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Topic Review
Functional Properties of LSM and LSCF Air Electrodes
An analysis of the literature data on the electrical, thermal, mechanical, and electrochemical properties of the conventional perovskite-type cathode materials shows that lanthanum strontium manganite (La,Sr)MnO3 (LSM) fulfils all the requirements for its use in high-temperature SOFCs. However, as the temperature decreases, the use of LSM materials, which are predominantly electronic conductors with a low level of ionic conductivity, becomes unsatisfactory due to their low electrochemical activity for the oxygen reduction reaction (ORR). On the other hand, cobalt-based perovskite materials, including lanthanum strontium cobaltite ferrite (La,Sr)(Co,Fe)O3−δ (LSCF), are characterized by superior catalytic activity due to high values of both electronic and ionic conductivity.
  • 2.7K
  • 24 Jul 2023
Topic Review
Human Embryonic Heart Start Beating
The onset of embryonic heart beating may be regarded as the defining feature for the beginning of personal human life. Clarifying the timing of the first human heartbeat, therefore, has religious, philosophical, ethical, and medicolegal implications.
  • 2.7K
  • 20 Jun 2022
Topic Review
Caracal
The caracal (Caracal caracal) /ˈkærəkæl/ is a medium-sized wild cat native to Africa, the Middle East, Central Asia, and arid areas of Pakistan and northwestern India . It is characterised by a robust build, long legs, a short face, long tufted ears, and long canine teeth. Its coat is uniformly reddish tan or sandy, while the ventral parts are lighter with small reddish markings. It reaches 40–50 cm (16–20 in) at the shoulder and weighs 8–19 kg (18–42 lb). It was first scientifically described by German naturalist Johann Christian Daniel von Schreber in 1776. Three subspecies are recognised. Typically nocturnal, the caracal is highly secretive and difficult to observe. It is territorial, and lives mainly alone or in pairs. The caracal is a carnivore that typically preys upon small mammals, birds, and rodents. It can leap higher than 4 metres (12 ft) and catch birds in midair. It stalks its prey until it is within 5 m (16 ft) of it, after which it runs it down and kills its prey with a bite to the throat or to the back of the neck. Both sexes become sexually mature by the time they are one year old and breed throughout the year. Gestation lasts between two and three months, resulting in a litter of one to six kittens. Juveniles leave their mothers at the age of nine to ten months, though a few females stay back with their mothers. The average lifespan of captive caracals is nearly 16 years. Caracals were tamed and used for coursing in India, Persia and Egypt.
  • 2.7K
  • 24 Oct 2022
Topic Review
Prognostic Biomarkers in Patients with Acute Myocardial Infarction
Despite all the important advances in its diagnosis and treatment, acute myocardial infarction (AMI) is still one of the most prominent causes of morbidity and mortality worldwide. Early identification of patients at high risk of poor outcomes through the measurement of various biomarker concentrations might contribute to more accurate risk stratification and help to guide more individualized therapeutic strategies, thus improving prognoses. 
  • 2.7K
  • 01 Sep 2022
Topic Review
Sol-Gel Technology
The commercial availability of inorganic/organic precursors for sol-gel formulations is very high and increases day by day. In textile applications, the precursor-synthesized sol-gels along with functional chemicals can be deposited onto textile fabrics in one step by rolling, padding, dip-coating, spraying or spin coating. By using this technology, it is possible to provide fabrics with functional/multi-functional characteristics including flame retardant, anti-mosquito, water- repellent, oil-repellent, anti-bacterial, anti-wrinkle, ultraviolet (UV) protection and self-cleaning properties. These surface properties are discussed, describing the history, basic chemistry, factors affecting the sol-gel synthesis, progress in sol-gel technology along with various parameters controlling sol-gel technology. Additionally, this review deals with the recent progress of sol-gel technology in textiles in addressing fabric finishing, water repellent textiles, oil/water separation, flame retardant, UV protection and self-cleaning, self-sterilizing, wrinkle resistance, heat storage, photochromic and thermochromic color changes and the improvement of the durability and wear resistance properties.
  • 2.7K
  • 05 May 2023
Topic Review
Basalt Fibre Reinforced Composites
Basalt mineral fibre, made directly from basalt rock, has good mechanical behavior, superior thermal stability, better chemical durability, good moisture resistance and can easily be recycled when compared to E-glass fibres (borosilicate glass is called ‘E-glass’ or ‘electric al-grade glass’ because of its high electrical resistance) which are traditionally used in structural composites for industrial applications. Industrial adoption of basalt fibre reinforced composites (FRC) is still very low mainly due to inadequate data and lower production volumes leading to higher cost. These reasons constrain the composites industry from seriously considering basalt as a potential alternative to conventional (e.g., E-glass) fibre reinforced composites for different applications.
  • 2.7K
  • 17 Jan 2023
Topic Review
Metal Nanoclusters
Metal nanoclusters (NCs), comprising only a few to roughly hundreds of metal atoms, have a metal core-protective agent shell structure. Owing to the size of metal NCs approaching the Fermi wavelength of electrons, the spatial confinement of free electrons in metal NCs generates discrete electronic transitions, thereby exhibiting intriguing molecular-like properties. Therefore, metal NCs are deemed to bridge the gap between molecules and nanoparticles.
  • 2.7K
  • 01 Dec 2020
Topic Review
Serious Gaming for Behaviour Change
Serious games (SG) are defined as “interactive computer applications, with or without a significant hardware component, that have challenging goals, are fun to play and engaging, incorporate some scoring mechanism, and supply the user with skills, knowledge or attitudes useful in reality".
  • 2.7K
  • 28 Mar 2022
Topic Review
Cryptographically-Secure Pseudorandom Number Generator
A cryptographically secure pseudorandom number generator (CSPRNG) or cryptographic pseudorandom number generator (CPRNG) is a pseudorandom number generator (PRNG) with properties that make it suitable for use in cryptography. It is also loosely known as a cryptographic random number generator (CRNG) (see Random number generation § "True" vs. pseudo-random numbers). Most cryptographic applications require random numbers, for example: key generation nonces salts in certain signature schemes, including ECDSA, RSASSA-PSS The "quality" of the randomness required for these applications varies. For example, creating a nonce in some protocols needs only uniqueness. On the other hand, the generation of a master key requires a higher quality, such as more entropy. And in the case of one-time pads, the information-theoretic guarantee of perfect secrecy only holds if the key material comes from a true random source with high entropy, and thus any kind of pseudorandom number generator is insufficient. Ideally, the generation of random numbers in CSPRNGs uses entropy obtained from a high-quality source, generally the operating system's randomness API. However, unexpected correlations have been found in several such ostensibly independent processes. From an information-theoretic point of view, the amount of randomness, the entropy that can be generated, is equal to the entropy provided by the system. But sometimes, in practical situations, more random numbers are needed than there is entropy available. Also, the processes to extract randomness from a running system are slow in actual practice. In such instances, a CSPRNG can sometimes be used. A CSPRNG can "stretch" the available entropy over more bits.
  • 2.7K
  • 20 Oct 2022
Topic Review
Pakistan Institute of Nuclear Science & Technology
Located in Nilore, it maintains a broad portfolio in providing post-graduate and post-doctoral research opportunities in supercomputing, renewable energy, physical, philosophical, materials, environmental, and mathematical sciences. Researchers and scholars are invited from universities throughout Pakistan.
  • 2.7K
  • 10 Nov 2022
Topic Review
Gamified Physical Exercise and Mental Health in Adolescence
Interest in gamified physical activity has been driven by its potential to benefit student mental health. Integrating gamified practices for mental health improvement represents a significant innovation within multidisciplinary approaches to enhancing mental well-being. Gamified physical activity positively influences adolescents’ mental health and well-being. Additionally, there is a need for improved application and game design to enhance learning within school contexts. Tailoring exergames to fit specific disciplines and school-related characteristics can promote healthier mobile application usage and offer significant benefits for the mental health of young individuals.
  • 2.7K
  • 23 Jan 2024
Biography
John Ellis
Jonathan Richard Ellis CBE FRS HonFInstP (born 1 July 1946[1]) is a British theoretical physicist who is currently Clerk Maxwell Professor of Theoretical Physics at King's College London.[2] After completing his secondary education at Highgate School, he attended King's College, Cambridge, earning his PhD in theoretical (high-energy) particle physics in 1971. After brief post-doc positions in t
  • 2.7K
  • 17 Nov 2022
Topic Review
Timeline of Plague
This is a timeline of plague, describing major epidemics and key medical developments.
  • 2.7K
  • 14 Nov 2022
Topic Review
Energy Use in Hotels
Hotel chains are reported as one of the most energy-intensive sectors and a growing number of international studies on this theme have been developed. An understanding of energy consumption is crucial for the tourism sector because the high energy cost directly affects accommodation prices and the final profitability of companies.
  • 2.7K
  • 25 Jul 2022
Topic Review
Depression of 1920–21
The Depression of 1920–21 was a sharp deflationary recession in the United States and other countries, beginning 14 months after the end of World War I. It lasted from January 1920 to July 1921. The extent of the deflation was not only large, but large relative to the accompanying decline in real product. There was a two-year post–World War I recession immediately following the end of the war, complicating the absorption of millions of veterans into the economy. The economy started to grow, but it had not yet completed all the adjustments in shifting from a wartime to a peacetime economy. Factors identified as contributing to the downturn include returning troops, which created a surge in the civilian labor force and problems in absorbing the veterans; a decline in labor union strife; changes in fiscal and monetary policy; and changes in price expectations. Following the end of the depression, the Roaring Twenties brought a period of economic prosperity.
  • 2.7K
  • 18 Oct 2022
Topic Review
Energy Efficiency, Vibrations and Noise of Fan
Fans as industrial devices are among the most significant single recipients of driving energy. Therefore, they represent an important area of energy savings to reduce CO2 emissions. The ubiquity of fans and their operation under conditions different from the optimum provides an opportunity for more significant global reductions in the energy used to drive them. The second important aspect, besides energy efficiency, related to the operation of fans is the noise they generate.
  • 2.7K
  • 08 Feb 2023
Topic Review
High-Mix, Low-Volume Manufacturing Industry
The high-mix, low-volume (HMLV) industry has seen growth in the need for product customisation with research to increase manufacturers’ flexibility for the variation in market demands. Industries with HMLV insights are discussed, to reveal production sectors and research areas, categorising the research work, type of validation and their applications.
  • 2.7K
  • 29 May 2023
Topic Review
Starch-Based Materials
Starch is one of the most common biodegradable polymers found in nature, and it is widely utilized in the food and beverage, bioplastic industry, paper industry, textile, and biofuel industries. Starch has received significant attention due to its environmental benignity, easy fabrication, relative abundance, non-toxicity, and biodegradability. 
  • 2.7K
  • 25 Nov 2021
Topic Review
Nanojoining
Nanojoining is the process of joining two or more surfaces together using nanomaterials as the primary building blocks. This includes, but is not limited to, nanosoldering, nanobrazing, nanowelding, nanoscale diffusion bonding, and additive manufacturing. Note that, like with conventional soldering and brazing, only the filler metal undergoes melting, not the base material. Nanomaterials are materials in which at least one dimension 100 nm or less and include 0-D (e.g. nanoparticles, 1-D (e.g. nanowires and nanorods), 2-D (e.g. graphene), and 3-D (e.g. nanofoam) materials. Nanomaterials exhibit several notable properties that allow joining to occur at temperatures lower than the melting temperature of their bulk counterpart. For example, the melting temperature of Ag is 961.78 °C, but Ag nanomaterials begin to melt at a much lower temperature that is dependent depending on the size and shape. These properties include high surface area to volume ratio, the Gibbs-Thompson effect, and high surface energy. The low joining temperature of nanomaterials has been exploited numerous times for flexible electronics, printable electronics, and soldering applications; only within the last two decades have they been explored for high-temperature joining applications (>450 °C).
  • 2.7K
  • 07 Jul 2022
Topic Review
Benign Migratory Glossitis
Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.
  • 2.7K
  • 27 Sep 2022
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