Search Results (453)

Automated segmentation of the left and right ventricles (LVs and RVs) in cine cardiac MRI (CMR) underpins reliable volumetry and mass estimation. However, papillary muscles and trabeculae (PM/T) introduce clinically meaningful variability and exacerbate cross-dataset domain shift. We present VentrEX, an anatomically guided pipeline. The core segmenter, VentrEX-Seg, is a 3D encoder-decoder with parallel channel-spatial attention and a Transformer bottleneck. Training is performed exclusively on ACDC. A lightweight PM/T module automatically extracts papillary and trabecular burdens and standardizes cavity volumes. External evaluation is zero-shot (no fine-tuning) on Sunnybrook (LV) and MM-WHS MRI (RV). We report Dice, HD95 (mm); for volumetry, we use Bland-Altman analyses (LV and RV volumes). Attention/Grad-CAM visualizations support interpretability. On ACDC, VentrEX achieved higher Dice and lower boundary error than U-Net, nnU-Net, CBAM, and VentrEX-Seg. Zero-shot performance was preserved externally (e.g., Sunnybrook LV Dice 0.9053, HD95 4.95 mm; MM-WHS RV Dice 0.9236, HD95 6.61 mm). Patient-level Bland–Altman analyses characterized LV and RV volumetric agreement. Qualitative overlays and 3D reconstructions showed fewer PM/T “leaks” and anatomically plausible borders across ED/ES. Single-source training with dual zero-shot external tests demonstrates robustness under domain shift. The combination of parallel attention and a Transformer bottleneck enables accurate, transparent cine-CMR segmentation across datasets. Full article

Background: Despite advances in prostate cancer (PC) radiotherapy, including intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic body radiotherapy (SBRT), genitourinary (GU) and gastrointestinal (GI) toxicities remain important complications. Identifying reliable predictors is essential for personalized treatment. Objective: The aim of this study was to summarize current evidence on clinical, dosimetric, immunological, and genetic predictors of acute and late GU and GI toxicities after PC radiotherapy. Materials and Methods: A structured literature review of studies published between 2000 and 2026 was conducted using PubMed, Scopus, and Europe PMC. Eligible studies included clinical investigations, randomized controlled trials, meta-analyses, and reviews assessing toxicity according to RTOG and/or CTCAE criteria. Results: GU toxicity was associated with pretreatment International Prostate Symptom Score (IPSS), large prostate volume, prior TURP, smoking, alpha-blocker use, and bladder/urethral dose. GI toxicity correlated with rectal dose–volume parameters, anorectal irradiation, anticoagulant therapy, and cardiovascular comorbidities. Acute grade ≥ 2 toxicity predicts late toxicity. Preliminary data from small single-center cohorts associate elevated IL-6, TGF-β1, TNF-α, and systemic immune-inflammation index with higher toxicity risk, and higher lymphocyte counts with lower risk; these findings require prospective validation. The PROSTOX radiogenomic signature is promising for the prediction of late GU toxicity but still requires independent external validation in larger, ethnically diverse cohorts with longer follow-up, and is not currently suitable for routine clinical decision-making. Conclusions: GU and GI toxicities have distinct predictive profiles. Integrating clinical, dosimetric, immunological, and genetic factors may improve personalized radiotherapy, although prospective multicenter validation remains necessary. Full article

Verifying the as-built conformity of reinforcing stirrups is challenging due to occlusion and noise inherent in 3D laser scans. Addressing the limitations of manual inspection and the data dependency of deep learning, this paper proposes an unsupervised, design-driven workflow for automated quality inspection. We first introduce the pose adjustment step to refine orientation, followed by utilizing the slice-based projection to decompose the complex point cloud into candidate clusters. Subsequently, a greedy detect-and-remove strategy is applied to iteratively extract individual stirrup instances. To evaluate alignment reliability, we develop a soft similarity metric based on probabilistic volumetric overlap. This measure robustly quantifies the geometric consistency between CAD templates and noisy fragments, accommodating partial data loss where traditional methods fail. Comprehensive experiments on real-world and synthetic datasets demonstrate that the proposed method significantly outperforms unsupervised baselines. The framework maintains high robustness even with only 25% of data retained, providing a precise, efficient solution for the digital quality control of precast components. Full article

Reliable electricity supply in Colombia’s Non-Interconnected Zones requires sustainable and low-cost energy technologies. Vertical-axis hydrokinetic turbines are promising for this purpose; however, their relatively low power coefficient remains a major challenge. This study combines transient 2D and 3D $k$–$\omega$ SST computational fluid dynamics (CFD) simulations with hydraulic channel experiments to investigate a hybrid Darrieus–Savonius turbine. A 27-case Design of Experiments (DoE) based on 2D CFD was first applied to screen the effects of rotor radius ratio (RR), attachment angle (AA), and water velocity. Within the investigated design space, the configuration with $\mathrm{R}\mathrm{R}=0.5$ and $\mathrm{A}\mathrm{A}=0^{\circ }$ produced the most favorable average performance. The selected configuration was subsequently analyzed using 3D CFD and experimentally evaluated at TSR values of 1.0, 1.1, and 1.2. At TSR = 1.0, the 3D model predicted ${\mathrm{C}}_{\mathrm{P}}=0.1525$, closely matching the experimental value of 0.1541 with a relative error of 1.05%. The results demonstrate that 2D CFD is useful for computationally efficient parameter screening and qualitative trend identification, but it overpredicts absolute performance because it neglects blade tip vortices, spanwise flow, and volumetric wake interactions. Three-dimensional CFD is therefore required for reliable performance prediction and analysis of the complex flow structures governing hybrid hydrokinetic turbine behavior. Full article

Objectives: To assess the clinical viability of compressed sensing magnetization, we prepared a rapid acquisition gradient echo (CS-MPRAGE) for brain volume measurement by comparing its scan time and image quality with standard MPRAGE. Methods: In this retrospective study, we analyzed a total of 40 morphologically normal MRIs from relatively young subjects (mean age 27.03 ± 5.02, range 19~40, F:M = 33:7) who underwent both CS-MPRAGE and standard MPRAGE. MRI was performed with a 3T MR scanner using a 64-channel head coil. Volumetric data analysis was conducted using commercial AI-powered quantification software. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR_{gray matter/white matter}) were measured and compared. Qualitative analysis based on overall image quality, deep gray matter delineation, artifacts, and gray–white matter differentiation was rated on a five-point visual scoring system. Statistical analyses included paired t-tests, intraclass correlation coefficients (ICCs) and Pearson correlation. Results: CS-MPRAGE had a significantly shorter scan time than standard MPRAGE (1:46 vs. 5:20 min; p < 0.001). Whole-brain volume was similar (standard-MPRAGE, 1176.89 ± 105.36; CS-MPRAGE, 1181.14 ± 105.62 mL; r = 0.988; ICC, 0.9754–0.9931). Gray matter and regional lobe volumes were comparable, while the white matter volume was slightly larger with CS-MPRAGE. CNR of the gray–white matter was significantly higher with CS-MPRAGE (left, 30.45 ± 11.21 vs. 49.53 ± 32.71; right, 30.73 ± 11.97 vs. 46.89 ± 30.40; p = 0.0001) while SNR were similar across key brain regions. Conclusions: CS-MPRAGE provides high-quality 3D images and reliable volume data with significantly reduced acquisition time and comparable image quality. Full article

This narrative methodological review aims to critically assess whether current AJCC/UICC N3-defining criteria for nasopharyngeal carcinoma (NPC) represent validated biological and statistical thresholds or pragmatic staging boundaries. Specifically, it examines the evidential basis of the >6 cm nodal-size threshold, extension below the caudal border of the cricoid cartilage, and advanced radiologic extranodal extension (rENE), with emphasis on the distinction between prognostic-variable validity and threshold validity. The >6 cm criterion is a historically inherited threshold that predates contemporary MRI-based staging and may insufficiently capture the three-dimensional complexity of nodal tumor burden. Similarly, defining inferior nodal extension by the caudal border of the cricoid cartilage improves anatomical reproducibility compared with earlier lower-neck definitions, yet it remains a pragmatic imaging landmark rather than a validated biological boundary for lymphatic dissemination. By contrast, advanced rENE is more biologically informative because it reflects invasive tumor behavior; nonetheless, its staging utility depends on standardized imaging definitions, interobserver reliability, external validation, and incremental clinical utility. Emerging imaging-derived descriptors—including MRI-based nodal diameter, nodal volume, middle-neck involvement, total tumor volume, and integrated imaging–biological models—underscore the limitations of relying exclusively on single categorical thresholds. Future N3 refinement should move beyond substituting one cutoff for another by characterizing nodal descriptors in continuous, ordinal, volumetric, or severity-graded forms before adopting simplified categories. Future refinement of NPC nodal staging will likely require approaches that move beyond isolated anatomical thresholds and better account for the multidimensional nature of nodal disease, including tumor burden, spatial distribution, invasive characteristics, and biological risk. Full article

Background and Objectives: The aim of this study was to evaluate the volume of dental tissue removed during conventional versus microscope-assisted coronal access cavity preparation by an undergraduate student in extracted mandibular incisors, and to compare the volumetric assessment capabilities of cone beam computed tomography (CBCT) and intraoral scanner (IOS) for this application. Materials and Methods: Thirty extracted mandibular incisors were randomly allocated to two equal groups: Group 1 (G1), access cavity preparation without magnification; and Group 2 (G2), access cavity preparation with the aid of an operating microscope. Volumetric analysis was performed using CBCT (RAYSCAN^® Alpha Plus 130) and an intraoral scanner (3Shape TRIOS^® 3) before and after access cavity preparation. Volume loss was calculated for each group. Differences in groups were assessed using the independent-samples Student’s t-test for CBCT data and the Mann–Whitney U test for IOS data. Reproducibility between methods was evaluated using the intraclass correlation coefficient (ICC). Results: The CBCT analysis revealed significantly greater tissue loss in G1 (mean 14.93 mm³, SD 4.42) than in G2 (mean 7.64 mm³, SD 2.72) (mean difference 7.29 mm³, 95% CI, 4.54–10.04; p < 0.001; Cohen’s d = 1.99, 95% CI, 1.10–2.88). The IOS analysis did not detect a statistically significant between-group difference (G1: mean 5.37 mm³ vs. G2: mean 4.55 mm³; p = 0.436). The ICC for volume loss between methods was 0.011 (95% CI: −0.150 to 0.237), below the threshold conventionally used to indicate acceptable reliability; because CBCT and IOS did not sample identical anatomical extents, this should be interpreted as limited agreement specific to the present protocols rather than general evidence of poor concordance between the two imaging methods. Conclusions: Within the limitations of this exploratory, single-operator in vitro study, microscope-assisted access cavity preparation resulted in significantly less CBCT-measured volumetric tissue loss than conventional access in mandibular incisors. Full article

Fucoxanthin is a high-value marine xanthophyll with a unique epoxy-allene structure, predominantly produced by brown macroalgae and marine diatoms, and additionally reported in other heterokont lineages including chrysophytes and certain haptophytes. As a core light-harvesting pigment, it exhibits multiple bioactivities including lipid-lowering, antioxidant, and anti-inflammatory effects, with broad applications in functional foods, dietary supplements, and pharmaceuticals. Currently, over 70% of commercial fucoxanthin is extracted from brown macroalgae such as Saccharina japonica and Undaria pinnatifida. However, due to low endogenous pigment content and significant extraction losses, the industrial yield is only 0.05–0.1% of dry weight, failing to meet the growing downstream demand for stable high-purity supply. Marine diatoms, characterized by short growth cycles, high pigment content, and controllable culture conditions, have emerged as a core direction for industrial upgrading. Among them, Phaeodactylum tricornutum and Odontella aurita are the two most systematically studied high-yield strains with outstanding potential. This review adopts volumetric productivity (mg/(L·d)) as the core evaluation metric, which integrates biomass concentration, pigment content, and production cycle, and reflects industrial efficiency more reliably than single intracellular content data. We summarize high-yield induction methods from the dimensions of nutrient regulation, light optimization, exogenous induction, and strain improvement, and systematically compare downstream processing, safety profiles, and regulatory status between the two diatoms. Furthermore, we evaluate multi-product co-production potential and scale-up performance from a techno-economic perspective. This review provides a side-by-side benchmark of these two marine diatoms, offering a data-driven reference for process development and industrial deployment of microalgae-derived fucoxanthin. Full article

Rapid conversion of agricultural land into low-density housing reshapes local water balances at a time when climate change is intensifying hydrological extremes in Central Europe. This study evaluates the rooftop rainwater harvesting (RWH) potential of a newly urbanized housing estate in Rokietnica (Greater Poland Voivodeship, Poland) using a publicly available true orthophoto (5 cm ground sampling distance) as a reliable geometric data source. Roof footprints of 41 single-family buildings (5305 m² in total) were manually vectorized in QGIS and combined with monthly precipitation recorded at the nearest meteorological station (Złotniki) in a simplified volumetric model (V = A × R × C, with C = 0.95). To place the single reference year (2021) in its climatic context, the full 72-year precipitation record (1952–2023) was analyzed using the Mann–Kendall test and Sen’s slope estimator. The results indicate a harvestable volume of approximately 2642 m³ in 2021 (53–73 m³ per building; mean 64 m³), with May and August jointly accounting for almost one-third of the annual total. Annual precipitation at Złotniki exhibits a statistically significant increasing trend (+1.29 mm yr⁻¹; p = 0.028) concentrated in winter and early spring, while summer totals remain trendless but highly variable. A monthly storage simulation driven by the recent 30-year record (1994–2023) shows that summer garden irrigation, the dominant practical application of harvested rainwater in Polish households, is considerably harder to meet from the roof alone than year-round indoor non-potable uses: a 5 m³ tank covers approximately 73% of the seasonal demand of a 100 m² garden plot, while a 3–5 m³ tank would theoretically secure 91–98% of toilet-flushing demand for a four-person household. Under Poland’s national rainwater co-financing scheme (formerly “Moja Woda,” active 2020–2024, succeeded by “Mikroretencja” from June 2026), simple payback periods of roughly 3–7 years make household installations financially defensible. The findings suggest that true orthophotos enable rapid, low-cost RWH assessments in dynamically developing suburbs, and that storage sizing should anticipate the ongoing seasonal redistribution of precipitation under climate change. To our knowledge, this is the first study to combine free national true-orthophoto imagery, a 72-year Mann–Kendall trend analysis, and a subsidy-linked storage-reliability simulation within a single suburban rainwater-harvesting assessment. Full article

Encoder-decoder segmentation networks use skip connections to recover spatial detail, but direct feature transfer can also propagate irrelevant high-frequency responses into the decoder. This problem is pronounced at weak or irregular tumor margins, where contour evidence is useful but should not modify semantically reliable features indiscriminately. We propose Bridge-Net, a boundary-ambiguity guided residual injection framework for two-dimensional brain tumor MRI segmentation. Bridge-Net formulates boundary enhancement as a conditional feature-correction problem. A structural boundary prior is coupled multiplicatively with an ambiguity map obtained from an auxiliary foreground logit. The ambiguity cue is deterministic and probability-based, rather than a Bayesian or calibrated uncertainty estimate. The overlap between the two cues identifies locations that are both boundary-like and prediction-ambiguous. A level-specific gated residual branch then injects the resulting cue into each skip feature, while a zero-initialized bounded scaling factor preserves an identity-like main pathway at the start of optimization. Experiments were conducted on TCGA-LGG and BRISC2025 under dataset-specific protocols, including patient-level partitioning for TCGA-LGG and the official image-level split for BRISC2025. Bridge-Net achieved Dice/IoU/HD95 values of 84.16%/73.65%/15.38 on TCGA-LGG and 87.26%/77.63%/8.68 on BRISC2025. Patient-level paired analysis on TCGA-LGG and image-level paired analysis on BRISC2025 further supported the improvements over UCTransNet. Ablation results support the complementary roles of structural boundary and probability-ambiguity cues, and a same-seed repeated-run comparison across reproduced models supports the stability of the observed performance trend under the tested setting. Relative to UCTransNet, the proposed mechanism increases the parameter count from 7.982 M to 7.988 M and FLOPs from 24.083 G to 24.196 G at $256\times 256$ resolution. These results indicate that ambiguity-filtered boundary residual fusion introduces only a small increase in parameter count and FLOPs for boundary-ambiguous MRI segmentation, although broader patient-level and volumetric validation remains necessary. Full article

Compacted graphite iron (CGI) is widely used in thermomechanically demanding engineering applications owing to its high thermal conductivity, vibration-damping capacity, and machinability. However, its surface performance can be limited under the simultaneous effects of elevated temperature, sliding contact, and corrosive environments. In this study, CGI surfaces were subjected to pack boriding using a silica-free B₄C–NaBF₄ powder mixture at 800, 900, and 1000 °C for 4 h, and the microstructural characteristics of the resulting boride layers, together with their wear behavior at room temperature and 500 °C and their electrochemical corrosion resistance, were systematically investigated. Cross-sectional SEM/EDS analyses revealed the formation of boride layers exhibiting a saw-tooth interface morphology, with thickness increasing from 44 ± 4 µm to 108 ± 9 µm with increasing boriding temperature. XRD results indicated the formation of a dual-phase FeB/Fe₂B structure in all borided specimens, with the Fe₂B phase dominant at 800 °C and the FeB phase becoming dominant at 1000 °C. Boriding increased the surface hardness from approximately 470–480 HV to a range of 2122–2550 HV. In room-temperature wear tests, specimens B1 and B2 exhibited specific wear rates approximately 13-fold lower than that of the untreated CGI, whereas B3 showed a higher wear loss attributable to the brittle character of the FeB phase. At 500 °C, B1 maintained the most balanced tribological performance, with the lowest volumetric wear loss and coefficient of friction, while microcracking and three-body abrasion effects became more pronounced in B2 and B3. In electrochemical tests conducted in 3.5 wt.% NaCl solution, B1 exhibited more stable open-circuit potential behavior, whereas B3 showed the highest resistance in terms of Tafel kinetics, with the lowest corrosion current density and corrosion rate. Overall, the results demonstrate that the Fe₂B-dominant boride layer obtained at 800 °C provides the most balanced performance among hardness, wear, and corrosion behavior, whereas the thick, FeB-dominant layer formed at 1000 °C, despite offering high hardness and favorable corrosion kinetics, may compromise tribological reliability owing to its brittleness, increased surface roughness, and tendency toward microcracking. Full article

Accurate reservoir performance assessment increasingly relies on hydrological model-derived inflow series; however, the effects of hydroclimatic forcing pathways on reservoir design outcomes remain insufficiently understood. This study evaluates the sensitivity of reservoir performance to alternative forcing pathways by comparing observed inflows with SWAT+-simulated streamflow driven by ERA5-Land reanalysis data in the Cidadelhe catchment, Portugal. An integrated hydrology–reservoir modeling framework couples SWAT+ simulations with three analytical approaches: Behavior Analysis, the Modified Sequent Peak Algorithm (MSPA), and the Resilience-Regulated MSPA-2024. Results show that, despite strong hydrological model performance (NSE up to 0.83), SWAT+-simulated inflows exhibit systematic attenuation of variability, approximately 20–25%, leading to substantially lower storage capacity (up to 60–65%) and evaporation estimates relative to those derived from observed data. While volumetric reliability remains largely insensitive to forcing pathways, resilience, sustainability, and drought risk indices display pronounced method-dependent behavior. MSPA-2024 demonstrates strong robustness by maintaining near-invariant performance metrics across forcing conditions through embedded resilience constraints. These findings show that inflow statistical structure, rather than mean flow alone, controls reservoir design outcomes and that forcing-pathway consistency is critical for reliable performance assessment. The proposed SWAT+–MSPA-2024 framework supports more reliable model-based reservoir planning, particularly in data-scarce basins and climate-scenario applications. Full article

3D bioprinting requires control of environmental conditions within the printing chamber, as temperature affects bioink rheology, printability and cell viability. However, the spatial temperature distribution inside bioprinting enclosures remains poorly characterised, limiting the understanding of thermal gradients that may affect process stability. In this work, the spatial thermal behaviour of a previously developed controlled chamber was evaluated using a multi-point temperature acquisition system. Temperature was monitored at 45 locations distributed throughout the chamber volume under controlled conditions at 37 °C after thermal stabilisation. The results revealed vertical and lateral thermal gradients associated with natural convection and forced air recirculation, together with local non-uniformities influenced by fan operation. Nevertheless, comparatively homogeneous temperature regions were identified within the printing zone, indicating suitable areas for more stable and reproducible biofabrication processes. Additionally, a three-dimensional CFD model incorporating the internal air volume, two 200 W electrical heaters, two axial recirculation fans, and simplified representations of the printhead and build platform was developed to represent an operational chamber configuration. The model was used to visualise the spatial temperature distribution within the enclosure, including the thermal field around the internal printer components. The proposed approach provides a practical experimental framework for the volumetric characterisation of thermal conditions in bioprinting environments, contributing to the design and optimisation of controlled chambers and improving the reliability of biofabrication processes. Full article

Longitudinal mapping of the superficial peripheral vascular network is clinically relevant for conditions such as venous insufficiency, superficial venous thrombosis, and localized hemorrhagic injury; yet existing modalities are either operator-dependent, costly, or unable to provide wide-field coverage. We designed and demonstrated the feasibility of a relatively quick, cost-effective, automated panoramic near-infrared (NIR) imaging system operating at 850 nm, with a total acquisition time of 30 s. The prototype integrates a motorized rotational acquisition frame, co-localized illumination, lateral mirror enhancement, and a time-of-flight ranging sensor. A custom image processing pipeline combining contrast-limited adaptive histogram equalization (CLAHE), black-hat morphological filtering, Otsu binarization, structure-tensor-based diameter quantification, and photogrammetric 3D reconstruction was applied to data from five healthy volunteers. Optimal acquisition parameters (30 ms exposure, analog gain 3.5) were identified via systematic characterization. The pipeline reliably isolated venous structures of the 35 cm field of view, yielding a mean superficial vein diameter of 2.69 ± 1.48 mm, consistent with published anatomical references. A panoramic texture-mapped 3D surface reconstruction of the limb was generated for each participant. The system provides a rapid, operator-independent panoramic view of superficial veins suitable for future longitudinal monitoring, offering a compelling complementary tool to duplex ultrasound for tracking morphological and volumetric vascular changes. Full article

Background: Ultrasound-guided radiofrequency ablation (RFA) has become an established minimally invasive treatment for selected benign and autonomously functioning thyroid nodules. Although clinical outcomes are well documented, the biological mechanisms underlying tissue remodeling after ablation remain incompletely characterized. The integration of imaging, molecular, and histopathological data may provide a more comprehensive understanding of treatment response. Methods: We conducted a prospective monocentric observational translational cohort study including 60 patients undergoing ultrasound-guided RFA for benign or autonomously functioning thyroid nodules between November 2024 and December 2025. Patients underwent standardized pre-procedural assessment including high-resolution ultrasound with volumetric evaluation, three-dimensional reconstruction, and collection of peripheral blood samples for exploratory extracellular vesicle (EV)-derived microRNA (miRNA) profiling. Clinical outcomes, volumetric changes, vascular remodeling, and procedural complications were assessed during scheduled follow-up visits (mean follow-up duration: 11 months; range: 5–17 months). A subgroup of patients who subsequently required surgery because of insufficient volumetric response underwent thyroidectomy, allowing histopathological evaluation of post-ablation tissue changes. Clinical, imaging, molecular, and pathological data were integrated within a multimodal translational framework. Results: RFA resulted in a mean nodule volume reduction of 56% at early follow-up, with progressive volumetric reduction observed during longitudinal ultrasound evaluation. A clinically relevant improvement in compressive symptoms was observed, with a 44% reduction in symptom burden. Doppler ultrasound demonstrated progressive changes in vascular patterns consistent with post-ablation devascularization and tissue remodeling. Ten patients underwent thyroidectomy after RFA because of insufficient volumetric response, providing histological validation of treatment-induced tissue alterations, including coagulative necrosis, fibrosis, inflammatory changes, and architectural remodeling. Exploratory EV-derived miRNA profiling was incorporated into the translational workflow to investigate potential molecular correlates of treatment response; however, molecular findings require further validation in larger cohorts. Conclusions: This study provides a multimodal translational characterization of tissue response after thyroid RFA by integrating clinical outcomes, ultrasound imaging, histopathology, and exploratory EV-derived miRNA analysis. The proposed framework may contribute to a deeper understanding of biological changes following thermal ablation and support future investigations aimed at identifying reliable biomarkers of treatment response. Full article