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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%).
  • 6.5K
  • 20 Nov 2022
Topic Review
Sulfate-Reducing Microorganisms
Sulfate-reducing microorganisms (SRM) or sulfate-reducing prokaryotes (SRP) are a group composed of sulfate-reducing bacteria (SRB) and sulfate-reducing archaea (SRA), both of which can perform anaerobic respiration utilizing sulfate (SO42–) as terminal electron acceptor, reducing it to hydrogen sulfide (H2S). Therefore, these sulfidogenic microorganisms "breathe" sulfate rather than molecular oxygen (O2), which is the terminal electron acceptor reduced to water (H2O) in aerobic respiration. Most sulfate-reducing microorganisms can also reduce some other oxidized inorganic sulfur compounds, such as sulfite (SO32–), dithionite (S2O42–), thiosulfate (S2O32–), trithionate (S3O62–), tetrathionate (S4O62−), elemental sulfur (S8), and polysulfides (Sn2−). Depending on the context, "sulfate-reducing microorganisms" can be used in a broader sense (including all species that can reduce any of these sulfur compounds) or in a narrower sense (including only species that reduce sulfate, and excluding strict thiosulfate and sulfur reducers, for example). Sulfate-reducing microorganisms can be traced back to 3.5 billion years ago and are considered to be among the oldest forms of microbes, having contributed to the sulfur cycle soon after life emerged on Earth. Many organisms reduce small amounts of sulfates in order to synthesize sulfur-containing cell components; this is known as assimilatory sulfate reduction. By contrast, the sulfate-reducing microorganisms considered here reduce sulfate in large amounts to obtain energy and expel the resulting sulfide as waste; this is known as dissimilatory sulfate reduction. They use sulfate as the terminal electron acceptor of their electron transport chain. Most of them are anaerobes; however, there are examples of sulfate-reducing microorganisms that are tolerant of oxygen, and some of them can even perform aerobic respiration. No growth is observed when oxygen is used as the electron acceptor. In addition, there are sulfate-reducing microorganisms that can also reduce other electron acceptors, such as fumarate, nitrate (NO3−), nitrite (NO2−), ferric iron [Fe(III)], and dimethyl sulfoxide. In terms of electron donor, this group contains both organotrophs and lithotrophs. The organotrophs oxidize organic compounds, such as carbohydrates, organic acids (e.g., formate, lactate, acetate, propionate, and butyrate), alcohols (methanol and ethanol), aliphatic hydrocarbons (including methane), and aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene). The lithotrophs oxidize molecular hydrogen (H2), for which they compete with methanogens and acetogens in anaerobic conditions. Some sulfate-reducing microorganisms can directly utilize metallic iron [Fe(0)] as electron donor, oxidizing it to ferrous iron [Fe(II)].
  • 6.5K
  • 04 Nov 2022
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.
  • 6.5K
  • 05 Dec 2022
Topic Review
Major Applications of Smart Agriculture
With the rise of new technologies, such as the Internet of Things, raising the productivity of agricultural and farming activities is critical to improving yields and cost-effectiveness. IoT, in particular, can improve the efficiency of agriculture and farming processes by eliminating human intervention through automation. The fast rise of Internet of Things (IoT)-based tools has changed nearly all life sectors, including business, agriculture, surveillance, etc. These radical developments are upending traditional agricultural practices and presenting new options in the face of various obstacles.
  • 6.5K
  • 24 Jan 2022
Topic Review
Gaia Hypothesis
The Gaia hypothesis (/ˈɡaɪ.ə/), also known as the Gaia theory, Gaia paradigm, or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet. The hypothesis was formulated by the chemist James Lovelock and co-developed by the microbiologist Lynn Margulis in the 1970s. Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. The suggestion that the theory should be called "the Gaia hypothesis" came from Lovelock's neighbour, William Golding. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis. Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth. The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.
  • 6.5K
  • 07 Nov 2022
Topic Review
Current Applications of Membrane Bioreactors
A membrane bioreactor (MBR) can be described as a chamber designed for a biochemical transformation combined with a membrane separation process. The membrane can be used for different purposes inside the bioreactor, such as the addition of a reactant or the selective removal of one of the reaction products. Moreover, membranes can be utilized to retain the biocatalyst or act as the support for the biocatalyst or for the separation of enzymes by size exclusion.
  • 6.5K
  • 21 Oct 2020
Topic Review
Hydrothermal Liquefaction of Biomass
Hydrothermal liquefaction is a high-temperature high-pressure thermochemical conversion method adapted to convert high-water content biomass feedstocks to biofuels and many other valuable industrial chemicals. The hydrothermal process is broadly classified into carbonization, liquefaction, and gasification with hydrothermal liquefaction conducted in the intermediate temperature range of 250–374 °C and pressure of 4–25 MPa. Over the years, various solvents and co-solvents have been used as conversion mediums to promote easy decomposition of the lignocellulosic components in biomass. To obtain the final products, the product separation process typically involves multiple extraction and evaporation steps, which greatly depend on the type of extractive solvents and process parameters. In general, the main aim of the hydrothermal process is to produce a primary product, such as bio-oil, biochar, gases, or industrial chemicals, such as adhesives, benzene, toluene, and xylene.
  • 6.4K
  • 19 Aug 2021
Topic Review Peer Reviewed
Social, Cultural, and Economic Determinants of Well-Being
Individual well-being is influenced by a number of economic and social factors that include income, mental health, physical health, education, social relationships, employment, discrimination, government policies, and neighborhood conditions. Well-being involves both physical and mental health as part of a holistic approach to health promotion and disease prevention. The well-being of a society’s people has the potential to impact the well-being and productivity of the society as a whole. Though it may be assessed at the individual level, well-being becomes an important population outcome at the macro level and therefore represents a public health issue. 
  • 6.4K
  • 27 Jun 2022
Topic Review
Teachers’ Role during the COVID-19 Pandemic
A teacher’s professional role embodies a multitude of implications. Generally, its meaning has improved through professional experience over time. The concept of a teacher’s professional role is dynamic and is formed and reformed through time. The teacher’s professional role is indispensable to education. Without the professional role of teachers, school activities are difficult to be carried out effectively.
  • 6.4K
  • 17 Feb 2022
Topic Review
Congregation for the Doctrine of the Faith
The Congregation for the Doctrine of the Faith (Latin: Congregatio pro Doctrina Fidei; CDF) is the oldest among the nine congregations of the Roman Curia. It was founded to defend the church from heresy; today, it is the body responsible for promulgating and defending Catholic doctrine. Formerly known as the Supreme Sacred Congregation of the Roman and Universal Inquisition, it is informally known in many Catholic countries as the Holy Office, and between 1908 and 1965 was officially known as the Supreme Sacred Congregation of the Holy Office. Founded by Pope Paul III in 1542, the congregation's sole objective is to "spread sound Catholic doctrine and defend those points of Christian tradition which seem in danger because of new and unacceptable doctrines." Its headquarters are at the Palace of the Holy Office, just outside Vatican City. The congregation employs an advisory board including cardinals, bishops, priests, lay theologians, and canon lawyers. The current Prefect is Archbishop Luis Ladaria Ferrer, who was appointed by Pope Francis for a five-year term beginning July 2017.
  • 6.4K
  • 29 Sep 2022
Topic Review
Man-Eating Plant
A man-eating plant is a legendary carnivorous plant large enough to kill and consume a human or other large animal. Various such myths and fictional tales exist around the world.
  • 6.4K
  • 17 Nov 2022
Topic Review
Artificial Island
An artificial island or man-made island is an island that has been constructed by people rather than formed by natural means. Artificial islands may vary in size from small islets reclaimed solely to support a single pillar of a building or structure, to those that support entire communities and cities. Early artificial islands included floating structures in still waters, or wooden or megalithic structures erected in shallow waters (e.g. crannógs and Nan Madol discussed below). In modern times artificial islands are usually formed by land reclamation, but some are formed by the incidental isolation of an existing piece of land during canal construction (e.g. Donauinsel, Ko Kret, and much of Door County), or flooding of valleys resulting in the tops of former knolls getting isolated by water (e.g. Barro Colorado Island). One of the world's largest artificial islands, René-Levasseur Island, was formed by the flooding of two adjacent reservoirs.
  • 6.4K
  • 11 Oct 2022
Topic Review
Revolutions of 1848
The Revolutions of 1848, known in some countries as the Springtime of the Peoples or the Springtime of Nations, were a series of political upheavals throughout Europe in 1848. It remains the most widespread revolutionary wave in European history. The revolutions were essentially democratic and liberal in nature, with the aim of removing the old monarchical structures and creating independent nation-states. The revolutions spread across Europe after an initial revolution began in France in February. Over 50 countries were affected, but with no significant coordination or cooperation among their respective revolutionaries. Some of the major contributing factors were widespread dissatisfaction with political leadership, demands for more participation in government and democracy, demands for freedom of the press, other demands made by the working class, the upsurge of nationalism, the regrouping of established government forces, and the European Potato Failure, which triggered mass starvation, migration, and civil unrest. The uprisings were led by temporary coalitions of reformers, the middle classes ("the bourgeoisie") and workers. However, the coalitions did not hold together for long. Many of the revolutions were quickly suppressed; tens of thousands of people were killed, and many more were forced into exile. Significant lasting reforms included the abolition of serfdom in Austria and Hungary, the end of absolute monarchy in Denmark, and the introduction of representative democracy in the Netherlands. The revolutions were most important in France, the Netherlands, Italy, the Austrian Empire, and the states of the German Confederation that would make up the German Empire in the late 19th and early 20th century.
  • 6.4K
  • 05 Dec 2022
Topic Review
Wave Energy Converter
The overview of the types of wave energy converters (WECs) are classified through operational principle, absorbing wave direction, location, and power take-off.
  • 6.4K
  • 20 Oct 2020
Topic Review
Social Inertia
Social inertia refers to the tendency of social systems to resist change and maintain their existing state of equilibrium. It encompasses the collective reluctance or resistance within a society to adopt new ideas, practices, or norms, even in the face of external pressures or opportunities for change. Social inertia can arise from various factors, including cultural traditions, institutional structures, and psychological biases, and it often presents challenges for efforts to enact social reform or innovation.
  • 6.4K
  • 08 Feb 2024
Topic Review
Rehabilitation Robots
Rehabilitation is the process of treating post-stroke consequences. Impaired limbs are considered the common outcomes of stroke, which require a professional therapist to rehabilitate the impaired limbs and restore fully or partially its function. Due to the shortage in the number of therapists and other considerations, researchers have been working on developing robots that have the ability to perform the rehabilitation process. During the last two decades, different robots were invented to help in rehabilitation procedures. This paper explains the types of rehabilitation treatments and robot classifications. In addition, a few examples of well-known rehabilitation robots will be explained in terms of their efficiency and controlling mechanisms
  • 6.4K
  • 03 Nov 2020
Topic Review
Synthesis of Fragrances via Cycloaddition or Formal Cycloaddition
Fragrances, short for fragrance ingredients, is a type of compounds with a sweet smell or pleasant odor that has wide applications in the fine chemical industry, especially in perfumes, cosmetics, detergents and food additives. Since the discovery of the Diels–Alder reaction, the cycloaddition of π reactants serves as one of the most powerful methods for the construction of carbocycles, which has a broad application in the fragrance industry.
  • 6.4K
  • 21 Jun 2022
Topic Review
Frost Diagram
A Frost diagram or Frost–Ebsworth diagram is a type of graph used by inorganic chemists in electrochemistry to illustrate the relative stability of a number of different oxidation states of a particular substance. The graph illustrates the free energy vs oxidation state of a chemical species. This effect is dependent on pH, so this parameter also must be included. The free energy is determined by the oxidation–reduction half-reactions. The Frost diagram allows easier comprehension of these reduction potentials than the earlier-designed Latimer diagram, because the “lack of additivity of potentials” was confusing. The free energy ΔG° is related to reduction potential E in the graph by given formula: ΔG° = −nFE° or nE° = −ΔG°/F, where n is the number of transferred electrons, and F is Faraday constant (F = 96,485 J/(V·mol)). The Frost diagram is named after Arthur Atwater Frost (de), who originally created it as a way to "show both free energy and oxidation potential data conveniently" in a 1951 paper.
  • 6.4K
  • 01 Dec 2022
Topic Review
Interactive Movie
An interactive movie, also known as a movie game, is a video game that presents its gameplay in a cinematic, scripted manner, often through the use of full-motion video of either animated or live-action footage. In modern times, the term also refers to games that have a larger emphasis on story/presentation than on gameplay, often used in a pejorative way.
  • 6.4K
  • 04 Nov 2022
Topic Review
Soil Erosion Hazards
Soil erosion is a severe threat to food production systems globally. Food production in farming systems decreases with increasing soil erosion hazards. Hazard is a situation or potential condition to harm or threat to life, health or damage to property or environment, social and economic disruption. The mass movement of soil is an indicator of a soil erosion hazard. This includes gully erosion, riverbank erosion, rock-falls, debris-falls and landslides that can create damage to the environment and livelihoods.
  • 6.4K
  • 22 Dec 2020
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