Search results for "Separation"
showing 10 items of 865 documents
Atrial activity extraction for atrial fibrillation analysis using blind source separation.
2004
This contribution addresses the extraction of atrial activity (AA) from real electrocardiogram (ECG) recordings of atrial fibrillation (AF). We show the appropriateness of independent component analysis (ICA) to tackle this biomedical challenge when regarded as a blind source separation (BSS) problem. ICA is a statistical tool able to reconstruct the unobservable independent sources of bioelectric activity which generate, through instantaneous linear mixing, a measurable set of signals. The three key hypothesis that make ICA applicable in the present scenario are discussed and validated: 1) AA and ventricular activity (VA) are generated by sources of independent bioelectric activity; 2) AA …
Production and study of spinor condensates of <sup>87</sup>Rb released from a magnetic trap
2009
We report on our study of spinor condensates in the F=2 state of 87Rb produced in an atomic cloud expanding after releasing from a magnetic trap. The experiments are conducted in the setup described in Ref. [1].
Correction of the deviations in the retention times with Chromolith columns associated to the flow rate: Implications in the modelling of the retenti…
2011
In a previous work (J. Sep. Sci. 2009, 32, 2793-2803), we reported an interpretive optimisation approach to achieve maximal resolution in minimal analysis time, based on models describing the retention and peak shape as a function of mobile phase composition and flow rate. The method was applied to the separation of a group of basic drugs in a Chromolith column. In that work, we found that the retention factors were sensitive to the flow rate. The reason of the observed deviations in retention times is the increase in the column volume at the applied pressure, which decreases the linear velocity inside the column. This behaviour forced to include a correction term in the model that describe…
Encyclopedia of the Philosophy of Law and Social Philosophy
2021
In 1830, Belgian Catholics and Liberals had together adopted a constitution that declared the separation of church and state. The constitutional efforts of the Catholics in Belgium, Ireland, and Poland helped convince Hugues Felicite Lamennais (1782-1854) to give up his traditionalist demands in favor of liberal and democratic ones, which he defended in the journal L’Avenir (1830/31). Lamennais can be credited with being the first theorist to draw up a body of principles justifying from a Christian perspective a constitutional order that includes basic liberal rights and the separation of church and state.
Historical Overview of the Romanian Constitutionalism
2011
The history of the Romanian constitution and constitutionalism is closely linked to the 19th and 20th centuries. The 19th century meant the birth of the national unitary Romanian state and the building of the modern constitutional system by way of the massive constitutional transplant from the Western constitutional models. Breaking with the past was abrupt therefore just few ideas, institutions and practices remained as an organic linkage with the political and constitutional past.
Generalization of a finite-difference numerical method for the steady-state and transient solutions of the nernst—planck flux equations
1985
Abstract A generalization of the numerical method of Brumleve and Buck for the solution of Nernst—Planck equations when convective flux and electric current are involved has been developed. The simulation procedure was applied to a specific case: transport of strong electrolytes in a wide-pore membrane with simultaneous diffusion, convection and electric current. Good agreement was found between experimental data and computed results.
Quantifying brain tumor tissue abundance in HR-MAS spectra using non-negative blind source separation techniques
2012
Given high-resolution magic angle spinning (HR-MAS) spectra from several glial tumor subjects, our goal is to differentiate between tumor tissue types by separating the different sources that contribute to the profile of each spectrum. Blind source separation techniques are applied for obtaining characteristic profiles for necrosis, highly cellular tumor and border tumor tissue and providing the contribution (abundance) of each of these tumor tissue types to the profile of each spectrum. The problem is formulated as a non-negative source separation problem. Non-negative matrix factorization, convex analysis of non-negative sources and non-negative independent component analysis methods are …
Trace detection of plutonium by three-step photoionization with a laser system pumped by a copper vapor laser
1985
Laser photoionization has been used to detect trace amounts of plutonium. A high sensitivity and selectivity has been achieved by applying three-step excitation and ionization of the plutonium atoms with high pulse-repetition rates and additional mass determination by time-of-flight measurements. A laser system was developed which consists of a copper vapor laser pumping three dye lasers simultaneously. Samples containing between 1010 and 1012 atoms of239Pu on Re filaments were measured yielding strong resonance signals with maximum ion count rates of several kHz at a vanishingly low background. A detection efficiency of 10−7 was determined allowing the detection of about 108 plutonium atom…
MeCP2 haplodeficiency and early-life stress interaction on anxiety-like behavior in adolescent female mice
2021
Abstract Background Early-life stress can leave persistent epigenetic marks that may modulate vulnerability to psychiatric conditions later in life, including anxiety, depression and stress-related disorders. These are complex disorders with both environmental and genetic influences contributing to their etiology. Methyl-CpG Binding Protein 2 (MeCP2) has been attributed a key role in the control of neuronal activity-dependent gene expression and is a master regulator of experience-dependent epigenetic programming. Moreover, mutations in the MECP2 gene are the primary cause of Rett syndrome and, to a lesser extent, of a range of other major neurodevelopmental disorders. Here, we aim to study…
Non-analog decay of 74Rb
2001
The magnitude of the Coulomb mixing parameter δ1 IM has been experimentally deduced, for the first time, for the β decay of 74Rb. The estimated magnitude is derived from the feeding of the non-analog first excited 0+ state in 74Kr. The inferred upper limit of 0.07% is small compared to theoretical predictions. The half-life was measured to be 64.90(9) ms. peerReviewed