Search Results (888)

Background: Abdominal wall endometriosis (AWE) is a rare pathological condition that mostly occurs in the post-cesarean section. This study aimed to describe the surgical approach employed in treating 31 patients at our center over the past decade and compare the outcomes with those reported in scientific literature. Methods: We retrospectively evaluated the data of 31 patients with a cesarean section history who underwent surgery for AWE excision between 1 November 2012, and 31 January 2023, at the University of Naples Federico II, Italy. Subsequently, we reviewed the scientific literature for all AWE-related studies published between 1 January 1995, and 31 July 2024. Results: Most women presented with a palpable abdominal mass (90.3%) at the previous surgical site associated with cyclic abdominal pain (80.6%) concomitant with menstruation. All patients underwent preoperative abdominal ultrasound and magnetic resonance imaging, 71% underwent computed tomography, and 32.2% received ultrasound-guided needle biopsies. Furthermore, 90.3% and 9.7% had previous Pfannenstiel and median vertical surgical incisions, respectively. All patients underwent laparotomic excision and abdominal wall reconstruction, with prosthetic reinforcement used in 73.5% of cases. No recurrent nodules were detected in any patient at the 12-month follow-up. Conclusions: AWE should be suspected in women with a history of cesarean section presenting with palpable, cyclically painful abdominal mass associated with the menstrual cycle. Preoperative ultrasound and magnetic resonance imaging are essential, and surgical excision must ensure clear margins. Abdominal wall reconstruction should include prosthetic reinforcement, except when the defect is minimal (≤1.5 cm). An ultrasound follow-up at 12 months is recommended to confirm the absence of recurrence. Full article

Laser beam powder bed fusion of metals (PBF-LB/M, or simply L-PBF) has emerged as one of the most competitive additive manufacturing technologies for producing complex metallic components with high precision, design freedom, and minimal material waste. Among the various categories of additive manufacturing processes, L-PBF stands out, paving the way for the execution of part designs with geometries previously considered unfeasible. Despite offering several advantages, parts with overhang features require the use of support structures to provide dimensional stability of the part. Support structures achieve this by resisting residual stresses generated during processing and assisting heat dissipation. Although the scientific community acknowledges the role of support structures in the success of L-PBF manufacturing, they have remained relatively underexplored in the literature. In this context, the present work investigated the impact of laser power and scanning speed on the dimensioning, integrity and tensile strength of single-walled block type support structures manufactured in AISI 316L stainless steel. The method proposed in this work is divided in two stages: processing parameter exploration, and mechanical characterization. The results indicated that support structures become more robust and resistant as laser power increases, and the opposite effect is observed with an increment in scanning speed. In addition, defects were detected at the interfaces between the bulk and support regions, which were crucial for the failure of the tensile test specimens. For a layer thickness corresponding to 0.060 mm, it was verified that the combination of laser power and scanning speed of 150 W and 500 mm/s resulted in the highest tensile resistance while respecting the dimensional deviation requirement. Full article

Infrared thermography is a common approach used in building inspection for identifying building envelope thermal anomalies that cause energy loss and occupant thermal discomfort. Detecting these anomalies is essential to improve the thermal performance of energy-inefficient buildings through energy retrofit design and correspondingly reduce operational energy costs and environmental impacts. A thermal bridge is an unwanted conductive heat transfer. On the other hand, an infiltration/exfiltration anomaly is an uncontrollable convective heat transfer, typically happening around windows and doors, but it can also be due to a defect that comprises a building envelope’s integrity. While the existing literature underscores the significance of automatic thermal anomaly identification and offers insights into automated methodologies, there is a notable gap in addressing an automated workflow that leverages building envelope component segmentation for enhanced detection accuracy. Consequently, an automatic thermal anomaly identification workflow from visible and thermal images was developed to test it, utilizing segmented building envelope information compared to a workflow without any semantic segmentation. Therefore, building envelope images (e.g., walls and windows) were segmented based on a U-Net architecture compared to a more conventional semantic segmentation approach. The results were discussed to better understand the importance of the availability of training data and for scaling the workflow. Then, thermal anomaly thresholds for different target domains were detected using probability distributions. Finally, thermal anomaly masks of those domains were computed. This study conducted a comprehensive examination of a campus building in Syracuse, New York, utilizing a drone-based data collection approach. The case study successfully detected diverse thermal anomalies associated with various envelope components. The proposed approach offers the potential for immediate and accurate in situ thermal anomaly detection in building inspections. Full article

Phage therapy shows promise as an adjunct to antibiotics for treating Staphylococcus aureus infections. We previously reported a combined flucloxacillin/two-phage cocktail treatment selected for resistance to podovirus phage 66 in a rodent model of methicillin-susceptible S. aureus (MSSA) endocarditis. Here we show that resistant clones harbor mutations in tarS, which encodes a glycosyltransferase essential for β-GlcNAcylation of wall teichoic acid (WTA). This WTA modification has been described in vitro as critical for podoviruses adsorption. Transcriptomics confirmed continued tarS expression in resistant clones, supporting a loss-of-function mechanism. Accordingly, phage 66 binding and killing were restored by WT tarS complementation. In addition, we investigated the counterintuitive innate susceptibility to phage 66 of the tarM + Laus102 strain used in the endocarditis model. We show that it likely results from a significant lower tarM expression, in contrast to the innate resistant strain RN4220. Our findings demonstrate that tarS-mediated WTA β-GlcNAcylation is critical for podovirus infection also in vivo and identify tarM transcriptional defect as a new mechanism of podoviruses susceptibility in S. aureus. Moreover, and since tarS disruption has been previously shown to enhance β-lactam susceptibility, our results support the development of combined podovirus/antibiotic strategies for the management of MRSA infections. Full article

Objectives: The aim of this study was to determine the differential temperature produced on ceramic implants using laser irradiation on a pulsed setting of intrabony defects in vitro. Methods: A ceramic (Zr) dental implant (Zeramex, 4.8 × 12 mm) was placed into a bovine bone block. A three-wall intrabony defect (6 × 4 × 3 mm) was created to mimic an osseous peri-implant defect. Thermocouples were placed on the apical and coronal areas to measure temperature changes (∆T) during 60 s of laser irradiation. The bovine block was heated to 37 °C, and the defect walls were irradiated with the CO₂ and Er,Cr:YSGG laser. The settings used were pulsed mode for both lasers, with 30 Hz and 1.5 W for the Er,Cr:YSGG laser and 70 Hz and 2 W for the CO₂ laser. The same laser settings were repeated at room temperature (RT, 23 °C). Twenty trials were performed for each experimental group at room and body temperature for assessment of ∆T. Paired t-test were used to compare the measurements between 37 °C and 23 °C for the Er,Cr:YSGG, and CO₂ laser, respectively. Results: The CO₂ laser resulted in the highest ∆T (°C) at the coronal (15.22 ± 0.28/8.82 ± 0.21) and apical (5.84 ± 0.14/2.30 ± 0.28) level when this laser was used in both room temperature and body temperature, respectively. The highest ∆T (°C) for the Er,Cr:YSGG laser at body temperature at the coronal thermocouple was 7.64 ± 0.55, while for the CO₂ laser, at body temperature was 8.82 ± 0.21. Conclusion: Within the limitations of our study, the use of CO₂ laser and Er,Cr:YSGG laser on peri-implant defects generally appears to be safe in treating peri-implant defects around zirconia implants in vitro. Full article

This study characterized collagen remodeling in an electron-beam-sterilized porcine acellular dermal matrix (E-PADM) by evaluating host response kinetics during wound healing. E-PADM (n = 6 lots/time point) was implanted in an abdominal wall bridging defect in nonhuman primates (N = 24). Histological, immunohistochemical, and biochemical assessments were conducted. Pro-inflammatory tissue cytokines peaked 1 month post-implantation and subsided to baseline by 6 months. E-PADM-specific serum immunoglobulin G antibodies increased by 213-fold from baseline at 1 month, then decreased to <10-fold by 6–9 months. The mean percentage tissue area staining positively for matrix metalloproteinase-1 plateaued at 3 months (40.3 ± 16.9%), then subsided by 6 months (16.3 ± 11.1%); tissue inhibitor matrix metalloproteinase-1 content plateaued at 1 month (39.0 ± 14.3%), then subsided by 9 months (13.0 ± 8.8%). Mean E-PADM thickness (1.7 ± 0.2 mm pre-implant) increased at 3 months (2.9 ± 1.5 mm), then decreased by 9 months (1.9 ± 1.1; equivalent to pre-implant). Histology demonstrated mild inflammation between 1–3 months, then a peak in host tissue deposition, with ≈75%–100% E-PADM collagen turnover, and fibroblast infiltration and neovascularization between 3–6 months. Picrosirius red staining revealed that mature E-PADM collagen was replaced by host-associated neo-collagen by 6 months. E-PADM implantation induced wound healing, which drove dermal E-PADM collagen remodeling to native, functional fascia-like tissue at the implant site. Full article

Background: Two-dimensional periapical radiographs (PAs) only offer limited information regarding three-dimensional periodontal infrabony defects. In contrast, cone beam computed tomography (CBCT) enables visualization of the entire defect morphology. This study aimed to evaluate the agreement between CBCT and direct intrasurgical measurements (ISs) regarding the characteristics of infrabony defects, including measurements of defect depth, width, the type of defect (one-wall, two-wall, three-wall), and defect extension. Methods: Intrasurgical and radiographic assessments were performed by two calibrated examiners on 26 infrabony defects in 17 patients who underwent periodontal surgery. The defect depth, width, type, and extension were compared between intrasurgical observations and PA or CBCT findings. The CBCT assessment was performed mainly using axial reconstructions. Angle measurements were compared between CBCT and PAs. Results: The mean differences between CBCT and intrasurgical measurements were −0.11 ± 0.49 mm for depth and −0.07 ± 0.41 mm for width, with no significant differences. The ICC values were 0.938 and 0.923 for depth and width, respectively. The mean difference in width between PAs and ISs was significantly different (−0.36 ± 0.73 mm; p = 0.002). CBCT demonstrated high agreement with intrasurgical observations for defect type (κ = 0.819) and defect extension (κ = 0.855), while lower agreements were found for PAs. Conclusions: CBCT is a valid assessment modality for infrabony defects. It demonstrated strong agreement with ISs—as the gold standard—for depth and width measurements, and its agreement with ISs regarding defect type and extension appeared to surpass that of PAs. Full article

Body stalk anomaly (BSA) is a rare and usually fatal congenital disorder involving severe malformations of the body wall, limbs, spine, and internal organs. This study presents the first documented cases of BSA in seven dogs, offering new insights into how the disorder manifests in animals. The affected fetuses consistently exhibited major anomalies, including large abdominal wall defects, structural spinal abnormalities, and a variety of limb malformations ranging from partial agenesis and meromelia to phocomelia and complete amelia. Structural urogenital anomalies and orofacial clefts were also observed, aligning with similar findings in BSA cases reported in pigs and cats. These findings support the hypothesis of a multifactorial etiology involving early embryonic disruptions, such as abnormal folding of the embryo, rupture of the amniotic membrane, and vascular compromise. The frequent occurrence of abdominal wall defects alongside umbilical cord abnormalities further suggests a shared developmental pathway. This study also highlights the value of veterinary cases in comparative embryology and the need to assess congenital anomalies as part of a broader malformation complex. By expanding the phenotypic spectrum of BSA in domestic animals, this work contributes to a deeper understanding of its pathogenesis and emphasizes the importance of further research into the genetic and environmental factors involved. Such efforts could lead to improved classification and diagnosis of complex congenital malformations, as well as facilitate cross-species comparisons. Full article

This study consisted of the injection molding simulation of polycaprolactone (PCL)-based nanocomposites reinforced with multi-walled carbon nanotubes (MWCNTs) for biomedical implant manufacturing. The simulation was additionally supported by experimental validation. The influence of varying MWCNT concentrations (0.5%, 5%, and 10% by weight) on key injection molding parameters, i.e., melt flow behavior, pressure distribution, temperature profiles, and fiber orientation, was analyzed with SolidWorks Plastics software. The results proved the low CNT content (0.5 wt.%) to be endowed with stable filling times, complete mold cavity filling, and minimal frozen regions. Thus, this formulation produced defect-free modular filament sticks suitable for subsequent 3D printing. In contrast, higher CNT loadings (particularly 10 wt.%) led to longer fill times, incomplete cavity filling, and early solidification due to increased melt viscosity and thermal conductivity. Experimental molding trials with the 0.5 wt.% CNT composites confirmed the simulation findings. Following minor adjustments to processing parameters, high-quality, defect-free sticks were produced. Overall, the PCL/MWCNT composites with 0.5 wt.% nanotube content exhibited optimal injection molding performance and functional properties, supporting their application in modular, patient-specific biomedical 3D printing. Full article

Machining Nomex honeycomb cores is essential for manufacturing components that meet the stringent requirements of industrial sectors, but the complexity of this type of structure material requires specialized techniques to minimize defects, ensure optimal surface quality and extend cutting tool life. For this reason, an innovative machining technology based on longitudinal–torsional ultrasonic vibration assistance has been integrated into a CZ10 combined cutting tool, with the aim of optimizing the efficiency of conventional machining processes. To this end, a three-dimensional numerical model based on the finite element method, developed using Abaqus/Explicit 2017 software, was used to simulate the complex interactions between the cutting tool and the thin walls of the structures to be machined. This study aimed to validate the numerical model through experimental tests, quantifying the surface condition, cutting force and tool wear, while evaluating the impact of key machining parameters, such as feed rate and wall thickness, on process performance. The obtained results reveal a substantial reduction in cutting forces, varying from 20 to 40%, as well as a notable improvement in surface finish and a significant extension of tool life. These conclusions open up new perspectives for the optimization of industrial processes, particularly in high-demand sectors such as aeronautics. Full article

Carbon nanotubes (CNTs) are cylindrical nanostructures formed by rolling a graphene sheet—a hexagonal lattice of carbon atoms—into a tube. Based on the rolling direction, CNTs are categorized as armchair, zigzag, or chiral. The chiral vector, derived from the graphene lattice, defines the CNT’s structure, with chiral CNTs denoted by indices (n, m), where m > 0 and m ≠ n. The mechanical properties and structural stability of CNTs are highly sensitive to defects and impurities within their atomic framework. Among these, point defects such as single-atom vacancies are the most prevalent and can significantly degrade mechanical performance. These defects alter stress distribution, reduce stiffness, and impair strength, thereby limiting the functional reliability of CNTs in advanced applications such as nanocomposites, sensors, and electronic devices. This study examines the influence of vacancy defects on CNT mechanical behavior through a multiscale modeling framework. Molecular dynamics (MD) simulations are conducted using LAMMPS, with structural visualization via Visual Molecular Dynamics (VMD). Concurrently, a finite element (FE) model is developed in ANSYS, where the CNT is idealized as a space frame of elastic beam elements representing carbon–carbon bonds. The integration of atomistic and continuum approaches offers a comprehensive understanding of defect-induced mechanical degradation. The MD and FEM results are in strong agreement with findings in existing literature, validating the adopted methodology. These findings contribute valuable insights into the design and optimization of CNT-based materials for high-performance engineering applications. Full article

Background: Maxillofacial bone defects present considerable challenges in oral and reconstructive surgery. While autologous bone grafts are the gold standard, their limitations, such as donor site morbidity and limited availability, have driven the search for alternative biomaterials. SmartBone^®, a xeno-hybrid graft, offers potential advantages due to its bioactivity and remodeling capacity. Methods: This analysis of a series of clinical cases, evaluated the performance of SmartBone^® in 10 patients presenting with various maxillofacial bone defects. The patient follow-up period spanned from 2017 to 2019, with a maximum duration of 30 months. Bone grafting was performed, and integration was monitored using Cone-Beam Computed Tomography at multiple timepoints. Bone density changes (ΔCT values) in selected anatomical sites were analyzed to assess graft transformation and integration. Results: SmartBone^® supported effective bone regeneration and selective remodeling in all cases. One patient required a revision procedure, after which successful integration was observed. Cellular colonization began within weeks, with complete remodeling into mature bone occurring between 6–12 months. Evidence of cortical wall resorption and reformation on the graft’s external surface confirmed this transformation. ΔCT values progressively aligned with native bone densities, indicating structural and functional integration. Conclusions: SmartBone^® demonstrates strong osteointegrative and site-specific remodeling capabilities, offering a reliable and predictable alternative for maxillofacial bone reconstruction. The study presents several limitations, including the small sample size, inter-patient variability, possible imaging artifacts due to metallic elements in Cone-Beam Computed Tomography scans and the lack of histological confirmation. Full article

Background and Objectives: The isthmocele is a pouch-shaped defect in the anterior uterine wall, site of a previous cesarean section, due to a scar defect or dehiscence. The prevalence could be underestimated, but the rate of cesarean section is still high in the world. The preferable technique to correct this anomaly is not clearly indicated in the literature. Our objective is to evaluate the literature on the surgical treatment of isthmocele in pre-Cesarean women treated with minimally invasive technique. Our hypothesis is that robotic treatment is more effective than other procedures in women desirous of having children. Materials and Methods: The words “isthmocele”, “laparoscopy”, “robot” and “cesarean scar pregnancy” were searched on the main online scientific search sources (PubMed, Google Scholar, Scopus, WES, and Embase, etc.). We included articles in English and French, chosen for the relevance to the topic. We have decided to include also surgical corrections of isthmocele linked to pregnancies at the site of the defect, with particular attention to video training explanation. Results: We analyzed the literature about the minimally invasive surgery for the repair of an isthmocele, evaluating 20 articles. Comparing several surgical techniques, robotic-assisted laparoscopy could be an effective method to correct the defect, without high risk of intraoperative complications. Conclusions: As indicated in the literature, robotic tailored excision and repair of isthmocele (and of concomitant cesarean scar pregnancy) could be advantageous and safe, and it is necessary to promote video-training about this technique. Full article

Traditional narrow gap welding of thick titanium alloy plates easily produces dynamic molten pool flow instability, poor sidewall fusion, and excessive residual stress after welding, which leads to defects such as pores, cracks, and large welding deformations. In view of the above problems, this study takes 16-mm-thick TC4 titanium alloy as the research object, uses low-power pulsed laser-GTA flexible heat source welding technology, and uses the flexible regulation of space between the laser, arc, and wire to promote good fusion of the molten pool and side wall metal. By implementing instant ultrasonic impact treatment on the weld surface, the residual stress of the welded specimen is controlled within a certain range to reduce deformation after welding. The results show that the new welding process makes the joint stable, the side wall is well fused, and there are no defects such as pores and cracks. The weld zone is composed of a large number of α′ martensites interlaced with each other to form a basketweave structure. The tensile fracture of the joint occurs at the base metal. The joint tensile strength is 870 MPa, and the elongation after fracture can reach 17.1%, which is 92.4% of that of the base metal. The impact toughness at the weld is 35 J/cm², reaching 81.8% of that of the base metal. After applying ultrasound, the average residual stress decreased by 96% and the peak residual stress decreased by 94.8% within 10 mm from the weld toe. The average residual stress decreased by 95% and the peak residual stress decreased by 95.5% within 10 mm from the weld root. The residual stress on the surface of the whole welded test plate could be controlled within 200 MPa. Finally, a high-performance thick Ti-alloy plate welded joint with good forming and low residual stress was obtained. Full article

Debonding, especially in plastic materials, refers to the separation occurring at the interface within a bonded structure composed of two or more polymeric layers. Due to the great heterogeneity of materials and layering configurations, highly specialized expertise is often required to detect the presence and extent of such defects. This study presents a novel approach that leverages transfer learning techniques to improve the detection of debonding defects across different surface types using PICUS, an acoustic diagnostic device developed at Roma Tre University for the assessment of defects in heritage wall paintings. Our method leverages a pre-trained deep learning model, adapting it to new material conditions. We designed a planar test object embedded with controlled subsurface cavities to simulate the presence of defects of adhesion and air among the layers. This was rigorously evaluated using non-destructive testing using PICUS, augmented by artificial intelligence (AI). A convolutional neural network (CNN), initially trained on this mock-up, was then fine-tuned via transfer learning on a second test object with distinct geometry and material characteristics. This strategic adaptation to varying physical and acoustic properties led to a significant improvement in classification precision of defect class, from 88% to 95%, demonstrating the effectiveness of transfer learning for robust cross-domain defect detection in challenging diagnostic applications. Full article