History.

André-Louis Debierne, a French chemist, announced the discovery of a new element in 1899. He separated it from pitchblende residues left by Marie and Pierre Curie after they had extracted radium. In 1899, Debierne described the substance as similar to titanium and (in 1900) as similar to thorium. Friedrich Oskar Giesel independently discovered actinium in 1902 as a substance being similar to lanthanum and called it "emanium" in 1904. After a comparison of the substances half-lives determined by Debierne, Harriet Brooks in 1904, and Otto Hahn and Otto Sackur in 1905, Debierne's chosen name for the new element was retained because it had seniority, despite the contradicting chemical properties he claimed for the element at different times.  Articles published in the 1970s and later suggest that Debierne's results published in 1904 conflict with those reported in 1899 and 1900. Furthermore, the now-known chemistry of actinium precludes its presence as anything other than a minor constituent of Debierne's 1899 and 1900 results; in fact, the chemical properties he reported make it likely that he had, instead, accidentally identified protactinium, which would not be discovered for another fourteen years, only to have it disappear due to its hydrolysis and adsorption onto his laboratory equipment. This has led some authors to advocate that Giesel alone should be credited with the discovery. A less confrontational vision of scientific discovery is proposed by Adloff. He suggests that hindsight criticism of the early publications should be mitigated by the then nascent state of radiochemistry: highlighting the prudence of Debierne's claims in the original papers, he notes that nobody can contend that Debierne's substance did not contain actinium. Debierne, who is now considered by the vast majority of historians as the discoverer, lost interest in the element and left the topic. Giesel, on the other hand, can rightfully be credited with the first preparation of radiochemically pure actinium and with the identification of its atomic number 89.  The name actinium originates from the Ancient Greek "aktis, aktinos" (ακτίς, ακτίνος), meaning beam or ray. Its symbol Ac is also used in abbreviations of other compounds that have nothing to do with actinium, such as acetyl, acetate and sometimes acetaldehyde.

Properties.

Actinium is a soft, silvery-white, radioactive, metallic element. Its estimated shear modulus is similar to that of lead. Owing to its strong radioactivity, actinium glows in the dark with a pale blue light, which originates from the surrounding air ionized by the emitted energetic particles. Actinium has similar chemical properties to lanthanum and other lanthanides, and therefore these elements are difficult to separate when extracting from uranium ores. Solvent extraction and ion chromatography are commonly used for the separation.  The first element of the actinides, actinium gave the group its name, much as lanthanum had done for the lanthanides. The group of elements is more diverse than the lanthanides and therefore it was not until 1945 that the most significant change to Dmitri Mendeleev's periodic table since the recognition of the lanthanides, the introduction of the actinides, was generally accepted after Glenn T. Seaborg's research on the transuranium elements (although it had been proposed as early as 1892 by British chemist Henry Bassett).  Actinium reacts rapidly with oxygen and moisture in air forming a white coating of actinium oxide that impedes further oxidation. As with most lanthanides and actinides, actinium exists in the oxidation state +3, and the Ac ions are colorless in solutions. The oxidation state +3 originates from the [Rn]6d7s electronic configuration of actinium, with three valence electrons that are easily donated to give the stable closed-shell structure of the noble gas radon. The rare oxidation state +2 is only known for actinium dihydride (AcH); even this may in reality be an electride compound like its lighter congener LaH and thus have actinium(III). Ac is the largest of all known tripositive ions and its first coordination sphere contains approximately 10.9 ± 0.5 water molecules.

Chemical compounds.

Due to actinium's intense radioactivity, only a limited number of actinium compounds are known. These include: AcF, AcCl, AcBr, AcOF, AcOCl, AcOBr, AcS, AcO and AcPO. Except for AcPO, they are all similar to the corresponding lanthanum compounds. They all contain actinium in the oxidation state +3. In particular, the lattice constants of the analogous lanthanum and actinium compounds differ by only a few percent.  Here "a", "b" and "c" are lattice constants, No is space group number and "Z" is the number of formula units per unit cell. Density was not measured directly but calculated from the lattice parameters.

Oxides.

Actinium oxide (AcO) can be obtained by heating the hydroxide at 500 °C or the oxalate at 1100 °C, in vacuum. Its crystal lattice is isotypic with the oxides of most trivalent rare-earth metals.

Halides.

Actinium trifluoride can be produced either in solution or in solid reaction. The former reaction is carried out at room temperature, by adding hydrofluoric acid to a solution containing actinium ions. In the latter method, actinium metal is treated with hydrogen fluoride vapors at 700 °C in an all-platinum setup. Treating actinium trifluoride with ammonium hydroxide at 900–1000 °C yields oxyfluoride AcOF. Whereas lanthanum oxyfluoride can be easily obtained by burning lanthanum trifluoride in air at 800 °C for an hour, similar treatment of actinium trifluoride yields no AcOF and only results in melting of the initial product.  Actinium trichloride is obtained by reacting actinium hydroxide or oxalate with carbon tetrachloride vapors at temperatures above 960 °C. Similar to oxyfluoride, actinium oxychloride can be prepared by hydrolyzing actinium trichloride with ammonium hydroxide at 1000 °C. However, in contrast to the oxyfluoride, the oxychloride could well be synthesized by igniting a solution of actinium trichloride in hydrochloric acid with ammonia.  Reaction of aluminium bromide and actinium oxide yields actinium tribromide:  and treating it with ammonium hydroxide at 500 °C results in the oxybromide AcOBr.

Other compounds.

Actinium hydride was obtained by reduction of actinium trichloride with potassium at 300 °C, and its structure was deduced by analogy with the corresponding LaH hydride. The source of hydrogen in the reaction was uncertain.  Mixing monosodium phosphate (NaHPO) with a solution of actinium in hydrochloric acid yields white-colored actinium phosphate hemihydrate (AcPO·0.5HO), and heating actinium oxalate with hydrogen sulfide vapors at 1400 °C for a few minutes results in a black actinium sulfide AcS. It may possibly be produced by acting with a mixture of hydrogen sulfide and carbon disulfide on actinium oxide at 1000 °C.

Isotopes.

Naturally occurring actinium is composed of two radioactive isotopes; (from the radioactive family of ) and (a granddaughter of ). decays mainly as a beta emitter with a very small energy, but in 1.38% of cases it emits an alpha particle, so it can readily be identified through alpha spectrometry. Thirty-six radioisotopes have been identified, the most stable being with a half-life of 21.772 years, with a half-life of 10.0 days and with a half-life of 29.37 hours. All remaining radioactive isotopes have half-lives that are less than 10 hours and the majority of them have half-lives shorter than one minute. The shortest-lived known isotope of actinium is (half-life of 69 nanoseconds) which decays through alpha decay. Actinium also has two known meta states. The most significant isotopes for chemistry are Ac, Ac, and Ac.  Purified comes into equilibrium with its decay products after about a half of year. It decays according to its 21.772-year half-life emitting mostly beta (98.62%) and some alpha particles (1.38%); the successive decay products are part of the actinium series. Owing to the low available amounts, low energy of its beta particles (maximum 44.8 keV) and low intensity of alpha radiation, is difficult to detect directly by its emission and it is therefore traced via its decay products. The isotopes of actinium range in atomic weight from 205 u () to 236 u ().

Occurrence and synthesis.

Actinium is found only in traces in uranium ores – one tonne of uranium in ore contains about 0.2 milligrams of Ac – and in thorium ores, which contain about 5 nanograms of Ac per one tonne of thorium. The actinium isotope Ac is a transient member of the uranium-actinium series decay chain, which begins with the parent isotope U (or Pu) and ends with the stable lead isotope Pb. The isotope Ac is a transient member of the thorium series decay chain, which begins with the parent isotope Th and ends with the stable lead isotope Pb. Another actinium isotope (Ac) is transiently present in the neptunium series decay chain, beginning with Np (or U) and ending with thallium (Tl) and near-stable bismuth (Bi); even though all primordial Np has decayed away, it is continuously produced by neutron knock-out reactions on natural U.  The low natural concentration, and the close similarity of physical and chemical properties to those of lanthanum and other lanthanides, which are always abundant in actinium-bearing ores, render separation of actinium from the ore impractical, and complete separation was never achieved. Instead, actinium is prepared, in milligram amounts, by the neutron irradiation of in a nuclear reactor. The reaction yield is about 2% of the radium weight. Ac can further capture neutrons resulting in small amounts of Ac. After the synthesis, actinium is separated from radium and from the products of decay and nuclear fusion, such as thorium, polonium, lead and bismuth. The extraction can be performed with thenoyltrifluoroacetone-benzene solution from an aqueous solution of the radiation products, and the selectivity to a certain element is achieved by adjusting the pH (to about 6.0 for actinium). An alternative procedure is anion exchange with an appropriate resin in nitric acid, which can result in a separation factor of 1,000,000 for radium and actinium vs. thorium in a two-stage process. Actinium can then be separated from radium, with a ratio of about 100, using a low cross-linking cation exchange resin and nitric acid as eluant.  Ac was first produced artificially at the Institute for Transuranium Elements (ITU) in Germany using a cyclotron and at St George Hospital in Sydney using a linac in 2000. This rare isotope has potential applications in radiation therapy and is most efficiently produced by bombarding a radium-226 target with 20–30 MeV deuterium ions. This reaction also yields Ac which however decays with a half-life of 29 hours and thus does not contaminate Ac.  Actinium metal has been prepared by the reduction of actinium fluoride with lithium vapor in vacuum at a temperature between 1100 and 1300 °C. Higher temperatures resulted in evaporation of the product and lower ones lead to an incomplete transformation. Lithium was chosen among other alkali metals because its fluoride is most volatile.

Applications.

Owing to its scarcity, high price and radioactivity, Ac currently has no significant industrial use, but Ac is currently being studied for use in cancer treatments such as targeted alpha therapies. Ac is highly radioactive and was therefore studied for use as an active element of radioisotope thermoelectric generators, for example in spacecraft. The oxide of Ac pressed with beryllium is also an efficient neutron source with the activity exceeding that of the standard americium-beryllium and radium-beryllium pairs. In all those applications, Ac (a beta source) is merely a progenitor which generates alpha-emitting isotopes upon its decay. Beryllium captures alpha particles and emits neutrons owing to its large cross-section for the (α,n) nuclear reaction:  The AcBe neutron sources can be applied in a neutron probe – a standard device for measuring the quantity of water present in soil, as well as moisture/density for quality control in highway construction. Such probes are also used in well logging applications, in neutron radiography, tomography and other radiochemical investigations.  Ac is applied in medicine to produce in a reusable generator or can be used alone as an agent for radiation therapy, in particular targeted alpha therapy (TAT). This isotope has a half-life of 10 days, making it much more suitable for radiation therapy than Bi (half-life 46 minutes). Additionally, Ac decays to nontoxic Bi rather than stable but toxic lead, which is the final product in the decay chains of several other candidate isotopes, namely Th, Th, and U. Not only Ac itself, but also its daughters, emit alpha particles which kill cancer cells in the body. The major difficulty with application of Ac was that intravenous injection of simple actinium complexes resulted in their accumulation in the bones and liver for a period of tens of years. As a result, after the cancer cells were quickly killed by alpha particles from Ac, the radiation from the actinium and its daughters might induce new mutations. To solve this problem, Ac was bound to a chelating agent, such as citrate, ethylenediaminetetraacetic acid (EDTA) or diethylene triamine pentaacetic acid (DTPA). This reduced actinium accumulation in the bones, but the excretion from the body remained slow. Much better results were obtained with such chelating agents as HEHA () or DOTA () coupled to trastuzumab, a monoclonal antibody that interferes with the HER2/neu receptor. The latter delivery combination was tested on mice and proved to be effective against leukemia, lymphoma, breast, ovarian, neuroblastoma and prostate cancers.  The medium half-life of Ac (21.77 years) makes it very convenient radioactive isotope in modeling the slow vertical mixing of oceanic waters. The associated processes cannot be studied with the required accuracy by direct measurements of current velocities (of the order 50 meters per year). However, evaluation of the concentration depth-profiles for different isotopes allows estimating the mixing rates. The physics behind this method is as follows: oceanic waters contain homogeneously dispersed U. Its decay product, Pa, gradually precipitates to the bottom, so that its concentration first increases with depth and then stays nearly constant. Pa decays to Ac; however, the concentration of the latter isotope does not follow the Pa depth profile, but instead increases toward the sea bottom. This occurs because of the mixing processes which raise some additional Ac from the sea bottom. Thus analysis of both Pa and Ac depth profiles allows researchers to model the mixing behavior.  There are theoretical predictions that AcH hydrides (in this case with very high pressure) are a candidate for a near room-temperature superconductor as they have T significantly higher than H3S, possibly near 250 K.

Precautions.

Ac is highly radioactive and experiments with it are carried out in a specially designed laboratory equipped with a tight glove box. When actinium trichloride is administered intravenously to rats, about 33% of actinium is deposited into the bones and 50% into the liver. Its toxicity is comparable to, but slightly lower than that of americium and plutonium. For trace quantities, fume hoods with good aeration suffice; for gram amounts, hot cells with shielding from the intense gamma radiation emitted by Ac are necessary.

Actinium is a chemical element with the symbol Ac and atomic number 89. It was first isolated by French chemist André-Louis Debierne in 1899. Friedrich Oskar Giesel later independently isolated it in 1902 and, unaware that it was already known, gave it the name emanium. Actinium gave the name to the actinide series, a group of 15 similar elements between actinium and lawrencium in the periodic table. It is also sometimes considered the first of the 7th-period transition metals, although lawrencium is less commonly given that position. Together with polonium, radium, and radon, actinium was one of the first non-primordial radioactive elements to be isolated.

锕是一种放射性金属元素,符号为Ac,原子序为89。锕在1899年被发现,是首个得到分离的非原始核素(英语:non-primordial radioactive element)。虽然钋、镭和氡比锕更早被发现,但是科学家到1902年才分离出这些元素。在元素周期表中,锕系元素始于锕,止于铹,一共有15种元素。


Definition and boundaries.

Asia–Africa boundary.

The boundary between Asia and Africa is the Red Sea, the Gulf of Suez, and

Asia–Europe boundary.

The threefold division of the Old World into Europe, Asia and Africa has been in use since the 6th century BC, due to Greek geographers such as Anaximander and Hecataeus. Anaximander placed the boundary between Asia and Europe along the Phasis River (the modern Rioni river) in Georgia of Caucasus (from its mouth by Poti on the Black Sea coast, through the Surami Pass and along the Kura River to the Caspian Sea), a convention still followed by Herodotus in the 5th century BC. During the Hellenistic period, this convention was revised, and the boundary between Europe and Asia was now considered to be the Tanais (the modern Don River). This is the convention used by Roman era authors such as Posidonius, Strabo and Ptolemy. The border between Asia and Europe was historically defined by European academics. The Don River became

Asia–Oceania boundary.

The border between Asia and the region of Oceania is usually placed somewhere in the Malay Archipelago. The Maluku Islands in Indonesia are often considered to lie on the border of southeast Asia, with New Guinea, to the east of the islands, being wholly part of

Ongoing definition.

Geographical Asia is a cultural artifact of European conceptions of the world, beginning with the Ancient Greeks, being imposed onto other cultures, an imprecise concept causing endemic contention about what it means. Asia does not exactly correspond to the cultural borders of its various types of constituents.  From the time of Herodotus a minority of geographers have rejected the three-continent system (Europe, Africa, Asia) on the grounds that there is no substantial physical separation between

Etymology.

The idea of a place called "Asia" was originally a concept of Greek civilization, though this might not correspond to the entire continent currently known by that name. The English word comes from Latin literature, where it has the same form, "Asia". Whether "Asia" in other languages comes from Latin of the Roman Empire is much less certain, and the ultimate source of the Latin word is uncertain, though several theories have been published. One of the first classical writers to use Asia as a name of the whole continent was Pliny. This metonymical change in meaning is common and can be observed in some other geographical names, such as Scandinavia (from Scania).

Bronze Age.

Before Greek poetry, the Aegean Sea area was in a Greek Dark Age, at the beginning of which syllabic writing was lost and alphabetic writing had not begun. Prior to then in the Bronze Age the records of the Assyrian Empire, the Hittite Empire and the various Mycenaean states of Greece mention a region undoubtedly Asia, certainly in Anatolia, including if not identical to Lydia. These records are administrative and do not include poetry.  The Mycenaean states were destroyed about 1200 BCE by

Classical antiquity.

Latin Asia and Greek Ἀσία appear to be the same word. Roman authors translated Ἀσία as Asia. The Romans named a province Asia, located in western Anatolia (in modern-day Turkey). There was an Asia Minor and an Asia Major located in modern-day Iraq. As the earliest evidence of the name is Greek, it is likely circumstantially that Asia came from Ἀσία, but ancient transitions, due to the lack of literary contexts, are difficult to catch in the act. The most likely vehicles were the ancient geographers and historians, such as Herodotus, who were all Greek. Ancient Greek certainly evidences early and rich uses of the name.  The first continental use of Asia is attributed to Herodotus (about 440 BCE), not because he innovated it, but because his "Histories" are the earliest surviving prose to describe it in any detail. He defines it carefully, mentioning the previous geographers whom he had read, but whose works are now missing. By it he means

History.

The history of Asia can be seen as the distinct histories of several peripheral coastal regions: East Asia, South Asia, Southeast Asia and the Middle East, linked by the interior mass of the Central Asian steppes.  The coastal periphery was home to some of the world's earliest known civilizations, each of them developing around fertile river valleys. The civilizations in Mesopotamia, the Indus Valley and the Yellow River shared many similarities. These civilizations may well have exchanged technologies and ideas such as mathematics and the wheel. Other innovations, such as writing, seem to have been developed individually in each area. Cities, states and empires developed in these lowlands.  The central steppe region had long been inhabited by horse-mounted nomads who could reach all areas of Asia from the steppes. The earliest postulated expansion out of the steppe is that of the Indo-Europeans, who spread their languages into the Middle East, South Asia, and the borders of China, where the Tocharians resided. The northernmost part of Asia, including much of Siberia, was largely inaccessible to the steppe nomads, owing to the dense forests, climate and tundra. These areas remained very sparsely populated.  The center and the peripheries were mostly kept separated by mountains and deserts. The Caucasus and Himalaya mountains

Geography and climate.

Asia is the largest continent on Earth. It covers 9% of the Earth's total surface area (or 30% of its land area), and has the longest coastline, at. Asia is generally defined as comprising the eastern four-fifths of Eurasia. It is located to the east of the Suez Canal and the Ural Mountains, and south of the Caucasus Mountains (or the Kuma–Manych Depression) and the Caspian and Black Seas. It is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean and on the north by the Arctic Ocean. Asia is subdivided into 49 countries, Five of them (Georgia, Azerbaijan, Russia, Kazakhstan and Turkey) are transcontinental countries and having part of their land in Europe.  Asia has extremely diverse climates and geographic features. Climates range from arctic and subarctic in Siberia to tropical in southern India and Southeast Asia. It is moist across southeast sections, and dry across much of the interior. Some of the largest daily temperature ranges on Earth occur in western sections of Asia. The monsoon circulation dominates across southern and eastern sections, due to the presence of the Himalayas forcing the formation of a thermal low which draws in moisture during the summer. Southwestern sections of the continent are hot. Siberia is one of the coldest places in the Northern Hemisphere, and can act as a source of arctic air masses for North America. The most active place on Earth for tropical cyclone activity lies northeast of the Philippines and south of Japan. The Gobi Desert is in Mongolia and the Arabian Desert stretches across much of the Middle East. The Yangtze River in China is the longest river in the continent. The Himalayas between Nepal and China is the tallest mountain range in the world. Tropical rainforests stretch across much of southern Asia and coniferous and deciduous forests lie farther north.

Main regions.

There are various approaches to the regional division of Asia. The following subdivision into regions is used, among others, by the UN

Climate change.

A survey carried out in 2010 by global risk analysis farm Maplecroft identified 16 countries that are extremely vulnerable to climate change. Each nation's vulnerability was calculated using 42 socio, economic and environmental indicators, which identified the likely climate change impacts during the next 30 years. The Asian countries of Bangladesh, India, Vietnam, Thailand, Pakistan and Sri Lanka were among the 16 countries facing extreme risk from climate change. Some shifts are

Economy.

Asia has the largest continental economy by both GDP Nominal and PPP in the world, and is the fastest growing economic region., the largest economies in Asia are China, Japan, India, South Korea, Indonesia and Turkey based on GDP in both nominal and PPP. Based on Global Office Locations 2011, Asia dominated the office locations with 4 of the top 5 being in Asia: Hong Kong, Singapore, Tokyo and Seoul. Around 68 percent of international firms have office in Hong Kong.  In the late 1990s and early 2000s, the economies of China and India have been growing rapidly, both with an average annual growth rate of more than 8%. Other recent very-high-growth nations in Asia include Israel, Malaysia, Indonesia, Bangladesh, Thailand, Vietnam, and the Philippines, and mineral-rich nations such as Kazakhstan, Turkmenistan, Iran, Brunei, the United Arab Emirates, Qatar, Kuwait, Saudi Arabia, Bahrain and Oman.  According to economic historian Angus Maddison in his book "The World Economy: A Millennial Perspective", India had the world's largest economy during 0 BCE and 1000 BCE. China was the largest and most advanced economy on earth for much of recorded history. For several decades in the late twentieth century Japan was the largest economy in Asia and second-largest of any single nation in the world, after surpassing the Soviet Union (measured in net material product) in 1986 and Germany in 1968. (NB: A number of supernational economies are larger, such as the European Union (EU), the North American Free Trade Agreement (NAFTA) or APEC). This ended in 2010 when China overtook Japan to become the world's second largest economy.  In the late 1980s and early 1990s, Japan's GDP was almost as large (current exchange rate method) as that of the rest of Asia combined. In 1995,

Tourism.

With growing Regional Tourism with domination of Chinese visitors, MasterCard has released Global Destination Cities Index 2013 with 10 of

Demographics.

East Asia had by far the strongest overall Human Development Index (HDI) improvement of any region in the world, nearly doubling average HDI attainment over the past 40 years, according to the report's analysis of health, education and income data. China, the second highest achiever in the world in terms of HDI improvement since 1970, is the only country on the "Top 10 Movers" list due to income rather than health or education achievements. Its per capita income increased a stunning 21-fold over the last four decades, also lifting hundreds of millions out of income poverty. Yet it was not among the region's top performers in improving school enrollment and life expectancy.
Nepal, a South Asian country, emerges as one of the world's fastest movers since 1970 mainly due to health and education achievements. Its present life expectancy is 25 years longer than in the 1970s. More than four of every five children of school age in Nepal now attend primary school, compared to just one in five 40 years ago.
 Hong Kong ranked highest among the countries grouped on the HDI (number 7 in the world, which is in the "very high human development" category), followed by Singapore (9), Japan (19) and South Korea (22). Afghanistan (155) ranked lowest amongst Asian countries out of the 169 countries assessed.

Languages.

Asia is home to several language families and many language isolates. Most Asian countries have more than one language that is natively spoken. For

Religions.

Many of the world's major religions have their origins in Asia, including the five most practiced in the world (excluding irreligion), which are Christianity, Islam, Hinduism, Chinese folk religion (classified as Confucianism and Taoism), and Buddhism respectively. Asian mythology is complex and diverse. The story of the Great Flood for example, as presented to Jews in the Hebrew Bible in the narrative of Noah—and later to Christians in the Old Testament, and to Muslims in the Quran—is earliest found in Mesopotamian mythology, in the Enûma Eliš and "Epic of Gilgamesh". Hindu mythology similarly tells about an avatar of Vishnu in the form of a fish who warned Manu of a terrible flood. Ancient Chinese mythology also tells of a Great Flood spanning generations, one that required the combined efforts of emperors and divinities to control.

Abrahamic.

The Abrahamic religions including Judaism, Christianity, Islam and Bahá'í Faith originated in West Asia.  Judaism, the oldest of the Abrahamic faiths, is practiced primarily in Israel, the indigenous homeland and historical birthplace of the Hebrew nation: which today consists both of those Jews who remained in the Middle East and those who returned from diaspora in Europe, North America, and other regions; though various diaspora communities persist worldwide. Jews are the predominant ethnic group in Israel (75.6%) numbering at about 6.1 million, although the levels of adherence to Jewish religion vary. Outside of Israel there are small ancient Jewish communities in Turkey (17,400), Azerbaijan (9,100), Iran (8,756), India (5,000) and Uzbekistan (4,000), among many other places. In total, there are 14.4–17.5 million (2016, est.) Jews alive in the world today, making them one of the smallest Asian minorities, at roughly 0.3 to 0.4 percent of the total population of the continent.  Christianity is a widespread religion in Asia with more than 286 million adherents according to Pew Research Center in 2010, and nearly 364 million according to Britannica Book of

Indian and East Asian religions.

Almost all Asian religions have philosophical character and Asian philosophical traditions cover a large spectrum of philosophical thoughts and writings. Indian philosophy includes Hindu philosophy and Buddhist philosophy. They include elements of nonmaterial pursuits, whereas another school of thought from India, Cārvāka, preached the enjoyment of the material world. The religions of Hinduism, Buddhism, Jainism and Sikhism originated in India, South Asia. In East Asia, particularly in China and Japan, Confucianism, Taoism and Zen Buddhism took shape. , Hinduism has around 1.1 billion adherents. The faith represents around 25% of Asia's population and is the largest religion in Asia. However, it is mostly concentrated in South Asia. Over 80% of the populations of both India and Nepal adhere to Hinduism, alongside significant communities in Bangladesh, Pakistan, Bhutan, Sri Lanka and Bali, Indonesia. Many overseas Indians in countries such as Burma, Singapore and

Modern conflicts.

Some of the events pivotal in the Asia territory

Culture.

Nobel prizes.

The polymath Rabindranath Tagore, a Bengali poet, dramatist, and writer from Santiniketan, now in West Bengal, India, became in 1913 the first Asian Nobel laureate. He won his Nobel Prize in Literature for notable impact his prose works and poetic thought had on English, French, and other national literatures of Europe and the Americas. He is also the writer of the national anthems of Bangladesh and India.  Other Asian writers who won Nobel Prize for literature include Yasunari Kawabata (Japan, 1968), Kenzaburō Ōe (Japan, 1994), Gao Xingjian (China, 2000), Orhan Pamuk (Turkey, 2006), and Mo Yan (China, 2012). Some may consider the American writer, Pearl S. Buck, an honorary Asian Nobel

Political geography.

Within the above-mentioned states are several partially recognized countries

See also.

References to articles:  Special topics:  Lists:  Projects

Asia () is Earth's largest and most populous continent, located primarily in the Eastern and Northern Hemispheres. It shares the continental landmass of Eurasia with the continent of Europe and the continental landmass of Afro-Eurasia with both Europe and Africa. Asia covers an area of, about 30% of Earth's total land area and 8.7% of the Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilizations. Asia is notable for not only its overall large size and population, but also dense and large settlements, as well as vast barely populated regions. Its 4.5 billion people () constitute roughly 60% of the world's population.

亚细亚洲(;),简称亚洲,面积4457.9万平方公里,约占地球总面积的8.6%(总陆地面积的29.4%);亚洲人口约47亿人,是世界总人口约61%(2019年);是七大洲中面积最大,人口最多的一个洲。


Biography.

Origins and early career.

Avitus was born in Clermont to a family of the Gallo-Roman nobility. His father was possibly Flavius Julius Agricola, consul in 421. Avitus had two sons, Agricola (fl 455 – living 507, a "vir illustris") and Ecdicius Avitus (later "patricius" and "magister militum" under Emperor Julius Nepos) and a daughter Papianilla; she married Sidonius Apollinaris, whose letters and panegyrics remain an important source for Avitus' life and times.  Avitus followed a course of study typical for a young man of his rank, including law. Before 421 he was sent to the powerful "patricius" Flavius Constantius (briefly Emperor in 421) to ask for a tax reduction for his own country; this embassy was successful. His relative Theodorus was hostage at the court of the King of Visigoths, Theodoric I. In 425/426 Avitus went and met him and the King, who let Avitus enter his own court. Here, around 439, Avitus met the son of Theodoric, Theodoric II, who later became King. Avitus inspired the young Theodoric to study Latin poets.  He then started a military career serving under the "magister militum" Aetius in his campaign against the Juthungi and the Norics (430–431) and against the Burgundians (436). In 437, after being elevated to the rank of "vir illustris", he returned to Avernia, where he held a high office, probably "magister militum per Gallias". In the same year he defeated a group of Hunnic raiders near Clermont and obliged Theodoric to lift the siege of Narbonne. In 439 he became Praetorian prefect of Gaul and renewed the friendship treaty with the Visigoths.  Before the summer of 440, he retired to private life at his estate, "Avitacum", near Clermont. Here he lived until 451 when the Huns, led by Attila, invaded the Western Roman Empire; Avitus persuaded Theodoric into an alliance with Rome, and the combined forces of Theodoric and Aetius defeated Attila in the Battle of Châlons; Theodoric died in the battle.

Rise to the throne.

In the late spring of 455, Avitus was recalled to service by emperor Petronius Maximus and was elevated to the rank of "magister militum", probably "praesentalis"; Maximus sent Avitus in an embassy to the court of Theodoric II, who had succeeded to his father, at Toulouse. This embassy probably confirmed the new king and his people as "foederati" of the Empire and asked for their support for the new Emperor.  While Avitus was at Theodoric's court, news came of the death of Petronius Maximus (31 May) and of the sack of Rome by the Vandals of Gaiseric. Theodoric acclaimed Avitus Emperor in Toulouse; on 9 July, the new Emperor was acclaimed by the Gallic chiefs gathered in "Viernum" (near Arles), near Arelate (Arles), and later, around 5 August, before Avitus reached Rome, he received the recognition of the Roman Senate.  Avitus stayed in Gaul for three months, to consolidate his power in the region that was the center of his support, and later went to Italy with a Gallic army, probably reinforced with a Gothic force. He probably travelled to Noricum to restore the imperial authority in that province, and then passed through Ravenna, where he left a Gothic force under the new "patricius" and "magister militum" Remistus, a Visigoth. On 21 September, finally, he entered Rome.

Consolidation of power.

The effective power of Avitus depended on the support of all the major players in the Western Roman Empire in the mid-5th century. The new Emperor needed the support of both the civil institutions, the Roman senate and the Eastern Roman Emperor Marcian, as well as that of the army and its commanders (the generals Majorian and Ricimer) and the Vandals of Gaiseric.  On 1 January 456, Avitus took the consulate, as traditionally the Emperors held the consulate in the first year upon assuming the purple. However, his consulate "sine collega" (without a second Consul) was not recognised by the Eastern court, which nominated two consuls, Iohannes and Varanes. The fact that the two courts did not agree on a couple of consuls but each nominated its own means that despite the efforts of Avitus to receive the recognition of the Eastern Emperor, the relationship between the two halves of the Empire was not optimal.

Foreign policy.

Treaties under Marcian and a treaty of 442 between emperor Valentinian III and the Vandal king Gaiseric had failed to reduce Vandal incursions and raids along the Italian coast. Avitus' own efforts secured a temporary winter truce with them; but in March 456, Vandals destroyed Capua. Avitus sent Ricimer to defend Sicily, and the Romans defeated the Vandals twice, once in a land battle near Agrigento and another in a naval battle off Corsica.  During the reign of Avitus, the Visigoths expanded into Hispania, nominally under Roman authorisation but actually to promote their own interests. In 455 Avitus had sent an ambassador, "comes" Fronto, to the Suebi and then to Theodoric II to ask them to formally recognise Roman rule. When the Suebi invaded the Roman province of Hispania Tarraconensis, the Visigoths attacked and defeated them 5 October 456 at the Campus Paramus, twelve miles from Astorga, on the banks of the Órbigo (Urbicus), subsequently occupying the province as nominal "foederati" of the Empire.

Fall.

In the meantime, resentment amongst the population of Italy against the foreigner Avitus grew. The Gallo-Roman Emperor had given to other members of the Gallo-Roman aristocracy many key offices of the public administration usually filled by Romans. Furthermore, the population of Rome, devastated by the sack of Rome, suffered from food shortages due to the Vandal control of the naval routes, aggravated by the requirements of the foreign troops that had arrived with Avitus. The imperial treasury was almost empty and, after disbanding his Visigoth guard because of popular pressure, Avitus was obliged to pay their huge wages by melting down and selling the bronze of some statues.  Counting on the popular discontent, on the disbandment of the imperial guard, and on the prestige gained through their victories, Ricimer and the "comes domesticorum" Majorian rebelled against Avitus; the Emperor was obliged to leave Rome in early autumn and to move north. Ricimer had the Roman Senate depose Avitus and ordered the murder of the "magister militum" Remistus in the "Palatium" at Classe, ancient port of Ravenna, on 17 September 456.  Avitus decided to react. First he chose Messianus, one of his collaborators in his embassy to the Visigoths ordered by Petronius Maximus, as the new "magister militum"; then he probably went to Gaul (Hydatius says to Arelate) to collect all the available forces, probably the Visigoth guard he had just disbanded; finally he led his forces against the troops of Ricimer, near Piacenza. The Emperor and his army entered the city and attacked the huge army led by Ricimer, but after a great massacre of his men, including Messianus, Avitus fled on 17 or 18 October 456. In the immediate aftermath Ricimer spared his life, but forced him to become Bishop of Piacenza.

Death.

Avitus' Gallic supporters may still have recognised him as emperor, despite his deposition. Sidonius Apollinaris tells of a failed "coup d'état" in Gaul organised by one Marcellus and probably aimed at bringing Avitus back on the throne. The contemporary historian Hydatius, who lived in Spain, considered the year 457 the third of Avitus' reign; Avitus' own intentions are not known, nor are the manner and date of his death, of which there are several versions. In some, he was told that the Roman Senate had condemned him to death, and so he tried to flee to Gaul, officially travelling there to bring donations to the basilica of Saint Julian in Avernia, his homeland; according to Gregory of Tours, he died during this journey. Other sources have him strangled or starved to death, by order of his successor. Avitus died in 457, or late in 456, very soon after his deposition, and was buried at Brioude, next to Saint Julian's tomb.

Bibliography.

Primary sources.

Major source for Avitus' life until his rise to the throne is the panegyric written in occasion of his consulate by Sidonius Apollinaris (431–486):  For the history of his reign, the major sources are the Spaniard historian Hydatius (400 c. – 469 c.) and the Byzantine chronicler John of Antioch (first half of the 7th century):

Marcus Maecilius Flavius Eparchius Avitus c. 380/395 – after 17 October 456 or in 457) was Western Roman Emperor from 8 or 9 July 455 to 17 October 456. He was a senator and a high-ranking officer both in the civil and military administration, as well as Bishop of Piacenza.

阿维图斯(Eparchius Avitus,385年—456年或457年),罗马帝国西部的皇帝(455年-456年在位)。


History.

The shell terminology comes from Arnold Sommerfeld's modification of the Bohr model. Sommerfeld retained Bohr's planetary model, but added mildly elliptical orbits (characterized by additional quantum numbers "" and "m") to explain the fine spectroscopic structure of some elements. The multiple electrons with the same principal quantum number ("n") had close orbits that formed a "shell" of positive thickness instead of the infinitely thin circular orbit of Bohr's model.  The existence of electron shells was first observed experimentally in Charles Barkla's and Henry Moseley's X-ray absorption studies. Barkla labeled them with the letters K, L, M, N, O, P, and Q. The origin of this terminology was alphabetic. A "J" series was also suspected, though later experiments indicated that the K absorption lines are produced by the innermost electrons. These letters were later found to correspond to the "n" values 1, 2, 3, etc. They are used in the spectroscopic Siegbahn notation.

Subshells.

Each shell is composed of one or more subshells, which are themselves composed of atomic orbitals. For example, the first (K) shell has one subshell, called ; the second (L) shell has two subshells, called and ; the third shell has,, and ; the fourth shell has,, and ; the fifth shell has,,, and and can theoretically hold more in the subshell that is not occupied in the ground-state electron configuration of any known element. The various possible subshells are shown in the following table:

Number of electrons in each shell.

Each subshell is constrained to hold electrons at most, namely:  Therefore, the K shell, which contains only an subshell, can hold up to 2 electrons; the L shell, which contains an and a, can hold up to 2 + 6 = 8 electrons, and so forth; in general, the "n"th shell can hold up to 2"n" electrons.  Although that formula gives the maximum in principle, in fact that maximum is only "achieved" (by known elements) for the first four shells (K, L, M, N). No known element has more than 32 electrons in any one shell. This is because the subshells are filled according to the Aufbau principle. The first elements to have more than 32 electrons in one shell would belong to the g-block of period 8 of the periodic table. These elements would have some electrons in their subshell and thus have more than 32 electrons in the O shell (fifth principal shell).

Subshell energies and filling order.

Although it is sometimes stated that all the electrons in a shell have the same energy, this is an approximation. However, the electrons in one "subshell" do have exactly the same level of energy, with later subshells having more energy per electron than earlier ones. This effect is great enough that the energy ranges associated with shells can overlap.  The filling of the shells and subshells with electrons proceeds from subshells of lower energy to subshells of higher energy. This follows the "n + l rule" which is also commonly known as the Madelung rule. Subshells with a lower "n + l" value are filled before those with higher "n + l" values. In the case of equal "n + l" values, the subshell with a lower "n" value is filled first.

List of elements with electrons per shell.

The list below gives the elements arranged by increasing atomic number and shows the number of electrons per shell. At a glance, the subsets of the list show obvious patterns. In particular, every set of five elements (in ) before each noble gas (group 18, in ) heavier than helium have the number of electrons in the outermost shell in arithmetic progression, namely three to seven. (However, this pattern may break down in the seventh period due to relativistic effects.)  Sorting the table by chemical group shows additional patterns, especially with respect to the last two outermost shells. (Elements 57 to 71 belong to the lanthanides, while 89 to 103 are the actinides.)  The list below is primarily consistent with the Aufbau principle. However, there are a number of exceptions to the rule; for example palladium (atomic number 46) has no electrons in the fifth shell, unlike other atoms with "lower" atomic number. Some entries in the table are uncertain, when experimental data is unavailable. (For example, the elements past 108 have such short half-lives that their electron configurations have not yet been measured.)

In chemistry and atomic physics, an electron shell may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called the " shell" (also called the "K shell"), followed by the " shell" (or "L shell"), then the " shell" (or "M shell"), and so on farther and farther from the nucleus. The shells correspond to the principal quantum numbers ("n" = 1, 2, 3, 4...) or are labeled alphabetically with the letters used in X-ray notation (K, L, M,...).

电子层,或称电子壳或电子壳层,是原子物理学中,一组拥有相同主量子数"n"的原子轨道。电子层组成为一粒原子的电子序。这可以证明电子层可容纳最多电子的数量为formula_1(但倒数第一层只能容纳2个,倒数第二层只能容纳8个,倒数第三层只能容纳18个),这种全满的电子层称为「闭合壳层」。


Family.

Ashurnasirpal II's father was Tukulti-Ninurta II. His son and successor was Shalmaneser III. His queen was Mullissu-mukannišat-Ninua.

Reign.

The palaces, temples and other buildings raised by him bear witness to a considerable development of wealth and art. He was renowned for his brutality, using enslaved captives to build a new Assyrian capital at Kalhu (Nimrud) in Mesopotamia where he built many impressive monuments. He was also a shrewd administrator, who realized that he could gain greater control over his empire by installing Assyrian governors, rather than depending on local client rulers paying tribute.

Campaigns.

Like previous Assyrian monarchs Ashurnasirpal campaigned along the Euphrates against Aramaeans and in the Diyala against Babylon. Ashurnasirpal II's brutal treatment of rebels ensured that even when his army was not present, there would not be further revolts. Further revolts would see the local monarch replaced with a governor loyal only to the Assyrian monarchy. Leading his army, which was typically composed of infantry (including auxiliaries and foreigners), heavy & light cavalry and chariots, Ashurnasirpal conquered the Hittites and Aramaean states of northern Syria.  Ashurnasirpal II did not destroy the Phoenician/Canaanite cities he conquered. He was unsuccessful in his siege of Tyre, which under Ittobaal settled Kition in Cyprus and opened up trade routes throughout the Aegean, at Rhodes and Miletus. Through tribute they became sources for the raw materials of his armies and his building programs. Iron was needed for weapons, Lebanese cedar for construction and gold and silver for the payment of troops.  When considering the occupied citizens of his conquered territories, he wrote; I resettled them in their abandoned towns and houses. I imposed more tribute and tax on them then ever before: horses, mules, oxen, sheep, wine and labor.

Palace of Kalhu.

Ashurnasirpal II's palace was built and completed in 879 BC in Kalhu, which is in modern-day Iraq slightly north of Baghdad. The palace walls were lined with reliefs carved in alabaster. These reliefs bore elaborate carvings, many portraying the king surrounded by winged protective spirits, or engaged in hunting or on campaign. Each also had text inscribed in it. This text was the same or very similar on each relief and is therefore called the Standard Inscription. The Standard Inscription begins by tracing Ashur-nasir-pal II's lineage back three generations and recounts his military victories, defines the boundaries of his empire, tells how he founded Kalhu, and built the palace. Ashurnasirpal II also built a massive gateway at Nimrud.  The British archaeologist A.H. Layard excavated Kalhu in the 1840s, uncovering the North-West Palace of Ashurnasirpal II. Today, many of the reliefs and sculptures from the excavations in Nimrud are displayed in the galleries of the British Museum, London, including the Statue of Ashurnasirpal II and the Black Obelisk, with other reliefs on display in museums in Europe (e.g. Munich), Japan and the USA.

Nimrud reliefs.

After Assyria fell in 612 BC, the palace became overgrown and eventually completely buried, in which state it remained for nearly 2,500 years until rediscovered by the British born Austen Henry Layard in 1845. Layard oversaw the excavation of the palace during which time the reliefs that dominated the walls of the structure were removed from the site and sent to collections throughout Europe and North America, with the British Museum receiving the majority of these Nimrud reliefs. Despite excavating and removing many of these reliefs, a great number remained within the palace and were eventually reburied with time. In 1949 M.E.L. Mallowan re-excavated the site, which lasted until 1957, at which time the project was taken over by the Iraq Department of Antiques which still remains in control of the site. The known area of the palace measures 200m from north to south and 120 meters from east to west. This is most likely only a portion of the original design, including the possibility of an upper level while no concrete evidence of this remains. All of the walls of the palace were lined with stone slabs of which a majority were decorated with relief images.

Symbolism and purpose.

Among these relief images occurred a certain amount of standardization around 870 BC. Carved into each of the stone slabs, including the ones lacking relief, was what is referred to as the Standard Inscription. This text gave the various names and titles of the king, spoke of his relationship with the gods and summarized his military conquests. The text also goes on to describe the founding of Kalhu and speaks of the palace itself. The slabs, which contain relief, consist of depictions of Assurnasirpal's royal ideology. This ideology can be categorized into four main ideas, the military success of the king, his service to the gods, which provided divine protection and Assyrian prosperity. There is a particular interest in the anatomy of both humans and animals within the depictions. Royal hunting scenes are some of the most well known of the Nimrud reliefs particularly those showing Assurnasirpal II hunting lions. There is also a distinct interest in the relationship between man and animal in many of the scenes. In several depictions the king is shown with supernatural creatures of animal and human combination. All of the apotropaic portrayals, which would have decorated the doorways of the palace, were of these human and animal hybrids. Within the context of these apotropaic figures were three main types, a winged figure wearing the horned crown which symbolized divinity, a winged figure wearing a headband of rosettes and a winged human figure with the head of a bird.

Recurring subject matter.

Other popular themes in the Nimrud reliefs included military campaigns and victories garnered by the Assyrians. More specifically these were displays of the relationships between Assyrians and non-Assyrians. The Assyrians were always shown in moments of glory while the non-Assyrians are in sprawled or contorted positions and most often naked. These illustrations represented violent death as punishment for violating Assyrian values, as well as merciless punishment for transgressions. Not only would this have served as a clear message for visiting dignitaries from other cultures but also the same message was innately obvious as a warning to the Assyrian elites as to what could happen if they decided to defy the king. Non-elites were likely not viewing these reliefs in that they would not have often, if ever, been permitted into the palace. The elites would have typically only been present at the palace for rituals and other business with the king. Assyrian women tend to be absent from all of these relief sculptures. This is most likely due to the context of the reliefs, which were male dominated activities. The only exception to women being absent from these scenes would be in the case of non-Assyrian women who were captured as slaves during war. These were typically the elite women of other cultures rather than the lower class. In contrast to the way in which male captives were portrayed, women were neither bound nor naked in their depictions. Women captives were most often shown in floor length outfits with possibly one part of their body exposed in detail.

Site post-excavations.

Not all of the relief sculptures have been removed from the palace at Nimrud, with many of them still able to be viewed in their original context although this is greatly limited. Many of the museums, which currently display the Nimrud reliefs, attempt to recreate the palace atmosphere by exhibiting them in a similar fashion to their original loci.  In November 2014, it was reported that ISIL (Islamic State of Iraq and the Levant) militants had looted many of Iraq's archaeological sites, including the palace of Ashurnasirpal II, and are selling artifacts on the black market. According to Aymen Jawad, executive director of Iraq Heritage (based in London), ""Tablets, manuscripts and cuneiforms are the most common artifacts being traded, and, unfortunately, this is being seen in Europe and America,”" he says. "“Hundreds of millions of dollars’ worth of irreplaceable pieces are being sold to fund terrorists.""  On 5 March 2015 ISIL reportedly started the demolition of Nimrud. The local palace was bulldozed, while lamassu statues at the gates of the palace of Ashurnasirpal II were smashed.

Current location of Nimrud reliefs.

United States United Kingdom Europe Middle East  <br

Ashur-nasir-pal II (transliteration: "Aššur-nāṣir-apli", meaning "Ashur is guardian of the heir") was king of Assyria from 883 to 859 BC.

阿淑尔纳西尔帕二世(音译"Aššur-nâṣir-apli",意为“亚述继承人的守卫者”)(?-前859年),是一位亚述国王(公元前883年-公元前859年)。


History.

1960s.

Amnesty International was founded in London in July 1961 by English labour lawyer Peter Benenson along with Professor of Law and friend Philip James. According to Benenson's own account, he was travelling on the London Underground on 19 November 1960 when he read that two Portuguese students from Coimbra had been sentenced to seven years of imprisonment in Portugal for allegedly "having drunk a toast to liberty". Researchers have never traced the alleged newspaper article in question. In 1960, Portugal was ruled by the Estado Novo government of António de Oliveira Salazar. The government was authoritarian in nature and strongly anti-communist, suppressing enemies of the state as anti-Portuguese. In his significant newspaper article "The Forgotten Prisoners", Benenson later described his reaction as follows: Open your newspaper any

1970s.

During the 1970s, Seán MacBride and Martin Ennals led Amnesty International. While continuing to work for prisoners of conscience, Amnesty International's purview widened to include "fair trial" and opposition to long detention without trial (UDHR Article 9), and especially to the torture of prisoners (UDHR Article 5). Amnesty International believed that the reasons underlying torture of prisoners by governments, were either to acquire and obtain information or to quell opposition by the use of terror, or both. Also of concern was the export of more sophisticated torture methods, equipment and teaching by the superpowers to "client states", for example by the United States through some activities of the CIA.  Amnesty International drew together reports from countries where torture allegations seemed most persistent and organized an international conference on torture. It sought to influence public opinion to put pressure on national governments by organizing a campaign for the "Abolition of Torture", which ran for several years.  Amnesty International's membership increased from 15,000 in 1969 to 200,000 by 1979. This growth in resources enabled an expansion of its program, "outside of the prison walls", to include work on "disappearances", the death penalty

1980s.

By 1980, Amnesty International was drawing more criticism from governments. The Soviet Union alleged that Amnesty International conducted espionage, the Moroccan government denounced it as a defender of lawbreakers, and the Argentinian government banned Amnesty International's 1983 annual report.  Throughout the 1980s, Amnesty International continued to campaign against torture, and on behalf of prisoners of conscience. New issues emerged, including extrajudicial killings, military, security and police transfers, political killings, and disappearances.  Towards the end of the decade, the growing number of refugees worldwide became a focus for Amnesty International. While many of the world's refugees of the time had been displaced by war and famine, in adherence to its

1990s.

Throughout the 1990s, Amnesty continued to grow, to a membership of over seven million in over 150 countries and territories, led by Senegalese Secretary General Pierre Sané. Amnesty continued to work on a wide range of issues and world events. For example, South African groups joined in 1992 and hosted a visit by Pierre Sané to meet with the apartheid government to press for an investigation into allegations of police abuse, an end to arms sales to the African Great Lakes region and the abolition of the death penalty. In particular, Amnesty International brought attention

2000s.

After 2000, Amnesty International's primary focus turned to the challenges arising from globalization and the reaction to the 11 September 2001 attacks in the United States. The issue of globalization provoked a major shift in Amnesty International policy, as the scope of its work was widened to include economic, social and cultural rights, an area that it had declined to work on in the past. Amnesty International felt this shift was important, not just to give credence to its principle of the indivisibility of rights, but because of what it saw as the growing power of companies and the undermining of many nation states as a result of globalization.  In the aftermath of 11 September attacks, the new Amnesty International Secretary General, Irene Khan, reported that a senior government official had said to Amnesty International delegates: "Your role collapsed with the collapse of the Twin Towers in New York." In the years following the attacks, some believe that the gains made by human rights organizations over previous decades had possibly been eroded. Amnesty International argued that human rights were the basis for the

2010s.

2010.

In February 2010, Amnesty suspended Gita Sahgal, its gender unit head, after she criticized Amnesty for its links with Moazzam Begg, director of Cageprisoners. She said it was "a gross error of judgment" to work with

2011.

In February 2011, Amnesty requested that Swiss authorities start a criminal investigation of former US President George W. Bush and arrest him.  In July 2011, Amnesty International celebrated

2012.

In August 2012, Amnesty International's chief executive in India sought an impartial

2014.

On 18 August 2014, in the wake of demonstrations sparked by people protesting the fatal police shooting of Michael Brown, an unarmed 18-year-old man, and subsequent acquittal of Darren Wilson, the officer who shot him, Amnesty International sent a 13-person contingent of human rights

2016.

In February 2016, Amnesty International launched its annual report of human rights around the world titled "The State of the World's Human Rights". It warns from the consequences of "us vs them" speech which divided human beings into two camps. It states that this speech enhances a global pushback against human rights and makes the world more divided and more dangerous. It also states that in 2016, governments turned a blind eye to war crimes and passed laws that violate free expression. Donald Trump signed an executive order in an attempt to prevent refugees from seeking resettlement in

2017.

Amnesty International published its annual report for the year 2016–2017 on 21 February 2017. Secretary General Salil Shetty's opening statement in the report highlighted many ongoing international abuses as well as emerging threats. Shetty drew attention, among many issues, to the Syrian Civil War, the use of chemical weapons in the War in Darfur, outgoing United States President Barack Obama's expansion of drone warfare, and the successful 2016 presidential election campaign of Obama's successor Donald Trump. Shetty stated that the Trump election campaign was characterized by "poisonous" discourse in which "he frequently made deeply divisive statements marked by misogyny and xenophobia, and pledged to roll back established civil liberties

2018.

Amnesty International published its 2017/2018 report in February 2018.  In October 2018, an Amnesty International researcher was abducted and beaten while observing demonstrations in Magas, the capital of Ingushetia, Russia.  On 25 October, federal officers raided the Bengaluru office for 10 hours on a suspicion that the organization had violated foreign direct investment guidelines on the orders of the Enforcement Directorate. Employees and supporters of Amnesty International say this is an act to intimidate organizations and people who question the authority and capabilities of government leaders. Aakar Patel, the Executive Director of the Indian branch claimed, "The Enforcement Directorate's raid on our office today shows how the authorities are now treating human rights organizations like criminal enterprises, using heavy-handed methods. The current Prime Minister of India, Narendra Modi, has been criticized for harming civil society in India, specifically by targeting advocacy groups. Modi has cancelled the registration of about 15,000

2019.

In February 2019, Amnesty International's management team offered to resign after an independent report found what it called a "toxic culture" of workplace bullying, and found evidence of bullying, harassment, sexism and racism, after being asked to investigate the suicides of 30-year Amnesty veteran Gaetan Mootoo in Paris in May 2018 (who left a note citing work pressures), and 28-year-old intern Rosalind McGregor in Geneva in July 2018.  In April 2019, Amnesty International's deputy director for research in Europe, Massimo Moratti, warned that if extradited to the United States, WikiLeaks founder Julian Assange would face the "risk of serious human rights violations, namely detention conditions, which could violate the prohibition of torture".  On 24 April 2019 an alliance of different groups of Kurdish activists occupied the reception of Amnesty's London offices, to protest against Amnesty's inaction in ignoring the human rights abuses against Kurds in Turkey, including the incarceration and isolation of their leader, Abdullah Øcalan. There were claims that Amnesty's inaction had been driven by undue deference to the Turkish and Qatari regimes. A hunger strike was declared by the occupiers. On 26 April Amnesty called on the Police forcibly to eject the demonstrators, and the offices were cleared. There was subsequent public criticism of this action.  On May 14, 2019, Amnesty International filed a petition with the District Court of Tel Aviv, Israel, seeking a revocation of the export license of surveillance technology firm NSO Group. The filing states

Structure.

Amnesty International is largely made up of voluntary members, but retains a small number of paid professionals. In countries in which Amnesty International has a strong presence, members are organized as "sections". Sections co-ordinate basic Amnesty International activities normally with a significant number of members, some of whom will form into "groups", and a professional staff. Each have a board of directors. In 2019 there were 63 sections worldwide. "Structures" are aspiring sections. They also co-ordinate basic activities but have a smaller membership and a limited staff. In countries where no section or structure exists, people can become "international members". Two other organizational models exist: "international networks", which promote specific themes or have a specific identity, and "affiliated groups", which do the same work as section groups, but in isolation.  The highest governing body is the Global Assembly which meets annually. Each Section sends its Chair and Executive Director to the GA. The GA process is governed and managed by the PrepCom (Preparatory Committee).  The International Board (formerly known as the International Executive Committee [IEC]), led by the International Board Chairperson (Sarah Beamish) consists of nine members and the International Treasurer. Two members are co-opted.  The IB is elected by, and accountable to, the Global Assembly. The International Board meets at least two times during any one year and in practice meets face to face at least four times a year. Other board and sub committee meetings are undertaken via video conferencing.  The role of the International Board is to take decisions on behalf of Amnesty International, govern the International Secretariat including regional offices, implement the strategy laid out by the Global Assembly and ensure compliance with the organization's statutes.  The International Secretariat (IS) is responsible for the conduct and daily affairs of Amnesty International under direction from the International Board. It is run by approximately 500 professional staff members and is headed by a Secretary General. The Secretariat operates several work programmes; International Law and Organizations; Research; Campaigns; Mobilization; and Communications. Its offices have been located in London since its establishment in the mid-1960s.

Charitable status.

In the UK Amnesty International has two principal arms, Amnesty International

Principles.

The core principle of Amnesty International is a focus on prisoners of conscience, those persons imprisoned or prevented from expressing an opinion by means of violence. Along with this commitment to opposing repression of freedom of expression, Amnesty International's founding principles included non-intervention on political questions, a robust commitment to gathering facts about the various cases and promoting human rights.  One key issue in the principles is in regards to those individuals who may advocate or tacitly support resorting to violence in struggles against repression. AI does not judge whether recourse to violence is justified or not. However, AI does not oppose the political use

Objectives.

Amnesty International primarily targets governments, but also reports on non-governmental bodies and private individuals ("non-state actors").  There are six key areas which Amnesty deals with:  Some specific aims are to: abolish the death penalty, end extra judicial executions and "disappearances", ensure prison conditions meet international human rights standards, ensure prompt and fair trial for all political prisoners, ensure free education to all children worldwide, decriminalize abortion, fight impunity from systems of justice, end the recruitment and use of child soldiers, free all prisoners of conscience, promote economic, social and cultural rights for marginalized communities, protect human rights defenders, promote religious tolerance, protect LGBT rights, stop torture and ill-treatment, stop unlawful killings in armed conflict, uphold the rights of refugees, migrants, and asylum seekers, and protect human dignity. It also supports worldwide decriminalisation of prostitution. Additionally, Amnesty International has developed ways to publicize information and mobilize public opinion. The organization considers the publication of impartial and accurate reports as one of its strengths. Reports are researched by: interviewing victims and officials, observing trials, working with local human rights activists, and monitoring the media. It aims to issue timely press releases and publishes information in newsletters and on web sites. It also sends official missions to countries to make courteous but insistent inquiries.  Campaigns to mobilize public opinion can take the form of individual, country, or thematic campaigns. Many techniques are deployed, such as direct appeals (for example, letter writing), media and publicity work, and public demonstrations. Often, fund-raising is integrated with campaigning. In 2018, the organization started to adopt a new communications strategy based on a message of shared humanity and a hope-based communications approach.  In situations which require immediate attention, Amnesty International calls on existing urgent action networks or crisis response networks; for all other matters, it calls on its membership. It considers the large size of its human resources to be another of its key strengths.  The role of Amnesty International has a significant impact on getting citizens on board with focusing on human rights issues. These groups influence countries and governments to give their people justice with pressure and in human resources. An example of Amnesty International's work is writing letters to free imprisoned people that were put there for non-violent expressions. The group now has power, attends sessions, and became a source of information for the UN. The increase in participation of non-governmental organizations changes how we live today. Felix Dodds states in a recent document: "In 1972 there were 39 democratic countries in the world; by 2002, there were 139." This shows that non-governmental organizations make enormous leaps within a short period of time for human rights.

Funding.

Amnesty International is financed largely by fees and donations from its worldwide membership. It says that it does not accept donations from governments or governmental organizations. According to the AI website,  "these personal and unaffiliated donations allow AI to maintain full independence from any and all governments, political ideologies, economic interests or religions. We neither seek nor accept any funds for human rights research

Criticism and controversies.

Criticism of Amnesty International includes claims of excessive pay for management, underprotection of overseas staff, associating with organizations with a dubious record on human rights protection, selection bias, ideological and foreign policy bias against either non-Western countries or Western-supported countries, or bias for terrorist groups. A recent report also shows an internal toxic work environment.  The report of Amnesty condemned that after Xi Jinping succeeded General Secretary of the Communist Party of China in 2012, human rights in China have become worse.  Amnesty International supports women's access to abortion services as basic healthcare, and the Vatican has levied criticism on Amnesty International for this.  Governments and their supporters have criticized Amnesty's criticism of their policies, including those of Australia, Czech Republic, China, Democratic Republic of the Congo, India, Iran, Israel, Qatar, Saudi Arabia, Vietnam, Russia, Nigeria and the United States, for what they assert is one-sided reporting or a failure to treat threats to security as a mitigating factor. The actions of these governments, and of other governments critical of Amnesty International, have been the subject of human rights concerns voiced by Amnesty.  The "Sudan Vision Daily", a daily newspaper in Sudan, compared Amnesty to the US National Endowment for Democracy, and claimed "it is, in essence, a British intelligence organization which is a part of the Government decision making system."

Iraq incubator incident.

In 1990, when the United States government was deciding whether or not to invade Iraq, a Kuwaiti woman, known to Congress by her first name only, Nayirah, told the congress that when Iraq invaded Kuwait, she stayed behind after some of her family left the country. She said she was volunteering in a local hospital when Iraqi soldiers stole the incubators with children in them and left them to freeze to death.

CAGE controversy.

Amnesty International suspended Gita Sahgal, its gender unit head, after she criticized Amnesty in February 2010 for its high-profile associations with Moazzam Begg, the director of Cageprisoners, representing men in extrajudicial detention.  "To be appearing on platforms with Britain's most famous supporter of the Taliban, Begg, whom we treat as a human rights defender, is a gross error of judgment," she said. Sahgal argued that by associating with Begg and Cageprisoners, Amnesty was risking its reputation on human rights. "As a former Guantanamo detainee, it was legitimate to hear his experiences, but as a supporter of the Taliban it was absolutely wrong to legitimise him as a partner," Sahgal said. She said she repeatedly brought the matter up with Amnesty for two years, to no avail. A few hours after the article was published, Sahgal was suspended from her position. Amnesty's Senior Director of Law and Policy, Widney Brown, later said Sahgal raised concerns about Begg and Cageprisoners to her personally for the first time a few days before sharing them with the "Sunday Times".  Sahgal

Pay controversy.

In February 2011, newspaper stories in the UK revealed that Irene Khan had received a payment of £533,103 from Amnesty International following her resignation from the organization on 31 December 2009, a fact pointed to from Amnesty's records for the 2009–2010 financial year. The sum paid to her was more than four times her annual salary (£132,490). The deputy secretary general, Kate Gilmore, who also resigned in December 2009, received an ex-gratia payment of £320,000. Peter Pack, the chairman of Amnesty's International Executive Committee (IEC), initially stated on 19 February 2011: "The payments to outgoing secretary general Irene Khan shown in the accounts of AI (Amnesty International) Ltd for the year ending 31 March 2010 include payments made as part of a confidential agreement between AI Ltd and Irene Khan" and that "It is a term of this agreement that no further comment on it will be made by either party."  The payment

2019 Report on workplace bullying within Amnesty International.

In February 2019, Amnesty International's management team offered to resign after an independent report found what it called a "toxic culture" of workplace bullying. Evidence of bullying, harassment, sexism and racism was uncovered after two 2018 suicides were investigated: that of 30-year Amnesty veteran Gaëtan Mootoo in Paris in May 2018 (who left a note citing work pressures); and that of 28-year-old intern Rosalind McGregor in Geneva in July 2018. An internal survey by the Konterra group with a team of psychologists was conducted in January 2019, after the 2 employees had killed themselves in 2018. The report stated that Amnesty had a toxic work culture and that workers frequently cited mental and physical health issues as a result of their work for the organization. The report found that: "39 per cent of Amnesty International staff reported that they developed mental or physical health issues as the direct result of working at Amnesty". The report concluded, "organisational culture and management

Kurdish Hunger Strike occupation.

In April 2019, 30 Kurdish activists, some of whom are on an indefinite hunger strike, occupied Amnesty International's building in London in a peaceful protest, in order to speak out against Amnesty's silence on the isolation of Abdullah Öcalan in a Turkish prison.

2019 Budgetary crisis controversy.

In May 2019 Amnesty International's Secretary General Kumi Naidoo admitted to a hole in the organization's budget of up to £17m in donor money to the end of 2020. In order to deal with the budgetary crisis Naidoo announced to staff that the organization's headquarters would have cut almost 100 jobs as a part of urgent restructuring. Unite the Union, the UK's biggest trade union, said the redundancies were a direct result of "overspending by the organisation’s senior leadership team" and have occurred "despite an increase in income". Unite, which represents Amnesty's staff, feared that cuts would fall heaviest on lower income staff. It said that in the previous year the top 23 highest earners at Amnesty International were paid a total of £2.6m– an average of £113,000 per year. Unite demanded a review of whether it is necessary to have so many managers

Awards and honours.

In 1977, Amnesty International was awarded the Nobel Peace Prize for "having contributed to securing the ground for freedom, for justice, and thereby also for peace in

Cultural impact.

Human rights concerts.

"A Conspiracy of Hope" was a short tour of six benefit concerts on behalf of Amnesty International that took place in the United States during June 1986. The purpose of the tour was not to raise funds but rather to increase awareness of human rights and of Amnesty's work on its 25th anniversary. The shows were headlined by U2, Sting and Bryan Adams and also featured Peter Gabriel, Lou Reed, Joan Baez, and The Neville Brothers. The last three shows featured a reunion of The Police. At a press conferences in each city,

Artists for Amnesty.

Amnesty International, through its "Artists for Amnesty" programme has also endorsed various cultural media

Amnesty International (also referred to as Amnesty or AI) is a non-governmental organization with its headquarters in the United Kingdom focused on human rights. The organization says it has more than eight million members and supporters around the world.

国际特赦组织(,缩写为英语:AI;又称大赦国际),是一个国际非政府组织,总部位于英国伦敦,致力于推动全球人权事业的发展,在全世界范围内拥有大约七百万成员及支持者。该组织的工作方针是对人权状况进行调研,采取相应行动,寻求终结各种侵犯人权的行为,并且为那些遭受迫害的人们伸张正义。


Origin.

Advertising executive Alex F. Osborn began developing methods for creative problem-solving in 1939. He was frustrated by employees’ inability to develop creative ideas individually for ad campaigns. In response, he began hosting group-thinking sessions and discovered a significant improvement in the quality and quantity of ideas produced by employees. He first termed the process as organized ideation and was later dubbed by participants as "brainstorm sessions", taking the concept after the use of "the brain to storm a problem." During the period when Osborn made his concept, he started writing on creative thinking, and the first notable book where he mentioned the term brainstorming is "How to Think Up" in 1942. Osborn outlined his method in the 1948 book "Your Creative Power" in chapter 33, "How to Organize a Squad to Create Ideas".  One of Osborn's key recommendations was for all the members of the brainstorming group to be provided with a clear statement of the problem to be addressed prior to the actual brainstorming session. He also explained that the guiding principle is that the problem should be simple and narrowed down to a single target. Here, brainstorming is not believed to be effective in complex problems because of a change in opinion over the desirability of restructuring such problems. While the process can address the problems in such a situation, tackling all of them may not be feasible.

Osborn's method.

Osborn claimed that two principles contribute to "ideative efficacy," these being: Following these two principles were his four general rules of brainstorming, established with intention to:

Applications.

Osborn notes that brainstorming should address a specific question; he held that sessions addressing multiple questions were inefficient.  Further, the problem must require the generation of ideas rather than judgment; he uses examples such as generating possible names for a product as proper brainstorming material, whereas analytical judgments such as whether or not to marry do not have any need for brainstorming.

Groups.

Osborn envisioned groups of around 12 participants, including both experts and novices. Participants are encouraged to provide wild and unexpected answers. Ideas receive no criticism or discussion. The group simply provide ideas that might lead to a solution and apply no analytical judgment as to the feasibility. The judgments are reserved for a later date.

Variations.

Nominal group technique.

Participants are asked to write their ideas anonymously. Then the facilitator collects the ideas and the group votes on each idea. The vote can be as simple as a show of hands in favor of a given idea. This process is called distillation.  After distillation, the top-ranked ideas may be sent back to the group or to subgroups for further brainstorming. For example, one group may work on the color required in a product. Another group may work on the size, and so forth. Each group will come back to the whole group for ranking the listed ideas. Sometimes ideas that were previously dropped may be brought forward again once the group has re-evaluated the ideas.  It is important that the facilitator is trained in this process before attempting to facilitate this technique. The group should be primed and encouraged to embrace the process. Like all team efforts, it may take a few practice sessions to train the team in the method before tackling the important ideas.

Group passing technique.

Each person in a circular group writes down one idea, and then passes the piece of paper to the next person, who adds some thoughts. This continues until everybody gets his or her original piece of paper back. By this time, it is likely that the group will have extensively elaborated on each idea.  The group may also create an "idea book" and post a distribution list or routing slip to the front of the book. On the first page is a description of the problem. The first person to receive the book lists his or her ideas and then routes the book to the next person on the distribution list. The second person can log new ideas or add to the ideas of the previous person. This continues until the distribution list is exhausted. A follow-up "read out" meeting is then held to discuss the ideas logged in the book. This technique takes longer, but it allows individuals time to think deeply about the problem.

Team idea mapping method.

This method of brainstorming works by the method of association. It may improve collaboration and increase the quantity of ideas, and is designed so that all attendees participate and no ideas are rejected.  The process begins with a well-defined topic. Each participant brainstorms individually, then all the ideas are merged onto one large idea map. During this consolidation phase, participants may discover a common understanding of the issues as they share the meanings behind their ideas. During this sharing, new ideas may arise by the association, and they are added to the map as well. Once all the ideas are captured, the group can prioritize and/or take action.

Directed brainstorming.

Directed brainstorming is a variation of electronic brainstorming (described below). It can be done manually or with computers. Directed brainstorming works when the solution space (that is, the set of criteria for evaluating a good idea) is known prior to the session. If known, those criteria can be used to constrain the ideation process intentionally.  In directed brainstorming, each participant is given one sheet of paper (or electronic form) and told the brainstorming question. They are asked to produce one response and stop, then all of the papers (or forms) are randomly swapped among the participants. The participants are asked to look at the idea they received and to create a new idea that improves on that idea based on the initial criteria. The forms are then swapped again and respondents are asked to improve upon the ideas, and the process is repeated for three or more rounds.  In the laboratory, directed brainstorming has been found to almost triple the productivity of groups over electronic brainstorming.

Guided brainstorming.

A guided brainstorming session is time set aside to brainstorm either individually or as a collective group about a particular subject under the constraints of perspective and time. This type of brainstorming removes all cause for conflict and constrains conversations while stimulating critical and creative thinking in an engaging, balanced environment.  Participants are asked to adopt different mindsets for pre-defined period of time while contributing their ideas to a central mind map drawn by a pre-appointed scribe. Having examined a multi-perspective point of view, participants seemingly see the simple solutions that collectively create greater growth. Action is assigned individually.  Following a guided brainstorming session participants emerge with ideas ranked for further brainstorming, research and questions remaining unanswered and a prioritized, assigned, actionable list that leaves everyone with a clear understanding of what needs to happen next and the ability to visualize the combined future focus and greater goals of the group nicely.

Individual brainstorming.

"Individual brainstorming" is the use of brainstorming in solitary situations. It typically includes such techniques as free writing, free speaking, word association, and drawing a mind map, which is a visual note taking technique in which people diagram their thoughts. Individual brainstorming is a useful method in creative writing and has been shown to be superior to traditional group brainstorming.

Question brainstorming.

This process involves brainstorming the "questions", rather than trying to come up with immediate answers and short term solutions. Theoretically, this technique should not inhibit participation as there is no need to provide solutions. The answers to the questions form the framework for constructing future action plans. Once the list of questions is set, it may be necessary to prioritize them to reach to the best solution in an orderly way.  "Questorming" is another term for this mode of inquiry.

Methods to improving brainstorming sessions.

There are a number of ways that groups can improve the effectiveness and quality of their brainstorming sessions.

Alternatives to brainstorming.

If brainstorming does not work for your group, there are some alternatives that you could use instead.

Electronic brainstorming (EBS).

Although the brainstorming can take place online through commonly available technologies such as email or interactive web sites, there have also been many efforts to develop customized computer software that can either replace or enhance one or more manual elements of the brainstorming process.  Early efforts, such as GroupSystems at University of Arizona or Software Aided Meeting Management (SAMM) system at the University of Minnesota, took advantage of then-new computer networking technology, which was installed in rooms dedicated to computer supported meetings. When using these electronic meeting systems (EMS, as they came to be called), group members simultaneously and independently entered ideas into a computer terminal. The software collected (or "pools") the ideas into a list, which could be displayed on a central projection screen (anonymized if desired). Other elements of these EMSs could support additional activities such as categorization of ideas, elimination of duplicates, assessment and discussion of prioritized or controversial ideas. Later EMSs capitalized on advances in computer networking and internet protocols to support asynchronous brainstorming sessions over extended periods of time and in multiple locations.  Introduced along with the EMS by Nunamaker and colleagues at University of Arizona was electronic brainstorming (EBS). By utilizing customized computer software for groups ("group decision support systems" or "groupware"), EBS can replace face-to-face brainstorming. An example of groupware is the "GroupSystems," a software developed by University of Arizona. After an idea discussion has been posted on "GroupSystems", it is displayed on each group member's computer. As group members simultaneously type their comments on separate computers, those comments are anonymously pooled and made available to all group members for evaluation and further elaboration.  Compared to face-to-face brainstorming, not only does EBS enhanced efficiency by eliminating travelling and turn-taking during group discussions, it also excluded several psychological constraints associated with face-to-face meetings. Identified by Gallupe and colleagues, both production blocking (reduced idea generation due to turn-taking and forgetting ideas in face-to-face brainstorming) and evaluation apprehension (a general concern experienced by individuals for how others in the presence are evaluating them) are reduced in EBS. These positive psychological effects increase with group size. A perceived advantage of EBS is that all ideas can be archived electronically in their original form, and then retrieved later for further thought and discussion. EBS also enables much larger groups to brainstorm on a topic than would normally be productive in a traditional brainstorming session.  Computer supported brainstorming may overcome some of the challenges faced by traditional brainstorming methods. For example, ideas might be "pooled" automatically, so that individuals do not need to wait to take a turn, as in verbal brainstorming. Some software programs show all ideas as they are generated (via chat room or e-mail). The display of ideas may cognitively stimulate brainstormers, as their attention is kept on the flow of ideas being generated without the potential distraction of social cues such as facial expressions and verbal language. EBS techniques have been shown to produce more ideas and help individuals focus their attention on the ideas of others better than a brainwriting technique (participants write individual written notes in silence and then subsequently communicate them with the group). The production of more ideas has been linked to the fact that paying attention to others' ideas leads to non-redundancy, as brainstormers try to avoid to replicate or repeat another participant's comment or idea. Conversely, the production gain associated with EBS was less found in situations where EBS group members focused too much on generating ideas that they ignored ideas expressed by others. The production gain associated with "GroupSystem" users' attentiveness to ideas expressed by others has been documented by Dugosh and colleagues. EBS group members who were instructed to attend to ideas generated by others outperformed those who were not in terms of creativity.  According to a meta-analysis comparing EBS to face-to-face brainstorming conducted by DeRosa and colleagues, EBS has been found to enhance both the production of non-redundant ideas and the quality of ideas produced. Despite the advantages demonstrated by EBS groups, EBS group members reported less satisfaction with the brainstorming process compared to face-to-face brainstorming group members.  Some web-based brainstorming techniques allow contributors to post their comments anonymously through the use of avatars. This technique also allows users to log on over an extended time period, typically one or two weeks, to allow participants some "soak time" before posting their ideas and feedback. This technique has been used particularly in the field of new product development, but can be applied in any number of areas requiring collection and evaluation of ideas.  Some limitations of EBS include the fact that it can flood people with too many ideas at one time that they have to attend to, and people may also compare their performance to others by analyzing how many ideas each individual produces (social matching).

Incentives.

Some research indicates that incentives can augment creative processes. Participants were divided into three conditions. In Condition I, a flat fee was paid to all participants. In the Condition II, participants were awarded points for every unique idea of their own, and subjects were paid for the points that they earned. In Condition III, subjects were paid based on the impact that their idea had on the group; this was measured by counting the number of group ideas derived from the specific subject's ideas. Condition III outperformed Condition II, and Condition II outperformed Condition I at a statistically significant level for most measures. The results demonstrated that participants were willing to work far longer to achieve unique results in the expectation of compensation.

Challenges to effective group brainstorming.

A good deal of research refutes Osborn's claim that group brainstorming could generate more ideas than individuals working alone. For example, in a review of 22 studies of group brainstorming, Michael Diehl and Wolfgang Stroebe found that, overwhelmingly, groups brainstorming together produce fewer ideas than individuals working separately. However, this conclusion is brought into question by a subsequent review of 50 studies by Scott G. Isaksen showed that a misunderstanding of the tool, and weak application of the methods (including lack of facilitation), and the artificiality of the problems and groups undermined most such studies, and the validity of their conclusions.  Several factors can contribute to a loss of effectiveness in group brainstorming.  Blocking:  Because only one participant may give an idea at any one time, other participants might forget the idea they were going to contribute or not share it because they see it as no longer important or relevant. Further, if we view brainstorming as a cognitive process in which "a participant generates ideas (generation process) and stores them in short-term memory (memorization process) and then eventually extracts some of them from its short-term memory to express them (output process)", then blocking is an even more critical challenge because it may also inhibit a person's train of thought in generating their own ideas and remembering them. Collaborative fixation: Exchanging ideas in a group may reduce the number of domains that a group explores for additional ideas. Members may also conform their ideas to those of other members, decreasing the novelty or variety of ideas, even though the overall number of ideas might not decrease.  Evaluation apprehension: Evaluation apprehension was determined to occur only in instances of personal evaluation. If the assumption of collective assessment were in place, real-time judgment of ideas, ostensibly an induction of evaluation apprehension, failed to induce significant variance.  Free-writing: Individuals may feel that their ideas are less valuable when combined with the ideas of the group at large. Indeed, Diehl and Stroebe demonstrated that even when individuals worked alone, they produced fewer ideas if told that their output would be judged in a group with others than if told that their output would be judged individually. However, experimentation revealed free-writing as only a marginal contributor to productivity loss, and type of session (i.e., real vs. nominal group) contributed much more.  Personality characteristics: Extroverts have been shown to outperform introverts in computer mediated groups. Extroverts also generated more unique and diverse ideas than introverts when additional methods were used to stimulate idea generation, such as completing a small related task before brainstorming, or being given a list of the classic rules of brainstorming.  Social matching: One phenomenon of group brainstorming is that participants will tend to alter their rate of productivity to match others in the group. This can lead to participants generating fewer ideas in a group setting than they would individually because they will decrease their own contributions if they perceive themselves to be more productive than the group average. On the other hand, the same phenomenon can also increase an individual's rate of production to meet the group average.

Brainstorming is a group creativity technique by which efforts are made to find a conclusion for a specific problem by gathering a list of ideas spontaneously contributed by its members.

脑力激荡法(英语:Brainstorming),又称为-{zh-cn:脑力激荡法;zh-tw:头脑风暴法;}-,是一种为激发创造力、强化思考力而设计出来的一种方法。此法是美国BBDO(英语:Batten, Bcroton, Durstine and Osborn)广告公司创始人亚历克斯‧奥斯本于1938年首创的。