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The heel pad (HP) which is located below the calcaneus comprises a composition of morphometrical and morphological arrangements of soft tissues that are influenced by factors such as gender, age and obesity. It is well known that HP pain and Achilles tendonitis consist of discomfort, pain and swelling symptoms that usually develop from excessive physical activities such as walking, jumping and running. The purpose of this study was to develop biomechanical techniques to evaluate the function and characteristics of the HP. Ten healthy participants (five males and five females) participated in this laboratory-based study, each performing a two-footed heel raise to mimic the toe-off phase during human locomotion. Twenty-six (3 mm) retroreflective markers were attached to the left and right heels (thirteen markers on each heel). Kinematic data was captured using three-dimensional motion analysis cameras synchronised with force plates. Descriptive and multivariate statistical tests were used in this study. In addition, a biomechanical technique that utilises only six markers from 26 markers to assess HP deformation and function has been developed and used in this study. Overall HP displacement was significantly higher in males on the most lateral part of the right heel (p< 0.05). No significant differences were evident when comparing the non-dominant and dominant heels during the baseline, unloading and loading phases (p> 0.05). Findings from this study suggested that biomechanical outputs expressed as derivatives from tracked HP marker movements can morphologically and morphometrically characterise HP soft tissue deformation changes. The outcome of this study highlights the importance of 3D motion analysis being used as a potential prospective intervention to quantify the function / characteristics of the heel pad soft tissues.

This study has produced an improved percentile and seasonal (median) trend estimate of free tropospheric ozone above western North America (WNA), through a data fusion of ozonesonde, lidar, commercial aircraft, and field campaign measurements. Our method combines heterogeneous data sets according to the consensus data characteristics and inherent uncertainty in order to produce our best fused product. In response to different data collection environments (in situ or ground‐based), we investigate the ozone variability based on a wide range of percentiles, which is preferable for trend detection due to tropospheric ozone's high degree of heteroscedasticity (i.e., inconsistent trends and variability between different ozone percentiles). We then compare the ozone trends and variability above the California sub‐domain to the full WNA region for better understanding of the correlations between different regional scales. In California, the 1995–2021 percentile (from the 5th to 95th) and seasonal trends are clearly positive in terms of high signal‐to‐noise ratios. The magnitude of the trends is generally weaker over WNA compared to California, but reliable positive trends can still be found between the 10th and 70th percentiles, as well as winter and summer, whereas autumn shows a negative trend over the same period. In addition, dozens of rural surface sites across the region are selected to represent the boundary layer variability. In contrast to increasing free tropospheric ozone, we find overall strong negative surface trends since 1995, with the greatest divergence found in summer. Throughout the analysis implications of the COVID‐19 economic downturn on ozone variability are discussed. Free tropospheric ozone above western North America has increased since the mid‐1990s. Despite an observed drop of ozone in 2020 due to the COVID‐19 economic downturn, this observation‐based study shows the overall free tropospheric ozone trends have not been offset and continued to increase over 1995–2021, mainly driven by strong positive trends in winter and summer. In combination with the strong negative trends observed at rural surface sites over the same period, this study adds to the growing body of evidence that surface trends are frequently disconnected from the general increases observed in the free troposphere. The median free tropospheric trend above western North America (1995–2021) remained positive despite the COVID‐19 economic downturn in 2020Stronger positive ozone trends in all seasons and nearly all percentiles are found above the California subdomainIn contrast ozone is decreasing at rural surface sites, especially at the 95th percentile The median free tropospheric trend above western North America (1995–2021) remained positive despite the COVID‐19 economic downturn in 2020 Stronger positive ozone trends in all seasons and nearly all percentiles are found above the California subdomain In contrast ozone is decreasing at rural surface sites, especially at the 95th percentile

We present a 20 year time series of in situ free tropospheric ozone observations above western North America during springtime and interpret results using hindcast simulations (1980–2014) conducted with the Geophysical Fluid Dynamics Laboratory global chemistry‐climate model (GFDL AM3). Revisiting the analysis of Cooper et al. ([Cooper, O. R., 2010]), we show that sampling biases can substantially influence calculated trends. AM3 cosampled in space and time with observations reproduces the observed ozone trend (0.65 ± 0.32 ppbv yr−1) over 1995–2008 (in simulations either with or without time‐varying emissions), whereas AM3 “true median” with continuous temporal and spatial sampling indicates an insignificant trend (0.25 ± 0.32 ppbv yr−1). Extending this analysis to 1995–2014, we find a weaker ozone trend of 0.31 ± 0.21 ppbv yr−1from observations and 0.36 ± 0.18 ppbv yr−1from AM3 “true median.” Rising Asian emissions and global methane contribute to this increase. While interannual variability complicates the attribution of ozone trends, multidecadal hindcasts can aid in the estimation of robust confidence limits for trends based on sparse observational records. Multidecadal hindcast simulations to interpret O3trends based on incomplete observationsLarge variability in meteorology and sparse in situ sampling complicates O3trend estimatesWhile rising Asian emissions raise U.S. O3background, the model “true median” indicates weaker or insignificant trends

The Soberanes Fire burned 53,470 ha (132,127 acres) along the central California coast between 22 July and 12 October 2016, generating dense smoke and a variety of gaseous compounds that drifted eastward into the San Joaquin Valley Air Basin (SJVAB), an “extreme” nonattainment area for ozone (O3). These gases included nitrogen oxides (NOx) and volatile organic compounds, the photochemical precursors of O3. The fire started during the California Baseline Ozone Transport Study, a field campaign that brought aircraft, surface, and remote sensing measurements of O3and related species to central California. In this paper, we use the California Baseline Ozone Transport Study measurements to assess the impact of the Soberanes Fire on ozone and particulate air quality in the SJVAB. We focus our analysis on 27 July to 2 August when the smoke haze was heaviest and the highest O3concentrations in the SJVAB during 2016 were recorded. Our analyses suggest that while 40 to 60 ppbv of fire‐generated O3was transported to the eastern SJVAB in the 1‐ to 3‐km‐altitude range, relatively little smoke or fire‐generated O3reached the surface in the Visalia area. Aircraft and remote sensing measurements are used to investigate impacts of the Soberanes Fire on air quality in the San Joaquin ValleyOzone enhancements in excess of 50 ppbv were measured by both lidar and aircraft between 1 and 3 km above the surfaceNo significant enhancements in surface ozone were observed

Seasonal methane (CH4) emissions in Northern California are evaluated during this study by using airborne measurement data and inverse model simulations. This research applies Alpha Jet Atmospheric eXperiment (AJAX) measurements obtained during January–February 2013, July 2014, and October–November 2014 over the San Francisco Bay Area (SFBA) and northern San Joaquin Valley (SJV) in order to constrain seasonal CH4emissions in Northern California. The California Greenhouse Gas Emissions Measurement (CALGEM) a priori emission inventory was applied in conjunction with the Weather Research and Forecasting and Stochastic Time-Inverted Lagrangian Transport model and inverse modeling techniques to optimize CH4emissions. Comparing model-predicted CH4mixing ratios with airborne measurements, we find substantial underestimates suggesting that CH4emissions were likely larger than the year 2008 a priori CALGEM emission inventory in Northern California. Using AJAX measurements to optimize a priori emissions resulted in CH4flux estimates from the SFBA/SJV of 1.77?±?0.41, 0.83?±?0.31, and 1.06?±?0.39?Tg?yr-1when using winter, summer, and fall flight data, respectively. Averaging seasonal a posteriori emission estimates (weighted by posterior uncertainties) results in SFBA/SJV annual CH4emissions of 1.28?±?0.38?Tg?yr-1. A posteriori uncertainties are reduced more effectively in the SFBA/SJV region compared to state-wide values indicating that the airborne measurements are most sensitive to emissions in this region. A posteriori estimates during this study suggest that dairy livestock was the source with the largest increase relative to the a priori CALGEM emission inventory during all seasons. Airborne measurements are used to constrain source apportioned methane (CH4) emissions in Northern CaliforniaSeasonal measurements resulted in SFBA/SJV CH4emission estimates ranging from 0.83 ± 0.31 to 1.77 ± 0.41?Tg?yr-1Emission estimates suggest that existing bottom-up CH4emission inventories may underestimate fluxes in California