Effects of States’ Laws on Youth Physical Activity Participation and Obesity Prevalence

The alarming prevalence of obesity and lack of physical activity among adolescents led to immediate policy action to address these concerns. Accordingly, many states introduced and enacted their own legislation to encourage physical activity in schools. Few studies have explored the effectiveness of the new legislation, however, especially at the state level. To answer the fundamental question of whether policy is effective and to describe the varying effects of state obesity policies, this study analyzed the Youth Risk Behavior Surveillance System from 2007 to 2017. Using the difference-in-differences method, this study found that legislative efforts to encourage physical activity had a significant and substantial effect on enhancing physical-activity participation and reducing adolescent obesity; however, subgroup analyses revealed that the effect was concentrated on female and white adolescents only. Additionally, the subsequent sensitivity analysis revealed that since 2015, when national attention started to divert to new health concerns (opioid abuse, for example), physical activity levels pulled back to 2009 levels. Rates of obesity and overweight have been on a sharp rise again since 2015. Lawmakers should reconsider changes in the law merging physical environments with digital environments, particularly for members of Generation Alpha, who will have ever more enticements for screen time

Crystal Structure of Human Mre11: Understanding Tumorigenic Mutations

SummaryMre11 plays an important role in repairing damaged DNA by cleaving broken ends and by providing a platform for other DNA repair proteins. Various Mre11 mutations have been identified in several types of cancer. We have determined the crystal structure of the human Mre11 core (hMre11), which contains the nuclease and capping domains. hMre11 dimerizes through the interfaces between loop β3-α3 from one Mre11 and loop β4-β5 from another Mre11, and between loop α2-β3 from one Mre11 and helices α2 and α3 from another Mre11, and assembles into a completely different dimeric architecture compared with bacterial or archaeal Mre11 homologs. Nbs1 binds to the region containing loop α2-β3 which participates in dimerization. The hMre11 structure in conjunction with biochemical analyses reveals that many tumorigenic mutations are primarily associated with Nbs1 binding and partly with nuclease activities, providing a framework for understanding how mutations inactivate Mre11

Crystal structure of the NurA–dAMP–Mn2+ complex

Generation of the 3′ overhang is a critical event during homologous recombination (HR) repair of DNA double strand breaks. A 5′–3′ nuclease, NurA, plays an important role in generating 3′ single-stranded DNA during archaeal HR, together with Mre11–Rad50 and HerA. We have determined the crystal structures of apo- and dAMP-Mn2+-bound NurA from Pyrococcus furiousus (Pf NurA) to provide the basis for its cleavage mechanism. Pf NurA forms a pyramid-shaped dimer containing a large central channel on one side, which becomes narrower towards the peak of the pyramid. The structure contains a PIWI domain with high similarity to argonaute, endoV nuclease and RNase H. The two active sites, each of which contains Mn2+ ion(s) and dAMP, are at the corners of the elliptical channel near the flat face of the dimer. The 3′ OH group of the ribose ring is directed toward the channel entrance, explaining the 5′–3′ nuclease activity of Pf NurA. We provide a DNA binding and cleavage model for Pf NurA

THE EFFECTS OF WEARING ROLLER SHOES ON MUSCLE ACTIVITY IN THE LOWER EXTREMITY DURING WALKING

Roller shoes have become increasingly popular among children and its features of retractable wheels which allow the user to walk or roll without changing the footwear. Maintaining balance during forward walking with roller shoes is not an easy task. To prevent falling backward, the user needs to lock the knees and tighten the ankles and thighs while the upper body is slightly leaning forward. Constant walking with roller shoes forces the user to walk in a manner much different from normal gait. Prolonged exposure to un-natural stresses on human body forces our body to evolve by strengthening those incorrect and temporary functions (Clement et al., 1981). For children, the chronic stress may lead to serious injuries in the lower extremity later in life. If any potential of injury exists in a movement it is critical to examine the associated muscle activity that may lead to injury. To the best of our knowledge, the effects of wearing roller shoes on muscle activity in the lower extremity have rarely been studied, especially in the youth population. Thus, the purpose of this study was to compare muscle activity in the lower extremity during walking wearing jogging and roller shoes

TIBIO-FEMORAL JOINT FORCES DURING THE LANDING PHASE OF DIFFERENT TYPES OF VERTICAL JUMP

The purpose of this study was to compare the tibio-femoral contact forces during the landing phases of 8 different types of vertical jump (squat, countermovement, hop approach and drop jumps each with and without the use of arms). Data were collected from eight males and eight females. Two S-VHS camcorders and a force platform were used to obtain the 3-D kinematics and kinetics of the knee joint. Activities of selected muscles spanning the knee joint were monitored using surface electromyographic (EMG) techniques. The EMG-assisted optimization model was used to estimate the tibio-femoral joint forces. The peak compressive contact forces ranged from 3-5 body weight (SW) and from 2.5-3.7 SW for the males and females, respectively. These loads seldom fell within the range that is considered to be damaging to the cartilage at the knee

Ticks Collected from Selected Mammalian Hosts Surveyed in the Republic of Korea During 2008-2009

A tick survey was conducted to determine the relative abundance and distribution of ticks associated with selected mammals in the Republic of Korea (ROK) during 2008-2009. A total of 918 ticks were collected from 76 mammals (6 families, 9 species) captured at 6 provinces and 3 Metropolitan Cities in ROK. Haemaphysalis longicornis (54.4%) was the most frequently collected tick, followed by Haemaphysalis flava (28.5%), Ixodes nipponensis (7.6%), Ixodes pomerantzevi (4.8%), Ixodes persulcatus (4.6%), and Haemaphysalis japonica (0.1%). Adults (57.0%) and nymphs (28.7%) of Ixodes and Haemaphysalis spp. were collected most frequently from medium or large mammals in this survey, while few larvae (14.3%) were collected. Hydropotes inermis was the most frequently captured mammal (52.6%), with a 16.4 tick index and 5 of 6 species of ticks collected during this survey. H. longicornis (69.7%) was the predominant tick collected from H. inermis, followed by H. flava (22.2%), I. persulcatus (6.1%), I. nipponensis (1.8%), and H. japonica (0.2%)

THE EFFECTS OF WEARING SPANDEX WEAR WITH COMPRESSION BAND ON MUSCLE ACTIVITY DURING A GOLF SWING

The purpose of this study was to determine how spandex wear with compressive band affects muscle activities during a golf swing. This study showed that average and maximum nEMG (normalized EMG) values of left AO (external abdominal oblique) were less in EG (experimental group) compared with CG (control group) during back swing, whereas those of left PM (pectoralis major) in EG were greater than CG. It is more likely that EG performed effectively golf swing without excess muscle activity. Thus, the spandex wear with compressive band played an important role in improving swing performance with injury prevention. This has led to suggestions of the need for further kinetic and kinematic analyses to evaluate its function

KINEMATIC ANALYSIS OF THE WOMEN’S JAVELIN THROW AT THE IAAF WORLD CHAMPIONSHIPS, DAEGU 2011

The purpose of this study was to analyze the kinematic variables for the women's javelin throw at the IAAF World Championships, Daegu 2011. Three-dimensional motion analyses of the eight players who qualified for the final round were carried out to obtain the data. The results showed that average release, attitude, and attack angles were 38.0±2.0°, 40.4±4.3°, and 3.7±1.1°, respectively. At the release, the average inclination angle of the trunk, upper arm, forearm were 60.8±8.3°, 47.3±10.1°, and 62.6±10.6°, respectively. Moreover, the release velocity and the release height results averaged 25.60±1.16 m/s and 1.86±0.05 m. The crossover phase and delivery phase had average distances of 1.88±0.31 m and 1.53±0.21 m. After release, the average distance between the landing foot and the foul line was 1.72±0.63 m