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Explicit Memory
Explicit memory (or declarative memory) is one of the two main types of long-term human memory, the other of which is implicit memory. Explicit memory is the conscious, intentional recollection of factual information, previous experiences, and concepts. This type of memory is dependent upon three processes: acquisition, consolidation, and retrieval. Explicit memory can be divided into two categories: episodic memory, which stores specific personal experiences, and semantic memory, which stores factual information. Explicit memory requires gradual learning, with multiple presentations of a stimulus and response. Procedural memory, a type of implicit (or non-declarative) memory, refers to unconscious memories such as skills (e.g. knowing how to get dressed, eat, drive, ride a bicycle without having to re-learn the skill each time). Procedural memory learns rule-like relations, whereas explicit memory learns relations that are arbitrary. Unlike explicit memory, procedural memory learns rapidly, even from a single stimulus, and it is influenced by other mental systems. Sometimes a distinction is made between explicit memory and declarative memory. In such cases, explicit memory relates to any kind of conscious memory, and declarative memory relates to any kind of memory that can be described in words; however, if it is assumed that a memory cannot be described without being conscious and vice versa, then the two concepts are identical.
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  • 23 Nov 2022
Topic Review
Bible Belt
The Bible Belt is a region of the Southern United States in which socially conservative Protestant Christianity plays a strong role in society and politics, and church attendance across the denominations is generally higher than the nation's average. The region contrasts with the religiously diverse Midwest and Great Lakes, and the Mormon corridor in Utah and southern Idaho. Whereas the states with the highest percentage of residents identifying as non-religious are in the West and New England regions of the United States (with Vermont at 37%, ranking the highest), in the Bible Belt state of Alabama it is just 12%, and Tennessee has the highest proportion of evangelical Protestants, at 52%. The evangelical influence is strongest in northern Georgia, Tennessee , Alabama, Mississippi, North Carolina, southern and western Virginia, West Virginia, the Upstate region of South Carolina, and East Texas . The earliest known usage of the term "Bible Belt" was by American journalist and social commentator H. L. Mencken, who in 1924 wrote in the Chicago Daily Tribune: "The old game, I suspect, is beginning to play out in the Bible Belt." In 1927, Mencken claimed the term as his invention. The term is now also used in other countries for regions with higher religious doctrine adoption.
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  • 24 Nov 2022
Topic Review
WD40 Repeat
The WD40 repeat (also known as the WD or beta-transducin repeat) is a short structural motif of approximately 40 amino acids, often terminating in a tryptophan-aspartic acid (W-D) dipeptide. Tandem copies of these repeats typically fold together to form a type of circular solenoid protein domain called the WD40 domain.
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  • 23 Nov 2022
Topic Review
Volcanology of Mars
Volcanic activity, or volcanism, has played a significant role in the geologic evolution of Mars. Scientists have known since the Mariner 9 mission in 1972 that volcanic features cover large portions of the Martian surface. These features include extensive lava flows, vast lava plains, and the largest known volcanoes in the Solar System. Martian volcanic features range in age from Noachian (>3.7 billion years) to late Amazonian (< 500 million years), indicating that the planet has been volcanically active throughout its history, and some speculate it probably still is so today. Both Earth and Mars are large, differentiated planets built from similar chondritic materials. Many of the same magmatic processes that occur on Earth also occurred on Mars, and both planets are similar enough compositionally that the same names can be applied to their igneous rocks and minerals. Volcanism is a process in which magma from a planet's interior rises through the crust and erupts on the surface. The erupted materials consist of molten rock (lava), hot fragmental debris (tephra or ash), and gases. Volcanism is a principal way that planets release their internal heat. Volcanic eruptions produce distinctive landforms, rock types, and terrains that provide a window on the chemical composition, thermal state, and history of a planet's interior. Magma is a complex, high-temperature mixture of molten silicates, suspended crystals, and dissolved gases. Magma on Mars likely ascends in a similar manner to that on Earth. It rises through the lower crust in diapiric bodies that are less dense than the surrounding material. As the magma rises, it eventually reaches regions of lower density. When the magma density matches that of the host rock, buoyancy is neutralized and the magma body stalls. At this point, it may form a magma chamber and spread out laterally into a network of dikes and sills. Subsequently, the magma may cool and solidify to form intrusive igneous bodies (plutons). Geologists estimate that about 80% of the magma generated on Earth stalls in the crust and never reaches the surface. As magma rises and cools, it undergoes many complex and dynamic compositional changes. Heavier minerals may crystallize and settle to the bottom of the magma chamber. The magma may also assimilate portions of host rock or mix with other batches of magma. These processes alter the composition of the remaining melt, so that any magma reaching the surface may be chemically quite different from its parent melt. Magmas that have been so altered are said to be "evolved" to distinguish them from "primitive" magmas that more closely resemble the composition of their mantle source. (See igneous differentiation and fractional crystallization.) More highly evolved magmas are usually felsic, that is enriched in silica, volatiles, and other light elements compared to iron- and magnesium-rich (mafic) primitive magmas. The degree and extent to which magmas evolve over time is an indication of a planet's level of internal heat and tectonic activity. The Earth's continental crust is made up of evolved granitic rocks that developed through many episodes of magmatic reprocessing. Evolved igneous rocks are much less common on cold, dead bodies such as the Moon. Mars, being intermediate in size between the Earth and the Moon, is thought to be intermediate in its level of magmatic activity. At shallower depths in the crust, the lithostatic pressure on the magma body decreases. The reduced pressure can cause gases (volatiles), such as carbon dioxide and water vapor, to exsolve from the melt into a froth of gas bubbles. The nucleation of bubbles causes a rapid expansion and cooling of the surrounding melt, producing glassy shards that may erupt explosively as tephra (also called pyroclastics). Fine-grained tephra is commonly referred to as volcanic ash. Whether a volcano erupts explosively or effusively as fluid lava depends on the composition of the melt. Felsic magmas of andesitic and rhyolitic composition tend to erupt explosively. They are very viscous (thick and sticky) and rich in dissolved gases. Mafic magmas, on the other hand, are low in volatiles and commonly erupt effusively as basaltic lava flows. However, these are only generalizations. For example, magma that comes into sudden contact with groundwater or surface water may erupt violently in steam explosions called hydromagmatic (phreatomagmatic or phreatic) eruptions. Erupting magmas may also behave differently on planets with different interior compositions, atmospheres, and gravitational fields.
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  • 23 Nov 2022
Topic Review
List of Ariane Launches (2000–2009)
This is a list of launches performed by Ariane carrier rockets between 2000 and 2009. During this period, the Ariane 4 was retired from service in favour of the Ariane 5.
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  • 23 Nov 2022
Topic Review
Medical Sign
A medical sign is an objective indication of a disease, injury, or abnormal physiological state that may be detected during the physical examination of a patient. These signs can be detectable by anyone, e.g. the temperature or blood pressure of the patient, skin that is redder than usual, or a bruise; others may have no meaning to the patient or may even go completely unnoticed. Medical signs assist a healthcare provider to reach an accurate diagnosis. A symptom is something, such as pain or dizziness, experienced by the patient. Signs and symptoms are not mutually exclusive. In other words, many symptoms such as feeling hot, are associated with a medical sign such as a thermometer reading showing an above average body temperature. Symptoms and signs are often nonspecific, but certain combinations can be suggestive of certain diagnoses, helping to narrow down what may be wrong. In other cases they are specific even to the point of being pathognomonic. Examples of signs include elevated blood pressure, clubbing of the ends of fingers as a sign of lung disease, staggering gait, and arcus senilis of the eyes. In medicine, a sign is distinguished from an indication; a specific reason for using a treatment.
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  • 23 Nov 2022
Topic Review
Pareto-Efficient Envy-Free Division
Efficiency and fairness are two major goals of welfare economics. Given a set of resources and a set of agents, the goal is to divide the resources among the agents in a way that is both Pareto efficient (PE) and envy-free (EF). The goal was first defined by David Schmeidler and Menahem Yaari. Later, the existence of such allocations has been proved under various conditions.
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  • 23 Nov 2022
Topic Review
Non-Deterministic Turing Machine
In theoretical computer science, a Turing machine is a theoretical machine that is used in thought experiments to examine the abilities and limitations of computers.
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  • 28 Nov 2022
Topic Review
Workplace Relationships
Workplace relationships are unique interpersonal relationships with important implications for the individuals in those relationships, and the organizations in which the relationships exist and develop. Workplace relationships directly affect a worker's ability and drive to succeed. These connections are multifaceted, can exist in and out of the organization, and be both positive and negative. One such detriment lies in the nonexistence of workplace relationships, which can lead to feelings of loneliness. Workplace relationships are not limited to friendships, but also include superior-subordinate, romantic, and family relationships.
  • 1.8K
  • 23 Nov 2022
Topic Review
Bootstrapping
In finance, bootstrapping is a method for constructing a (zero-coupon) fixed-income yield curve from the prices of a set of coupon-bearing products, e.g. bonds and swaps. A bootstrapped curve, correspondingly, is one where the prices of the instruments used as an input to the curve, will be an exact output, when these same instruments are valued using this curve. Here, the term structure of spot returns is recovered from the bond yields by solving for them recursively, by forward substitution: this iterative process is called the bootstrap method. The usefulness of bootstrapping is that using only a few carefully selected zero-coupon products, it becomes possible to derive par swap rates (forward and spot) for all maturities given the solved curve.
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  • 24 Nov 2022
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