The aims of the current study were to (a) determine between-session reliability of peak force during the Nordic hamstring exercise (NHE) in professional soccer players during the preseason and (b) determine the subsequent magnitude and direction of peak force asymmetry from the NHE between all test sessions. The NHE was used as a weekly monitoring tool in 14 professional soccer players, throughout a 6-week pre-season period to record peak force from the NordBord device (in Newtons-N) across an average of 6 repetitions for the dominant and nondominant limbs. The first 2 weeks were used as familiarization sessions, with 4 data collection sessions thereafter. When considering relative reliability, intraclass correlation coefficients (ICCs) showed moderate levels of between-session reliability across the 4 weeks on both limbs (dominant 5 0.54-0.73 and nondominant 5 0.68-0.73) and for the sum total (0.69-0.73). For absolute reliability, both limbs showed coefficient of variation (CV) values ,10% across all 4 weeks, with the exception of the dominant limb between sessions 1-2 (10.06%). When determining systematic bias, no meaningful changes were evident in peak force on either limb (g 5 20.59 to 0.40) or for the magnitude of asymmetry (g 5 20.24 to 0.35). However, when assessing consistency in the direction of asymmetry, levels of agreement ranged from 43 to 57% across the data collection period, indicating substantial variation in the superior performing limb from session to session. The findings from this study indicate that 2 familiarization sessions is enough to elicit reliable peak force data during the NHE in professional soccer players during preseason, despite a very small learning effect across the testing period.

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Airborne dust can alter ecosystem productivity and biogeochemical cycling by enhancing atmospheric nutrient and pollutant deposition. Wet dust deposition (dust-in-rain) is less frequently quantified than dry deposition but represents a potentially significant flux to ecosystems. We quantified dust-in-rain event frequency, dust influence on rainwater ionic and elemental composition, and wet dissolved and particulate deposition during weeks affected by dust-in-rain and all other weeks (background samples) at two sites across Texas (one arid, Guadalupe Mountains, and one humid, Gulf coastal prairie) during the centennialscale 2012 drought. Although dust-in-rain was sporadic, a clear dust signature was evident in rainwater. Compared to background samples, crustal species (Fe and Mn) were more prevalent than anthropogenic species (Cu and Zn) in dust-in-rain. Volume-weighted mean rainwater concentrations of K + , Na + , and Cl À and of all particulate elements were also significantly greater in dust-in-rain than in background samples. In the Guadalupe Mountains, West Texas, dust-in-rain contributed nearly 50% of annual wet dissolved Na + and Cl À and 22-35% of dissolved Ca 2+ , Mg 2+ , K + , and PO 4 3À deposition. In the Gulf coastal prairie, East Texas, dust-in-rain delivered 19%, 13%, and 9% of annual wet dissolved PO 4 3À , Ca 2+ , and K + deposition, respectively. A major proportion of annual wet particulate deposition (>56% in Guadalupe Mountains and~30% in Gulf coastal prairie) similarly occurred with dust-in-rain. Our findings show that infrequent dust-in-rain events constitute an important but overlooked pathway for elemental flux to ecosystems in arid source and humid receptor sites during severe drought. Quantifying these fluxes is crucial to determine dust impacts on ecosystem processes.Plain Language Summary Blowing soil dust is a frequent phenomenon in Texas caused by dry conditions, strong winds, and bare soil. Across the U.S. Southwest, severe drought and land use change are projected to increase in the future, contributing to more frequent and intense dust storms and eventually dry dust fallout or dust washout from the atmosphere with rain (dust-in-rain). Dust-in-rain contains dissolved substances that act as nutrients to plants and ecosystems, as well as others that can be toxic pollutants. Dust-in-rain also contains particles that contribute to soil formation and fertility. How will warmer, drier, Dust Bowl-like conditions affect raining dust events? To answer this question, we examined rainwater samples collected by the National Atmospheric Deposition Program at two Texas sites (one arid, Guadalupe Mountains, and one humid, Gulf coastal prairie) during 2012, a year of extreme drought (and dust) in Texas. We determined the number of dust-in-rain events at each site, analyzed concentrations of diverse substances (some nutrients and some pollutants) in rainwater, and quantified the annual proportion of nutrients and pollutants delivered to the sites in rain during weeks affected by dust. Although dust-...

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