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Topic Review
Lagrangian Point
In celestial mechanics, the Lagrangian points (/ləˈɡrɑːndʒiən/ also Lagrange points, L-points, or libration points) are the points near two large bodies in orbit where a smaller object will maintain its position relative to the large orbiting bodies. At other locations, a small object would go into its own orbit around one of the large bodies, but at the Lagrangian points the gravitational forces of the two large bodies, the centripetal force of orbital motion, and (for certain points) the Coriolis acceleration all match up in a way that cause the small object to maintain a stable or nearly stable position relative to the large bodies. There are five such points, labeled L1 to L5, all in the orbital plane of the two large bodies, for each given combination of two orbital bodies. For instance, there are five Lagrangian points L1 to L5 for the Sun–Earth system, and in a similar way there are five different Lagrangian points for the Earth–Moon system. L1, L2, and L3 are on the line through the centers of the two large bodies, while L4 and L5 each act as the third vertex of an equilateral triangle formed with the centers of the two large bodies. L4 and L5 are stable, which implies that objects can orbit around them in a rotating coordinate system tied to the two large bodies. Several planets have trojan satellites near their L4 and L5 points with respect to the Sun. Jupiter has more than a million of these trojans. Artificial satellites have been placed at L1 and L2 with respect to the Sun and Earth, and with respect to the Earth and the Moon. The Lagrangian points have been proposed for uses in space exploration.
  • 5.9K
  • 17 Nov 2022
Topic Review
LD-Steelmaking
Basic Oxygen Furnace (BOF) steelmaking is, worldwide, the most frequently applied process. According to the world steel organization statistical report, 2021, it saw a total production share of 73.2%, or 1371.2 million tons per year of the world steel production in 2020. The rest is produced in Electric Arc Furnace (EAF)-based steel mills (26.3%), and only a very few open-hearth and induction furnace-based steel mills. The BOF technology remains the leading technology applied based on its undoubted advantages in productivity and liquid steel composition control. The BOF technology started as the LD process 70 years ago, with the first heat applied in November 1952 in a steel mill in Linz, Austria. The name LD was formed from the first letters of the two sites with the first industrial scale plants, Linz and Donawitz, both in Austria. The history and development of the process have been honored in multiple anniversary publications over the last few decades. Nevertheless, the focus of the steel industry worldwide is significantly changing following a social and political trend and the requirement for fossil-free energy generation and industrial production to be in accordance with the world climate targets committed to in relation to the decades leading up to 2050.
  • 5.9K
  • 09 Jun 2022
Topic Review
Two-Dimensional Silicon Carbide
Two-dimensional silicon carbide (2D SiC) is a single/few atomic layer of silicon carbide.   2D SiC has a graphene-like honeycomb structure consisting of alternating Si and C atoms. In the monolayer SiC, the C and Si atoms bond through  sp2 hybridization to form the SiC sheet.  As a direct wide bandgap semiconducting material, 2D SiC has the potential to bring revolutionary advances into power electronics, optoelectronic and other SiC-based devices. It can overcome current limitations with silicon, bulk SiC, and gapless graphene. In addition to SiC, which is the most stable form of monolayer silicon carbide, other compositions, i.e. SixCy, are also predicted to be energetically favorable. Depending on the stoichiometry and bonding, monolayer SixCy may behave as a semiconductor, semimetal or topological insulator. With different Si/C ratios, the emerging 2D silicon carbide materials could attain novel electronic, optical, magnetic, mechanical, and chemical properties that go beyond those of graphene, silicene, and already discovered 2D semiconducting materials.
  • 5.9K
  • 08 May 2022
Topic Review
Carcharodontosaurus
Carcharodontosaurus (/ˌkɑːrkəroʊˌdɒntoʊˈsɔːrəs/; lit. sharp-toothed lizard) is a genus of large carcharodontosaurid theropod dinosaur that existed during the Cenomanian age of the Late Cretaceous in Northern Africa. The genus Carcharodontosaurus is named after the shark genus Carcharodon, itself composed of the Greek karchar[os] (κάρχαρος, meaning "jagged" or "sharp") and odōn (ὀδών, "teeth"), and the suffix -saurus ("lizard"). It is currently known to have two species: C. saharicus and C. iguidensis.
  • 5.9K
  • 09 Nov 2022
Topic Review
Annular Erythemas and Purpuras
Annular dermatoses (AD) are a heterogeneous group of skin diseases, whose common feature is essentially the annular or circular arrangement of the lesions with centrifugal spreading. They belong to the group of figurate dermatoses, to which can be added linear or serpiginous dermatoses, for example. They are a fascinating curiosity for the dermatologist, as they form patterns and arabesques on the patient’s body.
  • 5.9K
  • 01 Jun 2023
Topic Review
Thyroid Function and Suicidal Behavior
Thyroid disease is a very common condition that influences the entire human body, including cognitive function and mental health. As a result, thyroid disease has been associated with multiple neuropsychiatric conditions. However, the relationship between thyroid dysfunction and suicide is still controversial. 
  • 5.9K
  • 28 Jul 2021
Topic Review
DRDO Rustom
The DRDO Rustom (English: Warrior) is a Medium Altitude Long Endurance unmanned air vehicle (UAV) being developed by Defence Research and Development Organisation for the three services, Indian Army, Indian Navy and the Indian Air Force of the Indian Armed Forces. Rustom is derived from the NAL's LCRA (Light Canard Research Aircraft) developed by a team under the leadership of late Prof Rustom Damania in the 1980s. The UAV will have structural changes and a new engine. Rustom will replace/supplement the Heron UAVs in service with the Indian armed forces.
  • 5.9K
  • 02 Nov 2022
Topic Review Peer Reviewed
Entropy
The concept of entropy constitutes, together with energy, a cornerstone of contemporary physics and related areas. It was originally introduced by Clausius in 1865 along abstract lines focusing on thermodynamical irreversibility of macroscopic physical processes. In the next decade, Boltzmann made the genius connection—further developed by Gibbs—of the entropy with the microscopic world, which led to the formulation of a new and impressively successful physical theory, thereafter named statistical mechanics. The extension to quantum mechanical systems was formalized by von Neumann in 1927, and the connections with the theory of communications and, more widely, with the theory of information were respectively introduced by Shannon in 1948 and Jaynes in 1957. Since then, over fifty new entropic functionals emerged in the scientific and technological literature. The most popular among them are the additive Renyi one introduced in 1961, and the nonadditive one introduced in 1988 as a basis for the generalization of the Boltzmann–Gibbs and related equilibrium and nonequilibrium theories, focusing on natural, artificial and social complex systems. Along such lines, theoretical, experimental, observational and computational efforts, and their connections to nonlinear dynamical systems and the theory of probabilities, are currently under progress. Illustrative applications, in physics and elsewhere, of these recent developments are briefly described in the present synopsis.
  • 5.9K
  • 07 May 2022
Topic Review
Disse (Space of Disse)
Space of Disse: a thin perisinusoidal area between the endothelial cells and hepatocytes filled with blood plasma, nutrients and oxygen, but also debris from our organism, that have acquired great importance in liver disease
  • 5.9K
  • 20 Feb 2021
Topic Review
Unintended Consequences
In the social sciences, unintended consequences (sometimes unanticipated consequences or unforeseen consequences) are outcomes of a purposeful action that are not intended or foreseen. The term was popularised in the twentieth century by American sociologist Robert K. Merton and expanded by economist Thomas Sowell and psychologist Stuart Vyse. Unintended consequences can be grouped into three types: Unexpected benefit: A positive unexpected benefit (also referred to as luck, serendipity or a windfall). Unexpected drawback: An unexpected detriment occurring in addition to the desired effect of the policy (e.g., while irrigation schemes provide people with water for agriculture, they can increase waterborne diseases that have devastating health effects, such as schistosomiasis). Perverse result: A perverse effect contrary to what was originally intended (when an intended solution makes a problem worse).
  • 5.9K
  • 14 Oct 2022
Topic Review Peer Reviewed
Structural Systems for Tall Buildings
Structural systems for tall buildings have gone through an evolutionary process. The rigid frame became popular in the first half of the 20th century but proved to be structurally inefficient beyond a certain height of tall buildings. The invention of the tubular structure in the 1960s allowed buildings to be built taller with low material consumption. Due to the obstructive nature of the closely spaced exterior columns of framed tubes and bracings of braced tubes, the core-outrigger system gained acceptance by the architects as it allowed them to freely articulate the façade design. However, the conventional tubular structures continued to retain their use for tall buildings to a lesser degree and later underwent a resurgence in modified forms. These and other advanced tubular forms in cutting-edge structural systems developed later continue to find application in modern times. This study presents a detailed narrative of different structural systems for tall buildings that is expected to assist structural engineers and architects to collaboratively select appropriate structural systems for tall buildings. 
  • 5.9K
  • 08 Jul 2022
Topic Review
Saltation
In biology, saltation (from la saltus 'leap, jump') is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps. Speciation, such as by polyploidy in plants, can sometimes be achieved in a single and in evolutionary terms sudden step. Evidence exists for various forms of saltation in a variety of organisms.
  • 5.9K
  • 29 Sep 2022
Topic Review
Bongo Drum
Bongos (Spanish: bongó) are an Afro-Cuban percussion instrument consisting of a pair of small open bottomed hand drums of different sizes. They are struck with both hands, most commonly in an eight-stroke pattern called martillo (hammer). They are mainly employed in the rhythm section of son cubano and salsa ensembles, often alongside other drums such as the larger congas and the stick-struck timbales. Bongo drummers (bongoseros) emerged as the only drummers of son cubano ensembles in eastern Cuba toward the end of the 19th century. The instrument remained important as son groups evolved into larger conjuntos and orchestras in Havana in the 1940s, at which point they began to share the stage with congas. Bongos later reached the United States, where they are commonly played in salsa, Afro-Cuban jazz, Latin rock and other genres. Bongo drums are about 20 centimetres (8 in) high and have diameters of approximately 20 centimetres (8 in) and 25 centimetres (10 in) (the smaller drum is called macho, male, and the larger drum, hembra, female). They are the smallest drums in Latin percussion, some models being only 15 centimetres (6 in) in diameter. The shells of the drums and the bridge (the small block that joins them) are usually made of wood, although fiberglass is also common. The heads are typically made of calfskin and attached to the shells via steel hardware that enables their tuning. Originally, metal tacks were used, so tuning had to be done by heating the skins.
  • 5.9K
  • 02 Nov 2022
Topic Review
Marine Battery Energy Storage Systems on Ships
The shipping industry is going through a period of technology transition that aims to increase the use of carbon-neutral fuels. There is a significant trend of vessels being ordered with alternative fuel propulsion. Shipping’s future fuel market will be more diverse, reliant on multiple energy sources. One of very promising means to meet the decarbonisation requirements is to operate ships with sustainable electrical energy by integrating local renewables, shore connection systems and battery energy storage systems (BESS). 
  • 5.9K
  • 20 Mar 2023
Topic Review
Mortal Kombat
Mortal Kombat is an American media franchise centered on a series of video games, originally developed by Midway Games in 1992. The development of the first game was originally based on an idea that Ed Boon and John Tobias had of making a video game starring Jean-Claude Van Damme, but as that idea fell through, a fantasy-themed fighting game was created instead, nonetheless paying homage to him with nut-cracking movie star character Johnny Cage, whose initials and personal style echo Van Damme's. Mortal Kombat was the first ever fighting game to introduce a secret fighter, reached if the player fulfilled a set of requirements. The original game has spawned many sequels and spin-offs consisting of several action-adventure games, as well as a comic book series and a card game. Film producer Lawrence Kasanoff licensed the rights to the game in the early 1990s and produced the first hit movie ever made from a video game. Lawrence also produced the second movie, animated TV series, live-action TV series films, the first one million platinum-selling album and a live-action tour. Mortal Kombat has become the most successful fighting franchise in the history of video games and one of the highest-grossing media franchises of all time. The series has a reputation for high levels of graphic violence, including, most notably, its Fatalities (finishing moves allowing the player to finish off their defeated opponent). Controversies surrounding Mortal Kombat, in part, led to the creation of the ESRB video game rating system. Early games in this series were also noted for their realistic digitized sprites and an extensive use of palette swapping to create new characters. Following Midway's bankruptcy, the Mortal Kombat development team was acquired by Warner Bros. Entertainment and turned into NetherRealm Studios.
  • 5.9K
  • 19 Oct 2022
Topic Review
Egyptian Medical Papyri
Egyptian medical papyri are ancient Egyptian texts written on papyrus which permit a glimpse at medical procedures and practices in ancient Egypt. The papyri give details on disease, diagnosis, and remedies of disease, which include herbal remedies, surgery, and magical spells. It is thought there were more medical papyri, but many have been lost due to grave robbing. The largest study of the medical papyri to date has been undertaken by Humboldt University of Berlin and was titled Medizin der alten Ägypter ("Medicine of ancient Egypt"). Early Egyptian medicine was based mostly on a mixture of magic and religious spells. Most commonly "cured" by use of amulets or magical spells, the illnesses were thought to be caused by spiteful behavior or actions. Afterwards, doctors performed various medical treatments if necessary. The instructions for these medical rituals were later inscribed on papyrus scrolls by the priests performing the actions.
  • 5.8K
  • 07 Nov 2022
Topic Review
Public Parks
Public parks are a part of the public spaces of a city. Cities are rediscovering the potential of urban parks to advance environmental sustainability and enhance its social amenities.
  • 5.8K
  • 16 Jan 2022
Topic Review
Mechanisms of Essential oils on Central Nervous System
Essential oils (EOs) are naturally occurring complex mixtures of volatile odor compounds synthesized as secondary metabolites by plants and are extracted through steam distillation, solvent extraction, maceration, cold press extraction, water distillation, and CO2 extraction. Novel methods that are more efficient and provide higher yields include supercritical fluid extraction, microwave-assisted extraction, and ultrasound. Studies conducted on animals and humans have shown that EOs can produce a variety of central nervous system (CNS) targeted pharmacological effects such as anxiolytic effect, neuroprotection, antidepressant effect, anticonvulsant effect, analgesic, and sedative effect, to name a few. As a result, EOs can be used as an adjuvant therapy to prevent and relieve symptoms associated with CNS-based disorders such as insomnia, depression, dementia, Alzheimer’s disease (AD), etc.
  • 5.8K
  • 10 Feb 2022
Topic Review
Post-Translational Modification
Post-translational modifications (PTMs) add a layer of complexity to the proteome through the addition of biochemical moieties to specific residues of proteins, altering their structure, function and/or localization. Mass spectrometry (MS)-based techniques are at the forefront of PTM analysis due to their ability to detect large numbers of modified proteins with a high level of sensitivity and specificity.
  • 5.8K
  • 29 Apr 2021
Topic Review
Effector-Triggered Immunity in Plants
Plants rely on multiple immune systems to protect themselves from pathogens. When pattern-triggered immunity (PTI)—the first layer of the immune response—is no longer effective as a result of pathogenic effectors, effector-triggered immunity (ETI) often provides resistance. In ETI, host plants directly or indirectly perceive pathogen effectors via resistance proteins and launch a more robust and rapid defense response. Resistance proteins are typically found in the form of nucleotide-binding and leucine-rich-repeat-containing receptors (NLRs). Upon effector recognition, an NLR undergoes structural change and associates with other NLRs. The dimerization or oligomerization of NLRs signals to downstream components, activates “helper” NLRs, and culminates in the ETI response. Originally, PTI was thought to contribute little to ETI. However, most recent studies revealed crosstalk and cooperation between ETI and PTI.
  • 5.8K
  • 31 May 2021
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