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关键词： Class activation mapping   Second-order gradient   Differential evolution algorithm   Visual explanation  

摘要： Class activation mapping (CAM) is key to understanding how convolutional neural networks (CNNs) make decisions, but current approaches face considerable challenges. First-order gradient-based methods are often affected by noise and are prone to gradient saturation, leading to less accurate localization. These methods also tend to rely on manual selection and merging of feature maps, limiting their ability to leverage complementary information across network layers and resulting in weaker visual explanations. To address these issues, we propose a smooth second-order gradient class activation mapping (SSG-CAM) method. By incorporating second-order gradients, SSG-CAM captures changes in feature importance to alleviate gradient saturation and integrates a smoothing technique to reduce noise. Additionally, SSG-CAM is integrated with the differential evolution (DE) algorithm to create a collaborative DE-SSG-CAM optimization framework, which automatically screens and fuses the optimal combination of multi-level feature maps. Extensive experiments on multiple benchmark tasks, including weakly supervised object localization and semantic segmentation, demonstrate that our method outperforms existing baselines across various metrics. Notably, the DE-SSG-CAM framework demonstrated a mean Intersection over Union (mIoU) of 62.38% in the complex task of localizing malarial parasite lesions in red blood cells, highlighting its exceptional performance in biomedical image analysis. In this study, we present an accurate and robust visual explanation tool, offering an innovative approach for automatically distilling optimal visual interpretations from deep neural networks.

关键词： Free fibula flap   Reconstructive surgery   Facial reconstruction   Fibula harvesting  

摘要： Background The free fibula flap (FFF) is a cornerstone in facial skeletal reconstruction, but its harvest may be challenging in 5-10% of cases due to concerns over vascularization. While lower limb CT angiography is widely used to assess vascular patency, it involves ionizing radiation and iodinated contrast, posing risks, especially for patients with renal insufficiency or allergies. This study investigates the use of stock fibula models, derived from average anatomical measurements, as a reliable alternative to patient-specific fibulae for surgical planning, thereby eliminating the need for CT angiography. The safeness of fibula harvesting is guaranteed by US color Doppler. Methods A total of 40 fibulas (20 male, 20 female) were analyzed using DICOM data obtained from standard CT scans. Data segmentation and measurement were performed by an open source software (3Dslicer). Results Statistical analysis showed significant differences in fibular dimensions between genders (p < 0.00001), with minimal variability (CV Width M: 8.66%, CV Thickness M: 10.43%, CV Width F: 10.88%, CV Thickness F: 14.43%), confirming the suitability of stock models for accurate reconstructive plans. Importantly, bypassing CT angiography eliminates radiation exposure and the administration of iodinated contrast, reducing patient risks. Conclusions The results suggest that stock fibula models, based on population averages, provide an effective and safe solution for facial reconstruction, ensuring high surgical precision without the need for CT angiography or contrast *** of Evidence: Level III, risk / prognostic study.

关键词： Activated charcoal   Whitening toothpaste   Toothbrushing simulation   CAD/CAM   Hybrid ceramic   Feldspathic ceramic   Lithium disilicate ceramic   Resin nanoceramic   Surface roughness   Digital volumetric loss  

摘要： Objective Activated charcoal (AC) toothpaste has gained popularity for its whitening properties. However, its abrasive effect on computer-aided design and computer-aided manufacturing (CAD/CAM) surfaces compared to conventional whitening toothpaste (WH) remains unclear. This study aimed to evaluate and compare the abrasive impact of AC and WH toothpastes on the surfaces of CAD/CAM materials. Materials and methods A total of ninety-six specimens were prepared from four different types of CAD/CAM materials: Feldspathic ceramic (Vita Mark II, Group VM), lithium disilicate-reinforced glass ceramic (IPS *** CAD, Group EMC), polymer-infiltrated network hybrid ceramic (Vita Enamic, Group VE), and resin nanoceramic (Lava Ultimate, Group LU). Each specimen was prepared to a thickness of 2 mm and manually polished. Initial surface roughness was determined with profilometric analyses. The materials were then divided into subgroups (n = 8) based on three different brushing mediums: distilled water (DW), whitening toothpaste (WH), and activated charcoal toothpaste (AC). A toothbrushing simulator was used to simulate short-term (10,000 cycles-10k, about 1 year) and long-term (30,000 cycles-30k, about 3 years) brushing. After simulation, roughness measurements were repeated on the brushed surfaces, and changes in surface topography were evaluated using scanning electron microscopy images. Volumetric loss was calculated via digital volumetric analyses. Two-way repeated mixed analysis of variance was conducted to assess the effects of material type, brushing medium, and brushing time on the surface roughness, with significance set at alpha = 0.05. Results Group VM exhibited a significant increase in surface roughness after 10k cycles with AC, surpassing the clinical threshold (Ra > 0.2 mu m). EMC showed no change at 10k but demonstrated a statistically significant increase at 30k cycles, also exceeding the threshold. Hybrid ceramics displayed increased roughness values, but all re

关键词： CAD drawing completion   point cloud   curvature-driven   masked Autoencoder  

摘要： The loss of geometric information in computer-aided design (CAD) drawings presents a significant obstacle to creating high-fidelity digital models. To address this, we propose a novel self-supervised completion method. Our approach begins by converting 2D CAD drawings into a structured 3D point cloud, where the geometric attributes of primitives are uniquely encoded into a meaningful depth dimension. At the core of our method is a masked autoencoder framework empowered by a pivotal curvature-driven adaptive mechanism. This mechanism guides the model to intelligently preserve and reconstruct critical details by focusing on high-curvature regions like corners and intersections during both encoding and decoding. Our method demonstrates superior restoration performance across diverse corruption scenarios on the FloorPlanCAD dataset. Furthermore, its learned features show powerful generalization, achieving state-of-the-art 94.01% accuracy on the ModelNet40 classification benchmark.

关键词： crassulacean acid metabolism   halophyte   ice plant   photosynthetic light reactions   plastoquinone pool redox state   soil salinity  

摘要： Progressive soil salinisation is a major constraint to agriculture, and deciphering resistance strategies in plants adapted to such harsh environments has the potential for improving salinity tolerance in crops. Efficient regulation of the photosynthetic light reactions is a key element of acclimation to adverse environmental conditions, as it ensures optimal production of reducing power and ATP. The annual halophyte Mesembryanthemum crystallinum has long served as a model plant for studying stress response mechanisms. In this species, exposure to salt stress induces a transition from C3 photosynthesis to crassulacean acid metabolism (CAM). This review summarises the latest findings on the regulation of photosynthetic electron transport (PET) under salinity in M. crystallinum, focusing on their potential dependence on CAM. It also suggests a model in which the plastoquinone pool plays a major role in PET acclimation.

关键词： Coronary artery disease (CAD)   Stenosis   Coronary computed tomography angiography (CCTA)   Radiomics   CAD-RADS   Machine learning   Atherosclerotic plaque  

摘要： Synthesizing coronary radiomic data to obtain a single patient-wise Coronary Artery Disease-Reporting and Data System (CAD-RADS) score remains challenging. This work proposes four strategies for summarizing radiomic features extracted from 2779 multiplanar reconstruction images derived from coronary computed tomography angiography of 238 patients. A cascade pipeline was developed to train gradient boosting classifiers for CAD-RADS scoring through consecutive tasks, considering 80%-20% training/test split with five-fold cross-validation on the training set. Two statistical-based and two majority voting approaches were implemented to obtain patient-level classification. The former consisted in computing features average, minimum, maximum and standard deviation, across the coronary images, leading to intermediate coronary classification, followed by patient classification according to the worst coronary class. The latter consisted in single image predictions and the application of majority voting either to all the images, to obtain patient classification (MV_P), or to the images of single coronary arteries, followed by patient classification according to the worst coronary class (MV_C). Majority-voting approaches outperformed statistical-based ones, with MV_P achieving an AUC of CAD-RADS_0 = 0.94, CAD-RADS_1 = 0.92, CAD-RADS_2 = 0.97, CAD-RADS_3 = 0.77, CAD-RADS_4 = 0.88, CAD-RADS_5 = 0.85, and MV_C of CAD-RADS_0 = 0.82, CAD-RADS_1 = 0.78, CAD-RADS_2 = 0.84, CAD-RADS_3 = 0.96, CAD-RADS_4 = 0.98 and CAD-RADS_5 = 0.85. This study represents a significant advancement toward robust and reproducible coronary radiomics tools for automated CAD-RADS scoring.

关键词： crassulacean acid metabolism   gene expression   photosynthesis   circadian clock   stomatal movement   water-use efficiency   drought stress  

摘要： Crassulacean acid metabolism (CAM) is a specialized photosynthetic pathway that enhances water-use efficiency by temporally separating nocturnal CO2 uptake from daytime decarboxylation and carbon fixation. To uncover the regulatory mechanisms coordinating these temporal dynamics, we generated high-resolution, 48 h time-course transcriptomes for the CAM model Kalanchoe fedtschenkoi under both 12 h/12 h light/dark (LD) cycles and continuous light (LL). A rhythmicity analysis revealed that diel light cues are the dominant driver of transcript oscillations: 16,810 genes (54.3% of annotated genes) exhibited rhythmic expression only under LD, whereas just 399 genes (1.3%) remained rhythmic under LL. A smaller set of 3009 genes (9.7%) oscillated in both conditions, indicating that the intrinsic circadian clock sustains rhythmicity for a limited subset of the transcriptome. A gene co-expression network analysis revealed extensive integration between circadian clock components, core CAM pathway enzymes, and stomatal regulators, defining regulatory modules that coordinate metabolic and physiological timing. Notably, key hub genes associated with post-translational and post-transcriptional regulation, including the E3 ubiquitin ligase HUB2 and several pentatricopeptide repeat (PPR) proteins, act as central nodes in CAM-associated networks. This discovery implicates epigenetic and organellar regulation as previously unrecognized critical tiers of control in CAM. Together, our results support a regulatory model in which CAM rhythmicity is governed by both external light/dark cues and the endogenous circadian clock through multi-level control spanning transcriptional and protein-level regulation. To support community exploration, we also provide an interactive eFP (electronic Fluorescent Pictograph) browser for visualizing time-resolved gene expression profiles.

关键词： Prison   TB LON   Incarcerated individuals   Intervention   High-risk population  

摘要： Background Correctional centers, including prisons and other penitentiary facilities, are recognized as high-risk environments for tuberculosis (TB) transmission due to overcrowding and limited access to healthcare. In Nigeria, the situation is worsened by infrastructural inadequacies and delays in the judicial process, which contribute to structural risk factors. These conditions heighten the vulnerability of incarcerated individuals to TB and position prisons as potential reservoirs for active transmission. This study compared the screening efficiency and tuberculosis case yield of two screening approaches (digital chest X-ray with computer-aided detection (CAD4TB) and the WHO-recommended four-symptom screen (W4SS)) implemented in penitentiary institutions, with the aim of informing their broader application in similar high-risk settings. Methods TB Screening was carried out in 17 adult correctional centers across 11 states in Nigeria under the USAID-funded TB LON 1&2 project implemented by KNCV Nigeria. With the successful engagement of prison authorities and relevant approvals obtained, healthcare personnel within the facilities received training to support TB screening efforts. Screening procedures were structured through an orderly and stepwise workflow to cover all cells within each institution. Incarcerated individuals were screened using either digital chest X-ray with computer-aided detection (CAD4TB) or the WHO-recommended four-symptom screen (W4SS). Individuals identified as presumptive TB cases had their sputum samples collected and tested. Confirmed TB patients were promptly linked to treatment. Data analysis was done with the TB Screening efficiency cascade and SPSS version 27.0. Results A total of 26,615 incarcerated individuals were screened between January and August 2022. Among them, 4,162 were identified as presumptive TB (16% yield), and 4,158 underwent evaluation (99.9% evaluation rate). Of the number evaluated, a total of 468 TB cases were con

关键词： age   percutaneous coronary intervention   stable angina   stable coronary artery disease   treadmill exercise time  

摘要： ORBITA-2 (Objective Randomized Blinded Investigation With Optimal Medical Therapy of Angioplasty in Stable Angina) was the first randomized placebo-controlled trial to show the efficacy of percutaneous coronary intervention (PCI) in patients with stable angina and single- or multivessel coronary artery disease without background antianginal medication. Whether the effect is consistent across age groups is unknown.