Intersession Reliability and Within-Session Stability of a Novel Perception-Action Coupling Task

BACKGROUND: The perception-action coupling task (PACT) was designed as a more ecologically valid measure of alertness/reaction times compared to currently used measures by aerospace researchers. The purpose of this study was to assess the reliability, within-subject variability, and systematic bias associated with the PACT. METHODS: There were 16 subjects (men/women = 9/7; age = 27.8 +/- 3.6 yr) who completed 4 identical testing sessions. The PACT requires subjects to make judgements on whether a virtual ball could fit into an aperture. For each session, subjects completed nine cycles of the PACT, with each cycle lasting 5 min. Judgement accuracy and reaction time parameters were calculated for each cycle. Systematic bias was assessed with repeated-measures ANOVA, reliability with intraclass correlation coefficients (ICC), and within-subject variability with coefficients of variation (CVTE). RESULTS: Initiation time (Mean = 0.1065 s) showed the largest systematic bias, requiring the elimination of three cycles to reduce bias, with all other variables requiring, at the most, one. All variables showed acceptable reliability (ICC > 0.70) and within-subject variability (CVTE <20%) with only one cycle after elimination of the first three cycles. CONCLUSIONS: With a three-cycle familiarization period, the PACT was found to be reliable and stable

Impact of Increased Load Carriage Magnitude on the Dynamic Postural Stability of Men and Women

The impact of load carriage on dynamic postural stability affects the survivability of the Warfighter by influencing performance capabilities and injury incidence. Further, sex may interact with the relationship between load carriage and dynamic postural stability to further compromise survivability. PURPOSE: To investigate the effect of load carriage magnitude on dynamic postural stability of men and women and its relationship to jumping ability. METHODS: 32 subjects (16 men, 16 women) were investigated for maximum jump height and dynamic postural stability. Dynamic postural stability was assessed by subjects jumping a horizontal distance of 40% their height over a 30cm hurdle, landing on one leg on a force plate (sample rate = 1200 Hz). 3 trials were completed for 3 load conditions: +0, +20 and +30% body weight (BW). Dynamic postural stability was determined from ground reaction force data during landings, by calculation of the dynamic postural stability index (DPSI). Maximum jump height was assessed by subjects performing 3 countermovement jumps (sample rate = 1000 Hz). Two-way repeated measures ANOVA were used to compare mean DPSI scores between sexes and conditions (α = 0.05). Pearson’s Correlation Coefficients were used to determine the relationship between jump height and change in DPSI scores between conditions (α = 0.05). RESULTS: Load condition significantly affected DPSI (F = 100.304, p = 0.001). DPSI scores increased between the 0% (0.359 ± 0.041), 20% (0.396 ± 0.034) and 30% (0.420 ± 0.028) BW load conditions. No significant effect of sex on DPSI was found (F = 0.131). No significant sex by load interaction on DPSI was found (F = 0.393). No significant correlations were found between jump height and change in DPSI scores between conditions. CONCLUSION: Increased load was found to negatively affect dynamic postural stability, most likely as a result of modifying the demands of the task. Therefore, the dynamic postural stability of men and women changes comparably in response to increased load carriage magnitude. Future research should focus on the effects of load on dynamic postural stability under higher loads and during more military-specific tasks

LOAD CARRIAGE ALTERS TIBIOFEMORAL KINEMATICS DURING SLOW JOGGING IN ADULT MEN AND WOMEN

The purpose of this investigation was to determine the effects of load carriage on tibiofemoral kinematics during running. Nineteen healthy, recreationally active adults completed dynamic biplane radiography trials of the dominant limb knee with no load (BW), and an additional 55% of body weight (+55%BW) while running 10% above gait transition velocity. A volumetric model-based tracking technique was utilized to derive medial translation excursion, proximal (inferior-superior) translation excursion, anterior translation excursion, flexion, internal rotation and abduction. At heel strike, running with +55%BW exhibited a more flexed knee compared to BW. However, BW exhibited more proximal translation excursion compared to +55%BW. By contrast, +55%BW had greater anterior translation excursion compared to BW. There were no significant differences between BW and +55%BW for medial translation excursion, internal rotation angle/excursion or abduction angle/excursion The greater knee flexion angle at heel strike for +55%BW may serve as a mechanism to better attenuate the greater impact force via eccentric muscle action. However, reduced proximal translation excursion during +55%BW could suggest greater loading of the soft tissues

Efficacy, safety, tolerability and population pharmacokinetics of tedizolid, a novel antibiotic, in Latino patients with acute bacterial skin and skin structure infections

AbstractAcute bacterial skin and skin structure infections are caused mainly by Gram-positive bacteria which are often treated with intravenous vancomycin, daptomycin, or linezolid, with potential step down to oral linezolid for outpatients. Tedizolid phosphate 200mg once daily treatment for six days demonstrated non-inferior efficacy, with a favourable safety profile, compared with linezolid 600mg twice daily treatment for 10 days in the Phase 3 ESTABLISH-1 and -2 trials. The objective of the current post-hoc analysis of the integrated dataset of ESTABLISH-1 and -2 was to evaluate the efficacy and safety of tedizolid (N=182) vs linezolid (N=171) in patients of Latino origin enrolled into these trials. The baseline demographic characteristics of Latino patients were similar between the two treatment groups. Tedizolid demonstrated comparable efficacy to linezolid at 48–72h in the intent-to-treat population (tedizolid: 80.2% vs linezolid: 81.9%). Sustained clinical success rates were comparable between tedizolid- and linezolid-treated Latino patients at end-of-therapy (tedizolid: 86.8% vs linezolid: 88.9%). Tedizolid phosphate treatment was well tolerated by Latino patients in the safety population with lower abnormal platelet counts at end-of-therapy (tedizolid: 3.4% vs linezolid: 11.3%, p=0.0120) and lower incidence of gastrointestinal adverse events (tedizolid: 16.5% vs linezolid: 23.5%). Population pharmacokinetic analysis suggested that estimated tedizolid exposure measures in Latino patients vs non-Latino patients were similar. These findings demonstrate that tedizolid phosphate 200mg, once daily treatment for six days was efficacious and well tolerated by patients of Latino origin, without warranting dose adjustment

The Effects of a Korean Ginseng, GINST15, on Hypo-Pituitary-Adrenal and Oxidative Activity Induced by Intense Work Stress

The effect of GINST15, an enzyme fermented ginseng supplement, on hormonal and inflammatory responses to physical stress in humans is unknown. The purpose of this investigation was to examine the constitutive and stress-induced effects of GINST15 supplement on hypo-pituitary-adrenal (HPA) and antioxidant activity in addition to muscle damage. Ten women (age: 38.7 ± 7.8 years; height: 163.81 ± 4.4 cm; body mass 76.0 ± 11.6 kg) and nine men (age: 41.2. ± 9.7 years; height: 177.4 ± 5.3 cm; body mass: 88.5 ± 5.0 kg) participated in a double-blinded, placebo-controlled, counterbalanced within-group study. Participants completed three 14-day treatment cycles with different doses (high: 960 mg; low: 160 mg; placebo: 0 mg) separated by a 1-week washout period. At the end of treatment, physical stress was imposed with intense resistance exercise work stress. Participants provided blood at rest and various time points after exercise (immediately [IP], 30 min [30], 60 min [60], 24 h [+24HR]). Cortisol (CORT), superoxide dismutase (SOD), total glutathione, nonspecific antioxidant activity, total antioxidant power (TAP), and creatine kinase were measured. GINST15 supplementation produced stress-inducible dose-dependent reductions in circulating cortisol and increased enzymatic and nonspecific antioxidant activity. Twenty-four hours after intense exercise, a high dose GINST15, a bioactive ginsenoside metabolite, significantly reduces muscle damage and HPA responses to physical stress in humans; these effects may result from increased antioxidant expression

Bioactive growth hormone in older men and women: Its relationship to immune markers and healthspan

Objective: The consequences of age-related decline in the somatotropic axis of humans are complex and remain largely unresolved. We tested the hypothesis that hGH measurements of plasma by bioassay vs immunoassay from samples obtained from free-living, elderly individuals would reveal a dichotomy in GH activities that are correlated with the functional status of the donors, i.e. their healthspan. Design: Forty-one men and women of advanced age (men: N=16, age, 80.5±6.5years; height, 173.1±6.9cm; body mass, 81.8±13.0kg) and (women: N=25, age, 80.7±7.2years; height, 157.7±6.0cm; body mass, 68.8±17kg), were recruited for a cross-sectional study. Participants filled out PROMIS (Patient-Reported Outcomes Measurement Information System, U. S. Department of Health and Human Services) scales, undertook physical performance tests and had fasted blood samples obtained at rest for measurement of hormonal and immunology biomarkers. Results: When measured by the well-established rat tibial line GH bioassay, one half of the plasma samples (n=20) contained bioassayable GH (bGH), but the other half (n=21) failed to mount increases in tibial plate width above saline injected controls. This difference did not correlate with the age, sex or physical functionality of the plasma donor. It also did not correlate with hGH concentrations measured by immunoassay. In those cases in which bGH was detected, various hierarchical regression models predicted that GHRH, c-peptide, VEGF, NPY, IL-4 and T-regulatory lymphocytes were associated with the difference and predicted bGH. Conclusion: Results from this study suggest that the actions of bGH at the cellular level may be modified by other factors and that this may explain the lack of correlations observed in this study

Relationships of Physical Performance Tests to Military-relevant Tasks in Women

Purpose: This investigation sought to determine the most predictive measures of performance on a repetitive box lifting task (RBLT) and load bearing task (LBT) among 123 women (aged 23±4 years, height 165±7 cm, body mass 64±10 kg). Methods: To determine the relationship of various predictors to performance on the RBLT and LBT, multiple regression analysis was conducted on body mass, height, leg cross-sectional area, upper and lower body muscular strength, lower body explosive power, upper and lower body local muscular endurance, and aerobic capacity. Results: The mean±SD (range) number of repetitions for the RBLT was 86±23 (20-159). The mean±SD (range) time to complete the LBT was 2,054±340 seconds (1,307-3,447). The following equations were generated: RBLT (number of repetitions)=57.4 + 0.2(peak jump power) + 0.4(number of pushups in 2 minutes) + 0.15(number of repetitions during the squat endurance test) + 1.39(one repetition maximal strength boxlift (kg)) – 0.04(2-mile run time (2MR) in seconds), R=0.81; standard error of the estimate (SEE)=14; LBT (in seconds)=1,831 – 4.28(number of repetitions during the squat endurance test) + 0.95(2MR in seconds) – 13.4(body mass), R=0.73; SEE=232. Conclusions: We found that the 2MR and squat endurance test were signifi cant predictive factors for performance on both load carriage tasks. These data also imply that women’s performance in combat-related tasks can be improved with training that targets muscular strength, power, and local muscular endurance in addition to aerobic capacity

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead