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Traditional asphalt mix design methods primarily rely on experience, consuming immense time and resources. Currently, advanced machine learning (ML) method can accelerate the asphalt mix design procedure. However, historical data on asphalt mix design exhibit high variability, and the outputs of ML models are often challenging to interpret. To address these issues, this study selectively utilized outlier detection algorithms for data preprocessing and employed interpretable ML to predict and explain the volumetric properties of the mixtures, achieving an automated and rapid mix design method. A database (1525 sets of data) of volumetric properties was established based on experimental data of the engineering site. Z -score, KDE (kernel density estimation) and LOF (local outlier factor) methods were employed to detect outliers of the database. Three ML models were trained to predict the volumetric properties of mixture (air void and voids in mineral aggregate), based on material proportion, gradation morphological and material performance features. The SHAP method was used to interpret the extreme gradient boosting (XGB) model, quantifying feature importance, and aiding in decision-making. Finally, an asphalt mix design framework was proposed. The results indicate that the combination of KDE and LOF methods for outlier detection enabled the machine learning model to achieve optimal performance. The XGB model had the best prediction effect on volumetric properties. According to the SHAP method results, the influence of the critical features on the results was explained by the physical laws. The method proposed effectively reducing the design time and costs. The feasibility of the proposed design method was proved by the case study. [Display omitted] • Combining kernel density estimation and local outlier factor for outlier detection. • SHAP method was used to explain the XGB model. • The influence of critical features on the volumetric properties was determined. • The proposed asphalt mix design method can reduce the design procedure by 70%. [ABSTRACT FROM AUTHOR]

Photoelectric synergistic degradation of dye wastewater has been developed. In this experiment, we prepared Nitrogen-doped titanium dioxide-graphene/nickel foam (N/TiO 2 -Gr/F–Ni) by electrophoresis and impregnation methods, to degrade methyl orange (MO) aqueous solution. Firstly, nitrogen-doped titanium dioxide particle (N/TiO 2) was prepared by the sol-gel method, which showed a photocatalytic degradation catalytic kinetic constant of 1.8 × 10−2 min−1 under simulated sunlight. Meanwhile, graphene (Gr) was loaded on nickel foam (F–Ni) to prepare Gr/F–Ni electrode by electrophoresis method, which obtained a catalytic kinetic constant of 1.15 × 10−2 min−1 at 10 V. Finally, N/TiO 2 was loaded on Gr/F–Ni to prepare N/TiO 2 -Gr/F–Ni photoelectrode by electrophoresis and impregnation methods, which had a catalytic kinetic constant of 3.96 × 10−2 min−1 at 10 V and under 1 sun. The results show that there is a synergistic effect between light degradation and electro-Fenton oxidation because the bonding electrons in N/TiO 2 are activated to produce photogenerated electron-hole pairs. On the other hand, the separation efficiency of the photogenerated electron is enhanced by the Gr. [ABSTRACT FROM AUTHOR]

Heterogeneous void distribution is a common phenomenon in asphalt mixtures and is closely linked to their performance. Therefore, it is necessary to propose a physically meaningful and accurately fitting vertical void distribution model for asphalt mixtures, so as to realize the quantitative evaluation of void distribution. In this study, virtual and actual specimens of asphalt mixture were established using discrete element method (DEM), laboratory compaction, and field coring methods. The vertical void distribution of different specimens was obtained through CT scanning and image processing technology. The impact of various factors, including gradation type, nominal maximum aggregate size, and specimen height on void distribution, was investigated. Subsequently, a three-stage exponential model was proposed to characterize the vertical void distribution in asphalt mixture. The physical significance of different fitting parameters in the model was elucidated. The results indicate that the vertical void distribution of DEM models and laboratory compaction specimens exhibited a bathtub shape, while the vertical void distribution of pavement core specimens exhibited a semi-bathtub shape. The void distribution of the mixture was affected by gradation type, nominal maximum aggregate size and specimen height. The vertical void distribution of asphalt mixture could be effectively characterized by the three-stage exponential model. In addition, the root mean squared error of the second stage data from the three-stage exponential model was also proposed to evaluate the void distribution uniformity. • A three-stage exponential model was proposed to characterize the vertical void distribution. • The feasibility of the three-stage model was analyzed through simulation and test results. • An evaluation method for the uniformity of vertical void distribution was proposed. • The potential application of the three-stage exponential model was discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] Based on grouting asphalt concrete, titanium dioxide (TiO 2) and magnesium phosphate cement materials were selected as reflective grouting materials (RGM) to prepare reflective grouting asphalt concrete (RGAC), which was used to improve the reflective capacity, mechanical strength and cooling effect of pavement. The reflectance and mechanical properties of RGM were characterized through color characteristic, mechanical strength, reflectance and bonding strength tests. The results show that the spectral reflectance of RGM was 4.61 times higher than that of asphalt, but the addition of TiO 2 reduced its mechanical and bonding strength. The visual and cooling effects of RGAC were analyzed by digital image processing technology and indoor irradiation test. The addition of TiO 2 improved the visual uniformity and lightness of the surface, which had a good reflection effect. Compared with conventional asphalt mixture, the maximum surface temperature of RGAC reduced by 20.2 ℃. RGAC is a potential material of thermal reflective asphalt pavement construction. [ABSTRACT FROM AUTHOR]

Tryptophan (TRP) metabolism plays a crucial role in pathology and physiology. An imbalance in TRP metabolism has been implicated in the pathology of renal failure. To explore the changes in the TRP profile that occurred in renal failure, we induced experimental models of renal ischemia-reperfusion injury (RIRI) and chronic renal failure (CRF) in rats. A simple, rapid and sensitive method coupling ultra-high-performance liquid chromatography to triple quadrupole mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of TRP and its seven major metabolites in plasma. The method was validated base on linearity, accuracy, precision, stability, recovery and the matrix effect. In the RIRI group, the levels of kynurenine (KYN), 5-hydroxyindoleacetic acid (5-HIAA), tryptamine (Trpm) and kynurenic acid (KA) were increased, and the level of TRP was decreased significantly compared with those of sham group. Moreover, the levels of most of the metabolites measured using the proposed method changed significantly with CRF progression. In the CRF group, the levels of KYN, 5-HIAA, Trpm, KA, 3-hydroxyanthranilic acid (3-HAA) and 3-hydroxykynurenine (3-HK) were dramatically elevated, and the level of TRP was markedly reduced compared with those of the CON group. Plasma precursor metabolite/product metabolite ratios were calculated to characterize enzyme activity. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) of the metabolites were performed for both groups. A Spearman correlation coefficient analysis between the metabolite concentrations and renal injury indicators was performed. We identified KYN, TRP, and 5-HIAA as potential metabolite biomarkers for AKI, and 5-HIAA, TRP, 3-HAA, KA, KYN and 3-HK as potential metabolite biomarkers for CRF (VIP>1 and p < 0.05). These results showed significant changes in the tryptophan metabolism profile under the two types of renal failure. In summary, the results of our study depict the changes in the TRP pathway, reveal the role of the TRP pathway in AKI and CRF, and provide insight into finding potential peripheral biomarkers of renal failure and elucidating the mechanism of diseases related to TRP metabolism disorders. [Display omitted] • TRP and its 7 metabolites were simultaneously determined by UPLC-MS/MS in 4.5 min. • Application of the method to samples from acute and chronic renal failure rats. • Correlation between TRP metabolism and renal failure was investigated. • TRP, KYN and 5-HIAA were identified as potential biomarkers for AKI. • TRP and its five metabolites were identified as potential biomarkers for CRF. [ABSTRACT FROM AUTHOR]

• Glass microsphere was used to prepare low-thermal-conductivity asphalt mixture. • The thermal conductivity of asphalt mixture reduced by a maximum of 23.4%. • Glass microsphere negatively affected the road performances of asphalt mixture. To decrease the solar radiation heat entering the pavement, glass microsphere (GM) was selected as filler to replace limestone mineral filler (LMF) to improve the thermal resistance of asphalt mixture. The influence of GM on the thermal performance of asphalt pavement was studied by testing the thermal conductivity of asphalt mixture. It is found that the thermal conductivity could be reduced by 23.4%, which was beneficial to improve the cooling effect of asphalt pavement. A series of test, including dynamic repeated creep test, three-point bending test, dynamic modulus test and semi-circular bending test, were used to evaluate the influence of GM on the deformation resistance, low-temperature cracking resistance, dynamic performance and fatigue life of asphalt mixture. The results show that replacing LMF with GM negatively affected the above road performances of asphalt mixture. In further studies the actual rutting resistance of asphalt pavement with GM should be investigated by considering the cooled pavement structure and the elastic/creep performances of asphalt mixture. [ABSTRACT FROM AUTHOR]

• Glass microsphere was used to prepare thermal resistance asphalt mixture. • The thermal conductivity of asphalt mixture reduced by 23.8%. • The internal temperature of the thermal resistance pavement reduced. • The rutting depth of the middle and bottom layers reduced by a maximum of 8.5%. In this paper, glass microsphere (GM) was used to prepare thermal resistance asphalt mixture (TRAM) by replacing limestone mineral filler (LMF). The mixture was applied in the top layer of asphalt pavement to decrease the solar radiation transferring into asphalt pavement. The thermal, elastic and creep parameters of TRAM were obtained using a series of laboratory tests. Based on the above parameters, the heat transfer and rutting models of thermal resistance asphalt pavement (TRAP) were established. The results show that completely replacing LMF with GM in asphalt mixture resulted in thermal conductivity decreasing by 23.8% and specific heat capacity increasing by 10.6%. Compared with control asphalt pavement, the heat absorption of the designed pavement at the depth of 4 cm decreased by a maximum of 5.5% and the maximum temperature reduced up to 1.7 °C (at 12:00 p.m.). The cooling effect of thermal resistance pavement was verified by an indoor irradiation test. The rutting depth of the middle and bottom layers in the TRAP reduced by a maximum of 8.5% after 500 thousand times of standard axis load were applied. Due to the excellent thermal resistance effect, GM can be used to reduce the internal temperature of asphalt pavement and improve the rutting resistance of asphalt pavement. [ABSTRACT FROM AUTHOR]

The Yangtze River deepwater channel in the downstream of Nanjing China is the largest water transport project. It necessitates an effective ecological risk assessment of sediment–bound heavy metals driven by construction of the Yangtze River ship channel. We conducted a three–year field studies to investigate levels of heavy metals (Hg, Cd, Pb, Cu, and Zn), pH, and total phosphorus in sediments, as well as diversity of zoobenthos, phytoplankton, and zooplankton along the Taichang–Nantong reaches of the Yangtze River. Results showed that high–concentrations of Pb is at 130.62 mg/kg and of Hg is at 0.88 mg/kg in the sediments, which mainly emitted from the power electronics, power systems, and the hydrocarbon–based fuel combustion via principal component analysis. Based on optimized contamination indices for metals, we should consider their ecological risks when the potential ecological risk factor (E r i) of Hg is up to 210 in the basin. The channel construction resulted in significantly increasing concentrations and ecological risks of heavy metals at the lower reaches. Meanwhile, the community structure of aquatic organisms changed and the investigated species richness decreased significantly from 78 to 47 during the project. Through redundancy analysis, more significant variances of the plankton species richness (55% and 22%) were attributed to E r i of heavy metals and their combined risk index as compared with both planktonic and benthic organisms (52% and 17%). Moreover, the species density of both Melosira granulata and Navicula sp., major phytoplankton species in the basin, were significantly negatively correlated to Pb and Hg in sediments. Plankton was more sensitive indicators than zoobenthos due to the ability of plankton to reactivate and bioaccumulate sediment–bound heavy metals. This study innovatively warned management to control river engineering–induced ecological risks of metals in sediments and revealed their potential risk pathway of ingestion by sensitive plankton. Image 1 • Both pollution sources and toxicity mechanisms were identified to control risks. • Heavy metal risks were evaluated based on optimized ecological risk factors. • Ship channel construction cause impacts of heavy metals on aquatic ecosystem. • Community structural change was linked to risks posed by Hg and Pb in sediments. • Plankton were more sensitive than zoobenthos by ingestion of metals in sediments. [ABSTRACT FROM AUTHOR]

Stabilizers are commonly employed in SBS-modified asphalt, yet their specific impact on aging behavior remains ambiguous. Past studies have not agreed on their role and have primarily examined effects on the SBS polymer phase, neglecting asphalt phase influences. Understanding these interactions is essential for aging mechanisms and rejuvenation strategies. To solve this issue, this study compared three types of asphalt to analyze their properties during aging. Microscopic tests comprising morphology, chemical structure, and molecular weight analyses with nine quantitative indicators were conducted, and the distinct influences of stabilizers on asphalt and SBS polymer phases were elucidated. The results revealed that the change rate in the physical properties of SBS-modified asphalt during aging decreases with sulfur addition, rheological parameters indicated that sulfur predominantly protects the polymer network structure from degradation during short-term aging. Furthermore, stabilizers had no explicit impact on the carbonyl index but could delay the generation of asphaltene molecules during aging, the change rates of asphaltene% were 1.65% without stabilizers and 12.36% with them after TFOT (Thin film oven test) aging. Stabilizers also notably mitigated polymer degradation and exhibited beneficial effects even during PAV (Pressure aging vessel) aging. The overall findings contribute to a clearer understanding of the complex interplay among the various components of SBS-modified asphalt, such as base asphalt, SBS modifiers, and stabilizers, providing theoretical insights into aging mechanisms and rejuvenation strategies involving stabilizers. • The role and contributions of stabilizers in the aging process of SBS-modified asphalt thoroughly were analyzed. • The distinct effects of stabilizers on the asphalt phase and polymer phase after aging were examined. • Stabilizers could delay the generation of asphaltene molecules during aging. [ABSTRACT FROM AUTHOR]

• Proposed a simple and un-fluorinated superhydrophobic modification method for CNTs. • A modified CNTs/ epoxy coating with water contact angle of 151° was prepared on concrete surface. • The coating temperature rapidly increased from −10 ℃ to 81 ℃ under one sunlight intensity. • The freezing time of water droplets on the concrete surface had been extended from 55 s to 680 s. The problem of easy icing and difficult anti-icing on concrete pavement has prompted using superhydrophobic coatings as a potential solution. However, the coatings are prone to wetting failure after repeated icing-deicing cycles. In this study, a superhydrophobic and photothermal coating consisting of unfluorinated modified-carbon nanotubes (M-CNTs) and commercial epoxy is constructed by a simple spray process on concrete for anti-icing. Incorporating M-CNTs imparts the coating with exceptional superhydrophobic and photothermal characteristics, endowing the coating surface with excellent deicing under sunlight irradiation. The contact angle of the coating reaches 151° at −10 °C, and the freezing time extends from 55 s to 680 s. Under one sunlight intensity, the coating temperature rapidly increases from −10 ℃ to 81 ℃, and the ice changes from solid to liquid. It effectively acts as a barrier between water and the concrete surface, making it highly suitable and valuable in practical applications. [ABSTRACT FROM AUTHOR]

Since the correlation between the meso-structure composition and force chain transmission of asphalt mixtures, it has a significant impact on the evaluation and utilization of their material properties. Based on the discrete element method, this paper studied the internal force chains transmission mechanism of asphalt mixture under indirect tensile mode, and quantitatively analyzed the composition and distribution of the force chains. An aggregate template library for asphalt mixture was constructed using image segmentation and clump generation algorithm. Indirect tensile simulation was achieved by assigning relevant parameters, indicating a good correlation with laboratory tests. The tensile and compressive chain fields inside asphalt mixtures were visualized and characterized. The concept of strong and weak force chains was proposed, and statistical methods was used to analyze the strength, distribution, and evolution of force chains. The force transfer mechanisms of different components of asphalt mixtures have been elucidated, providing a research tool for their structural design and performance evaluation. • The aggregate template library was constructed within PFC3D. • Virtual indirect tensile test was built to analyze mechanical property. • The probability and distribution of the force chains were proposed. • The evolution law of the force chains was clarified. [ABSTRACT FROM AUTHOR]

10.1007/s10600-012-0380-4 12 Afaq S, Fatima I, Inamullah F, Khan S, Kazmi MH, Malik A, Tareen RB, Ali MS, Farhad MZ, Abbas T. Chem. Nat. Today, a total of 14 compounds was isolated from the plant for the first time, and compound B 14 b was isolated from I Clematis i genus for the first time. Compd. 2015; 51: 47. 1:CAS:528:DC%2BC2MXitVGgtr4%3D. 10.1007/s10600-015-1200-4 15 Kizaibek M, Cao P, Gu ZB, Bahetjan D, Jielile J. Chem. Nat. [Extracted from the article]

Shenling Baizhu San (SBS) is commonly employed to improve gastrointestinal dysfunction in patients with ulcerative colitis (UC) in China. SBS combined with mesalamine has been demonstrated to result in improve its curative effects without increasing any adverse reactions, but the underlying mechanism remains unclarified. Our study aimed to illuminate the potential therapeutic effects and mechanisms of SBS, which is a medicine complementary to mesalamine, in the treatment of UC. A prospective cohort study was conducted to evaluate the efficacy of SBS as a complementary medicine to mesalamine for patients with UC (n = 48). The patients in the control group (n = 24) were given mesalamine alone, whereas those in the experimental group were administered mesalamine combined with SBS. The therapeutic outcome was assessed at 8 weeks. The structures of the gut microbiota (GMB) were characterized by 16S rRNA sequencing, and the microbial tryptophan metabolites were analyzed by UPLC–MS/MS to investigate the mechanism through which SBS achieves its effects. Our results showed that the combination of SBS and mesalamine could significantly improve the clinical signs of UC by achieving mucosal healing and relieving colon damage. Interestingly, the combination of SBS and mesalamine could alter the GMB structures and increase the microbial levels of tryptophan metabolites, including indole-3-propionic acid and indole-3-acetic acid. SBS combined with mesalamine is effective in improving the clinical and endoscopic outcomes of patients with UC. SBS, as a complementary therapy to conventional treatment, alleviates UC via the GMB-tryptophan metabolite axis. [Display omitted] • SBS combined with mesalamine is effective in improving the clinical and endoscopic outcomes of patients with UC. • SBS combination therapy improves gut microbiota diversity and abundance in UC patients. • SBS, as a complementary therapy to conventional treatment, alleviates UC via the GMB-tryptophan metabolite axis. [ABSTRACT FROM AUTHOR]