Search results for "tract"
showing 10 items of 9251 documents
Chemical aging of atmospheric mineral dust during transatlantic transport
2016
Abstract. Transatlantic dust transport has many implications for the atmosphere, ocean and climate. We present a modeling study on the impact of the key processes (dust emissions flux, convection and dust aging parameterizations) that control the transatlantic dust transport. Typically, the Inter-Tropical Convergence Zone (ITCZ) acts as a barrier for the meridional dust transport. To characterize the dust outflow over the Atlantic Ocean, we address two regional phenomena: (i) dust interactions with the ITCZ (DIZ) and (ii) the adjacent dust transport over the Atlantic Ocean (DTA). In the DTA zone, the dust loading shows a steep and linear gradient westward over the Atlantic Ocean where parti…
THEMIS: A Parameter Estimation Framework for the Event Horizon Telescope
2020
This is an open access article.-- Full list of authors: Broderick, Avery E.; Gold, Roman; Karami, Mansour; Preciado-López, Jorge A.; Tiede, Paul; Pu, Hung-Yi; Akiyama, Kazunori; Alberdi, Antxon; Alef, Walter; Asada, Keiichi; Azulay, Rebecca; Baczko, Anne-Kathrin; Baloković, Mislav; Barrett, John; Bintley, Dan; Blackburn, Lindy; Boland, Wilfred; Bouman, Katherine L.; Bower, Geoffrey C.; Bremer, Michael; Brinkerink, Christiaan D.; Brissenden, Roger; Britzen, Silke; Broguiere, Dominique; Bronzwaer, Thomas; Byun, Do-Young; Carlstrom, John E.; Chael, Andrew; Chatterjee, Shami; Chatterjee, Koushik; Chen, Ming-Tang; Chen, Yongjun; Cho, Ilje; Conway, John E.; Cordes, James M.; Crew, Geoffrey B.; Cu…
Spectral alignment of multi-temporal cross-sensor images with automated kernel canonical correlation analysis
2015
In this paper we present an approach to perform relative spectral alignment between optical cross-sensor acquisitions. The proposed method aims at projecting the images from two different and possibly disjoint input spaces into a common latent space, in which standard change detection algorithms can be applied. The system relies on the regularized kernel canonical correlation analysis transformation (kCCA), which can accommodate nonlinear dependencies between pixels by means of kernel functions. To learn the projections, the method employs a subset of samples belonging to the unchanged areas or to uninteresting radiometric differences. Since the availability of ground truth information to p…
Anthropogenic lead distribution in soils under arable land and permanent grassland estimated by Pb isotopic compositions
2008
International audience; The role of land use on fate of metals in soils is poorly understood. In this work, we studied the incorporation of lead in two neighboring soils with comparable pedogenesis but under long-term different agricultural management. Distributions of anthropogenic Pb were assessed from concentrations and isotopic compositions determined on bulk horizon samples, systematical 5–10 cm increment samples, and on 24-h EDTA extracts. Minor amounts of anthropogenic lead were detected until 1-m depth under permanent grassland, linked to high earthworm activity. In arable land, exogenous Pb predominantly accumulated at depths <60 cm. Although the proximity between the two sites ens…
Predicting year of plantation with hyperspectral and lidar data
2017
This paper introduces a methodology for predicting the year of plantation (YOP) from remote sensing data. The application has important implications in forestry management and inventorying. We exploit hyperspectral and LiDAR data in combination with state-of-the-art machine learning classifiers. In particular, we present a complete processing chain to extract spectral, textural and morphological features from both sensory data. Features are then combined and fed a Gaussian Process Classifier (GPC) trained to predict YOP in a forest area in North Carolina (US). The GPC algorithm provides accurate YOP estimates, reports spatially explicit maps and associated confidence maps, and provides sens…
Land set-up systems in Italy: A long tradition of soil and water conservation sewed up to a variety of pedo-climatic environments
2020
Land set-up systems in Italy were and, in a few cases, still are integral parts of agricultural landscapes. The soils of Italy mirror a wide variety of climates and morphologies and derive from a great diversity of parent materials influenced by different soil temperature and moisture regimes. Furthermore, their development was influenced by several anthropogenic activities over time including land settings. Land set-up systems have been widely used throughout the Italian soilscape to regulate surface and underground water and to improve the physical soil features in a way that ensures mixed herbaceous and tree-crops cultivation. In recent times, new technologies have been introduced in agr…
Linking theories, past practices, and archaeological remains of movement through ontological reasoning
2020
The amount of information available to archaeologists has grown dramatically during the last ten years. The rapid acquisition of observational data and creation of digital data has played a significant role in this &ldquo
L’étude archéologique des mortiers de chaux médiévaux : vers une meilleure compréhension des gestes du maçon
2020
International audience; Ces dernières décennies, l’étude des mortiers archéologiques, en particulier médiévaux, a connu un essor considérable en lien étroit avec celui de l’archéologie du bâti. Matériaux composites, possédant à la fois une forte identité géologique et un caractère anthropique certain, les mortiers sont considérés comme étant des marqueurs chronologiques potentiels pouvant aider à la compréhension de l’évolution d’un bâtiment. Mais, au-delà des problèmes de chronologie, l’étude du mortier de chaux, qui représente près de la moitié du volume d’une maçonnerie, a permis également de progresser sur la connaissance de toute la chaîne opératoire associée. Ainsi, du four à chaux au…
Developmental aspects of morphological disparity dynamics: a simple analytical exploration
2011
15 pages; International audience; We devised a simple model for assessing the role of development in shaping the evolution of morphological disparity. Disparity of a clade at any given time is expressed in terms of the developmental dynamics that lead to the variety of adult morphotypes observed. We use assumed phenotypic manifestations of developmental processes, as they could be detected from allometric characterizations, to distinguish a few, nonexclusive types of evolutionary changes in ontogeny. On the basis of this formalization, we describe the diversification of hypothetical clades, using the standard curve of adult morphological disparity, the curve of juvenile disparity, and the c…
Evaluation of the Ability of Polyphenol Extracts of Cocoa and Red Grape to Promote the Antioxidant Response in Yeast Using a Rapid Multiwell Assay
2017
Saccharomyces cerevisiae has been used as a model organism to study the capacity of cocoa and red grape extracts to trigger an antioxidant response. A methodology adapted to microtiter plates has been developed to monitor yeast growth after culture preincubation with food ingredients and exposure to oxidative stress by hydrogen peroxide and menadione. This methodology proved effective in measuring the ability of cocoa and red grape extracts to promote an antioxidant response in yeast, and also the prospect of conducting dose-response studies. Additionally, the method has proven useful to perform studies with mutant strains lacking genes that may be related to the mechanism of action underly…