Search results for "CoDi"

showing 10 items of 1391 documents

Anomalies on codimension growth of algebras

2015

Abstract This paper deals with the asymptotic behavior of the sequence of codimensions c n ⁢ ( A ) ${c_{n}(A)}$ , n = 1 , 2 , … , ${n=1,2,\ldots,}$ of an algebra A over a field of characteristic zero. It is shown that when such sequence is polynomially bounded, then lim sup n → ∞ ⁡ log n ⁡ c n ⁢ ( A ) ${\limsup_{n\to\infty}\log_{n}c_{n}(A)}$ and lim inf n → ∞ ⁡ log n ⁡ c n ⁢ ( A ) ${\liminf_{n\to\infty}\log_{n}c_{n}(A)}$ can be arbitrarily distant. Also, in case the codimensions are exponentially bounded, we can construct an algebra A such that exp ⁡ ( A ) = 2 ${\exp(A)=2}$ and, for any q ≥ 1 ${q\geq 1}$ , there are infinitely many integers n such that c n ⁢ ( A ) > n q ⁢ 2 n ${c_{n}(A)&…

General MathematicsApplied Mathematics010102 general mathematicsCodimensionPolynomial identity01 natural sciencesExponential growth010101 applied mathematicsAlgebraExponential growthCodimensionMathematics (all)0101 mathematicsMathematics
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Mappings of finite distortion: Sharp Orlicz-conditions

2003

We establish continuity, openness and discreteness, and the condition $(N)$ for mappings of finite distortion under minimal integrability assumptions on the distortion.

General MathematicsDistortionMathematical analysisData_MISCELLANEOUSComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONData_CODINGANDINFORMATIONTHEORYfinite distortionTopologycontinuityopenness and discretenessMathematicsOrlicz conditions30C65
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Tailoring a pair of pants

2021

Abstract We show how to deform the map Log : ( C ⁎ ) n → R n such that the image of the complex pair of pants P ∘ ⊂ ( C ⁎ ) n is the tropical hyperplane by showing an (ambient) isotopy between P ∘ ⊂ ( C ⁎ ) n and a natural polyhedral subcomplex of the product of the two skeleta S × Σ ⊂ A × C of the amoeba A and the coamoeba C of P ∘ . This lays the groundwork for having the discriminant to be of codimension 2 in topological Strominger-Yau-Zaslow torus fibrations.

General MathematicsImage (category theory)010102 general mathematicsTorusCodimensionMathematics::Geometric Topology01 natural sciencesCombinatoricsMathematics::Algebraic GeometryDiscriminantHyperplane0103 physical sciencesAmoeba (mathematics)Isotopy010307 mathematical physics0101 mathematicsMathematics::Symplectic GeometryPair of pantsMathematicsAdvances in Mathematics
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Differential Identities and Varieties of Almost Polynomial Growth

2022

Let V be an L-variety of associative L-algebras, i.e., algebras where a Lie algebra L acts on them by derivations, and let c(n)(L) (V), n >= 1, be its Lcodimension sequence. If V is generated by a finite-dimensional L-algebra, then such a sequence is polynomially bounded only if V does not contain UT2, the 2 x 2 upper triangular matrix algebra with trivial L-action, and UT2 epsilon where L acts on UT2 as the 1-dimensional Lie algebra spanned by the inner derivation epsilon induced by e11. In this paper we completely classify all the L-subvarieties of var(L)(UT2) and var(L)(UT2 epsilon) by giving a complete list of finite-dimensional L-algebras generating them.

General Mathematicspolynomial identity differential identity variety of algebras codimension growth
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Sequence and evolution of the gene for the monomeric globin I and its linkage to genes coding for dimeric globins in the insect Chironomus thummi.

1995

We isolated genomic clones containing sequences encoding globins I and IA from a Chironomus thummi thummi genomic library. Three clones contain globin IA (ctt-1A) genes, while one contains a globin I (ctt-1) gene. The coding regions of the four genes are identical except for the single base substitution accounting for the globin I/IA polymorphism. The noncoding DNA flanking the coding region is more than 98% similar, confirming a previous hypothesis that the globin ctt-1 and ctt-1A genes are alleles. Hemoglobins I and IA are monomeric in the insect hemolymph. Earlier in situ hybridization studies suggested that monomeric and dimeric globin genes are clustered at different chromosomal loci. …

Genetic LinkageMolecular Sequence DataGenes InsectBiologyChironomidaechemistry.chemical_compoundMolecular evolutionhemic and lymphatic diseasesGeneticsCoding regionAnimalsGenomic libraryGlobinAmino Acid SequenceMolecular BiologyGeneEcology Evolution Behavior and SystematicsIn Situ HybridizationGeneticsPolytene chromosomeBase SequenceSequence Homology Amino AcidChromosome MappingMolecular biologyNoncoding DNABiological EvolutionGlobinschemistrySequence AlignmentDNAJournal of molecular evolution
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Using DNA barcodes to detect non-indigenous species: the case of the Asian copepod Mesocyclops pehpeiensis Hu, 1943 (Cyclopidae) in two regions of th…

2015

To date, little attention has been paid to analyses of copepods as exotic species. The genusMesocyclops, a freshwater cyclopoid, has a worldwide distribution, but individual species within the genus have a quite restricted geographical range.Mesocyclops pehpeiensisHu, 1943 is a Central-East Asian species, rarely found outside of this area, and when it appears should be considered as non-native. Based on morphology and DNA barcode analyses, using the COI gene, we confirmed records ofM. pehpeiensisin two ponds in Mexico and in a rice paddy near Valencia, Spain. The morphology of this species, based on morphometric analyses, was found to be variable, but DNA barcoding confirmed the same identi…

Genetic divergenceMesocyclopsRange (biology)GenusEcologyAnimal Science and ZoologyIntroduced speciesAquatic ScienceDisjunctBiologybiology.organism_classificationDNA barcodingCyclopidaeCrustaceana
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DNA barcode reference library for Iberian butterflies enables a continental-scale preview of potential cryptic diversity

2015

How common are cryptic species - those overlooked because of their morphological similarity? Despite its wide-ranging implications for biology and conservation, the answer remains open to debate. Butterflies constitute the best-studied invertebrates, playing a similar role as birds do in providing models for vertebrate biology. An accurate assessment of cryptic diversity in this emblematic group requires meticulous case-by-case assessments, but a preview to highlight cases of particular interest will help to direct future studies. We present a survey of mitochondrial genetic diversity for the butterfly fauna of the Iberian Peninsula with unprecedented resolution (3502 DNA barcodes for all 2…

Genetic diversitySpecies complexMultidisciplinaryEcologyFaunaBiodiversityBiodiversityDNA15. Life on landBiologyBiología y Biomedicina / BiologíaVertebrate BiologyDNA barcodingArticleSpainButterflyAnimalsDNA Barcoding TaxonomicCryptic biodiversityIdentification (biology)14. Life underwaterButterfliesIberian PeninsulaScientific Reports
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Low frequency and rare coding variation contributes to multiple sclerosis risk

2018

AbstractMultiple sclerosis is a common, complex neurological disease, where almost 20% of risk heritability can be attributed to common genetic variants, including >230 identified by genome-wide association studies (Patsopoulos et al., 2017). Multiple strands of evidence suggest that the majority of the remaining heritability is also due to the additive effects of individual variants, rather than epistatic interactions between these variants, or mutations exclusive to individual families. Here, we show in 68,379 cases and controls that as much as 5% of this heritability is explained by low-frequency variation in gene coding sequence. We identify four novel genes driving MS risk independe…

Genetics0303 health sciencesLinkage disequilibriumMultiple sclerosisDiseaseBiologyHeritabilitymedicine.disease3. Good health03 medical and health sciences0302 clinical medicinemedicineEpistasisCoding regionGene030217 neurology & neurosurgery030304 developmental biologyGenetic association
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Are polymorphisms of the β3 -adrenoceptor gene associated with an altered bladder function?

2012

Aims As the presence of a Trp64Arg polymorphism of the gene encoding the β3-adrenoceptor (B3AR) has been linked to the presence of overactive bladder, we investigated whether additional polymorphisms are detectable in this gene and explore their relationships parameters related to lower urinary tract function. Methods The coding region and adjacent stretches of the B3AR gene was sequenced in 91 patients. In total, 1015 patients from a single academic hospital were genotyped for the presence of two single nucleotide polymorphisms. Symptom scores and parameters from pressure-flow studies were analyzed relative to genotype in the B3AR gene. Results No frequent novel polymorphisms were detected…

GeneticsAdrenergic receptorbusiness.industryUrology030232 urology & nephrologySingle-nucleotide polymorphismmedicine.disease03 medical and health sciences0302 clinical medicineOveractive bladder030220 oncology & carcinogenesisGenotypeMedicineCoding regionNeurology (clinical)Gene polymorphismAllelebusinessGeneNeurourology and Urodynamics
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Characterization of a Cu/Zn Superoxide dismutase-encoding gene region in Drosophila willistoni

1994

A Cu/Zn superoxide dismutase-encoding gene (Sod) from Drosophila willistoni was cloned and sequenced. The gene shows a typical structure for a fruit-fly Sod gene, with a coding region of 462 bp in two exons separated by a 417-bp intron. Comparison of the Sod sequences from D. willistoni and D. melanogaster suggests that these species are only remotely related. Downstream from the Sod gene, there is an ORF on the opposite strand that putatively encodes the last exon of an unidentified gene. The polyadenylation signals of the two genes are separated by only 61 bp in D. willistoni, conforming to the common picture of compact dipteran genomes.

GeneticsBase SequencebiologyPolyadenylationSuperoxide DismutaseMolecular Sequence DataIntronDNAGeneral Medicinebiology.organism_classificationMolecular biologyDrosophila virilisOpen Reading FramesExonGeneticsMelanogasterAnimalsCoding regionDrosophilaDrosophila willistoniAmino Acid SequenceGeneGene
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