Grayson County TX Historical Markers

Presentation containing photographs of historic markers in Grayson County, Texas, organized alphabetically by city name. Each site slide includes the name, a photograph of the marker, and (when relevant) a photograph of the building or area described by the marker

Variation in mandible shape and body size of house mice Mus musculus in five separate New Zealand forest habitats

This study investigates variation in house mouse Mus musculus body size and mandible shape across New Zealand, using geometric morphometrics and biomechanical advantage analyses. The Mus phylogroups currently known in New Zealand include Mus musculus domesticus, M. m. musculus and M. m. castaneus. We examined samples of house mice inhabiting five different podocarp and beech forest environments across the North and South Islands (Pureora Forest, Zealandia Wildlife Sanctuary, Craigieburn Forest Park, Eglinton Valley and Hollyford Valley). Significant variation in mandible shape and body size was found between all five forest populations. South Island mice had larger bodies and greater mechanical advantage in the temporalis muscle compared with their North Island counterparts. Zealandia Sanctuary mouse mandibles were broader and shorter than South Island mouse mandibles, and had greater masseter muscle advantage. Centroid size and body weight, but not head-body length, varied significantly with two distinct genetic haplotypes. Finally, annual rainfall was the most significant covariate with mandible shape. Higher rainfall locations were generally associated with soft-food related mandible shapes, while lower rainfall correlated with hard-food mandible shapes. This preliminary investigation provides the framework for further research into mandible shape and body size variation in New Zealand house mice

Breastfeeding, the use of docosahexaenoic acid-fortified formulas in infancy and neuropsychological function in childhood

OBJECTIVE: To investigate the relation between breastfeeding, use of docosahexaenoic acid (DHA)-fortified formula and neuropsychological function in children. DESIGN: Prospective cohort study. SETTING: Southampton, UK. SUBJECTS: 241 children aged 4 years followed up from birth. MAIN OUTCOME MEASURES: IQ measured by the Wechsler Pre-School and Primary Scale of Intelligence (3rd edn), visual attention, visuomotor precision, sentence repetition and verbal fluency measured by the NEPSY, and visual form-constancy measured by the Test of Visual-Perceptual Skills (Non-Motor). RESULTS: In unadjusted analyses, children for whom breast milk or DHA-fortified formula was the main method of feeding throughout the first 6 months of life had higher mean full-scale and verbal IQ scores at age 4 years than those fed mainly unfortified formula. After adjustment for potential confounding factors, particularly maternal IQ and educational attainment, the differences in IQ between children in the breast milk and unfortified formula groups were severely attenuated, but children who were fed DHA-fortified formula had full-scale and verbal IQ scores that were respectively 5.62 (0.98 to 10.2) and 7.02 (1.56 to 12.4) points higher than children fed unfortified formula. However, estimated total intake of DHA in milk up to age 6 months was not associated with subsequent IQ or with score on any other test. CONCLUSIONS: Differences in children's intelligence according to type of milk fed in infancy may be due more to confounding by maternal or family characteristics than to the amount of long-chain polyunsaturated fatty acids they receive in milk

Paving the path for injury prevention in rugby-7s:A systematic review and meta-analysis

This review and meta-analysis aimed to describe the current rugby-7s injury epidemiological literature by examining injury data from both sexes, all levels of play, and their associated risk factors. Studies published up until March 2024 were included. These studies were retrieved from six databases using search terms related to rugby-7s or sevens, tackle, collision, collision sport, injury, athlete, incidence rate, mechanism, and risk factor. Only peer-reviewed original studies using prospective or retrospective cohort designs with a clearly defined rugby-7s sample were considered. Included studies needed to report one injury outcome variable. Non-English and qualitative studies; reviews, conference papers, and abstracts were excluded. Twenty studies were included. The meta-analysis used the DerSimonian–Laird continuous random-effects method to calculate the pooled estimated means and 95% confidence interval. The estimated mean injury incidence rate for men was 108.5/1000 player-hours (95% CI: 85.9–131.0) and 76.1/1000 player-hours (95% CI: 48.7–103.5) for women. The estimated mean severity for men was 33.9 days (95% CI: 20.7–47.0) and 44.2 days (95% CI: 32.1–56.3) for women. Significantly more match injuries occurred in the second half of matches, were acute, located at the lower limb, diagnosed as joint/ligament, and resulted from being tackled. Fatigue, player fitness, and previous injuries were associated with an increased risk of injury. There were no statistically significant differences between women's and men's injury profiles. However, the inherent cultural and gendered factors which divide the two sports should not be ignored. The findings from this review will help pave the way forward beyond the foundational stages of injury prevention research in rugby-7s.</p

Paving the path for injury prevention in rugby-7s:A systematic review and meta-analysis

This review and meta-analysis aimed to describe the current rugby-7s injury epidemiological literature by examining injury data from both sexes, all levels of play, and their associated risk factors. Studies published up until March 2024 were included. These studies were retrieved from six databases using search terms related to rugby-7s or sevens, tackle, collision, collision sport, injury, athlete, incidence rate, mechanism, and risk factor. Only peer-reviewed original studies using prospective or retrospective cohort designs with a clearly defined rugby-7s sample were considered. Included studies needed to report one injury outcome variable. Non-English and qualitative studies; reviews, conference papers, and abstracts were excluded. Twenty studies were included. The meta-analysis used the DerSimonian–Laird continuous random-effects method to calculate the pooled estimated means and 95% confidence interval. The estimated mean injury incidence rate for men was 108.5/1000 player-hours (95% CI: 85.9–131.0) and 76.1/1000 player-hours (95% CI: 48.7–103.5) for women. The estimated mean severity for men was 33.9 days (95% CI: 20.7–47.0) and 44.2 days (95% CI: 32.1–56.3) for women. Significantly more match injuries occurred in the second half of matches, were acute, located at the lower limb, diagnosed as joint/ligament, and resulted from being tackled. Fatigue, player fitness, and previous injuries were associated with an increased risk of injury. There were no statistically significant differences between women's and men's injury profiles. However, the inherent cultural and gendered factors which divide the two sports should not be ignored. The findings from this review will help pave the way forward beyond the foundational stages of injury prevention research in rugby-7s.</p

High Sport Specialization Is Associated With More Musculoskeletal Injuries in Canadian High School Students

Objective: To describe levels of sport specialization in Canadian high school students and investigate whether sport specialization and/or sport participation volume is associated with the history of musculoskeletal injury and/or concussion.Design: Cross-sectional study.Setting: High schools, Alberta, Canada.Participants: High school students (14-19 years) participating in various sports.Independent Variables: Level of sport specialization (high, moderate, low) and sport participation volume (hours per week and months per year).Main Outcome Measures: Twelve-month injury history (musculoskeletal and concussion).Results: Of the 1504 students who completed the survey, 31% were categorized as highly specialized (7.5% before the age of 12 years). Using multivariable, negative, binomial regression (adjusted for sex, age, total yearly training hours, and clustering by school), highly specialized students had a significantly higher musculoskeletal injury rate [incidence rate ratio (IRR) = 1.36, 95% confidence interval (CI), 1.07-1.73] but not lower extremity injury or concussion rate, compared with low specialization students. Participating in one sport for more than 8 months of the year significantly increased the musculoskeletal injury rate (IRR = 1.27, 95% CI, 1.02-1.58). Increased training hours significantly increased the musculoskeletal injury rate (IRR = 1.18, 95% CI, 1.13-1.25), lower extremity injury rate (IRR = 1.16, 95% CI, 1.09-1.24), and concussion rate (IRR = 1.31, 95% CI, 1.24-1.39).Conclusions: Approximately one-third of Canadian high school students playing sports were categorized as highly specialized. The musculoskeletal injury rate was higher for high sport specialization students compared with low sport specialization students. Musculoskeletal injuries and concussion were also more common in students who train more and spend greater than 8 months per year in one sport

It takes two to tango:High Rates of Injury and Concussion in Ball Carriers and Tacklers in High School Boys' Rugby

Objective: To examine injury and concussion rates, mechanisms, locations, and types of injury in Canadian high school male rugby.Design:Prospective cohort study.Setting:High school male rugby.Participants:A total of 429 high school players (2018: n = 225, 2019: n = 256) were recruited from 12 teams in 7 schools in Calgary, Canada.Interventions: None.Main Outcome Measures: Injury surveillance included baseline questionnaires, weekly exposure, and injury reports. Injuries included those requiring medical attention, resulted in time loss and/or inability to complete a session. Concussion was defined as per the fifth Consensus on Concussion in Sport, and all players with a suspected concussion were referred to a study sport medicine physician.Results: A total of 134 injuries were captured, leading to an injury incidence rate (IR) of 57.9/1000 hours [95% confidence intervals (CIs): 45.4-73.8]. Median time loss was 6 days (range: 0-90). Injuries to the head were the most common (40%), followed by shoulder (12%) and ankle (10%). The concussion IR was 22.0/1000 hours (95% CIs: 15.9-30.4), which was the most common injury type (38%), followed by sprain (20%) and strain (15%). Sixty-five percent of injuries occurred in the tackle (ball carrier 35%, tackler 30%) and 76% of concussions (ball carrier 41%, tackler 35%).Conclusions: The rate of injury and concussion in Canadian youth high school male rugby is high, with tackle-related injuries and concussions the most common. Given this, there is a critical need for implementation of prevention strategies, in particular targeting concussion and the tackle event (eg, neuromuscular, tackle training, and law changes).</p

It takes two to tango:High Rates of Injury and Concussion in Ball Carriers and Tacklers in High School Boys' Rugby

Objective: To examine injury and concussion rates, mechanisms, locations, and types of injury in Canadian high school male rugby.Design:Prospective cohort study.Setting:High school male rugby.Participants:A total of 429 high school players (2018: n = 225, 2019: n = 256) were recruited from 12 teams in 7 schools in Calgary, Canada.Interventions: None.Main Outcome Measures: Injury surveillance included baseline questionnaires, weekly exposure, and injury reports. Injuries included those requiring medical attention, resulted in time loss and/or inability to complete a session. Concussion was defined as per the fifth Consensus on Concussion in Sport, and all players with a suspected concussion were referred to a study sport medicine physician.Results: A total of 134 injuries were captured, leading to an injury incidence rate (IR) of 57.9/1000 hours [95% confidence intervals (CIs): 45.4-73.8]. Median time loss was 6 days (range: 0-90). Injuries to the head were the most common (40%), followed by shoulder (12%) and ankle (10%). The concussion IR was 22.0/1000 hours (95% CIs: 15.9-30.4), which was the most common injury type (38%), followed by sprain (20%) and strain (15%). Sixty-five percent of injuries occurred in the tackle (ball carrier 35%, tackler 30%) and 76% of concussions (ball carrier 41%, tackler 35%).Conclusions: The rate of injury and concussion in Canadian youth high school male rugby is high, with tackle-related injuries and concussions the most common. Given this, there is a critical need for implementation of prevention strategies, in particular targeting concussion and the tackle event (eg, neuromuscular, tackle training, and law changes).</p

Shoulder Check:Investigating Shoulder Injury Rates, Types, Severity, Mechanisms, and Risk Factors in Canadian Youth Ice Hockey

Objective: To describe shoulder-related injury rates, types, severity, mechanisms, and risk factors in youth ice hockey players during games and practices. Study Design: Secondary analysis of data from a 5-year prospective cohort study Safeto-Play (2013-2018). Subjects: Overall, 4419 individual players (representing 6585 player-seasons; 3806 males: 613 females) participated. During this period, 118 primary shoulder-related game injuries and 12 practice injuries were reported. Outcome Measures: Injury surveillance data was collected from 2013-2018 (time-loss or medical attention injuries). Descriptive statistics were calculated, and injury rates with 95% CI were estimated using Poisson regression. An exploratory multivariable mixed-effects Poisson regression model (clustering by team and offset by exposure hours) examined risk factors. Results: The shoulder injury rate was 0.70 injuries/1000 game-hours (95% CI 0.371.33) and 0.07 injuries/1000 practice-hours (95% CI 0.04-0.12). Two-thirds of game injuries (n=79, 69%) resulted in &gt;8 days of time-loss, and more than one-third (n=44, 39%) resulted in &gt;28 days of time-loss. An 82% lower rate of shoulder injury was associated with policy prohibiting body checking compared to leagues allowing body checking [IRR=0.18 (95% CI 0.10-0.32)]. A higher shoulder injury rate was seen for those who reported any injury in the last 12-months compared to those with no history [IRR=2.32 (95% CI 1.57-3.41)]. Conclusions: Most shoulder injuries resulted in more than one week of time-loss. Risk factors for shoulder injury included participation in a body checking league and history of injury in the previous 12 months. Further study of prevention strategies specific to the shoulder may merit further consideration in ice hockey