Représentation des mots et des non-mots en mémoire visuelle à court terme : évidence provenant de l'électrophysiologie humaine

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Sex moderates the effect of aerobic exercise on some aspects of cognition in cognitively intact younger and middle-age adults

We recently reported the results of a randomized, parallel-group, observer-masked, community-based clinical trial of 132 cognitively normal individuals aged 20–67 with below median aerobic capacity who were randomly assigned to one of two 6-month, four-times-weekly conditions: aerobic exercise and stretching/toning. We now assessed potential sex moderation on exercise-related changes in aerobic capacity, BMI and cognitive function. There was no sex moderation of the effect of aerobic exercise on aerobic capacity or BMI. We had previously reported an effect of aerobic exercise on executive function that was moderated by age. We found additional moderation by sex, such that in any age range men improved more than women. Processing speed showed significant sex moderation but not significant age moderation. In men, processing speed significantly improved by week 12 (b = 0.35, p = 0.0051), but the effect was diminished relative to week 12 at week 24 (b = 0.24, p = 0.0578). In women, there was no exercise effect at either time point (week 12: b = −0.06, p = 0.4156; week 24: b = −0.11, p = 0.1841). Men benefited cognitively more than women from aerobic exercise. This study highlights the importance of using sex-disaggregated analyses when assessing the impact of physical exercise intervention, and the need to ascertain the underlying mechanisms for differential cognitive benefit by sex

Effects of Dance/Movement Training vs. Aerobic Exercise Training on cognition, physical fitness and quality of life in older adults: A randomized controlled trial

It is generally accepted that physical activity promotes healthy aging. Recent studies suggest dance could also benefit cognition and physical health in seniors, but many styles and approaches of dance exist and rigorous designs for intervention studies are still scarce. The aim of this study was to compare the effects of Dance/Movement Training (DMT) to Aerobic Exercise Training (AET) on cognition, physical fitness and health-related quality of life in healthy inactive elderly. Results suggest that DMT may have a positive impact on cognition and physical functioning in older adults however further research is needed. This study could serve as a model for designing future RCTs with dance-related interventions

Application of discrete Fourier transform in information transmission by OFDM modulation

Frekvencijski multipleks ortogonalnih podnosilaca − OFDM predstavlja moćnu modulacijsku tehniku sposobnu za visoku brzinu prijenosa podataka u uvjetima vremenski disperzivnih bežičnih komunikacijskih kanala. Njegova robusnost na međusimbolnu i međukanalnu interferenciju ˇčini ga nezamjenjivim u modernim komunikacijskim sustavim. Korištenje brze Fourierove transformacije čini implementaciju OFDM sustava komputacijski jako efikasnom. U ovom radu opisana je diskretna Fourierova transformacija te je izveden algoritam brze Fourierove transformacije. U Matlab programskom paketu simuliran je OFDM primopredajnik gdje su se koristile QPSK i QAM modulacijske tehnike.Orthogonal frequency division multiplexing - OFDM is a powerful modulation technique capable of high speed data transmission in the conditions of time-dispersive wireless communication channels. Its robustness to intersymbol and interchannel interference makes it indispensable in modern communication systems. The use of fast Fourier transform makes the implementation of OFDM systems computationally very efficient. In this paper, a discrete Fourier transform is described and a fast Fourier transform algorithm is derived. An OFDM transceiver was simulated in the Matlab software package where QPSK and QAM modulation techniques were used

Regulation of ship's main engine lubrication oil temperature with Lyngo marine control system

U ovom završnom radu opisana je regulacija temperature ulja glavnog brodskog motora sustavom ‘Lyngso marine’. Prvi dio rada opisuje ideju povratne veze kao moćan alata današnjih industrijskih procesa pri regulaciji procesnih veličina kao što su tlak, temperature, protok itd..., te PID algoritam implementiran u današnja procesna računala. Drugi dio rada fokusira se na sam sustav ulja za podmazivanje glavnog brodskog motora te na dvama ključnim članovima za stabilnost regulacijske petlje uz sam regulatora, a to su izvršni član, u ovom slučaju troputni ventil te mjerni član. Zadnji dio rada posvećen je samoj regulaciji procesa unutar sustava ‘Lyngso marine’.This final paper describes PID control of ship’s main engine lube oil temperature in ‘Lyngso marine’ automation system. First part of the paper describes idea of a feedback as a powerful tool in todays’s industrial processes in regulation of process variables such as pressure, temperature, flow etc., along with PID algorithm implemented in todays’s process computers. Second part of the paper is focused on the lube oil systems itself, with actuator and sensor as two very important members of feedback loop together with controller. Final part of the paper describes process control in ‘Lyngso marine’ automation system

Regulation of ship's main engine lubrication oil temperature with Lyngo marine control system

U ovom završnom radu opisana je regulacija temperature ulja glavnog brodskog motora sustavom ‘Lyngso marine’. Prvi dio rada opisuje ideju povratne veze kao moćan alata današnjih industrijskih procesa pri regulaciji procesnih veličina kao što su tlak, temperature, protok itd..., te PID algoritam implementiran u današnja procesna računala. Drugi dio rada fokusira se na sam sustav ulja za podmazivanje glavnog brodskog motora te na dvama ključnim članovima za stabilnost regulacijske petlje uz sam regulatora, a to su izvršni član, u ovom slučaju troputni ventil te mjerni član. Zadnji dio rada posvećen je samoj regulaciji procesa unutar sustava ‘Lyngso marine’.This final paper describes PID control of ship’s main engine lube oil temperature in ‘Lyngso marine’ automation system. First part of the paper describes idea of a feedback as a powerful tool in todays’s industrial processes in regulation of process variables such as pressure, temperature, flow etc., along with PID algorithm implemented in todays’s process computers. Second part of the paper is focused on the lube oil systems itself, with actuator and sensor as two very important members of feedback loop together with controller. Final part of the paper describes process control in ‘Lyngso marine’ automation system

Regulation of ship's main engine lubrication oil temperature with Lyngo marine control system

U ovom završnom radu opisana je regulacija temperature ulja glavnog brodskog motora sustavom ‘Lyngso marine’. Prvi dio rada opisuje ideju povratne veze kao moćan alata današnjih industrijskih procesa pri regulaciji procesnih veličina kao što su tlak, temperature, protok itd..., te PID algoritam implementiran u današnja procesna računala. Drugi dio rada fokusira se na sam sustav ulja za podmazivanje glavnog brodskog motora te na dvama ključnim članovima za stabilnost regulacijske petlje uz sam regulatora, a to su izvršni član, u ovom slučaju troputni ventil te mjerni član. Zadnji dio rada posvećen je samoj regulaciji procesa unutar sustava ‘Lyngso marine’.This final paper describes PID control of ship’s main engine lube oil temperature in ‘Lyngso marine’ automation system. First part of the paper describes idea of a feedback as a powerful tool in todays’s industrial processes in regulation of process variables such as pressure, temperature, flow etc., along with PID algorithm implemented in todays’s process computers. Second part of the paper is focused on the lube oil systems itself, with actuator and sensor as two very important members of feedback loop together with controller. Final part of the paper describes process control in ‘Lyngso marine’ automation system

Application of discrete Fourier transform in information transmission by OFDM modulation

Frekvencijski multipleks ortogonalnih podnosilaca − OFDM predstavlja moćnu modulacijsku tehniku sposobnu za visoku brzinu prijenosa podataka u uvjetima vremenski disperzivnih bežičnih komunikacijskih kanala. Njegova robusnost na međusimbolnu i međukanalnu interferenciju ˇčini ga nezamjenjivim u modernim komunikacijskim sustavim. Korištenje brze Fourierove transformacije čini implementaciju OFDM sustava komputacijski jako efikasnom. U ovom radu opisana je diskretna Fourierova transformacija te je izveden algoritam brze Fourierove transformacije. U Matlab programskom paketu simuliran je OFDM primopredajnik gdje su se koristile QPSK i QAM modulacijske tehnike.Orthogonal frequency division multiplexing - OFDM is a powerful modulation technique capable of high speed data transmission in the conditions of time-dispersive wireless communication channels. Its robustness to intersymbol and interchannel interference makes it indispensable in modern communication systems. The use of fast Fourier transform makes the implementation of OFDM systems computationally very efficient. In this paper, a discrete Fourier transform is described and a fast Fourier transform algorithm is derived. An OFDM transceiver was simulated in the Matlab software package where QPSK and QAM modulation techniques were used

Sex Moderates the Effect of Aerobic Exercise on Some Aspects of Cognition in Cognitively Intact Younger and Middle-Age Adults

We recently reported the results of a randomized, parallel-group, observer-masked, community-based clinical trial of 132 cognitively normal individuals aged 20–67 with below median aerobic capacity who were randomly assigned to one of two 6-month, four-times-weekly conditions: aerobic exercise and stretching/toning. We now assessed potential sex moderation on exercise-related changes in aerobic capacity, BMI and cognitive function. There was no sex moderation of the effect of aerobic exercise on aerobic capacity or BMI. We had previously reported an effect of aerobic exercise on executive function that was moderated by age. We found additional moderation by sex, such that in any age range men improved more than women. Processing speed showed significant sex moderation but not significant age moderation. In men, processing speed significantly improved by week 12 (b = 0.35, p = 0.0051), but the effect was diminished relative to week 12 at week 24 (b = 0.24, p = 0.0578). In women, there was no exercise effect at either time point (week 12: b = −0.06, p = 0.4156; week 24: b = −0.11, p = 0.1841). Men benefited cognitively more than women from aerobic exercise. This study highlights the importance of using sex-disaggregated analyses when assessing the impact of physical exercise intervention, and the need to ascertain the underlying mechanisms for differential cognitive benefit by sex

The Effect of Three Months of Aerobic Training on Stroop Performance in Older Adults

Growing evidence supports the use of physical training interventions to improve both physical and cognitive performances in healthy older adults. Few studies have examined the impact of aerobic exercise on Stroop task performance, a measure of executive functions. In the current 3-month aerobic training study, 50 older adults (mean age = 67.96 ± 6.25 years) were randomly assigned to either a three-month physical training group or to a control group (waiting list). Training sessions were 3 times per week for 60 minutes. All participants completed pre- and post-test measures of cognitive performance using the modified Stroop task and physical performance (Rockport one-mile test). Compared to controls, the training group showed significant improvements in physical capacity (P<0.001) and enhanced Stroop performance, but only in the inhibition/switching condition (P<0.03). Furthermore, the increase in aerobic capacity induced by the training regimen correlated negatively with reaction time in the inhibition/switching condition of the Stroop task at posttest (r=−0.538; P=0.007). Importantly, the reported gains in cognitive performance were observed after only three months of physical training. Taken together, the results suggest that even short-term physical interventions can enhance older adults’ executive functions