The quadrant theory is a theory of intelligent design describing that reality is organized around a pattern called the quadrant model pattern. Previous books discuss the nature of this pattern.
March 21 Facebook-11:00
Science Chapter
Physics Chapter
Qms Silicon controlled rectifiers have four layers. A silicon controlled rectifier or semiconductor-controlled rectifier is a four-layer solid-state current-controlling device. The name "silicon controlled rectifier" is General Electric's trade name for a type of thyristor. The SCR was developed by a team of power engineers led by Gordon Hall[1] and commercialized by Frank W. "Bill" Gutzwiller in 1957.
Some sources define silicon controlled rectifiers and thyristors as synonymous,[2] other sources define silicon controlled rectifiers as a proper subset of the set of thyristors, those being devices with at least four layers of alternating n- and p-type material.[3][4] According to Bill Gutzwiller, the terms "SCR" and "controlled rectifier" were earlier, and "thyristor" was applied later, as usage of the device spread internationally.[5]
SCRs are unidirectional devices (i.e. can conduct current only in one direction) as opposed to TRIACs, which are bidirectional (i.e. current can flow through them in either direction). SCRs can be triggered normally only by currents going into the gate as opposed to TRIACs, which can be triggered normally by either a positive or a negative current applied to its gate electrode.
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QMRMade in Italy brand has been used since 1980 to indicate the international uniqueness of Italy in four traditional industries: fashion, food, furniture and mechanical engineering (automobiles, industrial design, machineries and shipbuilding), in Italian also known as "Four A", Abbigliamento (clothes), Agroalimentare (food), Arredamento (furniture) and Automobili (automobiles). Italian products have often been associated with quality, high specialization and differentiation, elegance, and strong links to experienced and famous Italian industrial districts. Since 1999, Made in Italy has begun to be protected by associations such as Istituto per la Tutela dei Produttori Italiani (Institute for the Protection of the Italian Manufacturers) and regulated by the Italian law.[2][3]
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QMRIl Divo (Italian pronunciation: [il ˈdiːvo]) is a multinational classical crossover vocal group. The group originated in the UK in December 2003,[1] and is a vocal quartet composed of four male singers; Swiss Urs Buhler, Spaniard Carlos Marin, American David Miller, and Frenchman Sébastien Izambard.
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QMrThe fourth passive element, the memristor, was proposed by Leon Chua in a 1971 paper, but a physical component demonstrating memristance was not created until thirty-seven years later. It was reported on April 30, 2008, that a working memristor had been developed by a team at HP Labs led by scientist R. Stanley Williams.[2][3][4][5] With the advent of the memristor, each pairing of the four variables can now be related. Because memristors are time-variant by definition, they are not included in linear time-invariant (LTI) circuit models.[citation needed]
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Prior to the availability of integrated circuits, a bridge rectifier was constructed from "discrete components", i.e., separate diodes. Since about 1950, a single four-terminal component containing the four diodes connected in a bridge configuration became a standard commercial component and is now available with various voltage and current ratings.
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QMRA diode bridge is an arrangement of four (or more) diodes in a bridge circuit configuration that provides the same polarity of output for either polarity of input.
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QMRString theory is a set of attempts to model the four known fundamental interactions—gravitation, electromagnetism, strong nuclear force, weak nuclear force—together in one theory. This tries to resolve the alleged conflict between classical physics and quantum physics by elementary units—the one classical force: gravity, and a new quantum field theory of the other three fundamental forces.
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QMRThe four big kinds of anthropology are:
Archaeology - The study of how people lived in the past. Archaeologists learn from things people leave behind, like pottery, stone tools, or anything made or used by humans.
Physical anthropology - The study of human biology, including how people adapt to where they live and how bodies changed over time (evolution). Physical anthropologists also study non-human primates.
Linguistic anthropology - The study of how people speak and the words they use and how their language developed (evolved). Linguistic anthropology also studies how language changes what people think and how people change language.
Cultural anthropology - The study of how people live their lives now and how they may have lived in the past, including the tools they used and the food they obtained and ate. It is also related to sociology and social psychology.
Most people who study anthropology have some schoolwork in all four big kinds of anthropology but later study one or two areas primarily.
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QMrPhysics, a branch of science, is the study of all forces and their impacts on the environment. Modern physics connects ideas together about the four laws of symmetry and conservation (energy, momentum, charge, and parity). The word physics comes from the Greek word ἡ φύσις "nature".
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QMRFour-wire configuration[edit]
The four-wire resistance configuration increases the accuracy of measurement of resistance. Four-terminal sensing eliminates voltage drop in the measuring leads as a contribution to error. To increase accuracy further, any residual thermoelectric voltages generated by different wire types or screwed connections are eliminated by reversal of the direction of the 1 mA current and the leads to the DVM (Digital Voltmeter). The thermoelectric voltages will be produced in one direction only. By averaging the reversed measurements, the thermoelectric error voltages are cancelled out.[citation needed]
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QMRA four-wire terminating set (4WTS) is a balanced transformer used to perform a conversion between four-wire and two-wire operation in telecommunication systems.
For example, a 4-wire circuit may, by means of a 4-wire terminating set, be connected to a 2-wire telephone set. Also, a pair of 4-wire terminating sets may be used to introduce an intermediate 4-wire circuit into a 2-wire circuit, in which loop repeaters may be situated to amplify signals in each direction without positive feedback and oscillation.
The 4WTS differs from a simple hybrid coil in being equipped to adjust its impedance to maximize return loss.
Four-wire terminating sets were largely supplanted by resistance hybrids in the late 20th century.
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QMRIn telecommunication, a four-wire circuit is a two-way circuit using two paths so arranged that the respective signals are transmitted in one direction only by one path and in the other direction by the other path. Late in the 20th century, almost all connections between telephone exchanges were four-wire circuits, while conventional phone lines into residences and businesses were two-wire circuits.
The four-wire circuit gets its name from the fact that, historically, a balanced pair of conductors were used in each of two directions for full-duplex operation. The name may still be applied to, for example, optical fibers, even though only one fiber is required for transmission in each direction. A system can separate the frequency directions by frequency duplex and realize the benefits of a four-wire circuit even while the same wire pair is used in both directions.
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QMRThe behavior of a thermodynamic system is summarized in the laws of thermodynamics, which concisely are:
Zeroth law of thermodynamics
If A, B, C are thermodynamic systems such that A is in thermal equilibrium with B and B is in thermal equilibrium with C, then A is in thermal equilibrium with C.
The zeroth law is of importance in thermometry, because it implies the existence of temperature scales. In practice, C is a thermometer, and the zeroth law says that systems that are in thermodynamic equilibrium with each other have the same temperature. The law was actually the last of the laws to be formulated.
First law of thermodynamics
dU=\delta Q-\delta W\, where dU\, is the infinitesimal increase in internal energy of the system, \delta Q\, is the infinitesimal heat flow into the system, and \delta W\, is the infinitesimal work done by the system.
The first law is the law of conservation of energy. The symbol \delta instead of the plain d, originated in the work of German mathematician Carl Gottfried Neumann[1] and is used to denote an inexact differential and to indicate that Q and W are path-dependent (i.e., they are not state functions). In some fields such as physical chemistry, positive work is conventionally considered work done on the system rather than by the system, and the law is expressed as dU=\delta Q+\delta W.
Second law of thermodynamics
The entropy of an isolated system never decreases: dS \ge 0 for an isolated system.
A concept related to the second law which is important in thermodynamics is that of reversibility. A process within a given isolated system is said to be reversible if throughout the process the entropy never increases (i.e. the entropy remains unchanged).
Third law of thermodynamics
\, S=0 when \, T = 0
The third law of thermodynamics states that at the absolute zero of temperature, the entropy is zero for a perfect crystalline structure.
Onsager reciprocal relations – sometimes called the Fourth law of thermodynamics
\mathbf{J}_{u} = L_{uu}\, \nabla(1/T) - L_{ur}\, \nabla(m/T) \!
\mathbf{J}_{r} = L_{ru}\, \nabla(1/T) - L_{rr}\, \nabla(m/T) \!
The fourth law of thermodynamics is not yet an agreed upon law (many supposed variations exist); historically, however, the Onsager reciprocal relations have been frequently referred to as the fourth law.
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QMrThe Global Positioning System (GPS) is a space-based navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of at least four GPS satellites, three for the three space dimensions and one for the time dimension.
The GPS concept is based on time and the known position of specialized satellites. The satellites carry very stable atomic clocks that are synchronized to each other and to ground clocks. Any drift from true time maintained on the ground is corrected daily. Likewise, the satellite locations are known with great precision. GPS receivers have clocks as well; however, they are not synchronized with true time, and are less stable. GPS satellites continuously transmit their current time and position. A GPS receiver monitors multiple satellites and solves equations to determine the exact position of the receiver and its deviation from true time. At a minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and clock deviation from satellite time).
More detailed description[edit]
Each GPS satellite continually broadcasts a signal (carrier wave with modulation) that includes:
A pseudorandom code (sequence of ones and zeros) that is known to the receiver. By time-aligning a receiver-generated version and the receiver-measured version of the code, the time of arrival (TOA) of a defined point in the code sequence, called an epoch, can be found in the receiver clock time scale
A message that includes the time of transmission (TOT) of the code epoch (in GPS system time scale) and the satellite position at that time
Conceptually, the receiver measures the TOAs (according to its own clock) of four satellite signals. From the TOAs and the TOTs, the receiver forms four time of flight (TOF) values, which are (given the speed of light) approximately equivalent to receiver-satellite range differences. The receiver then computes its three-dimensional position and clock deviation from the four TOFs.
In practice the receiver position (in three dimensional Cartesian coordinates with origin at the Earth's center) and the offset of the receiver clock relative to the GPS time are computed simultaneously, using the navigation equations to process the TOFs.
The receiver's Earth-centered solution location is usually converted to latitude, longitude and height relative to an ellipsoidal Earth model. The height may then be further converted to height relative the geoid (e.g., EGM96) (essentially, mean sea level). These coordinates may be displayed, e.g. on a moving map display and/or recorded and/or used by some other system (e.g., a vehicle guidance system).
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QMrThe Global Positioning System (GPS) is a space-based navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of at least four GPS satellites, three for the three space dimensions and one for the time dimension
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QMRThe Four Great Inventions (simplified Chinese: 四大发明; traditional Chinese: 四大發明) are inventions from ancient China that are celebrated in Chinese culture for their historical significance and as symbols of ancient China's advanced science and technology.[1]
The Four Great Inventions are:
Compass[2]
Gunpowder[3]
Papermaking[4]
Printing[5]
These four discoveries had a large impact on the development of civilization throughout the world. However, some modern Chinese scholars have opined that other Chinese inventions were perhaps more sophisticated and had a greater impact on Chinese civilization – the Four Great Inventions serve merely to highlight the technological interaction between East and West.[6]
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QMRModern systems are more direct. The satellite broadcasts a signal that contains orbital data (from which the position of the satellite can be calculated) and the precise time the signal was transmitted. The orbital data is transmitted in a data message that is superimposed on a code that serves as a timing reference. The satellite uses an atomic clock to maintain synchronization of all the satellites in the constellation. The receiver compares the time of broadcast encoded in the transmission of three (at sea level) or four different satellites, thereby measuring the time-of-flight to each satellite. Several such measurements can be made at the same time to different satellites, allowing a continual fix to be generated in real time using an adapted version of trilateration: see GNSS positioning calculation for details.
Each distance measurement, regardless of the system being used, places the receiver on a spherical shell at the measured distance from the broadcaster. By taking several such measurements and then looking for a point where they meet, a fix is generated. However, in the case of fast-moving receivers, the position of the signal moves as signals are received from several satellites. In addition, the radio signals slow slightly as they pass through the ionosphere, and this slowing varies with the receiver's angle to the satellite, because that changes the distance through the ionosphere. The basic computation thus attempts to find the shortest directed line tangent to four oblate spherical shells centred on four satellites. Satellite navigation receivers reduce errors by using combinations of signals from multiple satellites and multiple correlators, and then using techniques such as Kalman filtering to combine the noisy, partial, and constantly changing data into a single estimate for position, time, and velocity.
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Chemistry Chapter
QMRJetties are added to bodies of water to regulate erosion, preserve navigation channels, and make harbors. Jetties are classified into four different types and have two main controlling variables: the type of delta and the size of the jetty.[24]
Type 1 jetty[edit]
The first classification is a type 1 jetty. This type of jetty is significantly longer than the surf zone width and the waves break at the shore end of the jetty. The effect of a Type 1 jetty is sediment accumulation in a wedge formation on the jetty. These waves are large and increase in size as they pass over the sediment wedge formation. An example of a Type 1 jetty is Mission Beach, San Diego, California. This 1000-meter jetty was installed in 1950 at the mouth of Mission Bay. The surf waves happen north of the jetty, are longer waves, and are powerful. The bathymetry of the sea bottom in Mission Bay has a wedge shape formation that causes the waves to refract as they become closer to the jetty.[24] The waves converge constructively after they refract and increase the sizes of the waves.
Type 2 jetty[edit]
A type 2 jetty occurs in an ebb tidal delta, a delta transitioning between high and low tide. This area has shallow water, refraction, and a distinctive seabed shapes that creates large wave heights.[24]
An example of a type 2 jetty is called "The Poles" in Atlantic Beach, Florida. Atlantic Beach is known to have flat waves, with exceptions during major storms. However, "The Poles" has larger than normal waves due to a 500-meter jetty that was installed on the south side of the St. Johns. This jetty was built to make a deep channel in the river. It formed a delta at "The Poles". This is special area because the jetty increases wave size for surfing, when comparing pre-conditions and post-conditions of the southern St. Johns River mouth area.[24]
The wave size at "The Poles" depends on the direction of the incoming water. When easterly waters (from 55°) interact with the jetty, they create waves larger than southern waters (from 100°). When southern waves (from 100°) move toward "The Poles", one of the waves breaks north of the southern jetty and the other breaks south of the jetty. This does not allow for merging to make larger waves. Easterly waves, from 55°, converge north of the jetty and unite to make bigger waves.[24]
Type 3 jetty[edit]
A type 3 jetty is in an ebb tidal area with an unchanging seabed that has naturally created waves. Examples of a Type 3 jetty occurs in “Southside” Tamarack, Carlsbad, California.[24]
Type 4 jetty[edit]
A type 4 jetty is one that no longer functions nor traps sediment. The waves are created from reefs in the surf zone. A type 4 jetty can be found in Tamarack, Carlsbad, California.[24]
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QMRA mnemonic device, the "four Cs" (color, cut, clarity and carats), has been introduced to help the consumer understand the factors used to grade a diamond.[8] With modification, these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weight depending upon whether they are applied to colored gemstones or to colorless diamonds. In diamonds, cut is the primary determinant of value, followed by clarity and color. Diamonds are meant to sparkle, to break down light into its constituent rainbow colors (dispersion), chop it up into bright little pieces (scintillation), and deliver it to the eye (brilliance). In its rough crystalline form, a diamond will do none of these things; it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, it is the purity and beauty of that color that is the primary determinant of quality.
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QMRThe hardness of diamond and its high dispersion of light – giving the diamond its characteristic "fire" – make it useful for industrial applications and desirable as jewelry. Diamonds are such a highly traded commodity that multiple organizations have been created for grading and certifying them based on the four Cs, which are color, cut, clarity, and carat. Other characteristics, such as presence or lack of fluorescence, also affect the desirability and thus the value of a diamond used for jewelry.The most familiar usage of diamonds today is as gemstones used for adornment—a usage which dates back into antiquity. The dispersion of white light into spectral colors is the primary gemological characteristic of gem diamonds. In the twentieth century, gemologists have developed methods of grading diamonds and other gemstones based on the characteristics most important to their value as a gem. Four characteristics known informally as the four Cs are now commonly used as the basic descriptors of diamonds: carat, cut, color, and clarity.
Most gem diamonds are traded on the wholesale market based on single values for each of the four Cs; for example knowing that a diamond is rated as 1.5 carats (300 mg), VS2 clarity, F color, excellent cut round brilliant, is enough to reasonably establish an expected price range. More detailed information from within each characteristic is used to determine actual market value for individual stones. Consumers who purchase individual diamonds are often advised to use the four Cs to pick the diamond that is "right" for them.
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QMrIn the Charaka Samhita of 300CE, ancient Indian medical writers saw the characteristics of the child as determined by four factors: 1) those from the mother’s reproductive material, (2) those from the father’s sperm, (3) those from the diet of the pregnant mother and (4) those accompanying the soul which enters into the foetus. Each of these four factors had four parts creating sixteen factors of which the karma of the parents and the soul determined which attributes predominated and thereby gave the child its characteristics.[2]
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QMRKnowledge and experience transcribing (from training or real report work) in the Basic Four work types: History and Physical Exam, Consultation, Operative Report, and Discharge Summary.
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QMRIn molecular cloning, a vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell, where it can be replicated and/or expressed. A vector containing foreign DNA is termed recombinant DNA. The four major types of vectors are plasmids, viral vectors, cosmids, and artificial chromosomes. Of these, the most commonly used vectors are plasmids. Common to all engineered vectors are an origin of replication, a multicloning site, and a selectable marker.
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QMRHering argued that yellow is not a "redgreen" but a unique hue. Colorimetrist Jan Koenderink, in a critique of Hering's system, considered it inconsistent not to apply the same argument to the other two subtractive primaries, cyan and magenta, and see them as unique hues as well, not a "greenblue" or a "redblue". He also pointed out the difficulty within a four color theory that the primaries would not be equally spaced in the color circle; and the problem that Hering does not account for the fact that cyan and magenta are brighter than green, blue and red, whereas this is elegantly explained within the CMYK-model. He concluded that Hering's scheme fitted common language better than color experience.[5]
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QMrThe Natural Step is a non-profit organization founded in Sweden in 1989 by scientist Karl-Henrik Robèrt. Following publication of the Brundtland Report in 1987, Robèrt developed The Natural Step framework, setting out the system conditions for the sustainability of human activities on Earth; Robèrt's four system conditions are derived from a scientific structured understanding of the socio-ecological system, including the laws of thermodynamics and social studies.Sustainability principles[edit]
The current FSSD's definition of sustainability includes four sustainability principles (first order scientific principles) that describe a sustainable society within the ecological system:
"In a sustainable society nature is not subject to systematically increasing concentrations of …
… substances extracted from the Earth's crust;
… substances produced as a byproduct of society ;
… degradation by physical means;
and in that society… people are not subject to conditions that systematically undermine their capacity to meet their needs."[3]
The 4 sustainability principles can be reworded, to simplify understanding and to apply to any society, organization or product. In short, to become a sustainable society we must… … eliminate our contribution to the progressive buildup of substances extracted from the Earth's crust; … eliminate our contribution to the progressive buildup of chemicals and compounds produced by society; … eliminate our contribution to the progressive physical degradation and destruction of nature and natural processes; and … eliminate our contribution to conditions that undermine people’s capacity to meet their basic human needs.[4]
The negative wording is often debated as the use of 'not' can have a negative emotional connotation. As in a game with game rules, it doesn't tell you everything you should do, they leave that up to the imagination of the players, they allow you to do anything as long as it is within all agreed rules of the game. The restrictions set by these 'rules of the game' stimulate creativity as they are applied in personal, professional or community planning and decision-making. On the success level organizations, institutes and individuals add their own (secondary) principles of success based on their specific context or needs.
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QMRThe Natural Four is the second album by the Oakland, California group The Natural Four, released in 1974 on Curtom Records.
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QMrFour-rotor Enigma[edit]
By late 1941 a change in German Navy fortunes in the Battle of the Atlantic, combined with intelligence reports, convinced Admiral Karl Dönitz that the Allies could read German Navy coded communications, and a fourth rotor with unknown wiring was added to German Navy Enigmas used for U-boat communications, producing the Triton system,[dubious – discuss] known at Bletchley Park as Shark. This was coupled with a thinner reflector design to make room for the extra rotor. The Triton was designed in such a way that it remained compatible with three-rotor machines when necessary. One of the extra 'fourth' rotors, the 'beta', was designed so that when it was paired with the thin 'B' reflector and rotor and ring were set to 'A', the pair acted as a standard three-rotor wide 'B' reflector. As before, the unknown wiring would prevent unauthorized reading of messages. Fortunately for the Allies, in December 1941, before the machine went into official service, a submarine accidentally sent a message with the fourth rotor in the wrong position. It then retransmitted the message with the rotor in the correct (three-rotor emulating) position. In February 1942 the change in the number of rotors used became official, and the Allies' ability to read German submarines' messages ceased until a snatch from a captured U-boat revealed not only the four-rotor machine's ability to emulate a three-rotor machine, but also that the fourth rotor did not move during a message. This along with the aforementioned mistake allowed the code breakers to eventually figure out the wiring of both the 'beta' and 'gamma' fourth rotors.
QMRThe Ben-Day dots printing process, named after illustrator and printer Benjamin Henry Day, Jr., (son of 19th Century publisher Benjamin Henry Day)[1][2][3][4] is a technique dating from 1879.[5] Depending on the effect, color and optical illusion needed, small colored dots are closely spaced, widely spaced or overlapping.[6] Magenta dots, for example, are widely spaced to create pink. Pulp comic books of the 1950s and 1960s used Ben-Day dots in the four process colors (cyan, magenta, yellow and black) to inexpensively create shading and secondary colors such as green, purple, orange and flesh tones.[7][8]
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QMRNew York Point is a braille-like system of tactile writing for the blind invented by William Bell Wait (1839–1916), a teacher in the New York Institute for the Education of the Blind. The system used one to four pairs of points set side by side, each containing one or two dots. (Letters of one through four pairs, each with two dots, would be ⟨:⟩ ⟨::⟩ ⟨:::⟩ ⟨::::⟩.) The most common letters are written with the fewest points, a strategy also employed by the competing American Braille.
Capital letters were cumbersome in New York Point, each being four dots wide, and so were not generally used. Likewise, the four-dot-wide hyphen and apostrophe were generally omitted. When capitals, hyphens, or apostrophes were used, they sometimes caused legibility problems, and a separate capital sign was never agreed upon. According to Helen Keller, this caused literacy problems among blind children, and was one of the chief arguments against New York Point and in favor of one of the braille alphabets.
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Qms Carbon and silicon- the miracle elements, both have four valence electrons and are thus shaped as quadrants. Carbon forms the key component for all known life on Earth. Complex molecules are made up of carbon bonded with other elements, especially oxygen, hydrogen and nitrogen, and carbon is able to bond with all of these because of its four valence electrons. Carbon is abundant on earth. It is also lightweight and relatively small in size, making it easier for enzymes to manipulate carbon molecules.[citation needed] It is often[how often?] assumed in astrobiology that if life exists somewhere else in the universe, it will also be carbon based.[1][2] Critics refer to this assumption as carbon chauvinism.[citation needed]
Carbon is shaped lie a quadrant."What we normally think of as 'life' is based on chains of carbon atoms, with a few other atoms, such as nitrogen or phosphorus", per Stephen Hawking in a 2008 lecture, "carbon [...] has the richest chemistry." [3] The most important characteristics of carbon as a basis for the chemistry of life are, that it has four valence bonds, that the energy required to make or break a bond is at an appropriate level for building molecules, which are stable and reactive.[citation needed] Because carbon atoms bond readily to other carbon atoms allows for the building of arbitrarily long complex molecules and polymers.[citation needed]
Other candidates[edit]
There are not many other elements which even appear to be promising candidates for supporting life, for example, processes such as metabolism; the most frequently suggested alternative is silicon.[4] It is in the same group in the Periodic Table of elements, has four valence bonds, bonds to itself, generally in the form of crystal lattices rather than long chains.[citation needed] Silicon compounds do not support the ability to readily re-combine in different permutations in a manner that would plausibly support lifelike processes.[citation needed]
The most notable groups of chemicals used in the processes of living organisms include:
Proteins, which are the building blocks from which the structures of living organisms are constructed (this includes almost all enzymes, which catalyse organic chemical reactions)
Nucleic acids, which carry genetic information
Carbohydrates, which store energy in a form that can be used by living cells
Lipids, which also store energy, but in a more concentrated form, and which may be stored for extended periods in the bodies of animals.
Silicon has been a theme of non-carbon-based-life since it also has 4 bonding sites and is just below carbon on the periodic table of the elements. This means silicon is very similar to carbon in its chemical characteristics. In cinematic and literary science fiction, when man-made machines cross from nonliving to living, this new form would be an example of non-carbon-based life. Since the advent of the microprocessor in the late 1960s, these machines are often classed as "silicon-based life". Another example of "silicon-based life" is the episode "The Devil in the Dark" from Star Trek: The Original Series, where a living rock creature's biochemistry is based on silicon.
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QMrSnaps are a brand of classic chewy candy, manufactured by American Licorice Company. They have hollow centers and are colored four colors white, orange, green, and pink.
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QMRThe basic ingredients of jelly beans are four -sugar, corn syrup, and pectin/starch
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QMR
16 is the squares of the quadrant model
Dum Dums are sphere-shaped lollipops named by I. C. Bahr, a sales manager at the Akron Candy Company in Bellevue, Ohio, in 1924. In 1953, the Dum Dum Pop was purchased by the Spangler Candy Company and moved manufacturing to Bryan, Ohio.[1]
Flavors[edit]
Dum Dums are made in sixteen flavors with new flavors rotating into the mix every so often.[2] The Mystery Flavor is a result of the end of one batch mixing with the next batch, rather than stopping production to clean machines in between flavors.[3]
Current Flavors
Blackberry (2016-Present)
Blue Raspberry (1995–Present)
Cherry (original flavor, 1953–Present)
Coconut (2008–2010), (2016-Present)
Grape (original flavor, 1953–Present)
Lemon Lime (2015–Present)
Maple Syrup (2016-Present)
Mystery (2001–Present)
Orange (original flavor, 1953–2000, 2011–Present)
Orange Cream (2000–2002, 2016-Present)
Peach-Mango (2013–Present)
Raspberry Lemonade (2013-2015), (2016-Present)
Sour Apple (1991–2000, 2001–Present)
Strawberry (1954–Present)
Tangerine (2008–2011), (2016-Present)
Watermelon (1982–Present)
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QMRThe original line of Sour Patch Kids came in four flavors, Lime (green), Lemon (yellow), Orange (orange), and Raspberry (red). Later Blue and other flavors were added
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QMR
Name Manufacturer Image Description
Prince Polo Kraft Jacobs Suchard Prince-Polo-Dark-Split.jpg A Polish chocolate bar that was introduced in 1955, during the early years of the Polish People's Republic, by Olza S.A. in Cieszyn. It is a chocolate-covered wafer, with four layers of wafer joined by three layers of chocolate-flavored filling; it was easily identifiable by its metallic gold-colored wrapper.
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Biology Chapter
QMRPurkinje images are reflections of objects from the structure of the eye. They are also known as Purkinje reflexes and as Purkinje-Sanson images. At least four Purkinje images are usually visible. The first Purkinje image (P1) is the reflection from the outer surface of the cornea. The second Purkinje image (P2) is the reflection from the inner surface of the cornea. The third Purkinje image (P3) is the reflection from the outer (anterior) surface of the lens. The fourth Purkinje image (P4) is the reflection from the inner (posterior) surface of the lens. Unlike the others, P4 is an inverted image.
Purkinje-Sanson images are named after Czech anatomist Jan Evangelista Purkyně (1787–1869) and after French physician Louis Joseph Sanson (1790–1841).
The third and fourth Purkinje images can be visible from within the eye itself. Light reflected away from the surfaces of the lens can in turn reflect back into the eye from the rear surface of the cornea. These images are, therefore, entoptic phenomena.
The first and fourth Purkinje images are used by some eye trackers, devices to measure the position of an eye. The cornea reflection (P1 image) used in this measurement is generally known as glint.[2]
The brightness of the Purkinje images can be determined using Fresnel's equation: \text{Intensity (brightness)} = (n'-n)^2/(n'+n)^2, where n and n' are the refractive indices before and after the reflecting surface. Purkinje image P1 is the brightest of the four then, P3 and P4 (P3 and P4 have about the same brightness), then P2. The Purkinje images can be used to assess the curvatures and separations of the surfaces in the eye.
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QMR
The fourth is always different.
The Three Sisters are the three main agricultural crops of various Native American groups in North America: winter squash, maize (corn), and climbing beans (typically tepary beans or common beans). One of the major Native American tribes that used these "Three Sisters" to trade with others was the Iroquois Confederacy.
Native Americans throughout North America are known for growing variations of Three Sisters gardens.[7] The milpas of Mesoamerica are farms or gardens that employ companion planting on a larger scale.[8] The Anasazi are known for adopting this garden design in a drier environment. The Tewa and other Southwestern United States tribes often included a "fourth sister" known as "Rocky Mountain bee plant" (Cleome serrulata), which attracts bees to help pollinate the beans and squash.[9]
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QMrA four-field rotation was pioneered by farmers, namely in the region Waasland in the early 16th century and popularised by the British agriculturist Charles Townshend in the 18th century. The system (wheat, turnips, barley and clover), opened up a fodder crop and grazing crop allowing livestock to be bred year-round. The four-field crop rotation was a key development in the British Agricultural Revolution.
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QMrThe Omnivore's Dilemma: A Natural History of Four Meals is a nonfiction book by Michael Pollan published in 2006. In the book, Pollan asks the seemingly straightforward question of what we should have for dinner. As omnivores, the most unselective eaters, humans (as well as other omnivores) are faced with a wide variety of food choices, resulting in a dilemma. Pollan suggests that, prior to modern food preservation and transportation technologies, this particular dilemma was resolved primarily through cultural influences. These technologies have recreated the dilemma, by making available foods that were previously seasonal or regional. The relationship between food and society, once moderated by culture, now finds itself confused. To learn more about those choices, Pollan follows each of the food chains that sustain us; industrial food, organic food, and food we forage ourselves; from the source to a final meal, and in the process writes a critique of the American way of eating.
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QMRKaempferia galanga, commonly known as kencur, aromatic ginger, sand ginger, cutcherry or resurrection lily, is a monocotyledonous plant in the ginger family, and one of four plants called galangal. It is found primarily in open areas in Indonesia, southern China, Taiwan, Cambodia and India, but is also widely cultivated throughout Southeast Asia.
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QMRThe Four Cs of 21st century learning, also known as the Four Cs or 4 Cs, are four skills that have been identified by the USA-based Partnership for 21st Century Skills (P21) as the most important skills required for 21st century education: critical thinking, communication, collaboration, and creativity.[1][2][3][4][5]
These 21st century skills have been identified and supported by national educational and political leaders in the United States, including President Obama.[6] In January 2016 members of the US House of Representatives created a bipartisan Congressional 21st Century Skills Caucus.[7] The Four Cs have been adopted and implemented into the curricula of schools, school districts, and professional development programs.[8]
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QMRA rotator cuff tear is a tear of one or more of the tendons of the four rotator cuff muscles of the shoulder. A rotator cuff 'injury' can include any type of irritation or overuse of those muscles or tendons,[1] and is among the most common conditions affecting the shoulder.[2]
The tendons of the rotator cuff, not the muscles, are most commonly involved, and of the four, the supraspinatus is most frequently affected, as it passes below the acromion. Such a tear usually occurs at its point of insertion onto the humeral head at the greater tubercle.[3]
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QMRTears are classified into four categories:[3][4]
First-degree tear: laceration is limited to the fourchette and superficial perineal skin or vaginal mucosa
Second-degree tear: laceration extends beyond fourchette, perineal skin and vaginal mucosa to perineal muscles and fascia, but not the anal sphincter
Third-degree tear: fourchette, perineal skin, vaginal mucosa, muscles, and anal sphincter are torn; third-degree tears may be further subdivided into three subcategories:[5]
3a: partial tear of the external anal sphincter involving less than 50% thickness
3b: greater than 50% tear of the external anal sphincter
3c: internal sphincter is torn
Fourth-degree tear: fourchette, perineal skin, vaginal mucosa, muscles, anal sphincter, and rectal mucosa are torn
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QMRIn most vertebrates, digestion is a four-stage process involving the main structures of the digestive tract, starting with ingestion, placing food into the mouth, and concluding with the excretion of undigested material through the anus. From the mouth, the food moves to the stomach, where as bolus it is broken down chemically. It then moves to the intestine, where the process of breaking the food down into simple molecules continues and the results are absorbed as nutrients into the circulatory and lymphatic system.
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QMRCicada 3301 is a name given to an enigmatic organization that on four occasions has posted a set of complex puzzles and alternate reality games to recruit codebreakers from the public.[1] The first internet puzzle started on January 4, 2012, and ran for approximately one month. A second round began one year later on January 4, 2013, and a third round is ongoing following confirmation of a fresh clue posted on Twitter on January 4, 2014.[2][3] The stated intent was to recruit "intelligent individuals" by presenting a series of puzzles which were to be solved, each in order, to find the next. No new puzzles were published on January 4, 2015. However, a new puzzle was posted on Twitter on January 5, 2016.[4] The puzzles focused heavily on data security, cryptography, and steganography.[1][5][6][7][8]
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QMRA pyramid puzzle is a mechanical puzzle (assembly puzzle) consisting of two or more component pieces which fit together to create a pyramid.
History[edit]
Unknown origin. Children of American pioneers played with simple toys such as these.
A four-piece wooden pyramid puzzle.
Solutions[edit]
Two-piece pyramid puzzles: A regular pyramid is not possible in this case. Instead, we can only form a 4 faced tetrahedron pyramid.
To do this, make the square faces face each other and twist one upright to complete the four faced tetrahedronic pyramid.
Four-piece pyramid puzzles: Join the four identical pieces in pairs so that the smallest triangular faces meet. Turn the squares to face each other and bring them together. This will leave a square face on the two resulting pieces. With the square sides of the blocks facing each other, twist one piece upright to complete the pyramid.
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QMRThe T puzzle is a tiling puzzle consisting of four polygonal shapes which can be put together to form a capital T. The four pieces are usually one isosceles right triangle, two right trapezoids and an irregular shaped pentagon. Despite its apparent simplicity, it is a surprisingly hard puzzle of which the crux is the positioning of the irregular shaped piece. The earliest T puzzles date from around 1900 and were distributed as promotional giveaways. From the 1920s wooden specimen were produced and made available commercially. At 2015, most T puzzles come with a leaflet with additional figures to be constructed. Which shapes can be formed depends on the relative proportions of the different pieces.
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QMRThe prisoners and hats puzzle is an induction puzzle (a kind of logic puzzle) that involves reasoning about the actions of other people, drawing in aspects of Game theory sometimes called the hierarchy of beliefs. There are many variations, but the central theme remains the same. It is not to be confused with the similar Hat Puzzle.
According to the story, four prisoners are arrested for a crime, but the jail is full and the jailor has nowhere to put them. He eventually comes up with the solution of giving them a puzzle so if they succeed they can go free but if they fail they are executed.
[1]
The jailor puts three of the men sitting in a line. The fourth man is put behind a screen (or in a separate room). He gives all four men party hats. The jailor explains that there are two black hats, and two white hats; that each prisoner is wearing one of the hats; and that each of the prisoners only see the hats in front of him but not on himself or behind him. The fourth man behind the screen can't see or be seen by any other prisoner. No communication among the prisoners is allowed.
If any prisoner can figure out and say to the jailor what color hat he has on his head with 100% certainty (without guessing) all four prisoners go free. If any prisoner suggests an incorrect answer, all four prisoners are executed. The puzzle is to find how the prisoners can escape, regardless of how the jailer distributes the hats.
The solution[edit]
For the sake of explanation let's label the prisoners in line order B, C and D. Thus C can see B (and B's hat color) and D can see B and C.
The prisoners know that there are only two hats of each color. So if D observes that B and C have hats of the same color, D would deduce that his own hat is the opposite color. However, if B and C have hats of different colors, then D can say nothing. The key is that prisoner C, after allowing an appropriate interval, and knowing what D would do, can deduce that if D says nothing the hats on B and C must be different. Being able to see B's hat he can deduce his own hat color.
In common with many puzzles of this type, the solution relies on the assumption that all participants are totally rational and are intelligent enough to make the appropriate deductions.
After solving this puzzle, some insight into the nature of communication can be gained by pondering whether the meaningful silence of prisoner D violates the "No communication" rule (given that communication is usually defined as the "transfer of information").
Variants[edit]
Four-Hat Variant[edit]
In a variant of this puzzle, the prisoners know that there are 3 hats of one color and only 1 hat of another, and the 3 prisoners can see each other i.e. A sees B & C, B sees A & C, and C sees A & B. (D again not to be seen and only there to wear the last hat.)
The solution[edit]
There are two cases: in the trivial case, one of the three prisoners wears the single off-color hat. Each of the other two prisoners can see that one prisoner is wearing the off-color hat. In the non-trivial case, the three prisoners wear hats of the same color, while D wears the off-color hat. After a while, all three prisoners should be able to deduce that, because neither of the others was able to state the color of his own hat, D must wear the off-color hat.
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QMrThe four glasses puzzle, also known as the blind bartender's problem,[1] is a logic puzzle first publicised by Martin Gardner in his "Mathematical Games" column in the February 1979 edition of Scientific American.[2]
Four glasses or tumblers are placed on the corners of a square Lazy Susan. Some of the glasses are upright (up) and some upside-down (down). A blindfolded person is seated next to the Lazy Susan and is required to re-arrange the glasses so that they are all up or all down, either arrangement being acceptable, which will be signalled by the ringing of a bell. The glasses may be re-arranged in turns subject to the following rules. Any two glasses may be inspected in one turn and after feeling their orientation the person may reverse the orientation of either, neither or both glasses. After each turn the Lazy Susan is rotated through a random angle. The puzzle is to devise an algorithm which allows the blindfolded person to ensure that all glasses have the same orientation (either up or down) in a finite number of turns. The algorithm must be non-stochastic i.e. it must not depend on luck.[3]
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QMrCross for the Four Day Marches (Dutch: Vierdaagskruis): awarded to participants who successfully completed the Four Days Marches according to regulations. The medal is an official Dutch decoration that can be worn on a Dutch military uniform. It is fully named "Cross for demonstrated marching skill", as defined by Royal Decree on 6 October 1909. The walker receives a specific medal depending on the number of times he or she successfully finished the event. The Four Day Marches Cross can be awarded in bronze, silver or gold, which may have a crown above the cross, together with enamelled arms. The ribbon bears numbers and/or a laurel wreath and number or single or double pearl necklace and number, all depending on the number of times the participant has completed the marches.
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QMRThe GOR method analyzes sequences to predict alpha helix, beta sheet, turn, or random coil secondary structure at each position based on 17-amino-acid sequence windows. The original description of the method included four scoring matrices of size 17×20, where the columns correspond to the log-odds score, which reflects the probability of finding a given amino acid at each position in the 17-residue sequence. The four matrices reflect the probabilities of the central, ninth amino acid being in a helical, sheet, turn, or coil conformation. In subsequent revisions to the method, the turn matrix was eliminated due to the high variability of sequences in turn regions (particularly over such a large window). The method was considered as best requiring at least four contiguous residues to score as alpha helices to classify the region as helical, and at least two contiguous residues for a beta sheet.[3]
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QMRJan Swammerdam (February 12, 1637 – February 17, 1680) was a Dutch biologist and microscopist. His work on insects demonstrated that the various four phases during the life of an insect—egg, larva, pupa, and adult—are different forms of the same animal. As part of his anatomical research, he carried out experiments on muscle contraction. In 1658, he was the first to observe and describe red blood cells. He was one of the first people to use the microscope in dissections, and his techniques remained useful for hundreds of years.
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QMrPlants use four kinds of photoreceptors:[1] phytochrome, cryptochrome, a UV-B photoreceptor, and protochlorophyllide a. The first two of these, phytochrome and cryptochrome, are photoreceptor proteins, complex molecular structures formed by joining a protein with a light-sensitive pigment. Cryptochrome is also known as the UV-A photoreceptor, because it absorbs ultraviolet light in the long wave "A" region. The UV-B receptor is one or more compounds not yet identified with certainty, though some evidence suggests carotene or riboflavin as candidates.[4] Protochlorophyllide a, as its name suggests, is a chemical precursor of chlorophyll.
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QMrIn the latter 19th century French physical anthropologists, led by Paul Broca (1824–1880), focused on craniometry while the German tradition, led by Rudolf Virchow (1821–1902), emphasized the influence of environment and disease upon the human body. American thought has evolved during the “four-field approach”, skeletons, artifacts, language and culture and many (ways of life), based upon study's on the remains of the North American hominin clade.
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QMRPuducherry, formerly known as Pondicherry (/ˌpɒndᵻˈtʃɛri/; literally New Town in Tamil),[4] is a Union Territory of India. It was formed out of four exclaves of former French India, namely Puducherry, Karaikal, Yanam and Mahe. It is named after the largest district Puducherry. Historically known as Pondicherry (Pāṇṭiccēri), the territory changed its official name to Puducherry (Putuccēri) on 20 September 2006.[5]
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QMRHistorically, four models have been proposed for the formation and persistence of gene clusters.
Gene duplication and divergence[edit]
This model has been generally accepted since the mid-1970s. It postulates that gene clusters were formed as a result of gene duplication and divergence.[2] These gene clusters include the Hox gene cluster, the human β-globin gene cluster, and four clustered human growth hormone (hGH)/chorionic somaomammotropin genes.[3]
Conserved gene clusters, such as Hox and the human β-globin gene cluster, may be formed as a result of the process of gene duplication and divergence. A gene is duplicated during cell division, so that its descendants have two end-to-end copies of the gene where it had one copy, initially coding for the same protein or otherwise having the same function. In the course of subsequent evolution, they diverge, so that the products they code for have different but related functions, with the genes still being adjacent on the chromosome.[4] Ohno theorized that the origin of new genes during evolution was dependent on gene duplication. If only a single copy of a gene existed in the genome of a species, the proteins transcribed from this gene would be essential to their survival. Because there was only a single copy of the gene, they could not undergo mutations which would potentially result in new genes; however, gene duplication allows essential genes to undergo mutations in the duplicated copy, which would ultimately give rise to new genes over the course of evolution.[5] Mutations in the duplicated copy were tolerated because the original copy contained genetic information for the essential gene's function. Species who have gene clusters have a selective evolutionary advantage because natural selection must keep the genes together.[1][6] Over a short span of time, the new genetic information exhibited by the duplicated copy of the essential gene would not serve a practical advantage; however, over a long, evolutionary time period, the genetic information in the duplicated copy may undergo additional and drastic mutations in which the proteins of the duplicated gene served a different role than those of the original essential gene.[5] Over the long, evolutionary time period, the two similar genes would diverge so the proteins of each gene were unique in their functions. Hox gene clusters, ranging in various sizes, are found among several phyla.
Hox cluster[edit]
When gene duplication occurs to produce a gene cluster, one or multiple genes may be duplicated at once. In the case of the Hox gene, a shared ancestral ProtoHox cluster was duplicated, resulting in genetic clusters in the Hox gene as well as the ParaHox gene, an evolutionary sister complex of the Hox gene.[7] It is unknown the exact number of genes contained in the duplicated Protohox cluster; however, models exist suggesting that the duplicated Protohox cluster originally contained four, three, or two genes.[8]
In the case where a gene cluster is duplicated, some genes may be lost. Loss of genes is dependent of the number of genes originating in the gene cluster. In the four gene model, the ProtoHox cluster contained four genes which resulted in two twin clusters: the Hox cluster and the ParaHox cluster.[7] As its name indicates, the two gene model gave rise to the Hox cluster and the ParaHox cluster as a result of the ProtoHox cluster which contained only two genes. The three gene model was originally proposed in conjunction with the four gene model;[8] however, rather than the Hox cluster and the ParaHox cluster resulting from a cluster containing three genes, the Hox cluster and ParaHox cluster were as a result of single gene tandem duplication, identical genes found adjacent on the same chromosome.[7] This was independent of duplication of the ancestral ProtoHox cluster.
Intrachromosomal duplication is the duplication of genes within the same chromosome over the course of evolution (a-1). Mutations may occur in the duplicated copy, such as observed with the substitution of Guanine with Adenine (a-2). Alignment of DNA sequences exhibits homology between the two chromosomes (a-3). All segments were duplicated from the same ancestral DNA sequence as observed by the comparisons in b(i-iii).
Cis vs. trans duplication[edit]
Gene duplication may occur via cis-duplication or trans duplication. Cis-duplication, or intrachromosomal duplication, entails the duplication of genes within the same chromosome whereas trans duplication, or interchromosomal duplication, consists of duplicating genes on neighboring but separate chromosomes.[7] The formations of the Hox cluster and of the ParaHox cluster were results of intrachromosomal duplication, although they were initially thought to be interchromosomal.[8]
Fisher Model[edit]
The Fisher Model was proposed in 1930 by Ronald Fisher. Under the Fisher Model, gene clusters are a result of two alleles working well with one another. In other words, gene clusters may exhibit co-adaptation.[3] The Fisher Model was considered unlikely and later dismissed as an explanation for gene cluster formation.[2][3]
Coregulation Model[edit]
Under the coregulation model, genes are organized into clusters, each consisting of a single promoter and a cluster of coding sequences, which are therefore co-regulated, showing coordinated gene expression.[3] Coordinated gene expression was once considered to be the most common mechanism driving the formation of gene clusters.[1] However coregulation and thus coordinated gene expression cannot drive the formation of gene clusters.[3]
Molarity Model[edit]
The Molarity Model considers the constraints of cell size. Transcribing and translating genes together is beneficial to the cell.[9] thus the formation of clustered genes generates a high local concentration of cytoplasmic protein products. Spatial segregation of protein products has been observed in bacteria; however, the Molarity Model does not consider co-transcription or distribution of genes found within an operon.[2]
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QMR
The process of regulating emotions is complex, and involves four stages:[2]
internal feeling states (i.e. the subjective experience of emotion)
emotion-related cognitions (e.g. thought reactions to a situation)
emotion-related physiological processes (e.g. heart rate, hormonal, or other physiological reactions)
emotion-related behavior (e.g. actions or facial expressions related to emotion).
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QMrFour Types of Noise Regulation[edit]
[24] Fixed sound sources must be treated differently that moving sources. In the former case, the listener is normally while defined while for moving sources it is not. Historically, regulations were enforced by the subjective judgment on an enforcing officer. With the advent of sound measuring equipment, the judgment can be based on measured sound levels. Most comprehensive noise ordinances contain four types of provisions.
Subjective Emission These regulations allow an official to decide if the output of a sound source is acceptable without recourse to sound measurements and without regard to the presence of a specific listener. Regulations with plainly audible terms on public property as a criterion are examples.
Subjective Immission These regulations allow an official to decide if the sound received by a listener is acceptable without recourse to sound measurements and without regard for the specific sound power generated by the source.. Regulations with plainly audible or noise disturbance terms on private property as a criterion are examples.
Objective Emission These regulations require an official to measure the output of a sound source to determine whether it is acceptable without regard to the presence of a specific listener. Regulations with specific maximum sound output levels for motor vehicles are examples.
Objective Immission These regulations require an official to measure the sound received by a listener to determine whether it is acceptable without regard to the specific sound power generated by the source. Regulations with maximum allowable sound levels on property lines are examples
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QMRHeme (from the Greek "Αίμα" which means blood) is a cofactor consisting of an Fe2+ (ferrous) ion contained in the centre of a large heterocyclic organic ring called a porphyrin, made up of four pyrrolic groups joined together by methine bridges. Not all porphyrins contain iron, but a substantial fraction of porphyrin-containing metalloproteins have heme as their prosthetic group; these are known as hemoproteins. Hemes are most commonly recognized as components of hemoglobin, the red pigment in blood, but are also found in a number of other biologically important hemoproteins such as myoglobin, cytochrome, catalase, heme peroxidase, and endothelial nitric oxide synthase.
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QMRThere are four kinds of reversible enzyme inhibitors. They are classified according to the effect of varying the concentration of the enzyme's substrate on the inhibitor.[2]
Types of inhibition. This classification was introduced by W.W. Cleland.[3]
In competitive inhibition, the substrate and inhibitor cannot bind to the enzyme at the same time, as shown in the figure on the right. This usually results from the inhibitor having an affinity for the active site of an enzyme where the substrate also binds; the substrate and inhibitor compete for access to the enzyme's active site. This type of inhibition can be overcome by sufficiently high concentrations of substrate (Vmax remains constant), i.e., by out-competing the inhibitor. However, the apparent Km will increase as it takes a higher concentration of the substrate to reach the Km point, or half the Vmax. Competitive inhibitors are often similar in structure to the real substrate (see examples below).
In uncompetitive inhibition, the inhibitor binds only to the substrate-enzyme complex, it should not be confused with non-competitive inhibitors. This type of inhibition causes Vmax to decrease (maximum velocity decreases as a result of removing activated complex) and Km to decrease (due to better binding efficiency as a result of Le Chatelier's principle and the effective elimination of the ES complex thus decreasing the Km which indicates a higher binding affinity).
In non-competitive inhibition, the binding of the inhibitor to the enzyme reduces its activity but does not affect the binding of substrate. As a result, the extent of inhibition depends only on the concentration of the inhibitor. Vmax will decrease due to the inability for the reaction to proceed as efficiently, but Km will remain the same as the actual binding of the substrate, by definition, will still function properly.
In mixed inhibition, the inhibitor can bind to the enzyme at the same time as the enzyme's substrate. However, the binding of the inhibitor affects the binding of the substrate, and vice versa. This type of inhibition can be reduced, but not overcome by increasing concentrations of substrate. Although it is possible for mixed-type inhibitors to bind in the active site, this type of inhibition generally results from an allosteric effect where the inhibitor binds to a different site on an enzyme. Inhibitor binding to this allosteric site changes the conformation (i.e., tertiary structure or three-dimensional shape) of the enzyme so that the affinity of the substrate for the active site is reduced.
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Crystallographic studies of cytochrome c oxidase show an unusual post-translational modification, linking C6 of Tyr(244) and the ε-N of His(240) (bovine enzyme numbering). It plays a vital role in enabling the cytochrome a3- CuB binuclear center to accept four electrons in reducing molecular oxygen to water. The mechanism of reduction was formerly thought to involve a peroxide intermediate, which was believed to lead to superoxide production. However, the currently accepted mechanism involves a rapid four-electron reduction involving immediate oxygen-oxygen bond cleavage, avoiding any intermediate likely to form superoxide.[5]
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QMRThe enzyme cytochrome c oxidase, or Complex IV (EC 1.9.3.1), is a large transmembrane protein complex found in bacteria and the mitochondrion of eukaryotes.
It is the last enzyme in the respiratory electron transport chain of mitochondria or bacteria located in the mitochondrial or bacterial membrane. It receives an electron from each of four cytochrome c molecules, and transfers them to one oxygen molecule, converting molecular oxygen to two molecules of water. In the process, it binds four protons from the inner aqueous phase to make water, and in addition translocates four protons across the membrane, helping to establish a transmembrane difference of proton electrochemical potential that the ATP synthase then uses to synthesize ATP.[1][2]
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QMRProteases were first grouped into 84 families according to their evolutionary relationship in 1993, and classified under four catalytic types: serine, cysteine, aspartic, and metallo proteases.[2] The threonine and glutamic-acid proteases were not described until 1995 and 2004 respectively. The mechanism used to cleave a peptide bond involves making an amino acid residue that has the cysteine and threonine (proteases) or a water molecule (aspartic acid, metallo- and glutamic acid proteases) nucleophilic so that it can attack the peptide carboxyl group. One way to make a nucleophile is by a catalytic triad, where a histidine residue is used to activate serine, cysteine, or threonine as a nucleophile. This is not an evolutionary grouping, however, as the nucleophile types have evolved convergently in different superfamilies, and some superfamilies show divergent evolution to multiple different nucleophiles.
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QMRNaturally occurring restriction endonucleases are categorized into four groups (Types I, II III, and IV) based on their composition and enzyme cofactor requirements, the nature of their target sequence, and the position of their DNA cleavage site relative to the target sequence.[30][31][32] All types of enzymes recognize specific short DNA sequences and carry out the endonucleolytic cleavage ofDNA to give specific fragments with terminal 5'-phosphates. They differ in their recognition sequence, subunit composition, cleavage position, and cofactor requirements,[33][34] as summarised below:
Type I enzymes (EC 3.1.21.3) cleave at sites remote from recognition site; require both ATP and S-adenosyl-L-methionine to function; multifunctional protein with both restriction and methylase (EC 2.1.1.72) activities.
Type II enzymes (EC 3.1.21.4) cleave within or at short specific distances from recognition site; most require magnesium; single function (restriction) enzymes independent of methylase.
Type III enzymes (EC 3.1.21.5) cleave at sites a short distance from recognition site; require ATP (but do not hydrolyse it); S-adenosyl-L-methionine stimulates reaction but is not required; exist as part of a complex with a modification methylase (EC 2.1.1.72).
Type IV enzymes target modified DNA, e.g. methylated, hydroxymethylated and glucosyl-hydroxymethylated DNA
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QMRAll enzyme assays measure either the consumption of substrate or production of product over time. A large number of different methods of measuring the concentrations of substrates and products exist and many enzymes can be assayed in several different ways. Biochemists usually study enzyme-catalysed reactions using four types of experiments:[3]
Initial rate experiments. When an enzyme is mixed with a large excess of the substrate, the enzyme-substrate intermediate builds up in a fast initial transient. Then the reaction achieves a steady-state kinetics in which enzyme substrate intermediates remains approximately constant over time and the reaction rate changes relatively slowly. Rates are measured for a short period after the attainment of the quasi-steady state, typically by monitoring the accumulation of product with time. Because the measurements are carried out for a very short period and because of the large excess of substrate, the approximation that the amount of free substrate is approximately equal to the amount of the initial substrate can be made. The initial rate experiment is the simplest to perform and analyze, being relatively free from complications such as back-reaction and enzyme degradation. It is therefore by far the most commonly used type of experiment in enzyme kinetics.
Progress curve experiments. In these experiments, the kinetic parameters are determined from expressions for the species concentrations as a function of time. The concentration of the substrate or product is recorded in time after the initial fast transient and for a sufficiently long period to allow the reaction to approach equilibrium. Progress curve experiments were widely used in the early period of enzyme kinetics, but are less common now.
Transient kinetics experiments. In these experiments, reaction behaviour is tracked during the initial fast transient as the intermediate reaches the steady-state kinetics period. These experiments are more difficult to perform than either of the above two classes because they require specialist techniques (such as flash photolysis of caged compounds) or rapid mixing (such as stopped-flow, quenched flow or continuous flow).
Relaxation experiments. In these experiments, an equilibrium mixture of enzyme, substrate and product is perturbed, for instance by a temperature, pressure or pH jump, and the return to equilibrium is monitored. The analysis of these experiments requires consideration of the fully reversible reaction. Moreover, relaxation experiments are relatively insensitive to mechanistic details and are thus not typically used for mechanism identification, although they can be under appropriate conditions.
Enzyme assays can be split into two groups according to their sampling method: continuous assays, where the assay gives a continuous reading of activity, and discontinuous assays, where samples are taken, the reaction stopped and then the concentration of substrates/products determined.
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QMRAristotle, the most influential of the Greek philosophers in Europe in the Middle Ages, was a student of Plato and is also the earliest natural historian whose work has been preserved in any real detail. His writings on biology resulted from his research into natural history on and around the island of Lesbos, and have survived in the form of four books, usually known by their Latin names, De anima (On the Soul), Historia animalium (History of Animals), De generatione animalium (Generation of Animals), and De partibus animalium (On the Parts of Animals). Aristotle's works contain some remarkably astute observations and interpretations—along with sundry myths and mistakes—reflecting the uneven state of knowledge during his time.[10] However, for Charles Singer, "Nothing is more remarkable than [Aristotle's] efforts to [exhibit] the relationships of living things as a scala naturae."[10] This scala naturae, described in Historia animalium, classified organisms in relation to a hierarchical "Ladder of Life" or "great chain of being," placing them according to their complexity of structure and function, with organisms that showed greater vitality and ability to move described as "higher organisms."[8] Aristotle believed that features of living organisms showed clearly that they must have had what he called a final cause, that is to say that they had been designed for a purpose.[11] He explicitly rejected the view of Empedocles that living creatures might have originated by chance.[12]
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QMRThroughout his life Gessner was interested in natural history, and collected specimens and descriptions of wildlife through travel and extensive correspondence with other friends and scholars. His approach to research consisted of four main components: observation, dissection, travel to distant lands, and accurate description. This rising observational approach was new to Renaissance scholars because people usually relied completely upon Classical writers for their research.[4] He died of the plague, the year after his ennoblement on December 13, 1565.
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QMRIn the History of Animals, Aristotle sets out to investigate the existing facts (Greek "hoti", what), prior to establishing their causes (Greek "dioti", why).[1][2] The book is thus a defence of his method of investigating zoology. Aristotle investigates four types of differences between animals: differences in particular body parts (Books I to IV); differences in ways of life and types of activity (Books V, VI, VII and IX); and differences in specific characters (Book VIII).[1]
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E. coli GlgX is structurally similar to the protein isoamylase. The monomeric protein contains a central domain in which eight parallel beta-strands are surrounded by eight parallel alpha strands. Notable within this structure is a groove 26 angstroms long and 9 angstroms wide, containing aromatic residues that are thought to stabilize a four-glucose branch before cleavage.[2]
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QMRTogether with phosphorylase, glycogen debranching enzymes function in glycogen breakdown and glucose mobilization. When phosphorylase has digested a glycogen branch down to four glucose residues, it will not remove further residues. Glycogen debranching enzymes assist phosphorylase, the primary enzyme involved in glycogen breakdown, mobilize glycogen stores. Phosphorylase can only cleave α-1,4- glycosidic bond between adjacent glucose molecules in glycogen but branches exist as α-1,6 linkages. When phosphorylase reaches four residues from a branching point it stops cleaving; because 1 in 10 residues is branched, cleavage by phosphorylase alone would not be sufficient in mobilizing glycogen stores.[5][6] Before phosphorylase can resume catabolism, debranching enzymes perform two functions:
4-α-D-glucanotransferase (EC 2.4.1.25), or glucosyltransferase, transfers three glucose residues from the four-residue glycogen branch to a nearby branch. This exposes a single glucose residue joined to the glucose chain through an α -1,6 glycosidic linkage[5]
Amylo-α-1,6-glucosidase (EC 3.2.1.33), or glucosidase, cleaves the remaining alpha-1,6 linkage, producing glucose and a linear chain of glycogen.[5] The mechanism by which the glucosidase cleaves the α -1,6-linkage is not fully known because the amino acids in the active site have not yet been identified. It is thought to proceed through a two step acid base assistance type mechanism, with an oxocarbenium ion intermediate, and retention of configuration in glucose.[7] This is a common method through which to cleave bonds, with an acid below the site of hydrolysis to lend a proton and a base above to deprotinate a water which can then act as a nucleophile. These acids and bases are amino acid side chains in the active site of the enzyme. A scheme for the mechanism is shown in the figure below.[8]
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QMrTinbergen's four questions, named after Nikolaas Tinbergen, are complementary categories of explanations for behaviour. It suggests that an integrative understanding of behaviour must include both a proximate and ultimate (functional) analysis of behaviour, as well as an understanding of both phylogenetic/developmental history and the operation of current mechanisms.[1]
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QMrThere are four major disciplines in earth sciences, namely geography, geology, geophysics and geodesy. These major disciplines use physics, chemistry, biology, chronology and mathematics to build a qualitative and quantitative understanding of the principal areas or spheres of the Earth.
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QMRJablonka, Eva (2006). Evolution in Four Dimensions: Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life. Cambridge, MA: MIT Press. ISBN 978-0-262-60069-9.
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QMRQuadrumana and Bimana form an obsolete division of the primates: the Quadrumana are primates with four hands (two attached to the arms and two attached to the legs), and the Bimana are those with two hands and two feet. The attempted division of "Quadrumana" from "Bimana" forms a stage in the long campaign to find a secure way of distinguishing Homo sapiens from the rest of the great apes, a distinction that was culturally essential.[according to whom?]
Quadrumana is Latin for "four-handed ones", which is a term used for apes since they do not have feet attached to their legs as humans do, but instead have hands, as both pairs of hands look almost alike (with the exception of the orangutan, whose hands look exactly the same) and operate exactly like hands.
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QMR Others who followed were more inclined to give humans a special place in classification; Johann Friedrich Blumenbach in the first edition of his Manual of Natural History (1779), proposed that the primates be divided into the Quadrumana (four-handed, i.e. apes and monkeys) and Bimana (two-handed, i.e. humans). This distinction was taken up by other naturalists, most notably Georges Cuvier. Some elevated the distinction to the level of order. However, the many affinities between humans and other primates – and especially the great apes – made it clear that the distinction made no scientific sense. Charles Darwin wrote, in The Descent of Man in 1871:
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QMRFour races[edit]
See also: Race (human categorization)
In the first edition of Systema Naturae, Linnaeus subdivided the human species into four varieties based on continent and skin colour: "Europæus albus" (white European), "Americanus rubescens" (red American), "Asiaticus fuscus" (brown Asian) and "Africanus Niger" (black African). In the tenth edition of Systema Naturae he further detailed stereotypical characteristics for each variety, based on the concept of the four temperaments from classical antiquity, and changed the description of Asians' skin tone to "luridus" (yellow).[175][176][177][178][179] Additionally, Linnaeus created a wastebasket taxon "monstrosus" for "wild and monstrous humans, unknown groups, and more or less abnormal people".[180]
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QMRRoman and the Four Steps was a popular band in Hong Kong in the 1960s.
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QMRMost of the CAMs belong to four protein families: Ig (immunoglobulin) superfamily (IgSF CAMs), the integrins, the cadherins, and the selectins.
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Psychology Chapter
QMRThe Four-Way Test of the things we think, say or do is a test used by Rotarians world-wide as a moral code for personal and business relationships. The test can be applied to almost any aspect of life.[1] The test was scripted by Herbert J. Taylor an American from Chicago as he set out to save the Club Aluminum Products Distribution Company from bankruptcy. It was later adopted by Rotary International, the global federation of Rotary service clubs.[2]
Contents [hide]
1 Genesis
2 Adoption of the test by Rotary
3 Use by the Ghanaian judicial system
4 References
5 External links
Genesis[edit]
In the early 1930s Herbert J. Taylor set out to save the Club Aluminum Products distribution company from bankruptcy. He believed himself to be the only person in the company with 250 employees who had hope. His recovery plan started with changing the ethical climate of the company. He explained:
“ The first job was to set policies for the company that would reflect the high ethics and morals God would want in any business. If the people who worked for Club Aluminum were to think right, I knew they would do right. What we needed was a simple, easily remembered guide to right conduct - a sort of ethical yardstick- which all of us in the company could memorize and apply to what we thought, said and did.
I searched through many books for the answer to our need, but the right phrases eluded me, so I did what I often do when I have a problem I can't answer myself: I turn to the One who has all the answers. I leaned over my desk, rested my head in my hands and prayed. After a few moments, I looked up and reached for a white paper card. Then I wrote down the twenty-four words that had come to me:
Is it the truth?
Is it fair to all concerned?
Will it build goodwill and better friendships?
Will it be beneficial to all concerned?
I called it "The Four-Way Test" of the things we think, say or do."[3]
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QMRAlthough most legal systems recognize the importance of the guilty mind, or mens rea, exactly what is meant by this concept varies. The American Law Institute's Model Penal Code has reduced the mental states to four. In general, guilt can be attributed to an individual who acts "purposely," "knowingly," "recklessly," or "negligently." Together or in combination, these four attributes seem basically effective in dealing with most of the common mens rea issues.[4]
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QMRTypes of styleEdit
The fourth is always different
The term style of life (German: Lebensstil) was used by psychiatrist Alfred Adler as one of several constructs describing the dynamics of the personality.
Adler felt he could distinguish four primary types of style. Three of them he said to be "mistaken styles."
These include:
the ruling type - aggressive, dominating people who don't have much social interest or cultural perception;
the getting type: dependent people who take rather than give;
the avoiding type: people who try to escape life's problems and take little part in socially constructive activity.
The fourth life style considered by Adler is the socially useful type: people with a great deal of social interest and activity.[8]
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Aggressive Communication[edit]
Aggression is defined as an unplanned act of anger in which the aggressor intends to hurt someone or something.[6] Aggressive communicators typically create avoidable conflict by engaging in personal attacks and put-downs.[7] Aggressive communicators create a win-lose situation and use intimidation to get their own needs met, oftentimes at the expense of others.[8] Aggressive communicators typically feel a strong sense of inadequacy, have a lack of empathy, and believe the only way to get their needs met is through power and control.[9] Aggressive communicators are usually close-minded, are poor listeners, and tend to monopolize others.[10]
Behaviors often seen during aggressive communication include: putting others down, overpowering others, not showing appreciation, rushing others unnecessarily, ignoring others, not considering other’s feelings, intimidating others, and speaking in a condescending manner.[11][12] Nonverbal behaviors exhibited during aggressive communication include: frowning, critical glares, rigid posture, trying to stand over others, using a loud voice and fast speech.[13]
While engaging in this type of communications, individuals typically feel anger, superiority, frustration, and impatience.[14] Aggressive communication oftentimes results in counter aggression, alienation, and the creation of resistance or defiance.[15] Additionally, individuals on the receiving end of aggressive communication typically feel: resentful, defensive, humiliated, hurt, and or afraid.[16]
There are times when aggressive communication is pertinent, however. The aggressive communication style is essential during emergencies or when decisions have to be quickly made.[17]
Assertive Communication[edit]
Assertiveness is described as the ability to appropriately expresses one’s own wants and feelings.[18] Assertive communication is thought to be the halfway point between passive communication and aggressive communication.[19] Assertive communication is based on the belief that each individual is responsible for his or her own problems; therefore they are responsible for directly communicating these problems to the other party involved.[20] Assertive communication is a direct form of communication that respects both the communicator’s and the receiver’s rights and opinions.[21] Assertive communication is direct without being argumentative.[22] Engaging in assertive communication helps individuals avoid conflict, maintain relationships, and usually ends in a win-win situation.[23] Assertive communication is the communication style that is least utilized, however.[24]
Individuals who engage in assertive communication are open to hearing the opinions of others, without criticizing their opinions, and feel comfortable enough to express their own opinions as well.[25] Assertive communicators generally have high self-esteem, as they have the confidence to effectively communicate with others without getting offended or being manipulative.[26] While engaging in conversation, assertive communicators will state limits and expectations, state observations without judgment, be an active listener, and check on others feelings.[27] Essential problem solving skills that assertive communicators acquire include negotiations, confronting problems as soon as they arise, and not letting negative feelings build up.[28]
Behaviors that may be present when an individual is engaging in assertive communication include: being open when expressing their thoughts and feelings, encouraging others to openly express their own opinions and feelings, listening to other’s opinions and appropriately responding to them, accepting responsibilities, being action-orientated, being able to admit mistakes, setting realistic goal, maintaining self-control, and acting as an equal to those whom are on the receiving end of the communication,.[29][30]
There are many nonverbal behaviors that represent assertive communication as well. Individuals engaging in assertive communication convey an open and receptive body language, with upright posture and movements that are relaxed.[31] Assertive communicators have a clear tone of voice and make appropriate eye contact.[32] Assertive communicators typically feel more confident and self-respecting while engaging in this type of communication.[33] People on the receiving end of assertive communication typically feel as though they can believe the communicator, know where they stand with the communicator, and possess a sense of respect for the communicator.[34]
Assertive communication has positive effects on both the communicator and the receiver. Some positive effects include: the communicator feels connected to others, the communicator feels in control of their lives, the communicator is able to mature because they address and solve issues as they come up, and creating a respectful environment for others.[35]
Passive
Sociology Chapter
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