scholarly journals Generating and Enumerating 321-Avoiding and Skew-Merged Simple Permutations

10.37236/3058 ◽  
2013 ◽  
Vol 20 (2) ◽  
Author(s):  
Michael H. Albert ◽  
Vincent Vatter
Keyword(s):  
Uniform Method ◽  
Working Backwards

The simple permutations in two permutation classes --- the $321$-avoiding permutations and the skew-merged permutations --- are enumerated using a uniform method. In both cases, these enumerations were known implicitly, by working backwards from the enumeration of the class, but the simple permutations had not been enumerated explicitly. In particular, the enumeration of the simple skew-merged permutations leads to the first truly structural enumeration of this class as a whole. The extension of this method to a wider collection of classes namely grid classes of infinite paths is discussed.

scholarly journals Cross-linguistic influence in simultaneous and early sequential bilingual children: a meta-analysis

2021 ◽  
pp. 1-33
Author(s):  
Chantal VAN DIJK ◽  
Elise VAN WONDEREN ◽  
Elly KOUTAMANIS ◽  
Gerrit Jan KOOTSTRA ◽  
Ton DIJKSTRA ◽  
...  
Keyword(s):  
Effect Size ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Uniform Method ◽  
Bilingual Children ◽  
Average Effect ◽  
Language Dominance ◽  
Average Effect Size ◽  
Comprehensive Theory ◽  
Bilingual Development

Abstract Although cross-linguistic influence at the level of morphosyntax is one of the most intensively studied topics in child bilingualism, the circumstances under which it occurs remain unclear. In this meta-analysis, we measured the effect size of cross-linguistic influence and systematically assessed its predictors in 750 simultaneous and early sequential bilingual children in 17 unique language combinations across 26 experimental studies. We found a significant small to moderate average effect size of cross-linguistic influence, indicating that cross-linguistic influence is part and parcel of bilingual development. Language dominance, operationalized as societal language, was a significant predictor of cross-linguistic influence, whereas surface overlap, language domain and age were not. Perhaps an even more important finding was that definitions and operationalisations of cross-linguistic influence and its predictors varied considerably between studies. This could explain the absence of a comprehensive theory in the field. To solve this issue, we argue for a more uniform method of studying cross-linguistic influence.

scholarly journals Dem Anfang auf der Spur — die Suche nach DNA-Replikationsursprüngen

BIOspektrum ◽  
2021 ◽  
Vol 27 (3) ◽  
pp. 246-249
Author(s):  
Elisabeth Kruse ◽  
Stephan Hamperl
Keyword(s):  
Cell Division ◽  
Dna Synthesis ◽  
Genomic Dna ◽  
Genetic Material ◽  
Uniform Method ◽  
Replication Origins ◽  
Daughter Cells ◽  
Origins Of Replication ◽  
Mammalian Genomes ◽  
Comprehensive Manner

AbstractTimely and accurate duplication of DNA prior to cell division is a prerequisite for propagation of the genetic material to both daughter cells. DNA synthesis initiates at discrete sites, termed replication origins, and proceeds in a bidirectional manner until all genomic DNA is replicated. Despite the fundamental nature of these events, a uniform method that identifies origins of replication in a comprehensive manner is still missing. Here, we present currently available and discuss new approaches to map replication origins in mammalian genomes.

Ambidexterity [L'Homme droit et l'Homme gauche: les Ambidextres]. (Revue philosophique, October, 1901.) Biervliet, J. J. van.

1902 ◽  
Vol 48 (201) ◽  
pp. 348-349
Author(s):  
Havelock Ellis
Keyword(s):  
Uniform Method ◽  
Careful Study ◽  
The Face ◽  
The Right ◽  
Two Sides ◽  
Careful Investigation

Professor van Biervliet has now completed his very careful study of right-sidedness and left-sidedness (already summarised in the Journal) by a still more careful investigation of ambidextrous persons. In the first place by photography, according to a special and uniform method, he finds that in the ambidextrous the two sides of the face, as well as the arms, are fairly alike, the face being slightly more developed on the right side, as among left-sided people, but not in so marked a degree. They occupy much the same position, indeed, throughout the investigation. When compared with right-sided and left-sided people as regards sensory acuteness, it is found that while the right-sided have predominant sensory acuteness on the right side, both the left-sided and the ambidextrous can see further, hear better, possess more acute tactile and muscular sense, on the left side, so that ambidexterity may be regarded as a variety of left-sidedness of more symmetrical anatomical type. In all respects the ambidextrous almost or quite resembled the left-sided.

scholarly journals Massive stars in their death throes

2008 ◽  
Vol 366 (1884) ◽  
pp. 4441-4452 ◽  
Author(s):  
John J Eldridge
Keyword(s):  
Stellar Evolution ◽  
Massive Stars ◽  
Evolution Theory ◽  
Luminous Blue Variables ◽  
Show Evidence ◽  
Red Supergiants ◽  
Working Backwards

The study of the stars that explode as supernovae used to be a forensic study, working backwards from the remnants of the star. This changed in 1987 when the first progenitor star was identified in pre-explosion images. Currently, there are eight detected progenitors with another 21 non-detections, for which only a limit on the pre-explosion luminosity can be placed. This new avenue of supernova research has led to many interesting conclusions, most importantly that the progenitors of the most common supernovae, type IIP, are red supergiants, as theory has long predicted. However, no progenitors have been detected thus far for the hydrogen-free type Ib/c supernovae, which, given the expected progenitors, is an unlikely result. Also, observations have begun to show evidence that luminous blue variables, which are among the most massive stars, may directly explode as supernovae. These results contradict the current stellar evolution theory. This suggests that we may need to update our understanding.

A Uniform Method for Determining Angular Accelerations in Mechanisms

1946 ◽  
Vol 13 (1) ◽  
pp. A41-A44
Author(s):  
L. R. Koenig
Keyword(s):  
Full Advantage ◽  
Velocity Vector ◽  
Angular Acceleration ◽  
Uniform Method ◽  
Insight Into ◽  
Considerable Insight

Abstract The purpose of this paper is to disclose a more reliable and uniform method, applicable to mechanisms in general, for determining directly the angular accelerations of the constituent links. The method completely suffices where the determination of angular accelerations is the end in view. Although it is independent of normal, tangential, and total accelerations of points on the links, reliable determinations of such accelerations are considerably facilitated with the aid of the acquired angular accelerations. Angular-acceleration problems may be solved with increased assurance because; (a) only velocity-vector considerations are required in the necessary kinematic layouts; (b) full advantage may be taken of the process of inversion in simplifying velocity-vector layouts, which is not possible when acceleration vectors are employed; and (c) the method gives considerable insight into the effects of the various factors controlling the angular accelerations.

Working Backwards? Using Simulation to Sort Out Empirical Inconsistencies

2013 ◽  
pp. 229-250
Author(s):  
Robert Erikson ◽  
Aaron Strauss ◽  
Michael Bruter
Keyword(s):  
Working Backwards
Sign in / Sign up

Export Citation Format

Share Document