1,503 research outputs found

    A Collagenā€Glycosaminoglycanā€Fibrin Scaffold For Heart Valve Tissue Engineering Applications

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    The field of heart valve biology and tissue engineering a heart valve continue to expand. The presentatio ns at this meeting reflect the advances made in both areas due to the multi-disciplinary approach taken by many laboratories

    Scanning electron microscopy image representativeness: morphological data on nanoparticles.

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    A sample of a nanomaterial contains a distribution of nanoparticles of various shapes and/or sizes. A scanning electron microscopy image of such a sample often captures only a fragment of the morphological variety present in the sample. In order to quantitatively analyse the sample using scanning electron microscope digital images, and, in particular, to derive numerical representations of the sample morphology, image content has to be assessed. In this work, we present a framework for extracting morphological information contained in scanning electron microscopy images using computer vision algorithms, and for converting them into numerical particle descriptors. We explore the concept of image representativeness and provide a set of protocols for selecting optimal scanning electron microscopy images as well as determining the smallest representative image set for each of the morphological features. We demonstrate the practical aspects of our methodology by investigating tricalcium phosphate, Ca3 (PO4 )2 , and calcium hydroxyphosphate, Ca5 (PO4 )3 (OH), both naturally occurring minerals with a wide range of biomedical applications

    Mathematical model of pennate muscle.

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    The purpose of this study is to create a new mathematical model of pennate striated skeletal muscle. This new model describes behaviour of isolated flat pennate muscle in two dimensions (2D) by taking into account that rheological properties of muscle fibres depend on their planar arrangement. A new mathematical model is implemented in two types: 1) numerical model of unipennate muscle (unipennate model); 2) numerical model of bipennate muscle (bipennate model). Applying similar boundary conditions and similar load, proposed numerical models had been tested. Obtained results were compared with results of numerical researches by applying a Hill-Zajac muscle model (this is a Hill type muscle model, in which the angle of pennation is taken into consideration) and a fusiform muscle model (a muscle is treated as a structure composed of serially linked different mechanical properties parts)

    Thin film deposition of multilayers on silicon substrate laser pre-patterned

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    In scientific and commericial needs, there was a great demand for the modification of biomaterials that would replace damaged tissue in the body. Today, titanium alloys are mostly used for these purposes in combination with metals of similar physicochemical properties. In this context, there is an increased interest in the development of novel biocompatible materials with enhanced surface interface. The experimental results of a Ti/Zr/Ti thin film system deposited on a substrate pre-patterned by a dynamic femtosecond laser are presented. Surface pattering with micrometre characteristics in the form of spikes is being investigated in order to generate arrayed surface patterns for biomedical pruposes. Femtosecond laser pulses were used to acquire black silicon surfaces adorned with conical structures under 0,65 bar in SF6 ambient pressure. The silicon surface contains high aspect ratio spikes with conical morphologies of about 2Ī¼m, 400 angle opening, and 13Ā·106 cm-2 density that is roughly uniform over the treatment area. Ion sputtering was employed on sech a prepared surface to make a unique composite thin film composed of two layers of Ti and a subsurface layer of Zr. The deposited Ti/Zr/Ti cpomiste has a thickness of 400 nm. The composition and surface morphology were evaluated using FESEM-EDS and XPS methods. Transmission electron spectroscopy and energy dispersive X-ray spectroscopy demonstrated that post-deposition of Ti/Zr/Ti over Si laser-patterned resulted in diffusion of Ti and Zr layers.Twenty-First Young Researchersā€™ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 ā€“ December 1, 2023, Belgrade, Serbi

    Application of polylactide (PLA) biomaterial in various fields of medicine

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    Polylactide (PLA) or polylactic acid is a biodegradable and biocompatible biomaterial obtained from lactic acid, extracted from sugar cane or corn starch. Due to its biocompatibility, after application, it will cause a minimal reaction of the organism, and by virtue of its biodegradability, it will facilitate postoperative recovery because there is no need for its removal. It is often in combination with other compounds to fulfill the requirement about properties which implant need to have. In this review, this will be described in which areas of medicine apply this biomaterial and in which forms. We will see that this material can be made various implants such as surgical sutures, tiles, screws, coatings, capsules and tissue matrices and that this application is especially important in surgical branches of medicine.Twenty-First Young Researchersā€™ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 ā€“ December 1, 2023, Belgrade, Serbi

    Nanofabrication and characterisation of magnetic Fe3O4 nanostructures for potential environmental and biomedical applications

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    Magnetic iron oxide nanomaterials, which enable a multitude of uses, are given special focus in the fields of biomedicine and environmental protection. The detection, sorption, and/or degradation of inorganic (lead, chromium, arsenic, and cadmium), organic (dyes, pharmaceuticals, pesticides, phenols, and benzene), and biological (viruses and bacteria) pollutants can all be effectively accomplished with the use of magnetic nanoparticles. Magnetic iron oxide nanomaterials are in particular focus for use as hyperthermia media in cancer treatment and as magnetic resonance imaging (MRI) contrast agents. The possibility of magnetic separation of such materials, due to their essential properties under the influence of an external magnetic field, reduces production costs and also prevents the production and accumulation of toxic waste. Among the many metal oxide nanomaterials, magnetite (Fe3O4) and maghemite (Ī³-Fe2O3) are currently the only two magnetic materials approved by the US Food and Drug Administration (FDA) for human use as iron deficiency therapeutics and as contrast agents for MRI. Here, we synthesized nanoparticles of magnetite (Fe3O4) by the method of reduction-precipitation and characterized. Additionally, potential binding of brilliant green dye on Fe3O4 and construction of innovative magnetic composite was investigated. The physicochemical features were explored using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM). XRD analysis confirms formation of the crystal phase of magnetite. The presence of magnetite nanoparticles is shown by typical groups for the peaks of iron compounds at a lower wavelength (ā‰¤ 700 cm-1 ) that are characteristic of the Fe-O bond. Morphological analyzes with FESEM showed that magnetite is a composite of nanospheres and nanorods that provide a large surface area. Dye binding study was performed using UVvisible and FTIR spectrometer.Twenty-First Young Researchersā€™ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 ā€“ December 1, 2023, Belgrade, Serbi

    Investigating the influence of hydrothermal treatment on oxygen functional groups in graphene oxide-based nanocomposites

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    Different hierarchical ordering of nanomaterials, either as individual components or in the form of nanocomposites, is one of the approaches used for the development of supercapacitors. In this work, the effect of hydrothermal treatment on oxygen functional groups of nanocomposites between graphene oxide (GO), 12-tungstophosphoric acid (WPA), and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) was examined. The mentioned materials were hydrothermally treated for 4, 8 and 12 hours at 180 Ā°C in order to understand how interaction between the components is influencing development of surface chemistry. The results of Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), and temperature-programmed desorption (TPD) are showing the surface and structural changes of GO (individually and in nanocomposite) as a result of hydrothermal treatment. Both FTIR and RAMAN confirm the presence of WPA and PTCDA. Additionally, it appears that hydrothermal treatment has no impact on the structural changes in PTCDA, which is consistent across various temperature conditions. TPD results indicate that prolonged hydrothermal treatment leads to a gradual increase of the number of functional groups of GO. However, the number of desorbed groups is influenced by the WPA and PTDCA components. This research offers new insights into GO, WPA, and PTCDA interactions which can have useful implications for development of electrochemical supercapacitors.Twenty-First Young Researchersā€™ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 ā€“ December 1, 2023, Belgrade, Serbi

    Physicochemical characterization of mechanochemically activated pyrophyllite/Ag composites

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    Nanocomposites synthesized by incorporating nanostructured materials within the interlayer spaces of clay minerals have gained tremendous interest lately, owing to their exceptional physicochemical properties and vast potential in various fields. This study focuses on the mechanochemical activation of pyrophyllite, a commonly used natural clay material, using AgNO3 at different concentrations (2, 5, and 10 wt%). The activation process involved grinding the materials for varying durations ranging from 20 to 320 minutes. The resulting samples were analyzed using FTIR, TGA, and DTA thermal analysis techniques, XRD, SEM with EDX as well as PSD method for particle size distribution analysis. The results have shown a homogeneous distribution of silver along the analyzed surface. The duration of grinding and the amount of added silver greatly influence the composite physicochemical properties.Twenty-First Young Researchersā€™ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 ā€“ December 1, 2023, Belgrade, Serbi
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