzed. • A correlation between the release of VOCs and asphalt performance is built. With the booming construction of asphalt pavements, the volatile organic compounds (VOCs) emission becomes a growing threat to the environment and people's health. This paper aimed to investigate the impact of Buton rock asphalt (BRA) on VOCs emissions and the high-temperature rheological properties of modified asphalt. The investigation encompassed four different levels of BRA content, heating temperatures, and exposure durations, which were subjected to range analysis to ascertain the emission characteristics of BRA modified asphalt in terms of VOCs. Furthermore, the high-temperature rheological properties were assessed through dynamic shear rheometer (DSR) tests, and the correlation between asphalt VOCs characteristics and performance indicators was analyzed. The results showed that the emissions of VOCs increase significantly with rising temperatures and longer exposure to light. However, the incorporation of a 50% BRA modifier effectively reduced VOCs emissions by 8.84% while improving the high-temperature properties of asphalt. Additionally, a positive correlation was observed between the emission behavior of asphalt VOCs and the rheological properties of BRA modified asphalt. Overall, this study provides valuable insights into the environmental effect of BRA modified asphalt and it's potential as a sustainable alternative to traditional asphalt materials. [ABSTRACT FROM AUTHOR]

Cross-shelf transport is an important material exchange process between the shelf seas and open seas. The distribution characteristics of phytoplankton, surface sediment particle size, minerals, etc., all indicate the possible existence of a cross-shelf transport conduit from the inner shelf to the outer shelf off northern Taiwan. This study confirmed cross-shelf transport off northern Taiwan based on remote sensing sea surface temperature (SST) data and heat flux data, which can be divided into two patterns: cold eddy and cold water tongue. Furthermore, combined with AVISO sea surface level data, CCMP wind field data, the dynamic formation factors of different morphological characteristics of cross-shelf transport are studied. Topographic changes mainly induce cross-shelf transport off northern Taiwan and occur at the curve of isobath to deep water. When there is a strong thermal front along the coast, cross-shelf transport is more likely to occur. Against the steady, strong northerly wind, the Zhe-Min coastal current's southward flow and Kuroshio's invasion strengthened the temperature front and facilitated cross-shelf transport. Typhoon strengthened cross-shelf transport over northern Taiwan after passing through the southern part of the study area. This research has important implications to find the channel and transporting pattern for material exchange between the East China Sea and the West Pacific, which will contribute to the study of ecological environmental protection and seabed muddy area formation. • Confirmed the cross-shelf transport off northern Taiwan. • Dynamic formation factors of cross-shelf transport investigated. • Topographic changes mainly induce cross-shelf transport. • Typhoon Soulik strengthened cross-shelf transport. [ABSTRACT FROM AUTHOR]

In this study, a bacterial cellulose (BC) producing strain was isolated from Kombucha tea and identified as Komagataeibacter hansenii JR‐02 by morphological, physiological, and biochemical characterization and 16S rRNA sequence. Then, the media components and culture conditions for BC production were optimized. Result showed that the highest BC yield was 3.14 ± 0.22 and 8.36 ± 0.19 g/L after fermentation for 7 days under shaking and static cultivation, respectively. Moreover, it was interesting that JR‐02 could produce BC in nitrogen‐free medium with the highest yield of 0.76 ± 0.06 g/L/7days, and the possible nitrogen fixation gene nifH was cloned from its genomic DNA. The BC produced by JR‐02 was type‐I cellulose with high crystallinity and thermodynamic stability, which was revealed from Fourier transform infrared spectroscopy, X‐ray diffraction, and thermogravimetric analysis methods. The crystallinity of static and shaking cultured BC were 91.76% and 90.69%, respectively. The maximum rate of weight loss of static and shaking BC occurred at temperature of approximately 373.1 °C and 369.1 °C, respectively. Overall, these results indicated that K. hansenii JR‐02 had great potential to produce high crystallinity type‐I BC in manufacture. [ABSTRACT FROM AUTHOR]

• A novel fiber optic temperature sensor based on multimode interference is proposed. • The sensitivity is improved by splicing NCFs with different diameters and tapered fusion. • An ultra-high temperature sensitivity of −14.448 nm/K is achieved. • The reproductivity and repeatability of the proposed sensor are remarkable. For the advancement of temperature monitoring devices, research into high sensitivity fiber optic temperature sensors is valuable. This research suggests a fiber optic temperature sensor with great sensitivity. Specifically, the NCF (no core fiber) spliced with various diameters is employed within the multimode interference region of the typical SNS (single mode fiber-no core fiber-single mode fiber) sensor. The morphology of the splice sites connecting two NCFs is also regulated by fusing. The mixture of ethanol and glycerol is used to coat the entire structure. According to the experimental results, the proposed sensor can achieve a temperature sensitivity of −14.448 nm/°C. Additionally, the sensor has good performance in repeatability and temperature cycling thanks to its simple, dependable structure. It is anticipated that the relevant results will be useful for the development and applications of precise temperature measurement. [ABSTRACT FROM AUTHOR]

This document is an editorial titled "Characterization, Applications and New Technologies of Civil Engineering Materials and Structures." It discusses the importance of accurately evaluating and predicting the mechanical behavior of civil materials and structures in order to improve infrastructure durability and maintenance management. The document highlights a special issue that includes twenty research papers and one systematic review on various topics related to civil engineering materials, such as the use of solid wastes, material properties, and mechanical behavior. The aim of the special issue is to share innovative research and application methods in order to further develop civil engineering technology. The authors of the editorial express their gratitude to the authors, peer reviewers, and staff involved in the special issue. [Extracted from the article]

To reveal the meso-mechanical mechanism of shear behaviors in the graded crushed rocks (GCRs), which are heterogeneous in geometry and widely used in the flexible pavement, a numerical technique was proposed to simulate the geometric anisotropy of the GCRs using randomly generated models. Then, studies on meso-mechanical responses during the loading were performed through the biaxial shear test and California bearing ratio (CBR) test. The results showed that the changes of both friction and anisotropy had a similar trend with the particle size enlarging in the dense assembly, which maintain stable when the size is less than 3.0 mm. In addition, the breaking sieve (BS) between coarse and fine aggregates was six times of the base diameter (0.8 mm). The predicted shear properties in macrostructure were in good agreement with those laboratory measurements. For the shear behaviors, the fractures and force chains were mainly distributed in the area of action that was limited by force size and side boundary. [ABSTRACT FROM AUTHOR]

The electrical properties of pulsed laser deposited Sm[sub 2]O[sub 3] films have been studied. The dielectric constants are 9.6 and 12.8 for samples deposited at 400 and 683 °C, respectively. The presence of substantial densities of mobile positive charge and significant negative charge trapping has been evidenced. The leakage current densities are, typically, 10[sup -4] A cm[sup -2] for electric fields ∼0.24 MV cm[sup -1]. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

For improvement of finishing effect to the laser hardening mold's free-form surface with high hardness, double-layer elastic mechanics theory of pneumatic wheel based with softness consolidation abrasives (SCA) is analyzed. Under the annular stress around, ratio coefficient m of modulus of elasticity of abrasive layer to modulus of rubber layer and ratio coefficient n of thickness of abrasive layer to radius of stress have been bought in for establishing machining force model and deformation formula of double-layer elastic wheel. After that, a double-layer elastic model of the wheel has been established by ANSYS and the machining process has been simulated. Stress distribution and deformation rule are given by simulation. In the experiments, we use fiber to reinforce inner rubber layer and take binder to hold on abrasive particles. Microscopic analysis demonstrates that pneumatic wheel accords with the situation of double-layer elastic mechanic theory. Moreover, machining platform is established and empirical results show that pneumatic wheel can finish laser hardening mold's free-form surface efficiently. And conclusion shows pneumatic wheel with lower factor n can help to decrease R when it faces with concave surface and pneumatic wheel with higher factor n can improve machining efficiency to convex surface. [ABSTRACT FROM AUTHOR]

CF2H-substituted pyrazolines were synthesized by [3+2] cycloaddition between in situ generated CF2HCHN2 and electron-deficient alkenes. The representative CF2H-substituted pyrazoline was easily oxidized into the CF2H-substituted pyrazole, which are important in agrochemistry. [ABSTRACT FROM AUTHOR]

• A method for modeling and analyzing multiteam coordination task safety risks is proposed. • The multiteam coordination process is modeled by combining FRAM and multiteam system (MTS). • The multiplex network of inter-team functional interdependence is developed to investigate the MTS coordination structure. • The variability impact matrix is used to analyze MTS coordination process variability and corresponding safety risks. • The proposed method was applied to the shield tunneling construction scenarios. The dynamically changing working environment and complex task requirements in modern industries emphasize the necessity of multiteam with different functions to work collaboratively. The multiteam coordination performance dominates the task process and the achievement of the superordinate goal, which will inevitably influence task safety. Although previous research has broadly identified the importance of inter-team cooperation to task performance, the analysis of the relationship between multiteam coordination structure, process, and system safety has not been fully addressed. Moreover, there is still a lack of an effective method to quantitatively analyze the functional interdependencies, interaction processes, and potential safety risks among teams in multiteam coordination tasks. Based on the construction industry background, this study combines FRAM and multiplex network to describe the multiteam coordination structure and task process variability. The relationship between multiteam coordination performance and construction safety risk is qualitatively and quantitatively analyzed. Case studies are adopted to verify the feasibility of the proposed method. The findings demonstrate the method's advantages in revealing the details of the influence of multiteam coordination performance on complex task safety, which is beneficial for developing targeted countermeasures to control safety risks from the perspective of the multiteam system. [ABSTRACT FROM AUTHOR]

Background inward sodium current (I B,Na ) that influences cardiac pacemaking has been comparatively under-investigated. The aim of this study was to determine for the first time the properties and role of I B,Na in cells from the heart's secondary pacemaker, the atrioventricular node (AVN). Myocytes were isolated from the AVN of adult male rabbits and mice using mechanical and enzymatic dispersion. Background current was measured using whole-cell patch clamp and monovalent ion substitution with major voltage- and time-dependent conductances inhibited. In the absence of a selective pharmacological inhibitor of I B,Na , computer modelling was used to assess the physiological contribution of I B,Na . Net background current during voltage ramps was linear, reversing close to 0 mV. Switching between Tris- and Na + -containing extracellular solution in rabbit and mouse AVN cells revealed an inward I B,Na , with an increase in slope conductance in rabbit cells at − 50 mV from 0.54 ± 0.03 to 0.91 ± 0.05 nS (mean ± SEM; n = 61 cells). I B,Na magnitude varied in proportion to [Na + ] o . Other monovalent cations could substitute for Na + (Rb + > K + > Cs + > Na + > Li + ). The single-channel conductance with Na + as charge carrier estimated from noise-analysis was 3.2 ± 1.2 pS (n = 6). Ni 2 + (10 mM), Gd 3 + (100 μM), ruthenium red (100 μM), or amiloride (1 mM) produced modest reductions in I B,Na . Flufenamic acid was without significant effect, whilst La 3 + (100 μM) or extracellular acidosis (pH 6.3) inhibited the current by > 60%. Under the conditions of our AVN cell simulations, removal of I B,Na arrested spontaneous activity and, in a simulated 1D-strand, reduced conduction velocity by ~ 20%. I B,Na is carried by distinct low conductance monovalent non-selective cation channels and can influence AVN spontaneous activity and conduction. [ABSTRACT FROM AUTHOR]

Objective. We report on the distribution of traditional Chinese medicine (TCM) constitution in the first trimester and on the association between TCM constitution and maternal symptoms related to pregnancy. Methods. Participants were followed up until delivery to observe primary measures (gestational hypertension and gestational diabetes mellitus) and secondary measures (signs of miscarriage, miscarriage, nausea and vomiting, and sleepiness and defecation during pregnancy). Descriptive analysis, t-tests, chi-square tests, and logistic regression analysis were used in this study. Results. 61.8% of the participants had unbalanced constitutions. We did not find a significant association between the TCM constitution and gestational hypertension, gestational diabetes, miscarriage, signs of miscarriage, and defecation during pregnancy. And we found that women with unbalanced constitutions in early pregnancy had a greater likelihood of severe nausea and vomiting and poor sleep during pregnancy in the logistic regression analysis. Conclusions. These results have implications for female health care providers and policy makers. Identification of TCM constitution may be helpful for understanding nausea and vomiting and poor sleepiness during pregnancy, especially in the condition that can not be explained by modern medical science, and be helpful for making program to improve these uncomfortable symptoms. [ABSTRACT FROM AUTHOR]

We investigated the relationship between number of weekly working hours and the prevalence of diabetes in the urban Chinese population. Data regarding anthropometric measurements, fasting blood glucose level and number of hours worked per week were collected from 2228 workers in Shanghai, China (Mage = 44 years; 64% men). Participants were divided into three groups according to the number of hours worked per week (<45, 45–54 and ≥55), and multiple logistic regression analysis was conducted with diabetes as the dependent variable. Subjects with a HbA1c of 6.5% or above or those prescribed anti‐diabetic medications were defined as having diabetes. The multivariate adjusted odds ratio for having diabetes was found to be significantly higher for those who worked ≥55 h per week compared with those who worked <45 h per week, but only for men. This finding indicates that working long hours could be a risk factor for diabetes in Chinese male workers. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A facile strategy for the synthesis of isatins in high yield from N -alkyl-2-oxo-acetanilides has been developed via Friedel–Crafts alkylation using FeCl 3 as catalyst under air. This reaction proceeds through direct intramolecular addition and oxidation in one pot. Also this methodology is operationally simple, atom economical, and environment friendly. [ABSTRACT FROM AUTHOR]

In slope ecological restoration projects, reinforcing soil and promoting vegetation growth are essential measures. Guest soil spraying technology can be used to backfill modified soil and vegetation seeds onto the slope surface, resulting in successful ecological restoration. The use of organic polymer modifiers to reinforce soil has several benefits, such as high strength, effective results, and low pollution levels. Organic polymer soil modifiers can be divided into two categories: synthetic polymer modifiers and biopolymer modifiers. This paper provides a thorough review of the properties and interaction mechanisms of two types of polymer modifiers in soil consolidation. The properties of organic polymer modifiers make them applicable in soil and vegetation engineering on slopes. These modifiers can enhance soil mechanics, infiltration, and erosion resistance and promote vegetation growth. Therefore, the suitability of organic polymer modifiers for soil and vegetation engineering on slopes is demonstrated by their properties and potential for improvement in key areas. Furthermore, challenges and future prospects for slope protection technology using organic polymer modifiers are suggested. [ABSTRACT FROM AUTHOR]

A new method has been developed for the copper(I)-mediated trifluoromethylthiolation of α-bromoketone using commercial anhydrous potassium fluoride, elemental sulfur, and (trifluoromethyl)-trimethylsilane in anhydrous N , N -dimethylformamide. This protocol provides facile access to a variety of α-trifluoromethylthiolated carbonyl compounds in moderate to excellent yields under mild and ligand free conditions. [ABSTRACT FROM AUTHOR]

A short and efficient synthesis of (+)-subersic acid in 6 steps with an overall yield of 8.6% from (−)-Sclareol was presented using Mitsunobu reaction and Claisen rearrangement as critical steps. This elegant protocol gave a convenient access to gram scales of (+)-subersic acid, which could be a precursor for its structural analogues and for further bioactivity researches. [ABSTRACT FROM AUTHOR]

A new method has been developed for the copper-mediated trifluoromethylthiolation of allylic halides by using potassium fluoride, elemental sulfur, and (trifluoromethyl)trimethylsilane in anhydrous N, N-dimethylformamide. This protocol provides facile access to a variety of allylic trifluoromethyl thioethers in moderate to good yields under mild, ligand-free reaction conditions. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop a three-dimensional (3D) anatomically-detailed model of the rabbit right atrium containing the sinoatrial and atrioventricular nodes to study the electrophysiology of the nodes. A model was generated based on 3D images of a rabbit heart (atria and part of ventricles), obtained using high-resolution magnetic resonance imaging. Segmentation was carried out semi-manually. A 3D right atrium array model (∼3.16 million elements), including eighteen objects, was constructed. For description of cellular electrophysiology, the Rogers-modified FitzHugh-Nagumo model was further modified to allow control of the major characteristics of the action potential with relatively low computational resource requirements. Model parameters were chosen to simulate the action potentials in the sinoatrial node, atrial muscle, inferior nodal extension and penetrating bundle. The block zone was simulated as passive tissue. The sinoatrial node, crista terminalis, main branch and roof bundle were considered as anisotropic. We have simulated normal and abnormal electrophysiology of the two nodes. In accordance with experimental findings: (i) during sinus rhythm, conduction occurs down the interatrial septum and into the atrioventricular node via the fast pathway (conduction down the crista terminalis and into the atrioventricular node via the slow pathway is slower); (ii) during atrial fibrillation, the sinoatrial node is protected from overdrive by its long refractory period; and (iii) during atrial fibrillation, the atrioventricular node reduces the frequency of action potentials reaching the ventricles. The model is able to simulate ventricular echo beats. In summary, a 3D anatomical model of the right atrium containing the cardiac conduction system is able to simulate a wide range of classical nodal behaviours. [ABSTRACT FROM AUTHOR]

Highlights: [•] A MEMS microphone was studied via mixed flowing gas test and shock impact test. [•] Wire bond detaching was due to the nickel diffusion through the pad metallization. [•] Membrane embrittlement was due to the growth of surface silicon dioxide thin film. [•] Failures under shock impact were cracking of the diaphragm, backplate and runner. [Copyright &y& Elsevier]

Abstract: A versatile and highly efficient approach for the synthesis of nitroarenes from aromatic amine using m-CPBA has been developed. This oxidation reaction was operationally straightforward and proceeded to afford products in good isolated yields. [Copyright &y& Elsevier]

A dual slant-placed electrodes thin-film photocatalytic (PC) reactor was proposed and successfully applied to degrade Amaranth. In this PC reactor, both the TiO2/Ti photoanode and the Cu cathode are slant-placed in the reaction chamber, and aqueous thin-film formed on the surface of both electrodes as wastewater flowed over them. The degradation efficiency was significantly improved as a result of additional degradation at the cathode. When the TiO2photocatalyst was irradiated with UV light, photogenerated electrons were spontaneously transferred from the anode to the cathode, driven by the electric field self-generated between the TiO2/Ti anode and the Cu cathode, based on the principle of establishing a Schottky barrier. On the Cu cathode surface, the transferred photoelectrons either reacted with dissolved oxygen to form H2O2,which then oxidized the dye, resulting in indirect oxidation decolourization, or reacted with the dye, resulting in direct reduction decolourization. The colour removal efficiency of the cathode was about half that of the photoanode. These processes together with direct oxidation of the photogenerated holes on the photoanode gave dual electrode degradation of the dye, and the degradation efficiency was significantly improved. [ABSTRACT FROM AUTHOR]

The soil-rock mixture (SRM) is an excellent composite filler for subgrade, due to its renewable sources and high structural strength. It is still a challenge to evaluate the impact of gravel content (GC) and gravel shape on the shear behaviour of SRM in pavement engineering, due to the complex and uncontrollable microstructure of SRM. Thus, the aims of the study were: (i) to experimentally analyze the influence of GC and shape distribution of limestone and basalt gravels on shear strength of SRM at various stress conditions; and (ii) to numerically investigate the difference of mesoscale characteristics between SRM models considering irregular shape and proportion by discrete element method (DEM). The test results in the laboratory showed that the Gray correlation of gravel shape on shear strength was greater than that of GC. The numerical results showed that the developed DEM model could accurately predict the mechanical properties and deformation behavior of SRM. As GC increased, the contribution of contact force within gravel particles increased. Meanwhile, the interlocking work had a nonlinear positive correlation with the increase of sphericity. This study implied that morphological characteristics of gravel should be paid more attention to during the design of the SRM subgrade. [ABSTRACT FROM AUTHOR]

Neurogenic bladder (NGB) is an important complication of urinary tract dysfunction after spinal cord injury (SCI). However, using urodynamics and urography to guide therapy remains invasive and complicated. Therefore, the present study aimed to identify potential noninvasive biomarkers from urinary exosomes that can facilitate diagnosis and guide prognosis of patients with NGB subsequent to SCI. Urinary exosomes were isolated, and their proteome profile was analyzed by mass spectrometry. Transmission electron microscopy and Nanoparticle Tracking Analysis confirmed the size and morphological characteristics of urinary exosomes. In addition, bioinformatics analysis and parallel reaction monitoring (PRM) were used to screen candidate biomarkers. The selected biomarkers were validated using western blotting and ELISA. Mass spectrometry identified 134 upregulated proteins and 99 downregulated proteins between the vesicoureteral reflux (VUR) and non-VUR groups. A total of 18 candidate proteins were selected for PRM validation, but only vitronectin (VTN) and α-1 type I collagen (COL1A1) demonstrated significant differences. In the validation experiments using western blotting and ELISA, VTN was exclusively highly expressed in VUR patients compared with non-VUR patients. However, the ELISA results of COL1A1 revealed no significant difference when a larger sample size was used. Furthermore, a receiver operating characteristic curve of ELISA-based VTN demonstrated an area under the curve of 0.795 and 80% sensitivity at a threshold set to give 82.9% specificity. Collectively, these results suggested that VTN in urinary exosomes may be used as a biomarker to predict the progression and guide the prognosis of NGB. [ABSTRACT FROM AUTHOR]

Therelevance of the pathway through which the second proton isdelivered to the active site of P450cam and the subsequent coupling/uncouplingreactions has been investigated using Car–Parrinello moleculardynamics/molecular mechanics (CPMD/MM) dynamics simulations. Fivemodels have been prepared, representing delivery pathways in the wild-typeenzyme and its mutants in which Thr252 mutated into other residueswith different side-chain length and hydrophobicity. In the simulations,coupling reaction is observed in the wild-type enzyme (Model A) andits T252S mutant (Model B), while the uncoupling products are obtainedin the other three models (C, D, and E). Different from previous studies,a dynamic process of the last stage of coupling/uncoupling was observed.We found that the peroxide bond cleavage in coupling, the Fe–Obond stretching in uncoupling, proton transfer, and electron deliverytake place spontaneously. Moreover, besides the intrinsic chemicaldifferences between the two peroxide oxygen atoms, water moleculesin the active site and the proton transfer pathway may play an importantrole in the determination of coupling/uncoupling. We conclude thatby maintaining a specific proton transfer channel, Asp251–Thr252channel, the wild-type enzyme could efficiently deliver the secondproton to the ideal position for coupling reaction. [ABSTRACT FROM AUTHOR]