Search results for "Gari"

showing 10 items of 716 documents

Expression of a plant serine O-acetyltransferase inSaccharomyces cerevisiae confers osmotic tolerance and creates an alternative pathway for cysteine…

2004

Screening of a sugar beet (Beta vulgaris cv. Dita) cDNA library for clones able to confer osmotic tolerance to the osmosensitive gpd1 mutant of Saccharomyces cerevisiae identified a novel serine O-acetyltransferase (BvSAT; EC 2.3.1.30). This enzyme is involved in cysteine biosynthesis in plants and bacteria, producing O-acetylserine, which is converted into cysteine in a reaction catalysed by O-acetylserine sulphydrylase (EC 4.2.99.8). This pathway is not conserved in yeast, where cysteine is synthesized in a four-step pathway starting with homoserine and having O-acetylhomoserine, homocysteine and cystathionine as intermediates. Expression of BvSAT in yeast takes advantage of the activity …

DNA ComplementaryOsmotic shockMolecular Sequence DataSaccharomyces cerevisiaeHomoserineBioengineeringSaccharomyces cerevisiaeBiologyApplied Microbiology and BiotechnologyBiochemistrySerinechemistry.chemical_compoundAcetyltransferasesGeneticsSerine O-acetyltransferaseCysteineSulfhydryl CompoundsAmino AcidsDNA PrimersBase SequenceGene Transfer Techniquesbiology.organism_classificationCystathionine beta synthaseYeastBiochemistrychemistrybiology.proteinBeta vulgarisSerine O-AcetyltransferaseBiotechnologyCysteineYeast
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Social transmission in the wild can reduce predation pressure on novel prey signals

2021

Funder: Suomen Kulttuurirahasto (Finnish Cultural Foundation); doi: https://doi.org/10.13039/501100003125

DYNAMICS0106 biological sciences0301 basic medicineINFORMATIONBehavioural ecologyAVOIDANCEGeneral Physics and AstronomyPREFERENCESALTERNATIVE PREYEvolutionary ecology01 natural sciencesConformityPredationlaw.inventionlaw/631/181/2481kulttuurievoluutioPasseriformesCOLORATIONcultural evolutionsinitiainenmedia_commoneducation.field_of_studyMultidisciplinarybiologyEcologyCyanistesQarticlebehavioural ecologyCONFORMITYtalitiainenBiological Evolutionsosiaalinen oppiminen/631/158/856evoluutioekologiaTransmission (mechanics)/631/158/8571181 Ecology evolutionary biologycoevolution/631/181/1403media_common.quotation_subjectSciencePopulationCultural evolutioneläinten käyttäytyminen010603 evolutionary biologyGeneral Biochemistry Genetics and Molecular Biology03 medical and health sciencesGREGARIOUSNESSAvoidance LearningJuvenileAnimalsSelection GeneticeducationEvolutionary dynamicsSocial BehaviorParusGeneral Chemistrybiology.organism_classificationBLACKBIRDSPrunus dulcisEVOLUTIONsaalistusUnited Kingdom030104 developmental biologyPredatory Behaviorevolutionary ecologyRemote Sensing TechnologyVocalization AnimalCoevolutionNature Communications
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Eliptisko līkņu kriptosistēmu pielietojumi

2016

IT nozares attīstība un daudzpusīgie interneta lietojumi prasa drošākus un efektīvākus datu aizsardzības risinājumus. Darbā aprakstīta personalizētas, publiskās atslēgas kriptogrāfiskas sistēmas izstrāde, kas balstīta uz Veierštrāsa eliptiskajām līknēm pār galīgu pirmskaitļu lauku. Šādu kriptogrāfisku sistēmu fundamentālā drošība saistās ar algoritmiski sarežģīto diskrētā logaritma problēmu eliptiskajām līknēm. Eliptisko līkņu bāzētas kriptogrāfiskas sistēmas, salīdzinājumā ar populāro RSA sistēmu, nodrošina augstāku drošības līmeni pie vienāda atslēgu garuma, tādējādi iespējami efektīvi datu aizsardzības risinājumi ar labāku veiktspēju. Darbā tiek skaidroti vispārīgi eliptisko līkņu kripto…

Datorzinātnediskrētā logaritma problēmaeliptisko līkņu kriptogrāfijaeliptiskās līkneskriptogrāfiskas sistēmas
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The importance of a highly active and DeltapH-regulated diatoxanthin epoxidase for the regulation of the PS II antenna function in diadinoxanthin cyc…

2005

The present study focuses on the regulation of diatoxanthin (Dtx) epoxidation in the diadinoxanthin (Ddx) cycle containing algae Phaeodactylum tricornutum, Thalassiosira pseudonana, Cyclotella meneghiniana and Prymnesium parvum and its significance for the control of the photosystem II (PS II) antenna function. Our data show that Dtx epoxidase can exhibit extremely high activities when algal cells are transferred from high light (HL) to low light (LL). Under HL conditions, Dtx epoxidation is strongly inhibited by the light-driven proton gradient. Uncoupling of the cells during HL illumination restores the high epoxidation rates observed during LL. In Ddx cycle containing algae, non-photoche…

DiatomsPhotosystem IIbiologyLightPhysiologyZeaxanthin epoxidaseAlgal ProteinsDiadinoxanthinDiatoxanthinEukaryotaPhotosystem II Protein ComplexPlant ScienceHydrogen-Ion ConcentrationXanthophyllsPhotochemistrychemistry.chemical_compoundchemistryPhotoprotectionbiology.proteinElectrochemical gradientChlorella vulgarisOxidoreductasesAgronomy and Crop ScienceChlorophyll fluorescenceViolaxanthinJournal of plant physiology
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Analytic Extension of Non Quasi - Analytic Whitney Jets of Beurling Type

1998

Let (Mr)r∈ℕ0 be a logarithmically convex sequence of positive numbers which verifies M0 = 1 as well as Mr ≥ 1 for every r ∈ ℕ and defines a non quasi - analytic class. Let moreover F be a closed proper subset of ℝn. Then for every function f on ℝn belonging to the non quasi - analytic (Mr)-class of Beurling type, there is an element g of the same class which is analytic on ℝ,nF and such that Dαf(x) = Dαg(x) for every α ∈ ℕn0 and x ∈ F.

Discrete mathematicsClass (set theory)Pure mathematicsSequenceLogarithmically convex functionGeneral MathematicsExtension (predicate logic)Function (mathematics)Element (category theory)Type (model theory)MathematicsMathematische Nachrichten
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Lower space bounds for randomized computation

1994

It is a fundamental problem in the randomized computation how to separate different randomized time or randomized space classes (c.f., e.g., [KV87, KV88]). We have separated randomized space classes below log n in [FK94]. Now we have succeeded to separate small randomized time classes for multi-tape 2-way Turing machines. Surprisingly, these “small” bounds are of type n+f(n) with f(n) not exceeding linear functions. This new approach to “sublinear” time complexity is a natural counterpart to sublinear space complexity. The latter was introduced by considering the input tape and the work tape as separate devices and distinguishing between the space used for processing information and the spa…

Discrete mathematicsCombinatoricsTuring machinesymbols.namesakeSublinear functionKolmogorov complexitysymbolsType (model theory)Binary logarithmSpace (mathematics)Time complexityWord (computer architecture)Mathematics
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First-order expressibility of languages with neutral letters or: The Crane Beach conjecture

2005

A language L over an alphabet A is said to have a neutral letter if there is a letter [email protected]?A such that inserting or deleting e's from any word in A^* does not change its membership or non-membership in L. The presence of a neutral letter affects the definability of a language in first-order logic. It was conjectured that it renders all numerical predicates apart from the order predicate useless, i.e., that if a language L with a neutral letter is not definable in first-order logic with linear order, then it is not definable in first-order logic with any set N of numerical predicates. Named after the location of its first, flawed, proof this conjecture is called the Crane Beach …

Discrete mathematicsConjectureComputer Networks and CommunicationsApplied MathematicsFirst orderNumerical predicatesPredicate (grammar)Theoretical Computer ScienceFirst-order logicIterated logarithmCombinatoricsComputational Theory and MathematicsRegular languageDatabase theoryCircuit complexityFirst-order logicCircuit uniformityMathematicsJournal of Computer and System Sciences
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Application of kolmogorov complexity to inductive inference with limited memory

1995

A b s t r a c t . We consider inductive inference with limited memory[l]. We show that there exists a set U of total recursive functions such that U can be learned with linear long-term memory (and no short-term memory); U can be learned with logarithmic long-term memory (and some amount of short-term memory); if U is learned with sublinear long-term memory, then the short-term memory exceeds arbitrary recursive function. Thus an open problem posed by Freivalds, Kinber and Smith[l] is solved. To prove our result, we use Kolmogorov complexity.

Discrete mathematicsHardware_MEMORYSTRUCTURESKolmogorov complexityLogarithmSublinear functionKolmogorov structure functionChain rule for Kolmogorov complexityOpen problemInductive probabilityInductive reasoningMathematics
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Law of the Iterated Logarithm

2020

For sums of independent random variables we already know two limit theorems: the law of large numbers and the central limit theorem. The law of large numbers describes for large \(n\in \mathbb{N}\) the typical behavior, or average value behavior, of sums of n random variables. On the other hand, the central limit theorem quantifies the typical fluctuations about this average value.

Discrete mathematicsIterated logarithmNatural logarithm of 2LogarithmLaw of large numbersLaw of the iterated logarithmLimit (mathematics)Random variableMathematicsCentral limit theorem
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Quasihyperbolic boundary conditions and Poincaré domains

2002

We prove that a domain in ${\Bbb R}^n$ whose quasihyperbolic metric satisfies a logarithmic growth condition with coefficient $\beta\le 1$ is a (q,p)-\Poincare domain for all p and q satisfying $p\in[1,\infty)\cap(n-n\beta,n)$ and $q\in[p,\beta p^*)$ , where $p^*=np/(n-p)$ denotes the Sobolev conjugate exponent. An elementary example shows that the given ranges for p and q are sharp. The proof makes use of estimates for a variational capacity. When p=2 we give an application to the solvability of the Neumann problem on domains with irregular boundaries. We also discuss the relationship between this growth condition on the quasihyperbolic metric and the s-John condition.

Discrete mathematicsPure mathematicsGeneral MathematicsLogarithmic growthA domainSobolev spacesymbols.namesakePoincaré conjectureExponentNeumann boundary conditionsymbolsBeta (velocity)Boundary value problemMathematicsMathematische Annalen
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