Search results for "ESOL"
showing 10 items of 2444 documents
Benthic foraminifera distribution and stable isotope record of ODP Hole 160-963A
2011
New centennial-scale data of benthic foraminifera assemblages and of stable isotopes of foraminifera shells from the Sicily Channel, representative of surface and bottom waters, over the interval between about 140 and 110 kyr BP, are presented. During this period anoxia developed on the eastern Mediterranean basin and sapropel S5 deposited. Although anoxic sediments have not been deposited in the Sicily Channel, this area is strategic to study the character of intermediate waters, whose chemical-physical properties strongly precondition the eastern Mediterranean deep water formation. So far, no data from these water masses have been obtained, apart from the isotopic composition of shells of…
Chemistry of Globigerinoides ruber shells from ODP Site 160-963
2013
Here we present a high-resolution faunal, floral and geochemical (stable isotopes and trace elements) record from the sediments of Ocean Drilling Program Site 963 (central Mediterranean basin), which shows centennial/millennial-scale resemblance to the high-northern latitude rapid temperature fluctuations documented in the Greenland ice cores between 20 and 70 kyr BP. Oxygen and carbon isotopes, planktic foraminifera and calcareous nannofossil distributions suggest that Dansgaard-Oeschger (D/O) and Heinrich events (HE) are distinctly expressed in the Mediterranean climate record. Moreover, recurrent though subdued oscillations not previously identified in the Lateglacial Mediterranean sedim…
(Table 1) Trace element/Ca ratios of Orbulina universa shells from late Neogene Mediterranean samples
2008
A Mediterranean composite sedimentary record was analyzed for Ba/Ca ratios on carbonate shells of Orbulina universa planktonic foraminifer (Ba/Ca)carb providing the opportunity to study and assess the extent of freshwater inputs on the basin and possible impacts on its dynamics during the Tortonian to Recent period. A number of scanning electron microscope analyses and auxiliary trace element measurements (Mn, Sr, and Mg), obtained from the same samples, exclude important diagenetic effects on the studied biogenic carbonates and corroborate the reliability of (Ba/Ca)carb ratios in foraminifera calcite as indicators of seawater source components during the studied interval. A long-term trend…
Coccolithophora and geochemistry of sapropel S1 in ODP Hole 160-964B
2011
The cyclic development of anoxic conditions in the eastern Mediterranean deep sea waters is one of the most fascinating research topics in paleoceanographic studies. In combination with bottom water stagnation, enhanced primary production is a common explanation for the deposition of organic-rich layers (sapropels). This is supported by extensive evidence from both geochemical and micropaleontological studies. The correspondence of recent sapropel layers with peaks of the lower photic zone coccolithophore species Florisphaera profunda has been interpreted as a proxy for the development of a deep chlorophyll maximum (DCM), due to the pycnocline/nutricline shallowing into the lower part of th…
Stable isotopic composition of three foraminifera species in ODP Hole 160-963D
2020
Carbon-rich layers exist at both sides of the Mediterranean Sea sedimentary record and are called sapropels and organic rich layers (ORLs), respectively in the eastern and western basins. They have different levels of organic carbon accumulation and seafloor oxygen deprivation. The most recent sapropel and ORL deposition have a different timing, 10.8-6.1 and 14.5-9.0 ka respectively. Here we investigate oxygen isotopic records of three foraminifera species that occupy different habitats within the Sicily Channel water column since ~ 12.0 ka, thus in the sill between the eastern and western Mediterranean basins. These data are ice volume-corrected, to get information on water masses density …
A local level set method for liver segmentation in functional MR imaging
2011
Functional Magnetic Resonance (fMR) is a medical image technique in which a contrast is injected in the vascular system so that blood diffusion along it can be observed as variations of the signal intensity. The uptake variations of the contrast agent are used in early detection of tumorous tissue. For the diagnostic to be accurate, successive volumes must be correctly registered. For binary registration prior segmentation of the 3D fMR data is required. Here we present a local 3D level-set segmentation method which preserves details and edges, along with its multi-scale version which has the advantage of a great acceleration with respect to the single-scale version. Results of liver segmen…
Maximum Likelihood Estimation and non-linear least squares fitting with Levenberg-Marquardt Algorithm implementation in FPGA devices for high resolut…
2012
This work compares two possible solutions to achieve a higher resolution in a hodoscope based on Plastic Scintillating Fibers (PSF) by obtaining the point of maximum incidence of the radioactive beam. The two fitting algorithms proposed have been tested and implemented in Field Programmable Gate Array (FPGA) devices. On one hand, a probabilistic model based on the Maximum Likelihood Estimation (MLE) and on the other hand, non-linear least-squares fit with the Levenberg-Marquardt Algorithm (LMA).
El análisis de manuales y la identificación de problemas de investigación en Didáctica de las Matemáticas
2009
La ambigüedad del signo radical es un problema con raíces históricas que ha quedado recogido en una tradición de enseñanza reflejada en los manuales escolares. Aunque desde las matemáticas el problema no existe, no se puede decir lo mismo desde la didáctica. Por el contrario, el signo radical presenta sutilezas conceptuales y operatorias cuya omisión en los manuales es a menudo causa de malentendidos y conflictos fuertemente arraigados. Algunos de esos malentendidos son un producto de la enseñanza tradicional reflejada en los manuales que ignora los desarrollos matemáticos actuales.
6‐1: Invited Paper: Measuring Health Parameters with Large‐Area Organic Photodetector Arrays
2021
Solution-processed organic photodetectors (OPDs) have witnessed great progress in the past few years. With silicon-like performance achieved, OPDs enable new medical imaging applications by offering cost-effective light detection over large area. Herein, we illustrate the compelling advantages of high spatial and temporal resolution OPD arrays for medical X-ray detectors and wearable pulse oximeters.
Towards the Operational Spatialization of the Single Band Thermal Atmospheric Correction. Application to Landsat 7 ETM+
2018
This work aims to improve the accuracy in Land Surface Temperature (LST) from single-channel thermal sensors by providing spatialized maps of transmittance, upwelling and downwelling atmospheric radiances required in the radiative transfer equation. Two different techniques are introduced for the estimation of pixel-by-pixel atmospheric parameters, focusing on the correction of Landsat Thermal Infrared (TIR) data. First technique is based on the linearization of the atmospheric parameters with the total column water vapor (W), extracted from the MOD05 product, whereas a second technique uses the Single Band Atmospheric Correction (SBAC) tool. Ground-measured values of LST in an agricultural…