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Using pyrrhotite containing aggregates in concrete foundations can lead to premature deterioration visibly identifiable by extensive map cracking, expansion and deformation of the concrete foundation. The two main expansion mechanisms are: (1) aggregate expansion induced directly by the oxidation of pyrrhotite inclusions and (2) matrix expansion due to the consequent internal sulfate attack (ISA). The relative contribution of these two mechanisms of expansion were investigated in this study. Theoretical calculations based on the practical combinations of oxidation products and degrees of oxidation indicated that aggregate expansion alone may not be sufficient to cause severe deterioration of the concrete incorporating pyrrhotite-bearing aggregate. Observations and this investigation show that this mechanism leads to microcracking which initiates the deterioration process. The combination of microcracking and the release of sulfate facilitates and intensifies the local ISA. The strain derived from the ISA is substantially higher than the typical ultimate tensile strain of a typical matrix used on foundation walls, thus adding additional mechanical stress on the material, and allowing the development of the typical map cracking throughout the concrete.

Himawari-8 satellite, equipped with an advanced Himawari imager (AHI), has been widely employed for cloud detection tasks due to its high-spatiotemporal resolution. In this article, we propose a deep learning model named dual-branch deformable convolutional network (DBDCN) to detect convective cloud from AHI data. Specifically, we first choose some infrared channels from AHI to compute their difference. These brightness temperature difference (BTD) data are sensitive to cloud detection, thus providing complementary information for AHI. Then, both AHI and BTD are used as inputs of DBDCN, which adopts a dual-branch structure to effectively combine them together. Considering that convective clouds often exist in variable shapes, we use deformable convolutions to extract convective clouds' features in each branch. In addition, in order to fuse the complementary features from both branches, we propose a crossbranch fusion block. To evaluate the performance of our proposed DBDCN, we collect a convective cloud dataset, covering most of regions in southern China (i.e., 97$^\circ$E to 122$^\circ$E, 20$^\circ$N to 35$^\circ$N). Experimental results show that DBDCN is able to achieve better detection performance than the widely used threshold methods and existing convolutional neural networks in most cases.

There has been a growing interest in utilizing 3D printing technology for military and civil defense engineering, especially in enhancing the resilience of infrastructure against impacts. Due to its distinctive additive manufacturing process, 3D printed concrete (3DPC) shows anisotropic behavior when subjected to static loads. However, research on its performance under dynamic conditions remains limited. Therefore, this study explores the characteristics of 3DPC under static and dynamic loads. Quasi-static results showed that incorporating textile significantly enhanced the deformation capacity of specimens, with the ultimate deflection and flexural toughness of basalt textile reinforced specimens in the X direction reaching 1.07 mm and 4206.9 N·mm, which are 118 % and 117 % higher than control specimens without textiles, respectively. The mechanical properties of 3DPC specimens showed increasing trend from static to impact loads. The impact results indicated that the peak load increased with the increase in impact energy. Adding two types of textiles showed different anisotropic mechanical properties which are associated with the patterns of cracking and failure. The addition of basalt textiles primarily enhanced the energy dissipation properties of 3DPC, with increases up to 98.2 %. The AR-glass textile was superior in terms of maintaining peak force under multiple impacts.

Abstract Background Osteoarthritis (OA), a degenerative disease with a high global prevalence, is characterized by the degradation of the extracellular matrix (ECM) and the apoptosis of chondrocytes. Ajugol, a extract derived from the herb Rehmannia glutinosa, has not yet been investigated for its potential in modulating the development of OA. Methods We employed techniques such as western blotting, immunofluorescence, immunohistochemistry, X-ray imaging, HE staining, and SO staining to provide biological evidence supporting the role of Ajugol as a potential therapeutic agent for modulating OA. Furthermore, in an in vivo experiment, intra-peritoneal injection of 50 mg/kg Ajugol effectively mitigated the progression of OA following destabilization of the medial meniscus (DMM) surgery. Results Our findings revealed that treatment with 50 μM Ajugol activated TFEB-mediated autophagy, alleviating ER stress-induced chondrocyte apoptosis and ECM degradation caused by TBHP. Furthermore, in an in vivo experiment, intra-peritoneal injection of 50 mg/kg Ajugol effectively mitigated the progression of OA following destabilization of the medial meniscus (DMM) surgery. Conclusion These results provide compelling biological evidence supporting the role of Ajugol as a potential therapeutic agent for modulating OA by activating autophagy and attenuating ER stress-induced cell death and ECM degradation. The promising in vivo results further suggest the potential of Ajugol as a treatment strategy for OA progression.

The transformation of free state organic micro-pollutants (MPs) has been widely studied; however, few studies have focused on mixed and bound states MPs, even though numerous ionizable organic MPs process a strong tendency to combine with dissolved organic matters in aquatic environments. This study systemically investigated the distribution and toxicity assessment of tetracycline (TET) transformation products in free, mixed and bound states during UV, UV/H2O2, UV/PS and CNTs/PS processes. A total of 33 major transformation products were identified by UPLC-Q-TOF-MSMS analysis, combining the double bond equivalence and aromaticity index calculations. The binding interaction would weaken the attack on the dimethylamino (-N(CH3)2) group and induce the direct destruction of rings A and B of TET through the analysis of 2D Kernel Density changes and density functional theory (DFT) calculations. Toxicity assessment and statistics revealed that the intermediate products with medium molecular weight (230≤ m/z ≤ 380) exhibited higher toxicity, which was closely related to the number of the rings in molecular structures (followed as 2»3 > 1≈4). A predicted toxicity accumulation model (PTAM) was established to evaluate the overall toxicity changes during various oxidation processes. This finding provides new insight into the fate of bound MPs during various oxidation processes in the natural water matrix.

The binding performance of dissolved organic matters (DOM) plays a critical role in the migration, diffusion and removal of various residual pollutants in the natural water environment. In the current study, four typical DOMs (including bovine serum proteins BSA (proteins), sodium alginate SAA (polysaccharides), humic acid HA and fulvic acid FA (humus)) are selected to investigate the binding roles in zwitterionic tetracycline (TET) antibiotic under various ionic strength (IS = 0.001–0.1 M) and pH (5.0–9.0). The dialysis equilibration technique was employed to determine the binding concentrations of TET, and the influence of IS and pH on binding performance was evaluated via UV–vis spectroscopy, total organic carbon (TOC), and Excitation-Emission-Matrix spectra (EEM), zeta potentials and molecule size distribution analysis. Our results suggested that carboxyl and phenolic hydroxyl were identified as the main contributors to TET binding based on the fourier transform infrared spectroscopy (FTIR) analysis, and the binding capability of four DOMs followed as HA > FA » BSA > SAA. The biggest binding concentrations of TET by 10 mg C/L HA, FA, BSA and SAA were 0.863 μM, 0.487 μM, 0.084 μM and 0.086 μM, respectively. The higher binding capability of HA and FA is mainly attributed to their richer functional groups, lower zeta potential (HA/FA = −15.92/-13.54 mV) and the bigger molecular size (HA/FA = 24668/27750 nm). IS significantly inhibits the binding interaction by compressing the molecular structure and the surface electric double layer, while pH had a weak effect. By combining the Donnan model and the multiple linear regression analysis, a modified Karickhoff model was established to effectively predict the binding performance of DOM under different IS (0.001–0.1 M) and pH (5.0–9.0) conditions, and the R2 of linear fitting between experiment-measured logKDOC and model-calculated logKOC were 0.94 for HA and 0.91 for FA. This finding provides a theoretical basis for characterizing and predicting the binding performance of various DOMs to residual micropollutants in the natural water environment.

In a wheat/maize rotation system, nitrogen (N) accounts for a large proportion of basal fertilizer, but soil N loss and the resulting environmental risk simultaneously exist worldwide. This study applied different urease/nitrification inhibitors together with basal fertilizers and investigated their effects on soil N level and grain yield. Six N stabilizing combinations consisted of two urease inhibitors (HQ and NBPT) and three nitrification inhibitors (DCD, DMPP, and Nitrapyrin). The treatments supplied with urease/nitrification inhibitors reduced, to some degree, the conversion rate of NH4+ into NO3−, and kept NH4+ content higher in surface soils for a longer time. Compared to CK, A1 treatment supplied with 1.5% HQ + 4% DCD well-maintained the levels of soil alkali-hydrolyzable N and NH4+. For example, alkali-hydrolyzable N and NH4+ contents at 0–20 cm soil layer under A1 were increased by 8.59–41.6% and 8.15–14.5% more than CK, respectively. Based on the entire growth period of wheat and maize rotation, urease/nitrification inhibitors improved soil available N in surface soils but did not prevent NH4+ and NO3− leaching, especially in the intensive rainfall season. The combinations of HQ and DCD or Nitrapyrin significantly enhanced crop yield. Specifically, crop yields under A1 and A3 (1.5% HQ + 0.25% Nitrapyrin) were 16.3% and 14.3% higher than CK, respectively. The N stabilizing combinations also promoted N intake and transport at every growth stage. The maximum N accumulation was increased by 27% under A1, when compared to CK. The treatments supplied with urease/nitrification inhibitors also achieved higher apparent N recovery efficiency, N agronomic efficiency, and N partial factor productivity. Consequently, the combinations of urease/nitrification inhibitors could improve N availability at 0–40 cm soil layer, which in turn improved N use efficiency of wheat and maize. The results suggested that the two urease/nitrification inhibitor combinations, 1.5% HQ + 4% DCD (A1) and 1.5% HQ + 0.25% Nitrapyrin (A3), were optimal N stabilizing agents and worthy of further study.

A deep buried pipe energy pile (DBP-EP) is a composite structure that integrates ground-source heat pump (GSHP) systems and inside buried pipe energy piles (IBP-EP) to effectively achieve the improvement of heat transfer efficiency and quantity. Utilizing this technology in building a pile foundation can contribute to reducing carbon emissions. This paper studies the variation rules of the thermomechanical response of DBP-EP under temperature load via field testing and numerical simulation. The results show that, under heating and cooling conditions, the DBP-EP temperature variation within the pile is substantial, while there is no significant change in the temperature field at the bottom of the pile. This is different from the internal temperature change of the temperature distribution of IBP-EP. The minimum axial average strain of the DBP-EP under the cooling condition is significantly smaller than that under the heating condition. However, the additional axial average strain under the temperature load is significantly larger than that in the heating condition, resulting in larger additional axial stress when the pile is cooled. The connection between the pile and foundation must considered in design due to the large settlement of the pile top under cooling conditions. When only under the temperature load, the maximum axial average pressure increments of the pile in our test during heating and cooling are −85.3 kN/°C and 99.4 kN/°C, respectively, suggesting that the additional load cannot be ignored.

Background: One of the major concerns of cancer therapy is the emergence of multidrug resistance (MDR). The MDR-associated ATP-binding cassette sub-family B member 1 (ABCB1) transporter is established to mediate resistance against numerous anticancer drugs. In this study, we demonstrated that the Ubiquitin-like modifier activating enzyme 1 (UBA1) inhibitor TAK-243 is transported by the ABCB1. Methods: MTT assay was performed to evaluate the cytotoxicity of TAK-243. Western blot was carried out to investigate if TAK-243 affect to ABCB1 protein expression in cancer cells. High Performance Liquid Chromatography (HPLC) and ATPase assay were carried out to confirm TAK-243 as an ABCB1 substrate. [3H]-paclitaxel accumulation assay was used to determine the MDR reversal effect of TAK-243. Computational docking analysis was performed to investigate the drug-transporter binding position. Results: The cytotoxicity profile showed that TAK-243 was less effective in ABCB1-overexpressing cells than in the parental cells, but pharmacological inhibition or knockout the gene of ABCB1 was able to reverse TAK-243 resistance. Furthermore, TAK-243 potently stimulated ABCB1 ATPase activity and the HPLC analysis revealed that TAK-243 accumulation was significantly reduced in ABCB1-overexpressing cells. Finally, the computational docking analysis indicates a high binding affinity between TAK-243 and human ABCB1 transporter. Conclusions: Our in vitro data characterized TAK-243 as a substrate of ABCB1, which may predict limited anticancer effect of this compound in drug resistant tumors.

A deeply buried pipe energy pile (DBP-EP) combines the advantages of a ground source heat pump (GSHP) and an inside buried pipe energy pile (IBP-EP) and is an efficient, clean, and energy-saving technology. Based on field tests and numerical simulations, this paper explores the temperature distribution and heat exchange effects of DBP-EP under different influencing factors. The results show that when the pile-to-well ratio is approximately 0.3–0.4, the heat exchange of the energy pile obtains the best benefit; the inlet water temperature is the most significant factor affecting the heat exchange effect of the energy pile, and when combined with a reasonable pile-to-well ratio, the energy pile obtains the best heat exchange effect; the flow rate has a significant impact on the heat exchange effect of the energy pile, but needs to be set reasonably according to the pile-to-well ratio; the influence of inlet water temperature, well depth, flow rate, and pile length on the heat exchange efficiency of the energy pile is gradually weakened. The research results of this paper provide a theoretical basis for the structural design optimization of DBP-EP and promote the popularization and application of energy pile technology.

This paper presents an experimental study on the flexural behavior of an innovative CA-UHPC (ultrahigh-performance concrete containing coarse aggregate) slab with high and low reinforcement ratios. A total of eighteen CA-UHPC slabs were tested to failure under the parameters of longitudinal reinforcement ratio, curing method, and maximum aggregate size. Test results indicated that sufficient longitudinal reinforcement should be embedded to prevent the brittle failure and disastrous damage. High ductile failure mode was observed for specimens with high reinforcement ratio compared with specimens with low reinforcement ratio. Instead of extensively crushing as normal strength concrete, delamination failure appeared in the compression zone of the CA-UHPC slabs owing to the fibers’ bridging effect, the yielding of longitudinal reinforcement, and the large expansion of flexural cracks which led to the final failure. The reinforced CA-UHPC slabs demonstrated excellent deformability, and ultimate ratio of deflection to span increased from 1/281 to 1/12 when the reinforcement ratio raised from 0% to 3.45%. Stiffness of the reinforced specimens at the flexural cracking state was about 88% and only approximately 6% at the ultimate state, but nearly 50% of the initial stiffness remained when the longitudinal reinforcements yielded, which indicated superior load resistance ability and excellent postcracking deformability. A new ductility index was proposed to evaluate the postcracking ductility of the CA-UHPC specimens. Finally, test results were compared with the flexural strength predictions of CECS 38-2004, ACI 544.4R, and BS EN 1992.

The seismic performance of ultra-high-performance concrete–high-strength steel pier was studied using fiber elements, which are capable to model accurately elastic–plastic behavior of members with fibers of different material constitutive relations. For high-strength steel–ultra-high-performance concrete piers, the modified Kent–Park model was utilized to describe the compressive stress–strain relations of ultra-high-performance concrete and high-strength steel-confined ultra-high-performance concrete, respectively, by determining four key parameters. A finite element model was established to simulate the hysteretic response; conduct parameter analysis including axial load ratio, longitudinal reinforcement ratio, and transverse reinforcement ratio; and assess the maximum ground acceleration capacity based on inelastic response spectra for high-strength steel–ultra-high-performance concrete piers. The conclusions are summarized that modified Kent–Park model is proved to be effective due to experimental data. The calculated hysteretic curves of high-strength steel–ultra-high-performance concrete piers show good agreement with the experimental results. Three parameters have evident effects on seismic performance of high-strength steel–ultra-high-performance concrete piers, which indicates that various seismic demands can be achieved by reasonable parameter settings. Compared to nonlinear dynamic analysis based on finite element model, the results provided by inelastic response spectra are less conservative for short high-strength steel–ultra-high-performance concrete piers under high axial load ratio.

The design of fiber-reinforced polymer–concrete hybrid beam is usually governed by deformation. Due to the rigidity degradation caused by fiber-reinforced polymer–concrete slip, the load–slip and load–deflection curves demonstrate a bilinear characteristic. The originality of this article is to propose a bilinear analytical model and to determine two dominant parameters in this model, namely, initial bond stress and slip modulus of the interconnection. This model consists of two distinct linear stages. In Stage I, full composite action between fiber-reinforced polymer and concrete is obtained, and no slip exists; Stage II commences once interfacial bond force diminishes, when slip increases linearly versus load, and the overall beam rigidity drops compared with that in Stage I, indicating only partial composite action is realized. Finally, three large-scale specimens were tested to validate the proposed bilinear model and to calculate the two parameters.