8 research outputs found

    Morphological study of the iris musculature in diurnal and nocturnal raptors

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    In literature it is established that the iris musculature consists of striate muscle fibers in birds while in mammals it consists of smooth muscles. Some authors report the presence of smooth muscle tissue also in the iris of some species of birds. In the present study we report on the iris muscle tissues (type of tissue, direction and mean diameter of muscle fibers or cells) in five species of Accipitriformes (diurnal raptors) and four species of Strigiformes (nocturnal raptors) because they show different way of life depending of their predatory behavior. This morphological study was carried out from raptors died or euthanized at the Wild Life Rescue Centre of Sea and Water birds in Livorno (Italy). From histological examination of iris serial radial sections we find both striated and smooth musculature even if with marked differences among analyzed species, not directly correlated with diurnal or nocturnal lifestyle. Striated fibers are always present, mainly with cross direction, throughout the iris stroma, while the histological differences concern the smooth cells. Indeed, harrier and sparrow hawk (Accipitriformes) and great horned owl and little owl (Strigiformes) show a compact layer of cross smooth muscle cells throughout the iris stroma. In the other species analyzed smooth muscle cells are slightly detectable as scattered or not detectable. Since the cross smooth muscle tissue allows to maintain a myotic state for extended periods of time, our results might be correlated more to the predatory behavior than the taxonomic order

    Upscaling of Electrospinning Technology and the Application of Functionalized PVDF-HFP@TiO2 Electrospun Nanofibers for the Rapid Photocatalytic Deactivation of Bacteria on Advanced Face Masks

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    In recent years, Electrospinning (ES) has been revealed to be a straightforward and innovative approach to manufacture functionalized nanofiber-based membranes with high filtering performance against fine Particulate Matter (PM) and proper bioactive properties. These qualities are useful for tackling current issues from bacterial contamination on Personal Protective Equipment (PPE) surfaces to the reusability of both disposable single-use face masks and respirator filters. Despite the fact that the conventional ES process can be upscaled to promote a high-rate nanofiber production, the number of research works on the design of hybrid materials embedded in electrospun membranes for face mask application is still low and has mainly been carried out at the laboratory scale. In this work, a multi-needle ES was employed in a continuous processing for the manufacturing of both pristine Poly (Vinylidene Fluoride-co-Hexafluoropropylene) (PVDF-HFP) nanofibers and functionalized membrane ones embedded with TiO2 Nanoparticles (NPs) (PVDF-HFP@TiO2). The nanofibers were collected on Polyethylene Terephthalate (PET) nonwoven spunbond fabric and characterized by using Scanning Electron Microscopy and Energy Dispersive X-ray (SEM-EDX), Raman spectroscopy, and Atomic Force Microscopy (AFM) analysis. The photocatalytic study performed on the electrospun membranes proved that the PVDF-HFP@TiO2 nanofibers provide a significant antibacterial activity for both Staphylococcus aureus (~94%) and Pseudomonas aeruginosa (~85%), after only 5 min of exposure to a UV-A light source. In addition, the PVDF-HFP@TiO2 nanofibers exhibit high filtration efficiency against submicron particles (~99%) and a low pressure drop (~3 mbar), in accordance with the standard required for Filtering Face Piece masks (FFPs). Therefore, these results aim to provide a real perspective on producing electrospun polymer-based nanotextiles with self-sterilizing properties for the implementation of advanced face masks on a large scale

    Preservation and Reproduction of an Ancient Human Humerus through X-ray Microscopy and 3D Printing

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    The combination of X-ray Microscopy (XRM) and three-dimensional virtual reconstruction has enabled the digitization and restoration of broken artifacts. By scanning, acquiring, and virtually stitching together the 3D reconstructions of individual broken pieces, damaged relics can be visualized as if they were intact objects. These virtually reconstructed samples can then be reproduced as physical copies through 3D printing, allowing for the sharing of rare findings in museum exhibits worldwide so that printed copies can be displayed for public exposure, while the original pieces remain preserved. This paper aims to demonstrate the application of these reconstruction principles to an artificially modified human humerus belonging to the II–I millennium BC. The humerus was bent into the shape of a serpent for ritual purposes related to the ancient "Snake Cult", which was widespread in the Persian Gulf area during the Iron Age. Following the scanning and software elaboration processes, the pieces were printed in PLA (Polylactic Acid) as a single object and made available to the public, thus giving new life to a unique piece of history

    Preservation and reproduction of an ancient human humerus through x-ray microscopy and 3D printing

    No full text
    The combination of X-ray Microscopy (XRM) and three-dimensional virtual reconstruction has enabled the digitization and restoration of broken artifacts. By scanning, acquiring, and virtually stitching together the 3D reconstructions of individual broken pieces, damaged relics can be visualized as if they were intact objects. These virtually reconstructed samples can then be reproduced as physical copies through 3D printing, allowing for the sharing of rare findings in museum exhibits worldwide so that printed copies can be displayed for public exposure, while the original pieces remain preserved. This paper aims to demonstrate the application of these reconstruction principles to an artificially modified human humerus belonging to the II–I millennium BC. The humerus was bent into the shape of a serpent for ritual purposes related to the ancient “Snake Cult”, which was widespread in the Persian Gulf area during the Iron Age. Following the scanning and software elaboration processes, the pieces were printed in Polylactic Acid (PLA) as a single object and made available to the public, thus giving new life to a unique piece of history

    A LoRaWAN Multi-Technological Architecture for Construction Site Monitoring

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    It is necessary to ensure safety in terms of health and accidents through the real-time monitoring of the construction site environment and workers. This problem has become of great importance due to the economic and social implications. Therefore, a sensor-based approach has been found to be beneficial in Building Information Modeling (BIM). Wireless Sensor Network (WSN) technologies are well-suited for the deployment of monitoring systems. A suitable technical solution for node communication in a WSN is Long Range (LoRa) modulation technology. In this study, an autonomous LoRa-based system for the monitoring of a construction site in Lungro, Calabria, Italy, is presented. The spatial monitoring of working personnel is achieved by employing a tracker device with an Inertial Measurement Unit (IMU) and a Global Positioning System (GPS) device. Accesses of personnel and gear to the site are registered using Radio Frequency Identification (RFID) tags equipped with protective gear. Fixed-position solar-powered sensor nodes are also employed for structural monitoring, i.e., movement sensors are used to monitor the variation of scaffolding, building structures, and under-work housing inclinations. Long Range Wide Area Network (LoRaWAN) gateways interface with the nodes and the internet for data exchange, enabling an Internet of Things (IoT) paradigm for the monitoring solution. A comprehensive overview of the workers and structural nodes, along with the RFID access management system and LoRaWAN gateway features, is provided in this article. A description of the web interface is also reported

    Electrospinning technology to upscale the production of low-cost and high-filtering functionalized polymer-based nanofibers providing photocatalytic activity for bacterial inactivation in advanced face mask

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    The importance to produce polymer-based membranes with suitable self-cleanable properties in preventing high risk of contamination on the fabric for long time usage has been becoming a relevant issues, especially in the last years when the pandemic outbreak of the Coronavirus disease (COVID-19) have brought to a mass consumption of personal protective equipment (PPE), such as face mask/respirators, which resulted in a potential source of further contamination from bacteria or virus. Modified electrospinning set-ups combined with modern textile techniques turned out to be an innovative way to manufacture nanofiber-based membrane showing high filtering performance against submicron pollution particles and suitable bioactive properties for tackling the current issues from bacterial contamination on PPE surfaces to the reusability of both disposable single use facemask and respirator’s filters [1]. With this paper we aim to provide further insight about the development of advanced electrospun nanofibrous photocatalytic membranes for large scale production. Investigation on the effects of processing variables on the fabrication of functionalized electrospun nanofibers embedded with active NPs for the scale-up line have been carried out by using Scanning Electron Microscopy and Energy Dispersive X-ray (SEM-EDX), Atomic Force Microscopy (AFM), and Raman spectroscopy analysis. In addition, photocatalytic disinfection for some bacteria strains, were conducted on the hybrid polymer-based membranes under UV-A light exposition by using the pristine electrospun membranes as control in the colony count method [2]. Finally, to provide a real perspective for the application of nanotextile in the manufacturing of advanced face mask on large-scale, both particle filtration and breathability test were also conducted on the nanofiber mats, in accordance with the standard required for Filtering Face Piece masks (FFP). [1] Cimini A., E. Imperi, A. Picano, M. Rossi. Electrospun nanofibers for medical face mask with protection capabilities against viruses: State of the art and perspective for industrial scale-up. Applied Materials Today, 2023, (32) 101833. [2] Q. Li, Y. Yin, D. Cao, Y. Wang, P. Luan, X. Sun, W. Liang, H. Zhu, Photocatalytic rejuvenation enabled self-sanitizing, reusable, and biodegradable masks against COVID-19, ACS Nano, 2021, 15 (7), 11992–12005
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