wiki143 - User contributions [en]

Intransitive verb

2024-11-26T06:57:17Z

76.71.3.150: /* Ambitransitivity */ {{nihongo krt}}

{{Short description|Verb that does not entail a direct object}}
{{Redirect|Intransitive|intransitive relations in mathematics|Intransitivity||Intransitive (disambiguation)}}
{{Multiple issues|
{{more citations needed|date=May 2014}}
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{{Transitivity and Valency}}

In [[grammar]], an '''intransitive verb''' is a verb, aside from an [[auxiliary verb]], whose context does not entail a transitive [[object (linguistics)|object]]. That lack of an object distinguishes intransitive verbs from [[transitive verb]]s, which entail one or more objects. Additionally, intransitive verbs are typically considered within a class apart from [[modal verb]]s and [[defective verb]]s.

==Examples==
In the following sentences, verbs are used without a [[object (linguistics)|direct object]]:
*"Rivers '''flow'''."
*"I '''sneezed'''."
*"My dog '''ran'''."
*"Water '''evaporates''' when it's hot."
*"You've '''grown''' since I last saw you!"
*"I wonder how long it will be until I see you again after I '''move'''."

The following sentences contain [[transitive verb]]s (they entail one or more objects):
*"We '''watched''' ''a movie'' last night."
*"She's '''making''' ''promises''."
*"When I said that, my sister '''smacked''' ''me''."
*"Santa '''gave''' ''me'' ''a present''."
*"He continuously '''clicked''' ''his pen'' and it was incredibly annoying to me."

Some verbs, called [[ambitransitive verb]]s, may entail objects but do not always require one. Such a verb may be used as intransitive in one sentence, and as transitive in another.

:{|
! Intransitive !! !! Transitive
|-
|"It is '''raining'''." || || "It is '''raining''' ''cats and dogs''."
|-
| "When he finished the race, he '''vomited'''." || || "When he finished the race, he '''vomited up''' ''his lunch''."
|-
| "Water '''evaporates''' when it's hot." || || "Heat '''evaporates''' ''water''."
|-
| "He's been '''singing''' all day." || || "He's been '''singing''' ''barbershop'' all day."
|-
| "You've '''grown''' since I last saw you." || || "You've '''grown''' ''a beard'' since I last saw you!"
|}

In general, intransitive verbs often involve weather terms, involuntary processes, states, bodily functions, motion, action processes, cognition, sensation, and emotion.<ref name=Morphosyntax>Payne, Thomas E. (1997). [https://books.google.com/books?id=LC3DfjWfCiwC Describing morphosyntax: A guide for field linguists]. Cambridge: Cambridge University Press.</ref>{{rp|54–61}}

==Valency-changing operations==
The [[Valency (linguistics)|valency]] of a verb is related to transitivity. Where the transitivity of a verb only considers the objects, the valency of a verb considers all the [[Verb argument|arguments]] that correspond to a verb, including both the subject of the verb and all of the objects.

It is possible to change the contextually indicated sense of a verb from transitive to intransitive, and in so doing to change the [[Valency (linguistics)|valency]].

In languages that have a [[passive voice]], a transitive verb in the active voice becomes intransitive in the passive voice. For example, consider the following sentence:

{{block indent|''David hugged Mary.''}}

In this sentence, "hugged" is a transitive verb with "Mary" as its object. The sentence can be made passive with the direct object "Mary" as the [[subject (grammar)|grammatical subject]] as follows:

{{block indent|''Mary was hugged.''}}

This shift is called ''promotion'' of the object.

The passive-voice construction does not indicate an object. The passivized sentence could be continued with the [[Agent (grammar)|agent]]:

{{block indent|''Mary was hugged by David.''}}

It cannot be continued with a direct object to be taken by "was hugged". For example, it would be ungrammatical to write "Mary was hugged her daughter" to show that Mary and her daughter shared a hug.

Intransitive verbs can be rephrased as passive constructs in some languages. In English, intransitive verbs can be used in the passive voice when a prepositional phrase is included, as in, "The houses were lived in by millions of people."

Some languages, such as [[Dutch language|Dutch]], have an [[impersonal passive voice]] that lets an intransitive verb without a prepositional phrase be passive. In [[German language|German]], a sentence such as "The children sleep" can be made passive to remove the subject and becomes, "They are slept." However, no addition like "... by the children" is possible in such cases.

In languages with [[ergative–absolutive language|ergative–absolutive alignment]], the passive voice (where the object of a transitive verb becomes the subject of an intransitive verb) does not make sense, because the noun associated with the intransitive verb is marked as the object, not as the subject. Instead, these often have an [[antipassive voice]]. In this context, the ''subject'' of a transitive verb is promoted to the "object" of the corresponding intransitive verb. In the context of a [[nominative–accusative language]] like English, this promotion is nonsensical because intransitive verbs do not entail objects, they entail subjects. So, the subject of a transitive verb ("I" in ''I hug him'') is ''also'' the subject of the intransitive passive construction (''I was hugged by him''). But in an ergative–absolutive language like [[Dyirbal language|Dyirbal]], "I" in the transitive ''I hug him'' would involve the [[ergative case]], but the "I" in ''I was hugged'' would involve the [[absolutive case|absolutive]], and so by analogy the antipassive construction more closely resembles ''*was hugged me''. Thus in this example, the ergative is promoted to the absolutive, and the agent (i.e., ''him''), which was formerly marked by the absolutive, is deleted to form the antipassive voice (or is marked in a different way, in the same way that in the English passive voice can still be specified as the agent of the action using ''by him'' in ''I was hugged by him''—for example, Dyirbal puts the agent in the [[dative case]], and [[Basque language|Basque]] retains the agent in the absolutive).

==Ambitransitivity==
{{Main article|Ambitransitive verb}}
In many languages, there are "ambitransitive" verbs, which can occur either in a transitive or intransitive sense. For example, English ''play'' is ambitransitive, since it is grammatical to say ''His son plays'', and it is also grammatical to say ''His son plays guitar''. English is rather flexible as regards verb valency, and so it has a high number of ambitransitive verbs; other languages are more rigid and require explicit valency changing operations ([[grammatical voice|voice]], [[causative]] morphology, etc.) to transform a verb from intransitive to transitive or vice versa.

In some ambitransitive verbs are ''[[ergative verb]]s'' for which the alignment of the syntactic arguments to the semantic roles is exchanged. An example of this is the verb ''break'' in English.

:(1) ''{{green|He}} broke {{maroon|the cup}}.''
:(2) ''{{maroon|The cup}} broke.''

In (1), the verb is transitive, and the subject is the ''agent'' of the action, i.e. the performer of the action of breaking the cup. In (2), the verb is intransitive and the subject is the ''patient'' of the action, i.e. it is the thing affected by the action, not the one that performs it. In fact, the patient is the same in both sentences, and sentence (2) is an example of implicit [[middle voice]]. This has also been termed an ''anticausative''.

Other alternating intransitive verbs in English are ''change'' and ''sink''.

In the [[Romance language]]s, these verbs are often called ''pseudo-reflexive'', because they are signaled in the same way as [[reflexive verb]]s, using the [[clitic]] particle ''se''. Compare the following (in [[Spanish language|Spanish]]):

:(3a) {{lang|es|La taza se rompió.}} ("The cup broke.")
:(3b) {{lang|es|El barco se hundió.}} ("The boat sank.")
:(4a) {{lang|es|Ella se miró en el espejo.}} ("She looked at herself in the mirror.")
:(4b) {{lang|es|El gato se lava.}} ("The cat washes itself.")

Sentences (3a) and (3b) show Romance pseudo-reflexive phrases, corresponding to English alternating intransitives. As in ''The cup broke'', they are inherently without an agent; their [[deep structure]] does not and can not contain one. The action is not reflexive (as in (4a) and (4b)) because it is not performed by the subject; it just happens to it. Therefore, this is not the same as [[passive voice]], where an intransitive verb phrase appears, but there is an implicit agent (which can be made explicit using a complement phrase):

:(5) ''The cup was broken (by the child).''
:(6) {{lang|es|El barco fue hundido (por piratas).}} ("The boat was sunk (by pirates).")

Other ambitransitive verbs (like ''eat'') are not of the alternating type; the subject is always the agent of the action, and the object is simply optional. A few verbs are of both types at once, like ''read'': compare ''I read'', ''I read a magazine'', and ''this magazine reads easily''.

Some languages like Japanese have different forms of certain verbs to show transitivity. For example, there are two forms of the verb "to start":

: (7) {{Nihongo krt|"The meeting starts."|会議が始まる。|Kaigi ga hajimaru.}}

: (8) {{Nihongo krt|"The president starts the meeting."|会長が会議を始める。|Kaichō ga kaigi o hajimeru.}}

In Japanese, the form of the verb indicates the number of arguments the sentence needs to have.<ref>Tsujimura, N., ed. by Natalia Gagarina and I. Gülzow (2007). The acquisition of verbs and their grammar : the effect of particular languages. Dordrecht [u.a.]: Springer. p. 106. {{ISBN|978-1-4020-4336-9}}.</ref>

==Unaccusative and unergative verbs==
{{Main article|Unaccusative verb|Unergative verb}}
Especially in some languages, it makes sense to classify intransitive verbs as:
*''unaccusative'' when the subject is not an agent; that is, it does not actively initiate the action of the verb (e.g. "die", "fall").
**Unaccusative verbs are typically used to show action or movement.
***Examples:
****I '''arrived''' at the party around 8 o'clock.
****Do you know what time the plane '''departed'''?
****The disease '''spread''' to other towns.<ref>{{Cite web|url=http://primus.arts.u-szeged.hu/bese/Chapter5/5.2.1.htm|title=Basic English Syntax with Exercised|last=Konzorcium|first=Bolcsesz|access-date=March 5, 2017}}</ref>
****I '''sat''' on the train.
****I was in a car accident and the other person '''appeared''' out of no where.
*''unergative'' when they have an agent subject.
**Examples:
***I am going to '''resign''' from my position at the bank.
***I have to '''run''' six miles in the morning.
***John '''ate'''.<ref>{{Cite web|url=http://web.mit.edu/norvin/www/24.902/unaccusatives.html|title=Unergatives and Unaccusatives}}</ref>

This distinction may in some cases be reflected in the grammar, where for instance different [[auxiliary verb]]s may be used for the two categories.

==Cognate objects==
{{Main article|Cognate object}}
In many languages, including English, some or all intransitive verbs can entail ''cognate objects''—objects formed from the same roots as the verbs themselves; for example, the verb ''sleep'' is ordinarily intransitive, but one can say, "He slept a troubled sleep", meaning roughly "He slept, and his sleep was troubled."

== Other languages ==
In [[Pingelapese language|Pingelapese]], a [[Micronesian language]], intransitive verb sentence structure is often used, with no object attached. There must be a stative or active verb to have an intransitive sentence. A stative verb has a person or an object that is directly influenced by a verb. An active verb has the direct action performed by the subject. The [[word order]] that is most commonly associated with intransitive sentences is [[subject-verb]]. However, [[verb-subject]] is used if the verb is unaccusative or by discourse pragmatics.<ref>{{Cite thesis |last=Hattori|first= Ryoko|publisher=University of Hawaii at Manoa|date=August 2012|degree=PhD in Linguistics |title=Preverbal particles in Pingelapese: A language of Micronesia|id = {{ProQuest|1267150306}}}}</ref>

In [[Tokelauan language|Tokelauan]], the noun phrases used with verbs are required when verbs are placed in groups. Verbs are divided into two major groups. Every verbal sentence must have that structure, which contains a singular noun phrase, without a preposition, called an unmarked noun phrase. Only if a ''ko''-phrase precedes the predicate, that rule may be ignored. The agent is what speakers of the language call the person who is performing the action of the verb. If a noun phrase that starts with the preposition ''e'' is able to express the agent, and the receiving person or thing that the agent is performing the action of the verb to is expressed by a singular noun phrase that lack a preposition, or unmarked noun phrase, the verb is then considered transitive. All other verbs are considered intransitive.<ref>{{cite book|last1=Simona|first1=Ropati|title=Tokelau Dictionary|date=1986|publisher=Office of Tokelau Affairs|location=New Zealand|page=Introduction}}</ref>

==See also==
*[[Transitivity (grammatical category)]]
*[[Transitive verb]]s
*[[Verb]]s
*[[Ditransitive verb]]s
*[[Valency (linguistics)]]
*[[Morphosyntactic alignment]]
*[[English passive voice]]

==References==
{{Reflist}}

{{lexical categories|state=collapsed}}
{{Authority control}}

{{DEFAULTSORT:Intransitive Verb}}
[[Category:Transitivity and valency]]

Imbibition

2024-11-26T03:36:43Z

76.71.3.150: /* Radicle growth */ gr

{{Short description|Absorption of liquid by a colloid}}
{{about|the absorption of water by a [[colloid]]|the ingestion of a fluid by an animal|Drinking}}

{{refimprove|date=November 2019}}

'''Imbibition''' is a special type of [[diffusion]] that takes place when liquid is absorbed by solids-[[Colloid|colloids]] causing an increase in volume. Water surface potential movement takes place along a concentration gradient; some dry materials absorb water. A gradient between the absorbent and the liquid is essential for imbibition. For a substance to imbibe a liquid, there must first be some attraction between them. Imbibition occurs when a [[wetting]] fluid displaces a non-wetting fluid, the opposite of drainage in which a non-wetting phase displaces the wetting fluid. The two processes are governed by different mechanisms.{{clarify|date=November 2019}} Imbibition is also a type of diffusion since water movement is along the concentration gradient. Seeds and other such materials have almost no water hence they absorb water easily. Water potential gradient between the absorbent and liquid imbibed is essential for imbibition.

== Examples ==
One example of Imbibition in nature is the [[absorption (chemistry)|absorption]] of water by [[hydrophilic]] [[colloids]]. [[Water_potential#Matrix_potential_.28Matric_potential.29|Matrix potential]] contributes significantly to water in such substances. Dry seeds germinate in part by imbibition. Imbibition can also control circadian rhythms in ''[[Arabidopsis thaliana]]'' and (probably) other plants. The [[Amott test]] employs imbibition.

Proteins have high imbibition capacities, so proteinaceous pea seeds swell more than starchy wheat seeds.

Imbibition of water increases imbibant volume, which results in imbibitional pressure (IP). The magnitude of such pressure can be demonstrated by the splitting of rocks by inserting dry wooden stalks in their crevices and soaking them in water, a technique used by early Egyptians to cleave stone blocks.<ref>{{cite web | url=http://www.reshafim.org.il/ad/egypt/building/building_in_stone.htm | title=Building With Stone | access-date=2008-05-03 | archive-url=https://web.archive.org/web/20170101113445/http://www.reshafim.org.il/ad/egypt/building/building_in_stone.htm | archive-date=2017-01-01 | url-status=dead }}</ref><ref>{{cite web | url=http://www.deccanherald.com/deccanherald/jan62006/sesame144058200615.asp | title=The Pyramid Puzzle - Deccan Herald | access-date=2006-12-11 | archive-date=2007-02-04 | archive-url=https://web.archive.org/web/20070204015414/http://www.deccanherald.com/deccanherald/jan62006/sesame144058200615.asp | url-status=live }}</ref>

[[Skin graft]]s (split thickness and full thickness) receive oxygenation and nutrition via imbibition, maintaining cellular viability until the processes of [[inosculation]] and [[revascularisation]] have re-established a new blood supply within these tissues.

===Germination===
[[File:Prunus armeniaca dry and imbibed seed.jpg|thumb|An [[Prunus armeniaca|apricot]] seed, dry (l) & imbibed (r)]]

Examples include the absorption of water by seeds<ref>{{Cite web|url=http://openagricola.nal.usda.gov/Record/IND89001759|title=Soybean seed imbibition: water absorption by seed parts.|website=openagricola.nal.usda.gov|access-date=2016-03-19|archive-url=https://web.archive.org/web/20161022100132/http://openagricola.nal.usda.gov/Record/IND89001759|archive-date=2016-10-22|url-status=dead}}</ref> and dry wood. If there is no pressure due to imbibition, seedlings would not be able to emerge from soil.{{Speculation-inline}}

====Radicle growth====
The [[radicle]] is the first part of a seedling (a growing plant [[embryo]]) to emerge from the [[seed]] during the process of [[germination]].<ref name="Schiltz">{{cite journal |last1=Schiltz |first1=S |last2=Gaillard |first2=I |last3=Pawlicki-Jullian |first3=N |last4=Thiombiano |first4=B |last5=Mesnard |first5=F |last6=Gontier |first6=E |title=A review: what is the spermosphere and how can it be studied? |journal=Journal of Applied Microbiology |date=December 2015 |volume=119 |issue=6 |pages=1467–81 |doi=10.1111/jam.12946 |pmid=26332271|s2cid=42515027 |doi-access= }}</ref> The radicle is the embryonic [[root]] of the plant, and grows downward in the soil (the shoot emerges from the [[plumule]]) where it absorbs more water. Most of the seed is stored energy so nutrients are not essential during the first days for the seedling.

==See also==
* [[Amott test]]
* [[Dye-transfer process]]
* [[Syneresis (chemistry)]]
* [[Technicolor]]

==References==
<references/>

[[Category:Biological processes]]
[[Category:Colloids| ]]
[[Category:Chemical mixtures]]
[[Category:Colloidal chemistry]]

Klenow fragment

2024-11-25T22:46:00Z

76.71.3.150: /* The exo- Klenow fragment */ not MOS:HANGING

{{Short description|Large protein fragment}}
[[Image:PolymeraseDomains.jpg|right|thumb|450px|{{center|Functional domains in the Klenow Fragment (left) and DNA Polymerase I (PDB).}}]]
The '''Klenow fragment''' is a large [[protein]] fragment produced when [[DNA polymerase I]] from ''[[E. coli]]'' is [[enzyme|enzymatically]] cleaved by the [[protease]] [[subtilisin]]. First reported in 1970,<ref>{{cite journal| author=Klenow H and Henningsen I | title=Selective Elimination of the Exonuclease Activity of the Deoxyribonucleic Acid Polymerase from Escherichia coli B by Limited Proteolysis| journal= Proc. Natl. Acad. Sci. USA| volume= 65 |pages=168–175 | year=1970 | pmid=4905667 | doi = 10.1073/pnas.65.1.168 | issue=1| pmc=286206| bibcode=1970PNAS...65..168K| doi-access=free}}</ref> it retains the 5' → 3' [[polymerase]] activity and the 3’ → 5’ [[exonuclease]] activity for removal of precoding nucleotides and proofreading, but loses its 5' → 3' exonuclease activity.

The other smaller fragment formed when DNA polymerase I from ''[[E. coli]]'' is cleaved by subtilisin retains the 5' → 3' exonuclease activity but does not have the other two activities exhibited by the Klenow fragment (i.e. 5' → 3' polymerase activity, and 3' → 5' exonuclease activity).

==Research==
Because the 5' → 3' exonuclease activity of DNA polymerase I from ''[[E. coli]]'' makes it unsuitable for many applications, the Klenow fragment, which lacks this activity, can be very useful in research. The Klenow fragment is extremely useful for research-based tasks such as:

* Synthesis of double-stranded DNA from single-stranded templates
* Filling in receded 3' ends of DNA fragments to make 5' overhang blunt
* Digesting away protruding 3' overhangs
* Preparation of [[radioactive]] [[DNA probe]]s

The Klenow fragment was also the original enzyme used for greatly amplifying segments of DNA in the [[polymerase chain reaction]] (PCR) process,<ref name=Saiki1>{{cite journal |vauthors=Saiki RK, etal | title=Enzymatic Amplification of β-globin Genomic Sequences and Restriction Site Analysis for Diagnosis of Sickle Cell Anemia| journal= Science| volume= 230| pages=1350–54 | year= 1985 | issue=4732| pmid = 2999980 | doi = 10.1126/science.2999980 | bibcode=1985Sci...230.1350S}}</ref> before being replaced by [[thermostable DNA polymerase]]s such as [[Taq polymerase]].<ref name=Saiki3>{{cite journal |vauthors=Saiki RK, etal | title=Primer-directed enzymatic amplification of DNA with a thermostable DNA polymerase | journal= Science | volume= 239| pages=487–91 | year=1988 | issue=4839 | pmid = 2448875 | doi = 10.1126/science.239.4839.487 |display-authors=etal}}</ref>

==The exo-Klenow fragment==
Just as the 5' → 3' [[exonuclease]] activity of [[DNA polymerase I]] from ''[[E.coli]]'' can be undesirable, the 3' → 5' [[exonuclease]] activity of Klenow fragment can also be undesirable for certain applications. This problem can be overcome by introducing [[mutation]]s in the gene that encodes Klenow. This results in forms of the enzyme being expressed that retain 5' → 3' polymerase activity, but lack any [[exonuclease]] activity (5' → 3' or 3' → 5'). This form of the enzyme is called the '''exo-Klenow fragment'''.

The exo-Klenow fragment is used in some fluorescent labeling reactions for microarray, and also in dA and dT tailing, an important step in the process of ligating DNA adapters to DNA fragments, frequently used in preparing DNA libraries for Next-Gen sequencing. (for instance see [https://www.abmgood.com/Documents/files/E009-DNA-dA-Tailing-Kit.pdf])

==References==
{{reflist}}

==External links==
* {{MeshName|Klenow+Fragment}}
* [https://web.archive.org/web/20061115090104/http://www.vivo.colostate.edu/hbooks/genetics/biotech/enzymes/klenow.html Diagram at vivo.colostate.edu]

{{DNA replication}}

[[Category:DNA replication]]

Maltose-binding protein

2024-11-25T22:39:09Z

76.71.3.150: /* Use as a protein and peptide vector */ gr

{{Infobox nonhuman protein
|image=1fqc mbp.png
|caption=Maltose-binding protein from ''[[Escherichia coli]]'', with a bound sugar molecule shown as red spheres, from {{PDB|1FQC}}.<ref name="duan_2001">{{cite journal |last1=Duan |first1=Xiaoqun |last2=Hall |first2=Jason A |last3=Nikaido |first3=Hiroshi |last4=Quiocho |first4=Florante A |title=Crystal structures of the maltodextrin/maltose-binding protein complexed with reduced oligosaccharides: flexibility of tertiary structure and ligand binding |journal=Journal of Molecular Biology |date=March 2001 |volume=306 |issue=5 |pages=1115–1126 |doi=10.1006/jmbi.2001.4456|pmid=11237621 }}</ref>
|Name=Maltose/maltodextrin-binding periplasmic protein
|Organism=Escherichia coli
|TaxID = 1010810
|Symbol=MalE
|UniProt=P0AEX9
}}
'''Maltose-binding protein''' ('''MBP''') is a part of the [[maltose]]/[[maltodextrin]] system of ''[[Escherichia coli]]'', which is responsible for the uptake and efficient [[catabolism]] of maltodextrins. It is a complex regulatory and transport system involving many [[protein]]s and protein complexes. MBP has an approximate molecular mass of 42.5 [[dalton (unit)|kilodaltons]].

==Structure and folding==
MBP is encoded by the ''malE'' [[gene]] of ''Escherichia coli''. The ''malE'' gene codes for a precursor polypeptide (396 [[amino acid]] residues) which yields the mature MBP (370 residues) upon cleavage of the [[N-terminus|NH2-terminal]] extension (26 residues). The precursor and mature forms of MBP do not contain any [[cysteine]] residues.<ref>{{cite journal | vauthors = Duplay P, Bedouelle H, Fowler A, Zabin I, Saurin W, Hofnung M | title = Sequences of the malE gene and of its product, the maltose-binding protein of Escherichia coli K12 | journal = The Journal of Biological Chemistry | volume = 259 | issue = 16 | pages = 10606–13 | date = August 1984 | doi = 10.1016/S0021-9258(18)91005-7 | pmid = 6088507 | doi-access = free }}</ref>

MBP is a monomeric protein. Crystal structures have shown that MBP is divided into two distinct globular [[protein domain|domains]] that are connected by three short polypeptide segments. The two domains are separated by a deep groove that contains the maltose/maltodextrin binding site. Comparison of the structures of the liganded and unliganded forms of MBP has shown that the binding of maltose induces a major [[conformational change]] that closes the groove by a rigid motion of the two domains around the linking polypeptide hinge.<ref>{{cite journal | vauthors = Spurlino JC, Lu GY, Quiocho FA | title = The 2.3-A resolution structure of the maltose- or maltodextrin-binding protein, a primary receptor of bacterial active transport and chemotaxis | journal = The Journal of Biological Chemistry | volume = 266 | issue = 8 | pages = 5202–19 | date = March 1991 | doi = 10.2210/pdb1mbp/pdb | pmid = 2002054 }}</ref><ref>{{cite journal | vauthors = Sharff AJ, Rodseth LE, Spurlino JC, Quiocho FA | title = Crystallographic evidence of a large ligand-induced hinge-twist motion between the two domains of the maltodextrin binding protein involved in active transport and chemotaxis | journal = Biochemistry | volume = 31 | issue = 44 | pages = 10657–63 | date = November 1992 | pmid = 1420181 | doi = 10.1021/bi00159a003 }}</ref>

Both precursor and mature forms of MBP are functional for the binding of maltose.<ref>{{cite journal | vauthors = Ferenci T, Randall LL | title = Precursor maltose-binding protein is active in binding substrate | journal = The Journal of Biological Chemistry | volume = 254 | issue = 20 | pages = 9979–81 | date = October 1979 | doi = 10.1016/S0021-9258(19)86659-0 | pmid = 385604 | doi-access = free }}</ref> The NH2-terminal extension decreases the [[protein folding|folding]] rate of the precursor form of MBP relative to its mature form by at least 5 fold, but it has no effect on the unfolding rate.<ref>{{cite journal | vauthors = Park S, Liu G, Topping TB, Cover WH, Randall LL | title = Modulation of folding pathways of exported proteins by the leader sequence | journal = Science | volume = 239 | issue = 4843 | pages = 1033–5 | date = February 1988 | pmid = 3278378 | doi = 10.1126/science.3278378 | bibcode = 1988Sci...239.1033P }}</ref><ref>{{cite journal | vauthors = Beena K, Udgaonkar JB, Varadarajan R | title = Effect of signal peptide on the stability and folding kinetics of maltose binding protein | journal = Biochemistry | volume = 43 | issue = 12 | pages = 3608–19 | date = March 2004 | pmid = 15035631 | doi = 10.1021/bi0360509 }}</ref> The equilibrium unfolding of MBP can be modelled by a two-state mechanism with a stability ∆G(H2O) equal to 9.45 kcal mol−1 at 25 °C, pH 7.6.<ref>{{cite journal | vauthors = Chun SY, Strobel S, Bassford P, Randall LL | title = Folding of maltose-binding protein. Evidence for the identity of the rate-determining step in vivo and in vitro | journal = The Journal of Biological Chemistry | volume = 268 | issue = 28 | pages = 20855–62 | date = October 1993 | doi = 10.1016/S0021-9258(19)36864-4 | pmid = 8407916 | doi-access = free }}</ref>

==Localization and export==
MBP is exported into the [[periplasmic space]] of ''E. coli''.<ref>{{cite journal | vauthors = Kellermann O, Szmelcman S | title = Active transport of maltose in Escherichia coli K12. Involvement of a "periplasmic" maltose binding protein | journal = European Journal of Biochemistry | volume = 47 | issue = 1 | pages = 139–49 | date = August 1974 | pmid = 4215651 | doi = 10.1111/j.1432-1033.1974.tb03677.x | doi-access = free }}</ref> The NH2-terminal extension of MBP, also termed [[signal peptide]], has two roles: (i) it slows down folding of the newly synthesized polypeptide, and (ii) it directs this polypeptide to the membrane and SecYEG [[translocon]]. Once folded, the precursor can no longer enter the translocation pathway.<ref>{{cite journal | vauthors = Randall LL, Hardy SJ | title = Correlation of competence for export with lack of tertiary structure of the mature species: a study in vivo of maltose-binding protein in E. coli | journal = Cell | volume = 46 | issue = 6 | pages = 921–8 | date = September 1986 | pmid = 3530497 | doi = 10.1016/0092-8674(86)90074-7 | s2cid = 28503725 }}</ref> The introduction of a charged amino-acid residue or a [[proline]] residue within the hydrophobic core of the signal peptide is sufficient to block export.<ref>{{cite journal | vauthors = Bedouelle H, Bassford PJ, Fowler AV, Zabin I, Beckwith J, Hofnung M | title = Mutations which alter the function of the signal sequence of the maltose binding protein of Escherichia coli | journal = Nature | volume = 285 | issue = 5760 | pages = 78–81 | date = May 1980 | pmid = 6990274 | doi = 10.1038/285078a0 | bibcode = 1980Natur.285...78B | s2cid = 4253747 }}</ref> The defective exports of the mutant MBPs are consistent with the alpha-helical conformation and hydrophobic interactions of the signal peptide in its interaction with the translocon motor protein [[SecA]].<ref>{{cite journal | vauthors = Bedouelle H, Hofnung M | title = Functional implications of secondary structure analysis of wild type and mutant bacterial signal peptides | journal = Progress in Clinical and Biological Research | volume = 63 | pages = 399–403 | date = 1981 | pmid = 7312870 }}</ref><ref>{{cite journal | vauthors = Chou YT, Gierasch LM | title = The conformation of a signal peptide bound by Escherichia coli preprotein translocase SecA | journal = The Journal of Biological Chemistry | volume = 280 | issue = 38 | pages = 32753–60 | date = September 2005 | pmid = 16046390 | doi = 10.1074/jbc.M507532200 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Gelis I, Bonvin AM, Keramisanou D, Koukaki M, Gouridis G, Karamanou S, Economou A, Kalodimos CG | title = Structural basis for signal-sequence recognition by the translocase motor SecA as determined by NMR | journal = Cell | volume = 131 | issue = 4 | pages = 756–69 | date = November 2007 | pmid = 18022369 | pmc = 2170882 | doi = 10.1016/j.cell.2007.09.039 }}</ref>

==Control of expression==
The ''malE'' gene, coding for MBP, belongs to the [[Mal regulon]] of ''E. coli'', which consists of ten genes whose products are geared for the efficient uptake and utilization of [[maltose]] and [[maltodextrins]]. All the gene involved in the transport of maltose/maltodextrin, including ''malE'', are clustered in the ''malB'' region of ''E. coli'' and organized in two divergent [[operons]]: ''malE-malF-malG'' and ''malK-lamB''.<ref>{{cite journal | vauthors = Boos W, Shuman H | title = Maltose/maltodextrin system of Escherichia coli: transport, metabolism, and regulation | journal = Microbiology and Molecular Biology Reviews | volume = 62 | issue = 1 | pages = 204–29 | date = March 1998 | doi = 10.1128/MMBR.62.1.204-229.1998 | pmid = 9529892 | pmc = 98911 }}</ref> The [[transcription (genetics)|transcription]] start sites at the ''malEp'' and ''malKp'' [[promoter (genetics)|promoters]] are distant of 271 base pairs.<ref name="pmid6185687">{{cite journal | vauthors = Bedouelle H, Schmeissner U, Hofnung M, Rosenberg M | title = Promoters of the malEFG and malK-lamB operons in Escherichia coli K12 | journal = Journal of Molecular Biology | volume = 161 | issue = 4 | pages = 519–31 | date = November 1982 | pmid = 6185687 | doi = 10.1016/0022-2836(82)90405-3 }}</ref>

The ''malEp'' and ''malKp'' promoters are synergistically activated by protein MalT, the activator of the Mal regulon and by the [[cAMP receptor protein]] CRP. This activation is a coupled process that involves, going from ''malEp'' towards ''malKp'': two MalT binding sites; three CRP binding sites, and two overlapping sets of three MalT binding sites, staggered by three base pairs.<ref name="pmid6185687" /><ref>{{cite journal | vauthors = Bedouelle H | title = Mutations in the promoter regions of the malEFG and malK-lamB operons of Escherichia coli K12 | journal = Journal of Molecular Biology | volume = 170 | issue = 4 | pages = 861–82 | date = November 1983 | pmid = 6417341 | doi = 10.1016/s0022-2836(83)80192-2 }}</ref><ref>{{cite journal | vauthors = Richet E | title = Synergistic transcription activation: a dual role for CRP in the activation of an Escherichia coli promoter depending on MalT and CRP | journal = The EMBO Journal | volume = 19 | issue = 19 | pages = 5222–32 | date = October 2000 | pmid = 11013224 | pmc = 302108 | doi = 10.1093/emboj/19.19.5222 }}</ref> Transcription activation requires the binding of [[adenosine triphosphate]] (ATP) and [[maltotriose]] to MalT and the binding of [[cyclic AMP]] to the dimer of CRP.<ref>{{cite journal | vauthors = Richet E, Raibaud O | title = MalT, the regulatory protein of the Escherichia coli maltose system, is an ATP-dependent transcriptional activator | journal = The EMBO Journal | volume = 8 | issue = 3 | pages = 981–7 | date = March 1989 | pmid = 2524384 | pmc = 400900 | doi = 10.1002/j.1460-2075.1989.tb03461.x }}</ref> The unliganded form of MalT is monomeric whereas its liganded form, in the presence of ATP and maltotriose, is oligomeric.<ref>{{cite journal | vauthors = Schreiber V, Richet E | title = Self-association of the Escherichia coli transcription activator MalT in the presence of maltotriose and ATP | journal = The Journal of Biological Chemistry | volume = 274 | issue = 47 | pages = 33220–6 | date = November 1999 | pmid = 10559195 | doi = 10.1074/jbc.274.47.33220 | doi-access = free }}</ref>

==Use as a protein and peptide vector{{Anchor|MBP-tag}}==
MBP is used to increase the solubility of [[recombinant protein]]s expressed in ''E. coli''. In these systems, the protein of interest is often expressed as a MBP-[[fusion protein]], preventing aggregation of the protein of interest. The mechanism by which MBP increases solubility is not well understood. In addition, MBP can itself be used as an [[affinity tag]] for [[protein purification|purification]] of recombinant proteins. The fusion protein binds to [[amylose]] [[chromatography column|columns]] while all other proteins flow through. The MBP-protein fusion can be purified by eluting the column with maltose. Once the fusion protein is obtained in purified form, the protein of interest is often cleaved from MBP with a specific [[protease]] and can then be separated from MBP by [[affinity chromatography]].

A first study of the relations between structure and functions of MBP was performed by random insertion of a short DNA fragment, coding for a [[BamHI]] [[restriction site]], into the ''malE'' gene. Some of the insertions affected the functions of MBP whereas others were permissive.<ref>{{cite journal | vauthors = Duplay P, Bedouelle H, Szmelcman S, Hofnung M | title = Linker mutagenesis in the gene encoding the periplasmic maltose-binding protein of E. coli | journal = Biochimie | volume = 67 | issue = 7–8 | pages = 849–51 | date = 1985 | pmid = 3002495 | doi = 10.1016/s0300-9084(85)80178-4 }}</ref><ref>{{cite journal | vauthors = Duplay P, Szmelcman S, Bedouelle H, Hofnung M | title = Silent and functional changes in the periplasmic maltose-binding protein of Escherichia coli K12. I. Transport of maltose | journal = Journal of Molecular Biology | volume = 194 | issue = 4 | pages = 663–73 | date = April 1987 | pmid = 2821264 | doi = 10.1016/0022-2836(87)90243-9 }}</ref> The permissive sites that were internal to MBP, were used to insert antigenic peptides and challenge the immune response in mice.<ref>{{cite journal | vauthors = Coëffier E, Clément JM, Cussac V, Khodaei-Boorane N, Jehanno M, Rojas M, Dridi A, Latour M, El Habib R, Barré-Sinoussi F, Hofnung M, Leclerc C | title = Antigenicity and immunogenicity of the HIV-1 gp41 epitope ELDKWA inserted into permissive sites of the MalE protein | journal = Vaccine | volume = 19 | issue = 7–8 | pages = 684–93 | date = November 2000 | pmid = 11115689 | doi = 10.1016/s0264-410x(00)00267-x }}</ref> The 3'-OH terminal insertions were used to create fusion proteins and develop the use of MBP as an affinity handle for the purification of foreign proteins and peptides by affinity chromatography on cross-linked amylose and elution with maltose in mild physico-chemical conditions.<ref name="pmid3278900">{{cite journal | vauthors = Bedouelle H, Duplay P | title = Production in Escherichia coli and one-step purification of bifunctional hybrid proteins which bind maltose. Export of the Klenow polymerase into the periplasmic space | journal = European Journal of Biochemistry | volume = 171 | issue = 3 | pages = 541–9 | date = February 1988 | pmid = 3278900 | doi = 10.1111/j.1432-1033.1988.tb13823.x | doi-access = free }}</ref><ref>{{cite journal | vauthors = Rondard P, Brégégère F, Lecroisey A, Delepierre M, Bedouelle H | title = Conformational and functional properties of an undecapeptide epitope fused with the C-terminal end of the maltose binding protein | journal = Biochemistry | volume = 36 | issue = 29 | pages = 8954–61 | date = July 1997 | pmid = 9220983 | doi = 10.1021/bi962508d | citeseerx = 10.1.1.599.2650 }}</ref> Several [[plasmid vector]]s were developed to facilitate the expression and purification of such fusion proteins.<ref>{{cite journal | vauthors = di Guan C, Li P, Riggs PD, Inouye H | title = Vectors that facilitate the expression and purification of foreign peptides in Escherichia coli by fusion to maltose-binding protein | journal = Gene | volume = 67 | issue = 1 | pages = 21–30 | date = July 1988 | pmid = 2843437 | doi = 10.1016/0378-1119(88)90004-2 }}</ref>

When the recombinant MBP includes a [[signal peptide]], the fusion protein can be exported into the [[periplasmic space]], which facilitates its purification since the periplasmic fluid contains only a limited number of proteins and can be recovered either by an [[osmotic shock]] or by permeabilization of the [[bacterial outer membrane]] with [[antibiotics]] such as [[Polymyxin B]]. Such an export of the fusion protein into the periplasmic space enables the formation of [[disulfide bond]]s in the passenger protein, for example [[antibody]] fragments.<ref>{{cite journal | vauthors = Brégégère F, Schwartz J, Bedouelle H | title = Bifunctional hybrids between the variable domains of an immunoglobulin and the maltose-binding protein of Escherichia coli: production, purification and antigen binding | journal = Protein Engineering | volume = 7 | issue = 2 | pages = 271–80 | date = February 1994 | pmid = 8170930 }}</ref><ref>{{cite journal | vauthors = Malik A | title = Protein fusion tags for efficient expression and purification of recombinant proteins in the periplasmic space of E. coli | journal = 3 Biotech | volume = 6 | issue = 1 | pages = 44 | date = June 2016 | pmid = 28330113 | pmc = 4742420 | doi = 10.1007/s13205-016-0397-7 }}</ref> Foreign proteins that are exported or secreted in their native organism, can usually be exported into the ''E. coli'' periplasm by fusion with MBP. Examples of cytoplasmic proteins that could be exported by fusion with MBP, include the monomeric [[Klenow polymerase]] and the dimeric Gene V protein of [[M13 bacteriophage|phage M13]].<ref name="pmid3278900" /><ref>{{cite journal | vauthors = Blondel A, Bedouelle H | title = Export and purification of a cytoplasmic dimeric protein by fusion to the maltose-binding protein of Escherichia coli | journal = European Journal of Biochemistry | volume = 193 | issue = 2 | pages = 325–30 | date = October 1990 | pmid = 2226455 | doi = 10.1111/j.1432-1033.1990.tb19341.x | doi-access = free }}</ref> When the recombinant MBP includes either a defective or no signal peptide the fusion protein remains within the bacterial [[cytoplasm]] from where it can be recovered by [[lysis|breaking open the cells]].

The fusion of proteins with MBP usually enhances their solubility and facilitates their proper folding so that the fusion proteins are most often bifunctional.<ref name="pmid3278900" /><ref>{{cite journal | vauthors = Kapust RB, Waugh DS | title = Escherichia coli maltose-binding protein is uncommonly effective at promoting the solubility of polypeptides to which it is fused | journal = Protein Science | volume = 8 | issue = 8 | pages = 1668–74 | date = August 1999 | pmid = 10452611 | pmc = 2144417 | doi = 10.1110/ps.8.8.1668 }}</ref> In addition, such fusions can facilitate the crystallisation of difficult proteins, e.g. membrane proteins. The crystallized protein can often have their structures solved by [[X-ray crystallography]] using [[molecular replacement]] on a known MBP structure.<ref>{{cite journal | vauthors = Waugh DS | title = Crystal structures of MBP fusion proteins | journal = Protein Science | volume = 25 | issue = 3 | pages = 559–71 | date = March 2016 | pmid = 26682969 | pmc = 4815407 | doi = 10.1002/pro.2863 }}</ref>

== See also ==
*[[Protein tag]]
*[[Fluorescent glucose biosensors]]
*[[Glutathione S-transferase]]

== References ==
{{reflist}}

== External links ==
*[http://www.bio.mtu.edu/campbell/purifica.htm N-Terminal Fusion of Target Protein to Maltose-Binding Protein] at [[Michigan Technological University]]
* {{MeshName|maltose-binding+protein}}
* [http://www.nature.com/nprot/journal/v2/n2/full/nprot.2007.50.html Generic protocol for the expression and purification of recombinant proteins in Escherichia coli using a combinatorial His6-maltose binding protein fusion tag]

[[Category:Proteins]]

Context-adaptive variable-length coding

2024-11-17T15:56:43Z

76.71.3.150: the example seems to be from this 1 source

{{1r|date=November 2024}}

'''Context-adaptive [[variable-length code|variable-length coding]]''' ('''CAVLC''') is a form of [[entropy coding]] used in [[H.264/MPEG-4 AVC]] video encoding. It is an inherently [[lossless compression]] technique, like almost all entropy-coders. In H.264/MPEG-4 AVC, it is used to encode residual, zig-zag order, blocks of transform coefficients. It is an alternative to [[context-adaptive binary arithmetic coding]] (CABAC). CAVLC requires considerably less processing to decode than CABAC, although it does not compress the data quite as effectively. CAVLC is supported in all H.264 profiles, unlike CABAC which is not supported in Baseline and Extended profiles.

CAVLC is used to encode residual, zig-zag ordered 4×4 (and 2×2) blocks of transform coefficients. CAVLC is designed to take advantage of several characteristics of quantized 4×4 blocks:

* After prediction, transformation and quantization, blocks are typically sparse (containing mostly zeros).
* The highest non-zero coefficients after zig-zag scan are often sequences of +/− 1. CAVLC signals the number of high-frequency +/−1 coefficients in a compact way.
* The number of non-zero coefficients in neighbouring blocks is correlated. The number of coefficients is encoded using a look-up table; the choice of look-up table depends on the number of non-zero coefficients in neighbouring blocks.
* The level (magnitude) of non-zero coefficients tends to be higher at the start of the reordered array (near the DC coefficient) and lower towards the higher frequencies. CAVLC takes advantage of this by adapting the choice of VLC look-up table for the "level" parameter depending on recently coded level magnitudes.

==Coded elements==

Parameters that required to be encoded and transmitted include the following table:

{| class="wikitable"
|-
!Parameters
!Description
|-
| Macroblock type
| Prediction method for each coded macroblock
|-
| Coded block pattern
| Indicates which blocks within a macroblock contain coded coefficients
|-
| Quantizer parameter reference frame
| Transmitted as a delta value from the previous value of QP
|-
| Reference frame index
| Identify reference frame(s) for inter prediction
|-
| Motion vector
| Transmitted as a difference (mvd) from predicted motion vector
|-
| Residual data
| Coefficient data for each 4×4 or 2×2 block
|}

==CAVLC examples==

{| class="wikitable floatright"
! Element
! Value
! Code
|-
| coeff_token
| TotalCoeffs=5, T1s=3
| 0000100
|-
| T1 sign (4)
| +
| 0
|-
| T1 sign (3)
| -
| 1
|-
| T1 sign (2)
| -
| 1
|-
| Level (1)
| +1 (use Level_VLC0)
| 1
|-
| Level (0)
| +3 (use Level_VLC1)
| 0010
|-
| TotalZeros
| 3
| 111
|-
| run_before(4)
| ZerosLeft=3; run_before=1
| 10
|-
| run_before(3)
| ZerosLeft=2; run_before=0
| 1
|-
| run_before(2)
| ZerosLeft=2; run_before=0
| 1
|-
| run_before(1)
| ZerosLeft=2; run_before=1
| 01
|-
| run_before(0)
| ZerosLeft=1; run_before=1
| No code required; last coefficient.
|}

{| class="wikitable floatright"
! Code
! Element
! Value
! Output array
|-
| 0000100
| coeff_token
| Total Coeffs=5, T1s=3
| Empty
|-
| 0
| T1 sign
| +
| 1
|-
| 1
| T1 sign
| -
| −1, 1
|-
| 1
| T1 sign
| -
| −1, −1, 1
|-
| 1
| Level
| +1
| 1, −1, −1, 1
|-
| 0010
| Level
| +3
| 3, 1, −1, −1, 1
|-
| 111
| TotalZeros
| 3
| 3, 1, −1, −1, 1
|-
| 10
| run_before
| 1
| 3, 1, −1, −1, 0, 1
|-
| 1
| run_before
| 0
| 3, 1, −1, −1, 0, 1
|-
| 1
| run_before
| 0
| 3, 1, −1, −1, 0, 1
|-
| 01
| run_before
| 1
| 3, 0, 1, −1, −1, 0, 1
|}

In all following examples, we assume that table Num-VLC0 is used to encode coeff_token.

[[File:4x4CAVLC.svg|center|x140px]]

0, 3, 0, 1, −1, −1, 0, 1, 0…
TotalCoeffs = 5 (indexed from highest frequency [4] to lowest frequency [0])

TotalZeros = 3

T1s = 3 (in fact there are 4 trailing ones but only 3 can be encoded as a "special case")

Encoding:

The transmitted bitstream for this block is 000010001110010111101101.

Decoding:
The output array is "built up" from the decoded values as shown below. Values added to the output array at each stage are underlined.

The decoder has inserted two zeros; however, TotalZeros is equal to 3 and so another 1 zero is inserted before the lowest coefficient, making the final output array: 0, 3, 0, 1, −1, −1, 0, 1

==See also==
* [[Advanced Video Coding#Features|H.264 (entropy coding)]]
* [[Data compression]]
* [[Lossless compression]]

== References ==

* {{Cite web |last=Richardson |first=Iain |date=August 28, 2011 |title=H.264 / AVC Context Adaptive Variable Length Coding |url=http://www.staroceans.org/e-book/vcodex/H264_cavlc_wp.pdf |access-date=17 November 2024 |publisher=Vcodex}}

[[Category:Entropy coding]]
[[Category:MPEG]]
[[Category:Video compression]]
{{comp-sci-stub}}

Assumpsit

2024-11-12T22:37:09Z

76.71.3.150: /* Emergence of assumpsit */ pct

{{Short description|Form of action at common law}}
{{Use dmy dates|date=April 2022}}
'''Assumpsit''' ("he has undertaken", from [[Latin]], ''assumere''),<ref name="EB 1911, p. 787">{{EB1911|inline=1|wstitle=Assumpsit |volume=2 |page=787}}</ref> or more fully, '''action in assumpsit''', was a [[form of action]] at [[common law]] used to enforce what are now called obligations arising in [[tort]] and [[contract]]; and in some common law jurisdictions, [[unjust enrichment]]. The origins of the action can be traced to the 14th century, when litigants seeking justice in the royal courts turned from the writs of covenant and debt to the [[trespass on the case]].<ref>{{Cite news|date=January 1918|title=The Modern Law of Assumpsit|work=West Virginia University|url=https://researchrepository.wvu.edu/cgi/viewcontent.cgi?article=6053&context=wvlr}}</ref>

== History ==

=== Fragmentation of actions for breach of agreement ===
In the early days of the English common law, agreements were enforced in local courts. Where one wished to enforce an agreement in the royal courts, it was necessary to fit one's claim within a [[form of action]]. In the 13th and 14th centuries the forms of action for the enforcement of agreements were covenant, debt, detinue, and account.<ref>See generally, [[John Baker (legal historian)|Sir John Baker]], ''An Introduction to English Legal Historically'' (4th ed, 2004); [[David Ibbetson|Professor David Ibbetson]], ''Historical Introduction to the Law of Obligations'' (2nd ed).</ref> These were all writs in the ''praecipe'' form, meaning that they commanded the defendant to perform an act: for example, to keep a promise; to yield up a sum of money or chattel unjustly withheld; or to render accounts.

These actions were subject to various limitations. For example, by the middle of the 14th century at the latest, it was necessary for a plaintiff in an action of covenant to have a deed.<ref>''Waltham Carrier Case'' (1321) Eyre of London</ref> In an action of debt ''sur contract'', a deed was not necessary, but a defendant was able to [[Wager of law|wage his law]] and the sum claimed had to be a sum certain fixed at the date of contract. Such rules could easily work hardship. What if a promisor (A) orally agreed to supply grain to a promisee (B), but failed to do so? In such a case, B would be unable to bring a writ of covenant due to the absence of a deed. B would instead bring debt ''sur contract'', bringing a number of transaction witnesses. But what if A elected wager of law and simply hired his eleven oath-helpers?

=== Emergence of assumpsit ===
Litigants began to turn from the ''praecipe'' writs of covenant and debt to the ''ostensurus quare'' writ of [[Trespass in English law|trespass]]. By the middle of the 14th century the royal courts were recognising that a writ of trespass would lie even without an allegation that the defendant had acted ''vi et armis contra pacem regis'' (with force and arms against the King's Peace).<ref>[[The Humber Ferryman's case|The Humber Ferryman's Case]] (1348) B&M 358</ref> This action became known as [[trespass on the case]].

To bring the claim within trespass on the case, the plaintiff would characterise the defendant's breach of agreement as a wrong. During the 15th century, the received learning was that an action on the case did not lie for mere inaction ("nonfeasance").<ref>''Wootton v Brygeslay'' (1400); ''Watkin's Case'' (1425)</ref> By the beginning of this 16th century, this was no longer the case. Provided a plaintiff could show that the defendant was guilty of misfeasance, deceit, or the plaintiff had made a pre-payment, the plaintiff could bring assumpsit for nonfeasance.

By the beginning of the 16th century, lawyers recognised a distinct species of action on the case known as assumpsit, which had become the typical phrase in the pleadings.<ref>[[A. W. B. Simpson|AWB Simpson]], ''A History of the Common Law of Contract'' at 199; [[John Baker (legal historian)|Sir John Baker]], ''An Introduction to English Legal History'' (4th ed, 2004) 330.</ref>

=== Assumpsit in lieu of debt ===
The question that arose in the 16th century was whether assumpsit could be brought in lieu of debt.<ref>See generally, Professor David Ibbetson, ''Historical Introduction to the Law of Obligations'' (2nd ed).</ref> For a plaintiff, assumpsit was the more desirable course: the defendant would not be able to elect to [[Wager of law|wage his law]] as he would in debt ''sur contract''.

In order to bring assumpsit, the plaintiff would plead that, the defendant being indebted to the plaintiff, the defendant had later promised to pay the debt. In short, the plaintiff would separate the existence of the debt (which generated an action of debt ''sur contract'') from a promise to pay the debt (which would generate an assumpsit for nonfeasance). This form of pleading gave rise to the name of the action: ''indebitatus assumpsit''.<ref>The Latin phrase means "being indebted, he promised," or, more literally, "he undertook" or "he assumed the duty [to pay]."</ref>

The practice of the [[Court of King's Bench (England)|King's Bench]] and the [[Court of Common Pleas (England)|Court of Common Pleas]] differed during the course of the 16th century. In the King's Bench, it was not necessary for the plaintiff to prove the subsequent promise. The Common Pleas disagreed. Matters came to a head in ''[[Slade's Case]]'' in 1602. The case effectively established that assumpsit could be used in lieu of debt: the law would imply a promise to pay the debt from the existence of the debt itself.<ref>{{cite web
| url=http://www.fordham.edu/halsall/basis/maitland-formsofaction.html
| title=The Forms of Action at Common Law
| accessdate=2007-07-06
| author=Maitland, F. W.
| authorlink=Frederic William Maitland
| year=1909
}}</ref>

''Slade's Case'' effectively put an end to the use of debt ''sur contract'', and with it wager of law. Of course, it was not possible to bring assumpsit where the proper action was debt ''sur obligation'' (that is, debt on a deed or bond).

=== Common counts ===
Claims in actions of assumpsit can be divided into:
* (a) common or ''indebitatus assumpsit'', brought usually on an implied promise, and
* (b) special or express assumpsit, founded on an express promise.<ref name="EB 1911, p. 787"/><ref>See also {{cite book |first=Lionel D |last=Smith |display-authors=etal |title=The Law of Restitution in Canada: Cases, Notes, and Materials |pages=72–75 |publisher=Emond Montgomery |year=2004 |isbn=1552391167 |url=https://books.google.com/books?id=CIvr-XmBRBwC&q=%22indebitatus+assumpsit%22&pg=PA72}}</ref>
Where a plaintiff brought assumpsit in lieu of debt ''sur contract'', it was necessary for the plaintiff to specify how the antecedent debt had arisen. It was insufficient for the plaintiff to merely allege that, being indebted, the defendant promised to pay. This gave rise to the "common counts": common ways of pleading how the debt arose. It is important to note that where assumpsit was brought in lieu of debt, the plaintiff's action was for a liquidated sum. In contrast, where a plaintiff brought special assumpsit, the action was for an unliquidated sum assessed by the civil jury.

Examples of the common counts include:
* For goods sold ("[[quantum valebant]]");
* For work done ("[[quantum meruit]]");
* For money lent;
* For money due on an account stated;
* For money laid out to the use of the defendant; and
* For [[Money had and received|money had and received to the defendant's use]].
By the 18th and 19th centuries, the action of assumpsit was used to enforce both contractual and [[quasi-contract]]ual claims. The recognition in ''Slade's Case'' that the law would import or imply a promise to pay the debt paved the way for other implications.
* In some cases, such as actions for a reasonable remuneration for services provided to the defendant at the defendant's request (a ''quantum meruit''), the implication might be a true reflection of reality. If so, in modern terms, this is simply an action in contract for breach of an implied term.
* In other cases, however, the implication of a promise to pay was wholly fictitious. For example, where A mistakenly paid money to B, A would bring an action for [[Money had and received|money had and received to the defendant's use]]. In such a case, the law would imply a promise by B to pay the debt. In modern terms, this is an action in [[English unjust enrichment law|unjust enrichment]]: B is enriched by the receipt of money at the expense of A in circumstances which are 'unjust' (viz., that A's intention to benefit B is vitiated by the mistake).

== Abolition of the forms of action ==
The ''Common Law Procedure Act 1852'' abolished the common law forms of action in [[England and Wales]]. Furthermore, assumpsit as a form of action became obsolete in the [[United Kingdom]] after the passing of the [[Judicature Acts]] of 1873 and 1875.<ref name="EB 1911, p. 787"/>

In the [[United States]], assumpsit, like the other forms of action, became obsolete in the [[United States federal courts|federal courts]] after the adoption of the ''[[Federal Rules of Civil Procedure]]'' in 1938. Thirty-five states have moved to rules similar to the FRCP (see [[Civil procedure in the United States]]), which have replaced the various forms of action with the [[civil action]]. However, many states continue to recognize assumpsit as a common law or [[Statute|statutory]] [[cause of action]] or allow the use of the old "common counts" as causes of action. For example, California has a special "common counts" cause of action form (to be attached to an optional form complaint) based directly on the old common counts that were pleaded in assumpsit.<ref>[http://www.courtinfo.ca.gov/forms/documents/pldc0012.pdf Form PLD-C-001(2), Cause of Action-Common Counts, Judicial Council of California (Rev. Jan. 1, 2009).]</ref>

== Modern significance ==
The traces of the law relating to assumpsit are still felt today, particularly in the law of [[contract]] and [[unjust enrichment]]. For example, [[Consideration in English law|consideration]] is only necessary in relation to [[simple contract]]s. Where a claimant brings an action in contract for non-performance of a promise contained in a deed, there is no need to show that the claimant supplied consideration for the promise. The reason for this is historical: where there was no deed, the correct action was assumpsit for nonfeasance; in the latter, in debt ''sur obligation''. These were two distinct forms of action with their own distinct procedural requirements.<ref>{{Cite news|title=THE LIMITATIONS OF THE ACTION OF ASSUMPSIT AS AFFECTING THE RIGHT OF ACTION OF THE BENEFICIARY.|work=University of Pennsylvania Carey Law School|url=https://scholarship.law.upenn.edu/cgi/viewcontent.cgi?article=6578&context=penn_law_review}}</ref>

In the [[English unjust enrichment law|law of unjust enrichment]], reference is still made to [[Money had and received|actions for money had and received]] and [[quantum meruit]]. The practice is often deprecated by English unjust enrichment scholars<ref>See Andrew Burrows, ''Law of Restitution'' (3rd ed, 2011); Graham Virgo, ''Principles of the Law of Restitution'' (3rd ed, 2015).</ref> but is frequently encountered in Australia.<ref>See, for example, {{cite AustLII|NSWCA|81|2016|litigants=Fistar v Riverwood Legion and Community Club Ltd |courtname=auto}}.</ref>

==References==
{{Reflist|30em}}

[[Category:Legal history of England]]
[[Category:Civil procedure]]
[[Category:English contract law]]

Trespass on the case

2024-11-12T22:32:53Z

76.71.3.150: /* Emergence of the writ of trespass */ wl

The [[writ]]s of '''trespass''' and '''trespass on the case''' are the two catchall [[tort]]s from [[English common law]], the former involving [[trespass]] against the person, the latter involving trespass against anything else which may be actionable. The writ is also known in modern times as '''action on the case''' and can be sought for any action that may be considered as a [[tort]] but is yet to be an established category.

== Emergence of the writ of trespass ==
Trespass and trespass on the case, or "case", began as personal remedies in the royal courts in London in the 13th century. These early forms of trespass reflected a wide range of wrongs.

In 1278, however, the [[Statute of Gloucester]] was passed. This limited actions in the royal courts to property damage worth above 40 shillings, maims, beatings or wounds. Soon after this Statute was passed, writs of trespass appeared in a stereotyped form alleging "force and arms", or "''[[vi et armis]]''". Trespass writs alleging force and arms became known simply as trespass.

Some of the cases brought in ''vi et armis'' form probably did not involve force and arms at all and could be regarded as [[Legal fiction|fictions]].<ref>Baker J.H., ''An Introduction to English Legal History'', pg 61.</ref>

An example is ''[[Rattlesdene v Grunestone]]'' in 1317<ref>printed in Y.B. 10 Edw. II, Selden Society vol. 54</ref> on the adulteration of wine with salt water. The form of the writ, stated however, that the defendants "with force and arms, namely with swords and bows and arrows, drew off a great part of the wine from the aforesaid tun and instead of the wine so drawn off they filled the tun with salt water so that all the aforesaid wine was destroyed".

== Emergence of the writ of trespass on the case ==
By the 1350s, writs of trespass could be litigated in the royal courts only if they alleged "force and arms". That was, however, largely a problem of procedure; some sections of the royal courts were more liberal than others in that respect. In particular, procedure under the [[Court of King's Bench (England)|King's Bench]] was less strict than procedure by writ in the [[Court of Common Pleas (England)|Court of Common Pleas]]. Several cases were brought by a procedure of Bill into the King's Bench which did not allege force and arms between the 1340s and 1360s. In the Humber Ferry Case (1348), a horse was lost while being ferried across the Humber, and no force of arms was alleged.

The turning point in the creation of "honest" writs of Case was ''Waldon v Mareschal'' (1369). It was alleged that the defendant had negligently treated the plaintiff's horse. The Common Pleas accepted that in such a situation, an allegation of force and arms in a writ would not be appropriate. By the 1390s, actions on the case were common.

==See also==
*''[[Pierson v. Post]]'', a Supreme Court of New York case from 1805 dealing with Trespass to case.
*''[[Keeble v Hickeringill]]''
*[[English tort law]]

==References==
{{Reflist}}

[[Category:Tort law]]
[[Category:Writs]]

Fischer–Hepp rearrangement

2024-11-12T17:02:36Z

76.71.3.150: MOS:ORDER

{{Short description|Organic reaction applied to aromatic nitroso and nitrosamine compounds}}
{{Reactionbox
| Name = Fischer-Hepp rearrangement
| Type = Rearrangement reaction
| NamedAfter = [[Otto Philipp Fischer|Otto Fischer]] Eduard Hepp
| Section3 = {{Reactionbox Identifiers
| RSC_ontology_id = 0000095
}}
}}

In [[organic chemistry]], the '''Fischer–Hepp rearrangement''' is a [[rearrangement reaction]] in which an [[aromatic]] N-[[nitroso]] ({{chem2|\sN\dO}}) or secondary [[nitrosamine]] ({{chem2|>N\sN\dO}}) converts to a carbon nitroso compound:<ref>{{Cite journal |last1=Fischer |first1=Otto |last2=Hepp |first2=Eduard |date=July–December 1886 |title=Zur Kenntniss der Nitrosamine |url= https://zenodo.org/record/1425449|journal=Berichte der Deutschen Chemischen Gesellschaft zu Berlin |language=en |volume=19 |issue=2 |pages=2991–2995 |doi=10.1002/cber.188601902297 |issn=0365-9496 |eissn=1099-0682 |s2cid=95280925 |id=[[Zenodo]] [https://zenodo.org/record/1425449 1425449]. [[Gallica]] [https://gallica.bnf.fr/ark:/12148/bpt6k907075/f473.item ark:/12148/bpt6k907075/f473.item] |hdl-access=free |hdl=2027/njp.32101044028619?urlappend=%3Bseq=1121}}</ref><ref>M B Smith, J March. ''March's Advanced Organic Chemistry'' (Wiley, 2001) ({{ISBN|0-471-58589-0}}) / {{Cite book |last=Michael B. |first=Smith |url=https://app.knovel.com/hotlink/pdf/id:kt011AYKO1/marchs-advanced-organic/aromatic-s-groups-cleaving |title=March's Advanced Organic Chemistry - Reactions, Mechanisms, and Structure |date=2013 |publisher=John Wiley & Sons, Inc. |isbn=978-0-470-46259-1 |edition=7th |location=Hoboken, New Jersey |page=639 |chapter=11.6.2.2 Groups Cleaving from Nitrogen; Reaction 11-29: Migration of the Nitroso Group: The Fischer–Hepp Rearrangement |lccn=2012027160}}</ref>

[[Image:Fischerhepp.png|center|400px|Fischer-Hepp rearrangement]]

This [[organic reaction]] was first described by the German chemist [[Otto Philipp Fischer]] (1852–1932) and
Eduard Hepp (June 11, 1851 – June 18, 1917) <ref>{{Cite book |last1=Pötsch |first1=Winfried R. |title=Lexikon bedeutender Chemiker |last2=Fischer |first2=Annelore |last3=Müller |first3=Wolfgang |date=1988–1989 |publisher=Verlag Harri Deutsch / VEB Bibliographisches Institut Leipzig |others=With the collaboration of Heinz Cassebaum |isbn=3-8171-1055-3 |location=Thun & Frankfurt |pages=148, 197}}</ref> in 1886, and is of importance because [[aromatic para substituent|para]]-[[nitroso|NO]] secondary [[aniline]]s cannot be prepared in a direct reaction.

The [[rearrangement reaction]] takes place by reacting the [[nitrosamine]] precursor with [[hydrochloric acid]]. The [[chemical yield]] is generally good under these conditions, but often much poorer if a different [[acid]] is used.<ref name=March20>{{cite book|pages=678–679|title=March's Organic Chemistry|edition=8th|first1=Michael B.|last1=Smith|publisher=Wiley|year=2020}}</ref> The exact [[reaction mechanism]] is unknown but the chloride counterion is likely not relevant, except in a competing decomposition reaction. There is evidence suggesting an [[intramolecular reaction]], similar to that seen in the [[Bamberger rearrangement]]. Nitrosation follows the classic patterns of [[electrophilic aromatic substitution]] (for example, a ''meta'' [[nitro compound|nitro]] group [[electrophilic aromatic directing groups|inhibits the reaction]]), although substitution ''ortho'' to the amine is virtually unknown. The final step, in which a proton eliminates from the [[Wheland intermediate]], appears to be [[rate-determining step|rate-limiting]], and the rearrangement is also suppressed in excessive (e.g. >10[[molarity|M]] [[sulfuric acid|sulfuric]]) acid.<ref>{{cite book|pages=115–125|title=Nitrosation|first=D. L. H.|last=Williams|publisher=Cambridge University|location=Cambridge, UK|year=1988|isbn=0-521-26796-X}}</ref>

==See also==
*[[Friedel–Crafts alkylation]]-like reactions:
**[[Hofmann-Martius rearrangement]]
**[[Fries rearrangement]]

==References==
<references />

==Sources==
*{{Cite web |last=Andraos |first=John |date=2000–2012 |title=Named Things in Chemical Industry |url=https://careerchem.com/NAMED/Industry.pdf |url-status=live |archive-url=https://web.archive.org/web/20230407175424/http://careerchem.com/NAMED/Industry.pdf |archive-date=2023-04-07 |access-date=2024-05-01 |website=Named Things in Chemistry & Physics}}

{{DEFAULTSORT:Fischer-Hepp Rearrangement}}
[[Category:Rearrangement reactions]]
[[Category:Name reactions]]

Wiki143:Ignore personal attacks

2024-11-07T17:05:23Z

76.71.3.150: "wikt:dialogue" is a more formal and correct spelling for this discussion sense of the word, while "wikt:dialog" is usually for computing

{{essay|WP:IPAT}}
{{nutshell|If someone attacks you personally, you should ignore it, rise above it, and continue to comment solely on relevant content.}}

It is unpleasant to be personally attacked or treated [[WP:CIVIL|uncivilly]], but it happens sometimes – whether because another user is abrasive, or because they're angry. [[WP:No personal attacks|Personal attacks]] often cause the person being attacked to feel angry or trod-on, and often they'll try to pursue some sort of remedy against the mistreatment. It is tempting to respond to a user who personally attacks you by defending yourself, attacking them back, reporting the user to a community noticeboard, or by leaving an official "warning" on the attacker's talk page. All of these things are usually unnecessary and serve only to escalate the conflict you're experiencing.

An angry, [[WP:No angry mastodons|heated conflict]] will rarely draw compromise, and frequently involves producing enormous quantities of [[WP:DRAMA|drama]]. Different people have different concepts of appropriate and civil dialogue, and this frequently causes unnecessary escalation of trivial misunderstandings (the conflict cycle). If at all possible, ignore and forgive the personal attack, and try to engage the other user in constructive dialogue focused on whatever issue you were discussing. [[WP:FOC|Focus on content]], respect Wikipedia's policies and guidelines, and look for ways to de-escalate tensions and conflict.

It is useful to apply the principle of "[[meatball:DefendEachOther|defend each other]]". That is, you should ignore people who attack you, but if you see them attacking somebody else, you can do the other person a favor and drop a quick (possibly private) reminder to be civil.

== See also ==
* [[WP:BATTLE|Wikipedia is not a battleground]]
* [[WP:IAD|Ignore all dramas]]
* [[Wikipedia:Two wrongs don't make a right|Two wrongs don't make a right]]
* [[meatball:ForgiveAndForget|ForgiveAndForget]] (Meatball wiki)
* [[meatball:ConflictCycle|ConflictCycle]] (Meatball wiki)
* [[meatball:DefendEachOther|DefendEachOther]] (Meatball wiki)
* [[WP:Shunning]]
* [[Social exclusion]]
* [[Agape]]