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Topic Review
Global South
The Global South is a term often used to identify lower-income countries on one side of the so-called global North–South divide, the other side being the countries of the Global North. As such the term does not inherently refer to a geographical south; for example, most of the Global South is actually within the Northern Hemisphere. The term, as used by governmental and development organizations, was first introduced as a more open and value free alternative to "Third World" and similar potentially "valuing" terms like developing countries. Countries of the Global South have been described as newly industrialized or in the process of industrializing and frequently have a history of colonialism by Northern, often European, states. The countries of Brazil, China, India, Indonesia, and Mexico have the largest populations and economies among Southern states. The overwhelming majority of these countries are located in or near the tropics.
  • 12.2K
  • 14 Oct 2022
Topic Review
Pi-Stacking
In chemistry, pi stacking (also called π–π stacking) refers to the presumptive attractive, noncovalent interactions (orbital overlap) between the pi bonds of aromatic rings. However this is a misleading description of the phenomena since direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive. What is more commonly observed (see figure to the right) is either a staggered stacking (parallel displaced) or pi-teeing (perpendicular T-shaped) interaction both of which are electrostatic attractive For example, the most commonly observed interactions between aromatic rings of amino acid residues in proteins is a stagered stacked followed by a perpendular orientation. Sandwiched orientations are relatively rare. Pi stacking is repulsive as it places carbon atoms with partial negative charges from one ring on top of other partial negatively charged carbon atoms from the second ring and hydrogen atoms with partial postive charges on top of other hydrogen atoms that likewise carry partial positive charges. In staggered stacking, one of the two aromatic rings is offset sideways so that the carbon atoms with partial negative charge in the first ring are placed above hydrogen atoms with partial positive charge in the second ring so that the electrostatic interactions become attractive. Likewise, pi-teeing interactions in which the two rings are oriented perpendicultar to either other is electrostatically attractive as it places partial postively charged hydrogen atoms in close proximity to partially negatively charged carbon atoms. An alternative explanation for the preference for staggered stacking is due to the balance between van der Waals interactions (attractive dispersion plus Pauli repulsion). These staggered stacking and π-teeing interactions between aromatic rings are important in nucleobase stacking within DNA and RNA molecules, protein folding, template-directed synthesis, materials science, and molecular recognition. Despite the wide use of term pi stacking in the scientific literature, there is no theoretical justification for its use.
  • 12.2K
  • 12 Oct 2022
Topic Review
2004 Indian Ocean Tsunami in Malaysia
The tsunami is one of the deadliest natural disasters, responsible for more than 260,000 deaths and billions in economic losses over the last two decades. The footage of the devastating power of the 2004 Indian Ocean tsunami perhaps remains vivid in the memory of most survivors, and Malaysia was one of the countries affected by the unprecedented 2004 tsunami. It was the first time the Malaysian government had managed such a great disaster. A compilation of post-event observations regarding tsunami characteristics is first presented in the form of maps, followed by building damage, including damage modes of wall failure, total collapse, debris impact and tilting of structures.
  • 12.2K
  • 25 Aug 2022
Topic Review
Pharmakon
Pharmakon, in philosophy and critical theory, is a composite of three meanings: remedy, poison, and scapegoat. The first and second senses refer to the everyday meaning of pharmacology (and to its sub-field, toxicology), deriving from the Greek source term φάρμακον (phármakon), denoting any drug, while the third sense refers to the pharmakos ritual of human sacrifice. A further sub-sense of pharmakon as remedy which is of interest to some current authors is given by the Liddell-Scott-Jones Greek–English Lexicon as "a means of producing something". In recent philosophical work, the term centers on Jacques Derrida's "Plato's Pharmacy", and the notion that writing is a pharmakon. Whereas a straightforward view on Plato's treatment of writing (in Phaedrus) suggests that writing is to be rejected as strictly poisonous to the ability to think for oneself in dialogue with others (i.e. to anamnesis), Bernard Stiegler argues that "the hypomnesic appears as that which constitutes the condition of the anamnesic"—in other words, externalised time-bound communication is necessary for original creative thought, in part because it is the primordial support of culture. Michael Rinella has written a book-length review of the pharmakon within a historical context, with an emphasis on the relationship between pharmakoi in the standard drug sense and the philosophical understanding of the term. Adrian Mróz, a Polish-American philosopher and musician, analyses its application to art and argues that pharmakon is any physical, mental, or behavioral object which can cut (techne). In other words, pharmaka are agential and responsible for changes in consciousness.
  • 12.1K
  • 07 Nov 2022
Topic Review
Decay Theory
The Decay theory is a theory that proposes that memory fades due to the mere passage of time. Information is therefore less available for later retrieval as time passes and memory, as well as memory strength, wears away. When an individual learns something new, a neurochemical "memory trace" is created. However, over time this trace slowly disintegrates. Actively rehearsing information is believed to be a major factor counteracting this temporal decline. It is widely believed that neurons die off gradually as we age, yet some older memories can be stronger than most recent memories. Thus, decay theory mostly affects the short-term memory system, meaning that older memories (in long-term memory) are often more resistant to shocks or physical attacks on the brain. It is also thought that the passage of time alone cannot cause forgetting, and that decay theory must also take into account some processes that occur as more time passes.
  • 12.1K
  • 31 Oct 2022
Topic Review
BMW 5 Series (E34)
The BMW E34 is the third generation of the BMW 5 Series, which was produced from 1987 until 1996. Initially launched as a sedan in January 1988, the E34 also saw a "Touring" wagon (estate) bodystyle in September 1992, a first for the 5 Series. BMW replaced the E34 with the E39 5 Series in December 1995, although E34 Touring models remained in production until June 1996. The E34 generation marked the first time all-wheel drive was incorporated into the 5 Series with the 525iX, and the first V8 engine to be used in a 5 Series. The E34 also saw the introduction of stability control (ASC), traction control (ASC+T) a 6-speed manual transmission and adjustable damping (EDC) to the 5 Series range. There was an unusually large range of engines fitted over its lifetime as nine different engine families were used. These consisted of straight-four, straight-six and V8 engines. The E34 M5 is powered by the S38 straight-six engine and was produced in sedan and wagon body styles.
  • 12.1K
  • 31 Oct 2022
Topic Review
Sensible and Latent Heat Thermal Energy Storage
Sharing renewable energies, reducing energy consumption and optimizing energy management in an attempt to limit environmental problems (air pollution, global warming, acid rain, etc.) has today become a genuine concern of scientific engineering research. Furthermore, with the drastic growth of requirements in building and industrial worldwide sectors, the need for proper techniques that allow enhancement in the thermal performance of systems is increasingly being addressed. It is worth noting that using sensible and latent heat storage materials (SHSMs and phase change materials (PCMs)) for thermal energy storage mechanisms can meet requirements such as thermal comfort in buildings when selected correctly.
  • 12.1K
  • 29 Jul 2022
Topic Review
Catholic Church and Evolution
Early contributions to biology were made by Catholic scientists such as Jean-Baptiste Lamarck and the Augustinian monk Gregor Mendel. Since the publication of Charles Darwin's On the Origin of Species in 1859, the attitude of the Catholic Church on the theory of evolution has slowly been refined. For nearly a century, the papacy offered no authoritative pronouncement on Darwin's theories. In the 1950 encyclical Humani generis, Pope Pius XII confirmed that there is no intrinsic conflict between Christianity and the theory of evolution, provided that Christians believe that God created all things and that the individual soul is a direct creation by God and not the product of purely material forces. (As of 2013), the Church supports theistic evolution(ism), also known as evolutionary creation, although Catholics are free not to believe in any part of evolutionary theory. The Catholic Church holds no official position on the theory of creation or evolution, leaving the specifics of either theistic evolution or literal creationism to the individual within certain parameters established by the Church. According to the Catechism of the Catholic Church, any believer may accept either literal or special creation within the period of an actual six-day, twenty-four-hour period, or they may accept the belief that the earth evolved over time under the guidance of God. Catholicism holds that God initiated and continued the process of his evolutionary creation, that Adam and Eve were real people, and affirms that all humans, whether specially created or evolved, have and have always had specially created souls for each individual. Catholic schools in the United States and other countries teach evolution as part of their science curriculum. They teach the fact that evolution occurs and the modern evolutionary synthesis, which is the scientific theory that explains how evolution proceeds.
  • 12.1K
  • 31 Oct 2022
Topic Review
Multiverse (Religion)
The concept of a multiverse is explored in various religious cosmologies that propose that the totality of existence comprises multiple or infinitely many universes, including our own. Usually, such beliefs include a creation myth, a history, a worldview and a prediction of the eventual fate or destiny of the world. The worldview discusses the current organizational form of our universe and may contain references to other supernatural world or worlds. These references have aided several esoteric practices, including contacts with spirit worlds, and activities concerning personal or inner spiritual development. Many of these worlds include an afterlife existence, which may be very different from existence in the physical plane or the world of the living; common afterlife realms include heaven, hell, and realm of the dead. Eschatological scenarios may include a new, different world after the end time of the current world. For example, Hindu cosmology includes the idea of an infinite cycle of births and deaths and an infinite number of universes with each cycle lasting 8.64 billion years. The cosmological ideas in various religious traditions have clearly evolved in time due to the introduction of new concepts and the exchange of ideas with other cultures. Nevertheless, perennial philosophers believe that these traditions all share a single supernatural truth or origin.
  • 12.1K
  • 21 Nov 2022
Topic Review
Chinese Swords
Historically, all Chinese swords are classified into two types, jian and dao. Jians are double-edged straight swords while daos are single-edged, and mostly curved from the Song dynasty forward. The jian has been translated at times as a long sword, and the dao a saber or a knife. Bronze jians appeared during the Western Zhou period and switched to wrought iron and steel during the late Warring States period. In modern times, the ceremonial commissioned officer's sword of the Chinese navy has been patterned after the traditional jian since 2008. Other than specialized weapons like the Divided Dao, Chinese swords are usually 70–110 cm (28–43 in) in length, although longer swords have been found on occasion. Outside of China, Chinese swords were also used in Japan from the third to the sixth century AD, but were replaced with Korean and native Japanese swords by the middle Heian era.
  • 12.0K
  • 30 Sep 2022
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