[Effects of"Grain for Green "on the Spatial Distribution of Soil Carbon and Nitrogen in Purple Hilly Area of China].

In order to remedy the lack of research on the effect of "Grain for Green" on soil carbon （C） and nitrogen （N） distribution on slope soil in purple hilly areas of Sichuan Basin, China, a study was conducted on a long-term observation site established in the Wanan small watershed of Yanting Agro-ecological Experimental Station of Purple Soil, Chinese Academy of Sciences. The morphology, content, and storage of C and N in soil at different slope positions of farmland and the artificial forests in rehabilitated land with a history of approximately 30 years were compared. Our results showed that "Grain for Green" significantly increased soil organic carbon （SOC） content and SOC stock in all soil layers. The SOC stock of the surface layer （0-20 cm） increased by 25.86 t·hm-2, and the annual SOC stocks ratio was 0.89 t·hm-2. Soil total nitrogen （TN） content increased slightly but only in the 0-20 cm soil layer. Compared with those in sloping farmland, the differences in available C and N nutrients such as soil nitrate N （NO3--N）, ammonia N （NH4+-N）, and dissolved organic C （DOC） in the whole soil profile （0-70 cm） were basically not significant （P > 0.05）. In addition, our research also found that slope position had significant effects on the contents of TN, SOC, NO3--N, NH4+-N, and DOC in farmland soil （P< 0.05）. The variation trend of soil NO3--N, NH4+-N, and DOC contents along the slope was as follows： upper slope < middle slope < lower slope, whereas the soil TN and SOC contents were highest in the lower slope, followed by the upper slope and middle slope. The position of the slope had a significant impact only on DOC content in forest soil, which increased along the slope. This research indicated that when evaluating the impact of land use changes on soil C and N stocks in the purple soil hilly region, the influence of topographic factors cannot be ignored.

Fingerprinting Organofluorine Molecules via Position-Specific Isotope Analysis.

Organofluorine substances are found in a wide range of materials and solvents commonly used in industry and homes, as well as pharmaceuticals and pesticides. In the environment, organofluorine molecules are now recognized as an important class of anthropogenic pollutants. Fingerprinting organofluorine compounds via their carbon isotope ratios (13C/12C) is crucial for correlating molecules with their source. Here we apply a 19F nuclear magnetic resonance spectroscopy (NMR) technique to obtain the first position-specific carbon isotope ratios for a diverse set of organofluorine molecules. In contrast to traditional isotope ratio mass spectrometry, the 19F NMR method provides 13C/12C isotope ratios at each carbon position where a C-F bond is present, and does not require fragmentation or combustion to CO2, overcoming challenges posed by the robust C-F covalent bonds. The method was validated with 2,2,2-trifluoroethanol, and applied to analyze heptafluorobutanoic acid, 5-fluorouracil and fipronil. Results reveal distinct intramolecular carbon isotope distributions, enabling differentiation of chemically identical molecules. Notably, the NMR method accurately analyzes carbon isotopes within target molecules despite impurities. Potential applications include the detection of counterfeit products and drugs, and ultimately pollution tracking in the environment.

Changes in the anteroposterior position of the femur relative to the tibia impact patient satisfaction in total knee arthroplasty.

BACKGROUND: In this study, we aimed to investigate the preoperative and postoperative anteroposterior position (AP) of the femur relative to the tibia in total knee arthroplasty (TKA) and assess the influence of change in the AP position on clinical outcomes. METHODS: We evaluated 49 knees that underwent bi-cruciate-substituted TKA using a navigation system. The preoperative and postoperative AP position of the femur relative to the tibia at maximum extension, 15°, 30°, 45°, 60°, 90°, 105°, and 120° and maximum flexion angles were calculated. The 2011 Knee Society Score was evaluated preoperatively and 1 year postoperatively. The Wilcoxon signed rank and Spearman's rank correlation tests were performed, with statistical significance set at P < 0.05. RESULTS: The postoperative AP position was significantly correlated with the preoperative AP position at each measured angle. The postoperative AP positions were statistically more anterior than those preoperatively. Furthermore, the changes in the AP position after TKA negatively correlated with the symptom (P = 0.027 at 30°, P = 0.0018 at 45°, P = 0.0003 at 60°, P = 0.01 at 90°, and P = 0.028 at 105°) and patient satisfaction (P = 0.018 at 60° and P = 0.009 at 90°) scores at 1 year postoperatively. CONCLUSION: The postoperative AP position of the femur relative to the tibia was strongly influenced by the preoperative those in TKA. Postoperative anterior deviation of the femur relative to the tibia from mid-flexion to deep flexion could worsen clinical outcomes.

Correlation between surgical position and neck pain in patients undergoing thyroidectomy: a prospective observational study.

BACKGROUND: Thyroid diseases are one of the most common health problems worldwide. Although they represent a necessary step in order to perform thyroidectomy, hyperextension of the neck can potentially increase postoperative pain. The aim of this study is to determine a correlation between the degree of neck hyperextension on the operative table and the postoperative pain in patients undergoing open thyroidectomy. METHODS: Patients were prospectively enrolled from the cohort of patients operated at the Endocrine Surgery Unit of the University Hospital of Pisa, between May and July 2021. Both of patients who underwent total thyroidectomy or hemi-thyroidectomy were recruited. The following data were analysed in order to find a correlation with postoperative pain at 24 h: age, gender, type of surgery, BMI, operative time, and degree of neck extension. RESULTS: Overall, 195 patients were enrolled. A direct, statistically significant correlation emerged between the degree of neck hyperextension and the postoperative pain 24 h after surgery, regardless of the pain of the surgical wound (p < 0.001; beta 0.270). CONCLUSIONS: A direct correlation emerges between neck tilt angle and postoperative neck pain. Moreover, total thyroidectomy (TT) predisposes more to postoperative neck pain, considering the type of surgery.

Effects of Whole-Body Vibration Therapy in Weight-Bearing and Non-Weight Bearing Positions for Upper and Lower Extremities on Balance and Cervical Joint Position Sense in Children With Cerebral Palsy.

INTRODUCTION: Cerebral palsy (CP) is a complex pathological entity that affects muscular control, coordination, proprioception, fine and gross motor abilities, position, stability, and, in some cases, cognition. This study aimed to compare the effects of whole-body vibration therapy (WBVT) in weight bearing and non-weight bearing positions for the upper and lower extremities on balance and cervical joint position sense in children with spastic CP. METHODS: A randomized controlled trial was carried out on 60 hemiplegic children with spastic CP aged 5-15 years. Following randomization, all participants were allocated into six equal-sized groups based on the application of WBVT for upper extremities, lower extremities, or both simultaneously in either weight-bearing or non-weight-bearing positions. Pediatric balance scale (PBS) and laser tracker system were used to assess functional balance and cervical joint position sense. RESULTS: One-way analysis of variance for Inter-group analysis showed a statistically significant difference among all groups in PBS and cervical joint position sense (p<0.05). CONCLUSION: WBVT was found to be beneficial in improving balance and cervical joint position sense in both weight-bearing and non-weight-bearing positions for the upper and lower extremities in children with cerebral palsy. However, the simultaneous application of WBVT in weight-bearing positions for both upper and lower extremities showed the most significant improvements in improving both balance and cervical joint position sense, indicating the most efficacious position of this treatment approach in children with cerebral palsy.

Retractable congestive heart failure due to sinus valsalva rupture with coexisting gerbode defect: a rare case report.

Sinus of Valsalva aneurysm (SoVA) is a rare disease with less than 1% prevalence in the population. Most cases are asymptomatic, however, significant clinical manifestations are possible due to fistula formation and sudden rupture resulting in cardiac shunt. Eventually it may develop into progressive heart failure with high morbidity. We report the case of a 33 year old female patient who presented with shortness of breath, ascites, and recurring hospitalisation. The cardiac examination revealed sinus tachycardia along with loud and continuous murmurs on the left parasternal border. Several standard diagnostic procedures could not be performed due to malignant arrhythmia in supine position. Echocardiography examination revealed SoV rupture with a gerbode defect, which was the underlying cause of severe retractable heart failure.

Evaluation of the effect of trendelenburg position duration on intracranial pressure in laparoscopic hysterectomies using ultrasonographic optic nerve sheath diameter measurements.

BACKGROUND: During laparoscopic surgery, pneumoperitoneum and Trendelenburg positioning applied to provide better surgical vision can cause many physiological changes as well as an increase in intracranial pressure. However, it has been reported that cerebral autoregulation prevents cerebral edema by regulating this pressure increase. This study aimed to investigate whether the duration of the Trendelenburg position had an effect on the increase in intracranial pressure using ultrasonographic optic nerve sheath diameter (ONSD) measurements. METHODS: The near infrared spectrometry monitoring of patients undergoing laparoscopic hysterectomy was performed while awake (T0); at the fifth minute after intubation (T1); at the 30th minute (T2), 60th minute (T3), 75th minute (T4), and 90th minute (T5) after placement in the Trendelenburg position; and at the fifth minute after placement in the neutral position (T6). RESULTS: The study included 25 patients. The measured ONSD values were as follows: T0 right/left, 4.18±0.32/4.18±0.33; T1, 4.75±0.26/4.75±0.25; T2, 5.08±0.19/5.08±0.19; T3, 5.26±0.15/5.26±0.15; T4, 5.36±0.11/5.37±0.12; T5, 5.45±0.09/5.48±0.11; and T6, 4.9±0.24/4.89±0.22 ( p < 0.05 compared with T0). ). No statistical difference was detected in all measurements in terms of MAP, HR and ETCO2 values compared to the T0 value (p > 0.05). CONCLUSIONS: It was determined that as the Trendelenburg position duration increased, the ONSD values ​​increased. This suggests that as the duration of Trendelenburg positioning and pneumoperitoneum increases, the sustainability of the mechanisms that balance the increase in intracranial pressure becomes insufficient. TRIAL REGISTRATION: This study was registered at Clinical Trials.gov on 21/09/2023 (registration number NCT06048900).

Challenging trophic position assessments in complex ecosystems: Calculation method, choice of baseline, trophic enrichment factors, season and feeding guild do matter: A case study from Marquesas Islands coral reefs.

Assessments of ecosystem functioning are a fundamental ecological challenge and an essential foundation for ecosystem-based management. Species trophic position (TP) is essential to characterize food web architecture. However, despite the intuitive nature of the concept, empirically estimating TP is a challenging task due to the complexity of trophic interaction networks. Various methods are proposed to assess TPs, including using different sources of organic matter at the base of the food web (the 'baseline'). However, it is often not clear which methodological approach and which baseline choices are the most reliable. Using an ecosystem-wide assessment of a tropical reef (Marquesas Islands, with available data for 70 coral reef invertebrate and fish species), we tested whether different commonly used TP estimation methods yield similar results and, if not, whether it is possible to identify the most reliable method. We found significant differences in TP estimates of up to 1.7 TPs for the same species, depending on the method and the baseline used. When using bulk stable isotope data, the choice of the baseline significantly impacted TP values. Indeed, while nitrogen stable isotope (δ15N) values of macroalgae led to consistent TP estimates, those using phytoplankton generated unrealistically low TP estimates. The use of a conventional enrichment factor (i.e. 3.4‰) or a 'variable' enrichment factor (i.e. according to feeding guilds) also produced clear discrepancies between TP estimates. TPs obtained with δ15N values of source amino acids (compound-specific isotope analysis) were close to those assessed with macroalgae. An opposite seasonal pattern was found, with significantly lower TPs in winter than in summer for most species, with particularly pronounced differences for lower TP species. We use the observed differences to discuss possible drivers of the diverging TP estimates and the potential ecological implications.

JointTracker: Real-time inertial kinematic chain tracking with joint position estimation.

In-field human motion capture (HMC) is drawing increasing attention due to the multitude of application areas. Plenty of research is currently invested in camera-based (markerless) HMC, with the advantage of no infrastructure being required on the body, and additional context information being available from the surroundings. However, the inherent drawbacks of camera-based approaches are the limited field of view and occlusions. In contrast, inertial HMC (IHMC) does not suffer from occlusions, thus being a promising approach for capturing human motion outside the laboratory. However, one major challenge of such methods is the necessity of spatial registration. Typically, during a predefined calibration sequence, the orientation and location of each inertial sensor are registered with respect to the underlying skeleton model. This work contributes to calibration-free IHMC, as it proposes a recursive estimator for the simultaneous online estimation of all sensor poses and joint positions of a kinematic chain model like the human skeleton. The full derivation from an optimization objective is provided. The approach can directly be applied to a synchronized data stream from a body-mounted inertial sensor network. Successful evaluations are demonstrated on noisy simulated data from a three-link chain, real lower-body walking data from 25 young, healthy persons, and walking data captured from a humanoid robot. The estimated and derived quantities, global and relative sensor orientations, joint positions, and segment lengths can be exploited for human motion analysis and anthropometric measurements, as well as in the context of hybrid markerless visual-inertial HMC.

SymTC: A symbiotic Transformer-CNN net for instance segmentation of lumbar spine MRI.

Intervertebral disc disease, a prevalent ailment, frequently leads to intermittent or persistent low back pain, and diagnosing and assessing of this disease rely on accurate measurement of vertebral bone and intervertebral disc geometries from lumbar MR images. Deep neural network (DNN) models may assist clinicians with more efficient image segmentation of individual instances (discs and vertebrae) of the lumbar spine in an automated way, which is termed as instance image segmentation. In this work, we proposed SymTC, an innovative lumbar spine MR image segmentation model that combines the strengths of Transformer and Convolutional Neural Network (CNN). Specifically, we designed a parallel dual-path architecture to merge CNN layers and Transformer layers, and we integrated a novel position embedding into the self-attention module of Transformer, enhancing the utilization of positional information for more accurate segmentation. To further improve model performance, we introduced a new data synthesis technique to create synthetic yet realistic MR image dataset, named SSMSpine, which is made publicly available. We evaluated our SymTC and the other 16 representative image segmentation models on our private in-house dataset and public SSMSpine dataset, using two metrics, Dice Similarity Coefficient and the 95th percentile Hausdorff Distance. The results indicate that SymTC surpasses the other 16 methods, achieving the highest dice score of 96.169 % for segmenting vertebral bones and intervertebral discs on the SSMSpine dataset. The SymTC code and SSMSpine dataset are publicly available at https://github.com/jiasongchen/SymTC.

Do Birth Outcomes Predicted by Occipital Position Inform Definitions of Occiput Posterior and Occiput Transverse?

Fetal head position significantly influences birth outcomes, with higher rates of complications observed when the fetal head is in the Occiput Posterior (OP) position compared to Occiput Transverse (OT) or Occiput Anterior (OA) positions. There is no consensus in the current literature on the precise rotational point at which the fetal occiput shifts from posterior to transverse, reducing clarity in both scientific and clinical communication. Different studies employ varying definitions of these positions, which affects management decisions. This study aims to determine if a definable threshold exists between the directly posterior and directly transverse positions that correlates with different birth outcomes, thereby proposing a consistent and clinically useful definition for OP versus OT. We analyzed ultrasound data from 570 patients at full dilatation from five previous studies, correlating the angle of the fetal occiput (noted on a clock-face) with birth outcomes. Adverse outcomes were defined as cesarean delivery, instrumental vaginal delivery, significant postpartum hemorrhage (500 ml or more), obstetric anal sphincter injury, five-minute Apgar scores <7, arterial cord pH <7, base excess less than -12, or neonatal intensive care unit admission. The analysis was conducted using SAS version 9.4. The study found a continuous relationship between the fetal occipital angle and adverse birth outcomes without a distinct threshold separating OP from OT positions. No clear inflection point was demonstrated in pregnancy outcomes between OT and OP. The relationship between the angle of occiput position and pregnancy outcomes was continuous: the closer the fetal head was to directly OP, the higher the likelihood of adverse outcomes. Given the lack of a clear cut-off and to improve consistency in future research, we recommend dividing the occiput position into four quadrants of 90 degrees each. This classification could standardize reporting and potentially improve clinical decision-making regarding fetal position during labor.

Bayes-xG: player and position correction on expected goals (xG) using Bayesian hierarchical approach.

This study employs Bayesian methodologies to explore the influence of player or positional factors in predicting the probability of a shot resulting in a goal, measured by the expected goals (xG) metric. Utilising publicly available data from StatsBomb, Bayesian hierarchical logistic regressions are constructed, analysing approximately 10,000 shots from the English Premier League (for the years of 2003 and 2015) to ascertain whether positional or player-level effects impact xG. The findings reveal positional effects in a basic model that includes only distance to goal and shot angle as predictors, highlighting that strikers and attacking midfielders exhibit a higher likelihood of scoring. However, these effects diminish when more informative predictors are introduced. Nevertheless, even with additional predictors, player-level effects persist, indicating that certain players possess notable positive or negative xG adjustments, influencing their likelihood of scoring a given chance. The study extends its analysis to data from Spain's La Liga ( ≈ 20 K shots from 1973 and 2004 to 2020) and Germany's Bundesliga ( ≈ 7.5 K shots from 2015), yielding comparable results. Additionally, the paper assesses the impact of prior distribution choices on outcomes, concluding that the priors employed in the models provide sound results but could be refined to enhance sampling efficiency for constructing more complex and extensive models feasibly.

Shoulder muscle weakness and proprioceptive impairments in type 2 diabetes mellitus: exploring correlations for improved clinical management.

Background: Type 2 diabetes mellitus (T2DM) is a prevalent metabolic disorder with systemic implications, potentially affecting musculoskeletal health. This study aimed to assess shoulder muscle strength and joint repositioning accuracy in individuals with T2DM, exploring potential correlations and shedding light on the musculoskeletal consequences of the condition. The objectives were two-fold: (1) to assess and compare shoulder strength and joint repositioning accuracy between individuals with T2DM and asymptomatic counterparts, and (2) to examine the correlation between shoulder strength and joint repositioning accuracy in individuals with T2DM. Methods: A cross-sectional study enrolled 172 participants using the convenience sampling method, including 86 individuals with T2DM and an age-matched asymptomatic group (n = 86). Shoulder strength was assessed using a handheld dynamometer, while joint repositioning accuracy was evaluated with an electronic digital inclinometer. Results: Individuals with T2DM exhibited reduced shoulder muscle strength compared to asymptomatic individuals (p < 0.001). Additionally, joint repositioning accuracy was significantly lower in the T2DM group (p < 0.001). Negative correlations were observed between shoulder strength and joint repositioning accuracy in various directions (ranging from -0.29 to -0.46, p < 0.001), indicating that higher muscle strength was associated with improved joint repositioning accuracy in individuals with T2DM. Conclusion: This study highlights the significant impact of T2DM on shoulder muscle strength and joint repositioning accuracy. Reduced strength and impaired accuracy are evident in individuals with T2DM, emphasizing the importance of addressing musculoskeletal aspects in diabetes management. The negative correlations suggest that enhancing shoulder muscle strength may lead to improved joint repositioning accuracy, potentially contributing to enhanced physical functioning in this population.

Building a Hospital Pharmacist Workforce by a Diversified and Position-Oriented Learning System.

Background: The role of hospital pharmacists has shifted from primarily ensuring drug supply to providing comprehensive pharmaceutical care. To accommodate this shift, new positions are needed. The traditional training model for hospital pharmacists is no longer sufficient for the evolving demands of pharmaceutical care and these new roles. This study aimed to describe the development of a position-oriented learning system explicitly tailored for hospital pharmacists and to assess its impact on workforce development and pharmacy service. Methods: The position-oriented learning system for hospital pharmacists, aimed at enhancing training and workforce development, was evaluated based on two critical criteria: the completion rate of learning modules and the subsequent improvement in pharmaceutical care at the hospital. The completion rate assessed the engagement and effectiveness of the training content. At the same time, the improvement in pharmaceutical care evaluated practical outcomes such as percentages of patients who received pharmaceutical care and percentages of inappropriate medication orders intercepted. Results: In 2021, 218 employees participated in the learning system. The pharmacy department has identified 22 pharmacists for various positions through this system. The quantity and quality of pharmaceutical care have improved significantly. Conclusion: The position-oriented diversified learning system achieves the perfect combination of department development direction and individual career planning of employees. The learning system can significantly improve the learning efficiency of pharmacists, enhance the quality of various pharmaceutical care, and promote the development of disciplines.

Finite element analysis of mechanical stress in a cementless tapered-wedge short stem in the varus position.

BACKGROUND: In recent years, the use of tapered-wedge short stems has increased due to their ability to preserve bones and tendons. Surgical techniques occasionally result in a varus position of the stem, which is particularly pronounced in short stems. Although the varus position is not clinically problematic, there are reports of an increased incidence of stress shielding and cortical hypertrophy. Thus, we evaluated and examined the acceptable range of varus angles using finite element analysis. METHODS: Patients diagnosed with osteoarthritis of the hip joint who had undergone arthroplasty were selected and classified into three types [champagne-flute (type A), intermediate (type B), and stovepipe (type C)]. Finite element analysis was performed using Mechanical Finder. The model was created using a Taperloc microplasty stem with the varus angle increased by 1° from 0° to 5° from the bone axis and classified into seven zones based on Gruen's zone classification under loading conditions in a one-leg standing position. The volume of interest was set, the mean equivalent stress for each zone was calculated. RESULTS: A significant decrease in stress was observed in zone 2, and increased stress was observed in zones 3 and 4, suggesting the emergence of a distal periosteal reaction, similar to the results of previous studies. In zone 2, there was a significant decrease in stress in all groups at a varus angle ≥ 3°. In zone 3, stress increased from ≥ 3° in type B and ≥ 4° in type C. In zone 4, there was a significant increase in stress at varus angles of ≥ 2° in types A and B and at ≥ 3° in type C. CONCLUSION: In zone 2, the varus angle at which stress shielding above Engh classification grade 3 may appear is expected to be ≥ 3°. Distal cortical hypertrophy may appear in zones 3 and 4; the narrower the medullary cavity shape, the smaller the allowable angle of internal recession, and the wider the medullary cavity shape, the wider the allowable range. Long-term follow-up is required in patients with varus angles > 3°.

Component rotational mismatch in the standing position is a potential risk factor for unfavourable functional outcomes after total knee arthroplasty.

Purpose: This study assessed rotational mismatch between components after total knee arthroplasty (TKA) in the supine and standing positions and aimed to investigate the effect of rotational mismatch in the standing position on postoperative patient-reported outcome measures (PROMs). Methods: Seventy-one patients (71 knees) who underwent TKA for medial knee osteoarthritis were used to investigate rotational mismatches between components. Rotational mismatches between components were examined on postoperative standing whole-leg and supine knee radiographs using a three-dimensional-to-two-dimensional model image registration technique, and the angles between the reference axes of the components were measured. Component alignment was evaluated using postoperative computed tomography images, and a questionnaire (2011 version of the Knee Society Score: [KSS 2011]) was mailed to investigate postoperative PROMs. Results: In the entire cohort, rotational mismatches in the supine and standing positions were similar (p = 0.9315). In 15% of patients, the mismatch was large (>5°) in the supine position but small (<5°) in the standing position (overestimated group). However, in 23% of patients, the mismatch was small (<5°) in the supine position and large (>5°) in the standing position (underestimated group). The underestimated group had severe preoperative varus deformity, resulting in external rotation of both femoral and tibial components. Rotational mismatch in the standing position (p = 0.0032) was a significant risk factor for unfavourable PROMs. Patients with a mismatch in the standing position had significantly lower scores than those without a mismatch (p = 0.0215), exceeding the minimal clinically important difference values. Conclusions: The underestimated group is clinically important because the surgical procedure and intraoperative assessment of component placement are performed in the supine position. In cases of severe preoperative varus deformity, care should be taken not to place the component in malrotation to avoid rotational mismatch in the standing position. Level of Evidence: Ⅳ, Case series.

Playing position and match location affect the number of high-intensity efforts more than the quality of the opposition in elite football players.

This study aimed to examine the impact of playing position (PP), match location (ML), and opposition standard (OS) on team and individual acceleration (ACC) and deceleration (DEC) efforts. Fifty professional football players were monitored across 24 English Premier Development League matches during the 2020/21 season. High-intensity ACC and DEC thresholds were set at > +3 m · s-2 and < -3 m · s-2, respectively. Players were divided into five PPs: centre backs (CB; n = 68), full-backs (FB; n = 24), centre midfielders (CM; n = 54), wide midfielders (WM; n = 15), centre forwards (CF; n = 27). Opposition standard was categorised as Top (1st-4th), Middle (5th-9th), and Bottom (9th-13th) based on final league ranking of the study season. Each match location was classified as Home or Away. One way analysis of variance (ANOVA) and a multivariate ANOVA analysed the independent effect of PP, ML and OS on ACC and DEC efforts, and the interaction of all contextual factors, respectively. Acceleration efforts were affected by PP and ML. FB performed 22% more ACC than WM. All players performed 6% more ACC actions during home matches compared to away fixtures. DEC efforts were only affected by PP, with FB and CM executing 26% and 32% greater DEC efforts than CB, respectively. When playing against top or middle teams at home, CB, CM, and CF tended to perform more high-intensity actions than when playing away. In contrast, when playing against top teams at home, FB and WM performed fewer high-intensity actions than when playing away. Playing position and ML affected ACC and DEC actions but not OS.

Is social disadvantage a chronic stressor? Socioeconomic position and HPA axis activity among older adults living in England.

INTRODUCTION: Living in socioeconomic disadvantage has been conceptualised as a chronic stressor, although this contradicts evidence from studies using hair cortisol and cortisone as a measure of hypothalamus-pituitary-adrenal (HPA)1 axis activity. These studies used complete case analyses, ignoring the impact of missing data for inference, despite the high proportion of missing biomarker data. The methodological limitations of studies investigating the association between socioeconomic position (SEP)2 defined as education, wealth, and social class and hair cortisol and cortisone are considered in this study by comparing three common methods to deal with missing data: (1) Complete Case Analysis (CCA),3 (2) Inverse Probability Weighting (IPW) 4and (3) weighted Multiple Imputation (MI).5 This study examines if socioeconomic disadvantage is associated with higher levels of HPA axis activity as measured by hair cortisol and cortisone among older adults using three approaches for compensating for missing data. METHOD: Cortisol and cortisone levels in hair samples from 4573 participants in the 6th wave (2012-2013) of the English Longitudinal Study of Ageing (ELSA)6 were examined, in relation to education, wealth, and social class. We compared linear regression models with CCA, weighted and multiple imputed weighted linear regression models. RESULTS: Social groups with certain characteristics (i.e., ethnic minorities, in routine and manual occupations, physically inactive, with poorer health, and smokers) were less likely to have hair cortisol and hair cortisone data compared to the most advantaged groups. We found a consistent pattern of higher levels of hair cortisol and cortisone among the most socioeconomically disadvantaged groups compared to the most advantaged groups. Complete case approaches to missing data underestimated the levels of hair cortisol in education and social class and the levels of hair cortisone in education, wealth, and social class in the most disadvantaged groups. CONCLUSION: This study demonstrates that social disadvantage as measured by disadvantaged SEP is associated with increased HPA axis activity. The conceptualisation of social disadvantage as a chronic stressor may be valid and previous studies reporting no associations between SEP and hair cortisol may be biased due to their lack of consideration of missing data cases which showed the underrepresentation of disadvantaged social groups in the analyses. Future analyses using biosocial data may need to consider and adjust for missing data.