Bismuth-coated mesoporous platinum microelectrodes as sensors for formic acid detection

Mesoporous platinum microeletrodes (MPtEs) modified by sub-monolayers of irreversibly adsorbed bismuth (Bi-MPtE) were investigated for their potential use as sensors for the detection of formic acid in direct formic acid fuel cells. The mesoporous platinum films were prepared by electrodeposition of platinum on Pt microdisks substrates 25 m diameter, from hexachloroplatinic acid dissolved in the aqueous domain of the lyotropic liquid crystalline phase of octaethylene glycol monohexadecyl ether. The roughness factor (RF) of the MPtEs was about two orders of magnitude greater than those of the corresponding polished microelectrodes. Bismuth ad-atoms onto the platinum surface were deposited by under potential deposition from 1 mM Bi3+ ions in 0.5 M H2SO4 solutions. The catalytic activity of a series of Bi-MPtEs, characterized by different roughness and fractional bismuth coverage (Bi), towards the oxidation of HCOOH, was investigated by cyclic voltammetry and potential step experiments. Compared to MPtEs, Bi-MPtEs displayed enhanced electrooxidation currents at lower potentials. The stability of irreversibly adsorbed bismuth, and consequently the Bi-MPtEs catalytic activity, was found to depend on the high potential limit employed in the measurements. In general, both electrode stability and electrocatalytic performance were good, provided that the operational potential was kept  0.4 V vs. Ag/AgCl. Bi-MPtEs with Bi > 0.3 provided almost sigmoidal shaped waves with low hysteresis, as those expected for microelectrodes working under steady state. The effect of concentration of HCOOH was investigated over the range 0.01 – 5 M, and linearity between current and concentration depended on both roughness factor and bismuth coverage. A Bi-MPtE characterised by RF = 210 and Bi ≥ 0.6 provided linearity up to 2 M of formic acid. Reproducibility of the sensors was within 2% (r.s.d). The same sensor, under the optimized experimental conditions, could be employed for at least two months with negligible loss of the initial performance

Changes in Fitness-Fatness Index following a Personalized, Community-Based Exercise Program in Physically Inactive Adults: a Randomised Controlled Trial

International Journal of Exercise Science 15(4): 1418-1429, 2022. Fitness-fatness index (FFI) is used to identify those at high risk of developing type 2 diabetes and cardiovascular events. It is measured as the ratio between an individual’s cardiorespiratory fitness (CRF) and waist-to-height ratio. Studies suggest that CRF and waist-to-height ratio are modifiable and can be improved by exercise. However, there is limited evidence surrounding a personalized approach to exercise prescription. This study investigated the impact of a 12-week personalized exercise program on FFI among sedentary individuals. It was hypothesized that the intervention would be effective in improving FFI in this cohort. One hundred and forty-two participants were randomized into two groups: i) personalised community-based intervention (n = 70); or ii) control (n = 72). Both groups underwent baseline anthropometric testing and a submaximal ‘talk-test’ to determine individual exercise intensities and baseline FFI. During the intervention, the control group underwent normal activities, whilst the treatment group received a 12-week personalised exercise program based on the American Council on Exercise (ACE) Integrated Fitness Training (IFT) guidelines. After 12-weeks, the treatment group demonstrated a significant increase in FFI (+13%), whilst the control group (-2%) showed a slight decrease (between-group difference, p = \u3c 0.001). Both CRF (+12%) and waist-to-height (-2%) also showed significant favourable changes in the treatment group, with no change in the control group (between group difference, p = 0.01). These findings indicate that a personalised approach to exercise prescription using the ACE IFT guidelines are beneficial in reducing FFI. Consequently, FFI could be implemented within standardized approaches to exercise to help reduce the risk of developing chronic conditions

Changes in the Second Ventilatory Threshold Following Individualised versus Standardised Exercise Prescription among Physically Inactive Adults: A Randomised Trial

The second ventilatory threshold (VT2) is established as an important indicator of exercise intensity tolerance. A higher VT2 allows for greater duration of higher intensity exercise participation and subsequently greater reductions in cardiovascular disease (CVD) risk. This study aimed to compare the efficacy of standardised and individualised exercise prescription on VT2 among physically inactive adults. Forty-nine physically inactive male and female participants (48.6 ± 11.5 years) were recruited and randomised into a 12-week standardised (n = 25) or individualised (n = 24) exercise prescription intervention. The exercise intensity for the standardised and individualised groups was prescribed as a percentage of heart rate reserve (HRR) or relative to the first ventilatory threshold (VT1) and VT2, respectively. Participants were required to complete a maximal graded exercise test at pre-and post-intervention to determine VT1 and VT2. Participants were categorised as responders to the intervention if an absolute VT2 change of at least 1.9% was attained. Thirty-eight participants were included in the analysis. A significant difference in VT2 change was found between individualised (pre vs. post: 70.6% vs. 78.7% maximum oxygen uptake (VO2max)) and standardised (pre vs. post: 72.5% vs. 72.3% VO2max) exercise groups. Individualised exercise prescription was significantly more efficacious (p = 0.04) in eliciting a positive response in VT2 (15/19, 79%) when compared to the standardised exercise group (9/19, 47%). Individualised exercise prescription appears to be more efficacious than standardised exercise prescription in eliciting a positive VT2 change among physically inactive adults. Increasing VT2 allows for greater tolerance to higher exercise intensities and therefore greater cardiovascular health outcomes

Can reducing sitting time in the university setting improve the cardiometabolic health of college students?

This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Purpose: The high prevalence of metabolic syndrome (MetS), prediabetes, and increased risk of cardiovascular diseases linked with prolonged sitting has created a need to identify options to limit sedentary behaviors. A potentially simple approach to achieve this goal in the university setting is to provide students the option to stand during courses rather than sit. The purpose of the present study was to examine the effects of standing in the college classroom setting on cardiometabolic risk factors in a cohort of college students. Patients and methods: Healthy college students (n=21) who attended at least two courses per week (a minimum of 5 hours) in a specified university building with standing desks participated in a 7-week intervention that was divided into three phases: 3 weeks of standing, 1 week of washout (sitting), and 3 weeks of sitting. The participants (mean ± SD: age, height, weight, body mass index, and waist-to-hip ratio were 22.7±6.4 years, 174.3±10.0 cm, 70.6±14.3 kg, 23.0±3.0 kg/m2, and 0.76±0.05, respectively) were randomly assigned to the phase of intervention of which they should start (sitting or standing), and all participants engaged in sitting during the washout phase. Cardiometabolic risk factors and metabolic equivalents (METs) were measured at baseline and weekly throughout the intervention. Results: Paired t-tests revealed significant differences (P<0.05) in all cardiometabolic risk factors between the 3 weeks of sitting and 3 weeks of standing time blocks. Moreover, MetS z-score was significantly improved (P<0.05) during the 3 weeks of standing (–5.91±2.70) vs 3 weeks of sitting (–5.25±2.69). The METs were significantly higher (P<0.05) during standing (1.47±0.09) than during sitting (1.02±0.07). Although there was considerable interindividual variability in the ∆ MetS z-score response, there was a 100% (21/21) incidence of a favorable change (ie, responders) in MetS z-score response. Conclusion: A standing desk in the classroom paradigm was found to significantly improve cardiometabolic health throughout a short 3 weeks time span. Increasing standing time in the classroom, and therefore lessening weekly sedentary behavior, could be a potential wide-scale, effective strategy for primordial prevention of cardiometabolic diseases

A retrospective evaluation of the Brain and Body Fitness Studio service on functional capacity and quality of life in people with neurological disorders

BackgroundPeople with neurological disorders (ND) are less physically active than the general population due to physical, sensory, and/or cognitive impairments. These individuals often feel intimidated to join mainstream health and wellness centers due to lack of specialized support for people with ND. The Brain and Body Fitness Studio (BBFS) is one of the first Accredited Exercise Physiologist-led interprofessional services in Adelaide South Australia to provide individualized evidence-based multimodal exercise prescription and social support for this population. This comprehensive retrospective study evaluated the impact of BBFS on functional capacity (FC) determined as the 6-min walk distance (6 MWD) achieved during a 6-min walk test (6 MWT), of its members with ND.MethodsSixty-two BBFS members (age, 66 ± 10 years; 60% male) with ND (85% Parkinson's Disease; average time since diagnosis, 4 years [IQR, 2 to 12 years]) and complete pre- and post-6-month clinical assessment of the primary outcome of the study, the 6 MWD, were included in this retrospective analysis. A series of sub-analyses were also performed to investigate the effects of adherence to the recommended prescription of at least twice a week in the program (≥80 vs. &lt; 80% adherence), and disease stage (time since diagnosis; ≥6 vs. &lt; 6 years) on FC.ResultsAlthough there was no statistically significant change in 6 MWD from pre- to post-6-month BBFS program (+15 ± 90 m, p = 0.19), a clinically meaningful improvement of &gt;14 m was evident. Improvement in 6 MWD was significantly greater in members who attended at least 80% of the recommended visits (≥80% visits, +37 ± 58 m; ≤ 80% visits,−1 ± 105 m, p = 0.046). We also found a 6 MWD improvement from pre- to post-6 months in those in the early years of their ND (&lt; 6 years since diagnosis, +39 ± 76 m), but not in those in the later years of their ND (≥6 years since diagnosis, −36 ± 123 m, between group difference, p = 0.029).ConclusionA clinically meaningful 6 MWD improvement may be elicited by services provided by BBFS in people with ND. Overall, the benefits appear to be more evident in members who attended the BBFS for at least 80% of the recommended visits and those who were in the early stage of their ND diagnosis

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum