Search results for "complexity"

showing 10 items of 1094 documents

Real quadrics in C n , complex manifolds and convex polytopes

2006

In this paper, we investigate the topology of a class of non-Kähler compact complex manifolds generalizing that of Hopf and Calabi-Eckmann manifolds. These manifolds are diffeomorphic to special systems of real quadrics Cn which are invariant with respect to the natural action of the real torus (S1)n onto Cn. The quotient space is a simple convex polytope. The problem reduces thus to the study of the topology of certain real algebraic sets and can be handled using combinatorial results on convex polytopes. We prove that the homology groups of these compact complex manifolds can have arbitrary amount of torsion so that their topology is extremely rich. We also resolve an associated wall-cros…

General MathematicsHolomorphic functionSubspace arrangementsPolytope52C35Combinatorics52B05Ricci-flat manifoldTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYConvex polytopeComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATIONMathematics::Symplectic Geometry32Q55Mathematics32M17Equivariant surgeryTopology of non-Kähler compact complex manifoldsMathematics::Geometric TopologyManifoldAffine complex manifoldsMathematics::Differential GeometryDiffeomorphismComplex manifoldCombinatorics of convex polytopesSingular homologyReal quadrics
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Lack of linkage between gene(s) controlling the synthesis of the seventh component of complement and the HLA region on chromosome No. 6 in man.

1976

The family of an individual was studied who lacks the seventh component of complement in his serum (C7 homozygous deficiency). Both parents are C7 heterozygousdeficient. In this investigation, the following parameters were determined: complement components in functional and immunochemical tests; HLA-A,B antigens, HLA-D (MLC) determinants; the Bf system; glyoxalase I and B cell antigens. No evidence for linkage between the immunogenetic linkage group on chromosome 6 and gene(s) controlling the synthesis of the seventh component of complement was obtained. This is in accordance with the assumption that only genes controlling components of the initiating rather than the membrane attack unit of…

GeneticsChromosomes Human 6-12 and XMaleGenetic LinkageChromosomeHuman leukocyte antigenComplement System ProteinsBiologyComplement factor BHuman geneticsComplement C7Complement (complexity)medicine.anatomical_structureAntigenHLA AntigensHistocompatibility AntigensGeneticsmedicineHumansLymphocyte Culture Test MixedChildGeneGenetics (clinical)B cellHuman genetics
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Tracking evolutionary trends towards increasing complexity: a case study in Cyanobacteria

2020

AbstractProgressive evolution, the tendency towards increasing complexity, is a controversial issue in Biology, whose resolution requires a proper measurement of complexity. Genomes are the best entities to address this challenge, as they record the history and information gaining of organisms in their ongoing biotic and environmental interactions. Using six metrics of genome complexity, none of which is primarily associated to biological function, we measure genome complexity in 91 genomes from the phylum Cyanobacteria. Several phylogenetic analyses reveal the existence of progressive evolution towards higher genome complexity: 1) all the metrics detect strong phylogenetic signals; 2) ridg…

Genome evolutionNatural selectionPhylogenetic treeGenome complexityEvolutionary biologyBiologyGenomePhylum Cyanobacteria
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Strategic Management Simulations: the German Case

1995

This chapter initially considers the rationale and potential value of games and simulations for managerial and executive assessment. Several shortcomings of existing techniques are discussed. In contrast, characteristics of the Strategic Management Simulations (SMS) are described in terms of applicability, reliability, construct validity, predictive validity and other factors. This chapter provides validity information about a German version of the SMS system via a case analysis procedure with two German samples.

GermanPredictive validityComputer scienceManagement sciencelanguageContrast (statistics)Cognitive complexityConstruct validityStrategic managementlanguage.human_languageReliability (statistics)Case analysis
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Territories, observation and governance. Tools, methods and realities

2011

The thesis is presented in three parts which include the three key words of the title and put intoperspective the function of territorial observation, with an approach to complexity mostly empiricaland constantly referring to systemics.The first part focuses on the polysemic notion of territory. Modeling the process of territorializationallows us to bypass the semantic difficulty that arises from multiple uses of the term in the literatureand in interviews conducted with experts. The territory is then revealed in different forms ofcombinations of tangible and intangible dimensions, and individual or collective representations.The second part is based on concrete achievements of observatorie…

GovernanceObservatoireSystémique[SHS.GEO] Humanities and Social Sciences/GeographyObservationComplexity[SHS.GEO]Humanities and Social Sciences/Geography[ SHS.GEO ] Humanities and Social Sciences/GeographyToolsSystemicsTerritoireMethods and realitiesGouvernanceTerritoryTerritorialisation
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Parallel Algorithms for Listing Well-Formed Parentheses Strings

1998

We present two cost-optimal parallel algorithms generating the set of all well-formed parentheses strings of length 2n with constant delay for each generated string. In our first algorithm we generate in lexicographic order well-formed parentheses strings represented by bitstrings, and in the second one we use the representation by weight sequences. In both cases the computational model is based on an architecture CREW PRAM, where each processor performs the same algorithm simultaneously on a different set of data. Different processors can access the shared memory at the same time to read different data in the same or different memory locations, but no two processors are allowed to write i…

Gray codeSet (abstract data type)Shared memoryHardware and ArchitectureComputer scienceString (computer science)Parallel algorithmParallel random-access machineLexicographical orderTime complexityAlgorithmSoftwareTheoretical Computer ScienceParallel Processing Letters
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Influence of Macrophage Activation on the Synthesis of Complement Components C2, C3, C4

1982

Macrophages are a major site of complement synthesis. In the guinea pig production of complement components C1, C2, C4, C3, D, B, and P by peritoneal macrophages has been demonstrated (reviewed in Ref. 1). Whereas marked differences exist in biological activity between resident, elicited and activated macrophages (2), we investigated whether this holds true for the synthesis and secretion of complement components C2, C3, and C4.

Guinea pigChemistryMacrophageBiological activitySecretionComplement (complexity)Cell biologyComplement components
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Facilitating Access to Health Web Pages with Different Language Complexity Levels

2019

The number of people looking for health information on the Internet is constantly growing. When searching for health information, different types of users, such as patients, clinicians or medical researchers, have different needs and should easily find the information they are looking for based on their specific requirements. However, generic search engines do not make any distinction among the users and, often, overload them with the provided amount of information. On the other hand, specific search engines mostly work on medical literature and specialized web sites are often not free and contain focused information built by hand. This paper presents a method to facilitate the search of he…

Health Information Seeking020205 medical informaticsComputer science02 engineering and technologyUser requirements documentUser RequirementsWorld Wide Web03 medical and health sciencesSearch engine0302 clinical medicineStructured Data on the WebWeb page0202 electrical engineering electronic engineering information engineeringInformation retrievale-Health; Health Information Seeking; User Requirements; Language Complexity; Structured Data on the Web030212 general & internal medicineLanguage complexitySettore INF/01 - Informaticabusiness.industryWorld Wide WebLanguage ComplexityWork (electrical)HealthThe InternetE-HealthHealth informationbusinessMedical literature
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Heart failure risk reduction:hydrophilic or lipophilic statins?

2020

[No abstract]

Heart Failuremedicine.medical_specialtybusiness.industryMEDLINEmedicine.diseaseReduction (complexity)Text miningInternal medicineHeart failuremedicineCardiologyHumansPharmacology (medical)Hydroxymethylglutaryl-CoA Reductase InhibitorsCardiology and Cardiovascular MedicinebusinessHydrophobic and Hydrophilic InteractionsRisk Reduction Behavior
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Second-Order CASSCF Algorithm with the Cholesky Decomposition of the Two-Electron Integrals

2021

In this contribution, we present the implementation of a second-order complete active space–self-consistent field (CASSCF) algorithm in conjunction with the Cholesky decomposition of the two-electron repulsion integrals. The algorithm, called norm-extended optimization, guarantees convergence of the optimization, but it involves the full Hessian and is therefore computationally expensive. Coupling the second-order procedure with the Cholesky decomposition leads to a significant reduction in the computational cost, reduced memory requirements, and an improved parallel performance. As a result, CASSCF calculations of larger molecular systems become possible as a routine task. The performance …

Hessian matrixCouplingComputer scienceBasis functionField (mathematics)ArticleComputer Science ApplicationsReduction (complexity)symbols.namesakeConvergence (routing)symbolsBenchmark (computing)Physical and Theoretical ChemistryAlgorithmCholesky decompositionJournal of Chemical Theory and Computation
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