Comparison of Several Algorithms to Estimate Activity Counts with Smartphones as an Indication of Physical Activity Level

Background Dedicated devices like GT3X+, Actical or ActivPal have been widely used to measure physical activity (PA) levels by using cut-points on activity counts. However, the calculation of activity counts relies on proprietary software. Since smartphones incorporate accelerometers they are suitable candidates to determine PA levels in a wider population. Objective Our aim was to compare several algorithms so that smartphones can reproduce the results obtained with GT3X+. The influence of smartphone location was also investigated. Methods Volunteers participated in the experiment performing several activities carrying two smartphones (hip and pocket) and one GT3X+ (hip). Four algorithms (A1–A4) were considered to obtain GT3X+ counts from smartphone accelerometer signals. A1 was based on a traditional filtering on temporal domain and a posterior calculation of the area under the curve. A2 was based on computing histograms of acceleration values, which were used as independent variables in a standard linear regression procedure. A3 also used a linear regression, but in this case the independent variables were power spectrum bands, leading to a kind of filtering in the frequency domain. A4 was based on a direct measure of area under the rectified curve of the raw accelerometer signal. Performance was measured in terms of raw activity counts or the corresponding PA level classification. The influence of the algorithm was tested with a Quade test. Multiple comparisons were performed with Wilcoxon test with Bonferroni's correction. Besides, battery consumption was also measured as a secondary parameter. The output of the selected algorithm was compared with GT3X+ counts using correlation (pearson and spearman) and agreement (Intra-Class Coefficient, ICC and Bland–Altmann plots for raw counts, and weighted kappa for activity levels). Several experimental conditions regarding smartphone location were compared with Wilcoxon tests. Results Thirty-two volunteers participated in the experiment. More refined algorithms based on filtering techniques did not prove to achieve better performance than A2 or A4. In terms of classification of PA level, A4 got the lowest error rate, although in some cases the differences with other algorithms were not statistically significant (p-value > 0.05). A4 is also the simplest and the one that implies less battery depletion. The comparison of A4 with GT3X+ gave good agreement () and correlation () for raw counts and good agreement when classifying four or two PA levels ( or 0.923 respectively). Besides, in real situations, activity classification into four levels was significantly improved () if data from several body locations were used to find model parameters. Conclusions Simple algorithms can reproduce the results of GT3X+. Thus, smartphones could be used to control the fulfillment of PA recommendations previously validated with cut-points. However, it must be acknowledged that accelerometers are not the gold standard to measure PA

Ontogenesis of Gonadotropin-Releasing Hormone Neurons: A Model for Hypothalamic Neuroendocrine Cell Development

The vertebrate hypothalamo–pituitary–gonadal axis is the anatomical framework responsible for reproductive competence and species propagation. Essential to the coordinated actions of this three-tiered biological system is the fact that the regulatory inputs ultimately converge on the gonadotropin-releasing hormone (GnRH) neuronal system, which in rodents primarily resides in the preoptic/hypothalamic region. In this short review we will focus on: (1) the general embryonic temporal and spatial development of the rodent GnRH neuronal system, (2) the origin(s) of GnRH neurons, and (3) which transcription – and growth factors have been found to be critical for GnRH neuronal ontogenesis and cellular fate-specification. Moreover, we ask the question whether the molecular and cellular mechanisms involved in GnRH neuronal development may also play a role in the development of other hypophyseal secreting neuroendocrine cells in the hypothalamus

Longitudinal study of physical activity in college students: Testing self-determination theory based on stages of change

The main purpose of this study was to longitudinally test the relationships of Self Determination Theory variables on physical activity, analyzing the model based on stages of change. The study is a longitudinal and quantitative research. We have developed a longitudinal cross-lagged design for structural equation models of three time points and multi-group analysis. Participants were 772 Spanish college students from the University of Zaragoza (M = 19.74, SD = 2.76) studying several degrees. Participants completed different self-reports, assessing: physical activity, stages of change, motivation and basic psychological needs, at three time points (November, January and March). The analysis indicated that intrinsic motivation positively predicted physical activity at the 3-time points, both directly and indirectly. Intrinsic motivation was negatively predicted by autonomy and positively predicted by competence (from time point 2 to 3). No relationships were found with relatedness for the entire sample. Regarding the stages of change multi-group analysis were run: in the low active group, we found a negative relationship between relatedness and physical activity, and a positive association between competence and intrinsic motivation and physical activity, whereas intrinsic motivation did not predict physical activity. Our findings showed that intrinsic motivation was the most consistent predictor of physical activity. The competence need played an essential role in intrinsic motivation and physical activity for both active and passive subjects. However, the basic psychological needs have not worked as indicated by the theory when it was examined longitudinally. The findings of the study highlight the need for different strategies to improve physical activity levels according to the stages of change

Cumplimiento de las recomendaciones de práctica de actividad física en función de los cutoffs points y el género en estudiantes universitarios españoles

Los principales objetivos de este estudio fueron: a) estudiar los niveles de actividad física (AF) según los diferentes puntos de corte utilizados y el género; b) analizar el cumplimiento de las diferentes recomendaciones internacionales de AF según el género y puntos de corte. 95 universitarios, 33 hombres y 62 mujeres (21, 96 años + 2,33) llevaron acelerómetro para medir sus niveles de AF utilizando puntos de corte uniaxiales y triaxiales. Los resultados señalan mayores niveles de AF en los hombres para la AF vigorosa, pero no en la moderada. La mayoría de la muestra cumple con las recomendaciones de AF moderada, sin embargo, en la AF vigorosa el cumplimiento es bajo. El análisis de la AF con puntos de corte triaxiales son mayores a los uniaxiales, así como un mayor porcentaje de cumplimiento cuando se utilizan las recomendaciones establecidas por la Physical Activity Guidelines Advisory y la World Health Organization

Sedimentological and palaeohydrological characterization of Late Pleistocene and Holocene tufa mound palaeolakes using trenching methods in the Spanish Pyrenees

Lakes developed in the inner depressions of tufa mounds are rare geomorphic features and still poorly understood. Sedimentation in this unusual type of endorheic lake with a very restricted catchment area is highly sensitive to environmental and hydrological changes. The Isona tufa mound complex, north-eastern Iberian Peninsula, is associated with the discharge zone of a confined artesian aquifer and comprises 11 tufa mounds consisting of an annular rimstone enclosing a central depression filled with lake deposits. Data gathered from trenches excavated in four palaeolakes located within three different morphostratigraphic units permitted a precise analysis of the geometrical characteristics and stratigraphic relationships of the deposits and provided a sedimentation model for the Late Quaternary infilling of the spring-fed lakes. The work illustrates that trenches allow a precise characterization of the stratigraphic arrangements, lateral facies changes and deformation structures, which are not apparent in studies relying solely on borehole records, and facilitate sampling for dating and geochemical analyses. The five sedimentary facies described represent different evolutionary stages of the lakes, including: (i) carbonate-rich palustrine deposits probably related to periods with strong hydrological seasonality; (ii) massive highly bioturbated organic ooze; (iii) banded organic carbonate-rich facies associated with an increase in the regional effective moisture; (iv) finegrained quartz-rich aeolian/slope-wash sediments; and (v) colluvial facies deposited following the desiccation of the lakes located at higher altitudes. Geochemical and sedimentological analyses of the lacustrine sequences provided information on the palaeohydrological evolution of the Isona tufa mound complex and the palaeoenvironmental conditions of the area over the last 28 ka. Radiometric dating suggests that deposition occurred simultaneously at ca 22 ka in palaeolakes situated at different elevations. A drop in the piezometric level prompted by the opening of springs at lower altitudes probably caused the deactivation of the upper springs and the desiccation of the lakes. Arid conditions prevailed in the area during the Late Glacial and the early Holocene (28·0 to 8·5 ka BP). More humid conditions recorded from 8·5 to 4·2 ka and again since 1·7 ka are in accordance with palaeoenvironmental reconstructions available in the Western Mediterranean since the Last Glacial Maximum

Cumplimiento de las recomendaciones de práctica de actividad física en función de los cutoffs points y el género en estudiantes universitarios españoles

The main objectives of this study were: a) study the levels of physical activity (PA), according to the different cutoffs points used and gender; b) analyze the compliance of different international recommendations for physical activity by gender and cutoff points. 95 university students, 33 men and 62 women (21, 96 years) wore accelerometers to assess their levels of PA using uniaxial and triaxial cutoffs points. Results indicated higher PA levels in men in vigorous intensity, not in moderate. A high percentage of the sample fulfills the recommendations for moderate PA, nevertheless, for vigorous PA, it is low. Analyzes of PA with triaxial cutoffs points are higher than the uniaxial ones, besides a greatest compliance of PA recommendations of Physical Activity Guidelines Advisory (2008) and World Health Organization (2010) recommendations are used.Los principales objetivos de este estudio fueron: a) estudiar los niveles de actividad física (AF) según los diferentes puntos de corte utilizados y el género; b) analizar el cumplimiento de las diferentes recomendaciones internacionales de AF según el género y puntos de corte. 95 universitarios, 33 hombres y 62 mujeres (21, 96 años + 2,33) llevaron acelerómetro para medir sus niveles de AF utilizando puntos de corte uniaxiales y triaxiales. Los resultados señalan mayores niveles de AF en los hombres para la AF vigorosa, pero no en la moderada. La mayoría de la muestra cumple con las recomendaciones de AF moderada, sin embargo, en la AF vigorosa el cumplimiento es bajo. El análisis de la AF con puntos de corte triaxiales son mayores a los uniaxiales, así como un mayor porcentaje de cumplimiento cuando se utilizan las recomendaciones establecidas por la Physical Activity Guidelines Advisory y la World Health Organization

The Mediterranean diet protects against waist circumference enlargement in 12Ala carriers for the PPARgamma gene: 2 years' follow-up of 774 subjects at high cardiovascular risk.

The PPARgamma gene regulates insulin sensitivity and adipogenesis. The Pro12Ala polymorphism of this gene has been related to fat accumulation. Our aim was to analyse the effects of a 2-year nutritional intervention with Mediterranean-style diets on adiposity in high-cardiovascular risk patients depending on the Pro12Ala polymorphism of the PPARgamma gene. The population consisted of a substudy (774 high-risk subjects aged 55-80 years) of the Prevención con Dieta Mediterránea (PREDIMED) randomised trial aimed at assessing the effect of the Mediterranean diet for CVD prevention. There were three nutritional intervention groups: two of them of a Mediterranean-style diet and the third was a control group advised to follow a conventional low-fat diet. All the participants were genotyped by PCR-restriction fragment length polymorphism (RFLP). The results showed that carriers of the 12Ala allele allocated to the control group had a statistically significant higher change in waist circumference (adjusted difference coefficient = 2.37 cm; P = 0.014) compared with wild-type subjects after 2 years of nutritional intervention. This adverse effect was not observed among 12Ala carriers allocated to both Mediterranean diet groups. In diabetic patients a statistically significant interaction between Mediterranean diet and the 12Ala allele regarding waist circumference change was observed ( - 5.85 cm; P = 0.003). In conclusion, the Mediterranean diet seems to be able to reduce waist circumference in a high-cardiovascular risk population, reversing the negative effect that the 12Ala allele carriers of the PPARgamma gene appeared to have. The beneficial effect of this dietary pattern seems to be higher among type 2 diabetic subjects

Influence of the adherence to the Mediterranean diet on the effect of smoking on genomewide methylation among subjects with metabolic syndrome

Pòster presentat al congrés " Epigenetics: Playing with the Gameof Life" celebrat al University Hospital Halle (Saale) entre els dies 13-15 de 2019.Tobacco smoking is an important risk factor for lung cancer, respiratory diseases and cardiovascular diseases, among others. Moreover, smoking can speed up the normal aging process of several tissues increasing the biological age. Changes in methylation due to smoking have been demonstrated at several loci across the genome, particularly in long-term smokers (Figure 1). The most consistent association reported in different populations has been decreased methylation in smokers in comparison with non-smokers at the CpG cg05575921, located in the gene for the aryl hydrocarbon receptor repressor (AHRR) located in chromosome 5

The Gln241His polymorphism in the carbohydrate response element binding protein (MLXIPL) gene

Comunicació presentada com a pòster a European Association of Human Genetics Conference, May 23-26, 2009, Vien

EFECTOS DE LOS AMINOÁCIDOS EN LA PRODUCCIÓN DE CULTIVOS

Crop management is a changing and dynamic activity, which involves from the use of adapted cultivars to the use of stimulants products which help the plant tolerate stressful conditions. Abiotic factors in agroecosystems can generate challenges and significantly affect crop productivity; and the use of amino acids can help minimize these negative effects. Amino acids enhance biological processes of agronomic interest, giving crops different levels of resilience against stressful conditions such as high temperatures, drought conditions, high solar radiation, and salinity. However, is a lack of information and an objective dissemination with a scientific basis about the effects, benefits and efficiency of that products. The application of amino acids in crops can be spray or by drip irrigation, this practice saves energy in the plant, which can be transferred to the sinks, benefiting productivity. Furthermore, it also benefits the synthesis of extremely important compounds or enzymes, which provide plasticity at high temperatures. The effects of these substances are extensive, which in this review, interesting information is synthesized, as well as discussed from an agronomic perspective, with physiological support and crop metabolism. It is hoped that this review can contribute to unraveling the role of amino acids in a practical sense, as a reference for professionals in the management of agricultural systems and for the area of agronomic research.El manejo de cultivos es una actividad cambiante y dinámica, que involucra desde el uso de cultivares adaptados, hasta el uso de productos estimulantes que ayuden a la planta a tolerar condiciones estresantes. Factores bióticos en los agroecosistemas pueden generar desafíos y afectar significativamente la productividad de los cultivos; y el uso de aminoácidos puede ayudar a minimizar estos efectos negativos. Los aminoácidos potencializan procesos biológicos de interés agronómico, dando a los cultivos diferentes niveles de resiliencia ante condiciones estresantes, como las altas temperaturas, deficiencia hídrica, alta radiación solar, y salinidad. Sin embargo, aún existe escasez de información y falta de difusión objetiva con fundamento científico sobre los efectos, beneficios y eficiencia de estos productos. La aplicación de aminoácidos en cultivos puede ser foliar o en el riego por goteo, esta práctica economiza energía en la planta, que puede ser translocada hacia los sumideros, beneficiando la productividad. Además, favorece la síntesis de compuestos o enzimas de extrema importancia que confieren plasticidad ante altas temperaturas. Los efectos de los aminoácidos son amplios, por lo que, en esta revisión se sintetiza la información y se discute desde una perspectiva agronómica, con soporte fisiológico y del metabolismo de cultivos. Se espera que esta revisión pueda contribuir a desvendar el papel de los aminoácidos con sentido práctico, como referencia para profesionales en el manejo de sistemas agrícolas y para el área de la investigación agronómica