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Topic Review
Asymmetric Conductivity in Heavy-Fermion Metals
We consider the time reversal T and particle-antiparticle C symmetries that, being most fundamental, can be violated at microscopic level by a weak interaction. The notable example here is from condensed matter, where strongly correlated Fermi systems like HF metals and high-Tc superconductors (or HF compounds) exhibit C and T symmetries violation due to the so-called non-Fermi liquid (NFL) behavior rather than to microscopic inter-particle interaction. When a HF compound is near the topological fermion condensation quantum phase transition (FCQPT), it exhibits the NFL properties, so that the C symmetry breaks down, making the differential tunneling conductivity to be an asymmetric function of the bias voltage V. This asymmetry does not take place in normal metals, where Landau Fermi liquid (LFL) theory holds. Under the application of magnetic field, a HF compound transits to the LFL state, and σ(V) becomes symmetric function of V. These findings are in good agreement with experimental observations. We suggest that the same topological FCQPT defines the baryon asymmetry in the Universe. Thus, the most fundamental features of the nature are defined by its topological and symmetry properties.
  • 2.9K
  • 29 Apr 2021
Topic Review
Chasing the Elusive Luciferin
In dinoflagellates, the mechanisms related to the bioluminescent phenomenon have been well studied; however, at present, some points that remain unknown still persist. That is the case of luciferin biosynthesis, which has been reported to be an intricate process with several metabolic pathways involved. In the context of this controversial scenario, various hypotheses about the biosynthesis of luciferin in dinoflagellates are presented.
  • 2.9K
  • 05 Jan 2026
Topic Review
Illegal Toxic Waste Dumping
Poor management of hazardous waste can lead to environmental pollution, injuries, and adverse health risks. Children’s exposure to hazardous waste may cause serious acute and chronic health problems due to their higher vulnerability to the toxic effects of chemicals. 
  • 2.9K
  • 24 Mar 2021
Topic Review
Regulation of Unmanned Aerial Vehicles
The use of unmanned aerial vehicles (UAVs) is generally regulated by the national aviation authority of the country.
  • 2.9K
  • 31 Oct 2022
Topic Review
Foundational Principles and Adaptation of the Achilles Tendon
Achilles tendinopathy (AT) is defined as consistent pain in the Achilles tendon coupled with a loss of function associated with mechanical loading. Achilles tendinopathy can either be classified as insertional AT (symptoms localized 0–2 cm from the distal insertion; 20–25% of Achilles tendon injuries) or midportion AT (symptoms localized 2–7 cm proximal to the insertion; 55–65% of Achilles tendon injuries).
  • 2.9K
  • 01 Sep 2022
Topic Review
Underwater Sensing Technologies and Applications
Currently, a variety of sensing methods based on optics, acoustics, and electromagnetics are widely applied for ocean observation and exploration. Acoustic sensing contains various sonar devices for seafloor mapping, submersible navigation, and underwater object. Optical sensing technologies applied to ocean exploration include underwater imaging for objects inspection, spectrophotometry, and fluorophotometry for environmental parameters monitoring. Technologies of electromagnetics are used for underwater metal detection such as mines and mineral resources, and for underwater inspections of cables and pipelines.
  • 2.9K
  • 13 Dec 2021
Topic Review
Thermoresponsive Hydrogel Molecule
Temperature-induced, rapid changes in the viscosity and reproducible 3-D structure formation makes thermos-sensitive hydrogels an ideal delivery system to act as a cell scaffold or a drug reservoir. Moreover, the hydrogels’ minimum invasiveness, high biocompatibility, and facile elimination from the body have gathered a lot of attention from researchers.
  • 2.9K
  • 08 Aug 2022
Topic Review
The Feynman Lectures on Physics
The Feynman Lectures on Physics is a physics textbook based on some lectures by Richard P. Feynman, a Nobel laureate who has sometimes been called "The Great Explainer". The lectures were presented before undergraduate students at the California Institute of Technology (Caltech), during 1961–1963. The book's co-authors are Feynman, Robert B. Leighton, and Matthew Sands. The Feynman Lectures on Physics is perhaps the most popular physics book ever written. More than 1.5 million English-language copies have been sold; probably even more copies have been sold in a dozen foreign-language editions. A 2013 review in Nature described the book as having "simplicity, beauty, unity ... presented with enthusiasm and insight".
  • 2.9K
  • 27 Oct 2022
Topic Review Peer Reviewed
Effects of in Utero SARS-CoV-2 Exposure on Newborn Health Outcomes
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 600 million people worldwide, including millions of pregnant women. While newborns exposed to other viruses in utero are sometimes at high risk for vertical transmission, a substantial body of literature since early 2020 has demonstrated that vertical transmission of SARS-CoV-2 from infected mother to neonate is rare, and that newborns who do become infected with SARS-CoV-2 generally have favorable outcomes. In this review, the authors evaluate the existing literature on vertical transmission of SARS-CoV-2 and its potential mechanisms and discuss short- and long-term health outcomes in newborns who were exposed to SARS-CoV-2 in utero. The authors conclude that vertical transmission and adverse neonatal and infant/child outcomes are unlikely, but that neonates exposed to prenatal maternal SARS-CoV-2 infection may be at slightly higher risk for preterm birth, possibly related to increased risk of severe COVID-19 disease in pregnant women, placental changes, or infection timing. Ultimately, the need for additional and longer-term follow-up data in this population is highlighted.
  • 2.9K
  • 12 Jan 2023
Topic Review
Innovative Tools in Farm Animals’ Early Disease Diagnosis
As the importance of farming continues to grow, innovative technology and sensors play an increasingly important role. Automation and robots in agriculture have the potential to play a significant role in helping society fulfill its future demands for food supply. Wearable sensors connected to or within cows can monitor eating, rumination, pH, body temperature, laying behavior, animal activity, animal position or placement, and more.
  • 2.9K
  • 16 Mar 2023
Topic Review
Human Cytomegalovirus
Human cytomegalovirus (HCMV) expresses a variety of viral regulatory proteins that undergo close interaction with host factors including viral-cellular multiprotein complexes. The HCMV protein kinase pUL97 represents a viral CDK ortholog (vCDK) that determines the efficiency of HCMV replication via phosphorylation of viral and cellular substrates. A hierarchy of functional importance of individual pUL97-mediated phosphorylation events has been discussed, however, the most pronounced pUL97-dependent phenotype could be assigned to viral nuclear egress, as illustrated by genetic ORF-UL97 deletion or pharmacological pUL97 inhibition. Despite earlier data pointing to a cyclin-independent functionality, experimental evidence increasingly emphasized the role of pUL97-cyclin complexes. Consequently, the knowledge about pUL97 involvement in host interaction, viral nuclear egress and additional replicative steps led to the postulation of pUL97 as an antiviral target. Indeed, validation experiments in vitro and in vivo confirmed the sustainability of this approach. Consequently, current investigations of pUL97 in antiviral treatment go beyond the known pUL97-mediated ganciclovir prodrug activation and henceforward include pUL97-specific kinase inhibitors. Among a number of interesting small molecules analyzed on experimental and preclinical stages, maribavir is presently investigated in clinical studies and, in the near future, might represent a first kinase inhibitor applied in the field of antiviral therapy.
  • 2.9K
  • 29 Oct 2020
Topic Review
Smart Tourism Ecosystem
For the sustainable tourism experience, a smart tourism ecosystem is created so that personalized, context awareness, as well as real-time monitoring, can be ensured.
  • 2.9K
  • 01 Dec 2022
Topic Review
Seagate Barracuda
The Seagate Barracuda is a series of hard disk drives and later solid state drives produced by Seagate Technology that was first introduced in 1993. The line initially focused on high-capacity, high-performance SCSI hard drives until introducing ATA models in 1999 and SATA models in 2002. Since 2001, the Barracuda is Seagate's most popular product line as the hard disk drive industry started to move to a 7200 RPM spindle speed.
  • 2.9K
  • 30 Sep 2022
Topic Review
Low-Voltage GaN FETs in Motor Control Application
The efficiency and power density improvement of power switching converters play a crucial role in energy conversion. In the field of motor control, this requires an increase in the converter switching frequency together with a reduction in the switching legs’ dead time. This target turns out to be complex when using pure silicon switch technologies. Gallium Nitride (GaN) devices have appeared in the switching device arena in recent years and feature much more favorable static and dynamic characteristics compared to pure silicon devices. In the field of motion control, there is a growing use of GaN devices, especially in low voltage applications.
  • 2.9K
  • 29 Oct 2021
Topic Review
Alloying Elements and Mechanical Characteristics of Mg-Based Materials
Magnesium alloys are widely employed in various applications due to their high strength-to-weight ratio and superior mechanical properties as compared to unalloyed Magnesium. Alloying is considered an important way to enhance the strength of the metal matrix composite but it significantly influences the damping property of pure magnesium, while controlling the rate of corrosion for Mg-based material remains critical in the biological environment. Therefore, it is essential to reinforce the magnesium alloy with a suitable alloying element that improves the mechanical characteristics and resistance to corrosion of Mg-based material. Biocompatibility, biodegradability, lower stress shielding effect, bio-activeness, and non-toxicity are the important parameters for biomedical applications other than mechanical and corrosion properties. The development of various surface modifications is also considered a suitable approach to control the degradation rate of Mg-based materials, making lightweight Mg-based materials highly suitable for biomedical implants. 
  • 2.9K
  • 01 Sep 2022
Topic Review
Actor
An actor or actress is a person who portrays a character in a performance. The actor performs "in the flesh" in the traditional medium of the theatre or in modern media such as film, radio, and television. The analogous Greek term is ὑποκριτής (Script error: No such module "Ancient Greek".), literally "one who answers". The actor's interpretation of a role—the art of acting—pertains to the role played, whether based on a real person or fictional character. This can also be considered an "actor's role," which was called this due to scrolls being used in the theaters. Interpretation occurs even when the actor is "playing themselves", as in some forms of experimental performance art. Formerly, in Ancient Greece and the medieval world, and in England at the time of William Shakespeare, only men could become actors, and women's roles were generally played by men or boys. While Ancient Rome did allow female stage performers, only a small minority of them were given speaking parts. The commedia dell’arte of Italy, however, allowed professional women to perform early on; Lucrezia Di Siena, whose name is on a contract of actors from 10 October 1564, has been referred to as the first Italian actress known by name, with Vincenza Armani and Barbara Flaminia as the first primadonnas and the first well-documented actresses in Italy (and in Europe). After the English Restoration of 1660, women began to appear onstage in England. In modern times, particularly in pantomime and some operas, women occasionally play the roles of boys or young men.
  • 2.9K
  • 02 Oct 2022
Topic Review
LPCS for Metal-Ceramic/Ceramic Coatings
Based on the recent analysis of various databases, cold spray (CS), the newest method among thermal spraying technologies, has received the unabated attention of hundreds of researchers continuously since its invention in the 1980s. The significance of CS lies in the low process temperature, which usually ensures compressive residual stresses and allows for the formation of coatings on a thermally sensitive substrate. 
  • 2.9K
  • 13 Sep 2021
Topic Review
Phytoestrogen
Phytoestrogens are compounds derived from plants that have a similar structure to human sex hormones. 
  • 2.9K
  • 26 Jan 2021
Topic Review
Sustainable Wireless Sensor Network Based Environmental Monitoring
Wireless sensor networks (WSN) are the base of the Internet of Things (IoT) that all together give rise to the smart city. These WSNs consist of several sensors, which are densely distributed to observe physical or environmental conditions, like humidity, temperature, light intensity, and gas concertation. The sensors reading data are transmitted to the network coordinator, the IP-gateway, which is at the heart of the wireless network.
  • 2.9K
  • 27 Jul 2022
Topic Review
Mineralogy of Antimony Ores and Antimony Production
Antimony is a metalloid element having common oxidation states of 5+ and 3+. It is a lustrous silvery-white solid, which is quite brittle and exhibits a flaky texture.  Antimony is classified as a critical/strategic metal. Stibnite, jamesonite, and antimony-gold ores are the most common sources of antimony.
  • 2.9K
  • 02 Sep 2022
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