The End is Not the Injury: Posttraumatic Growth After Sport Injuries

This quantitative study explored whether serious injuries in varsity high school or collegiate athletes could produce Posttraumatic Growth (PTG). The impact of injury (season- or career-ending) and an athlete’s highest level of competition played (varsity high school or collegiate) were examined on five elements on the 2-item Posttraumatic Growth Inventory (PTGI): (1) relating to others, (2) new possibilities, (3) personal strength, (4) spiritual change, and (5) appreciation of life. This study provides evidence that sport level does not impact an athlete’s ability to produce PTG and bring awareness to trauma and the role PTG can have in an athlete’s life

Natural variation in teosinte at the domestication locus teosinte branched1 (tb1)

The teosinte branched1(tb1) gene is a major QTL controlling branching differences between maize and its wild progenitor, teosinte. The insertion of a transposable element (Hopscotch) upstream of tb1 is known to enhance the gene’s expression, causing reduced tillering in maize. Observations of the maize tb1 allele in teosinte and estimates of an insertion age of theHopscotch that predates domestication led us to investigate its prevalence and potential role in teosinte. We assessed the prevalence of the Hopscotchelement across an Americas-wide sample of 837 maize and teosinte individuals using a co-dominant PCR assay. Additionally, we calculated population genetic summaries using sequence data from a subset of individuals from four teosinte populations and collected phenotypic data using seed from a single teosinte population where Hopscotch was found segregating at high frequency. Genotyping results indicate the Hopscotchelement is found in a number of teosinte populations and linkage disequilibrium near tb1 does not support recent introgression from maize. Population genetic signatures are consistent with selection on the tb1 locus, revealing a potential ecological role, but a greenhouse experiment does not detect a strong association between the Hopscotch and tillering in teosinte. Our findings suggest the role of Hopscotch differs between maize and teosinte. Future work should assess tb1 expression levels in teosinte with and without the Hopscotch and more comprehensively phenotype teosinte to assess the ecological significance of the Hopscotch insertion and, more broadly, the tb1 locus in teosinte

Flue-cured tobacco and Cl rates : implications on yield, quality, and nutrient concentration

The increase in flue-cured tobacco (Nicotiana tabacumL.) yields in recent decadesdue to genetic improvements of new cultivars and management technologies mayincrease the plant demand for Cl, and the increased dry mass may dilute Cl concentra-tion, thereby reducing negative effects. This study evaluated the effect of increasingdoses of Cl on tobacco production, quality, and chemical composition of leaves, infour growing environments located at research stations where flue-cured tobacco isproduced in North Carolina. The treatments consisted of 11 rates of Cl (0, 11, 22,34, 45, 56, 67, 78, 90, 101, and 112 kg ha−1) in each growing environment, with fourreplications in a randomized complete block design. The yield and visual quality,total alkaloids, and reducing sugars concentrations of cured leaf were determined.In addition, the concentration of selected nutrients (N, P, K, Ca, Mg, S, and Cl) andnitrate (NO3−) in tobacco leaves was measured in five different periods. Rates of Clup to 112 kg ha−1did not reduce the productivity or quality of flue-cured tobaccoin any environment. The Cl rate required to reach the threshold of 1.0% Cl contentin cured leaf was site-specific, being surpassed even in the control treatment at onelocation, or with Cl rates higher than 34 and 90 kg ha−1in two environments. Inone environment, the Cl rates increased tobacco yield, probably due the direct effectof Cl as a nutrient. Although the increasing Cl rates increased the reducing sugarsconcentration, visual quality was not attenuated

Perturbing microwave beams by plasma density fluctuations

The propagation of microwaves across a turbulent plasma density layer is investigated with full-wave simulations. To properly represent a fusion edge-plasma, drift-wave turbulence is considered based on the Hasegawa-Wakatani model. Scattering and broadening of a microwave beam whose amplitude distribution is of Gaussian shape is studied in detail as a function of certain turbulence properties. Parameters leading to the strongest deterioration of the microwave beam are identified and implications for existing experiments are given

Physiological Differences Between Low Versus High Skeletal Muscle Hypertrophic Responders to Resistance Exercise Training: Current Perspectives and Future Research Directions

Numerous reports suggest there are low and high skeletal muscle hypertrophic responders following weeks to months of structured resistance exercise training (referred to as low and high responders herein). Specifically, divergent alterations in muscle fiber cross sectional area (fCSA), vastus lateralis thickness, and whole body lean tissue mass have been shown to occur in high versus low responders. Differential responses in ribosome biogenesis and subsequent protein synthetic rates during training seemingly explain some of this individual variation in humans, and mechanistic in vitro and rodent studies provide further evidence that ribosome biogenesis is critical for muscle hypertrophy. High responders may experience a greater increase in satellite cell proliferation during training versus low responders. This phenomenon could serve to maintain an adequate myonuclear domain size or assist in extracellular remodeling to support myofiber growth. High responders may also express a muscle microRNA profile during training that enhances insulin-like growth factor-1 (IGF-1) mRNA expression, although more studies are needed to better validate this mechanism. Higher intramuscular androgen receptor protein content has been reported in high versus low responders following training, and this mechanism may enhance the hypertrophic effects of testosterone during training. While high responders likely possess “good genetics,” such evidence has been confined to single gene candidates which typically share marginal variance with hypertrophic outcomes following training (e.g., different myostatin and IGF-1 alleles). Limited evidence also suggests pre-training muscle fiber type composition and self-reported dietary habits (e.g., calorie and protein intake) do not differ between high versus low responders. Only a handful of studies have examined muscle biomarkers that are differentially expressed between low versus high responders. Thus, other molecular and physiological variables which could potentially affect the skeletal muscle hypertrophic response to resistance exercise training are also discussed including rDNA copy number, extracellular matrix and connective tissue properties, the inflammatory response to training, and mitochondrial as well as vascular characteristics

LAT1 Protein Content Increases Following 12 Weeks of Resistance Exercise Training in Human Skeletal Muscle

Introduction: Amino acid transporters are essential for cellular amino acid transport and promoting protein synthesis. While previous literature has demonstrated the association of amino acid transporters and protein synthesis following acute resistance exercise and amino acid supplementation, the chronic effect of resistance exercise and supplementation on amino acid transporters is unknown. The purpose herein was to determine if amino acid transporters and amino acid metabolic enzymes were related to skeletal muscle hypertrophy following resistance exercise training with different nutritional supplementation strategies. Methods: 43 college-aged males were separated into a maltodextrin placebo (PLA, n = 12), leucine (LEU, n = 14), or whey protein concentrate (WPC, n = 17) group and underwent 12 weeks of total-body resistance exercise training. Each group\u27s supplement was standardized for total energy and fat, and LEU and WPC supplements were standardized for total leucine (6 g/d). Skeletal muscle biopsies were obtained prior to training and ~72 h following each subject\u27s last training session. Results: All groups increased type I and II fiber cross-sectional area (fCSA) following training (p \u3c 0.050). LAT1 protein increased following training (p \u3c 0.001) and increased more in PLA than LEU and WPC (p \u3c 0.050). BCKDHα protein increased and ATF4 protein decreased following training (p \u3c 0.001). Immunohistochemistry indicated total LAT1/fiber, but not membrane LAT1/fiber, increased with training (p = 0.003). Utilizing all groups, the change in ATF4 protein, but no other marker, trended to correlate with the change in fCSA (r = 0.314; p = 0.055); however, when regression analysis was used to delineate groups, the change in ATF4 protein best predicted the change in fCSA only in LEU (r2 = 0.322; p = 0.043). In C2C12 myoblasts, LAT1 protein overexpression caused a paradoxical decrease in protein synthesis levels (p = 0.002) and decrease in BCKDHα protein (p = 0.001). Conclusions: Amino acid transporters and metabolic enzymes are affected by resistance exercise training, but do not appear to dictate muscle fiber hypertrophy. In fact, overexpression of LAT1 in vitro decreased protein synthesis

Impact of Oral Meloxicam on Circulating Physiological Biomarkers of Stress and Inflammation in Beef Steers After Long Distance Transportation

We hypothesized that meloxicam administration to beef steers before shipping may be effective at reducing the impact of transportation on stress biomarkers. Circulating physiological biomarkers of stress were analyzed in a transportation trial between a meloxicam treatment group and a placebo treatment group. There were significant differences in stress biomarkers between treatment groups following transport. This suggests that there may be practical benefits for the use of long-acting non-steroidal anti-inflammatory drugs (NSAIDs), specifically meloxicam, to mitigate the negative effect of transport on cattle physiology