Continua that are approximative absolute neighborhood retracts (AANR’s) are characterized as absolute terminal retracts, i.e., retracts of continua in which they are embedded as terminal subcontinua. This implies that any AANR continuum has a dense arc component, and that any ANR continuum is an absolute terminal retract. It is proved that each absolute retract for any of the classes of: tree-like continua, $\lambda $-dendroids, dendroids, arc-like continua and arc-like $\lambda $-dendroids is an approximative absolute retract (so it is an AANR). Consequently, all these continua have the fixed point property, which is a new result for absolute retracts for tree-like continua. Related questions are asked.
Torsion-free covers are considered for objects in the category $q_2.$ Objects in the category $q_2$ are just maps in $R$-Mod. For $R = {\mathbb Z},$ we find necessary and sufficient conditions for the coGalois group $G(A \longrightarrow B),$ associated to a torsion-free cover, to be trivial for an object $A \longrightarrow B$ in $q_2.$ Our results generalize those of E. Enochs and J. Rado for abelian groups.
This paper aims to provide a comprehensive survey of phrasal and clausal comparative constructions in the N. W. Caucasian language Abkhaz (in relation to data from the standard, Abzhywa dialect). Following the lead of Knecht (1976), the following three terms will be used throughout this article: (a) Remainder = in the phrasal comparative, a single NP (preceded by “than” in English); in the clausal comparative, the remains of the clause; (b) Trigger = the quantified constituent in the controlling clause; (c) Target = the compared constituent in the comparative clause obligatorily deleted by Comparative Deletion.
In der vorliegenden Arbeit werden die allgemeinen Beziehungen abgeleitet, durch die die Abnahme der Sonnenflecken vom Mittelpunkt zum Rand der Sonnenscheibe mit Rücksicht auf die Verteilung der Sonnenflecken in heliographischen Breiten bestimmt wird, wobei drei verschiedene Methoden der Darstellung dieser Abnahme verwendet werden. Durch eine annähernde Berechnung wird gezeigt, dass alle drei Methoden praktische einen übereinstimmenden Verlauf der Abnahme ergeben, und dass die verschiedene Sonnenfleckenzahl in verschiedenen heliographischen Breiten praktisch keinen Enfluss auf den Verlauf der Abnahme der Sonnenflecken gegen den Sonnenrand ausübt. Die von Fr. Reggenhausen bestimmte Abnahme der Sonnenflecken gegen den Sonnenrand unterscheidet sich aus unbekannten Gründen wesentlich von den übrigen Bestimmungen und von unseren eigenen Resultaten.
The abundance of the objects with splitted nuclei among the candidates - the members of tight systems can be explained by the existence of bright HII regions in their central parts and also by the existence of dust lanes in their nuclear regions. 270 objects out of our lists are listed in IRAS catalogue.