Search Results (386)

Colorectal cancer (CRC) develops through both conventional adenoma–carcinoma and serrated neoplasia pathways, yet noninvasive screening still under-detects the advanced precursor lesions that enable true cancer prevention. Stool-based screening reduces CRC mortality, but its preventive impact remains constrained by limited detection of advanced precancerous lesions (APLs), including advanced adenomas and sessile serrated lesions. Next-generation multitarget stool DNA assays (mt-sDNA; e.g., Cologuard Plus) have established high sensitivity for CRC and specificity approaching 94%, leaving improved APL detection as the principal opportunity for innovation. This review presents a consensus framework for a multi-omic stool screening paradigm that integrates host epigenetic markers (DNA methylation) with gut microbiome features using artificial intelligence (AI). Multi-omics capture complementary layers of early tumor biology: epithelial shedding and field effects reflected in host methylation signals together with luminal ecological and inflammatory changes represented by microbial features. Evidence from cross-cohort microbiome studies indicates that microbial signatures provide an additive—rather than standalone—axis of information for CRC and its precursor lesions. Because microbiome-based models are highly susceptible to batch effects arising from collection devices, extraction chemistry, sequencing platforms, and bioinformatic pipelines, practical mitigation strategies are outlined, including harmonized pre-analytics, batch-aware study design, leakage-resistant validation, and computational harmonization. A translational roadmap linking analytical validity, locked-model development, and prospective colonoscopy-verified clinical validation is proposed, aligned with TRIPOD + AI, STARD, PROBAST-AI, SPIRIT-AI, CONSORT-AI, and DECIDE-AI reporting standards. Scenario modeling using BLUE-C prevalence estimates suggests that improving APL sensitivity from approximately 43% to 55–65% at ~94% specificity could translate to detecting roughly 13–23 additional advanced precancerous lesions per 1000 individuals screened, highlighting the potential prevention impact of a multi-omic approach. This framework aims to guide developers and clinical investigators toward next-generation stool tests capable of materially improving precursor-lesion detection while maintaining clinically acceptable specificity. Full article

The mechanical behavior of metallic core–shell nanoparticles is critical for their use as reinforcement particles and additive manufacturing feedstocks, yet their deformation mechanisms remain incompletely understood. This study employs molecular dynamics simulations to investigate the compressive response of a Cu-core/Al-shell nanoparticle and compares it with solid Cu, solid Al, and a hollow Al shell of the same size under uniaxial loading along ⟨100⟩, ⟨110⟩, ⟨111⟩, and ⟨112⟩ directions. The single-material nanoparticles show strong anisotropy: solid Cu exhibits orientation-dependent transitions from dislocation slip to deformation twinning, while introducing a void to form a hollow Al shell reduces stiffness and strength, confines plasticity to the shell wall, and suppresses extended load-bearing twins. The Cu–Al core–shell nanoparticle combines these behaviors in an orientation-dependent manner. Under ⟨110⟩ and ⟨112⟩ loading, deformation is largely shell-dominated, whereas ⟨100⟩ and ⟨111⟩ loading more strongly activates the Cu core. Mechanistically, ⟨100⟩ is characterized by Shockley partial activity and junction/lock formation in the Al shell coupled with twinning in the Cu core; ⟨110⟩ shows primarily shell partials with limited core involvement; ⟨111⟩ promotes partial-dislocation activity in both shell and core; and ⟨112⟩ produces localized, twin-dominated bands in the Al shell with shell-thickness-dependent twin extension into the Cu core. These trends are rationalized using Schmid factor considerations for $\left\{111\right\}⟨110⟩$ slip and $\left\{111\right\}⟨112⟩$ partial/twinning shear, together with the effects of faceted free surfaces and the Cu–Al interface. The core–shell geometry enables two concurrent interface-mediated pathways, i.e., (i) stress transfer and reduced cross-interface transmission and (ii) circumferential bypass within the shell, which together yield only slight flow-stress increases over solid Al while markedly reducing stress serrations compared with both solid Cu and solid Al. Across all orientations, the core–shell structures also exhibit delayed yielding (higher yield strain) relative to solid Cu, indicating enhanced ductility. The results provide an atomistic basis for designing Cu–Al core–shell nanoparticles for robust particle-based processing and additive manufacturing feedstock, and for informing multiscale models with mechanism-resolved, orientation-dependent inputs. Full article

This work presents a numerical–experimental validation of aeroacoustic predictions for bio-inspired leading edge serrated blade cascades. Transient simulations were carried out on a four-blade cascade using several turbulence modeling strategies commonly applied in broadband noise analysis—Spalart–Allmaras (SA), k−ω SST, k−ε, Scale-Adaptive Simulation (SAS), and Large Eddy Simulation (LES)—for assessing their capability to reproduce measured spectra. Multiple timestep resolutions were tested to ensure temporal accuracy. The comparison indicates that below 900 Hz, interaction noise is difficult to evaluate for such applications, whereas in the range from 0.9 to 5 kHz the turbulent jet–blade interaction is clearly captured. In the low-frequency regime (<1 kHz), the SA, SAS, and k−ω SST models exhibit similar behavior, while at higher frequencies SAS provides the closest agreement with experimental results, albeit with a slight tendency to overestimate at the upper end of the spectrum. LES demonstrates a satisfactory performance in reproducing the baseline response. The validation of numerical simulations with experimental results has been achieved, and a complex analysis using pressure measurements on the blade surface for a four-blade cascade configuration shows that turbulent formations lose their coherence quite significantly across several frequency bands. Overall, the results confirm that numerical simulations can reproduce the dominant experimental trends, while emphasizing the model-dependent trade-offs in predicting the acoustic benefits of bio-inspired leading edge serrations. Full article

Although the cyclic bending behavior of circular and elliptical steel tubes has been widely studied, the combined effects of major-to-minor axis length ratio and curvature ratio on the deformation characteristics and buckling life of galvanized steel elliptical tubes remain insufficiently understood. This study experimentally investigates the cyclic bending response and failure behavior of galvanized steel elliptical tubes with major-to-minor axis length ratios of 1.5, 2.0, 2.5, and 3.0 under curvature ratios of −1, −0.5, and 0. The curvature ratio is defined as the minimum controlled curvature divided by the maximum controlled curvature. Buckling is defined as the cycle at which a pronounced 20% drop in peak bending moment is observed. The response is characterized by moment (N⋅m)–curvature (m⁻¹) hysteresis and minor-axis variation with curvature, while failure is evaluated using the relationship between curvature range and number of cycles to buckling. The results show that stable elastoplastic hysteresis loops develop for all curvature ratios, with slight cyclic relaxation observed at curvature ratios of −0.5 and 0. Increasing the axis length ratio slightly reduces the peak moment under a fixed curvature ratio. Minor-axis variation increases progressively with cycle number, exhibiting serrated curves at an axis ratio of 1.5 and butterfly-shaped curves at higher axis ratios. Symmetric behavior is observed at a curvature ratio of −1, whereas asymmetric responses occur at −0.5 and 0. The failure results indicate that larger curvature ranges and higher axis length ratios reduce the number of cycles to buckling, while curvature ratios closer to −1 enhance buckling life. On a log–log scale, the relationship between curvature range (m⁻¹) and number of cycles to buckling becomes linear. A theoretical model is proposed and shows good agreement with the experimental results. Full article

Scandium (Sc), when added together with magnesium (Mg), forms a highly effective synergistic pair in aluminum (Al) alloys, enhancing their performance in various applications. While the thermomechanical processing and heat treatment of such Al-Mg-Sc alloys have been well investigated, the behavior and features of their as-cast state remain less understood. In particular, the evolution of cellular/dendritic microstructures and the formation of phases at submicrometric and nanometric scales, especially those developing during solid-state cooling, require further elucidation. The present study employs a combination of conventional and advanced characterization techniques in the Al-5 wt.%Mg-0.4 wt.% Sc alloy, including CALPHAD, optical microscopy, scanning electron microscopy (SEM), transmission and scanning transmission electron microscopy (TEM/STEM) with energy-dispersive spectroscopy (EDS), x-ray diffractometry (XRD), tensile testing, and fractographic analysis. Al-rich dendrites surrounded by Al₃Sc, AlFe, and β-Al₃Mg₂ phases and the formation of primary submicrometric clusters containing AlFe and Al₃Sc have been identified, revealing important microstructural features that depend strongly on the solidification conditions. Moreover, nanometric Al₃Sc precipitates mainly in the form of rod-like structures with sizes in the order of 50–200 nm have been observed within the α-Al matrix during solid-state cooling stage. At higher solidification rates, such as 15.3 °C/s, these precipitates remain predominantly in solid solution, indicating strong solidification rate dependence in the precipitation behavior. Comparisons between alloys containing 0.1 Sc and 0.4 Sc have demonstrated that the morphology, size, and distribution of Sc-rich phases significantly affect the stress–strain tensile response and underlying strengthening mechanisms. Distinct Portevin–Le Chatelier (PLC) effects have been observed, corresponding to very different serration activities in the stress–strain curves comparing both Al-5%Mg-0.4%Sc and Al-5%Mg-0.1%Sc alloy samples. Among the compositions and conditions studied, the Al–5Mg–0.4Sc alloy samples solidified under the fast-cooling condition (11.2 °C/s) exhibited the most improved mechanical performance, attaining a strength of 306 MPa and an elongation of 22.6%, underscoring the pivotal role of Sc content and solidification rate in achieving optimized mechanical properties. Full article

Serrated adenocarcinoma (SAC) represents a molecularly heterogeneous subtype of colorectal carcinoma (CRC) linked to the serrated pathway. It is aimed to clarify the molecular mechanisms underlying SAC development. Digital slides from The Cancer Genome Atlas (TCGA) colorectal adenocarcinoma Firehose Legacy dataset (632 cases) were reviewed, and cases were classified as SAC, partial-SAC, or classical CRC. Genomic alterations, mRNA expression, and DNA hypermethylation were compared using cBioPortal. Enrichment analyses were performed via WebGestalt, and protein–protein interaction (PPI) networks with hub genes were identified using STRING and Cytoscape. Statistical significance was defined as p < 0.05 and q < 0.05. The results revealed that the groups showed significant differences in the expression of 327 genomic alterations, 20 mRNAs, and 21 methylated genes (p < 0.0001, q < 0.0001). Hub genes were PSMC1, FLT3LG, SNW1, H3C2, H1-2, H2BC14, H1-5, RPS16, SUPT5H, and MYOD1. The pathways associated with differently expressed genes were the following: cell structure and morphology (phagocytic vesicle, microvillus, endocytosis, and immobile cilium), protein kinase activity (particularly MAPK), and immunological mechanisms. The hub genes act as molecular bridges connecting the observed genomic and epigenetic variations, particularly driving chromatin-related regulation and MAPK signaling pathways. In particular, PSMC1, SNW1, H3C2, H1-2, and H2BC14 genes offer promising molecular targets for future therapeutic approaches in SACs. Full article

This study examines the mechanical response of medium-manganese TRIP steels under different stress states, focusing on deformation-induced austenite-to-martensite transformation and ageing phenomena. Two steels with distinctly different ferrite–austenite morphologies and retained austenite (RA) fractions were analysed: a globular microstructure with 18% RA and a lamellar microstructure with 14% RA, produced by single (SA) and double annealing (DA), respectively. Continuous and interrupted tests were performed under in-plane shear, uniaxial tension, and plane strain stress states. Strain fields were analysed using high-resolution digital image correlation, while RA fractions were quantified as a function of strain by ex situ X-ray diffraction. The results demonstrate a pronounced stress-state dependence. SA samples exhibit discontinuous yielding, with uniaxial tests showing clear Lüders band formation. Both steels exhibit dynamic strain ageing manifested by Portevin–Le Chatelier (PLC) serrations and associated strain bands, which are most pronounced under uniaxial tension, weaker in plane strain, and barely detectable in in-plane shear. Static strain ageing is also evidenced by a strengthened yield response upon unloading–reloading in all samples. The SA globular microstructure exhibits higher PLC band inclination angles than the lamellar DA microstructure, consistent with its more pronounced anisotropy. The propagation velocity in uniaxial tensile samples decreases with increasing strain following the work-hardening response. For both steels, the austenite-to-martensite transformation rate is highest in uniaxial tension, slightly reduced in plane strain, and strongly suppressed under in-plane shear. A Beese–Mohr/Johnson–Mehl–Avrami–Kolmogorov formulation incorporating stress triaxiality and Lode angle captures these trends for both steels. For the stress states considered, the DA condition exhibits a consistently higher transformation rate than the SA condition, accompanied by a higher work-hardening rate. These findings highlight the coupled role of stress state and microstructural morphology in governing localisation behaviour and strain-induced transformation in medium-manganese steels. Full article

To address the depletion of shallow coal resources, mining activities have progressed to greater depths, where rock masses contain numerous fractures due to complex geological conditions, making grouting reinforcement essential for ensuring stability. Using digital image correlation, this study investigated the strain evolution characteristics of grouted fractured specimens of three rock types—mudstone, coal–rock, and sandstone—under uniaxial compression. Analysis of the strain evolution process focused on two typical fracture inclinations of 0° and 60°, while examination of the peak strain characteristics covered five inclinations, namely 0°, 15°, 30°, 45°, and 60°. The findings indicate that the mechanical response varies systematically with lithology and fracture inclination. The post-peak curves differ significantly among rock types: coal–rock shows a gentle descent, mudstone exhibits a rapid strength drop but higher residual strength, and sandstone is characterized by “serrated” fluctuations. The failure mode transitions from tensile splitting at a horizontal inclination of 0° to shear failure at inclinations of 15°, 30°, 45°, and 60°. Strain nephograms corresponding to the peak stress point D reveal sharp, band-shaped zones of strain localization. The maximum principal strain exhibits a non-monotonic trend, first increasing and then decreasing with increasing inclination angle. For grouted coal–rock and sandstone, the peak values of 47.47 and 45.00 occur at α = 45°. In contrast, grouted mudstone reaches a maximum value of 26.80 at α = 30°, indicating its lower susceptibility to damage. The study systematically clarifies the strain evolution behavior of grouted fractured rock masses, providing a theoretical basis for evaluating the effectiveness of reinforcement and predicting failure mechanisms. Crucially, the findings highlight mudstone’s role as a high-integrity medium and the particular vulnerability of horizontal fractures, offering direct guidance for the targeted grouting design in stratified rock formations. Full article

Colonoscopy is central to colorectal cancer (CRC) prevention, and its effectiveness is determined by the quality of mucosal inspection and lesion detection. The adenoma detection rate (ADR) remains the most widely validated quality benchmark due to its strong inverse association with interval CRC. However, reliance on ADR alone is increasingly recognized as insufficient, particularly given the growing understanding of the serrated neoplasia pathway, which contributes up to one-third of sporadic CRCs. This has driven the emergence of complementary metrics, such as the sessile polyp detection rate (SPDR) and adenomas per colonoscopy (APC). Although SPDR offers important advantages for capturing serrated pathology, challenges persist, including interobserver variability, inconsistent pathology thresholds, limited endoscopist training, and the absence of standardized benchmarks. Alongside these evolving metrics, technological advancements such as image-enhanced endoscopy, computer-aided detection, high-definition optics, and distal attachment devices have demonstrated measurable improvements in detecting subtle lesions and reducing operator-dependent variability. Large real-world registries, including GIQuIC, now support the development and validation of composite models that integrate ADR, SPDR, and APC to better reflect the full spectrum of neoplasia detection. As the field advances, redefining colonoscopy quality will require reconciling established metrics with newer indicators that more comprehensively address both conventional adenomas and serrated lesions. Full article

This study proposes a novel framework for quantifying curved grain boundaries that overcomes key limitations of existing methods. Unlike Fourier-based approaches that require labor-intensive sequential analysis of individual boundaries and selectively represent only high-amplitude regions, or spline-based methods that demand complex parameter selection for interpolation points, the proposed framework integrates curvature variance filtering with U-chord curvature calculation to enable automated, comprehensive, and noise-resistant characterization of grain boundary morphology. The curvature variance filtering adaptively determines smoothing parameters based on local curve properties, while the U-chord curvature method ensures rotational invariance and robustness against digitization errors. Four heat treatment processes were applied to GH4169 alloy, producing distinct grain boundary morphologies with mean curvature (MC) values ranging from 0.0625 to 0.1252. Controlled cooling alone (Process A) yielded predominantly straight boundaries (91.06% straight, 0.12% serrated), while re-dissolution treatment (Process D) produced the highest serration degree (58.81% straight, 3.53% serrated). The quantitative analysis reveals that dispersed δ-phase precipitation creates discrete pinning points, forming serrated boundaries with sharp curvature peaks, whereas dense, parallel δ-phase arrays at specific angles produce coordinated wavy undulations. This framework provides a reliable quantitative tool for optimizing heat treatment protocols to achieve target grain boundary configurations in nickel-based superalloys. Full article

Shale pores and throats are key factors controlling the enrichment and development efficiency of shale oil and gas. However, the characteristics and formation mechanisms of shale pores and throats remain unclear. Taking the Permian continental shales in the Mahu Sag of the Junggar Basin as an example, this paper studies the formation mechanisms of pores and throats in shales of different lithofacies through a series of experiments, such as high-pressure mercury injection and scanning electron microscopy. The results show that the Permian continental shales in the Junggar Basin are mainly composed of five lithofacies: rich siliceous shale (RSS), calcareous–siliceous shale (CSS), argillaceous–siliceous shale (ASS), siliceous–calcareous shale (SCS), and mixed-composition shale (MCS). The pores in shale are dominated by intergranular and intragranular pores. The intergranular pores are mainly primary pores and secondary dissolution pores. The primary pores are mainly slit-like and polygonal, with diameters between 40 and 1000 nm. The secondary dissolution pores formed by dissolution are irregular with serrated edges, and their diameters range from 0.1 to 10 μm. The throats are mainly pore-constriction throats and knot-like throats, with few vessel-like throats, overall exhibiting characteristics of nanometer-scale width. The mineral composition has a significant influence on the development of pores and throats. Siliceous minerals promote the development of macropores, and carbonate minerals promote the development of mesopores. Clay minerals inhibit pore development. Diagenesis regulates the development of pores and throats through mechanical compaction, cementation, and dissolution. Compaction leads to a reduction in porosity, and cementation has varying effects on the preservation of pores and throats. Dissolution is the main factor for increased pores and throats. These findings provide a lithofacies-based geological framework for evaluating effective porosity, seepage capacity, and shale oil development potential in continental shale reservoirs. Full article

Background: Appendiceal neoplasms are rare, but recent data indicate a rising trend, particularly in patients under the age of 50. These tumours are often diagnosed incidentally during histopathological examination. This study has aimed to examine the incidence and histological subtypes of appendiceal neoplasms in a Southern Hungarian population. Methods: Our study included neoplastic appendix specimens processed at the University of Szeged between 2014 and 2023. Results: Neoplasms were identified in 71 cases from 3640 appendectomies (1.9%). Benign lesions were present in 37% of cases (n = 26), with the most common subtype being the sessile serrated lesion (n = 20). Mucinous and malignant neoplasms were found in 63% of cases (n = 45), most frequently low-grade appendiceal mucinous neoplasm (n = 19), followed by neuroendocrine tumour (n = 17). Notably, colorectal neoplasm was identified in 50% of benign, and 42.2% of mucinous and malignant cases during a mean follow-up of 33.4 months. Significant associations were found between histological subtype and age (p = 0.022), complete resection (p = 0.012), presence of vascular invasion (p = 0.007), and localisation of potentially associated colorectal carcinoma (p = 0.018). Additionally, tumour dignity showed significant correlations with tumour, node, metastasis (TNM) stage (p < 0.001), vascular invasion (p = 0.017), and lastly, occurrence (p = 0.031) and localisation (p = 0.003) of associated colorectal carcinoma. Conclusions: The prevalence and characteristics observed in this Southern Hungarian population were consistent with international data, although raw case numbers suggested an upward trend. The high rate of associated colorectal neoplasms underscores the importance of thorough pathological evaluation and long-term surveillance. Full article

Currently, the synonymy of the two morphologically analogous copepod species, Mongolodiaptomus birulai (Rylov, 1922) and M. formosanus Kiefer, 1937, remains doubtful. While examining the detailed morphology of diaptomid copepods from China, Cambodia, and Vietnam, we came across two undescribed species whose morphology is closely similar to that of M. birulai from Northeast China and M. formosanus from Taiwan. In this paper, descriptions of M. parabirulai sp. nov. from Yunnan, Southwestern China, and M. longiserratus sp. nov. from Cambodia and Vietnam are presented. The first new species, M. parabirulai sp. nov., can be distinguished from its congeners in the male P5 by it having the distal outer portion of the second right exopod produce a wing-shaped expansion and its strongly robust left and right basis. The second new species, M. longiserratus sp. nov., can be differentiated by the following characteristics in the male: the spiniform process on segment 20 of the right antennule is longer than that of segment 21 and has a serrate outer margin, and the right P5 basis has two (longitudinal and semicircular) hyaline lamellae. Furthermore, the status of M. birulai and M. formosanus is reviewed and recommended. Full article

An in-depth study of the genetic mechanisms of graphite in shear zones is crucial for understanding crustal weakening and the origins of inorganic carbon. This research focuses on mylonitic marble (MM) and cataclastic marble (CM) from the Tongyuanpu shear zone of Eastern China. The occurrences, nanostructures, carbon sources, and genesis of graphite were systematically investigated through micro- to ultra-microscale analysis. The results reveal that the MM contains two graphite varieties: C-foliation-aligned bands and stylolite-derived serrated aggregates. Both exhibit strong Z-axis LPO, indicating a deformation temperature below 200 °C. In contrast, the CM features individual graphite particles within fragmented grains. Near-ideal graphite structures are characterized in both types; however, a higher TOC content and a greater graphitization degree are observed in the CM. Raman thermometry indicates metamorphic peak temperatures of 588–673 °C (MM) and 540–682 °C (CM), with the former showing a significant discrepancy from the EBSD results. The δ¹³C_ORG values (−12.21‰ to −8.06‰) suggest fluid-derived carbon sources. We propose that reduction reactions involving high-temperature metamorphic fluids supplied the essential carbon source. Ductile shearing accelerated the graphitization of these carbonaceous materials through the accumulation of local strain energy, while subsequent brittle deformation with frictional sliding further facilitated structural transformation. Full article

Large Strain Extrusion Machining (LSEM) is an intensive plastic deformation process evolved from conventional machining, enabling effective control over chip morphology and grain refinement. This process often generates high cutting temperatures and frictional instability during machining, which degrades material properties and accelerates tool wear. This study proposes a technique combining microtextured tools with LSEM to optimize cutting performance. By designing different microtextured tools (parallel-to-cutting-edge microtextured tools (P-T) and perpendicular-to-cutting-edge microtextured tools (V-T)), cutting experiments were conducted on 7075 aluminum alloy to systematically investigate the effects of microtextured LSEM on cutting performance and chip formation. Results indicate that microtextured tools effectively reduce cutting temperatures. Compared to non-textured tools (N-T), microtextured tools can lower maximum cutting temperatures by up to 13.20% (36.56 °C). Microtextured LSEM suppresses serration formation, leading to more stable chip formation. The serration degree of chips produced by microtextured tools was reduced by up to 25.66% compared to N-T tools. XRD analysis indicates that microtextured tools significantly increase chip dislocation density, reaching nearly 2.77 times that of N-T tools, enhancing material microhardness and refining grain size. This study confirms that combining microtextured tools with LSEM synergistically optimizes chip morphology and improves the microstructural properties of Al7075, providing technical support for machining high-strength aluminum alloys. Full article