Τμήμα Επιστήμης & Μηχανικής Υλικών
17 Νοεμβρίου 2024
Ο Πρόεδρος του Τμήματος Επιστήμης και Μηχανικής Υλικών Αναπληρωτής Καθηγητής Δ. Παπάζογλου σας προσκαλεί στην τελετή αποφοίτησης την
Δείτε την Πρόσκληση Τελετής Αποφοίτησης.
01 Νοεμβρίου 2024
Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής της
κ. Βαρβάρας Πλατανιά
Επιβλέπουσα Καθηγήτρια: Μαρία Χατζηνικολαΐδου
(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)
Την Τρίτη 5 Νοεμβρίου 2024 και ώρα 11:00 στην αίθουσα Τηλεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής της υποψήφιας διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Βαρβάρας Πλατανιά, με θέμα:
«3D Bioprinting of Vascularized Bone Grafts Using Human Adult Stem Cells and Cell-Instructive Biomaterials under Mechanical Stimulation»
Περίληψη
Current medical practice still faces significant challenges in treating large bone defects caused by trauma or disease. The main causes of large graft failure are inner graft necrosis and lack of integration with the host tissue due to poor vascularization. Developing bone grafts that can restore vascular function to the regenerating bone tissue has been the most difficult aspect to address. This thesis explores the critical role of vascularization in enhancing bone tissue engineering outcomes.
Acknowledging the potential of 3D bioprinting in bioengineering complex tissues, this study introduces a dual-layered 3D bioprinted vascularized bone model aiming to promote bone regeneration under physiological mechanical loading. The inner layer comprises a vascular-like matrix created from a nanocomposite ink of gellan gum, laponite, and platelet-rich plasma (PRP), with laponite serving as a carrier for the PRP-containing bioactive growth factors, along with Wharton-jelly mesenchymal stem cells. The outer layer features a bone-like matrix containing bone marrow mesenchymal stem cells encapsulated in a photocrosslinkable blend of poly(ethylene glycol) diacrylate (PEGDA), gelatin, and poly(vinyl alcohol). The electrically conductive poly(3,4-ethylenedioxythiophene) (PEDOT) is introduced in the outer layer to enhance the activity of voltage-gated channels, facilitating calcium ion flow across the cell membrane, amplifying the signal triggered by mechanical stimulation.
Dynamic cell cultures performed in the presence of mechanical stimulation within a bioreactor were employed to mimic the physiological environment of native bone tissue. The synergistic cellular and molecular interactions of the dual-layered constructs significantly enhance the osteogenic and angiogenic differentiation due to paracrine signaling. Key markers of osteogenesis and angiogenesis showed significant upregulation in response to mechanical stimulation, particularly in the dynamic cultures. The complex bioprinted constructs demonstrated excellent in vitro biocompatibility, without observing any adverse foreign body reaction following in vivo subcutaneous implantation in mice. The mechanoresponsive biofabricated platform has great potential to promote vascularized bone regeneration.
30 Οκτωβρίου 2024
Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής
του κ. Νικολάου-Αθανασίου Μπούρκερ
Επιβλέπων: Benoit Loppinet
(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)
Την Τρίτη 5 Νοεμβρίου 2024 και ώρα 14:00 στην αίθουσα Τηλεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Νικολάου-Αθανασίου Μπούρκερ, με θέμα:
«Rheology and Μicrorheology at Ηigh Pressures»
ΠερίληψηIn this dissertation we report experimental investigations of the dynamics, the phase and flow behavior of three systems, Organoclay, Supramolecular organogels, and gelatin. They are gelling dispersions. They form weak solids despite the low volume fraction. Of-ten out of equilibrium, such gels are sensitivity to weak perturbations and show strong dependence on the preparation and environmental conditions or external fields. Their flow behaviors and controls at given environmental conditions (pressure, temperature, humidity etc.) are of broad interest and valuable in multiple applications (energy, food and polymer industry).
We use scattering, rheology and microrheology to probe the dynamics, the linear and non-linear viscoelastic responses. Particular attention is given to high pressure (HP) conditions, as it is not much reported. Light scattering based passive HP-microrheology was developed and used to measure linear viscoelasticity. HP-shear rheology was also used for flow curves. When needed complementary structural characterization was per-formed through spectroscopy techniques and rheo – SAS (light and x-ray).
In organoclay dispersions (Ch. 3,4,5) we explore the effects of preparation treatment and we propose efficient ways to control the rheology and structure (clay exfoliation) through the construction of phase diagrams in clay concentration, homogenization temperature and water content space. We established shear history protocols and effectively tuned their mechanical properties without affecting much the structure. We monitor the evolution of organoclay dispersions and a model oil continuous drilling fluid at different pressures and aging.
We study the linear viscoelastic response and we construct phase diagrams of supramolecular organogels, (EHUT) at pressure, temperature and concentration (Ch. 6,7). We elucidate the effect of pressure and temperature on the linear viscoelasticity and attribute it to small variation in the self-assembly.
We study the effect of pressure (and concentration) on sol-gel transition of gelatin solutions (Ch. 8). We established that the gelation time decreases with increasing pressure, i.e., gelation speeds up. It is governed by the distance to the collagen denaturation temperature, known to increase with pressure by 0.04 K/Mpa.
29 Οκτωβρίου 2024
ΠΑΝΕΠΙΣΤΗΜΙΟ ΚΡΗΤΗΣ
ΤΜΗΜΑ ΕΠΙΣΤΗΜΗΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ ΥΛΙΚΩΝ
ΠΑΡΟΥΣΙΑΣΗ ΜΕΤΑΠΤΥΧΙΑΚΗΣ ΔΙΠΛΩΜΑΤΙΚΗΣ ΕΡΓΑΣΙΑΣ
Τίτλος
«Functionalized Electrospun Nanofibrous Membranes with Antimicrobial Activity for Wound Healing»
της Νεράϊντα Πετράι
μεταπτυχιακής φοιτήτριας του Τμήματος Επιστήμης και Μηχανικής Υλικών του Πανεπιστημίου Κρήτης
Επιβλέπουσα Καθηγήτρια: Μαρία Χατζηνικολαΐδου
Δευτέρα 4 Νοεμβρίου 2024 Ώρα 10:00
H παρουσίαση θα πραγματοποιηθεί στην αίθουσα Τηλε-εκπαίδευσης (Ε130), στο κτήριο του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών, του Πανεπιστημίου Κρήτης
Abstract
Chronic wounds affect a significant percentage of the world population suffering from serious diseases. Therefore, there is a growing interest in the development of tissue-engineered scaffolds from natural and synthetic biomaterials to mimic natural skin. Researchers have attempted to functionalize the scaffolds with bioactive molecules to resist the bacterial infections that often develop on impaired wounds. Curcumin (Cur) has been reported to promote wound healing due to its many biological activities. Recently, the electrospraying technique has emerged for precise deposition of bioactive molecules into scaffolds to improve therapeutic outcomes. In this study, we aimed to produce scaffolds for wound healing and endow them with antibacterial properties to promote the healing of impaired wounds. Toward this end, we fabricated four types of membranes, poly(vinyl alcohol) PVA and PVA/kappa carrageenan (KC) using the electrospinning method and PVA/KC/Cur5, PVA/KC/Cur20, in which the PVA/KC membranes were coated with two different concentrations of Cur by electrospraying. All membranes showed low cytotoxicity, good cell adhesion, capability of enabling cells to produce collagen, and an adequate degradation rate for wound healing applications. Antibacterial studies showed that both Cur-loaded membranes increased antibacterial efficacy against both types of bacteria, Escherichia coli and Staphylococcus aureus, compared to PVA and PVA/KC membranes. Overall, these results suggest that coating Cur on the PVA/KC membranes using the electrospraying method is a potential therapeutic strategy for wound healing.
21 Οκτωβρίου 2024
ΠΑΝΕΠΙΣΤΗΜΙΟ ΚΡΗΤΗΣ
ΤΜΗΜΑ ΕΠΙΣΤΗΜΗΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ ΥΛΙΚΩΝ
ΠΑΡΟΥΣΙΑΣΗ ΜΕΤΑΠΤΥΧΙΑΚΗΣ ΔΙΠΛΩΜΑΤΙΚΗΣ ΕΡΓΑΣΙΑΣ
Τίτλος
«Development of AgI-AgPO3 Glass Microwire Based Photoactuators»
του Χαράλαμπου Γωνιωτάκη
μεταπτυχιακού φοιτητή του Τμήματος Επιστήμης και Μηχανικής Υλικών του Πανεπιστημίου Κρήτης
Επιβλέπων: Εμμανουήλ Στρατάκης
Παρασκευή 25 Οκτωβρίου 2024, Ώρα 10:00
H παρουσίαση θα πραγματοποιηθεί στην αίθουσα Τηλε-εκπαίδευσης (Ε130), στο κτήριο του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών, του Πανεπιστημίου Κρήτης
Abstract
Over the years significant scientific attention has been given towards the design of advanced photoactuating architectures as they are important elements for various optical tweezers, grippers, and soft robot applications. Most of the currently available photoactuators, rely on the existence of a free-space illumination pathway from the light sources to the device or on the employment of bendable optical fibers, while consisting of two or more elements, i.e. the photoactuating material and the substrate. Herein, we report on a facile method of preparing single-component pristine microwires (MWs) that exhibit photoactuating features upon utilizing a soft phosphate glass doped with silver nanoparticles (AgNPs), without the need of any additional photoactuating element. The developed photoactuators exhibited bending angles of around 110°, within a couple of seconds. In addition, we have fabricated double-component polymer-coated phosphate glass MWs photoactuators, upon employing PDMS coatings on the surface of the so-formed glass MWs. The introduction of the polymer component boosts the bending angle of the photoactuating device to over 200° within the a few seconds upon modest laser irradiation. The presence of AgNPs within the glass MWs, play a key role on the remarkable performance of the developed photoactuators, both in terms of actuating angles as well as of the respective response times, since they assist on the effective transmission of laser irradiation energy to thermal energy. The fabrication method reported here appears promising for the development of high-performance and low-cost free-space, as well as fiber-based photoactuators.
16 Οκτωβρίου 2024
Νέος Συνήγορος του Φοιτητή έχει οριστεί ο Ομότιμος Καθηγητής της Ιατρικής Σχολής του Πανεπιστημίου Κρήτης, Χρήστος Λιονής, σύμφωνα με απόφαση της Συγκλήτου.10 Οκτωβρίου 2024
ΠΑΝΕΠΙΣΤΗΜΙΟ ΚΡΗΤΗΣ
ΤΜΗΜΑ ΕΠΙΣΤΗΜΗΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ ΥΛΙΚΩΝ
ΠΑΡΟΥΣΙΑΣΗ ΜΕΤΑΠΤΥΧΙΑΚΗΣ ΔΙΠΛΩΜΑΤΙΚΗΣ ΕΡΓΑΣΙΑΣ
Τίτλος
«Multiscale Computational Study of Drug Encapsulation and Delivery by Porous Materials»
του Μιχαήλ Βλάχου
μεταπτυχιακού φοιτητή του Τμήματος Επιστήμης και Μηχανικής Υλικών του Πανεπιστημίου Κρήτης
Επιβλέπων Καθηγητής: Γεράσιμος Αρματάς
Τετάρτη 23 Οκτωβρίου 2024 Ώρα 11:00
H παρουσίαση θα πραγματοποιηθεί στην αίθουσα Τηλε-εκπαίδευσης (Ε130), στο κτήριο του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών, του Πανεπιστημίου Κρήτης
Abstract
Zeolitic Imidazolate Frameworks (ZIFs) are considered as potential nanocarriers in biomedical applications such as storage and transportation of drugs, due to their low toxicity, high internal load and controlled release. In this work, the adsorption of the anticancer drug 5-Fluorouracil (5-FU) in selected ZIFs is studied by employing a multiscale computational scheme that includes semi-empirical computational techniques (PM7), Grand Canonical Monte Carlo and Molecular Dynamics simulations. Our investigation is based on ZIF-8 which is characterized by pH-sensitive controlled drug release. In order to improve the drug interaction with the framework we expanded the parent ZIF-8, by replacing each imidazole linker with 3-(1H-pyrrol-3-yl)-pyridine. 5-FU shows enhanced binding affinity (34 kcal/mol) in modified ZIF with respect to the parent ZIF-8 (12 kcal/mol) (PM7). Moreover, Grand Canonical Monte Carlo simulations were employed to determine the loading of 5-FU in both ZIF compounds under different thermodynamic conditions and over a wide range of pressures, where it is revealed that the loading for the modified ZIF (2311 mgr/gr) is four times higher than the loading for ZIF-8 (560 mgr/gr). Moreover, Molecular Dynamics simulations offer a detailed comparison between the two ZIF materials in aqueous systems and provide deeper insight into their drug-material interactions.
04 Οκτωβρίου 2024
Δείτε το σύνδεσμο.02 Οκτωβρίου 2024
English text follows.
Την Πέμπτη 3 Οκτωβρίου και ώρα 9:00, θα πραγματοποιηθεί το Σεμινάριο Ασφαλείας του Τμήματος στην αίθουσα Φ2 του κτηρίου Φυσικής. Η παρακολούθησή του είναι υποχρεωτική προκειμένου να μπορέσει κάποιος να παρακολουθήσει κάποιο Εργαστηριακό Μάθημα. Θα τηρηθεί παρουσιολόγιο. Οι φοιτητές που το έχουν ήδη παρακολουθήσει στο παρελθόν δεν υποχρεούνται να το παρακολουθήσουν ξανά.
On Thursday, October 3rd, at 10:00 AM, the Department's Safety Seminar will take place in room F2 of the Physics building. All master's and doctoral students who have not attended it as undergraduates must participate. Attendance will be taken.
The seminar is POSTPONED and will be rescheduled.