Search results for "CLOSURE"
showing 10 items of 411 documents
p −1-Linear Maps in Algebra and Geometry
2012
At least since Habousch’s proof of Kempf’s vanishing theorem, Frobenius splitting techniques have played a crucial role in geometric representation theory and algebraic geometry over a field of positive characteristic. In this article we survey some recent developments which grew out of the confluence of Frobenius splitting techniques and tight closure theory and which provide a framework for higher dimension geometry in positive characteristic. We focus on local properties, i.e. singularities, test ideals, and local cohomology on the one hand and global geometric applicatioms to vanishing theorems and lifting of sections on the other.
Social Lives of Monumental Walls: Hunting along the Upper Tigris
2021
On the left bank of the Tigris in northern Iraq, in an area today partially flooded by the Mosul Dam reservoir, lies an enigmatic monumental enclosure known in the literature as the “Tigris Wall.” Before its partial submersion under the waters of the modern lake, the large L-shaped embankment, about 4 × 4 km long, enclosed an area of ca. 1600 ha, overlooking the Tigris and its alluvial plain. By means of a holistic strategy that includes different levels of analysis (remote sensing, pedestrian and UAV photogrammetric surveys, excavation, and settlement pattern analysis), this paper addresses the structure, its context, and its environment. Relying on the results of this multi-disciplinary a…
Spatial variability of soft-bottom macrobenthic communities in northern Sicily (Western Mediterranean): Contrasting trawled vs. untrawled areas
2016
13 páginas, 9 tablas, 5 figuras
Evaluating structural and compositional canopy characteristics to predict the light-demand signature of the forest understorey in mixed, semi-natural…
2020
Questions: Light availability at the forest floor affects many forest ecosystem processes, and is often quantified indirectly through easy-to-measure stand characteristics. We investigated how three such characteristics, basal area, canopy cover and canopy closure, were related to each other in structurally complex mixed forests. We also asked how well they can predict the light-demand signature of the forest understorey (estimated as the mean Ellenberg indicator value for light [“EIVLIGHT”] and the proportion of “forest specialists” [“%FS”] within the plots). Furthermore, we asked whether accounting for the shade-casting ability of individual canopy species could improve predictions of EIV…
Species loss leads to community closure
2008
Global extinction of a species is sadly irreversible. At a local scale, however, extinctions may be followed by re-invasion. We here show that this is not necessarily the case and that an ecological community may close its doors for re-invasion of species lost from it. Previous studies of how communities are assembled have shown that there may be rules for that process and that limitations are set to the order by which species are introduced and put together. Instead of focusing on the assembly process we randomly generated simple competitive model communities that were stable and allowed for two to 10 coexisting species. When a randomly selected single species was removed from the communit…
Kinematics and U-Pb zircon ages of the sole metamorphics of the Marmaris Ophiolite, Lycian Nappes, Southwest Turkey
2018
In the eastern Mediterranean, the Lycian Nappes are found in the structurally uppermost position in the Anatolide-Tauride belt related to the closure of the Neotethys. In Western Turkey, the Marmaris Ophiolite with the metamorphic sole occupies the uppermost tectonic position in the Lycian belt. The metamorphic sole is represented by discontinuous tectonic slices composed of amphibolites, phyllites, micashists and quartzo-feldspathic micaschists. Zircons from the micashists and quartzo-feldspathic micaschists display dark cores and rims. The cores yield ages between 229 and 175 Ma, inner rims yield ages between 153 and 143 Ma and the outer rims show a concordia age of 96.7 ± 0.79 Ma. In ter…
Return and Disclosure of Research Results: Parental Attitudes and Needs Over Time in Pediatric Oncology.
2017
Objectives To explore parental attitudes regarding the return and disclosure of research findings in pediatric cancer trials over time. Study design Two surveys were set up to evaluate the stability of parental attitudes. One survey was carried out among 581 parents whose child was diagnosed recently (response rate, 53.5%). A second, population-based survey was set up with a time interval of 4 years between first cancer diagnosis and survey in which 1465 parents were included (response rate, 55.1%). Results Almost all surveyed parents stated a parental right to receive aggregate research results. Fifty-five percent of the parents who recently participated in trials and 62% of those asked af…
A TRAPPC6B splicing variant associates to restless legs syndrome
2016
Abstract INTRODUCTION: RLS is a common movement disorders with a strong genetic component in its pathophysiology, but, up to now, no causative mutation has been reported. METHODS: We re-evaluated the previously described RLS2 family by exome sequencing. RESULTS: We identified fifteen variations in the 14q critical region. The c.485G > A transition of the TRAPPC6B gene segregates with the RLS2 haplotype, is absent in 200 local controls and is extremely rare in 12988 exomes from the Exome Variant Server (EVS). This variant alters a splicing site and hampers the normal transcript processing by promoting exon 3-skipping as demonstrated by minigene transfection and by patient transcripts. CON…
Evolutionary conserved role of eukaryotic translation factor eIF5A in the regulation of actin-nucleating formins
2017
AbstractElongation factor eIF5A is required for the translation of consecutive prolines, and was shown in yeast to translate polyproline-containing Bni1, an actin-nucleating formin required for polarized growth during mating. Here we show that Drosophila eIF5A can functionally replace yeast eIF5A and is required for actin-rich cable assembly during embryonic dorsal closure (DC). Furthermore, Diaphanous, the formin involved in actin dynamics during DC, is regulated by and mediates eIF5A effects. Finally, eIF5A controls cell migration and regulates Diaphanous levels also in mammalian cells. Our results uncover an evolutionary conserved role of eIF5A regulating cytoskeleton-dependent processes…
Cbt modulates Foxo activation by positively regulating insulin signaling in Drosophila embryos.
2018
In late Drosophila embryos, the epidermis exhibits a dorsal hole as a consequence of germ band retraction. It is sealed during dorsal closure (DC), a morphogenetic process in which the two lateral epidermal layers converge towards the dorsal midline and fuse. We previously demonstrated the involvement of the Cbt transcription factor in Drosophila DC. However its molecular role in the process remained obscure. In this study, we used genomic approaches to identify genes regulated by Cbt as well as its direct targets during late embryogenesis. Our results reveal a complex transcriptional circuit downstream of Cbt and evidence that it is functionally related with the Insulin/insulin-like growth…