Self-Similarity and Lamperti Convergence for Families of Stochastic Processes

We define a new type of self-similarity for one-parameter families of stochastic processes, which applies to a number of important families of processes that are not self-similar in the conventional sense. This includes a new class of fractional Hougaard motions defined as moving averages of Hougaard L\'evy process, as well as some well-known families of Hougaard L\'evy processes such as the Poisson processes, Brownian motions with drift, and the inverse Gaussian processes. Such families have many properties in common with ordinary self-similar processes, including the form of their covariance functions, and the fact that they appear as limits in a Lamperti-type limit theorem for families of stochastic processes.Comment: 23 pages. IMADA preprint 2010-09-0

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ECG Quality Assessment via Deep Learning and Data Augmentation

[EN] Quality assessment of ECG signals acquired with wearable devices is essential to avoid misdiagnosis of some cardiac disorders. For that purpose, novel deep learning algorithms have been recently proposed. However, training of these methods require large amount of data and public databases with annotated ECG samples are limited. Hence, the present work aims at validating the usefulness of a well-known data augmentation approach in this context of ECG quality assessment. Precisely, classification between high- and low-quality ECG excerpts achieved by a common convolutional neural network (CNN) trained on two databases has been compared. On the one hand, 2,000 5 second-length ECG excerpts were initially selected from a freely available database. Half of the segments were extracted from noisy ECG recordings and the other half from high-quality signals. On the other hand, using a data augmentation approach based on time-scale modification, noise addition, and pitch shifting of the original noisy ECG experts, 1,000 additional low-quality intervals were generated. These surrogate noisy signals and the original highquality ones formed the second dataset. The results for both cases were compared using a McNemar test and no statistically significant differences were noticed, thus suggesting that the synthesized noisy signals could be used for reliable training of CNN-based ECG quality indices.Huerta, Á.; Martínez-Rodrigo, A.; Rieta, JJ.; Alcaraz, R. (2021). ECG Quality Assessment via Deep Learning and Data Augmentation. 1-4. https://doi.org/10.22489/CinC.2021.2431

Genetic relationship of the Chiapas sheep breed with some spanish breeds

In the Southeastern part of Mexico, there are ovines descendent from Spanish ovines that were introduced in XVI century. The objective was to characterize ovine populations from Chiapas and the genetic distances with some Spanish breeds. 27 widely used microsatellites in biodiversity studies were employed in this research work. Ovines from Canary Islands were the more genetically distant from Mexicans. An algorithm inferring such admixture of genotypes of the population was used (one of de ancestors belongs to a different population). The number of inferred populations (K) was from 2 to 7 and the total number of iterations was 800000. When K=3, breeds from Chiapas were grouped, Palmera in another group and Merino, Sopravissana and Canaria in the third group. With K= 4. The breeds from Chiapas were once more grouped in a cluster, Merino and Sopravissana in a second group, Palmera and Canaria, were two independent clusters. For K=5. The breeds from Chiapas were grouped, and independent groups for the rest of breeds. With K=6 Chamula and Café remained together and with K=7 the program assigned to the breeds Chiapas, Chamula and Café in different clusters, but a remarkable influence from Chamula into Café is appreciated. The Palmera was partially divided in two clusters, showing that could exist individuals genetically different inside this population. The Borrego Chiapas has a vast individuality and genetic diversity.En el sureste de México existen ovinos que descienden de los ovinos españoles introducidos en el siglo XVI. El objetivo fue caracterizar las poblaciones ovinas de Chiapas y analizar las distancias genéticas con algunas poblaciones ovinas españolas. Se emplearon 27 microsatélites ampliamente utilizados en estudios de biodiversidad. Las ovejas de las Islas Canarias fueron las más distantes genéticamente de las de México. Se utilizó un algoritmo que infiere una mezcla de los genotipos de la población, es decir, que alguno de los ancestros pertenece a otra población. El número de poblaciones inferidas (K) fue de 2 a 7 y el número total iteraciones fue de 800000. Cuando K=2 el programa asignó en un cluster las razas Palmera y Canaria y en el otro todas las demás. Cuando K=3 se agruparon las chiapanecas, la Palmera sola y la Merino, Sopravissana y Canaria. Con K=4 se agruparon las chiapanecas en un cluster, la Merino y Sopravissana en otro y la Palmera y Canaria independientes. Con el valor de K=5, las de Chiapas se agruparon en uno y las otras cada una independiente. Con K=6 se mantuvieron unidas Chamula y Café y con K=7 el programa asignó a las razas Chiapas, Chamula y a la Café en clusters independientes, aunque se percibe una fuerte influencia de la Chamula en la Café. La Palmera quedó parcialmente dividida ente dos clusters, indicando que puede haber individuos genéticamente diferentes dentro de esta población. El Borrego Chiapas posee una gran individualidad y diversidad genéticas

Aclimatación al frío en diferentes clones de Eucalyptus globulus Labill durante el régimen natural de endurecimiento

En la región mediterránea la principal limitación de la expansión del las plantaciones de Eucalyptus es la ocurrencia periódica de temperaturas bajas durante los meses de invierno (-5 a -10 oC). Por esta razón es crucial implementar un programa para mejorar la resistencia al frío en las especies utilizadas de este género. E. globulus, la especie más extendida en la península ibérica es considerada una especie moderadamente susceptible al frío. Se testaron 16 clones a los cuales se les realizó un seguimiento durante el régimen natural de endurecimiento y la salida del mismo para el periodo 2005-2006. La tolerancia al frío fue evaluada en tejido foliar desarrollado, tanto en hojas pecioladas maduras como en hojas sentadas juveniles, simulando condiciones de helada en ambiente controlado. De esta forma se demostró que existe un proceso de aclimatación de las plantas a las bajas temperaturas a medida que se acumulan las horas de frío y una desaclimatación de las mismas a medida que acaba el invierno. En todos los clones se determinó un máximo de tolerancia para la segunda quincena de enero, lo que corresponde con un total acumulado de 415 horas de frío por debajo de los 7 oC (HF7). Por otra parte se observó un cambio significativo en el umbral de temperaturas que causan un daño al 50% de la superficie del tejido foliar (TL50), siendo el valor medio de éstas -4,5 ºC antes de comenzar la temporada de frío y de – 6,5 ºC una vez alcanzado el máximo de endurecimiento.______________________________The greatest constraint on the expansion of Eucalyptus plantations in the Mediterranean region is the periodic occurrence of low temperatures (–5 to –10 oC) during winter. This has raised the need to launch a programme aimed at increasing the tolerance to cold weather of Eucalyptus species in the region. Eucalyptus globulus, which is the most widespread Eucalyptus species in the Iberian peninsula, is moderately vulnerable to cold. In this work, a total of 16 clones of this species were monitored during their natural hardening regime and at its end over the period 2005–06. Tolerance to cold was evaluated in well-developed tissue of both mature petiolate leaves and seated young leaves by mimicking freezing conditions in a controlled environment. The plants were found to gradually acclimate to low temperatures as the number of cold hours increased and to de-acclimate as the winter neared its end. Tolerance in all clones peaked in the second half of January, after an overall 415 could hours at temperatures below 7 oC (HF7). Also, the temperature threshold below which at least 50% of leaf surface tissue was damaged (TL50) varied markedly, from an average –4.5 oC at the beginning of the cold season to an average –6.5 oC at the point of maximum hardening

Improved Discrimination Between Healthy and Hypertensive Individuals Combining Photoplethysmography and Electrocardiography

[EN] Cardiovascular disease is one of the leading causes of death, with hypertension (HT) being its main risk factor. Its complications can be avoided with early treatment, but since these patients do not present any symptoms, HT is often detected at very advanced stages. This work presents a model for estimating blood pressure (BP) from electrocardiographic (ECG) and photoplethysmographic (PPG) signals, which can be easily obtained by means of wearable continuous monitoring devices. ECG, PPG and BP recordings from 86 patients were analyzed.A total of 34 standard and new features based on previous works were defined, such as pulse arrival times (PAT), and morphological characteristics of PPG signal. 37 classification models, ranging from Logistic Regression, Support Vector Machines (SVM), Nearest Neighbors, Naive Bayes or Coarse Trees were trained to compare discrimination results. The classifier that provided the highest performance when comparing normotensive patients with prehypertensive and hypertensive patients were Coarse Tree, providing an F1 score of 85.44% (Se of 86.27% and Sp of 77.14%). The use of PPG and ECG features has successfully discriminated between healthy and hypertensive individuals and, thus, could be used to detect HT by embedding these techniques in wearable devices.Research supported by grants DPI2017¿83952¿C3 from MINECO/AEI/FEDER UE, SBPLY/17/180501/000411 from JCCLM and AICO/2021/286 from GVA.Cano, J.; Hornero, F.; Quesada, A.; Martínez-Rodrigo, A.; Alcaraz, R.; Rieta, JJ. (2021). Improved Discrimination Between Healthy and Hypertensive Individuals Combining Photoplethysmography and Electrocardiography. 1-4. https://doi.org/10.22489/CinC.2021.0301

Evaluation of metabolism and biosignaling in the angiogenic microenvironment as potential targets for therapeutic intervention

The "re-discovery" of Warburg effect at the turn of the present millennium has been a key determinant of the current renewed interest on cancer metabolism. In fact, metabolic reprogramming has been identified as one of the hallmarks of cancer. However, cancers grow in tight contact with non-tumoral accompanying cells and the surrounding extracellular matrix, as underlined by the concept of tumor microenvironment. Endothelial cells are key components of this tumor microenvironment, since they are requested for angiogenesis, another hallmark of cancer. In this complex system, rewiring of metabolism and signaling pathway in cancer, endothelial and other accompanying cell emerges as new potential targets for therapeutic intervention. In this communication, we will present the drug discovery and characterization approach of our group and our more recent results in this field, including new modeling with an evolutionary and ecological point of view.[Our experimental work is supported by grants BIO2014-56092-R (MINECO and FEDER) and P12-CTS-1507 (Andalusian Government and FEDER) and funds from group BIO-267 (Andalusian Government). The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain)]. This communication has the support of a travel grant "Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech"

Analysis of Sport Supplement Consumption by Competitive Swimmers According to Sex and Competitive Level.

Sports supplements (SS) are commonly used by athletes to improve their performance. SS use by competitive swimmers is reported to be prevalent but there is no evidence of such use by elite swimmers, either male or female. The objective of this research was to study the patterns of SS use by competitive swimmers based on sex and competitive levels (national and international); Methods: Using the categories of the Australian Institute of Sport (AIS), a total of 102 competitive swimmers (59 men and 43 women) completed a validated self-administered questionnaire on the use of SS; (3) Results: Overall, 86.9% of swimmers had consumed SSs with no differences observed between males and females (p = 0.247) or between competitive levels (p = 0.597). The SS that were most consumed by swimmers were caffeine (53.5%), sport drinks (52.5%), sport bars (51.5%), and vitamin C (43.4%). SSs categorized as medical supplements were consumed significantly more frequently by international swimmers (p = 0.012), with significant differences also found in the level—sex interaction (p = 0.049); (4) Conclusions: Compared to other sports disciplines, the prevalence of SS consumption is high in competitive swimmers regardless of performance level or gender. However, the consumption of medical supplements was greater in swimmers at a higher performance level.pre-print1202 K