Search results for "Null"
showing 10 items of 396 documents
Accelerated Evolution of Fetuin-A (FETUA, also AHSG) is Driven by Positive Darwinian Selection, not GC-Biased Gene Conversion
2009
article i nfo Human Fetuin-A (FETUA, also termed AHSG) is a serum protein composed of two cystatin-like domains D1 and D2 of together 235 amino acids (aa) and an unrelated domain D3 of 114 aa. Though the protein plays a role in diverse physiological and pathological processes, comparably little is known about sequence evolution of FETUA. We therefore analyzed its molecular evolution on the basis of coding sequences of 16 primate species. Ratios of non-synonymous to synonymous substitution rates (dn/ds= ω) suggest that a previously reported acceleration of sequence evolution of exon 7, which encodes domain D3, is driven by positive selection instead of neutral evolution. Irrespective of the …
Primers for nine microsatellite loci in the hermaphroditic snailLymnaea stagnalis
2003
Variation in and amplification conditions for nine polymorphic microsatellite loci identified from Lymnaea stagnalis , a hermaphroditic pulmonate snail, are described. Eight populations from central Finland were studied, which varied in terms of both observed polymorphism and heterozygosity. The number of alleles at each locus is moderate (two to seven), except for one exceptional locus having 16 alleles, and for which null alleles are possible. There is no evidence for genotypic disequilibrium in the populations for all pairs of loci. Heterozygosity levels are indicative of outcrossing in L. stagnalis , whose mating system will be characterized further using these markers.
New alleles and mutational events at 14 STR loci from different German populations.
2007
The molecular origin of DNA mutations and the mutation rates were analyzed at 14 short tandem repeat (STR) loci with samples from trio cases derived from 10 different German population samples. STR loci comprised of D2S1360, D3S1744, D4S2366, D5S2500, D6S474, D7S1517, D8S1132, D10S2325, D12S391, D18S51, D19S246, D20S480, D21S226, and D22S689. In a total of 488 meioses, 16 isolated genetic inconsistencies in 8 different STRs were observed, whereas no mutations were found at the other loci. The data of five mutations suggested the presence of silent or null alleles due to sequence variation in primer binding site. This could be confirmed for four suspected cases by the use of alternative prim…
Isolation and characterization of 10 highly polymorphic di- and trinucleotide microsatellite markers in the mayfly Ameletus inopinatus (Ephemeroptera…
2008
We describe the isolation of ten polymorphic microsatellite loci from the mayfly Ameletus inopinatus. Loci had di- or trinucleotide repeat motifs and were highly variable with three to 17 alleles (mean = 7.15). Observed heterozygosity ranged from 0.143 to 0.905. One locus (Ami_202) showed significant deviation from Hardy–Weinberg equilibrium in one population, but no evidence for null alleles. One locus (Ami_73) was significantly linked with three other loci. The remaining nine loci should prove highly informative for population genetic studies.
Isolation and characterization of 11 polymorphic trinucleotide microsatellite markers in the stonefly Arcynopteryx compacta (Plecoptera: Perlodidae).
2011
We describe the isolation of 11 polymorphic trinucleotide microsatellite loci from the stonefly Arcynopteryx compacta. Loci were highly variable with 3 to 14 alleles (mean = 6.45). Observed heterozygosity ranged from 0 to 0.867. Seven loci showed significant deviation from Hardy–Weinberg equilibrium across both populations. There was no evidence for null alleles, and thus, Hardy–Weinberg departures could have resulted from genetic structure between populations or subpopulations. No linkage between loci was found. The 11 loci should prove highly informative for population genetic studies.
Necessidade do controlar de oficio as cláusulas abusivas nos contratos com consumidores: Estudo comparado com o sistema espanhol
2016
Las autoridades europeas abogan por dotar al juez de mayores facultades para controlar ex officio la inclusión de cláusulas abusivas en los contratos de adhesión celebrados entre empresarios y consumidores. Una línea jurisprudencial incorporada en España, mejorando así la tutela y protección de los derechos e intereses de los consumidores. No obstante, países como Uruguay no contemplan esta posibilidad, impidiendo al juez realizar un control de contenido cuando no haya sido solicitado por las partes puesto que se cuestiona su anulación debido a la propia naturaleza de la nulidad. En el presente artículo analizamos las diferentes regulaciones de las cláusulas abusivas en los ordenamientos es…
Zero rest-mass fields and the Newman-Penrose constants on flat space
2020
Zero rest-mass fields of spin 1 (the electromagnetic field) and spin 2 propagating on flat space and their corresponding Newman-Penrose (NP) constants are studied near spatial infinity. The aim of this analysis is to clarify the correspondence between data for these fields on a spacelike hypersurface and the value of their corresponding NP constants at future and past null infinity. To do so, Friedrich's framework of the cylinder at spatial infinity is employed to show that, expanding the initial data in terms spherical harmonics and powers of the geodesic spatial distance $\rho$ to spatial infinity, the NP constants correspond to the data for the second highest possible spherical harmonic …
Granular chains for the assessment of thermal stress in slender structures
2015
Slender beams subjected to compressive stress are common in civil and mechanical engineering. The rapid in-situ measurement of this stress may prevent structural anomalies. In this paper, we describe the coupling mechanism between highly nonlinear solitary waves (HNSWs) propagating along an L-shaped granular system and a beam in contact with the granular medium. We evaluate the use of HNSWs as a tool to measure stress in thermally loaded structures and to estimate the neutral temperature, i.e. the temperature at which this stress is null. We investigated numerically and experimentally one and two L-shaped chains of spherical particles in contact with a prismatic beam subjected to heat. We f…
Beyond the functional matrix hypothesis: a network null model of human skull growth for the formation of bone articulations.
2014
Craniofacial sutures and synchondroses form the boundaries among bones in the human skull, providing functional, developmental and evolutionary information. Bone articulations in the skull arise due to interactions between genetic regulatory mechanisms and epigenetic factors such as functional matrices (soft tissues and cranial cavities), which mediate bone growth. These matrices are largely acknowledged for their influence on shaping the bones of the skull; however, it is not fully understood to what extent functional matrices mediate the formation of bone articulations. Aiming to identify whether or not functional matrices are key developmental factors guiding the formation of bone articu…
Time Series Momentum in the US Stock Market: Empirical Evidence and Theoretical Implications
2020
There is much controversy in the academic literature on the presence of short-term trends in financial markets and the trend-following strategy's profitability. This paper restricts its attention to the study of time-series momentum (TSMOM) in the US stock market. The paper aims to suggest answers to several important questions regarding TSMOM and to explain the existing controversy. Our answer to the question, whether short-term trends exist, is strongly affirmative. For the first time, we suppose that the returns follow a p-order autoregressive process with p>1 and evaluate this process's parameters. Fairly accurate knowledge of the momentum generating process allows us to provide analyti…