Search Results (1,940)

Due to its unique benefits over conventional subtractive manufacturing, additive manufacturing methods continue to attract interest in both academia and industry. One such method is called Cold Spray Additive Manufacturing (CSAM), a solid-state coating deposition technology to manufacture repair metallic components using a gas jet and powder particles. CSAM offers low heat input, stable phases, suitability for heat-sensitive substrates, and high deposition rates. However, persistent challenges include porosity control, geometric accuracy near edges and concavities, anisotropy, and cost sensitivities linked to gas selection and nozzle wear. Interdisciplinary research across manufacturing science, materials characterisation, robotics, control, artificial intelligence (AI), and machine learning (ML) is deployed to overcome these issues. ML supports quality prediction, inverse parameter design, in situ monitoring, and surrogate models that couple process physics with data. To demonstrate the impact of AI and ML on CSAM, this study presents a systematic literature review to identify, evaluate, and analyse published studies in this domain. The most relevant studies in the literature are analysed using keyword co-occurrence and clustering. Four themes were identified: design for CSAM, material analytics, real-time monitoring and defect analytics, and deposition and AI-enabled optimisation. Based on this synthesis, core challenges are identified as small and varied datasets, transfer and identifiability limits, and fragmented sensing. Main opportunities are outlined as physics-based surrogates, active learning, uncertainty-aware inversion, and cloud-edge control for reliable and adaptable ML use in CSAM. By systematically mapping the current landscape, this work provides a critical roadmap for researchers to target the most significant challenges and opportunities in applying AI/ML to industrialise CSAM. Full article

(1) Background: There has been an increase in the utilization of the minimally invasive vertical right axillary thoracotomy approach for repairing congenital heart defects in children recently. We aim, in the current study, to evaluate the outcomes of this approach in repairing anomalous pulmonary venous connections with or without an associated sinus venosus defect. (2) Methods: A total of 23 consecutive patients underwent surgical repair of anomalous pulmonary venous connections between April 2018 and February 2024. Perioperative and clinical follow-up data were obtained. (3) Results: The median age and weight were 36 months (1–277 months) and 14.4 kg (3.6–79.4 kg), respectively. More than half were females (13; 56.5%). There was no conversion to sternotomy. Partial anomalous pulmonary venous connections were the most frequent primary diagnoses (14; 60.9%), followed by scimitar syndrome (3; 13%), while two patients (8.7%) had total anomalous pulmonary venous connections. Repair techniques included single patch in 10 patients (43.5%), Warden in 6 (26.1%), and two-patch technique in 4 (17.4%). The median cardiopulmonary bypass and aortic cross-clamp times were 91 and 62 min, respectively. All patients were extubated in the operating room. The median length of hospital stay was 2 days. There were no mortalities or reoperations for pulmonary/systemic venous pathway obstruction. (4) Conclusions: Vertical right axillary thoracotomy is a valuable approach for repairing anomalous pulmonary venous connections with or without sinus venosus defects. All repair techniques, including Warden and scimitar, can be performed safely through this approach. The cosmetic superiority and short hospital stay make this approach worth considering. Full article

Pipelines are critical infrastructure for energy transportation, but long-term service under complex loading can cause local buckling failures. This study investigates the wrinkle behavior of API-X80 pipelines under combined internal pressure and bending using finite element analysis. The results show that increasing internal pressure significantly improves structural stability and delays wrinkle formation by suppressing cross-sectional ovalization. Wrinkle growth and protrusion height were quantified under various geometric and load conditions. Furthermore, a convex B-type sleeve repair method was modeled and optimized using response surface methodology and genetic algorithms. The optimized sleeve design effectively mitigates stress concentration around the defect area. This work provides a theoretical foundation for understanding wrinkle mechanisms and enhancing pipeline integrity under complex loads. Full article

Genomic studies have provided key insights into the molecular pathogenesis of differentiated thyroid carcinoma (DTC), including the role of genes involved in the homologous recombination (HR) related to DNA repair and genomic stability. This research aimed to investigate the genetic landscape of HR genes in thyroid pathology, associated with recurrence risk and clinical prognosis. The study involved six individuals with thyroid conditions, including two patients diagnosed with papillary thyroid carcinoma (PTC) and four individuals with benign thyroid disease. The research material consisted of tumor samples collected during surgical procedures. Protein interactions were analyzed using the STRING database (string-db.org). Homologous recombination genes were sequenced using the HRR Panel vr1.0 on the MiSeq™ Sequencing System. Bioinformatics analysis revealed a relationship between BRAF mutations and HR gene defects in PTC. Mutations in BRCA1, BRCA2, and FANCA genes, typically associated with thyroid tumors, were identified in the tissue of papillary thyroid cancer (PTC). A statistically significant correlation was found between the FANCA gene mutation (rs7195066) and the recurrent course of the PTC. The preliminary findings suggest a potential role for non-pathogenic BARD1 mutations in follicular adenoma. No significant association was found between genes involved in homologous recombination repair and the incidence of papillary thyroid carcinoma, suggesting that these genes may not play a major role in the development of this type of thyroid cancer. Full article

This in vitro study evaluated the fracture resistance of metal–ceramic crowns repaired with milled hybrid resin, printed hybrid resin, lithium disilicate, and direct composite resin. One hundred crowns were fabricated, fractured under controlled loading, and 80 with standardized defects were randomly assigned to four groups (n = 20). Repairs were performed using CAD/CAM onlays or direct composite, followed by compressive testing until fracture. Mean fracture resistance values ranged from 1858.95 N to 1997 N across all groups, exceeding typical posterior occlusal forces (700–900 N). No statistically significant differences were found among groups (p = 0.200). Most failures were cohesive. These results indicate that both digital (milled and printed) and direct techniques offer sufficient strength to serve as minimally invasive and cost-effective alternatives to full crown replacement. Although limited by the in vitro design, this study supports the applicability of modern repair approaches in daily practice. Full article

Arrhythmias significantly contribute to morbidity and mortality in patients with congenital heart disease (CHD). While postoperative factors predisposing to arrhythmias are well-established, early electrophysiological alterations in pediatric CHD remain poorly understood. This review summarizes current knowledge on postnatal cardiac maturation, conduction-system development, and electrophysiological abnormalities in pediatric patients with and without CHD. Importantly, arrhythmia prevalence, mechanisms, and clinical relevance are systematically discussed across three pediatric groups, including healthy children and patients with unrepaired and repaired CHD. Understanding developmental arrhythmogenic mechanisms may facilitate early risk stratification, guide clinical management decisions, and improve long-term outcomes for pediatric patients with CHD. This review discusses the complex interplay between cardiac maturation, congenital defects, and arrhythmogenesis. It also outlines future directions that include noninvasive monitoring, selective intraoperative mapping, animal model studies, and standardized data collection to improve early risk stratification and long-term outcomes in children with CHD. Full article

Allogeneic chondrocyte therapies present an attractive alternative to existing autologous therapies for the repair of cartilage defects, enabling the selection of optimal donor cells and streamlined manufacturing processes. This study investigates the potential of juvenile chondrocytes derived from human infantile (aged 0–4 y) polydactyly digits and the iliac apophysis for cartilage repair using Good Manufacturing Practice bioreactor expansion. Iliac apophysis (n = 4) and polydactyly tissues (n = 4) were assessed histologically. Chondrocytes were isolated enzymatically and cultured using standard tissue culture plastic (TCP) methodology. Upon sufficient cell expansion, chondrocytes were seeded into the Quantum^® bioreactor system or onto TCP (±vitronectin coating). The manufactured chondrocytes growth rates, total cell yields, chondrogenic pellet forming capacity (GAG/DNA, histology), immunoprofiles (flow cytometry) and gene expression (RT-qPCR) were assessed. Equivalent chondrocyte numbers were isolated from polydactyly and iliac apophysis donors per wet weight of tissue. Quantum^®-expanded chondrocytes from both sources yielded comparable cell numbers; however, growth was slowed in the Quantum^® compared to TCP. Polydactyly and iliac apophysis-derived chondrocytes expressed chondrocyte cell surface markers (CD166, CD44, CD151, SOX9) and formed chondrogenic pellets. Quantum^® bioreactor expansion did not alter, gene expression or capacity to form glycosaminoglycans (GAGs (normalised to DNA content)) compared to matched TCP expansion. Juvenile cartilage donors are a promising chondrocyte source for the development of an allogeneic therapy. This novel study expanding juvenile chondrocytes in the Quantum^® GMP-compliant bioreactor suggests that culture conditions may need modification to improve growth, whilst retaining cartilage forming capacity. Full article

Shilajit, a natural herbo-mineral compound with potent antioxidant, anti-inflammatory, and osteogenic properties, has been traditionally used to promote tissue repair. However, limited experimental data exist on its localized application in bone regeneration. This study aimed to evaluate the combined effect of Shilajit and bovine-derived xenograft on bone healing in a rat tibial defect model. Twenty-eight male Sprague–Dawley rats were randomly assigned to four groups (n = 7): Control (defect left to heal spontaneously), Graft-only, Graft + Shilajit 150 mg/kg, and Graft + Shilajit 250 mg/kg. Standardized 3 mm tibial defects were created and filled with xenograft in all groups except the Control. Shilajit was administered intraperitoneally on days 0–3 postoperatively. After 4 weeks, serum total oxidant status (TOS), total antioxidant status (TAS), and TNF-α levels were measured. Tibial specimens underwent histopathological, histomorphometric, and TNF-α immunohistochemical analysis. High-dose Shilajit significantly increased TAS and reduced TOS compared with the Control and Graft-only groups (p < 0.001). Median TNF-α concentrations decreased in a dose-dependent manner, with the lowest values in the high-dose group (15.7 [14.3–17.1] pg/mL, p < 0.001). Histomorphometry revealed the highest new bone area percentage (78.1% [74.9–81.2]) and lowest fibrous tissue content (9.8% [8.1–11.6]) in the high-dose group. Immunohistochemistry confirmed marked suppression of TNF-α expression in Shilajit-treated groups, particularly at high doses. The combination of Shilajit and bovine-derived xenograft significantly enhanced bone regeneration in a dose-dependent manner, likely through antioxidative, anti-inflammatory, and osteogenic mechanisms. These findings suggest that Shilajit may serve as a promising adjunct in bone grafting procedures. Full article

Articular cartilage (AC) is a specialised connective tissue covering joint surfaces. It enables smooth movement, distributes mechanical loads, and protects the underlying bone. In response to loading, AC adapts by modifying both its thickness and composition. AC is organised in different zones, with low cellularity and a high abundance of extracellular matrix (ECM). Mechanical overloading or immobilisation can lead to structural changes, potentially resulting in osteoarthritis (OA), for which no causal treatment currently exists. However, smaller defects can be treated using chondrocyte/cartilage transplantation or tissue engineering. A better understanding of the molecular composition of AC at different locations is essential to improve such therapeutic approaches. For this purpose, we performed a comprehensive analysis of porcine femoral knee cartilage at eight defined anatomical sites. Cartilage thickness and proteoglycan (PG) content were analysed histologically, while specific ECM proteins were assessed by proteomics and validated by immunohistochemistry and Western blot. Significant differences were identified, particularly between medial and lateral compartments, in terms of cartilage thickness, PG abundance, and ECM composition. Some proteins also showed zone-specific localisation patterns. These structural differences likely reflect adaptation to mechanical loading and should be considered to optimise future cartilage repair and tissue engineering strategies. Full article

Complex surgical wounds often necessitate repeated irrigation and debridement (I&D), resulting in substantial burdens. Purified native collagen extracellular matrix plus polyhexamethylene biguanide (PCMP) is a protective antimicrobial barrier that supports innate wound healing and was hypothesized to protect an in vivo complex wound. Canines underwent bilateral fibular defects, which were stabilized using screws and plates pre-incubated with methicillin-resistant Staphylococcus aureus. Wounds were clinically infected seven days post-op and underwent I&D prior to application with either PCMP or non-adherent pads. Outcome assessments included radiography, wound scoring, microbial culture, histology, and gene expression. PCMP application resulted in significantly improved clinical wound healing scores at days 3 and 7, while histological analysis trended towards improved wound repair. Radiological assessments showed no loosening, confirming implant stability. Quantitative microbial assessments showed a minor reduction in bacterial load (0.5 log fold-change) on day 10. Gene expression analysis showed significant upregulation of matrix metalloproteinases and immune-modulating cytokines. Protection of the wound with PCMP resulted in improved wound scores, reduced bacterial load, and significant upregulation in key gene expression pathways compared to controls. Overall, this study suggests that PCMP effectively limited bioburden and biofilm reformation and supported wound progression in a challenging environment. These findings suggest PCMP could enhance complex wound patient outcomes. Full article

Background and Clinical Significance: Atrial septal defects (ASDs), particularly the ostium secundum type, are congenital cardiac anomalies that can lead to serious complications if left untreated. Percutaneous closure using devices like the Amplatzer Septal Occluder (ASO) has become a widely accepted approach, although complications such as device embolization can occur. Case Presentation: We present a unique case of a 28-year-old woman who developed acute hemodynamic instability and arrhythmias following embolization of an Amplatzer device into the right ventricle during an ASD closure. Despite initial treatment with antiarrhythmic medication, the patient required urgent open-heart surgery for device retrieval and ASD closure. The surgery successfully involved pericardial patch closure of the ASD, device removal from the right ventricle, and the performance of the Kay procedure to address significant tricuspid regurgitation. Postoperative recovery was uneventful, with the patient stabilized and discharged in stable condition. Conclusions: This case highlights the critical need for rapid surgical intervention in cases of device embolization, and the importance of multidisciplinary coordination in managing such complex complications. The combination of ASD closure, device retrieval, and tricuspid valve repair led to a successful outcome, underscoring the importance of timely, decisive action in complex cardiovascular emergencies. Full article

Transparent polymer sheaths are often utilized in neuroendoscopic procedures to minimize intraventricular bleeding and parenchymal injuries. However, cerebrospinal fluid (CSF) leakage remains a common complication following neuroendoscopic surgery for intraventricular and deep-seated lesions. We investigated an innovative technique to prevent postoperative CSF leakage through the tract using a collagen matrix dural graft. A rolled collagen matrix (DuraGen^®) was used as a parenchymal tract tamponade to seal the tract created by an angiocatheter (preclinical pilot) or neuroendoscopic sheath (clinical case studies). A small pilot study using a juvenile pig model was first conducted to test the implantation technique and to evaluate the inflammatory response to, and absorption of intraparenchymal DuraGen. The efficacy of this approach was then assessed in two clinical cases using MRI at postoperative days 1, 7, 40, and 60. The outer segment of the graft was unfurled to cover the dural defect for clinical application. In the pig model, histological analysis showed healing with minimal inflammation in DuraGen^®-implanted hemispheres, while untreated control tracts exhibited parenchymal scarring and chronic inflammation. In both patients, postoperative MRI demonstrated resolution of subdural fluid collections and progressive absorption of DuraGen^® with no complications. This technique ameliorated CSF leakage and enhanced parenchymal healing after neuroendoscopic surgery. DuraGen^® may modulate the local environment for tissue repair beyond its use in dural grafting. Full article

Mass customisation in the automotive industry has exploded the number of wiring harness variants that must be assembled, tested and repaired on the shop floor. Existing CAD or schematic formats are too heavy and too coarse-grained to drive in-line, per-VIN validation, while supplier documentation is heterogeneous and often incomplete. This paper presents a pin-centric, two-tier graph model that converts raw harness tables into a machine-readable, wiring-aware digital twin suitable for real-time use in manufacturing plants. All physical and logical artefacts—pins, wires, connections, paths and circuits—are represented as nodes, and a dual-store persistence strategy separates attribute-rich JSON documents from a lightweight NetworkX property graph. The architecture supports dozens of vehicle models and engineering releases without duplicating data, and a decentralised validation pipeline enforces both object-level and contextual rules, reducing initial domain violations from eight to zero and eliminating fifty-two circuit errors in three iterations. The resulting platform graph is generated in 0.7 s and delivers 100% path-finding accuracy. Deployed at Ford’s Almussafes plant, the model already underpins launch-phase workload mitigation, interactive visualisation and early design error detection. Although currently implemented in Python 3.11 and lacking quantified production KPIs, the approach establishes a vendor-agnostic data standard and lays the groundwork for self-aware manufacturing: future work will embed real-time validators on the line, stream defect events back into the graph and couple the wiring layer with IoT frameworks for autonomous repair and optimisation. Full article

The keyhole defect located at the termination of the friction stir welding (FSW) seam of 6082 aluminum alloys was repaired utilizing the refilling friction stir spot technique. This study examined the impact of the plunge depths on the microstructure of the welding spot. The results show that under the action of shear stress introduced by the pin, the (111)[1$\overline{1}$0] shear texture and (112)[11$\overline{1}$] Copper texture were formed. The formation of (001)[100] Cube and (001)[310] Cube_ND textures was due to the occurrence of discontinuous dynamic recrystallization. When the plunge depth of the sleeve was 1.0 mm, the volume fraction of deformed grains in the welding spot reached 45%, and the tensile strength of the welding spots was 184 MPa. When the plunge depth of the sleeve was 1.5 mm, the tensile strength of the repaired spot welding was 210 MPa, which was basically equal to the strength of the FSW seam. Full article

Background: Skin injuries, such as chronic wounds and inflammatory skin diseases, often face limitations in treatment efficacy due to the low efficiency of transdermal drug delivery and insufficient local concentrations. Curcumin (CUR), a natural compound with anti-inflammatory and antioxidant properties, has demonstrated potential in the repair of skin damage; however, its clinical application is hindered by its physicochemical characteristics. This study constructs a novel nanocomposite drug delivery system: CUR-loaded micellar nanocomposite gel (CUR-M-DMNs-Gel). A composite system is used to achieve the efficient solubilization and enhanced transdermal permeation of CUR, thereby providing a novel formulation approach for the treatment of skin diseases. Methods: CUR-loaded micellar (CUR-M) utilizes CUR as the core active ingredient, which possesses multiple pharmacological effects including anti-inflammatory and antioxidant properties. TPGS serves as a micellar carrier that not only enhances the solubility and stability of CUR through its amphiphilic structure but also facilitates drug absorption and transport within the body. In dissolvable microneedles (DMNs), PVP K30 forms a stable three-dimensional network structure through entanglement of polymer chains, ensuring sufficient mechanical strength for effective penetration of the skin barrier. Meanwhile, PVP K90, with its higher molecular weight, enhances the backing’s support and toughness to prevent needle breakage during application. The incorporation of hyaluronic acid (HA) improves both the moisture retention and adhesion properties at the needle tips, ensuring gradual dissolution and release of loaded CUR-M within the skin. In CUR-loaded micellar gel (CUR-M-Gel), PVP K30 increases both adhesive and cohesive forces in the gel through chain entanglement and hydrogen-bonding interactions. Tartaric acid precisely regulates pH levels to adjust crosslinking density; glycerol provides a long-lasting moisturizing environment for the gel; aluminum chloride enhances mechanical stability and controlled drug-release capabilities; NP-700 optimizes dispersion characteristics and compatibility within the system. Results: In vitro experiments demonstrated that the CUR-M-DMNs-Gel composite system exhibited enhanced transdermal penetration, with a cumulative transdermal efficiency significantly surpassing that of single-component formulations. In the mouse skin defect model, CUR-M-DMNs-Gel facilitated collagen deposition and effectively inhibited the expression of inflammatory cytokines (TNF-α, IL-6, and IL-1β). In the mouse skin photoaging model, CUR-M-DMNs-Gel markedly reduced dermal thickness, alleviated damage to elastic fibers, and suppressed inflammatory responses. Conclusions: The CUR-M-DMNs-Gel system can enhance wound healing through subcutaneous localization, achieving long-term sustained efficacy. This innovative approach offers new insights into the treatment of skin injuries. Full article