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The Survival Strategies Of Infectious Organisms Have Inspired Many Therapeutics Over The Years. Indeed, The Advent Of Oncolytic Viruses (OVs) Exploits The Uncontrolled Replication Of Cancer Cells For Production Of Their Progeny Resulting In A Cancer Targeting Treatment That Leaves Healthy Cells Unharmed. Their Success Against Inaccessible Tumours, However, Is Highly Variable Due To Inadequate Tumour Targeting Following Systemic Administration. Nanotechnology Is Paving The Way For New Carrier Systems Designed To Overcome This Challenge. Until Recently, A Biologically Derived Alternative To Metallic Particles, Namely Bacterial-derived Magnetosomes, Has Been Relatively Overlooked Presumably Due To The Challenges Associated With Their Biomanufacturer. They Possess Many Advantages Including A Narrow Size And Shape Distribution And A Biologically Compatible Surface Chemistry, Which Prevents Aggregation And Provides An Anchor For Functional Groups For Biotechnology Applications. Here We Demonstrated Their Nanocarrier Capabilities By Co-assembly With Herpes Simplex Virus-1 For The Treatment Of Mammary Carcinoma. This Provides A Magnetic Coat Of Armour For The Virus Shielding The Virus From Immune Attack In The Blood Stream. Magnetosomes Thus Enabled Tumour Targeting From The Circulation With Magnetic Guidance And Enhanced Viral Replication Within Tumours. This Approach Was Associated With A Significant Increase In The Recruitment/activation Of Cytotoxic T Cells And Reprograming Of The Tumour Microenvironment Towards A Pro-inflammatory Phenotype Resulting In Significant Tumour Shrinkage And Increased Survival In A Syngeneic Mouse Model Of Breast Cancer By 50%. Exploiting The Properties Of Such A Versatile Nanocarrier Offers An Exciting, Novel Approach For Active Tumour Targeting To Disseminated Neoplasms.
Munitta Muthana Is A Senior Lecturer In The Department Of Oncology & Metabolism. Her Research Focuses On Innate And Adaptive Immunity And Reprogramming The Tumour Microenvironment With Oncolytic Viruses. She Has A Long-standing Track Record Of Working With Viruses And She Devised A Way To Deliver Large Quantities Of Cancer-killing Virus To Tumours Using A Cell Delivery Approach. Together With Her Team (Nanobug Oncology Sheffield @ Nanobug_Shef) They Have Developed A Number Of New Nanodrug Delivery Platforms For Targeting These Viruses To Tumours Via The Bloodstream Using Nanomaterials Including Liposomes, Magnetic Nanoparticles, Nanohydrogels And Silk Fibroins. These Exciting Technologies Could Change The Way We Deliver Immunotherapies To Cancer Patients
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An Integrated Geophysical And Hydrochemical Study Of The Saline Paleo Water Uprising Into The Alluvial Aquifer Of The Oltrepò Pavese Plain Sector (Po Plain, Northern Italy) Is Presented. This Study Involved One-, Two- And Three Dimensional Electrical Geophysical Surveys, Hydrochemical Analysis Of Groundwater And Assessment Of Well Logs. Geophysical Surveys Specifically Involved Both Electromagnetic Surveys Undertaken Over Vast Areas For A Speedy Assessment Of Sub-vertical Conductive Bodies Connected To The Uprising Of High Salinity Waters Through Structural Discontinuities And More Detailed 1D To 3D Electric Resistivity Surveys For The Accurate Investigation Of The Sectors Where The Uprising Phenomenon Of Deep Saline Waters Occurs. The Studied Area Was Selected For Its Characteristic Hydrogeological Setting (Pilla Et Al., 2010; Torrese And Pilla, 2021). The Alluvial Aquifer Is Strongly Conditioned By The Presence Of A Buried Tectonic Discontinuity Along Which The Saline Waters Are Mainly Distributed. These Waters Rise Along The Discontinuities In The Bedrock And Flow Into The Overlying Alluvial Aquifer. This Particular Setting Conditions The Distribution Of Saline Waters Into The Alluvial Aquifer. Contamination From Saline Waters Is Not Spatially And Vertically Homogeneous Within The Aquifer. The Spatial Distribution Of Na–Cl Waters Suggests The Existence Of Plumes Of Highly Mineralized Waters That Locally Reach The Aquifer, Diffuse And Mix With Fresh Waters. Detailed 3D Imaging Revealed Irregular-shaped Shallow Saline Water Contaminations Within The Alluvial Aquifer. Deep Saline Paleo-waters Show A Dilution During Upward Migration. This Is Due To The Mixing With Shallow Fresh Groundwater. Highly Mineralized Groundwater Is Identified Even At Very Shallow Depth In Correspondence Of Each Plume, Which Is Located Above A Structural Discontinuity. On The Other Hand, There Is A Lower Degree Of Contamination In Those Sectors Of The Aquifer That Are Further Away From The Structural Discontinuities And Generally Only Involves The Deeper Parts Of The Aquifer. The Results From Our Study Are Applicable In Similar Hydrogeological Contexts Where The Aquifer's Contamination By Saline Water Is Caused By Mixing Of Freshwaters With Brines Or Where The Fossil Saltwater, Located Different Kilometers Far From The Coastline, Are Remainder Of Ancient Marine Ingressions.
Patrizio Torrese Is Assistant Professor In Applied Geophysics At University Of Pavia, Italy, Where He Carries Out Research And Teaching Activity. His Current Research Focuses On Near Surface Geophysics, Especially Hydrogeophysics, Archaeo-geophysics, Planetary Analogue Study, And Improvement And Development Of Shallow Geophysical Methods. He Participated In Research Projects Related To Groundwater Contamination, Circular Economy For Water And Energy, Sustainable Agriculture, Drought Resilience Improvement In Vineyard Ecosystems, Precision Viticulture, As Well As, Soil Seismic Characterisation, Seismic Hazard, Unstable Slope Characterization. He Was Training And Test Campaign Investigator And Experiment/instrument Safety Responsible For PANGAEA-X European Space Agency (ESA) Astronaut Training Campaigns. He Also Carried Out Consulting Activity In Civil Engineering And Water Research Projects. He Is Author Of More Than 50 Peer-reviewed Articles And Conference Papers.
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Magnesium alloys are the lightest of all practical alloys and have a great weight-reduction effect, thus they are expected to be applied to vehicle bodies. Recently, the development of a composite material (cladding plate) between magnesium alloys and aluminum alloys is drawing attention to achieve. Magnesium alloys and aluminum alloys are difficult-to-weld materials since the bonding strength is reduced by forming a brittle intermetallic compound layer at the bonding interface due to heat input during joining. In the present study, the explosive welding method, which is a type of solid-phase welding, is applied to the dissimilar joining of Mg/Al alloys. This method utilizes the instantaneous high energy generated by the explosion of explosives for metal bonding and has almost no thermal effect except for local heat generation near the bonding interface. Previously, it was revealed that a thin interlayer was formed at the interface in cladding plates produced by explosive welding between magnesium alloys having different aluminum concentrations and A6005C aluminum alloy. The thickness of the interlayer increased with an increase in aluminum concentration in the magnesium alloy, while the thickness was 1μm or less. Scope of this study is to clarify the effects of aluminum alloy compositions on the interfacial microstructure and mechanical properties of the cladding plates. In the AZ31/A6005C and AZ31/A5052 cladding plates, when the magnesium concentration in the aluminum alloy was high, the thickness of the interlayer increased, and the shear strength increased. Although the thickness of the interlayer is not uniform, the weldability might be improved as the thickness of the interlayer increases. In the AZ80/A6005C and AZ80/A5052 cladding plates, when the magnesium concentration in the aluminum alloy was high, the thickness of the interlayer became very large (5μm or more), and the shear strength decreased.
Mami Mihara-Narita received her PhD in engineering from Tokyo Institute of Technology, Japan, in 2017. From 2017, she was a researcher at UACJ corporation. In 2019, she joined the Department of Physical Science and Engineering at Nagoya Institute of Technology, as an Assistant Professor. She has received several academic awards as the first author including the Light Meatal Promising Graduate Award (JILM, 2014), the Best Poster Award (JIMM, 2014, and 2017), the Best Poster Award in ICAA-15 (2016), Light Metal Outstanding Female Award (JILM, 2019), the Encouragement Prize for Young Researcher (Nagoya Institute of technology, 2007). Her research focus is on improvement of the properties of light metals by microstructure controlling, dissimilar metal joining of light metals, and severe plastic deformation of aluminum alloys.
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As previous studies have mainly focused on the reward system and the corresponding brain regions, the relationship between brain morphology and excessive internet use (EIU) was not clear, and the purpose of the study was to investigate whether brain regions other than the reward system were associated with EIU. Data were acquired from 131 excessive internet users. Psychological measures included internet use, life quality, personality, mental illness symptoms, impulsivity, and thought suppression. The brain was scanned with 3T magnetic resonance imaging (MRI), and 6 types of brain morphological indexes were calculated. Lasso regression methods were used to select the predictors. Stepwise linear regression methods were used to build the models and verify the model. The variables remaining in the model were left precentral (curve), left superior temporal (surface area), right cuneus (folding index), right rostral anterior cingulate (folding index) and harm avoidance. The independent variable was the EIU score of the worst week in the past year. The study found that brain morphological indexes other than the reward system, including the left precentral (curve), the left superior temporal (surface area), the right cuneus (folding index) and the right rostral anterior cingulate (folding index), can predict the severity of EIU, suggesting extensive changes in the brain. The study conducted a whole-brain data analysis and concluded that the changes in certain brain regions were more predictive than the reward system and psychological measures or more important for EIU.
Li Wan graduated from Virginia Tech, USA, currently working at the Affiliated Psychological Hospital of Anhui Medical University, China. She has been engaged in research on cognitive psychology, mental disorders and neuromodulation. The current main research direction is the regulation of cognitive impairment and the treatment of mental illness by nondrug and nontraumatic interventions and probes its neuropsychological mechanisms in various ways. The Brain Diseases and Neuromodulation Research Center was established in 2021, and a series of basic and clinical studies related to EEG, near-infrared imaging, neuroimaging, transcranial electrical stimulation and magnetic stimulation were carried out with her team members.
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Design, build and test (‘DBT’) of artificial organisms represented a fascinating approach to deepen our understanding of natural biosystems and to facilitate engineering life for applications. The speaker is engaged in understanding life by engineering and functional analysis of the biological components that store or express the genetic information, and in recent years have made some significant achievements as below: 1) synthesis and functional analysis of the longest linear designer eukaryotic chromosome, namely yeast chromosome 12, which “was a significant milestone towards creation of the first fully synthetic eukaryotic genome”; 2) engineering and functional analysis of a series of artificial ribosomes, which uncovered the functions and mechanistic insights of ribosomal RNA and proteins in ribosome assembly, translation and evolution. In this talk, the speaker will present the design principles, approaches, and what could be learnt from the ‘DBT’ cycle of these artificial microorganisms.
Guanghou Zhao is an associated professor at Northwestern Polytechnical University. His research focuses on design, build and test of artificial microorganisms to further the understanding of life and to facilitate engineered life for applications. He has published these experimental results in top-rated journals, including Science, PNAS, Nucleic Acids Research, which were highlighted in special article or previews by Nature, Science, Nature Biotechnology et al, and selected as one of the “Ten Breakthrough in Chinese Science 2017”.
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The meniscus is the fibrocartilage tissue of the knee joint, which plays an important role in transmitting loads, shock absorption, maintaining joint stability and reducing contact stress. Meniscal injuries can be commonly treated with simple sutures, while meniscectomy is inevitably required for severe injuries. However, meniscectomy could disrupt the mechanical microenvironment of the knee joint, leading to articular cartilage degeneration and osteoarthritis (OA). Tissue engineering technology, as a strategy with diverse origins, customizable and tunable mechanical and biological properties, has emerged as a promising approach for the treatment of meniscal injuries represented by 3D printing. Notably, the heterogeneity of the meniscus, including anatomical structure, cellular phenotype, extracellular matrix (ECM), and biomechanical properties, is critical for the reconstruction of natural bio-function. Therefore, the construction of heterogeneous tissue-engineered meniscus has become a promising approach for meniscus substitution and regeneration. Hereby, we systematically summarized the heterogeneity of the meniscus and 3D printing strategies for tissue engineering anisotropic meniscus. Manufacturing techniques, biomaterial combinations, surface functionalization, growth factors, and bioreactors related to 3D printing strategies are highlighted, and future research directions are proposed.
Mingze Du is a doctor student from the Institute of Sports Medicine in Peking University. The objectives of his research are: 1. Heterogeneous tissue engineering meniscus construction; 2. Study on the function and preparation method of biological collagen membrane.
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Diamond has emerged as an attractive electrode material over the past decades owing to its exceptional electrochemical properties, including the wide potential window for water stability, low background current, excellent electrochemical stability and antifouling properties. In the case of conductive diamond electrode materials, particularly for boron-doped diamond (BDD), the fouling process can be significantly suppressed because of many factors, such as the weak adsorption of fouling molecules on the respective electrode surface or the potential generation of strong oxidants (e.g., hydroxyl radicals) to suppress the formation of biofilm via self-cleaning. The factors of surface chemistry (e.g., the concentration of boron dopants and surface termination), crystal orientation and surface topography play critical roles in the electrochemically relevant properties of BDD. Recent progress and achievements regarding diamond sensors and biosensors for biologically-related sensing applications, particularly on determining fouling agents, will be summarized, including diamond microelectrodes, BDD based microfluidic devices, and noninvasive wearable sensors. The challenges and future of diamonds for antifouling applications will be discussed. This work will also include environmental applications with respect to wastewater treatment.
Zejun Deng received his PhD (2020) from Institut Polytechnique de Paris under the supervision of Profs. Christophe Renault and Fouad and Maroun. After a one-year postdoc (Research Fellow) with Prof. Huilin Shao at the University of Singapore, he joined as a Lecturer in the Department of Materials Science & Engineering at Central South University. His current research interests include diamond electrochemistry and diamond-related applications in the field of electrochemical sensors and wastewater treatment. He has published over twenty peer-reviewed articles in international journals and featured as a young editorial board member in Functional Diamond.
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Deep full-thickness burn wounds are prone to multi-drug resistant (MDR) infections following injury, which extends the healing time. Thus, providing a bioactive hydrogel dressing with prolonged antimicrobial activity and reduced dressing changes is quite desirable for accelerating burn wound healing and preventing scarring. To achieve this, we developed an injectable hydrogel based on silk sericin (SS), poly (vinyl alcohol) (PVA), and PVA microspheres (MSs) containing vancomycin (VA), gentamicin (GEN), or their association (VG) for the healing of infected burn wounds. The microspheres were prepared by inverse emulsion crosslinking, while the hydrogels were prepared by freeze-thawing cycles. Antibacterial studies showed that gentamicin acts synergistically with vancomycin by increasing the bacterial killing rate and enhancing the biofilm inhibition and eradication effects on methicillin-resistant Staphylococcus aureus more than on Pseudomonas aeruginosa and Escherichia coli. Findings from SEM images showed that the microspheres were sphere-shaped with a smooth surface and their average diameter ranging from 26.22 to 32.42 μm suitable for parenteral drug delivery. The prepared hydrogel containing 10% of microspheres was more elastic than viscous, with lower tan delta values (<1) suited for deeper injection with homogeneous tissue integration. The incorporation of VG-PVAMS in the PVA/SS hydrogel led to zero-order release kinetics and efficient antimicrobial effects. Moreover, the in vivo study using a rat full-thickness burn model showed that the [email protected]/SS hydrogel displays a better therapeutic effect than drug free [email protected]/SS hydrogel and TegadermTM film dressing by inducing early vascularization and collagen deposition, leading to early re epithelialization and burn wound closure.
Bakadia Bianza Moise is currently a Ph.D. student at Huazhong University of Science and Technology and a research fellow at the Higher Institute of Medical Techniques of Lubumbashi, DR. Congo. He received a Bachelor of Science degree from the Higher Institute of Medical Techniques of Lubumbashi, DR. Congo, and a Master's degree from Huazhong University of Science and Technology, China. His research interests include biomedical analysis of biological fluids, the immune response to microorganisms, and the development of biomaterials for tissue engineering. He has published more than 19 SCI papers.
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Micro/nanoscale heat conduction is crucial for a broad range of applications such as thermal management of electronic devices, thermal insulation, and thermoelectrics. Understanding and designing of thermal transport properties in solid materials largely depends on atomistic simulations based on density functional theory (DFT) or empirical potentials, which however suffer either low computational efficiency or accuracy. In recent years, machine learning is emerging as a powerful tool to bridge the gap between DFT and empirical simulations. The applications of machine learning in exploring thermal transport properties of solids mainly include constructing interatomic potentials and predicting thermophysical properties of materials. In this talk, we will introduce our recent progess in building machine learning interatomic potentials and predicting interfacial thermal resistance using machine learning. On one hand, we have developed machine learning interatomic potentials that can accurately describe phonon transport in materials containing point defect, grain boundary structures, and layered materials. The machine learning interatomic potentials achieve DFT-level accuracy and 3 to 5 orders of magnitude higher efficiency than DFT. On the other hand, we have developed machine learning models to accurately predict the thermal resistance of non-metallic/non metallic and metal/non-metallic interfaces.
Ruiqiang Guo is a professor at Shandong Institute of Advanced Technology. He received his B.S. in from Jilin University in Materials Science and Engineering in 2008, his M.S. in Materials Science from Huazhong University of Science and Technology in 2011 and his Ph.D. in Mechanical Engineering at the Hong Kong University of Science and Technology in 2015. After that, he worked as a postdoc at the Hong Kong University of Science and Technology, California Institute of Technology, and University of Pittsburgh. His main research interest is in nanoscale heat transfer and energy conversion, with special focus on the fundamental understanding of transport and interaction processes of principle energy carriers, as well as the design and engineering of materials for thermal management, electronics and clean energy.
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Vectorization of viruses provides the approach of the exploitation of the remarkable viral capabilities of delivering genetic material to host cells. Recently, gene therapy (GT) based on viral vector has emerged as a promising therapeutic modality for multiple inherited and acquired human diseases. Following just a single application, GT is capable of achieving curative treatment or mediating long-lasting therapeutic benefits, which fundamentally distinguishes itself from traditional medicine. For the last four decades, retrovirus mediated gene therapy has been the major player in the field of GT, and multiple lentiviral/ γ-retroviral vector-mediated GT products have been approved for treating various pathological conditions, including immunodeficiency, blood disorders and neurometabolic disorders. However, the early development of GT had been turbulent, with unexpected devastating effects exposed linked to the genotoxicities associated with retroviral semi-random genomic insertion. Here we talk about how the iterative vectorization processes taming the retroviruses, enabling them to become the foundation of modern gene therapy. And we will also take an evolutionary perspective to understand and perceive how retroviruses shaped us in the distant past.
Xiaomo Wu is the head of Regenerative Medicine LAB and the deputy Director of the Dermatology Institute of Fuzhou, China. She received a B.A. in Medicine in 2002 from the University of Wuhan, followed by a M.S. in Genetics in 2006 from the University of Fudan, Shanghai. In 2008, she came to Biozentrum, the University of Basel, Switzerland and received a PhD in Genetics in 2012 under Prof. Walter J. Gehring. She conducted her postdoctoral research in Bettler’s LAB, Biomedicine Department, also from the University of Basel, Switzerland. In 2017, she was recruited as a lad head and the deputy director of a newly founded institute in the Dermatology Hospital of Fuzhou, Fujian, China. In recent years, her Lab has been dedicated to developing therapeutic interventions based on genetic modification and alteration, namely gene therapy, for the treatment of inherited skin diseases as well as hemophilia A.
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In chemical industry, the chemical engineering community is already paying significant attention to the quest for technologies that would lead us to the goal of technological sustainability. In this context, improved membrane material has come a long way over the past three decades from a simple laboratory curiosity to full-fledged commercial environmentally friendly technology to answer the multifarious demands of chemical industry. Also, newly developed HF membrane contactors with super hydrophobic membrane have proved to be efficient contacting devices, due to their improved hydrophobicity and high area per unit volume that results in high mass transfer rates. Membrane contactor processes, in which phase contacting is performed or facilitated by the structure and shape of the porous membrane, provide a new dimension to the growth of membrane science and technology and also satisfy the requirements for process intensification. Some of the specific examples of HF technology are as follows: gas-liquid applications including oxygen desorption for industrial scale boilers, from ultrapure water, for absorption applications and at smaller scale, for blood oxygenation in open heart surgery. Recent progresses include selection of better contactor membrane materials and/ or modification of existing membranes via coating/surface modification or development of an altogether new material or membrane structure. High free volume polymer-based dense coatings with high gas permeabilities can eliminate membrane pore wetting caused by various absorbents. A number of examples of ILMs for gas separation show extended stability. Membranes with greater solvent resistance have appeared for membrane contactors for L-L processes. Prevention of loss of organic solvent-extractant acting as a SLM continues to be challenging. Introduction of fiber sorbents has facilitated applications of gas-solid membrane contactors. Porous hollow fiber membranes facilitate high efficiency mixing of anti-solvent with a crystallizing solution to enable continuous processes for crystallization as well as forming a polymer coating on suspended crystals and nanoparticles. This invited talk presents the overview of HF technology and their commercial applications in chemical industries including current scenario of these techniques applied worldwide. Attempts are made to focus future progresses in membrane engineering.
Anil Kumar Pabby was serving Bhabha Atomic Research Centre (BARC), Tarapur, Mumbai, Maharashtra, as Senior Scientist (Scientific Officer, G). Now, he is retired on superannuation in July 2021. He did his Ph.D. from University of Mumbai, India and subsequently carried out his postdoctoral work at Technical university of Catalunya, Barcelona, Spain. He has more than 190 publications to his credit including 20 chapters and two patent on non-dispersive membrane technology. He has taken a leading role in publishing “Handbook of membrane separation: Chemical, pharmaceutical, food and biotechnological applications’ in July 2008 and second edition published in April 2015. Also, he has been awarded with prestigious Tarun Datta Memorial award (instituted by Indian Association Nuclear Chemist and Allied Scientist) in 2005 for his excellent contribution in Nuclear and Radiochemistry. He is serving as Editor/editorial/advisory board member of some international peer reviewed journals (Separation and Purification Reviews, Desalination (2010-2014), Desalination and Water Treatment, Membrane Technology, Applied Membrane Science and Technology, Journal of Radioanalytical & Nuclear Chemistry (Editor 2001-2005).
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Nanoparticles draw larger attention in the latest years due to their versatile chemical, optical, electrical and magnetic properties. The metal oxide nanoparticles i.e zinc oxide, copper oxide, and titanium dioxide showed potential applications as photocatalyst, sensors and luminescent material for optoelectronic devices. The properties of such metal oxide nanoparticles are size and shape dependent. The synthesis route i.e chemical or green, selection of precursor, stabilizing material and operating temperature conditions affects the morphology of synthesized nanoparticles. To remove pollutants i.e dyes from industrial water, the different semiconductor metal oxide nanoparticles having particular size and shape tested for their photocatalytic behaviour. The chemical synthesis route i.e co-precipitation method using the Zinc acetate dihydrate, Sodium hydroxide, and Cetyltrimethylammonium bromide as precursor, reducing and stabilizing agent respectively produced elongated triangular bipyramidal shaped zinc oxide nanostructures and the fructose capped zinc oxide nanoparticles synthesized via co precipitation method elaborates the formation of quasi-spherical shaped nanoparticles. The synthesized zinc oxide nanoparticles showed good photocatalytic activity for removal of methylene blue and congo red dyes. The green synthesis route preparing extract from the plant leaves i.e syzygium cumini gives formation to spherical shaped zinc oxide nanoparticles. The synthesized nanoparticles used for removal of reactive orange-4 dye in photocatalytic process. The green synthesis is preferred process due to its environment friendly nature and cost effectiveness. This review elaborates the synthesis of zinc oxide nanoparticles through chemical and green synthesis routes and use of synthesized nanoparticles for removal of pollutants i.e methylene blue, congo red and reactive orange-4 dyes from water for environment remediation.
Gurjinder Singh has research area in the field of synthesis, characterization and electronic properties of metal oxide semiconductor nanoparticles. His research work highlights the synthesis of copper oxide, zinc oxide and titanium dioxide semiconductor nanoparticles through chemical and green synthesis methods. He has published research articles having Photocatalytic applications of nanoparticles. His current research work relates to the properties of metal oxide semiconductor nanoparticles i.e. Light absorption, photocatalytic, photoluminescence, anti-reflective and electrical resistivity for optoelectronic devices.
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Dynamic and intense research is being carried out on magnetite nanoparticles because of the vast potential of their usage in various fields such as biomedicine, drug delivery, resonance imaging, making transformers cores, microwave devices, recording material, etc. Various properties of magnetite can be easily optimized by doping with various metal ions. The rare-earth ions have unpaired 4f electrons and strong spin orbit coupling of angular momentum due to which they have higher magnetic moments. In this study, an overview is presented to investigate the effect of rare earth doping in magnetite. The effect of doping on the structural, morphological, magnetic, optical, and electrical behavior of magnetite has been discussed for various applications.
Richa Jain has completed her Ph.D. in Nano Science in the year 2021 from IGNOU. Her area of research interest is synthesis and characterization of ferrites nanomaterials. She has a teaching experience of more than 12 years and is currently employed as an assistant professor in a college under the central University of India (University of Delhi) India.
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This paper addresses machines, automated guided vehicles (AGVs), tool transporter (TT), and tools concurrent scheduling in a multi-machine flexible manufacturing system (FMS) for makespan minimization. The fewest copies of each tool type are employed to prevent tool delays, and job and tool shift times between machines are taken into account. The tools are placed in a central tool magazine (CTM), which shares and serves them to many machines to cut down the price of duplicating the tools in each machine. This simultaneous scheduling problem is challenging to solve because it entails determining the fewest tool copies of each tool kind without tool delay, assigning AGVs and tool copies to job-operations (jb-ons), ordering jb-ons on machines, and related trip operations such as deadheading and loaded flight times for both TT and AGVs. This paper uses a mixed-integer nonlinear programming (MINLP) framework to present the problem, and a flower pollination algorithm (FPA) is employed to solve it. For verification, a manufacturing company's industrial problem is employed. The results show that employing two copies each for two tool types and one copy each for the remaining tool types causes no tool delay, reduction in makespan and cost, and the FPA outperforms the Jaya algorithm.
N Sivarami Reddy completed his Ph.D. at JNTUA, India, in 2019. Currently, he is working as a Professor of Mechanical Engineering. He has 30 papers to his credit. His research areas include the Scheduling of FMS and Soft Computing Techniques.
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A gas sensing system for the detection of harmful and hazardous ammonia gas is made using a Surface Plasmon Resonance (SPR) laboratory setup. In this manuscript, various methods for producing developed ZnO, SnO2 and traditional WO3 and In2O3 nanowires on a large scale and with great reproducibility have been discussed. The NH3 gas-sensing system that was proposed for our developed ZnO and SnO2 performed better than expected. The ZnO/PPy and SnO2/PPy interface is used to successfully demonstrate the SPR system for the detection of NH3 gas. But for NO2 gas applications, the traditional WO3 and In2O3 nanowires technologies are primarily utilized. In order to successfully detect NH3 gas, thin films of 100 nm ZnO and 150 nm PPy were formed, which provide the sharpest SPR reflectance curve. SnO2 performed better when compared to other approaches. The SPR gas sensor exhibits a rapid response (1 s) and good sensitivity (3.15x10-3 o/ppm) for ZnO and (4.5x10-3°/ppm) for SnO2 towards NH3 gas over a wide concentration range (1 to 10 ppm). Additionally, the dynamic response was seen, and from the calibration curve, the sensitivity was calculated to be 0.202 /ppm for SnO2 and 0.121 /ppm for ZnO, respectively. Because of improved response characteristics, the research demonstrates that efficient SPR gas sensors are accomplished in the current SnO2 with PPy work.
Ajay Pratap Singh Gahlot received his B.Sc. Physics (Hons) from Dyal Singh College, University of Delhi and M.Sc. degree in physics from the University of Delhi, New Delhi, India. Currently, he is working as Associate Professor, Department of Physics, Deshbandhu College, University of Delhi. His research interests are in the area of Condensed Matter physics, High temperature Superconductivity, Perovskite Solar Cell and the Study of Nanostructures based design of devices for gas sensing application. Presently, working on SnO2/ZnO /Polypyrrole Composite Nanomaterials and its various properties and applications. He has vast experience of teaching at different colleges. He is the life member of Math Tech Thinking Foundation: Fazilka, Punjab, India, Also, an affiliate member of Royal Society of Chemistry and American Chemical Society. Have experience of organizing several national & international conferences and seminars.
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Here, we are investigating the effect of composition on the Oxygen Evolution Reaction (OER) mechanism of Sm2- xSrxNiO4-δ (x = 0.4 to 1.0 with a step of 0.2) synthesized through the standard solid-state technique. With the change in oxygen non stoichiometry, Rietveld refinement of X-ray diffractograms and EDX indicate the compositional phase change from orthorhombic to tetragonal. x = 0.6 and 1.0 thin films were also produced using the Pulsed laser deposition technology (PLD) for comparative electrocatalytic behaviour understanding, and cyclic voltammograms were compared to bulk ones to estimate the transient response and electrochemical reversibility. The cyclic voltammetric curves in bulk samples indicate a change in the number of electron transfers with x, as well as a change in electrochemical reversibility. Our findings show that electrochemical reversibility in thin films is driven by adsorption rather than diffusion, as it is in bulk samples. In both bulk and thin films, we found that the tetragonal phase (x= 1.0) has a larger Tafel slope than the orthorhombic phase (x = 0.6).
Manisha Chauhan is a senior research fellow at the Indian Institute of Technology (BHU), working under Prof. Prabhakar Singh's supervision in the department of physics. Functional materials for energy application, fuel cells, and electrochemical energy devices are my areas of interest. She is currently working on Investigation of Nickelate-based Ruddlesden popper perovskites for fuel cell applications. She has published a couple of papers in prominent journals that look into the catalytic characteristics of the RP system and double perovskite system. And a few papers are in the process of being communicated.
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Magnesium is an alkaline earth light metal with good biocompatibility and osteoconductivity. It is one of the essential minerals for the human body. However, pure magnesium is not suitable for artificial biomaterials since its low mechanical properties and corrosion resistance. Composites of magnesium and its alloys with bioceramics have been developed to enhance desired properties. In this work, magnesium alloy (AZ31) and hydroxyapatite (HA) composites were fabricated using microwave energy of 2.45 GHz at 1.4 kW microwave power for 15 min exposure time in argon atmosphere. Biodegradable metal matrix composites (BMMCs) of three compositions; AZ31 with 10, 15 and 20 wt% hydroxyapatite, were explored. The role of nano-hydroxyapatite in microwave heating of BMMCs was analyzed and observed that heating rate increased as HA content increased in the BMMCs. It happened due to the higher dielectric loss of HA than AZ31. The high dielectric loss enhanced the microwave absorption in the green compact of BMMCs and raised the temperature at the same exposure time and microwave power. Microwave heating mechanism of BMMCs was also tried to understand. Moreover, these three BMMCs were characterized for their microstructural, mechanical properties and corrosion behaviour. The XRD and SEM results revealed that the major phases are Mg and HA, while in AZ31/20HA, one minor phase of the β-Ca3(PO4)2 is observed. AZ31/20HA showed the highest density and microhardness among the three compositions. In contrast, AZ31/15HA exhibited the highest compressive strength, Young's modulus and corrosion resistance. The reason for reducing AZ31/20HA compressive strength is the formation of the β-Ca3(PO4)2 phase since it shows lesser compressive strength than HA phase, which reduces the compressive strength of BMMC. Similarly, β-TCP degrades faster than HA due to its high solubility in simulated body fluid, which reduces the corrosion resistance of AZ31/20HA. However, the noble achievement of this study is the porosity gradient developed in the microwave processed BMMCs. The porosity gradient was obtained due to specific microwave heating characteristics; material gets heated from core to surface. Porosity gradient could be the desirable attribute of BMMCs for orthopedic applications. It enhances the osteogenesis reactions, increases surface area for more ion exchange from artificial material to host tissue and helps in tissue in growth.
Shivani Gupta is a Senior Research Fellow at Indian Institute of Technology Roorkee, India and she is going to finish her Doctor of Philosophy. She has done her B.Tech with honor and was awarded Gold Medal in her Master's. She visited The Pennsylvania State University, USA, as an Exchange Visiting Scholar under SPARC scheme. Her research areas are manufacturing processes, process optimization, powder metallurgy, microwave materials processing, biomaterials, characterization, modeling and simulation.
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Micropropagation techniques are commonly used to produce large quantities of healthy plants in commercial agriculture. In this technique, all plant parts used in vitro experiments should be free of microorganisms. Therefore, vigorous surface sterilization is carried out. Chemical sterilization based on HgCl2, NaOCl, alcohol, benzalkonium chloride and peroxide (H2O2) are commonly used at commercial scale and some of these compounds are known to be highly carcinogenic and toxic. Therefore, these practices, impose threats to both humans and the environment. Photocatalytic sterilization is identified as a safer and sustainable alternative method. In this study, an efficient photocatalytic nanohybrid material based on Ag decorated iron titanate (Ag-FeTiO3) derived from natural beach sand has been developed. FeTiO3 nanoparticles are isolated from beach sand using an acid dissolution method followed by treatment with AgNO3. Electron microscopy studies confirmed the successful anchoring of Ag nanoparticles onto the iron titanate nanoparticles separated from beach sand. The band gap of 2.80 eV calculated using UV-Vis studies confirmed its activity under visible light. The efficacy of the nanohybrid has been tested using Scindapsus aureus as the model plant. Plant nodes (40 for each experiment) were sterilized using commercial sterilizing agent 10% Clorox at 360 Lux (N1) and Ag-FeTiO3 dispersion and kept the plants under various light intensities of 290 Lux (N2), 360 Lux (N3) and 30,000 Lux (N4). Rate of contamination and propagation of the plants were monitored for a period of 90 days. It was observed that 63%, 54%, 16% and 20% contaminations were observed for Ni, N2, N3 and N4, respectively. Interestingly, high rate of node propagation (84%) was observed in the plants sterilized using nanohybrid under 360 Lux value (visible light) compared to N1 (37%). The observations confirm significantly improved sterilization efficacy in removal of microorganisms thus leading to improved rate of propagation.
Nethupa is a high school student in Bellaire high school Houston Texas, USA. The research was conducted in Sri Lanka while studying in Gateway College Colombo, Sri Lanka.
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Organic molecules, known as dyes, which can absorb and emit light, have various potential applications, such as biomedical imaging, organic photovoltaics, non-linear optics, and quantum information systems. These applications are controlled by dye orientation and properties such as extinction coefficient, transition dipole moment, and aggregation ability. Dye aggregate networks via deoxyribonucleic acid (DNA) templating exhibit exciton delocalization, energy transport, and fluorescence emission. DNA nanotechnology provides scaffolding upon which dyes attach in an aqueous environment. To control the process and optimize the properties, a combination of machine learning, density functional theory (DFT), and time-dependent (TD) DFT was performed to screen more than 26,000 dyes, select ideal dye candidates, and determine dye structure-property relationships. The machine learning models were developed with an accuracy of above 90%. Top 15 dyes were identified due to their properties comparable to those of a reference dye - pentamethine indocyanine dye Cy5. Molecular dynamic (MD) simulations were then performed to reveal dye aggregate-DNA interactions and dye orientations. Simulation results agreed well with experimental observations. The developed data-driven and computational workflow for identifying dyes with large extinction coefficients and transition dipole moments and good aggregation ability is effective and can be used as a tool to develop new dyes for excitonic applications.
Lan Li is an Associate Professor at the Micron School of Materials Science and Engineering, Boise State University in Boise, Idaho, USA. She leads the Materials Theory and Modeling Group, focusing on the development of multiscale modeling and data-driven approaches to design materials for electronic and energy applications. She has received research grants from Department of Energy, National Science Foundation, Office of Naval Research, Idaho National Laboratory, and National Institute of Standards and Technology. She has also been awarded the CAES (Center for Advanced Energy Studies) Follow, Boise State University’s Top Ten Scholar Honored Faculty, TMS (The Minerals, Metal and Materials Society) Young Leader Professional Development Award, and NIST (National Institute of Standards and Technology) – ARRA (American Recovery and Reinvestment Act) Fellowship. She has been a former Chair of TMS Education Committee, and presently serves as a Programming Chair for TMS ICME (Integrated Computational Materials Engineering) Committee.
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The cleaning practices of U.S. wildland firefighters' personal protective clothing (PPC) are widely unregulated and unknown. As documented in the structural fire service, failure to regularly and effectively clean soiled and contaminated PPC may lead to severe health impacts, especially in the long term. This study aimed to investigate the current cleaning practices of wildland firefighting gear and to determine the laundering resources wildland firefighters have access to while deployed in the field. This study is the first of its kind to collect end-user feedback on wildland firefighter PPC cleaning. Findings indicate most wildland firefighters do not isolate their contaminated gear, wash their PPC at home, and frequently transport their gear in personal vehicles. These practices are significant departures from the recommendations of the National Fire Protection Association 1877 Standard on Selection, Care, and Maintenance of Wildland Firefighting Protective Clothing and Equipment. Considerations of practicality and feasibility specific to the wildland fire service should be adopted by the standard.
Meredith McQuerry is an Associate Professor of Textile Science in the Jim Moran College of Entrepreneurship at Florida State University. She oversees the operations of two labs; the Textile Testing Laboratory and the ThermaNOLE Comfort Lab® home to the only dynamic sweating thermal manikin at a public institution in the western hemisphere. As a clothing comfort physiologist, her research focuses primarily on the physiological comfort and performance of protective clothing for first responders, athletes, and industrial workers.
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The idea of flexible body armor is not new, and it has been around for the last few decades. What is, however, new is how it has evolved to its current state. Initial development included shear thickening fluid (STF) as a backbone polymer to impregnate ballistic fibers. STF was made from a mixture of silica particles and polyethylene glycol (PEG) at 55 to 45% weight ratio. At the core of the spike and ballistic resistance was the instantaneous rise in viscosity of STF at the event of an impact. Viscosity rise was due to hydroclustering of fumed silica particles embedded within the PEG. When the armor system was dry, hydroclustering was not possible in absence of any fluidity in the polymer. Still, coating of silica particles around the fiber offered reasonable amount of resistance to spike and ballistic penetration. In the next step, when silica nanoparticles were functionalized with a silane coupling agent (Gelest), siloxane (Si-O Si) bonds were formed and it improved bonding of particles to the fiber. Subsequently, PEG was replaced by silane as the base polymer to develop N-H (amide) receptors on the surface of silica particles. To promote further bonding, a fixative cross-linker, Glutaraldehyde (Gluta) was added in the particle-polymer mixture. Gluta created strong bridges between distant pair of amide groups present in silated silica particles and kevlar. The particle-polymer mix was then used to impregnate multiple layers of woven kevlar fabrics to construct the armor. After fabrication, armor composites were tested using a drop tower following the NIJ (National Institute of Justice) Standard 0115.0.NIJ tests were performed with spikes having a drop weight of 1790g and drop heights ranging from 0.05m to 1.0m. that produced impact energies from 1 to 18J. Impact energy is normalized with aerial density of the armor to account for any variation in layer thickness during impregnation. It is observed that spike resistance for no penetration (i.e., 0 witness layer) increased from 12 J-cm2/g for STF to 200 J-cm2/g for the new silane-silica-gluta system. The improvement is almost 16 times. Silica nanoparticles bonded strongly with kevlar in uniform dispersion and offered unprecedented resistance to penetration.
Hassan Mahfuz is a Professor in the Ocean and Mechanical Engineering Department at Florida Atlantic University (FAU). He is also the Director of Nanocomposites Laboratory at FAU. He has published 11 book chapters, 111 journal, and 146 conference papers in composites and nanostructured materials. He has 1 US patent. He has presented 48 keynote and invited lectures in 13 countries. He has served as PI and Co-PI in materials research funding totaling $30 million in 56 projects since 1990. He has graduated 12 Ph.D. and 48 M.S. students. He is currently supervising 2 Ph.D. and 2 M.S. students. He became a ASME Fellow in 2010. He is serving as an Editorial Board Member for Oceans Journal since 2020.
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The microstructures developed by the addition of (a) Ag and (b) Si in Al-Cu-Ni-Mn HEA alloy have been compared. The alloys were prepared by melting pure metals of at least 3 nines purity in electric arc furnace followed by casting. The alloys were repeatedly melted and cast several times to ensure a homogeneous distribution of the metals in the castings. The as cast microstructures in the monolithic form and as modified by Si and Ag were examined by the SEM in the back scattered electron mode. EDS was used to identify the compositions of the phases and x-ray color mapping was used to determine the locations of different elements in the microstructures. Phases developed, as identified by the compositions in atomic percent, were compared to ascertain the role of additives in the monolithic form. Monolith microstructure consists of three phases rich in (a) Al-Cu-Ni with gray contrast, (b) Ni with white contrast, and (c) Mn with black contrasts. Ag and Si alloys show similar three phases but variations in contrast. Phases in Ag alloy are rich in (a) Al-Cu-Mn, gray, (b) Ni, black, and (c) Ag, white, while the phases present in Si alloy are rich in the following elements: (a) Al Cu-Mn, gray, (b) Ni, white, and (c) Mn, black contrasts. The compositions of the phases in the alloys may also be related to the atomic radii of the elements in the phases. The ratio of the two richest elements in the phases show that if their atomic radii are within ±15% of each other then they attract other elements also in that phase. On the other hand, for ratios of the atomic radii for the two richest elements that are not within ±15%, other elements are not attracted towards this phase.
S.K. Varma is a professor in the department of Metallurgical, Materials, and Biomedical Engineering at the University of Texas at El Paso since 1984. He teaches Nanofunctional Physical Metallurgy, Mechanical Behavior of Materials at this time. He has taught many courses both at graduate and undergraduate levels. He is the recipient of many awards including Best Teaching and Distinguished Achievement in Research. He has been conducting research in many physical and mechanical metallurgy areas: large strain plastic deformations, static annealing, composite materials, corrosive wear, refractory metals, and high entropy alloys. The research has yielded nearly 100 peer reviewed journal publications, numerous proceedings papers and supervision of 35 graduate students for their master’s theses and Ph.D. dissertations. Organizers of the conferences, chairing many sessions in MS&T and TMS conferences, reviewing manuscripts for many peer reviewed journals are few of the other professional activities with which he is involved with.
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Introduction: The full potential of islet transplantation will only be realized by development of tolerogenic strategies that obviate the need for maintenance immunosuppressants. We are reporting a clinically relevant strategy that co transplantation of unmodified islets and SA-FasL-presenting immunomodulatory biomaterials achieved long term islets acceptance and glycemic control in the absence of chronic immunosuppression in an allogeneic diabetic non-human primate (NHP) model. Methods: Poly (ethylene glycol) [PEG]-based microgels presenting controlled densities of SA FasL are engineered. For experimental group, allogeneic unmodified islets from single donor were co-transplanted with SA-FasL-presenting microgels to the omentum of STZ-induced diabetic cynomolgus monkeys with Rapamycin as the only maintenance therapy for the first three months posttransplant. Recipients co transplanted islets with PEG microgels without SA-FasL served as controls. Animals were followed for six months to demonstrate that reproducible long-term grafts survival and tolerance can be achieved. Results: 4 experimental diabetic NHPs were co-transplanted with average 17K islet equivalents (IEQ)/Kg and SA-FasL-presenting microgel. Posttransplant each recipient promptly achieved excellent glycemic control with normal fasting BG during the 180- day designed study endpoint except one animal was electively terminated on day 147 posttransplant due to earlier grafts removal. IVGTTs performed at 3-month and 6-month post-transplant showed normal provocative glucose homeostasis, especially at the 6-month time point where blood glucose dynamics were as robust as the normal healthy animal. Insulin and C-peptide were greater than 1.5mU/L and 50pmol/L respectively for all animals. After removal of the islets containing omentum, all the experimental animals returned to diabetic immediately. All 4 recipients demonstrated evidence of Treg expansion and reduction of effector memory T cells by flow cytometry; and donor hypo-responsiveness by in vitro ELISPOT and MLR. 3 Control group diabetic NHPs that co transplanted islets with non-FasL presenting microgel in the omentum and Rapamycin as the maintenance therapy achieved glycemic control less than 3 weeks, which is consistent with similar IS regimens in the literature and our previous studies. Recipient demonstrated no evidence of Treg expansion and donor hypo responsiveness during study period. Conclusions: Immunomodulation with SA FasL-presenting microgels results in long term allogeneic islet graft survival in a NHP model in the absence of chronic immunosuppression. SA FasL-presenting microgels as an off-the-shelf product presents a novel immunomodulatory approach with considerable translational potential for the treatment of type 1 diabetes.
Ji Lei is an Associate Immunologist and the Director of the Human Islet/Cell Isolation and Transplantation Special Service cGMP Facility at Massachusetts General Hospital. He also holds an Assistant Professor of Surgery position at Harvard Medical School. As a surgeon, he was formally educated and trained in medicine, medical research, and business administration at 4 universities. He has over 30 years of clinic practice and research experiences with more than 70 research papers contributions. His research focuses are on immuno-tolerance induction, immune modulation, immune-isolation, and innovations of technologies in the fields of pancreatic islet transplantation to treat diabetes and hepatocyte transplantation to treat liver function failure. His core research expertise is in field of nonhuman primate translational studies for biomaterials such as encapsulation, immunomodulation, and novel cells derived from stem cells for the treatment of diabetes.
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The mechanical toughness in materials is defined as the amount of energy that a material can absorb per unit volume without experiencing a catastrophic failure. Despite the societal importance of tough engineering thermoplastics, it is currently not possible to predict why one material might display a tough mechanical response while another material might be brittle and breaks. In this work, we look at the origin behind mechanical toughness in a variety of polycarbonate-based systems in detail by Inelastic and Quasi-elastic Neutron Scattering (QENS) and were able to develop a framework that quickly correlates macroscopic mechanical toughness to the nanosecond dynamics. We find striking correlations between the fast relaxations in the quiescent glass and essential trends in mechanical toughness. The onset of macroscopic ductility (accompanied by a substantial increase in toughness), demarcated by the brittle-to-ductile transition (BDT), correlates with the onset of anharmonic motions in the mean-squared atomic displacement, (u2), on time scales faster than 1 ns. This finding1 emphasizes the role of anharmonic motions in dissipating energy in the glassy state. Poisson’s ratio, characterized by Brillouin light scattering, shows an upturn in the same temperature region. Further investigation2 into the full inelastic neutron scattering spectra reveals two nanoscopic processes: (1) collective vibrational modes (the so-called Boson peak) with a characteristic time scale τ ≈ 0.5–0.8 ps and (2) collective relaxations with τ ≈ 3 ps. We show that the macroscopic phenomenon of the BDT corresponds to a change in the dominant nanoscale process from vibration-dominated to relaxation-dominated dynamics. This work clearly shows relaxation processes are how tough materials dissipate the energy and shows a way forward to tune the mechanical toughness in polymer glasses.
Madhusudan Tyagi works at the National Institute of Standards and Technology (NIST) and the Department of Materials Science and Engineering at the University of Maryland. He has also been working as an instrument scientist for the High Flux Backscattering spectrometer (HFBS) for the last 15 years. His research interests include the dynamics and structure of liquids, polymers, and biomolecules.
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Surface Characteristics Play An Important Role In Identifying Surface Features And In Describing Stereometrics And Functional Properties. Characterization Of The Surface Is Possible On The Basis Of Test Results Obtained From Measuring Instruments. There Are Many Devices That Use Contact Or/and Non-contact Measurement Method. Each Device Can Be Used To Characterize The Surfaces. However, Not Every Device Is Suitable For All Materials, Type Of Surfaces Or Object Shapes. The Use Of Various Measuring Instruments Provides A Comprehensive Approach To Characterizing The Surface, Especially If The Devices Used Allow To Measure In Various Scales, From Macro To Nano. The Work Presents Advantages And Disadvantages Of Using Contact And Non Contact Measurement Method. The Various Measuring Instruments From The Macro To The Nano Scale Have Been Presented (i.e. Coordinate Measuring Machine, Optical Microscope, Focus Variation Optical System, Scanning Electron Microscope, Confocal Microscope, Interference Microscope, Contact Profilometer, Atomic Force Microscope) Used To The Surface Characterizing Including Identifying Surface Features, Describing Stereometrics And Functional Properties. On The Example Of Selected Materials (metals, Ceramics, Composites, Polymers), It Has Been Shown That An Important Step In The Methodology Of Surface Study (surface Characteristics) Is The Selection Of Measuring Instruments, Which Should Allow The Comprehensive Surface Analysis And Evaluation. The Quantitative (parametric) And Qualitative (non-parametric) Analysis Of The Research Results Was Presented. General Rules For Surface Characterizing Of Materials With The Use Of Various Measuring Instruments Have Been Defined.
Magdalena Niemczewska-Wójcik Has Experience On Faculty Of Mechanical Engineering At The Cracow University Of Technology: February 2006 – A Research And Teaching Assistant, October 2007 – A Research And Teaching Assistant Professor, From April 2019 – A Research And Teaching Associate Professor. Her Achievements Include The Functions, Such As - Vice Dean Of Faculty Of Mechanical Engineering At Cracow University Of Technology, Deputy Director Of The Institute, Member Of The University Senate, Member Of The Scientific Council Of Mechanical Engineering, Member Of The Polish Academy Of Sciences (Machine Building Committee), And The Research Internships, I.e. V. Bakul Institute For Superhard Materials NASU In Kiev (Ukraine), Tribology Department Of Łukasiewicz Research Network–The Institute For Sustainable Technologies In Radom (Poland) And NTB Interstate University Of Technology Buchs In Switzerland. She Is The Project Manager Of Regional Group Of Accredited Research And Calibration Laboratories Of The Cracow University Of Technology. Due To The Complexity Of Scientific Problems, Her Research Interest Includes: Materials And Biomaterials, Materials Properties, Manufacturing Process, Machining Process, Surface Engineering, Surface Metrology, Surface Topography, Methods Of Surface Topography Measurements (including Multi-sensors Instruments), Tribology/biotribology, Investigations Of Surface Topography (from Macro To Nano Scale), Tribology Studies (friction And Wear Tests), Surface Topography Analysis (including Multi-scale Analysis), Surface Characterization.
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Biodegradable materials with green shielding characteristics, where “green” represents large effective absorption and less secondary reflection are in great demand but up to date no attention has been given to fulfill both requirements. This requires meticulous microstructural design for independently controlling absorptionassociated polarization loss and reflection-associated conduction loss. Herein, 2D-layered MoS2 with low conductivity was integrated by simple soaking and carbonization into waste cellulose paper to promote both absorption through optimizing dielectric loss and green shielding through minimizing reflection. The 2D large surface area guaranteed efficient contact with the host and therefore only 10 wt% MoS2 resulted in higher but moderate conductivity than cellulose paper ensuring low reflection shielding effectiveness. Moreover, the cellulose fibers were bridged by MoS2 establishing a conductive network. Efficient conductive pathway and improvement of dielectric losses from interfacial polarization resulted in simultaneous EM absorption (~− 15 dB) and green shielding (28 dB, green shielding index gs ≈1). Therefore, the developed composites not only demonstrated environmental sustainability but also effectively suppressed secondary electromagnetic pollution.
Rabia Khatoon has recently completed her PhD in materials Physics and chemistry from Zhejiang university, China. She is working on the synthesis of heterostructure, waste-derived carbon based composites and their applications in energy devices, i.e. Li-ion, Li-S batteries, gas sensors and microwave absorbence with shielding effect. She has publish more than twenty articles.
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The development of a highly efficient methodology for establishing squeeze casting process parameters from past data is essential. However, designing squeeze casting process parameters based on past data is difficult when there are many missing values. Conventional missing data approaches are fraught with additional computational challenges when applied to highdimensional multivariable missing data, especially material process data with correlation. As the relationship between material composition and process parameters has similar characteristics with that between users and information of interest, we proposed a method for missing data imputation based on a clustering-based collaborative filtering (ClubCF) algorithm to address this challenge. Data samples with and without missing values were divided into two groups. K-means clustering based on a canopy algorithm was applied to the data samples without missing values to obtain k subclass data, whose values were then selected to fill data samples with missing values via a collaborative filtering theory based on Pearson similarity user filling. The missing squeeze casting process parameters data of aluminum alloys were used to evaluate the method, and more comparative experiments were carried out to understand their performance and features. Two different indicators, including the mean absolute error and the standard deviation, were utilized to quantify the imputation performance, which was compared with those of three conventional methods (mean interpolation, regression interpolation, and the expectation maximization algorithm). The results indicate that the proposed approach is effective and outperforms conventional methods in processing high-dimensional correlated data.
Jianxin Deng is currently working as a professor and a master supervisor of Mechanical Engineering at Guangxi University and the vice director of Guangxi Key Lab of Manufacturing System and Advanced Manufacturing Technology. He received his master degree in industrial engineering from Chongqing University (China) in 2004 and his Ph.D. degree in mechanical engineering from South China University of Technology (China) in 2010. His research interests include manufacturing systems and informatics, squeeze casting technology, E-manufacturing, product axiomatic design, manufacturing service technology.
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Titanium slag obtained from electric furnace smelting using ilmenite from Panzhihua contains predominately two phases: anosovite and augite. The mineral phase compositions in titanium slag can have severe effects on the leaching process and leaching efficiency. However, the precise role of the effect of mineral phases on the leaching efficiency is unclear. In this work, the leaching behaviour of titanium from slag originated from Panzhihua region was investigated by using kinetic analysis and the characterizations of mineral phases and morphologies of particles involved in the fluid solid leaching reactions. It was found that the leaching rates of titanium slag particles became more rapid with the increase of the concentration of sulphuric acid, temperature and surface area of titanium slag particles. Kinetic analysis using the data from the leaching kinetic study showed that the leaching process of titanium slag conformed to the shrinking core model controlled by surface chemical reaction and internal diffusion, and the apparent activation energy of leaching reaction was determined to be 69.87 kJ/mol. From the characterizations of mineral phases and morphologies of particles involved in the fluid-solid leaching reactions, it was shown that the formation of boundaries between mineral phases in titanium slag acted as resistance to slow down the leaching rate of titanium from titanium slag in sulphuric acid. Because the dissolution rate of augite phase was much slower than anosovite phase, the surface area available for the titanium leaching from titania-rich anosovite phase was reduced due to the coexistence of augite and anosovite phases in titanium slag particles. Our results demonstrate that the formation of boundary structures of anosovite and augite phases is an important factor affecting the leaching efficiency of titanium slag.
Xiaoping Wu has been working in Ansteel Research Institute of Vanadium & Titanium (Iron & Steele), Pangang Group, as a research director and a senior research fellow in the area of titanium fine chemicals, titanium extraction, and titanium oxide materials. Previously, he had worked as the senior research scientist and senior research engineer in chemical industries and universities in UK. He obtained a BSc and MSc in China, and a PhD in chemistry from University of London.
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Background and aims: It has been established that endothelial senescence plays a critical role in the development of atherosclerosis. Elevated S-adenosylhomocysteine (SAH) level induced by inhibition of S-adenosylhomocysteine hydrolase (SAHH) is one of the risk factors of atherosclerosis; however, the interplay between endothelial senescence and inhibition of SAHH is largely unknown. Methods: Human umbilical vein endothelial cells (HUVECs) after serial passage were used. SAHH-specific inhibitor adenosine dialdehyde (ADA) and SAHH siRNA treated HUVECs and SAHH+/-mice were used to investigate the effect of SAHH inhibition on endothelial senescence. Results: HUVECs exhibited distinct senescence morphology as HUVECs were passaged, together with a decrease in intracellular SAHH expression and an increase of intracellular SAH levels. SAHH inhibition by ADA or SAHH siRNA elevated SA β-gal activity, arrested proliferation, and increased the expression of p16, p21 and p53 in HUVECs and the aortas of mice. In addition, decreased expression of hTERT and reduced occupancy of H3K4me3 over the hTERT promoter region were observed following SAHH inhibition treatment. To further verify the role of hTERT in the endothelial senescence induced by SAHH inhibition, overexpression of hTERT plasmid vector under CMV promoter was constructed. The hTERT overexpression rescued the senescence phenotypes in endothelial cells induced by the SAHH inhibition. Conclusions: SAHH inhibition induces endothelial senescence via the downregulation of hTERT expression, which is associated with attenuated histone methylation over the hTERT promoter region.
Wenhua Ling is a professor of School of Public Health, Sun Yat-sen University, a doctoral supervisor, director of the Institute of Preventive Medicine, School of Public Health, Sun Yat-sen University, the director, key Laboratory of Nutrition, Diet and Health, Guangdong Province, a member of the 6th and 7th Disciplinary Review Group of the degrees Committee of the State Council, "National Distinguished Young Scholar" winner, the instructor of 100 excellent doctoral theses in China, and he is also an excellent teacher in China. He also published research papers as newsletter or the first author in international authoritative academic journals such as Circulation, Circ Res, Hepatology, JCI, Diabetes Care, Am J Clin Nutr, Heart,Clin Chem, ATVB, Cardiovasc Res, J Lipid Res, J Biol Chem, J Nutr., etc.
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The frequent emergence of variants of concern (VOC) of SARS-CoV-2 necessitates a sensitive and all-inclusive detection platform that remains viable despite the virus mutations. In this context, we targeted the receptor-binding domain (RBD) of glycoprotein (S-protein) of all VOC and constructed a consensus RBD (cRBD) based on the conserved amino acids. Then, we selected a high-affinity ssDNA novel aptamer specific for the cRBD by an in silico approach. The selected aptamer is utilized to fabricate a photonic crystal (PC)-decorated aptasensor (APC-sensor), which consists of polystyrene nanoparticles polymerized within a polyacrylamide hydrogel. cRBD-responsive ssDNA aptamers are crosslinked in the hydrogel network, which selectively bind to the cRBD and SARS-CoV-2 in saliva samples. The binding response can be visually monitored by swelling of the hydrogel and color generation by diffraction of light from PCs and can be quantified by the diffraction ring diameter or a spectrometer. The sensor delivers a LOD of 12.7 ± 0.55 ng mL−1 for the cRBD and 3 ± 18.8 cells mL−1 for SARS-CoV-2 in saliva samples, with a rapid response of 5 min. The sensor can be stored and regenerated without loss of activity. It can be utilized as a point-of-care testing (POCT) for SARS-CoV-2 diagnosis.
Ghulam Murtaza is a postdoctoral researcher at the School of Chemistry and Chemical Engineering, Beijing Institute of Technology, where he works on the photonic crystals platforms that can be used for the detection of biological markers. He obtained his Ph.D. from the Beijing Institute of Technology studying photonic crystal sensors and his interests include 2D photonic crystal sensors for the detection of viruses, bacteria, and biomarkers of significant diseases.
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Monolayers of micro- and nanoparticles on solid substrates have many practical applications. They include electrochemical, piezoelectric, and plasmonic sensors; catalysts; antimicrobial and antireflective surfaces; or substrates for spectroscopy. Once produced, the particle systems usually need to be tested to ensure their high quality and functionality. The main objective of our research has been to develop a cheap and accurate method for efficient characterization of particle films. We have demonstrated that the multidimensional function of static structure factor is a promising candidate for this purpose. To compute Its continuous, ensemble averaged approximation, we may Fourier transform the radial distribution function calculated over an appropriate range of interparticle distance and system parameters. To calculate a discrete approximation of the structure factor for a sample monolayer image, on the other hand, we need to compute the squared modulus of the discrete Fourier transform of the digital image. Then, performing a least-squares fit of the continuous approximation to the discrete data, we can estimate the system parameters, with no identification of individual particles. To validate our approach, we have first determined parameters of a dense array of monodisperse hard spheres, generated by event-driven molecular dynamics. The particle radius, surface coverage, and size of analyzed area have been found with standard errors on the order of 1%. Then, using images of monolayers published in the literature, we have demonstrated a practical application of the approach to determine important parameters of random particle ensembles at lower surface coverage. For that, we have used a 4D structure-factor function of the waive number, particle surface coverage, and diameter of analyzed area, computed for hard disk systems generated with the model of random sequential adsorption. Our results suggest that the novel approach can be generalized for films of charged particles by simply increasing the dimensionality of the structure-factor function.
Paweł Weroński studied Physics at the A. Mickiewicz University in Poznań, Poland, and graduated as MS in 1989. He then joined the research group of Prof. Adamczyk at the Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences (ICSC-PAS). He received his PhD and DSc degrees in 2000 and 2008, respectively, at the same institution. He earned two postdoctoral fellowships: at the Chemical Engineering Department of Yale University and at the Theoretical Division of Los Alamos National Laboratory. He works as an Associate Professor at the ICSC. He has published more than 50 research articles in SCI(E) journals.
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In the current study, aluminum matrix composites made of Al-Al9Co2-Al13Co4 are developed using powder metallurgy with a flow of N2 at a temperature of 600°C. In this study, the impacts of process variables such cobalt concentration (0.5, 1, 3, and 5%at.) and sintering time (4, 8, 24, 48, and 72 hours) on hardness were examined. X-ray diffraction analysis, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy were used to evaluate the crystalline phase and microstructure of the composites made using the powder metallurgy process. A micro-Vickers hardness tester was used to test the mechanical properties. During heat treatment, mixed products Al13Co4 and Al9Co2 were generated in the aluminium matrix through reactive diffusion in solid state. The results show, on the one hand, that the obtained alloys have microhardness values that are significantly higher than those of pure aluminum (49 ± 4 HV). In contrast, the microhardness of alloys based on the compositions ‘Al-0.5% Co’ and ‘Al-1%Co’ increases with the sintering time and achieves a maximum value of 153.89 ± 4.85 HV and 141.49 ± 7.81 HV, respectively, at a sintering time of 72h. Nevertheless, the microhardness decreases with longer sintering times of 72h for the higher compositions that were studied ‘Al-3%Co’ et ‘Al-5%Co’. After 48 h of sintering, the microhardness of the ‘Al-3% Co’ alloy falls from 131.88 ± 2.50 HV to 102.67 ± 4.33 HV. For the alloy ‘Al-5%Co’, it decreases from 93.87 ± 2.50 HV to 64.65 ±2.50 HV after 24 h of sintering. This decrease in hardness is explained by the generation of a large amount of pores during the sintering of the alloys with large compositions. The electrochemical behavior of these composites was studied in this work.
BAHAJ Imane is a PhD student at Hassan First University. He belongs to Morocco. He obtained his master degree in applied chemistry option: Physical-Chemistry of Materials in 2017 from Mohamed First University, at the Faculty of Sciences Oujda. At present, he joined the research laboratoty; Physical-Chemistry of Process and Materials; in 2018. He prepared his thesis under the theme of ‘Thermodynamic of the Elaboration of materials composites and evaluation of their mechanical,thermal and electrochemical properties’. Their interest is to have the materials stable thermodynamically with good mechanical resistance and higher durability. He is looking for in parallel a postdoc who is interested in the following fields: Batteries, Storage Energy, Hydrogen Storage, Materials Science,Thermodynamic, Electrochemistry.
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Evaluations of scientific productions are traditionally made by h-index which is defined by only the most cited publications neglecting significant part of scientists’ productions. Also, h-index can be rapidly increased by networking effects (friendship citations) leading to critical evaluation aspect of scientific productivity under reduced conception and frequent manipulation ways. This calls for bibliometric revisions through more integrative and more robust ways. In this framework, a new simplex simulation approach was developed for functional evaluations of scientific productions by highlighting regulation trends between structural variables of publications, and by considering whole sets of papers. Initially, publications are classified according to predefined criteria; then, their contents are structurally characterized by relative levels of production and cooperation variables including the numbers of pages, figures, tables, authors, affiliations, countries, etc. Using Scheffé’s mixture designs, simplex simulation iteratively combined structural variability of different publications’ classes by varying their relative weights. In response to combinations, a complete set of smoothed barycentric publication patterns was calculated. This response matrix represented system backbone from which regulation trends between production and cooperation variables were highlighted for different publications’ class. Application was illustrated by analyzing populations of Tunisian biological and medical researchers initially classified into 6 classes combining three h-index ranges with two citation levels of papers ( h or < h). Production variables showed positive trends leading to higher vs lower productivity ratios in scientists’ classes associated with lower and higher h-index ranges, respectively. Moreover, papers’ citations were improved by slight increase vs significant decrease of coauthors’ numbers, respectively. These functional results highlighted production ratios and trends that are inaccessible by h-index. By its integrative and flexible aspects, simplex simulation approach calls for developing international projects aiming for scientific productivity analyses at different scales (scientists, institutions, countries, etc.) by considering open classification criteria.
Nabil Semmar, PhD in phytochemistry (Lyon 2000), is full Professor in biological engineering at the University of Tunis El Manar (Tunisia). Since 2004, he teaches biostatistics and data mining to license, master, engineer and doctorate levels. He followed long multidisciplinary training (1988-2004) combining biological and chemical fields with computational tools (Algiers-Marseilles-Lyon Paris). In PhD, he developed a new simplex simulation method helping to highlight regulation processes governing polymorphic patterns in metabolic systems from chromatographic data. Since 2007, he published his simulation approach in many fields including plant metabolism, animal behaviors, environment assessment, pharmacology, food control, chemical synthesis and scientific production analysis. He was invited by several organisms including IAEA (Vienna, 2008) and Federal University of Parana (Brazil, 2017) to present his simulation approach. Since 2009, he edited 3 international books and 14 book chapters. In 2016, he cofounded the laboratory of bioInformatics, bioMathematics and bioStatistics in Pasteur Institute of Tunis.
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Very recently, pseudobrookite Fe2TiO5 has been surfaced as a promising photocatalyst for the oxidation half-reaction of overall water splitting. This semiconductor is inexpensive, non-toxic, possesses a relatively small band gap, and presents adequate structural and photochemical features. In this seminar, I will talk about the performance of Fe2TiO5 nanoparticles as a suspended water splitting photocatalyst, both in the pristine form and after specific modifications, such as doping and loading of cocatalysts onto the surface of the nanoparticles. The pristine nanoparticles were synthesized through a facile solvothermal method, also used for the doping processes, whereas sputtering deposition was employed for the cocatalyst loadings. All these approaches were efficient to prolong the charge carrier’s diffusion length, reduce charge recombination, and accelerate the kinetics of the redox reactions at the solid/liquid interface, under visible light illumination. The procedure generated single-phase pristine, Sn- and Nb doped Fe2TiO5 nanoparticles with dimensions close to 30 nm and optical band gap values of 2.1 eV. When aqueous suspensions of pristine Fe2TiO5, 1.0 at% Sn-doped Fe2TiO5 and 1.5 at% Nb-doped Fe2TiO5 were irradiated by simulated sunlight for 5h, evolutions of 59.2, 297.6 and 344.0 mol h-1 g-1 of O2 were observed, respectively. These results reflect the substantial improvement that doping Fe2TiO5 with Sn and Nb confers to its photocatalytic water splitting activity. On the other hand, the deposition of nanostructured NiO, Co3O4, NiFeOx and CoFeOx cocatalysts resulted in O2 productions of 204.0, 470.4, 504.0, and 448.0 mol h-1 g-1 within 5h. Electrochemical and photoelectrochemical measurements indicated that reductions in the charge carrier transfer resistance at the solid/ liquid interface plays an important role for the performance improvements of the modified nanomaterials. Overall, this work illustrates how structural alterations of a potential photocatalyst can improve photochemical energy conversion.
Mauricio A. Melo is currently an adjunct professor at the Fluminense Federal University (UFF) in Rio de Janeiro, Brazil. He graduated and received his MA and PhD degrees in Inorganic Chemistry from the University of Campinas (UNICAMP). From 2015 to 2018, he worked as a postdoctoral researcher at the University of California, Davis (UCD). He was also a postdoctoral fellow at the University of São Paulo (USP) in 2019. His range of knowledge encompasses materials chemistry and solar energy conversion into fuels with inorganic nanomaterials as photocatalysts.
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One of the enduring propositions of technology futures is the crafting of material artefacts with Internet connectivity, allowing for the embodiment of a congruent digital shadow. Such propositions have a long history, dating back to the 1990s, which saw the rise of the Internet and the ongoing miniaturisation of transistors for the rise of mobile phones. It was envisaged that these resources could be successfully combined to achieve the complexity and scale required for the Internet of Things (IoT). Also, this provides such propositions with the opportunity to evolve with our cultural aspirations, while reflecting on the current state of perceived technological development. So, we consider to what extent past technology futures of digital materiality for the IoT have been realised, including hybrid artefacts that are transcendent across the physical and the digital, between the material and the immaterial. While these 'technology futures' have been proffered through many media depictions, seemingly heading towards everyday environments, the vast majority never arrive. We therefore propose a model for understanding, from a speculative design approach, the pathways of how emerging technologies become realised in real-world applications and technology related imaginaries, as well as how they ‘could’ be realised in credible near- futures. We also suggest reasons why these future visions of the IoT in everyday environments so often fail to be realised, and how to present more plausible depictions. This includes understanding failed propositions focused on utilitarian artefacts, and better understanding material culture for the ubiquitous embodiment of digital materiality in plausible depictions. We conclude by considering what is required for credible, engaging and critical speculations on understanding digital materiality for the IoT, including potentially preferable futures of connecting all human made objects in the world to the Internet.
Gerard Briscoe is a Research Fellow at the Royal College of Art's Helen Hamlyn Centre for Design. His research concerns Technology Futures, focusing on interdisciplinary design- computing research in designing digital cultures for preferable futures. Distinct phenomena of these digital cultures have emerged, including the shrinking of physical distance and the dissolution of material reality. So, It involves exploring speculative design for equity in emerging technologies for all abilities, which requires understanding digital materiality, resistance to digitisation and cyborg post-humanism. His expertise in interdisciplinarity comes from nearly two decade’s experience with inter- and multi disciplinary research. Specifically, between computing research with first natural sciences, then social sciences, followed by business research, and most recently design research. He gained his B/MEng in Computing, and PhD in Electrical and Electronic Engineering, from Imperial College London.
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The current shortages in single use (SU) supply chains show how dependent both industry and academia are from only a few vendors worldwide. This is severely hindering fundamental research and process development for the COVID pandemic response and will do so in future. With 3D printing technology we can manufacture SU equipment on demand and on site. In this study we investigated different commercially available low-cost materials and their compatibility for cell culture. We identified poly lactic acid (PLA) as perfect candidate for 3D printed parts for cell culture applications. The worldwide supply chain issues for SU shaking flasks and bioreactors prompted us to develop 3D printed counterparts to maintain our HEK293 cell culture intended for bionanoparticle production. The shaking flasks were designed in Autodesk inventor 3D CAD. Materials tested represent the market of different 3D printing technologies and low-cost materials, ranging from UV-polymerizing resin printers to thermoplastic printers. The different materials were tested with HEK293 cells under standard conditions. Cell growth and viability were monitored daily. Our tests showed that only PLA has the same growth behavior as the commercially available SU flasks. We suspect that volatile organic compounds (VOC) inhibit cell growth for resin-based materials and have a toxic effect on the cell culture. We were able to show that heat treatment to reduce the VOC concentration was of partial success (data not shown). Moreover, we present the application for insect cells intended for virus like particle production and show the potential uses of customized equipment such as custom made bioreactors with geometries that are not possible to achieve with any other methodology than 3D printing. While 3D printed SU ware is very unlikely to be universally adopted as a full replacement for all SU-labware, it could be of interest to low income countries, given the sharp decrease in prices of 3D printers in recent years and low costs of PLA filament (~15 €/kg equivalent to ~33 $/lb).
Lena Achleitner is a PhD candidate at the austrian centre of industrial biotechnology in Vienna, Austria working on process development for novel vaccines. She discovered 3D printing for biotechnology during her Master thesis on continuous protein purification with hydrocyclones and enjoys exploring the potentials of 3D printing for cell culture applications together with her supervisor Peter Satzer.
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