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Topic Review
Pine Ridge Indian Reservation
The Pine Ridge Indian Reservation (Template:Lang-lkt), also called Pine Ridge Agency, is an Oglala Lakota Native American reservation located in the U.S. state of South Dakota. Originally included within the territory of the Great Sioux Reservation, Pine Ridge was created by the Act of March 2, 1889, 25 Stat. 888. in the southwest corner of South Dakota on the Nebraska border. Today it consists of 3,468.85 sq mi (8,984.3 km2) of land area and is the eighth-largest reservation in the United States, larger than Delaware and Rhode Island combined. The reservation encompasses the entirety of Oglala Lakota County and Bennett County, the southern half of Jackson County, and a small section of Sheridan County added by Executive Order No. 2980 of February 20, 1904. Of the 3,142 counties in the United States, these are among the poorest. Only 84,000 acres (340 km2) of land are suitable for agriculture. The 2000 census population of the reservation was 15,521; but a study conducted by Colorado State University and accepted by the United States Department of Housing and Urban Development has estimated the resident population to reach 28,787. Pine Ridge is the site of several events that mark milestones in the history between the Sioux of the area and the United States (U.S.) government. Stronghold Table—a mesa in what is today the Oglala-administered portion of Badlands National Park—was the location of the last of the Ghost Dances. The U.S. authorities' attempt to repress this movement eventually led to the Wounded Knee Massacre on December 29, 1890. A mixed band of Miniconjou Lakota and Hunkpapa Sioux, led by Chief Spotted Elk, sought sanctuary at Pine Ridge after fleeing the Standing Rock Agency, where Sitting Bull had been killed during efforts to arrest him. The families were intercepted by a heavily armed detachment of the Seventh Cavalry, which attacked them, killing many women and children as well as warriors. This was the last large engagement between U.S. forces and Native Americans and marked the end of the western frontier. Changes accumulated in the last quarter of the 20th century; in 1971 the Oglala Sioux Tribe (OST) started Oglala Lakota College, a tribal college, which offers 4-year degrees. In 1973 decades of discontent at the Pine Ridge Reservation resulted in a grassroots protest that escalated into the Wounded Knee Incident, gaining national attention. Members of the Oglala Lakota, the American Indian Movement and supporters occupied the town in defiance of federal and state law enforcement in a protest that turned into an armed standoff lasting 71 days. This event inspired American Indians across the country and gradually led to changes at the reservation, with a revival of some cultural traditions. In 1981 the Lakota Tim Giago started the Lakota Times at Pine Ridge, the first independent Native American newspaper in the nation; he published it until selling it in 1998. Located at the southern end of the Badlands, the reservation is part of the mixed grass prairie, an ecological transition zone between the short-grass and tall-grass prairies; all are part of the Great Plains. A great variety of plant and animal life flourishes on and adjacent to the reservation, including the endangered black-footed ferret. The area is also important in the field of paleontology; it contains deposits of Pierre Shale formed on the seafloor of the Western Interior Seaway, evidence of the marine Cretaceous–Paleogene boundary, and one of the largest deposits of fossils of extinct mammals from the Oligocene epoch.
  • 6.2K
  • 07 Oct 2022
Topic Review
Pole Weapon
A pole weapon or pole arm is a close combat weapon in which the main fighting part of the weapon is fitted to the end of a long shaft, typically of wood, thereby extending the user's effective range and striking power. Pole weapons are predominantly melee weapons, with a subclass of spear-like designs fit for both thrusting and throwing. Because many pole weapons were adapted from agricultural implements or other fairly abundant tools, and contained relatively little metal, they were cheap to make and readily available. When warfare would break out and the belligerents had a poorer class who could not pay for dedicated military weapons, leaders would often appropriate tools as cheap weapons. The cost of training was comparatively minimal, since these conscripted farmers had spent most of their lives using these "weapons" in the fields. This made polearms the favored weapon of peasant levies and peasant rebellions the world over. Pole arms can be divided into three broad categories: those designed for extended reach and thrusting tactics used in pike square or phalanx combat; those designed to increase leverage (thanks to hands moving freely on a pole) to maximize centrifugal force against cavalry; and those designed for throwing tactics used in skirmish line combat. Because their versatility, high effectiveness and cheap cost, polearms experimentation led to many variants and were the most frequently used weapons on the battlefield: bills, picks, dane axes, spears, glaives, guandaos, pudaos, poleaxes, halberds, harpoons, sovnyas, tridents, naginatas, bardiches, war scythes, and lances are all varieties of pole arms. Pole arms were common weapons on post-classical battlefields of Asia and Europe. Their range and impact force made them effective weapons against armored warriors on horseback, because they could be dismounted and/or penetrate said armor. The Renaissance saw a plethora of varieties. Pole arms in modern times are largely constrained to ceremonial military units such as the Papal Swiss Guard or Yeomen of the Guard, or traditional martial arts. Chinese martial arts in particular have preserved a wide variety of weapons and techniques.
  • 6.2K
  • 09 Nov 2022
Topic Review
Abnormality (Behavior)
Abnormality (or dysfunctional behavior) is a behavioral characteristic assigned to those with conditions that are regarded as rare or dysfunctional. Behavior is considered to be abnormal when it is atypical or out of the ordinary, consists of undesirable behavior, and results in impairment in the individual's functioning. Abnormality in behavior, is that in which is considered deviant from specific societal, cultural and ethical expectations. These expectations are broadly dependent on age, gender, traditional and societal categorizations. The definition of abnormal behavior is an often debated issue in abnormal psychology, because of these subjective variables. Abnormal behavior should not be confused with unusual behavior. Behavior that is out of the ordinary is not necessarily indicative of a mental or psychological disorder. Abnormal behavior, on the other hand, while not a mental disorder in itself, is often an indicator of a possible mental and/or psychological disorder. A psychological disorder is defined as an "ongoing dysfunctional pattern of thought, emotion, and behavior that causes significant distress, and is considered deviant in that person's culture or society". It is important to note that abnormal behavior, as it relates to psychological disorders, would be "ongoing" and a cause of "significant distress". A mental disorder describes a patient who has a medical condition whereby the medical practitioner makes a judgement that the patient is exhibiting abnormal behavior based on the DSM-5 criteria. Thus, simply because a behavior is unusual it does not make it abnormal; it is only considered abnormal if it meets these criteria. The Diagnostic and Statistical Manual of Mental Disorders, or DSM-5, is used by both researchers and clinicians in diagnosing a potential mental disorder. The criteria needed to be met in the DSM-5 varies for each mental disorder. Unlike physical abnormalities in ones health whose symptoms are objective, psychology health professionals cannot use objective symptoms when evaluating someone for abnormalities in behavior.
  • 6.2K
  • 03 Nov 2022
Topic Review
Iridology
Iridology (also known as iridodiagnosis or iridiagnosis) is an alternative medicine technique whose proponents claim that patterns, colors, and other characteristics of the iris can be examined to determine information about a patient's systemic health. Practitioners match their observations to iris charts, which divide the iris into zones that correspond to specific parts of the human body. Iridologists see the eyes as "windows" into the body's state of health. Iridologists claim they can use the charts to distinguish between healthy systems and organs in the body and those that are overactive, inflamed, or distressed. Iridologists claim this information demonstrates a patient's susceptibility towards certain illnesses, reflects past medical problems, or predicts later health problems. As opposed to evidence-based medicine, iridology is not supported by quality research studies and is widely considered pseudoscience. The features of the iris are one of the most stable features on the human body throughout life. The stability of iris structures is the foundation of the biometric technology which uses iris recognition for identification purposes. In 1979, Bernard Jensen, a leading American iridologist, and two other iridology proponents failed to establish the basis of their practice when they examined photographs of the eyes of 143 patients in an attempt to determine which ones had kidney impairments. Of the patients, forty-eight had been diagnosed with kidney disease, and the rest had normal kidney function. Based on their analysis of the patients' irises, the three iridologists could not detect which patients had kidney disease and which did not.
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  • 04 Nov 2022
Topic Review
Instability of Peptide and Possible Causes of Degradation
Peptides are different from proteins. Although both are composed of amino acids, peptides are smaller molecules comprised of two or more amino acids linked by peptide bonds, while proteins are long chains of amino acids that may have a much larger number of amino acids. Peptide stability in aqueous solutions is critical when developing parenteral formulations, as the potency of a peptide is often compromised due to chemical or physical degradation pathways.
  • 6.2K
  • 29 Mar 2023
Topic Review
Blended Learning
Blended learning is an approach to education that combines online educational materials and opportunities for interaction online with traditional place-based classroom methods. It requires the physical presence of both teacher and student, with some elements of student control over time, place, path, or pace. While students still attend "brick-and-mortar" schools with a teacher present, face-to-face classroom practices are combined with computer-mediated activities regarding content and delivery. Blended learning is also used in professional development and training settings. Since blended learning is highly context-dependent, a universal conception of it is difficult. Some reports have claimed that a lack of consensus on a hard definition of blended learning has led to difficulties in research on its effectiveness. A well-cited 2013 study broadly defined blended learning as a mixture of online and in-person delivery where the online portion effectively replaces some of the face-to-face contact time rather than supplementing it. Additionally, a 2015 meta-analysis that historically looked back at a comprehensive review of evidence-based research studies around blended learning, found commonalities in defining that blended learning was "considered a combination of traditional f2f [face to face] modes of instruction with online modes of learning, drawing on technology-mediated instruction, where all participants in the learning process are separated by distance some of the time." This report also found that all of these evidence-based studies concluded that student achievement was higher in blended learning experiences when compared to either fully online or fully face-to-face learning experiences. "Blended learning" is sometimes used in the same breath as "personalized learning" and differentiated instruction.
  • 6.2K
  • 17 Oct 2022
Topic Review
Single-Letter Second-Level Domain
Single-letter second-level domains are domain names in which the second-level domain consists of only one letter, such as x.com. In 1993, the Internet Assigned Numbers Authority (IANA) explicitly reserved all single-letter and single-digit second-level domain names in the top-level domains com, net, and org, and grandfathered those that had already been assigned. In December 2005, ICANN considered auctioning these domains.
  • 6.2K
  • 03 Nov 2022
Topic Review
Rock–Paper–Scissors
Rock–paper–scissors (also known as paper-scissors-rock or other variants) is a hand game usually played between two people, in which each player simultaneously forms one of three shapes with an outstretched hand. These shapes are "rock" (a closed fist), "paper" (a flat hand), and "scissors" (a fist with the index finger and middle finger extended, forming a V). "Scissors" is identical to the two-fingered V sign (also indicating "victory" or "peace") except that it is pointed horizontally instead of being held upright in the air. A simultaneous, zero-sum game, it has only two possible outcomes: a draw, or a win for one player and a loss for the other. A player who decides to play rock will beat another player who has chosen scissors ("rock crushes scissors" or sometimes "blunts scissors"), but will lose to one who has played paper ("paper covers rock"); a play of paper will lose to a play of scissors ("scissors cuts paper"). If both players choose the same shape, the game is tied and is usually immediately replayed to break the tie. The type of game originated in China and spread with increased contact with East Asia, while developing different variants in signs over time. Other names for the game in the English-speaking world include roshambo and other orderings of the three items, with "rock" sometimes being called "stone". Rock–paper–scissors is often used as a fair choosing method between two people, similar to coin flipping, drawing straws, or throwing dice in order to settle a dispute or make an unbiased group decision. Unlike truly random selection methods, however, rock–paper–scissors can be played with a degree of skill by recognizing and exploiting non-random behavior in opponents.
  • 6.2K
  • 25 Oct 2022
Topic Review
Broken/Angular Diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the visual angle, and in optics, it is the angular aperture (of a lens). The angular diameter can alternatively be thought of as the angle through which an eye or camera must rotate to look from one side of an apparent circle to the opposite side. Angular radius equals half of the angular diameter.
  • 6.2K
  • 04 Nov 2022
Topic Review
May 20: Vasco da Gama Reaches India
Vasco da Gama’s arrival in Calicut, India on May 20, 1498, marked the first time a European reached India by sea, successfully navigating around the Cape of Good Hope and across the Indian Ocean. This event opened a direct maritime trade route between Europe and Asia, breaking the centuries-old overland monopoly held by Middle Eastern and Venetian traders. It initiated an era of European exploration, imperial expansion, and global maritime dominance, especially for Portugal.
  • 6.2K
  • 20 May 2025
Topic Review
48,XXXY Syndrome
48,XXXY syndrome is a chromosomal condition in boys and men that causes intellectual disability, developmental delays, physical differences, and an inability to father biological children (infertility). Its signs and symptoms vary among affected individuals.
  • 6.2K
  • 23 Dec 2020
Topic Review Peer Reviewed
Lichen as Multipartner Symbiotic Relationships
Lichens have long been considered as composite organisms composed of algae and/or cyanobacteria hosted by a fungus in a mutualistic relationship. Other organisms have been gradually discovered within the lichen thalli, such as multiple algal species, yeasts, or even viruses. Of pivotal relevance is the existence of the lichen microbiome, which is a community of microorganisms that can be found living together on the lichen surface. This community performs a growing number of functions. In this entry, we explore the journey of lichens being considered from a dual partnership to a multi-species symbiotic relationship. 
  • 6.2K
  • 04 Aug 2022
Topic Review
Mercator 1569 World Map
The Mercator world map of 1569 is titled Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata (Renaissance Latin for "New and more complete representation of the terrestrial globe properly adapted for use in navigation"). The title shows that Gerardus Mercator aimed to present contemporary knowledge of the geography of the world and at the same time 'correct' the chart to be more useful to sailors. This 'correction', whereby constant bearing sailing courses on the sphere (rhumb lines) are mapped to straight lines on the plane map, characterizes the Mercator projection. While the map's geography has been superseded by modern knowledge, its projection proved to be one of the most significant advances in the history of cartography, inspiring map historian Nordenskiöld to write "The master of Rupelmonde stands unsurpassed in the history of cartography since the time of Ptolemy." The projection heralded a new era in the evolution of navigation maps and charts and it is still their basis. The map is inscribed with a great deal of text. The framed map legends (or cartouches) cover a wide variety of topics: a dedication to his patron and a copyright statement; discussions of rhumb lines, great circles and distances; comments on some of the major rivers; accounts of fictitious geography of the north pole and the southern continent. The full Latin texts and English translations of all the legends are given below. Other minor texts are sprinkled about the map. They cover such topics as the magnetic poles, the prime meridian, navigational features, minor geographical details, the voyages of discovery and myths of giants and cannibals. These minor texts are also given below. A comparison with world maps before 1569 shows how closely Mercator drew on the work of other cartographers and his own previous works, but he declares (Legend 3) that he was also greatly indebted to many new charts prepared by Portuguese and Spanish sailors in the portolan tradition. Earlier cartographers of world maps had largely ignored the more accurate practical charts of sailors, and vice versa, but the age of discovery, from the closing decade of the fifteenth century, stimulated the integration of these two mapping traditions: Mercator's world map is one of the earliest fruits of this merger.
  • 6.2K
  • 22 Nov 2022
Topic Review
Void
Cosmic voids are vast spaces between filaments (the largest-scale structures in the universe), which contain very few or no galaxies. The cosmological evolution of the void regions differs drastically from the evolution of the Universe as a whole: there is a long stage when the curvature term dominates, which prevents the formation of galaxy clusters and massive galaxies. Hence, although even the emptiest regions of voids contain more than ~15% of the average matter density of the Universe, the voids look almost empty for an observer. Voids typically have a diameter of 10 to 100 megaparsecs (30 to 300 million light years); particularly large voids, defined by the absence of rich superclusters, are sometimes called supervoids. They were first discovered in 1978 in a pioneering study by Stephen Gregory and Laird A. Thompson at the Kitt Peak National Observatory. Voids are believed to have been formed by baryon acoustic oscillations in the Big Bang, collapses of mass followed by implosions of the compressed baryonic matter. Starting from initially small anisotropies from quantum fluctuations in the early universe, the anisotropies grew larger in scale over time. Regions of higher density collapsed more rapidly under gravity, eventually resulting in the large-scale, foam-like structure or "cosmic web" of voids and galaxy filaments seen today. Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe. Voids appear to correlate with the observed temperature of the cosmic microwave background (CMB) because of the Sachs–Wolfe effect. Colder regions correlate with voids and hotter regions correlate with filaments because of gravitational redshifting. As the Sachs–Wolfe effect is only significant if the universe is dominated by radiation or dark energy, the existence of voids is significant in providing physical evidence for dark energy.
  • 6.2K
  • 18 Oct 2022
Topic Review
Neuroscience of Flow States
Flow states have been shown to help people reach peak performance, yet this elusive state is not easily attained. This entry describes the current state of literature on flow by addressing the environmental influences as well as the cognitive and neurocognitive elements that underlie the experience. In particular, the research focuses on the transition of cognitive control from an explicit to an implicit process. This is further expanded upon to look at the current, yet related neurocognitive research of high performance associated with the implicit process of automaticity. Finally, this entry focuses on transcranial direct current stimulation (tDCS) as a novel method to facilitate the induction of flow states. 
  • 6.2K
  • 26 Oct 2020
Topic Review
Communication
Communication (from Latin communicare, meaning "to share"or "to be in relation with") is "an apparent answer to the painful divisions between self and other, private and public, and inner thought and outer word." As this definition indicates, communication is difficult to define in a consistent manner, because it is commonly used to refer to a wide range of different behaviors (broadly: "the transfer of information"), or to limit what can be included in the category of communication (for example, requiring a "conscious intent" to persuade). John Peters argues the difficulty of defining communication emerges from the fact that communication is both a universal phenomena (because everyone communicates), and a specific discipline of institutional academic study. One possible definition of communication is the act of developing meaning among entities or groups through the use of sufficiently mutually understood signs, symbols, and semiotic conventions. In Claude Shannon's and Warren Weaver's influential model, human communication was imagined to function like a telephone or telegraph. Accordingly, they conceptualized communication as involving discrete steps: These elements are now understood to be substantially overlapping and recursive activities rather than steps in a sequence. For example, communicative actions can commence before a communicator formulates a conscious attempt to do so, as in the case of phatics; likewise, communicators modify their intentions and formulations of a message in response to real-time feedback (e.g., a change in facial expression). Practices of decoding and interpretation are culturally enacted, not just by individuals (genre conventions, for instance, trigger anticipatory expectations for how a message is to be received), and receivers of any message operationalize their own frames of reference in interpretation. The scientific study of communication can be divided into: The channel of communication can be visual, auditory, tactile/haptic (e.g. Braille or other physical means), olfactory, electromagnetic, or biochemical. Human communication is unique for its extensive use of abstract language. Development of civilization has been closely linked with progress in telecommunication.
  • 6.2K
  • 02 Nov 2022
Topic Review
Context Collapse
Context collapse refers to the phenomenon in digital communication where distinct social spheres or contexts intersect, leading to challenges in managing audience expectations, privacy boundaries, and self-presentation. It occurs when content intended for one audience becomes visible to multiple, potentially disparate audiences, blurring the boundaries between personal, professional, and social identities online. Context collapse often raises concerns about privacy, authenticity, and social repercussions in digital environments.
  • 6.2K
  • 08 Feb 2024
Topic Review
Cocoa By-Products
Theobroma cacao L., the cocoa-producing tree, belongs to the order of Malvales, family Malvaceae and genus Theobroma. Its name has Greek origins, Theos and Bromos, meaning “food of the gods”.
  • 6.2K
  • 19 Apr 2022
Topic Review
Islamist Shi'ism
Islamist Shi'ism (Persian: تشیع اخوانی‎) is a denomination of Twelver Shia Islam greatly inspired by the Sunni Muslim Brotherhood ideologies and politicized version of Ibn Arabi's mysticism. It sees Islam as a political system and differs from the other mainstream Usuli and Akhbari groups in favoring the idea of formation of Islamist state in occultation of the twelfth Imam. Hadi Khosroshahi was the first person to identify himself as ikhwani (Islamist) Shia. Because of the concept of the hidden Imam, Muhammad al-Mahdi, Shia Islam is inherently secular in the age of occultation, so islamist Shi'ites had to borrow ideas from Sunni islamists and adjust them with Shi'i outlook. Islamism (Persian: اخوانی گری‎) (also often called political Islam or Islamic fundamentalism) is a political ideology which posits that modern states and regions should be reconstituted in constitutional, economic and judicial terms, in accordance with what is conceived as a revival or a return to authentic Islamic practice in its totality. Ideologies dubbed Islamist may advocate a "revolutionary" strategy of Islamizing society through exercise of state power, or alternately a "reformist" strategy to re-Islamizing society through grassroots social and political activism. Islamists may emphasize the implementation of sharia, pan-Islamic political unity, the creation of Islamic states, or the outright removal of non-Muslim influences; particularly of Western or universal economic, military, political, social, or cultural nature in the Muslim world; that they believe to be incompatible with Islam and a form of Western neocolonialism. Some analysts such as Graham E. Fuller describe it as a form of identity politics, involving "support for (Muslim) identity, authenticity, broader regionalism, revivalism, (and) revitalization of the community." The term itself is not popular among many Islamists who believe it inherently implies violent tactics, human rights violations, and political extremism when used by Western mass media. Some authors prefer the term "Islamic activism", while Islamist political figures such as Rached Ghannouchi use the term "Islamic movement" rather than Islamism. Central and prominent figures in 20th-century Islamism include Sayyid Rashid Rida, Hassan al-Banna, Sayyid Qutb, Abul A'la Maududi, Hasan al-Turabi,and Ruhollah Khomeini.
  • 6.2K
  • 20 Oct 2022
Topic Review
Islamic Primary Schools in the Netherlands
Because of the constitutional Freedom of education in the Netherlands, everyone can establish a school and is entitled to full state funding. There now are 52 primary Islamic schools, with around 12,500 pupils mostly of Turkish and Moroccan descent. They focus on developing an Islamic religious identity, and high educational quality and pupil achievement. Because most pupils come from socioeconomic disadvantaged backgrounds, the schools receive nearly twice as much budget than schools with a predominantly non-disadvantaged population. The existence of Islamic schools has always been controversial. Their output in terms of academic achievement is relatively high, however. In an absolute sense they achieve below the “average” Dutch school, but when compared with schools with the same disadvantaged pupil population, they achieve better. Lately, there have been problems with secondary Islamic schools in the Netherlands. As a result, several politicians propose to abolish the Freedom of education act.  
  • 6.2K
  • 03 Nov 2020
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