The Arrangement of Bristles in Drosophila1

Development ◽  
1961 ◽  
Vol 9 (4) ◽  
pp. 661-672
Author(s):  
J. Maynard Smith ◽  
K. C. Sondhi
Keyword(s):  
Linear Series ◽  
Two Dimensional ◽  
Constant Number ◽  
Geometrical Complexity ◽  
Hypodermal Cell ◽  
The Family ◽  
Illustrative Material

Much of the geometrical complexity of animals and plants arises by the repetition of similar structures, often in a pattern which is constant for a species. In an earlier paper (Maynard Smith, 1960) some of the mechanisms whereby a constant number of structures in a linear series might arise were discussed. In this paper an attempt is made to extend the argument to cases where such structures are arranged in two-dimensional patterns on a surface, using the arrangement of bristles in Drosophila as illustrative material. The bristles of Drosophila fall into two main classes, the microchaetes and the macrochaetes. A bristle of either type, together with its associated sensory nervecell, arises by the division of a single hypodermal cell. The macrochaetes are larger, and constant in number and position in a species, and in most cases throughout the family Drosophilidae.

scholarly journals A Markov model for Selmer ranks in families of twists

2014 ◽  
Vol 150 (7) ◽  
pp. 1077-1106 ◽  
Author(s):  
Zev Klagsbrun ◽  
Barry Mazur ◽  
Karl Rubin
Keyword(s):  
Markov Process ◽  
Markov Model ◽  
Elliptic Curve ◽  
Arbitrary Number ◽  
Equilibrium Distribution ◽  
Two Dimensional ◽  
Absolute Galois Group ◽  
Quadratic Twists ◽  
The Family ◽  
Positive Integers

AbstractWe study the distribution of 2-Selmer ranks in the family of quadratic twists of an elliptic curve $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}E$ over an arbitrary number field $K$. Under the assumption that ${\rm Gal}(K(E[2])/K) \ {\cong }\ S_3$, we show that the density (counted in a nonstandard way) of twists with Selmer rank $r$ exists for all positive integers $r$, and is given via an equilibrium distribution, depending only on a single parameter (the ‘disparity’), of a certain Markov process that is itself independent of $E$ and $K$. More generally, our results also apply to $p$-Selmer ranks of twists of two-dimensional self-dual ${\bf F}_p$-representations of the absolute Galois group of $K$ by characters of order $p$.

New Hopane Triterpenoids From Lichens in the Family Physiaceae

1989 ◽  
Vol 42 (8) ◽  
pp. 1415 ◽  
Author(s):  
AL Wilkins ◽  
JA Elix ◽  
KL Gaul ◽  
R Moberg
Keyword(s):  
Methyl Ester ◽  
Natural Occurrence ◽  
Two Dimensional ◽  
Triterpene Acid ◽  
The Family ◽  
First Time

Three new hopane triterpenes have been isolated from lichens of the family Physciaceae. Two of the triterpenes, 22-hydroxyhopan-6-one (2) and 6 α-acetoxyhopan-22-ol (1b), have been characterized previously but their natural occurrence is reported for the first time, while a new triterpene acid [ aipolic acid (1c)], was isolated and characterized as the corresponding methyl ester. One- and two-dimensional 1H-1H and 13C-lH correlated n.m.r. studies have revealed methyl aipolate to be methyl 6#945;-acetoxy-22-hydroxyhopan-25-oate (1d).

A CHARACTERIZATION OF RECOGNIZABLE PICTURE LANGUAGES

1994 ◽  
Vol 08 (02) ◽  
pp. 501-508 ◽  
Author(s):  
KATSUSHI INOUE ◽  
ITSUO TAKANAMI
Keyword(s):  
Finite Automata ◽  
Two Dimensional ◽  
Open Problems ◽  
Nondeterministic Finite Automata ◽  
Letter Alphabet ◽  
The Family ◽  
On Line ◽  
Picture Languages

This paper first shows that REC, the family of recognizable picture languages in Giammarresi and Restivo,3 is equal to the family of picture languages accepted by two-dimensional on-line tessellation acceptors in Inoue and Nakamura.5 By using this result, we then solve open problems in Giammarresi and Restivo,3 and show that (i) REC is not closed under complementation, and (ii) REC properly contains the family of picture languages accepted by two-dimensional nondeterministic finite automata even over a one letter alphabet.

Bifurcations of one- and two-dimensional maps

1984 ◽  
Vol 311 (1515) ◽  
pp. 43-102 ◽  
Keyword(s):  
Periodic Orbits ◽  
Period Doubling ◽  
Jacobian Determinant ◽  
Two Dimensional ◽  
Hénon Map ◽  
Stable And Unstable Manifolds ◽  
Henon Map ◽  
One Dimensional ◽  
The Family ◽  
Area Preserving

We study the qualitative dynamics of two-parameter families of planar maps of the form F^e(x, y) = (y, -ex+f(y)), where f :R -> R is a C 3 map with a single critical point and negative Schwarzian derivative. The prototype of such maps is the family f(y) = u —y 2 or (in different coordinates) f(y) = Ay(1 —y), in which case F^ e is the Henon map. The maps F e have constant Jacobian determinant e and, as e -> 0, collapse to the family f^. The behaviour of such one-dimensional families is quite well understood, and we are able to use their bifurcation structures and information on their non-wandering sets to obtain results on both local and global bifurcations of F/ ue , for small e . Moreover, we are able to extend these results to the area preserving family F/u. 1 , thereby obtaining (partial) bifurcation sets in the (/u, e)-plane. Among our conclusions we find that the bifurcation sequence for periodic orbits, which is restricted by Sarkovskii’s theorem and the kneading theory for one-dimensional maps, is quite different for two-dimensional families. In particular, certain periodic orbits that appear at the end of the one-dimensional sequence appear at the beginning of the area preserving sequence, and infinitely many families of saddle node and period doubling bifurcation curves cross each other in the ( /u, e ) -parameter plane between e = 0 and e = 1. We obtain these results from a study of the homoclinic bifurcations (tangencies of stable and unstable manifolds) of F /u.e and of the associated sequences of periodic bifurcations that accumulate on them. We illustrate our results with some numerical computations for the orientation-preserving Henon map.

On the limit of spectral measures associated to a test configuration of a polarized Kähler manifold

2016 ◽  
Vol 2016 (713) ◽  
Author(s):  
Tomoyuki Hisamoto
Keyword(s):  
Integral Formula ◽  
Kähler Manifold ◽  
Linear Series ◽  
Spectral Measures ◽  
Test Configuration ◽  
Kahler Manifold ◽  
The Family ◽  
Graded Linear Series

AbstractWe apply our integral formula of volumes to the family of graded linear series constructed from any test configuration. This solves the conjecture raised by Witt Nyström to the effect that the sequence of spectral measures for the induced ℂ

From two-dimensional nano-sheets to roll-up structures: expanding the family of nanoscroll

2017 ◽  
Vol 28 (38) ◽  
pp. 385704 ◽  
Author(s):  
Zhigang Liu ◽  
Junfeng Gao ◽  
Gang Zhang ◽  
Yuan Cheng ◽  
Yong-Wei Zhang
Keyword(s):  
Two Dimensional ◽  
The Family

scholarly journals Charge density wave phenomena in the family of two dimensional monophosphate tungsten bronzes : (PO2)4(WO3)2 m

1993 ◽  
Vol 03 (C2) ◽  
pp. C2-133-C2-136 ◽  
Author(s):  
P. FOURY ◽  
J. P. POUGET ◽  
Z. S. TEWELDEMEDHIN ◽  
E. WANG ◽  
M. GREENBLATT ◽  
...  
Keyword(s):  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave ◽  
Two Dimensional ◽  
The Family ◽  
Wave Phenomena

scholarly journals Optoelectrical Nanomechanical Resonators Made From Multilayered 2D Materials

2021 ◽  
Author(s):  
Joshoua Condicion Esmenda ◽  
Myrron Albert Callera Aguila ◽  
Jyh-Yang Wang ◽  
Teik-Hui Lee ◽  
Yen-Chun Chen ◽  
...  
Keyword(s):  
Hybrid Systems ◽  
2D Materials ◽  
Quantum Systems ◽  
Optimal Choice ◽  
Two Dimensional ◽  
Quantum Communications ◽  
Nanomechanical Resonator ◽  
Nanomechanical Resonators ◽  
The Family ◽  
Low Mass

Abstract Studies involving nanomechanical motion have evolved from its detection and understanding of its fundamental aspects to its promising practical utility as an integral component of hybrid systems. Nanomechanical resonators’ indispensable role as transducers between optical and microwave fields in hybrid systems, such as quantum communications interface, have elevated their importance in recent years. It is therefore crucial to determine which among the family of nanomechanical resonators is more suitable for this role. Most of the studies revolve around nanomechanical resonators of ultrathin structures because of their inherently large mechanical amplitude due to their very low mass. Here, we argue that the underutilized nanomechanical resonators made from multilayered two-dimensional (2D) materials are the better fit for this role because of their comparable electrostatic tunability and larger optomechanical responsivity. To show this, we first demonstrate the electrostatic tunability of mechanical modes of a multilayered nanomechanical resonator made from graphite. We also show that the optomechanical responsivity of multilayered devices will always be superior as compared to the few-layer devices. Finally, by using the multilayered model and comparing this device with the reported ones, we find that the electrostatic tunability of devices of intermediate thickness is not significantly lower than that of ultrathin ones. Together with the practicality in terms of fabrication ease and design predictability, we contend that multilayered 2D nanomechanical resonators are the optimal choice for the electromagnetic interface in integrated quantum systems.

scholarly journals Fotografie rodziny Mierów i Jędrzejowiczów z zespołu „Archiwum Podworskie Mierów-Jędrzejowiczów w Staromieściu” w Archiwum Państwowym w Rzeszowie

2020 ◽  
Vol 16 (3) ◽  
pp. 123-140
Author(s):  
Sabina Rejman ◽  
Keyword(s):  
The State ◽  
State Archive ◽  
Historical Source ◽  
The Family ◽  
Family Home ◽  
The City ◽  
Illustrative Material

According to archivists a photograph can be both an illustrative material and a historical source. But still there is no handbook which can describe all aspects connected with photograpfic documentation. In the State Archive in Rzeszów (complex “Archiwum Podworskie Mierów-Jędrzejowiczów w Staromieściu”) there is the small separated collection of photographies. They present: portrait photos (Tytus Jan Mateusz hrabia Mier, Henryka z Mierów Komorowska) and watches with a miniature portrait of Jan hrabia Mier; postcards with photos of military manoeuvres; the portrait photo (Lubina z Rogoyskich Mierowa) and a photo for official documents (Jan Feliks Jędrzejowicz). The family of Mier which had Scotish and Calvinist roots and the family of Jędrzejowicz of Armenian and merchant origin were connected by the marriage contracted in 1878 in Vienna between Adam Jędrzejowicz (1847–1924), the son of Jan Kanty and Maria (maiden name Straszewska) from Zaczernie and Gabriela Felicja (maiden name Mier) (1850–1939), the daughter of Feliks and Felicja, divorced with Zdzisław Tyszkiewicz, the heir to landed property of Kolbuszowa. After the wedding Staromieście became their family home (now it is within the city limits of Rzeszów). Then Jan Feliks (1879–1942), the only son of this couple, managed the estate. Photographs provide valuable information both in the textual (notes connected with presented on photos persons, things, events) and illustrative stratum.

Robust IMEX Schemes for Solving Two-Dimensional Reaction–Diffusion Models

2015 ◽  
Vol 16 (6) ◽  
pp. 271-284 ◽  
Author(s):  
Kolade M. Owolabi
Keyword(s):  
Differential Equations ◽  
Linear Part ◽  
Reaction Diffusion ◽  
Formation Processes ◽  
Two Dimensional ◽  
Numerical Examples ◽  
Nonlinear Part ◽  
Linear Partial Differential Equations ◽  
The Family ◽  
Imex Schemes

AbstractIn this paper, numerical simulations of two-dimensional reaction–diffusion (for single and multi-species) models are considered for pattern formation processes. The nature of our problems permits the use of two classical approaches. These semi-linear partial differential equations are split into a linear equation which contains the highly stiff part of the problem, and a nonlinear part that is expected to be varying slowly than the linear part. For the spatial discretization, we introduce higher-order symmetric finite difference scheme, and the resulting ordinary differential equations are then solved with the use of the family of implicit–explicit (IMEX) schemes. Stability properties of these schemes as well as the linear stability analysis of the problems are well presented. Numerical examples and results are also given to illustrate the accuracy and implementation of the methods.

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