| 1. |
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Hybrid Materials for Optical Limiting
- 2005
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Editorial proceedings (other academic/artistic)abstract
- Optical limiting materials based on alkynyl platinum derivatives and thiacalixarenes were produced using the sol-gel process. The molecular species were grafted to the matrix (class II hybrid) in order to maximise the concentration and the stability of the material. Broadband optical limiting performances in the visible wavelength region was observed in the prepared materials. Thermomechanical characterisation of the matrix will also be discussed.
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| 2. |
- Klingenberg, Lars, et al.
(author)
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Acute Sleep Restriction Reduces Insulin Sensitivity in Adolescent Boys
- 2013
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In: Sleep. - : Oxford University Press (OUP). - 0161-8105 .- 1550-9109. ; 36:7, s. 1085-1090
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Journal article (peer-reviewed)abstract
- Background: Short sleep duration has been linked to impaired glucose metabolism in many experimental studies. Moreover, studies have reported indications of an increased metabolic stress following sleep restriction. Objective: We aimed to investigate the effects of partial sleep deprivation on markers of glucose metabolism. Additionally, we aimed to investigate if short sleep duration induces a state of endocrine stress. Design: A randomized crossover design, with 2 experimental conditions: 3 consecutive nights of short sleep (SS, 4 h/night) and long sleep (LS, 9 h/night) duration. Subjects and Measurements: In 21 healthy, normal-weight male adolescents (mean +/- SD age: 16.8 +/- 1.3 y) we measured pre- and post-prandial glucose, insulin, C-peptide, and glucagon concentrations. Furthermore, we measured fasting cortisol, 24-h catecholamines, and sympathovagal balance. Results: Fasting insulin was 59% higher (P = 0.001) in the SS than the LS condition as was both fasting (24%, P < 0.001) and post-prandial (11%, P = 0.018) C-peptide. Pre- and post-prandial glucose and glucagon were unchanged between conditions. The homeostasis model assessment of insulin resistance (HOMA-IR) index was 65% higher (P = 0.002) and the Matsuda index was 28% lower (P = 0.007) in the SS condition compared to the LS condition. The awakening cortisol response and 24-h norepinephrine were not affected by sleep duration, whereas 24-h epinephrine was 24% lower (P = 0.013) in the SS condition. Neither daytime nor 24-h sympathovagal balance differed between sleep conditions. Short wave sleep was preserved in the SS condition. Conclusion: Short-term sleep restriction is associated with decreased insulin sensitivity in healthy normal-weight adolescent boys. There were no indications of endocrine stress beyond this.
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| 3. |
- Klingenberg, Lars, et al.
(author)
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Sleep restriction is not associated with a positive energy balance in adolescent boys
- 2012
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In: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 96:2, s. 240-248
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Journal article (peer-reviewed)abstract
- Background: A short sleep (SS) duration has been linked to obesity in observational studies. However, experimental evidence of the potential mechanisms of sleep restriction on energy balance is conflicting and, to our knowledge, nonexistent in adolescents.Objective: We investigated the effects of 3 consecutive nights of partial sleep deprivation on components of energy balance.Design: In a randomized, crossover design, 21 healthy, normal-weight male adolescents (mean +/- SD age: 16.8 +/- 1.3 y) completed the following 2 experimental conditions, each for 3 consecutive nights: an SS (4 h/night) and a long sleep (LS; 9 h/night) duration. Endpoints were 24-h energy expenditure (EE), spontaneous physical activity (SPA), postintervention diet-induced thermogenesis (DIT), appetite sensations, ad libitum energy intake (EI), and profiles of plasma ghrelin and leptin.Results: The 24-h EE on day 3 was 370 +/- 496 kJ higher in the SS condition than in the LS condition (P = 0.003). This difference in EE was explained by prolonged wakefulness in the SS condition and a 19% higher SPA (P = 0.003). In a postintervention breakfast-meal challenge, there was a 0.19-kJ/min smaller incremental AUC in DIT over 4 h in the SS condition than in the LS condition (P = 0.012) with no time X condition effect (P = 0.29). Subjects consumed 13% less energy in the ad libitum meal in the SS condition (P = 0.031), with a concomitant decreased motivation to eat. Concentrations of ghrelin and leptin remained unchanged with sleep restriction.Conclusion: Short-term sleep restriction in male adolescents is associated with a small negative energy balance driven by increased EE from prolonged wakefulness and a concomitant decreased El and motivation to eat. This trial was registered at clinicaltrials.gov as NCT01198431.
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| 4. |
- Torres-Lopez, Lucia V., et al.
(author)
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Effects of exercise on sleep in children with overweight/obesity: a randomized clinical trial
- 2023
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In: Obesity. - : WILEY. - 1930-7381 .- 1930-739X.
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Journal article (peer-reviewed)abstract
- ObjectiveThe objective of this study was to examine the chronic effects of a 20-week exercise training program on device-assessed sleep and sleep-disordered breathing; and to determine whether participating in a session of the exercise program had effects on device-assessed sleep the subsequent night in children with overweight/obesity.MethodsA randomized clinical trial was conducted from November 2014 to June 2016. A total of 109 children (age 8-11 years) with overweight/obesity were randomized into an exercise training or control group. The exercise program included aerobic and resistance training 3 to 5 days/week. The control group participants continued their usual lifestyle. Device-assessed sleep outcomes were measured using wrist-worn actigraphy at baseline, in the middle of the exercise program (10th week), and at postintervention for seven consecutive days (24 h/day), and sleep-disordered breathing was measured via the Pediatric Sleep Questionnaire.ResultsThe exercise training program had a statistically significant effect on wake after sleep onset time (-10.8 min/day, -0.5 SDs, p = 0.040). No other chronic or acute effects (i.e., the subsequent night of attending a session of the exercise training program) were observed on the remaining sleep outcomes.ConclusionsA 20-week exercise training program reduced wake after sleep onset time in children with overweight/obesity. Future randomized trials that include a sample of children with poor sleep health at baseline are needed to better appreciate the role of exercise in sleep health.
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| 5. |
- Tremblay, Mark S, et al.
(author)
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Sedentary Behavior Research Network (SBRN) - Terminology Consensus Project process and outcome.
- 2017
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In: The international journal of behavioral nutrition and physical activity. - : Springer Science and Business Media LLC. - 1479-5868. ; 14:1
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Journal article (peer-reviewed)abstract
- The prominence of sedentary behavior research in health science has grown rapidly. With this growth there is increasing urgency for clear, common and accepted terminology and definitions. Such standardization is difficult to achieve, especially across multi-disciplinary researchers, practitioners, and industries. The Sedentary Behavior Research Network (SBRN) undertook a Terminology Consensus Project to address this need.First, a literature review was completed to identify key terms in sedentary behavior research. These key terms were then reviewed and modified by a Steering Committee formed by SBRN. Next, SBRN members were invited to contribute to this project and interested participants reviewed and provided feedback on the proposed list of terms and draft definitions through an online survey. Finally, a conceptual model and consensus definitions (including caveats and examples for all age groups and functional abilities) were finalized based on the feedback received from the 87 SBRN member participants who responded to the original invitation and survey.Consensus definitions for the terms physical inactivity, stationary behavior, sedentary behavior, standing, screen time, non-screen-based sedentary time, sitting, reclining, lying, sedentary behavior pattern, as well as how the terms bouts, breaks, and interruptions should be used in this context are provided.It is hoped that the definitions resulting from this comprehensive, transparent, and broad-based participatory process will result in standardized terminology that is widely supported and adopted, thereby advancing future research, interventions, policies, and practices related to sedentary behaviors.
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