Sex chromosomes in plants have been known for a century, but only recently have we begun to understand the mechanisms behind sex determination in dioecious plants. Here, we discuss evolution of sex determination, focusing on Silene latifolia, where evolution of separate sexes is consistent with the classic “two mutations” model—a loss of function male sterility mutation and a gain of function gynoecium suppression mutation, which turned an ancestral hermaphroditic population into separate males and females. Interestingly, the gynoecium suppression function in (...) S. latifolia evolved via loss of function in at least two sex‐linked genes and works via gene dosage balance between sex‐linked, and autosomal genes. This system resembles X/A‐ratio‐based sex determination systems in Drosophila and Rumex, and could represent a steppingstone in the evolution of X/A‐ratio‐based sex determination from an active Y system. (shrink)

Este ensayo está dedicado a la serie grey paintings del artista norteamericano Cy Twombly. A partir de un análisis de Panorama y Cold Stream, planteo que la serie se vincula a formas de inscripción asociadas, simultáneamente, a lo verbal y lo pictórico. Si bien no es posible identificar letras ni palabras, estas obras manifiestan un estrecho vínculo con una dimensión gestual y corporal de la escritura. En mi análisis establezco relaciones con inscripciones arcaicas, con la criptografía, y con procesos de (...) alfabetización escolar. (shrink)

Aunque a primera vista lo cómico y lo sagrado parecen categorías excluyentes y, por qué no, opuestas, a lo largo de la historia encontramos ejemplos en los que tales manifestaciones humanas se entrelazan de manera directa y contundente. En este artículo analizaremos la relación entre estas dos categorías a la luz del uso del sarcasmo, la ironía y la hilaridad presentes en la obra de Issa Kobayashi, uno de los grandes exponentes del haikai zen. Comenzaremos con una delimitación de (...) los rasgos esenciales de lo cómico. Luego nos concentraremos en la convivencia del humor y la tradición religiosa del zen, y finalmente rastrearemos la comicidad sagrada en la obra del poeta japonés. (shrink)

西田幾多郎の中心概念「永遠の今」を外部の多様な言説に向けて開放することで、西田哲学の新たな可能性を切り開く。プラトン、アウグスティヌス、ハイデッガー、九鬼周造、デリダ、アガンベン、木村敏といった西洋哲 学、宗教学、現代思想、精神病理学の代表者たちの議論と西田の言説を突き合わせ、その緻密な解釈と検証を通して、これまで時間論で見逃されてきたカイロスの系譜とその意義を照らし出す。既成の西田研究に問題を投げ かける著者十年の集大成。岩波現代文庫オリジナル版。.

Genetic Algorithms(GAs) are effective approximation algorithms which focus on “hopeful area” in the searching process. However, in harder problems, it is often very difficult to maintain a favorable trade-off between exploitation and exploration. All individuals leave the big-valley including the global optimum, and concentrate on another big-valley including a local optimum often. In this paper, we define such a situation on conventional GAs as the “UV-phenomenon”, and suggest UV-structures as hard landscape structures that will cause the UV-phenomenon. We introduce a (...) test function which has explicit UV-structures, and show UV-phenomenon caused by them. Next we analyze Fletcher and Powell function to confirm our hypothesis. Finally we propose a novel framework of GAs which can cope with UV-structures. (shrink)

本研究は、史料的裏付けにもとづく、東アジア三地域における気の思想・文化の歴史や内容、特徴を明らかにし、東アジアにおける気の総合的・体系的研究の基礎を構築している。.

Graphical AbstractYeast mitochondria frequently mutate, and some dysfunctional mitochondria out-compete wild-type versions. The retrograde response enables yeast to tolerate dysfunction, but also produces ribosomal DNA circles (ERCs). We propose that ERC accumulation increases expression of the rDNA antisense gene, TAR1, which counteracts spread of respiration-deficient mitochondria in matings with wild-type yeast.

Something should be done for a better global environment as soon as possible. This paper investigates the direction of management of the global environment and proposes new, concrete ideas for it.

Kei Yoshida’s recent book Philosophy of the Social Sciences: An Introduction is the first introductory textbook on the philosophy of the social sciences written in Japanese. It concisely expounds on a wide range of topics in the discipline, while its explication of those topics is not impartial or neutral as the author himself says. This paper gives a critical review of the book. The first half of it briefly overviews and assesses the book as a whole. The latter half of (...) the paper reconstructs the gist of the author’s exposition of the naturalism/interpretivism debate and criticizes it. (shrink)

This paper presents a kernel density estimation method by means of real-coded crossovers. Functions of real-coded crossover operators are composed of probabilistic density estimation from parental populations and sampling from estimated models. Real-coded Genetic Algorithm (RCGA) does not explicitly estimate probabilistic distributions, however, probabilistic model estimation is implicitly included in algorithms of real-coded crossovers. Based on this understanding, we exploit the implicit estimation of probabilistic distribution of crossovers as a kernel density estimator. We also propose an application of crossover kernels (...) to Expectation-Maximization estimation (EM) of Gaussian mixtures. (shrink)