1,848 research outputs found
Using ocean models to predict spatial and temporal variation in marine carbon isotopes
Natural-abundance stable isotope ratios provide a wealth of ecological information relating to food web structure, trophic level, and location. The correct interpretation of stable isotope data requires an understanding of spatial and temporal variation in the isotopic compositions at the base of the food web. In marine pelagic environments, accurate interpretation of stable isotope data is hampered by a lack of reliable, spatio-temporally distributed measurements of baseline isotopic compositions. In this study, we present a relatively simple, process-based carbon isotope model that predicts the spatio-temporal distributions of the carbon isotope composition of phytoplankton (here expressed as δ13CPLK) across the global ocean at one degree and monthly resolution. The model is driven by output from a coupled physics-biogeochemistry model, NEMO-MEDUSA, and operates offline; it could also be coupled to alternative underlying ocean model systems. Model validation is challenged by the same lack of spatio-temporally explicit data that motivates model development, but predictions from our model successfully reproduce major spatial patterns in carbon isotope values observed in zooplankton, and are consistent with simulations from alternative models. Model predictions represent an initial hypothesis of spatial and temporal variation in carbon isotopic baselines in ocean areas where a few data are currently available, and provide the best currently available tool to estimate spatial and temporal variation in baseline isotopic compositions at ocean basin to global scales
PIDR(s): IDR(s) as a Projection Method
The Induced Dimension Reduction(s) method (or the IDR(s) method) is an example of an iterative method used for solving systems of linear equations. Projection methods are a special type of iterative method. They find an approximate solution in a subspace (the right subspace) by requiring that the residual is orthogonal to another subspace (the left subspace). In this thesis we investigate how we can implement IDR(s) as a projection method. We call this method IDR(s), which stands for Projected IDR(s).We present an implementation of PIDR(s) for solving systems of linear equations and for solving eigenvalue problems. These implementations are not meant to be optimal, but they are used to show that IDR(s) can indeed be seen as a projection method.Track: educationScience Education and CommunicationApplied Science
Actie podium van de stad - De plek voor overlapping van publieke en private actie; onderzoeksrapport. Het grote huis en de kleine stad - de stad van ankers in plaats van wortels; essay, onderdeel van onderzoeksrapport.
Het onderzoeksrapport is in samenwerking van bovengenoemde auteurs tot stand gekomen. Het essay is enkel geschreven door M.B. Dekker.At home in the city - BerlinDwellingArchitectur
Author Correction:A 41,500 year-old decorated ivory pendant from Stajnia Cave (Poland)
Correction to: Scientific Reports https://doi.org/10.1038/s41598-021-01221-6, published online 25 November 2021The original version of this Article contained errors in the author list where Marjolein D. Bosch was omitted from the author list, and Mikołaj Urbanowski was incorrectly listed as an author of the original Article, and has subsequently been removed.The Author contributions section now reads:“S.T. W.N. and A.N. conceived the project; S.T., W.N., A.P., M.B., S.C., M.D., H.F., A.M., M.D. B., D.P., M.P.R., C.M.R., V.S-M., G.M.S., P.S., M.S., K.S., A.V., F.W., H.W., A.W., M.Z., S.B., A.N., J-J. H., performed research; S.T., A.P., W.N., M.B., M.D.B., S.C., M.D., H.F., A.M., D.P., M.P.R., C.M.R., V.S-M., G.M.S., P.S., M.S., K.S., A.V., F.W., H.W., A.W., M.Z., S.B., A.N., J-J. H. analysed all archaeological data; S.T. and A.P. wrote the paper with the collaboration of all the co-authors.”The original Article and its accompanying Supplementary Information file have been corrected
Internet and e-health Care: an Interdigital Field of Study
The foreword focuses on a historical definition of the e-health field. The author contributed to shaping the e-health field in the international community being one of the pioneers' scholars since the 1990s. The chapter discusses current and challenging future scenarios based on the international evolution that brings about new challenges
LA PRIMA RICEZIONE DELLA FENOMENOLOGIA NEGLI STATI UNITI: UN'ANALISI STORICO-CRITICA
My research analyzes the characteristics of the first reception of husserlian phenomenology in the United States. The base of this work is a detailed historiographical reconstruction of this phase representing the point of departure of all those studies on phenomenological tradition that have been developed in the American academic world. Several institutions belong to the context in which this reception took place: the New School for Social Research as the original center for the teaching of phenomenology and a number of societies arisen since the sixties to diffuse Husserl’s philosophy in the United States (First Part: Chapter 2 and Chapter 3).
This first reception, promoted since the late thirties by Kaufmann, Schutz, Gurwitsch, Cairns and Farber, must be distinguished from an earlier phase, presenting only the general approach to Husserl’s thought of some American scholars (Second Part: Chapter 1). The origin of the studies of each author undoubtedly typifies their promotion of husserlian phenomenology: Gurwitsch, Schutz and Kaufmann belong to the European tradition, (First Part: Chapter 1) while the Americans Farber and Cairns mainly owe the growing interest in Husserl’s thought to their studies in Freiburg (Second Part: Chapter 2). Nevertheless, during this phase of reception of phenomenology, the original adherence to his lesson – useful to distinguish them from others Husserl’s students emigrated in United States – gradually disappears from their critiques. The aim of my research is to single out the salient features that characterize the different interpretations of Husserl’s thought elaborated by each author, whereas their originality can be indicated as decisive for following developments (Third Part). Gurwitsch builds an interesting critique of Husserl’s whole-part theory, focuses his analysis on the noema, and elaborates a non-egological conception of consciousness. Schutz’s critique of transcendental phenomenology mainly refers to his concept of mundane intersubjectivity. For what concerns Cairns, his few writings published until now don’t allow to deepen the exam on his interpretation. After the arrival in the United States, Kaufmann concentrates his discussion on the relationship between husserlian phenomenology and the logic. Farber proposes a critique which is far from being an original interpretation, although his analysis remains bound to the interest in phenomenology until the end.
With this work I want to explain how the interest about husserlian phenomenology began in the United States, who were its promoters, and also what kind of interpretations they developed in the American academic world. It must be considered that they hadn’t a decisive influence on further developments of phenomenological studies, but in any case helped bringing the attention on Husserl’s thought throughout their teaching
Geographic distribution of feather δ34S in Europe
Geographic distribution models of environmentally stable isotopes (the so-called “isoscapes”) are widely employed in animal ecology, and wildlife forensics and conservation. However, the application of isoscapes is limited to elements and regions for which the spatial patterns have been estimated. Here, we focused on the ubiquitous yet less commonly used stable sulfur isotopes (δ34S). To predict the European δ34S isoscape, we used 242 feather samples from Eurasian Reed Warbler (Acrocephalus scirpaceus) formed at 69 European wetland sites. We quantified the relationships between sample δ34S and environmental covariates using a random forest regression model and applied the model to predict the geographic distribution of δ34S. We also quantified within-site variation in δ34S and complementarity with other isotopes on both individual and isoscape levels. The predicted feather δ34S isoscape shows only slight differences between the central and southern parts of Europe while the coastal regions were most enriched in 34S. The most important covariates of δ34S were distance to coastline, surface elevation, and atmospheric concentrations of SO2 gases. The absence of a systematic spatial pattern impedes the application of the δ34S isoscape, but high complementarity with other isoscapes advocates the combination of multiple isoscapes to increase the precision of animal tracing. Feather δ34S compositions showed considerable within-site variation with highest values in inland parts of Europe, likely attributed to wetland anaerobic conditions and redox sensitivity of sulfur. The complex European geography and topography as well as using δ34S samples from wetlands may contribute to the absence of a systematic spatial gradient of δ34S values in Europe. We thus encourage future studies to focus on the geographic distribution of δ34S using tissues from diverse taxa collected in various habitats over large land masses in the world (i.e., Africa, South America, or East Asia
Response of mountain plovers to plague-driven dynamics of black-tailed prairie dog colonies
Sylvatic plague is a major factor influencing the dynamics of black-tailed prairie dog (Cynomys ludovicianus) colonies in the western Great Plains. We studied the nesting response of the mountain plover (Charadrius montanus), a grassland bird that nests on prairie dog colonies, to plague-driven dynamics of prairie dog colonies at three sites in the western Great Plains. First, we examined plover nest distribution on colonies that were previously affected by plague, but that had been recovering (expanding) for at least 6 years. Plovers consistently nested in both young (colonized in the past 1–2 years) and old (colonized for 6 or more years) portions of prairie dog colonies in proportion to their availability. Second, we examined changes in plover nest frequency at two sites following plague epizootics, and found that mountain plover nest numbers declined relatively rapidly (≤2 years) on plague-affected colonies. Taken together, our findings indicate that available plover nesting habitat associated with prairie dog colonies closely tracks the area actively occupied by prairie dogs each year. Given the presence of plague throughout most of the mountain plover’s breeding range in the western Great Plains, important factors affecting plover populations likely include landscape features that determine the scale of plague outbreaks, the distance that plovers move in response to changing breeding habitat conditions, and the availability and quality of alternate breeding habitat within the landscape.This article is published as Augustine, D.J., Dinsmore, S.J., Wunder, M.B. et al. Response of mountain plovers to plague-driven dynamics of black-tailed prairie dog colonies. Landscape Ecol 23, 689 (2008). doi:10.1007/s10980-008-9230-y.
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Modelling the Social Environment: Towards Socially Adaptive Electronic Partners
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Interactive Intelligenc
What should I do?: Deriving norms from actions,values and context
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Interactive Intelligenc
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