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关键词： Heuristic modeling metrics   modeling operation evaluation network   modeling sequence recovery   self-supervised pretraining   Heuristic modeling metrics   modeling operation evaluation network   modeling sequence recovery   self-supervised pretraining  

摘要： 3-D modeling technologies play a crucial role in modern manufacturing. 3-D models are often exported as boundary representations for compatibility and data protection, which remove the modeling history and limit editability. To restore modeling sequences from such models, researchers employ neural networks to infer the possible modeling steps. This approach needs a large amount of labeled sequence data, and annotating such data is time-consuming. To address this issue, we propose a self-supervised pretraining method that generates modeling sequences directly from boundary representation models. Training data are first generated using a heuristic modeling sequences generation algorithm. Before training, each B-rep model is preprocessed into a zone graph representation. We then introduce the modeling operation evaluation network, which extracts features and scores each candidate operation to sequentially reconstruct the model. By selecting the most suitable operation at each step, the network progressively reconstructs the modeling sequence. This approach effectively reconstructs modeling sequences, restores the editability of B-rep models, and significantly reduces the reliance on labeled data.

关键词： Bspline   NURBS   Pocket   Smoothing   Dynamic behavior   HSM  

摘要： In recent years, smoothing techniques have emerged as one of the most significant research topics in the field of CAD/CAM. Accordingly, a tool path smoothing approach based on spline trajectories has been developed for pocket milling applications in high-speed machining (HSM). This study proposes an optimization framework for parametric curves employed in the smoothing of CAM milling strategies. The "Morph Spiral" strategy was selected as the case study and modeled using Bspline and NURBS interpolations. The influence of interpolation order and discretization parameters on machine tool dynamics and machining accuracy was systematically investigated. The obtained results indicate that the integration of parametric curves within CAM strategies considerably enhances the efficiency of HSM operations. The optimal configuration was identified as an interpolation order of 2 with a discretization parameter of n = 1000. Under these conditions, the proposed smoothing approach reduced the milling cycle time by approximately 60% for both Bspline and NURBS interpolations, while maintaining acceptable chordal deviations. Increasing the interpolation order from 2 to 5 resulted in a 9.7% increase in chord error for Bspline curves, whereas its effect on NURBS interpolation was negligible. Conversely, increasing the discretization parameter from n = 1000 to n = 3000 led to a reduction in chord error of 64.49% for Bspline and 77.39% for NURBS. These findings confirm the effectiveness of the proposed methodology in optimizing the trade-off between machining accuracy and productivity in freeform high-speed milling applications.

关键词： Artificial intelligence   CAD   Screening   Mammography   Business   Retrospective   Non-inferiority  

摘要： AimThe AI case malignancy score (AI-CMS) represents the AI algorithm's confidence (from 0 to 100%) that a mammography exam is malignant. This work aims to retrospectively evaluate, through simulation on real-world data, a strategy that integrates AI-CMS into a standard screening scenario to reduce the radiologists' *** total of 89176 consecutive screening exams from the 2023-2024 Reggio Emilia Breast Screening Program (REBSP) were retrospectively considered, which included 479 biopsy-proven cancers (interval cancers were only partially available, therefore false negatives beyond those detected in the real screening workflow could not be assessed). In the proposed strategy, computer-aided detection (CAD) acts as a reader (CR), recalling women with an AI-CMS greater than a predefined threshold (ranging from 5 to 25%). If the first radiologist (HR1) disagrees with CR, the case goes to a second radiologist (HR2) and, in case of human disagreement, to a third radiologist (HR3). For each threshold, final recall rate (RR), cancer detection rate (CDR), number of detected cancers (DC), predictive positive value (PPV) of recalls, false positive rate (FPR), human reading workload, and economic impact were *** AI-CMS thresholds of 5%, 8%, 10%, 15%, 20%, and 25%, human workload decrease ranged from 13.4% to 36.1%. The final RR decreased between 4.3% and 4.0%, slightly lower than the current 4.4% with human double reading. The PPV ranged from 12.6% to 13.3%, higher than the current PPV of 12.2%. The FPR ranged from 3.8% to 3.5%, down from the current 3.9%. With thresholds up to 5%, no true positive cases were missed, maintaining the CDR of 5.4 parts per thousand of those detected by current double reading. Considering CAD payback periods of either 6 or 8 years, financial savings from our strategy ranged from approximately 17800 to over 590,000.ConclusionIntegrating AI-CMS support into a standard screening scenario could substantially reduce the

关键词： femoroacetabular impingement syndrome   total hip replacement   outcome   register   risk factor  

摘要： Purpose Patients with femoroacetabular impingement syndrome (FAIS) may experience persistent hip problems following arthroscopic surgery, with some patients requiring total hip arthroplasty (THA). Therefore, the purpose was (1) to investigate the proportion of THA conversion in a large national Danish cohort of patients with FAIS who had previously undergone hip arthroscopy. (2) To investigate factors that might affect time to conversion. (3) To describe patient-reported outcomes after THA. Methods Patients aged 18 years or above registered with arthroscopic surgery for FAIS between January 2012 and November 2023 in the Danish Hip Arthroscopy Registry (DHAR). Eligible patients were invited to participate in an online survey. If they responded 'yes' to the entry question 'Have you had total hip arthroplasty?', they were asked to complete the Copenhagen Hip and Groin Outcome Score (HAGOS), the Hip Osteoarthritis Outcome Score (0-100 scores, 100 being no problems), the Hip Specific Sports Scale, and Patient Acceptable Symptom State. To perform survival analysis, a Kaplan-Meier method was used to estimate cumulative all-cause conversion to THA. A Cox regression model was fitted after examining proportional-hazards assumptions to examine predictor variables on conversion to THA. Results A total of 5109 patients were eligible and invited for the survey. Of which, 2383 (46.6%) responded;406 patients had received THA at a median of 4.2 [2.1;7.0] years after hip arthroscopy. Regarding HAGOS, patients (N = 199) treated with THA reported mild pain (75 [55;93] points) and problems with daily activities (70 [40;90] points) and moderate problems with sports activities (53 [28;81] points) and hip-related quality of life (50 [30;80] points), 56% participated in sports activities and 62% reported an acceptable symptom state. Conclusions A low number of conversions to THA (8%) was observed. Older age decreased lateral joint space width, T & ouml;nnis grade > 0, higher alpha angle and

关键词： Cervical Cancer   CDK15   Clinicopathological Characteristics   L1CAM   Recurrence and Metastasis  

摘要： Objective: To investigate the association of CDK15(cyclin-dependent kinase 15) and L1CAM L1 (cell adhesion molecule) expression with clinicopathological characteristics and recurrence and/or metastasis after radical hysterectomy of cervical cancer. Methodology: Retrospective analysis was performed on the clinical data of 80 patients with pathologically confirmed cervical cancer who underwent radical hysterectomy at Affiliated Hospital of Hebei University between January 2023 to January 2025. Differences in CDK15 and L1CAM L1 expression in cervical cancer tissues were compared across subgroups stratified by different clinicopathological characteristics, including age and International Federation of Gynecology and Obstetrics(FIGO) stage. Recurrence and metastasis in cervical cancer patients were documented within 12 months post-radical hysterectomy. The Kaplan-Meier method was employed to analyze the association of CDK15/L1CAM expression with recurrence-free survival(RFS). Results: The positive expression rates of CDK15 and L1CAM in cervical cancer tissues were 51.25% and 47.50%, respectively-both significantly higher than the corresponding rates of 22.50% and 18.75% in adjacent non-cancerous tissues(P<0.05). In cervical cancer tissues, the expression of CDK15 exhibited statistically significant differences across subgroups stratified by FIGO stage, histological differentiation, lymph node metastasis, and lymphovascular invasion(P<0.05);whereas the expression of L1CAM demonstrated statistically significant differences across subgroups stratified by FIGO stage, maximum tumor diameter, and lymph node metastasis(P<0.05). Kaplan-Meier analysis revealed that the 12 months RFS rate after radical hysterectomy was approximately 68.29% in cervical cancer patients with positive CDK15 expression, which was lower than the 89.74% in patients with negative CDK15 expression(Log-rank P=0.019). Conclusion: CDK15 and L1CAM are highly expressed in cervical cancer tissues. Consequently,

关键词： Hepatocellular carcinoma   CAD   macrophage   dihydroorotic acid   UBE4B   metastasis  

摘要： Background and Aims:Portal vein tumor thrombosis (PVTT), an indicator of clinical metastasis, significantly shortens hepatocellular carcinoma (HCC) patients' lifespan, and no effective treatment has been established. We aimed to illustrate mechanisms underlying PVTT formation and tumor metastasis, and identified potential targets for clinical intervention. Approach and Results:Multi-omics data of 159 HCC patients (including 37 cases with PVTT) was analyzed to identify contributors to PVTT formation and tumor metastasis. In vitro and in vivo experiments were performed to confirm the critical role of carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase (CAD) in HCC metastasis. Metabolomics and transcriptomics techniques, single-cell RNA sequencing, combined with experimental verification were complemented to illustrate mechanisms underlying CAD induced pro-metastatic efficacy. Analysis of proteogenomic data of HCC cohort identified CAD as the key contributor to PVTT formation and tumor metastasis in HCC. Further experiments confirmed that high CAD expression could significantly promote HCC metastasis, and vice versa. Mechanistically, CAD manipulated de novo pyrimidine anabolism, leading to dihydroorotic acid (DHO) accumulation which directly bound to ubiquitination factor E4B (UBE4B). UBE4B subsequently regulated JAK1 ubiquitination and activated the NF-kappa B pathway to promote epithelial-mesenchymal transition (EMT) of HCC cells. Additionally, CAD generated an immunosuppressive milieu conducive to HCC metastasis by recruiting and reprogramming macrophages into a "pro-tumor" phenotype. Consequently, the metastatic capability of HCC was remarkably enhanced. Conclusion:Therapy targeting CAD may offer a promising approach to curb HCC metastasis by reducing tumor cells' metastatic potential and also shifting the tumor microenvironment towards a less pro-metastatic state.

摘要： Hip morphology has emerged as an important factor in the development of hip osteoarthritis (OA). Cam morphology is one of the most common hip morphologies, characterized by a bony prominence around the femoral head-neck junction of the hip that alters the normal shape of the femoral head. Cam morphology can contribute to intra-articular joint damage by generating abnormal contact stresses at this junction, initiating femoroacetabular impingement (FAI) syndrome and eventually leading to hip OA. Cam morphology is a causal risk factor for hip OA, but not everybody with this morphology will develop FAI syndrome or OA. The pathogenesis of hip disease is probably driven by the interplay between cam morphology, other coexisting hip morphologies (such as pincer morphology), femoral version, spinopelvic parameters and biomechanical and environmental factors. Early identification of FAI syndrome could enable timely, multidisciplinary intervention and offers the potential to modify the trajectory of disease. Cam morphology can develop during skeletal maturation, particularly in adolescents participating in high-joint-load physical activity, raising important questions about preventative approaches. Management of FAI syndrome includes both surgical and non-surgical approaches. Emerging insights into the pathogenesis and detection of cam morphology are paving the way for more targeted interventions and a deeper understanding of its role in FAI syndrome and hip OA development.

关键词： Cams   Nonvolatile memory   Magnetic tunneling   Switches   Sensors   Numerical models   Error analysis   Voltage   Topology   Resistance   Content-addressable memory   ternary CAM   CAM   precharge-free   MRAM   MTJ   DMTJ  

摘要： Content-addressable memories (CAMs) are a class of associative memories known for their capability to perform massively parallel comparisons between an input query pattern and the entire memory content. In the past decade, the increasing demand for high-performance and energy-efficient computing systems has generated significant interest in non-volatile CAMs (NV-CAMs) based on emerging non-volatile memory devices. In this work, we propose a novel non-volatile, precharge-free CAM (NV-PCAM) scheme based on double-barrier magnetic tunnel junctions (DMTJs). When compared to its counterparts, NV-PCAM presents competitive figures of merit in terms of area, speed, and energy efficiency, while also ensuring low search error rates. We also provide a complete class of voltage-divider-based NV-CAM cells for benchmark comparison. All schemes are designed and laid out using a 65 nm process and evaluated under Monte Carlo and process-voltage-temperature (PVT) simulations. Through Monte Carlo simulations, the proposed NV-PCAM demonstrates up to 81% and 85% lower search energy than NV-NOR and NV-NAND, respectively, as well as a 61% and 16% improvement in terms of search delay with a compact cell area footprint.

关键词： Solid modeling   Predictive models   Transformers   Software   Computational modeling   Mathematical models   Three-dimensional displays   Large language models   Image edge detection   Geometry   CAD sketch   detection transformer   geometric primitive   hierarchical graph construction   intermediate outputs  

摘要： Computer-Aided Design (CAD) sketches, composed of geometric primitives and constraints, are fundamental to CAD models and play a critical role in industrial design and manufacturing. Leveraging artificial intelligence to convert hand-drawn sketches and rendered images into CAD sketches has the potential to streamline and accelerate the design process. Existing approaches predominantly focus on separately learning primitives and constraints, often employing two-stage methods or learnable tokens to model these elements independently. However, such methods fail to fully exploit the intrinsic relationships between primitives and constraints. In this paper, we propose LuBan, a lightweight, end-to-end model for CAD sketch generation that eliminates the need for separate constraint models or tokens. LuBan leverages the DEtection TRansformer (DETR) architecture for primitive modeling and distinguishes between parametric and non-parametric features. By deriving sub-primitive features from the intermediate outputs of the primitive model, LuBan facilitates constraint prediction, effectively capturing the inherent relationships between primitives and constraints. This enables the generation of CAD sketches as hierarchical graphs. Qualitative and quantitative experiments on both precise and hand-drawn renderings demonstrate that LuBan achieves state-of-the-art performance. Ablation studies further confirm its superiority over independently trained primitive models, validating its effectiveness. Additionally, LuBan embodies the principle of "what you draw is what you get," offering significant enhancements to the design process for designers.