Search results for " database"
showing 10 items of 684 documents
Study of the coordination of ortho-tyrosine and trans-4-hydroxyproline with aluminum(III) and iron(III)
2018
Abstract The coordination of amino acids ortho-tyrosine (o-Tyr, 1) and trans-4-hydroxyproline (HPro, 2) with the biologically important trivalent metal ions Al(III) and Fe(III) in aqueous solution was investigated by 1H and 13C high resolution NMR, Laser Desorption Mass Spectrometry (LD-MS), and MS/MS experiments. Potentiometric measurements were also carried out in 0.16 M NaCl, 37 °C, by varying the pH between 2.0 and 3.5. NMR spectra recorded on aqueous solutions of amino acids 1 or 2 in the presence of the appropriate trivalent metal chloride suggested that binding of Al(III) and Fe(III) involved the COOH and NH2 functional groups of ligands, while their phenolic and alcoholic groups whi…
Near-infrared radiative transfer modelling with different CH4 spectroscopic databases to retrieve atmospheric methane total amount
2011
International audience; Atmospheric methane content can be retrieved from measurements of solar radiation attenuated by the atmosphere in the near infrared spectral region where the space-borne and ground-based spectrometers carry out regular measurements. It is shown, in the present work, that the different spectroscopic databases can give significantly different results for both forward simulations of the atmospheric transmittance and the inverse problem solution to retrieve the CH4 total content in the atmosphere using spectra measured by ground-based FTIR spectrometer in the near infrared spectral region. These discrepancies and the problem of the reduction of their influence on the atm…
Methane line parameters in the HITRAN2012 database
2013
International audience; The compilation of methane molecular line parameters was updated to include new global analyses and measurements for 12CH4, 13CH4 and 12CH3D. Over 70% of the methane parameters in HITRAN2008 were replaced; existing parameters retained were the microwave lines and the Dyad of 13CH4 near 7 μm and ν6 of 13CH3D near 8.7 μm, 12CH3D (7-4076 cm-1), hot bands of 12CH4 (1887-3370 cm-1) and normal sample CH4 (4800-5550 cm-1 and 8000-9200 cm-1). With a minimum intensity at 296 K in units of cm-1/(molecule cm-2) set to 10-37 for the far-IR and 10-29 for the mid- and near-IR, the methane database increased from 290,091 lines in HITRAN2008 to 468,013 lines, and three-fourths of th…
Using the methods of radiospectroscopy (EPR, NMR) to study the nature of the defect structure of solid solutions based on lead zirconate titanate (PZ…
2014
The nature of intrinsic and impurity point defects in lead zirconate titanate (PZT) ceramics has been explored. Using electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS) methods, several impurity sites have been identified in the materials, including the Fe 3+ -oxygen vacancy (VO) complex and Pb ions. Both of these centers are incorporated into the PZT lattice. The Fe 3+ -V paramagnetic complex serves as a sensitive probe of the local crystal field in the ceramic; the symmetry of this defect roughly correlates with PZT phase diagram as the composition is varied from PbTiO 3 to PbZrO 3 . NMR spectra 207 Pb in PbTiO 3 , PbZrO 3 ,…
On the blue phase structure of hydrogen-bonded liquid crystals via 19F NMR
2018
Abstract 19 F NMR spectra are simulated for blue phase I of FPHG( St 1.5 ∗ Ap 1.5 ) based on a model of a double-twisted substructure inside cylinders that form a body-centred cubic lattice. A kinetic matrix is included to describe jump processes over quarter pitch lengths. Though the lines in the NMR spectra are broad and featureless, changes in the widths and positions with temperature are well described by the blue phase model structure. The spectra in the chiral nematic N∗ phase are also simulated. Dynamics in the BP I are found to be slower than in the N∗ phase.
Interface thermodynamic model for low pressure evaporation
1979
New insights into the gut microbiome in loggerhead sea turtles Caretta caretta stranded on the Mediterranean coast
2019
Caretta caretta is the most common sea turtle species in the Mediterranean Sea. The species is threatened by anthropomorphic activity that causes thousands of deaths and hundreds of strandings along the Mediterranean coast. Stranded turtles are often cared for in rehabilitation centres until they recover or die. The objective of this study was to characterize the gut microbiome of nine sea turtles stranded along the Sicilian coast of the Mediterranean Sea using high-throughput sequencing analysis targeting V3–V4 regions of the bacterial 16S rRNA gene. Stool samples were collected from eight specimens hosted in the recovery centre after a few days of hospitalization (under 7) and from one ho…
Change Discovery in Heterogeneous Data Sources of a Data Warehouse
2020
Data warehouses have been used to analyze data stored in relational databases for several decades. However, over time, data that are employed in the decision-making process have become so enormous and heterogeneous that traditional data warehousing solutions have become unusable. Therefore, new big data technologies have emerged to deal with large volumes of data. The problem of structural evolution of integrated heterogeneous data sources has become extremely topical due to dynamic and diverse nature of big data. In this paper, we propose an approach to change discovery in data sources of a data warehouse utilized to analyze big data. Our solution incorporates an architecture that allows t…
A Tutorial on Computational Cluster Analysis with Applications to Pattern Discovery in Microarray Data
2008
Background Inferring cluster structure in microarray datasets is a fundamental task for the so-called -omic sciences. It is also a fundamental question in Statistics, Data Analysis and Classification, in particular with regard to the prediction of the number of clusters in a dataset, usually established via internal validation measures. Despite the wealth of internal measures available in the literature, new ones have been recently proposed, some of them specifically for microarray data. Results We consider five such measures: Clest, Consensus (Consensus Clustering), FOM (Figure of Merit), Gap (Gap Statistics) and ME (Model Explorer), in addition to the classic WCSS (Within Cluster Sum-of-S…