The effects of combined aerobic and resistance training on heart rate variability in postmenopausal women

Model of the study: Controlled clinical trial. Objective: To verify the effects of 16 weeks of combined aerobic and resistance training on cardiac autonomic modulation in menopausal women. Methods: 17 menopausal women were divided into two groups: the training group (TG: n=11) and control group (CG: n=6). The body composition variables were estimated using dual-energy X-ray absorptiometry. The cardiac autonomic modulation was evaluated by heart rate variability using linear indexes. The training protocol consisted of 16 weeks of 50 minutes of resistance training and 30 minutes of aerobic training. Results: For the TG there was an increase in the rMSSD(ms) index (pre:17,4±3,7 and post:24,8±13,1, p<0,045), an increase in the duration of the intervals between the cardiac beats(ms) (pre:891,2±80,2 and post:974,1±71,4, p<0,003) and in the values of heart rate(bpm) (pre:68,1±6,4 and post:62,0±4,7, p<0,003), additionally for the spectral indexes in normalized units, changes for LF (pre:52,2±13,1 and post:44,5±12,4, p<0,025) and HF (pre:47,8±13,3 and post:55,5±12,4, p<0,025) were noticed, demonstrating increased parasympathetic and reduced sympathetic. There were no significant differences to CG. Conclusion: combined aerobic and resistance training promoted benefits to the autonomic modulation in menopausal women.

A method for improving the code rate and error correction capability of a cyclic code

Currently, there has been an increasing demand for operational and trustworthy digital data transmission and storage systems. This demand has been augmented by the appearance of large-scale, high-speed data networks for the exchange, processing and storage of digital information in the different spheres. In this paper, we explore a way to achieve this goal. For given positive integers n,r, we establish that corresponding to a binary cyclic code C0[n,n-r], there is a binary cyclic code C[(n+1)3k-1,(n+1)3k-1-3kr], where k is a nonnegative integer, which plays a role in enhancing code rate and error correction capability. In the given scheme, the new code C is in fact responsible to carry data transmitted by C0. Consequently, a codeword of the code C0 can be encoded by the generator matrix of C and therefore this arrangement for transferring data offers a safe and swift mode. © 2013 SBMAC - Sociedade Brasileira de Matemática Aplicada e Computacional.

Resistance training for explosive and maximal strength: Effects on early and late rate of force development

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heart rate variability in children with type 1 diabetes mellitus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Integrative aspects of the relationship between stress and heart rate variability

The literature indicates stress as a response of the organism to a stimulation that requires enormous efforts to adapt to the changes in the environment and the body. When an individual is subjected to stress, the autonomic nervous system is triggered, the sympathetic pathway is activated, and the parasympathetic system is suppressed, which exerts several effects on the cardiovascular system and affects heart rate variability. This research aimed to conduct a literature review to find and analyze the studies that address clearly the implications of stress on heart rate variability. The methodology employed was an active search in the databases SciELO, PubMed and Lilacs. The results were five articles, most of which suggest a relationship between stress and heart rate variability. We observed that the majority of the studies indicated a strong association between stress and cardiac autonomic activity. The stress is present in the daily activities of the population, especially in labor. The subject is vast, however, were observed in the references the effects of stress on the body making it vulnerable to diseases. Thus, this information may contribute to the aid of preventive strategies against stress and diseases of the cardiovascular system.

Musical auditory stimulation at different intensities and its effects on the geometric indices of heart-rate variability

Introduction: Previous studies have shown that relaxation music increases the heart's parasympathetic modulation as well as reducing its sympathetic activity. However, what is lacking in the literature is information on the acute effects of different intensities of music on cardiac autonomic regulation. We aimed to evaluate the acute effects of baroque and heavy-metal music on cardiac autonomic regulation at different intensities. Method The study was performed in 16 healthy men aged between 18 and 25 years. The main outcomes were the geometric indices of heart-rate variability (HRV) [i.e. triangular index (RRtri); triangular interpolation of RR intervals (TINN) and Poincaré plot: SD1, SD2 and SD1/SD2 ratio]. First, HRV was recorded at rest for 10 min. The volunteers were then exposed to baroque or heavy-metal music for 5 min through an earphone; subjects were exposed to each song at three different sound levels (60–70, 70–80 and 80–90 decibels). After the first song, subjects remained at rest for 5 min before being exposed to the next song. The sequence of songs and sound intensity were randomised for each individual. Results Musical auditory stimulation with baroque music did not influence the geometric indices of HRV. The same was observed with heavy-metal musical auditory stimulation at the three sound-level ranges. Conclusion Musical auditory stimulation at different sound intensities did not influence the geometric indices of HRV in men.

Serological Diagnosis of Paracoccidioidomycosis: High Rate of Inter-laboratorial Variability among Medical Mycology Reference Centers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise da curva de resfriamento e refino de grão da liga de alumínio AA 356

The macrostructure of an alloy solidification in the raw state is of utmost importance due to its influence on mechanical properties. A structure showing columnar grains is generally undesirable in most applications of cast products and grain refining aims to suppress the formation of these grains and get a fine-grained equiaxed structure that improves the supply of liquid metal and the mechanical properties, as yield strength and tensile strength limit, as well as the tendency of formation of hot cracks. The type and size of grains formed are determined by chemical composition, cooling rate and the use of inoculum for grain refining. Titanium and boron are the major refiners in the aluminum industry and can be added to the molten metal in the form of alloys such as Al-Ti, Al-Ti-B or Al-B. In this paper we will discuss the information obtained from cooling curves and first derivative of the cooling curve to obtain the thermal parameters that influence the process of grain refining alloy AA 356.0

Temperature effects on baroreflex control of heart rate in the toad, Rhinella schneideri

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Image segmentation through combined methods: watershed transform, unsupervised distance learning and normalized cut

Research on image processing has shown that combining segmentation methods may lead to a solid approach to extract semantic information from different sort of images. Within this context, the Normalized Cut (NCut) is usually used as a final partitioning tool for graphs modeled in some chosen method. This work explores the Watershed Transform as a modeling tool, using different criteria of the hierarchical Watershed to convert an image into an adjacency graph. The Watershed is combined with an unsupervised distance learning step that redistributes the graph weights and redefines the Similarity matrix, before the final segmentation step using NCut. Adopting the Berkeley Segmentation Data Set and Benchmark as a background, our goal is to compare the results obtained for this method with previous work to validate its performance.

Can geometric indices of heart rate variability predict improvement in autonomic modulation after resistance training in chronic obstructive pulmonary disease?

Chronic obstructive pulmonary disease (COPD) is associated with autonomic dysfunctions that can be evaluated through heart rate variability (HRV). Resistance training promotes improvement in autonomic modulation; however, studies that evaluate this scenario using geometric indices, which include nonlinear evaluation, thus providing more accurate information for physiological interpretation of HRV, are unknown. This study aimed to investigate the influence of resistance training on autonomic modulation, using geometric indices of HRV, and peripheral muscle strength in individuals with COPD. Fourteen volunteers with COPD were submitted to resistance training consisting of 24 sessions lasting 60 min each, with a frequency of three times a week. The intensity was determined as 60% of one maximum repetition and was progressively increased until 80% for the upper and lower limbs. The HRV and dynamometry were performed at two moments, the beginning and the end of the experimental protocol. Significant increases were observed in the RRtri (4·81 ± 1·60 versus 6·55 ± 2·69, P = 0·033), TINN (65·36 ± 35·49 versus 101·07 ± 63·34, P = 0·028), SD1 (7·48 ± 3·17 versus 11·04 ± 6·45, P = 0·038) and SD2 (22·30 ± 8·56 versus 32·92 ± 18·78, P = 0·022) indices after the resistance training. Visual analysis of the Poincare plot demonstrated greater dispersion beat-to-beat and in the long-term interval between consecutive heart beats. Regarding muscle strength, there was a significant increase in the shoulder abduction and knee flexion. In conclusion, geometric indices of HRV can predict improvement in autonomic modulation after resistance training in individuals with COPD; improvement in peripheral muscle strength in patients with COPD was also observed.

Glutamatergic neurotransmission in the hypothalamus PVN on heart rate variability in exercise trained rats

The paraventricular nucleus of hypothalamus (PVN) is a well known site of integration for autonomic and cardiovascular responses, and the glutamate neurotransmitter plays an important role. The aim of our study was to evaluate the cardiovascular parameters and autonomic modulation by means of spectral analysis after ionotropic glutamate receptor inhibition in the PVN in conscious sedentary (S) or swimming trained (ST) rats. After exercise training protocol, adult male Wistar rats, instrumented with guide cannulae to PVN and artery and vein catheters were submitted to mean arterial pressure (MAP) and heart rate (HR) recording. At baseline, physical training induced a resting bradycardia (S: 379 +/- 3, ST: 349 +/- 2 bpm, P<0.05) and promoted adaptations in HRV characterized by an increase of HF in normalized values and a decrease of LF in absolute and normalized units compared with the sedentary group. Microinjection of kynurenic acid (KYNA) in the PVN of sedentary and trained rats promoted decreases in MAP and HR, but the decrease in HR was smaller in the trained animals (Delta HRS: -48 +/- 7, ST: -28 +/- 4 bpm, P<0.05). Furthermore, the differences in baseline parameters of pulse interval, found between sedentary and trained animals, disappeared after KYNA microinjection in the PVN. Our data suggest that the cardiovascular and autonomic adaptations to the heart induced by exercise training may involve glutamatergic mechanisms in the PVN. (C) 2012 Elsevier B.V. All rights reserved.

Penetrance rate estimation in autosomal dominant conditions

Accurate estimates of the penetrance rate of autosomal dominant conditions are important, among other issues, for optimizing recurrence risks in genetic counseling. The present work on penetrance rate estimation from pedigree data considers the following situations: 1) estimation of the penetrance rate K (brief review of the method); 2) construction of exact credible intervals for K estimates; 3) specificity and heterogeneity issues; 4) penetrance rate estimates obtained through molecular testing of families; 5) lack of information about the phenotype of the pedigree generator; 6) genealogies containing grouped parent-offspring information; 7) ascertainment issues responsible for the inflation of K estimates.

Aging reduces complexity of heart rate variability assessed by conditional entropy and symbolic analysis

Increasing age is associated with a reduction in overall heart rate variability as well as changes in complexity of physiologic dynamics. The aim of this study was to verify if the alterations in autonomic modulation of heart rate caused by the aging process could be detected by Shannon entropy (SE), conditional entropy (CE) and symbolic analysis (SA). Complexity analysis was carried out in 44 healthy subjects divided into two groups: old (n = 23, 63 +/- A 3 years) and young group (n = 21, 23 +/- A 2). It was analyzed SE, CE [complexity index (CI) and normalized CI (NCI)] and SA (0V, 1V, 2LV and 2ULV patterns) during short heart period series (200 cardiac beats) derived from ECG recordings during 15 min of rest in a supine position. The sequences characterized by three heart periods with no significant variations (0V), and that with two significant unlike variations (2ULV) reflect changes in sympathetic and vagal modulation, respectively. The unpaired t test (or Mann-Whitney rank sum test when appropriate) was used in the statistical analysis. In the aging process, the distributions of patterns (SE) remain similar to young subjects. However, the regularity is significantly different; the patterns are more repetitive in the old group (a decrease of CI and NCI). The amounts of pattern types are different: 0V is increased and 2LV and 2ULV are reduced in the old group. These differences indicate marked change of autonomic regulation. The CE and SA are feasible techniques to detect alteration in autonomic control of heart rate in the old group.

Records of sedimentary dynamics in the continental shelf and upper slope between Aveiro-Espinho (N Portugal)

The sedimentary unconsolidated cover of the Aveiro-Espinho continental shelf and upper slope (NW Portugal) records a complex interplay of processes including wave energy and currents, fluvial input, sediment transport alongshore and cross-shelf, geological and oceanographic processes and sediment sources and sinks. In order to study this record, a set of surface sediment samples was studied. Sediment grain size and composition, as well as the mineralogical composition (by XRD) of the fine (<63 mu m) and clay (<2 mu m) fractions and benthic microfaunal (foraminifera) data were analysed. Cluster analysis applied to the sedimentological data (grain size, sediment composition and mineralogy) allowed the establishment of three main zones corresponding to the: inner-, mid- and outer-shelf/upper slope. On the inner-shelf, the sedimentary coverture is composed of siliciclastic fine to very fine sand, essentially comprising modern (immature) terrigenous particles. The sediment grain size, as well as mineralogical and microfaunal composition, denote the high energetic conditions of this sector in which the alongshore transport of sand is predominantly southward and occurs mostly during the spring-summer oceanographic regime, when the main river providing sediments to this area, the River Douro, undergoes periods of drought. This effect may emphasize the erosive character of this coastal sector at present, since the Ria de Aveiro provides the shelf with few sediments. On the mid-shelf, an alongshore siliciclastic band of coarse sand and gravel can be found between the 40 m and 60 m isobaths. This gravelly deposit includes relic sediments deposited during lower sea-level stands. This structure stays on the surface due to the high bottom energy, which promotes the remobilization of the fine-grained sediments, and/or events of sediments bypassing. Benthic foraminifera density and "Benthic Foraminifera High Productivity" (BFHP) proxy values are in general low, which is consistent with the overall small supply of organic matter to the oceanic bottom in the inner- and mid-shelf. However, the Ria de Aveiro outflow, which delivers organic matter to the shelf, leaves its imprint mainly on the mid-shelf, identifiable by the increase in foraminifera density and BFHP values in front of the lagoon mouth. The higher values of BFHP along the 100 m isobath trace the present position of an oceanic thermal front whose situation may have changed in the last 3/5 ka BP. This zone marks a clear difference in the density, diversity and composition of benthic foraminifera assemblages. Here, in addition, sediment composition changes significantly, giving rise to carbonate-rich fine to medium sand in the deeper sector. The low bottom energy and the small sedimentation rate of the outer-shelf contributed to the preservation of a discontinuous carbonate-rich gravel band, between the 100 m and 140 m isobaths, also related to paleo-littorals, following the transgression that has occurred since the Last Glacial Maximum. The winter oceanographic regime favours the transport of fine grained sediments to the outer-shelf and upper slope. The inner- and mid-shelf, however, have low amounts of this kind of sediment and the Cretacic carbonated complexes Pontal da Galega and Pontal da Cartola, rocky outcrops located at the mid- and outer-shelf, act as morphological barriers to the cross-shelf transport of sediments. Thus a reduced sedimentation rate occurs in these deeper sectors, as indicated by the lower abundance of detrital minerals, which is compensated for the high sedimentary content of biogenic carbonates. The relatively high BFHP and Shannon Index values indicate water column stratification, high supply of organic matter and environmental stability, which provide favourable conditions for a diversified benthic fauna to flourish. These conditions also encourage authigenic chemical changes, favourable to glauconite formation, as well as illite and kaolinite degradation. Benthic foraminifera and clay mineral assemblages also reveal the effect of the internal waves pushing upward, and downslope losses of the sediments on the outer-shelf and upper slope.