Tilted excitation implies odd periodic resonances

This work was supported by the Brazilian agencies FAPESP and CNPq. MSB also acknowledges the Engineering and Physical Sciences Research Council grant Ref. EP/I032606/1. GID thanks Felipe A. C. Pereira for fruitful discussions.Peer reviewedPostprin

Experimental observation of a complex periodic window

The existence of a special periodic window in the two-dimensional parameter space of an experimental Chua's circuit is reported. One of the main reasons that makes such a window special is that the observation of one implies that other similar periodic windows must exist for other parameter values. However, such a window has never been experimentally observed, since its size in parameter space decreases exponentially with the period of the periodic attractor. This property imposes clear limitations for its experimental detection.Comment: 4.2 pages, 4 figure

Parameter space of experimental chaotic circuits with high-precision control parameters

ACKNOWLEDGMENTS The authors thank Professor Iberê Luiz Caldas for the suggestions and encouragement. The authors F.F.G.d.S., R.M.R., J.C.S., and H.A.A. acknowledge the Brazilian agency CNPq and state agencies FAPEMIG, FAPESP, and FAPESC, and M.S.B. also acknowledges the EPSRC Grant Ref. No. EP/I032606/1.Peer reviewedPublisher PD

Fried food intake estimated by the multiple source method is associated with gestational weight gain

AbstractThis present study aimed to test the association between fried food intake estimated by a semiquantitative food frequency questionnaire (FFQ), multiple 24-hour dietary recalls (24hRs), and the application of the multiple source method (MSM) in relation to gestational weight gain at the second and third trimesters and weight gain ratio (observed weight gain/expected weight gain). We hypothesized that distinct relationships with weight gain would be found given the measurement errors of self-reported dietary approaches. A prospective study was conducted with 88 adult pregnant women. Fried food intake during pregnancy was assessed using a validated 85-item FFQ, two to six 24hRs per woman, and the MSM with and without frequency of food intake as covariate. Linear regression models were used to evaluate the relationship between fried food estimated by the methods and weight gain. For every 100-g increment of fried food intake, the β (95% confidence interval) for weight gain was β 1.87 (0.34, 3.40) and β 2.00 0.55, 3.45) for estimates using MSM with and without the frequency of intake as covariate, respectively, after multiple adjustments. We found that fried food intake estimated by the FFQ and 24hRs β 0.40 (−0.68, 1.48) and β 0.49 (−0.53, 1.52), respectively, was unrelated to weight gain. In relation to weight gain ratio, a positive association was found for estimates using the MSM with [β 0.29 (0.03, 0.54)] and without the frequency of intake as covariate [β 0.31 (0.07, 0.55)]; and no associations were found for estimates by the FFQ or 24hRs. The data showed that fried food intake estimated the MSM, but not by the FFQ and 24hRs, is associated with excessive weight gain during pregnancy

Dynamical estimates of chaotic systems from Poincar\'e recurrences

We show that the probability distribution function that best fits the distribution of return times between two consecutive visits of a chaotic trajectory to finite size regions in phase space deviates from the exponential statistics by a small power-law term, a term that represents the deterministic manifestation of the dynamics, which can be easily experimentally detected and theoretically estimated. We also provide simpler and faster ways to calculate the positive Lyapunov exponents and the short-term correlation function by either realizing observations of higher probable returns or by calculating the eigenvalues of only one very especial unstable periodic orbit of low-period. Finally, we discuss how our approaches can be used to treat data coming from complex systems.Comment: subm. for publication. Accepted fpr publication in Chao

Nutritional Patterns, Anthropometric and Sociodemographic Aspects Associated with Gestational Diabetes Mellitus

Diabetes is the most frequent metabolic disorder during pregnancy. Its development is related to multiple factors and is associated with maternal and perinatal adverse effects. This study aims to determine the association of nutritional patterns, anthropometric and sociodemographic aspects with gestational diabetes mellitus (GDM), and perinatal results. A prospective cohort study was conducted on 237 pregnant women with the application of questionnaires: structured, global physical activity (GPAQ), 24-hour recall, and review of the perinatal medical history. Exploratory factor analysis was performed to determine the nutritional patterns; descriptive, bivariate, and multivariate analysis between the groups of patients with GDM and without GDM in users of the Centro de salud de Puengasí 2, and the Hospital Gineco Obstetrico Isidro Ayora in the city of Quito, from January to September 2021. Three nutritional patterns were identified in pregnant women. There was a difference in the variables, such as age, years of study, previous pregnancies, weight, and body mass index (BMI) for gestational age at the beginning of pregnancy between pregnant women diagnosed with GDM and those without GDM. Multivariate analysis confirms the association of GDM with BMI for gestational age at the start of pregnancy RR 0.293 (0.08-0.970) and passive smoking RR 0.037 (0.00196-0.701). No association with nutritional patterns was found. In conclusion,the affinity for nutritional patterns and physical activity does not show an association with GDM. The association between BMI for gestational age at the beginning of pregnancy and passive smoking with GDM is confirmed. Keywords: gestational diabetes mellitus, pregnancy, nutritional pattern, exercise. Resumen Introducción: La Diabetes es el trastorno metabólico mas frecuente durante la gestación, su desarrollo está relacionado a múltiples factores, y asociada a efectos adversos maternos y perinatales. Objetivo: Determinar la asociación de patrones nutricionales, aspectos antropométricos y sociodemográficos con el diagnóstico Diabetes Mellitus Gestacional (DMG) y resultados perinatales. Metodología: Estudio de cohorte prospectivo en 237 gestantes con la aplicación de cuestionarios: estructurado, global de actividad física (GPAQ), Recordatorio de 24 horas, y revisión de la historia clínica perinatal. Se realizó análisis factorial exploratorio para determinar los patrones nutricionales; análisis descriptivo, bivariado y multivariado entre los grupos de pacientes con DMG y sin DMG en usuarias del centro de salud Puengasí 2 y del Hospital Gineco-Obstétrico Isidro Ayora de la ciudad de Quito desde enero a septiembre 2021. Resultados: Se identificaron 3 patrones nutricionales en las gestantes. Hay diferencia en las variables: edad, años de estudio, gestas previas, peso e índice de masa corporal (IMC) para la edad gestacional al inicio del embarazo entre las gestantes con diagnóstico de DMG y sin DMG. El análisis multivariado confirma la asociación de DMG con el IMC para la edad gestacional al inicio del embarazo RR 0,293 (0,08- 0,970), y el tabaquismo pasivo RR 0,037 (0,00196-0,701). No se encontró asociación con los patrones nutricionales. Conclusiones: La afinidad por los patrones nutricionales y la actividad física no muestran asociación con DMG. Se confirma la asociación entre el IMC para la edad gestacional al inicio del embarazo y el tabaquismo pasivo con DMG. Palabras Clave: diabetes mellitus gestacional, gestación, patrón nutricional, ejercicio