Miguel Arjona Ramírez

Learn More
Plasmodium vivax is the leading cause of human malaria in Asia and Latin America but is absent from most of central Africa due to the near fixation of a mutation that inhibits the expression of its receptor, the Duffy antigen, on human erythrocytes. The emergence of this protective allele is not understood because P. vivax is believed to have originated in(More)
Linear prediction (LP) analysis, split in two stages, is proposed for a combined time-frequency analysis. The first-stage LP is used to obtain the residual signal and extract each one of its cycles, whose harmonic spectrum is then modeled by the second-stage estimate from discrete all-pole algorithms. Thus, harmonic cycle spectra are modeled with less than(More)
The Malagarasi River has long been thought to be a barrier to chimpanzee movements in western Tanzania. This potential geographic boundary could affect chimpanzee ranging behavior, population connectivity and pathogen transmission, and thus has implications for conservation strategies and government policy. Indeed, based on mitochondrial DNA sequence(More)
Major histocompatibility complex (MHC) class I molecules determine immune responses to viral infections. These polymorphic cell-surface glycoproteins bind peptide antigens, forming ligands for cytotoxic T and natural killer cell receptors. Under pressure from rapidly evolving viruses, hominoid MHC class I molecules also evolve rapidly, becoming diverse and(More)
In this paper, we propose models for emotion recognition from speech based on class-dependent features and Gaussian mixture models (GMM). Seven emotions are identified (Happiness, Fear, Neutral, Disgust, Anger, Boredom and Sadness) with a small set of features for each class. Results show that our system outperforms the single-stage classifier, with a(More)
Vector quantization (VQ) of speech spectral vectors has been improved by techniques such as split VQ (SVQ), vector transforms and direction switching. This letter proposes Intra-Predictive Switched SVQ (IPSSVQ) with direction switching by a Gaussian Mixture Model (GMM), using at the frame level the prediction-based lower-triangular transform (PLT), which(More)
A method is proposed for split vector quantization (SVQ) that, while keeping up with the lower search complexity inherent to SVQ, reduces the attendant split loss. It operates partially in the training and encoding phases by normalizing the bandwidth covered by each split. The action is completed in the decoding phase by renormalizing the bandwidth spanned(More)