Econstudentlog

Wikipedia articles of interest

i. 2,4-Dinitrophenol.

2,4-Dinitrophenol (DNP), C6H4N2O5, is an inhibitor of efficient energy (ATP) production in cells with mitochondria. It uncouples oxidative phosphorylation by carrying protons across the mitochondrial membrane, leading to a rapid consumption of energy without generation of ATP. […]

DNP was used extensively in diet pills from 1933 to 1938 after Cutting and Tainter at Stanford University made their first report on the drug’s ability to greatly increase metabolic rate.[3][4] After only its first year on the market Tainter estimated that probably at least 100,000 persons had been treated with DNP in the United States, in addition to many others abroad.[5] DNP acts as a protonophore, allowing protons to leak across the inner mitochondrial membrane and thus bypass ATP synthase. This makes ATP energy production less efficient. In effect, part of the energy that is normally produced from cellular respiration is wasted as heat. The inefficiency is proportional to the dose of DNP that is taken. As the dose increases and energy production is made more inefficient, metabolic rate increases (and more fat is burned) in order to compensate for the inefficiency and meet energy demands. DNP is probably the best known agent for uncoupling oxidative phosphorylation. The production or “phosphorylation” of ATP by ATP synthase gets disconnected or “uncoupled” from oxidation. Interestingly, the factor that limits ever-increasing doses of DNP is not a lack of ATP energy production, but rather an excessive rise in body temperature due to the heat produced during uncoupling. Accordingly, DNP overdose will cause fatal hyperthermia. In light of this, it’s advised that the dose be slowly titrated according to personal tolerance, which varies greatly.[6] Case reports have shown that an acute administration of 20–50 mg/kg in humans can be lethal.[7] Concerns about dangerous side-effects and rapidly developing cataracts resulted in DNP being discontinued in the United States by the end of 1938. DNP, however, continues to be used by some bodybuilders and athletes to rapidly lose body fat. Fatal overdoses are rare, but are still reported on occasion. These include cases of accidental exposure,[8] suicide,[7][9][10] and excessive intentional exposure.[9][11][12] […]

While DNP itself is considered by many to be too risky for human use, its mechanism of action remains under investigation as a potential approach for treating obesity.[19]

ii. Opium. Long article with lots of good stuff.

“The most important reason for the increase in opiate consumption in the United States during the 19th century was the prescribing and dispensing of legal opiates by physicians and pharmacists to women with ”female problems” (mostly to relieve menstrual pain). Between 150,000 and 200,000 opiate addicts lived in the United States in the late 19th century and between two-thirds and three-quarters of these addicts were women.[35] […]

After the 1757 Battle of Plassey and 1764 Battle of Buxar, the British East India Company gained the power to act as diwan of Bengal, Bihar, and Orissa (See company rule in India). This allowed the company to exercise a monopoly over opium production and export in India, to encourage ryots to cultivate the cash crops of indigo and opium with cash advances, and to prohibit the “hoarding” of rice. This strategy led to the increase of the land tax to 50% of the value of crops and to the doubling of East India Company profits by 1777. It is also claimed to have contributed to the starvation of ten million people in the Bengal famine of 1770. Beginning in 1773, the British government began enacting oversight of the company’s operations, and in response to the Indian Rebellion of 1857 this policy culminated in the establishment of direct rule over the Presidencies and provinces of British India. Bengal opium was highly prized, commanding twice the price of the domestic Chinese product, which was regarded as inferior in quality.[47]

Some competition came from the newly independent United States, which began to compete in Guangzhou (Canton) selling Turkish opium in the 1820s. Portuguese traders also brought opium from the independent Malwa states of western India, although by 1820, the British were able to restrict this trade by charging “pass duty” on the opium when it was forced to pass through Bombay to reach an entrepot.[17] Despite drastic penalties and continued prohibition of opium until 1860, opium importation rose steadily from 200 chests per year under Yongzheng to 1,000 under Qianlong, 4,000 under Jiaqing, and 30,000 under Daoguang.[48] The illegal sale of opium became one of the world’s most valuable single commodity trades and has been called “the most long continued and systematic international crime of modern times.”[49]

In response to the ever-growing number of Chinese people becoming addicted to opium, Daoguang of the Qing Dynasty took strong action to halt the import of opium, including the seizure of cargo. In 1838, the Chinese Commissioner Lin Zexu destroyed 20,000 chests of opium in Guangzhou (Canton).[17] Given that a chest of opium was worth nearly $1,000 in 1800, this was a substantial economic loss. The British, not willing to replace the cheap opium with costly silver, began the First Opium War in 1840, the British winning Hong Kong and trade concessions in the first of a series of Unequal Treaties.

Following China’s defeat in the Second Opium War in 1858, China was forced to legalize opium and began massive domestic production. Importation of opium peaked in 1879 at 6,700 tons, and by 1906, China was producing 85% of the world’s opium, some 35,000 tons, and 27% of its adult male population regularly used opium —13.5 million people consuming 39,000 tons of opium yearly.[47] From 1880 to the beginning of the Communist era, Britain attempted to discourage the use of opium in China, but this effectively promoted the use of morphine, heroin, and cocaine, further exacerbating the problem of addiction.[50] […]

iii. Metallicity.

“In astronomy and physical cosmology, the metallicity (also called Z[1]) of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium. Since stars, which comprise most of the visible matter in the universe, are composed mostly of hydrogen and helium, astronomers use for convenience the blanket term “metal” to describe all other elements collectively.[2] Thus, a nebula rich in carbon, nitrogen, oxygen, and neon would be “metal-rich” in astrophysical terms even though those elements are non-metals in chemistry. This term should not be confused with the usual definition of “metal“; metallic bonds are impossible within stars, and the very strongest chemical bonds are only possible in the outer layers of cool K and M stars. Normal chemistry therefore has little or no relevance in stellar interiors.

The metallicity of an astronomical object may provide an indication of its age. When the universe first formed, according to the Big Bang theory, it consisted almost entirely of hydrogen which, through primordial nucleosynthesis, created a sizeable proportion of helium and only trace amounts of lithium and beryllium and no heavier elements. Therefore, older stars have lower metallicities than younger stars such as our Sun.”

iv. Batavian Republic.

“The Batavian Republic (Dutch: Bataafse Republiek) was the successor of the Republic of the United Netherlands. It was proclaimed on January 19, 1795, and ended on June 5, 1806, with the accession of Louis Bonaparte to the throne of the Kingdom of Holland.” (the article has much more)

v. Taiping Rebellion. Never heard of this? You should have:

“The Taiping Rebellion was a widespread civil war in southern China from 1850 to 1864, against the ruling Manchu-led Qing Dynasty. It was led by heterodox Christian convert Hong Xiuquan, who, having claimed to have received visions, maintained that he was the younger brother of Jesus Christ [2]. About 20 million people died, mainly civilians, in one of the deadliest military conflicts in history.[3]

vi. Borobudur (featured).

Borobudur, or Barabudur, is a 9th-century Mahayana Buddhist monument in Magelang, Central Java, Indonesia. The monument consists of six square platforms topped by three circular platforms, and is decorated with 2,672 relief panels and 504 Buddha statues.[1] A main dome, located at the center of the top platform, is surrounded by 72 Buddha statues seated inside a perforated stupa.”

September 9, 2012 - Posted by | astronomy, Chemistry, Geography, history, wikipedia

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