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Abstract Considerable carbon emissions from the cement industry pose a notable challenge to achieving long-term sustainable development and creating an enriched social environment. Biochar (BC) obtained from biomass pyrolysis can be used as a carbon-negative material, and it plays a crucial role in the reduction of global carbon emissions. The development of more efficient and cost-effective technologies to fully realize this potential and reduce the environmental impact of BC production and use remains a formidable challenge. The utilization of BC to prepare sustainable cementitious composites with economically value-added benefits has recently attracted much research interest. Therefore, this review analyzes factors influencing the physicochemical properties of BC and their optimization methods, as well as the impact of BC addition on various cement composites and their potential applications. Besides, recent advances in machine learning for predicting the properties of composites and the environmental-economic implications of material are reviewed. The progress and challenges of BC–cement composites are discussed and potential directions for exploration are provided. Therefore, it is recommended to explore commercialization pathways tailored to local conditions and to develop machine learning models for performance prediction and life-cycle analysis, thereby promoting the widespread application of BC in industry and construction. Graphical Abstract

Background and objectiveAutophagy is a natural process regulated by autophagy-related genes in eukaryotic cells that involves the degradation of cytoplasmic proteins and old or damaged organelles via the lysosomal pathway to help maintain cell homeostasis. Previous studies have suggested a potential association between autophagy and migraine, while the underlying mechanisms remain unclear. This review seeks to evaluate the possible involvement of autophagy in the pathophysiology of migraine, aiming to clarify its role and implications for future research and therapeutic strategies.MethodsA search in PubMed was conducted for English-language articles until December 5, 2024. Key terms of “autophagy,” “migraine,” “microglia,” “neurogenic inflammation,” “central sensitization,” “mitophagy” and “neuropathic pain” in different combinations.ResultsIn the context of migraine, the activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB/Akt) signaling pathway exerts a direct influence on the mammalian target of rapamycin (mTOR), leading to a reduction in autophagy levels. Moreover, the stimulation of purinergic ligand-gated ion channel type 7 receptor (P2X7R) in microglia can hinder autophagy by interfering with the fusion of autophagosomes and lysosomes, which impedes the degradation of substrates within the autophagolysosome. Increased levels of calcitonin gene-related peptide (CGRP) may also modulate autophagy through the Akt/mTOR or protein kinase A (PKA)/mTOR signaling pathways. Additionally, research indicates that mitophagy may be partially impaired in individuals suffering from migraine. Furthermore, autophagy could contribute to the dysregulation of synaptic plasticity by influencing the processes of long-term potentiation (LTP) and long-term depression (LTD), both of which are associated with central sensitization in chronic migraine.ConclusionThese findings suggest that autophagy may play an important role in the pathophysiology of migraine, particularly in its development and central sensitization. Research on autophagy modulators related to migraine will provide valuable insights for treatment strategies.

This study systematically investigated the influence of different blending ratios of recycled powder and slag powder on hydration heat evolution and mechanical properties. Various modern microscopic testing techniques were employed to quantitatively characterize hydration products and microstructures, revealing their hydration mechanisms. The results indicate that both recycled powder and slag powder can accelerate the early hydration rate. When recycled powder and slag powder are co-blended, their early hydration rate and cumulative heat release surpass those of specimens with single additions of recycled powder. Moreover, the mechanical properties in the later stage are superior to those of specimens with single additions of recycled powder. At 60d, the PRS70–1–2 in the multi doped recycled powder and slag powder system even exceeds that of the uni doped SL system, but is much higher than that of the uni doped RP system，the compressive strength of the multi doped recycled powder and slag powder system increased by 25.5 %, 37.1 % and 36.9 %, respectively, compared with that of the uni doped RP system. Specimens with single additions of recycled powder and slag powder have a relatively high proportion of harmful and very harmful pores. At 28d, the porosity of the multi doped recycled powder and slag powder system decreased by 19.2 %, 24.2 % and 14.8 %, respectively, compared with that of the uni doped RP system. However, when recycled powder and slag powder are co-blended, the proportion of harmful and very harmful pores decreases, while the proportion of less harmful and harmless pores increases. This leads to an overall reduction in porosity and an improvement in mechanical properties.

The durability of concrete roads in mountainous regions may be reduced due to underground water infiltration and surface water erosion within highway tunnels. A promising solution is the use of pervious concrete as a drainage subgrade layer to drain away the water, and then to prevent water-induced pavement damage of pavement. For pervious concrete to be an ideal drainage layer for high-traffic loads, it must have compressive strength and permeability coefficient exceeding 25 MPa and 15 mm/s, simultaneously. However, traditional pervious concrete tends to emphasize either in high-strength or high-permeability, depending on its porosity. This study introduces an innovative proportion design method of pervious concrete, which enables higher compressive strength and permeability coefficient by adjusting its skeleton structure, and thus catering to high-traffic load applications. In addition, the workability and setting time of pervious concrete were optimized according to the local environmental conditions, facilitating large-scale and efficient paving of the drainage subgrade. As a result, a drainage subgrade layer with a 28-day compressive strength of 26.43 MPa and permeability coefficient of 18.86 mm/s was successfully applied in a highway tunnel. This study provides a theoretical framework and technical support for widespread application of pervious concrete in drainage subgrade of high-traffic load road.

Internal curing using super-absorbent polymers (SAPs) is an effective method to mitigate the autogenous shrinkage of cement paste. However, conventional SAPs, such as acrylamide/acrylic sodium copolymer, often leave voids in situ after water release, causing significant strength reduction. To address this issue, we developed a low-shrinkage hydrogel (BMH) synthesized using hydrophobic n-butyl methacrylate, which prevents volume collapse by enhancing polymer network stability and maintaining stable interfacial bonding with the cement matrix. Adding just 1 % BMH nearly eliminated autogenous shrinkage at 7 days by significantly reducing capillary stress and resulted in a 64.1 % reduction in crack area compared with conventional SAPs. The no-collapse characteristic of BMH ensures a wider and more uniform distribution of the internal cured region, effectively avoiding in-situ void formation and reducing strength loss (low as 20.7 %), and the conventional SAP leads to 34.9 % strength loss with 1 % SAP addition. The utilization of engineered hydrogel with hydrophobic component provides a novel strategy to reduce deformation and cracking sensitivity of cement-based materials without severe strength reduction.

Abstract The economical production of 5‐aminolevulinic acid (ALA) has recently received increasing attention for its extensive use in agriculture. In this study, a strain of Bacillus cereus PT1 could initially produce ALA at a titre of 251.72 mg/L by using a hydrolysate mixture of low‐cost cassava residue and fish waste. The integration of endogenous hemA encoding glutamyl‐tRNA reductase led to a 39.30% increase in ALA production. Moreover, improving cell permeability by deletion of the LytR‐CpsA‐Psr (LCP) family gene tagU led to a further increase of 59.73% in ALA production. Finally, the engineered strain B. cereus PT1‐hemA‐ΔtagU produced 2.62 g/L of ALA from the previously mentioned hydrolysate mixture in a 7‐L bioreactor. In a pot experiment, foliar spray of the ALA produced by B. cereus PT1‐hemA‐ΔtagU from the hydrolysates increased salt tolerance of cucumber by improving chlorophyll content and catalase activity, while decreasing malondialdehyde content. Overall, this study demonstrated an economic way to produce ALA using a microbial platform and evidenced the potential of ALA in agricultural application.

Due to the limited application of the natural river sand in China, recycled sand (RS) has been considered as an important replacement of natural sand in sustainable construction. The morphology of recycled sand is critical to its effective application in mortar and concrete. An environmentally friendly approach is introduced in this work to improve the morphology of recycled sand during its crushing process. This paper presents a newly developed image acquisition device, which obtained 25,328 RS images to use as a dataset for the construction of a segmentation model based on deep learning technology with an automatic segmentation of RS characteristics. Evaluation indices including accuracy (ACC), Recall, intersection over union (IoU), and F1-score index are reaching up to 99.8%, 88.1%, 84.9% and 84.3%, respectively. RS morphological characteristics including the flat and elongation ratio (FER), angularity index (AI), roundness (R) are automatically extracted by the proposed model, and the predicted results agreed well with the experimental ones. Finally, the effect of FER of RS on mortar’s mechanical properties is investigated by a series of experiments. Results reveal that the flowability, flexural strength and compressive strength of mortar decreased invariably with the lower FER of sand.

Migraine is a common disease of the nervous system that seriously affects the quality of life of patients and constitutes a growing global health crisis. However, many limitations and challenges exist in migraine research, including the unclear etiology and the lack of specific biomarkers for diagnosis and treatment. Electroencephalography (EEG) is a neurophysiological technique for measuring brain activity. With the updating of data processing and analysis methods in recent years, EEG offers the possibility to explore altered brain functional patterns and brain network characteristics of migraines in depth. In this paper, we provide an overview of the methodology that can be applied to EEG data processing and analysis and a narrative review of EEG-based migraine-related research. To better understand the neural changes of migraine or to provide a new idea for the clinical diagnosis and treatment of migraine in the future, we discussed the study of EEG and evoked potential in migraine, compared the relevant research methods, and put forwards suggestions for future migraine EEG studies.

Summary Gamma‐aminobutyric acid (GABA) and delta‐aminolevulinic acid (ALA), playing important roles in agriculture, medicine and other fields, are multifunctional non‐protein amino acids with similar and comparable properties and biosynthesis pathways. Recently, microbial synthesis has become an inevitable trend to produce GABA and ALA due to its green and sustainable characteristics. In addition, the development of metabolic engineering and synthetic biology has continuously accelerated and increased the GABA and ALA yield in microorganisms. Here, focusing on the current trends in metabolic engineering strategies for microbial synthesis of GABA and ALA, we analysed and compared the efficiency of various metabolic strategies in detail. Moreover, we provide the insights to meet challenges of realizing industrially competitive strains and highlight the future perspectives of GABA and ALA production.

This study is undertaken to explore the relationship between the reaction products and the drying shrinkage of alkali-activated slag (AAS) with the varying hydroxide dosage. AAS pastes were firstly produced with either Al(OH)3 or Mg(OH)2 to investigate the effects of hydroxide on the composition of reaction products and the drying shrinkage of AAS. Secondly, the main reaction products formed in AAS pastes, viz. C4AH13, M4AH10, C-S-H, C-A-S-H and C-M-S-H, were synthesized individually. Synthetic products were then taken to cast the respective paste sample to examine the performance against the drying exposure. The results show that adding Mg(OH)2 indeed improved the shrinkage resistance of AAS. This is primarily connected to the increased crystalline phases, namely the hydrotalcite-like phases and the unreacted Mg(OH)2. Whereas adding Al(OH)3 did not relieve the drying shrinkage of AAS as the interlayer spacing of C-A-S-H was enlarged, which in turn allowed for more shrinkage. Further, the investigation of individual synthetic products illustrates that their drying shrinkage scales satisfied the following order: C4AH13

Evaluation of tumor-host interaction and intratumoral heterogeneity in the tumor microenvironment (TME) is gaining increasing attention in modern cancer therapies because it can reveal unique information about the tumor status. As tumor-associated macrophages (TAMs) are the major immune cells infiltrating in TME, a better understanding of TAMs could help us further elucidate the cellular and molecular mechanisms responsible for cancer development. However, the high-dimensional and heterogeneous data in biology limit the extensive integrative analysis of cancer research. Machine learning algorithms are particularly suitable for oncology data analysis due to their flexibility and scalability to analyze diverse data types and strong computation power to learn underlying patterns from massive data sets. With the application of machine learning in analyzing TME, especially TAM’s traceable status, we could better understand the role of TAMs in tumor biology. Furthermore, we envision that the promotion of machine learning in this field could revolutionize tumor diagnosis, treatment stratification, and survival predictions in cancer research. In this article, we described key terms and concepts of machine learning, reviewed the applications of common methods in TAMs, and highlighted the challenges and future direction for TAMs in machine learning.

Fiber extraction and segmentation are critical to identifying the distribution of short fibers in fiber reinforced concrete. This work presents a new segmentation model based on the DeepLab V3 + network for automated probabilistic segmentation of fibers embedded in glass fiber reinforced concrete (GFRC) images obtained from micro-computed tomography (Micro-CT). A total of 2700 sliced images (715 × 715 pixels) are prepared by Micro-CT scanning and data augmentation, of which 2400 are for training with the remaining 300 for validation. It is shown that the proposed model can accurately and effectively segment the fibers in GFRC. The efficiency of the proposed segmentation model is accessed by three metrics of accuracy, intersection over union, and F1-score index, and they are reaching up to 99.3%, 80.4% and 67.2%, respectively. Moreover, the model can achieve a better segmentation than the traditional deep learning models. With good qualitative prediction, the proposed approach shows promise for predicting fiber segmentation based on unlabeled data obtained in the field. Finally, three-dimensional distribution of short fibers in GFRC samples with size of 2.99 × 2.99 × 2.99 mm3 is developed for reconstruction analysis.

Impressed current cathodic protection (ICCP) was widely applied for the corrosion control of reinforced concrete. During the ICCP treatment, the anodic reactions happened on the primary anode surface may induce acidification and subsequently pH drop in the vicinity of the anode, leading to damage of the external anode mortar. In this study, the relationship between the applied current (simulating ICCP treatment) on the Ti mesh anode and pH alterations in simulated concrete pore (SCP) solution (with/without chlorides) was investigated. It was found that the applied current slightly reduced the corrosion resistance of Ti mesh; this negative effect was more pronounced in the presence of chlorides. The pH value of SCP solution near Ti mesh anode decreased when the external current was applied. The consumption rate of OH– ion was higher in the chloride-containing SCP solution. A mathematical model was proposed between the electric charge quantity (Q) and OH– concentration (cOH–) in SCP solution near Ti mesh anode. This model is a useful tool to quantitatively identify the acidification damage induced by impressed current from the perspective of pH alternation near Ti mesh anode.

The influence of organic solvents on the structural integrity and properties of activated kaolinite were compared and analyzed via characterization techniques and molecular dynamics (MD) simulation. The results revealed that the organic intercalators can be easily inserted into the interlayer spaces of activated kaolinite within a short time of the wet ball milling. The DMSO intercalated kaolinites maintained structural integrity due to the high intercalation rate and the excellent buffering effect against the crushing force of milling during the delamination/exfoliation process. The delaminated layers of the DMSO–kaolinite complex exhibited a high specific surface area of 99.12 m2/g and a low average thickness of 35.21 nm. The calculated elastic properties of the organo-kaolinite complex manifested the intercalation of DMSO into a kaolinite interlayer, which could improve the compressibility and structural integrity of kaolinite nanosheets. The DMSO–kaolinite complex was easier to peel off when compared to the other organic intercalators due to its more intercalated molecules.

Recycled powder is a kind of powder particle with a particle size of less than 75 μm produced in the process of preparing recycled aggregate from construction waste with concrete and brick as the main components. It has the potential to replace part of cement as an auxiliary cementitious material. This has important engineering application value for promoting the full-component and high-quality utilization of construction waste, which meets the needs of national sustainable development. Based on the physical and chemical characteristics of recycled powder, the preparation process and basic properties of the recycled powder were systematically analyzed. Based on the low activity of recycled powder, different methods of its activity excitation were described in detail. In addition, some existing problems in the current research were also prospected.

To assess the effect of relative humidity (RH) on drying-induced damage in concrete, the non-uniform strains and microcracks in concrete under different RH conditions were obtained using the digital image correlation (DIC) technique and lattice fracture model. The simulated non-uniform displacements were consistent with those captured using DIC. A new damage index was proposed by considering all the subsets with equivalent strain larger than the threshold tensile strength. The calculated damage index showed good correlation with the microcracks' total area and indicated that RH equal or lower than 55% could cause relatively high cracking risk. This work provides an attractive method for quantifying drying-induced damage in concrete using the DIC technique.

Methods and materials that effectively remove heavy metals, such as lead and copper, from wastewater are urgently needed. In this study, steel slag, a low-cost byproduct of steel manufacturing, was utilized as a substrate material for carbon nanotube (CNT) growth by chemical vapor deposition (CVD) to produce a new kind of efficient and low-cost absorbent without any pretreatment. The synthesis parameters of the developed CNT–steel slag composite (SS@CNTs) were optimized, and its adsorption capacities for Pb(II) and Cu(II) were evaluated. The results showed that the optimal growth time, synthesis temperature and acetylene flow rate were 45 min, 600 °C and 200 sccm (standard cubic centimeter per minute), respectively. The SS@CNTs composite had a high adsorption capacity with a maximum removal amount of 427.26 mg·g−1 for Pb(II) and 132.79 mg·g−1 for Cu(II). The adsorption proceeded rapidly during the first 15 min of adsorption and reached equilibrium at approximately 90 min. The adsorption processes were in accordance with the isotherms of the Langmuir model and the pseudo-second-order model, while the adsorption thermodynamics results indicated that the removal for both metals was an endothermic and spontaneous process. This study showed that compared with other adsorbent materials, the SS@CNTs composite is an efficient and low-cost adsorbent for heavy metals such as lead and copper.

Oil well cement is a type of natural brittle material that cannot be used directly in cementing operations. Fiber is a type of material that can effectively improve the strength and toughness of cement stone, and hybrid fiber materials can more effectively improve the performance of a cement sample. To overcome the natural defects of oil well cement, the new mineral fiber, i.e., wollastonite fiber, and common carbon fiber were used in oil well cement, and the micromorphology, mechanical properties, and stress-strain behavior of the cement were evaluated. The experimental results show that carbon fiber and wollastonite fiber are randomly distributed in the cement paste. The mechanical properties of the cement paste are improved by bridging and pulling out. The compressive strength, flexural strength, and impact strength of cement stone containing only carbon fiber or wollastonite fiber are higher than those of the pure cement, but too many fibers are not conducive to the development of mechanical properties. A mixture of 0.3% carbon fiber with 6% wollastonite fiber in oil well cement slurry results in a greater increase in compressive strength, flexural strength, and impact strength. In addition, compared with blank cement stone, the strain of the mixed cement stone increases substantially, and the elastic modulus decreases by 37.8%. The experimental results supply technical support for the design of a high-performance cement slurry system.

Basalt Fiber Reinforced Polymer (BFRP) bars have bright potential application in concrete structures subjected to marine environment due to their superior corrosion resistance. Available literatures mainly focused on the mechanical properties of BFRP concrete structures, while the bond-slip behavior of BFRP bars, which is a key factor influencing the safety and service life of ocean concrete structures, has not been clarified yet. In this paper, effects of BFRP bars size, corrosion age, and concrete strength on the bond-slip behavior of BFRP bars in concrete cured in artificial seawater were investigated, and then an improved Bertero, Popov, and Eligehausen (BPE) model was employed to describe the bond-slip behavior of BFRP bars in concrete. The results indicated that the maximum bond stress and corresponding slip decreased gradually with the increase of corrosion age and size of BFRP bars, and ultimate slip also decreased sharply. The ascending segment of bond-slip curve tends to be more rigid and the descending segment tends to be softer after corrosion. A horizontal end in bond-slip curve indicates that the friction between BFRP bars and concrete decreased sharply.