In this paper we propose an indexing structure for bitemporal databases. Such structure is based on two trees, one indexing valid time and another indexing transaction time. The trees share pointers to the actual data records, which are thus not duplicated. Bitemporal queries are processed by dividing the query in two parts, a valid time part and a transaction time part. Each tree is searched a...

There is a vibrant (but minority) community among philosophical logicians seeking to resolve the paradoxes of classes, properties and truth by way of adopting some non-classical logic in which trivialising paradoxical arguments are not valid. There is also a long tradition in theoretical computer science—going back to Dana Scott’s fixed point model construction for the untyped λ-calculus [35, 3...

As is made clear at the outset, he by no means wanted to deny the existence of discernible points of contact betwe(!n distinct religious 193 traditions; the study of parallels, in his view, is valid and should be encouraged. His criticisms were directed, rather, at what he saw to be misuses of this kind of comparative study. These misuses fall generally into two categories. The first of these c...

Free and membrane-bound polyribosomes were isolated from the forebrain of actively myelinating 24-day-old rats. The poly(A)+ RNA (polyadenylated RNA) extracted from both fractions was translated in vitro in reticulocyte lysates [Hall & Lim (1981) Biochem. J. 196. 327-336] in the presence or absence of a heterologous microsomal membrane fraction from dog pancreas. The rat myelin basic proteins s...

The main goal of this volume is to present a cultural-developmental approach to moral psychology. The volume addresses the divergent and multiple ways that morality develops in diverse cultures, thus synthesizing developmental and cultural perspectives. It draws attention to the question of how to bridge the lenses of developmental and cultural psychology. The authors expand current theoretical...

After the boom of pharmacological research during the 1950s, mainly as a result of the screening technique, the identification of active molecules, their reshaping by means of pharmaco-chemical drug design, and the creation of extremely efficacious and successful medicines, the pharmaceutical world sought a new source of inspiration. Such biota as the tropical forest, a quantity of plants credi...

This research sought to examine the mediating role of psychological capital in the relationship between authentic leadership and work engagement among school principals and teachers. The study had a descriptive, correlational design. The statistical population of the study was comprised of all school principals and teachers in Aleshtar (located in Lorestan Province) in school year 2016-17 from ...

today the most common formal communication tool in social systems is writing so that formalization as one of the main structural dimensions of organization is measured in terms of the written rules level. confidence-building of writing in administrative relationships is so that lawyers consider written documents as one of evidences in courts. as far as the validity of written documents exceeded...

this study sought to investigate the impact of teaching speech acts and role relations through authentic audio-taped and video-taped materials on the level of iranian efl learners’ pragmatic competence. to this end, 55 intermediate learners were ed and randomly assigned to two experimental groups: the audio-taped group and the video-taped group. during the treatment, the audio-taped group recei...

in recent years, there has been a great concern about strategic supply chain management. the supply chain configuration approach is related to strategic management of material and information flows. most of suggested configurations in the part of strategic direction are based on environmental factors and structure-conduct-performance approach. exploring supply chain configuration with emphasis ...