On the Use of the Time Axis for Ecological Separation: Diel Rhythms as an Evolutionary Constraint

2001 ◽  
Vol 158 (4) ◽  
pp. 451
Author(s):  
Kronfeld-Schor ◽  
Dayan ◽  
Elvert ◽  
Haim ◽  
Zisapel ◽  
...  
Keyword(s):  
Evolutionary Constraint ◽  
Time Axis ◽  
Diel Rhythms ◽  
Ecological Separation

On the Use of the Time Axis for Ecological Separation: Diel Rhythms as an Evolutionary Constraint

2001 ◽  
Vol 158 (4) ◽  
pp. 451-457 ◽  
Author(s):  
Noga Kronfeld‐Schor ◽  
Tamar Dayan ◽  
Ralf Elvert ◽  
Abraham Haim ◽  
Nava Zisapel ◽  
...  
Keyword(s):  
Evolutionary Constraint ◽  
Time Axis ◽  
Diel Rhythms ◽  
Ecological Separation

A comparative analysis of the Slovenian particles še and že against the background of the Russian language

2020 ◽  
pp. 324-345
Author(s):  
Mariya L. Kuleshоva ◽  
Keyword(s):  
Nineteenth Century ◽  
Comparative Analysis ◽  
Russian Language ◽  
Time Axis ◽  
Temporal Modifiers ◽  
The Russian Language ◽  
Negative Form

The article compares the Slovenian particles še and že mainly with the Russian particles еще and уже. Unlike the Russian particle уже, the Slovenian particle že cannot be combined with the negative form of the verb: instead of it, the adverb več is used in such contexts. The most subtle differences between the Slovenian and Russian languages are found in the combinations of še and že with temporal modifiers, where the so-called “plot time” is characteristic of the Slovenian language. The event is interpreted as localized on the time axis, not from the perspective of the «speaker’s time», which is manifested in the possibility of using že in such contexts as umrl je že v devetnajstem stoletju (he died in the nineteenth century already). Moreover, že is not able to express the meaning ‘no earlier / no later than’, because the particle šele replaces it in this function. The author comes to the conclusion that Slovenian particles are more widely used as modal than their Russian equivalents. The particle še has numerous intensifying functions, correlating with the functions of Russian particles даже, еще и, и. The particle že can be used in the same way as two Russian words уже and уж. In contrast to уж, že does not always express displeasure and can add the meaning of a concession to the statement.

Modeling mass transfer and substrate utilization in the boundary layer of biofilm systems

1998 ◽  
Vol 37 (4-5) ◽  
pp. 139-147 ◽  
Author(s):  
Harald Horn ◽  
Dietmar C. Hempel
Keyword(s):  
Boundary Layer ◽  
Mass Transfer ◽  
Reynolds Number ◽  
Film Theory ◽  
Substrate Utilization ◽  
The Other ◽  
Concentration Profiles ◽  
Hydrodynamic Conditions ◽  
Time Axis ◽  
Transfer Coefficients

The use of microelectrodes in biofilm research allows a better understanding of intrinsic biofilm processes. Little is known about mass transfer and substrate utilization in the boundary layer of biofilm systems. One possible description of mass transfer can be obtained by mass transfer coefficients, both on the basis of the stagnant film theory or with the Sherwood number. This approach is rather formal and not quite correct when the heterogeneity of the biofilm surface structure is taken into account. It could be shown that substrate loading is a major factor in the description of the development of the density. On the other hand, the time axis is an important factor which has to be considered when concentration profiles in biofilm systems are discussed. Finally, hydrodynamic conditions become important for the development of the biofilm surface when the Reynolds number increases above the range of 3000-4000.

scholarly journals Serial disparity in the carnivoran backbone unveils a complex adaptive role in metameric evolution

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Borja Figueirido ◽  
Alberto Martín-Serra ◽  
Alejandro Pérez-Ramos ◽  
David Velasco ◽  
Francisco J. Pastor ◽  
...  
Keyword(s):  
Evolutionary Constraint ◽  
Phenotypic Evolution ◽  
Quantitative Studies ◽  
Thoracolumbar Region ◽  
Complex Adaptive ◽  
Dimensional Shape ◽  
A Chain ◽  
Low Dimensional ◽  
Adaptive Role ◽  
Shape Changes

AbstractOrganisms comprise multiple interacting parts, but few quantitative studies have analysed multi-element systems, limiting understanding of phenotypic evolution. We investigate how disparity of vertebral morphology varies along the axial column of mammalian carnivores — a chain of 27 subunits — and the extent to which morphological variation have been structured by evolutionary constraints and locomotory adaptation. We find that lumbars and posterior thoracics exhibit high individual disparity but low serial differentiation. They are pervasively recruited into locomotory functions and exhibit relaxed evolutionary constraint. More anterior vertebrae also show signals of locomotory adaptation, but nevertheless have low individual disparity and constrained patterns of evolution, characterised by low-dimensional shape changes. Our findings demonstrate the importance of the thoracolumbar region as an innovation enabling evolutionary versatility of mammalian locomotion. Moreover, they underscore the complexity of phenotypic macroevolution of multi-element systems and that the strength of ecomorphological signal does not have a predictable influence on macroevolutionary outcomes.

scholarly journals Whole-Genome Sequence Analysis of Pseudorabies Virus Clinical Isolates from Pigs in China between 2012 and 2017 in China

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1322
Author(s):  
Ruiming Hu ◽  
Leyi Wang ◽  
Qingyun Liu ◽  
Lin Hua ◽  
Xi Huang ◽  
...  
Keyword(s):  
Selection Pressure ◽  
Pseudorabies Virus ◽  
Viral Evolution ◽  
Infectious Agent ◽  
Genomic Diversity ◽  
Whole Genome Sequence ◽  
Evolutionary Constraint ◽  
The Novel ◽  
Novel Variants ◽  
Pressure Analysis

Pseudorabies virus (PRV) is an economically significant swine infectious agent. A PRV outbreak took place in China in 2011 with novel virulent variants. Although the association of viral genomic variability with pathogenicity is not fully confirmed, the knowledge concerning PRV genomic diversity and evolution is still limited. Here, we sequenced 54 genomes of novel PRV variants isolated in China from 2012 to 2017. Phylogenetic analysis revealed that China strains and US/Europe strains were classified into two separate genotypes. PRV strains isolated from 2012 to 2017 in China are highly related to each other and genetically close to classic China strains such as Ea, Fa, and SC. RDP analysis revealed 23 recombination events within novel PRV variants, indicating that recombination contributes significantly to the viral evolution. The selection pressure analysis indicated that most ORFs were under evolutionary constraint, and 19 amino acid residue sites in 15 ORFs were identified under positive selection. Additionally, 37 unique mutations were identified in 19 ORFs, which distinguish the novel variants from classic strains. Overall, our study suggested that novel PRV variants might evolve from classical PRV strains through point mutation and recombination mechanisms.

scholarly journals Including distorted specimens in allometric studies: linear mixed models account for deformation

2021 ◽  
Author(s):  
Brenen M Wynd ◽  
Josef C Uyeda ◽  
Sterling J Nesbitt
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Major Axis ◽  
Ordinary Least Squares ◽  
Evolutionary Constraint ◽  
Body Parts ◽  
Least Squares Regression ◽  
Full Dataset ◽  
Residual Variation ◽  
Cranial Measurements

Abstract Allometry—patterns of relative change in body parts—is a staple for examining how clades exhibit scaling patterns representative of evolutionary constraint on phenotype, or quantifying patterns of ontogenetic growth within a species. Reconstructing allometries from ontogenetic series is one of the few methods available to reconstruct growth in fossil specimens. However, many fossil specimens are deformed (twisted, flattened, displaced bones) during fossilization, changing their original morphology in unpredictable and sometimes undecipherable ways. To mitigate against post burial changes, paleontologists typically remove clearly distorted measurements from analyses. However, this can potentially remove evidence of individual variation and limits the number of samples amenable to study, which can negatively impact allometric reconstructions. Ordinary least squares regression (OLS) and major axis regression are common methods for estimating allometry, but they assume constant levels of residual variation across specimens, which is unlikely to be true when including both distorted and undistorted specimens. Alternatively, a generalized linear mixed model (GLMM) can attribute additional variation in a model (e.g., fixed or random effects). We performed a simulation study based on a empirical analysis of the extinct cynodont, Exaeretodon argentinus, to test the efficacy of a GLMM on allometric data. We found that GLMMs estimate the allometry using a full dataset better than simply using only non-distorted data. We apply our approach on two empirical datasets, cranial measurements of actual specimens of E. argentinus (n = 16) and femoral measurements of the dinosaur Tawa hallae (n = 26). Taken together, our study suggests that a GLMM is better able to reconstruct patterns of allometry over an OLS in datasets comprised of extinct forms and should be standard protocol for anyone using distorted specimens.

Measurement of Dynamic Strain

1943 ◽  
Vol 10 (2) ◽  
pp. A85-A92
Author(s):  
C. O. Dohrenwend ◽  
W. R. Mehaffey
Keyword(s):  
High Speed ◽  
Shock Loading ◽  
Low Frequency ◽  
Dynamic Strain ◽  
Time Axis ◽  
Low Frequencies ◽  
Strain Measurements ◽  
Moving Vehicles ◽  
Machine Parts ◽  
Dynamic Strains

Abstract The measurement of dynamic strains of both high and low frequency give rise to a variety of problems in instrumentation. Two types of equipment and circuits designed and used by the authors are discussed in detail. The first type based on the amplitude-modulated method is for low frequencies from zero to about 15 per cent of the carrier frequency of 1025 cycles per sec. The equipment has application to strain measurements varying from static values to those produced in moving vehicles, various machine parts, structures such as crane bridges, in fact all strain measurements where the frequency is 150 cycles per sec or less. The second type of equipment discussed is a potentiometer type and is for high-frequency strain measurements from 100 cycles per sec to 8000 cycles per sec. This high-speed equipment is conveniently used for impact strain, such as produced in hammer blows, shock loading, forging equipment, and impact-factor determination. Both units are designed to be used with a cathode-ray oscillograph which lends itself to a variety of recording methods. The methods discussed include both the type where the time axis is obtained by sweeping the oscilloscope beam on a stationary film and where the time axis is obtained mechanically.

Recently amplified Alu family members share a common parental Alu sequence

1988 ◽  
Vol 8 (10) ◽  
pp. 4566-4569
Author(s):  
P L Deininger ◽  
V K Slagel
Keyword(s):  
Family Members ◽  
Evolutionary Constraint ◽  
Alu Sequence ◽  
Amplification Process

Three of the most recently inserted primate Alu family members are exceptionally closely related. Therefore, one, or a few, Alu family members are dominating the amplification process and the vast majority are not actively involved in retroposition. Although individual Alu family members are not under any apparent evolutionary constraint, the sequences of these active members are being moderately conserved.

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