Self-Selected Pacing Strategy and Lactate Response in Individual Medley Time Trials

The 200 and 400-yard individual medley (IM; 200 IM and 400 IM, respectively) are two swimming events that challenge swimmers\u27 versatility. Each of these events has different physiological requirements, where the 200 IM is viewed as an anaerobic event and the 400 IM as an aerobic event. Additionally, the IMs require performance in all four competitive stroke disciplines in a specific order (butterfly, backstroke, breaststroke, and freestyle), with each stroke requiring a different magnitude of intensity, efficiency, and speed. Purpose: To study the different pacing strategies and corresponding blood lactate response during the 200 IM and 400 IM in National Collegiate Athletic Association (NCAA) Division III swimmers. Methods: 10 NCAA Division III swimmers (age: 19.7 ± 0.95yrs, height: 169.0 ± 6.4cm, weight: 71.8 ± 0.95kg) performed a simulated time trials of the 200 IM and 400 IM during the competitive season. Blood lactate (BLA) was measured prior to warm up, prior to racing, and at the completion of the time trial. Change in blood lactate (ΔBLA) was calculated from the pre and post BLA. Splits were taken for each lap (50 yard) of each stroke, and segment (50,100 yard) velocities were calculated. Additionally, percents of the total time each stroke took were also calculated. Multiple repeated measures ANOVAs were used to determine significant differences. Results: No significant differences (p\u3e0.05) were reported between the BLA Post 200 IM (8.9±3.2 mmol/L) and BLA Post 400 IM (8.87±2.4 mmol/L), nor in ΔBLA2IM (7.56±3.25 mmol/L) and ΔBLA4IM (6.11±2.82 mmol/L). Rate of perceived exertion (RPE) was found to be significantly (p\u3c0.01) greater following the 400 IM (9.1±0.88) versus the 200 IM (7.4±0.84). Significant interactions were found (p\u3c0.05) between the stroke velocities and stroke percentage of total time for the 200 IM and 400 IM. Conclusion: Measurement of BLA showed that there was an equivalent amount of anaerobic involvement between the 200 IM and 400 IM but the pacing strategies were different

Does parent stress predict the quality of life of children with a diagnosis of ADHD?:A comparison of parent and child perspectives

Objective: There are indicators that parental psychological factors may affect how parents evaluate their child’s quality of life (QoL) when the child has a health condition. This study examined the impact of parents’ perceived stress on parent and child ratings of the QoL of children with ADHD. Method: A cross-sectional sample of 45 matched parent–child dyads completed parallel versions of the KIDSCREEN-27. Children were 8 to 14 years with clinician diagnosed ADHD. Results: Parents who rated their child’s QoL lower than their child had higher perceived stress scores. Parent stress was a unique predictor of child QoL from parent proxy-rated but not child-rated QoL scores. Conclusion: Parents’ perceived stress may play an important role in their assessments of their child’s QoL, suggesting both parent and child perspectives of QoL should be utilized wherever possible. Interventions that target parent stress may contribute to improvements in the child’s QoL. </jats:p

Procurement from local producers for food service in primary and secondary school settings: A scoping review

Issue addressed: Australian school canteen guidelines do not broadly incentivise procuring food from local producers, despite evidence of this occurring abroad. This scoping review aims to investigate what is known about local food procurement for school foodservice. Methods: A scoping review of peer-reviewed articles published since 2000 was undertaken using MEDLINE, CINAHL and Scopus. Results: Twenty-one studies met the inclusion criteria. Local food was generally perceived as fresher and more nutritious. Small, positive impacts on fruit and vegetable intake have been demonstrated when food is procured locally. Challenges identified included concerns around food safety, varied availability, time spent coordinating food supply, lack of incentive from regional or national guidelines, inadequate kitchen facilities and budget constraints. Conclusions: There is no universal definition or standard for procuring ‘local food’. The main motivation for local food procurement was a sense of social responsibility, however there are barriers, including cost, facilities and food safety. Purchasing food locally holds potential to benefit the local economy but government funding and policy supporting local and small-scale producers is an important enabler. So what?: Government support to build stakeholder capacity is important in establishing and maintaining these programmes and would be crucial in achieving change in Australian schools. Investigating feasibility of a national school lunch service would be beneficial, as these programmes may have merit not just in feeding children but also in supporting the local economy. Further research is warranted in this area

Establishing viable fault management strategies for distributed electrical propulsion aircraft

Electrical propulsion has the potential to increase aircraft performance. However, this will require the design and development of an appropriate aircraft electrical system to power the propulsor motors. In order to protect this system against electrical faults, which have the potential to threaten the safety of the aircraft, a robust fault management strategy (FMS) is required. The FMS will comprise aspects of system design such as redundancy, reliability and reconfiguration and will rely on a range of protection devices deployed on the electrical system to intercept and manage faults. The electrical architecture will be shaped by the FMS as this will determine the optimal configuration to enable security of supply. The protection system is integral to the system design. Hence it must to be considered from the outset, as part of the wider aircraft concept development. This paper presents a robust framework to develop the optimal FMS for an electrical propulsion aircraft, which is subject to all the relevant aircraft constraints and incorporates the available protection devices for a chosen aircraft for a given developmental timeframe. A case study is then presented in which this protection design methodology is applied to the NASA STARC-ABL aircraft concept in order to demonstrate that the available protection for an electrical propulsion aircraft defines the possible electrical architectures

Impact of key design constraints on fault management strategies for distributed electrical propulsion aircraft

Electrically driven distributed propulsion has been presented as a possible solution to reduce aircraft noise and emissions, despite increasing global levels of air travel. In order to realise electrical propulsion, novel aircraft electrical systems are required. Since the electrical system must maintain security of power supply to the motors during flight, the protection devices employed on an electrical propulsion aircraft will form a crucial part of system design. However, electrical protection for complex aircraft electrical systems poses a number of challenges, particularly with regard to the weight, volume and efficiency constraints specific to aerospace applications. Furthermore, electrical systems will need to operate at higher power levels and incorporate new technologies, many of which are unproven at altitude and in the harsh aircraft environment. Therefore, today’s commercially available aerospace protection technologies are likely to require significant development before they can be considered as part of a fault management strategy for a next generation aircraft. By mapping the protection device trade space based on published literature to date, the discrepancy between the current status of protection devices and the target specifications can be identified for a given time frame. This paper will describe a process of electrical network design that is driven by the protection system requirements, incorporates key technology constraints and analyses the protection device trade space to derive feasible fault management strategies

The efficacy of different vitamin D supplementation delivery methods on serum 25(OH)D: A randomised double-blind placebo trial

Background: The use of vitamin D supplementation has increased due to greater recognition of widespread deficiency. Aims: There has been little research on the effectiveness of different delivery methods and therefore the aim of was to test the efficacy of different delivery methods on serum 25(OH)D. Methods: Using a randomised repeated measures double-blind placebo design (registered under ClinicalTrials.gov Identifier no. NCT03463642), changes in serum 25(OH)D over a 4-week period using a capillary spot method were monitored. 62 female participants blindly chose a number related to a supplementation delivery method: pill placebo, pill, oral liquid, oral liquid placebo, Skin oil application (SOA) placebo, SOA plus vitamin D3 suspension, or SOA plus vitamin D3 suspension with essential oil enhancer; active vitamin D supplements contained 100,000IU. Participants took their allocated supplements over a 24-hr period with serum 25(OH)D retested 4 weeks later. Liquid chromatography-tandem mass spectrometry method was applied to dried blood spot samples by an independent laboratory. Results: ANCOVA reported a significant difference between the groups (F1,6 = 146.68; p &lt; 0.001, eta2 = 0.51). Separate analysis within the delivery methods (pill, SOA, oral liquid) indicated significant differences between the active and placebo supplementation groups (p &lt; 0.01). Post hoc analysis of absolute changes indicated vit D pill and SOA + vit D + essential oil had significant increases (p &lt; 0.05) in serum 25(OH)D compared to all other interventions with no significant difference between them. Conclusions: In human participants vitamin D oral pill has the greatest effect on serum 25(OH)D levels. Skin oil application delivery of vitamin D using a penetrator enhancer has also been shown to be an effective method of delivery. © 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolis

Recollections of pressure to eat during childhood, but not picky eating, predict young adult eating behavior

Picky eating is a childhood behavior that vexes many parents and is a symptom in the newer diagnosis of Avoidant/Restrictive Food Intake Disorder (ARFID) in adults. Pressure to eat, a parental controlling feeding practice aimed at encouraging a child to eat more, is associated with picky eating and a number of other childhood eating concerns. Low intuitive eating, an insensitivity to internal hunger and satiety cues, is also associated with a number of problem eating behaviors in adulthood. Whether picky eating and pressure to eat are predictive of young adult eating behavior is relatively unstudied. Current adult intuitive eating and disordered eating behaviors were self-reported by 170 college students, along with childhood picky eating and pressure through retrospective self- and parent reports. Hierarchical regression analyses revealed that childhood parental pressure to eat, but not picky eating, predicted intuitive eating and disordered eating symptoms in college students. These findings suggest that parental pressure in childhood is associated with problematic eating patterns in young adulthood. Additional research is needed to understand the extent to which parental pressure is a reaction to or perhaps compounds the development of problematic eating behavior

Does child weight influence how mothers report their feeding practices?

Objectives. The present study aimed to ascertain whether parental reports of their feeding practices are associated with independent observations of these behaviours, and whether the reliability of maternal report depends upon the child's weight. Methods. A total of 56 mothers and their children ate a lunch to satiety which was videotaped and coded for maternal use of control during feeding. Mothers also completed questionnaires about their feeding practices and children were weighed and measured. Results. Maternal reports of controlling feeding practices were poorly related to independent observations of these behaviours in the laboratory. However, there was a significant interaction between child BMI z score and observed pressure to eat in predicting maternally reported pressure to eat. There was also a significant interaction between child BMI z score and observed maternal restriction with food in predicting maternally reported restriction. When decomposed, these interactions suggested that only mothers of relatively underweight children were accurate at reporting their use of pressure to eat when compared to independent observations. For mothers of relatively overweight children there was a significant negative relationship between observed and reported restriction over food. Conclusions. Overall there was poor correspondence between maternal reports and independent observations of the use of controlling feeding practices. Further research is needed to replicate these findings and to ascertain whether parents who are inaccurate at reporting their use of these feeding practices are unaware that they are using controlling feeding practices or whether they are responding in socially desirable ways to questionnaires assessing their feeding behaviour. © 2011 Informa Healthcare

Volcanic controls on the microbial habitability of Mars‐analogue hydrothermal environments

Due to their potential to support chemolithotrophic life, relic hydrothermal systems on Mars are a key target for astrobiological exploration. We analysed water and sediments at six geothermal pools from the rhyolitic Kerlingarfjöll and basaltic Kverkfjöll volcanoes in Iceland, to investigate the localised controls on the habitability of these systems in terms of microbial community function. Our results show that host lithology plays a minor role in pool geochemistry and authigenic mineralogy, with the system geochemistry primarily controlled by deep volcanic processes. We find that by dictating pool water pH and redox conditions, deep volcanic processes are the primary control on microbial community structure and function, with water input from the proximal glacier acting as a secondary control by regulating pool temperatures. Kerlingarfjöll pools have reduced, circum-neutral CO2-rich waters with authigenic calcite-, pyrite- and kaolinite-bearing sediments. The dominant metabolisms inferred from community profiles obtained by 16S rRNA gene sequencing are methanogenesis, respiration of sulphate and sulphur (S0) oxidation. In contrast, Kverkfjöll pools have oxidised, acidic (pH 42- and high argillic alteration, resulting in Al-phyllosilicate-rich sediments. The prevailing metabolisms here are iron oxidation, sulphur oxidation and nitrification. Where analogous ice-fed hydrothermal systems existed on early Mars, similar volcanic processes would likely have controlled localised metabolic potential and thus habitability. Moreover, such systems offer several habitability advantages, including a localised source of metabolic redox pairs for chemolithotrophic microorganisms and accessible trace metals. Similar pools could have provided transient environments for life on Mars; when paired with surface or near-surface ice, these habitability niches could have persisted into the Amazonian. Additionally, they offer a confined site for biosignature formation and deposition that lends itself well to in situ robotic exploration