Search results for "VARIATION"

Invasion history and genetic population structure of riverine macroinvertebrates.

2005

Summary Macroinvertebrate communities of large rivers have experienced dramatic species turnovers in the last decades, which still go on. The analysis of genetic population structure plays a central role in understanding and predicting these biological invasions. Two points of view are considered: the influence of the invasion history on the genetic structuring and the potential implications of genetic structure for future invasibility. Expectations about selectively neutral genetic variation in simple invasion models are compared to case studies of amphipods and Dreissena. The genetic patterns of one amphipod species of the Gammarus fossarum complex yield strong evidence for a stepwise reg…

Triangular Bézier Surfaces of Minimal Area

2003

We study some methods of obtaining approximations to surfaces of minimal area with prescribed border using triangular Bezier patches. Some methods deduced from a variational principle are proposed and compared with some masks.

A variation on theorems of Jordan and Gluck

2006

Abstract Gluck proved that any finite group G has an abelian subgroup A such that | G : A | is bounded by a polynomial function of the largest degree of the complex irreducible characters of G . This improved on a previous bound of Isaacs and Passman. In this paper, we present a variation of this result that looks at the number of prime factors. All these results, in turn, may be seen as variations on the classical theorem of Jordan on linear groups.

Selection in captive populations

1986

We have briefly reviewed types of genetic variation and selection in the wild as contrasted with selection in captive populations, along with the objectives of captive breeding programs, before recommending selection procedures for the genetic management of captive populations. Although some inadvertent selection for tameness and adaptation to captive environments is inevitable in captive populations, any selection that is actively applied to captive populations should have clearly defined objectives. Much of the apparent disagreement about genetic management of captive populations probably stems from the varying objectives of different captive breeding programs. Objectives differ depending…

Syntactic Variance and Priming Effects in Translation

2016

The present work investigates the relationship between syntactic variation and priming in translation. It is based on the claim that languages share a common cognitive network of neural activity. When the source and target languages are solicited in a translation context, this shared network can lead to facilitation effects, so-called priming effects. We suggest that priming is a default setting in translation, a special case of language use where source and target languages are constantly co-activated. Such priming effects are not restricted to lexical elements, but do also occur on the syntactic level. We tested these hypotheses with translation data from the TPR database, more specifical…

Copy number variation and missense mutations of the agouti signaling protein (ASIP) gene in goat breeds with different coat colors.

2009

In goats, classical genetic studies reported a large number of alleles at the Agouti locus with effects on coat color and pattern distribution. From these early studies, the dominant A(Wt) (white/tan) allele was suggested to cause the white color of the Saanen breed. Here, we sequenced the coding region of the goat ASIP gene in 6 goat breeds (Girgentana, Maltese, Derivata di Siria, Murciano-Granadina, Camosciata delle Alpi, and Saanen), with different coat colors and patterns. Five single nucleotide polymorphisms (SNPs) were identified, 3 of which caused missense mutations in conserved positions of the cysteine-rich carboxy-terminal domain of the protein (p.Ala96Gly, p.Cys126Gly, and p.Val1…

Variational differential inclusions without ellipticity condition

2020

The paper sets forth a new type of variational problem without any ellipticity or monotonicity condition. A prototype is a differential inclusion whose driving operator is the competing weighted $(p,q)$-Laplacian $-\Delta_p u+\mu\Delta_q u$ with $\mu\in \mathbb{R}$. Local and nonlocal boundary value problems fitting into this nonstandard setting are examined.

Variation and change in English resultative constructions

2010

AbstractThe system of English resultative constructions is in a state of flux characterized by variation between two of its most prominent competitors,way-constructions as inShe worked herwayto the topand reflexive structures as inShe worked herselfto the top.Although this competition has occasionally been addressed in the literature (cf. Jackendoff, 1990:213; Kirchner, 1951:158; Salkoff, 1988:54ff.), the present findings reveal that the long-standing rivalry between these structures has resulted in an increased use of theway-construction at the expense of reflexive structures. In addition, the coexistence ofway-constructions with semantically overlapping reflexive structures eventually cul…

Local Total Variation Bounded Methods for Hyperbolic Conservation Laws

2003

A Fly-Inspired Mushroom Bodies Model for Sensory-Motor Control Through Sequence and Subsequence Learning

2016

Classification and sequence learning are relevant capabilities used by living beings to extract complex information from the environment for behavioral control. The insect world is full of examples where the presentation time of specific stimuli shapes the behavioral response. On the basis of previously developed neural models, inspired by Drosophila melanogaster, a new architecture for classification and sequence learning is here presented under the perspective of the Neural Reuse theory. Classification of relevant input stimuli is performed through resonant neurons, activated by the complex dynamics generated in a lattice of recurrent spiking neurons modeling the insect Mushroom Bodies n…