26,967 research outputs found
t-structures for relative D-modules and t-exactness of the de Rham functor
This paper is a contribution to the study of relative holonomic D-modules. Contrary to the absolute case, the standard t-structure on holonomic D-modules is not preserved by duality and hence the solution functor is no longer t-exact with respect to the canonical, resp. middle-perverse, t-structure.
We provide an explicit description of these dual t-structures. We use this description to prove that the solution functor as well as the relative Riemann-Hilbert functor are t-exact with respect to the dual t-structure and to the middle-perverse one while the de Rham functor is t-exact for the canonical, resp. middle-perverse, t-structure and their duals
Effects of a large irrigation reservoir on aquatic and riparian plants: a history of survival and loss
Dammed rivers have unnatural stream flows, disrupted sediment dynamics, and rearranged
geomorphologic settings. Consequently, fluvial biota experiences disturbed functioning in the novel
ecosystems. The case study is the large irrigation reservoir Alqueva in Guadiana River, Southern Iberia.
The study area was divided into three zones: upstream and downstream of the dam and reservoir.
For each zone, species composition and land use and land cover (LULC) were compared before
and after the Alqueva Dam implementation. Data consist of aquatic and riparian flora composition
obtained from 46 surveys and the area (%) of 12 classes of LULC obtained in 90 riverine sampling
units through the analysis of historical and contemporary imagery. There was an overall decrease
of several endemic species and on the riparian shrublands and aquatic stands, although di erences
in the proportion of functional groups were not significant. Nevertheless, compositional diversity
shows a significant decline in the upstream zone while landscape diversity shows an accentuated
reduction in the reservoir area and downstream of the dam, which is likely related to the loss of
the rocky habitats of the âoldâ Guadiana River and the homogenization of the riverscape due to the
irrigation intensification. The mitigation of these critical changes should be site-specific and should
rely on the knowledge of the interactions between surrounding lands, ecological, biogeomorphologic,
and hydrological components of the fluvial ecosystemsinfo:eu-repo/semantics/publishedVersio
O profetismo no Tratado de Iosepho de FĂlon de Alexandria
Tendo em conta as vĂĄrias conotaçÔes dadas aos chamados profetas bĂblicos, Ă© feita uma anĂĄlise da personagem e feitos de JosĂ©, filho do patriarca Jacob, segundo a narrativa de FĂlon de Alexandria no tratado De Josepho.FCT atĂ© Setembro 201
ΊÏÏÎčÏ no Tratado de FĂlon de Alexandria De Iosepho
Analisam-se as diversas acepçÔes do lema grego fĂșsis, com proposta de lexicografia para o vocĂĄbulo e introdução de uma nova acepção, Ă luz da sua utilização por FĂlon de AlexandriaFCT atĂ© Setembro 201
Critical dialogues: slow readings of English literary texts
The reader will find gathered together in this volume a selection of articles and essays that have been separately published over the past three decades as a result of my teaching practice and research activity. In chronological terms, they span a period from 1985 until May 2008. These texts were chosen because they are considered to be representative of the type of work I usually do in my classes, undoubtedly as a result of my own academic background, based on a deliberate and specific form of approach to literary texts, my own choice of English authors and, lastly, my most recent interest in inter-art studies.Fundação para a CiĂȘncia e a Tecnologi
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