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关键词： Robotic disassembly   Cross-modal deep learning   Large language models   Semantic graph   Spatial constraint modelling   Remanufacturing  

摘要：

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  Fuse LLMs and cross-modal deep learning for spatial disassembly constraint modelling.
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  Derive comparable multimodal cues using identical feature extraction mechanisms.
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  Align CAD models with captured images via LLM-assisted semantic graph reasoning.
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  Leverage LLMs to clarify similar components for precise spatial constraint retrieval.
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  Enable automatic and flexible removal of used bolster springs using robotic systems.

关键词： Missing part retrieval   Graph neural networks   CAD assembly   Contrastive learning   Assembly graphs   Geometric deep learning  

摘要：

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  SLOT-GNN retrieves a missing CAD part from a large candidate library.
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  Masked-node retrieval: the unknown part is a learnable slot in the assembly graph.
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  Edge-conditioned message passing over mate type and MCF transform features.
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  Missing Part-Retrieval Benchmark: 234,299 parts, 42,206 assemblies, 255k slots.
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  Correct part at median rank 5 out of 234,299 candidates, +35% over baselines.

关键词： Modeling   Federated learning   Cams   Computer aided manufacturing   Conferences   Computers   Accuracy   Computer vision   Distance measurement   Covariance matrices   Federated distillation   proxy data   knowledge transfer   CAM   mahalanobis distance  

摘要： Although federated learning solves the problems of traditional data silos and personal data privacy, it still faces the challenges of model and data heterogeneity. Instead of sharing model parameters, the introduction of knowledge distillation in federated learning enables knowledge sharing among heterogeneous clients. However, most existing distillation rely on proxy data, ignoring the issue of misleading knowledge sharing that comes with proxy data. Especially when there are domain offsets in local data, it poses the challenge for inter-domain generalization performance. To address this, a new Federated distillation method (FedCAMD) based on the CAM combined with the Mahalanobis Distance is proposed. This constructs the similarity between proxy data and local data via the CAM, then identifies outlier proxy data by combining it with the improved Mahalanobis Distance, effectively avoiding the sharing of misleading knowledge. In addition, our method primarily models proxy data and local data and thus can be integrated into any federated distillation method that uses proxy data for knowledge transfer. Extensive experiments on various cross-domain datasets (including local cross-domain datasets: Digits, Office Caltech, Office31, Office-Home and PACS;proxy datasets: Cifar-100 and Fashion-MNIST) to validate the proposed method, all of which show that our method significantly enhances the model's inter-domain generalization performance. Furthermore, we provide ablation experiments to validate the effectiveness of the proposed FedCAMD.

关键词： Hybrid ceramic restorative material   Tooth wear   Treatment outcome  

摘要： Purpose: To evaluate the clinical use of CAD/CAM hybrid ceramics in patients with severe tooth wear. Methods: Forty-nine patients with severe tooth wear underwent prosthetic management with 116 hybrid ceramic restorations. The restorations were evaluated at 1 week and at 3, 6, 12, 18, 24, 30, and 36 months after placement. The amount of wear on the restorations, antagonist teeth, and opposite teeth was compared using digital superimposition analysis. A questionnaire was used to evaluate participants' satisfaction with the restorations. Complications were recorded, and survival rates were estimated using Kaplan-Meier analysis. Results: The clinical performance of the restorations was stable for esthetic, functional, and biological parameters up to 3 years, except for greater changes in "surface and margin staining" and "fracture and retention." There was no significant difference in the amount of progressive wear among the restorations, antagonist teeth, and opposite side teeth until 18 months;however, the wear on the restorations increased gradually up to 36 months. Higher scores and identical satisfaction results were obtained for the chewing efficiency and cleanability during the observation period. The most common complications were restoration dislodgement (5.2%) and partial marginal chipping (4.3% which were clinically repaired. Four restorations (3.4%) were extensively fractured and replaced. The estimated survival rate of the hybrid ceramic restorations at 3 years was 88.0%. Conclusions: The clinical use of hybrid ceramic restorations in patients with severe tooth wear improved chewing efficiency and esthetics, provided adequate resistance for load-bearing, and delivered a stable treatment outcome after functional use.

关键词： Aerostructural shape optimization   CAD model   CFD   Continuous adjoint   Deep Neural Networks   Machine learning  

摘要： This article presents a gradient-based shape optimization workflow for the aerodynamic and aerostructural design of a civil aircraft, by focusing on the use of machine learning models to replace CAD-related blocks in this workflow. To this end, a Deep Neural Network (DNN), in the form of a two-branch $\lambda$-DNN, replaces the CAD-based parameterization of the aircraft wing shape. The $\lambda$-DNN is trained on a set of snapshots (point clouds) of the aircraft surface for various design variable sets. It reconstructs the wing surface, without having access to the corresponding CAD model. During the optimization, inputs to the $\lambda$-DNN are the nodal coordinates of the baseline geometry and the design vector of each new geometry. The derivatives of surface coordinates with respect to the CAD parameters are computed by differentiating the $\lambda$-DNN. A study that demonstrates the superiority of the $\lambda$-DNN over a standard fully connected neural network is presented. The proposed workflow is used in the aerodynamic and aerostructural optimization of the high aspect ratio wing of the DLR-F25 transport aircraft model. The optimizations target minimum drag, subject to lift and pitching moment constraints. For the aerostructural optimization, thousands of structural constraints are also imposed, by embedding the structural sizing into an aeroelastic optimization loop. The obtained reduction in aircraft’s drag results in significant fuel saving for a typical mission, overall proving that the used $\lambda$-DNN can safely replace the necessary CAD model operations.

摘要： Carbamoyl-phosphate synthetase II, aspartate transcarbamylase and dihydroorotase (CAD) is a multifunctional, rate-limiting enzyme involved in de novo pyrimidine synthesis. Its activity is tightly regulated, primarily through phosphorylation and allosteric mechanisms. However, the contribution of other post-translational modifications to CAD regulation remains largely unexplored. Here we identify ubiquitination as a novel regulatory mechanism controlling CAD stability. We show that CAD undergoes K29-linked ubiquitination and proteasomal degradation following ubiquitination at lysine residues K1325 and K1411 within its carbamoyl-phosphate synthetase II (CPS II) domain. Inhibiting CAD ubiquitination by mutating these lysine sites promotes its stability, de novo pyrimidine synthesis and tumor growth. Notably, CAD protein expression is elevated in cervical cancer and is associated with poor prognosis. Furthermore, we identify OTU domain-containing protein 6 A (OTUD6A) as a deubiquitylase that directly interacts with the CPS II domain of CAD, leading to its deubiquitylation and stabilization. OTUD6A overexpression enhances de novo pyrimidine synthesis and tumor growth in a CAD-dependent manner. OTUD6A is also upregulated in cervical cancer, positively correlating with CAD protein levels and poor prognosis of cervical cancer patients. Collectively, our results reveal the OTUD6A-CAD axis as a critical regulator of pyrimidine metabolism in cervical cancer, highlighting a potential vulnerability for therapeutic targeting.

关键词： 混维凹凸棒土   姜黄素   机械力化学球磨法   功能改性  

摘要： 针对传统织物改性工艺复杂、溶剂污染大的问题，以混维凹凸棒土（MDA）为载体，经柠檬酸（CA）与二甲基双十八烷基氯化铵（DODMAC）分步改性制备MDA1、MDA2，采用机械力化学球磨法负载姜黄素（Cur）制得MDA2/Cur杂化材料。基于相变涂层PTL-pSBMA-ε-PL(PPL)的原位聚合将MDA2/Cur固定于织物表面，制备MDA2/Cur/PPL(MCPPL)改性功能化织物。通过单因素及正交试验优化负载工艺，确定最优参数：球磨30 min，转速200 r/min、MDA2与Cur质量比1.5∶1。MCPPL可在涤纶、纯棉、丝绸表面形成均匀致密涂层，改性丝绸紫外线防护系数（UPF）达807，防紫外线效果优异。本研究为混维凹凸棒土高值化利用及绿色功能纺织品研发提供了新途径。

关键词： Cadmium   Selenium   Heavy metal stress   Lignification   Transcriptional regulation   BHLH39  

摘要： Cadmium (Cd), a highly toxic heavy metal, poses significant threats to agricultural productivity and human health by accumulating in the food chain. Selenium (Se), an essential micronutrient, has shown promise in mitigating Cd toxicity in plants. However, the underlying molecular mechanisms remain largely unknown. This study elucidates how exogenous selenite (Na₂SeO₃) reduces Cd accumulation in the edible parts of flowering Chinese cabbage. Our results demonstrate that Se application (2.5 µM) dramatically mitigated Cd-induced growth inhibition, recovering shoot and root biomass to 96.3% and 90.7% of those of the control levels, respectively, while significantly decreasing Cd concentration in the shoots. Mechanistically, Se orchestrates a multi-layered defense strategy in the roots under Cd stress. Ultrastructural and physiological analyses revealed that, Se reduced the average net Cd^2 + influx by 24.3%, increased root cell wall thickness by 40%, and significantly boosted cell wall lignification under Cd stress. Furthermore, Se promoted Cd compartmentalization by shifting Cd from metabolically sensitive organelles to the soluble fraction under Cd stress. At the molecular level, transcriptome analysis combined with Weighted Gene Co-expression Network Analysis (WGCNA) identified a potential regulatory module. The transcription factor bHLH39 acts as a key repressor, directly binding to the promoter of the lignin biosynthesis gene CAD5. Se co-application suppresses the Cd-induced expression of bHLH39, thereby de-repressing CAD5 expression to promote lignification and physically restrict Cd translocation. This study identified the bHLH39-CAD5 regulatory module as a potential mechanism underlying Se-mediated Cd detoxification, providing a strategy for improving low-Cd leafy vegetables crops to ensure food safety.

关键词： Vascular smooth muscle cells   CAD   Pyrimidine biosynthesis   Ribosome biogenesis   Vascular disease  

摘要：

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  CAD is upregulated in Ang-II-treated VSMCs and ligation-induced neointimal lesions.
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  Silencing CAD inhibits Ang-II-induced VSMC proliferation and migration.
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  CAD promotes ICAM-1 and MMP-9 translation via rRNA synthesis.
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  Targeting CAD mitigates neointima formation in occlusive vascular disease.