Exercise and lifestyle predictors of resting heart rate in healthy young adults

Physical exercise is well-understood to provide significant health benefits, through physiological adaptations induced by the repeated exertion stress exercise imposes on our systems. Chief among these are cardiovascular adaptations to exercise, including adjustments of cardiac parameters such as stroke volume, heart rate, and maximal cardiac output. It is commonly assumed that aerobic forms of exercise provide greater cardiovascular benefits than do non-aerobic forms of exercise. To test this assumption, exercise habits and resting heart rate were examined in a large population of healthy young adults. 90% of subjects reported regular physical exercise, with aerobic exercise constituting 64% of all exercise hours. Subjects with a history of smoking exhibited higher resting heart rates than those with no smoking history, an effect which was due primarily to a reduction in exercise hours by smokers than due to a smoking habit itself. While both total exercise amount and aerobic exercise amount were significantly and negatively related to resting heart rate, total exercise amount was a better overall predictor of resting heart rate than was aerobic exercise amount. All forms of exercise were associated with cardiovascular health, with cardiovascular benefits accruing according to the amount of exercise performed, even in optimally healthy young adults

Exercise and lifestyle predictors of resting heart rate in healthy young adults

Physical exercise is well-understood to provide significant health benefits, through physiological adaptations induced by the repeated exertion stress exercise imposes on our systems.  Chief among these are cardiovascular adaptations to exercise, including adjustments of cardiac parameters such as stroke volume, heart rate, and maximal cardiac output.  It is commonly assumed that aerobic forms of exercise provide greater cardiovascular benefits than do non-aerobic forms of exercise.  To test this assumption, exercise habits and resting heart rate were examined in a large population of healthy young adults.  90% of subjects reported regular physical exercise, with aerobic exercise constituting 64% of all exercise hours.  Subjects with a history of smoking exhibited higher resting heart rates than those with no smoking history, an effect which was due primarily to a reduction in exercise hours by smokers than due to a smoking habit itself.  While both total exercise amount and aerobic exercise amount were significantly and negatively related to resting heart rate, total exercise amount was a better overall predictor of resting heart rate than was aerobic exercise amount.  All forms of exercise were associated with cardiovascular health, with cardiovascular benefits accruing according to the amount of exercise performed, even in optimally healthy young adults

Differential GO and NO GO Learning Within an Auditory Discrimination Task

Animal discrimination training and testing often are used to assess animal behavioral flexibility and capabilities. GO-NOGO discrimination, in particular, has been used extensively, across a multitude of species and experimental paradigms. In its typical form, GO-NOGO discrimination learning is assessed by the magnitude of, and rate of acquisition of, discrimination capability, which is nominally low at the start of training, and through experience, is improved as a function of the reward schedule employed. Discrimination performance in this task is normally reported via a single empirical metric, as the percentage of stimulus-response trials which included a ‘correct’ response. However, this view of discrimination as a singular skill masks the considerable differences which exist in GO and NOGO responses (which typically require an action, and a suppression of action, respectively). To investigate the potential for these two responses to be learned independently and via different mechanisms, we performed operant training of adult zebra finches (Taeniopygia guttata) in a GO-NOGO auditory discrimination task. We demonstrate that correct responsiveness to GO and NOGO stimuli was learned via different overall performance trajectories, with performance on GO and NOGO trials emerging independently both within and between training sessions. We propose that this differential learning derives from a combination of response generalization and response modal form. These data suggest that response action and suppression are subserved by different neural circuits, and further indicate that consideration of discrimination tasks as univariate problems masks underlying complexity by obscuring their individual components

Efficient C2 Continuous Surface Creation Technique Based on Ordinary Differential Equation

In order to reduce the data size and simplify the process of creating characters’ 3D models, a new and interactive ordinary differential equation (ODE)-based C2 continuous surface creation algorithm is introduced in this paper. With this approach, the creation of a three-dimensional surface is transformed into generating two boundary curves plus four control curves and solving a vector-valued sixth order ordinary differential equation subjected to boundary constraints consisting of boundary curves, and first and second partial derivatives at the boundary curves. Unlike the existing patch modeling approaches which require tedious and time-consuming manual operations to stitch two separate patches together to achieve continuity between two stitched patches, the proposed technique maintains the C2 continuity between adjacent surface patches naturally, which avoids manual stitching operations. Besides, compared with polygon surface modeling, our ODE C2 surface creation method can significantly reduce and compress the data size, deform the surface easily by simply changing the first and second partial derivatives, and shape control parameters instead of manipulating loads of polygon points

Comparative neuroanatomy of song performance in the Carolina wren Thryothorus ludovicianus

This research addresses the scaling of neural investment and behavioral complexity in the avian song system. Prior analyses demonstrated that the size of premotor song control regions (SCR) is related to the size of the song repertoire performed, suggesting that SCR size conveys functional capability. Here, detailed measures of singing behavior and its neuroanatomical basis in the Carolina wren Thryothorus ludovicianus are presented. This species was chosen for its potential to inform comparative studies relating brain and behavior at multiple levels of analysis; evaluations of brain:behavior scaling within this species (intra- and intersexual), as well as interspecific comparisons within the genus, are presented. Behavioral measures include estimates of repertoire sizes, as well as measures of song output and type-switching during singing. Objective methods for evaluating the syllabic structure of song are also presented. Neuroanatomical measures were based on nuclei HVc and RA in the song motor pathway, and include measures of neuron size and density. An immunohistochemical method for evaluating synapse density is also presented. The distinct syllable “types” of the Carolina wren song repertoire are shown to contain multiple, stable “forms”; this result requires reconsideration of the actual unit of learning and production (song “type” versus “form”). Song system synapse density estimates from males of two species having song repertoires of very different size were equivalent, suggesting that synapse density is not a marker of repertoire diversity. The relationship between neural investment in SCR and song repertoire size differs markedly among levels of analytical scale. Nearly all aspects of SCR cytoarchitecture differ between singing males and non-singing females, suggesting that neural investment is scaled inter-sexually to the performance of song. However, these same neuroanatomical measures fail to explain variation in singing behavior among individual males, suggesting that neural investment and singing behavior are uncoupled at this level. Nonetheless, overall SCR volume, as well as nucleus RA neuron size and density, are related to song repertoire size among species within this genus. This “taxon level effect” suggests that the factors relating brain and behavior in this genus do not act similarly within and among species

Comparative neuroanatomy of song performance in the Carolina wren Thryothorus ludovicianus

This research addresses the scaling of neural investment and behavioral complexity in the avian song system. Prior analyses demonstrated that the size of premotor song control regions (SCR) is related to the size of the song repertoire performed, suggesting that SCR size conveys functional capability. Here, detailed measures of singing behavior and its neuroanatomical basis in the Carolina wren Thryothorus ludovicianus are presented. This species was chosen for its potential to inform comparative studies relating brain and behavior at multiple levels of analysis; evaluations of brain:behavior scaling within this species (intra- and intersexual), as well as interspecific comparisons within the genus, are presented. Behavioral measures include estimates of repertoire sizes, as well as measures of song output and type-switching during singing. Objective methods for evaluating the syllabic structure of song are also presented. Neuroanatomical measures were based on nuclei HVc and RA in the song motor pathway, and include measures of neuron size and density. An immunohistochemical method for evaluating synapse density is also presented. The distinct syllable “types” of the Carolina wren song repertoire are shown to contain multiple, stable “forms”; this result requires reconsideration of the actual unit of learning and production (song “type” versus “form”). Song system synapse density estimates from males of two species having song repertoires of very different size were equivalent, suggesting that synapse density is not a marker of repertoire diversity. The relationship between neural investment in SCR and song repertoire size differs markedly among levels of analytical scale. Nearly all aspects of SCR cytoarchitecture differ between singing males and non-singing females, suggesting that neural investment is scaled inter-sexually to the performance of song. However, these same neuroanatomical measures fail to explain variation in singing behavior among individual males, suggesting that neural investment and singing behavior are uncoupled at this level. Nonetheless, overall SCR volume, as well as nucleus RA neuron size and density, are related to song repertoire size among species within this genus. This “taxon level effect” suggests that the factors relating brain and behavior in this genus do not act similarly within and among species

Northern Cardinal Sexes Defend Nests Equally

Volume: 109Start Page: 269End Page: 27