The manipulation of magnetic properties by an electric field in magnetoelectric multiferroic materials has driven significant research activity, with the goal of realizing their transformative ...technological potential. Here, we review progress in the fundamental understanding and design of new multiferroic materials, advances in characterization and modelling tools to describe them, and the exploration of devices and applications. Focusing on the translation of the many scientific breakthroughs into technological innovations, we identify the key open questions in the field where targeted research activities could have maximum impact in transitioning scientific discoveries into real applications.
Occurrence of microplastics (plastic debris <5 mm) along the coast is a growing concern worldwide, due to increased input of discarded wastes from various sources. In order to evaluate the extent of ...microplastic pollution on the sandy beaches (25 locations) along Tamil Nadu coast (1076 km), India, microplastic debris were quantified and categorized into four different size classes. The beaches were classified according to potential sources of pollution i.e. riverine, tourism and fisheries. Beach samples collected from the high tide line contained significantly higher abundance of microplastic than at the low tide line. Beaches adjacent to rivers exhibited relatively higher microplastic abundance compared to those influenced by tourism and fishing activities. Out of the total detected debris, plastic fragments were the maximum (47–50%), followed by line/fibres (24–27%) and foam (10–19%) materials. Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed that polyethylene, polypropylene, and polystyrene were the main types of microplastics present in these beaches. Gut content analysis of commercially important fishes, collected from the coastal waters, revealed microplastics ingestion in 10.1% of fishes. The results indicate that microplastics accumulation in the coastal environment, especially close to the river mouths, may be a serious concern, due to its ability to enter into the marine food web and highlights the necessity of microplastics screening from estuarine, coastal waters and other potential sources.
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•Microplastic particles were studied at 25 beaches along the southeast coast of India.•Highest abundance of microplastics was recorded on beaches adjacent to river mouth.•Polyethylene and polypropylene were the most abundant microplastics in the beaches.•Microplastics were found in 10.1% of the 79 fishes representing 5 species.•Fragments were the dominant microplastic available both in beaches and fish gut.
Multiferroic materials, which show simultaneous ferroelectric and magnetic ordering, exhibit unusual physical properties - and in turn promise new device applications - as a result of the coupling ...between their dual order parameters. We review recent progress in the growth, characterization and understanding of thin-film multiferroics. The availability of high-quality thin-film multiferroics makes it easier to tailor their properties through epitaxial strain, atomic-level engineering of chemistry and interfacial coupling, and is a prerequisite for their incorporation into practical devices. We discuss novel device paradigms based on magnetoelectric coupling, and outline the key scientific challenges in the field.
We review recent developments and advances in multiferroic and magnetoelectric heterostructures. Driven by the promise of new materials functionality (i.e. electric field control of ferromagnetism), ...extensive on-going research is focused on the search for and characterization of new multiferroic materials. In this review we develop a comprehensive overview of multiferroic materials, including details on the nature of order parameters and coupling in these materials, the scarcity of such materials in single phase form, routes to create and control the properties of these materials, and we finish by investigating such effects in a number of model materials and heterostructures. This includes an in-depth discussion of BiFeO3, an investigation of recent advances in magnetoelectric materials, and an introduction to a variety of approaches by which one can achieve novel materials functionality.
Macrophages are one of the principal immune effector cells that play essential roles as secretory, phagocytic, and antigen-presenting cells in the immune system. In this study, we address the issue ...of cytotoxicity and immunogenic effects of gold nanoparticles on RAW264.7 macrophage cells. The cytotoxicity of gold nanoparticles has been correlated with a detailed study of their endocytotic uptake using various microscopy tools such as atomic force microscopy (AFM), confocal-laser-scanning microscopy (CFLSM), and transmission electron microscopy (TEM). Our findings suggest that Au(0) nanoparticles are not cytotoxic, reduce the production of reactive oxygen and nitrite species, and do not elicit secretion of proinflammatory cytokines TNF-α and IL1-β, making them suitable candidates for nanomedicine. AFM measurements suggest that gold nanoparticles are internalized inside the cell via a mechanism involving pinocytosis, while CFLSM and TEM studies indicate their internalization in lysosomal bodies arranged in perinuclear fashion. Our studies thus underline the noncytotoxic, nonimmunogenic, and biocompatible properties of gold nanoparticles with the potential for application in nanoimmunology, nanomedicine, and nanobiotechnology.
This article is written on behalf of many colleagues, collaborators, and researchers in the field of complex oxides as well as current and former students and postdocs who continue to enable and ...undertake cutting-edge research in the field of multiferroics, magnetoelectrics, and the pursuit of electric-field control of magnetism. What I present is something that is extremely exciting from both a fundamental science and applications perspective and has the potential to revolutionize our world, particularly from a sustainability perspective. To realize this potential will require numerous new innovations, both in the fundamental science arena as well as translating these scientific discoveries into real applications. Thus, this article will attempt to bridge the gap between fundamental materials physics and the actual manifestations of the physical concepts into real-life applications. I hope this article will help spur more translational research within the broad materials community.
•Gene mutation of SARS-CoV-2 has been rapidly emerging and transmitting all over the world during the COVID-19 pandemic.•Constructed and probed a stochastically perturbed dominant variant of the ...coronavirus epidemic model with three nonlinear saturated incidence rates.•The existence of a unique ergodic stationary distribution implies stochastic weak stability.•Our dominant variant stochastic model provides an important impact and effect, with an increase in enormous coronavirus infections and moralities among susceptible, exposed, hyper spreaders, infectious but asymptomatic, hospitalized and recovered individuals.•Public health bureaucrats are urging to probe more on mutated and variant of COVID-19 virus and to prepare potential booster vaccines for protecting the people against numerous variants of coronavirus.
During the COVID-19 pandemic, the SARS-CoV-2 gene mutation has been rapidly emerging and spreading all over the world. Experts worldwide regularly monitor genetic mutations and variants through genome-sequence-based surveillance, laboratory testing, outbreak investigation, and epidemiological probing. Clinical pathologists and medical laboratory scientists prefer developing or endorsing COVID-19 vaccines with a broader immune response involving various antibodies and cells to protect against mutations or new variants. Randomness plays an enormous role in pathology and epidemiology. Hence, based on epidemiological parameter data, we construct and probe a stochastically perturbed dominant variant of the coronavirus epidemic model with three nonlinear saturated incidence rates. We reveal the existence of a unique global positive solution to the constructed stochastic COVID-19 model. The Lyapunov function method is used to determine the presence of a stationary distribution of positive solutions. We derive sufficient conditions for the coronavirus to be eradicated. Eventually, numerical simulations validate the effectiveness of our theoretical outcomes.
Since the re-emergence of multi-ferroics and magnetoelectrics almost a decade ago, bismuth ferrite has been among the most heavily studied model system. It is a multi-ferroic with robust ...ferroelectricity and antiferromagnetism, in conjunction with weak ferromagnetism arising primarily from spin-orbit coupling effects. This material system has generated a significant amount of discussion in the community, because many of the physical properties measured in thin films are different from the bulk. This paper summarizes some of the key observations in this versatile materials system, with a particular focus on thin films, heterostructures and interfacial phenomena.
Abstract
We report spectral and polarimeter observations of two weak, low-frequency (≈85–60 MHz) solar coronal type II radio bursts that occurred on 2020 May 29 within a time interval ≈2 minutes. The ...bursts had fine structures, and were due to harmonic plasma emission. Our analysis indicates that the magnetohydrodynamic shocks responsible for the first and second type II bursts were generated by the leading edge (LE) of an extreme-ultraviolet flux rope/coronal mass ejection (CME) and interaction of its flank with a neighboring coronal structure, respectively. The CME deflected from the radial direction by ≈25° during propagation in the near-Sun corona. The estimated power spectral density and magnetic field strength (
B
) near the location of the first burst at heliocentric distance
r
≈ 1.35
R
⊙
are ≈2 × 10
−3
W
2
m and ≈1.8 G, respectively. The corresponding values for the second burst at the same
r
are ≈10
−3
W
2
m and ≈0.9 G. The significant spatial scales of the coronal turbulence at the location of the two type II bursts are ≈62–1 Mm. Our conclusions from the present work are that the turbulence and magnetic field strength in the coronal region near the CME LE are higher compared to the corresponding values close to its flank. The derived estimates of the two parameters correspond to the same
r
for both the CME LE and its flank, with a delay of ≈2 minutes for the latter.
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