Search Results (268)

(1) Background: Drug-eluting bead transarterial chemoembolization (DEB-TACE) is increasingly used for unresectable colorectal liver metastases (CRLM), yet individualized prognostic tools are lacking. We developed and internally validated nomograms predicting overall survival (OS) and hepatic progression-free survival (hPFS). (2) Methods: In this single-center retrospective cohort, reported per the TRIPOD guideline, OS and hPFS were estimated by Kaplan–Meier methods, and independent predictors from multivariable Cox regression were assembled into nomograms. Internal validation combined 1000-sample bootstrap optimism-corrected concordance indices (C-index), a uniform shrinkage factor, a bootstrap calibration slope, and a LASSO–Cox sensitivity analysis. (3) Results: Among 63 patients (44 deaths; 42 intrahepatic-progression events), median OS was 10.9 months and median hPFS was 5.8 months. Independent OS predictors were baseline CEA, high liver tumor burden (≥10 lesions), CEA decline (protective), and second-line-or-beyond interventional therapy (corrected C-index: 0.796). Independent hPFS predictors were high liver tumor burden, CEA decline, and age (corrected C-index: 0.718). Nomogram-defined high-risk groups had markedly shorter OS (5.3 vs. 22.8 months) and hPFS (3.3 vs. 8.6 months; both p < 0.001). Grade ≥3 toxicity occurred in 6%. (4) Conclusions: In real-world DEB-TACE-treated CRLM, liver tumor burden and CEA dynamics dominated prognosis; the internally validated nomograms provide individualized estimates and risk stratification, pending external validation. Full article

The study presents a sustainable, metal-free tanning system based on 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and N-methylmorpholine (NMM), which stabilizes collagen through a zero-length crosslinking mechanism. Reactive triazine intermediates, generated in situ, selectively activate collagen carboxyl groups, forming active esters that subsequently react with amine functionalities to form amide bonds. Unlike conventional tanning systems, no metals or toxic chemicals are incorporated into the tanned leather. Optimization of reagent concentration, temperature, and dosing strategy revealed that the gradual formation of reactive intermediates is essential to balance reaction kinetics and diffusion throughout collagen. Under pickle-free conditions, hydrothermal stability was achieved with only 2.5–3.4 wt% CDMT/NMM, yielding shrinkage temperatures of 81–85 °C that surpass most reported chrome-free tanning systems. The resulting leather displayed a bright white appearance, excellent dyeability, and outstanding physical-mechanical performance, including superior tear resistance and competitive tensile strength. These properties are consistent with the formation of a homogeneous collagen network reinforced by direct covalent amide crosslinks while maintaining fiber flexibility. Furthermore, avoiding pickling significantly reduces chemical consumption and improves wastewater biodegradability, enhancing the environmental sustainability of the process. Overall, CDMT/NMM emerges as a scalable, environmentally friendly tanning technology that combines mechanistically controlled collagen crosslinking with excellent leather performance. Full article

The severe early-age shrinkage of alkali-activated slag is a primary bottleneck restricting its engineering application. In this work, a novel shrinkage control strategy is proposed, dominated by the physical control of vacuum dehydration and assisted by the chemical compensation of MgO. The synergistic mechanism of this strategy in the AAS system was revealed by multi-scale characterization methods (XRD, FTIR, TG, NMR, BSE, and pore solution analysis). Firstly, vacuum dehydration greatly advances the development window of capillary pressure to the early stage (<6 h) of the material in the significant viscoelastic stage by forcibly removing free water between the interlayer and capillary pores. Most of the shrinkage strain energy can be dissipated through the early creep behavior of the slurry, and the strong negative pressure induces the conversion of mesopores to macropores, thereby effectively reducing the equilibrium capillary cracking driving force. Secondly, the late hydration of an appropriate amount of MgO generates magnesium silicate and hydrotalcite phases, which provide a continuous chemical micro-expansion for the matrix to compensate for residual shrinkage and moderately optimize the local pore defects induced by dehydration. The results show that in the sodium silicate solution and sodium hydroxide activating system, the synergistic effect reduces the total shrinkage rate of 28 days by 37.86% and 29.26%, respectively. Additionally, the compressive strength of hardened samples increases by about 20%. This study provides a new theoretical basis for the design of low-shrinkage and high-performance alkali-activated materials based on the physical–chemical coupling mechanism. Full article

This paper presents the possibilities of using steel cord from car tires as a structural concrete reinforcement obtained after initial mechanical treatment. The steel wire constituting tire reinforcement after mechanical separation from rubber is not further processed and, in the form partially contaminated with rubber, is stored in landfills. Further processing is usually not economically justified. The purpose of the work is to determine the physical properties of fiber concrete, made of ordinary concrete with the addition of steel fibers recovered from tires, obtained in the process of relatively easy recycling. The work is mainly experimental. The literature review presents the basics of the current state of knowledge regarding the methods of making and testing elements made of fiber-reinforced concrete. In the next part, the authors’ own research and results of testing fiber-reinforced concrete with wires after pre-cleaning are shown. Chapter five summarizes the results of research and juxtaposes the most important observations that can be used for the practical use of fibers obtained in a simple recycling technology. The utilitarian value of the work is to show the practical possibilities of recovery (recycling) of used tires, in particular for the fiber-reinforcement of concrete. Among other things, it was shown that the addition of steel fibers (contaminated with rubber) to approximately 1.3% reduces the shrinkage of concrete with these fibers by 7–10% compared to a fiber-free concrete matrix cured under the same conditions. Full article

Binder jetting (BJ) can avoid crack defects caused by residual thermal stress in the additive manufacturing of high-speed steel (HSS). However, the research on BJ-fabricated HSS remains limited and the printing and sintering processes for M2 HSS are still not well understood. The mechanisms of printing defects and microstructure evolution behavior have not been fully elucidated. In this research, orthogonal experiments are designed and conducted to investigate the effects of layer thickness, inkjet concentration, and powder spreading speed on the forming quality (relative density) of green parts. The types and causes of printing defects are identified and the formation mechanism of layer-shifting defects is analyzed. A method involving an additional printing base is proposed to eliminate layer shifting. An optimized debinding-sintering curve is established and the influence of sintering temperatures (1280–1320 °C) on the relative density, dimensional shrinkage, pore morphology, microstructure, and mechanical properties of BJ M2 HSS is investigated. The transformation mechanisms of carbides are elucidated. The study shows that the BJ M2 HSS achieves a relative density of 99.06% and an average friction coefficient of 0.37 at 1320 °C, with ultimate tensile strength and hardness reaching 858.7 MPa and 628.4 HV. Furthermore, the effects of substrates with different thermal conductivities (graphite and zirconia) on the relative density and warpage of sintered M2 HSS parts are analyzed. The substrates with high thermal conductivity can enhance sintering efficiency but exacerbate deformation. To address this, a graphite-zirconia composite substrate is developed. The results of this study can provide a theoretical foundation for the binder jetting fabrication of high-performance, defect-free M2 HSS. Full article

The long-term productivity of hydraulically fractured deep coalbed methane (CBM) wells is jointly governed by desorption-driven gas supply from the coal matrix, the effective-stress response and time-dependent creep of natural cleats, and the progressive degradation of hydraulic-fracture conductivity. To address the difficulty of conventional models in consistently describing the time-dependent transport capacities of natural cleats and hydraulic fractures, this study develops a productivity-prediction model for hydraulically fractured deep CBM wells that couples gas storage in the coal matrix, dynamic natural-cleat permeability, and dynamic hydraulic-fracture conductivity. Based on mass conservation, the model accounts for free- and adsorbed-gas storage, single-phase gas flow, matrix-fracture mass transfer, and wellbore production. The evolution of natural-cleat permeability incorporates effective-stress-induced closure, Langmuir desorption shrinkage, and fractional-order creep, whereas the evolution of hydraulic-fracture conductivity considers fracture compaction, elastic deformation and embedment of proppants, and creep-induced closure of the coal rock. The nonlinear coupled equations are solved using a fully implicit finite-difference scheme. The field dataset comprises daily production records from six deep CBM wells and is used only to constrain physically reasonable ranges of field parameters and provide reference production characteristics. The results indicate that effective stress primarily controls the rapid closure of flow pathways during the early production stage, while the relative contribution of coal creep increases with production time. Neglecting either coal creep or stress sensitivity leads to an overestimation of cumulative gas production over the medium and long term. The proposed model provides a physically constrained analytical framework for evaluating the long-term productivity of hydraulically fractured deep CBM wells and comparing alternative production strategies. Full article

Production of short-fiber-reinforced carbon/carbon composites (SF-C/C composites) is typically based on the pyrolysis of short-fiber-reinforced plastics (CFRPs) produced by compression molding. The production of C/C composites is generally a highly time- and energy-intensive process, particularly for complex geometries. Injection molding can offer an attractive alternative due to its high level of automation, cost efficiency, and ability to produce complex geometries. However, in contrast to compression molding, the shorter fiber lengths resulting from the compounding process and the parameter/geometry-dependent cavity-filling behavior in injection molding lead to a complex three-dimensional fiber orientation distribution. This can profoundly affect both the pyrolysis behavior of the CFRPs and the properties of the resulting SF-C/C composites. In this study, CFRP plates (150 × 150 × 4 mm³) were injection-molded at varying injection rates and mold temperatures. The influence of these parameters on the properties of the resulting SF-C/C composites was systematically investigated. Characterization included shrinkage and warpage behavior, porosity, microstructure via light microscopy and X-ray computed tomography, and flexural properties. The results show that the homogeneity of fiber orientation within the component is critical for controlling warpage during pyrolysis. In particular, asymmetric flow-line formation leads to non-uniform shrinkage across the thickness and promotes warpage. Therefore, achieving a homogeneous and/or symmetric distribution of the fiber orientation is essential for producing warpage-free SF-C/C composites by injection molding. Full article

Concrete shrinkage is significantly influenced by the restraint level, and cracking often occurs under specific restraint conditions, thereby adversely affecting structural performance. Investigating the effect of restraint on shrinkage cracking is of great significance for enhancing early-age durability and ensuring structural safety. In this study, four distinct restraint levels (0%, 35%, 55%, and 75%) were established by varying the thickness of the inner steel ring. The influence of varying degrees of restraint on the shrinkage behavior was investigated, with digital image correlation (DIC) and internal strain gauge measurement employed to observe the strain and predict the risk of cracking. As the degree of restraint increases, the inner steel ring inhibits the free radial shrinkage of concrete more significantly, thereby inducing greater tensile strains at both the outer circumferential surface and the interior. The surface strain accumulation far exceeds the interior response due to the drying gradient. During the first 60 h, the shrinkage strain measured by both methods exhibited the most rapid evolution, indicating a critical high-risk period for cracking. These results advance the understanding of restraint effects in concrete and comprehensively clarify the relationship between the degree of restraint and the shrinkage, which accurately captures the evolution of shrinkage, facilitates the transition from empirical to quantitative design for crack-resistant materials and supports their customized optimization under practical engineering loading conditions. Full article

Background: Breast cancer treatment is often based on multimodal approaches in locally advanced stages typically including neoadjuvant chemotherapy (NACT). There are limited options for the assessment of prognosis and early identification of future non-responders, which has led to the study of circulating cell-free DNA (cfDNA) and its tumor-derived subset, circulating tumor DNA (ctDNA), for potential use as non-invasive markers for prediction of response and prognosis associated with NACT. Methods: We have evaluated the literature on approaches to the use of cfDNA and/or ctDNA as potential biomarkers for NACT. Results: Out of 142 references going back to 2010, we found there were 87 original research reports, 39 reviews, 10 clinical trial reports and six case reports. A detailed analysis revealed several distinctive ways that markers were evaluated in a clinical setting. The original studies have focused on cfDNA, especially cfDNA integrity, whereby increasing integrity levels correlate with tumor shrinkage, reductions in proliferation markers, and hence indicate a better prognosis. Similarly, epigenetic alterations have shown promising results, with methylated ctDNA levels decreasing in responders. Further studies demonstrated the utility of ctDNA persistence through the NACT as strongly associated with shorter disease-free and overall survival. The most recent approaches of longitudinal ctDNA monitoring were found to be valuable for early identification of patients at high risk for post-operative recurrence. Conclusions: It should be noted that while most reports indicate the important role of circulating DNA in the assessment of prognosis and early detection of recurrence, there is currently only a limited utility in the prediction of eventual neoadjuvant therapy outcomes. Full article

Use of fly ash (FA), a by-product of coal-fired power stations, and basic oxygen furnace slag (BOFS), a by-product of steel production plants, in construction applications in Kazakhstan is limited due to their low quality and inherent problematic properties. For example, the concern with using BOFS as an aggregate in concrete is the volume expansion caused by the formation of calcium hydroxide (Ca(OH)₂) or magnesium hydroxide (Mg(OH)₂) in the concrete matrix generated by a chemical reaction between water and free calcium oxide (f-CaO) or free magnesium oxide (f-MgO) in BOFS. This issue can be addressed through geopolymerization and CO₂ curing (mineral sequestration). Moreover, the quality of FA does not meet ASTM Class F FA criteria (coarse particle sizes and low reactivity). This study investigated the physical, mechanical, microstructural, and durability properties of geopolymer mixtures composed of low-quality FA, ground granulated blast-furnace slag (GGBFS), and BOFS aggregates under various curing conditions. Six distinct curing regimes were assessed: air, water, 6 h steam, 12 h steam, 6 h steam combined with 6 h CO₂, and 6 h steam combined with 12 h CO₂ curing. The hardened properties, durability, and microstructural characteristics of geopolymer mixtures were mainly assessed by compressive strength, dielectric constant (DC), drying shrinkage, expansion (1 M NaOH solution and water expansions), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) images. Test results show that steam curing and combined steam and CO₂ curing significantly enhanced the performance of the mixtures containing BOFS aggregates. The combined steam and CO₂ curing accelerated the mineral sequestration of f-CaO in the BOFS aggregates, increasing the 28-day compressive strength by up to 27.7% and 19.2% (reaching 37.1 MPa) compared to air- and water-cured mixtures (29.1 and 31.1 MPa, respectively). While air (20.0 and 11.7), steam (28.7 and 12.4), and combined steam and CO₂ (23.6 and 12.6) curing at 1-day and 182-day yielded lower DC, water curing (30.5 and 32.2) had higher DC. The extended steam and CO₂ curing times further enhanced compressive strength growth (39.6 MPa) by 36.6% for air-curing and 27.1% for water curing, although curing duration did not significantly affect the dielectric constant. Importantly, the expansion of the BOFS aggregate in both water and 1 M NaOH solution was minimized up to 0.04% under combined curing, mitigating the inherent volumetric instability of the BOFS. Drying shrinkage was also reduced by 0.17% under combined curing conditions. Longer steam and CO₂ curing times reduced variability in dielectric constant, drying shrinkage, and the expansion characteristics. FTIR spectroscopy, SEM image, and XRD analyses confirmed that the mixture’s geopolymerization was more noticeable during the steam and CO₂ curing regimes than during water and air curing regimes. The longer steam and CO₂ curing times promoted extended hydration and the formation of stable carbonate compounds from the BOFS f-CaO, producing a significantly denser and microstructurally stable geopolymer matrix. Full article

Vertisols represent some of the most dynamic pedological systems due to the high content of smectitic clays and the intense shrinkage–swelling processes associated with seasonal variations in humidity. The present work analyzes the dynamics of pedoturbations and the rheological behavior of a smectitic Vertosol located in the Cheglevici experimental field (Aranca Plain, western Romania), continuously monitored for a period of over 50 years (1967–2020). In a stationary experiment, inert markers were buried at depths ranging from 25 to 150 cm to track the vertical displacement of the soil mass. Periodically collected samples were analyzed from a granulometric, mineralogical, chemical, and rheological point of view (plasticity limits, activity index, volumetric shrinkage, free swelling, deformation modulus, cohesion, conventional pressure). The results indicate a high smectite content (69–76%) and rheological indices specific to highly active soils (PI > 35%, A > 1.0, VS > 100%, FS > 140%). The progressive redistribution of the markers provides strong evidence of substantial profile-scale soil redistribution associated with long-term pedoturbation processes, supporting the hypothesis of a near-complete profile turnover over multidecadal timescales. A significant increase in apparent density and a tendency for granulometric homogenization across the profile, associated with structural reorganization, are also highlighted. The study provides long-term experimental evidence on the vertical dynamics of the soil mass in Smectitic Vertisols and reveals major implications for agricultural management, infrastructure stability, and water flow modeling in expansive soils. Full article

Objective: This study aimed to develop a multi-modal ultrasound-based model integrating radiomics, deep learning, and clinical features to predict progression-free survival (PFS) in diffuse large B-cell lymphoma (DLBCL) with superficial lymph node involvement. Methods: A total of 281 DLBCL patients with superficial lymph node involvement treated with standard regimens were retrospectively enrolled and assigned to training and test sets at a 7:3 ratio. Ultrasound radiomic features were extracted by PyRadiomics, and deep learning features were derived from DenseNet121 with transfer learning. After Pearson’s correlation filtering and least absolute shrinkage and selection operator (LASSO)-Cox regression for feature selection, five prognostic models were compared using C-index, time-dependent Area Under the Curve (AUC), risk stratification and decision curve analysis. Results: The combined model achieved the highest C-index of 0.811 in the test set, with 1-/2-/3-year PFS AUCs of 0.826, 0.812, and 0.810, respectively. Risk stratification showed significantly poorer PFS in the high-risk group (p < 0.01). A visualized nomogram was further developed as a preliminary reference for individualized prediction. Conclusions: This multi-modal combined predictive model and corresponding nomogram based on superficial lymph node features showed promising potential for practical and intuitive prognostic assessment and risk stratification in DLBCL. Full article

The study aimed to develop and preliminarily characterize experimental resin-based dental composites (RBCs). In addition to the composites, didodecyldimethylammonium bromide (DDAB) was used as a biocide in various concentrations (0–3 wt%). Hardness (HV), flexural strength (FS), and modulus of elasticity, as well as diametral tensile strength (DTS) of composites, were examined. Additionally, shrinkage stress, surface free energy (SFE), water sorption (Wsp), and solubility (Wsl) were determined. Cytometric analysis, including biocidal surface testing and susceptibility to colonization by Streptococcus mutans, Escherichia coli, and Candida albicans, assessed antibacterial activity. The HV of RBCs varied from 27.2 ± 1.5 to 31.5 ± 1.8 depending on DDAB amount, FS—67.0 ± 16.1 MPa for control composite and 79.2 ± 14.5 MPa for modified composite. All DTS values exceed 24 MPa. Shrinkage stress is highest for the composite with 0.25 wt% DDAB—18.5 ± 1.9 MPa—and lowest for the composite with 1 wt% DDAB—15.0 ± 2.5 MPa. Wsp is lowest in the control group (37.19 ± 1.69 µg/mm³) and highest for 1 wt% modifier (42.11 ± 2.75 µg/mm³). Wsl was at its lowest in control group (1.98 ± 1.58 µg/mm³), and highest for modification with 1 wt% (3.91 ± 1.74 µg/mm³). For RBCs modified with 3 wt% DDAB after 60 min, an increase in dead cells is observed: 51% for Escherichia coli, 71% for Streptococcus mutans, and 24% for Candida albicans. Preliminary results show that DDAB effectively reduced the presence of the tested pathogens and contraction stress; however, at certain concentrations it negatively influences hardness and water sorption of composites. The presented findings highlight both the potential and the limitations of DDAB-modified RBCs and underline the need for further studies, including cytotoxicity and genotoxicity assessments, release analyses and evaluation of composites’ ageing behavior. Full article

The firing of traditional gray pottery relies on complex physicochemical reactions governing its color, dimensional accuracy, and structural stability. Unclear kiln-transformation mechanisms restrict standardized and digital production of this Chinese intangible cultural heritage. Herein, direct ink writing (DIW) was used to fabricate Hejin gray pottery green bodies from local ternary raw materials. Thermodynamic calculations, TG–DTG/DSC, XRD, XRF, and atmosphere-controlled firing tests were combined to reveal coupled phase evolution and reduction color-forming mechanisms during sintering. Two interrelated kiln-transformation processes were identified. First, sequential mineral reconstruction occurs at four critical temperatures: free water loss at 119.8 °C, two-stage dehydroxylation of hydrous silicates at 270.5 °C and 767.9 °C, and CaCO₃ decomposition at 547.9 °C. Uneven shrinkage and gas release at these temperatures induce cracking, blistering, and deformation of printed bodies. Micron-sized CaCO₃ (equivalent radius ≈ 1.31 μm) exhibits high surface energy and significantly reduces its decomposition temperature, consistent with experimental observations. Second, reducing atmospheres trigger competitive phase formation. Distinct from the conventional Fe₂O₃ → Fe₃O₄ → FeO reduction pathway, Fe oxides preferentially react with abundant Al₂O₃ to form thermodynamically stable FeAl₂O₄ spinel, yielding uniform celadon-gray tones. The final color is nearly independent of 20–90 vol% CO, and air-isolated cooling below 600 °C is mandatory to prevent secondary oxidation and reddening. This work establishes a thermodynamic framework for DIW-printed Hejin gray pottery kiln transformation, clarifies microscale defect and color-evolution mechanisms, and offers theoretical guidance for atmosphere-controlled firing and digital mass production of heritage ceramics. Full article

The long-term durability of concrete structures is significantly affected by moisture. Excessive moisture may cause drying shrinkage, crack formation, and accelerated corrosion of embedded reinforcement; therefore, reliable and non-destructive moisture assessment is essential for structural durability evaluation. In this study, a controlled acoustic measurement method and a machine learning-based classification framework are presented for the non-destructive identification of moisture levels in concrete specimens. A magnet-assisted free-fall steel ball mechanism was used to generate standardized impacts instead of conventional manual hammer excitation. To reduce environmental vibration noise and capture internal material responses, acoustic signals were recorded using a piezoelectric contact microphone. Experiments were conducted on concrete specimens prepared at nine moisture levels under both large-sample (BIG) and small-sample (SMALL) conditions. Power Spectral Density (PSD) and Mel-Frequency Cepstral Coefficients (MFCC) were extracted from the recorded impact signals and used as input features. Individual machine learning classifiers were compared with a hybrid stacking ensemble model to evaluate discriminative performance and probabilistic reliability. The results showed that MFCC features provided higher classification performance than PSD features under both dataset conditions. For the BIG specimens, the MFCC-based model achieved an accuracy of 0.9872, whereas the PSD-based model achieved 0.9811. For the SMALL specimens, MFCC reached an accuracy of 0.9822, while PSD achieved 0.9750. The AUC-ROC values of the proposed model ranged from 0.9980 to 0.9996 in the multi-class classification of nine moisture levels. These findings demonstrate that controlled impact acoustics combined with MFCC-based representation and stacking-based ensemble learning provides a rapid, low-cost, and reliable NDT approach for concrete moisture classification. Full article