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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.
  • 6.7K
  • 06 Jun 2022
Topic Review
Citrus limon (Lemon) Phenomenon
Citrus limon (lemon) is a species with valuable pharmaceutical, cosmetic and culinary (healthy food) properties. The valuable biological activity of C. limon is determined by its high content of phenolic compounds, mainly flavonoids (e.g., diosmin, hesperidin, limocitrin) and phenolic acids (e.g., ferulic, synapic, p-hydroxybenzoic acids). The essential oil is rich in bioactive monoterpenoids such as D-limonene, β-pinene, γ-terpinene. Recently scientifically proven therapeutic activities of C. limon include anti-inflammatory, antimicrobial, anticancer and antiparasitic activities. In view of beneficial properties C. limon  is also used in the food industry and cosmetology. Attention should be pay on safety of use and potential phototoxicity of this raw materials.
  • 6.6K
  • 30 Oct 2020
Topic Review
Pine Ridge Indian Reservation
The Pine Ridge Indian Reservation (Template:Lang-lkt), also called Pine Ridge Agency, is an Oglala Lakota Native American reservation located in the U.S. state of South Dakota. Originally included within the territory of the Great Sioux Reservation, Pine Ridge was created by the Act of March 2, 1889, 25 Stat. 888. in the southwest corner of South Dakota on the Nebraska border. Today it consists of 3,468.85 sq mi (8,984.3 km2) of land area and is the eighth-largest reservation in the United States, larger than Delaware and Rhode Island combined. The reservation encompasses the entirety of Oglala Lakota County and Bennett County, the southern half of Jackson County, and a small section of Sheridan County added by Executive Order No. 2980 of February 20, 1904. Of the 3,142 counties in the United States, these are among the poorest. Only 84,000 acres (340 km2) of land are suitable for agriculture. The 2000 census population of the reservation was 15,521; but a study conducted by Colorado State University and accepted by the United States Department of Housing and Urban Development has estimated the resident population to reach 28,787. Pine Ridge is the site of several events that mark milestones in the history between the Sioux of the area and the United States (U.S.) government. Stronghold Table—a mesa in what is today the Oglala-administered portion of Badlands National Park—was the location of the last of the Ghost Dances. The U.S. authorities' attempt to repress this movement eventually led to the Wounded Knee Massacre on December 29, 1890. A mixed band of Miniconjou Lakota and Hunkpapa Sioux, led by Chief Spotted Elk, sought sanctuary at Pine Ridge after fleeing the Standing Rock Agency, where Sitting Bull had been killed during efforts to arrest him. The families were intercepted by a heavily armed detachment of the Seventh Cavalry, which attacked them, killing many women and children as well as warriors. This was the last large engagement between U.S. forces and Native Americans and marked the end of the western frontier. Changes accumulated in the last quarter of the 20th century; in 1971 the Oglala Sioux Tribe (OST) started Oglala Lakota College, a tribal college, which offers 4-year degrees. In 1973 decades of discontent at the Pine Ridge Reservation resulted in a grassroots protest that escalated into the Wounded Knee Incident, gaining national attention. Members of the Oglala Lakota, the American Indian Movement and supporters occupied the town in defiance of federal and state law enforcement in a protest that turned into an armed standoff lasting 71 days. This event inspired American Indians across the country and gradually led to changes at the reservation, with a revival of some cultural traditions. In 1981 the Lakota Tim Giago started the Lakota Times at Pine Ridge, the first independent Native American newspaper in the nation; he published it until selling it in 1998. Located at the southern end of the Badlands, the reservation is part of the mixed grass prairie, an ecological transition zone between the short-grass and tall-grass prairies; all are part of the Great Plains. A great variety of plant and animal life flourishes on and adjacent to the reservation, including the endangered black-footed ferret. The area is also important in the field of paleontology; it contains deposits of Pierre Shale formed on the seafloor of the Western Interior Seaway, evidence of the marine Cretaceous–Paleogene boundary, and one of the largest deposits of fossils of extinct mammals from the Oligocene epoch.
  • 6.6K
  • 07 Oct 2022
Topic Review
76 Mm Gun M1
The 76 mm gun M1 was an American World War II–era tank gun developed by the U.S Ordnance Department in 1942 to supplement the 75 mm gun on the basic Medium tank M4. It was also used to arm the 76 mm Gun Motor Carriage M18 tank destroyer. Although the gun was tested in early August 1942 and classified on August 17, 1942, it was not until August 1943 that the Ordnance Department developed a mounting for the M4 tank that the tank forces would accept. It was not accepted for combat until July 1944. In January 1943, the decision was made to mount the 76 mm on the vehicle that would become the M18. By May 1944, it was being combat tested as the T70.
  • 6.6K
  • 11 Nov 2022
Topic Review
Classification of the Marine Selective Catalytic Reduction Systems
The marine SCR system is mainly composed of a urea solution injection system, mixer, SCR reactor, measurement system, and soot blowing system. The urea solution injection system is composed of a urea storage tank, urea injection pump, nozzle, valve, and pipeline. Additionally, a static mixer is arranged in the exhaust pipe of the marine SCR system to improve the mixing uniformity of exhaust gas and ammonia gas. 
  • 6.6K
  • 18 May 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.
  • 6.6K
  • 29 Jun 2021
Topic Review
Different Types of Adipocytes
Adipose tissue resides in specific depots scattered in peripheral or deeper locations all over the body and it enwraps most of the organs. This tissue is always in a dynamic evolution as it must adapt to the metabolic demand and constraints. It exhibits also endocrine functions important to regulate energy homeostasis. This complex organ is composed of depots able to produce opposite functions to monitor energy: the so called white adipose tissue acts to store energy as triglycerides preventing ectopic fat deposition while the brown adipose depots dissipate it. It is composed of many cell types. Different types of adipocytes constitute the mature cells specialized to store or burn energy. Immature adipose progenitors (AP) presenting stem cells properties contribute not only to the maintenance but also to the expansion of this tissue as observed in overweight or obese individuals.
  • 6.6K
  • 28 Apr 2021
Topic Review
Varna Necropolis
The so-called Varna Necropolis (Bulgarian: Варненски некропол) (also Varna Cemetery) is a burial site from 4569–4340 BC in the western industrial zone of Varna (approximately half a kilometre from Lake Varna and 4 km from the city centre), internationally considered one of the key archaeological sites in world prehistory. There were other necropoles dating from later Greek and Roman periods around the ancient city. The oldest gold treasure in the world, dating from this period, was discovered at the site.
  • 6.6K
  • 28 Oct 2022
Topic Review
Pharmacological Activities of Indian Camphorweed (Pluchea indica)
Pluchea indica (L.) Less. (Asteraceae) commonly-known as Indian camphorweed, pluchea, or marsh fleabane has gained great importance in various traditional medicines for its nutritional and medicinal benefits. It is utilized to cure several illnesses such as lumbago, kidney stones, leucorrhea, inflammation, gangrenous and atonic ulcer, hemorrhoids, dysentery, eye diseases, itchy skin, acid stomach, dysuria, abdominal pain, scabies, fever, sore muscles, dysentery, diabetes, rheumatism, etc. The plant or its leaves in the form of tea are commonly used for treating diabetes and rheumatism. 
  • 6.6K
  • 25 May 2022
Topic Review
Dukkha
Dukkha (/ˈduːkə/; Pāli; Sanskrit: duḥkha; Tibetan: སྡུག་བསྔལ་ sdug bsngal, pr. "duk-ngel") is an important Buddhist concept, commonly translated as "suffering", "pain", "unsatisfactoriness" or "stress". It refers to the fundamental unsatisfactoriness and painfulness of mundane life. It is the first of the Four Noble Truths. The term is also found in scriptures of Hinduism, such as the Upanishads, in discussions of moksha (spiritual liberation).
  • 6.6K
  • 24 Oct 2022
Topic Review
Royal Ordnance L7
The Royal Ordnance L7 is the basic model of the United Kingdom 's most successful tank gun. The L7 is a 105 mm L/52 rifled design by the Royal Ordnance Factories intended for use in armoured fighting vehicles, replacing the earlier 20-pounder (84 mm) tank gun mounted on the Centurion tank. The successful L7 gun has been fitted on many armored vehicles including the British Centurion (starting from the Mk. 5/2 variant), the German Leopard 1 and early variants of the US M1 Abrams (M1 and M1IP). The L7 is a popular weapon and continued in use even after it was superseded by the L11 series 120 mm rifled tank gun, for some Centurion tanks operating as Artillery Forward Observation and Armoured Vehicle, Royal Engineers (AVRE) vehicles. The L7, and adaptations of it, can be found as standard or retrofitted equipment on a wide variety of tanks developed during the Cold War.
  • 6.6K
  • 08 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.
  • 6.6K
  • 04 Nov 2022
Topic Review
Graphical Projection
Graphical projection is a protocol, used in technical drawing, by which an image of a three-dimensional object is projected onto a planar surface without the aid of numerical calculation.
  • 6.6K
  • 07 Nov 2022
Topic Review
Cost–Benefit Analysis for Road Infrastructure Projects
Cost–benefit analysis (CBA) is considered an effective evaluation method for fostering optimal decision-making and ranking of road infrastructures over decades. Eight distinct modelling categories used for CBA implementation were determined, each encompassing three different modelling approaches for capturing the data risk assessment (deterministic or probabilistic), CBA’s parameters interactive behavior (static or dynamic) and the considered economies (microeconomic or macroeconomic). In-depth content analysis led to the interpretation of the current status of extant models and the identification of three main knowledge gaps: the absence of the CBA’s inputs updating into a probabilistic environment, the deficiency of a dynamic interdependent framework and the necessity of homogenous cost datasets for road projects. Future research directions and a conceptual framework for modelling CBA into a microeconomic, probabilistic and dynamic environment are proposed providing decision-makers with new avenues for more reliable CBA modelling.
  • 6.6K
  • 29 Jan 2023
Topic Review
Mathematical Modeling and Computational Tools in Drug Design
The conventional drug discovery approach is an expensive and time-consuming process, but its limitations have been overcome with the help of mathematical modeling and computational drug design approaches. Previously, finding a small molecular candidate as a drug against a disease was very costly and required a long time to screen a compound against a specific target. The development of novel targets and small molecular candidates against different diseases including emerging and reemerging diseases remains a major concern and necessitates the development of novel therapeutic targets as well as drug candidates as early as possible. In this regard, computational and mathematical modeling approaches for drug development are advantageous due to their fastest predictive ability and cost-effectiveness features. Computer-aided drug design (CADD) techniques utilize different computer programs as well as mathematics formulas to comprehend the interaction of a target and drugs. Traditional methods to determine small-molecule candidates as a drug have several limitations, but CADD utilizes novel methods that require little time and accurately predict a compound against a specific disease with minimal cost.
  • 6.6K
  • 01 Aug 2022
Topic Review
Central Nervous System in Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a heterogeneous, behaviorally defined, neurodevelopmental disorder that has been modeled as a brain-based disease.
  • 6.6K
  • 20 Jan 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.
  • 6.6K
  • 29 Sep 2022
Topic Review
Czochralski Process
The Czochralski process is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The process is named after Polish scientist Jan Czochralski, who invented the method in 1915 while investigating the crystallization rates of metals. He made this discovery by accident: instead of dipping his pen into his inkwell, he dipped it in molten tin, and drew a tin filament, which later proved to be a single crystal. The most important application may be the growth of large cylindrical ingots, or boules, of single crystal silicon used in the electronics industry to make semiconductor devices like integrated circuits. Other semiconductors, such as gallium arsenide, can also be grown by this method, although lower defect densities in this case can be obtained using variants of the Bridgman-Stockbarger technique.
  • 6.6K
  • 24 Nov 2022
Topic Review
Antioxidants
There are established links between free radicals and more than sixty different human health conditions, including ageing, cancer, diabetes, Alzheimer’s disease, strokes, heart attacks, and atherosclerosis. Consumption of higher levels of dietary antioxidant enzymes and antioxidant molecules-enriched food or antioxidant supplements has been found to reduce the risk of free radical-related health issues. The green halotolerant microalgae Dunaliella can grow in a wide range of saline environments and is a  potential natural source for antioxidant production.
  • 6.6K
  • 10 May 2021
Topic Review
Transcription
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). Averaged over multiple cell types in a given tissue, the quantity of mRNA is more than 10 times the quantity of ncRNA (though in particular single cell types ncRNAs may exceed mRNAs). The general preponderance of mRNA in cells is valid even though less than 2% of the human genome can be transcribed into mRNA (Human genome), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: If the stretch of DNA is transcribed into an RNA molecule that encodes a protein, the RNA is termed messenger RNA (mRNA); the mRNA, in turn, serves as a template for the protein's synthesis through translation. Other stretches of DNA may be transcribed into small non-coding RNAs such as microRNA, transfer RNA (tRNA), small nucleolar RNA (snoRNA), small nuclear RNA (snRNA), or enzymatic RNA molecules called ribozymes as well as larger non-coding RNAs such as ribosomal RNA (rRNA), and long non-coding RNA (lncRNA). Overall, RNA helps synthesize, regulate, and process proteins; it therefore plays a fundamental role in performing functions within a cell. In virology, the term transcription may also be used when referring to mRNA synthesis from an RNA molecule (i.e., equivalent to RNA replication). For instance, the genome of a negative-sense single-stranded RNA (ssRNA -) virus may be a template for a positive-sense single-stranded RNA (ssRNA +)[clarification needed]. This is because the positive-sense strand contains the sequence information needed to translate the viral proteins needed for viral replication. This process is catalyzed by a viral RNA replicase.[clarification needed]
  • 6.6K
  • 14 Apr 2023
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