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Background: Peripartum antibiotics are commonly administered. Little is known of the attitudes of pregnant women toward peripartum antibiotics. Aim: We aimed to assess the awareness of and attitudes toward peripartum antibiotic use in Australian women. Materials and Methods: We surveyed post‐partum women at three hospitals over six months. Women reported if they received antibiotics 48 h either side of delivery and responded to statements assessing attitudes to peripartum antibiotic use. Administered antibiotics were recorded. We reported the proportion receiving antibiotics and the proportion aware of receiving them. Participants responded on five‐point Likert scales and selected side effects of concern. Results: Participants responding were 248 of 299 (83%, Royal Brisbane and Women's Hospital), 56 of 106 (53%, Caboolture Hospital) and 17 (Redcliffe Hospital, denominator not recorded). Of 183 (57%) receiving antibiotics, 134 (73%) received them pre‐delivery only, 18 (10%) post‐delivery only and 31 (17%) pre‐ and post‐delivery. Pre‐delivery, the most common indication was pre‐incisional prophylaxis for caesarean delivery (93 of 160 responses, 58%). Seventy‐nine (51%, 156 responses) of those receiving pre‐delivery antibiotics were aware. Of 49 women receiving post‐delivery antibiotics, 36 (73%) were aware. Most agreed they were worried that pre‐delivery antibiotics would affect their baby (198, 62%) and 160 (50%) were concerned about effects on their own microbiome. Most (204, 65%) agreed they would rather not take antibiotics while breastfeeding. Conclusion: Many women were unaware of receiving pre‐delivery antibiotics. Most had concerns about side effects. Improved communication regarding peripartum antibiotic use would improve patient‐centred care. [ABSTRACT FROM AUTHOR]

Aim: Dietary nitrate (NO3−) supplementation increases nitric oxide bioavailability and can enhance exercise performance. We investigated the distribution and metabolic fate of ingested NO3− at rest and during exercise with a focus on skeletal muscle. Methods: In a randomized, crossover study, 10 healthy volunteers consumed 12.8 mmol 15N‐labeled potassium nitrate (K15NO3; NIT) or potassium chloride placebo (PLA). Muscle biopsies were taken at baseline, at 1‐ and 3‐h post‐supplement ingestion, and immediately following the completion of 60 maximal intermittent contractions of the knee extensors. Muscle, plasma, saliva, and urine samples were analyzed using chemiluminescence to determine absolute [NO3−] and [NO2−], and by mass spectrometry to determine the proportion of NO3− and NO2− that was 15N‐labeled. Results: Neither muscle [NO3−] nor [NO2−] were altered by PLA. Following NIT, muscle [NO3−] (but not [NO2−]) was elevated at 1‐h (from ~35 to 147 nmol/g, p < 0.001) and 3‐h, with almost all of the increase being 15N‐labeled. There was a significant reduction in 15N‐labeled muscle [NO3−] from pre‐ to post‐exercise. Relative to PLA, mean muscle torque production was ~7% greater during the first 18 contractions following NIT. This improvement in torque was correlated with the pre‐exercise 15N‐labeled muscle [NO3−] and the magnitude of decline in 15N‐labeled muscle [NO3−] during exercise (r = 0.66 and r = 0.62, respectively; p < 0.01). Conclusion: This study shows, for the first time, that skeletal muscle rapidly takes up dietary NO3−, the elevated muscle [NO3−] following NO3− ingestion declines during exercise, and muscle NO3− dynamics are associated with enhanced torque production during maximal intermittent muscle contractions. [ABSTRACT FROM AUTHOR]

Key points: Nitric oxide (NO), a potent vasodilator and a regulator of many physiological processes, is produced in mammals both enzymatically and by reduction of nitrite and nitrate ions.We have previously reported that, in rodents, skeletal muscle serves as a nitrate reservoir, with nitrate levels greatly exceeding those in blood or other internal organs, and with nitrate being reduced to NO during exercise.In the current study, we show that nitrate concentration is substantially greater in skeletal muscle than in blood and is elevated further by dietary nitrate ingestion in human volunteers. We also show that high‐intensity exercise results in a reduction in the skeletal muscle nitrate store following supplementation, likely as a consequence of its reduction to nitrite and NO.We also report the presence of sialin, a nitrate transporter, and xanthine oxidoreductase in human skeletal muscle, indicating that muscle has the necessary apparatus for nitrate transport, storage and metabolism. Rodent skeletal muscle contains a large store of nitrate that can be augmented by the consumption of dietary nitrate. This muscle nitrate reservoir has been found to be an important source of nitrite and nitric oxide (NO) via its reduction by tissue xanthine oxidoreductase. To explore if this pathway is also active in human skeletal muscle during exercise, and if it is sensitive to local nitrate availability, we assessed exercise‐induced changes in muscle nitrate and nitrite concentrations in young healthy humans, under baseline conditions and following dietary nitrate consumption. We found that baseline nitrate and nitrite concentrations were far higher in muscle than in plasma (∼4‐fold and ∼29‐fold, respectively), and that the consumption of a single bolus of dietary nitrate (12.8 mmol) significantly elevated nitrate concentration in both plasma (∼19‐fold) and muscle (∼5‐fold). Consistent with these observations, and with previous suggestions of active muscle nitrate transport, we present western blot data to show significant expression of the active nitrate/nitrite transporter sialin in human skeletal muscle. Furthermore, we report an exercise‐induced reduction in human muscle nitrate concentration (by ∼39%), but only in the presence of an increased muscle nitrate store. Our results indicate that human skeletal muscle nitrate stores are sensitive to dietary nitrate intake and may contribute to NO generation during exercise. Together, these findings suggest that skeletal muscle plays an important role in the transport, storage and metabolism of nitrate in humans. Key points: Nitric oxide (NO), a potent vasodilator and a regulator of many physiological processes, is produced in mammals both enzymatically and by reduction of nitrite and nitrate ions.We have previously reported that, in rodents, skeletal muscle serves as a nitrate reservoir, with nitrate levels greatly exceeding those in blood or other internal organs, and with nitrate being reduced to NO during exercise.In the current study, we show that nitrate concentration is substantially greater in skeletal muscle than in blood and is elevated further by dietary nitrate ingestion in human volunteers. We also show that high‐intensity exercise results in a reduction in the skeletal muscle nitrate store following supplementation, likely as a consequence of its reduction to nitrite and NO.We also report the presence of sialin, a nitrate transporter, and xanthine oxidoreductase in human skeletal muscle, indicating that muscle has the necessary apparatus for nitrate transport, storage and metabolism. [ABSTRACT FROM AUTHOR]

Key points The power-asymptote (critical power; CP) of the hyperbolic power-time relationship for high-intensity exercise defines a threshold between steady-state and non-steady-state exercise intensities and the curvature constant ( W′) indicates a fixed capacity for work >CP that is related to a loss of muscular efficiency., The present study reports novel evidence on the muscle metabolic underpinnings of CP and W′ during whole-body exercise and their relationships to muscle fibre type., We show that the W′ is not correlated with muscle fibre type distribution and that it represents an elevated energy contribution from both oxidative and glycolytic/glycogenolytic metabolism., We show that there is a positive correlation between CP and highly oxidative type I muscle fibres and that muscle metabolic steady-state is attainable CP., Our findings indicate a mechanistic link between the bioenergetic characteristics of muscle fibre types and the power-time relationship for high-intensity exercise., Abstract We hypothesized that: (1) the critical power (CP) will represent a boundary separating steady-state from non-steady-state muscle metabolic responses during whole-body exercise and (2) that the CP and the curvature constant ( W′) of the power-time relationship for high-intensity exercise will be correlated with type I and type IIx muscle fibre distributions, respectively. Four men and four women performed a 3 min all-out cycling test for the estimation of CP and constant work rate (CWR) tests slightly >CP until exhaustion ( Tlim), slightly CP Tlim isotime to test the first hypothesis. Eleven men performed 3 min all-out tests and donated muscle biopsies to test the second hypothesis. Below CP, muscle [PCr] [42.6 ± 7.1 vs. 49.4 ± 6.9 mmol (kg d.w.)−1], [La−] [34.8 ± 12.6 vs. 35.5 ± 13.2 mmol (kg d.w.)−1] and pH (7.11 ± 0.08 vs. 7.10 ± 0.11) remained stable between ∼12 and 24 min ( P > 0.05 for all), whereas these variables changed with time >CP such that they were greater [[La−] 95.6 ± 14.1 mmol (kg d.w.)−1] and lower [[PCr] 24.2 ± 3.9 mmol (kg d.w.)−1; pH 6.84 ± 0.06] ( P < 0.05) at Tlim (740 ± 186 s) than during the

Background: Machine learning (ML) provides novel opportunities for human behavior research and clinical translation, yet its application can have noted pitfalls (Bone et al., 2015). In this work, we fastidiously utilize ML to derive autism spectrum disorder (ASD) instrument algorithms in an attempt to improve upon widely used ASD screening and diagnostic tools. Methods: The data consisted of Autism Diagnostic Interview-Revised (ADI-R) and Social Responsiveness Scale (SRS) scores for 1,264 verbal individuals with ASD and 462 verbal individuals with non- ASD developmental or psychiatric disorders, split at age 10. Algorithms were created via a robust ML classifier, support vector machine, while targeting best-estimate clinical diagnosis of ASD versus non-ASD. Parameter settings were tuned in multiple levels of cross-validation. Results: The created algorithms were more effective (higher performing) than the current algorithms, were tunable (sensitivity and specificity can be differentially weighted), and were more efficient (achieving near-peak performance with five or fewer codes). Results from ML-based fusion of ADIR and SRS are reported. We present a screener algorithm for below (above) age 10 that reached 89.2% (86.7%) sensitivity and 59.0% (53.4%) specificity with only five behavioral codes. Conclusions: ML is useful for creating robust, customizable instrument algorithms. In a unique dataset comprised of controls with other difficulties, our findings highlight the limitations of current caregiver-report instruments and indicate possible avenues for improving ASD screening and diagnostic tools. [ABSTRACT FROM AUTHOR]

It has been shown that the critical power (CP) in cycling estimated using a novel 3-min all-out protocol is reliable and closely matches the CP derived from conventional procedures. The purpose of this study was to assess the predictive validity of the all-out test CP estimate. We hypothesised that the all-out test CP would be significantly correlated with 16.1-km road time-trial (TT) performance and more strongly correlated with performance than the gas exchange threshold (GET), respiratory compensation point (RCP) andV̇O2max. Ten club-level male cyclists (mean±SD: age 33.8±8.2 y, body mass 73.8±4.3 kg,V̇O2max 60±4 ml·kg−1·min−1) performed a 10-mile road TT, a ramp incremental test to exhaustion, and two 3-min all-out tests, the first of which served as familiarisation. The 16.1-km TT performance (27.1±1.2 min) was significantly correlated with the CP (309±34 W;r=−0.83,P<0.01) and total work done during the all-out test (70.9±6.5 kJ;r=−0.86,P<0.01), the ramp incremental test peak power (433±30 W;r=−0.75,P<0.05) and the RCP (315±29 W;r=−0.68,P<0.05), but not with GET (151±32 W;r=−0.21) or theV̇O2max (4.41±0.25 L·min−1;r=−0.60). These data provide evidence for the predictive validity and practical performance relevance of the 3-min all-out test. The 3-min all-out test CP may represent a useful addition to the battery of tests employed by applied sport physiologists or coaches to track fitness and predict performance in atheletes. [ABSTRACT FROM PUBLISHER]

Offers a reply to a comment by Glenn Gotz on the article `The Dynamics of Job Separation: The Case of Federal Employees.' Advantages of a dynamic programming model under uncertainty relative to the article's model; Clarifications on the difference between the two models in behavioural assumptions and in computational difficulty; Optimal stopping model of the type discussed by Gotz.

Presents a study that developed a multiperiod quit probability model to examine the dynamics of job separation among civilian workers in the United States federal government. Estimated effects of relative federal government wages and other variables on quits; Policy and theoretical objective of the analysis; Utilization of maximum-likelihood techniques.

A thermal process has been developed to create 3D cover glass for mobile device applications. After forming, the glass is ion-exchanged to make a strong, damage-resistant structure. The response of this glass to stress and damage events is equivalent to that of 2D Corning® Gorilla® Glass. [ABSTRACT FROM AUTHOR]

The maximal lactate steady state (MLSS) and the critical power (CP) are two widely used indices of the highest oxidative metabolic rate that can be sustained during continuous exercise and are often considered to be synonymous. However, while perhaps having similarities in principle, methodological differences in the assessment of these parameters typically result in MLSS occurring at a somewhat lower power output or running speed and exercise at CP being sustainable for no more than approximately 20–30 min. This has led to the view that CP overestimates the 'actual' maximal metabolic steady state and that MLSS should be considered the 'gold standard' metric for the evaluation of endurance exercise capacity. In this article we will present evidence consistent with the contrary conclusion: i.e., that (1) as presently defined, MLSS naturally underestimates the actual maximal metabolic steady state; and (2) CP alone represents the boundary between discrete exercise intensity domains within which the dynamic cardiorespiratory and muscle metabolic responses to exercise differ profoundly. While both MLSS and CP may have relevance for athletic training and performance, we urge that the distinction between the two concepts/metrics be better appreciated and that comparisons between MLSS and CP, undertaken in the mistaken belief that they are theoretically synonymous, is discontinued. CP represents the genuine boundary separating exercise in which physiological homeostasis can be maintained from exercise in which it cannot, and should be considered the gold standard when the goal is to determine the maximal metabolic steady state. [ABSTRACT FROM AUTHOR]

Aim: Dietary nitrate (NO 3 - ) supplementation increases nitric oxide bioavailability and can enhance exercise performance. We investigated the distribution and metabolic fate of ingested NO 3 - at rest and during exercise with a focus on skeletal muscle., Methods: In a randomized, crossover study, 10 healthy volunteers consumed 12.8 mmol 15 N-labeled potassium nitrate (K 15 NO 3 ; NIT) or potassium chloride placebo (PLA). Muscle biopsies were taken at baseline, at 1- and 3-h post-supplement ingestion, and immediately following the completion of 60 maximal intermittent contractions of the knee extensors. Muscle, plasma, saliva, and urine samples were analyzed using chemiluminescence to determine absolute [NO 3 - ] and [NO 2 - ], and by mass spectrometry to determine the proportion of NO 3 - and NO 2 - that was 15 N-labeled., Results: Neither muscle [NO 3 - ] nor [NO 2 - ] were altered by PLA. Following NIT, muscle [NO 3 - ] (but not [NO 2 - ]) was elevated at 1-h (from ~35 to 147 nmol/g, p < 0.001) and 3-h, with almost all of the increase being 15 N-labeled. There was a significant reduction in 15 N-labeled muscle [NO 3 - ] from pre- to post-exercise. Relative to PLA, mean muscle torque production was ~7% greater during the first 18 contractions following NIT. This improvement in torque was correlated with the pre-exercise 15 N-labeled muscle [NO 3 - ] and the magnitude of decline in 15 N-labeled muscle [NO 3 - ] during exercise (r = 0.66 and r = 0.62, respectively; p < 0.01)., Conclusion: This study shows, for the first time, that skeletal muscle rapidly takes up dietary NO 3 - , the elevated muscle [NO 3 - ] following NO 3 - ingestion declines during exercise, and muscle NO 3 - dynamics are associated with enhanced torque production during maximal intermittent muscle contractions., (© 2023 The Authors. Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.)

Background: Peripartum antibiotics are commonly administered. Little is known of the attitudes of pregnant women toward peripartum antibiotics., Aim: We aimed to assess the awareness of and attitudes toward peripartum antibiotic use in Australian women., Materials and Methods: We surveyed post-partum women at three hospitals over six months. Women reported if they received antibiotics 48 h either side of delivery and responded to statements assessing attitudes to peripartum antibiotic use. Administered antibiotics were recorded. We reported the proportion receiving antibiotics and the proportion aware of receiving them. Participants responded on five-point Likert scales and selected side effects of concern., Results: Participants responding were 248 of 299 (83%, Royal Brisbane and Women's Hospital), 56 of 106 (53%, Caboolture Hospital) and 17 (Redcliffe Hospital, denominator not recorded). Of 183 (57%) receiving antibiotics, 134 (73%) received them pre-delivery only, 18 (10%) post-delivery only and 31 (17%) pre- and post-delivery. Pre-delivery, the most common indication was pre-incisional prophylaxis for caesarean delivery (93 of 160 responses, 58%). Seventy-nine (51%, 156 responses) of those receiving pre-delivery antibiotics were aware. Of 49 women receiving post-delivery antibiotics, 36 (73%) were aware. Most agreed they were worried that pre-delivery antibiotics would affect their baby (198, 62%) and 160 (50%) were concerned about effects on their own microbiome. Most (204, 65%) agreed they would rather not take antibiotics while breastfeeding., Conclusion: Many women were unaware of receiving pre-delivery antibiotics. Most had concerns about side effects. Improved communication regarding peripartum antibiotic use would improve patient-centred care., (© 2022 The Authors. Australian and New Zealand Journal of Obstetrics and Gynaecology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Obstetricians and Gynaecologists.)