14 research outputs found
Measurements design and phenomena discrimination
The construction of measurements suitable for discriminating signal
components produced by phenomena of different types is considered. The required
measurements should be capable of cancelling out those signal components which
are to be ignored when focusing on a phenomenon of interest. Under the
hypothesis that the subspaces hosting the signal components produced by each
phenomenon are complementary, their discrimination is accomplished by
measurements giving rise to the appropriate oblique projector operator. The
subspace onto which the operator should project is selected by nonlinear
techniques in line with adaptive pursuit strategies
Constructive updating/downdating of oblique projectors: a generalization of the Gram-Schmidt process
A generalization of the Gram-Schmidt procedure is achieved by providing
equations for updating and downdating oblique projectors. The work is motivated
by the problem of adaptive signal representation outside the orthogonal basis
setting. The proposed techniques are shown to be relevant to the problem of
discriminating signals produced by different phenomena when the order of the
signal model needs to be adjusted.Comment: As it will appear in Journal of Physics A: Mathematical and
Theoretical (2007
Analysis of error propagation in the ABS class for linear systems
Backward error analysis, optimally stable method,
Synthesis and physicochemical characterization of cyclic laminin related peptides
Tbe synthesis of three cyclic peptides related to an active sequence of Laminin is described. These molecules have no, one, or two stearoyl residues linked to the amino terminal end of the sequence. The physicochemical properties of these peptides as well as their interactions with dipalmitoylphosphatidylcholine molecules ordered in mono- and bilayers are described. Properties based on aqueous solutions of peptides show maximum activity for the analogue with one stearoyl residue. But properties measured from organic solutions of peptides (compression isotherms), as well as those in water but at high temperatures, gave as the most surface active the distearoyl derivative. This behavior is interpreted as a strong tendency of this highly Hydrophobic molecule to form aggregates (probably micelles), very stable in aqueous media. Thus, the monostearoyl-substituted peptide seems to be the most adequate for efficient insertion into mono- and bilayers.Peer reviewe
The role of ABC-transporter gene polymorphisms in chemotherapy induced immunosuppression, a retrospective study in childhood acute lymphoblastic leukaemia
We examined the association of functional ABCB1 (MDR1) and ABCG2 (BCRP)
polymorphisms with acute side effects of chemotherapy. Analyses were performed on
clinical data from 138 patients treated with the ALL-BFM-95 protocol implying
several substrates of these transporters. ABCB1 3435T>C, 2677G>T/A 1236C>T and
ABCG2 421C>A genotypes were determined. A higher proportion of ABCB1 3435TT
patients suffered excessive infectious complications than those harbouring at
least one C allele (OR=2.5, p=0.03) during the whole half-year-long intensive
phase of chemotherapy. Weaker associations were calculated when ABCB1
1236T-2677T-3435T haplotype homozygotes were tested against the remaining part of
the population (OR=2.3, p=0.09). During the reinduction phase of therapy, the
occurrence of severe leukocytopenia was similar among ABCB1 genotype groups. The
frequency of any toxicities were not shown to differ according to the ABCG2
421C>A genotype. Our data suggest that the ABCB1 3435T>C genotype is associated
with the infectious complications of the applied chemotherapy regimen