Greater Magnitude Research Articles

Profiles of stroke regulations discriminate between finishing positions during international open water races

ABSTRACT This study aims to identify stroke regulation profiles and tipping-points in stroke regulation timing during international open water races according to performance level. Twelve elite or world-class swimmers were analysed during 18 international races. Stroke rate and jerk cost were computed cycle-to-cycle using an Inertial Measurement Unit and regulations profiles fitted using polynomials. We performed two-ways mixed-ANOVA to compare stroke kinematics among race segments and performance groups (G1 -fastest- to G3 -slowest-). Swimmers displayed specific regulation profiles (i.e., J-shape with end-spurt, J-shape without end-spurt and reverse L-shape for stroke rate and U-shape, reverse J-shape and reverse L-shape for jerk cost, for respectively G1, G2 and G3) with significant effect of race segment on stroke kinematics for G1 and G2. We highlighted tipping-points in stroke regulations profiles (TP1 and TP2) at respectively 30% and 75% of the race with greater magnitude in G1 than G2. TP1 reflects the end of a stroke economy period (0–30%) and TP2 the end of a progressive increase in stroke kinematics (30–75%) towards end-spurt (75–100%). Open water races follow a high-grading dynamics requiring biomechanical regulations along the race. Targeting stroke rate reserve and management of stroke smoothness should be considered during training of open water swimmers.

Cascading effects of climate change and wildfire on a subarctic lake: A 20‐year case study of watershed change

AbstractMean annual air temperature has been increasing in Alaska since the 1970s and is expected to continue to increase through the current century, resulting in significant environmental changes (e.g., permafrost thaw, shifts in vegetation community composition and distribution, increased wildfire frequency and severity). Because there is little long‐term monitoring data available on lake ecosystems in the subarctic it is difficult to predict how lakes will respond. Here we present data from an ~20‐year long‐term lake and climate monitoring program in Interior Alaska. A significant portion of the lake catchment was burned by wildfires in 1986 and again in 2004. As a result, much of the vegetation in the lake catchment was converted from spruce‐dominated forest to deciduous forest, indicating likely permafrost degradation. At a nearby monitoring site absent of fire effects, mean annual ground temperatures at 50 and 90 cm warmed significantly from about −2°C to about −1°C over the 20‐year monitoring period. Warming of similar or greater magnitude is inferred at the study site due to fire effects. Lake water analyses before and after the 2004 fire show a significant postfire increase in dissolved organic carbon, total nitrogen, and total phosphorous that persisted for a short period (~3 years) and was followed by small, but significant, increases in specific conductance and ion concentrations. Approximately 15 years postfire sulfate and cation concentrations in the lake increased exponentially due to the development of a groundwater seep near the lake. The seep likely formed as a result of permafrost thaw creating new subsurface flowpaths in response to long‐term climate warming and fire effects. In 2021, specific conductance and sulfate concentrations reached 657 μS/cm and 71 mg/L respectively, exceeding tolerance thresholds of the water lily Nuphar lutea. In 2021, N. lutea beds that had occupied the lake since 1981 were no longer visible. Depending on local catchment characteristics, source waters and flow paths contributing to small subarctic lakes will continue to evolve uniquely in response to climate change and thawing permafrost. This case study shows the cascading effects of warming soil and wildfires on catchment characteristics as well as terrestrial and aquatic vegetation and lake water chemistry.

Sleep-like changes in neural processing emerge during sleep deprivation in early auditory cortex.

Insufficient sleep is commonplace in modern lifestyle and can lead to grave outcomes, yet the changes in neuronal activity accumulating over hours of extended wakefulness remain poorly understood. Specifically, which aspects of cortical processing are affected by sleep deprivation (SD), and whether they also affect early sensory regions, remain unclear. Here, we recorded spiking activity in the rat auditory cortex along with polysomnography while presenting sounds during SD followed by recovery sleep. We found that frequency tuning, onset responses, and spontaneous firing rates were largely unaffected by SD. By contrast, SD decreased entrainment to rapid (≥20Hz) click trains, increased population synchrony, and increased the prevalence of sleep-like stimulus-induced silent periods, even when ongoing activity was similar. Recovery NREM sleep was associated with similar effects as SD with even greater magnitude, while auditory processing during REM sleep was similar to vigilant wakefulness. Our results show that processes akin to those in NREM sleep invade the activity of cortical circuits during SD, even in the early sensory cortex.

Perceptions of Autonomous Shuttles for Adults With Spinal Cord Injuries.

Individuals with a spinal cord injury (SCI) have challenges using transportation. Autonomous shuttles (ASs), if accessible, may support their transportation needs. This study quantified the perceptions of AS for adults with and without SCI, before and after riding in the AS. We hypothesized that the perceptions of AS for individuals with SCI would improve, by the greatest magnitude, after riding in the AS. This mixed-method quasi-experimental design included 16 adults with SCI and 16 age-matched controls. While there were no differences between the groups, both groups reported having fewer perceived barriers to using AS after riding in the AS (p = .025). After riding in the AS, both groups stated that the AS must be available, accessible, and affordable if they are to use AS. In conclusion, adults with SCI should experience AS if they are to accept and adopt this mode of transportation.

Effect of Cervical Stenosis and Rate of Impact on Risk of Spinal Cord Injury During Whiplash Injury.

Finite Element Study. To determine the risk of spinal cord injury with pre-existing cervical stenosis during a whiplash injury. Patients with cervical spinal stenosis are often cautioned on the potential increased risk of spinal cord injury (SCI) from minor trauma such as rear impact whiplash injuries. However, there is no consensus on the degree of canal stenosis or the rate of impact that predisposes cervical SCI from minor trauma. A previously validated three-dimensional finite element model of the human head-neck complex with the spinal cord and activated cervical musculature was used. Rear impact acceleration was applied at 1.8m/s and 2.6m/s. Progressive spinal stenosis was simulated at the C5 to C6 segment, from 14mm to 6mm, at 2mm intervals of ventral disk protrusion. Spinal cord von Mises stress and maximum principal strain were extracted and normalized with respect to the 14mm spine at each cervical spine level from C2 to C7. The mean segmental range of motion was 7.3 degrees at 1.8m/s and 9.3 degrees at 2.6m/s. Spinal cord stress above the threshold for SCI was noted at C5 to C6 for 6mm stenosis at 1.8m/s and 2.6m/s. The segment (C6-C7) inferior to the level of maximum stenosis also showed increasing stress and strain with a higher rate of impact. For 8mm stenosis, spinal cord stress exceeded SCI thresholds only at 2.6m/s. Spinal cord strain above SCI thresholds were only noted in the 6mm stenosis model at 2.6m/s. Increased spinal stenosis and rate of impact are associated with greater magnitude and spatial distribution of spinal cord stress and strain during a whiplash injury. Spinal canal stenosis of 6mm was associated with consistent elevation of spinal cord stress and strain above SCI thresholds at 2.6m/s.

Sense of purpose among transgender adults in the United States: comparisons of levels and health correlates

ABSTRACT Given the increased threats to health and well-being faced by transgender individuals, research is needed to understand potential protective factors. Recent work has suggested that a sense of purpose may be one of the health-promoting resources available to marginalized groups, and levels of purpose are often similar or even higher among these groups. However, research is limited regarding whether this factor manifests differently among transgender adults. The current study (n = 1968 U.S. adults; 4.3% identified as transgender) asked participants to complete surveys for sense of purpose, self-rated health, life satisfaction and the type of purposes they deemed important. The findings suggest no difference in levels of sense of purpose between transgender and non-transgender adults. Transgender adults reported slightly lower levels of importance across multiple purposes, which merits further investigation into whether they perceive greater obstacles toward those goals. Of central importance, sense of purpose positively correlated with self-rated health (r = .50) and life satisfaction for transgender adults (r = .77), at similar or even greater magnitudes than for the non-transgender adults. These results point to the potential of exploring sense of purpose as an intervention target for promoting transgender health and well-being, and future directions should focus on the multiple pathways by which transgender identity may influence purpose development.

Antibiotics augment the impact of iron deficiency on metabolism in a piglet model

Infancy and childhood represent a high-risk period for developing iron deficiency (ID) and is a period of increased susceptibility to infectious disease. Antibiotic use is high in children from low-, middle-, and high-income countries, and thus we sought to determine the impact of antibiotics in the context of ID. In this study, a piglet model was used to assess the impact of ID and antibiotics on systemic metabolism. ID was induced by withholding a ferrous sulfate injection after birth to piglets in the ID group and providing an iron deficient diet upon weaning on postnatal day (PD) 25. Antibiotics (gentamicin and spectinomycin) were administered on PD34-36 to a set of control (Con*+Abx) and ID piglets (ID+Abx) after weaning. Blood was analyzed on PD30 (before antibiotic administration) and PD43 (7 days after antibiotic administration). All ID piglets exhibited growth faltering and had lower hemoglobin and hematocrit compared to control (Con) and Con*+Abx throughout. The metabolome of ID piglets at weaning and sacrifice exhibited elevated markers of oxidative stress, ketosis, and ureagenesis compared to Con. The impact of antibiotics on Con*+Abx piglets did not result in significant changes to the serum metabolome 7-days after treatment; however, the impact of antibiotics on ID+Abx piglets resulted in the same metabolic changes observed in ID piglets, but with a greater magnitude when compared to Con. These results suggest that antibiotic administration in the context of ID exacerbates the negative metabolic impacts of ID and may have long lasting impacts on development.

Search strategy analysis reveals sex‐specific deficits in spatial reference memory in 5xFAD mice

AbstractBackgroundSpatial disorientation is one of the earliest symptoms in Alzheimer’s disease. Search strategy classification systems to study navigational deficits in Alzheimer disease have been developed but aren’t widely available. Hence, we studied the navigational strategies in the 5xFAD murine model and evaluated differences between sexes.MethodWe studied spatial reference memory in 3‐month‐, 7‐month‐ and 12‐month‐old female and male 5xFAD mice and their aged‐matched controls in the Morris water maze. Furthermore, a detailed analysis of the swimming strategies using “Pathfinder” was performed. Navigational strategies were classified in spatial (“direct path”, “directed search”, “focal search”, “indirect search”) and non‐spatial categories (“chaining”, “scanning”, “random search”, thigmotaxis”).ResultEscape latency was prolonged in 5xFAD mice compared to WT, only at 7 and 12 months, with greater magnitude in females than males. Regarding search strategies during acquisition training, the most common spatial strategy was “indirect search” whereas “random search” was the most frequent non‐spatial strategy. At 3 months, no clear difference was seen between 5xFAD and WT animals. However, at 7 months, 5xFAD mice used more frequently non‐spatial strategies. Although transgenic mice progressively shifted to more spatial strategies as they learned (mainly “indirect search”), WT animals applied more frequently spatial strategies with higher cognitive value such as “direct path”, “directed search” and “focal search”. In comparison, 12 month‐old 5xFAD mice used more non‐spatial strategies, mainly “random search”, than the WT and their transition to “indirect search” occurred more rarely than in younger mice. Overall, all animals increased the use of non‐spatial strategies as they aged but this increment was greater and earlier in 5xFAD females than in 5xFAD males. Lastly, in the probe trial, 5xFAD female mice at 3 and 12 months applied “random search” more often, while the WT chose “indirect search” with higher frequency. No difference was seen in males during probe trial.ConclusionConventional behavior analysis of escape latencies revealed spatial reference memory deficits in 7m and 12m 5XFAD mice. Deficits in spatial memory were more pronounced in female 5XFAD mice than in male mice. 5XFAD mice, regardless of sex, used a qualitatively and quantitatively different search strategy pattern than WT animals.

Effect of altrenogest on endogenous progesterone during early pregnancy in recipient mares

Altrenogest is commonly utilised for hormonal support of pregnancy, with undefined effects. We investigated effects of altrenogest supplementation on endogenous progesterone (P4) production in embryo recipient mares (RM). RM were managed onsite and selected on the basis of ‘best tone' on transfer day. Thirty RM received a 150mg depot altrenogest intramuscularly from transfer, at 7-day intervals, through to 42 days (ALT), a further 31 RM received no altrenogest (CON). Blood was collected at 7-day intervals, starting 7 days after transfer and P4 assayed by amplified enzyme-linked immunoassay. Data were analysed by total (tP4, ng/ml) and P4 corrected by number of corpora lutea (CL; cP4). Statistical comparisons of non-parametric data were performed by Kruskal-Wallis ANOVA and Friedman repeated measures; values presented as median and 95% confidence interval. Odds ratios (OR) were calculated to evaluate associations between ALT and secondary ovulation, and tP4 values of <3ng/ml. In ALT, tP4 was lower on days 21, 28 and 35 when compared to days 14 and 42 (p<0.01), and no difference was seen between days 14 and 42 (p=0.715). The same pattern was seen with cP4 lower on days 21, 28 and 35 compared to days 14 and 42 (p<0.01), and no difference between days 14 and 42 (p=0.273). A similar profile was seen in CON, with tP4 loweron days 21, 28 and 35 compared to days 14 and 42 (p<0.01) and no difference between days 14 and 42 (p=0.095). However, compared to day 14, cP4 was lower on days 21, 28, 35 (p<0.01), and also on day 42 (p=0.026). When compared to days 21, 28 and 35 there were no differences with day 42 (p>0.10). Secondary CL occurred in 17.24% CON and in 26.67% ALT (OR 1.55; 0.45-5.28, p=0.487). Total P4 was lower in ALT 4.8 (3.9-6.3), compared with CON 6.0 (5.4-7.3, p=0.04), and in ALT 4.7 (3.9-5.3), compared with CON 5.7 (5.1-7.4, p=0.02) at 21 and 28 days respectively. This held true for cP4 at 21 (ALT 3.7; 2.8-4.3 versus CON 4.7; 3.7-6.6, p=0.03) and 28 days (ALT 3.4; 2.5-4.3 versus CON 5.0; 4.0-5.8, p=0.005) where effect of multiple ovulations was nullified. In 40% of ALT, tP4 was <3.0 at ≥1 time-point compared to 3.2% in CON. The odds of a mare having a tP4 concentration <3.0 at any time-point was greater for ALT (OR 11.2; 1.37-91.83, p=0.024). Three ALT (10%) and no CON had tP4 ≤3.0 at 42 days (p=0.212). In conclusion, altrenogest led to suppressed endogenous P4 production with the greatest magnitude at 28 days of gestation; we hypothesize that this is mediated via negative feedback of altrenogest on pituitary LH release and effective reduction of its luteotrophic influence.

Atributos químicos de um argissolo cultivado com cana-de-açúcar após aplicação de doses elevadas de vinhaça

ABSTRACT The use of high doses of vinasse in sugarcane crop can cause modifications in the chemical characteristics of the soil. The aim of this study was to evaluate the effect of the application of high doses of vinasse on the chemical characteristics of an Ultisol cultivated with sugarcane for 210 days. The treatments used were doses equivalent to 0 (D0), 150 (D150), 300 (D300), 600 (D600) and 1200 (D1200) m3 ha-1 of vinasse plus a control treatment with mineral fertilization. The experimental design was completely randomized with six treatments and six repetitions. Exchangeable potassium (K), calcium (Ca), magnesium (Mg) and sodium (Na) contents, organic matter, cation exchange capacity, sodium adsorption ratio, exchangeable sodium percentage, electrical conductivity and pH were analyzed at 90, 120, 150 and 210 days after planting (DAP), in addition to microbial basal respiration at 210 days at depths of 0-0.20 and 0.20-0.40 m. Soil pH increased with the use of vinasse within the proper range for sugarcane, varying from 6.2 to 6.4. The highest K and Na contents were found at D600 and D1200; the highest K and Na availability occurred at 120 DAP and 150 DAP, respectively, indicating competition between these nutrients for exchange sites. Organic matter content was proportionally high according to the vinasse dose applied. D600 and D1200 doses increased Na content in the soil, with greater magnitude at the 0-0.20 m depth.

Pre-estrus progesterone does not affect post-estrus luminal metabolome in cross-bred beef cows.

The concentration of progesterone through the estrous cycle modulates uterine function to affect the luminal metabolome. This paper reports that the dynamic changes in the bovine uterine luminal metabolome during diestrus are independent of the concentration of progesterone in the previous cycle. In cattle, the concentration of sex steroids modulates uterine function, which is reflected in the composition of the luminal metabolome. Ultimately, the uterine luminal metabolome influences embryonic growth and development. Our objectives were (i) to compare the luminal metabolome 4, 7, and 14 days after estrus of cows that were exposed to greater (HP4; n = 16) vs lower (LP4; n = 24) concentrations of progesterone before displaying estrus and ovulating spontaneously and (ii) to identify changes in the luminal concentration of metabolites across these time points. Luminal epithelial cells and fluid were collected using a cytology brush, and gene expression and metabolite concentrations were assessed by RNAseq and targeted mass spectrometry, respectively. Metabolome profile was similar between treatments within each of days 4, 7, and 14 (false discovery rate (FDR): ≥ 0.1). Concentrations of 53 metabolites changed, independent of treatment, across the diestrus. Metabolites were mostly lipids (40 out 53) and the greatest concentrations were at day 14 (FDR: ≤ 0.1). On day 7, the concentration of putrescine and the gene expression of ODC1, PAOX, SLC3A2, and SAT1 increased (P ≤ 0.05). On day 14, the concentration of 3 ceramides, 4 glucosylceramides, and 12 sphingomyelins and the expression of SGMS2 were increased, in addition to the concentration of choline and 20 phosphatidylcholines. Collectively, the post-estrus concentration of luminal metabolites changed dynamically, independent of the concentration of sex steroids on the previous cycle, and the greatest magnitude changes were on day 14 when lipid metabolism was the most enriched pathway.

Global Coronal Malalignment in Degenerative Lumbar Scoliosis and Priority-Matching Correction Technique to Prevent Postoperative Coronal Decompensation.

A prospective case-control study. To analyze global coronal malalignment (GCM) in degenerative lumbar scoliosis (DLS) and to prospectively investigate the performance of priority-matching correction technique on preventing postoperative coronal imbalance. A total of 444 DLS inpatients and outpatients were recruited. GCMs were classified into 2 types: Type 1, GCM with thoracolumbar (TL/L) curve as the main contribution on coronal imbalance; Type 2, GCM with lumbosacral (LS) curve as the main contribution on coronal imbalance. Patients receiving priority-matching correction were assigned to Group P-M and receiving traditional correction were assigned to Group T form August 2020. The fundamental principle of priority-matching technique was to first correct the key curve contributing to coronal imbalance rather than the curve with greater magnitude. Type 1 GCM accounted for 45% and Type 2 GCM accounted for 55% of patients. Type 2 GCM was detected to have greater LS Cobb angle and L4 tilt. At 1-year follow-up, 29.8% of patients with Type 2 GCM, whereas 11.7% of patients with Type 1 GCM were observed to have postoperative coronal decompensation. Patients with postoperative imbalance were revealed to have greater preoperative LS Cobb angle and L4 tilt and smaller correction extent of LS curve and L4 tilt. 6.25% of patients developed postoperative coronal imbalance in Group P-M, whereas 40.5% developed in Group T. Highlighting priority and aggressive correction of the key curve to coronal imbalance, priority-matching technique was proved to be able to limit the development of postoperative coronal decompensation.

Cardiovascular Disease Risk Assessment Using Traditional Risk Factors and Polygenic Risk Scores in the Million Veteran Program

Primary prevention of atherosclerotic cardiovascular disease (ASCVD) relies on risk stratification. Genome-wide polygenic risk scores (PRSs) are proposed to improve ASCVD risk estimation. To determine whether genome-wide PRSs for coronary artery disease (CAD) and acute ischemic stroke improve ASCVD risk estimation with traditional clinical risk factors in an ancestrally diverse midlife population. This was a prognostic analysis of incident events in a retrospectively defined longitudinal cohort conducted from January 1, 2011, to December 31, 2018. Included in the study were adults free of ASCVD and statin naive at baseline from the Million Veteran Program (MVP), a mega biobank with genetic, survey, and electronic health record data from a large US health care system. Data were analyzed from March 15, 2021, to January 5, 2023. PRSs for CAD and ischemic stroke derived from cohorts of largely European descent and risk factors, including age, sex, systolic blood pressure, total cholesterol, high-density lipoprotein (HDL) cholesterol, smoking, and diabetes status. Incident nonfatal myocardial infarction (MI), ischemic stroke, ASCVD death, and composite ASCVD events. A total of 79 151 participants (mean [SD] age, 57.8 [13.7] years; 68 503 male [86.5%]) were included in the study. The cohort included participants from the following harmonized genetic ancestry and race and ethnicity categories: 18 505 non-Hispanic Black (23.4%), 6785 Hispanic (8.6%), and 53 861 non-Hispanic White (68.0%) with a median (5th-95th percentile) follow-up of 4.3 (0.7-6.9) years. From 2011 to 2018, 3186 MIs (4.0%), 1933 ischemic strokes (2.4%), 867 ASCVD deaths (1.1%), and 5485 composite ASCVD events (6.9%) were observed. CAD PRS was associated with incident MI in non-Hispanic Black (hazard ratio [HR], 1.10; 95% CI, 1.02-1.19), Hispanic (HR, 1.26; 95% CI, 1.09-1.46), and non-Hispanic White (HR, 1.23; 95% CI, 1.18-1.29) participants. Stroke PRS was associated with incident stroke in non-Hispanic White participants (HR, 1.15; 95% CI, 1.08-1.21). A combined CAD plus stroke PRS was associated with ASCVD deaths among non-Hispanic Black (HR, 1.19; 95% CI, 1.03-1.17) and non-Hispanic (HR, 1.11; 95% CI, 1.03-1.21) participants. The combined PRS was also associated with composite ASCVD across all ancestry groups but greater among non-Hispanic White (HR, 1.20; 95% CI, 1.16-1.24) than non-Hispanic Black (HR, 1.11; 95% CI, 1.05-1.17) and Hispanic (HR, 1.12; 95% CI, 1.00-1.25) participants. Net reclassification improvement from adding PRS to a traditional risk model was modest for the intermediate risk group for composite CVD among men (5-year risk >3.75%, 0.38%; 95% CI, 0.07%-0.68%), among women, (6.79%; 95% CI, 3.01%-10.58%), for age older than 55 years (0.25%; 95% CI, 0.03%-0.47%), and for ages 40 to 55 years (1.61%; 95% CI, -0.07% to 3.30%). Study results suggest that PRSs derived predominantly in European samples were statistically significantly associated with ASCVD in the multiancestry midlife and older-age MVP cohort. Overall, modest improvement in discrimination metrics were observed with addition of PRSs to traditional risk factors with greater magnitude in women and younger age groups.

Parametric studies on deflection of helical stair slabs

A staircase is an essential component of a building and provides pedestrian access to different floors and roofs of a structure. It has unique geometry among all the structural members and requires special consideration in the design. According to the geometrical classification, the helical staircase is challenging as per design considerations because of its complex geometry. They offer, however, a more gradual ascent and descent, making them safer and more comfortable to use than straight stairs. The complex geometry of the helical staircase requires special consideration to understand its behavior in deflection patterns. The work on staircases having simple geometry has been carried out extensively and is available in the literature. However, limited research has been done in the past for helical staircases. The present study is aimed at parametric investigations of helical staircase slab on its deflection behavior. To analyze the effect of stair slab width and landing, two series of staircases were considered. The first model in the study has a central angle of 180° with varying stair slab widths of 1, 1.5, 2, and 2.5 m. In the second series, a landing was inserted at the central part with the same central angle of 180° to study the effect of landing on the results. The results obtained in the form of deflection contour showed an outward leaning tendency with deflection magnitude increasing as moved radially outward. The deflection increased from zero at fixed ends to a maximum at midspan along the inner and outer edges. The deflection ratio for the outer and inner edges was minimum at starting end of the staircase. At midspan, the outer edge is more prone to deflect with greater magnitude. The deflection with varying landing width comparison revealed that the deflection magnitude decreased with increased landing width at the inner edge. The deflection was, however, directly proportional to the staircase slab width at the outer edge. The deflection pattern remained unchanged when the landing was introduced, but the deflection magnitude was found to be increased in all cases.

SIMPLIFIED MECHANISTIC – EMPIRICAL ANALYSIS OF FLEXIBLE PAVEMENT

Pavement stress-strain analysis is an ideal tool for analytical modelling of pavement behaviour and thus, constitutes an integral part of pavement design and performance evaluation. It is the fundamental basis for the mechanistic design theory. Predicting pavement response by simplified procedure analysis by relying on equivalency factors using axle load spectrum which is obtained from Weigh-In-Motion (WIM) data is aimed for this study. The framework for computing the structural response of the standard axle group loads on a pavement structure by using a layered elastic computer program and calculation of pavement responses for axle load distribution for different axle groups and axle types by using the theoretical analysis. From the study, the summary of the obtained results are as follows: (1) axle load distribution was developed for the four considered axle configurations; (2) Single axle with single tyre has the greatest destructive impact followed by the tridem axle with dual tyres (TRDT) and next by TADT. The least destructive axle group type is the Single Axle with Dual tyre SADT.The predicted pavement response by theoretical analysis indicates that the critical tensile strains obtained results are all greater than the critical vertical strains. At the heaviest axle load, from 70KN, for both SAST and SADT; from 140KN for TADT; and from 210KN, the critical strains have the greatest magnitude by SAST and followed by SADT and next by TADT. The least critical tensile strain is from the TRDT.

Exploration of Sex and Age as Moderators Between Social Cumulative Risk and Sleep in a Representative Sample of Children and Adolescents Living in the United States.

Youth who face adversity are at a disproportionate risk for poor sleep health across the life course. Identifying whether the association between adversity and poor sleep varies based upon age and sex is needed. This study aims to explore sex and age as moderators between social risk and sleep in a sample of U.S. youth. This study analyzed data of 32,212U.S. youth (6-17years) whose primary caregiver participated in the 2017-2018 National Survey of Children's Health. A social cumulative risk index (SCRI) score was calculated from 10 parental, family, and community risk indicators. Nighttime sleep duration was the number of hours the child slept during the past week. Weeknight sleep irregularity was operationalized as whether the child sometimes/rarely/never went to bed at the same time. Generalized logistic regression models estimated associations between SCRI and sleep duration/irregularity, with age and sex as moderators. Age moderated the association between SCRI and short sleep (OR = 1.12, p < 0.001), such that the magnitude of the SCRI-sleep relationship was 12% greater in school-age children. Sex was not a significant moderator. In stratified models by age group, age was positively associated with short sleep in both groups, with a greater magnitude in school-age children. Female school-age children were less likely to have short sleep than males. Younger children with greater social cumulative risk factors may be more vulnerable to short sleep duration. Further research into the mechanisms underlying the relationships between social risk and sleep health in school-age children is needed.

Statistical analysis of ionospheric vertical total electron content anomalies before global Mw≥6.0 shallow earthquakes during 2000–2020

To quantitatively investigate the relationship between earthquakes and ionospheric anomalies, this paper presents a statistical study of pre-earthquake vertical total electron content (VTEC) variations. A total of 1522 shallow (≤60 km) strong (Mw≥6.0) earthquakes in the global area during 2000-2020 are selected, and classified according to different magnitudes, latitudes and focal depths. A quartile-based process with different lengths of sliding windows, equaling 10 days, 15 days and 27 days, respectively, has been utilized to detect VTEC anomalies. The abnormal level is first defined, and then VTEC anomalies occurrence probabilities (Po) and occurrence rates (PE) within 1-10 days before 1522 earthquakes have been calculated. Besides, VTEC anomalies occurrence rates of the background days (PN) are also calculated. The results show that the significant correlation between Po and epicentral latitudinal locations could be observed within 1-10 days before earthquakes. The values of Po increase with larger magnitudes in the equatorial and low-latitude regions, but decrease with greater magnitudes in the mid- and high-latitude regions to some degree. Within 1-5 days before earthquakes, the overall trend of PE shows an increase with larger magnitudes, but the correlation between the values of PE and magnitudes is relatively weak in the southern mid- and high-latitude regions. There is no evident causality between PN and the magnitude, and most of the values of PE/PN are larger than 1, indicating that VTEC anomalies within a few days before earthquakes are probably related with the forthcoming earthquakes. Moreover, when the abnormal level exceeds 60%, different sliding window lengths have a significant impact on the values of Po and PE in the mid- and high-latitude regions. In particular, there are obvious systematic deviations between the values of Po obtained from different sliding windows in the southern mid- and high-latitude regions. However, the selection of the optimal sliding window needs to be further studied.

Abstract 5217: Genome-wide interactions of processed and red meat intake on colorectal cancer risk

Abstract Introduction: Colorectal cancer (CRC) is the third most common cancer, and second cause of cancer death worldwide. High red meat and/or processed meat consumption are established risk factors for CRC. Genome-wide association studies have identified over 200 genetic variants that explain ~20% of the variability in CRC risk. However, few large studies have evaluated genome-wide gene by environment (GxE) interactions with meat in CRC. Using the largest CRC pooled dataset available to date we conducted a genome-wide GxE analysis to identify possible interactions between common variants and red meat and/or processed meat intake and CRC risk. Methods: A pooled sample of 29,912 CRC cases and 39,704 unaffected controls of European (EUR) ancestry from 27 studies was analyzed. Sex- and study-specific quartiles for red meat and processed meat intake were constructed from harmonized questionnaire data on meat consumption. Genotyping arrays were imputated to the Haplotype Reference Consortium. To identify novel CRC interaction loci we used the two-step EDGE method, standard GxE analyses and a 1-3 degrees of freedom (DF) test. We removed previously known GWAS hits and SNPs in high linkage disequilibrium with them. Results: Our Meta-analyses confirmed a positive association between quartile consumption increase of red meat and processed meat with CRC risk (Red meat OR = 1.30; 95%CI = 1.21-1.41; Processed meat OR = 1.40; 95% CI = 1.20 -1.63). Greater magnitude in point estimates were observed for case-control studies compared to cohort studies, for processed meat consumption among men compared to women, and for red meat consumption and distal colon localization compared to proximal colon or rectum. Two DF GxE tests of red meat consumption revealed two SNPs in chromosome (Chr) 8 (rs4871179 &amp; rs75212442) and a SNP in Chr10 (rs117674361) that map downstream HAS2, COLEC10 and downstream CCSER2. In addition, the two-step EDGE GxE method identified the rs35352860 SNP that maps to the SMAD7 gene in Chr18. Genotype-stratified analyses showed that the red meat and CRC risk association was restricted to homozygous carriers of major alleles for rs4871179, rs75212442 &amp; rs117674361. Moreover, we observed dose-response increase in the red meat and CRC risk association with additional copies of the T allele of the SNP in Chr18, with homozygous carriers of the T allele having 46% higher chance of developing CRC associated with high red meat intake; this in contrast to homozygous carriers of the reference C allele, that had an 18% higher risk of developing CRC. No statistically significant GXE interactions with processed meat intake were found. Conclusion: In this large-scale genome-wide GxE analysis we identified interactions between 4 SNPs and red meat consumption affecting CRC risk. The interaction with the SMAD7 rs35352860 SNP provides supportive evidence for a role of heme iron in the carcinogenic pathway of red meat intake in CRC development. Citation Format: Joel Sanchez Mendez, Mariana C. Stern, Andre Kim, John Morrison, Juan P. Lewinger, Li Hsu, Eric Kawaguchi, Ulrike Peters, William J. Gauderman, on behalf of GECCO, CCFR and CORECT. Genome-wide interactions of processed and red meat intake on colorectal cancer risk. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5217.

Exchange Rate Changes and the J-curve Effect: Asymmetric Evidence from a Panel of Five Emerging Market Economies

Using the symmetric and asymmetric specifications of the pooled mean group estimator, we attempted to scrutinise the possibility of the J-curve effect in the case of Brazil, Russia, India, China and South Africa. In addition to both real effective exchange rate changes and nominal effective exchange rate changes, the possible impact of domestic and foreign demand pressures on the trade balance is also estimated. Incorporating a quarterly data set spanning from 2000Q1 to 2020Q2, the results based on the symmetric and asymmetric model establish no evidence of the J-curve phenomenon. However, when asymmetric possibilities are considered, appreciation is found to deteriorate the trade balance relatively by a greater magnitude whereas the impact of currency depreciation is insignificant. In addition, no asymmetric evidence has been reported concerning the effect of domestic and foreign demand. However, a hike in the former deteriorated the trade balance whereas an increase in the latter improved it in both linear and non-linear frameworks. JEL Codes: F4, F41, F42

Life cycle analysis of paver block production using waste plastics: Comparative assessment with concrete paver blocks

Recycling of plastic waste to replace cementitious products to some extent can be a better way to get rid of plastic waste and avoid the use of cement. But to make any innovation into a scale-up technology, a comparative study on environmental emissions is needed. The present study evaluates the environmental emissions from two plastic recycling methods for manufacturing paver blocks (PB) and compares these with the emissions of conventional concrete paver blocks (CCPB). Life cycle analysis (LCA) has been performed on three PB manufacturing processes (CCPB, Plastic as filler paver blocks (PFPB) and Plastic as binder paver blocks (PBPB)) considering the impacts from materials and energy interaction in each step and operation. The impacts obtained from the CML 2001 and TRACI methods have shown that the emissions from PFPB (GWP 21.4 kg CO2 eq.) and CCPB (GWP 16 kg CO2 eq.) are almost 2.2 and 1.6 times higher than PBPB (GWP 9.86 kg CO2 eq.). The LCA study shows that use of cement has major contribution (for instance >80% in GWP category) to overall emissions for PFPB and CCPB. The sensitivity analysis elucidates that transportation distance and truck payload for CCPB and PFPB processes and electricity consumption for PBPB, shift the impacts in greater magnitude (±3–10%) by ±20% variation in input parameter values. The LCA study concludes that the PB manufacturing by complete replacement of cement is more environment-friendly process than PFPB and CCPB. The use of electricity from solid biomass and hydropower can reduce the GWP by 77% and 83% respectively.