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Grouting technology is the primary method for repairing cracks in earthen sites. However, there has been a long-standing lack of effective methods for evaluating grouting effectiveness. This paper proposes a field evaluation method based on P-wave velocity. This method explicitly discusses two scenarios where the P-wave velocity of the grout is either higher or lower than that of the soil, using the depth ℎ of the "hypothetical crack" as the evaluation indicator. The experimental results indicate that specimens with 20% and 40% defects show increases in ℎ values of 0.0113 m and 0.0166 m, respectively. Laboratory tests have demonstrated that this method can accurately evaluate grouting effectiveness and is not affected by the P-wave velocity of the soil. The application of this evaluation method to three typical earthen sites resulted in more reliable and easily quantifiable evaluation outcomes. By considering the width of grout, the method provides a more intuitive comparison of reparation effectiveness. The study demonstrates the feasibility of the proposed method, thereby facilitating effective crack reparation in earthen sites. [ABSTRACT FROM AUTHOR]

Saturated orthogonal array is an important type of fractional factorial designs in experimental design. On the basis of guaranteeing orthogonality, it maximizes the number of factors and saves the cost of experiments. Therefore, it is increasingly used in practical experiment. For quantitative factors, the minimum β-aberration criterion is suitable for selecting good designs under a polynomial model. However, construction methods of designs with less β-aberration have not been fully investigated. In this article, we apply the Rao-Hamming method to construct a class of three-level saturated orthogonal arrays, and perform a special level permutation on the designs of the Rao-Hamming construction, which makes the resultant designs mirror-symmetric ones. Furthermore, we analyze the distribution of elements in each row and among all possible pairs of rows of the mirror-symmetric designs, and discuss some properties of the β-wordlength pattern for three-level mirror-symmetric designs constructed by the Rao-Hamming method. In addition, we provide the explicit expressions of β3 and β4 for three-level mirror-symmetric designs, which can reduce the computational complexity of the β-wordlength pattern, and provide an effective idea for finding designs under the minimum β-aberration criterion. Finally, numerical examples are used to illustrate and verify the results. [ABSTRACT FROM AUTHOR]

Catalyst support morphology strongly influences its surface and structural properties, therefore, may have a significant impact on their reactivity in heterogeneous catalysis. Herein, the Pd/In 2 O 3 /CeO 2 -x (loaded with 1 wt% Pd and In 2 O 3) catalysts with different morphologies of rods(r), cubes(c) and irregularity(w) shapes were prepared by hydrothermal method and impregnation method. At temperature of 275–425 °C, as-prepared catalysts were evaluated for hydrogen production from methanol steam reforming (MSR). The activity data showed the outstanding performance of the rod-shaped Pd/In 2 O 3 /CeO 2 catalysts, exhibiting the complete conversion of methanol and particularly low CO (1.3%) at 375 °C. The structural properties and physicochemical of Pd/In 2 O 3 /CeO 2 -x with different morphologies were characterized by means of X-ray diffraction (XRD), high resolution transmission microscopy (HR-TEM), CO pulse chemisorption, X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption of methanol (CH 3 OH-TPD). Activity data and catalyst characterization results correlated, and indicated that the excellent reactivity for the rod-shaped Pd/In 2 O 3 /CeO 2 catalysts in MSR is ascribed to the large particle size of palladium nanoparticles and the abundant oxygen vacancies induced by the strong interaction between Pd, In and Ce. HR-TEM results revealed that rod-like CeO 2 mainly expose (110) crystalline surface with high mobility of surface oxygen and possess the most abundant surface oxygen vacancies with the low formation energy, facilitating the formation of active species of Pd0 on catalyst surface, and promoting the activation and adsorption of methanol and water molecules. Furthermore, the rod-shaped Pd/In 2 O 3 /CeO 2 catalysts showed excellent reactivity and stability in MSR for 30 h, demonstrating its potential of being used as catalysts in methanol steam reforming in PEMFC systems. Table of Contents. [Display omitted] • The morphology of CeO 2 greatly influence the catalytic performance over Pd/In 2 O 3 catalysts. • Nanorod-like Pd/In 2 O 3 /CeO 2 -r catalysts with mainly exposed (110) crystal facet exhibit high MSR activity. • The large size of palladium nanoparticles facilitates H 2 dissociation and methanol activation. • The synergistic effect between Pd/In 2 O 3 and of CeO 2 dominate the MSR catalytic performance. • The number of oxygen vacancies are vital for superior performance of Pd/In 2 O 3 /CeO 2 -r catalysts. [ABSTRACT FROM AUTHOR]

Suppose the intermediate coupler of a rail vehicle is unstable during the collision process and loses its connection and energy dissipation functions. In that case, it will significantly reduce the performance of the train crashworthiness function and increase the risk of train derailment. This paper aims to establish a refined finite element model (RFEM) that can simulate the buckling behaviour and investigate the bending resistance and buckling instability characteristics of the intermediate coupler, and the accuracy of the RFEM was verified by quoting the results of an existing intermediate coupler impact test. The results demonstrated that the proposed coupler modelling method could better simulate the energy absorption characteristics and unstable behaviour. Compared to the test results, the differences in the initial crushing force, maximum longitudinal compression displacement, minimum crushing force, and maximum crushing force were 6.5%, 1.3%, 3.6%, and 6.5%, respectively. Within the allowable range of parameters, the maximum bending force linearly increased with an increase in the initial longitudinal compression displacement. As the pitch or yaw angle increased, the longitudinal buckling load of the coupler linearly decreased and became more sensitive to the pitch angle. When pitch and yaw angles existed simultaneously, the longitudinal buckling load was further reduced. [ABSTRACT FROM AUTHOR]

With the development of modern electronic countermeasure technology, the fight between radar jamming and anti-jamming has become increasingly fierce. Experts have done a lot of highly effective work on radar anti-jamming performance. However, the emergence of various new complex interferences has rendered existing methods unable to meet the needs. In this manuscript, we consider the measurement and evaluation method of radar anti-jamming effectiveness based on principal component analysis and machine learning. Firstly, taking into account the diversity of variables in radar countermeasure experiments and the complexity of constraints between variables, we propose a bipartite covering array for the experimental scheme, which requires that each level combination of any radar parameter and jammer parameter occurs at least once, to ensure the rationality of the experiments. Secondly, according to the characteristics of multiple jammers and the analysis of impacts on radar performances, we combine the existing indicators and use the principal component analysis method to obtain two comprehensive indicators, which better reflect radar performances. Finally, we select the best model as a prediction for radar comprehensive indicators by comparing several machine learning algorithm models, including classification and regression tree, random forest, xgboost, and SVM. Additional experiments verify the effectiveness of the resulted model. [ABSTRACT FROM AUTHOR]

Four new phenolic glycosides lepidiumosides A–D (1–4) were isolated from the water extract of the seeds of Lepidium apetalum Willd. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI-MS, 1D and 2D NMR) analyses. In addition, these compounds were evaluated for their protective effects impaired by H2O2 in H9c2 cells, suggesting that compounds 1–4 exhibited protective effects against H2O2-induced cardiotoxicity. [ABSTRACT FROM AUTHOR]

On the premise of following the concept of culture heritage conservation, the technique of wooden bolt anchorage plays an important role in the conservation of rammed earthen sites. The existing researches on single anchoring cannot reflect the mechanical behaviors of an anchor group. To solve this problem, this study proposes a load-transfer method achieved by a universal joint combined with a load-bearing platform. Three rammed earth models were tested by continuous loading, with embedded length, bolt interval, and margin as variables. The failure mode, ultimate pulling resistance, load–displacement relationship, and interfacial strain distribution of the anchorage system were analyzed. Results show that the two bolts present sequential failure. Meanwhile, the failure of wooden bolts is not in a single mode; instead both interfacial debonding and soil-bearing capacity loss were observed in soil at the same time. The bolts are mostly in plastic-slipping state under working conditions. The strain is unevenly distributed at the bolt—grout interface and highest near the loading side. Spacing effect and marginal effect are important factors affecting the pulling resistance of two bolts, and their importance is higher than the quality of a single bolt. In addition, numerical simulations on behaviors of two wooden bolts, considering the interval distance, margin distance, embedment length, and layered property of rammed earth, were established by "interface" element, which supplemented and expanded the model test results. Results of this paper could provide deeper understanding of the macroscopic performance and internal mechanism of a two-bolts group. [ABSTRACT FROM AUTHOR]

Due to the modulation of tiny frequency offset on the array elements, a frequency diverse array (FDA) jammer can generate multiple range-dimension point false targets, and many deception jamming methods against SAR using an FDA jammer have been studied. However, the potential of the FDA jammer to generate barrage jamming has rarely been reported. In this paper, a barrage jamming method against SAR using an FDA jammer is proposed. To achieve two-dimensional (2-D) barrage effect, the stepped frequency offset of FDA is introduced to generate range-dimensional barrage patches, and the micro-motion modulation is employed to increase the extent of barrage patches along the azimuth direction. Mathematical derivations and simulation results demonstrate the validity of the proposed method in generating flexible and controllable barrage jamming. [ABSTRACT FROM AUTHOR]

Designated as a world heritage site by UNESCO in 1987, the Mogao Grottoes is famous for its cultural relics, in particular, the superb murals and painted sculptures. Moisture has been confirmed as the most active factor that could result in mural diseases. Therefore, ascertaining the moisture distribution of the cliff is of great significance for preventing the deterioration of murals and painted sculptures. In this study, a multi-electrode resistivity survey is applied atop the cliff of Mogao Grottoes. By deploying survey lines in two main study areas, the moisture distribution of the cliff is reflected by the resistivity profiles qualitatively. The results show that there is a mutually verifying relationship between the resistivity profiles and the water content of the exploratory well. In general, the resistivity of the cliff body is low in the distribution range of 1–300 Ω·m. It shows that the moisture content of these gullies atop the cliff is even lower. Besides, four potential danger areas are determined on the cliff face. Murals in these caves, which are excavated in these areas, will suffer more serious deterioration due to the moisture migration. The result also ascertains that the resistivity of the cliff could determine the moisture distribution inside the cliff. Moreover, this study can provide a firm scientific basis for protecting the valuable murals and painted sculptures in the caves. [ABSTRACT FROM AUTHOR]

• Low concentration coal mine methane is used as fuel for SOFCs. • Ce-doped LCSFN perovskite is employed as an anode internal reforming catalyst. • Ce-doped LCSFN can enhance the fuel conversion efficiency and coking tolerance of anode. • Single cells show 100 h-long-term stability fueled by low concentration coal mine methane. Solid oxide fuel cells (SOFCs) possess the potential to directly utilize abundant low concentration coal mine methane for power generation, which is crucial for energy conservation and reducing greenhouse gas emissions. Herein, Ce-doped La 0.55 Ce 0.15 Sr 0.3 Fe 0.9 Ni 0.1 O 3-δ (LCSFN) perovskite is firstly employed as an anode internal reforming catalyst to enhance the electrochemical performance, stability, and resistance against carbon deposition in SOFCs. The results demonstrate that Ni-Fe alloy nanoparticles can be effectively precipitated from LCSFN under reducing atmosphere, thereby significantly promoting the partial oxidation reaction of methane while preventing direct contact between methane and Ni particles for the anode. The anode-supported single cells demonstrated exceptional electrochemical performance using a composite catalytic layer consisting of LCSFN-Ce 0.9 Gd 0.1 O 2-δ (LCSFN-GDC). At 800℃, the utilization of both H 2 and 16 %CH 4 -1 %O 2 -N 2 resulted in the attainment of maximum power densities (MPD) measuring 881.66 mW·cm−2 and 824.69 mW·cm−2, respectively, with the recorded values for polarization resistance were 0.32 and 1.16 Ω·cm2. Additionally, the single cells equipped with LCSFN-GDC internal reforming catalytic exhibit remarkable resistance to carbon deposition, maintaining stable performance for a duration of 100 h using 16 %CH 4 -1 %O 2 -N 2. These findings underscore the efficacy of methane catalysts in SOFCs, as it not only enhances power generation efficiency through using internal reforming catalyst but also ensures long-term stability by mitigating carbon-related issues. [ABSTRACT FROM AUTHOR]

The construction of hardwood kraft lignin (HKL)-based carbon fibrous aerogels (LCAs) for practical application still faces significant challenges. In this work, we proposed to enhance LCAs through the utilization of hydrogen-bonding interactions and π-π interactions. Self-supported LCA/graphene oxide (GO) composites were prepared based on the adhesion of HKL ultrafine fibers and GO, taking advantage of the strong interaction between HKL and GO. The morphology, thermal behavior, chemical structure and crystalline structure of LCA/GO composites were systemically investigated and discussed. Results suggested that HKL ultrafine fibers and GO formed a cohesive whole carbonization due to the influence of hydrogen-bonding and π-π interaction. The prepared LCA/GO composites exhibited outstanding rate capability and high oil/seawater separation flux with their three-dimensional hierarchical channel structures. The specific capacitance of the LCA/GO 5.0 electrode was 152 F g−1 at 0.5 A g−1 and 94 F g−1 at 10 A g−1, respectively, while maintaining a retention rate of 113 % after 2000 cycles. The adsorption capacity of the LCA/GO 7.5 composite reached up to 55.9 g g−1 and its oil/seawater separation flux was as high as 12,335 L m−2 h−1. The formation strategy, sustainable concept and excellent properties presented in this work will give some inspiration for the preparation of self-supported aerogels as well as their applications in compressible supercapacitors and oil/seawater separation. • Self-supported LCA was prepared without the use of coupling agents. • The specific capacitance of LCA/GO 5.0 electrode under 10 A g−1 was up to 94 F g−1. • LCA/GO 5.0 electrode exhibited a capacitance residual ratio of 113 % after 2000 cycles. • The oil/water separation flux of LCA/GO 7.5 composite was up to 16,447 L m−2 h−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Co/Mo co-doped NVP composite with unique cluster porous structure is prepared. • Doping Co2+ provides p-type effect, broadens ionic channel and reinforces crystal structure. • Mo6+ doping results in n-type effect and brings more electrons to increase electronic concentration. • Coral cluster porous structure increases contacting areas with electrolyte and withstands the stress. • Ex-situ XRD/XPS/SEM analysis demonstrates the improved crystal stability of NVCMP0.15. Na 3 V 2 (PO 4) 3 (NVP) is suffered from poor conductivities and terrible structure stability. Herein, Co/Mo co-doped NVP with unique cluster porous structure is prepared. Notably, Co2+ replacing V3+ provides useful p-type effects, manufacturing more acceptor levels and generating equal hole carriers, which facilitates the ionic conductivity. Moreover, the larger ionic radius of Co2+ significantly enlarges the interplanar spacing to broaden ionic migration channel. The doped Co2+ can function as pillar ions to reinforce the crystal structure, further improving structure stability. Meanwhile, Moderate Mo6+ is introduced to keep charge balance, resulting in beneficial n-type doping effects, which can bring more electrons and increase the electronic concentration to speed up electronic conduction. Notably, a unique coral cluster porous structure is formed after controlling the added Co/Mo contents. This distinctive morphology allows active materials expose more contact areas with electrolyte to enhance infiltration effects, increasing the active sites to release more reversible capacity. Moreover, the porous construction withstands the stress resulting from the volume contraction during Na+ de-insertion. Comprehensively, NVCMP0.15 exhibits a value of 90.7 mAh g−1 at 50C and retains 68.5 mAh g−1 after 2000 cycles with retention ratio of 75.52 %. Ex-situ XRD/XPS/SEM after cycling indicate great improvements in crystal stability of NVCMP0.15. [ABSTRACT FROM AUTHOR]

Five new triterpenoids, oenotheralanosterols C-G (1–5), with seven known triterpenoidcompounds, namely 2α,3α,19α-trihydroxy-24-norurs4,12-dien-28-oic acid (6), 3β,23-dihydroxy-1-oxo-olean-12-en-28-oic acid (7), remangilone C (8), knoxivalic acid A (9), termichebulolide (10), rosasecotriterpene A (11), androsanortriterpene C (12), were extracted and separated from the dichloromethane part of Oenothera biennis L. The anti-pulmonary fibrosis activities of all the compounds against TGF-β1-induced damage tonormal human lung epithelial (BEAS-2B) cells were investigated in vitro. The results showed that compounds 1–2, 6, 8, and 11 exhibited significant anti-pulmonary fibrosis activities, with EC50 values ranging from 4.7 μM to 9.9 μM. [ABSTRACT FROM AUTHOR]

The finite step length (FSL) method is extensively used for structural reliability analysis due to its robustness and efficiency compared with traditional Hasofer–Lind and Rackwitz–Fiessler (HL-RF) method. However, it may generate a large computational effort when it faces some complex nonlinear limit state functions. This study explains the basic reason of inefficiency of the FSL method and proposes an enhanced finite step length (EFSL) method to improve the ability for solving complex nonlinear problems, and then apply it to reliability-based design optimization (RBDO). The tactic is to present an iterative control criterion to compensate for the deficiency of the FSL method in the oscillation amplitude criterion, which solves the problem of large computational effort caused by unchanged step length during the iterative process. Then, a comprehensive step length adjustment formula is presented, which can adaptively adjust the step length to achieve fast convergence for limit state functions with different degrees of nonlinearity. Following that, the proposed method is combined with the double loop method (DLM) to improve the efficiency and robustness for solving complex RBDO problems. The robustness and efficiency of the proposed method compared to other commonly used first-order reliability analysis methods are demonstrated by five numerical examples. In addition, four design problems are used to validate the proposed EFSL-based DLM which is effective for solving complex nonlinear RBDO problems. [ABSTRACT FROM AUTHOR]

Objective. Synthetic transmit aperture (STA) ultrasound imaging is well known for ideal focusing in the full field of view. However, it suffers from low signal-to-noise ratio (SNR) and low frame rate, because each transducer element must be activated individually. In our previous study, we encoded all the transducer elements with partial Hadamard matrix and reconstructed the complete STA dataset with compressed sensing (CS) algorithm (CS-STA). As all the elements are activated in each transmission and the number of transmissions is smaller than that of STA, this method can achieve higher SNR and higher frame rate. Its main drawback is the time-consuming CS reconstruction (∼hours). In this study, we propose to accelerate the complete STA dataset reconstruction with minimal l 2-norm least squares method. Approach. Partial Hadamard apodized plane wave (PW) transmissions were performed to acquire the PW dataset. Thereafter, the complete STA dataset can be reconstructed from the PW dataset with minimal l 2-norm least squares method. Due to the orthogonality of partial Hadamard matrix, the minimal l 2-norm least squares solution can be easily calculated. Main results. The proposed method is tested with simulation data and experimental phantom and in-vivo data. The results demonstrate that the proposed method achieves ∼5 × 103 times faster reconstruction speed than CS algorithm. The simulation results demonstrate that the proposed method is capable of achieving the same accuracy as the conventional CS-STA method for the STA dataset reconstruction. The simulations, phantom and in-vivo experiments show that the proposed method is capable of improving the generalized contrast-to-noise ratio (gCNR) and SNR with maintained spatial resolution and fewer transmissions, compared with STA. Significance. In conclusion, the improved image quality and reduced computational time of LS-STA pave the way for its real-time applications in the clinics. [ABSTRACT FROM AUTHOR]

The change of microvasculature is associated with the occurrence and development of many diseases. Ultrafast power Doppler imaging (uPDI) is an emerging technology for the visualization of microvessels due to the development of ultrafast plane wave (PW) imaging and advanced clutter filters. However, the low signal-to-noise ratio (SNR) caused by unfocused transmit of PW imaging deteriorates the subsequent imaging of microvasculature. Nonlocal means (NLM) filtering has been demonstrated to be effective in the denoising of both natural and medical images, including ultrasound power Doppler images. However, the feasibility and performance of applying an NLM filter on the ultrasound radio frequency (RF) data have not been investigated so far. In this study, we propose to apply an NLM filter on the spatiotemporal domain of clutter filtered blood flow RF data (St-NLM) to improve the quality of uPDI. Experiments were conducted to compare the proposed method with three different methods (under various similarity window sizes), including conventional uPDI without NLM filtering (Non-NLM), NLM filtering on the obtained power Doppler images (PD-NLM), and NLM filtering on the spatial domain of clutter filtered blood flow RF data (S-NLM). Phantom experiments, in vivo contrast-enhanced human spinal cord tumor experiments, and in vivo contrast-free human liver experiments were performed to demonstrate the superiority of the proposed St-NLM method over the other three methods. Qualitative and quantitative results show that the proposed St-NLM method can effectively suppress the background noise, improve the contrast between vessels and background, and preserve the details of small vessels at the same time. In the human liver study, the proposed St-NLM method achieves 31.05-, 24.49-, and 11.15-dB higher contrast-to-noise ratios (CNRs) and 36.86-, 36.86-, and 15.22-dB lower noise powers than Non-NLM, PD-NLM, and S-NLM, respectively. In the human spinal cord tumor, the full-width at half-maximums (FWHMs) of vessel cross Section are 76, 201, and $197 \mu \text{m}$ for St-NLM, Non-NLM, and S-NLM, respectively. The proposed St-NLM method can enhance the microvascular visualization in uPDI and has the potential for the diagnosis of many microvessel-change-related diseases. [ABSTRACT FROM AUTHOR]

To investigate the mechanical behavior of composite beams under pure torsion, considering the torsional contribution of the steel beam flanges, we established finite element models of I‐steel–concrete composite beams. The nonlinear material constitutive relationship of concrete and steel was adopted in the model, and we validated the relationship by tests. Afterward, parametric analyses were carried out to study the main factors affecting the torsional performance of the composite beam. Our primary investigation focused on the composite effects and load sharing ratio of the steel beam and the concrete slab under pure torsion. We established the formulas for obtaining the maximum shear stresses in the concrete slab and the steel beam based on the composite effects and superposition principle. From these tests and our calculations, we proposed a model defining the torsional bearing capacity and the torsional stiffness of the I‐steel–concrete composite beam; thus, the torsional contribution of the concrete slab and the steel beam were a primary concern in this research. Bearing capacity formulas are also proposed herein and are comparable with those in the literature, demonstrating that our formulas, with simple forms, are highly reliable when predicting the torsional behavior of the composite beam. [ABSTRACT FROM AUTHOR]

Purpose: As a typical chronic kidney disease (CKD), hypertensive nephrosclerosis (HN) is a common syndrome of hypertension, characterized by chronic kidney microvascular damage. Early diagnosis of microvascular damage using conventional ultrasound imaging encounters challenges in sensitivity and specificity owing to the inherent diffraction limit. Ultrasound localization microscopy (ULM) has been developed to obtain microvasculature and microvascular hemodynamics within the kidney, and would be a promising tool for the early diagnosis of CKD. Methods: In this study, the advantage of quantitative indexes obtained by using ULM (mean arterial blood flow speeds of different segments of interlobular arteries) over indexes obtained using conventional clinical serum (β2‐microglobulin, serum urea nitrogen, and creatinine) and urine (24‐h urine volume and urine protein) tests and ultrasound Doppler imaging (peak systolic velocity [PSV], end‐diastolic velocity [EDV], and resistance index [RI]) and contrast‐enhanced ultrasound imaging (CEUS; rise time [RT], peak intensity [IMAX], mean transit time [mTT], and area under the time‐intensity curve [AUC]) for early diagnosis of HN were investigated. Examinations were carried out on six spontaneously hypertensive rats (SHR) and five normal Wistar–Kyoto (WKY) rats at the age of 10 weeks. Results: The experimental results show that the indicators derived from conventional clinical inspections (serum and urine tests) and ultrasound imaging (PSV, EDV, RI, RT, IMAX, mTT, and AUC) do not show significant difference between hypertensive and healthy rats (p > 0.05), while the TTP of the SHR group (28.52 ± 5.52 s) derived from CEUS is significantly higher than that of the WKY group (18.68 ± 7.32 s; p < 0.05). The mean blood flow speed in interlobular artery of SHR (12.47 ± 1.06 mm/s) derived from ULM is significantly higher than that of WKY rats (10.13 ± 1.17 mm/s; p < 0.01). Conclusion: The advantages of ULM over conventional clinical inspections and ultrasound imaging methods for early diagnosis of HN were validated. The quantitative results show that ULM can effectively diagnose HN at the early stage by detecting the blood flow speed changes of interlobular arteries. ULM may promise a reliable technique for early diagnosis of HN in the future. [ABSTRACT FROM AUTHOR]

A large number of numerical simulations are required to design an energy absorption scheme for train crashworthiness, leading to low design efficiency in the early stage. Based on train collision dynamics theory and the finite element method, a dynamic finite element model of longitudinal train collision is established. According to the model, we studied the acceleration time-history characteristics during the train collision process, obtained the mean-peak ratio coefficient, and determined the calculation formula for the maximum mean acceleration of a longitudinal train collision. Through characteristic analysis of the vehicle acceleration, interface force, and other parameters during a longitudinal train collision, the calculation method of the mean acceleration was improved. The analysis shows that the maximum mean acceleration depends on two stages in the collision process: (1) the coupler action of the head vehicle: the mean-peak ratio coefficient of the head vehicle is 0.7 in this stage, and the mean-peak ratio coefficient of other vehicles is 0.43; (2) the coupler of the collision interface is cut off, and the energy absorption devices of the head vehicle or intermediate vehicle absorb energy; the mean-peak ratio coefficient of the vehicle is 0.93 in this stage. On this basis, a mathematical function is established describing the mean acceleration of the vehicle and the average crushing force of the coupler collapse tube and the energy-absorbing device. The calculation formula is obtained for the maximum mean acceleration of the longitudinal train collision, and the results are compared with the mean acceleration obtained by numerical simulation. The Kruskal–Wallis ANOVA multisample independent nonparametric test was conducted to verify the reliability of the calculation results in the 95% confidence interval. The calculation formula can be used to calculate the maximum mean acceleration in the energy allocation stage of train crashworthiness design to effectively improve the efficiency of train collision energy allocation. [ABSTRACT FROM AUTHOR]

Grout injection is an effective technique for repairing cracks in earthen sites. This study aims to address the challenges of Calcined Ginger Nuts (CGN)-based grout and enhance its engineering performance by investigating the compatibility of different superplasticizers. We examined the effects of Polycarboxylate Superplasticizer (PCE) and Naphthalene Superplasticizer (PNS) on the properties of CGN-based grout, focusing on fluidity, rheological properties, mechanical strength, volume stability, color difference, and pore structure. The engineering applicability of the optimized CGN-based grout with superplasticizers was assessed using COMSOL Multiphysics. The results show that fluidity increased with higher dosages of PCE and PNS. The grout containing these superplasticizers behaved as a shear-thinning fluid, following the power law model. Specifically, the consistency coefficient of grout with 0.5 wt% PCE and PNS decreased by 39.73% and 64.83%, respectively. Additionally, 2.9 wt% PCE and PNS reduced volume shrinkage rate by 6.86% and 6.27%, respectively. Initially, increasing the dosage of PCE and PNS improved compressive and flexural strength, but these properties later declined. XRD analysis revealed that PNS above 1.1 wt% and PCE weakened the hydration reaction, while both superplasticizers promoted carbonation. Mercury Intrusion Porosimetry (MIP) showed that 1.1 wt% PCE and PNS reduced the proportion of capillary pores by 13.79% and 10.11%, respectively. Based on these findings, 0.5 wt% PNS demonstrated the best compatibility with CGN-based grout, whereas PCE showed poor compatibility. Numerical simulations using COMSOL Multiphysics confirmed that 0.5 wt% PNS provided superior grouting effectiveness. Therefore, the CGN based grout with 0.5wt% PNS demonstrates excellent engineering performance and applicability. This study offers valuable insights into optimizing CGN-based grout for the preservation of earthen sites. [ABSTRACT FROM AUTHOR]

Twelve undescribed compounds, including five flavonoids and seven phenols, were isolated from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, including NMR spectroscopy and HRESIMS analysis. Their absolute configurations were elucidated by comparing their experimental and calculated ECD spectra. In the in vitro bioactive assay, all compounds were tested for their anti-asthmatic activities by releasing β -Hex in C48/80-induced RBL-2H3 cells. The β -Hex release rates of compounds 3 , 8 , 10 , and 11 were 0.8502 ± 0.0231, 0.8802 ± 0.0805, 0.7850 ± 0.0593, and 0.8361 ± 0.0728, respectively, suggesting that compounds 3 , 8 , 10 , and 11 have potential anti-asthmatic activities. Twelve undescribed compounds were isolated from the stems of E. equisetina and their anti-asthmatic activities were evaluated. [Display omitted] • Twelve undescribed compounds were isolated from the stems of E. equisetina. • Their structures were elucidated by NMR and mass spectrometry. • The absolute configurations were deduced by interpretation of ECD. • The anti-asthmatic activities of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

Study on the weathering characteristics of Niche of Sakyamuni Entering Nirvana at Dazu Rock Carvings is the first step of scientific conservation. Based on the in-depth investigation on the weathering characteristics of Niche of Sakyamuni Entering Nirvana, the weathering degree was measured and evaluated by means of the in-situ non-destructive surface hardness test and ultrasonic test. The results reveal that the weathering types of Niche of Sakyamuni Entering Nirvana consist of granular disintegration, salt efflorescence, scaling, blistering, cracking, missing parts, biological colonization, and water seepage. The weathering degree of the head and foot of the statues are higher than that of the chest and abdomen in the horizontal direction, and the weathering degree of the upper parts of the statues and the ground area are higher than that between them in the vertical direction. The results of surface hardness and ultrasonic velocity are in close accordance with the weathering degree of the statues. Sedimentary and structural characteristics of sandstone lay a material foundation for various weathering characteristics and degree. The research results pave the way for condition assessment, intervention decision-making, and preventative conservation of the studied statues. [ABSTRACT FROM AUTHOR]

This article presents a laboratory and field investigation of pull-out resistance of wood bolts in rammed earth heritages. The laboratory testing involved axial tensile tests of four grout specimens prepared in specially designed moulds using PS-F (Potassium Silicate solution-Fly ash) slurry to investigate the performance of anchors. The field testing involved pull-out tests of three wood anchors installed in rammed earth heritages by gravity grouting. Experiments reveal that the failure mode is the pull-out of bolt from grout and average skin friction resistance of bolt–grout interface is approximately 0.34MPa. Load–displacement curves and elastic–residual displacement derived from cyclic loading indicate such anchor system has strong ductility with small elastic deformation and large residual deformation. Bond collapse firstly occurs at the loaded end and then propagates towards the full bonded length. Bond stress distribution is not uniform along the bonded length. Maximum bond stress distributes at the range from 0.3 m to 0.4 m. Emergence of compressive strain in the interface reveals such anchor system enjoys the advantages of both tensile and compressive anchor types, which significantly differs from results from other regular bolts. The research conclusion makes scientific senses to traditional material and craft in rammed earth heritages. [ABSTRACT FROM PUBLISHER]

The work reported here is a systematic study to evaluate the compatibility of using PS-F (potassium silicate with high modulus – fly ash) slurry in the conservation of adobe structures. Firstly, the optimum mixing proportion (0.47) was determined by flow meter. Then the experimental program was divided into two parts: one part studied changes in physical and mechanical properties with increase in setting time by means of the measurement of moisture content, compressive and flexural strength, elastic-wave velocity, density, and porosity; the other part studied the durability of PS-F slurry through temperature and humidity cycles, freeze–thaw cycles, water stability, tensile testing, and alkali resistivity tests. The results show that the consolidation process with the slurry can meet the requirements of conservation applications and provide a timely anchoring force, and the slurry and soil mass of adobe-based structures have good compatibility in physical and mechanical properties. In addition, the slurry can strongly resist freeze–thaw cycles, temperature-moisture cycles, and tensile stress and has a relatively weak resistance to alkali solutions and water immersion. In conclusion, PS-F with a mixing ratio of 0.47 is a suitable slurry for conservation of adobe structures. [ABSTRACT FROM PUBLISHER]

Numerous cretaceous sandstone grottoes in Longdong area have been suffering from serious weathering, and the weathering is proceeding at a considerable rate, resulting in severe challenges for conservation practice. However, relatively little is known about the weathering behavior and mechanism of cretaceous sandstone in Longdong Area. In this study, cretaceous sandstone in North Grotto Temple was selected as a typical case, and the weathering characteristics from the surface to the interior in real environment were studied by field investigation and laboratory analysis (particle and pore size distribution, soluble salt content, microstructure, mineral and chemical composition). Cretaceous sandstones are mainly litharenite and feldspathic litharenite at the North Grotto Temple (NGT). Efflorescence and subflorescence were confirmed as the main weathering forms for litharenite and feldspathic litharenite, respectively. Sodium sulfate and sodium chloride observed from the SEM images were the most active soluble salts tend to accumulate at the certain depth below the surface (1 cm for litharenite and 3 cm for feldspathic litharenite). The salts migration kinetics inside the cliff were concluded based on the distribution of salts. The K-feldspar increased from the surface to the interior with the kaolinite, illite decreasing, indicating the corresponding alteration of K-feldspar in the surface layer. The weathering indexes indicated that the weathering degree along the depth was nonlinear, whereas the weathering degree was firstly increased and then decreased from the surface to the interior. The experimental results in this study can provide a better understanding for the weathering mechanisms of cretaceous sandstone in Longdong Area. • The weathering mechanism of Cretaceous sandstone from the surface to the interior was investigated; • Nonlinear deterioration pattern of Cretaceous sandstone from the surface to the interior is obtained; • The salts migration kinetics inside the vertical cliff were concluded. [ABSTRACT FROM AUTHOR]

In this study, calcined ginger nuts (CGN) grouts admixed by fly ash (F) and quartz sand (S) was investigated on its suitability for anchoring use in earthen sites. According to requirement for the consistency of grout, the mix proportions were determined with 0.45 for CGN_F, 0.33 for CGN_S and 0.35 for CGN_F_S, by mass, to study their physical and mechanical property and durability. Test results indicated that use of fly ash can prolong the initial setting time of grout and admixture by fly ash and quartz sand leaded to lowest density and shrinkage, higher porosity, and highest strength. Accelerated aging tests indicated that admixture by fly ash led to a high resistance to fluctuation of temperature and humidity, sulfate attack and alkali environment; meanwhile, admixture by quartz sand resulted in high resistance to freeze-thaw action and water environment. As a compromise, CGN_F_S can get predominant durability. The paper shows that CGN_F_S grout is basically compatible to earthen sites and suitable for anchoring use in the conservation of earthen sites in terms of workability and durability. [ABSTRACT FROM AUTHOR]

• In-phase/quadrature (IQ) data were used to accelerate CS-STA. • IQ-domain CS-STA maintains high image quality of conventional RF-domain CS-STA. • CS-STA obtains similar resolution, higher contrast and higher frame rate, compared with STA. • More compatible with clinical ultrasound system than RF-domain CS-STA. Compressed sensing-based synthetic transmit aperture (CS-STA) was previously proposed to recover the full radio-frequency (RF) channel dataset of synthetic transmit aperture (STA) from that of a smaller number of randomly apodized plane wave (PW) transmissions. In this way, the imaging frame rate (FR) and contrast are improved with maintained spatial resolution, compared with those of STA. Because CS-STA reconstruction is repeated for all receive elements and RF samples (with a high sampling frequency), the recovery of STA dataset in RF domain is time-consuming. In the meantime, a large amount of RF data needs to be transferred and stored, resulting in an increase of system complexity and required memory space. In this study, CS-STA is extended to in-phase/quadrature (IQ) domain (with lower sampling frequency) for the recovery of baseband STA IQ dataset to accelerate the CS-STA reconstruction by reducing the amount of data to be processed. More importantly, CS-STA reconstruction using IQ data is of practical importance, as clinical ultrasound systems typically record baseband IQ signal instead of RF signal. Simulations, phantom and in vivo experiments verify the feasibility of CS-STA in IQ domain for the recovery of STA dataset. More specifically, CS-STA using IQ data achieves similar image quality and appreciably improves reconstruction speed (by ∼3 times) compared with that using RF data. These findings demonstrate that IQ-domain CS-STA is capable of relieving the computational and storage burdens, which may facilitate the implementation of CS-STA in practical ultrasound systems. [ABSTRACT FROM AUTHOR]

Small specimen test techniques (SSTTs), developed for scarce materials, industrial products, in-service equipment, etc., could be challenging to obtain sufficient materials for routine testing. This review focuses on the research on millimeter- and micron-scale SSTTs of metallic materials in the past decade. Mainstream small specimens are divided into similarity, penetration, and semi-penetration. Representative tests of the above three categories are analyzed in detail, including the small tensile test, small punch test, and indentation test. The macro- or micro-correlation methods of deformation and failure parameters between the SSTTs and conventional tests are discussed, including Young's modulus, yield strength, ultimate tensile strength, damage evolution, fracture strain, and the stress–strain full-history relationships. Meanwhile, the extensive requirements for material testing are also considered, such as anisotropy and strain rate, temperature, and stress triaxiality sensitivities. The characteristics and modification strategies of the SSTTs are described from the aspects of size effects, inhomogeneous structures, and manufacturing defects. Finally, this paper discusses the application of SSTTs in forging, stamping, welding, and additive manufacturing and highlights the potential development directions of SSTTs. [ABSTRACT FROM AUTHOR]

The growth status of winter wheat seedlings during the greening period is called the seedling situation. Timely and accurate determinations of the seedling situation type are important for subsequent field management measures and yield estimation. To solve the problems of low-efficiency artificial classification, subjective doping, inaccurate classification, and overfitting in transfer learning in classifying the seedling condition of winter wheat seedlings during the greening period, we propose an improved ConvNeXt winter wheat seedling status classification and identification network based on the pre-training–fine-tuning model addressing over-fitting in transfer learning. Based on ConvNeXt, a SETFL-ConvNeXt network (Squeeze and Excitation attention-tanh ConvNeXt using focal loss), a winter wheat seedling identification and grading network was designed by adding an improved SET attention module (Squeeze and Excitation attention-tanh) and replacing the Focal Loss function. The accuracy of the SETFL-ConvNeXt reached 96.68%. Compared with the classic ConvNeXt model, the accuracy of the Strong class, First class, and Third class increased by 1.188%, 2.199%, and 0.132%, respectively. With the model, we also compared the effects of different optimization strategies, five pre-training-fine-tuning models, and the degree of change in the pre-trained model. The accuracy of the fine-tuning models trained in the remaining layers increased by 0.19–6.19% using the last three frozen blocks, and the accuracy of the pre-trained model increased by 3.1–8.56% with the least degree of change method compared with the other methods. The SETFL-ConvNeXt network proposed in this study has high accuracy and can effectively address overfitting, providing theoretical and technical support for classifying winter wheat seedlings during the greening period. It also provides solutions and ideas for researchers who encounter overfitting. [ABSTRACT FROM AUTHOR]

With the emergence of Level 4 automated vehicles, it is necessary to investigate the impact of these vehicles on mode choice. Previous studies have looked at the potential benefits and drawbacks of automated vehicles, but there has been little research done on how these vehicles will impact individuals' travel behaviors. This paper proposes a needs‐based approach to study the impact of Level 4 automated vehicles on mode choice. The approach takes into consideration the travel needs of different individuals and their willingness to adopt new technologies. Through a stated preference survey in China, the data on travel preferences and the perceived safety levels of automated vehicles can be collected. Then, a model is built to simulate the adoption of Level 4 automated vehicles and estimate the mode split for different scenarios. The results indicated that private AV modes are preferred, and business and nonwork trips may be the targeted market for all AV modes. Overall, value of automation increases with income for private modes, with large variance. Furthermore, Pro‐AV attitude has a positive effect on value of automation, especially for self‐owned AV and AV subscription. Accordingly, the needs‐based approach demonstrates a promising method to study the impact of new technologies on travel behaviors and provides insights for policy makers to promote more sustainable transportation systems. [ABSTRACT FROM AUTHOR]

• A novel self-supervised US reconstruction method based on deep neural network. • An encoder-decoder architecture produces high-quality US images. • Various regularizations are used to improve the reconstruction quality. • Thousand times faster than the other sparse regularization methods. • Coherent compounding is applied to further enhance the image quality. Image reconstruction from radio-frequency (RF) data is crucial for ultrafast plane wave ultrasound (PWUS) imaging. Compared with the traditional delay-and-sum (DAS) method based on relatively imprecise assumptions, sparse regularization (SR) method directly solves the inverse problem of image reconstruction and has presented significant improvement in the image quality when the frame rate remains high. However, the computational complexity of SR is too high for practical implementation, which is inherently associated with its iterative process. In this work, a deep neural network (DNN), which is trained with an incorporated loss function including sparse regularization terms, is proposed to reconstruct PWUS images from RF data with significantly reduced computational time. It is remarkable that, a self-supervised learning scheme, in which the RF data are utilized as both the inputs and the labels during the training process, is employed to overcome the lack of the "ideal" ultrasound images as the labels for DNN. In addition, it has been also verified that the trained network can be used on the RF data obtained with steered plane waves (PWs), and thus the image quality can be further improved with coherent compounding. Using simulation data, the proposed method has significantly shorter reconstruction time (∼10 ms) than the conventional SR method (∼1-5 mins), with comparable spatial resolution and 1.5-dB higher contrast-to-noise ratio (CNR). Besides, the proposed method with single PW can achieve higher CNR than DAS with 75 PWs in reconstruction of in-vivo images of human carotid arteries. [Display omitted] [ABSTRACT FROM AUTHOR]

The purpose of this research is to study the influence of aspect ratio and end conditions on the strength and failure mode of remolded soil samples in unconfined compressive strength tests. The digital image correlation method is used in this research to obtain the evolution process of the horizontal displacement field in remolded soil samples and analyze the deformation and failure characteristics in various sample sizes. Two-dimensional discrete element models of the soil samples are established to simulate the impact of different end-frictional conditions on stress-strain processes of samples. Results show that, with the growth of aspect ratios, the failure of samples transforms from tensile mode to shear mode, and the defects in the middle of samples become more obvious. Characteristic values of earthen sites' soil, such as peak strain, elastic modulus, and residual stress, change with various aspect ratios. The simulation results are in accordance with typical experiments, thus verifying the rationality of established discrete element models. By comparing the particle displacement directions and the respective proportions, the constraint caused by loading plate on samples is proved to be one of the reasons for the size effect. When the aspect ratio is higher than 1.0, the size effect disappears in end-frictionless samples. The research has practical significance to deepen understanding of the mechanism for unconfined compressive strength of site soil samples and provides scientific references for protection and reinforcement of earthen sites. [ABSTRACT FROM AUTHOR]

Obtaining lignin-based graphite-like microcrystallites at a relatively low carbonization temperature is still very challenging. In this work, we report a new method based on condensed structures, for regulating graphite-like microcrystalline structures via the incorporation of 4,4′-diphenylmethane diisocyanate (MDI) into the main structure of lignin. The effects of MDI on the thermal properties of lignin and the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers were extensively studied and investigated. The incorporation of MDI decreased the thermal stability of lignin, increased the carbon yield and enhanced the formation of graphite-like microcrystallites, which are beneficial for reducing energy consumption during the preparation of lignin-based carbon fibers. The modified lignin-based ultrafine carbon fibers (M-LCFs) demonstrated satisfactory electrochemical performance, including high specific capacitance, low charge transfer resistance, and good cycle performance. The M-LCFs-3/2 electrode had a specific capacitance of 241.3 F g−1 at a current density of 0.5 A g−1, and a residual ratio of 90.2 % after 2000 charge and discharge cycles. This study provides a new approach to control the graphite-like microcrystalline structure and electrochemical performance while also optimizing the temperature. • Lignin-based carbon fiber with graphite structure was prepared at a low temperature. • Condensed structure facilitate the formation of graphite-like structure. • MDI decreased the thermal stability of lignin and energy consumption of carbon fiber. • MDI-modified lignin shows fascinating application in supercapacitor. [ABSTRACT FROM AUTHOR]

Multitemporal interferometric synthetic aperture radar (MT-InSAR) technique is an important approach for surface deformation monitoring. Nonlocal adaptive multilooking approach has potential benefits for the filtering and coherence estimation in the data preprocessing steps of MT-InSAR technique. The kernel of nonlocal adaptive multilooking approach lies in the selection of statistically homogeneous pixels (SHPs). Various amplitude-based strategies, such as DespecKS and its variations, have been proposed for selecting SHPs. However, the detection rates of these methods are usually unsatisfactory in the case of small data sets. To overcome this limitation, SHPs are selected based on the adaptive joint data vector, which encompasses both time dimensional samples and spatial information. In this letter, the outliers of the time dimensional samples are removed first based on a revised boxplot method. Additionally, image segmentation and L1 norm are both introduced to adaptively construct joint data vector in the preset window. Experiments on five TSX images are used to verify the reliability and efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Some of the largest and best-preserved Buddhist art treasure houses in the world, namely the Mogao Grottoes, are located at the northwest edge of the region of the Qinghai-Tibet plateau and are adjacent to the Altun and Qilian mountains, where the geotectonic activity is intense and large earthquakes have occurred. Future earthquakes are one of the major threats to the caves of the Mogao Grottoes; therefore, it is important that their dynamic performance is studied when an earthquake occurs. To understand the dynamic performance of the densely distributed caves under the effect of earthquakes, as well as the long-term stability of the Mogao Grottoes, the stress distribution, deformation characteristics, and peak-acceleration amplification factor were analysed under rare-earthquake conditions using a finite-difference element. The numerical study revealed that the most dangerous state of the caves is the initial time when an earthquake occurs. The obvious tensile stress concentration appeared at the top and the bottom of the caves of the middle floor; the main damage was caused by the shear failure towards the direction of the free face and not by the tensile failure. A large permanent horizontal displacement of the caves occurred after an earthquake, mostly at the densely distributed caves of the middle floor. The acceleration amplification effect of the middle-floor caves was significant; the Fourier amplitudes of the acceleration (which were monitored in all caves) were significantly magnified at the frequencies of 3 ~ 4 Hz and 7 ~ 9 Hz, whereas the Fourier amplitudes of the acceleration which were monitored in the middle-floor caves were almost amplified within the entire frequency range. Although the maximum stress was within the allowed limit and no tensile failure occurred, great permanent inhomogeneous horizontal displacements and large accelerations could have a negative effect on the stability of caves and the preservation of wall paintings. Moreover, it was assumed that the calculation results could serve as a type of guidance and as advice on the preventive protection of the Mogao Grottoes. [ABSTRACT FROM AUTHOR]

Calcined ginger nut (CGN) has been applied in grouting mortars for anchoring unstable earthen sites, but the lack of scientific research limits its application. In this study, CGN-based grouts admixed with fly ash (F), quartz sand (S), or both are evaluated. To explore the optimal mixture ratios, three types of mixing groups (five proportion gradients in each group) are established. All the grout specimens are buried and maintained outdoors, and their physical (shrinkage rate, density, elastic wave velocity, and permeability) and mechanical properties are continuously examined over 180 days. The solidification processes at different ages are simultaneously observed by means of scanning electron microscopy (SEM) images. The results indicate that the physical properties of grouts are influenced significantly by initial moisture content but then remain steady for approximately 15 days. Quartz sand can effectively reduce the shrinkage rate of grouts as well as adjust their density and permeability, and might be considered as an ideal mixing material for CGN. In the solidification process, grouts are rapidly solidified after the initial hydration reaction, and the carbonation reaction in the later stage constantly improves their mechanical strength, with physical properties kept relatively stable. SEM images show fly ash and quartz sand particles are cemented by CaCO 3 crystals. Through comprehensive comparison, the grouts with the mass ratio of CGN and S at 1:1 are found to better satisfy requirements that grouts should be compatible with earthen sites. [ABSTRACT FROM AUTHOR]

Water-salt migration is an important reason for the development of basal erosion which seriously threatens the conservation of earthen sites. Studies in cutting-off or redirection of the water-salt migration path become vital. Polyvinyl alcohol (PVA) composite soil with extreme hydrophobicity shows the potential as the cushion layer with the damp-proof function, but the feasibility of preventing basal erosion based on the PVA cushion layer still lacks verification. In this study, for the embedded and non-embedded PVA cushion layers, water-salt distribution and morphology of earthen wall after repeated injection of salt solution were compared. The results showed that PVA cushion layer changed the water-salt migration path and promoted the accumulation of soluble salt on the ground outside the wall rather than the bottom of cushion layer, which effectively prevented basal erosion. A numerical model based on HYDRUS-2D confirmed that a partial laying of hydrophobic cushion layer under the wall cannot effectively prevent the water-salt migration, and a full laying of cushion layer should be adopted to prevent basal erosion. The cushion layer was recommended to extend towards the direction of the earthen wall instead of towards the sides, which also resisted the destructive effects of sand-driving wind and runoff erosion. • Basal erosion caused by water-salt migration is directly confirmed. • Water-salt distribution for models with/without PVA cushion layer is explored. • PVA cushion layer can inhibit basal erosion. • Reasonable laying modes of the hydrophobic cushion layer is presented. [ABSTRACT FROM AUTHOR]

Erectile dysfunction (ED) caused by cavernous nerve injury (CNI) is refractory to heal mainly ascribed to the adverse remodeling of the penis induced by ineffectual microvascular perfusion, fibrosis, and neurotrophins scarcity in cavernosum. Phosphodiesterase type V inhibitors (PDE5i) have been regarded as an alternative candidate drug for avoiding penile neuropathy. However, the therapeutic efficacy is severely limited due to poor accumulation under systemic medication and endogenous nitric oxide (NO) deficiency in cavernosum. Herein, an innovative liposomal microbubble (MB) loaded with both Sildenafil (one of PDE5i) and NO was designed. Ultrasound‐targeted MB destruction (UTMD)‐mediated efficient release and integration erectogenic agents into corpus cavernosum with high biosafety. On a bilateral CNI rat model, the multifunctional MB‐cooperated UTMD improved microvascular perfusion in penis, simultaneously, alleviated hypoxia and oxidative stress, indicating successful activation of NO–cyclic guanosine monophosphate pathway. Also, evaluation of the endothelial/muscular composition, intracavernosal pressure, and neural integrity in the penis proved that coordinated intervention reversed the abnormal structural remodeling and promoted the recovery of functional erection. Our work demonstrates that MB loading Sildenafil and NO combined with UTMD hold great promise to "awaken" the efficacy of PDE5i in neurogenic ED, which provided a superior option for ensuring penile rehabilitation. [ABSTRACT FROM AUTHOR]

Highlights • A technique to improve the consolidation effect used on earthen sites. • The RGB color space was applied to evaluate the colour changes of the treated samples. • The concept of composite reinforcement was proposed. • The sequence of consolidation of organic and inorganic materials was critical in the composite materials. Abstract Conservation practices employed thus far have proven that single materials cannot suitably protect earthen sites. This study compares the effectiveness of single and composite materials, to explore whether composite materials are potential candidates for use in conservation. Soils from the Great Wall of Yongchang, Gansu Province, China, were treated with five types of materials, namely, inorganic materials, organic products, composite materials composed of organic and inorganic materials in different orders, and ethanol. Changes in the colour, weight, mechanical properties, water resistance, microstructures, and element composition were evaluated after treatment. Better reinforcing effects were obtained by applying an organic material and then using an inorganic material. Results showed that a composite material with reasonable reinforcing sequence can greatly improve the properties of soils; hence, composite materials are promising for use in the protection of cultural relics in the future. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) fueled by hydrogen-rich gas are promising systems to substitute fossil fuel resources. This review evaluates state of the art and perspectives for the catalysts such as supported Ni, noble metals, and base metal oxide catalysts used for catalytical CO purification (SMET, PROX) in H 2 -rich reformates for PEMFCs applications. The factors affecting activity like support effect, metal size effect, promoters, and metal-support interaction are assessed and thoroughly discussed. It is remarked that the challenges for their practical applications are to (i) achieve acceptable CO outlet concentration in ppm level with wide temperature window (ii) minimize undesired loss of H 2 and inhibit the occurrence of side reactions (iii) develop high performance catalysts with high resistance to CO 2 and steam under realistic conditions. Developing novel catalysts for catalytical CO purification based on the structure-activity relationship will resolve the challenges required for their practical applications. [Display omitted] • H 2 -fueled PEMFCs are promising to solve environmental pollution and energy shortage. • Selective CO methanation and oxidation are critical reactions for hydrogen purification. • Recent work to develop catalysts for CO clean-up in H 2 -rich reformate are reviewed. • The structure-activity relationship of the catalysts is comprehensively discussed. • State of the art and perspectives for CO clean-up catalysts are presented. [ABSTRACT FROM AUTHOR]

The Mogao Grottoes are among the most famous sites on the World Heritage list. Several large-scale preservation projects were implemented in 1962, 1982, and 2008, respectively, to improve their preservation conditions. According to field investigation and assessment in recent years, the cliff is stable on the whole because of the reinforcement projects. Among them, there are still 42 potentially dangerous bodies, which may not be stable in some conditions. For the purpose of building the monitoring and early warning system and the long-term preventive preservation of the Mogao Grottoes, an innovative analytical method based on the Analytic Hierarchy Process (AHP) and Fuzzy-AHP was applied to assess the hazard of potentially dangerous bodies within the cliff. Firstly, the hazard was classified into six groups: very high, high, moderate, low, very low, and no hazard, in this study. Secondly, the AHP method was applied to calculate the impact index of each causative factor, and then the hazard assessment of dangerous bodies was made based on statistical analysis. Finally, the Fuzzy-AHP method was applied to calculate the correlation of each factor and determine the comprehensive hazard class. The results indicate that Fuzzy-AHP seems to be more accurate than AHP in hazard assessment. Meanwhile, there is a very high risk body that can threaten 10 caves, three high risk bodies that can threaten 13 caves, and 15 moderate risk bodies can threaten 69 caves in total, while the remaining bodies are defined as low or very low grades. Overall, the results of this study provide much data and a theoretical model in the construction of a monitoring and early warning system currently. Furthermore, the new numerical simulation method also holds the potential application to assess the hazards of other types of heritage sites. [ABSTRACT FROM AUTHOR]

To further improve the tensile and self-healing properties of engineered cementitious composites (ECCs) for their special uses such as harsh environments, plastic hinge regions, and old members strengthening, an innovative high-performance superelastic Ni-Ti shape memory alloy (SMA) cable grid-reinforced ECC (SMACG-ECC) was first proposed and tested in this study. The effects of water-binder ratio, cable grid material, and reinforcement ratio on the cyclic tensile properties and crack closure performance of the proposed SMACG-ECC were systematically examined. Test results revealed that the tensile strength, initial crack strength, ultimate tensile strain, dense crack, crack closure, and self-healing properties of the traditional ECC were obviously improved by being reinforced with the SMACG. Compared with the ordinary steel cable grid-reinforced ECC (SCG-ECC), the proposed SMACG-ECC exhibited approximately 50 % lower first crack strength, similar tensile strength and deformation ductility, but a 53.7 %-75.1 % greater energy dissipation, 75.8 %-80.2 % lower residual strain, and 80.4 %-83.4 % smaller maximum residual crack width. The tensile properties, cracking performance, and self-healing ability improved with the incorporation of SMACG as well as the increase in reinforcement ratio. Notably, most specimens showed satisfactory composite operation with no cable ends slipping during the entire cyclic loading process, with a maximum tensile strain amplitude of 8 %. ● Novel multifunctional SMA cable grid-reinforced ECC (SMACG-ECC) was first proposed and tested. ● Cyclic tensile response and crack closure performance of the SMACG-ECC were examined. ● Effects of water-binder ratio, cable grid material, and reinforcement ratio on the SMACG-ECC were investigated. [ABSTRACT FROM AUTHOR]

Epimesatines A–I, nine undescribed prenylated flavonoids, along with ten known analogues, were isolated from the aerial parts of Epimedium sagittatum Maxim. The structures and absolute configurations of epimesatines A–I were determined using a combination of spectroscopic data, Rh 2 (OCOCF 3) 4 -induced electronic circular dichroism (ECD) experiments, ECD comparisons, and X-ray crystallography analysis. Epimesatines A and I displayed notable activities on the viabilities of human non-small cell lung cancer (NSCLC) A549 cells with IC 50 values of 1.77 and 9.97 μM, respectively. Furthermore, epimesatines A and I significantly inhibited the expression of sphingosine kinase 1 (SPHK1) in A549 cells. In addition, none of these compounds showed obvious toxicity on normal human lung bronchial epithelial BEAS-2B cells. Nine undescribed prenylated flavonoids, named epimesatines A–I, were isolated from Epimedium sagittatum Maxim. Epimesatines A and I showed significant activities against SPHK1 in A549 cells. [Display omitted] • Nineteen prenylated flavonoids including nine undescribed ones were isolated. • Their absolute configurations were determined by Rh 2 (OCOCF 3) 4 -induced ECD experiments and X-ray crystallography analysis. • The complete NMR data of 5,7-dihydroxy-4′-methoxy-8-prenylflavonoid and honyucitrin were reported herein for the first time. • Epimesatines A and I s ignificantly inhibited the expression of SPHK1 in A549 cells. [ABSTRACT FROM AUTHOR]

The outer steel tube in a concrete-filled steel tubular (CFST) column confines the core concrete and improves the compressive strength of the core concrete. When there is a notch damage in the tube, the confinement effect may be affected. The confinement effects of the notched steel tube in rectangular CFST columns were systematically investigated by using numerical approaches. Refined three-dimensional finite element models with advanced concrete constitutive relations were established. With the verified finite element modeling method, full-sized square CFST columns with horizontal, vertical, or diagonal notches at different locations of the steel tube were simulated. Stress distributions and deformation modes of the steel tube and core concrete were analyzed. Columns with a horizontal notch at the plate center location displayed a higher axial strength reduction than those with vertical notches. A parametric study was performed to investigate the influences of concrete strengths, steel strengths, steel ratios, notch length to column width ratios, and notch angles on the compressive strengths of the rectangular CFST columns. A practical design formula was proposed based on the obtained results. The proposed formula could effectively predict the influences of different notches on the confinement effect in the notched CFST columns. [ABSTRACT FROM AUTHOR]

Wheel-rail force is an essential indicator for evaluating rail vehicles' operational safety. This study combined the traditional time domain identification method for dynamic loads and the machine learning method to rapidly identify the wheel-rail forces for rail vehicles and evaluate the operational safety of rail vehicles. Firstly, a vertical dynamic model of rail vehicles considering the nonlinearity of partial suspension parameters was established. The acceleration responses of the axle box and frame under random excitation of the track were calculated by the Runge–Kutta method, with the random noise simulating the actual observation noise as the input for the wheel-rail force identification model. Secondly, in response to the difficulty of identifying lateral wheel-rail forces for rail vehicles, a nonlinear autoregressive with exogenous inputs (NARX) model was introduced to construct relationships between vehicle component responses and lateral wheel-rail forces. Then, the influences of input responses and model parameters on the identification results of lateral wheel-rail forces were analyzed, and the lateral wheel-rail forces under straight and curved negotiation were trained and identified. Finally, a comprehensive identification method of wheel-rail forces for rail vehicles based on time domain and machine learning methods was proposed, which can identify the vertical and lateral wheel-rail forces of each wheelset's left and right wheels. The operational safety indicators, derailment coefficient and wheel unloading rate were verified with a simulation model. The Pearson correlation coefficients were not less than 0.96 and 0.95 under straight-line conditions and not less than 0.76 and 0.85 under curved conditions. [ABSTRACT FROM AUTHOR]

Five new compounds were identified from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, involving UV, IR, NMR spectrum and HRESIMS analyses. The absolute configuration of compound 2 was proved by comparing their experimental and calculated ECD spectrum. The vitro bioactive assay of all compounds suggested that compound 1 , 3 , 4 , 5 and 6 may have potential anti-asthmatic activities. five undescribed compounds were isolated from the stems of E. equisetina and assessed for its antiasthma activities. [Display omitted] • Five compounds were isolated from the stems of E. equisetina. • Their structures were elucidated by NMR and mass spectrometry. • The absolute configurations were deduced by interpretation of ECD. • The antiasthma activities of all the isolated compounds were evaluated. [ABSTRACT FROM AUTHOR]

Historical relics of Jurassic sandstones in southwest China have been subjected to weathering damage. Exfoliation, characterized by the detachment of multiple thin stone layers sub-parallel to the stone surface, is common in sandstone heritage sites. However, its mechanism of action remains poorly understood. In this study, a conceptual model of exfoliation is drawn from the literature and field investigations. To quantitatively determine the exfoliation mechanism, a range of non-destructive field-based methods (surface hardness, water absorption test, roughness, and amplitude of residual spalling layers) and laboratory analyses (scanning electron microscopy (SEM) and X-ray diffraction (XRD)) are adopted as weathering agents for separated detachments. In addition, the grain and pore sizes of weathering products are analyzed using digital image techniques. The results show that the roughness, water absorption coefficient, and pore size in sandstone surfaces increase from the inner layer to the outer layer, and their hardness and grain size decrease, respectively. The proportions of quartz, dolomite, and illite increases from the interior to the exterior, whereas the proportion of feldspar decreases correspondingly. The residual column strip structure derived from feldspar alteration and a mixed montmorillonite-illite mineral layer can be observed in the SEM images. It can be inferred from surviving environmental analysis that comprehensive actions from solar radiation, acid rain attack and capillary rise lead to sandstone exfoliation. In addition, the alteration of feldspar plays an important role during sandstone exfoliation. The results of this study enhance our understanding of the exfoliation of the Jurassic sandstone of the Chongqing Danzishi rock carvings in China. • Exfoliation was comprehensive studied and its mechanism was quantitatively revealed. • Roughness, water absorption coefficient and pore size increase from the inner layer to the outer layer, and hardness, grain size and propotion of feldspar decrease correspondingly. • Comprehensive actions from solar radiation, acid rain attack and capillary rise lead to sandstone exfoliation. [ABSTRACT FROM AUTHOR]

Purpose: This research aims to investigate the intervention and mechanism of 50% acetone extract of C. officinalis leaves (SZYY) on melanoma xenografts. Patients and Methods: Tumor size and cardiac function were measured via ultrasound. The accumulation of 2-deoxy-D-glucose (2-DG) in tumor tissue was examined with near-infrared in vivo imaging. Flow cytometry was performed to assess apoptosis and reactive oxygen species (ROS) levels in tumor and immune cells in spleen. The levels of inflammatory cytokines in serum were detected by cytometric bead array. The expression of proliferation-, apoptosis-, and angiogenesis-related proteins in tumor cells was measured to evaluate the underlying mechanisms. Subsequently, the effects of four compounds separated from SZYY on the proliferation and migration of A375 cells and STAT3 signaling were examined. The peak identification and contents of the four components were performed via high-performance liquid chromatography (HPLC). Finally, we evaluated the inhibitory effects of STAT3 overexpression on the cytotoxic activity of four constituents in A375 cells. Results: SZYY inhibited the growth and glycolysis of melanoma xenograft in mice, improved cardiac function, increased the percentages of macrophages, neutrophils, and lymphocytes in spleen, reduced the levels of IL-6, IL-17A, TNF-α, and IFN-γ in serum, promoted apoptosis and oxidative stress in tumor tissues, and inhibited STAT3 phosphorylation and expression of angiogenic factors. Chemical analysis showed that SZYY is rich in loganin, rutin, triohimas C, and triohimas D, which all could restrain the proliferation and migration of A375 cells and inhibit the phosphorylation and nuclear translocation of STAT3. Moreover, STAT3 overexpression could diminish the cytotoxic activity of four compounds on A375 cells. Conclusion: SZYY could exert anti-melanoma effects via inhibiting STAT3 signaling to induce apoptosis and inhibit tumor angiogenesis. Its active ingredients might be loganin, rutin, triohimas C, and triohimas D. [ABSTRACT FROM AUTHOR]

Engineering structures and materials will undergo fatigue, aging, and other degradation behaviors during long-term service under the combined influence of complex boundary conditions. These service damages make the materials and structures no longer meet the initial design requirements and pose a potential risk to the service system. This study proposes a material mesoscopic model to decouple the microstructure into a system composed of matrix and void phases. The matrix phase has an invariant constitutive relationship as an ideally undamaged material, and the different evolutionary behaviors of the void phase are described as damage evolution functions and lead to different stress–strain behaviors of the actual material. First, the damage described by different definitions is proposed, and a nonlinear function of damage evolution consistent with the Weibull distribution characteristic of microstructural continuity is derived. Then, an experimental–numerical method is improved to accurately identify the accelerated damage evolution behavior under various strain rates. Finally, the ideally undamaged constitutive of the matrix phase and the damage evolution function of the void phase are established, which can cover the void nucleation, growth, and aggregation process. Besides, the damage sequence interaction model is established in conjunction with the mesoscopic physical mechanism, and the total damage evolution function for materials containing prior service damage in subsequent ductile deformation is achieved by measuring the apparent elastic modulus of the material only. Finally, the ideally undamaged constitutive and damage evolution function are calibrated for aluminum alloy 6005A-T6, commonly used in the car body structure of rail vehicles, and verified with damaged specimens that experienced certain service loads. The material's damage sequence interaction mode is determined, and the rate-dependent residual strength is predicted. • Material is decoupled into the matrix and void phases to describe undamaged constitutive and damage evolution separately. • The proposed experimental–numerical method decouples the stress weakening due to geometric necking and damage evolution. • The established damage sequence interaction model can predict the residual strength of materials with prior damage. • Only nondestructive testing is required to obtain the actual constitutive relationship of the service structure and material. [ABSTRACT FROM AUTHOR]

• Hydrophobicity arising from PVA changes erosion in different parts of earthen site. • Drying temperature control is a feasible method to eliminate the hydrophobicity. • Soil wettability is a crucial evaluation criterion for protection of earthen sites. • Drying temperature, surface roughness, PVA and water contents affect the wettability. Earthen sites in northwest China represent a precious cultural heritage; however, these sites have been seriously damaged by weathering. Chemical consolidation treatment is a widely accepted conservation method, and PVA solution with a high degree of alcoholysis has exhibited potential for improving the strength of soil. However, research on the influence of the PVA solution on the wettability of these earthen sites is rarely reported. Therefore, the aim of this study is to investigate the change in wettability of earthen sites protected with the PVA by laboratory experiments. First, the compressive strength and wettability of soil specimens are analysed with varying PVA content, water content, and drying temperature. The results indicate that the soil strength and hydrophobicity are highest when the PVA content in the soil is 1.0 wt%. The relationship between the soil hydrophobicity and water content follows a one-peak distribution, whereas the hydrophobicity decreases with increasing in drying temperature and is lost when the drying temperature is 80 °C or more. Second, factors influencing the wettability of the composite soil are discussed, and water vapour permeability of 1 cm thick composite soil is investigated in conjunction with exfoliation of surface crust. Finally, the feasibility of protecting different parts (i.e. the upper, middle, and lower parts) of earthen sites with PVA is briefly discussed, and it is emphasised that the wettability should be considered as crucial evaluation criterion for the protection of earthen sites. [ABSTRACT FROM AUTHOR]