148,202 research outputs found
Developing young children's understanding of place-value using multiplication and quotitive division
No full textThis paper focuses on selected findings from a study that explored the use of multiplication and division with 34 five- and six-year-old children from diverse cultural and linguistic backgrounds. The focus of instructional tasks was on working with groups of ten to support the understanding of place value. Findings from relevant assessment tasks and children’s work highlighted the importance of encouraging young children to move from unitary (counting by ones) to tens-structured thinking
Serum 25-hydroxy vitamin D and the risk of low muscle mass in young and middle-aged Korean adults
Full text linkObjective: Despite the known benefit of vitamin D in reducing sarcopenia risk in older adults, its effect against muscle loss in the young population is unknown. We aimed to examine the association of serum 25-hydroxy vitamin D [25(OH)D] level and its changes over time with the risk of incident low muscle mass (LMM) in young and middle-aged adults.Design: This study is a cohort study.Methods: The study included Korean adults (median age: 36.9 years) without LMM at baseline followed up for a median of 3.9 years (maximum: 7.3 years). LMM was defined as the appendicular skeletal muscle (ASM) mass by body weight (ASM/weight) of 1 s.d. below the sex-specific mean for the young reference group. Cox proportional hazard models were used to estimate hazard ratios (HRs) with 95% CIs.Results: Of the 192,908 individuals without LMM at baseline, 19,526 developed LMM. After adjusting for potential confounders, the multivariable-adjusted HRs (95% CIs) for incident LMM comparing 25(OH)D levels of 25-<50, 50-<75, and ≥75 nmol/L to 25(OH)D <25 nmol/L were 0.93 (0.90-0.97), 0.85 (0.81-0.89), and 0.77 (0.71-0.83), respectively. The inverse association of 25(OH)D with incident LMM was consistently observed in young (aged <40 years) and older individuals (aged ≥40 years). Individuals with increased 25(OH)D levels (<50-≥50 nmol/L) or persistently adequate 25(OH)D levels (≥50 nmol/L) between baseline and follow-up visit had a lower risk of incident LMM than those with persistently low 25(OH)D levels.Conclusions: Maintaining sufficient serum 25(OH)D could prevent unfavourable changes in muscle mass in both young and middle-aged Korean adults.</p
Match-Play Demands of Elite U17 Hurlers During Competitive Matches
Full text linkYoung, D, Mourot, L, Beato, M, and Coratella, G. Match-play demands of elite U17 hurlers during competitive matches. J Strength Cond Res XX(X): 000-000, 2019-The current study aimed to quantify the match-play workload in elite male under 17 hurlers, measuring the differences between the first and second halves and between positions. Global positioning system (10-Hz) and heart rate monitors were used to collect data from 76 players during 18 matches. Players' total distance (TD), relative distance (RD), high-speed running (HSR), the number and length of sprints, and the total sprint distance (TSD) was 6,483 ± 1,145 m, 108 ± 19 m·min, 583 ± 215 m, 18 ± 6, 15 ± 3 m, and 272 ± 77 m, respectively. Peak and mean heart rate were 194 ± 8 b·min and 167 ± 4 b·min, respectively. Decrements in TD (p < 0.001, effect size [ES] = 0.72), RD (p < 0.001, ES = 0.72), HSR (p < 0.001, ES = 0.55), the number of sprints (p < 0.001, ES = 0.57), mean length of sprint (p < 0.011, ES = 0.25), TSD (p < 0.001, ES = 0.69), mean heart rate (p < 0.001, ES = 0.35), and peak heart rate (p < 0.001, ES = 0.52) were found between halves. Largely-to-very largely greater TD, RD, and HSR were covered by midfielders, half-backs, and half-forwards compared with full-backs and full-forwards. No between-position difference was found in peak and mean heart rate. The current results are the first to highlight the differences in external and internal position-specific workload in elite male under 17 hurlers. Coaches need to consider the position-specific demands and between-half drop-off to prepare young hurlers appropriately to repeat the match-play performances of competition
R&D Drivers in Young Innovative Companies
Full text linkThis paper examines the determinants of young innovative companies' (YICs) R&D activities taking into account the autoregressive nature of innovation. Using a large longitudinal dataset comprising Spanish manufacturing firms over the period 1990-2008, we find that previous R&D experience is a fundamental determinant for mature and young firms, albeit to a smaller extent in the case of the YICs, suggesting that their innovation behaviour is less persistent and more erratic. Moreover, our results suggest that firm and market characteristics play a distinct role in boosting the innovation activity of firms of different age. In particular, while market concentration and the degree of product diversification are found to be important in fostering R&D activities in the sub-sample of mature firms only, YICs' spending on R&D appears to be more sensitive to demand-pull variables, suggesting the presence of credit constraints. These results have been obtained using a recently proposed dynamic type-2 tobit estimator, which accounts for individual effects and efficiently handles the initial conditions problem.R&D, innovation, Young Innovative Companies (YICs), dynamic type-2 tobit estimator
Radar Classification of the Antarctic Ice-Bed Interface: Version 2
No full textThis classified_bed data product represents the radar bed classification shown in Young et al., 2016. Values of 0 represent specularity content below 20%; values of 3.3 represent specularity content above 20% and energy 1 microsecond below the bed 15 dB lower than the bed echo, and values of 6.7 represent specularity content above 20% and energy 1 microsecond below the bed 15 dB within than the bed echo. Grids for specularity content and post bed echo are also available. Data is available as COARDS-compliant netCDF-4/HDF5 grids (.grd) and GeoTiffs (.tiff), both in EPSG 3031 (Antarctic Polar Stereographic) projection.
Data were gridded using GMT6.1 and the nnbathy natural neighbor interpolator. Cell size was 1 km, gaussian filter distance was 5 km, and mask radius was 2 km.
Browse images, with Bedmap3 (Pritchard et al., 2025) surface elevation contours and MEASURES phase derived surface velocities (Mouginot et al. 2019) are available for each dataset.
An interpretation of the values in the classified_bed product is that low values are rough bed, intermediate values are isotropic wet bed, and high values are anisotropic wet bed.
Version 1 includes data from the 2016 paper, including AGASEA over Thwaites Glacier (Holt et al., 2006), ATRS over West Antarctica (Peters et al., 2005), GIMBLE over Marie Byrd Land (Young et al, 2013) and parts of ICECAP over Wilkes Subglacial Basin, Dome C, Highland B and Totten Glacier. (Young et al, 2011, Young et al., 2016). We expect updates to the coverage as part of work funded by the Arête Glaciers Initiative.
References
Holt, J. W., Blankenship, D. D., Morse, D. L., Young, D. A., Peters, M. E., Kempf, S. D., Richter, T. G., Vaughan, D. G., and Corr, H., New boundary conditions for the West Antarctic ice sheet: subglacial topography of the Thwaites and Smith Glacier catchments, 2006, Geophysical Research Letters, 33 (L09502), pp., https://doi.org/10.1029/2005GL025561
Mouginot, J., Rignot, E., and Scheuchl, B., Continent-wide, interferometric SAR phase, mapping of Antarctic ice velocity, 2019, Geophysical Research Letters, 46(16), pp.9710-9718, https://doi.org/10.1029/2019GL083826
Peters, M. E., Blankenship, D. D., and Morse, D. L., Analysis techniques for coherent airborne radar sounding: Application to West Antarctic ice streams, 2005 ,Journal of Geophysical Research, 110(B06303), pp.,https://doi.org/10.1029/2004JB003222
Pritchard, H. D., and others.,Bedmap3 updated ice bed, surface and thickness gridded datasets for Antarctica,2025,Scientific Data,12(1), pp.414,https://doi.org/10.1038/s41597-025-04672-y
Young, D. A., D. D. Blankenship, J. S. Greenbaum, E. Quartini, G. L. Muldoon, F. Habbal, L. E. Lindzey, C. A. Greene, E. M. Powell, G. C. Ng, T. G. Richter, G. Echeverry, and S. Kempf, 2024, Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE) Airborne VHF Radar Transects: 2012/2013 and 2014/2015, https://doi.org/10.18738/T8/BMXUHX, Texas Data Repository
Young, D. A., Wright, A. P., Roberts, J. L., Warner, R. C., Young, N. W., Greenbaum, J. S., Schroeder, D. M., Holt, J. W., Sugden, D. E., Blankenship, D. D., van Ommen, T. D., and Siegert, M. J.,A dynamic early East Antarctic Ice Sheet suggested by ice covered fjord landscapes, 2011, Nature, 474, pp.72-75, https://doi.org/10.1038/nature10114
Young, D. A., Schroeder, D. M., Blankenship, D. D., Kempf, S. D., and Quartini, E.,The distribution of basal water between Antarctic subglacial lakes from radar sounding,2016,Philosophical Transactions of the Royal Society A, 374 (20140297), pp.1-21, https://doi.org/10.1098/rsta.2014.0297
Change Log
Changes from V1: changes to gridding parameters to more closely match the figures from Young 2016; updated metadata gridding descriptio
Driving into the sunset: Supporting cognitive functioning in older drivers
Full text linkCopyright @ 2011 Mark S. Young and David Bunce - This article has been made available through the Brunel Open Access Publishing Fund.The rise in the aging driver population presents society with a significant challenge-how to maintain safety and mobility on the roads. On the one hand, older drivers pose a higher risk of an at-fault accident on a mile-for-mile basis; on the other hand, independent mobility is a significant marker of quality of life in aging. In this paper, we review the respective literatures on cognitive neuropsychology and ergonomics to suggest a previously unexplored synergy between these two fields. We argue that this conceptual overlap can form the basis for future solutions to what has been called "the older driver problem." Such solutions could be found in a range of emerging driver assistance technologies offered by vehicle manufacturers, which have the potential to compensate for the specific cognitive decrements associated with aging that are related to driving.Support was received from the Leverhulme Trust, UK
Finite-Element Analysis of 3-D Viscous Flow and Mixed-Convection Problems by the Projection Method
No full textCorrelators of supersymmetric Wilson loops at weak and strong coupling
Full text linkBassetto A, Griguolo L, Pucci F, Seminara D, Thambyahpillai S, Young D. Correlators of supersymmetric Wilson loops at weak and strong coupling. Journal of High Energy Physics. 2010;2010(3): 38.We continue our study of the correlators of a recently discovered family of BPS Wilson loops in N = 4 supersymmetric U(N) Yang-Mills theory. We perform explicit computations at weak coupling by means of analytical and numerical methods finding agreement with the exact formula derived from localization. In particular we check the localization prediction at order g(6) for different BPS "latitude" configurations, the N = 4 perturbative expansion reproducing the expected results within a relative error of 10(-4). On the strong coupling side we present a supergravity evaluation of the 1/8 BPS correlator in the limit of large separation, taking into account the exchange of all relevant modes between the string worldsheets. While reproducing the correct geometrical dependence, we find that the associated coefficient does not match the localization result
A lifeline for Europe's young radical innovators
Full text linkIn this Policy Brief, Reinhilde Veugelers shows that Young Innovative Companies (YICs) in Europe achieve significantly higher innovative sales than other innovation-active firms, representing 36% of sales having market novelties. She also confirms that YICs are more affected by credit constraints than other innovation-active firms. If Europe is to exit the current crisis intact and fulfill its full growth potential in the medium term, the author therefore believes Europe must develop policies and incentives which are tailored to the needs of European young radical innovators.
Young equations with singularities
No full textIn this paper we prove existence and uniqueness of a mild solution to the Young equation dy(t)=Ay(t)dt+σ(y(t))dx(t), t∈[0,T], y(0)=ψ. Here, A is an unbounded operator which generates a semigroup of bounded linear operators (S(t))t≥0 on a Banach space X, x is a real-valued η-Hölder continuous. Our aim is to reduce, in comparison to Gubinelli et al. (2006) and Addona et al. (2022) (see also Deya et al. (2012) and Gubinelli and Tindel, (2010)), the regularity requirement on the initial datum ψ eventually dropping it. The main tool is the definition of a sewing map for a new class of increments which allows the construction of a Young convolution integral in a general interval [a,b]⊂R when the Xα-norm of the function under the integral sign blows up approaching a and Xα is an intermediate space between X and D(A)
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