id
stringlengths
40
40
title
stringlengths
15
120
text
stringlengths
41
3.14k
source
stringclasses
2 values
cc233c23b652fd68207c1eca8d2920a729c53856
schadt has appeared on cnn, cnbc, bbc, bloomberg
schadt has appeared on cnn, cnbc, bbc, bloomberg radio, and bloomberg tv. he and his scientific projects have been profiled in the new york times, esquire magazine, bloomberg businessweek, among others, and several scientific trade publications. the huffington post published a commentary by schadt, calling on scientist...
wikipedia
c9607d6f4609bbeac4b7f5b4a9b1bb2fe457922d
schadt founded sema4, "a patient-centered health intelligence company
schadt founded sema4, "a patient-centered health intelligence company dedicated to advancing healthcare through data-driven insights," in june 2017. the company uses centrellis™, their health analytics platform, to build predictive models of human health and generate personalized medicine insights. sema4, which was nam...
wikipedia
eee198921d4dd975c55bc8b1c34fd461ed189622
in may 2014, schadt and his team announced
in may 2014, schadt and his team announced the resilience project in collaboration with sage bionetworks. the project intended to perform genotyping on as many as 1 million people to find protective biological mechanisms that prevent disease-causing genetic mutations from becoming active. participants were to be health...
wikipedia
d689d668c615d11650162915a5774a213264dd8c
schadt's team was cited as the reason the
schadt's team was cited as the reason the icahn school of medicine at mount sinai was named #5 of the top 10 most innovative organizations in big data by fast company in a 2014 ranking. according to the article, "the new york city hospital is bringing on top silicon valley talent to build a facility that will map patie...
wikipedia
91df5d9a56311982ccdef1cc500dc2de065fef88
in 2013, schadt and his team were awarded
in 2013, schadt and his team were awarded a grant from the national institutes of health to study biological networks in alzheimer's disease. they also published a paper in cell reporting that a network of genes linked to inflammatory response plays a role in late-onset alzheimer's disease. also that year, schadt joine...
wikipedia
d3f6e655a22c0cb31162bdbfa10f25e0b5cc5d90
in 2011, schadt joined the mount sinai school
in 2011, schadt joined the mount sinai school of medicine in new york, where he founded the new icahn institute for genomics and multiscale biology and became chair of the department of genetics and genomics sciences. the new institute was launched with $100 million for the first five years and is co-directed by andrew...
wikipedia
7560fa071f5c56aca72588106a338786e6468e96
also in 2009, schadt joined dna sequencing company
also in 2009, schadt joined dna sequencing company pacific biosciences as the chief scientific officer. during his time there, schadt demonstrated the application of smrt sequencing technology for various applications, including to sequence bacterial genomes of public health concern to provide real-time information abo...
wikipedia
9c8cc4200bc35687d84b37fc2d179bc067ef178c
in 2009, along with stephen friend, schadt founded
in 2009, along with stephen friend, schadt founded sage bionetworks, a nonprofit organization with the goal of encouraging collaboration between academic and commercial scientists in performing network-based studies of disease and making the data publicly available. when merck closed down the rosetta business unit, it ...
wikipedia
5f35fb5261765b8f68a12d9512750cfe5b00854c
demonstrating the ability to infer causal relationships among
demonstrating the ability to infer causal relationships among features in high dimensional data using dna variation information, schadt and his colleagues at merck began reconstructing predictive networks that were shown to be causally associated with disease, leading to the idea of targeting networks, not single genes...
wikipedia
1dba8815fc1e5cf64e61e732008e6e4ed3842640
in 1999, after becoming acquainted with stephen friend,
in 1999, after becoming acquainted with stephen friend, he was hired as chief scientist at rosetta inpharmatics, a startup biotech company focused on the generation and analysis of high-dimensional functional genomics data. merck acquired rosetta in 2001, which allowed schadt to combine large-scale molecular profiling ...
wikipedia
43aafd08b9a74b95b01370614a0c0c72047e4fc9
while completing his phd, schadt joined roche bioscience
while completing his phd, schadt joined roche bioscience in 1998 as a senior research scientist and began his work on dna microarrays, designing novel algorithms to process and interpret these data. he published some of the first independently developed algorithms to process gene chip data work that he later applied to...
wikipedia
2df9af347e4d864ac57fad8f7e1fc402a8e0c455
in 1983, schadt left high school early to
in 1983, schadt left high school early to enlist in the united states air force and joined a special operations/rescue unit. after sustaining a serious shoulder injury that required reconstructive surgery, schadt attended california polytechnic state university on a military scholarship to study computer science and ma...
wikipedia
c1af3b7570e166e2524a019fd0024002ec97d4bf
schadt's work combines supercomputing and advanced computational modeling
schadt's work combines supercomputing and advanced computational modeling with diverse biological data to understand the relationship between genes, gene products, other molecular features such as cells, organs, organisms, and communities and their impact on complex human traits such as disease. he is known for calling...
wikipedia
d2a6d47f13d1bc14695dc6e9b0032906bcee66c4
eric emil schadt (born january 31, 1965) is
eric emil schadt (born january 31, 1965) is an american mathematician and computational biologist. he is founder and former chief executive officer of sema4, a patient-centered health intelligence company, and dean for precision medicine and mount sinai professor in predictive health and computational biology at the ic...
wikipedia
a6bd5cc9377a9f23d6d8eacda3b4ff6f587545af
embelia schimperi is a shrub or small tree
embelia schimperi is a shrub or small tree that is capable of reaching 6 m (20 ft) in height with a red to brownish bark that is usually smooth. branches are lenticellate and the stems are smooth and free of hair. leaves are oblong to ovate in outline; leaflets can reach up to 12 cm (4.7 in) in length and 5 cm (2.0 in)...
wikipedia
31a9f277432af049aac9b623063721db5f6822c0
claire judith horwell is a professor of geohealth
claire judith horwell is a professor of geohealth in the department of earth sciences and institute of hazard, risk and resilience at durham university and the founding director of the international volcanic health hazard network (ivhhn). she studies the health hazards of natural and industrial mineral dusts and commun...
wikipedia
0e2fae05da657c8168ba0e6820c161ac639e6370
horwell has published more than 60 papers and
horwell has published more than 60 papers and several book chapters across disciplines including volcanology, petrology, behavioural science, social anthropology, toxicology, exposure science, public health and epidemiology, law and ethics. a full list of publications can be found at: https://www.durham.ac.uk/staff/cla...
wikipedia
da112b03eda1a73afae1392c99fb24fdafee483c
she created the health interventions in volcanic eruptions
she created the health interventions in volcanic eruptions (hive) consortium project (funded by elrha) to collect evidence on respiratory protection for communities. she investigated the effectiveness of facemasks distributed by agencies during volcanic eruptions, looking to identify whether or not they could adequatel...
wikipedia
59ee745f408c9c94146b1a27045a465980bfd235
she has worked with the pan american health
she has worked with the pan american health organization to introduce new epidemiological protocols for use in volcanic crises and has supported many governmental agencies and non-governmental organizations in indonesia, new zealand, singapore, japan, st vincent and mexico in preparing for, and responding to, community...
wikipedia
29f4ac803d85598a78c2c370f46c6115f5ce11f9
horwell studies the health hazards of mineral dusts,
horwell studies the health hazards of mineral dusts, and ways to support communities to protect themselves from inhaling particulate air pollution. she uses physicochemical analysis to establish whether or not, and how, mineral particles are harmful, as well as toxicological assessments to determine the respiratory haz...
wikipedia
8d30ea0f9616285d291fed93dcb4a8ac65435a01
horwell has served as an advisor to the
horwell has served as an advisor to the world health organization, uk cabinet office and public health england. she was appointed to the government of the united kingdom scientific advisory group for emergencies for volcanic eruptions in 2015. she was president (and, formerly, president-elect) and founding leader of th...
wikipedia
51362f98478d73d21281472fb34f550dfab82ac2
in 2003, horwell founded the international volcanic health
in 2003, horwell founded the international volcanic health hazard network through a leverhulme trust network grant. ivhhn provides information on the health hazards and impacts of volcanic emissions to the general public and civil protection agencies, and helps governments prepare for the health response to volcanic er...
wikipedia
5a43c547f7958d9532c29546c2f896482dd95b17
horwell became interested in volcanoes as a child
horwell became interested in volcanoes as a child when she visited mount batur in bali at the age of seven. her undergraduate degree was in environmental science at the university of east anglia, uk, where she studied environmental, earth and public health sciences. she moved to victoria university of wellington for he...
wikipedia
31a9f277432af049aac9b623063721db5f6822c0
claire judith horwell is a professor of geohealth
claire judith horwell is a professor of geohealth in the department of earth sciences and institute of hazard, risk and resilience at durham university and the founding director of the international volcanic health hazard network (ivhhn). she studies the health hazards of natural and industrial mineral dusts and commun...
wikipedia
977cea89bca0c73777633193f010128442ad3809
electronic system level (esl) design and verification is
electronic system level (esl) design and verification is an electronic design methodology, focused on higher abstraction level concerns. the term electronic system level or esl design was first defined by gartner dataquest, an eda-industry-analysis firm, on february 1, 2001. it is defined in esl design and verification...
wikipedia
e61834c44e872eb254b90f1b74169230d7624679
in esl design and verification, verification testing is
in esl design and verification, verification testing is used to prove the integrity of the design of the system or device. numerous verification techniques may be applied; these test methods are usually modified or customized to better accommodate the system or device under test. common esl verification methods include...
wikipedia
5fa82b3aed12b2aa1bf3bf6d7cfd85dd24454e61
other tools support import and export or intercommunication
other tools support import and export or intercommunication with components modelled at other levels of abstraction. for instance, an rtl component be converted into a systemc model using vtoc or verilator. and high level synthesis can be used to convert c models of a component into an rtl implementation.
wikipedia
ce458ccf4d3c46824e73cb89b0b59a5f1d462872
there are various types of eda tool used
there are various types of eda tool used for esl design. the key component is the virtual platform which is essentially a simulator. the virtual platform most commonly supports transaction-level modeling (tlm), where operations of one component on another are modelled with a simple method call between the objects model...
wikipedia
6176f22d3189b35ca76c57162ad3f5d59b7f46b5
esl is an established approach at many of
esl is an established approach at many of the world’s leading system-on-a-chip (soc) design companies, and is being used increasingly in system design. from its genesis as an algorithm modeling methodology with 'no links to implementation', esl is evolving into a set of complementary methodologies that enable embedded ...
wikipedia
391435da30cca50ba2da809d988b18c3cb3db0cd
the basic premise is to model the behavior
the basic premise is to model the behavior of the entire system using a low-level language such as c, c++, or using graphical "model-based" design tools. newer languages are emerging that enable the creation of a model at a higher level of abstraction including general purpose system design languages like sysml as well...
wikipedia
cfb79b32139ff70a108424bcc763a039e9f4f365
electronic system level (esl) design and verification is
electronic system level (esl) design and verification is an electronic design methodology, focused on higher abstraction level concerns. the term electronic system level or esl design was first defined by gartner dataquest, an eda-industry-analysis firm, on february 1, 2001. it is defined in esl design and verification...
wikipedia
c492ff817763b3cd3bb7d8a674ea5bf6ee263b4d
in mathematics, a commutative ring is a ring
in mathematics, a commutative ring is a ring in which the multiplication operation is commutative. the study of commutative rings is called commutative algebra. complementarily, noncommutative algebra is the study of ring properties that are not specific to commutative rings. this distinction results from the high numb...
wikipedia
138806d864b3592cbcf1f629e30a5490b3cc6cf9
a simplicial commutative ring is a simplicial object
a simplicial commutative ring is a simplicial object in the category of commutative rings. they are building blocks for (connective) derived algebraic geometry. a closely related but more general notion is that of e -ring.
wikipedia
5cc6265c10df3b929ea775c81a139837a4bf4f44
r is called a commutative differential graded algebra
r is called a commutative differential graded algebra (cdga). an example is the complex of differential forms on a manifold, with the multiplication given by the exterior product, is a cdga. the cohomology of a cdga is a graded-commutative ring, sometimes referred to as the cohomology ring. a broad range examples of gr...
wikipedia
5ade6be7fde471e18a21deaa2ab30fc26e03eaf1
by wedderburn's theorem, every finite division ring is
by wedderburn's theorem, every finite division ring is commutative, and therefore a finite field. another condition ensuring commutativity of a ring, due to jacobson, is the following: for every element r of r there exists an integer n > 1 such that r = r. if, r = r for every r, the ring is called boolean ring. more ge...
wikipedia
911fc78bb4235d0b4477eeb22682c701d079a949
is only right exact. if it is exact,
is only right exact. if it is exact, m is called flat. if r is local, any finitely presented flat module is free of finite rank, thus projective. despite being defined in terms of homological algebra, flatness has profound geometric implications. for example, if an r -algebra s is flat, the dimensions of the fibers
wikipedia
4f2f92773b6d9e8864b123657987e6e51e4c3124
vanishes for all large enough n. moreover, the
vanishes for all large enough n. moreover, the dimensions of these ext-groups, known as betti numbers, grow polynomially in n if and only if r is a local complete intersection ring. a key argument in such considerations is the koszul complex, which provides an explicit free resolution of the residue field k of a local ...
wikipedia
d8d75bc24039022e1cfd4a9ed45c4f905221647d
the latter functor is exact if m is
the latter functor is exact if m is projective, but not otherwise: for a surjective map e → f of r -modules, a map m → f need not extend to a map m → e. the higher ext functors measure the non-exactness of the hom-functor. the importance of this standard construction in homological algebra stems can be seen from the fa...
wikipedia
42ee2de911aede2116f376e120797fd2e9c21e8c
projective modules can be defined to be the
projective modules can be defined to be the direct summands of free modules. if r is local, any finitely generated projective module is actually free, which gives content to an analogy between projective modules and vector bundles. the quillen–suslin theorem asserts that any finitely generated projective module over k ...
wikipedia
8e27b6fd922c5ac53406922dbe109249f01215c2
if i is an ideal in a commutative
if i is an ideal in a commutative ring r, the powers of i form topological neighborhoods of 0 which allow r to be viewed as a topological ring. this topology is called the i -adic topology. r can then be completed with respect to this topology. formally, the i -adic completion is the inverse limit of the rings r / i. f...
wikipedia
81d8c2ad9d1b4a5563ab00df13707155b555904a
there are several ways to construct new rings
there are several ways to construct new rings out of given ones. the aim of such constructions is often to improve certain properties of the ring so as to make it more readily understandable. for example, an integral domain that is integrally closed in its field of fractions is called normal. this is a desirable proper...
wikipedia
900f5b7145b8dcf2a54db894bae28e1a2e0d7682
holds. a local ring in which equality takes
holds. a local ring in which equality takes place is called a cohen–macaulay ring. local complete intersection rings, and a fortiori, regular local rings are cohen–macaulay, but not conversely. cohen–macaulay combine desirable properties of regular rings (such as the property of being universally catenary rings, which ...
wikipedia
a9407cc91058eee9020f0620107b093e9c7901a0
a ring r is a set-theoretic complete intersection
a ring r is a set-theoretic complete intersection if the reduced ring associated to r, i.e., the one obtained by dividing out all nilpotent elements, is a complete intersection. as of 2017, it is in general unknown, whether curves in three-dimensional space are set-theoretic complete intersections.
wikipedia
2b0b426bb76ba9d54711cdd6453c2bd4e6169e53
is at least r − n. a ring
is at least r − n. a ring r is called a complete intersection ring if it can be presented in a way that attains this minimal bound. this notion is also mostly studied for local rings. any regular local ring is a complete intersection ring, but not conversely.
wikipedia
bbdeb696131f6b9f8ac8b94acb5308b68229ee7e
discrete valuation rings are equipped with a function
discrete valuation rings are equipped with a function which assign an integer to any element r. this number, called the valuation of r can be informally thought of as a zero or pole order of r. discrete valuation rings are precisely the one-dimensional regular local rings. for example, the ring of germs of holomorphic ...
wikipedia
89251c851fa535f11d97b56d15346f19cb35ab45
holds true, reflecting the idea that the cotangent
holds true, reflecting the idea that the cotangent (or equivalently the tangent) space has at least the dimension of the space spec r. if equality holds true in this estimate, r is called a regular local ring. a noetherian local ring is regular if and only if the ring (which is the ring of functions on the tangent cone...
wikipedia
a3a8fad4d74d582d66f3163dc25460eacdad33e7
the k -vector space m / m is
the k -vector space m / m is an algebraic incarnation of the cotangent space. informally, the elements of m can be thought of as functions which vanish at the point p, whereas m contains the ones which vanish with order at least 2. for any noetherian local ring r, the inequality
wikipedia
9e0f8dbb294ce0137ae4f6065d905c4719786161
at a prime ideal p is local. this
at a prime ideal p is local. this localization reflects the geometric properties of spec r "around p ". several notions and problems in commutative algebra can be reduced to the case when r is local, making local rings a particularly deeply studied class of rings. the residue field of r is defined as
wikipedia
57c2cda5f76200672793200adb2bff84f96fdae8
an r -algebra s is called finitely generated
an r -algebra s is called finitely generated (as an algebra) if there are finitely many elements s,..., s such that any element of s is expressible as a polynomial in the s. equivalently, s is isomorphic to
wikipedia
bf19bcc17f3fe9ecb62ee7eeaef020ed2afeec1f
commutative rings, together with ring homomorphisms, form a
commutative rings, together with ring homomorphisms, form a category. the ring z is the initial object in this category, which means that for any commutative ring r, there is a unique ring homomorphism z → r. by means of this map, an integer n can be regarded as an element of r. for example, the binomial formula
wikipedia
2f44020690cf29d132537ea098fba51de7c52e09
the kernel and image of f are defined
the kernel and image of f are defined by ker(f) = { r ∈ r, f (r) = 0} and im(f) = f (r) = { f (r), r ∈ r }. the kernel is an ideal of r, and the image is a subring of s.
wikipedia
57e7e1223bf63f38f8f7249f4d81c67f32225f4c
these conditions ensure f (0) = 0. similarly
these conditions ensure f (0) = 0. similarly as for other algebraic structures, a ring homomorphism is thus a map that is compatible with the structure of the algebraic objects in question. in such a situation s is also called an r -algebra, by understanding that s in s may be multiplied by some r of r, by setting
wikipedia
e14a67b9966ae49c1a975bdb0977b3ff80d1d016
for example, a field is zero-dimensional, since the
for example, a field is zero-dimensional, since the only prime ideal is the zero ideal. the integers are one-dimensional, since chains are of the form (0) ⊊ (p), where p is a prime number. for non-noetherian rings, and also non-local rings, the dimension may be infinite, but noetherian local rings have finite dimension...
wikipedia
74926209d0b35c7b8f735fac65efcb6636a9c5fa
the krull dimension (or dimension) dim r of
the krull dimension (or dimension) dim r of a ring r measures the "size" of a ring by, roughly speaking, counting independent elements in r. the dimension of algebras over a field k can be axiomatized by four properties:
wikipedia
b9d30b1418c0c6c6fb55fd454a70bda5c136fb86
similar to the fact that manifolds are locally
similar to the fact that manifolds are locally given by open subsets of r, affine schemes are local models for schemes, which are the object of study in algebraic geometry. therefore, several notions concerning commutative rings stem from geometric intuition.
wikipedia
c4bd43ac21bfb0fdfc47706ab09a9ef6e6c8f82b
the notion of a spectrum is the common
the notion of a spectrum is the common basis of commutative algebra and algebraic geometry. algebraic geometry proceeds by endowing spec r with a sheaf o {\displaystyle {\mathcal {o}}} (an entity that collects functions defined locally, i.e. on varying open subsets). the datum of the space and the sheaf is called an af...
wikipedia
c6d88dd3700488c287d91d5862e98a243f6d45a5
thus, maximal ideals reflect the geometric properties of
thus, maximal ideals reflect the geometric properties of solution sets of polynomials, which is an initial motivation for the study of commutative rings. however, the consideration of non-maximal ideals as part of the geometric properties of a ring is useful for several reasons. for example, the minimal prime ideals (i...
wikipedia
fe8f4fb76de48de19c43e792b2ef2050c494ab4a
interpreting f {\displaystyle f} as a function that
interpreting f {\displaystyle f} as a function that takes the value f mod p (i.e., the image of f in the residue field r / p), this subset is the locus where f is non-zero. the spectrum also makes precise the intuition that localisation and factor rings are complementary: the natural maps r → r and r → r / fr correspon...
wikipedia
239317393a17c36dff043872e555b230ecd6a341
the spectrum of a ring r {\displaystyle r},
the spectrum of a ring r {\displaystyle r}, denoted by spec r {\displaystyle {\text{spec}}\ r}, is the set of all prime ideals of r {\displaystyle r}. it is equipped with a topology, the zariski topology, which reflects the algebraic properties of r {\displaystyle r}: a basis of open subsets is given by
wikipedia
2b28675f147d041fa2870aa916ecdccfe6b9f57d
any maximal ideal is a prime ideal or,
any maximal ideal is a prime ideal or, more briefly, is prime. moreover, an ideal i {\displaystyle i} is prime if and only if the factor ring r / i {\displaystyle r/i} is an integral domain. proving that an ideal is prime, or equivalently that a ring has no zero-divisors can be very difficult. yet another way of expres...
wikipedia
0076615470e8dface4fae8bac37d3088f10a49bb
prime ideals, as opposed to prime elements, provide
prime ideals, as opposed to prime elements, provide a way to circumvent this problem. a prime ideal is a proper (i.e., strictly contained in r {\displaystyle r}) ideal p {\displaystyle p} such that, whenever the product a b {\displaystyle ab} of any two ring elements a {\displaystyle a} and b {\displaystyle b} is in p,...
wikipedia
771d11b9184129acce09f26c291980c6b3f65d82
becomes stationary eventually. despite the two conditions appearing
becomes stationary eventually. despite the two conditions appearing symmetric, noetherian rings are much more general than artinian rings. for example, z {\displaystyle \mathbb {z} } is noetherian, since every ideal can be generated by one element, but is not artinian, as the chain
wikipedia
9bf4588cee7260809572ee780e4067c54c4cc1ec
being noetherian is a highly important finiteness condition,
being noetherian is a highly important finiteness condition, and the condition is preserved under many operations that occur frequently in geometry. for example, if r {\displaystyle r} is noetherian, then so is the polynomial ring r {\displaystyle r\left} (by hilbert's basis theorem), any localization s − 1 r {\display...
wikipedia
22f351c0ae0731cf60f6174a5ca114fdbf0d9c07
becomes stationary, i.e. becomes constant beyond some index
becomes stationary, i.e. becomes constant beyond some index n {\displaystyle n}. equivalently, any ideal is generated by finitely many elements, or, yet equivalent, submodules of finitely generated modules are finitely generated.
wikipedia
a9d02846808d6cce914ae20153ab354582946ad7
an ideal is proper if it is strictly
an ideal is proper if it is strictly smaller than the whole ring. an ideal that is not strictly contained in any proper ideal is called maximal. an ideal m {\displaystyle m} is maximal if and only if r / m {\displaystyle r/m} is a field. except for the zero ring, any ring (with identity) possesses at least one maximal ...
wikipedia
ef6f1d167db86d4443d67300d0af48621c2b1899
for example, the ring z / n z
for example, the ring z / n z {\displaystyle \mathbb {z} /n\mathbb {z} } (also denoted z n {\displaystyle \mathbb {z} _{n}}), where n {\displaystyle n} is an integer, is the ring of integers modulo n {\displaystyle n}. it is the basis of modular arithmetic.
wikipedia
f63469fb52d62b563d3ce3c9b703a153d7423d22
the definition of ideals is such that "dividing"
the definition of ideals is such that "dividing" i {\displaystyle i} "out" gives another ring, the factor ring r / i {\displaystyle r/i}: it is the set of cosets of i {\displaystyle i} together with the operations
wikipedia
c3849077e6bf60c064decee6765642fb352492e7
an element a {\displaystyle a} is a prime
an element a {\displaystyle a} is a prime element if whenever a {\displaystyle a} divides a product b c {\displaystyle bc}, a {\displaystyle a} divides b {\displaystyle b} or c {\displaystyle c}. in a domain, being prime implies being irreducible. the converse is true in a unique factorization domain, but false in gene...
wikipedia
41bd5d6f168f8ca0dbd52a2d743b2889b9696dd5
is by either b {\displaystyle b} or c
is by either b {\displaystyle b} or c {\displaystyle c} being a unit. an example, important in field theory, are irreducible polynomials, i.e., irreducible elements in k {\displaystyle k\left}, for a field k {\displaystyle k}. the fact that z {\displaystyle \mathbb {z} } is a ufd can be stated more elementarily by sayi...
wikipedia
b22ddabc5c9e2ab4d1c7d5ea679601f0bb2cec39
unlike for general rings, for a principal ideal
unlike for general rings, for a principal ideal domain, the properties of individual elements are strongly tied to the properties of the ring as a whole. for example, any principal ideal domain r {\displaystyle r} is a unique factorization domain (ufd) which means that any element is a product of irreducible elements, ...
wikipedia
5a72bbbc0ed6297fa5478db6d2e29ee70ac6805f
if f {\displaystyle f} consists of a single
if f {\displaystyle f} consists of a single element r {\displaystyle r}, the ideal generated by f {\displaystyle f} consists of the multiples of r {\displaystyle r}, i.e., the elements of the form r s {\displaystyle rs} for arbitrary elements s {\displaystyle s}. such an ideal is called a principal ideal. if every idea...
wikipedia
380f616512f1b0efed8daf6922bfdce7e6ca34ff
any ring has two ideals, namely the zero
any ring has two ideals, namely the zero ideal { 0 } {\displaystyle \left\{0\right\}} and r {\displaystyle r}, the whole ring. these two ideals are the only ones precisely if r {\displaystyle r} is a field. given any subset f = { f j } j ∈ j {\displaystyle f=\left\{f_{j}\right\}_{j\in j}} of r {\displaystyle r} (where ...
wikipedia
e1fca75eac6a2c853649e9f38761f15db4bb35a6
ideals of a ring r {\displaystyle r} are
ideals of a ring r {\displaystyle r} are the submodules of r {\displaystyle r}, i.e., the modules contained in r {\displaystyle r}. in more detail, an ideal i {\displaystyle i} is a non-empty subset of r {\displaystyle r} such that for all r {\displaystyle r} in r {\displaystyle r}, i {\displaystyle i} and j {\displays...
wikipedia
887cd11883c97a893bbd1fb8d47c8b8c8e8e225a
a module of finite type is a module
a module of finite type is a module that has a finite spanning set. modules of finite type play a fundamental role in the theory of commutative rings, similar to the role of the finite-dimensional vector spaces in linear algebra. in particular, noetherian rings (see also § noetherian rings, below) can be defined as the...
wikipedia
7b22ef1baaa23e605b1aabe181e7f191245265e2
the study of modules is significantly more involved
the study of modules is significantly more involved than the one of vector spaces, since there are modules that do not have any basis, that is, do not contain a spanning set whose elements are linearly independents. a module that has a basis is called a free module, and a submodule of a free module needs not to be free...
wikipedia
5b88a6b6b17804e108fac7b3a54cb50cc59d3c27
for a ring r {\displaystyle r}, an r
for a ring r {\displaystyle r}, an r {\displaystyle r} - module m {\displaystyle m} is like what a vector space is to a field. that is, elements in a module can be added; they can be multiplied by elements of r {\displaystyle r} subject to the same axioms as for a vector space.
wikipedia
d0ac6055b727aabcaf4384ff0102f3d391484631
subject to certain rules that mimic the cancellation
subject to certain rules that mimic the cancellation familiar from rational numbers. indeed, in this language q {\displaystyle \mathbb {q} } is the localization of z {\displaystyle \mathbb {z} } at all nonzero integers. this construction works for any integral domain r {\displaystyle r} instead of z {\displaystyle \mat...
wikipedia
9a64cb46ac3692186c79681ad88aa42fa727c705
the localization of a ring is a process
the localization of a ring is a process in which some elements are rendered invertible, i.e. multiplicative inverses are added to the ring. concretely, if s {\displaystyle s} is a multiplicatively closed subset of r {\displaystyle r} (i.e. whenever s, t ∈ s {\displaystyle s,t\in s} then so is s t {\displaystyle st}) th...
wikipedia
1620a0ecb97fe30de678eeba1d68c1225d70e2f5
in contrast to fields, where every nonzero element
in contrast to fields, where every nonzero element is multiplicatively invertible, the concept of divisibility for rings is richer. an element a {\displaystyle a} of ring r {\displaystyle r} is called a unit if it possesses a multiplicative inverse. another particular type of element is the zero divisors, i.e. an eleme...
wikipedia
dd3fd837738ca840783578270064154ef5d48b24
if v {\displaystyle v} is some topological space,
if v {\displaystyle v} is some topological space, for example a subset of some r n {\displaystyle \mathbb {r} ^{n}}, real- or complex-valued continuous functions on v {\displaystyle v} form a commutative ring. the same is true for differentiable or holomorphic functions, when the two concepts are defined, such as for v...
wikipedia
0ab6b8f131011b7d5ef61fb058955debe9c31d9d
if r {\displaystyle r} is a given commutative
if r {\displaystyle r} is a given commutative ring, then the set of all polynomials in the variable x {\displaystyle x} whose coefficients are in r {\displaystyle r} forms the polynomial ring, denoted r {\displaystyle r\left}. the same holds true for several variables.
wikipedia
c9edd0f488499286cf3ae4f13bc2f5e51e8b5527
a field is a commutative ring where 0
a field is a commutative ring where 0 ≠ 1 {\displaystyle 0\not =1} and every non-zero element a {\displaystyle a} is invertible; i.e., has a multiplicative inverse b {\displaystyle b} such that a ⋅ b = 1 {\displaystyle a\cdot b=1}. therefore, by definition, any field is a commutative ring. the rational, real and comple...
wikipedia
b141103b1e6b67af912cb2f9b1c8981b8bc89409
an important example, and in some sense crucial,
an important example, and in some sense crucial, is the ring of integers z {\displaystyle \mathbb {z} } with the two operations of addition and multiplication. as the multiplication of integers is a commutative operation, this is a commutative ring. it is usually denoted z {\displaystyle \mathbb {z} } as an abbreviatio...
wikipedia
8faf7eeb3eba9a25b1bf452785f0da9f198244ee
a ring is a set r {\displaystyle r}
a ring is a set r {\displaystyle r} equipped with two binary operations, i.e. operations combining any two elements of the ring to a third. they are called addition and multiplication and commonly denoted by " + {\displaystyle +} " and " ⋅ {\displaystyle \cdot } "; e.g. a + b {\displaystyle a+b} and a ⋅ b {\displaystyl...
wikipedia
c492ff817763b3cd3bb7d8a674ea5bf6ee263b4d
in mathematics, a commutative ring is a ring
in mathematics, a commutative ring is a ring in which the multiplication operation is commutative. the study of commutative rings is called commutative algebra. complementarily, noncommutative algebra is the study of ring properties that are not specific to commutative rings. this distinction results from the high numb...
wikipedia
703f453119a0a5569d44f262410d8e6c27bf0d7e
david k. littman is an american former ice
david k. littman is an american former ice hockey goaltender. he played three games in the national hockey league: two with the buffalo sabres and one with the tampa bay lightning between 1991 and 1993. the rest of his career, which lasted from 1989 to 2000, was mainly spent in the minor international hockey league. he...
wikipedia
c1f536ac5dd42a2a6704f3aee45d6705ca9aa7f0
as a result of his successful stints with
as a result of his successful stints with the atlanta knights, littman was selected to compete with team usa at the 1994 iihf world championship, where they finished fourth in the tournament. before his retirement, littman played with the ihl's orlando solar bears, recording 53 wins over two years before a career-endin...
wikipedia
38ab3198d6d2af5920acf653d3eb425da599d2a5
on august 28, 1992, littman signed with the
on august 28, 1992, littman signed with the new nhl expansion team, the tampa bay lightning. although he began the season in the minor leagues with the atlanta knights, littman was recalled to the nhl in november 1992. his stay in the national hockey league was short-lived and he was reassigned to the ihl. he became a ...
wikipedia
809dbdc49cdfb410404c4749da5eca3034dcb750
littman attended the sabres training camp but was
littman attended the sabres training camp but was reassigned to their international hockey league (ihl) affiliate, the rochester americans, to begin the 1989–90 season. however, the 1990–91 would prove to be a breakout season for him. on january 29, 1991, littman made his nhl debut by replacing darcy wakaluk in the sec...
wikipedia
6c500477ca4ed9c1f10f28b0426b7e9e027161da
littman spent four years at boston college studying
littman spent four years at boston college studying communications. in his senior year, littman served as one of three captains on the team as the eagles qualified for the ncaa final eight. he ended his season with.912 saves and a.895 percentage. in 2000, his bc record of 2,548 career saves was broken by scott clemmens...
wikipedia
cb686f65e0c3bc38a8a43f9f2507863ee03330c0
david k. littman (born june 13, 1967) is
david k. littman (born june 13, 1967) is an american former ice hockey goaltender. he played three games in the national hockey league: two with the buffalo sabres and one with the tampa bay lightning between 1991 and 1993. the rest of his career, which lasted from 1989 to 2000, was mainly spent in the minor internatio...
wikipedia
145b0fd3915ba07382ce2106908d9848ad1b2ef4
epimedium, also known as barrenwort, bishop's hat, fairy
epimedium, also known as barrenwort, bishop's hat, fairy wings, horny goat weed, or yin yang huo, is a genus of flowering plants in the family berberidaceae. the majority of the species are endemic to china, with smaller numbers elsewhere in asia, and a few in the mediterranean region. epimedium species are deciduous o...
wikipedia
c06cf3fea4d6bff3a8d1d42ccb829fd2184b8761
epimedium wushanense contains a number of flavonoids. 37
epimedium wushanense contains a number of flavonoids. 37 compounds were characterized from the underground and aerial parts of the plant. among them, 28 compounds were prenylflavonoids. the predominant flavonoid, epimedin c, ranged from 1.4 to 5.1% in aerial parts and 1.0 to 2.8% in underground parts.
wikipedia
387cc7478b2f0485a658fb159f883a9af8522f63
while they can be successfully propagated in early
while they can be successfully propagated in early spring, epimediums are best divided in late summer, with the aim of promoting rapid re-growth of roots and shoots before the onset of winter. several breeders (in particular darrell diano probst, tim branney & robin white) have also undertaken their own hybridization p...
wikipedia
7e288c4cae86f3163b8d6f248ba76dc061b26883
some varieties and hybrids have been in western
some varieties and hybrids have been in western cultivation for the last 100 to 150 years. there is now a wide array of new chinese species being cultivated in the west, many of which have only recently been discovered, and some of which have yet to be named. there are also many older japanese hybrids and forms, extend...
wikipedia
c12785472df00854a73f6a72c36e64df5274d316
the genus was given its name by carl
the genus was given its name by carl linnaeus in 1753, in describing the european species e. alpinum. the name is a latinized version of a greek name for an unidentifiable plant, epimedion, that is mentioned in pliny's natural history (xxvii.57). the meaning of the original name is unclear.
wikipedia
af1b032d0119342c90c67c98c3b9bfcf5bb649e2
individual flowers have parts in fours. there are
individual flowers have parts in fours. there are four smaller outer sepals, usually greenish and shed when the flower opens. moving inwards, these are followed by four larger petal-like inner sepals, often brightly coloured. inside the sepals are four true petals. these may be small and flat, but often have a complex ...
wikipedia
25b218b75e0facb882ef35d562eaca405041f2f3
species of epimedium are herbaceous perennials, growing from
species of epimedium are herbaceous perennials, growing from an underground rhizome. their growth habits are somewhat variable. some have solitary stems, others have a "tufted" habit, with multiple stems growing close together. there may be several leaves to a stem or the leaves may be solitary, produced from the base ...
wikipedia
90bcb3134ff6c19cb4276fb60a7dacdfaba8a905
the species used as a dietary supplement is
the species used as a dietary supplement is epimedium grandiflorum. it contains icariin, which is a weak pde5 inhibitor, in vitro. its clinical effects are unknown. while there is little clinical evidence to date, as sildenafil, vardenafil, and tadalafil – sold under the brand names viagra, levitra and cialis – are all...
wikipedia
e78501d6d90b2d77179d0945cdf8884c60095171
epimedium, also known as barrenwort, bishop's hat, fairy
epimedium, also known as barrenwort, bishop's hat, fairy wings, horny goat weed, or yin yang huo (chinese: 淫羊藿; pinyin: yínyánghùo; wade–giles: yin²-yang²-huo⁴), is a genus of flowering plants in the family berberidaceae. the majority of the species are endemic to china, with smaller numbers elsewhere in asia, and a fe...
wikipedia