Biography:

Abstract:

Optical fiber gratings have gone through an improved growth of development in the current years in track with the observation of narrow-band reflection in the photosensitive core region of silica optical fiber which is Germanium or boron-doped. Fiber Bragg grating is a periodic modulation of the refractive index along with the core of a photosensitive fiber. The refractive index changes are made by exposing the fiber to the interference pattern of Ultraviolet light. FBGs are less sensitive to refractive index (RI) variations of the external medium as the fiber is covered by cladding, limiting the application of FBGs being used in biological and chemical sensing applications. The surface of the e-FBG is modified with functionalized coatings based on the target to detect the change in RI using different coating techniques and different nanomaterials such as AgNP, AuNP, etc., and is characterized. This sensing probe can be used in different biological sensing applications.

Keywords: Fiber Bragg grating, coating techniques, nanoparticles, functionalization,

Biography:

Dr. Davood Fathi received a B.Sc. degree in the field of electronic engineering from Amirkabir University of Technology, Tehran, Iran, in 1990, and an M.Sc. degree in the field of biomedical engineering from Sharif University of Technology, Tehran, Iran, in 1994. After a couple of years working in the industry, he worked toward a Ph.D. degree between 2006-2009 in the field of nanotechnology with the Nanoelectronic Center of Excellence, Thin Film and Photonics Research Laboratory, School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran.
Dr. Fathi has joined in 2010 as a member of the faculty of the Department of Electrical and Computer Engineering, Tarbiat Modares University (TMU), Tehran, Iran.
He has been the reviewer for more than 20 international journals including IEEE, OSA, Elsevier, Springer, John Wiley, and so on.
His current research interests include Nanoelectronics; Nanotechnology; Nanophotonics and Optoelectronics; Nano-biotechnology; Nano-microfluidics; Biosensors; Solar Energy.
He is also the author or co-author of more than 85 scientific journal and conference papers in various fields of Nanoelectronics, Nanotechnology, and Photonics.
Dr. Fathi is currently an Associate Professor in his department.
He has supervised more than 40 M.Sc. students and 5 Ph.D. students. One Ph.D. student and 3 M.Sc. students are currently working on an interdisciplinary topic of oocyte evaluation based on the design and fabrication of nano-micro fluidic systems.
He has been selected as an invited or keynotes speaker for several international conferences such as CCET-2022, CCT-2022, Nanotechnology 2022, Microfluidics 2022, Material Chemistry 2022, and so on.

Abstract:

Oocyte development is largely dependent on its mechanical properties. Cell mechanics control the outcome of cell division. In recent years, various techniques such as micropipette aspiration (MPA) and optical tweezers are being used to measure the mechanical properties of membranes. The traditional MPA systems, however, have low throughputs and limited potential for automation and require bulky infrastructures. These methods have been used to investigate the mechanical characteristics of single cells including the elastic and viscoelastic properties, etc. In MPA methods, by applying a specific suction pressure, the cell aspirates into a micropipette. The amount of aspirated surface into the pipette is then recorded and measured using an electron microscope over time. During the aspiration, any leakage between the cell and the micropipette needle causes an error in the measurement of suction pressure. Due to the complexity of pressure measurement, the accuracy of the results largely depends on the skill of the user of the equipment. Furthermore, surface water evaporation and bubbles in the micropipette lead to errors in measuring the applied pressure. Although the aspiration force is applied to the entire oocyte volume, since the direction of the applied pressure is random, the average values for the measured mechanical characteristics of the entire cell are considered. On the other hand, these techniques are generally labor-intensive and time-consuming, typically involving a difficult process of manipulation.
Microfluidic channels have been developed in the past two decades for various biomedical applications, due to advantages such as real-time analysis, system integration, transparency for direct optical access, labor, precise control, lower cost, and reduced space. Furthermore, microfluidic channels can be integrated with other techniques and can enhance traditional cell analysis methods. Biological cell analysis and characterization can be performed based on the shape, size, and deformability of single cells in microfluidic chips. Various methods have been applied for microfluidic single-cell trapping including hydrodynamic trapping, dielectrophoresis trapping, chemical trapping, gel trapping, magnetic trapping, acoustic trapping, laser trapping, etc.
In this lecture, I present a new method for designing and manufacturing microfluidic channels in order to measure and evaluate the mechanical properties of mouse oocytes. The proposed process has the advantages of high accuracy and fast and easy operation. In our proposed technique, the oocytes are trapped in a specific channel, as shown in Fig. 1.
Although the designed and manufactured structure has microfluidic dimensions, in the design and analysis of the structure, knowledge and software environment in the field of nanotechnology and nanoelectronics have been used.

Biography:

Carmelina Spanò joins the University of Pisa as a researcher in the Department of Biology. She received a degree in Biological Sciences from the University of Pisa, cum laude, and the title of Ph.D. in Agricultural Biology. She has held many courses in plant physiology (Plant Biochemistry, Plant Biotechnology, Plant Physiology, Transgenesis in plants, and currently Strategies of resistance in plants). Her primary research interests have been in plant response to abiotic stressors in laboratory-controlled conditions, with a particular interest in studying oxidative stress and antioxidant response in plants under different physiological or stress conditions. In the last decade, her interest has turned to the study of the effects of nanomaterials on plants. In her free time, she practices tai chi and brisk walking, and reads many novels, especially detective stories; she is also fond of jazz music.

Abstract:

Plastics are used in many industrial sectors and in several everyday life products. The extensive use and the poor attention to their disposal and recycling are causing the production of massive amounts of waste, with possible global contamination of environmental matrices. As known, plastics are not biodegradable and remain in the environment for long periods undergoing aging processing with fragmentation into smaller pieces, up to micro (less than 5 mm) and nano (less than 100 nm) particles dimension, the smaller fractions being of specific concern. The possible entry of these particles into the food chain through plants represents a problem to deal with to improve food safety for humans and animals. To investigate the interactions between these particles and plants, we used a multidisciplinary approach in which seeds of the model crops Allium cepa L. and Oryza sativa L. were treated with different concentrations of polystyrene nano plastics (PS-NPS), chosen as model particles, as polystyrene is among the six more used plastics, widely diffused in all the terrestrial environments including agro-ecosystems. Under short-term conditions, phytotoxicity, genotoxicity, and cytotoxicity effects were assessed during germination and the early stages of seedling growth. Thanks to our integrated approach it was possible to highlight that PS-NPS can impair seed germination and seedling growth.  They can be taken up by the root and translocated to the above-ground part of seedlings, even entering inside cells, where their presence is associated with ultra structural damages and genotoxicity. A different concentration/localization of main oxidative stress markers has been recorded, along with the induction of an enzymatic antioxidant response. Our results suggest that damages detected could be due not only to changes in the production/diffusion of oxidative stress markers but also to a possible direct effect of PS-NPS, able to overcome plant cell barriers.  Further studies under long-term conditions, with a particular focus on the edible parts of the plant, will be useful to better clarify the impact on the environment and health of nano plastics, but their ability, even in short-term experiments, to enter inside crop plants, and possibly into the food chain is a matter of considerable concern.

Biography:

Onkani Shirley Priscilla studied Chemistry at the Vaal University of Technology, South Africa, and graduated with an MTech in 2020. She has joined Prof. Fanyana's research group at the Nanotechnology, Catalysis, and Organic Chemistry Laboratory since 2016. Currently pursuing a Ph.D. in inorganic chemistry and environmental focus on the removal of emerging organic pollutants at the same institution and under the same supervision. She has so far published one research article in a peer-reviewed journal (J.Environ Manage). She has also mentored two undergraduate research projects and has four years of work experience in industry and academia.

Abstract:

Unregulated discharge of antibiotics has become a global concern for water pollution, of which Chloramphenicol known as an emerging pollutant is the pollutant study herein.  This work describes a comparative study of the degradation of chloramphenicol (CAP) in an aqueous solution using pristine and Ag-doped semiconductor photocatalysts obtained from TiO₂ and ZnO. Varying weight percentages (2.5, 5, and 7.5 wt. %) of Ag nanoparticles were doped on the semiconductor photocatalysts via the sol-gel method and then calcined at 500? for 3h. The pristine and Ag-doped semiconductor photocatalysts were characterized using UV-Vis, diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL), Fourier transform infrared spectroscopy (FTIR), and Scanning electron microscopy (SEM). These techniques confirmed the successful synthesis of the pristine and Ag-doped materials. The photocatalytic activities of all materials used for the degradation of CAP were carried out under LED visible light irradiation for 2h; and the effects of various operating parameters (such as doping agent Ag, catalyst loading, pH, and pollutant concentration) were also investigated. The result showed that enhanced CAP degradation in Ag-doped in comparison to the pristine materials was most suitable for CAP degradation, especially at low pollutant concentrations. The effect of pH on the CAP degradation was very versatile, depending on the catalyst introduced in the solution. Lower loadings of the photocatalysts were usually more effective for CAP degradation and the degradation trend in TiO₂ was 5 wt. % Ag doped > 7.5 wt. % Ag doped > 2.5 wt. % Ag doped > Pristine, while it was 2.5 wt. % Ag doped > 5 wt. % Ag doped > 7.5 wt. % Ag doped > Pristine in the ZnO.

Biography:

Monica Alexander-Sylvester is an American and Saudi-licenced general practitioner working at a private primary care center in Riyadh, Saudi Arabia. She is heavily involved in neuroscience research, specifically in the application of nanomedicine. The application of nanomedicine to the drug delivery of neurological diseases is one of her main interests. Currently, her focus is on the treatment of epilepsy using optogenetics. Optogenetics has several limitations that can be addressed with the promise of nanoparticles.

Abstract:

Optogenetics has revolutionized a new era of effective and targeted control over neural function. Combining both optics and genetics allows neurons to be controlled over specific spatial and temporal activity. However, it is limited since visible light cannot penetrate deeper brain structures. Upconversion nanoparticles (UCNPs) will up-convert lower-energy photons into one high-energy photon by absorbing the penetrable near-infrared (NIR) light and emitting wavelength-specific visible light, which will result in the manipulation of overexcited neurons. To overcome these limitations, we propose using a non-toxic nanocomposite (Fe3O4-PEG/rGO). Using the Fe3O4-PEG/rGO nanocomposite has the dual effect of delivering the NpHR Optogene and UCNPs to inhibit targeted excitatory neurons within the Temporal Lobe, consequently dampening seizures.