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Topic Review
Starship (Spacecraft)
Starship is the fully reusable second stage and space vehicle of the SpaceX BFR "Super Heavy" rocket currently under development by SpaceX. It is a long-duration cargo- and passenger-carrying spacecraft that also serves as the BFR launch vehicle second stage and integrated payload section. Three 9-meter (30 ft)-diameter stainless steel Starship test articles are being built, and one had already begun integrated system testing by March 2019. The Starship test flight rocket—Starhopper—will be used for initial integrated testing of the Raptor rocket engine with a flight-capable propellant structure as well as for low-altitude, low-velocity flight testing of launches and landings. It began hotfire testing in April 2019. Two additional test articles, Starship orbital prototypes, are being built by competing teams in South Texas and along the space coast of Florida. They are planned to be used after mid-2019 for high-altitude, high-velocity testing. Integrated system testing of Starhopper, including the first flight test, began in April 2019. SpaceX is planning to launch commercial payloads using Starship no earlier than 2021.
  • 6.8K
  • 21 Oct 2022
Topic Review
Glass–Ceramics
Owing to their combinations of unique properties of sintered ceramics and the distinctive characteristics of glasses, glass-ceramics have attracted great interest from both academia and industry worldwide since their accidental discovery in 1953.
  • 6.8K
  • 27 Oct 2020
Topic Review
Small and Medium Enterprises (SMEs) Performance
SMEs are one of the business entities that make a significant contribution to economic conditions in Indonesia. This is the reason why information about the condition and presence of SMEs is important data for the government as an indicator for Indonesia’s economic conditions, especially during the COVID-19 pandemic. 
  • 6.8K
  • 23 May 2022
Topic Review
Reverse Water Gas Shift Reaction
The catalytic conversion of CO2 to CO by the reverse water gas shift (RWGS) reaction followed by well-established synthesis gas conversion technologies could be a practical technique to convert CO2 to valuable chemicals and fuels in industrial settings. For catalyst developers, prevention of side reactions like methanation, low-temperature activity, and selectivity enhancements for the RWGS reaction are crucial concerns. Cerium oxide (ceria, CeO2) has received considerable attention due to its exceptional physical and chemical properties. 
  • 6.8K
  • 09 Oct 2022
Topic Review
Artificial Intelligence in Archaeology
Artificial Intelligence (AI), due to its increasingly powerful predictive capabilities, is showing an increasing trend in attracting widespread interest in many sciences. Archaeologists now can more fully exploit the knowledge from an extensive amount of archaeological data with the use of artificial intelligence in such a way as to make decisions related to appropriate strategies for the preservation and protection of archaeological elements, as well as to decide on the most ideal point excavation in a complex cultural landscape. 
  • 6.8K
  • 30 Nov 2022
Topic Review
Eurostar
Eurostar is an international high-speed rail service connecting the United Kingdom with France , Belgium and the Netherlands. Most Eurostar trains travel through the Channel Tunnel between the United Kingdom and France, owned and operated separately by Getlink. The London terminus is London St Pancras International; the other British calling points are Ebbsfleet International and Ashford International in Kent. Intermediate calling points in France are Calais-Fréthun and Lille-Europe. Trains to Paris terminate at Gare du Nord. Trains to Belgium and the Netherlands serve Brussels-South and Rotterdam Centraal, before terminating at Amsterdam Centraal. Additionally, in France there are direct services from London to Marne-la-Vallée–Chessy (Disneyland Paris) and seasonal direct services to southern France (Lyon, Avignon and Marseille) in summer, and to the French Alps in winter. The service is operated by 11 Class 373/1 trainsets, each with 18 coaches, and 17 Class 374 trainsets, each with 16 coaches. The trains run at up to 320 kilometers per hour (200 mph) on high-speed lines. The LGV Nord high-speed line in France opened before Eurostar services began in 1994, and newer lines enabling faster journeys were added later: HSL 1 in Belgium and High Speed 1 in south-east England. The French and Belgian parts of the network are shared with Paris–Brussels Thalys services and TGV trains. Eurostar is operated by Eurostar International Limited (EIL), jointly owned by SNCF, the national railway of France (55%), investment firms (40%), and the National Railway Company of Belgium (5%).
  • 6.8K
  • 20 Nov 2022
Topic Review
Vectors in Gene Therapy for Pulmonary Diseases
Over the past decades, a better understanding of the genetic and molecular alterations underlying several respiratory diseases has encouraged the development of new therapeutic strategies. Gene therapy offers new therapeutic alternatives for inherited and acquired diseases by delivering exogenous genetic materials into cells or tissues to restore physiological protein expression and/or activity.
  • 6.8K
  • 16 Mar 2022
Topic Review
Non-Ionic Surfactants
Surfactants are essential in the manufacture of polymeric nanoparticles by emulsion formation methods and to preserve the stability of carriers in liquid media. The deposition of non-ionic surfactants at the interface allows a considerable reduction of the globule of the emulsion with high biocompatibility and the possibility of oscillating the final sizes in a wide nanometric range.
  • 6.8K
  • 29 Jun 2021
Topic Review
Lipid-Based Nanoparticles
COVID-19 vaccines have been developed with unprecedented speed which would not have been possible without decades of fundamental research on delivery nanotechnology. Lipid-based nanoparticles have played a pivotal role in the successes of COVID-19 vaccines and many other nanomedicines, such as Doxil® and Onpattro®, and have therefore been considered as the frontrunner in nanoscale drug delivery systems. In this review, we aim to highlight the progress in the development of these lipid nanoparticles for various applications, ranging from cancer nanomedicines to COVID-19 vaccines. The lipid-based nanoparticles discussed in this review are liposomes, niosomes, transfersomes, solid lipid nanoparticles, and nanostructured lipid carriers. We particularly focus on the innovations that have obtained regulatory approval or that are in clinical trials. We also discuss the physicochemical properties required for specific applications, highlight the differences in requirements for the delivery of different cargos, and introduce current challenges that need further development. This review serves as a useful guideline for designing new lipid nanoparticles for both preventative and therapeutic vaccines including immunotherapies.
  • 6.8K
  • 19 May 2021
Topic Review
Fundamentals of Chlorine Disinfection
Chlorine first reacts with organic and inorganic matters before pathogens inactivation. The amount of chlorine consumed in this process is termed chlorine demand. The combined chlorine that forms together with any free available chlorine in the water is called the chlorine residual. This is the component of the added chlorine that disinfects the water. Free available chlorine is formed by differences in the concentrations of hypochlorous and hypochlorite ions, a process that depends on the pH of the water. Even though the chlorination procedure is well-researched, establishing an appropriate chlorine dose remains a difficult task for many field applications. Nevertheless, the effective chlorine dose should be sufficient to destroy pathogens and oxidize the organic contaminants as well as maintain sufficient free available chlorine in the water distribution system, post-chlorination.
  • 6.8K
  • 06 Jun 2022
Topic Review
Muesli
Muesli (/ˈmjuːzli/ MEWZ-lee; Template:Lang-gsw Template:IPA-gsw, non-Swiss Standard German: Müsli [ˈmyːsli] (listen)) is a cold oatmeal dish based on rolled oats and ingredients like grains, nuts, seeds and fresh or dried fruits. This mix may be combined with one or more liquids like milk, almond milk, other plant milks, yogurt, or fruit juice and left for a time to soften the oats before being consumed. Developed around 1900 by Swiss physician Maximilian Bircher-Benner for patients in his hospital, it is now eaten as a standard breakfast dish, and also in Switzerland as a supper called Birchermüesli complet: muesli with Café complet (milk coffee, accompanied with bread, butter, and jam. (Butterbrot)).
  • 6.8K
  • 15 Nov 2022
Topic Review
Carbon fiber-reinforced Thermoplastic polymers
Carbon fiber-reinforced thermoplastic polymers are considered a promising composite for many industrial applications including in the automation, renewable energy, and aerospace industries. They exhibit exceptional properties such as a high strength-to-weight ratio and high wear resistance and stiffness, which give them an advantage over other conventional materials such as metals.
  • 6.8K
  • 17 Aug 2021
Topic Review
First Generation of Intellectual Movements in Iran
First Generation of Intellectual movements in Iran (Persian: نسل اول جنبش های روشنفکری در ایران‎, romanized: Nasl-e Aval-e Jonbesh Hay-e Roshan Fekri dar Iran) or Iranian Enlightenment (Persian: روشنگری ایرانی‎, romanized: Roshangari-e Irani) was a period in the mid-19th- to early-20th- century in Iran, which was accompanied by new ideas in the traditional Iranian society. During the rule of the Qajar dynasty, and especially after the defeat of Iran, in the war with the Russian Empire, due to cultural exchanges, new ideas were formed among the educated class of Iran. This military defeat also encouraged the Qajar commanders to overcome the backwardness. The establishment of Dar ul-Fonun, the first modern university in Iran and the arrival of foreign professors, caused the thoughts of European thinkers to enter Iran, followed by the first signs of enlightenment and intellectual movements in Iran. During this period, intellectual groups were formed in Secret societies and secret associations. Among these Secret societies, we can mention Mirza Malkam Khan's "Faramosh Khaneh" (based on Masonic lodges), Anjoman-e Bagh-e Meykadeh, Society of Humanity and Mokhadarat Vatan Association. These groups spread their ideas by distributing leaflets and newspapers. These secret societies stressed the need to reform the land and administrative system and reduce the role of the clergy in society, as well as to limit the rulers within the framework of the law. Iranian thinkers based their work on confronting religious traditions, they were confronted with Shia Islam, which on the one hand was mixed with superstitions, and on the other hand, the strictness and intellectual prejudice of some religious people caused intellectual-scientific decline. Among the thinkers of this period were Mirza Malkam Khan, Mirza Abdul'Rahim Talibov, Mirza Fatali Akhundov, Iraj Mirza, Mirzadeh Eshghi, Aref Qazvini, Mirza Hassan Roshdieh, Mirza Aqa Khan Kermani, Hassan Taqizadeh, Amir Kabir and Haydar Khan Amo-oghli. Most of these intellectuals expressed their thoughts through poetry and fiction, simple stories and parables that were easier for people to understand helped to spread Enlightenment throughout Iran. The first generation of intellectuals in Iran went beyond the borders of this country and influenced neighboring countries such as Afghanistan and the Arab world such as Egypt. People like Jamāl al-Dīn al-Afghānī collaborated with most of the great thinkers of this period from Iran.
  • 6.8K
  • 05 Dec 2022
Topic Review
Social Construction of Disability
The social construction of disability comes from a paradigm of ideas that suggest that society's beliefs about a particular community, group or population are grounded in the power structures inherent in a society at any given time. These are often steeped in historical representations of the issue and social expectations surrounding concepts such as disability, thereby enabling a social construct around what society deems disabled and healthy. Ideas surrounding disability stem from societal attitudes, often connected to who is deserving or undeserving, and deemed productive to society at any given time. For example, in the medieval period, a person's moral behavior established disability. Disability was a divine punishment or side effect of a moral failing; being physically or biologically different was not enough to be considered disabled. Only during the European Enlightenment did society change its definition of disability to be more related to biology. However, what most Western Europeans considered to be healthy determined the new biological definition of health.
  • 6.8K
  • 11 Nov 2022
Topic Review
Fedora (Operating System)
Fedora is a Linux distribution developed by the community-supported Fedora Project which is sponsored primarily by Red Hat, a subsidiary of IBM, with additional support from other companies. Fedora contains software distributed under various free and open-source licenses and aims to be on the leading edge of free technologies. Fedora is the upstream source of the commercial Red Hat Enterprise Linux distribution and for CentOS. Fedora is a fork of Red Hat Linux since RHL was discontinued in 2003. Since the release of Fedora 30, five different editions are currently available: Workstation, focused on the personal computer, Server for servers, CoreOS, focused on cloud computing, Silverblue, focused on an immutable desktop specialized to container-based workflows and IoT, focused on IoT devices. (As of February 2016), Fedora has an estimated 1.2 million users, including Linus Torvalds ((As of May 2020)), creator of the Linux kernel.
  • 6.8K
  • 27 Oct 2022
Topic Review
Allosaurus
Allosaurus (/ˌæləˈsɔːrəs/) is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch (Kimmeridgian to late Tithonian). The name "Allosaurus" means "different lizard" alluding to its unique (at the time of its discovery) concave vertebrae. It is derived from the Greek ἄλλος (allos) ("different, other") and σαῦρος (sauros) ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Allosaurus was a large bipedal predator. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. It averaged 8.5 meters (28 ft) in length for A. fragilis, with the largest specimens estimated as being 9.7 metres (32 ft) long. Relative to the large and powerful hindlimbs, its three-fingered forelimbs were small, and the body was balanced by a long and heavily muscled tail. It is classified as an allosaurid, a type of carnosaurian theropod dinosaur. The genus has a complicated taxonomy, and includes at least three valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains have come from North America's Morrison Formation, with material also known from Portugal. It was known for over half of the 20th century as Antrodemus, but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry brought the name "Allosaurus" back to prominence and established it as one of the best-known dinosaurs. As the most abundant large predator in the Morrison Formation, Allosaurus was at the top of the food chain, probably preying on contemporaneous large herbivorous dinosaurs, and perhaps other predators. Potential prey included ornithopods, stegosaurids, and sauropods. Some paleontologists interpret Allosaurus as having had cooperative social behavior, and hunting in packs, while others believe individuals may have been aggressive toward each other, and that congregations of this genus are the result of lone individuals feeding on the same carcasses.
  • 6.8K
  • 16 Nov 2022
Topic Review
Modern Stoicism
Modern Stoicism is an intellectual and popular movement that began at the end of the 20th century aimed at reviving the practice of Stoicism. It is not to be confused with neostoicism, an analogous phenomenon in the 17th century. The term "modern Stoicism" covers both the revival of interest in the Stoic philosophy and the philosophical efforts to adjust ancient Stoicism to the language and conceptual framework of the present. The rise of modern Stoicism has received attention in the international media since around November 2012 when the first Annual Stoic Week event was organized.
  • 6.8K
  • 04 Nov 2022
Topic Review
Aero L-159 Alca
The Aero L-159 ALCA[nb 1] is a subsonic light combat aircraft and advanced trainer developed in the single-seat L-159A and two-seat L-159B versions respectively, produced in the Czech Republic by Aero Vodochody. In 2003, the Czech Air Force fleet of 72 L-159A aircraft was reduced to 24 due to budget constraints. After several years of storage, the government has re-sold most of the redundant aircraft to both military and civilian operators, namely the Iraqi Air Force and Draken International. The L-159 has seen active combat use by the Iraqi Air Force against ISIS. In Draken's service, the L-159 (colloquially known as "Honey Badger") has been employed as an aggressor aircraft. Since 2007, six L-159A aircraft have been rebuilt into T1 trainer derivatives. In 2017, Aero Vodochody unveiled a newly built L-159T1 for the Iraqi Air Force while the Czech Air Force is set to acquire L-159T2 two-seaters.
  • 6.7K
  • 29 Nov 2022
Topic Review
Hindu Views on Monotheism
Hinduism incorporates diverse views on the concept of God. Different traditions of Hinduism have different theistic views, and these views have been described by scholars as polytheism, monotheism, henotheism, panentheism, pantheism, monism, agnostic, humanism, atheism or Nontheism. Monotheism is the belief in a single creator God and the lack of belief in any other Creator. Hinduism is not a monolithic faith and different sects may or may not posit or require such a belief. Religion is considered a personal belief in Hinduism and followers are free to choose the different interpretations within the framework of Karma and reincarnation. Many forms of Hinduism believe in a monotheistic God, such as Krishna followers, Vedanta, Arya samaj, Samkhya school of Vedas etc, Many traditions within Hinduism share the Vedic idea of a metaphysical ultimate reality and truth called Brahman instead. According to Jan Gonda, Brahman denoted the "power immanent in the sound, words, verses and formulas of Vedas" in the earliest Vedic texts. The early Vedic religious understanding of Brahman underwent a series of abstractions in the Hindu scriptures that followed the Vedic scriptures. These scriptures would reveal a vast body of insights into the nature of Brahman as originally revealed in the Vedas. These Hindu traditions that emerged from or identified with the Vedic scriptures and that maintained the notion of a metaphysical ultimate reality would identify that ultimate reality as Brahman. Hindu adherents to these traditions within Hinduism revere Hindu deities and, indeed, all of existence, as aspects of the Brahman. The deities in Hinduism are not considered to be almighty, omnipotent, omniscient and omnibenevolent, and spirituality is considered to be seeking the ultimate truth that is possible by a number of paths. Like other Indian religions, in Hinduism, deities are born, they live and they die in every kalpa (eon, cycle of existence). In Hindu philosophy, there are many different schools. Its non-theist traditions such as Samkhya, early Nyaya, Mimamsa and many within Vedanta such as Advaita do not posit the existence of an almighty, omnipotent, omniscient, omnibenevolent God (monotheistic God), while its theistic traditions posit a personal God left to the choice of the Hindu. The major schools of Hindu philosophy explain morality and the nature of existence through the karma and samsara doctrines, as in other Indian religions. Contemporary Hinduism can be categorized into four major traditions: Vaishnavism, Shaivism, Shaktism, and Smartism. Vaishnavism, Shaivism, and Shaktism worship Vishnu, Shiva, and Devi — the Divine Mother — as the Supreme respectively, or consider all Hindu deities as aspects of the formless Supreme Reality or Brahman. Other minor sects such as Ganapatya and Saura focus on Ganesha and Surya as the Supreme. A sub-tradition within the Vaishnavism school of Hinduism that is an exception is dualistic Dvaita, founded by Madhvacharya in the 13th-century (where Vishnu as Krishna is a monotheistic God). This tradition posits a concept of monotheistic God so similar to Christianity that Christian missionaries in colonial India suggested that Madhvacharya was likely influenced by early Christians who migrated to India, a theory that has been discredited by scholars. Furthermore, many adherents consider these similarities to be superficial and insubstantial; for example, Madhvacharya postulates three co-eternal fundamental realities, consisting of Supreme Being (Vishnu or paramathma), individual souls (jīvātman), and inanimate matter.
  • 6.7K
  • 15 Nov 2022
Topic Review
Pet Husbandry
Pet husbandry is the practices applied in day-to-day care of animal companions, which can greatly impact animal welfare. Pet husbandry include: (1) origin of pets; (2) number and type of pets in the household; (3) diet type and feeding practices; (4) living environment and daily activities; (5) preventive treatment for parasites and vaccination; (6) regular veterinary check-ups and access to health care; and (7) compliance with legal requirements and identification.
  • 6.7K
  • 29 Oct 2020
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