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23,483 | # Philosophy of perception
## Spatial representation {#spatial_representation}
An aspect of perception that is common to both realists and anti-realists is the idea of mental or perceptual space. David Hume concluded that things appear extended because they have attributes of colour and solidity. A popular modern phi... | 334 | Philosophy of perception | 2 |
23,484 | # Proper name (philosophy)
In the philosophy of language, a **proper name**`{{snd}}`{=mediawiki} examples include a name of a specific person or place`{{snd}}`{=mediawiki} is a name which ordinarily is taken to uniquely identify its referent in the world. As such it presents particular challenges for theories of meani... | 551 | Proper name (philosophy) | 0 |
23,484 | # Proper name (philosophy)
## Theories
Many theories have been proposed about proper names, each attempting to solve the problems of reference and identity inherent in the concept.
### Millian theory {#millian_theory}
John Stuart Mill distinguished between connotative and denotative meaning, and argued that proper ... | 933 | Proper name (philosophy) | 1 |
23,484 | # Proper name (philosophy)
## Theories
### Continental philosophy {#continental_philosophy}
Outside of the analytic tradition, few continental philosophers have approached the proper name as a philosophical problem. In *Of Grammatology,* Jacques Derrida specifically refutes the idea that proper names stand outside of... | 108 | Proper name (philosophy) | 2 |
23,490 | # Political spectrum
A **political spectrum** is a system to characterize and classify different political positions in relation to one another. These positions sit upon one or more geometric axes that represent independent political dimensions. The expressions **political compass** and **political map** are used to r... | 396 | Political spectrum | 0 |
23,490 | # Political spectrum
## Academic investigation {#academic_investigation}
For almost a century, social scientists have considered the problem of how to best describe political variation.
### Leonard W. Ferguson {#leonard_w._ferguson}
In 1950, Leonard W. Ferguson analyzed political values using ten scales measuring a... | 918 | Political spectrum | 1 |
23,490 | # Political spectrum
## Academic investigation {#academic_investigation}
### Hans Eysenck {#hans_eysenck}
#### Subsequent criticism of Eysenck\'s research {#subsequent_criticism_of_eysencks_research}
Eysenck\'s conception of tough-mindedness has been criticized for a number of reasons.
- Virtually no values were f... | 601 | Political spectrum | 2 |
23,490 | # Political spectrum
## Academic investigation {#academic_investigation}
### Later research {#later_research}
In further research, Eysenck refined his methodology to include more questions on economic issues. Doing this, he revealed a split in the left--right axis between social policy and economic policy, with a pre... | 277 | Political spectrum | 3 |
23,490 | # Political spectrum
## Other double-axis models {#other_double_axis_models}
### Greenberg and Jonas: left--right, ideological rigidity {#greenberg_and_jonas_leftright_ideological_rigidity}
In a 2003 *Psychological Bulletin* paper, Jeff Greenberg and Eva Jonas posit a model comprising the standard left--right axis a... | 897 | Political spectrum | 4 |
23,490 | # Political spectrum
## Spatial model {#spatial_model}
The spatial model of voting plots voters and candidates in a multi-dimensional space where each dimension represents a single political issue sub-component of an issue, or candidate attribute. Voters are then modeled as having an \"ideal point\" in this space and... | 1,273 | Political spectrum | 5 |
23,490 | # Political spectrum
## Biological variables {#biological_variables}
A number of studies have found that biology can be linked with political orientation. Many of the studies linking biology to politics remain controversial and unreplicated, although the overall body of evidence is growing.
Studies have found that s... | 299 | Political spectrum | 6 |
23,496 | # Pregnancy (mammals)
In mammals, **pregnancy** is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female\'s uterus, and ends once it leaves the uterus.
## Fertilization and implan... | 960 | Pregnancy (mammals) | 0 |
23,497 | # Paroxysmal attack
**Paroxysmal attacks** or **paroxysms** are a sudden recurrence or intensification of symptoms, such as a spasm or seizure. These short, frequent symptoms can be observed in various clinical conditions. They are usually associated with multiple sclerosis or pertussis, but they may also be observed ... | 226 | Paroxysmal attack | 0 |
23,511 | # Point-to-Point Protocol
In computer networking, **Point-to-Point Protocol** (**PPP**) is a data link layer (layer 2) communication protocol between two routers directly without any host or any other networking in between. It can provide loop detection, authentication, transmission encryption, and data compression.
... | 1,142 | Point-to-Point Protocol | 0 |
23,511 | # Point-to-Point Protocol
## PPP frame {#ppp_frame}
### Structure
PPP frames are variants of HDLC frames:
Name Number of bytes Description
---------------------- ---------------------- ------------------------------------------
Flag 1 0x7E, the b... | 899 | Point-to-Point Protocol | 1 |
23,511 | # Point-to-Point Protocol
## Tunnels
----------------- ------------------------- ------ ------ ----- ----- -----
*Application* FTP SMTP HTTP ... DNS ...
*Transport* TCP UDP
*Network* IP ... | 331 | Point-to-Point Protocol | 2 |
23,519 | # Paul Valéry
**Ambroise Paul Toussaint Jules Valéry** (`{{IPA|fr|pɔl valeʁi|lang}}`{=mediawiki}; 30 October 1871 -- 20 July 1945) was a French poet, essayist, and philosopher.
In addition to his poetry and fiction (drama and dialogues), his interests included aphorisms on art, history, letters, music, and current ev... | 675 | Paul Valéry | 0 |
23,519 | # Paul Valéry
## Work
### The great silence {#the_great_silence}
Valéry is best known as a poet, and he is sometimes considered to be the last of the French symbolists. However, he published fewer than a hundred poems, and none of them drew much attention. On the night of 4 October 1892, during a heavy storm, Paul V... | 924 | Paul Valéry | 1 |
23,519 | # Paul Valéry
## In other literature {#in_other_literature}
One of three epigraphs in Cormac McCarthy\'s novel *Blood Meridian* is from Valéry\'s \"Writing at the Yalu River\" (1895): \"Your ideas are terrifying and your hearts are faint. Your acts of pity and cruelty are absurd, committed with no calm, as if they we... | 304 | Paul Valéry | 2 |
23,519 | # Paul Valéry
## Selected works {#selected_works}
- *Conte de nuits* (1888)
- *Paradoxe sur l'architecte* (1891)
- *Introduction à la méthode de Léonard de Vinci* (1895)
- *La soirée avec monsieur Teste* (1896)
- *La Jeune Parque* (1917)
- *Album des vers anciens* (1920)
- *Le cimetière marin* (1920)
- ... | 623 | Paul Valéry | 3 |
23,528 | # Pianist
A **pianist** (`{{IPAc-en|US|p|iː|ˈ|æ|n|ɪ|s|t}}`{=mediawiki} `{{respell|pee|AN|ist}}`{=mediawiki}, `{{small|also}}`{=mediawiki} `{{IPAc-en|ˈ|p|iː|ə|n|ɪ|s|t}}`{=mediawiki} `{{respell|PEE|ə|nist}}`{=mediawiki}) is a musician who plays the piano. A pianist\'s repertoire may include music from a diverse variety ... | 817 | Pianist | 0 |
23,531 | # Portability (social security)
The **portability of social security benefits** is the ability of workers to preserve, maintain, and transfer acquired social security rights and social security rights in the process of being acquired from one private, occupational, or public social security scheme to another. Social s... | 251 | Portability (social security) | 0 |
23,534 | # Percopsiformes
The **Percopsiformes** `{{IPAc-en|p|ɜːr|ˈ|k|ɒ|p|s|ᵻ|f|ɔːr|m|iː|z}}`{=mediawiki} are a small order of freshwater teleost fishes measuring less than 20 cm in length, comprising the trout-perch and its allies. It contains just ten extant species, grouped into seven genera and three families. Five of thes... | 238 | Percopsiformes | 0 |
23,539 | # Probability axioms
The standard **probability axioms** are the foundations of probability theory introduced by Russian mathematician Andrey Kolmogorov in 1933. These axioms remain central and have direct contributions to mathematics, the physical sciences, and real-world probability cases.
There are several other (... | 281 | Probability axioms | 0 |
23,539 | # Probability axioms
## Consequences
From the Kolmogorov axioms, one can deduce other useful rules for studying probabilities. The proofs of these rules are a very insightful procedure that illustrates the power of the third axiom, and its interaction with the prior two axioms. Four of the immediate corollaries and t... | 670 | Probability axioms | 1 |
23,543 | # Probability distribution
Distribution}}
In probability theory and statistics, a **probability distribution** is a function that gives the probabilities of occurrence of possible **events** for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities o... | 669 | Probability distribution | 0 |
23,543 | # Probability distribution
## General probability definition {#general_probability_definition}
Let $(\Omega, \mathcal{F}, P)$ be a probability space, $(E, \mathcal{E})$ be a measurable space, and $X : \Omega \to E$ be a $(E, \mathcal{E})$-valued random variable. Then the **probability distribution** of $X$ is the pus... | 738 | Probability distribution | 1 |
23,543 | # Probability distribution
## Terminology
Some key concepts and terms, widely used in the literature on the topic of probability distributions, are listed below.
### Basic terms {#basic_terms}
- *Random variable*: takes values from a sample space; probabilities describe which values and set of values are more lik... | 781 | Probability distribution | 2 |
23,543 | # Probability distribution
## Discrete probability distribution {#discrete_probability_distribution}
A **discrete probability distribution** is the probability distribution of a random variable that can take on only a countable number of values (almost surely) which means that the probability of any event $E$ can be ... | 689 | Probability distribution | 3 |
23,543 | # Probability distribution
## Absolutely continuous probability distribution {#absolutely_continuous_probability_distribution}
An **absolutely continuous probability distribution** is a probability distribution on the real numbers with uncountably many possible values, such as a whole interval in the real line, and w... | 391 | Probability distribution | 4 |
23,543 | # Probability distribution
## Kolmogorov definition {#kolmogorov_definition}
In the measure-theoretic formalization of probability theory, a random variable is defined as a measurable function $X$ from a probability space $(\Omega, \mathcal{F}, \mathbb{P})$ to a measurable space $(\mathcal{X},\mathcal{A})$. Given tha... | 429 | Probability distribution | 5 |
23,543 | # Probability distribution
## Random number generation {#random_number_generation}
Most algorithms are based on a pseudorandom number generator that produces numbers $X$ that are uniformly distributed in the half-open interval `{{closed-open|0, 1}}`{=mediawiki}. These random variates $X$ are then transformed via some... | 339 | Probability distribution | 6 |
23,543 | # Probability distribution
## Common probability distributions and their applications {#common_probability_distributions_and_their_applications}
The concept of the probability distribution and the random variables which they describe underlies the mathematical discipline of probability theory, and the science of stat... | 897 | Probability distribution | 7 |
23,543 | # Probability distribution
## Common probability distributions and their applications {#common_probability_distributions_and_their_applications}
### Some specialized applications of probability distributions {#some_specialized_applications_of_probability_distributions}
- The cache language models and other statisti... | 192 | Probability distribution | 8 |
23,545 | # Psychological statistics
**Psychological statistics** is application of formulas, theorems, numbers and laws to psychology. Statistical methods for psychology include development and application statistical theory and methods for modeling psychological data. These methods include psychometrics, factor analysis, expe... | 636 | Psychological statistics | 0 |
23,545 | # Psychological statistics
## Factor analysis {#factor_analysis}
Factor analysis is at the core of psychological statistics. It has two schools: (1) Exploratory Factor analysis (2) Confirmatory Factor analysis.
### Exploratory factor analysis (EFA) {#exploratory_factor_analysis_efa}
The exploratory factor analysis ... | 266 | Psychological statistics | 1 |
23,545 | # Psychological statistics
## Experimental design {#experimental_design}
Experimental methods are very popular in psychology, going back more than 100 years. Experimental psychology is a sub-discipline of psychology . Statistical methods applied for designing and analyzing experimental psychological data include the ... | 278 | Psychological statistics | 2 |
23,558 | # Pangenesis
thumb\|upright=2\|Charles Darwin\'s pangenesis theory postulated that every part of the body emits tiny particles called gemmules which migrate to the gonads and are transferred to offspring. Gemmules were thought to develop into their associated body parts as offspring matures. The theory implied that ch... | 263 | Pangenesis | 0 |
23,558 | # Pangenesis
## Early history {#early_history}
Pangenesis was similar to ideas put forth by Hippocrates, Democritus and other pre-Darwinian scientists in proposing that the whole of parental organisms participate in heredity (thus the prefix *pan*). Darwin wrote that Hippocrates\' pangenesis was \"almost identical wi... | 677 | Pangenesis | 1 |
23,558 | # Pangenesis
## Theory
### Darwin
Darwin\'s pangenesis theory attempted to explain the process of sexual reproduction, inheritance of traits, and complex developmental phenomena such as cellular regeneration in a unified mechanistic structure. Longshan Liu wrote that in modern terms, pangenesis deals with issues of ... | 868 | Pangenesis | 2 |
23,558 | # Pangenesis
## Collapse
### Galton\'s experiments on rabbits {#galtons_experiments_on_rabbits}
Darwin\'s half-cousin Francis Galton conducted wide-ranging inquiries into heredity which led him to refute Charles Darwin\'s hypothetical theory of pangenesis. In consultation with Darwin, he set out to see if gemmules w... | 401 | Pangenesis | 3 |
23,558 | # Pangenesis
## Collapse
### After pangenesis {#after_pangenesis}
Darwin\'s pangenesis theory was widely criticised, in part for its Lamarckian premise that parents could pass on traits acquired in their lifetime. Conversely, the neo-Lamarckians of the time seized upon pangenesis as evidence to support their case. It... | 433 | Pangenesis | 4 |
23,562 | # Perissodactyla
**Perissodactyla** (`{{IPAc-en|p|ə|ˌ|r|ɪ|s|oʊ|ˈ|d|æ|k|t|ᵻ|l|ə}}`{=mediawiki}, `{{etymology|grc|''περισσός'', perissós|odd||''δάκτυλος'', dáktylos|finger, toe}}`{=mediawiki}), or **odd-toed ungulates**, is an order of ungulates. The order includes about 17 living species divided into three families: Eq... | 524 | Perissodactyla | 0 |
23,562 | # Perissodactyla
## Anatomy
### Skull and teeth {#skull_and_teeth}
Odd-toed ungulates have a long upper jaw with an extended diastema between the front and cheek teeth, giving them an elongated head. The various forms of snout between families are due to differences in the form of the premaxilla. The lacrimal bone ha... | 767 | Perissodactyla | 1 |
23,562 | # Perissodactyla
## Lifestyle and diet {#lifestyle_and_diet}
Perissodactyls inhabit a number of different habitats, leading to different lifestyles. Tapirs are solitary and inhabit mainly tropical rainforests. Rhinos tend to live alone in rather dry savannas, and in Asia, wet marsh or forest areas. Horses inhabit ope... | 660 | Perissodactyla | 2 |
23,562 | # Perissodactyla
## Taxonomy
### Modern members {#modern_members}
Odd-toed ungulates comprise three living families with around 17 species---in horses, however, the exact count is still controversial. Rhinos and tapirs are more closely related to each other than to horses. According to molecular genetic analysis, the... | 591 | Perissodactyla | 3 |
23,562 | # Perissodactyla
## Taxonomy
### Prehistoric members {#prehistoric_members}
There are many perissodactyl fossils of multivariant form. The major lines of development include the following groups:
- Brontotherioidea were among the earliest known large mammals, consisting of the families of Brontotheriidae (synonym ... | 567 | Perissodactyla | 4 |
23,562 | # Perissodactyla
## Taxonomy
### Higher classification of perissodactyls {#higher_classification_of_perissodactyls}
<table>
<caption>Internal classification of Perissodactyla</caption>
<tbody>
<tr class="odd">
<td><p>{{Clade|style=white-space:nowrap;font-size:75%;line-height:100%</p></td>
<td><p>label1=<strong>Periss... | 516 | Perissodactyla | 5 |
23,562 | # Perissodactyla
## Evolutionary history {#evolutionary_history}
### Origins
The evolutionary development of Perissodactyla is well documented in the fossil record. Numerous finds are evidence of the adaptive radiation of this group, which was once much more varied and widely dispersed. *Radinskya* from the late Pal... | 809 | Perissodactyla | 6 |
23,562 | # Perissodactyla
## Research history {#research_history}
In 1758, in his seminal work *Systema Naturae*, Linnaeus (1707--1778) classified horses (*Equus*) together with hippos (*Hippopotamus*). At that time, this category also included the tapirs (*Tapirus*), more precisely the lowland or South American tapir (*Tapir... | 407 | Perissodactyla | 7 |
23,562 | # Perissodactyla
## Interactions with humans {#interactions_with_humans}
The domestic horse and the donkey play an important role in human history, particularly as transport, work and pack animals. The domestication of both species began several millennia BCE. Due to the motorisation of agriculture and the spread of ... | 386 | Perissodactyla | 8 |
23,565 | # Pai gow
thumb\|right\|upright=1.5\|A set of 32 Chinese dominoes. The top two rows of tiles show the eleven matching pairs, in descending value from left to right. Below them are five non-matching pairs, worth less than the matching pairs, and also in descending value from left to right. The *Gee Joon* (\"Supreme\") ... | 288 | Pai gow | 0 |
23,565 | # Pai gow
## Rules
### Starting
Tiles are shuffled on the table and are arranged into eight face-down stacks of four tiles each in an assembly known as the *woodpile*. Individual stacks or tiles may then be moved in specific ways to rearrange the woodpile, after which the players place their bets.
Next, each player... | 1,127 | Pai gow | 1 |
23,565 | # Pai gow
## Rules
### Scoring
#### Modular arithmetic {#modular_arithmetic}
------- ------------------------- ------------------------- --------------------
Tiles Total value
Ex. 1 frameless\|upright=0.12 frameless\|upright=0.12 4+5=9
1+3=4 ... | 459 | Pai gow | 2 |
23,565 | # Pai gow
## Strategy
+---------+-------------------------------------------------+------------------------+-------------------------------------------------+------------------------+-------+
| Deal | frameless\|upright=0.2 | frameless\|upright=0.2 | frameless\|upright=0.2 ... | 342 | Pai gow | 3 |
23,565 | # Pai gow
## In popular culture {#in_popular_culture}
The film *Premium Rush* (2012) features Pai Gow play as an integral plot element | 22 | Pai gow | 4 |
23,577 | # Partial function
In mathematics, a **partial function** `{{mvar|f}}`{=mediawiki} from a set `{{mvar|X}}`{=mediawiki} to a set `{{mvar|Y}}`{=mediawiki} is a function from a subset `{{mvar|S}}`{=mediawiki} of `{{mvar|X}}`{=mediawiki} (possibly the whole `{{mvar|X}}`{=mediawiki} itself) to `{{mvar|Y}}`{=mediawiki}. The... | 411 | Partial function | 0 |
23,577 | # Partial function
## Basic concepts {#basic_concepts}
--
--
A partial function arises from the consideration of maps between two sets `{{mvar|X}}`{=mediawiki} and `{{mvar|Y}}`{=mediawiki} that may not be defined on the entire set `{{mvar|X}}`{=mediawiki}. A common example is the square root operation on the rea... | 457 | Partial function | 1 |
23,577 | # Partial function
## Discussion and examples {#discussion_and_examples}
The first diagram at the top of the article represents a partial function that is `{{em|not}}`{=mediawiki} a function since the element 1 in the left-hand set is not associated with anything in the right-hand set. Whereas, the second diagram rep... | 729 | Partial function | 2 |
23,589 | # Parable of the Pearl
The **Parable of the Pearl** (also called the **Pearl of Great Price**) is one of the parables of Jesus Christ. It appears in Matthew 13 and illustrates the great value of the Kingdom of Heaven.
This is the penultimate parable in Matthew 13, coming just before the Parable of the Dragnet. It imm... | 538 | Parable of the Pearl | 0 |
23,589 | # Parable of the Pearl
## Commentary from the Church Fathers {#commentary_from_the_church_fathers}
John Chrysostom: \"The Gospel preaching not only offers manifold gain as a treasure, but is precious as a pearl; wherefore after the parable concerning the treasure, He gives that concerning the pearl. And in preaching,... | 594 | Parable of the Pearl | 1 |
23,589 | # Parable of the Pearl
## Gospel of Thomas {#gospel_of_thomas}
A version of the parable appears in the Gnostic Gospel of Thomas (Saying 76): `{{Blockquote|Jesus said, "The Father's kingdom is like a merchant who had a supply of merchandise and found a pearl. That merchant was prudent; he sold the merchandise and boug... | 222 | Parable of the Pearl | 2 |
23,597 | # Physiology
*Physiology* (journal)}} thumb\|upright=1.5\|Oil painting depicting Claude Bernard, the father of modern physiology, with his pupils `{{TopicTOC-Biology}}`{=mediawiki}
**Physiology** (`{{IPAc-en|ˌ|f|ɪ|z|i|ˈ|ɒ|l|ə|dʒ|i}}`{=mediawiki}; `{{etymology|grc|''{{wikt-lang|grc|φύσις}}'' ({{grc-transl|φύσις}})|nat... | 406 | Physiology | 0 |
23,597 | # Physiology
## Subdisciplines
There are many ways to categorize the subdisciplines of physiology:
- based on the taxa studied: human physiology, animal physiology, plant physiology, microbial physiology, viral physiology
- based on the level of organization: cell physiology, molecular physiology, systems physio... | 522 | Physiology | 1 |
23,597 | # Physiology
## History
### The classical era {#the_classical_era}
The study of human physiology as a medical field originates in classical Greece, at the time of Hippocrates (late 5th century BC). Outside of Western tradition, early forms of physiology or anatomy can be reconstructed as having been present at aroun... | 1,013 | Physiology | 2 |
23,597 | # Physiology
## Notable physiologists {#notable_physiologists}
### Women in physiology {#women_in_physiology}
Initially, women were largely excluded from official involvement in any physiological society. The American Physiological Society, for example, was founded in 1887 and included only men in its ranks. In 1902... | 440 | Physiology | 3 |
23,612 | # Postmodern philosophy
**Postmodern philosophy** is a philosophical movement that arose in the second half of the 20th century as a critical response to assumptions allegedly present in modernist philosophical ideas regarding culture, identity, history, or language that were developed during the 18th-century Age of E... | 680 | Postmodern philosophy | 0 |
23,612 | # Postmodern philosophy
## Postmodern philosophers {#postmodern_philosophers}
### Michel Foucault {#michel_foucault}
Michel Foucault is often cited as an early postmodernist although he personally rejected that label. Following Nietzsche, Foucault argued that knowledge is produced through the operations of *power*, ... | 717 | Postmodern philosophy | 1 |
23,612 | # Postmodern philosophy
## Criticism
Some criticism responds to postmodernist skepticism towards objective reality and claims that truth and morality are relative, including the argument that this relativism is self-contradictory. In part in reference to postmodernism, conservative English philosopher Roger Scruton w... | 320 | Postmodern philosophy | 2 |
23,619 | # Pressure
**Pressure** (symbol: *p* or *P*) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled *gage* pressure) is the pressure relative to the ambient pressure.
Various units are used to express pressure. Some of these deri... | 526 | Pressure | 0 |
23,619 | # Pressure
## Definition
### Units
The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m^2^, or kg·m^−1^·s^−2^). This name for the unit was added in 1971; before that, pressure in SI was expressed in newtons per square metre.
Other units of pressure, such as pounds per square inch (l... | 879 | Pressure | 1 |
23,619 | # Pressure
## Definition
### Examples
As an example of varying pressures, a finger can be pressed against a wall without making any lasting impression; however, the same finger pushing a thumbtack can easily damage the wall. Although the force applied to the surface is the same, the thumbtack applies more pressure be... | 452 | Pressure | 2 |
23,619 | # Pressure
## Definition
### Scalar nature {#scalar_nature}
In a static gas, the gas as a whole does not appear to move. The individual molecules of the gas, however, are in constant random motion. Because there are an extremely large number of molecules and because the motion of the individual molecules is random in... | 391 | Pressure | 3 |
23,619 | # Pressure
## Types
### Fluid pressure {#fluid_pressure}
*Fluid pressure* is most often the compressive stress at some point within a fluid. (The term *fluid* refers to both liquids and gases -- for more information specifically about liquid pressure, see section below.) thumb\|upright=1.2\|Water escapes at high spe... | 390 | Pressure | 4 |
23,619 | # Pressure
## Types
### Negative pressures {#negative_pressures}
While *pressures* are, in general, positive, there are several situations in which negative pressures may be encountered:
- When dealing in relative (gauge ) pressures. For instance, an absolute pressure of 80 kPa may be described as a gauge pressure... | 837 | Pressure | 5 |
23,619 | # Pressure
## Types
### Liquid pressure {#liquid_pressure}
When a person swims under the water, water pressure is felt acting on the person\'s eardrums. The deeper that person swims, the greater the pressure. The pressure felt is due to the weight of the water above the person. As someone swims deeper, there is more ... | 1,000 | Pressure | 6 |
23,619 | # Pressure
## Types
### Direction of liquid pressure {#direction_of_liquid_pressure}
An experimentally determined fact about liquid pressure is that it is exerted equally in all directions. If someone is submerged in water, no matter which way that person tilts their head, the person will feel the same amount of wate... | 431 | Pressure | 7 |
23,621 | # Polygon
In geometry, a **polygon** (`{{IPAc-en|ˈ|p|ɒ|l|ɪ|ɡ|ɒ|n}}`{=mediawiki}) is a plane figure made up of line segments connected to form a closed polygonal chain.
The segments of a closed polygonal chain are called its *edges* or *sides*. The points where two edges meet are the polygon\'s *vertices* or *corners*... | 266 | Polygon | 0 |
23,621 | # Polygon
## Classification
### Number of sides {#number_of_sides}
Polygons are primarily classified by the number of sides.
### Convexity and intersection {#convexity_and_intersection}
Polygons may be characterized by their convexity or type of non-convexity:
- Convex: any line drawn through the polygon (and n... | 423 | Polygon | 1 |
23,621 | # Polygon
## Properties and formulas {#properties_and_formulas}
thumb\|upright=1.0\|Partitioning an *n*-gon into `{{nowrap|''n'' − 2}}`{=mediawiki} triangles Euclidean geometry is assumed throughout.
### Angles
Any polygon has as many corners as it has sides. Each corner has several angles. The two most important o... | 1,145 | Polygon | 2 |
23,621 | # Polygon
## Generalizations
The idea of a polygon has been generalized in various ways. Some of the more important include:
- A spherical polygon is a circuit of arcs of great circles (sides) and vertices on the surface of a sphere. It allows the digon, a polygon having only two sides and two corners, which is im... | 305 | Polygon | 3 |
23,621 | # Polygon
## Naming
The word *polygon* comes from Late Latin *polygōnum* (a noun), from Greek πολύγωνον (*polygōnon/polugōnon*), noun use of neuter of πολύγωνος (*polygōnos/polugōnos*, the masculine adjective), meaning \"many-angled\". Individual polygons are named (and sometimes classified) according to the number o... | 713 | Polygon | 4 |
23,621 | # Polygon
## In nature {#in_nature}
Polygons appear in rock formations, most commonly as the flat facets of crystals, where the angles between the sides depend on the type of mineral from which the crystal is made.
Regular hexagons can occur when the cooling of lava forms areas of tightly packed columns of basalt, w... | 342 | Polygon | 5 |
23,631 | # Primary mirror
A **primary mirror** (or **primary**) is the principal light-gathering surface (the objective) of a reflecting telescope.
## Description
The primary mirror of a reflecting telescope is a spherical, parabolic, or hyperbolic shaped disks of polished reflective metal (speculum metal up to the mid 19th ... | 374 | Primary mirror | 0 |
23,636 | # Perimeter
A **perimeter** is the length of a closed boundary that encompasses, surrounds, or outlines either a two-dimensional shape or a one-dimensional line. The perimeter of a circle or an ellipse is called its circumference.
Calculating the perimeter has several practical applications. A calculated perimeter is... | 401 | Perimeter | 0 |
23,636 | # Perimeter
## Polygons
Polygons are fundamental to determining perimeters, not only because they are the simplest shapes but also because the perimeters of many shapes are calculated by approximating them with sequences of polygons tending to these shapes. The first mathematician known to have used this kind of reas... | 870 | Perimeter | 1 |
23,636 | # Perimeter
## Etymology
The word comes from the Greek περίμετρος *perimetros*, from περί *peri* \"around\" and μέτρον *metron* \"measure\" | 20 | Perimeter | 2 |
23,640 | # Pentose
In chemistry, a **pentose** is a monosaccharide (simple sugar) with five carbon atoms. The chemical formula of many pentoses is `{{chem|C|5|H|10|O|5}}`{=mediawiki}, and their molecular weight is 150.13 g/mol.
Pentoses are very important in biochemistry. Ribose is a constituent of RNA, and the related molecu... | 660 | Pentose | 0 |
23,640 | # Pentose
## Properties
In the cell, pentoses have a higher metabolic stability than hexoses.
A polymer composed of pentose sugars is called a pentosan.
### Tests for pentoses {#tests_for_pentoses}
The most important tests for pentoses rely on converting the pentose to furfural, which then reacts with a chromophor... | 104 | Pentose | 1 |
23,652 | # Purine
**Purine** is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, **purines**, which include substituted purines and their tautomers. They are the most widely occurring n... | 789 | Purine | 0 |
23,652 | # Purine
## Laboratory synthesis {#laboratory_synthesis}
In addition to *in vivo* synthesis of purines in purine metabolism, purine can also be synthesized artificially.
Purine is obtained in good yield when formamide is heated in an open vessel at 170 °C for 28 hours.
:
This reaction and others like it have be... | 214 | Purine | 1 |
23,654 | # Play-by-mail game
A **play-by-mail game** (also known as a **PBM game**, **PBEM game**, **turn-based game**, **turn based distance game**, or an **interactive strategy game**.) is a game played through postal mail, email, or other digital media. Correspondence chess and Go were among the first PBM games. *Diplomacy*... | 524 | Play-by-mail game | 0 |
23,654 | # Play-by-mail game
## History
The earliest play-by-mail games developed as a way for geographically separated gamers to compete with each other using postal mail. Chess and Go are among the oldest examples of this. In these two-player games, players sent moves directly to each other. Multi-player games emerged later... | 1,114 | Play-by-mail game | 1 |
23,654 | # Play-by-mail game
## History
Paul Brown, the president of Reality Simulations, Inc., estimated in 1988 that there were about 20,000 steady play-by-mail gamers, with potentially another 10--20,000 who tried PBM gaming but did not stay. Flying Buffalo Inc. conducted a survey of 167 of its players in 1984. It indicate... | 896 | Play-by-mail game | 2 |
23,654 | # Play-by-mail game
## Description
PBM games can include Combat, Diplomacy, Politics, Exploration, Economics, and Role-Playing, with combat a usual feature and open-ended games typically the most comprehensive. Jim Townsend identifies the two key figures in PBM games as the players and the moderators, the latter of w... | 1,017 | Play-by-mail game | 3 |
23,654 | # Play-by-mail game
## Description
### Closed versus open ended {#closed_versus_open_ended}
According to John Kevin Loth III, open-ended games do not end and there is no final objective or way to win the game. Jim Townsend adds that, \"players come and go, powers grow and diminish, alliances form and dissolve and so ... | 684 | Play-by-mail game | 4 |
23,654 | # Play-by-mail game
## Fiction
Besides articles and reviews on PBM games, authors have also published PBM fiction articles according to Shannon Muir. An early example called \"Scapegoat\" by Mike Horn appeared in the May--June 1984 issue of *Paper Mayhem* magazine. Examples include \"A Loaf of Bread\" by Suzanna Y. S... | 130 | Play-by-mail game | 5 |
23,661 | # Phutball
**Phutball** (short for **Philosopher\'s Football**) is a two-player abstract strategy board game described in Elwyn Berlekamp, John Horton Conway, and Richard K. Guy\'s *Winning Ways for your Mathematical Plays*.
## Rules
Phutball is played on the intersections of a 19×15 grid using one white stone and a... | 602 | Phutball | 0 |
23,669 | # Piers Anthony
**Piers Anthony Dillingham Jacob** (born August 6, 1934) is an American author in the science fiction and fantasy genres, publishing under the name **Piers Anthony**. He is best known for his long-running novel series set in the fictional realm of Xanth.
Many of his books have appeared on *The New Yor... | 763 | Piers Anthony | 0 |
23,669 | # Piers Anthony
## In other media {#in_other_media}
Act One of episode 470 of the radio program *This American Life* is an account of boyhood obsessions with Piers Anthony. The act is written and narrated by writer Logan Hill who, as a 12-year-old, was consumed with reading Anthony\'s novels. For a decade he felt he ... | 623 | Piers Anthony | 1 |
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