Search

This paper investigates the environmental impact and mechanical performance of two composite sandwich structures, named Series 1 and Series 2, used in high-performance racing boats. Mechanical tests, including four-point bending and drop impact tests, were performed. It was found on a general basis that Series 2 has higher load-bearing capacity and limited deflection. Series 1, which has a higher density, was able to absorb more impact energy but was more susceptible to damage. A Life Cycle Assessment (LCA) was conducted to evaluate the environmental impact associated with the materials, considering also the testing phase, which plays an important role in the life cycle of materials and structures for advanced marine applications. In addition, two performance indexes were introduced to correlate the mechanical and environmental properties of the analyzed materials. This study emphasizes the importance of considering the testing phase in LCA, as the energy-intensive nature of mechanical testing contributes significantly to the overall environmental impact. The introduced indexes allow for a more comprehensive understanding of the balance between mechanical performance and environmental sustainability. The findings suggest a trade-off between mechanical performance and sustainability, calling for further research into recyclable composites and greener manufacturing processes to balance these competing priorities.

The vertebral column represents an essential element for support, mobility, and the protection of the central nervous system. Various pathologies can compromise these vital functions, leading to pain and a decrease in the quality of life. Within the scope of this study, a novel redesign of the Intersomatic Cage, traditionally used in the presence of discopathy, was proposed. The adoption of additive manufacturing technology allowed for the creation of highly complex geometries, focusing on the lumbosacral tract, particularly on the L4-L5 and L5-S1 intervertebral discs. In addition to the tensile analysis carried out using Finite Element Analysis (FEA) in static simulations, a parallel study on the range of motion (ROM) of the aforementioned vertebral pairs was conducted. The ROM represents the relative movement range between various vertebral pairs. The introduction of the intersomatic cage between the vertebrae, replacing the pulpy nucleus of the intervertebral disc, could influence the ROM, thus having significant clinical implications. For the analysis, the ligaments were modelled using a 1D approach. Their constraint reaction and deformability upon load application were analysed to better understand the potential biomechanical implications arising from the adoption of the cages. During the FEA simulations, two types of cages were analysed: LLIF for L4-L5 and ALIF for L5-S1, subjecting them to four different loading conditions. The results indicate that the stresses exhibited by cages with a NET structure are generally lower compared to those of traditional cages. This stress reduction in cages with NET structure suggests a more optimal load distribution, but it is essential to assess potential repercussions on the surrounding bone structure.

In invisible orthodontics, the role of composite attachments in facilitating complex tooth movements is crucial. This study, which evaluates the efficacy of a novel clinical attachment procedure, holds significant implications for the field. The technique used two templates (one pre-drilled and the other pre-loaded with high-viscosity composites) and was compared with the standard procedure. Fifty attachments were planned for four dental arch prototypes. Dental impressions were taken using digital scans for virtual planning and after tested techniques. The stereolithographic files (STL) obtained were aligned with those of the virtual planning, and a colorimetric map was used to evaluate the composite resin’s maximum excess and defect deviation. The enamel–resin interfaces were observed by scanning electron microscopy (SEM). The Fisher test for the distribution of detachments and morphological defects and the Mann–Whitney test for the maximum values of excess and defect were used. No significant results were found between groups for morphological defects and detachments, and the maximum values of defect and excess were reported. SEM images for the experimental technique showed integrated adhesion. This innovative procedure, which has proven reliable and operationally straightforward, holds promise, instilling confidence in its practicality and potential to advance the field of orthodontics.

Intraoral three-dimensional scanning techniques could be used to improve dental practice, leading to an improved overall quality of the prosthetic devices and improved comfort for the patient. An accurate and precise intraoral scanner allows proper diagnosis, follow-up evaluation, and prosthesis application. The aim of this research is to evaluate the precision of an intraoral scanners (Medit i500, Medit Corp., Seoul, Korea), using open-source software in the digital workflow. The precision was compared through repetitions of the scanning process of the upper dental arch, following superimpositions in the whole 3D arch area. It was possible to display colorimetric maps for qualitative comparison, and the deviations of the values were classified as clinically acceptable. Within the limitation of this study, the clinically acceptable in vivo frequency of points’ deviation, or the precision, was obtained in 98.8% ± 1.4%; therefore, the use of open-source software can be a viable option in the digital workflow, improving patient follow ups with the 3D model superimposition.

The use of non-destructive methods guaranteeing high standards of accuracy, speed, simplicity of use, and low costs may be crucial during judicial inspection aimed to reconstruct the spatial arrangement of crime scenes. Three-dimensional (3D) laser scanning and structured blue light scanning are two modern and advanced technologies widely used in many sectors of the sciences, included forensic sciences. Limiting itself to forensic applications, these technologies may be successfully used for acquiring point clouds in 3D space and reconstruct 3D virtual models of large-, medium-, and small-scale forensic scenarios. These two technologies were applied for reconstructing 3D virtual models from real crime scenes and geological evidence, respectively. Different investigative places and items were investigated and discussed. The research evidenced the advantages of using these modern techniques in order to assist investigators in: i) providing 3D virtual models for reconstructing even complex crime scenes occurred outdoor; ii) reconstructing of the dynamics of events, and iii) individuating possible interactions between the actors of the scene and the surrounding places.

The paper reports the results of training experiences in the field of education in forensic and biomedical sciences carried out during two editions of summer schools. Two simulated serious crimes, involving dummies used as victims, were prepared for practitioners in outdoor places. The scenes simulate a suspect murder case of homicide with staging and a corpse concealment with dismembered human remains found into a clandestine grave, respectively. During the simulations, laser scanning technology was applied to reproduce the outdoor crime scenes in order to verify the capacity of the innovative technique as advantageous tool during educational and forensic training. Judicial inspections conducted during the simulation provided preliminary physical evidence, in the fields of forensic medicine, forensic geology, and engineering, highlighting the importance of the multidisciplinary approach. These experiences, through the use of the laser scanner that allowed for the recreation of virtual environments in which practitioners were able to confront crime scenes, demonstrated how such an approach can be useful in education and training activities.

The multidisciplinary approach has become an almost indispensable requirement in the examination of the scena criminis, especially in complex cases involving different professional profiles within the biomedical and forensic sciences. In recent times, innovative methods have been joined by the possibility of using three-dimensional laser scanners, capable of obtaining virtual reconstructions, very useful in analyzing outdoor or indoor crime scenes. In the present paper, three case studies regarding simulated indoor and outdoor crime scenes were analyzed, applying a virtual reconstruction based on a survey and acquisition of “point clouds” by using a laser scanner Leica BLK360, managed by means of the software Leica Cyclone. Victims were simulated by two hyper-realistic dummies produced by the Lifecast Body Simulation. The first crime scene regarded a suspect homicide case of a man found hanged to a metallic rod indoor, inside a room; the second crime scene regarded a homicide case of a woman, suspected to be victim of sexual assault, found indoor, on the floor of a corridor in a palace; the third scene regarded an outdoor place located in the hills of the Peloritani Mountains, simulating a crime scene where a homicide was committed. The advantages and disadvantages of virtual three-dimensional acquisitions in relation to forensic purposes were finally highlighted. The successful outcome of the scans proved the true-to-life reproducibility of virtual targets, with the possibility of easier interactions, the possibility to measure specific parameters, adequate simulations, and the essential “crystallization” of physical evidence. In the next future, it will be important improving the procedure in order to obtain protocols with high quality standards, able to ensure that the acquired data will be considered valid with evidentiary effect in judicial trials.

In Forensic Geology, color examination of sediments and soils is one of the first analyses for exclusionary/comparative purposes. Forensic colorimetry deals with the examination of the color of physical evidence related to criminal investigations. Color of soils and sediments has always been considered an essential parameter and one of the most common and crucial visually physical property for characterizing, describing, and comparing these geological materials, since the first steps of forensic investigations. This parameter may be evaluated both qualitatively and quantitative. In forensic comparative analyses of sediments and soils, most of the colorimetric methods are nowadays computational. These computational instruments, provided of standards and standardized illumination conditions, may obtain very high-resolution and non-destructive quantitative data. When adapted to sedimentological applications for forensic purposes, photometric instrumentations are powerful tools due to their low purchase and maintenance costs. Moreover, some devises are also portable and easily used at the crime scene. Recent advances in the colorimetry research showed as also the simple use of digital devises, such as low-cost flatbed scanners, may be easily applied for the color examination of acquired color images of sediments and soils, if calibrated with standards, as reference charts or database. The results of a simulated forensic casework devoted to the comparative analysis of the color of soils, acquired by means low-cost flatbed scanner, confirmed previous results on this useful application.

The naval sector holds paramount importance for the global economy, yet it entails significant environmental impacts throughout the entire life cycle of ships. This review explores the application of life-cycle assessment (LCA) in the naval sector, a methodology for evaluating the environmental impacts associated with all the life stages of a product or service. LCA analysis in the naval context is essential for identifying and mitigating environmental impacts, thus promoting more sustainable development of the sector. This work provides a comprehensive overview of current LCA applications in the naval sector, highlighting major environmental impacts, in particular focusing on greenhouse-gas emissions and climate change. Additionally, this study integrates an analysis of greenhouse-gas emissions using a normalization approach, which has enabled the comparison of various types of fuels and ships, thereby enhancing our understanding of their environmental impacts. Moreover, the limits and challenges to applying LCA in the naval sector are discussed, offering insights for future research and developments in the field. This review aims to raise awareness among policymakers, designers, and operators in the naval sector about the importance of adopting LCA for more sustainable and responsible management of naval activities, thereby contributing to the protection of the marine and global environment.

In this study, the effectiveness of an experimental clinical technique for the reproduction of attachments during an orthodontic treatment with clear aligners was evaluated using a new index (CorAl) for quality assessment that exploits the differential entropy of point clouds. The procedure involves the use of a pre-drilled template and a second pre-loaded template with a high-viscosity composite and is compared with the standard technique. Attachment planning was conducted on four prototypes of dental arches with extracted teeth which were divided into two groups according to the proposed operating procedures. Digital scans were utilized to capture dental impressions for both the purposes of virtual planning and to reproduce the clinical outcomes post-procedure. The point clouds obtained after the reproduction of the attachments were aligned with those from the virtual planning, and the deviation analysis was conducted using the quality index of the CorAl method. Though no significant discrepancies were found among the groups regarding morphological flaws, detachments, or maximum defect values, the differential entropy analysis revealed that the experimental technique offers good alignment in attachment placement. The outcome supports that the innovative procedure of the clinical reproduction of attachments proved to be reliable and operationally simple, with additional benefits derived from using the CorAl index. The advantages of CorAl include the use of a single comparison index, no problem of comparison commutativity, noise immunity, low influence from the presence of holes, and point cloud densities. This allows for the drawing of quality maps that show areas with the highest deviation.

Joining is critical in shipbuilding impacting significantly on several aspects, i.e., properties, lightness, aesthetics, assembly/disassembly, maintenance employed workforce, emissions of fumes or gases. Consequently, it requires a significant study on impacts and risks. The aim of this work is to apply the Life Cycle Assessment to a friction stir welding process between aluminium and steel. The results confirmed that this welding is among the most sustainable (i.e., low energy, absence of filler, inert gases, and consumables). Moreover, was introduced a functional unit (i.e., length of weld divided by the thickness squared) that allows to compare different geometries and process parameters.