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In the field of three-dimensional object design and fabrication, this paper explores the transformative potential at the intersection of biomaterials, biopolymers, and additive manufacturing. Drawing inspiration from the intricate designs found in the natural world, this study contributes to the evolving landscape of manufacturing and design paradigms. Biomimicry, rooted in emulating nature's sophisticated solutions, serves as the foundational framework for developing materials endowed with remarkable characteristics, including adaptability, responsiveness, and self-transformation. These advanced engineered biomimetic materials, featuring attributes such as shape memory and self-healing properties, undergo rigorous synthesis and characterization procedures, with the overarching goal of seamless integration into the field of additive manufacturing. The resulting synergy between advanced manufacturing techniques and nature-inspired materials promises to revolutionize the production of objects capable of dynamic responses to environmental stimuli. Extending beyond the confines of laboratory experimentation, these self-transforming objects hold significant potential across diverse industries, showcasing innovative applications with profound implications for object design and fabrication. Through the reduction of waste generation, minimization of energy consumption, and the reduction of environmental footprint, the integration of biomaterials, biopolymers, and additive manufacturing signifies a pivotal step towards fostering ecologically conscious design and manufacturing practices. Within this context, inanimate three-dimensional objects will possess the ability to transcend their static nature and emerge as dynamic entities capable of evolution, self-repair, and adaptive responses in harmony with their surroundings. The confluence of biomimicry and additive manufacturing techniques establishes a seminal precedent for a profound reconfiguration of contemporary approaches to design, manufacturing, and ecological stewardship, thereby decisively shaping a more resilient and innovative global milieu.
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The practical, rapid, and accurate optical 3D reconstruction of transparent objects with contemporary non-contact optical techniques, has been an open challenge in the field of optical metrology. The combination of refraction, reflection, and transmission in transparent objects makes it very hard to use common off-the-shelf 3D reconstruction solutions to accurately reconstruct transparent objects in three dimensions without completely coating the object with an opaque material. We demonstrate in this work that a specific class of transparent objects can indeed be reconstructed without the use of opaque spray coatings, via Optical Projection Tomography (OPT). Particularly, the 3D reconstruction of large thin-walled hollow transparent objects can be achieved via OPT, without the use of refractive-index-matching liquid, accurately enough for use in both cultural heritage and beverage packaging industry applications. We compare 3D reconstructions of our proposed OPT method to those achieved by an industrial-grade 3D scanner and report average shape differences of ±0.34 mm for 'shelled' hollow objects and ±0.92 mm for 'non-shelled' hollow objects. A disadvantage of using OPT, which was noticed on the thicker 'non-shelled' hollow objects, as opposed to the 'shelled' hollow objects, was that it induced partial filling of hollow areas and the deformation of embossed features.
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The emerging field of regenerative medicine holds immense promise for addressing complex tissue and organ regeneration challenges. Central to its advancement is the evolution of additive manufacturing techniques, which have transcended static constructs to embrace dynamic, biomimetic solutions. This manuscript explores the pivotal role of smart materials in this transformative journey, where materials are endowed with dynamic responsiveness to biological cues and environmental changes. By delving into the innovative integration of smart materials, such as shape memory polymers and stimulus-responsive hydrogels, into additive manufacturing processes, this research illuminates the potential to engineer tissue constructs with unparalleled biomimicry. From dynamically adapting scaffolds that mimic the mechanical behavior of native tissues to drug delivery systems that respond to physiological cues, the convergence of smart materials and additive manufacturing heralds a new era in regenerative medicine. This manuscript presents an insightful overview of recent advancements, challenges, and future prospects, underscoring the pivotal role of smart materials as pioneers in shaping the dynamic landscape of regenerative medicine and heralding a future where tissue engineering is propelled beyond static constructs towards biomimetic, responsive, and regenerative solutions.
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Medicina Regenerativa , Materiales Inteligentes , Materiales Biocompatibles , Biomimética/métodos , Impresión Tridimensional , Medicina Regenerativa/métodos , Ingeniería de Tejidos/métodosRESUMEN
The emergence of additive manufacturing technologies has brought about a significant transformation in several industries. Among these technologies, Fused Deposition Modeling/Fused Filament Fabrication (FDM/FFF) 3D printing has gained prominence as a rapid prototyping and small-scale production technique. The potential of FDM/FFF for applications that require improved mechanical, thermal, and electrical properties has been restricted due to the limited range of materials that are suitable for this process. This study explores the integration of various reinforcements, including carbon fibers, glass fibers, and nanoparticles, into the polymer matrix of FDM/FFF filaments. The utilization of advanced materials for reinforcing the filaments has led to the enhancement in mechanical strength, stiffness, and toughness of the 3D-printed parts in comparison to their pure polymer counterparts. Furthermore, the incorporation of fillers facilitates improved thermal conductivity, electrical conductivity, and flame retardancy, thereby broadening the scope of potential applications for FDM/FFF 3D-printed components. Additionally, the article underscores the difficulties linked with the utilization of filled filaments in FDM/FFF 3D printing, including but not limited to filament extrusion stability, nozzle clogging, and interfacial adhesion between the reinforcement and matrix. Ultimately, a variety of pragmatic implementations are showcased, wherein filled filaments have exhibited noteworthy benefits in comparison to standard FDM/FFF raw materials. The aforementioned applications encompass a wide range of industries, such as aerospace, automotive, medical, electronics, and tooling. The article explores the possibility of future progress and the incorporation of innovative reinforcement materials. It presents a plan for the ongoing growth and application of advanced composite materials in FDM/FFF 3D printing.
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COVID-19 pandemic outbreak dictated the extensive use of personal protective equipment (PPE) by the majority of the population and mostly by frontline professionals. This need triggered a sudden demand that led to a global shortage of available PPEs threatening to have an immense contribution to the virus contamination spread. In these conditions, the need for a local, flexible, and rapid manufacturing method that would be able to cope with the increased demand for PPE fabrication arose. 3D printing proved to be such a manufacturing technique since its working principles make it an ideal technology for local, decentralized production of PPEs meeting the local demands. While considered to be more environmentally friendly than conventional fabrication techniques and aligning well with the principles of sustainability and circular economy, 3D printing can produce waste as the result of potential failed prints and material used for the fabrication of support structures. This paper describes the case of utilizing pre-existing FDM 3D printing equipment in an academic facility for the production of PPEs (face shields) and their distribution according to local demands. The plastic wastes produced were forwarded to a recycling process that led to their conversion to 3D filament that would be returned to the academic facility as raw material for future 3D printing operations. The followed procedure minimized 3D printing waste and led to a zero-waste fabrication case that was initiated in a pandemic for a greater-good cause (production of COVID-19 fighting PPEs) while assimilating the values of sustainability and circular economy.
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[This corrects the article DOI: 10.1007/s43615-021-00047-8.].
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Hip fractures occur commonly and are a cause of disability for older adults and lead to increased dependence and requirements for social support. Dementia is one of the possible risk factors for falling and hip fracture, a potential source for complications during surgery and during the postoperative period, difficulties in rehabilitation and a risk factor for hip fracture reccurence. However, in previous studies of hip fracture patients, cognitive status has not been formally assessed during the inpatient stay and diagnosis was based only on previous history. Additionally, no previous studies have compared prevalence of dementia between elderly patients with hip fracture and patients with other surgical pathology. Our aim was to define whether dementia was more prevalent in older subjects with hip fracture than in other elderly patients undergoing surgery. In this study, we prospectively assessed all patients aged 68 and older admitted to our hospital for hip fracture surgery during a one year period and compared them with age and gender matched patients attending other surgical departments. 80 hip fracture patients and 80 controls were assessed for dementia. Dementia was common in both groups, presumably reflecting the advanced mean age of both groups and cognitive deterioration due to hospitalization-status. Dementia was significantly higher in the hip fracture group (85%) compared to the control group (61.5%; p=0.002). Dementia is very common in older patients admitted for surgery to a general hospital and extremely common in those with hip fracture. It seems that dementia is under diagnosed in elderly hospitalised patients. Our data confirm that dementia is a major risk factor for hip fracture in the elderly.
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Demencia/epidemiología , Fracturas de Cadera/epidemiología , Complicaciones Posoperatorias/epidemiología , Anciano , Anciano de 80 o más Años , Comorbilidad , Demencia/diagnóstico , Femenino , Anciano Frágil/psicología , Grecia/epidemiología , Fracturas de Cadera/psicología , Fracturas de Cadera/rehabilitación , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Prevalencia , Estudios Prospectivos , Factores de RiesgoRESUMEN
Parkinsonism in hip fracture (HF) patients is a potential source for complications during surgery, postoperative period and rehabilitation and a risk factor of second HF. We investigated whether parkinsonism was more prevalent in older subjects with HF than in other older patient groups undergoing surgery. We prospectively assessed patients who had suffered HF and controls. We assigned all patients aged 68 and older admitted in our hospital for HF surgery during last year and compared them with age- and gender matched patients attending other surgical departments. 80 HF patients and 80 controls were assessed for parkinsonism. Parkinsonism was common in both groups, presumably reflecting the mean ages of approximately 80 years, plus hospitalization-status. However, parkinsonism was much higher in the hip fracture group (76.25%) compared to the control hospitalised subjects (37.5%; p<0.001). The majority of HF patients with parkinsonism were undiagnosed for their parkinsonism symptoms prior to HF and the same was observed in the control group (91.8% and 86.7% respectively, p= 0.471). Among those with parkinsonism, pre-hospitalization drug therapy may have been contributory in 24.5% of HF patients and 30% of controls (p=0.589). Parkinsonism is very common in older patients admitted for surgery to a general hospital and extremely common in those with HF. It seems that parkinsonism, is heavily under recognised in the elderly. Our data seem to confirm that parkinsonism is a major risk factor of HF in the elderly.