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21e755b2a6e34e88aaeaffb58393131f132cb3a7
during the 2014 heartbleed mass revocation event, where
during the 2014 heartbleed mass revocation event, where revocation rates rose from 1% to 11%, cloudflare estimated that the bandwidth that globalsign used to distribute crls could have cost 400,000 usd (equivalent to 510,000 usd in 2023).
wikipedia
1bc838a42efdad59b8b9cbdf0ecba0840f9ca494
failing-hard can introduce new denial-of-service attack vectors. for
failing-hard can introduce new denial-of-service attack vectors. for example, if clients expect ocsp stapling and fail-hard otherwise, a denial of service against ocsp responders is amplified to a denial of service against all services wishing to use those ocsp responses.
wikipedia
3e0a47a903eebd5b272a36d32371c5710fbc8d11
an attacker with the ability to present a
an attacker with the ability to present a compromised certificate likely also has the ability to prevent the client performing an online revocation status check; in this case, failing-soft effectively provides no protection at all. browsers have chosen this arm of the dilemma and preferred availability over security.
wikipedia
2c2159836222fe01f765d5cc700749a110d4e163
if revocation status is unavailable (which may be
if revocation status is unavailable (which may be benign or due to an attack), a client is faced with a dilemma when evaluating a certificate: it may fail-soft and assume that the certificate is still valid; or it may fail-hard and assume that the certificate has been revoked. this is a trade-off between security and a...
wikipedia
f3277cd5937157d4632901c04edf4350fb4d09ed
revocation statuses are not typically preserved and archived
revocation statuses are not typically preserved and archived for long beyond the certificate's expiry, making research into and auditing of revocation behaviours difficult. one proposal to solve this involves submitting 'postcertificates' to certificate transparency logs for each revocation, which would also allow revo...
wikipedia
7d518688a70115d8b31ac3da8cf311a1fddb645d
revocation may be initiated by a certificate holder
revocation may be initiated by a certificate holder (who, for example, may know that a private key has been compromised), who informs the ca. the ca then produces and distributes cryptographically authenticated attestations that the certificate has been revoked. the ca/b requirements also allow a ca to autonomously rev...
wikipedia
87307bd248ff311f8ff21e295f5ca0c62ef80183
revocation may not be necessary for certificates of
revocation may not be necessary for certificates of sufficiently short lifetime, roughly on the order of hours to days, which is comparable to the lifetime of an ocsp response. the associated frequent certificate issuance typically requires automation (e.g., the acme protocol) and may stress other infrastructural eleme...
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11885a98fa025566e25abf8d933be70760e81f26
certificate revocation is "an important tool" for dealing
certificate revocation is "an important tool" for dealing with attacks and accidental compromises. rfc 9325 places a normative requirement on tls implementations to have some means of distrusting certificates. without revocation, an attacker can use a compromised certificate to impersonate its owner until expiry.
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16dabca429a99e8e4a3cd12c8b22ba54edc6230a
chuat et al. (2020) call revocation "notoriously challenging".
chuat et al. (2020) call revocation "notoriously challenging". in 2022, rfc 9325 characterised certificate revocation as an important problem with "no complete and efficient solution". ocsp and ocsp stapling are recommended as the "foundation for a possible solution".
wikipedia
684cbe91cc5178db1b3ef4fcfc62a78c75575eab
the number of certificates in the web pki
the number of certificates in the web pki increased massively during the last portion of the 2010s, from 30 million in january 2017 to 434 million in january 2020. a significant factor in this growth is let's encrypt providing free domain validated certificates. the size of the potentially-revocable set of certificates...
wikipedia
f7626fc90d8662fab4776f08a7eee85ff3e6014c
despite web security being a priority for most
despite web security being a priority for most browsers, due to the latency and bandwidth requirements associated with ocsp and crls, browsers place limits on checking certificate status. in 2015, google chrome only actively checked extended validation certificates, no mobile browser performed any validity checks, and ...
wikipedia
7f3f65f42446da8131253ad7e689f4b0cefc03d0
the heartbleed vulnerability, which was disclosed in 2014,
the heartbleed vulnerability, which was disclosed in 2014, triggered a mass revocation of certificates, as their private keys may have been leaked. globalsign revoked over 50% of their issued certificates. startcom was criticised for issuing free certificates but then charging for revocation.
wikipedia
fce9fac95f998ce3acb0c5c9af1a1450c64ce3b2
due to the cost of revocation checks and
due to the cost of revocation checks and the availability impact from potentially-unreliable remote services, web browsers limit the revocation checks they will perform, and will fail soft where they do. certificate revocation lists are too bandwidth-costly for routine use, and the online certificate status protocol pr...
wikipedia
00711a34fe7911c03b608ca885b3c5d54c0f66b2
for distributing revocation information to clients, the timeliness
for distributing revocation information to clients, the timeliness of the discovery of revocation (and hence the window for an attacker to exploit a compromised certificate) trades off against resource usage in querying revocation statuses and privacy concerns. if revocation information is unavailable (either due to an...
wikipedia
7b5f5e16b28bb0be17f36c4532939e906499fc6e
in public key cryptography, a certificate may be
in public key cryptography, a certificate may be revoked before it expires, which signals that it is no longer valid. without revocation, an attacker could exploit such a compromised or misissued certificate until expiry. hence, revocation is an important part of a public key infrastructure. revocation is performed by ...
wikipedia
fa7eac9276019cf0ba5c701cda4686c15b55d51d
charles miller is a scottish retired footballer. he
charles miller is a scottish retired footballer. he started his career at rangers, and was voted the spfa young player of the year in 1995 during his time with the club. after spells with english premier league clubs leicester city and watford, miller joined dundee united in 2000 where he played for four seasons. mille...
wikipedia
005eb034de7da7ac0e6a8ddff3c12c8767aa23ec
miller won his sole cap for scotland in
miller won his sole cap for scotland in a 1–1 draw with poland in 2001. steven caldwell, kenny miller, barry nicholson, gavin rae, john o'neil and andy mclaren (the latter a childhood friend of miller from castlemilk) also made their scotland debuts in the same game. scotland manager craig brown stated that 'charlie mi...
wikipedia
47edb02e625921953be12f71a98630c69acce84e
it was reported on 12 november 2010 that
it was reported on 12 november 2010 that miller would spend the week training with scottish second division club ayr united. in february 2011, he signed for clyde until the end of the season. he was released at the end of the season, after only making 5 appearances. after retiring from professional football, he began o...
wikipedia
8b4350a381a643d4668a2d57bfd68d0950c1c72a
after leaving the roar, miller was linked with
after leaving the roar, miller was linked with a move to queensland rivals, north queensland fury fc and gold coast united. on 5 december 2009 he was a guest at a gold coast united fixture sparking rumors of a potential move. miller signed with gold coast on a short-term injury replacement contract. while in australia,...
wikipedia
61c373a81001785293bea7a3c733cddeeb7fb415
he was diagnosed with a hernia and underwent
he was diagnosed with a hernia and underwent surgery. miller returned to the first team on 17 january 2009 as a substitute against sydney fc coming on late in the game, and made the pass that set up sergio van dijk 's third goal of the match. on 5 december 2009, miller's contract with the roar was terminated by mutual ...
wikipedia
b431befba121d39a495f8a2431301a8ab0806872
on 31 july 2008, miller officially signed a
on 31 july 2008, miller officially signed a two-year deal with australian a-league club, brisbane roar. on 14 september, against perth glory, miller broke the a-league scoring record for the best start to a season by scoring four goals in the roar's opening four fixtures of the 2008–09 season.
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4e1a9212dda22a822aa31b5b1f18cd4f959a2335
on 9 february 2007, miller signed a contract
on 9 february 2007, miller signed a contract at the belgian team lierse s.k. on 20 april, he scored his first goals for lierse against germinal beerschot in their (ultimately unsuccessful) fight to stay in the first division. on 27 june he signed a three-year contract with lierse but was released less than a year later...
wikipedia
19b715457e12fde219382e3d9aecdc3194393a41
during his time at brann he went on
during his time at brann he went on trial at english championship club cardiff city, but was not offered a full deal. in early january 2007, miller began training with scottish first division club st johnstone to top up his fitness during the norwegian league's winter break. his contract with sk brann was terminated af...
wikipedia
b361b0b2ede9f668c9467171ed910117420b51da
in bergen, miller became one of the supporters'
in bergen, miller became one of the supporters' favourite players, due to his technique and passing ability. despite this, he was in and out of the team, according to manager mons ivar mjelde because of defensive considerations. he had early success with the club in the 2004 norwegian football cup final, a 4–1 win over...
wikipedia
ef4ed35769ee4ba90ac149644e56a34dee0e13bb
miller enjoyed a successful four-year spell at tannadice,
miller enjoyed a successful four-year spell at tannadice, becoming a firm favourite with the fans and making his international debut, but also losing two cup semi-finals to celtic (2000–01 scottish cup and 2002–03 scottish league cup). away from the pitch, an existing addiction to sports betting worsened, requiring him...
wikipedia
2a20b2c3d2c9128d432e46978fb401f03765ca8e
having fallen out of favour at ibrox with
having fallen out of favour at ibrox with the emerging barry ferguson being preferred in midfield, miller was loaned to leicester city towards the end of the 1998–99 season (having played enough matches for rangers to receive a fourth league winner's medal) before joining watford for £450,000 in october 1999. watford w...
wikipedia
f92ecef7a1b896b2a4634fea0ff04e1074b553e5
however, a lifestyle of parties and an unhealthy
however, a lifestyle of parties and an unhealthy diet (with both his old castlemilk pals and others such as teammate paul gascoigne 's entourage) accompanied this early success, even after he made attempts to start afresh by moving with his partner to rutherglen where their daughter was born in 1994, and his career app...
wikipedia
4af58bf1668ccde0bdd8c8ee98578d6d75c44f5a
miller made his senior debut in 1993 aged
miller made his senior debut in 1993 aged just 17, and showed he was talented enough to make an impression in the nine-in-a-row team under walter smith, winning three scottish premier division titles between 1995 and 1997 (providing the cross for brian laudrup to score the championship-clinching goal in the latter), as...
wikipedia
fb5fb49762fb2488b51037739ebd1f93c2cda991
miller was born in glasgow and raised in
miller was born in glasgow and raised in the castlemilk district of the city; he was brought up by his mother and has never met his father. he attended castlemilk high school before leaving early to join the staff at rangers, having been on a youth contract with the club since the age of 11. he had been introduced to f...
wikipedia
3d16ba0246e32d5b90b32bf765a63f26be459037
miller played for norwegian club sk brann from
miller played for norwegian club sk brann from 2004 to 2006 and won the norwegian cup with the club in 2004. after spells in belgium and australia, he returned to scotland in 2011 when he joined clyde.
wikipedia
f1188c407798f21603c0b7dd30a1e34d1660d9b0
charles miller (born 18 march 1976) is a
charles miller (born 18 march 1976) is a scottish retired footballer. he started his career at rangers, and was voted the spfa young player of the year in 1995 during his time with the club. after spells with english premier league clubs leicester city and watford, miller joined dundee united in 2000 where he played fo...
wikipedia
a7a56817064074aff9aa3754a9c50111037e85b2
cycloamyloses are cyclic α-1,4 linked glucans comprising dozens
cycloamyloses are cyclic α-1,4 linked glucans comprising dozens or hundreds of glucose units. chemically they are similar to the much smaller cyclodextrins, which are typically composed of 6, 7 or 8 glucose units.
wikipedia
7bf587514df5fa3e9e59b535504c24037beee0bc
cycloamyloses contain cavities in the helices which are
cycloamyloses contain cavities in the helices which are capable of accommodating guest molecules, which suggested applications in chemical technologies. cycloamylose is used in artificial chaperone technology for the refolding of denatured proteins. cycloglucans have physicochemical properties that make them useful in ...
wikipedia
3e5d4978c8b2935fa22d21300b4ce69dcb16f3eb
while the structures of cyclodextrins are planar circles,
while the structures of cyclodextrins are planar circles, the structure of cycloamyloses with 10 to 14 glucose units were determined to be circular with strain-induced band-flips and kinks. in contrast the structure of a larger cycloamylose with 26 glucose units was determined to comprise two short left-handed v-amylos...
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9ea10d38ccca549eca7fd9d8b7624e33d0f18de9
upon incubation of d-enzyme with high molecular weight
upon incubation of d-enzyme with high molecular weight amylose, a product was obtained with decreased ability to form a blue complex with iodine, without reducing or non-reducing ends, and resistant to hydrolysis by glucoamylase (an exoamylase). takaha and smith deduced that the product was a cyclic polymer, which they...
wikipedia
9ff33a18a8d13b73a5babe5031ba29fe44890e30
cycloamyloses were discovered as a result of studies
cycloamyloses were discovered as a result of studies of the function of 4-α-glucanotransferase, also known as disproportionating enzyme or d-enzyme (ec 2.4.1.25) isolated from potato.
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eadaa7d1476a58d83a1f2b994e8de575f3f5d243
cycloamyloses are cyclic α-1,4 linked glucans comprising dozens
cycloamyloses are cyclic α-1,4 linked glucans comprising dozens or hundreds of glucose units. chemically they are similar to the much smaller cyclodextrins, which are typically composed of 6, 7 or 8 glucose units.
wikipedia
3458a424f64d2bb78a01c61da475b73305068eee
in chemistry and biochemistry, the henderson–hasselbalch equation relates
in chemistry and biochemistry, the henderson–hasselbalch equation relates the ph of a chemical solution of a weak acid to the numerical value of the acid dissociation constant, ka, of acid and the ratio of the concentrations, [ base ] [ acid ] of the acid and its conjugate base in an equilibrium. for example, the acid ...
wikipedia
ddc61fe8adf2a367ced8d7aec04d5ca3a70a023a
in 1909 søren peter lauritz sørensen introduced the
in 1909 søren peter lauritz sørensen introduced the ph terminology, which allowed karl albert hasselbalch to re-express henderson's equation in logarithmic terms, resulting in the henderson–hasselbalch equation.
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f74c223860fb8fde35629db7e393e11356682ed4
c o 2 (g) {\displaystyle \mathrm {co_{2}(g)} }
c o 2 (g) {\displaystyle \mathrm {co_{2}(g)} } represents the carbon dioxide liberated as gas. in this equation, which is widely used in biochemistry, k m {\displaystyle k^{m}} is a mixed equilibrium constant relating to both chemical and solubility equilibria. it can be expressed as
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17d13402b26ad8645314ff472d285d4e71206c2c
where h c o 3 − {\displaystyle \mathrm
where h c o 3 − {\displaystyle \mathrm {hco_{3}^{-}} } is the bicarbonate ion and h 2 c o 3 {\displaystyle \mathrm {h_{2}co_{3}} } is carbonic acid. however, the solubility of carbonic acid in water may be exceeded. when this happens carbon dioxide gas is liberated and the following equation may be used instead.
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1c8b899776220457bd482101e52416c2387e520d
the value of p k w {\displaystyle \mathrm
the value of p k w {\displaystyle \mathrm {pk_{w}} } is ca. 14 at 25°c. this approximation can be used when the correct value is not known. thus, the henderson–hasselbalch equation can be used, without modification, for bases.
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b0e4753fdb28938cfb13b8e0b14e1720f103b7ad
is a product of a quotient of concentrations
is a product of a quotient of concentrations {\displaystyle {\frac {}{}}} and a quotient, Γ {\displaystyle \gamma }, of activity coefficients γ h + γ a − γ h a {\displaystyle {\frac {\gamma _{{\ce {h+}}}\gamma _{{\ce {a^-}}}}{\gamma _{ha}}}}.in these expressions, the quantities in square brackets signify the concentrat...
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67e2c5968a61c035aa285f77d5033ad46eba7351
assumption 2. the self-ionization of water can be
assumption 2. the self-ionization of water can be ignored.this assumption is not, strictly speaking, valid with ph values close to 7, half the value of pk, the constant for self-ionization of water. in this case the mass-balance equation for hydrogen should be extended to take account of the self-ionization of water.
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d498adf65add95550bb0c157a3671de5bfc1a473
c is the analytical concentration of the acid
c is the analytical concentration of the acid and c is the concentration the hydrogen ion that has been added to the solution. the self-dissociation of water is ignored. a quantity in square brackets,, represents the concentration of the chemical substance x. it is understood that the symbol h stands for the hydrated h...
wikipedia
8bb48ed52358a1e57b1a666b173975b3eb1de120
a simple buffer solution consists of a solution
a simple buffer solution consists of a solution of an acid and a salt of the conjugate base of the acid. for example, the acid may be acetic acid and the salt may be sodium acetate.the henderson–hasselbalch equation relates the ph of a solution containing a mixture of the two components to the acid dissociation constan...
wikipedia
2d922ff9394ff0c74f80de897938429c3848ad84
relates the ph of a chemical solution of
relates the ph of a chemical solution of a weak acid to the numerical value of the acid dissociation constant, k, of acid and the ratio of the concentrations, {\displaystyle {\frac {}{}}} of the acid and its conjugate base in an equilibrium.
wikipedia
29455442fd57a39a1912d832fc18de7e8319a64a
cobalt-precorrin-7 (c15)-methyltransferase (decarboxylating) (ec 2.1.1.196, cbit) is an
cobalt-precorrin-7 (c15)-methyltransferase (decarboxylating) (ec 2.1.1.196, cbit) is an enzyme with systematic name s-adenosyl-l-methionine:precorrin-7 c15-methyltransferase (c12-decarboxylating). this enzyme catalyses the following chemical reaction this enzyme catalyses both methylation at c-15 and decarboxylation of...
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dc6740caeab22e17f036b0322a5b37c6dff796a7
this enzyme catalyses both methylation at c-15 and
this enzyme catalyses both methylation at c-15 and decarboxylation of the c-12 acetate side chain of cobalt-precorrin-7 in the anaerobic pathway of adenosylcobalamin biosynthesis in bacteria such as salmonella typhimurium, bacillus megaterium, and propionibacterium freudenreichii subsp. shermanii.
wikipedia
a7ace676894ad396557adc3631542d2111befa48
cobalt-precorrin-7 (c)-methyltransferase (decarboxylating) (ec 2.1.1.196, cbit) is an
cobalt-precorrin-7 (c)-methyltransferase (decarboxylating) (ec 2.1.1.196, cbit) is an enzyme with systematic name s-adenosyl-l-methionine:precorrin-7 c -methyltransferase (c -decarboxylating). this enzyme catalyses the following chemical reaction
wikipedia
2613b973c6c99ef3c268c21fad6a93b817818d23
in geometry, a cevian is a line segment
in geometry, a cevian is a line segment which joins a vertex of a triangle to a point on the opposite side of the triangle. medians and angle bisectors are special cases of cevians. the name "cevian" comes from the italian mathematician giovanni ceva, who proved a well-known theorem about cevians which also bears his n...
wikipedia
eee81b5253e4270552d435cb3d4bf4cf514e6744
if from each vertex of a triangle two
if from each vertex of a triangle two cevians are drawn so as to trisect the angle (divide it into three equal angles), then the six cevians intersect in pairs to form an equilateral triangle, called the morley triangle.
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2613b973c6c99ef3c268c21fad6a93b817818d23
in geometry, a cevian is a line segment
in geometry, a cevian is a line segment which joins a vertex of a triangle to a point on the opposite side of the triangle. medians and angle bisectors are special cases of cevians. the name "cevian" comes from the italian mathematician giovanni ceva, who proved a well-known theorem about cevians which also bears his n...
wikipedia
8e1d07336e21c07ce675fcba465c0f2b78758424
hfim, acronym for high-frequency-impulse-measurement, is a type of
hfim, acronym for high-frequency-impulse-measurement, is a type of measurement technique in acoustics, where structure-borne sound signals are detected and processed with certain emphasis on short-lived signals as they are indicative for crack formation in a solid body, mostly steel. the basic idea is to use mathematic...
wikipedia
dfcef3c5f0924135af24f97184c6a3b569f26a71
high-frequency-impulse measurement is an algorithm for obtaining frequency
high-frequency-impulse measurement is an algorithm for obtaining frequency information of any structure- or air-borne sound source on the basis of discrete signal transformations. this is mostly done using to quantify the distribution of the energy content of a sound signal in frequency space. on the software side, the...
wikipedia
8e1d07336e21c07ce675fcba465c0f2b78758424
hfim, acronym for high-frequency-impulse-measurement, is a type of
hfim, acronym for high-frequency-impulse-measurement, is a type of measurement technique in acoustics, where structure-borne sound signals are detected and processed with certain emphasis on short-lived signals as they are indicative for crack formation in a solid body, mostly steel. the basic idea is to use mathematic...
wikipedia
33e673c681d1858fe1d5ab857af11ef2dd1c5ead
in group theory, cayley's theorem, named in honour
in group theory, cayley's theorem, named in honour of arthur cayley, states that every group g is isomorphic to a subgroup of a symmetric group. more specifically, g is isomorphic to a subgroup of the symmetric group sym ⁡ whose elements are the permutations of the underlying set of g.
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af81e000bebfd1466d01123219c7b8144065f9ba
the map g → sym ⁡ sending each
the map g → sym ⁡ sending each element g to ℓ g is an injective homomorphism, so it defines an isomorphism from g onto a subgroup of sym ⁡ . the homomorphism g → sym ⁡ can also be understood as arising from the left translation action of g on the underlying set g. when g is finite, sym ⁡ is finite too. the proof of cay...
wikipedia
1077bbb65ea83b1629e3b5c15b07d5ac5093aafb
theorem: let g be a group, and let
theorem: let g be a group, and let h be a subgroup.let g / h {\displaystyle g/h} be the set of left cosets of h in g.let n be the normal core of h in g, defined to be the intersection of the conjugates of h in g. then the quotient group g / n {\displaystyle g/n} is isomorphic to a subgroup of sym (g / h) {\displaystyle...
wikipedia
26452c253da3cc150c80f3921ed4418e2cf222ae
z 4 = { 0, 1, 2, 3
z 4 = { 0, 1, 2, 3 } {\displaystyle \mathbb {z} _{4}=\{0,1,2,3\}} with addition modulo 4; the elements correspond to e, (1234), (13)(24), (1432).
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f6a268a3584c38152c3feb674bf74e2c26e595a7
z 3 = { 0, 1, 2 }
z 3 = { 0, 1, 2 } {\displaystyle \mathbb {z} _{3}=\{0,1,2\}} with addition modulo 3; group element 0 corresponds to the identity permutation e, group element 1 to permutation (123), and group element 2 to permutation (132). e.g. 1 + 1 = 2 corresponds to (123)(123) = (132).
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9909cad9aeff3c5fa643c64a19a040eb261bd710
z 2 = { 0, 1 } {\displaystyle
z 2 = { 0, 1 } {\displaystyle \mathbb {z} _{2}=\{0,1\}} with addition modulo 2; group element 0 corresponds to the identity permutation e, group element 1 to permutation (12) (see cycle notation). e.g. 0 +1 = 1 and 1+1 = 0, so 1 ↦ 0 {\textstyle 1\mapsto 0} and 0 ↦ 1, {\textstyle 0\mapsto 1,} as they would under a permu...
wikipedia
6599cec6e54f756e37936557e4a605cce8257b6c
the identity element of the group corresponds to
the identity element of the group corresponds to the identity permutation. all other group elements correspond to derangements: permutations that do not leave any element unchanged. since this also applies for powers of a group element, lower than the order of that element, each element corresponds to a permutation tha...
wikipedia
f1adc226bcad51c7afbfe5a27841582df8ab00f0
the representation is faithful if ϕ {\displaystyle \phi
the representation is faithful if ϕ {\displaystyle \phi } is injective, that is, if the kernel of ϕ {\displaystyle \phi } is trivial. suppose g ∈ ker ϕ {\displaystyle g\in \ker \phi }. then, g = g e = g ⋅ e = e {\displaystyle g=ge=g\cdot e=e}. thus, ker ϕ {\displaystyle \ker \phi } is trivial. the result follows by use...
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6800809b10fd2ef3b7fd0e297807718eb9786fc9
an alternative setting uses the language of group
an alternative setting uses the language of group actions. we consider the group g {\displaystyle g} as acting on itself by left multiplication, i.e. g ⋅ x = g x {\displaystyle g\cdot x=gx}, which has a permutation representation, say ϕ: g → s y m (g) {\displaystyle \phi:g\to \mathrm {sym} (g)}.
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58e298bbeaa37ea8350e9cfc288a891848a73509
the homomorphism t is injective since t (g)
the homomorphism t is injective since t (g) = id (the identity element of sym(g)) implies that g ∗ x = x for all x in g, and taking x to be the identity element e of g yields g = g ∗ e = e, i.e. the kernel is trivial. alternatively, t is also injective since g ∗ x = g ′ ∗ x implies that g = g ′ (because every group is ...
wikipedia
bf9790de675cc2f2e2d3602796785471cf7e0f0d
the set k = { f : g
the set k = { f : g ∈ g } is a subgroup of sym(g) that is isomorphic to g. the fastest way to establish this is to consider the function t : g → sym(g) with t (g) = f for every g in g. t is a group homomorphism because (using · to denote composition in sym(g)):
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c6d5165a1f83d666b8eec534e749dcfc9ea07805
if g is any element of a group
if g is any element of a group g with operation ∗, consider the function f : g → g, defined by f (x) = g ∗ x. by the existence of inverses, this function has also an inverse, f g − 1 {\displaystyle f_{g^{-1}}}. so multiplication by g acts as a bijective function. thus, f is a permutation of g, and so is a member of sym...
wikipedia
baaf4c3101d901787bd26cf05d73f2c6bf8c54ab
a permutation of a set a is a
a permutation of a set a is a bijective function from a to a. the set of all permutations of a forms a group under function composition, called the symmetric group on a, and written as sym (a) {\displaystyle \operatorname {sym} (a)}. in particular, taking a to be the underlying set of a group g produces a symmetric gro...
wikipedia
98f84cb0ff1d0d89ccf86ab617d77eae63a55e9c
although burnside attributes the theorem to jordan, eric
although burnside attributes the theorem to jordan, eric nummela nonetheless argues that the standard name — "cayley's theorem" — is in fact appropriate. cayley, in his original 1854 paper, showed that the correspondence in the theorem is one-to-one, but he failed to explicitly show it was a homomorphism (and thus an e...
wikipedia
770013c0cfceaf7d2ffa64a66cf1ca8faddcb76d
while it seems elementary enough, at the time
while it seems elementary enough, at the time the modern definitions did not exist, and when cayley introduced what are now called groups it was not immediately clear that this was equivalent to the previously known groups, which are now called permutation groups. cayley's theorem unifies the two.
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a5af170e80865a6ff1783c58cdabb99365117549
when g is finite, sym (g) {\displaystyle \operatorname
when g is finite, sym (g) {\displaystyle \operatorname {sym} (g)} is finite too. the proof of cayley's theorem in this case shows that if g is a finite group of order n, then g is isomorphic to a subgroup of the standard symmetric group s n {\displaystyle s_{n}}. but g might also be isomorphic to a subgroup of a smalle...
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3d77eb7c246ebc9aa00b89a4ef36c97bad5c75f6
in group theory, cayley's theorem, named in honour
in group theory, cayley's theorem, named in honour of arthur cayley, states that every group g is isomorphic to a subgroup of a symmetric group. more specifically, g is isomorphic to a subgroup of the symmetric group sym (g) {\displaystyle \operatorname {sym} (g)} whose elements are the permutations of the underlying s...
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f768e6ebb70bf76732614855a4218b0f5f41177b
delbert harold mcnamara, ph.d. was an american astronomer
delbert harold mcnamara, ph.d. was an american astronomer at brigham young university and an internationally recognized authority in intrinsic variable and eclipsing binary stars. mcnamara received his ph.d. from the university of california at berkeley in 1950. his dissertation was entitled "a two color photometric st...
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delbert harold mcnamara, ph.d. was an american astronomer
letters. other rewards and recognition include the karl g. maeser research award in 1966, the fourth distinguished annual faculty lecture from brigham young university in 1967 and the wesley p. lloyd memorial award in 1982-83. mcnamara served in the united states navy during world war ii (1943–1946) and retired as a l...
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in 2000 mcnamara received the george van biesbroeck
in 2000 mcnamara received the george van biesbroeck prize by the american astronomical society for "long-term extraordinary or unselfish service to astronomy". he was honored in 2010 with the distinguished service award by the utah academy of sciences, arts & letters. other rewards and recognition include the karl g. m...
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cffe4cc02938571319cd5955780f74c41d050b74
from 1968 to 1991, mcnamara was editor of
from 1968 to 1991, mcnamara was editor of the publications of the astronomical society of the pacific. in 1987 he founded the conference series, which has grown to become one of the community's leading publishers of conference proceedings. mcnamara was also a member of the board of directors of the astronomical society...
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132b09706b196efd36d9ef43827ef0aed0b0f930
mcnamara was a recipient of the lick observatory
mcnamara was a recipient of the lick observatory fellowship while a graduate student at berkeley. he was a guest investigator at the mcdonald observatory in texas, guest investigator at the mount wilson and mount palomar observatories in california, guest investigator at the cerro tololo inter-american observatory in c...
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24a50206576766d6110bfeb5072171f16335e405
mcnamara received his ph.d. from the university of
mcnamara received his ph.d. from the university of california at berkeley in 1950. his dissertation was entitled "a two color photometric study of the eclipsing variable, yz cassiopeia". following his ph.d. he spent five years teaching and researching with the renown professor otto struve. in 1955, he joined brigham yo...
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bd78e7d4d2646b2bad2d4ae467a758bd70b17d64
delbert harold mcnamara, ph.d. (june 28, 1923 -
delbert harold mcnamara, ph.d. (june 28, 1923 - january 9, 2014) was an american astronomer at brigham young university and an internationally recognized authority in intrinsic variable and eclipsing binary stars.
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in enzymology, a cobalt-factor ii c20-methyltransferase (ec 2.1.1.151)
in enzymology, a cobalt-factor ii c20-methyltransferase (ec 2.1.1.151) is an enzyme that catalyzes the chemical reaction the two substrates of this enzyme are s-adenosyl methionine and cobalt-factor ii; its two products are s-adenosylhomocysteine and cobalt-factor iii. this enzyme belongs to the family of transferases,...
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26f723a70735ee5cd97893393c2b5cf95cdf40eb
this enzyme belongs to the family of transferases,
this enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. the systematic name of this enzyme class is s-adenosyl-l-methionine:cobalt-factor-ii c20-methyltransferase. this enzyme is also called cbil. this enzyme is part of the biosynthetic pathway to cobalami...
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8b29bb26c028b75785be3834e591257cfff8e7cc
cherie piper is a canadian former ice hockey
cherie piper is a canadian former ice hockey player residing in markham, ontario. she was a member of the canadian national women's hockey team and played for the brampton thunder of the canadian women's hockey league (cwhl). piper has won three olympic gold medals with the canadian national team in 2002, 2006 and 2010...
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cd3f8b1cb144fc28ef3cc260d58e864c73c41ea3
piper was born june 29, 1981, in toronto,
piper was born june 29, 1981, in toronto, ontario, the third child of alan and christine piper. she has two older brothers, michael and stephen, and followed her brothers in taking up the sport. she was educated in the toronto suburb of scarborough. her middle school was henry kelsey senior public school and her elemen...
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d302987d89acf08a2b193996841703859fc44a34
a knee injury in her senior year at
a knee injury in her senior year at dartmouth forced her off of the national team for over a year and caused her to miss the 2007 world championships. she rejoined the team in time for the 2008 tournament where she won her second silver medal. she was cut from the 2009 team, but gained a spot on the 2010 olympic team, ...
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68a39b68e78e25c7bf7e627743b0a2e8f592f841
she played four seasons at dartmouth college between
she played four seasons at dartmouth college between 2002 and 2007, scoring 60 goals and 165 assists in 99 games for the big green. she missed the end of the 2003–04 season to play with the canadian national team at the 2004 women's world ice hockey championships where she won a gold medal. piper was named a finalist f...
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b2ff0ceeeef0010619485037c132e536d855473f
she competed for canada's under 22 team from
she competed for canada's under 22 team from 1999 to 2001. in 1999, she competed for ontario in the canada winter games. during the 2000–01 nwhl season, cherie piper played with the beatrice aeros and finished seventh in league scoring with 37 points. piper was a member of the under-22 team in 2002 when she was named t...
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48ad793f5108c09367b564367c161b630b62ff8a
cherie piper (born june 29, 1981) is a
cherie piper (born june 29, 1981) is a canadian former ice hockey player residing in markham, ontario. she was a member of the canadian national women's hockey team and played for the brampton thunder of the canadian women's hockey league (cwhl). piper has won three olympic gold medals with the canadian national team i...
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9c0b1ced7d059bbfef908388d88606942922312d
the collective–amoeboid transition (cmt) is a process by
the collective–amoeboid transition (cmt) is a process by which collective multicellular groups dissociate into amoeboid single cells following the down-regulation of integrins. cmts contrast with epithelial–mesenchymal transitions (emt) which occur following a loss of e-cadherin. like emts, cats are involved in the inv...
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f776c7681515276eb7d4c90f825e214542705309
the collective–amoeboid transition (cmt) is a process by
the collective–amoeboid transition (cmt) is a process by which collective multicellular groups dissociate into amoeboid single cells following the down-regulation of integrins. cmts contrast with epithelial–mesenchymal transitions (emt) which occur following a loss of e-cadherin. like emts, cats are involved in the inv...
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4826ede29385fee92689af00bcb1bdd04251c031
cabot public schools is a public school district
cabot public schools is a public school district system in northern lonoke county, arkansas, usa. it serves 10,292 students in grades k-12 across 17 campuses. this district includes students living in cabot, ward, and austin. it is accredited by the arkansas department of education. the cabot public school board is mad...
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68adbe8ef78c1e7c09218ae6a48948ea8d0187f1
in 2017 the cabot school district received the
in 2017 the cabot school district received the "be the voice award" from the american foundation for suicide prevention. the cabot school district is also the first school district in arkansas to receive the arkansas purple star school award on all of their campuses.
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8852cda022bf928517535cde0c42607f00593e14
all teachers working full time in this district
all teachers working full time in this district are certified. the average student to teacher ratio is 16:1. the average salary for teachers in this district is $61,816. along with teachers this district also employs nurses, psychologists, social workers, law enforcement officers, and security guards.
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0f743864232ded3d1a9eaad32ede330d4b9dc66d
there are 10,292 students that attend the cabot
there are 10,292 students that attend the cabot school district. 86% of the student population is white. six percent of the students are hispanic and three percent are black. two percent of students are asian. one percent of the students attending this school are english learners. 20% of students are from low income fa...
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cf86048fdfb3ad0babd90f34b7bde81a8b5accb4
the cabot public school board is made up
the cabot public school board is made up of seven members. all of the educators in this district are certified. the graduation rate in the district is 91%. the district has expansive technology resources for students with thousands of devices across the campuses. it is also the only school district in arkansas to win t...
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7fddd758894fd9ac9fbf58c1a2169b0c3525a777
cabot public schools is a public school district
cabot public schools is a public school district system in northern lonoke county, arkansas, usa. it serves 10,292 students in grades k-12 across 17 campuses. this district includes students living in cabot, ward, and austin. it is accredited by the arkansas department of education.
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ab9b7479baee8592ce36b42012a34ddc7cca5ff9
caldiero is a comune (municipality) in the province
caldiero is a comune (municipality) in the province of verona in the italian region veneto, located about 90 kilometres (56 mi) west of venice and about 15 kilometres (9 mi) east of verona. caldiero borders the following municipalities: belfiore, colognola ai colli, lavagno, san martino buon albergo, and zevio.
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several battles were fought in the vicinity of
several battles were fought in the vicinity of caldiero during the french revolutionary wars and napoleonic wars. these actions occurred on 12 november 1796, on 29 – 31 october 1805, on 29 – 30 april 1809, and on 15 november 1813. all the battles were fought between france and austria. in 1796, the austrians repelled a...
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9e0f7a2d706ee1183881906514b4dfe0060b3d50
caldiero was known in ancient roman times as
caldiero was known in ancient roman times as calidarium, stemming from its thermal baths. later it was held by the bishops of verona who, in 1206, sold it to the commune. in 1233 ezzelino iii da romano destroyed the castle. later caldiero was held by the scaligers, the nogarola counts, the visconti and then by the repu...
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27e0502ecd0b49913f40069905f4c7df62fbd619
caldiero is a comune (municipality) in the province
caldiero is a comune (municipality) in the province of verona in the italian region veneto, located about 90 kilometres (56 mi) west of venice and about 15 kilometres (9 mi) east of verona.
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