Rebeca Romo-Vázquez

Genomic Signal Processing Methods for Computation of Alignment-Free Distances from DNA Sequences

Genomic signal processing (GSP) refers to the use of digital signal processing (DSP) tools for analyzing genomic data such as DNA sequences. A possible application of GSP that has not been fully explored is the computation of the distance between a pair of sequences. In this work we present GAFD, a novel GSP alignment-free distance computation method. We introduce a DNA sequence-to-signal mapping function based on the employment of doublet values, which increases the number of possible amplitude values for the generated signal. Additionally, we explore the use of three DSP distance metrics as descriptors for categorizing DNA signal fragments. Our results indicate the feasibility of employing GAFD for computing sequence distances and the use of descriptors for characterizing DNA fragments.

Is sex an influential factor in type-1 diabetes neurofunctional development? A preliminary study

The aim of the study was to evaluate the neurofunctional effect of gender in Type‐1 Diabetes Mellitus (T1DM) patients during a Visual Spatial Working Memory (VSWM) task. The study included 28 participants with ages ranging from 17‐28 years. Fourteen well‐controlled T1DM patients (7 female) and 14 controls matched by age, sex, and education level were scanned performing a block‐design VSWM paradigm. Behavioral descriptive analyses and mean comparisons were done, and between‐group and condition functional activation patterns were also compared. Whole‐brain cumulative BOLD signal (CumBS), voxel‐wise BOLD level frequency, Euclidean distance, and divergence indices were also calculated. There were no significant differences between or within‐group sex differences for correct responses and reaction times. Functional activation analyses showed that females had activation in more brain regions, and with larger clusters of cortical activations than males. Furthermore, BOLD activation was higher in males. Despite the preliminary nature of the present study given the relatively small sample size, current results acknowledge for the first time that sex might contribute to differences in functional activation in T1DM patients. Findings suggest that sex differences should be considered when studying T1DM‐disease development.

The analysis of EEG coherence reflects middle childhood differences in mathematical achievement

HIGHLIGHTSSymbolic‐numeric comparison lies on complex brain functional interacting networks.EEG coherence analysis depict functional brain activation underlying math skills.Children with lower math skills need more attentional control & processing resources.Brain functional connectivity discerns between high and low math skills in children. ABSTRACT Symbolic numerical magnitude processing is crucial to arithmetic development, and it is thought to be supported by the functional activation of several brain‐interconnected structures. In this context, EEG beta oscillations have been recently associated with attention and working memory processing that underlie math achievement. Due to that EEG coherence represents a useful measure of brain functional connectivity, we aimed to contrast the EEG coherence in forty 8‐to‐9‐year‐old children with different math skill levels (High: HA, and Low achievement: LA) according to their arithmetic scores in the Fourth Edition of the Wide Range Achievement Test (WRAT‐4) while performing a symbolic magnitude comparison task (i.e. determining which of two numbers is numerically larger). The analysis showed significantly greater coherence over the right hemisphere in the two groups, but with a distinctive connectivity pattern. Whereas functional connectivity in the HA group was predominant in parietal areas, especially involving beta frequencies, the LA group showed more extensive frontoparietal relationships, with higher participation of delta, theta and alpha band frequencies, along with a distinct time–frequency domain expression. The results seem to reflect that lower math achievements in children mainly associate with cognitive processing steps beyond stimulus encoding, along with the need of further attentional resources and cognitive control than their peers, suggesting a lower degree of numerical processing automation.

Noncoding sequence classification based on wavelet transform analysis: part II

DNA sequences in human genome can be divided into the coding and noncoding ones. Coding sequences are those that are read during the transcription. The identification of coding sequences has been widely reported in literature due to its much-studied periodicity. Noncoding sequences represent the majority of the human genome. They play an important role in gene regulation and differentiation among the cells. However, noncoding sequences do not exhibit periodicities that correlate to their functions. The ENCODE (Encyclopedia of DNA elements) and Epigenomic Roadmap Project projects have cataloged the human noncoding sequences into specific functions. We study characteristics of noncoding sequences with wavelet analysis of genomic signals.

Vibrotactile Discrimination Training Affects Brain Connectivity in Profoundly Deaf Individuals

Early auditory deprivation has serious neurodevelopmental and cognitive repercussions largely derived from impoverished and delayed language acquisition. These conditions may be associated with early changes in brain connectivity. Vibrotactile stimulation is a sensory substitution method that allows perception and discrimination of sound, and even speech. To clarify the efficacy of this approach, a vibrotactile oddball task with 700 and 900 Hz pure-tones as stimuli [counterbalanced as target (T: 20% of the total) and non-target (NT: 80%)] with simultaneous EEG recording was performed by 14 profoundly deaf and 14 normal-hearing (NH) subjects, before and after a short training period (five 1-h sessions; in 2.5–3 weeks). A small device worn on the right index finger delivered sound-wave stimuli. The training included discrimination of pure tone frequency and duration, and more complex natural sounds. A significant P300 amplitude increase and behavioral improvement was observed in both deaf and normal subjects, with no between group differences. However, a P3 with larger scalp distribution over parietal cortical areas and lateralized to the right was observed in the profoundly deaf. A graph theory analysis showed that brief training significantly increased fronto-central brain connectivity in deaf subjects, but not in NH subjects. Together, ERP tools and graph methods depicted the different functional brain dynamic in deaf and NH individuals, underlying the temporary engagement of the cognitive resources demanded by the task. Our findings showed that the index-fingertip somatosensory mechanoreceptors can discriminate sounds. Further studies are necessary to clarify brain connectivity dynamics associated with the performance of vibrotactile language-related discrimination tasks and the effect of lengthier training programs.

La separación ciega de fuentes: un puente entre el álgebra lineal y el análisis de señales

El objetivo de este articulo es presentar un analisis praxeologico enmarcado en la Teoria Antropologica de lo Didactico (TAD) de un metodo proveniente de la ingenieria conocido como Separacion Ciega de Fuentes (BSS). En el metodo estan presentes praxeologias que pueden trasponerse a los cursos iniciales de matematicas dentro de una formacion de ingenieros, concretamen- te dentro del curso de Algebra Lineal. El analisis muestra que la BSS tiene potencial para generar actividades de modelacion que conecten la teoria mate- matica con la practica ingenieril. Se presenta, ademas, una propuesta inicial para una actividad de estudio e investigacion basada en la BSS.