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Sample records for lx-17 hockey puck

  1. Ignition and Growth Modeling of LX-17 Hockey Puck Experiments

    SciTech Connect

    Tarver, C M

    2004-04-19

    Detonating solid plastic bonded explosives (PBX) formulated with the insensitive molecule triaminotrinitrobenzene (TATB) exhibit measurable reaction zone lengths, curved shock fronts, and regions of failing chemical reaction at abrupt changes in the charge geometry. A recent set of ''hockey puck'' experiments measured the breakout times of diverging detonation waves in ambient temperature LX-17 (92.5 % TATB plus 7.5% Kel-F binder) and the breakout times at the lower surfaces of 15 mm thick LX-17 discs placed below the detonator-booster plane. The LX-17 detonation waves in these discs grow outward from the initial wave leaving regions of unreacted or partially reacted TATB in the corners of these charges. This new experimental data is accurately simulated for the first time using the Ignition and Growth reactive flow model for LX-17, which is normalized to a great deal of detonation reaction zone, failure diameter and diverging detonation data. A pressure cubed dependence for the main growth of reaction rate yields excellent agreement with experiment, while a pressure squared rate diverges too quickly and a pressure quadrupled rate diverges too slowly in the LX-17 below the booster equatorial plane.

  2. A comparison of the capacity of ice hockey goaltender masks for the protection from puck impacts.

    PubMed

    Nur, Sarah; Kendall, Marshall; Clark, J Michio; Hoshizaki, T Blaine

    2015-01-01

    Goaltenders in ice hockey are the only players that are on the ice for the entire game. Their position exposes them to impacts from collisions with other players, falls to the ice, and puck impacts. In competitive ice hockey leagues, head injuries resulting from puck impacts have been reported with some cases resulting in ending the player's career. Considerable research has been conducted to assess the performance of hockey helmets; however, few have assessed the performance of goaltenders' masks. The purpose of this study was to compare the capacity of four goaltenders' masks for the protection from puck impact as measured by head acceleration and peak force. A Hybrid III headform was fitted with four different goaltender masks and impacted with a hockey puck in three locations at 25 m/s. The masks were found to vary in the level of protection they offered as the mask with the thickest liner resulted in lower forces than the thinnest mask for side impacts; however, the thinnest mask resulted in the lowest force for front impacts. Despite performance differences at specific locations, no one mask proved to be superior as peak acceleration and peak force values did not exceed the thresholds necessary for concussion.

  3. Modeling LX-17 Detonation Growth and Decay Using the Ignition and Growth Model

    NASA Astrophysics Data System (ADS)

    Tarver, Craig M.; Chidester, Steven K.

    2009-12-01

    The previously established Ignition and Growth reactive flow model for the detonating triaminotrinitrobenzene (TATB) based plastic bonded explosive LX-17 is applied to recent experimental detonation propagation/failure experiments using unconfined, Lucite confined, and copper confined cylinders. The model also simulates two corner turning experiments in which steel and Lucite act as boundary materials. Finally, the model is used to calculate a one-inch diameter "Hockey Puck" test in which the booster explosive is HMX-based rather than TATB-based. Since the LX-17 Ignition and Growth model parameters are normalized to a great deal of one-, two- and three-dimensional detonation propagation data, they accurately predict all of this new experimental detonation velocity and arrival time data.

  4. Performance Prediction for a Hockey-Puck Silicon Crystal Monochromator at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Liu, Zunping; Rosenbaum, Gerd; Navrotski, Gary

    2014-03-01

    One of the Key Performance Parameters of the upgrade of the Advanced Photon Source (APS) is the increase of the storage ring current from 100 to 150 mA. In order to anticipate the impact of this increased heat load on the X-ray optics of the beamlines, the APS has implemented a systematic review, by means of finite element analysis and computational fluid dynamics, of the thermal performance of the different types of monochromators installed at the highest-heat-load insertion device beamlines. We present here simulations of the performance of a directly liquid nitrogen-cooled silicon crystal, the hockey-puck design. Calculations of the temperature and slope error at multiple ring currents under multiple operational conditions, including the influence of power, cooling, and diffraction surface thickness are included.

  5. CHARACTERIZATION OF THERMALLY DAMAGED LX-17

    SciTech Connect

    Hsu, P C

    2007-07-11

    Thermal damage was applied to LX-17 at 190 C for several hours. The damaged LX-17 samples, after cooled down to room temperature, were characterized for their material properties (density, porosity, permeability, moduli), safety, and performance. Weight losses upon thermal exposure were insignificant (< 0.1% wt.). The damaged LX-17 samples expanded, resulting in a bulk density reduction of 4.3%. Subsequent detonation measurements (cylinder tests) were conducted on the thermally-damaged LX-17 samples. The results showed that the fractions of damaged LX-17 reacted were slightly lower than those of pristine LX-17. The thermally damaged LX-17 had a detonation velocity of 7.315 mm/{micro}s, lower than that (7.638 mm/{micro}s) of pristine LX-17. Detonation energy density for the damaged LX-17 was 5.08 kJ/cm{sup 3}, about 9.0% lower than the detonation energy density of 5.50 kJ/cm{sup 3} for the pristine LX-17. The break-out curves showed reaction zone lengths for pristine LX-17 and damaged LX-17 were similar but the damaged samples had ragged detonation fronts.

  6. Multiple shock initiation of LX-17

    SciTech Connect

    Tarver, C.M.; Cook, T.M.; Urtiew, P.A.; Tao, W.C.

    1993-07-01

    The response of the insensitive TATB-based high explosive LX-17 to multiple shock impacts is studied experimentally in a four inch gas gun using embedded manganin gauges and numerically using the ignition and growth reactive flow model of shock initiation and detonation. Pressure histories are reported for LX-17 cylinders which are subjected to sustained shock pulses followed by secondary compressions from shocks reflected from metal discs attached to the backs of the explosive targets. These measured and calculated pressure histories show that the threshold for hot spot growth in LX-17 is 7 GPa, that LX-17 can be dead pressed at slightly lower pressures, and that the reaction rates behind reflected shocks increase greatly as the impedance of the metal increases. A study of the response of LX-17 to the collision of two reacting, diverging shocks forming a Mach stem wave inside the LX-17 charge demonstrated that this interaction can result in a high pressure region of sufficient size and strength to cause detonation under certain conditions.

  7. Puck collisions

    NASA Astrophysics Data System (ADS)

    Hauge, E. H.

    2012-09-01

    Collisions between two ice hockey pucks sliding on frictionless ice are studied, with both inelasticity and frictional contact between the colliding surfaces of the two pucks taken into account. The latter couples translational and rotational motion. The full solution depends on the sign and magnitude of the initial mismatch between the surface velocities at the point of contact. The initial state defines two physically distinct regimes for the friction coefficient. To illustrate the complexities, we discuss at length the typical situation (well known from curling) when puck number 1 is initially at rest, and is hit by puck number 2 with an arbitrary impact parameter, velocity and angular velocity. We find that the total outgoing angle between the pucks exceeds \\frac{1}{2}\\pi if and only if the collision leads to a net increase in the translational part of the kinetic energy. The conditions for this to happen are scrutinized, and the results are presented both analytically and numerically by a set of representative curves. This paper is written with an ambitious undergraduate, and her teacher, in mind.

  8. Air Gap Effects in LX-17

    SciTech Connect

    Souers, P C; Ault, S; Avara, R; Bahl, K L; Boat, R; Cunningham, B; Gidding, D; Janzen, J; Kuklo, D; Lee, R; Lauderbach, L; Weingart, W C; Wu, B; Winer, K

    2005-09-26

    Three experiments done over twenty years on gaps in LX-17 are reported. For the detonation front moving parallel to the gaps, jets of gas products were seen coming from the gaps at velocities greater than the detonation velocity. A case can be made that the jet velocity increased with gap thickness but the data is scattered. For the detonation front moving transverse to the gap, time delays were seen. The delays roughly increase with gap width, going from 0-70 ns at 'zero gap' to around 300 ns at 0.5-1 mm gap. Larger gaps of up to 6 mm width almost certainly stopped the detonation, but this was not proved. Real-time resolution of the parallel jets and determination of the actual re-detonation or failure in the transverse case needs to be done in future experiments.

  9. LX-17-1 Stockpile Returned Material Lot Comparison

    SciTech Connect

    Gagliardi, F.; Pease, S.; Willey, T.

    2015-02-18

    Many different lots of LX-17 have been produced over the years. Two varieties of LX-17, LX-17-0 and LX-17-1, have at one point or another been a part of the Livermore stockpile systems. LX-17-0 was made with dry-aminated TATB whereas LX-17-1 was made with wet-aminated TATB. Both versions have the same TATB to Kel-F 800 mass ratio of 92.5%/7.5%. Both kinds of LX-17 were formulated at Holston during the late 1970s or early to mid-1980s and were certified to have met the necessary specifications that cover the purity, particle size range, explosive to binder ratio, etc. In recent years, Trevor Willy and others have performed a detailed evaluation of solid parts made from each of the LX-17 lots manufactured at Holston. Using the Advanced Light Source at LBNL, Willey and his colleagues radiographed many samples from isostatic pressings using the same scanning conditions. In their investigation they identified that even though the bulk composition can be the same, there may exist a large spread in how smoothly the TATB and binder were distributed within the radiographed volume of different lots of material.1 Overall, the dry-aminated TATB-based material, LX-17-0, had a smooth TATB and binder distribution, whereas the wet-aminated TATB-based LX-17-1 showed a wide range of binder distributions. The results for five different LX-17-1 lots are shown in Figure 1. The wide variation in material distribution has raised the question about whether or not this sort variability will cause significant differences in mechanical behavior.

  10. LX-17 Deflagration at High Pressures and Temperatures

    SciTech Connect

    Koerner, J; Maienschein, J; Black, K; DeHaven, M; Wardell, J

    2006-10-23

    We measure the laminar deflagration rate of LX-17 (92.5 wt% TATB, 7.5 wt% Kel-F 800) at high pressure and temperature in a strand burner, thereby obtaining reaction rate data for prediction of thermal explosion violence. Simultaneous measurements of flame front time-of-arrival and temporal pressure history allow for the direct calculation of deflagration rate as a function of pressure. Additionally, deflagrating surface areas are calculated in order to provide quantitative insight into the dynamic surface structure during deflagration and its relationship to explosion violence. Deflagration rate data show that LX-17 burns in a smooth fashion at ambient temperature and is represented by the burn rate equation B = 0.2P{sup 0.9}. At 225 C, deflagration is more rapid and erratic. Dynamic deflagrating surface area calculations show that ambient temperature LX-17 deflagrating surface areas remain near unity over the pressure range studied.

  11. LX-17 and ufTATB Data for Corner-Turning, Failure and Detonation

    SciTech Connect

    Souers, P C; Lauderbach, L; Garza, R; Vitello, P; Hare, D E

    2010-02-03

    Data is presented for the size (diameter) effect for ambient and cold confined LX-17, unconfined ambient LX-17, and confined ambient ultrafine TATB. Ambient, cold and hot double cylinder corner-turning data for LX-17, PBX 9502 and ufTATB is presented. Transverse air gap crossing in ambient LX-17 is studied with time delays given for detonations that cross.

  12. Detonation Shock Dynamics (DSD) Calibration for LX-17

    SciTech Connect

    Aslam, Tariq D

    2012-04-24

    The goal of this report is to summarize the results of a Detonation shock dynamics (DSD) calibration for the explosive LX-17. Considering that LX-17 is very similar to PBX 9502 (LX-17 is 92.5% TATB with 7.5% Kel-F 800 binder, while PBX 9502 is 95% TATB with 5% Kel-F 800 binder), we proceed with the analysis assuming many of the DSD constants are the same. We only change the parameters D{sub CJ}, B and {bar C}{sub 6} ({bar C}{sub 6} controls the how D{sub CJ} changes with pressing density). The parameters D{sub CJ} and {bar C}{sub 6} were given by Josh Coe and Sam Shaw's EOS. So, only B was optimized in fitting all the calibration data. This report first discusses some general DSD background, followed by a presentation of the available dataset to perform the calibration, and finally gives the results of the calibration and draws some conclusions. A DSD calibration of LX-17 has been conducted using the existing diameter effect data and shock shape records. The new DSD fit is based off the current PBX 9502 calibration and takes into account the effect of pressing density. Utilizing the PBX 9502 calibration, the effects of initial temperature can also be taken into account.

  13. Dead Zones in LX-17 and PBX 9502

    SciTech Connect

    Souers, P C; Andreski, H G; Batteux, J; Bratton, B; Cabacungan, C; Cook, III, C F; Fletcher, S; Garza, R; Grimsley, D; Handly, J; Hernandez, A; McMaster, P; Molitoris, J D; Palmer, R; Prindiville, J; Rodriguez, J; Schneberk, D; Wong, B; Vitello, P

    2005-09-06

    Pin and X-ray corner-turning data have been taken on ambient LX-17 and PBX 9052, and the results are listed in tables as an aid to future modeling. The results have been modeled at 4 zones/mm with a reactive flow approach that varies the burn rate as a function of pressure. A single rate format is used to simulate failure and detonation in different pressure regimes. A pressure cut-off must also be reached to initiate the burn. Corner-turning and failure are modeled using an intermediate pressure rate region, and detonation occurs at high pressure. The TATB booster is also modeled using reactive flow, and X-ray tomography is used to partition the ram-pressed hemisphere into five different density regions. The model reasonably fits the bare corner-turning experiment but predicts a smaller dead zone with steel confinement, in contradiction with experiment. The same model also calculates the confined and unconfined cylinder detonation velocities and predicts the failure of the unconfined cylinder at 3.75 mm radius. The PBX 9502 shows a smaller dead zone than LX-17. An old experiment that showed a large apparent dead zone in Comp B was repeated with X-ray transmission and no dead zone was seen. This confirms the idea that a variable burn rate is the key to modeling. The model also produces initiation delays, which are shorter than those found in time-to-detonation.

  14. LX-17 Corner-Turning and Reactive Flow Failure

    SciTech Connect

    Souers, P C; Andreski, H; Cook III, C F; Garza, R; Pastrone, R; Phillips, D; Roeske, F; Vitello, P; Molitoris, J

    2004-03-11

    We have performed a series of highly-instrumented experiments examining corner-turning of detonation. A TATB booster is inset 15 mm into LX-17 (92.5% TATB, 7.5% kel-F) so that the detonation must turn a right angle around an air well. An optical pin located at the edge of the TATB gives the start time of the corner-turn. The breakout time on the side and back edges is measured with streak cameras. Three high-resolution X-ray images were taken on each experiment to examine the details of the detonation. We have concluded that the detonation cannot turn the corner and subsequently fails, but the shock wave continues to propagate in the unreacted explosive, leaving behind a dead zone. The detonation front farther out from the corner slowly turns and eventually reaches the air well edge 180{sup o} from its original direction. The dead zone is stable and persists 7.7 {micro}s after the corner-turn, although it has drifted into the original air well area. Our regular reactive flow computer models sometimes show temporary failure but they recover quickly and are unable to model the dead zones. We present a failure model that cuts off the reaction rate below certain detonation velocities and reproduces the qualitative features of the corner-turning failure.

  15. On sliding of a puck

    NASA Astrophysics Data System (ADS)

    Samsonov, V. A.

    2013-09-01

    Aleksandr Yul'evich Ishlinsky liked to consider a problem with some "special thrill" at the end of the Seminar meeting of the Chair of Applied Mathematics at the Faculty of Mechanics and Mathematics at M. V. Lomonosov Moscow State University. For example, in 1978 he asked the author of this paper to describe the process of sliding of a rotating hockey puck on ice. Somewhat later, on such a seminar, the author made his report and demonstrated the experimental results, which was approved by Aleksandr Yul'evich. But the small paper on this topic, delivered to the journal "Vestnik Moskovskogo Universiteta," was published only in 1981 [1] thanks to the support of Valentin Vitalievich Rumyantsev. The author thanks the Editorial Board of this journal for the possibility of discussing one of "Ishlinsky's problems" once again.

  16. Air Gaps, Size Effect, and Corner-Turning in Ambient LX-17

    SciTech Connect

    Souers, P C; Hernandez, A; Cabacungan, C; Fried, L; Garza, R; Glaesemann, K; Lauderbach, L; Liao, S; Vitello, P

    2008-02-05

    Various ambient measurements are presented for LX-17. The size (diameter) effect has been measured with copper and Lucite confinement, where the failure radii are 4.0 and 6.5 mm, respectively. The air well corner-turn has been measured with an LX-07 booster, and the dead-zone results are comparable to the previous TATB-boosted work. Four double cylinders have been fired, and dead zones appear in all cases. The steel-backed samples are faster than the Lucite-backed samples by 0.6 {micro}s. Bare LX-07 and LX-17 of 12.7 mm-radius were fired with air gaps. Long acceptor regions were used to truly determine if detonation occurred or not. The LX-07 crossed at 10 mm with a slight time delay. Steady state LX-17 crossed at 3.5 mm gap but failed to cross at 4.0 mm. LX-17 with a 12.7 mm run after the booster crossed a 1.5 mm gap but failed to cross 2.5 mm. Timing delays were measured where the detonation crossed the gaps. The Tarantula model is introduced as embedded in 0 reactive flow JWL++ and Linked Cheetah V4, mostly at 4 zones/mm. Tarantula has four pressure regions: off, initiation, failure and detonation. The physical basis of the input parameters is considered.

  17. Air Gaps, Size Effect, and Corner-Turning in Ambient LX-17

    SciTech Connect

    Souers, P C; Hernandez, A; Cabacungen, C; Fried, L; Garza, R; Glaesemann, K; Lauderbach, L; Liao, S; Vitello, P

    2007-05-30

    Various ambient measurements are presented for LX-17. The size (diameter) effect has been measured with copper and Lucite confinement, where the failure radii are 4.0 and 6.5 mm, respectively. The air well corner-turn has been measured with an LX-07 booster, and the dead-zone results are comparable to the previous TATB-boosted work. Four double cylinders have been fired, and dead zones appear in all cases. The steel-backed samples are faster than the Lucite-backed samples by 0.6 {micro}s. Bare LX-07 and LX-17 of 12.7 mm-radius were fired with air gaps. Long acceptor regions were used to truly determine if detonation occurred or not. The LX-07 crossed at 10 mm with a slight time delay. Steady state LX-17 crossed at 3.5 mm gap but failed to cross at 4.0 mm. LX-17 with a 12.7 mm run after the booster crossed a 1.5 mm gap but failed to cross 2.5 mm. Timing delays were measured where the detonation crossed the gaps. The Tarantula model is introduced as embedded in the Linked Cheetah V4.0 reactive flow code at 4 zones/mm. Tarantula has four pressure regions: off, initiation, failure and detonation. A report card of 25 tests run with the same settings on LX-17 is shown, possibly the most extensive simultaneous calibration yet tried with an explosive. The physical basis of some of the input parameters is considered.

  18. First-Generation Jet Propulsion Laboratory "Hockey-Puck" Free-Flying Magnetometers for Distributed In-Situ Multiprobe Measurement of Current Density Filamentation in the Northern Auroral Zone: Enstrophy Mission

    NASA Technical Reports Server (NTRS)

    Javadi, H.; Blaes, B.; Boehm, M.; Boykins, K.; Gibbs, J.; Goodman, W.; Lieneweg, U.; Lux, J.; Lynch, K.; Narvaez, P.

    2000-01-01

    magnetic signature electronic design and choice of materials in packaging. The miniaturized fluxgate magnetometers had a range of 1-60000 nT with 0.1% full-scale linearity. The frequency range of interest for magnetic measurement was 10 mHz - 50 Hz. Digital data from the magnetometer's three axes were placed in a 4MB Static Random Access Memory (SRAM) in data packages (frames) formatted together with time tags and frame ID. After a specified time was elapsed, the data were Viterbi encoded and transmitted at a rate of 100 kbps (BPSK). Each of the four FFMs transmitted at different frequency. These carrier frequencies were in the range of 2200-2300 MHz. The antenna was a single patch on a high dielectric constant substrate covering one end-plate of the hockey-puck-sized unit. The local clocks aboard the FFMs were reset at the start of the mission and stayed synchronized within 3 msec during the mission. Position of each FFM with respect to the rocket is calculated by the knowledge of its release velocity (measured at exit point of the FFM launcher tract) providing an accuracy of 1 m over the maximum range of 3 km. Spatial and temporal nature of observants can be separated to within 3 m in space or 3 msec time interval.

  19. A Comparison of New TATBs, FK-800 binder and LX-17-like PBXs to Legacy Materials

    SciTech Connect

    Willey, T M; DePiero, S C; Hoffman, D M

    2009-05-01

    Two newly synthesized versions of the insensitive high explosive (IHE) 1,3,5-triamino-2,4,6-trinitrobenzenes (TATBs) were compared to two legacy explosives currently used by the Department of Energy. Except for thermal analysis, small scale safety tests could not distinguish between the different synthetic routes. Morphologies of new TATBs were less faceted and more spherical. The particle size distribution of one new material was similar to legacy TATBs, but the other was very fine. Densities and submicron structure of the new TATBs were also significantly different from the legacy explosives. Pressed pellets of the new explosives were less dense. New FK-800 binder was used to prepare LX-17-like plastic bonded explosives (PBXs) from new and wet aminated TATB. Some mechanical, thermal and performance characterization of the new binder and LX-17-like PBXs was done. Significant differences were found. The reason for a number of these differences is not well understood.

  20. Characterization and Qualification of New TATB and Kel-F 800 for LX-17

    SciTech Connect

    Hoffman, D M; DePiero, S C

    2007-02-16

    The project would (1) compare new FK-800 with old Kel-F 800 and KF-800 lots currently available at LLNL, (2) compare and characterize new TATB with old TATB, (3) formulate new FK-800 with wet-aminated TATB and new TATBs in according to HAAP slurry coating procedure into LX-17-2, and (4) evaluate the mechanical and detonation performance characteristics of this insensitive high explosive (IHE). Priorities will be to prove that these new materials can be formulated, pressed to density and machined; and that they contain no impurities which might cause compatibility issues. Since 3M [1, 2], LANL [7], Pantex [8] and AWE [9, 10] are currently evaluating the new FK-800, we plan to share data rather than repeating their work. Our effort is briefly described: Task 1--Evaluation of newer characterization methods to identify structural variations between old and new Kel-F 800 including: Rheological and mechanical properties, copolymer content, degree of crystallinity, and interfacial interactions with TATB. Task 2--Evaluate TATBs using scattering techniques to replace sieving operations called out in the specification [12] for particle size distribution measurements. Use SEM and OM for morphological differences between the old and new explosives. Evaluate the compaction characteristics of new TATB. Task 3--Formulation of new LX-17-2 (with new FK-800 and/or new TATB) Task 4--Evaluate mechanical and performance properties of LX-17-2. At a minimum, compressive strength, dynamic mechanical behavior and a 2-inch cylinder shot should be performed and compared with existing data for LX-17-1.

  1. Development of a Detonation Profile Test for Studying Aging Effects in LX-17

    SciTech Connect

    Tran, T; Lewis, P; Tarver, C; Maienschein, J; Druce, R; Lee, R; Roeske, F

    2002-03-25

    A new small-scale Detonation Profile Test (DPT) is being developed to investigate aging effects on the detonation behavior of insensitive high explosives. The experiment involves initiating a small LX-17 cylindrical charge (12.7-19.1 mm diameter x 25.4-33 mm long) and measuring the velocity and curvature of the emerging detonation wave using a streak camera. Results for 12.7 mm diameter unconfined LX-17 charges show detonation velocity in the range between 6.79 and 7.06 km/s for parts up to 33 mm long. Since LX-17 can not sustain detonation at less than 7.3 km/s, these waves were definitely failing. Experiments with confined 12.7 mm diameter and unconfined 19.1 mm diameter samples showed wave velocities in the range of 7.4-7.6 km/s, values approaching steady state conditions at infinite diameter. Experiments with unconfined 19.1 mm diameter specimens are expected to provide reproducible and useful range of detonation parameters suitable for studying aging effects.

  2. Kick Dis Power Puck

    NASA Astrophysics Data System (ADS)

    Carlson, John E.

    2004-03-01

    There is a new toy available that can be used to demonstrate many interesting physics principles. It is called the "Kick Dis Power Puck" and is basically a round plastic hovercraft with a soft cushion material around the perimeter (Fig. 1). It is a product of the Estes Company, which is well known for their model rockets, and is available from advertisers in this journal.1,2 The puck has a diameter of 19.5 cm and comes in two colors, red or green. The two samples I purchased had masses of 307 g and 303 g, respectively. There is a forceful, built-in fan, which is run by a rechargeable battery and powers the puck for about 30 minutes. A 9-V battery charger completes the package, which sells for about 45.

  3. Explosive Model Tarantula 4d/JWL++ Calibration of LX-17

    SciTech Connect

    Souers, P C; Vitello, P A

    2008-09-30

    Tarantula is an explosive kinetic package intended to do detonation, shock initiation, failure, corner-turning with dead zones, gap tests and air gaps in reactive flow hydrocode models. The first, 2007-2008 version with monotonic Q is here run inside JWL++ with square zoning from 40 to 200 zones/cm on ambient LX-17. The model splits the rate behavior in every zone into sections set by the hydrocode pressure, P + Q. As the pressure rises, we pass through the no-reaction, initiation, ramp-up/failure and detonation sections sequentially. We find that the initiation and pure detonation rate constants are largely insensitive to zoning but that the ramp-up/failure rate constant is extremely sensitive. At no time does the model pass every test, but the pressure-based approach generally works. The best values for the ramp/failure region are listed here in Mb units.

  4. Double Shock Experiments and Reactive Flow Modeling on LX-17 to Understand the Reacted Equation of State

    NASA Astrophysics Data System (ADS)

    Vandersall, Kevin; Garcia, Frank; Fried, Laurence; Tarver, Craig

    2013-06-01

    Experimental data from measurements of the reacted state of an energetic material are desired to incorporate reacted states in modeling by computer codes. In a case such as LX-17 (92.5% TATB and 7.5% Kel-F by weight), where the time dependent kinetics of reaction is still not fully understood and the reacted state may evolve over time, this information becomes even more vital. Experiments were performed to measure the reacted state of LX-17 using a double shock method involving the use of two flyer materials (with known properties) mounted on the projectile that send an initial shock through the material close to or above the Chapman-Jouguet (CJ) state followed by a second shock at a higher magnitude into the detonated material. By measuring the parameters of the first and second shock waves, information on the reacted state can be obtained. The LX-17 detonation reaction zone profiles plus the arrival times and amplitudes of reflected shocks in LX-17 detonation reaction products were measured using Photonic Doppler Velocimetry (PDV) probes and an aluminum foil coated LiF window. A discussion of this work will include the experimental parameters, velocimetry profiles, data interpretation, reactive CHEETAH and Ignition and Growth modeling, as well as possible future experiments. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Double shock experiments and reactive flow modeling on LX-17 to understand the reacted equation of state

    NASA Astrophysics Data System (ADS)

    Vandersall, Kevin S.; Garcia, Frank; Fried, Laurence E.; Tarver, Craig M.

    2014-05-01

    Experimental data from measurements of the reacted state of an energetic material are desired to incorporate reacted states in modeling by computer codes. In a case such as LX-17 (92.5% TATB and 7.5% Kel-F by weight), where the time dependent kinetics of reaction is still not fully understood and the reacted state may evolve over time, this information becomes even more vital. Experiments were performed to measure the reacted state of LX-17 using a double shock method involving the use of two flyer materials (with known properties) mounted on the projectile that send an initial shock through the material close to or above the Chapman-Jouguet (CJ) state followed by a second shock at a higher magnitude into the detonated material. By measuring the parameters of the first and second shock waves, information on the reacted state can be obtained. The LX-17 detonation reaction zone profiles plus the arrival times and amplitudes of reflected shocks in LX-17 detonation reaction products were measured using Photonic Doppler Velocimetry (PDV) probes and an aluminum foil coated LiF window. A discussion of this work will include the experimental parameters, velocimetry profiles, data interpretation, reactive CHEETAH and Ignition and Growth modeling, as well as detail on possible future experiments.

  6. Eye injuries in Canadian amateur hockey.

    PubMed

    Pashby, T J

    1979-01-01

    Two studies, one retrospective (1972 to 1973) and one prospective (1974 to 1975), CONcerning eye injuries incurred by hockey players were conducted by the Canadian Ophthalmological Society with questionnaires to its members. Responses to the questionnaires were analyzed by age, type of injury, cause (i.e., hockey stick, puck, or other means), and results to visual acuity. The results were also designated by organized or unorganized participation. Almost 300 eye injuries were reported in each study. In the first study, 13.7% of the injured players became legally blind as a result of the injury; in the second study, 16% became legally blind. Organized hockey produced more injuries than unorganized hockey. The majority of the injuries were caused by the hockey stick. The injuries were both intraocular and extraocular. The group of 11- to 15-year olds received the highest number of injuries, and the older age group had the higher incidence of blindness. Studies have led to setting more rigid standards, altering rules of the game, and selecting face protectors for hockey players. Older players who care for their equipment prefer the plastic shield face protectors, and the younger players (who complain of fogging and scratching of the plastic) prefer mesh protectors through which neither the stick nor the puck can penetrate. New high sticking (above the shoulder level) rules were included in the 1976 official rule book for Canadian amateur hockey.

  7. The "Puck" energetic charged particle detector: Design, heritage, and advancements.

    PubMed

    Clark, G; Cohen, I; Westlake, J H; Andrews, G B; Brandt, P; Gold, R E; Gkioulidou, M A; Hacala, R; Haggerty, D; Hill, M E; Ho, G C; Jaskulek, S E; Kollmann, P; Mauk, B H; McNutt, R L; Mitchell, D G; Nelson, K S; Paranicas, C; Paschalidis, N; Schlemm, C E

    2016-08-01

    Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.

  8. The "Puck" energetic charged particle detector: Design, heritage, and advancements

    NASA Astrophysics Data System (ADS)

    Clark, G.; Cohen, I.; Westlake, J. H.; Andrews, G. B.; Brandt, P.; Gold, R. E.; Gkioulidou, M. A.; Hacala, R.; Haggerty, D.; Hill, M. E.; Ho, G. C.; Jaskulek, S. E.; Kollmann, P.; Mauk, B. H.; McNutt, R. L.; Mitchell, D. G.; Nelson, K. S.; Paranicas, C.; Paschalidis, N.; Schlemm, C. E.

    2016-08-01

    Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.

  9. Hockey night in phase space

    NASA Astrophysics Data System (ADS)

    Nichol, Kiri; Daniels, Karen

    2011-03-01

    In order to explore the possibility of developing a statistical mechanics for dissipative ensembles, we have performed an experiment in which we track the translational and rotational velocities of pucks on an air hockey table. The pucks are driven by bumpers at the boundaries and are bidisperse to prevent crystallization. At packing fractions of 60% we find that the system distributes rotational and translation energy according to the equipartition theorem. However, as the packing fraction increases, the ratio of rotational energy to translational energy also increases to a value larger than predicted by equipartition. The translational and angular velocity distributions are approximately exponential and the distributions of the translational velocity are the same for both large and small particles. In contrast, the distribution of the angular velocities is broader for the small particles than for the large.

  10. End-Effector Development for the PIP Puck Handling Robot

    SciTech Connect

    Fowley, M.D.

    2001-01-31

    It has been decided that excess, weapons-grade plutonium shall be immobilized to prevent nuclear proliferation. The method of immobilization is to encapsulate the plutonium in a ceramic puck, roughly the size of a hockey puck, using a sintering process. This method has been officially identified as the Plutonium Immobilization Process (PIP). A Can-in-Canister storage method will be used to further immobilize the plutonium. The Can-in-Canister method uses the existing design of a Defense Waste Processing Facility (DWPF) canister to house the plutonium pucks. the process begins with several pucks being stacked in a stainless steel can. Several of the stainless steel cans are stacked in a cage-like magazine. Several of the magazines are then placed in a DWPF canister. The DWPF canister is then filled with molten glass containing high-level, radioactive waste from the DWPF vitrification process. The Can-in-Canister method makes reclamation of plutonium from the pucks technically difficult and highly undesirable. The mechanical requirements of the Can-in-Canister process, in conjunction with the amount of time required to immobilize the vast quantities of weapons-grade plutonium, will expose personnel to unnecessarily high levels of radiation if the processes were completed manually, in glove boxes. Therefore, automated equipment is designed into the process to reduce or eliminate personnel exposure. Robots are used whenever the automated handling operations become complicated. There are two such operations in the initial stages of the Can-in-Canister process, which required a six-axis robot. The first operation is a press unloading process. The second operation is a tray transfer process. To successfully accomplish the operational tasks described in the two operations, the end-effector of the robot must be versatile, lightweight, and rugged. As a result of these demands, an extensive development process was undertaken to design the optimum end-effector for these puck

  11. End-Effector Development for the PIP Puck Handling Robot

    SciTech Connect

    Fowley, M.D.

    2001-01-03

    It has been decided that excess, weapons-grade plutonium shall be immobilized to prevent nuclear proliferation. The method of immobilization is to encapsulate the plutonium in a ceramic puck, roughly the size of a hockey puck, using a sintering process. This method has been officially identified as the Plutonium Immobilization Process (PIP). A Can-in-Canister storage method will be used to further immobilize the plutonium. The Can-in-Canister method uses the existing design of a Defense Waste Processing Facility (DWPF) canister to house the plutonium pucks. the process begins with several pucks being stacked in a stainless steel can. Several of the stainless steel cans are stacked in a cage-like magazine. Several of the magazines are then placed in a DWPF canister. The DWPF canister is then filled with molten glass containing high-level, radioactive waste from the DWPF vitrification process. The Can-in-Canister method makes reclamation of plutonium from the pucks technically difficult and highly undesirable. The mechanical requirements of the Can-in-Canister process, in conjunction with the amount of time required to immobilize the vast quantities of weapons-grade plutonium, will expose personnel to unnecessarily high levels of radiation if the processes were completed manually, in glove boxes. Therefore, automated equipment is designed into the process to reduce or eliminate personnel exposure. Robots are used whenever the automated handling operations become complicated. There are two such operations in the initial stages of the Can-in-Canister process, which required a six-axis robot. The first operation is a press unloading process. The second operation is a tray transfer process. To successfully accomplish the operational tasks described in the two operations, the end-effector of the robot must be versatile, lightweight, and rugged. As a result of these demands, an extensive development process was undertaken to design the optimum end-effector for these puck

  12. ONE-DIMENSIONAL TIME TO EXPLOSION (THERMAL SENSITIVITY) TESTS ON PETN, PBX-9407, LX-10, AND LX-17

    SciTech Connect

    Hsu, Peter C.; Strout, Steve; McClelland, Matthew; Ellsworth, Fred Ellsworth

    2016-01-28

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to thermal explosion, threshold thermal explosion temperature, and determine the kinetic parameters of thermal decomposition of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the results of our recent ODTX experiments on PETN powder, PBX-9407 pressed part, LX-10 pressed part, LX-17 pressed part and compares the test data that were obtained decades ago with the older version of ODTX system. Test results show the thermal sensitivity of various materials tested in the following order: PETN> PBX-9407 > LX-10 > LX-17.

  13. Le Hockey [Hockey]. Teacher's Guide.

    ERIC Educational Resources Information Center

    Balchunas, Martha; Ullmann, Rebecca

    A resource kit for the teaching of French at the intermediate level is represented by a teacher's guide and the duplicating master for a tape transcript. The aim of this module is to make the elementary or secondary school student of French familiar with basic hockey terms in French, and to enable the student to understand hockey games broadcast…

  14. Formulation and Characterization of LX-17-2 from new FK 800 binder and WA, ATK, and BAE TATBs

    SciTech Connect

    DePiero, S C; Hoffman, D M

    2007-08-03

    Currently LLNL has no Kel-F 800 or wet-aminated TATB reserves for formulation. Although both materials are soon to be commercially available, their synthesis processes have changed and the explosive must be re-evaluated. In 2000 3M phased out the uses of perfluorooctanoyl (C8) derivatives due to environmental persistence and bioaccumulation issues. A C8 derivative was used as an emulsifier for making Kel F-800. In 2001 Kel F-800 was scheduled to be discontinued and the last Kel F-800 run was made in early 2002. LANL ordered 2M$ worth of Kel-F 800 for reserves and Pantex purchased several hundred pounds to satisfy mock needs. After four years, 3M has decided to introduce a Kel-F 800-like polymer based on a new emulsifier using the same chlorotrifluoroethylene and vinylidene fluoride monomers and emulsion polymerization process. They have produced 3 batches and claim the 'new' FK-800 is indistinguishable from the 'old' Kel-F 800 in any of their testing parameters. In June-July 2006 3M scaled up a batch of about 800 pounds and have test quantities available. We have samples of the new FK-800 for evaluation. Neither wet nor dry-aminated TATB has been synthesized in the US in any significant quantity since about 1985 and significant quantities of LX-17-1 has not been formulated since about 1990. Over the last few years as part of a DOD MANTECH, ATK Thiokol and BAE Holston Army Ammunition Plant (HAAP) have produced moderate quantities of TATB ({approx}5 kg batches) with plans to scale up for DOD applications. Thiokol TATB is polycrystalline with an average particle size of about 40 m (similar to WA TATB) but HAAP TATB is only 5-6 {micro}m (similar to ultrafine). We have obtained small quantities of these materials for evaluation. The project (1) compares new FK-800 with old Kel-F 800 and FK-800 lots currently available at LLNL, (2) compares and characterizes new TATB with old TATB, (3) formulates new FK-800 with wet-aminated TATB and new TATBs in according to HAAP slurry

  15. APPLICATION OF THE EMBEDDED FIBER OPTIC PROBE IN HIGH EXPLOSIVE DETONATION STUDIES: PBX-9502 AND LX-17

    SciTech Connect

    Hare, D; Goosman, D; Lorenz, K; Lee, E

    2006-09-26

    The Embedded Fiber Optic probe directly measures detonation speed continuously in time, without the need to numerically differentiate data, and is a new tool for measuring time-dependent as well as steady detonation speed to high accuracy. It consists of a custom-design optical fiber probe embedded in high explosive. The explosive is detonated and a refractive index discontinuity is produced in the probe at the location of the detonation front by the compression of the detonation. Because this index-jump tracks the detonation front a measurement of the Doppler shift of laser light reflected from the jump makes it possible to continuously measure detonation velocity with high spatial and temporal resolution. We have employed this probe with a Fabry-Perot-type laser Doppler velocimetry system additionally equipped with a special filter for reducing the level of non-Doppler shifted light relative to the signal. This is necessary because the index-jump signal is relatively weak compared to the return expected from a well-prepared surface in the more traditional and familiar example of material interface velocimetry. Our observations were carried out on a number of explosives but this work is focused on our results on PBX-9502 (95% TATB, 5% Kel-F) and LX-17 (92.5% TATB, 7.5% Kel-F) at varying initial charge density. Our measurements reveal a density dependence significantly lower than previous quoted values and lower than theoretical calculations. Our limited data on detonation speed dependence on wave curvature is in reasonable agreement with previous work using more standard methods and confirms deviation from the Wood-Kirkwood theoretical formula.

  16. Hockey, iPads, and Projectile Motion in a Physics Classroom

    ERIC Educational Resources Information Center

    Hechter, Richard P.

    2013-01-01

    With the increased availability of modern technology and handheld probeware for classrooms, the iPad and the Video Physics application developed by Vernier are used to capture and analyze the motion of an ice hockey puck within secondary-level physics education. Students collect, analyze, and generate digital modes of representation of physics…

  17. Hockey, iPads, and Projectile Motion in a Physics Classroom

    NASA Astrophysics Data System (ADS)

    Hechter, Richard P.

    2013-09-01

    With the increased availability of modern technology and handheld probeware for classrooms, the iPad1 and the Video Physics2 application developed by Vernier are used to capture and analyze the motion of an ice hockey puck within secondary-level physics education. Students collect, analyze, and generate digital modes of representation of physics phenomena using modern technologies to complement theoretical plots. This activity acknowledges hockey players' implicit understanding of the launch angle and initial velocity of a saucer pass as basic projectile motion while engaging students in authentic physics-based problem solving.

  18. Thermopower Puck for Measurement of Thermodynamic Properties

    NASA Astrophysics Data System (ADS)

    Vargas, Andres; Fukuda, Ryan; Soliz, Nicholas; Ho, Pei-Chun

    2014-03-01

    A thermopower puck was created in order to measure the thermoelectric power and thermal conductance of strongly correlated electron materials from 10K to 300K. The puck consists of a 2k Ω resistivity heater and 2 thermometers. The heater is connected to the top of the sample and applies heat until thermal equilibrium is reached. This creates a temperature gradient across the sample and is read by the 2 thermometers, one reading the hotter temperature and the other reading the colder temperature. The wire that is used as the thermal anchor for the high temperature thermometer, which is electrically isolated from thermometer, is also used as one of the leads to measure the thermal voltage produced across the sample. To calibrate the measurement probe, the thermoelectric power and thermal conductance of a nickel sample, which was purchased from Quantum Design, was measured. The data obtained qualitatively agrees with the literature data provided to us by Quantum Design. For future work, we will be using the measurement probe to investigate the thermodynamic properties of intermetallic compounds. Research at CSU-Fresno is supported by NSF DMR-1104544. Felipe Vargas is also supported by Undergraduate Research Grant at CSU Fresno.

  19. Ice Hockey Injuries.

    ERIC Educational Resources Information Center

    Sim, Franklin H.; Simonet, William T.

    1988-01-01

    The article describes the mechanisms, management, and prevention of each type of injury to which hockey players are prone. It surveys the injuries sustained by ice hockey players and discusses treatment of specific injuries, including those injuries to the head, eye, shoulder, hand, thigh, scalp, and face. (JL)

  20. Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique

    SciTech Connect

    Hare, D E; Chandler, J B; Compton, S M; Garza, R G; Grimsley, D A; Hernandez, A; Villafana, R J; Wade, J T; Weber, S R; Wong, B M; Souers, P C

    2008-01-16

    The detailed history of the shock/detonation wave propagation after crossing a room-temperature-room-pressure (RTP) air gap between a 25.4 mm diameter LX-17 donor column and a 25.4 mm diameter by 25.4 mm long LX-17 acceptor pellet is investigated for three different gap widths (3.07, 2.08, and 0.00 mm) using the Embedded Fiber Optic (EFO) technique. The 2.08 mm gap propagated and the 3.07 mm gap failed and this can be seen clearly and unambiguously in the EFO data even though the 25.4 mm-long acceptor pellet would be considered quite short for a determination by more traditional means such as pins.

  1. Physiology of ice hockey.

    PubMed

    Montgomery, D L

    1988-02-01

    Ice hockey is characterized by high intensity intermittent skating, rapid changes in velocity and duration, and frequent body contact. The typical player performs for 15 to 20 minutes of a 60-minute game. Each shift lasts from 30 to 80 seconds with 4 to 5 minutes of recovery between shifts. The intensity and duration of a particular shift determines the extent of the contribution from aerobic and anaerobic energy systems. The high intensity bursts require the hockey player to develop muscle strength, power, and anaerobic endurance. The length of the game and the need to recover quickly from each shift demands a good aerobic system. Physical characteristics of elite players show that defensemen are taller and heavier than forwards probably due to positional demands. Hockey players are mesomorphic in structure. They are relatively lean since excess mass is detrimental to their skating performance. There is a large interindividual variability in VO2 during skating. Both the aerobic and anaerobic energy systems are important during a hockey game. Peak heart rates during a shift on the ice exceed 90% of HRmax with average on-ice values of about 85% of HRmax. Blood lactate is elevated above resting values confirming the anaerobic nature of the game. Glycogen depletion studies show a preferential utilisation of glycogen from the slow twitch fibres but also significant depletion from the fast twitch fibres. Elite hockey players display a muscle fibre composition similar to untrained individuals. Physiological profiles of elite hockey teams reveal the importance of aerobic endurance, anaerobic power and endurance, muscular strength and skating speed. Training studies have attempted to improve specific components of hockey fitness. Using traditional laboratory tests, a season of hockey play shows gains in anaerobic endurance but no change in aerobic endurance. On-ice tests of hockey fitness have been recommended as an essential part of the hockey player's physiological

  2. Concussion in ice hockey.

    PubMed

    Bonfield, Christopher M; Wecht, Daniel A; Lunsford, L Dade

    2014-01-01

    Ice hockey is an aggressive and fast-paced sport which has a high risk of injury, concussions in particular. Although serious head injury has been recognized for nearly 50 years, an increase in mainstream media attention in recent years has led to unprecedented public awareness. As a result, the National Hockey League (NHL) and other professional leagues around the world have initiated concussion protocols in order to better prevent, recognize, and treat concussions. With over 1,000,000 youth hockey participants in Canada and the USA combined, concussion is an issue that reaches beyond the professional level. In this report we review the incidence, evaluation, treatment, return-to-play protocol, and prevention efforts related to concussion in ice hockey.

  3. Brain contusion with aphasia following an ice hockey injury.

    PubMed

    Degen, Ryan M; Fink, Matthew E; Callahan, Lisa; Fibel, Kenton H; Ramsay, Jim; Kelly, Bryan T

    2016-09-01

    Head injuries are relatively common in ice hockey, with the majority represented by concussions, a form of mild traumatic brain injury. More severe head injuries are rare since the implementation of mandatory helmet use in the 1960s. We present a case of a 27 year-old male who sustained a traumatic intraparenchymal hemorrhage with an associated subdural hematoma resulting after being struck by a puck shot at high velocity. The patient presented with expressive aphasia, with no other apparent neurologic deficits. Acutely, he was successfully treated with observation and serial neuroimaging studies ensuring an absence of hematoma expansion. After a stable clinical picture following 24 hours of observation, the patient was discharged and managed with outpatient speech therapy with full resolution of symptoms and return to play 3 months later. We will outline the patient presentation and pertinent points in the management of acute head injuries in athletes.

  4. Isolated scapula fracture: Ice hockey player without trauma

    PubMed Central

    Memişoğlu, Serdar; Yılmaz, Barış; Aktaş, Erdem; Kömür, Baran

    2015-01-01

    Introduction Scapular fractures are generally occur from in high-energy traumas and are associated with a high incidence of morbidity and mortality. Presentation of case We present an unusual scapular fracture that occurred with a rare mechanism. A 23-year-old male patient who led an active sports life for 10 years and played ice hockey for the last 5 years. In a competition, he felt a sudden pain in his right scapula after hit the puck. He did not experience any direct trauma to his shoulder and there was no evidence of any pathological fracture. The fracture was isolated in the scapular body and it was classified as type 4, according to Hardegger classification. The was patient immobilized with a Velpau bandage for three weeks and then treated with physiotherapy for shoulder rehabilitation. Discussion The fracture mechanism was likely a disharmonius contracture of the agonist and antagonist muscles of the shoulder joint while hitting the puck. Conclusion Scapular fractures are generally seen along with other injuries, but in this case we wanted to emphasize that care has to been taken to diagnose an isolated scapular fracture while assessing shoulder pain. PMID:26587232

  5. A Hockey Hero

    ERIC Educational Resources Information Center

    Bolduc, Matt

    2009-01-01

    In this article, the author shares the story of Will Poulos, a hockey player who has developmental and physical disabilities (mild mental retardation and left cerebral palsy). Will has overcome tremendous obstacles in his life. He was born at 28 weeks in 1986 at three pounds, one ounce, and 19 inches long. He was very sick; his odds for survival…

  6. Polonium 210Po in the phytobenthos from Puck Bay.

    PubMed

    Skwarzec, B; Ulatowski, J; Strumińska, D I; Falandysz, J

    2003-04-01

    The aim of the work was to determine the 210Po content in phytobenthos species (seaweeds and angiosperms) from Puck Bay (southern Baltic). Alpha spectrometry was used to measure and calculate the activities and concentrations of polonium 210Po in the phytobenthos. The activity of 210Po in Puck Bay waters was determined to estimate the bioconcentration factors (BCF) of these plants. The 210Po concentration in water was estimated at 0.25 mBq dm(-3). The lowest polonium concentration in the phytobenthos was found in Cladophora rupestris (0.12 Bq kg(-1) wet wt.), the highest in Chara crinita (1.12 Bq kg(-1) wet wt.). Polonium is accumulated in these phytobenthos species; the bioconcentration factors (BCF) ranged from 450 to 4400.

  7. The Hockey/Art Alliance

    ERIC Educational Resources Information Center

    Wadeson, Harriet; Wirtz, Gail

    2005-01-01

    Ice hockey can be a violent sport as evidenced by the fighting among the members of an ice hockey team of 13-year-old boys from mixed racial and socioeconomic backgrounds. Two series of eight art sessions were used to help the boys develop respect for themselves and others, to solve conflicts without combat, and to build more positive…

  8. [Prospective study on injuries of the German national ice hockey teams in more than 1000 games].

    PubMed

    Gröger, A; Kuropkat, C; Mang, A; Gradinger, R

    2010-06-01

    Due to the fast and physical nature of the game, prevention of injuries is an important issue in ice hockey. The injuries of the German male senior and junior (U16, U17, U18, U19, U20) national ice hockey teams were documented and analyzed in 1006 games between 1986 and 2006. This unique long observation period over 20 years, as well as the standardized protocol of documentation provides reliable data concerning injury pattern in German international ice hockey. Overall 277 injuries were recorded. Comparing the first and the last ten years of observation, the number did not decline over the time, despite various national and international efforts of injury prevention. The majority of the injuries, almost 60%, were caused by body contact with increasing tendency. Remarkably, the injuries with no body or puck/stick contact more than doubled in the last ten years compared to the first ten years of observation. Most injuries happened to the extremities with decreasing tendency to lower body and increasing tendency to upper body injuries. The number of head injuries did not change significantly. More injuries occurred in the second and third period compared to the first period of the game. The data of this study indicate that many injuries might be due to insufficient physical condition with consecutive lack of concentration and coordination. Players do not seem to meet the increasing technical and athletic requirements of international ice-hockey. The increasing speed and physical energy in international ice-hockey make the game unique and fascinating. Therefore, the aim must be to decrease the number and above all the severity of injuries by further development and adjustment of the player's equipment. Also, a better cooperation of players, coaches, sports medicine and referees seems to be necessary for injury prevention in the future.

  9. Quiet eye predicts goaltender success in deflected ice hockey shots.

    PubMed

    Panchuk, Derek; Vickers, Joan N; Hopkins, Will G

    2017-02-01

    In interceptive timing tasks, long quiet eye (QE) durations at the release point, along with early tracking on the object, allow performers to couple their actions to the kinematics of their opponent and regulate their movements based on emergent information from the object's trajectory. We used a mobile eye tracker to record the QE of eight university-level ice hockey goaltenders of an equivalent skill level as they responded to shots that deflected off a board placed to their left or right, resulting in a trajectory with low predictability. QE behaviour was assessed using logistic regression and magnitude-based inference. We found that when QE onset occurred later in the shot (950 ± 580 ms, mean ± SD) there was an increase in the proportion of goals allowed (41% vs. 22%) compared to when QE onset occurred earlier. A shorter QE duration (1260 ± 630 ms) predicted a large increase in the proportion of goals scored (38% vs. 14%). More saves occurred when QE duration (2074 ± 47 ms) was longer. An earlier QE offset (2004 ± 66 ms) also resulted in a large increase in the number of goals allowed (37% vs. 11%) compared to a later offset (2132 ± 41 ms). Since an early, sustained QE duration contributed to a higher percentage of saves, it is important that coaches develop practice activities that challenge the goaltender's ability to fixate the puck early, as well as sustain a long QE fixation on the puck until after it is released from the stick.

  10. International Toys in Space: Hockey

    NASA Video Gallery

    Cosmonauts Sergi Treschev and Valery Korzun discover ways to adapt the game of hockey while trying to overcome the challenges of playing the game in microgravity. Astronaut Peggy Whitson narrates t...

  11. Massachusetts Special Olympics Poly Hockey.

    ERIC Educational Resources Information Center

    Morrissey, Jim

    Poly Hockey is featured in this manual of instructions for coaches and teachers to use with mentally retarded boys and girls of all ages and ability levels. It is noted that the sport has been supported by the Board of Directors of the Special Olympics and has been used in Massachusetts for over 7 years. Explained is use of the game indoors, and…

  12. Evaluation of cricket helmet performance and comparison with baseball and ice hockey helmets

    PubMed Central

    McIntosh, A; Janda, D

    2003-01-01

    Background: Protective helmets in sport are important for reducing the risk of head and facial injury. In cricket and other sports with projectiles, national test standards control the minimum helmet performance. However, there are few field data showing if helmets are effective in reducing head injury. Objectives: (a) To examine the performance of cricket helmets in laboratory tests; (b) to examine performance with regard to test standards, game hazards, and helmet construction; (c) to compare and contrast these findings with baseball and ice hockey helmets. Methods: Impact tests were conducted on a selection of helmet models: five cricket, two baseball, and two ice hockey. Ball to helmet impacts at speeds of 19, 27, 36, and 45 m/s were produced using an air cannon and a Hybrid III dummy headform and neck unit. Free fall drop tests with a rigid headform on to a selection of anvils (flat rigid, flat deformable, and hemispherical rigid) were conducted. Resultant headform acceleration was measured and compared between tests. Results: At the lower speed impacts, all helmets produced a good reduction in headform acceleration, and thus injury risk. At the higher speed impacts, the effectiveness was less. For example, the mean maximum headform accelerations for all cricket helmets at each speed were: 67, 160, 316, and 438 g for 19, 27, 36, and 45 m/s ball speeds respectively. Drop tests on to a hemispherical anvil produced the highest accelerations. The variation in performance increased as the magnitude of the impact energy increased, in both types of testing. Conclusions: The test method used for baseball helmets in which the projectile is fired at the helmet may be superior to helmet drop tests. Cricket helmet performance is satisfactory for low speed impacts, but not for impacts at higher, more realistic, speeds. Baseball and ice hockey helmets offer slightly better relative and absolute performance at the 27 m/s ball and puck impacts. PMID:12893718

  13. Visual Attentional Orienting in Developing Hockey Players.

    ERIC Educational Resources Information Center

    Enns, James T.; Richards, James C.

    1997-01-01

    Covert visual orienting was measured in 13 twelve-year-old and 11 fifteen-year-old hockey players and in 13 college students with no hockey training. Found that high-skill 15-year-olds were better able than all other groups to take advantage of the general alerting effect produced by the sudden onset of a cue. (MDM)

  14. Maintaining hydration with a carbohydrate-electrolyte solution improves performance, thermoregulation, and fatigue during an ice hockey scrimmage.

    PubMed

    Linseman, Mark E; Palmer, Matthew S; Sprenger, Heather M; Spriet, Lawrence L

    2014-11-01

    Research in "stop-and-go" sports has demonstrated that carbohydrate ingestion improves performance and fatigue, and that dehydration of ∼1.5%-2% body mass (BM) loss results in decreased performance, increased fatigue, and increased core temperature. The purpose of this investigation was to assess the physiological, performance, and fatigue-related effects of maintaining hydration with a carbohydrate-electrolyte solution (CES) versus dehydrating by ∼2% BM (no fluid; NF) during a 70-min ice hockey scrimmage. Skilled male hockey players (n = 14; age, 21.3 ± 0.2 years; BM, 80.1 ± 2.5 kg; height, 182.0 ± 1.2 cm) volunteered for the study. Subjects lost 1.94% ± 0.1% BM in NF, and 0.12% ± 0.1% BM in CES. Core temperature (Tc) throughout the scrimmage (10-50 min) and peak Tc (CES: 38.69 ± 0.10 vs. NF: 38.92 ± 0.11 °C; p < 0.05) were significantly reduced in CES compared with NF. Players in CES had increased mean skating speed and time at high effort between 30-50 min of the scrimmage. They also committed fewer puck turnovers and completed a higher percentage of passes in the last 20 min of play compared with NF. Postscrimmage shuttle skating performance was improved in CES versus NF and fatigue was lower following the CES trial. The results indicated that ingesting a CES to maintain BM throughout a 70-min hockey scrimmage resulted in improved hockey performance and thermoregulation, and decreased fatigue as compared with drinking no fluid and dehydrating by ∼2%.

  15. Hockey Stats: Data Collection on Ice.

    ERIC Educational Resources Information Center

    Harris, Joanne

    2002-01-01

    Part of a series exploring how mathematics is used in the workplace. Software developers and statisticians record data of hockey games and players using statistics accessible to middle school students. (MM)

  16. Injury potential in modern ice hockey.

    PubMed

    Sim, F H; Chao, E Y

    1978-01-01

    The majority of the damaging forces to the soft tissue, bone, and articular joint structures of modern hockey players during the energetic activities involved in the game are attributable to impact action during high-speed motion. In addition, non-contact musculoligamentous injuries are common because of the complex forces that are involved. The injury potential of this sport is assessed indirectly from the force and motion involved. The experimental method of measuring the kinematic motion and the impact forces inherent to the sport are presented. Although hockey is a fast and furious game with high injury potential, fortunately the number of serious injuries is not as great as one might expect.

  17. Change Agent Research for Windsor Minor Hockey.

    ERIC Educational Resources Information Center

    Moriarty, Dick; Duthie, James

    This study was based on an earlier 1972-73 study (see SP 009 113) which led to organizational restructuring of Windsor minor hockey (WMH). It was felt that further studies comparing attitudes and beliefs with behavior would be beneficial. Of particular interest were: (a) whether or not attitudes and beliefs changed due to adjusted organization and…

  18. Cohesion predicts success in junior ice hockey.

    PubMed

    Salminen, S; Luhtanen, P

    1998-10-01

    This study examined the relationship between cohesion measured by the Group Environment Questionnaire and success measured by winning percentage with over 200 junior ice hockey players. The cohesion explained 29% of the variance of the success. Scores on task cohesion were better predictors of success than social cohesion.

  19. Benthic re-colonization in post-dredging pits in the Puck Bay (Southern Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Szymelfenig, Maria; Kotwicki, Lech; Graca, Bożena

    2006-07-01

    The stage of benthic re-colonization at a site formed by sand extraction was investigated some 10 years after the cessation of dredging. The examined post-dredging pit is one of five deep (up to 14 m) pits created with a static suction hopper on the sandy, flat and shallow (1-2 m) part of the inner Puck Bay (the southern Baltic Sea). The topography of the dredged area makes a specific trap for different kinds of organic matter. It is created by the small areas of post-dredging pits as compared to their depths. As a result, organic matter accumulation leads to anaerobic conditions and hydrogen sulfide formation. Macrofauna was not found to occur permanently in the deepest part (11 m) of the cup-shaped depression, which was characterized by its small area (0.2 km 2) and steep walls. However, permanent occurrence of meiofauna (max. 180 ind. 10 cm -2, mainly Nematoda) was noted. Undoubtedly, re-colonization of benthic fauna assemblages, typical of shallow and sandy seabed of the Puck Bay, will not follow in a natural way in the area of post-dredging pits. Also, it could not be expected that the re-colonization sequence would result in the formation of a structure similar to that of the natural depression (the Kuźnica Hollow).

  20. Social determinants of violence in hockey: a review.

    PubMed

    Smith, M D

    1979-03-01

    Research on the social determinants of hockey violence is organized in this paper under three main headings: (1) the social organization of the hockey "system", (2) mass media portrayals of the professional game, and (3) the influence of players' reference others. It appears that these determinants all contribute to a social environment in which hockey performers perceive that the rewards of violence often outweigh the costs.

  1. Hockey STAR: A Methodology for Assessing the Biomechanical Performance of Hockey Helmets.

    PubMed

    Rowson, Bethany; Rowson, Steven; Duma, Stefan M

    2015-10-01

    Optimizing the protective capabilities of helmets is one of several methods of reducing brain injury risk in sports. This paper presents the experimental and analytical development of a hockey helmet evaluation methodology. The Summation of Tests for the Analysis of Risk (STAR) formula combines head impact exposure with brain injury probability over the broad range of 227 head impacts that a hockey player is likely to experience during one season. These impact exposure data are mapped to laboratory testing parameters using a series of 12 impact conditions comprised of three energy levels and four head impact locations, which include centric and non-centric directions of force. Injury risk is determined using a multivariate injury risk function that incorporates both linear and rotational head acceleration measurements. All testing parameters are presented along with exemplar helmet test data. The Hockey STAR methodology provides a scientific framework for manufacturers to optimize hockey helmet design for injury risk reduction, as well as providing consumers with a meaningful metric to assess the relative performance of hockey helmets.

  2. Hockey-stick steam generator for LMFBR

    SciTech Connect

    Hallinan, G.J.; Svedlund, P.E.

    1981-01-01

    This paper presents the criteria and evaluation leading to the selection of the Hockey Stick Steam Generator Concept and subsequent development of that concept for LMFBR application. The selection process and development of the Modular Steam Generator (MSG) is discussed, including the extensive test programs that culminated in the manufacture and test of a 35 MW(t) Steam Generator. The design of the CRBRP Steam Generator is described, emphasizing the current status and a review of the critical structural areas. CRBRP steam generator development tests are evaluated, with a discussion of test objectives and rating of the usefulness of test results to the CRBRP prototype design. Manufacturing experience and status of the CRBRP prototype and plant units is covered. The scaleup of the Hockey Stick concept to large commercial plant application is presented, with an evaluation of scaleup limitations, transient effects, and system design implications.

  3. Concussion among Swedish elite ice hockey players.

    PubMed Central

    Tegner, Y; Lorentzon, R

    1996-01-01

    OBJECTIVE: To evaluate the frequency of concussion in Swedish ice hockey and to establish a uniform grading and treatment model for concussions of different severity. METHODS: Frequency of concussion was investigated in two studies, one retrospective and one prospective. In the retrospective study, all Swedish elite ice hockey players (n = 265) were asked to answer a questionnaire on the number and treatment of previous concussions. Only concussions diagnosed by a doctor were recorded. The questionnaire was completed by 227 players (86%). In the prospective study, all injuries including concussions occurring during game and practice in the Swedish Elite League (n = 12 teams) were recorded during four years. The causes of injury, referees judgements, diagnosis, treatment, and time absent from ice hockey were registered on special cards. RESULTS: In the retrospective study, 51 out of 227 players (22%) in the Swedish Elite League reported at least one concussion. In the prospective study, 52 concussions were reported. The incidence of a concussion is at least one concussion every year/team or a yearly risk of about 5% for a player to sustain a concussion. Most concussions occurred during league play (81%). Body contact (checking or boarding) was the most common cause of concussions. The players were absent from full training and play on a mean of 6 d. CONCLUSIONS: As this injury is potentially dangerous it must be treated seriously according to a simple treatment model presented. In cases of repeated concussions during the same season, a longer period of time away from play is suggested. In players who have sustained several concussions over the years a thorough medical examination including EEG, CT/MRI, and neuropsychological tests should be performed. If any of these is pathological the player should be advised to give up ice hockey. PMID:8889123

  4. Miniature Videoprobe Hockey Stick Delivery System

    SciTech Connect

    Hale, Lester R.; McMurry, Kyle M.

    1998-06-18

    The present invention is a miniature videoprobe system having a probe termination box, a strong back, and a videoprobe housing. The videoprobe system is able to obtain images from a restricted space at least as small as 0.125 inches while producing a high quality image. The strong back has a hockey stick shape with the probe termination box connecting to the top of the handle-like portion of the hockey stick and the videoprobe housing attaching to the opposite end or nose of the hockey stick shape. The videoprobe housing has a roughly arrowhead shape with two thin steel plates sandwiching the internal components there between. The internal components are connected in series to allow for a minor dimension of the videoprobe housing of 0.110 inches. The internal components include an optics train, a CCD chip, and an electronics package. An electrical signal is transmitted from the electronics package through wiring within an internal channel of the strong back to the probe termination box. The strong back has milled into it multiple internal channels for facilitating the transfer of information, items, or devices between the probe termination box and the videoprobe housing.

  5. The Ice Hockey Injury: A Case Study in Physiology

    ERIC Educational Resources Information Center

    Stephens, Phil

    2004-01-01

    A high school hockey team is playing the last of three games in one day. The game gets rough, and the star player is slammed against the boards. Injured, he is escorted off the ice. This case follows his health as it deteriorates over the next several hours. Students are presented with the hockey player's symptoms, and they use their knowledge of…

  6. 11. Photocopy of Photograph (Courtesy of the Detroit Hockey Club, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Photocopy of Photograph (Courtesy of the Detroit Hockey Club, Detroit, Michigan). GROUNDBREAKING FOR ADDITION, JUNE 23, 1965. Left Sid Abel, Genral Manager of the Detroit Hockey Club Center - Jerome Cavanaugh, Mayor, City of Detroit Right - Nick Landis, General Manager of the Olympia Stadium - Olympia Arena, 5920 Grand River Avenue, Detroit, MI

  7. Submarine Groundwater Discharge as a Source of Mercury in the Bay of Puck, the Southern Baltic Sea.

    PubMed

    Szymczycha, Beata; Miotk, Michał; Pempkowiak, Janusz

    2013-06-01

    Both groundwater flow and mercury concentrations in pore water and seawater were quantified in the groundwater seeping site of the Bay of Puck, southern Baltic Sea. Total dissolved mercury (HgTD) in pore water ranged from 0.51 to 4.90 ng l(-1). Seawater samples were characterized by elevated HgTD concentrations, ranging from 4.41 to 6.37 ng l(-1), while HgTD concentrations in groundwater samples ranged from 0.51 to 1.15 ng l(-1). High HgTD concentrations in pore water of the uppermost sediment layers were attributed to seawater intrusion into the sediment. The relationship between HgTD concentrations and salinity of pore water was non-conservative, indicating removal of dissolved mercury upon mixing seawater with groundwater. The mechanism of dissolved mercury removal was further elucidated by examining its relationships with both dissolved organic matter, dissolved manganese (Mn II), and redox potential. The flux of HgTD to the Bay of Puck was estimated to be 18.9 ± 6.3 g year(-1). The submarine groundwater discharge-derived mercury load is substantially smaller than atmospheric deposition and riverine discharge to the Bay of Puck. Thus, groundwater is a factor that dilutes the mercury concentrations in pore water and, as a result, dilutes the mercury concentrations in the water column.

  8. PUCK: An Automated Prompting System for Smart Environments: Towards achieving automated prompting; Challenges involved.

    PubMed

    Das, Barnan; Cook, Diane J; Schmitter-Edgecombe, Maureen; Seelye, Adriana M

    2012-10-01

    The growth in popularity of smart environments has been quite steep in the last decade and so has the demand for smart health assistance systems. A smart home-based prompting system can enhance these technologies to deliver in-home interventions to users for timely reminders or brief instructions describing the way a task should be done for successful completion. This technology is in high demand given the desire of people who have physical or cognitive limitations to live independently in their homes. In this paper, with the introduction of the "PUCK" prompting system, we take an approach to automate prompting-based interventions without any predefined rule sets or user feedback. Unlike other approaches, we use simple off-the-shelf sensors and learn the timing for prompts based on real data that is collected with volunteer participants in our smart home test bed. The data mining approaches taken to solve this problem come with the challenge of an imbalanced class distribution that occurs naturally in the data. We propose a variant of an existing sampling technique, SMOTE, to deal with the class imbalance problem. To validate the approach, a comparative analysis with Cost Sensitive Learning is performed.

  9. Effect of heat exposure on thermoregulation and hockey-specific response time in field hockey goalkeepers.

    PubMed

    Malan, Marcelle; Dawson, Brian; Goodman, Carmel; Peeling, Peter

    2010-05-01

    This study examined the thermoregulatory responses in field hockey goalkeepers during games (Part A), and assessed the effect of heat stress on hockey-specific response time (Part B). In Part A, core temperature (T(c)), skin temperature (T(sk)), body mass, fluid consumption and heart rate (HR) responses of six goalkeepers during two premier level club games in the Western Australian (winter) hockey season were recorded. Part B assessed the same measures, plus a response time test on four goalkeepers playing a simulated game inside a climate chamber in cool (COOL: 20 degrees C, 40% RH) and hot (HOT: 35 degrees C, 40% RH) conditions. In Part A, the mean (+/-SD) T(c) and T(sk) measured in games was 38.49+/-0.20 degrees C and 34.99+/-0.99 degrees C, with increases from baseline of 1.34+/-0.19 degrees C and 1.08+/-0.30 degrees C, respectively. Most of the increase in T(c) resulted from the pre-game warm-up. In Part B, T(c) and T(sk) only increased significantly (p<0.05) from baseline in the HOT condition (0.62+/-0.18 degrees C and 1.61+/-0.82 degrees C, respectively). Response time was significantly slower (0.87+/-0.14s, p<0.01) after heat exposure, compared to COOL (0.75+/-0.15s), but the number of correct responses was not affected. For optimal performance, careful attention should be given to strategies to limit T(c) increases in field hockey goalkeepers during matches.

  10. 14. Photocopy of Photograph (Courtesy of the Detroit Hockey Club, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Photocopy of Photograph (Courtesy of the Detroit Hockey Club, Detroit, Michigan). AERIAL VIEW OF OLYMPIA ARENA, LOOKING NORTH, FEBRUARY 9, 1969. - Olympia Arena, 5920 Grand River Avenue, Detroit, MI

  11. Incidence of Concussion in Youth Ice Hockey Players

    PubMed Central

    Elbin, R.J.; Sufrinko, Alicia; Dakan, Scott; Bookwalter, Kylie; Price, Ali; Meehan, William P.; Collins, Michael W.

    2016-01-01

    BACKGROUND: Ice hockey is a fast-paced collision sport that entails both intentional (ie, body checking) and incidental contact that may involve the head. The objective of this study was to determine the incidence of concussions in relation to games/practices and age among competition-level youth ice hockey players (ages 12–18 years). METHODS: Participants included 397 youth ice hockey players from Western Pennsylvania; Boston, Massachusetts; and Birmingham, Alabama, during the 2012–2013 and 2013–2014 youth ice hockey seasons. Incidence rates (IRs) and incidence rate ratios (IRRs) of concussion were calculated for games/practices and age groups. RESULTS: A total of 23 369 (12 784 practice/10 585 game) athletic exposures (AEs) involving 37 medically diagnosed concussions occurred. More than 40% of concussions involved illegal contact. The combined IR for games and practices was 1.58 concussions per 1000 AEs. The IRR was 2.86 times (95% confidence interval 0.68–4.42) higher during games (2.49 per 1000 AEs) than practices (1.04 per 1000 AEs). CONCLUSIONS: The overall IR for concussion in youth ice hockey was comparable to those reported in other youth collision sports. The game-to-practice IRR was lower than previously reported in ice hockey and other youth sports, although more concussions per exposure occurred in games compared with practices. Younger players had a higher rate of concussions than older players. PMID:26746405

  12. Personal food systems of male college hockey players.

    PubMed

    Smart, L R; Bisogni, C A

    2001-08-01

    This study sought to improve the understanding of processes involved in food choice and dietary change by examining how members of a college men's ice hockey team experienced the multiple factors influencing their food choices. The study employed a theory-guided, grounded-theory approach, participant observation, and open-ended interviews with ten team members. Field notes and transcripts were analysed using the constant comparative method. Going to college and playing hockey involved adjusting to new food and athletic environments, increased personal responsibility for food choices, and new meanings for food and eating. Players viewed hockey, health, and taste as major determinants of their food practices. Hockey meant structured schedules, a social network, and performance expectations. Health meant "feeling good" for hockey, having a lean body composition, and a desirable body image. Low-fat foods were viewed generally as healthy, but as not providing taste satisfaction or reward. Players' food practices cycled through four phases over the year according to the changing meanings and importance of hockey, health, and taste. The findings advance the concept of personal food system to represent the way that a person constructs the options, barriers, trade-offs, rules, and routines in food choice in response to how s/he views his/her relationships with food and the environment.

  13. Automatic acquisition of motion trajectories: tracking hockey players

    NASA Astrophysics Data System (ADS)

    Okuma, Kenji; Little, James J.; Lowe, David

    2003-12-01

    Computer systems that have the capability of analyzing complex and dynamic scenes play an essential role in video annotation. Scenes can be complex in such a way that there are many cluttered objects with different colors, shapes and sizes, and can be dynamic with multiple interacting moving objects and a constantly changing background. In reality, there are many scenes that are complex, dynamic, and challenging enough for computers to describe. These scenes include games of sports, air traffic, car traffic, street intersections, and cloud transformations. Our research is about the challenge of inventing a descriptive computer system that analyzes scenes of hockey games where multiple moving players interact with each other on a constantly moving background due to camera motions. Ultimately, such a computer system should be able to acquire reliable data by extracting the players" motion as their trajectories, querying them by analyzing the descriptive information of data, and predict the motions of some hockey players based on the result of the query. Among these three major aspects of the system, we primarily focus on visual information of the scenes, that is, how to automatically acquire motion trajectories of hockey players from video. More accurately, we automatically analyze the hockey scenes by estimating parameters (i.e., pan, tilt, and zoom) of the broadcast cameras, tracking hockey players in those scenes, and constructing a visual description of the data by displaying trajectories of those players. Many technical problems in vision such as fast and unpredictable players' motions and rapid camera motions make our challenge worth tackling. To the best of our knowledge, there have not been any automatic video annotation systems for hockey developed in the past. Although there are many obstacles to overcome, our efforts and accomplishments would hopefully establish the infrastructure of the automatic hockey annotation system and become a milestone for

  14. Media Coverage of Boys' and Girls' High School Ice Hockey in Minnesota.

    ERIC Educational Resources Information Center

    Woodcock, Amy Terhaar

    1995-01-01

    Reports a study that compared the newspaper coverage of girls' and boys' high school hockey teams in Minnesota from November 1994 to March 1995. Researchers coded each newspaper article for sex, length, and photo types. Results indicated that boys' high school hockey received much more newspaper coverage than girls' high school hockey. (SM)

  15. Gender, Sport, and the Construction of Community: A Case Study from Women's Ice Hockey.

    ERIC Educational Resources Information Center

    Theberge, Nancy

    1995-01-01

    Examines the construction of community on a women's ice hockey team, using data from fieldwork and interviews with one Canadian team. Results indicated that the locker room provided a space where players came together as hockey players and women. A common focus on hockey united the diverse group. (SM)

  16. Measurement of head impacts in youth ice hockey players.

    PubMed

    Reed, N; Taha, T; Keightley, M; Duggan, C; McAuliffe, J; Cubos, J; Baker, J; Faught, B; McPherson, M; Montelpare, W

    2010-11-01

    Despite growing interest in the biomechanical mechanisms of sports-related concussion, ice hockey and the youth sport population has not been studied extensively. The purpose of this pilot study was: 1) to describe the biomechanical measures of head impacts in youth minor ice hockey players; and, 2) to investigate the influence of player and game characteristics on the number and magnitude of head impacts. Data was collected from 13 players from a single competitive Bantam boy's (ages 13-14 years) AAA ice hockey team using telemetric accelerometers implanted within the players' helmets at 27 ice hockey games. The average linear acceleration, rotational acceleration, Gadd Severity Index and Head Injury Criterion of head impacts were recorded. A significantly higher number of head impacts per player per game were found for wingers when compared to centre and defense player positions (df=355, t=3.087, p=0.00218) and for tournament games when compared to regular season and playoff games (df=355, t=2.641, p=0.086). A significant difference in rotational acceleration according to player position (F2,1812=4.9551, p=0.0071) was found. This study is an initial step towards a greater understanding of head impacts in youth ice hockey.

  17. Are There Differences in Ice Hockey Injuries Between Sexes?

    PubMed Central

    MacCormick, Lauren; Best, Thomas M.

    2014-01-01

    Background: Men’s ice hockey allows for body checking, and women’s ice hockey prohibits it. Studies have reported injury data on both sexes, but no systematic reviews have compared the injury patterns between male and female ice hockey players. Hypothesis: Men’s and women’s ice hockey would have different types of injuries, and this difference would extend across the different age groups and levels of play. Study Design: Systematic review; Level of evidence, 4. Methods: Three databases, 3 scientific journals, and selected bibliographies were searched to identify articles relevant to this study. Articles were further screened by the use of predetermined inclusion and exclusion criteria. Twenty-two studies met these criteria and were subsequently reviewed. Results: Men sustained higher rates of injuries than women at all age levels, and both sexes sustained at least twice as many injuries in games than practices. Both sexes sustained most of their injuries from player contact. Men and women in college sustained most injuries to the head and face, and women suffered from higher percentages of concussion. At all ages and levels of play, men had higher rates of upper extremity injuries (shoulder), while women were found to sustain more injuries to the lower extremity (thigh, knee). Conclusion: Although findings showed men sustaining higher rates of injuries than women, the predominant mechanism of player contact was the same. The most common locations and types of injuries in female ice hockey players are comparable to other sports played by women, and similar interventions could offer protection against injury. Clinical Relevance: Further studies that report injury data for women playing ice hockey at all levels will assist in understanding what prevention strategies should be implemented. PMID:26535265

  18. Increasing task complexity and ice hockey skills of youth athletes.

    PubMed

    Fait, Philippe E; McFadyen, Bradford J; Zabjek, Karl; Reed, Nick; Taha, Tim; Keightley, Michelle

    2011-02-01

    The objective of this pilot study was to investigate the effects on cognitive performance of progressively adding tasks specific to ice hockey (skating, stick handling, and obstacle avoidance) during a visual interference task (Stroop Color Word Test-interference condition). In addition, the effects on locomotor performance of progressively adding tasks of stickhandling, visual interference, and obstacle avoidance related to maximal skating speed and minimal obstacle clearance were investigated in eight male athletes ages 10 to 12 years. Results revealed decreased performance on both cognitive and physical measures with increased task complexity, suggesting that adding complexity to an environment influences hockey skill performance.

  19. Relationship of physical fitness test results and hockey playing potential in elite-level ice hockey players.

    PubMed

    Burr, Jaime F; Jamnik, Roni K; Baker, Joseph; Macpherson, Alison; Gledhill, Norman; McGuire, E J

    2008-09-01

    The primary purpose of this study was to determine the fitness variables with the highest capability for predicting hockey playing potential at the elite level as determined by entry draft selection order. We also examined the differences associated with the predictive abilities of the test components among playing positions. The secondary purpose of this study was to update the physiological profile of contemporary hockey players including positional differences. Fitness test results conducted by our laboratory at the National Hockey League Entry Draft combine were compared with draft selection order on a total of 853 players. Regression models revealed peak anaerobic power output to be important for higher draft round selection in all positions; however, the degree of importance of this measurement varied with playing position. The body index, which is a composite score of height, lean mass, and muscular development, was similarly important in all models, with differing influence by position. Removal of the goalies' data increased predictive capacity, suggesting that talent identification using physical fitness testing of this sort may be more appropriate for skating players. Standing long jump was identified as a significant predictor variable for forwards and defense and could be a useful surrogate for assessing overall hockey potential. Significant differences exist between the physiological profiles of current players based on playing position. There are also positional differences in the relative importance of anthropometric and fitness measures of off-ice hockey tests in relation to draft order. Physical fitness measures and anthropometric data are valuable in helping predict hockey playing potential. Emphasis on anthropometry should be used when comparing elite-level forwards, whereas peak anaerobic power and fatigue rate are more useful for differentiating between defense.

  20. A Hockey Night in Canada: An Imagined Conversation between Theorists

    ERIC Educational Resources Information Center

    Fogel, Curtis

    2010-01-01

    In this paper, various methodological issues surrounding the sociological study of sport are explored. Through an imagined dialogue between two graduate students at a hockey game, this work brings together three divergent approaches to social enquiry: Positivist Grounded Theory, Constructivist Grounded Theory, and Actor-Network Theory. This paper…

  1. Injuries in Youth Hockey. On-Ice Emergency Care.

    ERIC Educational Resources Information Center

    Blanchard, Bradford M.; Castaldi, Cosmo R.

    1991-01-01

    Reviews the nature and frequency of injuries in youth hockey (which range from musculoskeletal injuries to life-threatening emergencies). Overall injury rates have decreased, but there is an increase in head, neck, and spine injuries. Those injuries that are serious demand prompt, skillful attention. A comprehensive format for on-ice management is…

  2. Occupational and recreational noise exposure from indoor arena hockey games.

    PubMed

    Cranston, Cory J; Brazile, William J; Sandfort, Delvin R; Gotshall, Robert W

    2013-01-01

    Occupational and recreational noise exposures were evaluated at two sporting arenas hosting collegiate hockey games (Venue 1) and semi-professional hockey (Venue 2). A total of 54 personal noise dosimetry samples were taken over the course of seven home hockey games: 15 workers and 9 fans at Venue 1, and 19 workers and 11 fans at Venue 2. None of the sampled workers were overexposed to noise based on Occupational Safety and Health Administration criteria. However, 40% and 57% of workers at Venue 1 and 33% and 91% of fans at Venue 2 were overexposed based on ACGIH noise exposure criteria. Noise exposures for fans were significantly different between venues, but worker noise exposures between venues were not significantly different. In addition, extensive area noise monitoring was conducted at each venue to further characterize the stadium noise on a location-by-location basis. Mean equivalent sound pressure levels ranged from 81 to 96 dBA at Venue 1 and from 85 to 97 dBA at Venue 2. Mean noise peak levels ranged from 105 to 124 dBA at Venue 1, and from 110 to 117 dBA at Venue 2. These data reflect the potential for overexposure at indoor hockey events and are useful in characterizing occupational noise exposure of indoor arena support staff and may also provide a foundation for future noise control research in indoor sports arenas.

  3. Asymmetry in body composition in female hockey players.

    PubMed

    Krzykała, M; Leszczyński, P

    2015-08-01

    The aim of the study was to determine if a sport in which one side of the body is dominant, like field hockey, influences regional body composition and bone mineral density (BMD) distribution in particular body segments, and whether the sporting level is a determining factor. Dual energy X-ray absorptiometry (DXA) method (Lunar Prodigy Advance; General Electric, Madison, USA) with the whole body scan was used to measure bone mineral density, fat mass and lean mass in 31 female field hockey players divided according to their sporting level. The morphological asymmetry level was assessed between two body sides and body segments in athletes from the National Team (n=17) and from the Youth Team (n=14) separately and between groups. Bone mineral density in the lower extremity and of the trunk was significantly asymmetric in favor of the left side in the National Team. In the case of the Youth Team, only the trunk BMD indicated clear left-right difference with left side dominance. Both the lean mass and fat mass values were relatively higher on the left side of all body segments and it related to both analyzed groups of athletes. The present study shows that playing field hockey contributes to laterality in body composition and BMD and that the sporting level is a determining factor. In most cases the left side dominated. A greater asymmetry level was observed in more experienced female field hockey players.

  4. Expert-novice differences in brain function of field hockey players.

    PubMed

    Wimshurst, Z L; Sowden, P T; Wright, M

    2016-02-19

    The aims of this study were to use functional magnetic resonance imaging to examine the neural bases for perceptual-cognitive superiority in a hockey anticipation task. Thirty participants (15 hockey players, 15 non-hockey players) lay in an MRI scanner while performing a video-based task in which they predicted the direction of an oncoming shot in either a hockey or a badminton scenario. Video clips were temporally occluded either 160 ms before the shot was made or 60 ms after the ball/shuttle left the stick/racquet. Behavioral data showed a significant hockey expertise×video-type interaction in which hockey experts were superior to novices with hockey clips but there were no significant differences with badminton clips. The imaging data on the other hand showed a significant main effect of hockey expertise and of video type (hockey vs. badminton), but the expertise×video-type interaction did not survive either a whole-brain or a small-volume correction for multiple comparisons. Further analysis of the expertise main effect revealed that when watching hockey clips, experts showed greater activation in the rostral inferior parietal lobule, which has been associated with an action observation network, and greater activation than novices in Brodmann areas 17 and 18 and middle frontal gyrus when watching badminton videos. The results provide partial support both for domain-specific and domain-general expertise effects in an action anticipation task.

  5. In situ calibration of the Gamma Reaction History instrument using reference samples ("pucks") for areal density measurements

    NASA Astrophysics Data System (ADS)

    Hoffman, N. M.; Herrmann, H. W.; Kim, Y. H.; Hsu, H. H.; Horsfield, C. J.; Rubery, M. S.; Wilson, D. C.; Stoeffl, W. W.; Young, C. S.; Mack, J. M.; Miller, E. K.; Grafil, E.; Evans, S. C.; Sedillo, T. J.; Glebov, V. Yu.; Duffy, T.

    2013-11-01

    The introduction of a sample of carbon, for example a disk or "puck", near an imploding DT-filled capsule creates a source of 12C gamma rays that can serve as a reference for calibrating the response of the Gamma Reaction History (GRH) detector [1]. Such calibration is important in the measurement of ablator areal density ⟨ρR⟩abl in plastic-ablator DT-filled capsules at OMEGA [2], by allowing ⟨ρR⟩abl to be inferred as a function of ratios of signals rather than from absolute measurements of signal magnitudes. Systematic uncertainties in signal measurements and detector responses therefore cancel, permitting more accurate measurements of ⟨ρR⟩abl.

  6. Injury data of major international field hockey tournaments

    PubMed Central

    Theilen, Till-Martin; Mueller-Eising, Wiebke; Wefers Bettink, Peter; Rolle, Udo

    2016-01-01

    Background Detailed injury data are not available for international tournaments in field hockey. We investigated the epidemiology of field hockey injuries during major International Hockey Federation (Fédération Internationale de Hockey, FIH) tournaments in 2013. Materials and methods FIH injury reports were used for data collection. All major FIH tournaments for women (n=5) and men (n=11) in 2013 were included. The main focus of this study was to assess the pattern, time, site on the pitch, body site and mechanism of each of the injuries. We calculated the average number of injuries per match and the number of injuries per 1000 player match hours. Results The average number of injuries was 0.7 (95% CI 0.5 to 1.0) per match in women's tournaments and 1.2 (95% CI 0.8 to 1.7) per match in men's tournaments. The number of injuries per 1000 player match hours ranged from 23.4 to 44.2 (average 29.1; 95% CI 18.6 to 39.7) in women and 20.8 to 90.9 (average 48.3; 95% CI 30.9 to 65.8) in men. Most injuries occurred in the circle (n=25, 50%, in women, n=95, 51%, in men). The rate of injuries increased after the first quarter. Injuries to the head and face (n=20, 40%) were most common in women. The head/face (n=51, 27%) and the thigh/knee (n=52, 28%) were equally affected in men. The ball caused the most injuries, followed by the stick, collisions and tripping/falling. There were no deaths or injuries that required hospital treatment in the entire cohort. Summary Field hockey has a low incidence of acute injuries during competition. PMID:26246418

  7. Hypothenar hammer syndrome from ice hockey stick-handling.

    PubMed

    Zayed, Mohamed A; McDonald, Joey; Tittley, Jacques G

    2013-11-01

    Ulnar artery thrombosis and hypothenar hammer syndrome are rare vascular complications that could potentially occur with repeated blows or trauma to the hand. Although initially reported as an occupational hazard among laborers and craftsmen, it has been observed more recently among recreationalists and athletes. Until now, it has never been reported as a complication in ice hockey players. In this case report, a 26-year-old Canadian professional ice hockey player presented with acute dominant right hand paleness, coolness, and pain with hand use. The patient used a wooden hockey stick with a large knob of tape at the end of the handle, which he regularly gripped in the palm of his right hand to help with face-offs and general stick-handling. Sonographic evaluation demonstrated no arterial flow in the distal right ulnar artery distribution, and ulnar artery occlusion with no aneurysmal degeneration was confirmed by magnetic resonance angiogram. Intraarterial thrombolytic therapy was initiated, and subsequent serial angiograms demonstrated significant improvement in distal ulnar artery flow as well as recanalization of right hand deep palmar arch and digital arteries. The patient's symptoms resolved, and he was maintained on therapeutic anticoagulation for 3 months prior to returning to playing ice hockey professionally, but with a padded glove and no tape knob at the handle tip. This case highlights a unique presentation of hockey stick-handling causing ulnar artery thrombosis that was likely from repeated palmar hypothenar trauma. Appropriate diagnostic imaging, early intraarterial thrombolysis, and postoperative surveillance and follow-up were crucial for the successful outcome in this patient.

  8. Position Statement. Violence and injury in ice hockey.

    PubMed

    Juhn, Mark S; Brolinson, Per Gunnar; Duffey, Timothy; Stockard, Alan; Vangelos, Zenos A; Emaus, Erik; Maddox, Matthew; Boyajian, Lori; Henehan, Michael

    2002-01-01

    Ice hockey is a sport enjoyed by many men and women at the spectator and participant level. It is played with high intensity and often involves body contact. Although the women's games is far from injury free, it is the men's game that has drawn criticism for excessive violence. Much attention has been drawn to the serious injuries that have occurred in ice hockey, specifically spinal injuries, concussions, and eye injuries. Many such injuries are the result of illegal and violent acts such as checking from behind or a deliberate high stick. Because of this, some medical organizations have called for changes in the sport, such as minimum age requirements for body-checking. As a practical matter such changes are unlikely to be accepted by hockey governing boards. Many of those involved in the sport consider body-checking a fundamental component of the game. Furthermore, a distinction needs to be made between any kind of injury and a serious, catastrophic injury. For example, although a recent study found that body-checking accounted for up to 38% of ice hockey injuries, none were of the catastrophic type. With respect to catastrophic injuries such as spinal cord trauma or a blinded eye, legal body-checking accounts for significantly less than illegal body-checking (e.g., checking from behind) or violent stick work. To reduce serious injury in ice hockey, we offer 10 recommendations, key among them automatic game suspensions for certain rules violations, and recognition of the coach as the most important figure in promoting a clean, safe game.

  9. Shock Separation and Dead-Zone Formation from Detonations in an Internal Air-Well Geometry

    NASA Astrophysics Data System (ADS)

    Molitoris, John; Andreski, Henry; Garza, Raul; Batteux, Jan; Vitello, Peter; Souers, Clark

    2007-06-01

    Here we report on measurements of dead-zone formation due to shock separation from detonations attempting to corner-turn in an internal air-well geometry. This geometry is also known as a ``hockey-puck'' configuration. These measurements were performed on detonations in LX-17 and PBX9502 using time sequence radiography to image the event with surface contact timing pins as an additional diagnostic. In addition to an open corner in the high-explosive component we also examined the effects of steel defining the corner. In these experiments we find a long lived dead-zone consisting of shocked explosive that persists to very late times. Data and numerical modeling will be presented in addition to a comparison with previous work using an external air well. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

  10. Aerobic Development of Elite Youth Ice Hockey Players.

    PubMed

    Leiter, Jeff R; Cordingley, Dean M; MacDonald, Peter B

    2015-11-01

    Ice hockey is a physiologically complex sport requiring aerobic and anaerobic energy metabolism. College and professional teams often test aerobic fitness; however, there is a paucity of information regarding aerobic fitness of elite youth players. Without this knowledge, training of youth athletes to meet the standards of older age groups and higher levels of hockey may be random, inefficient, and or effective. Therefore, the purpose of this study was to determine the aerobic fitness of elite youth hockey players. A retrospective database review was performed for 200 male AAA hockey players between the ages of 13 and 17 (age, 14.4 ± 1.2 years; height, 174.3 ± 8.5 cm; body mass, 67.2 ± 11.5 kg; body fat, 9.8 ± 3.5%) before the 2012-13 season. All subjects performed a graded exercise test on a cycle ergometer, whereas expired air was collected by either a Parvo Medics TrueOne 2400 or a CareFusion Oxycon Mobile metabolic cart to determine maximal oxygen consumption (V[Combining Dot Above]O2max). Body mass, absolute V[Combining Dot Above]O2max, and the power output achieved during the last completed stage increased in successive age groups from age 13 to 15 years (p ≤ 0.05). Ventilatory threshold (VT) expressed as a percentage of V[Combining Dot Above]O2max and the heart rate (HR) at which VT occurred decreased between the ages of 13 and 14 years (p ≤ 0.05), whereas the V[Combining Dot Above]O2 at which VT occurred increased from the age of 14-15 years. There were no changes in relative V[Combining Dot Above]O2max or HRmax between any successive age groups. The aerobic fitness levels of elite youth ice hockey players increased as players age and mature physically and physiologically. However, aerobic fitness increased to a lesser extent at older ages. This information has the potential to influence off-season training and maximize the aerobic fitness of elite amateur hockey players, so that these players can meet standards set by advanced elite age groups.

  11. Lumbar facet fracture in an adolescent ice hockey player.

    PubMed

    Shaffer, W O; Taylor, M R; Sundaram, M

    1999-11-01

    A 14-year-old boy was checked hard as he was winding up to shoot in an ice hockey game. He experienced low-back pain during the game but when examined later for complaints of pain and fever, he denied trauma. Plain x-rays were normal, but a bone scan showed increased uptake at L-3. MRI evaluation revealed a lumbar mass; a CT scan showed the mass to be a hematoma and edema secondary to a facet fracture. Acute severe back pain in a hockey player should prompt a careful history and a search for musculoskeletal injury. When trauma in the lumbar spine is suspected and plain radiographs are nondiagnostic, CT scans are more precise than MRI for diagnosing injury.

  12. Effects of multiple concussions on retired national hockey league players.

    PubMed

    Caron, Jeffrey G; Bloom, Gordon A; Johnston, Karen M; Sabiston, Catherine M

    2013-04-01

    The purpose of this study was to understand the meanings and lived experiences of multiple concussions in professional hockey players using hermeneutic, idiographic, and inductive approaches within an interpretative phenomenological analysis. The interviewer was an athlete who had suffered multiple concussions, and the interviewees were five former National Hockey League athletes who had retired due to medically diagnosed concussions suffered during their careers. The men discussed the physical and psychological symptoms they experienced as a result of their concussions and how the symptoms affected their professional careers, personal relationships, and quality of life. The former professional athletes related these symptoms to the turmoil that is ever present in their lives. These findings are of interest to athletes, coaches, sport administrators, family members, sport psychology practitioners, and medical professionals, as they highlight the severity of short- and long-term effects of concussions.

  13. National survey of spinal injuries in hockey players.

    PubMed Central

    Tator, C. H.; Edmonds, V. E.

    1984-01-01

    There has been an alarming increase in the number of spinal injuries in hockey players. Between 1976 and 1983, 42 were reported to the Committee on Prevention of Spinal Injuries due to Hockey. The median age of the injured players was 17 years. Of the 42 players 28 had spinal cord injuries, and 17 of them had complete paralysis below the vertebral level of the injury. Strikes from behind and collisions with the boards were common mechanisms of injury. Many of the players had suffered a burst fracture of the cervical spine following a blow to the top of the helmet when the neck was slightly flexed. The committee studied a number of possible etiologic factors and made several recommendations regarding prevention. League officials, coaches, players and equipment manufacturers can all play a role in prevention. Images Fig. 1 Fig. 2 PMID:6704840

  14. [Hemodynamic Status of Prepubertal and Pubertal Hockey Players].

    PubMed

    Shayhelislamova, M V; Sitdikov, F G; Zefirov, T L; Dikopolskaya, N B

    2015-01-01

    The hemodynamic status of 11-15-year-old hockey players depending on their age and puberty stage were studied and compared with hemodynamic parameters of the control group. It was found that regular muscle training has a dominant effect on the functional state of cardiovascular system (CVS) in prepuberty and puberty. It was proved that in hockey players a decrease in the heart rate (H R) and an increase in the stroke volume (SV) result in a significant increase in systolic blood pressure (SBP) at the age of 11-14 years and a progressive increase in total peripheral vascular resistance (PVR), in contrast to significantly lower values in the control group. The urgent adaptation of CVS to graduated physical activities at the age of 11-13 years leads to an enhancement of vascular spasmodic reactions while SV remains constant. It was found that in adolescent hockey players have consistently high SV and SBP; at the same time, maximal values of HR, cardiac output (CO) and diastolic blood pressure (DBP) were observed at the stages I and II of the puberty period; then, at the stage III, these parameters decrease. I n the control group, hymodinamic status changed in an opposite way. This may be an evidence of the stress effect of physical activities which results in the adaptive reactions of CVS rather than reactions typical of the puberty period.

  15. Prevalence of Vitamin D Insufficiency in Professional Hockey Players

    PubMed Central

    Mehran, Nima; Schulz, Brian M.; Neri, Brian R.; Robertson, William J.; Limpisvasti, Orr

    2016-01-01

    Background: Vitamin D is a fat-soluble hormone that plays a role in bone health, muscle function, and athletic performance. Studies have shown that low levels of vitamin D can lead to slower muscle recovery and function, increased rates of stress fractures, and even poorer athletic performance. Insufficient vitamin D levels have been demonstrated in professional basketball and football players, however, there have been no studies to date reviewing vitamin D insufficiency in professional hockey players. Purpose/Hypothesis: The purpose of this study was to perform a cross-sectional review to determine the prevalence of vitamin D deficiency and insufficiency in professional hockey players. The hypothesis was that there would be a high percentage of players with vitamin D insufficiency. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The preseason serum 25-hydroxy (OH) vitamin D laboratory test results of 105 professional hockey players were retrospectively reviewed. All players on 3 National Hockey League (NHL) teams were included. Player parameters evaluated included age, height, weight, body mass index, and 25(OH) vitamin D level. Players were divided into 4 groups based on serum vitamin D levels: deficient (<20 ng/mL), insufficient (20-31.9 ng/mL), sufficient (≥32 ng/mL), and ideal (≥40 ng/mL). Descriptive statistics were performed, in addition to 2-group and 3-group comparisons. Results: The average 25(OH) vitamin D level of 105 players was 45.8 ± 13.7 ng/mL (range, 24-108 ng/mL). No players in the study were considered deficient. A total of 14 players (13.3%) were considered insufficient, while 91 players (86.7%) were considered sufficient. However, only 68 players (64.8%) were considered ideal. When comparing groups, athletes with sufficient vitamin D levels were older than athletes with insufficient vitamin D levels (25.9 vs 23.1 years; P = .018). All other player parameters demonstrated no significant difference between groups

  16. "No Fear Comes": Adolescent Girls, Ice Hockey, and the Embodiment of Gender.

    ERIC Educational Resources Information Center

    Theberge, Nancy

    2003-01-01

    Examined the relationship between gender, physicality, and embodiment among Canadian adolescent girls who played ice hockey. Interview data indicated that the girls emphasized the importance of being aggressive (fearless in use of the body). Players understood that contrasts between men's hockey (more physical and aggressive) and women's hockey…

  17. THE COMPETITIVE DEMANDS OF ELITE MALE RINK HOCKEY

    PubMed Central

    Del Valle, M.E.; Egocheaga, J.; Linnamo, V.; Fernández, A.

    2013-01-01

    The aim of this study was to simulate the activity pattern of rink hockey by designing a specific skate test (ST) to study the energy expenditure and metabolic responses to this intermittent high-intensity exercise and extrapolate the results from the test to competition. Six rink hockey players performed, in three phases, the 20-metre multi-stage shuttle roller skate test, a tournament match and the ST. Heart rate was monitored in all three phases. Blood lactate, oxygen consumption, ventilation and respiratory exchange ratio were also recorded during the ST. Peak HR was 190.7±7.2 beats · min−1. There were no differences in peak HR between the three tests. Mean HR was similar between the ST and the match (86% and 87% of HRmax, respectively). Peak and mean ventilation averaged 111.0±8.8 L · min−1 and 70.3±14.0 L · min−1 (60% of VEmax), respectively. VO2max was 56.3±8.4 mL · kg−1 · min−1, and mean oxygen consumption was 40.9±7.9 mL · kg−1 · min−1 (70% of VO2max). Maximum blood lactate concentration was 7.2±1.3 mmol · L-1. ST yielded an energy expenditure of 899.1±232.9 kJ, and energy power was 59.9±15.5 kJ · min−1. These findings suggest that the ST is suitable for estimating the physiological demands of competitive rink hockey, which places a heavy demand on the aerobic and anaerobic systems, and requires high energy consumption. PMID:24744488

  18. PHYSICAL THERAPY MANAGEMENT OF ICE HOCKEY ATHLETES: FROM THE RINK TO THE CLINIC AND BACK

    PubMed Central

    Davenport, Todd E.

    2016-01-01

    ABSTRACT Background The increasing number of athletes playing hockey compels rehabilitation professionals working in orthopedic and sports settings to understand the unique functional demands of ice hockey and the patterns of injuries they may promote. Purpose The purpose of this clinical perspective is to: (1) discuss the functional implications of different positions and age levels on injury prevalence within the sport; (2) summarize the seven most common injuries sustained by ice hockey athletes; and (3) present a conceptual model for the clinical management and prevention of these injuries by rehabilitation professionals. Methods A narrative review and synthesis was conducted of currently available literature on prevalence, etiology, rehabilitative intervention, prognosis, and prevention of ice hockey injuries. Results Research evidence is available to support the prevalence of injuries sustained while participating in ice hockey, as well as the most effective clinical treatment protocols to treat them. Most of the existing protocols are based on clinical and sports experience with incorporation of scientific data. Conclusion This clinical commentary reviews the current concepts of ice hockey injury care and prevention, based on scientific information regarding the incidence, mechanism, rehabilitation protocols, prognosis, and prevention of injuries. Science-based, patient-centered reasoning is integral to provide the highest quality of rehabilitative and preventative care for ice hockey athletes by physical therapists. Level of Evidence 5 PMID:27274432

  19. Evaluation, management and prevention of lower extremity youth ice hockey injuries

    PubMed Central

    Popkin, Charles A; Schulz, Brian M; Park, Caroline N; Bottiglieri, Thomas S; Lynch, T Sean

    2016-01-01

    Ice hockey is a fast-paced sport played by increasing numbers of children and adolescents in North America and around the world. Requiring a unique blend of skill, finesse, power and teamwork, ice hockey can become a lifelong recreational activity. Despite the rising popularity of the sport, there is ongoing concern about the high frequency of musculoskeletal injury associated with participation in ice hockey. Injury rates in ice hockey are among the highest in all competitive sports. Numerous research studies have been implemented to better understand the risks of injury. As a result, rule changes were adopted by the USA Hockey and Hockey Canada to raise the minimum age at which body checking is permitted to 13–14 years (Bantam level) from 11–12 years (Pee Wee). Continuing the education of coaches, parents and players on rules of safe play, and emphasizing the standards for proper equipment use are other strategies being implemented to make the game safer to play. The objective of this article was to review the evaluation, management and prevention of common lower extremity youth hockey injuries. PMID:27920584

  20. Evaluation, management and prevention of lower extremity youth ice hockey injuries.

    PubMed

    Popkin, Charles A; Schulz, Brian M; Park, Caroline N; Bottiglieri, Thomas S; Lynch, T Sean

    2016-01-01

    Ice hockey is a fast-paced sport played by increasing numbers of children and adolescents in North America and around the world. Requiring a unique blend of skill, finesse, power and teamwork, ice hockey can become a lifelong recreational activity. Despite the rising popularity of the sport, there is ongoing concern about the high frequency of musculoskeletal injury associated with participation in ice hockey. Injury rates in ice hockey are among the highest in all competitive sports. Numerous research studies have been implemented to better understand the risks of injury. As a result, rule changes were adopted by the USA Hockey and Hockey Canada to raise the minimum age at which body checking is permitted to 13-14 years (Bantam level) from 11-12 years (Pee Wee). Continuing the education of coaches, parents and players on rules of safe play, and emphasizing the standards for proper equipment use are other strategies being implemented to make the game safer to play. The objective of this article was to review the evaluation, management and prevention of common lower extremity youth hockey injuries.

  1. Development of hydroacoustical techniques for the monitoring and classification of benthic habitats in Puck Bay: Modeling of acoustic waves scattering by seagrass

    NASA Astrophysics Data System (ADS)

    Raczkowska, A.; Gorska, N.

    2012-12-01

    Puck Bay is an area of high species biodiversity belonging to the Coastal Landscape Park of Baltic Sea Protected Areas (BSPA) and is also included in the list of the World Wide Fund for Nature (WWF) and covered by the protection program "Natura 2000". The underwater meadows of the Puck Bay are important for Europe's natural habitats due to their role in enhancing the productivity of marine ecosystems and providing shelter and optimal feeding conditions for many marine organisms. One of the dominant species comprising the underwater meadows of the Southern Baltic Sea is the seagrass Zostera marina. The spatial extent of underwater seagrass meadows is altered by pollution and eutrophication; therefore, to properly manage the area one must monitor its ecological state. Remote acoustic methods are useful tools for the monitoring of benthic habitats in many marine areas because they are non-invasive and allow researchers to obtain data from a large area in a short period of time. Currently there is a need to apply these methods in the Baltic Sea. Here we present an analysis of the mechanism of scattering of acoustic waves on seagrass in the Southern Baltic Sea based on the numerical modeling of acoustic wave scattering by the biological tissues of plants. The study was conducted by adapting a model developed on the basis of DWBA (Distorted Wave Born Approximation) developed by Stanton and Chu (2005) for fluid-like objects, including the characteristics of the Southern Baltic seagrass. Input data for the model, including the morphometry of seagrass leaves, their angle of inclination and the density plant cover, was obtained through the analysis of biological materials collected in the Puck Bay in the framework of a research project financed by the Polish Government (Development of hydroacoustic methods for studies of underwater meadows of Puck Bay, 6P04E 051 20). On the basis of the developed model, we have analyzed the dependence of the target strength of a single

  2. Physiological profiles of the Canadian Olympic Hockey Team (1980).

    PubMed

    Smith, D J; Quinney, H A; Steadward, R D; Wenger, H A; Sexsmith, J R

    1982-06-01

    In order to establish baseline data and to prescribe training programmes to off-set weaknesses, selected measures of aerobic fitness (VO2max), muscular power (peak torque and watt output) and performance times on-ice were collected on the Canadian Olympic Hockey Team (1980). VO2max values (54 ml. kg. min) were similar to other non-endurance athletes. Peak torque values relative to body weight in knee extension at 30 degrees and 180 degrees . s-1 (3.62 an 1.85 Nm . kg-1) were the same at low speed but lower at high speed than other selected power athletes. The on-ice performance times showed higher speed of over 180' than professional and junior level players but the speed drop-off over six repeats was greater. There were no differences between positions on these measures. These data offer a baseline from which to compare other hockey players and suggest that the aerobic fitness levels and torque outputs at high speed are not well developed.

  3. The Effect of a Complex Training Program on Skating Abilities in Ice Hockey Players

    PubMed Central

    Lee, Changyoung; Lee, Sookyung; Yoo, Jaehyun

    2014-01-01

    [Purpose] Little data exist on systemic training programs to improve skating abilities in ice hockey players. The purpose of this study was to evaluate the effectiveness of a complex training program on skating abilities in ice hockey players. [Methods] Ten male ice hockey players (training group) that engaged in 12 weeks of complex training and skating training and ten male players (control group) that only participated in 12 weeks of skating training completed on-ice skating tests including a 5 time 18 meters shuttle, t-test, Rink dash 5 times, and line drill before, during, and the training. [Results] Significant group-by-time interactions were found in all skating ability tests. [Conclusion] The complex training program intervention for 12 weeks improved their skating abilities of the ice hockey players. PMID:24764628

  4. [Profile of childrens' hockey coaches and motives of participation and resignation].

    PubMed

    Spallanzani, C

    1988-06-01

    The purpose of this study was twofold: (a) to outline a demographic profile of Quebec minor hockey coaches and (b) to identify their motives of involvement and resignation. A questionnaire was completed by 333 current coaches and by 175 former coaches from the Quebec City area. Results showed that these volunteers are very similar on all counts. They are fathers of at least one boy who is a hockey player, and they come from all socio-economic strata. They are former hockey players and are well aware of the activities of the professional teams. They perceive themselves as being competent coaches and are satisfied with their results. They highly value hockey as a means of education and perceive their own role of volunteer as being an unselfish one geared toward youth education. On the other hand, they perceive the other volunteers' involvement as being self-interested and mainly due to the child's primary participation.

  5. Reducing injury risk from body checking in boys' youth ice hockey.

    PubMed

    Brooks, Alison; Loud, Keith J; Brenner, Joel S; Demorest, Rebecca A; Halstead, Mark E; Kelly, Amanda K Weiss; Koutures, Chris G; LaBella, Cynthia R; LaBotz, Michele; Martin, Stephanie S; Moffatt, Kody

    2014-06-01

    Ice hockey is an increasingly popular sport that allows intentional collision in the form of body checking for males but not for females. There is a two- to threefold increased risk of all injury, severe injury, and concussion related to body checking at all levels of boys' youth ice hockey. The American Academy of Pediatrics reinforces the importance of stringent enforcement of rules to protect player safety as well as educational interventions to decrease unsafe tactics. To promote ice hockey as a lifelong recreational pursuit for boys, the American Academy of Pediatrics recommends the expansion of nonchecking programs and the restriction of body checking to elite levels of boys' youth ice hockey, starting no earlier than 15 years of age.

  6. Relationships to skating performance in competitive hockey players.

    PubMed

    Farlinger, Chris M; Kruisselbrink, L Darren; Fowles, Jonathon R

    2007-08-01

    The purpose of this study was to identify off-ice variables that would correlate to on-ice skating sprint performance and cornering ability. Previous literature has not reported any off-ice testing variables that strongly correlate to on-ice cornering ability in ice hockey players. Thirty-six male hockey players aged 15-22 years (mean +/- SD: 16.3 +/- 1.7 years; weight = 70.8 +/- 10.4 kg; height = 175.6 +/- 4.1 cm) with an average of 10.3 +/- 3.0 years hockey playing experience (most at AA and AAA levels) participated in the study. The on-ice tests included a 35-m sprint and the cornering S test. The off-ice tests included the following: 30-m sprint, vertical jump, broad jump, 3 hop jump, Edgren side shuffle, Hexagon agility, side support, push-ups, and 15-second modified Wingate. The on-ice sprint test and cornering S test were strongly correlated (r = 0.70; p < 0.001). While many off-ice tests correlated with on-ice skating, measures of horizontal leg power (off-ice sprint and 3 hop jump) were the best predictors of on-ice skating performance, once weight and playing level were accounted for. These 4 variables accounted for a total of 78% (p < 0.0001) of the variance in on-ice sprint performance. No off-ice test accounted for unique variance in S-cornering performance beyond weight, playing level, and skating sprint performance. These data indicate that coaches should include horizontal power tests of off-ice sprint and 3 hop jump to adequately assess skating ability. To improve on-ice skating performance and cornering ability, coaches should also focus on the development of horizontal power through specific off-ice training, although future research will determine whether off-ice improvements in horizontal power directly transfer to improvements in on-ice skating.

  7. Ice Hockey Summit II: zero tolerance for head hits and fighting.

    PubMed

    Smith, Aynsley M; Stuart, Michael J; Dodick, David W; Roberts, William O; Alford, Patrick W; Ashare, Alan B; Aubrey, Mark; Benson, Brian W; Burke, Chip J; Dick, Randall; Eickhoff, Chad; Emery, Carolyn A; Flashman, Laura A; Gaz, Daniel V; Giza, Chris C; Greenwald, Richard M; Herring, Stanley A; Hoshizaki, T Blaine; Hudziak, James J; Huston, John; Krause, David; LaVoi, Nicole; Leaf, Matt; Leddy, John J; MacPherson, Alison; McKee, Ann C; Mihalik, Jason P; Moessner, Anne M; Montelpare, William J; Putukian, Margot; Schneider, Kathryn J; Szalkowski, Ron; Tabrum, Mark; Whitehead, James R; Wiese-Bjornstal, Diane M

    2015-01-01

    This study aimed to present currently known basic science and on-ice influences of sport-related concussion (SRC) in hockey, building upon the Ice Hockey Summit I action plan (2011) to reduce SRC. The prior summit proceedings included an action plan intended to reduce SRC. As such, the proceedings from Summit I served as a point of departure for the science and discussion held during Summit II (Mayo Clinic, Rochester, MN, October 2013). Summit II focused on (1) Basic Science of Concussions in Ice Hockey: Taking Science Forward, (2) Acute and Chronic Concussion Care: Making a Difference, (3) Preventing Concussions via Behavior, Rules, Education, and Measuring Effectiveness, (4) Updates in Equipment: Their Relationship to Industry Standards, and (5) Policies and Plans at State, National, and Federal Levels To Reduce SRC. Action strategies derived from the presentations and discussion described in these sectors were voted on subsequently for purposes of prioritization. The following proceedings include the knowledge and research shared by invited faculty, many of whom are health care providers and clinical investigators. The Summit II evidence-based action plan emphasizes the rapidly evolving scientific content of hockey SRC. It includes the most highly prioritized strategies voted on for implementation to decrease concussion. The highest-priority action items identified from the Summit include the following: (1) eliminate head hits from all levels of ice hockey, (2) change body checking policies, and (3) eliminate fighting in all amateur and professional hockey.

  8. Planets and Pucks.

    ERIC Educational Resources Information Center

    Brueningsen, Christopher; Krawiec, Wesley

    1993-01-01

    Presents a simple activity designed to allow students to experimentally verify Kepler's second law, sometimes called the law of equal areas. It states that areas swept out by a planet as it orbits the Sun are equal for equal time intervals. (PR)

  9. Neuropsychological factors related to college ice hockey concussions.

    PubMed

    Pedersen, Heather A; Ferraro, F Richard; Himle, Michael; Schultz, Caitlin; Poolman, Mark

    2014-05-01

    We analyzed data from 74 male collegiate hockey players. Each athlete's season began with a baseline administration of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) neuropsychology test battery. Fourteen athletes sustained a sport-related head injury and were readministered the test to assess the impact of the injury. A significant decrease in performance (compared to baseline) on immediate and delayed word recall and designs followed the first concussion. Following a second sport-related concussion, the 4 affected athletes showed significant decrease in visual motor speed. Performance improved on 2 response speed measures (Ps < .01). More errors occurred during a visual processing/discrimination task and immediate recall of designs declined (Ps < .05). We discuss the results in light of recent work related to the impact of early-life concussions and head injury on late-life consequences, such as chronic traumatic encephalopathy, and more immediate issues such as return-to-play decisions for athletes.

  10. Children's social relationships and motivation in sledge hockey.

    PubMed

    Wynnyk, Katrina; Spencer-Cavaliere, Nancy

    2013-10-01

    The purpose of this qualitative case study was to explore children with disabilities' social relationships and motivation to take part in sledge hockey. Harter's (1978) theory of Competence Motivation was used as the conceptual framework. Ten children (1 girl and 9 boys) between ages 11-16 years, who experienced a range of disabilities, participated. Primary data were collected using semistructured interviews, participant observations, and field and reflective notes. The thematic analysis led to four themes: (a) coach feedback, (b) parental involvement, (c) skill and belonging, and (d) (dis)ability sport. The findings revealed that interactions with significant others contributed extensively to the participant's perceptions of competence and motivation to participate, as did the sport's competitive nature. The findings are discussed in the context of Harter's theory and the children's sport and adapted physical activity inclusion literature.

  11. Explosive Model Tarantula V1/JWL++ Calibration of LX-17: #2

    SciTech Connect

    Souers, P C; Vitello, P

    2009-05-01

    Tarantula V1 is a kinetic package for reactive flow codes that seeks to describe initiation, failure, dead zones and detonation simultaneously. The most important parameter is P1, the pressure between the initiation and failure regions. Both dead zone formation and failure can be largely controlled with this knob. However, V1 does failure with low settings and dead zones with higher settings, so that it cannot fulfill its purpose in the current format. To this end, V2 is under test. The derivation of the initiation threshold P0 is discussed. The derivation of the initiation pressure-tau curve as an output of Tarantula shows that the initiation package is sound. A desensitization package is also considered.

  12. Proceedings from the Ice Hockey Summit on concussion: a call to action.

    PubMed

    Smith, A; Stuart, M; Greenwald, R; Benson, B; Dodick, D; Emery, C; Finnoff, J; Mihalik, J; Roberts, W; Sullivan, C A; Meeuwisse, W

    2011-07-01

    The objective of this proceedings is to integrate the concussion in sport literature and sport science research on safety in ice hockey to develop an action plan to reduce the risk, incidence, severity, and consequences of concussion in ice hockey. A rationale paper outlining a collaborative action plan to address concussions in hockey was posted for review two months prior to the Ice Hockey Summit: Action on Concussion. Focused presentations devoted specifically to concussion in ice hockey were presented during the Summit and breakout sessions were used to develop strategies to reduce concussion in the sport. This proceedings and a detailed scientific review (a matrix of solutions) were written to disseminate the evidence-based information and resulting concussion reduction strategies. The manuscripts were reviewed by the authors, advisors and contributors to ensure that the opinions and recommendations reflect the current level of knowledge on concussion in hockey. Six components of a potential solution were articulated in the Rationale paper and became the topics for breakout groups that followed the professional, scientific lectures. Topics that formed the core of the action plan were: metrics and databases; recognizing, managing and return to play; hockey equipment and ice arenas; prevention and education; rules and regulations; and expedient communication of the outcomes. The attendees in breakout sessions identified action items for each section. The most highly ranked action items were brought to a vote in the open assembly, using an Audience Response System (ARS). The strategic planning process was conducted to assess: Where are we at?; Where must we get to?; and What strategies are necessary to make progress on the prioritized action items? Three prioritized action items for each component of the solution and the percentage of the votes received are listed in the body of this proceedings.

  13. Efficacy of a Four-Week Uphill Sprint Training Intervention in Field Hockey Players.

    PubMed

    Jakeman, John R; McMullan, Judith; Babraj, John A

    2016-10-01

    Jakeman, JR, McMullan, J, and Babraj, JA. Efficacy of a four-week uphill sprint training intervention in field hockey players. J Strength Cond Res 30(10): 2761-2766, 2016-Current evidence increasingly suggests that very short, supramaximal bouts of exercise can have significant health and performance benefits. Most research conducted in the area, however, uses laboratory-based protocols, which can lack ecological validity. The purpose of this study was to examine the effects of a high-intensity sprint training program on hockey-related performance measures. Fourteen semiprofessional hockey players either completed a 4-week high-intensity training (HIT) intervention, consisting of a total of 6 sessions of HIT, which progressively increased in volume (n = 7), or followed their normal training program (Con; n = 7). Straight-line sprint speed, with and without a hockey stick and ball, and slalom sprint speed, with and without a hockey stick and ball, were used as performance indicators. Maximal sprint speed over 22.9 m was also assessed. On completion of the 4-week intervention, straight-line sprint speed improved significantly in the HIT group (∼3%), with no changes in performance for the Con group. Slalom sprint speed, both with and without a hockey ball, was not significantly different after the training program in either group. Maximal sprint speed improved significantly (12.1%) in the HIT group, but there was no significant performance change in the Con group. The findings of this study indicate that a short period of HIT can significantly improve hockey-related performance measures and could be beneficial to athletes and coaches in field settings.

  14. Physiological, physical and on-ice performance criteria for selection of elite ice hockey teams

    PubMed Central

    Roczniok, R; Stanula, A; Mostowik, A; Kowalczyk, M; Fidos-Czuba, O; Zając, A

    2015-01-01

    The purpose of this study was to examine physiological and physical determinants of ice-hockey performance in order to assess their impact on the result during a selection for ice hockey. A total of 42 ice hockey players took part in the selection camp. At the end of the camp 20 best players were selected by team of expert coaches to the ice hockey team and created group G1, while the second group (G2) consisted of not selected players (non-successful group Evaluation of goodness of fit of the model to the data was based on the Hosmer Lemeshow test. Ice hockey players selected to the team were taller 181.95±4.02 cm, had lower% body fat 13.17±3.17%, a shorter time to peak power 2.47±0.35 s, higher relative peak power 21.34±2.41 W·kg−1 and higher relative total work 305.18±28.41 J·kg−1. The results of the aerobic capacity test showed significant differences only in case of two variables. Ice hockey players in the G1 had higher VO2max 4.07±0.31 l·min−1 values than players in the G2 as well as ice hockey players in G1 showed a higher level of relative VO2max 51.75±2.99 ml·min−1·kg−1 than athletes in G2. Ice hockey players selected to the team (G1) performed better in the 30 m Forwards Sprint 4.28±0.31 s; 6x9 Turns 12.19±0.75 s; 6x9 stops 12.79±0.49 s and Endurance test (6x30 m stops) 32.01±0.80 s than players in G2. The logistic regression model showed that the best predictors of success in the recruitment process of top level ice hockey players were time to peak power, relative peak power, VO2max and 30 m sprint forwards on ice. On the basis of the constructed predictive logistic regression model it will be possible to determine the probability of success of the athletes during following the selection processes to the team. PMID:26985133

  15. Conservative management of an elite ice hockey goaltender with femoroacetabular impingement (FAI): a case report

    PubMed Central

    MacIntyre, Kyle; Gomes, Brendan; MacKenzie, Steven; D’Angelo, Kevin

    2015-01-01

    Objective: To detail the presentation of an elite male ice hockey goaltender with cam-type femoroacetabular impingement (FAI) and acetabular labral tears. This case will outline the prevalence, clinical presentation, imaging criteria, pathomechanics, and management of FAI, with specific emphasis on the ice hockey goaltender. Clinical Features: A 22-year old retired ice hockey goaltender presented to a chiropractor after being diagnosed by an orthopaedic surgeon with MRI confirmed left longitudinal and chondral flap acetabular labral tears and cam-type femoroacetabular impingement (FAI). As the patient was not a candidate for surgical intervention, a multimodal conservative treatment approach including manual therapy, electroacupuncture and rehabilitation exercises were implemented. Summary: FAI is prevalent in ice hockey players, particularly with goaltenders. Both skating and position-dependent hip joint mechanics involved in ice hockey may exacerbate or contribute to acquired and congenital forms of symptomatic FAI. As such, practitioners managing this population must address sport-specific demands in manual therapy, rehabilitation and physical training, to improve functional outcomes and prevent future injury. PMID:26816416

  16. Integration of the functional movement screen into the National Hockey League Combine.

    PubMed

    Rowan, Chip P; Kuropkat, Christiane; Gumieniak, Robert J; Gledhill, Norman; Jamnik, Veronica K

    2015-05-01

    The sport of ice hockey requires coordination of complex skills involving musculoskeletal and physiological abilities while simultaneously exposing players to a high risk for injury. The Functional Movement Screen (FMS) was developed to assess fundamental movement patterns that underlie both sport performance and injury risk. The top 111 elite junior hockey players from around the world took part in the 2013 National Hockey League Entry Draft Combine (NHL Combine). The FMS was integrated into the comprehensive medical and physiological fitness evaluations at the request of strength and conditioning coaches with affiliations to NHL teams. The inclusion of the FMS aimed to help develop strategies that could maximize its utility among elite hockey players and to encourage or inform further research in this field. This study evaluated the outcomes of integrating the FMS into the NHL Combine and identified any links to other medical plus physical and physiological fitness assessment outcomes. These potential associations may provide valuable information to identify elements of future training programs that are individualized to athletes' specific needs. The results of the FMS (total score and number of asymmetries identified) were significantly correlated to various body composition measures, aerobic and anaerobic fitness, leg power, timing of recent workouts, and the presence of lingering injury at the time of the NHL Combine. Although statistically significant correlations were observed, the implications of the FMS assessment outcomes remain difficult to quantify until ongoing assessment of FMS patterns, tracking of injuries, and hockey performance are available.

  17. Many roads lead to Rome--developmental paths to Olympic gold in men's field hockey.

    PubMed

    Güllich, Arne

    2014-01-01

    This study examined the developmental sporting activities of the Olympic Champions 2012 in men's field hockey. The volume of organised practice/training and non-organised sporting leisure play in both field hockey and other sports through childhood, adolescence and adulthood was examined and compared between the Olympic Champions and (1) current national class players and (2) international medallists of one decade earlier. Analyses revealed that the Olympic Champions performed moderate volumes of organised field hockey practice/training throughout their career and attained their first international senior medal after accumulating 4393 ± 1389 practice/training hours, but they engaged in extensive other sporting activities during childhood and youth. It took them 18 ± 3 years of involvement to attain an international medal and they had engaged for 22 ± 3 years when winning the Olympic gold medal. The Olympic Champions did not differ from national class players in the amount of hockey-specific practice/training, but in greater amounts of organised involvement in other sports and later specialisation. They differed from the international medallists of one decade earlier in less increase of organised hockey-specific practice/training during adulthood and a longer period of involvement until attaining their first international medal. The sporting activities were characterised by sizeable interindividual variation within each subsample. The findings are reflected against the deliberate practice and Developmental Model of Sports Participation (DMSP) frameworks and are discussed with reference to the concept of long-term sustainability.

  18. Comparison of body composition and nutrients' deficiencies between Portuguese rink-hockey players.

    PubMed

    Silva, Maria-Raquel G; Silva, Hugo-Henrique

    2017-01-01

    We evaluated dietary intake and body composition of child and adolescent rink-hockey players and controls. Seventy-two male rink-hockey players (38 children and 34 adolescents) and 79 male controls (43 children and 36 adolescents) were evaluated in order to collect training data, detailed dietary intake and body composition. Rink-hockey players presented significantly lower body fat (BF) and higher fat-free mass (FFM) than controls. Mean intakes of carbohydrate and protein were considered to be adequate, but mean intakes of fat were above the recommended levels in athletes. Significant differences were found for energy intake (EI) and exercise energy expenditure (EEE) between athletes and controls (P < 0.05), resulting in some cases of low energy availability in rink-hockey players. Significant group differences (P < 0.05) were also observed for vitamins and mineral intakes in child and adolescent rink-hockey players due to higher mean intakes in control groups. Low intakes of vitamins D, E and K, calcium, iron, boron and magnesium were reported in athletes, with exception for thiamine (P = 0.449), riboflavin (P = 0.246), pantothenic acid (P = 0.065), magnesium (P = 0.061) and phosphorus (P = 0.051) in children and for niacin (P = 0.652), vitamin D (P = 0.406) and zinc (P = 0.783) in adolescents.

  19. Do physical maturity and birth date predict talent in male youth ice hockey players?

    PubMed

    Sherar, Lauren B; Baxter-Jones, Adam D G; Faulkner, Robert A; Russell, Keith W

    2007-06-01

    The aim of this study was to examine the relationships among biological maturity, physical size, relative age (i.e. birth date), and selection into a male Canadian provincial age-banded ice hockey team. In 2003, 619 male ice hockey players aged 14-15 years attended Saskatchewan provincial team selection camps, 281 of whom participated in the present study. Data from 93 age-matched controls were obtained from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-1997). During the initial selection camps, birth dates, heights, sitting heights, and body masses were recorded. Age at peak height velocity, an indicator of biological maturity, was determined in the controls and predicted in the ice hockey players. Data were analysed using one-way analysis of variance, logistic regression, and a Kolmogorov-Smirnov test. The ice hockey players selected for the final team were taller, heavier, and more mature (P < 0.05) than both the unselected players and the age-matched controls. Furthermore, age at peak height velocity predicted (P < 0.05) being selected at the first and second selection camps. The birth dates of those players selected for the team were positively skewed, with the majority of those selected being born in the months January to June. In conclusion, team selectors appear to preferentially select early maturing male ice hockey players who have birth dates early in the selection year.

  20. Evaluation of anthropometric, physiological, and skill-related tests for talent identification in female field hockey.

    PubMed

    Keogh, Justin W L; Weber, Clare L; Dalton, Carl T

    2003-06-01

    The purpose of the present study was to develop an effective testing battery for female field hockey by using anthropometric, physiological, and skill-related tests to distinguish between regional representative (Rep, n = 35) and local club level (Club, n = 39) female field hockey players. Rep players were significantly leaner and recorded faster times for the 10-m and 40-m sprints as well as the Illinois Agility Run (with and without dribbling a hockey ball). Rep players also had greater aerobic and lower body muscular power and were more accurate in the shooting accuracy test, p < 0.05. No significant differences between groups were evident for height, body mass, speed decrement in 6 x 40-m repeated sprints, handgrip strength, or pushing speed. These results indicate that %BF, sprinting speed, agility, dribbling control, aerobic and muscular power, and shooting accuracy can distinguish between female field hockey players of varying standards. Therefore talent identification programs for female field hockey should include assessments of these physical parameters.

  1. Psychosocial Outcomes of Sport Concussions in Youth Hockey Players.

    PubMed

    Mrazik, Martin; Brooks, Brian L; Jubinville, Andrea; Meeuwisse, Willem H; Emery, Carolyn A

    2016-06-01

    The objective is to evaluate the psychological outcomes arising from sport concussions. Participants included AA and AAA level Bantam and Midget hockey players (n = 672) between 12 and 17 years of age (mean = 15.0 years; SD = 1.2) enrolled in a large cohort study. All participants completed baseline tests including the Behavior Assessment System for Children, 2nd Edition (BASC2) and a pre-season medical questionnaire (PSQ) completed by parents that included a retrospective report of prior concussions and injuries. Players were assigned to 4 groups: no injury (NONE), concussion (CO) and musculoskeletal (MSK) injuries or both (COMB). Participants in the CO and COMB groups demonstrated significantly higher rates of psychological difficulties compared with other groups [F(63, 1800) = 1.43, p = .016, partial η(2) = 0.05) and on select clinical scales measuring atypicality, locus of control, anxiety, depression, sense of inadequacy, somatization, and attention. In addition, results from the composite clinical scales reached statistical significance for internalizing problems and emotional symptom index. Effect sizes were minimal with the exception of comparisons between the NONE and COMB groups where effect sizes were medium to large. Proportions above clinical cut-off scores set by the BASC2 were higher for the COMB group compared with CO, MSK, or NONE groups. Results suggest smaller percentage of youth may be more prone to psychological sequelae following concussion.

  2. Testosterone, cortisol and anxiety in elite field hockey players.

    PubMed

    Aguilar, Raúl; Jiménez, Manuel; Alvero-Cruz, José R

    2013-07-02

    The aim of the present study was to assess the change in the levels of testosterone and cortisol after victory and defeat in male field hockey players during an important tournament. In the beginning of the game series, the players were ranked very closely to achieve (for the first time) the championship rising to The Honor Division-A, the highest status national category. The first game resulted in a 7-4 victory, the second game resulted in a 6-1 victory, and the third game resulted in a 1-2 defeat. As expected, there were changes in testosterone levels after the competition, dropping in the game which ended in defeat, and rising slightly in the two games which ended in victory; there were also changes in cortisol levels, rising in the game which ended in defeat, and showing no variations in the games which ended in victory; correlational analyses congruently showed that defeat led to rises in cortisol whereas victory led to rises in testosterone; anticipatory somatic anxiety was related to cortisol levels prior to games, and physical exertion during competition was related to the change in testosterone levels (suggesting an inhibitory effect) but not to the change in cortisol levels. Hence, this pattern of hormonal responses to a real-life dominance challenge complied with Mazur's (1985) [16] biosocial model of status and dominance motivation, by showing that testosterone and cortisol are linked to victory and defeat in a theoretically predictable fashion.

  3. Rhinitis in Elite and Non-Elite Field Hockey Players.

    PubMed

    Walker, A; Surda, P; Rossiter, M; Little, S

    2017-01-01

    Rhinitis has been demonstrated to impose a significant disease burden upon the general population. We sought to determine the prevalence of rhinitis in athletes; to investigate its relationship with co-existing allergic symptoms; and to quantify the impact of rhinitis on quality of life in the athlete.3 subgroups were studied: elite field hockey players (FHP); non-elite FHP; and a sedentary control group.Participants were asked to complete a rhinitis self-report questionnaire; the "Allergic Questionnaire for Athletes" (AQUA), and quality of life Sinonasal Outcome Test - 22 (SNOT-22).142 participants completed the study (52 elite FHP; 40 non-elite FHP; 50 controls). There was a significantly higher prevalence of rhinitis in the elite and non-elite FHP groups than the sedentary control group (52% and 43% vs. 22%, p<0.05). Mean AQUA score was significantly higher in athletes with rhinitis. Quality of life scores were significantly worse in athletes with rhinitis than those without rhinitis (p<0.05).This study suggests regular exercise is associated with a significant increase in the prevalence of rhinitis. Elite FHP were most likely to report rhinitis, but the least likely to be using regular treatment. Quality of life was negatively affected, confirming the importance of nasal health to athlete welfare.

  4. Predictors of Speed Using Off-Ice Measures of College Hockey Players.

    PubMed

    Runner, Aaron R; Lehnhard, Robert A; Butterfield, Stephen A; Tu, Shihfen; OʼNeill, Terrence

    2016-06-01

    The purpose of this study was to examine the relationship between commonly employed dry-land performance tests and skating speed in male collegiate ice hockey players. Forty male National Collegiate Athletic Association Division I hockey players were tested on the following performance variables: vertical jump (VJ), standing broad jump, 40-yard dash, and maximal back squat (SQT). The subjects also performed 3 skating tests: the 90-ft forward acceleration test, the 90-ft backward acceleration test, and the 50-ft flying top speed test (F50). Pearson correlation coefficients were applied to compare the strength of association between each selected off-ice measure and each on-ice measure. Three multiple regression equations were then used to compare the weighted strengths of association between predictor and criterion variables. Only VJ showed significance in relation to skating speed (p = 0.011). These results suggest that meaningful performance testing in ice hockey players should occur mainly on the ice.

  5. A physical profile of elite female ice hockey players from the USA.

    PubMed

    Ransdell, Lynda B; Murray, Teena

    2011-09-01

    Despite impressive numbers of hockey participants, there is little research examining elite female ice hockey players. Therefore, the purpose of this study was to describe the physical characteristics of elite female ice hockey players who were trying out for the 2010 US Women's Ice Hockey team. Twenty-three women participated in the study and were evaluated for body mass (kilograms), height (centimeters), age (years) vertical jump (centimeters), standing long jump (centimeters), 1RM front squat (kilograms), front squat relative to body mass (percent), 1RM bench press (kilograms), bench press relative to body mass (percent), pull-ups, and body composition (percent body fat). The athletes in this sample were 24.7 years of age (SD = 3.1) and 169.7 cm tall (SD = 6.9); on average, they weighed 70.4 kg (SD = 7.1) and reported 15.8% body fat (SD = 1.9). Mean vertical jump height was 50.3 cm (SD = 5.7) and standing long jump was 214.8 cm (SD = 10.9). Mean 1RM for the upper body strength (bench press) was 65.3 kg (SD = 12.2) (95.1 ± 15.5% of body mass), and 1RM for lower body (front squat) was 88.6 kg (SD = 11.2) (127.7 ± 16.3% of body mass). This study is the first to report the physical characteristics of elite female ice hockey players from the USA. Data should assist strength and conditioning coaches in identifying talent, testing for strengths and weaknesses, comparing future teams to these indicators, and designing programs that will enhance the performance capabilities of female ice hockey athletes.

  6. Lesbian erotics at women's hockey: fans, flashing, and the Booby Orrs.

    PubMed

    Davidson, Judy

    2009-01-01

    This article analyzes a public breast flashing event that occurred during the women's ice hockey tournament at the OutGames/Western Cup Lesbigay athletic event in 2007. Employing a postfoundational perspective, I first contextualize the ice hockey subculture of the team called the Booby Orrs, outlining some of our history, norms, and context. I then tell the particular story that leads to our fans flashing their breasts as we finally scored some goals. I end with my analysis of this event: how a public nude display of sexualized women's breasts in a lesbian-coded public space prompted a resistant sporting moment, at least contingently.

  7. Layer thinning transition in an achiral four-ring hockey stick shaped liquid crystal

    NASA Astrophysics Data System (ADS)

    Paul, Manoj Kr.; Nath, Rahul K.; Moths, Brian; Pan, LiDong; Wang, Shun; Deb, Rajdeep; Shen, Yongqiang; Rao, Nandiraju V. S.; Huang, C. C.

    2012-12-01

    Depolarized reflected light microscopy and high resolution optical reflectivity measurements have been conducted on free-standing films of an achiral four-ring hockey stick shaped liquid crystal exhibiting SmA-B2-SmX* transition sequence. A layer thinning transition above the bulk isotropic-SmA phase transition has been observed. This behaviour was highly irreproducible, indicating an irregular layer thinning transition. From optical reflectivity data, both thickness of the free-standing films and the smectic interlayer spacing were determined. This is the first report of the layer thinning transition in a hockey stick shaped liquid crystal.

  8. The past, present, and future of hockey-stick-shaped liquid crystals

    NASA Astrophysics Data System (ADS)

    Choi, E.-Joon

    2014-02-01

    Recently, the liquid crystalline materials with a bent-core mesogen have attracted attentions because their interesting properties such as polarity and biaxiality of the mesophase. There are several types of bent-core mesogenic structures have been reported, for instance, banana-shaped, V-shaped molecules, boomerang-shaped, hockey stick-shaped, and Yshaped molecules. In this study, the liquid crystals and the reactive mesogens with the hockey-stick shaped mesogens will be described concerning with the structure-property relationship.

  9. Ice Hockey Players Using a Weighted Implement when Training on the Ice: A Randomized Control Trial

    ERIC Educational Resources Information Center

    Stark, Timothy W.; Tvoric, Bojan; Walker, Bruce; Noonan, Dom; Sibla, Janeene

    2009-01-01

    The purpose of this study was to investigate the potential for improving hockey players' performance using a weighted implement on the ice. Forty-eight players were tested using a grip strength dynamometer. They also were assessed on their abilities to stick-handle. The participants were randomly placed into a control or research group. The…

  10. An Examination of the Relative Age Effect in Developmental Girls' Hockey in Ontario

    ERIC Educational Resources Information Center

    Smith, Kristy L.; Weir, Patricia L.

    2013-01-01

    The relative age effect (RAE) suggests that athletes may be provided with greater opportunities for success depending on the position of their birthdate in a sport's selection year. While the effect has been well established in men's sports, less is known about women's sports. This study examined the RAE in developmental girls' hockey in Ontario.…

  11. Describing Strategies Used by Elite, Intermediate, and Novice Ice Hockey Referees

    ERIC Educational Resources Information Center

    Hancock, David J.; Ste-Marie, Diane M.

    2014-01-01

    Much is known about sport officials' decisions (e.g., anticipation, visual search, and prior experience). Comprehension of the entire decision process, however, requires an ecologically valid examination. To address this, we implemented a 2-part study using an expertise paradigm with ice hockey referees. Purpose: Study 1 explored the…

  12. Receiving Video-Based Feedback in Elite Ice-Hockey: A Player's Perspective

    ERIC Educational Resources Information Center

    Nelson, Lee J.; Potrac, Paul; Groom, Ryan

    2014-01-01

    The aim of this paper was to provide some rich insights into how an elite ice-hockey player responded to his coaches' pedagogical delivery of video-based feedback sessions. Data for this study were gathered through a series of in-depth, semi-structured interviews and a reflective log relating to those interviews. The interviews were transcribed…

  13. Experiential Learning in the Introductory Class: The Role of Minor League Hockey in Teaching Social Psychology

    ERIC Educational Resources Information Center

    Forrest, Krista D.

    2005-01-01

    To convince my students they are surrounded by social psychology, we attended a minor league hockey game. During the next class period I asked students to write a brief paragraph about their experiences. From those paragraphs I chose four reoccurring themes to analyze from a social psychological perspective. My introductory classes and I benefited…

  14. Checking in: An Analysis of the (Lack of) Body Checking in Women's Ice Hockey

    ERIC Educational Resources Information Center

    Weaving, Charlene; Roberts, Samuel

    2012-01-01

    Despite the growing popularity of women's ice hockey in North America, players continue to face limitations because of the prohibition of body checking. In this paper, we argue from a liberal feminist philosophical perspective that this prohibition reinforces existing traditional stereotypes of female athletes. Because the women's game does not…

  15. Table Hockey: Attack or Linking? Psychoanalytic Psychotherapy with an Autistic Boy

    ERIC Educational Resources Information Center

    Nilsson, May

    2009-01-01

    This paper explores some issues that might arise when one considers having a table hockey game in the therapy room, and describes how an autistic boy, aged four-and-a-half when starting treatment, used that game. The unfolding process from withdrawal to separateness, intersubjectivity and playfulness is illustrated by the progress of two years of…

  16. Trajectories of Affective States in Adolescent Hockey Players: Turning Point and Motivational Antecedents

    ERIC Educational Resources Information Center

    Gaudreau, Patrick; Amiot, Catherine E.; Vallerand, Robert J.

    2009-01-01

    This study examined longitudinal trajectories of positive and negative affective states with a sample of 265 adolescent elite hockey players followed across 3 measurement points during the 1st 11 weeks of a season. Latent class growth modeling, incorporating a time-varying covariate and a series of predictors assessed at the onset of the season,…

  17. The Control of Externalities in Sports Leagues: An Analysis of Restrictions in the National Hockey League

    ERIC Educational Resources Information Center

    Carlton, Dennis W.; Frankel, Alan S.; Landes, Elisabeth M.

    2004-01-01

    This paper provides one of the few successful demonstrations of the efficiency of certain types of restrictions in the context of a joint venture. The joint venture we examine is the National Hockey League (NHL) in the 1980s, which was then composed of 21 separately owned teams. (It now has 30 teams.) The restriction we analyze is the NHL rule on…

  18. Validation of the FAST skating protocol to predict aerobic power in ice hockey players.

    PubMed

    Petrella, Nicholas J; Montelpare, William J; Nystrom, Murray; Plyley, Michael; Faught, Brent E

    2007-08-01

    Few studies have reported a sport-specific protocol to measure the aerobic power of ice hockey players using a predictive process. The purpose of our study was to validate an ice hockey aerobic field test on players of varying ages, abilities, and levels. The Faught Aerobic Skating Test (FAST) uses an on-ice continuous skating protocol on a course measuring 160 feet (48.8 m) using a CD to pace the skater with a beep signal to cross the starting line at each end of the course. The FAST incorporates the principle of increasing workload at measured time intervals during a continuous skating exercise. Step-wise multiple regression modelling was used to determine the estimate of aerobic power. Participants completed a maximal aerobic power test using a modified Bruce incremental treadmill protocol, as well as the on-ice FAST. Normative data were collected on 406 ice hockey players (291 males, 115 females) ranging in age from 9 to 25 y. A regression to predict maximum aerobic power was developed using body mass (kg), height (m), age (y), and maximum completed lengths of the FAST as the significant predictors of skating aerobic power (adjusted R2 = 0.387, SEE = 7.25 mL.kg-1.min-1, p < 0.0001). These results support the application of the FAST in estimating aerobic power among male and female competitive ice hockey players between the ages of 9 and 25 years.

  19. Prediction of ice skating performance with off-ice testing in women's ice hockey players.

    PubMed

    Bracko, M R; George, J D

    2001-02-01

    Off-ice predictors of skating performance have not been investigated for women's hockey players. The purpose of this study was to identify the off-ice variables associated with high-performance skating acceleration, speed, agility, and on-ice anaerobic capacity and power in women's ice hockey players. Sixty-one women's ice hockey players between the ages of 8 and 16 years (x age = 12.18 +/- 2.05 years, x playing experience = 4.68 +/- 2.69 years) participated in the study. Subjects were 1-4 months postseason. Some players were continuing to play once per week during the off-season. Skating tests (ST) included (a) 6.10-m acceleration, (b) 47.85-m speed, (c) agility cornering S turn, and (d) modified repeat skate test (MRS). Two trials of each ST were measured with a photoelectric timing system (except MRS, which was measured with 1 trial). The off-ice variables that were evaluated included age, years of playing experience, height, body mass, predicted fat percentage, sit-and-reach flexibility, vertical jump height, 40-yd dash time, and 1-minute timed sit-ups and push-ups. The results of this study show that 40-yd dash time is the strongest predictor of skating speed in women's hockey players ages 8-16 years old. From the regression procedure the best prediction equation was speed = 4.913 - (0.0107 x kilograms) + (0.4356 x 40-yd dash time).

  20. A test of motor skill-specific action embodiment in ice-hockey players.

    PubMed

    Ong, Nicole T; Lohse, Keith R; Chua, Romeo; Sinnett, Scott; Hodges, Nicola J

    2014-07-01

    To further our understanding of the role of the motor system in comprehending action-related sentences, we compared action experts (athletes) to visual experts (fans) and novices when responding with an action-specific effector (either hand or foot). These conditions allowed inferences about the degree and specificity of embodiment in language comprehension. Ice hockey players, fans and novices made speeded judgments regarding the congruence between an auditorily presented sentence and a subsequently presented picture. Picture stimuli consisted of either hockey or everyday items. Half of these pictures 'matched' the action implied in the preceding sentence. Further, the action in these images involved either primarily the hand or the foot. For everyday items, action-matched items were responded to faster than action-mismatched items. However, only the players and fans showed the action-match effect for hockey items. There were no consistent effector-stimuli compatibility effects, nor skill-based interactions with compatibility, suggesting that the action-match effect was not based on motor ability per se, but rather a construction of the action based on knowledge or visual experience with the hockey related sentences.

  1. Shoulder Range of Motion and Strength in Professional Ice Hockey Players.

    PubMed

    Cohn, Randy M; Strauss, Eric J; Jazrawi, Laith M; Feldman, Andrew J

    2015-03-01

    Ice hockey is a fast paced sport with unique injury potential. There are no studies in the literature that examine the shoulder strength and range of motion in this population. Players on a single professional ice hockey team underwent a comprehensive examination of shoulder motion and strength. Shoulder motion and strength between right and left extremities were compared within athletes. Comparisons were made between right and left handed players, players that shoot right versus left handed, and by position. Within individual athletes, there was no difference in motion or strength between right and left shoulders. There was no difference in motion or strength between the dominant and non-dominant shoulder and players that shoot right versus left handed. Defensemen had a statistically significant increase in external rotation with the arm at the side for the left shoulder (66° versus 55°, p = 0.02) and a trend towards increased external rotation with the arm at the side for the right shoulder (65° versus 56°, p = 0.07). In professional ice hockey players, there is no difference in shoulder motion and strength between the right and left upper extremity. Ice hockey defensemen may have more external rotation with the arm at the side than forward.

  2. Combined Plyometric & Strength Training Improves Ice-hockey Players` On-ice Sprint.

    PubMed

    Dæhlin, Torstein E; Haugen, Ole C; Haugerud, Simen; Hollan, Ivana; Raastad, Truls; Rønnestad, Bent R

    2016-12-05

    Combined plyometric and strength training have previously been suggested as a strategy to improve skating performance in ice hockey players. However, the effects of combined plyometric and strength training has not been previously been compared to the effects of strength training only.

  3. Bone properties in child and adolescent male hockey and soccer players.

    PubMed

    Falk, Bareket; Braid, Sarah; Moore, Michael; Yao, Matthew; Sullivan, Phil; Klentrou, Nota

    2010-07-01

    Children and adolescents who train extensively in high-impact, weight-bearing activities have enhanced bone mineral density. The purpose of this study was to evaluate bone strength, as reflected by quantitative ultrasound (QUS, Sunlight Omniscence), of child (10-12 yrs old) and adolescent (14-16 yrs old) male soccer and hockey players in comparison with age-matched controls. The groups included 30 child (CH) and 31 adolescent (AH) hockey players, 26 child (CS) and 30 adolescent (AS) soccer players, as well as 34 child (CC) and 31 adolescent (AC) healthy, non-athletic, age-matched controls. All athletes trained at an elite level year-round, with no difference in training volume between groups. Ultrasound speed of sound (SOS) was measured at the distal-radius and mid-tibia. In both age groups, hockey players were the heaviest and had the highest fat-free mass. No differences were found among groups in total energy intake, calcium or vitamin D intake. Radial and tibial SOS increased with age. Hockey players had higher radial SOS in both age groups (children: CH:3763+/-74, CS:3736+/-77, CC:3721+/-88 m/s; adolescents: AH:3809+/-105, AS:3767+/-85, AC:3760+/-94 m/s). Tibial SOS was higher in soccer players compared with controls. In spite of the higher body mass and fat-free mass in hockey players, their tibial SOS was similar to the non-athletes in both age groups. These findings support previous suggestions of sport-specific effects on bone strength. However, they need to be corroborated with longitudinal or prospective intervention studies.

  4. Caffeinated Energy Drinks Improve High-Speed Running in Elite Field Hockey Players.

    PubMed

    Del Coso, Juan; Portillo, Javier; Salinero, Juan José; Lara, Beatriz; Abian-Vicen, Javier; Areces, Francisco

    2016-02-01

    The aim of this investigation was to determine the efficacy of a caffeine-containing energy drink to improve physical performance of elite field hockey players during a game. On 2 days separated by a week, 13 elite field hockey players (age and body mass = 23.2 ± 3.9 years and 76.1 ± 6.1 kg) ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo drink). After 60 min for caffeine absorption, participants played a simulated field hockey game (2 × 25 min). Individual running pace and instantaneous speed during the game were assessed using GPS devices. The total number of accelerations and decelerations was determined by accelerometry. Compared with the placebo drink, the caffeinated energy drink did not modify the total distance covered during the game (6,035 ± 451 m and 6,055 ± 499 m, respectively; p = .87), average heart rate (155 ± 13 beats per min and 158 ± 18 beats per min, respectively; p = .46), or the number of accelerations and decelerations (697 ± 285 and 618 ± 221, respectively; p = .15). However, the caffeinated energy drink reduced the distance covered at moderate-intensity running (793 ± 135 and 712 ± 116, respectively; p = .03) and increased the distance covered at high-intensity running (303 ± 67 m and 358 ± 117 m; p = .05) and sprinting (85 ± 41 m and 117 ± 55 m, respectively; p = .02). Elite field hockey players can benefit from ingesting caffeinated energy drinks because they increase the running distance covered at high-intensity running and sprinting. Increased running distance at high speed might represent a meaningful advantage for field hockey performance.

  5. Off-Ice Anaerobic Power Does Not Predict On-Ice Repeated Shift Performance in Hockey.

    PubMed

    Peterson, Ben J; Fitzgerald, John S; Dietz, Calvin C; Ziegler, Kevin S; Baker, Sarah E; Snyder, Eric M

    2016-09-01

    Peterson, BJ, Fitzgerald, JS, Dietz, CC, Ziegler, KS, Baker, SE, and Snyder, EM. Off-ice anaerobic power does not predict on-ice repeated shift performance in hockey. J Strength Cond Res 30(9): 2375-2381, 2016-Anaerobic power is a significant predictor of acceleration and top speed in team sport athletes. Historically, these findings have been applied to ice hockey although recent research has brought their validity for this sport into question. As ice hockey emphasizes the ability to repeatedly produce power, single bout anaerobic power tests should be examined to determine their ability to predict on-ice performance. We tested whether conventional off-ice anaerobic power tests could predict on-ice acceleration, top speed, and repeated shift performance. Forty-five hockey players, aged 18-24 years, completed anthropometric, off-ice, and on-ice tests. Anthropometric and off-ice testing included height, weight, body composition, vertical jump, and Wingate tests. On-ice testing consisted of acceleration, top speed, and repeated shift fatigue tests. Vertical jump (VJ) (r = -0.42; r = -0.58), Wingate relative peak power (WRPP) (r = -0.32; r = -0.43), and relative mean power (WRMP) (r = -0.34; r = -0.48) were significantly correlated (p ≤ 0.05) to on-ice acceleration and top speed, respectively. Conversely, none of the off-ice tests correlated with on-ice repeated shift performance, as measured by first gate, second gate, or total course fatigue; VJ (r = 0.06; r = 0.13; r = 0.09), WRPP (r = 0.06; r = 0.14; r = 0.10), or WRMP (r = -0.10; r = -0.01; r = -0.01). Although conventional off-ice anaerobic power tests predict single bout on-ice acceleration and top speed, they neither predict the repeated shift ability of the player, nor are good markers for performance in ice hockey.

  6. Knee joint position sense of roller hockey players: a comparative study.

    PubMed

    Venâncio, João; Lopes, Diogo; Lourenço, Joaquim; Ribeiro, Fernando

    2016-06-01

    This study aimed to compare knee joint position sense of roller hockey players with an age-matched group of non-athletes. Forty-three male participants voluntarily participated in this cross-sectional study: 21 roller hockey players (mean age: 23.2 ± 4.2 years old, mean weight: 81.8 ± 9.8 kg, mean height: 180.5 ± 4.1 cm) and 22 age-matched non-athletes (mean age: 23.7 ± 3.9 years old, mean weight: 85.0 ± 6.2 kg, mean height: 181.5 ± 5.0 cm). Knee joint position sense of the dominant limb was evaluated using a technique of open-kinetic chain and active knee positioning. Joint position sense was reported using absolute, relative and variable angular errors. The main results indicated that the group of roller hockey players showed significantly lower absolute (2.4 ± 1.2º vs. 6.5 ± 3.2º, p ≤ 0.001) and relative (1.7 ± 2.1º vs. 5.8 ± 4.4º, p ≤ 0.001) angular errors in comparison with the non-athletes group. In conclusion, the results from this present study suggest that proprioceptive acuity, assessed by measuring joint position sense, is increased in roller hockey players. The enhanced proprioception of the roller hockey players could contribute to injury prevention and improved performance during sporting activities.

  7. Aggression, Violence and Injury in Minor League Ice Hockey: Avenues for Prevention of Injury

    PubMed Central

    Cusimano, Michael D.; Ilie, Gabriela; Mullen, Sarah J.; Pauley, Christopher R.; Stulberg, Jennifer R.; Topolovec-Vranic, Jane; Zhang, Stanley

    2016-01-01

    Background In North America, more than 800,000 youth are registered in organized ice hockey leagues. Despite the many benefits of involvement, young players are at significant risk for injury. Body-checking and aggressive play are associated with high frequency of game-related injury including concussion. We conducted a qualitative study to understand why youth ice hockey players engage in aggressive, injury-prone behaviours on the ice. Methods Semi-structured interviews were conducted with 61 minor ice hockey participants, including male and female players, parents, coaches, trainers, managers and a game official. Players were aged 13–15 playing on competitive body checking teams or on non-body checking teams. Interviews were manually transcribed, coded and analyzed for themes relating to aggressive play in minor ice hockey. Results Parents, coaches, teammates and the media exert a large influence on player behavior. Aggressive behavior is often reinforced by the player’s social environment and justified by players to demonstrate loyalty to teammates and especially injured teammates by seeking revenge particularly in competitive, body-checking leagues. Among female and male players in non-body checking organizations, aggressive play is not reinforced by the social environment. These findings are discussed within the framework of social identity theory and social learning theory, in order to understand players’ need to seek revenge and how the social environment reinforces aggressive behaviors. Conclusion This study provides a better understanding of the players’ motivations and environmental influences around aggressive and violent play which may be conducive to injury. The findings can be used to help design interventions aimed at reducing aggression and related injuries sustained during ice hockey and sports with similar cultures and rules. PMID:27258426

  8. Reliability of Triaxial Accelerometry for Measuring Load in Men's Collegiate Ice-Hockey.

    PubMed

    Van Iterson, Erik H; Fitzgerald, John S; Dietz, Calvin C; Snyder, Eric M; Peterson, Ben J

    2016-08-18

    Wearable microsensor technology incorporating triaxial accelerometry is used to quantify an index of mechanical stress associated with sport-specific movements termed PlayerLoad™. The test-retest reliability of PlayerLoad™ in the environmental-setting of ice-hockey is unknown. The primary aim of this study was to quantify the test-retest reliability of PlayerLoad™ in ice-hockey players during performance of tasks simulating game-conditions. Division I collegiate male ice-hockey players (N=8) wore Catapult Optimeye S5 monitors during repeat performance of 9 ice-hockey tasks simulating game-conditions. Ordered ice-hockey tasks during repeated bouts included: acceleration (forward/backward), 60% top-speed, top-speed (forward/backward), repeated shift circuit, ice-coasting, slap-shot, and bench-sitting. Coefficient of variation (CV), intraclass correlation coefficient (ICC), and minimum differences (MD) were used to assess PlayerLoad™ reliability. Test-retest CVs and ICCs of PlayerLoad™ were: Forward (8.6, 0.54) or backward (13.8, 0.78) acceleration, 60% top-speed (2.2, 0.96), forward (7.5, 0.79) or backwards (2.8, 0.96) top-speed, repeated-shift test (26.6, 0.95), slap-shot (3.9, 0.68), coasting (3.7, 0.98), and bench-sitting (4.1, 0.98), respectively. Raw differences between bouts were not significant for ice-hockey tasks (P>0.05). For each task, between bout raw differences were lower versus MD: Forward (0.06 vs. 0.35) or backward (0.07 vs. 0.36) acceleration, 60% top-speed (0.00 vs. 0.06), forward (0.03 vs. 0.20) or backwards (0.02 vs. 0.09) top-speed, repeated-shift test (0.18 vs. 0.64), slap-shot (0.02 vs. 0.10), coasting (0.00 vs. 0.10), and bench-sitting (0.01 vs. 0.11), respectively. These data suggest PlayerLoad™ demonstrates moderate-to-large test-retest reliability in the environmental-setting of male Division I collegiate ice-hockey. Without previously testing reliability, these data are important as PlayerLoad™ is routinely quantified in

  9. Head injuries in winter sports: downhill skiing, snowboarding, sledding, snowmobiling, ice skating and ice hockey.

    PubMed

    Chaze, Brian; McDonald, Patrick

    2009-02-01

    Winter sports are often associated with high speed, which carries with it the potential for collision. As such, head injuries are among the more commonly encountered injuries in winter-related sporting activities. This article focuses on popular winter sports such as downhill skiing and snowboarding, sledding, snowmobiling, ice skating, and hockey. In virtually all of these activities, the incidence and severity of head injuries can be reduced by the use of appropriate protective headgear.

  10. Head injuries in winter sports: downhill skiing, snowboarding, sledding, snowmobiling, ice skating and ice hockey.

    PubMed

    Chaze, Brian; McDonald, Patrick

    2008-02-01

    Winter sports are often associated with high speed, which carries with it the potential for collision. As such, head injuries are among the more commonly encountered injuries in winter-related sporting activities. This article focuses on popular winter sports such as downhill skiing and snowboarding, sledding, snowmobiling, ice skating, and hockey. In virtually all of these activities, the incidence and severity of head injuries can be reduced by the use of appropriate protective headgear.

  11. Trends in North American Newspaper Reporting of Brain Injury in Ice Hockey

    PubMed Central

    Cusimano, Michael D.; Sharma, Bhanu; Lawrence, David W.; Ilie, Gabriela; Silverberg, Sarah; Jones, Rochelle

    2013-01-01

    The frequency and potential long-term effects of sport-related traumatic brain injuries (TBI) make it a major public health concern. The culture within contact sports, such as ice hockey, encourages aggression that puts youth at risk of TBI such as concussion. Newspaper reports play an important role in conveying and shaping the culture around health-related behaviors. We qualitatively studied reports about sport-related TBI in four major North American newspapers over the last quarter-century. We used the grounded-theory approach to identify major themes and then did a content analysis to compare the frequency of key themes between 1998–2000 and 2009–2011. The major themes were: perceptions of brain injury, aggression, equipment, rules and regulations, and youth hockey. Across the full study period, newspaper articles from Canada and America portrayed violence and aggression that leads to TBI both as integral to hockey and as an unavoidable risk associated with playing the game. They also condemned violence in ice hockey, criticized the administrative response to TBI, and recognized the significance of TBI. In Canada, aggression was reported more often recently and there was a distinctive shift in portraying protective equipment as a solution to TBI in earlier years to a potential contributing factor to TBI later in the study period. American newspapers gave a greater attention to ‘perception of risks’ and the role of protective equipment, and discussed TBI in a broader context in the recent time period. Newspapers from both countries showed similar recent trends in regards to a need for rule changes to curb youth sport-related TBI. This study provides a rich description of the reporting around TBI in contact sport. Understanding this reporting is important for evaluating whether the dangers of sport-related TBI are being appropriately communicated by the media. PMID:23613957

  12. Heart Rate and Energy Expenditure in Division I Field Hockey Players During Competitive Play.

    PubMed

    Sell, Katie M; Ledesma, Allison B

    2016-08-01

    Sell, KM and Ledesma, AB. Heart rate and energy expenditure in Division I field hockey players during competitive play. J Strength Cond Res 30(8): 2122-2128, 2016-The purpose of this study was to quantify energy expenditure and heart rate data for Division I female field hockey players during competitive play. Ten female Division I collegiate field hockey athletes (19.8 ± 1.6 years; 166.4 ± 6.1 cm; 58.2 ± 5.3 kg) completed the Yo-Yo intermittent endurance test to determine maximal heart rate. One week later, all subjects wore a heart rate monitor during a series of 3 matches in an off-season competition. Average heart rate (AvHR), average percentage of maximal heart rate (AvHR%), peak exercise heart rate (PExHR), and percentage of maximal heart rate (PExHR%), time spent in each of the predetermined heart rate zones, and caloric expenditure per minute of exercise (kcalM) were determined for all players. Differences between positions (backs, midfielders, and forwards) were assessed. No significant differences in AvHR, AvHR%, PExHR, PExHR%, and %TM were observed between playing positions. The AvHR% and PExHR% for each position fell into zones 4 (77-93% HRmax) and 5 (>93% HRmax), respectively, and significantly more time was spent in zone 4 compared with zones 1, 2, 3, and 5 across all players (p ≤ 0.05). The kcalM reflected very heavy intensity exercise. The results of this study will contribute toward understanding the sport-specific physiological demands of women's field hockey and has specific implications for the duration and schedule of training regimens.

  13. Scheduling for the National Hockey League Using a Multi-objective Evolutionary Algorithm

    NASA Astrophysics Data System (ADS)

    Craig, Sam; While, Lyndon; Barone, Luigi

    We describe a multi-objective evolutionary algorithm that derives schedules for the National Hockey League according to three objectives: minimising the teams' total travel, promoting equity in rest time between games, and minimising long streaks of home or away games. Experiments show that the system is able to derive schedules that beat the 2008-9 NHL schedule in all objectives simultaneously, and that it returns a set of schedules that offer a range of trade-offs across the objectives.

  14. Trends in reporting of mechanisms and incidence of hip injuries in males playing minor ice hockey in Canada: a cross-sectional study

    PubMed Central

    Ayeni, Olufemi R; Kowalczuk, Marcin; Farag, Jordan; Farrokhyar, Forough; Chu, Raymond; Bedi, Asheesh; Willits, Kevin; Bhandari, Mohit

    2014-01-01

    Background There has been a noted increase in the diagnosis and reporting of sporting hip injuries and conditions in the medical literature but reporting at the minor hockey level is unknown. The purpose of this study is to investigate the trend of reporting hip injuries in amateur ice hockey players in Canada with a focus on injury type and mechanism. Methods A retrospective review of the Hockey Canada insurance database was performed and data on ice hockey hip injuries reported between January 2005 and June 2011 were collected. The study population included all male hockey players from Peewee (aged 11–12 years) to Senior (aged 20+ years) participating in amateur level competition sanctioned by Hockey Canada. Reported cases of ice hockey hip injuries were analyzed according to age, mechanism of injury, and injury subtype. Annual injury reporting rates were determined and using a linear regression analysis trended to determine the change in ice hockey hip injury reporting rate over time. Results One hundred and six cases of ice hockey-related hip injuries were reported in total. The majority of injuries (75.5%) occurred in players aged 15–20 years playing at the Junior level. Most injuries were caused by a noncontact mechanism (40.6%) and strains were the most common subtype (50.0%). From 2005 to 2010, the number of reported hip injuries increased by 5.31 cases per year and the rate of reported hip injury per 1,000 registered players increased by 0.02 cases annually. Conclusion Reporting of hip injuries in amateur ice hockey players is increasing. A more accurate injury reporting system is critical for future epidemiologic studies to accurately document the rate and mechanism of hip injury in amateur ice hockey players. PMID:24966705

  15. Fatness of female field hockey players: Comparison of estimates with different methods.

    PubMed

    Krzykała, M; Konarski, J M; Malina, R M; Rachwalski, K; Leszczyński, P; Ziółkowska-Łajp, E

    2016-06-01

    The aim of the study was to compare relative body fat (% fat) in female field hockey players using several methods with dual-energy X-ray absorptiometry (DXA) as the reference. Participants were 31 Polish hockey players 16-30 years of age, 17 national and 14 youth level. Percent body fat was estimated by DXA (reference method), conventional and segmental bioelectrical impedance analysis (BIA), and predicted from skinfolds (SKF). National and youth team members did not differ in estimated body fat. Correlations between BIA and skinfold estimates of % fat and DXA % fat though significant, were moderate. Both % fat SKF and % fat SBIA differed significantly from % fat DXA, while estimated % fat BIA and % fat DXA did not differ. Limits of agreement were narrow for conventional BIA (-1.20 to 1.71% fat), followed by segmental BIA (3.72-6.09% fat) and broadest for SKF (5.97-9.28% fat). Differences between DXA % fat and estimated % fat with SKF and SBIA increased from the leanest to fattest athletes, whereas conventional BIA overestimated % fat relative to DXA in the small sample of individuals with low relative fatness and underestimated % fat in individuals with elevated relative fatness. Estimated % fat from conventional BIA most closely approximated DXA % fat in this sample of female field hockey players suggesting that the method may be suitable for field surveys to monitor body composition during the season.

  16. Penalty corner routines in elite women's indoor field hockey: prediction of outcomes based on tactical decisions.

    PubMed

    Vinson, Don; Padley, Simon; Croad, Alison; Jeffreys, Mark; Brady, Abbe; James, David

    2013-01-01

    Indoor hockey is a highly competitive international sport, yet no research to date has investigated the key actions within this sport. As with outdoor field hockey, penalty corners represent one of the most likely situations in which goals can be scored. All 36 matches of the round-robin phase of the 2010-2011 England Hockey League Women's Premier Division 'Super Sixes' competition were analysed with the purpose of establishing which factors can predict the scoring of a goal using binary logistic regression analysis. Seventy-two (22.6%) of the 319 observed penalty corners resulted in a goal. The strongest predictor of scoring a goal was taking the penalty corner from the goalkeeper's right. Based on the odds ratio (OR), the odds of the attacking team scoring were 2.27 (confidence interval (CI) = 1.41-3.65) times higher with penalty corners taken from the goalkeeper's right as opposed to the left. Additionally, if the goalkeeper decided to rush to the edge of the circle, the odds of the attacking team failing to score were 2.19 (CI = 1.18-4.08) times higher compared to when the goalkeeper remained near the goal line. These results suggest that strategic decisions from the players and coaches have an important part to play in the success of penalty corners. Future research should investigate the impact of goalkeepers' movement and further examine the technical and tactical intricacies of penalty corners.

  17. An on-ice measurement approach to analyse the biomechanics of ice hockey skating.

    PubMed

    Buckeridge, Erica; LeVangie, Marc C; Stetter, Bernd; Nigg, Sandro R; Nigg, Benno M

    2015-01-01

    Skating is a fundamental movement in ice hockey; however little research has been conducted within the field of hockey skating biomechanics due to the difficulties of on-ice data collection. In this study a novel on-ice measurement approach was tested for reliability, and subsequently implemented to investigate the forward skating technique, as well as technique differences across skill levels. Nine high caliber (High) and nine low caliber (Low) hockey players performed 30 m forward skating trials. A 3D accelerometer was mounted to the right skate for the purpose of stride detection, with the 2nd and 6th strides defined as acceleration and steady-state, respectively. The activity of five lower extremity muscles was recorded using surface electromyography. Biaxial electro-goniometers were used to quantify hip and knee angles, and in-skate plantar force was measured using instrumented insoles. Reliability was assessed with the coefficient of multiple correlation, which demonstrated moderate (r>0.65) to excellent (r>0.95) scores across selected measured variables. Greater plantar-flexor muscle activity and hip extension were evident during acceleration strides, while steady state strides exhibited greater knee extensor activity and hip abduction range of motion (p<0.05). High caliber exhibited greater hip range of motion and forefoot force application (p<0.05). The successful implementation of this on-ice mobile measurement approach offers potential for athlete monitoring, biofeedback and training advice.

  18. The Hockey Stick and the Climate Wars: Dispatches From The Front Lines

    NASA Astrophysics Data System (ADS)

    Mann, M. E.

    2011-12-01

    A central figure in the controversy over human-caused climate change has been The Hockey Stick, a simple, easy-to-understand graph my colleagues and I constructed to depict changes in Earth's temperature back to 1000 AD. The graph was featured in the high-profile Summary for Policy Makers of the 2001 report of the Intergovernmental Panel on Climate Change (IPCC), and it quickly became an icon in the debate over human-caused (anthropogenic) climate change. I will tell the story behind the Hockey Stick, using it as a vehicle for exploring broader issues regarding the role of skepticism in science, the uneasy relationship between science and politics, and the dangers that arise when special economic interests and those who do their bidding attempt to skew the discourse over policy-relevant areas of science. In short, I attempt to use the Hockey Stick to cut through the fog of disinformation that has been generated by the campaign to deny the reality of climate change. It is my intent, in so doing, to reveal the very real threat to our future that lies behind it.

  19. Activity Profile and Between-Match Variation in Elite Male Field Hockey.

    PubMed

    Sunderland, Caroline D; Edwards, Phillip L

    2017-03-01

    Sunderland, CD and Edwards, PL. Activity profile and between-match variation in elite male field hockey. J Strength Cond Res 31(3): 758-764, 2017-This study aimed to (a) provide a position-specific activity profile for elite male hockey players, (b) determine if the activity profile was altered by the introduction of the "self-pass" rule, and (c) provide information relating to match-to-match variability in elite male field hockey. The activity of 28 elite male field hockey players was analyzed over 2 seasons totaling 395 player-match analyses using Global Positioning Satellite technology. Total distance, high-speed running (>15.5 km·h), sprinting (>20 km·h), and mean speed were recorded. Players were categorized into 4 positions: fullback (FB), halfback (HB), midfield (M), and forward (F). Data were analyzed using a 2-way analysis of variance (season, position) and between-match coefficients of variation (CV). The time played differs with position (FB: 65.5 ± 5.3, HB: 49.5 ± 11.5, M: 45.9 ± 7.1, F: 39.5 ± 5.4 minutes; p < 0.0005) and thus affected the activity profile. Total distance covered was greater for fullbacks (FB: 8,001 ± 447, HB: 6,435 ± 1,399, M: 6,415 ± 908, F: 5,844 ± 762 m, p < 0.001), and mean speed and percentage time spent high-speed running and sprinting were greater for forwards than all other positions (HSR: FB: 6.8 ± 1.0, HB: 8.8 ± 1.3, M: 10.7 ± 1.2, F: 13.5 ± 1.8%, p < 0.001). The activity profile did not differ with the introduction of the self-pass. Match-to-match variability (CV) ranged from 5.0% to 22.0% for total and sprint distance, respectively. This is the first study to present an activity profile of elite men's field hockey and its associated variability and demonstrates that each position is unique, and therefore, training and recovery should be position specific.

  20. A Novel Approach to Determine Strides, Ice Contact, and Swing Phases During Ice Hockey Skating Using a Single Accelerometer.

    PubMed

    Stetter, Bernd J; Buckeridge, Erica; von Tscharner, Vinzenz; Nigg, Sandro R; Nigg, Benno M

    2016-02-01

    This study presents a new approach for automated identification of ice hockey skating strides and a method to detect ice contact and swing phases of individual strides by quantifying vibrations in 3D acceleration data during the blade-ice interaction. The strides of a 30-m forward sprinting task, performed by 6 ice hockey players, were evaluated using a 3D accelerometer fixed to a hockey skate. Synchronized plantar pressure data were recorded as reference data. To determine the accuracy of the new method on a range of forward stride patterns for temporal skating events, estimated contact times and stride times for a sequence of 5 consecutive strides was validated. Bland-Altman limits of agreement (95%) between accelerometer and plantar pressure derived data were less than 0.019 s. Mean differences between the 2 capture methods were shown to be less than 1 ms for contact and stride time. These results demonstrate the validity of the novel approach to determine strides, ice contact, and swing phases during ice hockey skating. This technology is accurate, simple, effective, and allows for in-field ice hockey testing.

  1. Examining the relationship between relative age, competition level, and dropout rates in male youth ice-hockey players.

    PubMed

    Lemez, S; Baker, J; Horton, S; Wattie, N; Weir, P

    2014-12-01

    The relative age effect suggests that athletes born in the first two quartiles of a given selection year experience a selection advantage and therefore a greater opportunity for success. We describe two studies examining the relationship between relative age, competition level, and dropout rates of Ontario Minor Hockey Association male ice-hockey players from ages 10 to 15 years (n = 14 325). In Study 1, dropout was highest among players born in quartiles three and four [χ(2) (3) = 16.32, P < 0.05; w = 0.06], while Study 2 found dropped out players to have less movement between competition levels compared to retained players. This study confirms a relationship between relative age and dropout from ice-hockey and adds further depth to our understanding of this persistent phenomenon.

  2. The effects of undergarment composition worn beneath hockey protective equipment on high-intensity intermittent exercise.

    PubMed

    Noonan, Benjamin; Stachenfeld, Nina

    2012-09-01

    The purpose of this study was to examine the impact of undergarment composition worn beneath ice hockey protective equipment on thermal homeostasis and power output, during a cycle ergometer exercise protocol designed to simulate the energy expenditure of a hockey game. We hypothesized that the layers of protective equipment would negate the potential thermoregulatory benefits from synthetic "wicking" undergarments but that subjects may feel more comfortable because of the inherent low moisture retention of these fabrics. Eight men (age, 25.4 ± 1.3 year) performed a repeated sprint test before and after a simulated game under typical hockey conditions (12°C; 82% relative humidity). This test was completed twice while wearing full protective equipment and either synthetic (SYN) or cotton (COT) full-length undergarments. During the simulated game, skin temperatures (34.22 ± 0.20°C vs. 34.46 ± 0.16°C) and core temperatures (37.50 ± 0.13°C vs. 37.59 ± 0.14°C) were similar between SYN and COT, respectively. There were also no significant differences found in sweat loss as a percent of body mass, heart rate, plasma lactate, sprint power, or ratings of perceived exertion between SYN and COT, respectively. The SYN retained less water than COT (140 ± 30 vs. 310 ± 30 g; p < 0.05); however, clothing and protective equipment weight gains as a whole were unaffected by the fabric worn (470 ± 110 vs. 590 ± 80 g) for SYN and COT, respectively. There were minimal differences in thermal sensation and undergarment wetness ratings during the simulated game. Thermoregulation and performance was driven more by properties of the layered protective equipment with minimal effects from undergarment composition.

  3. THE ROLE OF AEROBIC CAPACITY IN HIGH-INTENSITY INTERMITTENT EFFORTS IN ICE-HOCKEY

    PubMed Central

    Roczniok, R.; Maszczyk, A.; Pietraszewski, P.; Zając, A.

    2014-01-01

    The primary objective of this study was to determine a relationship between aerobic capacity (V.O2max) and fatigue from high-intensity skating in elite male hockey players. The subjects were twenty-four male members of the senior national ice hockey team of Poland who played the position of forward or defence. Each subject completed an on-ice Repeated-Skate Sprint test (RSS) consisting of 6 timed 89-m sprints, with 30 s of rest between subsequent efforts, and an incremental test on a cycle ergometer in the laboratory, the aim of which was to establish their maximal oxygen uptake (V.O2max). The analysis of variance showed that each next repetition in the 6x89 m test was significantly longer than the previous one (F5,138=53.33, p<0.001). An analysis of the fatigue index (FI) calculated from the times recorded for subsequent repetitions showed that the value of the FI increased with subsequent repetitions, reaching its maximum between repetitions 5 and 6 (3.10±1.16%). The total FI was 13.77±1.74%. The coefficient of correlation between V.O2max and the total FI for 6 sprints on the distance of 89 m (r =–0.584) was significant (p=0.003). The variance in the index of players’ fatigue in the 6x89 m test accounted for 34% of the variance in V.O2max. The 6x89 m test proposed in this study offers a high test-retest correlation coefficient (r=0.78). Even though the test is criticized for being too exhaustive and thereby for producing highly variable results it still seems that it was well selected for repeated sprint ability testing in hockey players. PMID:25177097

  4. Neuromuscular adaptations to short-term high-intensity interval training in female ice hockey players.

    PubMed

    Kinnunen, Juho-Ville; Piitulainen, Harri; Piirainen, Jarmo M

    2017-03-08

    High-intensity interval training (HIIT) related neuromuscular adaptations, changes in force production and on-ice performance were investigated in female ice-hockey players during pre-season. Fourteen Finnish championship level ice hockey players (average age 22 ± 3 years) participated in 2½-week HIIT. Both spinal (H-reflex) and supraspinal (V-wave) neuromuscular responses of the soleus muscle were recorded before and after the training period. Static jump (SJ) and countermovement jump (CMJ) heights, plantar flexor maximal voluntary contraction (MVC) and rate of force development (RFD) were measured. In addition, soleus and tibialis anterior muscles activations (electromyography; EMG) were measured during MVC and RFD tests. During on-ice training, skating speed and acceleration tests were performed. Subjects significantly improved their plantarflexion MVC force (11.6 ± 11.2%, p < 0.001), RFD (15.2 ± 15.9%, p < 0.01) and SJ (4.8 ± 7.6%, p < 0.05). Voluntary motor drive to the soleus muscle (V-wave amplitude) increased by 16.0 ± 15.4% (p < 0.01) and co-activation of tibialis anterior muscle during the plantar flexion RFD test was reduced by -18.9 ± 22.2% (p < 0.05). No change was observed in spinal α-motoneuron excitability (H-reflex) during MVC or in on-ice performance. These results indicate that HIIT can be used to improve athletes' capability to produce maximal and explosive forces, likely through enhanced voluntary activation of their muscles and reduced antagonist co-activation. Therefore, HIIT can be recommended in pre-season training to improve neuromuscular performance. However, a longer than 2½-week HIIT period is needed to improve on-ice performance in female ice-hockey players.

  5. The impact of a sports vision training program in youth field hockey players.

    PubMed

    Schwab, Sebastian; Memmert, Daniel

    2012-01-01

    The aim of this study was to investigate whether a sports vision training program improves the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training. The choice reaction time task at the D2 board (Learning Task I), the functional field of view task (Learning Task II) and the multiple object tracking (MOT) task (Transfer Task) were assessed before and after the intervention and again six weeks after the second test. Analyzes showed significant differences between the two groups for the choice reaction time task at the D2 board and the functional field of view task, with significant improvements for the intervention group and none for the control group. For the transfer task, we could not find statistically significant improvements for either group. The results of this study are discussed in terms of theoretical and practical implications. Key pointsPerceptual training with youth field hockey playersCan a sports vision training program improve the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training?The intervention was performed in the "VisuLab" as DynamicEye(®) SportsVision Training at the German Sport University Cologne.We ran a series of 3 two-factor univariate analysis of variance (ANOVA) with repeated measures on both within subject independent variables (group; measuring point) to examine the effects on central perception, peripheral perception and choice reaction time.The present study shows an improvement of certain visual abilities with the help of the sports vision training program.

  6. Metabolic power and energy expenditure in an international men's hockey tournament.

    PubMed

    Polglaze, Ted; Dawson, Brian; Buttfield, Alec; Peeling, Peter

    2017-02-20

    The purpose of this study was to ascertain the typical metabolic power characteristics of elite men's hockey, and whether changes occur within matches and throughout an international tournament. National team players (n = 16), divided into 3 positional groups (strikers, midfielders, defenders), wore Global Positioning System devices in 6 matches. Energetic (metabolic power, energy expenditure) and displacement (distance, speed, acceleration) variables were determined, and intensity was classified utilising speed, acceleration and metabolic power thresholds. Midfielder's average metabolic power (11.8 ± 1.0 W · kg(-)(1)) was similar to strikers (11.1 ± 1.3 W · kg(-)(1)) and higher than defenders (10.8 ± 1.2 W · kg(-)(1), P = 0.001). Strikers (29.71 ± 3.39 kJ · kg(-)(1)) expended less energy than midfielders (32.18 ± 2.67 kJ · kg(-)(1), P = 0.014) and defenders (33.23 ± 3.96 kJ · kg(-)(1), P < 0.001). Energetic variables did not change between halves or across matches. Across all positions, over 45% of energy expenditure was at high intensity (>20 W · kg(-)(1)). International hockey matches are intense and highly intermittent; however, intensity is maintained throughout matches and over a tournament. In isolation, displacement measures underestimate the amount of high-intensity activity, whereas the integration of instantaneous speed and acceleration provides a more comprehensive assessment of the demands for variable-speed activity typically occurring in hockey matches.

  7. Effect of Increasing Maximal Aerobic Exercise on Serum Muscles Enzymes in Professional Field Hockey Players

    PubMed Central

    Hazar, Muhsin; Otağ, Aynur; Otağ, İlhan; Sezen, Mehmet; Sever, Ozan

    2015-01-01

    Background and Objectives: Exercise results in oxidative enzyme increase and micro-injuries in skeletal muscles. The aim of this study was to investigate the effect of maximal aerobic exercise on serum muscle enzymes in professional field hockey players. This study aims to determine the effect of increasing maximal aerobic exercise on creatine kinase (CK), creatine kinase-MB (CK-MB), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) serum levels. Material and Methods: 31 young professional field hockey players (13 female and 18 male players) volunteered for this study. All participants underwent the shuttle run test. Blood samples were taken from each participant before the shuttle run test. Post test blood samples were taken immediately after exercise and one hour after respectively. Pre and post test CK, CK-MB, AST and ALT values were measured by means of auto analyzer using original kits. Results: The acute post test measure of the CK level increased in male (p=0.002) and female (p=0.00) sportsmen. CK-MB values obtained one hour after the exercise was lower than those before the exercise in males (p=0.02). In females (p=0.017) and males (p=0.05) AST activity significantly increased immediately after exercise and decreased to resting activity 1 h recovery. ALT significantly increased immediately after exercise in female (p=0.03) and male (p=0.00) athletes and after 1 h recovery ALT activities decreased below resting values. Conclusion: The timing and severity of exercise used in our study increased CK values, decreased CK-MB values and AST, ALT values increased in female and male field hockey players. PMID:25948428

  8. The Impact of a Sports Vision Training Program in Youth Field Hockey Players

    PubMed Central

    Schwab, Sebastian; Memmert, Daniel

    2012-01-01

    The aim of this study was to investigate whether a sports vision training program improves the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training. The choice reaction time task at the D2 board (Learning Task I), the functional field of view task (Learning Task II) and the multiple object tracking (MOT) task (Transfer Task) were assessed before and after the intervention and again six weeks after the second test. Analyzes showed significant differences between the two groups for the choice reaction time task at the D2 board and the functional field of view task, with significant improvements for the intervention group and none for the control group. For the transfer task, we could not find statistically significant improvements for either group. The results of this study are discussed in terms of theoretical and practical implications. Key pointsPerceptual training with youth field hockey playersCan a sports vision training program improve the visual performance of youth male field hockey players, ages 12 to 16 years, after an intervention of six weeks compared to a control group with no specific sports vision training?The intervention was performed in the “VisuLab” as DynamicEye® SportsVision Training at the German Sport University Cologne.We ran a series of 3 two-factor univariate analysis of variance (ANOVA) with repeated measures on both within subject independent variables (group; measuring point) to examine the effects on central perception, peripheral perception and choice reaction time.The present study shows an improvement of certain visual abilities with the help of the sports vision training program. PMID:24150071

  9. Development and Validation of a Method for Determining Tridimensional Angular Displacements with Special Applications to Ice Hockey Motions.

    ERIC Educational Resources Information Center

    Gagnon, Micheline; And Others

    1983-01-01

    A method for determining the tridimensional angular displacement of skates during the two-legged stop in ice hockey was developed and validated. The angles were measured by geometry, using a cinecamera and specially equipped skates. The method provides a new tool for kinetic analyses of skating movements. (Authors/PP)

  10. Effects of Carbohydrate Intake Before and During An Ice Hockey Game on Blood and Muscle Energy Substrates.

    ERIC Educational Resources Information Center

    Simard, Clermont; And Others

    1988-01-01

    Study of the effect of a supplemental carbohydrate intake for seven elite ice hockey players before and during a game demonstrated that the supplement could result in less glycogen usage per distance skated, which had important implications for athletes who may participate in more than one game a day. (Author/CB)

  11. Proprioception of foot and ankle complex in young regular practitioners of ice hockey, ballet dancing and running.

    PubMed

    Li, Jing Xian; Xu, Dong Qing; Hoshizaki, Blaine

    2009-01-01

    This study examined the proprioception of the foot and ankle complex in regular ice hockey practitioners, runners, and ballet dancers. A total of 45 young people with different exercise habits formed four groups: the ice hockey, ballet dancing, running, and sedentary groups. Kinesthesia of the foot and ankle complex was measured in plantarflexion (PF), dorsiflexion (DF), inversion (IV), and eversion (EV) at 0.4 degrees /s using a custom-made device. The results showed the following: (1) significantly better perceived passive motion sense in PF/DF was found as compared with the measurements in IV/EV within each group (P < .01); (2) ice hockey and ballet groups perceived significantly better passive motion sense in IV/EV than the running (P < .05) and the sedentary (P < .01) groups; and (3) no significant difference in the all measurements was found between running and sedentary groups. The benefits of ice hockey and ballet dancing on proprioception may be associated with their movement characteristics.

  12. Effects of Short Term Camp Periods on Aerobic and Anaerobic Performance Parameters in Ice Hockey National Team Athletes

    ERIC Educational Resources Information Center

    Eler, Serdar

    2016-01-01

    This study was conducted for determining the effects of trainings, applied to athletes during short term camp period, on their aerobic and anaerobic performance. Measurements were made by the participation of 28 volunteer male ice hockey national team players. During the 15-day camp period, 10-minute running and stretching for warming and then…

  13. Enforcement of Mouthguard Use and Athlete Compliance in National Collegiate Athletic Association Men's Collegiate Ice Hockey Competition.

    ERIC Educational Resources Information Center

    Hawn, Kristen L.; Visser, Mary Frances; Sexton, Patrick J.

    2002-01-01

    Investigated enforcement patterns and athlete compliance with the National Collegiate Athletic Association rule requiring the wearing of mouthguards in men's collegiate ice hockey games during one season. Surveys of athletic trainers indicated that the use of mouthguards in competition was not consistently enforced by athletic trainers, coaches,…

  14. “I Went to a Fight the Other Night and a Hockey Game Broke Out”

    PubMed Central

    Goldschmied, Nadav; Espindola, Samantha

    2013-01-01

    Background: The current study explored the relationship between fighting behavior and passage of time, across games and seasons, in an attempt to assess if violent behavior in hockey is impulsive or intentional. Hypothesis: Before engaging in fighting behavior, players assess the utility of their actions and thus will fight less when the game is on the line (third period) and when champions are crowned (postseason). Methods: An archival exploration utilizing open access databases from multiple Internet sources. Results: During the 2010-2011 National Hockey League (NHL) season, players were significantly less likely to be involved in a fight as the game was coming to a close than in its early stages. In addition, data from the past 10 NHL seasons showed that players were significantly more violent in preseason games than during the regular season. They were also least likely to be involved in a fight during the postseason. Conclusion: The converging evidence suggests that players take into account the penalties associated with fighting and are less likely to engage in violence when the stakes are high, such as at the end of a game or a season. This implies, in turn, that major acts of aggression in the league are more likely to be calculated rather than impulsive. The findings suggest that a more punitive system should diminish fighting behavior markedly. PMID:24427418

  15. Spinal cord injuries in ice hockey in Finland and Sweden from 1980 to 1996.

    PubMed

    Mölsä, J J; Tegner, Y; Alaranta, H; Myllynen, P; Kujala, U M

    1999-01-01

    Traumatic spinal cord injury (SCI) in the cervical or thoracic region is one of the most catastrophic types of sport injuries. This study was designed to determine incidence and mechanisms of major SCI in ice hockey in Finland and Sweden from 1980 to 1996 in order to find possibilities for prevention. Retrospective analysis of injury occurrence were carried out. Medical case records were reviewed and injured players were interviewed to complete the data. From 1980 to 1996, there were 16 accidents involving spinal cord injury with permanent disability. All players were male. The mean age was 21.1 years (range = 14 to 33 yr). In 50% of the cases the mechanism was body checking from behind and a blow to the head from the boards. In 69% of the cases the vertebral injury was fracture or/and luxation between C5 and C7. The neurological endstate was tetraplegia/paresis in 10 cases and paraplegia/paresis of the lower extremities in 6 cases. Ice hockey is one of the most popular sports in Europe, and the number of participants is still increasing. The typical mechanism in SCI is body checking from behind, falling down and a head-first blow from the boards. These serious injuries may be prevented by changing the rules (banning body checking near the boards) with strict refereeing and education of trainers and players.

  16. Carbon monoxide in indoor ice skating rinks: Evaluation of absorption by adult hockey players

    SciTech Connect

    Levesque, B.; Dewailly, E.; Lavoie, R.; Prud'Homme, D.; Allaire, S. )

    1990-05-01

    We evaluated alveolar carbon monoxide (CO) levels of 122 male, adult hockey players active in recreational leagues of the Quebec City region (Canada), before and after 10 weekly 90-minute games in 10 different rinks. We also determined exposure by quantifying the average CO level in the rink during the games. Other variables documented included age, pulmonary function, aerobic capacity, and smoking status. Environmental concentrations varied from 1.6 to 131.5 parts per million (ppm). We examined the absorption/exposure relationship using a simple linear regression model. In low CO exposure levels, physical exercise lowered the alveolar CO concentration. However, we noted that for each 10 ppm of CO in the ambient air, the players had adsorbed enough CO to raise their carboxyhemoglobin (COHb) levels by 1 percent. This relationship was true both for smokers and non-smokers. We suggest that an average environmental concentration of 20 ppm of CO for the duration of a hockey game (90 minutes) should be reference limit not to be exceeded in indoor skating rinks.

  17. Bebop on the Hockey Pitch: Cross-Disciplinary Creativity and Skills Transfer.

    PubMed

    Harrison, Clive M

    2016-01-01

    This paper generalizes task-specific (but dissimilar) skills, from the jazz concert stage and from the hockey field, into the domain of creativity research. What is sought are clues to what skills or creativities are transferable across dissimilar domains. It is argued that certain domain-general skills are transferable across domains, but a domain-general or 'c' creative capacity, is not. Rather than transferring some over-arching capacity to be universally creative, this research highlights factors likely to facilitate successful cross-disciplinary creative expression and posits a correlation between the capacities for discriminant pattern-recognition, task-specific expertise, and sensory data-collection, and the transferability of creativity. Of particular significance is the capacity for informed, selective pattern-breaking based on the 'depth' or 'insider' perspective of the domain expert; such 'expert variation and selective retention' provides creative choices and responses that are likely to be perceived by the field as creative: valuable, novel and surprising. The author is a renowned Australian studio bassist, jazz musician, and music educator who also plays field hockey for Australia at Masters level. His recently completed Ph.D. thesis, based on a performance and composition career spanning 46 years, takes the form of an analytical autoethnography drawn from personal field notes, diaries and interviews as well as published record albums.

  18. A Preliminary Exploration of Concussion and Strength Performance in Youth Ice Hockey Players.

    PubMed

    Reed, N; Taha, T; Monette, G; Keightley, M

    2016-08-01

    The objective of this study was to describe the effect of concussion on upper and lower body strength in children and youth athletes. The participant group was made up of 178 unique male and female ice hockey players (ages 8-14 years). Using a 3-year prospective longitudinal research design, baseline and post-concussion data on hand grip strength, jump tests, and leg maximal voluntary contraction were collected. Using a linear mixed-effects model, no significant differences were found when comparing the baseline strength performance of individuals who went on to experience a concussion and those who did not. When accounting for sex, multiple concussions, and ongoing changes in strength associated with age, weaker hand grip scores were found following concussion while participants were still symptomatic. Lower squat jump heights were achieved while participants were symptomatic as well as when they were no longer self-reporting symptoms associated with concussion. This study represents an initial step towards better understanding strength performance following concussion that may limit the on and off ice performance of youth ice hockey players, as well as predispose youth to subsequent injuries.

  19. Bebop on the Hockey Pitch: Cross-Disciplinary Creativity and Skills Transfer

    PubMed Central

    Harrison, Clive M.

    2016-01-01

    This paper generalizes task-specific (but dissimilar) skills, from the jazz concert stage and from the hockey field, into the domain of creativity research. What is sought are clues to what skills or creativities are transferable across dissimilar domains. It is argued that certain domain-general skills are transferable across domains, but a domain-general or ‘c’ creative capacity, is not. Rather than transferring some over-arching capacity to be universally creative, this research highlights factors likely to facilitate successful cross-disciplinary creative expression and posits a correlation between the capacities for discriminant pattern-recognition, task-specific expertise, and sensory data-collection, and the transferability of creativity. Of particular significance is the capacity for informed, selective pattern-breaking based on the ‘depth’ or ‘insider’ perspective of the domain expert; such ‘expert variation and selective retention’ provides creative choices and responses that are likely to be perceived by the field as creative: valuable, novel and surprising. The author is a renowned Australian studio bassist, jazz musician, and music educator who also plays field hockey for Australia at Masters level. His recently completed Ph.D. thesis, based on a performance and composition career spanning 46 years, takes the form of an analytical autoethnography drawn from personal field notes, diaries and interviews as well as published record albums. PMID:26903926

  20. Bidirectional reflectance spectroscopy 7. The single particle phase function hockey stick relation

    NASA Astrophysics Data System (ADS)

    Hapke, Bruce

    2012-11-01

    The measured volume-average single particle angular scattering functions of a large number of types of particle of interest for planetary regoliths in the visible-near-IR wavelength region can be represented to a reasonable approximation by two-parameter, double Henyey-Greenstein functions. When the two parameters of this function are plotted against one another they are found to be inversely correlated and lie within a restricted zone shaped like a hockey stick within the parameter space. The centroid of the zone is a curve that can be represented by a simple empirical equation. The wide variety of types of particles used to construct the plot implies that this equation may represent most of the particles found in regoliths. This means that when modeling the bidirectional reflectance of a regolith it may be possible to reduce the number of parameters necessary to specify the reflectance, and also to characterize the entire single particle phase function from observations at phase angles less than 90°. Even if the hockey stick relation has a finite width, rather than being a line, it restricts the parameter space that must be searched when fitting data. The curve should also be useful for forward modeling particle phase functions.

  1. An experiment to evaluate carbon monoxide absorption by hockey players in ice skating rinks.

    PubMed

    Levesque, B; Lavoie, R; Dewailly, E; Prud'homme, D; Allaire, S

    1991-02-01

    Carbon monoxide (CO) released from the exhaust of ice resurfacing machinery is frequently found in indoor ice skating rinks. We conducted a study with 14 male adult non-smokers unexposed occupationally, who played hockey games in 4 different atmospheric CO concentrations. To document absorption, we measured their alveolar CO (alvCO). Exposure was the average CO level in the rink during the game. Environmental concentrations were between 0.0 (undetected) and 76.2 parts per million (ppm). The exposure-absorption relationship was linear (regression parameters: r2 = 0.93, slope = 0.411, intercept = -1.45). This means that for each 10 ppm of CO in the indoor air, the players absorbed enough CO to raise their alvCO by 4.1 ppm (approximately 0.76% carboxyhemoglobin). Taking into account the duration of the games, the regression coefficients were almost similar to those of an earlier study we made with 122 adult male hockey players playing in recreational leagues of the Quebec city area. These results show the exposure-absorption relationship for an acute 60-minute exposure, in a design which eliminated certain of the uncontrolled variables of our first study. It also emphasizes the importance of prevention for CO pollution in indoor skating rinks.

  2. Practicing Field Hockey Skills Along the Contextual Interference Continuum: A Comparison of Five Practice Schedules

    PubMed Central

    Cheong, Jadeera Phaik Geok; Lay, Brendan; Grove, J. Robert; Medic, Nikola; Razman, Rizal

    2012-01-01

    To overcome the weakness of the contextual interference (CI) effect within applied settings, Brady, 2008 recommended that the amount of interference be manipulated. This study investigated the effect of five practice schedules on the learning of three field hockey skills. Fifty-five pre-university students performed a total of 90 trials for each skill under blocked, mixed or random practice orders. Results showed a significant time effect with all five practice conditions leading to improvements in acquisition and learning of the skills. No significant differences were found between the groups. The findings of the present study did not support the CI effect and suggest that either blocked, mixed, or random practice schedules can be used effectively when structuring practice for beginners. Key pointsThe contextual interference effect did not surface when using sport skills.There appears to be no difference between blocked and random practice schedules in the learning of field hockey skills.Low (blocked), moderate (mixed) or high (random) interference practice schedules can be used effectively when conducting a multiple skill practice session for beginners. PMID:24149204

  3. Development of a hockey-specific, skate-treadmill VO2 max protocol.

    PubMed

    Dreger, R W; Quinney, H A

    1999-12-01

    The purpose of this study was to investigate a protocol for the determination of VO2 max utilizing a motor-driven skate treadmill (ST). On separate days, 6 male hockey players completed a ST and a cycle ergometer (BK) VO2 max protocol. The results showed no significant difference between the ST and BK protocols for relative (60.4 +/- 5.09 vs. 59.0 +/- 8.31 ml.kg-1.min-1) and absolute VO2 max values (4.51 +/- 0.50 vs. 4.39 +/- 0.59 L.min-1), respectively. Significantly higher HR max was recorded during the ST protocol (202.3 +/- 4.27 vs. 200.7 +/- 4.55 b.min-1) (p < 0.05). Peak VE and VT were nonsignificant between the two conditions. However, peak f was higher for the ST protocol (63.0 +/- 7.56 vs. 60.2 +/- 7.76 breath.min-1) (p < 0.05). Although the physiological response to both protocols was similar, the ST protocol replicates a hockey stride, which may provide more applicable information for the development of training programs.

  4. Division I Hockey Players Generate More Power Than Division III Players During on- and Off-Ice Performance Tests.

    PubMed

    Peterson, Ben J; Fitzgerald, John S; Dietz, Calvin C; Ziegler, Kevin S; Ingraham, Stacy J; Baker, Sarah E; Snyder, Eric M

    2015-05-01

    Current research has found anthropometric and physiological characteristics of hockey players that are correlated to performance. These characteristics, however, have never been examined to see whether significant differences exist between on- and off-ice performance markers at different levels of play; Division I, Elite Junior, and Division III. The purpose of this study was to examine the differences that may exist between these characteristics in Division I (24), Elite Junior (10), and Division III hockey (11) players. Forty-five (age: 18-24 years) hockey players completed anthropometric, on-ice, and off-ice tests to ascertain average measures for each division of play. On-ice testing was conducted in full hockey gear and consisted of acceleration, top-speed, and on-ice repeated shift test (RST). Off-ice tests included vertical jump, Wingate, grip strength, and a graded exercise test performed on a skating treadmill to ascertain their (Equation is included in full-text article.). Division I players had significantly lower body fat than their Division III peers (p = 0.004). Division I players also scored significantly better on measures of anaerobic power; vertical jump (p = 0.001), Wingate peak power (p = 0.05), grip strength (p = 0.008), top speed (p = 0.001), and fastest RST course time (p = 0.001) than their Division III counterparts. There was no significant difference between Division I and Elite Junior players for any on- or off-ice performance variable. The results of this study indicate that performance differences between Division I and Division III hockey players seem to be primarily because of the rate of force production.

  5. A Cool Sport Full of Physics

    ERIC Educational Resources Information Center

    Hache, Alain

    2008-01-01

    Of all sports, ice hockey is possibly the one with the widest array of physics elements in it. The game provides many examples that can bring physics to life in the classroom. Ice hockey (or just "hockey" as many Canadians would say) sees athletes sliding on ice at high speeds and in various ways, shooting and slapping pucks, and…

  6. Magnetic Resonance Imaging and Intra-articular Findings After Anterior Cruciate Ligament Injuries in Ice Hockey Versus Other Sports

    PubMed Central

    Kluczynski, Melissa A.; Kang, Jeansol V.; Marzo, John M.; Bisson, Leslie J.

    2016-01-01

    Background: The prevalence of comorbid knee pathology has been examined for sports-related anterior cruciate ligament (ACL) injuries, but it has not been examined in ice hockey players. Purpose: To compare concomitant bone bruising, collateral ligament injuries, and intra-articular injuries in ACL injuries suffered during ice hockey versus other sports. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 20 patients with ACL injuries sustained during ice hockey were identified from a prospective registry, of which 95% were male and 90% had a contact mechanism of injury (MOI). Thirteen cases and 46 controls who sustained ACL injuries from ice hockey and other sports, respectively, were included. Inclusion criteria for cases and controls were male sex, contact MOI, no prior knee surgery, magnetic resonance imaging (MRI) within 6 weeks of injury, and surgery within 3 months of injury. Age, body mass index (BMI), MRI findings (bone bruising, medial and lateral collateral ligament [MCL, LCL] injuries), and arthroscopic findings (meniscus tears, chondral injuries) were compared for cases versus controls using t tests or exact chi-square tests. Results: Age (22.9 ± 8.8 vs 23.4 ± 10.4 years, P = .88) and BMI ≥25 kg/m2 (50% vs 65.9%, P = .66) did not differ between cases and controls. Cases had less lateral bone bruising (lateral femoral condyle: 54.6% vs 93%, P = .01; lateral tibial plateau: 72.7% vs 93%, P = .09) and no medial bone bruising (medial femoral condyle: 0% vs 7%, P = .06; medial tibial plateau: 0% vs 32.6%, P = .05) compared with controls. Cases had less frequent lateral meniscus tears than controls (23.1% vs 58.5%, P = .05). There were no significant differences in MCL (40% vs 31.2%, P = .77), LCL (0% vs 3.9%, P > .999), medial meniscus tears (7.7% vs 37%, P = .08), and chondral injuries (10% vs 9.4%, P > .999) for cases versus controls. Conclusion: Male ice hockey players with ACL injuries had less lateral femoral condyle and

  7. CHRONIC LEG PAIN IN A DIVISION II FIELD HOCKEY PLAYER: A CASE REPORT

    PubMed Central

    Snowden, Julie; Becker, Jonathan A.; Hazle, Charles

    2014-01-01

    Exertional compartment syndromes in athletes represent a diagnostic and management challenge for clinicians. The clinical presentation of exertional compartment syndrome is similar to other more common musculoskeletal disorders. A lack of special tests or unique diagnostic identifiers for use in decision making by out‐patient clinicians complicates early recognition of this disorder and may delay optimal management. The purpose of this case report is to retrospectively explore the clinical presentation and the decision‐making during the course of care of a field hockey athlete eventually determined to have exertional compartment syndrome. Suggestions to assist in recognition and guidance in patient management are included as well as the procedures required for differential diagnosis. Procedures utilized during conservative care are also described in detail. Level of Evidence: 5 (Single Case Report) PMID:24567863

  8. Role of energy systems in two intermittent field tests in women field hockey players.

    PubMed

    Lemmink, Koen A P M; Visscher, Susan H

    2006-08-01

    The energetics of 2 field tests that reflect physical performance in intermittent sports (i.e., the Interval Shuttle Sprint Test [ISST] and the Interval Shuttle Run Test [ISRT]) were examined in 21 women field hockey players. The ISST required the players to perform 10 shuttle sprints starting every 20 seconds. During the ISRT, players alternately ran 20-m shuttles for 30 seconds and walked for 15 seconds with increasing speed. Anaerobic and aerobic power tests included Wingate cycle sprints and a .V(O2)max cycle test, respectively. Based on correlation and regression analyses, it was concluded that for the ISST, anaerobic energetic pathways contribute mainly to energy supply for peak sprint time, while aerobic energetic pathways also contribute to energy supply for total sprint time. Energy during the ISRT is supplied mainly by the aerobic energy system. Depending on the aspect of physical performance a coach wants to determine, the ISST or ISRT can be used.

  9. Stages and demands in the careers of Canadian National Hockey League players.

    PubMed

    Battochio, Randy C; Stambulova, Natalia; Schinke, Robert J

    2016-01-01

    Researchers have identified some demands of Canadian National Hockey League (NHL) players, yet there is little direction for players hoping to reach the lucrative league. The objectives of this study were to identify the stages, statuses and demands in Canadian NHL players' careers and propose an empirical career model of Canadian NHL players. In total, 5 rookies, 5 veterans and 13 retirees had their interviews undergo an interpretive thematic analysis. Prospects face the NHL combine, training camp and minor league assignment. While developing into NHL players, rookies deal with NHL call-ups, team competition and formative production while sophomores seemed preoccupied by the opposition. Prime veterans become All-Stars by garnering point production and challenging for the Stanley Cup while seasoned veterans remain relevant through training camps. A discussion about the model's viability is followed by applications for sport psychology researchers and practitioners.

  10. Trait aggressiveness and hockey penalties: predicting hot tempers on the ice.

    PubMed

    Bushman, B J; Wells, G L

    1998-12-01

    Previous studies examining the validity of measures of trait aggressiveness either have been retrospective studies or have used laboratory aggression as the criterion behavior. Can a measure of trait aggressiveness predict nonlaboratory physical aggression? The Physical Aggression subscale of the Aggression Questionnaire was completed by 91 high school hockey players prior to the start of the season. At the end of the season, these trait aggressiveness scores were regressed on minutes in the penalty box for aggressive penalties (e.g., fighting, slashing, tripping) and minutes in the penalty box for nonaggressive penalties (e.g., delay of game, illegal equipment, too many players). As expected, preseason trait aggressiveness scores predicted aggressive penalty minutes (r = .33) but not nonaggressive penalty minutes (r = .04).

  11. Septic olecranon and prepatellar bursitis in hockey players: a report of three cases

    PubMed Central

    Tuff, Taylor; Chrobak, Karen

    2016-01-01

    Septic bursitis (SB) is an important differential diagnosis in athletes presenting with an acute subcutaneous swelling of the elbow or knee. Prompt recognition is essential to minimize recovery time and prevent the spread of infection. Due to the significant overlap in clinical features, it is often difficult to differentiate SB from non-septic bursitis (NSB) without bursal aspirate analysis. SB is commonly not considered unless the bursitis is accompanied by a local skin lesion or fever. This study describes two cases of septic olecranon bursitis and one case of septic prepatellar bursitis in adult hockey players presenting to a sports medicine clinic. None of the cases presented with an observable skin lesion and only one case developed a fever. It is therefore essential that clinicians maintain a high index of suspicion and monitor for signs of progression when presented with an acute bursitis even in the absence of these features. PMID:28065991

  12. An examination of the cohesion-performance relationship in university hockey teams.

    PubMed

    Slater, M R; Sewell, D F

    1994-10-01

    The objective of this study was to assess, using the Group Environment Questionnaire, whether team cohesion in university-level field hockey was a cause for, or an effect of, successful performance. A quasi-experimental longitudinal design with cross-lagged correlational analysis was adopted and measures of cohesion and performance were taken midway and later in the season. The results of the synchronous correlations showed a positive relationship (with good stationarity) between team cohesion and performance outcome. Although non-significant cross-lagged differentials indicated a circular relationship, the magnitudes of both the cross-lagged correlations and the partial correlations, together with multiple-regression analyses, revealed that the stronger flow was from cohesion to performance. The socially oriented aspects of cohesion, in particular, had significant associations with performance. The results imply that cohesion-performance relationships should be examined within a circular model, in which cohesion and performance are interdependent.

  13. Septic olecranon and prepatellar bursitis in hockey players: a report of three cases.

    PubMed

    Tuff, Taylor; Chrobak, Karen

    2016-12-01

    Septic bursitis (SB) is an important differential diagnosis in athletes presenting with an acute subcutaneous swelling of the elbow or knee. Prompt recognition is essential to minimize recovery time and prevent the spread of infection. Due to the significant overlap in clinical features, it is often difficult to differentiate SB from non-septic bursitis (NSB) without bursal aspirate analysis. SB is commonly not considered unless the bursitis is accompanied by a local skin lesion or fever. This study describes two cases of septic olecranon bursitis and one case of septic prepatellar bursitis in adult hockey players presenting to a sports medicine clinic. None of the cases presented with an observable skin lesion and only one case developed a fever. It is therefore essential that clinicians maintain a high index of suspicion and monitor for signs of progression when presented with an acute bursitis even in the absence of these features.

  14. Watching a previous victory produces an increase in testosterone among elite hockey players.

    PubMed

    Carré, Justin M; Putnam, Susan K

    2010-04-01

    Previous research indicates that testosterone concentrations are highly responsive to human competitive interactions and that winners have elevated testosterone concentrations relative to losers. Also, there is some evidence that simply observing others compete can have a similar effect on the endocrine system. Here, in two studies, we examined the extent to which elite male hockey players would demonstrate an increase in testosterone concentrations after watching themselves engaged in a previous successful competitive interaction. Results indicated that watching a previous victory produced a significant increase in testosterone concentrations (42-44% increase), whereas watching a previous defeat or a neutral video did not produce a significant change in testosterone (17% and 6%, respectively). Given that natural fluctuations in testosterone have been shown to influence future competitive and aggressive behaviours, the current studies may have important practical implications for individuals involved in competitive sports.

  15. Cardiovascular Prevention in a High Risk Sport, Ice Hockey: Applications in Wider Sports Physical Therapy Practice

    PubMed Central

    2006-01-01

    Although acute myocardial infarction and sudden cardiac death are relatively rare occurrences in athletics, cardiovascular accidents do occur. This manuscript presents information on the cardiovascular risks in athletics. In addition, information is provided on screening for cardiovascular risk – including history taking, chart review, physical examination – and the appropriate guidelines on the treatment of athletes found to be at risk. For the purpose of this article, the sport of ice hockey is used to illustrate the subject matter and highlight the behaviors in sport that carry cardiovascular risk. Physical therapists have ethical and legal responsibility to undertake the necessary screening procedures to recognize and respond to any signs of cardiovascular risk in their clients. PMID:21522221

  16. Recreational ice hockey injuries in adult non-checking leagues: a United States perspective.

    PubMed

    Caputo, Pasqualino; Mattson, Douglas J

    2005-03-01

    The purpose of this study was to analyze injuries among adult recreational ice hockey players. This was an observational prospective cohort study with data collected on injuries sustained during one season in the adult recreational ice hockey leagues of Oneida County, NY. The injury incidence rate was found to be 12.2/1000 player-exposures. The most common anatomic region injured was the head/neck/face (35%). Collisions were most often reported as the mechanism of injury (44%). Fracture was the most common diagnosis. Of players wearing face protection (full cage or shield, or partial visor/half shield), none suffered facial injuries, while all facial injuries reported were to players not wearing facial protection. The concussion rate was 1.1/1000 player-exposures. A lack of protective equipment was associated with 38% of injuries and 24% of injuries involved penalties. A history of prior injuries was found in 89% of injured players with 28% re-injuring the same body part. This study's findings suggested various strategies to address player injuries such as mandatory full facial protection and shoulder pads, strict enforcement of game rules, and game rule modifications (no body checking). Further research is needed on the role of preventive rehabilitation in players with previous injury history. Key PointsThe injury incidence rate was found to be 12.2/1000 player-exposures, similar to previous Canadian literature.The concussion rate was 1.1/1000 player-exposures.38% of injuries involved a lack of protective equipment and 24% of injuries involved penalties.Full facial protection and shoulder pads should be compulsory.Strict enforcement of game rules is necessary.History of prior injuries was found in 89% of injured players.

  17. Examining social identity and intrateam moral behaviours in competitive youth ice hockey using stimulated recall.

    PubMed

    Bruner, Mark W; Boardley, Ian D; Allan, Veronica; Root, Zach; Buckham, Sara; Forrest, Chris; Côté, Jean

    2016-10-13

    Social identity - identity formed through membership in groups - may play an important role in regulating intrateam moral behaviour in youth sport (Bruner, M. W., Boardley, I., & Côté, J. (2014). Social identity and prosocial and antisocial behavior in youth sport. Psychology of Sport and Exercise, 15(1), 56-64. doi:10.1016/j.psychsport.2013.09.003). The aim of this study was to qualitatively examine this potential role through stimulated recall interviews with competitive youth-ice-hockey players. Twenty-three players (Mage = 13.27 years, SD = 1.79) who reported engaging in high, median or low frequency of antisocial teammate behaviour (determined through pre-screening with the Prosocial and Antisocial Behaviour in Sport Scale [Kavussanu, M., & Boardley, I. D. (2009). The prosocial and antisocial behavior in sport scale. Journal of Sport and Exercise Psychology, 31(1), 97-117. doi:10.1123/jsep.31.1.97]) were recruited from eight youth-ice-hockey teams in Canada. Interviews involved participants recalling their thoughts during prosocial/antisocial interactions with teammates, prompted by previously recorded video sequences of such incidents. Thematic analysis of interview data revealed all athletes - regardless of reported frequency of intrateam antisocial behaviour - felt prosocial interactions with teammates enhanced social identity. In contrast, the perceived influence of antisocial teammate behaviour on social identity differed depending on athletes' reported frequency of intrateam antisocial behaviour; those reporting low and median frequencies described how such behaviour undermines social identity, whereas athletes reporting high frequency did not perceive this effect. The study findings highlight the potential importance of intrateam moral behaviour and social identity for youth-sport team functioning.

  18. In situ removal of the ``hockey stick`` fissile material deposit at the East Tennessee Technology Park

    SciTech Connect

    Lewis, K.D.; Tollefson, D.A.

    1998-12-31

    Prior to shutdown of the gaseous diffusion process at the Oak Ridge K-25 Plant (now East Tennessee Technology Park), leakage of humid air into the process piping and equipment caused reactions with UF{sub 6}, which produced nonvolatile uranyl fluoride (UO{sub 2}F{sub 2}) deposition and other solid uranium fluoride compounds. During the period 1988--1991, Lockheed Martin Energy Systems performed nondestructive analysis (NDA) radiological surveys of the K-25 Site process facilities that previously had contained or processed uranium. These surveys were made to estimate the mass and {sup 235}U assay of localized uranium deposits remaining within the process piping and equipment. Three deposits were identified that had sufficient mass to achieve criticality. Two of these, the horizontal pipe and the T pipe deposits, required the addition of a moderator before a criticality accident could occur. The third was a very large uranium deposit determined by NDA to be distributed annularly in the process piping. Because of the shape of the system, it came to be called the hockey stick deposit. Because of the foregoing concerns with the hockey stick deposit, it was decided to gain experience by removing the less hazardous smaller deposits with their less complicated geometries first. Thus, the horizontal pipe deposit, the simplest and least reactive case, was handled first, in June 1997. Next, the T pipe, which was an intersection of large-diameter pipes and which posed additional problems because of a more complex geometry, was handled in August 1997. From this experience, the deposit removal techniques and procedures were refined. In December 1997, this large deposit was removed, and the contents were placed in a safe array configuration.

  19. Do Canadian collegiate hockey players accurately perceive body composition changes after unmonitored training and diet?

    PubMed

    Prokop, Neal W; Duncan, Lindsay R; Andersen, Ross E

    2015-10-01

    Collegiate athletes often use nutritional programs and supplements to elicit body composition changes in muscle or fat. It is unknown if athletes can accurately perceive their fluctuations in body composition, yet their understanding may help them make more accurate interpretations regarding the success of potential nutrition or exercise regimens. The purpose of this study was to investigate if collegiate hockey players could accurately perceive a change in body composition during a 3-month period within their regular season, in which no predetermined nutritional or exercise program was provided. Twenty-four male Canadian collegiate hockey players completed preseason and midseason body composition assessments using dual-energy X-ray absorptiometry. Immediately before the midseason scan, players attempted to accurately match their perceived fluctuation in composition, with predetermined categorical ranges of relative body composition and strength. Two-thirds of players and one-half of players accurately perceived changes in arm-lean and arm-fat tissue, respectively. Approximately two-thirds of players did not accurately perceive gains or losses of lean or fat tissue within their leg and overall body. Although some athletes partially detected changes in the lean and fat tissue of particular regions, the vast majority of players cannot detect the type, or amount of tissue gained and lost across the overall body. Body composition assessments, rather than an athlete's perceptions, should be used to help interpret the success of a sport nutrition or exercise program. Athletes should be aware that physiologic adaptations might take place unnoticed, which could affect the acceptance and adherence of nutrition or exercise interventions.

  20. The relation between perceived parent-created sport climate and competitive male youth hockey players' good and poor sport behaviors.

    PubMed

    LaVoi, Nicole M; Stellino, Megan Babkes

    2008-09-01

    The authors examined achievement goal orientation (J. L. Duda & J. G. Nicholls, 1992), parental influence (M. L. Babkes & M. R. Weiss, 1999), and the parent-initiated motivational climate (S. A. White, 1996, 1998) in combination to broaden understanding of competitive male youth hockey players' (N = 259) perceptions of the parent-created sport climate and its relation to their self-reported good and poor sport behaviors (GPSB). Exploratory factor analysis revealed a multidimensional measure of GPSB. Multiple regression analyses indicated that athletes' GPSB were significantly predicted by different forms of parental influence. Canonical correlations revealed a complex picture of the contributions of goal orientation and the parent-created sport climate on boys' GPSB in youth hockey. Results expand knowledge of the influence that parents have in youth sport and emphasize the importance of understanding how children's interpretations of parental beliefs and behaviors affect their choices to engage in good and poor sport behaviors.

  1. Tsunami Hockey

    NASA Astrophysics Data System (ADS)

    Weinstein, S.; Becker, N. C.; Wang, D.; Fryer, G. J.

    2013-12-01

    An important issue that vexes tsunami warning centers (TWCs) is when to cancel a tsunami warning once it is in effect. Emergency managers often face a variety of pressures to allow the public to resume their normal activities, but allowing coastal populations to return too quickly can put them at risk. A TWC must, therefore, exercise caution when cancelling a warning. Kim and Whitmore (2013) show that in many cases a TWC can use the decay of tsunami oscillations in a harbor to forecast when its amplitudes will fall to safe levels. This technique should prove reasonably robust for local tsunamis (those that are potentially dangerous within only 100 km of their source region) and for regional tsunamis (whose danger is limited to within 1000km of the source region) as well. For ocean-crossing destructive tsunamis such as the 11 March 2011 Tohoku tsunami, however, this technique may be inadequate. When a tsunami propagates across the ocean basin, it will encounter topographic obstacles such as seamount chains or coastlines, resulting in coherent reflections that can propagate great distances. When these reflections reach previously-impacted coastlines, they can recharge decaying tsunami oscillations and make them hazardous again. Warning center scientists should forecast sea-level records for 24 hours beyond the initial tsunami arrival in order to observe any potential reflections that may pose a hazard. Animations are a convenient way to visualize reflections and gain a broad geographic overview of their impacts. The Pacific Tsunami Warning Center has developed tools based on tsunami simulations using the RIFT tsunami forecast model. RIFT is a linear, parallelized numerical tsunami propagation model that runs very efficiently on a multi-CPU system (Wang et al, 2012). It can simulate 30-hours of tsunami wave propagation in the Pacific Ocean at 4 arc minute resolution in approximately 6 minutes of real time on a 12-CPU system. Constructing a 30-hour animation using 1 minute simulated time steps takes approximately 50 minutes on the same system. These animations are generated quickly enough to provide decision support for emergency managers whose coastlines may be impacted by the tsunami several hours later. Tsunami reflections can also aid in determining the source region for those tsunamis generated by non-seismic mechanisms without a clear source such as meteotsunamis, tsunamis generated by meteorological phenomena. A derecho that crossed the New Jersey coast and entered the Atlantic Ocean at approximately 1500 UTC June 13, 2013 generated a meteotsunami that struck the northeast coast of the US causing several injuries. A DART sensor off Montauk, NY, recorded tsunami waves approximately 200 minutes apart. We show how the arrival times of the tsunamis recorded by this DART can help to constrain the source region of the meteotsunami. We also examine other reflections produced by the Haida Gwaii 2012, Tohoku 2011, and other tsunamis.

  2. Off-ice fitness of elite female ice hockey players by team success, age, and player position.

    PubMed

    Ransdell, Lynda B; Murray, Teena M; Gao, Yong

    2013-04-01

    This study examined off-ice fitness profiles of 204 elite female ice hockey players from 13 countries who attended a high-performance camp organized by the International Ice Hockey Federation (IIHF) in Bratislava, Slovakia, in July of 2011. Athletes were tested using standardized protocols for vertical jump (centimeters), long jump (centimeters), 4-jump average (centimeters), elasticity ratio (4-vertical jump average/vertical jump), pull-up or inverted row (n), aerobic fitness (V[Combining Dot Above]O2max), body mass (kilograms), and body composition (% fat). These variables were examined relative to team success in major international hockey competition (group 1: Canada and USA, group 2: Sweden and Finland, group 3: All other participating countries), age group (Under 18 and Senior/Open Levels), and player position (forwards, defenders, and goalies). The athletes from countries with the best international records weighed more, yet had less body fat, had greater lower body muscular power and upper body strength, and higher aerobic capacity compared with their less successful counterparts. Compared with the younger athletes, athletes from the senior-level age group weighed more and had higher scores for lower body power, pull-ups, and aerobic capacity. There were no significant differences in anthropometric or fitness data based on player position. This study is the first to report the physical characteristics of a worldwide sample of elite female ice hockey players relative to team performance, age, and player position. Coaches should use these data to identify talent, test for strengths and weaknesses in conditioning programs, and design off-ice programs that will help athletes match the fitness profiles of the most successful teams in the world.

  3. Youth sports & public health: framing risks of mild traumatic brain injury in american football and ice hockey.

    PubMed

    Bachynski, Kathleen E; Goldberg, Daniel S

    2014-01-01

    The framing of the risks of experiencing mild traumatic brain injury in American football and ice hockey has an enormous impact in defining the scope of the problem and the remedies that are prioritized. According to the prevailing risk frame, an acceptable level of safety can be maintained in these contact sports through the application of technology, rule changes, and laws. An alternative frame acknowledging that these sports carry significant risks would produce very different ethical, political, and social debates.

  4. Pulmonary function decay in women ice hockey players: is there a relationship to ice rink air quality?

    PubMed

    Rundell, Kenneth W

    2004-03-01

    Fossil-fueled ice rink resurfacing machines emit high levels of ultrafine and fine particulate matter (PM(1)) and may be related to asthmalike symptoms in skaters. We examined PM(1) exposure and airway status in elite women ice hockey players over 4 training years. Lung function, asthma symptoms, and rink PM(1) were evaluated. Pre- and postexercise spirometry was performed on 14 female hockey players and 9 female control nordic skiers 4 times over 4 yr. Baseline lung functions were normalized to height cubed (Ht(3)) and recalculated to subject mean height (1.69 m) to evaluate change. Venue CO, NO(2), and PM(1) were measured. Training history for hockey players included 2 yr in a low-[PM(1)] rink, followed by transition to high-[PM(1)] fossil fuel machine resurfaced rinks; [PM(1)] for control ski venue was low. [CO] and [NO(2)] were acceptable at all venues. Controls showed no baseline function change over 4 yr. For hockey players, 1997 lung function values at the low-[PM(1)] venue were significantly higher than 2001 high-[PM(1)] venue values (p <.05); decay per year between 1997 and 2001 was greater for FEF(25-75) (251 +/- 185, 83 +/- 40, 109 +/- 58, 109 +/- 187 ml yr(-1), mean +/- SD for FEF(25-75), FVC, FEV1, PEF, respectively; p <.05). No relationships between baseline lung functions and airway hyperresponsiveness or symptoms were identified. Five of 9 controls had symptoms, and 10 of 14 subjects had symptoms. This preliminary study suggests [PM(1)] is related to airway function decay in ice rink athletes.

  5. Seasonal Changes in Whole Body and Regional Body Composition Profiles of Elite Collegiate Ice-Hockey Players.

    PubMed

    Prokop, Neal W; Reid, Ryan E R; Andersen, Ross E

    2016-03-01

    The monitoring of a collegiate hockey player's body composition can reflect fitness characteristics and may help players, coaches, or strength and conditioning specialists optimize physiologic gains during an off-season, whereas simultaneously preventing performance decrements in-season. The purpose of the study was to investigate changes in whole-body and regional-body composition of fat and lean tissue. The body composition profiles of 19 elite Canadian collegiate hockey players were assessed using dual energy X-ray absorptiometry. Players completed end-of-season, preseason, and midseason assessments with questionnaires relating to their off-season and in-season training. Statistically significant changes in body composition profiles were observed between the different time points because players showed various tissue gains and losses depending on the region assessed. Overall, players gained (1.38 kg, p ≤ 0.01) and lost (0.79 kg, p ≤ 0.01) fat tissue during the off-season and in-season, respectively. Players also showed a significant gain of leg lean tissue (0.29 kg, p = 0.02) and loss of arm tissue mass (-0.25 kg, p = 0.02) during the first-half of the competitive season. Several correlations emerged that may provide insight into potential trends that could be more pronounced during longer and more demanding schedules. Collegiate hockey players show changes in body composition during the off-season and in-season. The understanding of body composition profiles, body composition fluctuations, and potential variables that may influence the composition of collegiate hockey players can help coaches and athletic programs tailor their team's training, nutrition, lifestyle, and informative resources to further support their athletes.

  6. Can injury in major junior hockey players be predicted by a pre-season functional movement screen – a prospective cohort study

    PubMed Central

    Dossa, Khaled; Cashman, Glenn; Howitt, Scott; West, Bill; Murray, Nick

    2014-01-01

    Background: The Functional Movement Screen (FMS) is a tool that is commonly used to predict the occurrence of injury. Previous studies have shown that a score of 14 or less (with a maximum possible score of 21) successfully predicted future injury occurrence in athletes. No studies have looked at the use of the FMS to predict injuries in hockey players. Objective: To see if injury in major junior hockey players can be predicted by a preseason FMS. Methods: A convenience sample of 20 hockey players was scored on the FMS prior to the start of the hockey season. Injuries and number of man-games lost for each injury were documented over the course of the season. Results: The mean FMS score was 14.7+/−2.58. Those with an FMS score of ≤14 were not more likely to sustain an injury as determined by the Fisher’s exact test (one-tailed, P = 0.32). Conclusion: This study did not support the notion that lower FMS scores predict injury in major junior hockey players. PMID:25550667

  7. Physical fitness and performance of polish ice-hockey players competing at different sports levels

    PubMed Central

    Stanula, Arkadiusz; Gabryś, Tomasz; Szmatlan-Gabryś, Urszula; Gołaś, Artur; Stastny, Petr

    2016-01-01

    Abstract The study aimed to determine the values of selected aerobic and anaerobic capacity variables, physical profiles, and to analyze the results of on-ice tests performed by ice-hockey players relegated to a lower league. Performance of 24 ice-hockey players competing in the top league in the 2012/2013 season was analysed to this end. In the 2013/2014 season, 14 of them still played in the top league (the control group), while 10 played in the first league (the experimental group). The study was conducted one week after the end of the playoffs in the seasons under consideration. The results revealed that only in the experimental group the analysed variables changed significantly between the seasons. In the Wingate test, significant changes were only noted in mean relative power (a decrease from 9.91 to 9.14 W/kg; p=0.045) and relative total work (a decrease from 299.17 to 277.22 J/kg; p=0.048). The ramp test indicated significantly lower power output in its final stages (364 compared with 384 W; p=0.034), as well as a significant decrease in relative VO2max (from 52.70 to 48.30 ml/min/kg). Blood lactate concentrations were recorded at the 3rd, 6th, 9th and 12th min of recovery after the ramp test. The rate of post-exercise recovery, ∆LA, recorded after the ramp test turned out to be significantly lower. The times recorded in the on-ice “6x30 m stop” test increased from 32.18 to 33.10 s (p=0.047). The study showed that playing in a lower league where games were less intensive, training sessions shorter and less frequent, had an adverse effect on the performance level of the investigated players. Lower VO2max recorded in the study participants slowed down their rates of post-exercise recovery and led to a significantly worse performance in the 6x30 m stop test, as well as lower relative power and relative total work in the Wingate test. PMID:28149383

  8. Test-Retest Reliability of Computerized Neurocognitive Testing in Youth Ice Hockey Players.

    PubMed

    Womble, Melissa N; Reynolds, Erin; Schatz, Philip; Shah, Kishan M; Kontos, Anthony P

    2016-06-01

    Computerized neurocognitive tests are frequently used to assess pediatric sport-related concussions; however, only 1 study has focused on the test-retest reliability of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) in high school athletes and age influences have largely been ignored. Therefore, the purpose was to investigate the test-retest reliability of ImPACT and underlying age influences in a pediatric population. Two hundred (169 men and 31 women) youth ice hockey players completed ImPACT before/after a 6-month season. Reliability was assessed using Pearson correlation coefficients, intraclass correlation coefficients (ICCs), and regression-based methods (RBz). ICCs for the sample ranged from .48 to .75 (single)/.65 to .86 (average). In general, the older athletes (15-18: Single/Average ICCs = .35-.75/.52-.86) demonstrated greater reliability across composites than the younger athletes (11-14: Single/Average ICCs = .54-.63/.70-.77). Although there was variation in athletes' performance across two test administrations, RBz revealed that only a small percentage of athletes performed beyond 80%, 90%, and 95% confidence intervals. Statistical metrics demonstrated reliability coefficients for ImPACT composites in a pediatric sample similar to previous studies, and also revealed important age-related influences.

  9. Does fair play reduce concussions? A prospective, comparative analysis of competitive youth hockey tournaments

    PubMed Central

    Smith, Aynsley M; Gaz, Daniel V; Larson, Dirk; Jorgensen, Janelle K; Eickhoff, Chad; Krause, David A; Fenske, Brooke M; Aney, Katie; Hansen, Ashley A; Nanos, Stephanie M; Stuart, Michael J

    2016-01-01

    Background/aim To determine if Boys Bantam and Peewee and Girls U14 sustain fewer concussions, head hits, ‘other injuries’ and penalties in hockey tournaments governed by intensified fair play (IFP) than non-intensified fair play (NIFP). Methods A prospective comparison of IFP, a behaviour modification programme that promotes sportsmanship, versus control (non-intensified, NIFP) effects on numbers of diagnosed concussions, head hits without diagnosed concussion (HHWDC), ‘other injuries’, number of penalties and fair play points (FPPs). 1514 players, ages 11–14 years, in 6 IFP (N=950) and 5 NIFP (N=564) tournaments were studied. Results Two diagnosed concussions, four HHWDC, and six ‘other injuries’ occurred in IFP tournaments compared to one concussion, eight HHWDC and five ‘other injuries’ in NIFP. There were significantly fewer HHWDC in IFP than NIFP (p=0.018). However, diagnosed concussions, ‘other injuries’, penalties and FPPs did not differ significantly between conditions. In IFP, a minority of teams forfeited the majority of FPPs. Most diagnosed concussions, HHWDC, and other injuries occurred to Bantam B players and usually in penalised teams that forfeited their FPPs. Conclusions In response to significant differences in HHWDC between IFP and NIFP tournaments, the following considerations are encouraged: mandatory implementation of fair play in regular season and tournaments, empowering tournament directors to not accept heavily penalised teams, and introducing ‘no body checking’ in Bantam. PMID:27900157

  10. Upper-limb kinematics and coordination of short grip and classic drives in field hockey.

    PubMed

    Bretigny, Perrine; Seifert, Ludovic; Leory, David; Chollet, Didier

    2008-08-01

    The aim of this study was to compare the upper-limb kinematics and coordination of the short grip and classic drives in field hockey. Ten elite female players participated in the experiment. The VICON system was used to record the displacement of markers placed on the stick and the players' joints during five short grip and five classic drives. Kinematic and coordination parameters were analyzed. The ball's velocity was recorded by a radar device that also served as the drive target. Kinematic differences were noted between the two drive conditions, with shorter duration and smaller overall amplitude in the short grip drive, explained by the shorter lever arm and the specific context in which it is used. No differences were noted for upper-limb coordination. In both types of stick holding, an interlimb dissociation was noted on the left side, whereas the right interlimb coordination was in phase. Moreover, the time lag increased in the disto-proximal direction, suggesting wrist uncocking before impact and the initiation of descent motion by the left shoulder. Mediolateral analysis confirmed these results: coordination of left-right limbs converged at the wrist but dissociated with more proximal joints (elbows and shoulders).

  11. Defining the effective impact mass of elbow and shoulder strikes in ice hockey.

    PubMed

    Rousseau, Philippe; Hoshizaki, Thomas B

    2015-03-01

    Reconstruction of real-life events can be used to investigate the relationship between the mechanical parameters of the impact and concussion risk. Striking mass has typically been approximated as being the mass of the body part coming into contact with the head without accounting for the force applied by the striking athlete. Thus, the purpose of this study was to measure the effective impact mass of three common striking techniques in ice hockey. Fifteen participants were instructed to strike a suspended 50th percentile Hybrid III headform at least three times with their elbow or shoulder. Effective impact mass was calculated by measuring the change in velocity of the player and the headform. Mean effective impact mass for the extended elbow, tucked-in elbow, and shoulder check conditions were 4.8, 3.0, and 12.9 kg, respectively. Peak linear accelerations were lower than the values associated with concussion in American football which could be a reflection of the methodology used in this study as well as inherent differences between both sports.

  12. Relationship between body composition, leg strength, anaerobic power, and on-ice skating performance in division I men's hockey athletes.

    PubMed

    Potteiger, Jeffrey A; Smith, Dean L; Maier, Mark L; Foster, Timothy S

    2010-07-01

    The purpose of this study was to examine relationships between laboratory tests and on-ice skating performance in division I men's hockey athletes. Twenty-one men (age 20.7 +/- 1.6 years) were assessed for body composition, isokinetic force production in the quadriceps and hamstring muscles, and anaerobic muscle power via the Wingate 30-second cycle ergometer test. Air displacement plethysmography was used to determine % body fat (%FAT), fat-free mass (FFM), and fat mass. Peak torque and total work during 10 maximal effort repetitions at 120 degrees .s were measured during concentric muscle actions using an isokinetic dynamometer. Muscle power was measured using a Monark cycle ergometer with resistance set at 7.5% of body mass. On-ice skating performance was measured during 6 timed 89-m sprints with subjects wearing full hockey equipment. First length skate (FLS) was 54 m, and total length skate (TLS) was 89 m with fastest and average skating times used in the analysis. Correlation coefficients were used to determine relationships between laboratory testing and on-ice performance. Subjects had a body mass of 88.8 +/- 7.8 kg and %FAT of 11.9 +/- 4.6. First length skate-Average and TLS-Average skating times were moderately correlated to %FAT ([r = 0.53; p = 0.013] and [r = 0.57; p = 0.007]) such that a greater %FAT was related to slower skating speeds. First length skate-Fastest was correlated to Wingate percent fatigue index (r = -0.48; p = 0.027) and FLS-Average was correlated to Wingate peak power per kilogram body mass (r = -0.43; p = 0.05). Laboratory testing of select variables can predict skating performance in ice hockey athletes. This information can be used to develop targeted and effective strength and conditioning programs that will improve on-ice skating speed.

  13. Influence of Cognitive Interferences and Self-Talk Functions on Performance During Competition in Elite Female Field Hockey Players.

    PubMed

    Pérez-Encinas, Cristina; Fernández-Campos, Francisco J; Rodas, Gil; Barrios, Carlos

    2016-12-01

    Pérez-Encinas, C, Fernández-Campos, FJ, Rodas, G, and Barrios, C. Influence of cognitive interferences and self-talk functions on performance during competition in elite female field hockey players. J Strength Cond Res 30(12): 3339-3346, 2016-Cognitive interferences in the form of distracting thoughts and self-talk functions may play an important role in athletes' performance. The purpose of this study was to explore the types of interfering thoughts and the concomitant use of self-talk functions occurring in a sample of elite female field hockey players. The variation in these interferences in relation to athletes' performance level in competition was also investigated. Thirty-two female players of the first and the Under-21 National Team completed the Thought Occurrence Questionnaire for Sport and the Self-Talk Questionnaire after an international competition. The trainer rated the players' performance during competition in 3 different categories according to his expectancies based on the athletes' conditioning: Low (n = 6), Normal (n = 15), and High Performance (n = 11). Those players classified as low performing had increased the occurrence of irrelevant thoughts as compared with other groups. These athletes also showed the highest scores on the thoughts of escape subscale. Athletes with high performance during tournaments exhibited the lowest scores on all subscales, especially in thoughts of escape. The S-TQ subscales showed no differences among the 3 performance groups. Under-21 players had higher scores on the occurrence of performance worries and thoughts of escape subscales than first national team players. Interfering thoughts are common in female field hockey players during world-class competitions. The occurrence of irrelevant thoughts and thoughts of escape was related to players exhibiting low performance. The use of self-talk functions was relatively low in these athletes and could explain the enhanced occurrence of interfering thoughts.

  14. Ability of Preseason Body Composition and Physical Fitness to Predict the Risk of Injury in Male Collegiate Hockey Players

    PubMed Central

    Grant, John A.; Bedi, Asheesh; Kurz, Jennifer; Bancroft, Richard; Gagnier, Joel J.; Miller, Bruce S.

    2015-01-01

    Background: Injuries in collegiate ice hockey can result in significant time lost from play. The identification of modifiable risk factors relating to a player’s physical fitness allows the development of focused training and injury prevention programs targeted at reducing these risks. Purpose: To determine the ability of preseason fitness outcomes to predict in-season on-ice injury in male collegiate ice hockey players. Study Design: Prognostic cohort study. Level of Evidence: Level 3. Methods: Athlete demographics, percentage body fat, aerobic capacity (300-m shuttle run; 1-, 1.5-, 5-mile run), and strength assessment (sit-ups, push-ups, grip strength, bench press, Olympic cleans, squats) data were collected at the beginning of 8 successive seasons for 1 male collegiate ice hockey team. Hockey-related injury data and player-level practice/game athlete exposure (AE) data were also prospectively collected. Seventy-nine players participated (203 player-years). Injury was defined as any event that resulted in the athlete being unable to participate in 1 or more practices or games following the event. Multivariable logistic regression was performed to determine the ability of the independent variables to predict the occurrence of on-ice injury. Results: There were 132 injuries (mean, 16.5 per year) in 55 athletes. The overall injury rate was 4.4 injuries per 1000 AEs. Forwards suffered 68% of the injuries. Seventy percent of injuries occurred during games with equal distribution between the 3 periods. The mean number of days lost due to injury was 7.8 ± 13.8 (range, 1-127 days). The most common mechanism of injury was contact with another player (54%). The odds of injury in a forward was 1.9 times (95% CI, 1.1-3.4) that of a defenseman and 3 times (95% CI, 1.2-7.7) that of a goalie. The odds of injury if the player’s body mass index (BMI) was ≥25 kg/m2 was 2.1 times (95% CI, 1.1-3.8) that of a player with a BMI <25 kg/m2. The odds ratios for bench press

  15. Muscle Oxygen Changes following Sprint Interval Cycling Training in Elite Field Hockey Players

    PubMed Central

    Jones, Ben; Hamilton, David K.; Cooper, Chris E.

    2015-01-01

    This study examined the effects of Sprint Interval Cycling (SIT) on muscle oxygenation kinetics and performance during the 30-15 intermittent fitness test (IFT). Twenty-five women hockey players of Olympic standard were randomly selected into an experimental group (EXP) and a control group (CON). The EXP group performed six additional SIT sessions over six weeks in addition to their normal training program. To explore the potential training-induced change, EXP subjects additionally completed 5 x 30s maximal intensity cycle testing before and after training. During these tests near-infrared spectroscopy (NIRS) measured parameters; oxyhaemoglobin + oxymyoglobin (HbO2+ MbO2), tissue deoxyhaemoglobin + deoxymyoglobin (HHb+HMb), total tissue haemoglobin (tHb) and tissue oxygenation (TSI %) were taken. In the EXP group (5.34±0.14 to 5.50±0.14m.s-1) but not the CON group (pre = 5.37±0.27 to 5.39±0.30m.s-1) significant changes were seen in the 30-15IFT performance. EXP group also displayed significant post-training increases during the sprint cycling: ΔTSI (−7.59±0.91 to −12.16±2.70%); ΔHHb+HMb (35.68±6.67 to 69.44±26.48μM.cm); and ΔHbO2+ MbO2 (−74.29±13.82 to −109.36±22.61μM.cm). No significant differences were seen in ΔtHb (−45.81±15.23 to −42.93±16.24). NIRS is able to detect positive peripheral muscle oxygenation changes when used during a SIT protocol which has been shown to be an effective training modality within elite athletes. PMID:25807517

  16. Effects of a diet regimen on pituitary and steroid hormones in male ice hockey players.

    PubMed

    Tegelman, R; Aberg, T; Pousette, A; Carlström, K

    1992-07-01

    Serum concentrations of androgens, cortisol, androgen binding proteins, pituitary hormones, together with anthropometric variables and sports performance were studied in two different elite male ice hockey teams. One of the teams (DIF, n = 22) participated in a special dietary program including reduction in fat from approximately 40 per cent of total energy intake (E%) to less than 30 E% and an increase in carbohydrate intake from 45 E% to about 55 E%, while the other (SSK, n = 21) served as a control group and had no special dietary program. The study covered a 7-month period. Basal values of serum testosterone, sex hormone binding globulin (SHBG), non-SHBG-bound testosterone (NST), cortisol, dehydroepiandrosterone sulfate (DHAS) and LH did not differ between the two teams. Serum concentrations of testosterone, SHBG, NST and cortisol increased significantly during the study period in the DIF group and were, with the exception of SHBG, significantly higher than in the SSK group at the end of the study (33.0 vs 26.8 nmol/l, p less than 0.05; 22.5 vs 18.3 nmol/l, p less than 0.05; and 548 vs 464 nmol/l, p less than 0.01). The ratio between NST and cortisol which was used as an index of anabolic/catabolic steroid balance did not change in either group during the study. A significant decrease in the serum concentrations of LH during the observation period was found in the SSK group. The endocrine differences between the teams may be explained by a relative negative energy balance in DIF, together with a reduced fat and increased carbohydrate intake.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Head impact exposure in male and female collegiate ice hockey players.

    PubMed

    Wilcox, Bethany J; Beckwith, Jonathan G; Greenwald, Richard M; Chu, Jeffrey J; McAllister, Thomas W; Flashman, Laura A; Maerlender, Arthur C; Duhaime, Ann-Christine; Crisco, Joseph J

    2014-01-03

    The purpose of this study was to quantify head impact exposure (frequency, location and magnitude of head impacts) for individual male and female collegiate ice hockey players and to investigate differences in exposure by sex, player position, session type, and team. Ninety-nine (41 male, 58 female) players were enrolled and 37,411 impacts were recorded over three seasons. Frequency of impacts varied significantly by sex (males: 287 per season, females: 170, p<0.001) and helmet impact location (p<0.001), but not by player position (p=0.088). Head impact frequency also varied by session type; both male and female players sustained more impacts in games than in practices (p<0.001), however the magnitude of impacts did not differ between session types. There was no difference in 95th percentile peak linear acceleration between sexes (males: 41.6 g, females: 40.8 g), but 95th percentile peak rotational acceleration and HITsp (a composite severity measure) were greater for males than females (4424, 3409 rad/s(2), and 25.6, 22.3, respectively). Impacts to the back of the helmet resulted in the greatest 95th percentile peak linear accelerations for males (45.2 g) and females (50.4 g), while impacts to the side and back of the head were associated with the greatest 95th percentile peak rotational accelerations (males: 4719, 4256 rad/sec(2), females: 3567, 3784 rad/sec(2) respectively). It has been proposed that reducing an individual's head impact exposure is a practical approach for reducing the risk of brain injuries. Strategies to decrease an individual athlete's exposure need to be sport and gender specific, with considerations for team and session type.

  18. Physiological responses to repeated apneas in underwater hockey players and controls.

    PubMed

    Lemaître, F; Polin, D; Joulia, F; Boutry, A; Le Pessot, D; Chollet, D; Tourny-Chollet, C

    2007-01-01

    The aim of this study was to investigate the effects of short repeated apneas on breathing pattern and circulatory response in trained (underwater hockey players: UHP) and untrained (controls: CTL) subjects. The subjects performed five apneas (A1-A5) while cycling with the face immersed in thermoneutral water. Respiratory parameters were recorded 1 minute before and after each apnea and venous blood samples were collected before each apnea and at 0, 2, 5 and 10 minutes after the last apnea. Arterial saturation (SaO2) and heart rate were continuously recorded during the experiment. Before the repeated apneas, UHP had lower ventilation, higher P(ET)CO2 (p < 0.05) and lower P(ET)O2 than CTL (p < 0.001). After the apneas, the P(ET)O2 values were always lower in UHP (p < 0.001) than CTL but with no difference for averaged P(ET)CO2 (p = 0.32). The apnea response, i.e., bradycardia and increased mean arterial blood pressure, was observed and it remained unchanged throughout the series in the two groups. The SaO, decreased in both groups during each apnea but the post-exercise SaO2 values were higher in UHP after A2 to A5 than in CTL (p < 0.01). The post-apnea lactate concentrations were lower in UHP than in CTL. These results indicate that more pronounced bradycardia could lead to less oxygen desaturation during repeated apneas in UHP. The UHP show a specific hypoventilatory pattern after repeated apneas, as well as a more pronounced cardiovascular response than CTL. They indeed showed no detraining of the diving response.

  19. Locomotor, Heart-Rate, and Metabolic Power Characteristics of Youth Women's Field Hockey: Female Athletes in Motion (FAiM) Study

    ERIC Educational Resources Information Center

    Vescovi, Jason D.

    2016-01-01

    Purpose: The purpose of this study was to quantify the locomotor, heart-rate, and metabolic power characteristics of high-level youth female field hockey matches. Method: Players from the U21 and U17 Canadian women's national teams were monitored during a 4-match test series using Global Positioning System technology. Position (forward,…

  20. Using Elite Athletes to Promote Drug Abstinence: Evaluation of a Single-Session School-Based Drug Use Prevention Program Delivered by Junior Hockey Players

    ERIC Educational Resources Information Center

    Wong, Jennifer

    2016-01-01

    School-based substance use prevention programs are a common method to approaching drug use in youths. Project SOS is a single-session drug prevention program developed by police officers and delivered by elite junior hockey players to students in grades 6 and 7. The current study evaluates the effects of Project SOS at achieving its objectives of…

  1. Analysis of international competition and training in men's field hockey by global positioning system and inertial sensor technology.

    PubMed

    White, Andrew D; MacFarlane, Niall G

    2015-01-01

    This study assessed the relative demands of elite field hockey training and competition to determine whether familiar exercise prescription strategies provide an appropriate training stimulus. Sixteen elite male field hockey players (age, 25 ± 4 years; body mass, 70.9 ± 6.6 kg; and maximal oxygen consumption, 61.0 ± 2.1 ml·kg·min [mean ± SD]) participated in the study. Seventy-five elite level competition and 37 training analyses from 8 games and 4 training sessions were obtained. Training duration was longer than competition and covered a greater total distance (109 ± 2.5 vs. 74 ± 0.3 minutes and 7318 ± 221 vs. 5868 ± 75 m; p < 0.001 in both). The distance covered sprinting and running at high intensity was not different between training and competition (114 ± 6 vs. 116 ± 9 m when sprinting and 457 ± 6 vs. 448 ± 7 m for high-intensity running). More high-intensity accelerations were performed during training than in competition (37 ± 3 vs. 20 ± 2). Despite having lower predicted aerobic capacity and covering less distance in competition than in some previous studies, these data support the suggestion that it is high-intensity activity that differentiates international level competition and further suggests that international players can replicate the intensity of competition during small-sided games.

  2. Validity of a 5-meter multiple shuttle run test for assessing fitness of women field hockey players.

    PubMed

    Boddington, Michele K; Lambert, Michael I; Waldeck, Miriam R

    2004-02-01

    The aim of this study was to establish validity of a 5-m multiple shuttle test (5-m MST) using indirect (criterion and construct) and direct measures of performance. For criterion validity, comparisons were made between data from established fitness tests and a 5-m MST. Construct validity was determined by comparing results from a 5-m MST with subjects of different playing abilities. Direct validity was determined by comparing values attained from a 5-m MST with data from a time-motion study of field hockey. For criterion validity, the strongest relationship existed between the 20-m MST (42.7 +/- 7.1 ml.kg(-1).min(-1)) and total distance from the 5-m MST (650.9 +/- 59.2 m; r = 0.92). For construct validity, regional representative players covered more distance than club-level players (689.9 +/- 46.6 m vs. 661.1 +/- 31.0 m; p < 0.01). For direct validity, the highest correlation was found between total distance from the 5-m MST (706.0 +/- 37.5 m) and mean displacement during matches (61.0 +/- 6.0 m; r = 0.74). It was concluded that the 5-m MST had both indirect and direct validity for the fitness assessment of field hockey players. The data obtained from the 5-m MST directly relates to the physical fitness of the players during competition.

  3. Temperature dependences of the electrooptical properties of rodlike nematic liquid crystals doped with hockey-stick-shaped liquid crystals

    NASA Astrophysics Data System (ADS)

    Yeo, Sunggu; Srivastava, Anoop Kumar; Lee, Hyojin; Lee, Ji-Hoon; Choi, E.-Joon

    2016-01-01

    We investigated the temperature dependences of the dielectric anisotropy, birefringence, order parameter, splay elastic constant, and rotational viscosity of rodlike nematic liquid crystals (RLCs) doped with hockey-stick-shaped liquid crystals (HLCs). Although the order parameter of the HLC-RLC mixtures was similar to that of the pure RLC, the dielectric anisotropy and the birefringence of the mixtures were decreased or increased depending on the structure of the HLC molecule. In addition, the activation energies of the mixtures were different, which implies that the intramolecular structure of the HLC molecule had more influence on the electrooptical properties of the HLC-RLC binary mixtures than the inter-molecular interaction between the HLC and the RLC molecules.

  4. The ability of parents to accurately report concussion occurrence in their bantam-aged minor hockey league children

    PubMed Central

    Coghlin, Craig J; Myles, Bryan D; Howitt, Scott D.

    2009-01-01

    Objective: The objective of this study was to assess the ability of hockey parents/guardians to recognize concussion symptoms in their 13–14 year old (Bantam-aged) children. Outcome Measures: The outcome measures were the ability to recognize different signs and symptoms listed on the Sport Concussion Assessment Tool (SCAT) as well as 8 detractors consisting of signs and symptoms not associated with post concussive syndrome. Additional questions assessing the parents’ knowledge of concussion management and recognition abilities were also posed. Participants: Parents of Bantam-aged minor hockey league athletes volunteered for the study. Methods: The study investigators distributed questionnaires during the warm up period or following their children’s games to the study participants. Following questionnaire completion, participants were provided with an information package outlining the correct signs and symptoms of concussion. Results: The mean number of correct responses to signs and symptoms of concussion was 21.25/25 for the mothers and 20.41/25 for the fathers. The mean number of detractors identified as not associated with concussion was 5.93/8 for the mothers and 4.85/8 for the fathers, indicating that mothers were more capable of recognizing the signs and symptoms than fathers. An analysis of variance including sporting experience in the model did not strengthen the relationship between parent gender and test outcome. Conclusion: This investigation revealed that there is still a disconnect in regards to key components of recognizing a concussion, such as difficulty with sleep, disorientation symptoms, and emotional irritability. Mothers have displayed an ability to better differentiate between true and false signs and symptoms of concussion as compared to fathers. Continued education and awareness of mild traumatic brain injury in athletes should address the misconceptions amongst parents in regards to the true signs and symptoms of a concussion. PMID

  5. Skin conditions in figure skaters, ice-hockey players and speed skaters: part I - mechanical dermatoses.

    PubMed

    Tlougan, Brook E; Mancini, Anthony J; Mandell, Jenny A; Cohen, David E; Sanchez, Miguel R

    2011-09-01

    Figure skaters, ice-hockey players and speed skaters experience a range of dermatologic conditions and tissue-related injuries on account of mechanical trauma, infectious pathogens, inflammatory processes and environmental factors related to these competitive pursuits. Sports medicine practitioners, family physicians, dermatologists and coaches should be familiar with these skin conditions to ensure timely and accurate diagnosis and management of affected athletes. This review is Part I of a subsequent companion review and provides a comprehensive review of mechanical dermatoses experienced by ice-skating athletes, including skater's nodules and its variants, pump bumps, piezogenic pedal papules, talon noir, skate/lace bite, friction bullae, corns and calluses, onychocryptosis, skater's toe and skate blade-induced lacerations. These injuries result from friction, shear forces, chronic pressure and collisions with surfaces that occur when athletes endure repetitive jump landings, accelerated starts and stops and other manoeuvres during rigorous training and competition. Ill-fitting skates, improper lacing techniques and insufficient lubrication or protective padding of the foot and ankle often contribute to the development of skin conditions that result from these physical and mechanical stresses. As we will explain, simple measures can frequently prevent the development of these conditions. The treatment of skater's nodules involves reduction in chronic stimulation of the malleoli, and the use of keratolytics and intralesional steroid injections; if malleolar bursitis develops, bursa aspirations may be required. Pump bumps, which result from repetitive friction posteriorly, can be prevented by wearing skates that fit correctly at the heel. Piezogenic pedal papules may be treated conservatively by using heel cups, compressive stockings and by reducing prolonged standing. Talon noir usually resolves without intervention within several weeks. The treatment of skate

  6. Multinational outbreak of Salmonella Enteritidis infection during an international youth ice hockey competition in Riga, Latvia, preliminary report, March and April 2015.

    PubMed

    Pesola, A K; Parn, T; Huusko, S; Perevosčikovs, J; Ollgren, J; Salmenlinna, S; Lienemann, T; Gossner, C; Danielsson, N; Rimhanen-Finne, R

    2015-05-21

    A multinational outbreak of salmonellosis linked to the Riga Cup 2015 junior ice-hockey competition was detected by the Finnish health authorities in mid-April and immediately notified at the European Union level. This prompted an international outbreak investigation supported by the European Centre for Disease Prevention and Control. As of 8 May 2015, seven countries have reported 214 confirmed and suspected cases, among which 122 from Finland. The search for the source of the outbreak is ongoing.

  7. Multidisciplinary approach to non-surgical management of inguinal disruption in a professional hockey player treated with platelet-rich plasma, manual therapy and exercise: a case report

    PubMed Central

    St-Onge, Eric; MacIntyre, Ian G.; Galea, Anthony M.

    2015-01-01

    Objective: To present the clinical management of inguinal disruption in a professional hockey player and highlight the importance of a multidisciplinary approach to diagnosis and management. Clinical Features: A professional hockey player with recurrent groin pain presented to the clinic after an acute exacerbation of pain while playing hockey. Intervention: The patient received a clinical diagnosis of inguinal disruption. Imaging revealed a tear in the rectus abdominis. Management included two platelet-rich plasma (PRP) injections to the injured tissue, and subsequent manual therapy and exercise. The patient returned to his prior level of performance in 3.5 weeks. Discussion: This case demonstrated the importance of a multidisciplinary team and the need for advanced imaging in athletes with groin pain. Summary: Research quality concerning the non-surgical management of inguinal disruption remains low. This case adds evidence that PRP, with the addition of manual therapy and exercise may serve as a relatively quick and effective non-surgical management strategy. PMID:26816415

  8. The role of visual perception measures used in sports vision programmes in predicting actual game performance in Division I collegiate hockey players.

    PubMed

    Poltavski, Dmitri; Biberdorf, David

    2015-01-01

    Abstract In the growing field of sports vision little is still known about unique attributes of visual processing in ice hockey and what role visual processing plays in the overall athlete's performance. In the present study we evaluated whether visual, perceptual and cognitive/motor variables collected using the Nike SPARQ Sensory Training Station have significant relevance to the real game statistics of 38 Division I collegiate male and female hockey players. The results demonstrated that 69% of variance in the goals made by forwards in 2011-2013 could be predicted by their faster reaction time to a visual stimulus, better visual memory, better visual discrimination and a faster ability to shift focus between near and far objects. Approximately 33% of variance in game points was significantly related to better discrimination among competing visual stimuli. In addition, reaction time to a visual stimulus as well as stereoptic quickness significantly accounted for 24% of variance in the mean duration of the player's penalty time. This is one of the first studies to show that some of the visual skills that state-of-the-art generalised sports vision programmes are purported to target may indeed be important for hockey players' actual performance on the ice.

  9. Laboratory- and field-based testing as predictors of skating performance in competitive-level female ice hockey

    PubMed Central

    Henriksson, Tommy; Vescovi, Jason D; Fjellman-Wiklund, Anncristine; Gilenstam, Kajsa

    2016-01-01

    Objectives The purpose of this study was to examine whether field-based and/or laboratory-based assessments are valid tools for predicting key performance characteristics of skating in competitive-level female hockey players. Design Cross-sectional study. Methods Twenty-three female ice hockey players aged 15–25 years (body mass: 66.1±6.3 kg; height: 169.5±5.5 cm), with 10.6±3.2 years playing experience volunteered to participate in the study. The field-based assessments included 20 m sprint, squat jump, countermovement jump, 30-second repeated jump test, standing long jump, single-leg standing long jump, 20 m shuttle run test, isometric leg pull, one-repetition maximum bench press, and one-repetition maximum squats. The laboratory-based assessments included body composition (dual energy X-ray absorptiometry), maximal aerobic power, and isokinetic strength (Biodex). The on-ice tests included agility cornering s-turn, cone agility skate, transition agility skate, and modified repeat skate sprint. Data were analyzed using stepwise multivariate linear regression analysis. Linear regression analysis was used to establish the relationship between key performance characteristics of skating and the predictor variables. Results Regression models (adj R2) for the on-ice variables ranged from 0.244 to 0.663 for the field-based assessments and from 0.136 to 0.420 for the laboratory-based assessments. Single-leg tests were the strongest predictors for key performance characteristics of skating. Single leg standing long jump alone explained 57.1%, 38.1%, and 29.1% of the variance in skating time during transition agility skate, agility cornering s-turn, and modified repeat skate sprint, respectively. Isokinetic peak torque in the quadriceps at 90° explained 42.0% and 32.2% of the variance in skating time during agility cornering s-turn and modified repeat skate sprint, respectively. Conclusion Field-based assessments, particularly single-leg tests, are an adequate

  10. Exploitation of a “hockey-puck” phenotype to identify pilus and biofilm regulators in Serratia marcescens through genetic analysis

    PubMed Central

    Shanks, Robert M.Q.; Stella, Nicholas A.; Brothers, Kimberly M.; Polaski, Denise M.

    2016-01-01

    Pili are essential adhesive determinants for many bacterial pathogens. A suppressor mutation screen that takes advantage of a pilus-mediated self-aggregative “hockey-puck” colony phenotype was designed to identify novel regulators of type I pili in Serratia marcescens. Mutations that decreased pilus biosynthesis mapped to the fimABCD operon; to the genes alaT, fkpA, and oxyR; upstream of the flagellar master regulator operon flhDC; and to an uncharacterized gene encoding a predicted DUF1401 domain. biofilm formation and pilus-dependent agglutination assays were used to characterize the relative importance of the identified genes in pilus biosynthesis. Additional mutagenic or complementation analysis was used to verify the role of candidate genes in pilus biosynthesis. Presented data support a model that CRP negatively regulates pilus biosynthesis through increased expression of flhDC and decreased expression of oxyR. Further studies are warranted to determine the mechanism by which these genes mediate pilus biosynthesis or function. PMID:26640000

  11. The prevalence of musculoskeletal pain and use of painkillers among adolescent male ice hockey players in Finland.

    PubMed

    Selanne, Harri; Ryba, Tatiana V; Siekkinen, Kirsti; Kyröläinen, Heikki; Kautiainen, Hannu; Hakonen, Harto; Mikkelsson, Marja; Kujala, Urho M

    2014-01-01

    Participating in competitive sport increases the risk for injuries and musculoskeletal pain among adolescent athletes. There is also evidence that the use of prescription drugs has increased among sport club athletes. The purpose of this study was to evaluate the use of painkillers among young male ice hockey players (IHP) in comparison to schoolboys (controls) and its relation to the prevalence of musculoskeletal pain and problems during activities and sleeping. Information was gathered through a questionnaire, completed by 121 IHP and compared to the responses of 618 age-matched controls. Results showed that monthly existing pain was at 82% for IHP, and 72% for controls, though IHP had statistically more musculoskeletal pain in their lower limbs (56% vs. 44%), lower back (54% vs. 35%), and buttocks (26% vs. 11%). There were no group differences in the neck, upper back, upper limb, or chest areas. The disability index was statistically similar for both groups, as musculoskeletal pain causing difficulties in daily activities and sleeping was reported by a minority of subjects. Despite this similarity, IHP used more painkillers than controls (18% vs. 10%). Further nuanced research is encouraged to compare athletes and non-athletes in relation to painkillers.

  12. A simple video-based timing system for on-ice team testing in ice hockey: a technical report.

    PubMed

    Larson, David P; Noonan, Benjamin C

    2014-09-01

    The purpose of this study was to describe and evaluate a newly developed on-ice timing system for team evaluation in the sport of ice hockey. We hypothesized that this new, simple, inexpensive, timing system would prove to be highly accurate and reliable. Six adult subjects (age 30.4 ± 6.2 years) performed on ice tests of acceleration and conditioning. The performance times of the subjects were recorded using a handheld stopwatch, photocell, and high-speed (240 frames per second) video. These results were then compared to allow for accuracy calculations of the stopwatch and video as compared with filtered photocell timing that was used as the "gold standard." Accuracy was evaluated using maximal differences, typical error/coefficient of variation (CV), and intraclass correlation coefficients (ICCs) between the timing methods. The reliability of the video method was evaluated using the same variables in a test-retest analysis both within and between evaluators. The video timing method proved to be both highly accurate (ICC: 0.96-0.99 and CV: 0.1-0.6% as compared with the photocell method) and reliable (ICC and CV within and between evaluators: 0.99 and 0.08%, respectively). This video-based timing method provides a very rapid means of collecting a high volume of very accurate and reliable on-ice measures of skating speed and conditioning, and can easily be adapted to other testing surfaces and parameters.

  13. Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts.

    PubMed

    Richards, Darrin; Ivarsson, B Johan; Scher, Irving; Hoover, Ryan; Rodowicz, Kathleen; Cripton, Peter

    2016-11-01

    Ice hockey body checks involving direct shoulder-to-head contact frequently result in head injury. In the current study, we examined the effect of shoulder pad style on the likelihood of head injury from a shoulder-to-head check. Shoulder-to-head body checks were simulated by swinging a modified Hybrid-III anthropomorphic test device (ATD) with and without shoulder pads into a stationary Hybrid-III ATD at 21 km/h. Tests were conducted with three different styles of shoulder pads (traditional, integrated and tethered) and without shoulder pads for the purpose of control. Head response kinematics for the stationary ATD were measured. Compared to the case of no shoulder pads, the three different pad styles significantly (p < 0.05) reduced peak resultant linear head accelerations of the stationary ATD by 35-56%. The integrated shoulder pads reduced linear head accelerations by an additional 18-21% beyond the other two styles of shoulder pads. The data presented here suggest that shoulder pads can be designed to help protect the head of the struck player in a shoulder-to-head check.

  14. Sediment quality thresholds: Estimates from hockey stick regression of liver lesion prevalence in English sole (Pleuronectes vetulus)

    SciTech Connect

    Horness, B.H.; Lomax, D.P.; Johnson, L.L.; Myers, M.S.; Pierce, S.M.; Collier, T.K.

    1998-01-01

    Comprehensive, integrative assessments of coastal sediment quality are best effected by using large, diverse data sets that include measures of biological dysfunction observed in association with chronic exposure to sediment contaminants. Under the auspices of the National Oceanic and Atmospheric Administration`s National Status and Trends Program, the National Benthic Surveillance Project accumulated a database of synoptic sediment contaminant concentrations and indices of biological effects that were measured in indigenous animals collected during field surveys conducted from 1984 to 1994. This compilation of data provided the opportunity to develop a new approach for determining sediment quality criteria to add to the current repertoire of environmental assessment tools. Using a two-segment hockey stick regression, statistically significant chemical thresholds of biological effects were estimated for hepatic lesion prevalences in English sole (Pleuronectes vetulus, formerly Parophrys vetulus) in relation to sediment concentrations of polycyclic aromatic hydrocarbons. These threshold estimates are notably lower than many of those reported for other techniques. Application of this relatively simple dose-response model to subacute, chronic effects that are involved in pepatocarcinogenesis and associated with sediment toxicant content (1) reflects the link between toxicopathic disease progression and conditions observed in benthic fish exposed to contaminants and (2) provides endpoints for assessing sediment quality contaminant concentrations that are not necessarily acutely fatal but may have long-term health implications for populations that are chronically exposed.

  15. Dosimetry of a single ''hockey stick'' portal for treatment of tumors of the cranio-spinal axis

    SciTech Connect

    Glasgow, G.P.; Marks, J.E.

    1983-09-01

    Conventional treatment of tumors of the cranio-spinal axis portal usually involves multiple-field, moving junction treatments to avoid overlapping fields over the spinal cord. To avoid these problems, we irradiate the cranio-spinal axis using a single ''hockey stick'' portal and the 25-MV x-ray beam from a Varian Clinac-35/sup X/ linear accelerator. Patients are positioned prone on the floor 229 cm from the radiation source and the collimators are rotated 45/sup 0/ so the maximum diagonal dimension of the field 116 cm at 229 cm is coincident with the cranio-spinal axis. The head is alternately rotated to treat the right-hand side one day and the left-hand side the next day. Thermoluminescent dosimetry in an anatomical phantom reveals that, relative to the 100% dose delivered at 4-cm depth on the central axis of the blocked field, the midline posterior fossa dose is about 100%, with a maximum dose of about 105% to the extreme posterior portion of the skull. The midline neck dose is about 95% and the dose to the inferior portion of the spinal cord is about 105%. The doses to other critical organs are also presented.

  16. NON-SURGICAL TREATMENT OF A PROFESSIONAL HOCKEY PLAYER WITH THE SIGNS AND SYMPTOMS OF SPORTS HERNIA: A CASE REPORT

    PubMed Central

    Woodward, J. Scott; Parker, Andrew; MacDonald, Robert M.

    2012-01-01

    Study Design: Case Report Background: Injury or weakness of lower abdominal attachments and the posterior inguinal wall can be symptoms of a “sports hernia” and an underlying source of groin pain. Although several authors note conservative treatment as the initial step in the management of this condition, very little has been written on the specific description of non-surgical measures. Most published articles favoring operative care describe poor results related to conservative management; however they fail to report what treatment techniques comprise non-operative management. Case Presentation: The subject of this case report is a professional ice hockey player who sustained an abdominal injury in a game, which was diagnosed as a sports hernia. Following the injury, structured conservative treatment emphasized core control and stability with progressive peripheral demand challenges. Intrinsic core control emphasis continued throughout the treatment progression and during the functional training prior to return to sport. Outcome: The player completed his recovery with return to full competition seven weeks post injury, and continues to compete in the NHL seven years later. Discussion: Surgical intervention has been shown to be effective in the treatment of the “sports hernia.” However it is the authors' opinion that conservative care emphasizing evaluation of intrinsic core muscular deficits and rehabilitation directed at addressing these deficits is an appropriate option, and should be considered prior to surgical intervention. PMID:22319682

  17. Perfectionism and achievement goals in young Finnish ice-hockey players aspiring to make the Under-16 national team.

    PubMed

    Stoeber, Joachim; Stoll, Oliver; Salmi, Olli; Tiikkaja, Jukka

    2009-01-01

    Research on perfectionism suggests that is it useful to differentiate between perfectionistic strivings and perfectionistic concerns. Regarding the 2x2 achievement goal framework, the usefulness of this differentiation was recently demonstrated in a study with university student athletes (Stoeber, Stoll, Pescheck, & Otto, 2008, Study 2), in which it was found that perfectionistic strivings were associated with mastery-approach and performance-approach goals and perfectionistic concerns with mastery-avoidance, performance-approach, and performance-avoidance goals. Because the study was largely exploratory and only used non-elite athletes, the aim of the present research was to replicate and extend these findings by investigating a sample of 138 young, elite ice-hockey players, while adding further measures of perfectionism and using structural equation modelling (SEM) to confirm the relationships between perfectionistic strivings, perfectionistic concerns, and the 2x2 achievement goals. The SEM results showed that, in elite athletes also, perfectionistic strivings are associated with mastery-approach and performance-approach goals, whereas perfectionistic concerns are associated with mastery-avoidance, performance-approach, and performance-avoidance goals. Our findings corroborate the importance of differentiating between perfectionistic strivings and perfectionistic concerns when studying perfectionism in sports, because only perfectionistic concerns (and not perfectionistic strivings) are associated with maladaptive patterns of achievement goals.

  18. Sweat rate, salt loss, and fluid intake during an intense on-ice practice in elite Canadian male junior hockey players.

    PubMed

    Palmer, Matthew S; Spriet, Lawrence L

    2008-04-01

    Previous research in many sports suggests that losing ~1%-2% body mass through sweating impairs athletic performance. Elite-level hockey involves high-intensity bursts of skating, arena temperatures are >10 degrees C, and players wear protective equipment, all of which promote sweating. This study examined the pre-practice hydration, on-ice fluid intake, and sweat and sodium losses of 44 candidates for Canada's junior men's hockey team (mean +/- SE age, 18.4 +/- 0.1 y; height, 184.8 +/- 0.9 cm; mass, 89.9 +/- 1.1 kg). Players were studied in groups of 10-12 during 4 intense 1 h practices (13.9 degrees C, 66% relative humidity) on 1 day. Hydration status was estimated by measuring urine specific gravity (USG). Sweat rate was calculated from body mass changes and fluid intake. Sweat sodium concentration ([Na]) was analyzed in forehead sweat patch samples and used with sweat rate to estimate sodium loss. Over 50% of players began practice mildly hypohydrated (USG > 1.020). Sweat rate during practice was 1.8 +/- 0.1 L.h(-1) and players replaced 58% (1.0 +/- 0.1 L.h(-1)) of the sweat lost. Body mass loss averaged 0.8% +/- 0.1%, but 1/3 of players lost more than 1%. Sweat [Na] was 54.2 +/- 2.4 mmol.L(-1) and sodium loss averaged 2.26 +/- 0.17 g during practice. Players drank only water during practice and replaced no sodium. In summary, elite junior hockey players incurred large sweat and sodium losses during an intense practice, but 2/3 of players drank enough to minimize body mass loss. However, 1/3 of players lost more than 1% body mass despite ready access to fluid and numerous drinking opportunities from the coaches.

  19. On-ice sweat rate, voluntary fluid intake, and sodium balance during practice in male junior ice hockey players drinking water or a carbohydrate-electrolyte solution.

    PubMed

    Palmer, Matthew S; Logan, Heather M; Spriet, Lawrence L

    2010-06-01

    This study evaluated the repeatability of hydration and sweat measurements taken during on-ice hockey practices with players drinking only water, and determined whether having only a carbohydrate-electrolyte solution (CES) to drink during practices decreased fluid intake or affected other hydration and (or) sweat measures. All testing was conducted on elite players of an Ontario Hockey League team (+/-SE; mean age, 17.6 +/- 0.3 years; mean height, 182.9 +/- 1.4 cm; mean body mass, 83.0 +/- 1.7 kg). Players were studied 3 times over the course of 6 weekly on-ice practices (+/-SE; mean playing time, 1.58 +/- 0.07 h; mean temperature, 11.4 +/- 0.8 degrees C; mean relative humidity, 52% +/- 3%). There was strong repeatability of the measured hydration and sweat parameters between 2 similar on-ice practices when players drank only water. Limiting the players to drinking only a CES (as opposed to water) did not decrease fluid intake during practice (+/-SE; mean CES intake, 0.72 +/- 0.07 L.h-1 vs. mean water intake, 0.82 +/- 0.08 L.h-1) or affect sweat rate (1.5 +/- 0.1 L.h-1 vs. 1.5 +/- 0.1 L.h-1), sweat sodium concentration (72.4 +/- 5.6 mmol.L-1 vs. 73.0 +/- 4.4 mmol.L-1), or percent body mass loss (1.1% +/- 0.2% vs. 0.9% +/- 0.2%). Drinking a CES also improved sodium balance (-2.1 +/- 0.2 g.h-1 vs. -2.6 +/- 0.3 g.h-1) and provided the players with a significant carbohydrate (43 +/- 4 g.h-1 vs. 0 +/- 0 g.h-1) during practice. In summary, a single field sweat test during similar on-ice hockey practices in male junior hockey players is sufficient to evaluate fluid and electrolyte balance. Also, a CES does not affect voluntary fluid intake during practice, compared with water, in these players. The CES provided some salt to offset the salt lost in sweat, and carbohydrate, which may help maintain physical and mental performance in the later stages of practice.

  20. Effect of hockey-stick-shaped molecules on the critical behavior at the nematic to isotropic and smectic-A to nematic phase transitions in octylcyanobiphenyl

    NASA Astrophysics Data System (ADS)

    Chakraborty, Anish; Chakraborty, Susanta; Das, Malay Kumar

    2015-03-01

    In the field of soft matter research, the characteristic behavior of both nematic-isotropic (N -I ) and smectic-A nematic (Sm -A N ) phase transitions has gained considerable attention due to their several attractive features. In this work, a high-resolution measurement of optical birefringence (Δ n ) has been performed to probe the critical behavior at the N -I and Sm -A N phase transitions in a binary system comprising the rodlike octylcyanobiphenyl and a laterally methyl substituted hockey-stick-shaped mesogen, 4-(3-n -decyloxy-2-methyl-phenyliminomethyl)phenyl 4-n -dodecyloxycinnamate. For the investigated mixtures, the critical exponent β related to the limiting behavior of the nematic order parameter close to the N -I phase transition has come out to be in good conformity with the tricritical hypothesis. Moreover, the yielded effective critical exponents (α', β', γ') characterizing the critical fluctuation near the Sm -A N phase transition have appeared to be nonuniversal in nature. With increasing hockey-stick-shaped dopant concentration, the Sm -A N phase transition demonstrates a strong tendency to be driven towards a first-order nature. Such a behavior has been accounted for by considering a modification of the effective intermolecular interactions and hence the related coupling between the nematic and smectic order parameters, caused by the introduction of the angular mesogenic molecules.

  1. Reliability, usefulness, and validity of the 30-15 Intermittent Ice Test in young elite ice hockey players.

    PubMed

    Buchheit, Martin; Lefebvre, Benjamin; Laursen, Paul B; Ahmaidi, Said

    2011-05-01

    The purpose of this study was to examine the reliability, usefulness, and validity of the 30-15 Intermittent Ice Test (30-15(IIT)) in 17 young elite ice hockey players. For the reliability and usefulness study, players performed the 30-15(IIT) 7 days apart. For the validity study, data derived from the first 30-15(IIT) were compared with those obtained from the 30-15 Intermittent Fitness Test (30-15(IFT), the running version of this test used as a reference marker for its ability to assess cardiovascular fitness in the field, that is, VO₂peak). Maximal speed, heart rate at exhaustion (HR(peak)) and postexercise blood-lactate levels ([La](b)) were collected for all tests, whereas submaximal HR was taken at stages 4 and 8 (HR(stage4) and HR(stage8)) during the 30-15(IIT). All intra-class correlation coefficients were >0.94. Coefficients of variation were 1.6% (90% CI, 1.3-2.3), 1.7% (1.3-2.8), 1.4% (1.0-2.2), and 0.7% (0.5-1.1) for maximal skating speed, HR(stage4), HR(stage8), and HR(peak), respectively. Correlations between maximal velocities and HR(peak) obtained for the 30-15(IIT) vs. 30-15(IFT) were very large (r = 0.72) and large (r = 0.61), respectively. Maximal skating speed was also largely correlated to estimated VO₂peak (r = 0.71). There was however no correlation for [La](b) values between both tests (r = 0.42). These results highlight the specificity of the on-ice 30-15(IIT) and show it to be a reliable and valid test for assessing cardiorespiratory fitness in young elite players. Coaches could interpret a change in performance of at least 2 stages, or a change in submaximal HR of more than 8% (≈8 b·min⁻¹) during the eighth stage to be a meaningful change in skating fitness.

  2. Multiple Off-Ice Performance Variables Predict On-Ice Skating Performance in Male and Female Division III Ice Hockey Players.

    PubMed

    Janot, Jeffrey M; Beltz, Nicholas M; Dalleck, Lance D

    2015-09-01

    The purpose of this study was to determine if off-ice performance variables could predict on-ice skating performance in Division III collegiate hockey players. Both men (n = 15) and women (n = 11) hockey players (age = 20.5 ± 1.4 years) participated in the study. The skating tests were agility cornering S-turn, 6.10 m acceleration, 44.80 m speed, modified repeat skate, and 15.20 m full speed. Off-ice variables assessed were years of playing experience, height, weight and percent body fat and off-ice performance variables included vertical jump (VJ), 40-yd dash (36.58m), 1-RM squat, pro-agility, Wingate peak power and peak power percentage drop (% drop), and 1.5 mile (2.4km) run. Results indicated that 40-yd dash (36.58m), VJ, 1.5 mile (2.4km) run, and % drop were significant predictors of skating performance for repeat skate (slowest, fastest, and average time) and 44.80 m speed time, respectively. Four predictive equations were derived from multiple regression analyses: 1) slowest repeat skate time = 2.362 + (1.68 x 40-yd dash time) + (0.005 x 1.5 mile run), 2) fastest repeat skate time = 9.762 - (0.089 x VJ) - (0.998 x 40-yd dash time), 3) average repeat skate time = 7.770 + (1.041 x 40-yd dash time) - (0.63 x VJ) + (0.003 x 1.5 mile time), and 4) 47.85 m speed test = 7.707 - (0.050 x VJ) - (0.01 x % drop). It was concluded that selected off-ice tests could be used to predict on-ice performance regarding speed and recovery ability in Division III male and female hockey players. Key pointsThe 40-yd dash (36.58m) and vertical jump tests are significant predictors of on-ice skating performance specific to speed.In addition to 40-yd dash and vertical jump, the 1.5 mile (2.4km) run for time and percent power drop from the Wingate anaerobic power test were also significant predictors of skating performance that incorporates the aspect of recovery from skating activity.Due to the specificity of selected off-ice variables as predictors of on-ice performance, coaches can

  3. Multiple Off-Ice Performance Variables Predict On-Ice Skating Performance in Male and Female Division III Ice Hockey Players

    PubMed Central

    Janot, Jeffrey M.; Beltz, Nicholas M.; Dalleck, Lance D.

    2015-01-01

    The purpose of this study was to determine if off-ice performance variables could predict on-ice skating performance in Division III collegiate hockey players. Both men (n = 15) and women (n = 11) hockey players (age = 20.5 ± 1.4 years) participated in the study. The skating tests were agility cornering S-turn, 6.10 m acceleration, 44.80 m speed, modified repeat skate, and 15.20 m full speed. Off-ice variables assessed were years of playing experience, height, weight and percent body fat and off-ice performance variables included vertical jump (VJ), 40-yd dash (36.58m), 1-RM squat, pro-agility, Wingate peak power and peak power percentage drop (% drop), and 1.5 mile (2.4km) run. Results indicated that 40-yd dash (36.58m), VJ, 1.5 mile (2.4km) run, and % drop were significant predictors of skating performance for repeat skate (slowest, fastest, and average time) and 44.80 m speed time, respectively. Four predictive equations were derived from multiple regression analyses: 1) slowest repeat skate time = 2.362 + (1.68 x 40-yd dash time) + (0.005 x 1.5 mile run), 2) fastest repeat skate time = 9.762 - (0.089 x VJ) - (0.998 x 40-yd dash time), 3) average repeat skate time = 7.770 + (1.041 x 40-yd dash time) - (0.63 x VJ) + (0.003 x 1.5 mile time), and 4) 47.85 m speed test = 7.707 - (0.050 x VJ) - (0.01 x % drop). It was concluded that selected off-ice tests could be used to predict on-ice performance regarding speed and recovery ability in Division III male and female hockey players. Key points The 40-yd dash (36.58m) and vertical jump tests are significant predictors of on-ice skating performance specific to speed. In addition to 40-yd dash and vertical jump, the 1.5 mile (2.4km) run for time and percent power drop from the Wingate anaerobic power test were also significant predictors of skating performance that incorporates the aspect of recovery from skating activity. Due to the specificity of selected off-ice variables as predictors of on-ice performance, coaches

  4. Determination of nicotine and nicotine metabolites in urine by hydrophilic interaction chromatography-tandem mass spectrometry: Potential use of smokeless tobacco products by ice hockey players.

    PubMed

    Marclay, François; Saugy, Martial

    2010-11-26

    Consumption of nicotine in the form of smokeless tobacco (snus, snuff, chewing tobacco) or nicotine-containing medication (gum, patch) may benefit sport practice. Indeed, use of snus seems to be a growing trend and investigating nicotine consumption amongst professional athletes is of major interest to sport authorities. Thus, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the detection and quantification of nicotine and its principal metabolites cotinine, trans-3-hydroxycotinine, nicotine-N'-oxide and cotinine-N-oxide in urine was developed. Sample preparation was performed by liquid-liquid extraction followed by hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS) operated in electrospray positive ionization (ESI) mode with selective reaction monitoring (SRM) data acquisition. The method was validated and calibration curves were linear over the selected concentration ranges of 10-10,000 ng/mL for nicotine, cotinine, trans-3-hydroxycotinine and 10-5000 ng/mL for nicotine-N'-oxide and cotinine-N-oxide, with calculated coefficients of determination (R(2)) greater than 0.95. The total extraction efficiency (%) was concentration dependent and ranged between 70.4 and 100.4%. The lower limit of quantification (LLOQ) for all analytes was 10 ng/mL. Repeatability and intermediate precision were ≤9.4 and ≤9.9%, respectively. In order to measure the prevalence of nicotine exposure during the 2009 Ice Hockey World Championships, 72 samples were collected and analyzed after the minimum of 3 months storage period and complete removal of identification means as required by the 2009 International Standards for Laboratories (ISL). Nicotine and/or metabolites were detected in every urine sample, while concentration measurements indicated an exposure within the last 3 days for eight specimens out of ten. Concentrations of nicotine, cotinine, trans-3-hydroxycotinine, nicotine-N'-oxide and cotinine-N-oxide were found to range

  5. Myelin Water Fraction Is Transiently Reduced after a Single Mild Traumatic Brain Injury – A Prospective Cohort Study in Collegiate Hockey Players

    PubMed Central

    Vavasour, Irene; Shahinfard, Elham; Kolind, Shannon; van Donkelaar, Paul; Taunton, Jack; Li, David; Rauscher, Alexander

    2016-01-01

    Impact-related mild traumatic brain injuries (mTBI) are a major public health concern, and remain as one of the most poorly understood injuries in the field of neuroscience. Currently, the diagnosis and management of such injuries are based largely on patient-reported symptoms. An improved understanding of the underlying pathophysiology of mTBI is urgently needed in order to develop better diagnostic and management protocols. Specifically, dynamic post-injury changes to the myelin sheath in the human brain have not been examined, despite ‘compromised white matter integrity’ often being described as a consequence of mTBI. In this preliminary cohort study, myelin water imaging was used to prospectively evaluate changes in myelin water fraction, derived from the T2 decay signal, in two varsity hockey teams (45 players) over one season of athletic competition. 11 players sustained a concussion during competition, and were scanned at 72 hours, 2 weeks, and 2 months post-injury. Results demonstrated a reduction in myelin water fraction at 2 weeks post-injury in several brain areas relative to preseason scans, including the splenium of the corpus callosum, right posterior thalamic radiation, left superior corona radiata, left superior longitudinal fasciculus, and left posterior limb of the internal capsule. Myelin water fraction recovered to pre-season values by 2 months post-injury. These results may indicate transient myelin disruption following a single mTBI, with subsequent remyelination of affected neurons. Myelin disruption was not apparent in the athletes who did not experience a concussion, despite exposure to repetitive subconcussive trauma over a season of collegiate hockey. These findings may help to explain many of the metabolic and neurological deficits observed clinically following mTBI. PMID:26913900

  6. Gender Difference in Aerobic Capacity and the Contribution by Body Composition and Haemoglobin Concentration: A Study in Young Indian National Hockey Players

    PubMed Central

    Kailashiya, Jyotsna

    2016-01-01

    Introduction Although gender difference in aerobic capacity is known, the contributing factors have been researched seldom. Aim To investigate the gender gap and the contribution by percentage Body Fat (BF), Body Mass Index (BMI) and haemoglobin concentration Hb. Materials and Methods The study was conducted on 30 (17 males, 13 females) training status matched young hockey players. Healthy players who were playing upto national level competition were included. BW (Body Weight), BF, BMI, LBM (Lean Body Mass), rHR (restring Heart Rate), HRR (Heart Rate Recovery), Hb, a/rVO2max (absolute/relative), a/rPWC (Physical Work Capacity) and RMR (Resting Metabolic Rate) were measured and analysed. Results There was significant gender difference in the measured parameters. Difference in a/rVO2max remained significant even after controlling for BF, BMI and Hb. Multiple regression and correlation analysis revealed gender difference in VO2max/LBM was due to: BMI(31.91%)>BF(27.60%)>Hb(9.91%). BMI also significantly contributed 3.66% of VO2max/LBM variance, independent of that by gender. Difference in RMR was mainly related to LBM, BF and BMI. Conclusion The study provided an understanding for gender gap in aerobic capacity. Differences in BMI & BF were one of the main reasons. PMID:28050360

  7. Campus Computing Looks Ahead: Tracking the Digital Puck.

    ERIC Educational Resources Information Center

    Green, Kenneth C.

    2002-01-01

    Examines data from the 2002 Campus Computing Survey to determine trends in information technology in higher education and future possibilities. Discusses Web portals; electronic commerce capabilities, including use of credit cards; budget challenges, including budget cuts; and mobile technology and wireless networks. (LRW)

  8. Who Has the Puck? Strategic Initiative in Modern, Conventional War

    DTIC Science & Technology

    2009-08-01

    20pacific/ww2%20pacific%20%20maps/ ww2%20asia%20map% 2017 .jpg, accessed 16 April 2008). THE PACIFIC WAR, 1941–45 73 During the second phase, the United...April 1945 “skillfully utilized terrain to inflict maxi - mum casualties” that totaled 49,451 men, of which 12,520 were dead or missing, although

  9. Skin conditions in figure skaters, ice-hockey players and speed skaters: part II - cold-induced, infectious and inflammatory dermatoses.

    PubMed

    Tlougan, Brook E; Mancini, Anthony J; Mandell, Jenny A; Cohen, David E; Sanchez, Miguel R

    2011-11-01

    Participation in ice-skating sports, particularly figure skating, ice hockey and speed skating, has increased in recent years. Competitive athletes in these sports experience a range of dermatological injuries related to mechanical factors: exposure to cold temperatures, infectious agents and inflammation. Part I of this two part review discussed the mechanical dermatoses affecting ice-skating athletes that result from friction, pressure, and chronic irritation related to athletic equipment and contact with surfaces. Here, in Part II, we review the cold-induced, infectious and inflammatory skin conditions observed in ice-skating athletes. Cold-induced dermatoses experienced by ice-skating athletes result from specific physiological effects of cold exposure on the skin. These conditions include physiological livedo reticularis, chilblains (pernio), Raynaud phenomenon, cold panniculitis, frostnip and frostbite. Frostbite, that is the literal freezing of tissue, occurs with specific symptoms that progress in a stepwise fashion, starting with frostnip. Treatment involves gradual forms of rewarming and the use of friction massages and pain medications as needed. Calcium channel blockers, including nifedipine, are the mainstay of pharmacological therapy for the major nonfreezing cold-induced dermatoses including chilblains and Raynaud phenomenon. Raynaud phenomenon, a vasculopathy involving recurrent vasospasm of the fingers and toes in response to cold, is especially common in figure skaters. Protective clothing and insulation, avoidance of smoking and vasoconstrictive medications, maintaining a dry environment around the skin, cold avoidance when possible as well as certain physical manoeuvres that promote vasodilation are useful preventative measures. Infectious conditions most often seen in ice-skating athletes include tinea pedis, onychomycosis, pitted keratolysis, warts and folliculitis. Awareness, prompt treatment and the use of preventative measures are

  10. The Incidence and Types of Physical Contact Associated with Body Checking Regulation Experience in 13–14 Year Old Ice Hockey Players

    PubMed Central

    Goulet, Claude; Roy, Thierry-Olivier; Nadeau, Luc; Hamel, Denis; Fortier, Kristine; Emery, Carolyn A.

    2016-01-01

    Background: Ice hockey has one of the highest sport participation and injury rates in youth in Canada. Body checking (BC) is the predominant mechanism of injury in leagues in which it is permitted. The objectives of this study were to determine whether the incidence and types of physical contact differ for Bantam players (aged 13–14 years) who were exposed to BC at Pee Wee level (aged 11–12 years) in Calgary, Alberta versus Bantam players who were not exposed to BC at Pee Wee level in Québec City, Québec. All teams were exposed to BC at bantam level; Methods: A cohort study was conducted in Québec City and Calgary. Sixteen games for Calgary and 15 for Québec City were randomly selected and analysed with a validated observation system to quantify five intensities of physical contact and to observe different types of physical contact such as slashing and holding; Results: A total of 5610 incidences of physical contact with the trunk and 3429 other types of physical contact were observed. Very light intensity trunk contact was more frequent in Calgary (adjusted incidence RR (ARR): 1.71; 95% CI: 1.28–2.29). Holding (ARR: 1.04; 95% CI: 1.02–1.07) and slashing (ARR: 1.38; 95% CI: 1.07–1.77) were more frequent in Calgary; Conclusion: Results suggest that players’ physical contacts differ between Bantam leagues in which BC was permitted at Pee Wee level and leagues in which it was not permitted until Bantam level. PMID:27399750

  11. Effects of Neuromuscular Training on the Rear-foot Angle Kinematics in Elite Women Field Hockey Players with Chronic Ankle Instability

    PubMed Central

    Kim, Eunkuk; Choi, Hokyung; Cha, Jung-Hoon; Park, Jong-Chul; Kim, Taegyu

    2017-01-01

    The aims of this study were to investigate the ankle position, the changes and persistence of ankle kinematics after neuromuscular training in athletes with chronic ankle instability (CAI). A total of 21 national women’s field hockey players participated (CAI = 12, control = 9). Ankle position at heel strike (HS), midstance (MS), and toe touch (TT) in the frontal plane during walking, running and landing were measured using 3D motion analysis. A 6-week neuromuscular training program was undertaken by the CAI group. Measurements of kinematic data for both groups were measured at baseline and the changes in kinematic data for CAI group were measured at 6 and 24 weeks. The kinematic data at HS during walking and running demonstrated that the magnitude of the eversion in the CAI group (−5.00° and −4.21°) was less than in the control group (−13.45°and −9.62°). The kinematic data at MS also exhibited less ankle eversion in the CAI group (−9.36° and −8.18°) than in the control group (−18.52° and −15.88°). Ankle positions at TT during landing were comparable between groups. Following the 6-week training, the CAI participants demonstrated a less everted ankle at HS during walking and running (−1.77° and −1.76°) compared to the previous positions. They also showed less ankle eversion at MS (−5.14° and −4.19°). Ankle orientation at TT changed significantly to an inverted ankle position (from −0.26° to 4.11°). The ankle kinematics were restored back to the previous positions at 24 weeks except for landing. It appeared that athletes with unstable ankle had a relatively inverted ankle position, and that 6-week neuromuscular training had an immediate effect on changing ankle orientation toward a less everted direction. The changed ankle kinematics seemed to persist during landing but not during walking and running. Key points Athletes with unstable ankles had a relatively inverted ankle position during the initial contact and midstance

  12. Myositis ossificans traumatica of the deltoid ligament in a 34 year old recreational ice hockey player with a 15 year post-trauma follow-up: a case report and review of the literature

    PubMed Central

    Muir, Brad

    2010-01-01

    Myositis ossificans traumatica is a relatively common injury associated with sports especially those involving contact. It continues to frustrate both athlete and health practitioner alike due to its continued lack of treatment options and a lengthy natural history. This case study chronicles the observation of a 34 year old recreational ice hockey player who presented 7 years post-trauma, was diagnosed with myositis ossificans traumatica and was followed up on 8 years later (15 years post-trauma). This case report is suspected to be the first published case study of its kind. The literature review outlines the various types of myositis ossificans, its incidence, pathogenesis, differential diagnoses including osteosarcoma, and the various methods/modalities reported in its treatment. PMID:21120014

  13. Potpourri: Hollywood, History, and Hockey.

    ERIC Educational Resources Information Center

    Kelebay, Yarema Gregory

    1992-01-01

    Offers thoughts on criticisms directed against conservatives, the deline of Montreal's commercial activity, and the deaths of economist F. A. Hayek, author Roger Lemelin, and journalist Barbara Frum. Briefly examines the irony of teaching sex education while downplaying religious instruction. Explores the decline of Quebec's culture and…

  14. Particle-hole intruder levels in 67Cu, collectivity, monopole shifts, and the hockey-stick behaviour of ell - 1/2 5/2- levels in neutron-rich odd-mass Cu nuclei

    NASA Astrophysics Data System (ADS)

    Walters, W. B.; Chiara, C. J.

    2011-01-01

    A new sequence of gamma rays with energies of 572, 499, 585, and 674 keV has been identified in 67Cu populating the 7/2- level at 2362 keV. Owing to the strong population of the 2362-keV level via an ell = 3 proton pickup reaction, that level is assigned to be an f7/2-1 2-particle-1-hole "intruder" proton configuration, and the new levels are found to form a sequence consistent with intruder sequences in the adjacent odd-mass Cu isotopes and in the odd-mass Sb isotopes. The changing position of the intruder sequence in the odd-mass Cu isotopes is discussed and related to the onset of collectivity associated with the presence of g9/2 neutrons beyond N = 40. The increase in collectivity is also discussed for a number of isotonic and isotopic chains as more protons or neutrons, respectively, are added beyond an oscillator shell boundary. For most of these systems, the ell -1/2 levels show a systematic "hockey-stick-like" behaviour with a sharp decrease in energy with the addition of the first protons or neutrons, owing to both the added collectivity and the tensor interaction, and then a lower slope when collectivity changes are diminished and only the tensor interaction is influencing the changes in level positions.

  15. 'Biracial'-Looking Twins: A New Twin Type?/Twin Research: Twins with Cystic Teratomas; Sleep Quality and Body Mass Index; Previable Membrane Rupture/Print and Online Reports: Twins Born to a Sister Surrogate; NASA Twin Study; African-Cosmopolitan Twin Fashion Inspirations; Triplet Hockey Stars.

    PubMed

    Segal, Nancy L

    2017-03-28

    Dizygotic (DZ) co-twins born to mothers and fathers from different racial or ethnic backgrounds often resemble one parent much more than the other. As such, these pairs comprise a unique subset of twins for investigating how others' responses to their different looks may affect their personalities and self-esteem. This article describes some of these twin pairs and some challenges of raising them, and suggests ways they may be used in research. Next, recent twin research on cystic teratomas, relations between sleep quality and body mass index, and previable membrane rupture is described. The final section concerns twins, twin studies, and related events in the media, namely: twins born to a sister surrogate, the NASA twin investigation, inspiring African-Cosmopolitan twins in fashion, and triplet Hockey Stars.

  16. Puck in the Schoolyard: Crassing the Bard at Hawthorn Secondary College.

    ERIC Educational Resources Information Center

    Hayes, Terry

    1999-01-01

    Claims doing "A Midsummer Night's Dream" as a school production allows students to bring their own personalities and cultures into the play. Explains how the production can be both inclusive, making room for many extra actions, as well communal, vivifying a school community to make it live more intensely. (NH)

  17. A Cool Sport Full of Physics

    NASA Astrophysics Data System (ADS)

    Haché, Alain

    2008-10-01

    Of all sports, ice hockey is possibly the one with the widest array of physics elements in it. The game provides many examples that can bring physics to life in the classroom. Ice hockey (or just "hockey" as many Canadians would say) sees athletes sliding on ice at high speeds and in various ways, shooting and slapping pucks, and colliding against each other. The interaction between the skate blade and the ice is a problem of great physical complexity. The question "Why is ice so slippery?" has puzzled generations of scientists and, surprisingly, clear answers have come relatively recently. There is even some optics involved in hockey: how many sports are watched behind tempered glass (or Plexiglas) windows? The optical and mechanical properties of these materials are worth a physics classroom discussion. In this paper, I will review a few topics discussed at length in my book The Physics of Hockey.1,2 Interested readers may also find additional articles on our website.3

  18. Ojibway Hockey CD ROM in the Making.

    ERIC Educational Resources Information Center

    Williams, Shirley I.

    A shortage of instructional materials and activities is a continual problem for Native language courses, as is making the material relevant to students. The Native way of teaching and learning has always been to have fun. In response to these concerns, a group of language experts at Trent University (Ontario) are developing a CD-ROM for high…

  19. Using action observation to study superior motor performance: a pilot fMRI study

    PubMed Central

    Olsson, Carl-Johan; Lundström, Peter

    2013-01-01

    The most efficient way to acquire motor skills may be through physical practice. Nevertheless, it has also been shown that action observation may improve motor performance. The aim of the present pilot study was to examine a potential action observation paradigm used to (1) capture the superior performance of expert athletes and (2) capture the underlying neural mechanisms of successful action observation in relation to task experience. We used functional magnetic resonance imaging to measure regional blood flow while presenting videos of a hockey player shooting a puck toward a hockey goal. The videos (a total of 120) where stopped at different time frames with different amount of information provided, creating a paradigm with three different levels of difficulty to decide the fate of a shot. Since this was only a pilot study, we first tested the paradigm behaviorally on six elite expert hockey players, five intermediate players, and six non-hockey playing controls. The results showed that expert hockey players were significantly (p < 0.05) more accurate on deciding the fate of the action compared to the others. Thus, it appears as if the paradigm can capture superior performance of expert athletes (aim 1). We then tested three of the hockey players and three of the controls on the same paradigm in the MRI scanner to investigate the underlying neural mechanisms of successful action anticipation. The imaging results showed that when expert hockey players observed and correctly anticipated situations, they recruited motor and temporal regions of the brain. Novices, on the other hand, relied on visual regions during observation and prefrontal regions during action decision. Thus, the results from the imaging data suggest that different networks of the brain are recruited depending on task experience (aim 2). In conclusion, depending on the level of motor skill of the observer, when correctly anticipating actions different neural systems will be recruited. PMID

  20. The Limits of Spacepower

    DTIC Science & Technology

    2007-11-02

    used at geosynchronous orbit, where only so many parking spots for satellites are available. Experiments with a low-earth orbiting information system...jammer the size of a hockey puck costing only $500 can radiate 1W of power, making it effective up to a range of 70km. 42 Russia has for sale a 4W...capability.𔃾 9 It would complicate your adversary’s attack plan by giving him more targets to shoot at. But before you shoot , you must first locate

  1. Augmented Reality Comes to Physics

    NASA Astrophysics Data System (ADS)

    Buesing, Mark; Cook, Michael

    2013-04-01

    Augmented reality (AR) is a technology used on computing devices where processor-generated graphics are rendered over real objects to enhance the sensory experience in real time. In other words, what you are really seeing is augmented by the computer. Many AR games already exist for systems such as Kinect and Nintendo 3DS and mobile apps, such as Tagwhat and Star Chart (a must for astronomy class). The yellow line marking first downs in a televised football game2 and the enhanced puck that makes televised hockey easier to follow3 both use augmented reality to do the job.

  2. Ultra-Compact Motor Controller

    NASA Technical Reports Server (NTRS)

    Townsend, William T.; Cromwell, Adam; Hauptman, Traveler; Pratt, Gill Andrews

    2012-01-01

    This invention is an electronically commutated brushless motor contro ller that incorporates Hall-array sensing in a small, 42-gram packag e that provides 4096 absolute counts per motor revolution position s ensing. The unit is the size of a miniature hockey puck, and is a 44 -pin male connector that provides many I/O channels, including CANbus , RS-232 communications, general-purpose analog and digital I/O (GPI O), analog and digital Hall inputs, DC power input (18-90 VDC, 0-l0 A), three-phase motor outputs, and a strain gauge amplifier.

  3. The “Puck” energetic charged particle detector: Design, heritage, and advancements

    PubMed Central

    Cohen, I.; Westlake, J. H.; Andrews, G. B.; Brandt, P.; Gold, R. E.; Gkioulidou, M. A.; Hacala, R.; Haggerty, D.; Hill, M. E.; Ho, G. C.; Jaskulek, S. E.; Kollmann, P.; Mauk, B. H.; McNutt, R. L.; Mitchell, D. G.; Nelson, K. S.; Paranicas, C.; Paschalidis, N.; Schlemm, C. E.

    2016-01-01

    Abstract Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low‐resource missions in the past, the need was recognized for a low‐resource but highly capable, mass‐species‐discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the “Puck” EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high‐voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions. PMID:27867799

  4. Pilot study to test effectiveness of video game on reaching performance in stroke.

    PubMed

    Acosta, Ana Maria; Dewald, Hendrik A; Dewald, Jules P A

    2011-01-01

    Robotic systems currently used in upper-limb rehabilitation following stroke rely on some form of visual feedback as part of the intervention program. We evaluated the effect of a video game environment (air hockey) on reaching in stroke with various levels of arm support. We used the Arm Coordination Training 3D system to provide variable arm support and to control the hockey stick. We instructed seven subjects to reach to one of three targets covering the workspace of the impaired arm during the reaching task and to reach as far as possible while playing the video game. The results from this study showed that across subjects, support levels, and targets, the reaching distances achieved with the reaching task were greater than those covered with the video game. This held even after further restricting the mapped workspace of the arm to the area most affected by the flexion synergy (effectively forcing subjects to fight the synergy to reach the hockey puck). The results from this study highlight the importance of designing video games that include specific reaching targets in the workspace compromised by the expression of the flexion synergy. Such video games would also adapt the target location online as a subject's success rate increases.

  5. Video Gaming Promotes Concussion Knowledge Acquisition in Youth Hockey Players

    ERIC Educational Resources Information Center

    Goodman, David; Bradley, Nori L.; Paras, Bradley, Williamson, Ian J.; Bizzochi, James

    2006-01-01

    While the positive uses for video games in an educational setting have also been established, the educational aim is usually made explicit. The goal of this research was to develop a video game wherein the educational aspect was implicitly embedded in the video game, such that the gameing activity remained interesting and relevant. Following a…

  6. Reconstructions of paleoclimate: Beyond the hockey stick. (Invited)

    NASA Astrophysics Data System (ADS)

    Nychka, D. W.; Li, B.

    2010-12-01

    Our understanding of past climate before the instrumental record is based on a variety of indirect information gleaned from climate proxies. Some well studied proxies include tree ring width and density, lake sediments, pollen indices and temperatures from bore holes. Combining such observations and including physical constraints on the target climate processes is well suited to recent methods in Bayesian statistics and is in contrast to previous methods used for paleoclimate reconstruction. This talk gives an introduction to this new perspective. To reconstruct past temperatures a traditional approach views the proxies as imperfect "thermometers" and calibrates them with instrument observations during a period where both are present. With this calibration one uses the proxies to predict temperature in other periods. This direct approach has the disadvantage that is it difficult to quantify the uncertainty of the reconstruction and to account for proxies that respond to temperature at different temporal and spatial scales. In addition, when different subsets of proxies are available for different reconstruction periods it is problematic to produce a single consistent and continuous reconstruction. A Bayesian hierarchical method demands more assumptions on the target climate process but also produces a more consistent analysis that addresses these shortcomings. The basic idea is to divide the statistical model into three distinct levels: a data level where the proxy measurement is related to the climate process, a process level that asserts a statistical model for the climate process and finally a level that puts prior distributions on unknown statistical parameters. With these statistical models in place, the relationships are inverted using Bayes theorem to give a distribution of the climate process given the proxy data and instrumental record. In the past, this inversion has been difficult to carry out analytically but with more abundant computational resources these computations can now be done using Monte Carlo techniques (e.g. Markov Chain Monte Carlo). Although this hierarchy of statistical models may seem to require more assumptions some of these need to be tacitly assumed in more traditional approaches. Also, assumptions on the climate process can build in basic climate constraints, such as energy balances, that are both reasonable and can produce a more accurate reconstruction. As an example, a reconstruction for Northern Hemisphere annual temperatures will be presented. This reconstruction takes advantage of several forcing series (e.g CO2 concentrations) as covariates and also provides an ensemble of reconstructions to convey the uncertainty in the analysis. This framework is also suitable for reconstructions of spatial fields and of several climate variables, such as temperature and precipitation, simultaneously.

  7. Spin-down of a rotating air hockey disk

    NASA Astrophysics Data System (ADS)

    Weidman, Patrick; Julien, Keith

    2013-11-01

    We extend the work of Weidman (APS, DFD 2008) on the steady float height of a rotating disk to formulate and solve for the unsteady behavior of spin-down to rest. A similarity reduction of the Navier-Stokes equations reduces the problem to a coupled pair of partial differential equations in space and time. For a disk of fixed radius and density, the PDE's must be solved taking into account constraints imposed by the aerodynamic torque and aerodynamic lift. Thus the full solution for the unsteady azimuthal and axial dynamics of the disk can be obtained for given initial values of disk Reynolds number R = W h / ν and dimensionless disk rotation speed S =√{ 2} Ωh / W , where h is the float height, W is the fluid levitation velocity, Ω is the disk rotation rate, and ν is the kinematic viscosity of the fluid. Integrations reveal interesting families of solutions when plotted over steady solution curves in R- S parameter space and vindicate the quasi-steady spin-down theory reported in earlier work, valid only in a restricted region of parameter space.

  8. Insulin Delivery System

    NASA Technical Reports Server (NTRS)

    1988-01-01

    When Programmable Implantable Medication System (PIMS) is implanted in human body, it delivers precise programmed amounts of insulin over long periods of time. Mini-Med Technologies has been refining the Technologies since initial development at APL. The size of a hockey puck, and encased in titanium shell, PIMS holds about 2 1/2 teaspoons of insulin at a programmed basal rate. If a change in measured blood sugar level dictates a different dose, the patient can vary the amount of insulin delivered by holding a small radio transceiver over the implanted system and dialing in a specific program held in the PIMS computer memory. Insulin refills are accomplished approximately 4 times a year by hypodermic needle.

  9. Experimental measurement and numerical simulation of residual stresses in a carburized layer of a 5120 steel

    SciTech Connect

    Rangaswamy, P.; Bourke, M.A.M.; Shipley, J.C.; Goldstone, J.A.

    1995-09-01

    A combined experimental and numerical study of residual stress and microstructure has been performed for a carburized steel 5120 specimen. Specimens were cut from 5120 steel bar stock, in the shape of hockey pucks and were subsequently carburized and quenched. X-ray diffraction was used to record stress profiles through the case for the martensite and retained austenite on the two flat surfaces oriented up and down during the quench. Layer removal was performed by electropolishing. Rietveld analysis was used to determine the lattice parameters of the phases at each depth varying with both carbon content and stress. The experimental measurements are compared with a numerical simulation of the phase transformation and the metallurgical changes following the carburization and quench. Results am discussed in the context of the microstructure and the role played by the retained austenite in interpretation. In addition the carbon profile obtained from the lattice parameters is compared with profiles measured using burnout.

  10. Characteristics and Applications of a High Performance, Miniaturized, Infrasound Sensor

    NASA Astrophysics Data System (ADS)

    Rothman, J. L.; Marriott, D. A.

    2015-12-01

    Infrasound Sensors have been used for many years to monitor a large number of geophysical phenomena and manmade sources. Due to their large size and power consumption these sensors have typically been deployed in fixed arrays, portable arrays have required trucks to transport the sensors and support equipment. A high performance, miniaturized, infrasound microphone has been developed to enable mobile infrasound measurements that would otherwise be impractical. The new device is slightly larger than a hockey puck, weighs 200g, and consumes less than 150mW. The sensitivity is 0.4V/Pa and self noise at 1Hz is less than 0.63μPa²/Hz. The characteristics were verified using a calibrator tracable to the Los Alamos calibration chamber. Field tests have demonstrated the performance is comparable to a Chaparral model 25. Applications include man portable arrays, mobile installations, and UAV based measurements.

  11. Non-ideal detonation behaviour of PBX 9502

    NASA Astrophysics Data System (ADS)

    Schoch, Stefan; Nikiforakis, Nikos

    2009-06-01

    Numerical experiments are performed investigating the non-ideal detonation behaviour of PBX 9502 in two setups. In the first setup we consider a three-dimensional rate stick experiment. A booster charge initiates a reaction front leading to a curved detonation wave. The numerical results are compared to theory and experimental evidence. The effects of weak and strong confinement are discussed. The second setup considers the so called ``hockey puck experiment.'' Experimental results show the appearance of a dead zone due to the effect of the geometry. This is captured by the numerical results, which also reveal that the initially spherical detonation is diffracted leading to local detonation failure. The numerical simulations are performed by solving a mathematical model for a three-phase medium based on the Euler equations. The numerical results are obtained using high-resolution shock-capturing methods combined with adaptive mesh refinement.

  12. Chemical routes to synthesize lithium cobalt oxide powders for rechargeable lithium batteries

    SciTech Connect

    Gallet, D.; Waghray, A.; Kumta, P.N.

    1996-12-31

    Lithium cobalt oxide (LiCoO{sub 2}) is known to be a good cathode material for high voltage (4V) rechargeable Li-ion batteries. New chemical routes based on aqueous solution chemistry have been developed to synthesize molecularly mixed precursors that transform to form LiCoO{sub 2} at temperatures as low as 400{degrees}C. The resultant oxide powders are nanocrystalline ({approx} 20-40 nm) and exhibit unique morphologies and microstructures depending on the molecular environment of the ions in solution. Cathodes fabricated from the oxide powders and tested in {open_quote}hockey-puck{close_quote} test cells exhibited specific capacities of about 135 mAh/g with a reversible range close to 0.5 Li ions. Results of the phase evolution and microstructural analysis are discussed in relation to the electrochemical performance of the cathodes.

  13. Management: Global positioning and wireless dispatching

    SciTech Connect

    Wood, M.

    1996-02-01

    Over the last several years, my company has been supplying many service companies with wireless dispatching solutions. Recently the impact of the system has been greatly increased with the introduction of a GPS (Global Position Systems) interface. This adds visual recognition as to the whereabouts of each vehicle within the customer service area. The only equipment required in the field for GPS is a transmit/receive device and a wireless modem, one mounted out of the way in the vehicle (under the seat) and a {open_quotes}hockey puck{close_quotes} size unit on the roof of the vehicle. The GPS received unit and wireless modem are used to retrieve the longitude, latitude and ground speed coordinates and transmit them back to the host system.

  14. Imaging and detection of mines from acoustic measurements

    NASA Astrophysics Data System (ADS)

    Witten, Alan J.; DiMarzio, Charles A.; Li, Wen; McKnight, Stephen W.

    1999-08-01

    A laboratory-scale acoustic experiment is described where a buried target, a hockey puck cut in half, is shallowly buried in a sand box. To avoid the need for source and receiver coupling to the host sand, an acoustic wave is generated in the subsurface by a pulsed laser suspended above the air-sand interface. Similarly, an airborne microphone is suspended above this interface and moved in unison with the laser. After some pre-processing of the data, reflections for the target, although weak, could clearly be identified. While the existence and location of the target can be determined by inspection of the data, its unique shape can not. Since target discrimination is important in mine detection, a 3D imaging algorithm was applied to the acquired acoustic data. This algorithm yielded a reconstructed image where the shape of the target was resolved.

  15. Particle-In-Cell Analysis of an Electric Antenna for the BepiColombo/MMO spacecraft

    NASA Astrophysics Data System (ADS)

    Miyake, Yohei; Usui, Hideyuki; Kojima, Hirotsugu

    The BepiColombo/MMO spacecraft is planned to provide a first electric field measurement in Mercury's magnetosphere by mounting two types of the electric antennas: WPT and MEFISTO. The sophisticated calibration of such measurements should be performed based on precise knowledge of the antenna characteristics in space plasma. However, it is difficult to know prac-tical antenna characteristics considering the plasma kinetics and spacecraft-plasma interactions by means of theoretical approaches. Furthermore, some modern antenna designing techniques such as a "hockey puck" principle is applied to MEFISTO, which introduces much complexity in its overall configuration. Thus a strong demand arises regarding the establishment of a nu-merical method that can solve the complex configuration and plasma dynamics for evaluating the electric properties of the modern instrument. For the self-consistent antenna analysis, we have developed a particle simulation code named EMSES based on the particle-in-cell technique including a treatment antenna conductive sur-faces. In this paper, we mainly focus on electrostatic (ES) features and photoelectron distri-bution in the vicinity of MEFISTO. Our simulation model includes (1) a photoelectron guard electrode, (2) a bias current provided from the spacecraft body to the sensing element, (3) a floating potential treatment for the spacecraft body, and (4) photoelectron emission from sunlit surfaces of the conductive bodies. Of these, the photoelectron guard electrode is a key technol-ogy for producing an optimal condition of plasma environment around MEFISTO. Specifically, we introduced a pre-amplifier housing called puck located between the conductive boom and the sensor wire. The photoelectron guard is then simulated by forcibly fixing the potential difference between the puck surface and the spacecraft body. For the modeling, we use the Capacity Matrix technique in order to assure the conservation condition of total charge owned by the

  16. Lead isotope ratio measurements as indicators for the source of lead poisoning in Mute swans (Cygnus olor) wintering in Puck Bay (northern Poland).

    PubMed

    Binkowski, Łukasz J; Meissner, Włodzimierz; Trzeciak, Marta; Izevbekhai, Kelvin; Barker, James

    2016-12-01

    Lead (Pb) poisoning is most commonly linked amongst anthropogenically-caused deaths in waterfowl and this is often associated with hunting and fishing activities. However, the exact identification of the source may be difficult with commonly-used techniques. We have studied isotope ratios using Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) to investigate the source of Pb in the blood of Mute swans (n = 49) wintering in northern Poland. We compared the values of isotopic ratios from blood and ammunition pellets available on the Polish market. The mean Pb concentrations found was 0.241 μg/g (w/w) and nearly half of the blood specimens had elevated Pb levels (higher than the cited 0.23 μg/g w/w threshold of poisoning). Only the mean 208/206 Pb isotope ratio was similar in blood and pellet samples. Mean ratios of isotopes 206/204, 206/207 and 208/207 in swans' blood and in pellets differed significantly. Moreover, coefficients of variation were higher in blood samples than in pellets. These discrepancies and significant differences in abundance of (204)Pb and (207)Pb isotopes in both materials indicated that pellets available today on the Polish market were not the source of Pb in the blood of Mute swans wintering in northern Poland.

  17. A resolution congratulating the University of Minnesota Duluth men's ice hockey team on winning their first National Collegiate Athletic Association (NCAA) Division I Men's Hockey National Championship.

    THOMAS, 112th Congress

    Sen. Klobuchar, Amy [D-MN

    2011-04-14

    05/04/2011 Resolution agreed to in Senate without amendment and with a preamble by Unanimous Consent. (text: CR S2695) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  18. A resolution congratulating the Alaska Aces hockey team on winning the 2014 Kelly Cup as champions of the East Coast Hockey League.

    THOMAS, 113th Congress

    Sen. Begich, Mark [D-AK

    2014-06-12

    06/12/2014 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S3673; text as passed Senate: CR S3671) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  19. A resolution congratulating the Boston College men's ice hockey team on winning its fifth National Collegiate Athletic Association Division I Men's Hockey Championship.

    THOMAS, 112th Congress

    Sen. Kerry, John F. [D-MA

    2012-04-25

    04/25/2012 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S2741-2742; text as passed Senate: CR S2742; text of measure as introduced: CR S2736) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  20. A resolution congratulating the University of Minnesota women's ice hockey team on winning its second straight National Collegiate Athletic Association Women's Ice Hockey Championship.

    THOMAS, 113th Congress

    Sen. Klobuchar, Amy [D-MN

    2013-04-25

    04/25/2013 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S3060; text as passed Senate: CR S3049) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  1. Particle-In-Cell Modeling and Analysis of an Electric Antenna for the BepiColombo/MMO spacecraft

    NASA Astrophysics Data System (ADS)

    Miyake, Yohei; Usui, Hideyuki; Kojima, Hirotsugu

    2010-05-01

    The sophisticated calibration of a space-based electric antenna should be performed based on precise knowledge of electric antenna characteristics in space plasma environment. However, it is often difficult to know practical antenna characteristics considering the effects of plasma kinetics and spacecraft-plasma interactions by means of only theoretical approaches. Furthermore, some modern electric field instruments, such as the Cluster EFW instrument and MEFISTO for the BepiColombo/MMO spacecraft, are designed based on a ``hockey puck'' principle, which introduces much complexity in their overall configurations. Thus a strong demand arises regarding the establishment of a numerical method that can solve the complex configuration and plasma dynamics for evaluating the electric properties of such modern instruments. For the self-consistent antenna analysis, we have newly developed an electromagnetic (EM) particle simulation code named EMSES. The code is based on the particle-in-cell technique and also supports a treatment of inner boundaries describing spacecraft conductive surfaces. This enables us to naturally include the effects of the inhomogeneous plasma environment such as a plasma and photoelectron sheaths created around the antenna. The support of the full EM treatment is also important to apply our tool to antenna properties for not only electrostatic (ES) but also EM plasma waves. In the current study, we mainly focus on ES features and photoelectron distribution in the vicinity of the electric field instrument MEFISTO. Our simulation model includes (1) a photoelectron guard electrode, (2) a bias current provided from the spacecraft body to the sensing element, (3) a floating potential treatment for the spacecraft body, and (4) photoelectron emission from sunlit surfaces of the conductive bodies. Of these, the photoelectron guard electrode is a key technology for producing an optimal condition of plasma environment around MEFISTO. Specifically, we

  2. An Experimental Investigation of Detonation Corner-Turning Using High Resolution Radiography

    SciTech Connect

    Molitoris, J D; Andreski, H G; Garza, R G; Batteux, J D; Souers, P C

    2006-07-19

    We have performed experiments investigating detonation corner turning over a range of high-explosives including LX-17, Composition B, LX-04 and Tritonal. The primary diagnostic utilized here was a new high-resolution x-ray system that was capable of recording a time sequence of the detonation process as it negotiated the corner of interest and propagated. For LX-17 our data detail the formation of a significant dead-zone. Although the detonation eventually turned the corner in LX-17, the dead zone persisted to late times and evidence exists that it never was consumed by either detonation or fast combustion processes. In LX-17 the detonations ability to corner-turn increases as the density is reduced. Furthermore, lowering the density decreases the size of the dead-zone and alters its shape. The other high-explosives investigated were able to turn the corner immediately with no indication of any dead-zone formation.

  3. Hockey Gloves, Chocolate Bars, Asbestos, and Why Trees Fall in the Forest: Teaching Global Economics.

    ERIC Educational Resources Information Center

    Mackwood, Gae

    1991-01-01

    Discusses the need for global education in the face of economic influences that result in pollution and the exploitation of developing nations. Cites the difficulties faced by less developed countries that try to compete in world trade. Urges educators to teach students to take morally responsible positions on global relations. (SG)

  4. Coach Selections and the Relative Age Effect in Male Youth Ice Hockey

    ERIC Educational Resources Information Center

    Hancock, David J.; Ste-Marie, Diane M.; Young, Bradley W.

    2013-01-01

    Relative age effects (RAEs; when relatively older children possess participation and performance advantages over relatively younger children) are frequent in male team sports. One possible explanation is that coaches select players based on physical attributes, which are more likely witnessed in relatively older athletes. Purpose: To determine if…

  5. The Validity and Reliability of a Performance Assessment Procedure in Ice Hockey

    ERIC Educational Resources Information Center

    Nadeau, Luc; Richard, Jean-Francois; Godbout, Paul

    2008-01-01

    Background: Coaches and physical educators must obtain valid data relating to the contribution of each of their players in order to assess their level of performance in team sport competition. This information must also be collected and used in real game situations to be more valid. Developed initially for a physical education class context, the…

  6. Information Structure in Finnish Live Ice Hockey Reporting: An Answer to Tomlin (1983).

    ERIC Educational Resources Information Center

    Hiirikoski, Juhani

    The purpose of this article is to investigate ways that the grammatical and semantic structures of the Finnish clause limit its possibilities for expressing information structure. The study aims to discover whether there is a correlation between the semantic structure of the sentence and the possibility of using the inverted word order for…

  7. Exploring Coaching Actions Based on Developed Values: A Case Study of a Female Hockey Coach

    ERIC Educational Resources Information Center

    Callary, Bettina; Werthner, Penny; Trudel, Pierre

    2013-01-01

    There are few empirical studies that demonstrate how values are developed and how they are linked to coaching actions. There can be a discrepancy between the statement of coaches' values and their actual coaching actions. In order to examine how coaching actions are influenced by values that are developed over a lifetime, the purpose of this…

  8. Learning How to Coach: The Different Learning Situations Reported by Youth Ice Hockey Coaches

    ERIC Educational Resources Information Center

    Wright, Trevor; Trudel, Pierre; Culver, Diane

    2007-01-01

    Background: Large-scale coach education programs have been developed in many countries around the world to help prepare coaches for their important role. Coaches have said that they also learn to coach from experience, starting from when they were young athletes until their current coaching positions. Finally, in the last decade, Internet…

  9. A resolution honoring the hockey team of East Side High School in Newark, New Jersey.

    THOMAS, 111th Congress

    Sen. Menendez, Robert [D-NJ

    2009-07-21

    07/21/2009 Referred to the Committee on the Judiciary. (text of measure as introduced: CR S7793) (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  10. The uncertain hockey stick: a statistical perspective on the reconstruction of past temperatures

    NASA Astrophysics Data System (ADS)

    Nychka, Douglas

    2007-03-01

    A reconstruction of past temperatures based on proxies is inherently a statistical process and a deliberate statistical model for the reconstruction can also provide companion measures of uncertainty. This view is often missed in the heat of debating the merits of different analyses and interpretations of paleoclimate data. Although statistical error is acknowledged to be just one component of the total uncertainty in a reconstruction, it can provide a valuable yardstick for comparing different reconstructions or drawing inferences about features. In this talk we suggest a framework where the reconstruction is expressed as a conditional distribution of the temperatures given the proxies. Random draws from this distribution provide an ensemble of reconstructions where the spread among ensemble members is a valid statistical measure of uncertainty. This approach is illustrated for Northern Hemisphere temperatures and the multi-proxy data used by Mann, Bradley and Hughes (1999). Here we explore the scope of the statistical assumptions needed to carry through a rigorous analysis and use Monte Carlo sampling to determine the uncertainty in maxima or other complicated statistics in the reconstructed series. The principles behind this simple example for the Northern Hemisphere can be extended to regional reconstructions, incorporation of additional types proxies and the use of statistics from numerical models.

  11. The `hockey stick' and the 1990s: a statistical perspective on reconstructing hemispheric temperatures

    NASA Astrophysics Data System (ADS)

    Li, Bo; Nychka, Douglas W.; Ammann, Caspar M.

    2007-10-01

    The short instrumental record of about 100-150 yr forces us to use proxy indicators to study climate over long timescales. The climate information in these indirect data is embedded in considerable noise, and the past temperature reconstructions are therefore full of uncertainty, which blurs the understanding of the temperature evolution. To date, the characterization and quantification of uncertainty have not been a high priority in reconstruction procedures. Here we propose a new statistical methodology to explicitly account for three types of uncertainties in the reconstruction process. Via ensemble reconstruction, we directly obtain the distribution of decadal maximum as well as annual maximum. Our method is an integration of linear regression, bootstrapping and cross-validation techniques, and it (1) accounts for the effects of temporal correlation of temperature; (2) identifies the variability of the estimated statistical model and (3) adjusts the effects of potential overfitting. We apply our method to the Northern Hemisphere (NH) average temperature reconstruction. Our results indicate that the recent decadal temperature increase is rapidly overwhelming previous maxima, even with uncertainty taken into account, and the last decade is highly likely to be the warmest in the last millennium.

  12. Protein carbonyl levels correlate with performance in elite field hockey players.

    PubMed

    Rosa-Lima, Frederico Luis; Lannes, Luiz; Viana-Gomes, Diego; Pierucci, Anna Paola T R; Salerno, Verônica P

    2015-07-01

    Excess and incorrectly selected exercise can degrade athletic performance from an imbalance in redox homeostasis and oxidative stress, but well-planned training and nutrition can improve antioxidant capacity. The aim of the study was to investigate how nutrient intake could influence oxidative stress and cell lesion biomarkers after 5 days of training followed by a game. Blood was collected from 10 athletes at the start of training (basal), after training (pre-game), and postgame. Their acceleration capacity also was measured pre- and postgame. Blood analysis showed an increase in lactate concentration postgame (13%) and total antioxidant capacity increased both pre-game (13.1%) and postgame (12.7%), all in comparison with basal levels. An oxidative stress marker, protein carbonyl (PC), increased 3-fold over the course of the game, which correlated with a decreased acceleration (r = 0.749). For biomarkers of tissue damage, creatine kinase and aspartate transaminase (AST) increased postgame by 150% and 75%, respectively. The AST variation had a high negative correlation with energy and carbohydrate consumption and a moderate correlation with lipid and vitamin C intake. Protein intake had a positive but moderate correlation with reduced glutathione. The observed correlations suggest that nutritional monitoring can improve exercise physiological homeostasis and that PC serves as a good biomarker for oxidative stress and performance loss.

  13. Heat transfer at the mold-metal interface in permanent mold casting of aluminum alloys project. Quarterly project status report, April 1--June 30, 1998

    SciTech Connect

    Pehlke, R.D.; Hao, S.W.

    1998-06-30

    Extensive progress in development of an HTC (heat transfer coefficient) Evaluator and in the preparation of the experiments at CMI and Amcast have been achieved in the last three months. The interface of the HTC Evaluator has been developed in Visual C++ for the PC platform. It provides a tool to collect and store the published data on heat transfer coefficients in a database for further analysis. It also supports the mathematical model for evaluation of heat transfer coefficients. More than 100 papers related to this project have been cited and most of them have been collected. The preparation of the experiments at CMI is almost completed. A hockey-puck mold has been selected for the experiments for squeeze casting and semi-solid casting. A direct cavity pressure measurement system was purchased from Kistler. The pressure probes and data acquisition software as well as the necessary accessories have been delivered. The instrumented mold modification has been designed and the modifications completed. At Amcast Automotive, a new wheel-like mold for low-pressure permanent mold casting was designed. The CAD file for mold fabrication has been generated. The modeling of the casting has been done. An extensive survey on the ultrasonic gap formation measurement was fulfilled. It is concluded that the ultrasonic probe is capable of measuring a gap under the authors` casting conditions. In the last three months, four project meetings has been organized and held with the industrial partners.

  14. Square lattice honeycomb tri-carbide fuels for 50 to 250 KN variable thrust NTP design

    NASA Astrophysics Data System (ADS)

    Anghaie, Samim; Knight, Travis; Gouw, Reza; Furman, Eric

    2001-02-01

    Ultrahigh temperature solid solution of tri-carbide fuels are used to design an ultracompact nuclear thermal rocket generating 950 seconds of specific impulse with scalable thrust level in range of 50 to 250 kilo Newtons. Solid solutions of tri-carbide nuclear fuels such as uranium-zirconium-niobium carbide. UZrNbC, are processed to contain certain mixing ratio between uranium carbide and two stabilizing carbides. Zirconium or niobium in the tri-carbide could be replaced by tantalum or hafnium to provide higher chemical stability in hot hydrogen environment or to provide different nuclear design characteristics. Recent studies have demonstrated the chemical compatibility of tri-carbide fuels with hydrogen propellant for a few to tens of hours of operation at temperatures ranging from 2800 K to 3300 K, respectively. Fuel elements are fabricated from thin tri-carbide wafers that are grooved and locked into a square-lattice honeycomb (SLHC) shape. The hockey puck shaped SLHC fuel elements are stacked up in a grooved graphite tube to form a SLHC fuel assembly. A total of 18 fuel assemblies are arranged circumferentially to form two concentric rings of fuel assemblies with zirconium hydride filling the space between assemblies. For 50 to 250 kilo Newtons thrust operations, the reactor diameter and length including reflectors are 57 cm and 60 cm, respectively. Results of the nuclear design and thermal fluid analyses of the SLHC nuclear thermal propulsion system are presented. .

  15. CREST modelling of PBX 9502 corner turning experiments at different initial temperatures

    NASA Astrophysics Data System (ADS)

    Whitworth, N. J.

    2014-05-01

    Corner turning is an important problem in regard to detonation wave propagation in TATB-based explosives. Experimentally, a sudden change in the direction of the propagating wave, such as turning a sharp corner, can result in dead-zones being left behind in the corner turn region, with the observed behaviour being particularly sensitive to the initial temperature of the explosive. In this paper, the entropy-dependent CREST reactive burn model is used to simulate corner turning experiments on the TATB-based explosive PBX 9502. Calculated results of double cylinder tests at three different initial temperatures (-54°C, ~23°C, and 75°C), and a "hockey puck" experiment at ambient temperature, are compared to the corresponding test measurements. The results show that the model is able to: (i) calculate persistent dead-zones in PBX 9502 without recourse to any shock desensitisation treatment, and (ii) predict changes in corner turning behaviour with initial temperature using one set of coefficients.

  16. Using Fiber Optics to Measure Carrier Drift Velocity of Germanium at 40mK

    NASA Astrophysics Data System (ADS)

    Lam, Albert

    2010-11-01

    The Cryogenic Dark Matter Search (CDMS) uses ultrapure germanium detectors at milliKelvin temperatures to attempt to directly detect weakly interacting massive particles (WIMPs), a candidate for dark matter. When some particle interacts with the crystal structure, ionization and phonon signals are produced. Each particle interaction gives off a unique ratio of ionization signal to phonon signal. In this way, background noise can be separated from events that may involve WIMPs. Current germanium detectors are about the size of a hockey puck. If detectors can be made larger, there would be a greater probability of having a WIMP interaction. To make larger detectors, we need to better understand carrier transport processes in the germanium detectors. So, we measured the carrier drift velocity at 40milliKelvin, the temperature at which detectors operate. The carrier drift velocity gives us insight into how much impurity is present in the germanium detectors. We made this measurement using a fiber optics line. The fiber optics line allowed us to carry light from a 780nm laser diode at room temperature, into our dilution refrigerator and onto a germanium detector at 40milliKelvin. A laser diode allowed us to create electron-hole pairs on the surface of a germanium detector in a much more precise way than a radiation source.

  17. Bose-Einstein condensation in dark power-law laser traps

    SciTech Connect

    Jaouadi, A.; Gaaloul, N.; Viaris de Lesegno, B.; Pruvost, L.; Telmini, M.; Charron, E.

    2010-08-15

    We investigate theoretically an original route to achieve Bose-Einstein condensation using dark power-law laser traps. We propose to create such traps with two crossing blue-detuned Laguerre-Gaussian optical beams. Controlling their azimuthal order l allows for the exploration of a multitude of power-law trapping situations in one, two, and three dimensions, ranging from the usual harmonic trap to an almost square-well potential, in which a quasihomogeneous Bose gas can be formed. The usual cigar-shaped and disk-shaped Bose-Einstein condensates obtained in a 1D or 2D harmonic trap take the generic form of a 'finger' or of a 'hockey puck' in such Laguerre-Gaussian traps. In addition, for a fixed atom number, higher transition temperatures are obtained in such configurations when compared with a harmonic trap of the same volume. This effect, which results in a substantial acceleration of the condensation dynamics, requires a better but still reasonable focusing of the Laguerre-Gaussian beams.

  18. Electrochemical characterization of thio sol-gel derived titanium sulfide (TiS{sub 2}) powders with unique morphologies

    SciTech Connect

    Sriram, M.A.; Kumta, P.N.

    1996-12-31

    A novel thio sol-gel process utilizing titanium alkoxide as the metal source has been used to synthesize TiS{sub 2} powders exhibiting uniquely different morphologies. The pure alkoxide and its partially modified form using benzene sulfonic acid (BSA) have been reacted with H{sub 2}S to yield a solid precursor. Upon heat treatment in flowing H{sub 2}S the precursors were converted to TiS{sub 2} exhibiting distinctly different morphologies. These powders have been characterized for their chemical stoichiometry (using X-ray diffraction). At the same time the sulfide was also prepared using conventional techniques involving the reaction of the individual elements in a sealed evacuated quartz ampoule at elevated temperatures of 500{degrees}C. The morphologies of both, the thio sol-gel derived and conventionally synthesized powders have been compared using scanning electron microscopy (SEM). Preliminary electrochemical tests were also performed by fabricating test cathodes of these materials and using them in {open_quotes}hockey puck{close_quotes} cells incorporating lithium as both the anode and the reference electrodes. These studies were conducted to analyze the effect of the different morphologies of the synthesized powders on their electrochemical performance.

  19. CREST Modelling of PBX 9502 Corner Turning Experiments at Different Initial Temperatures

    NASA Astrophysics Data System (ADS)

    Whitworth, Nicholas

    2013-06-01

    Corner turning is an important problem in regard to detonation wave propagation in TATB-based explosives. Experimentally, a sudden change in direction of the propagating wave, such as turning a sharp corner, can result in dead-zones being left behind in the corner turn region, with the observed behaviour being particularly sensitive to the initial temperature of the explosive. In this paper, the entropy-dependent CREST reactive burn model is used to simulate corner turning experiments on the TATB-based explosive PBX 9502. Calculated results of double cylinder tests at three different initial temperatures (-54°C, 25°C, and 75°C), and a ``hockey puck'' experiment at ambient temperature, are compared to the corresponding test measurements. The results show that the model is able to: (i) calculate persistent dead-zones in PBX 9502 without recourse to any shock desensitisation treatment, and (ii) predict changes in corner turning behaviour with initial temperature using one set of coefficients.

  20. Electron Beam Diagnostics in Plasmas Based on Electron Beam Ionization

    NASA Astrophysics Data System (ADS)

    Leonhardt, Darrin; Leal-Quiros, Edbertho; Blackwell, David; Walton, Scott; Murphy, Donald; Fernsler, Richard; Meger, Robert

    2001-10-01

    Over the last few years, electron beam ionization has been shown to be a viable generator of high density plasmas with numerous applications in materials modification. To better understand these plasmas, we have fielded electron beam diagnostics to more clearly understand the propagation of the beam as it travels through the background gas and creates the plasma. These diagnostics vary greatly in sophistication, ranging from differentially pumped systems with energy selective elements to metal 'hockey pucks' covered with thin layers of insulation to electrically isolate the detector from the plasma but pass high energy beam electrons. Most importantly, absolute measurements of spatially resolved beam current densities are measured in a variety of pulsed and continuous beam sources. The energy distribution of the beam current(s) will be further discussed, through experiments incorporating various energy resolving elements such as simple grids and more sophisticated cylindrical lens geometries. The results are compared with other experiments of high energy electron beams through gases and appropriate disparities and caveats will be discussed. Finally, plasma parameters are correlated to the measured beam parameters for a more global picture of electron beam produced plasmas.

  1. Genetics Home Reference: X-linked severe combined immunodeficiency

    MedlinePlus

    ... Chinen J, Puck JM. Successes and risks of gene therapy in primary immunodeficiencies. J Allergy Clin Immunol. 2004 ... Review. Citation on PubMed Puck JM, Malech HL. Gene therapy for immune disorders: good news tempered by bad ...

  2. A resolution congratulating the Alaska Aces hockey team on winning the 2011 Kelly Cup and becoming the East Coast Hockey League champions for the second time in team history.

    THOMAS, 112th Congress

    Sen. Begich, Mark [D-AK

    2011-05-24

    05/24/2011 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S3288; text as passed Senate: CR S3288; text of measure as introduced: CR S3280) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  3. Measurement of Hybrid III Head Impact Kinematics Using an Accelerometer and Gyroscope System in Ice Hockey Helmets.

    PubMed

    Allison, Mari A; Kang, Yun Seok; Maltese, Matthew R; Bolte, John H; Arbogast, Kristy B

    2015-08-01

    Helmet-based instrumentation is used to study the biomechanics of concussion. The most extensively used systems estimate rotational acceleration from linear acceleration, but new instrumentation measures rotational velocity using gyroscopes, potentially reducing error. This study compared kinematics from an accelerometer and gyroscope-containing system to reference measures. A Hybrid III (HIII) adult male anthropometric test device head and neck was fit with two helmet brands, each instrumented with gForce Tracker (GFT) sensor systems in four locations. Helmets were impacted at various speeds and directions. Regression relationships between GFT-measured and reference peak kinematics were quantified, and influence of impact direction, sensor location, and helmet brand was evaluated. The relationship between the sensor output and the reference acceleration/velocity experienced by the head was strong. Coefficients of determination for data stratified by individual impact directions ranged from 0.77 to 0.99 for peak linear acceleration and from 0.78 to 1.0 for peak rotational velocity. For the data from all impact directions combined, coefficients of determination ranged from 0.60 to 0.80 for peak resultant linear acceleration and 0.83 to 0.91 for peak resultant rotational velocity. As expected, raw peak resultant linear acceleration measures exhibited large percent differences from reference measures. Adjustment using regressions resulted in average absolute errors of 10-15% if regression adjustments were done by impact direction or 25-40% if regressions incorporating data from all impact directions were used. Average absolute percent differences in raw peak resultant rotational velocity were much lower, around 10-15%. It is important to define system accuracy for a particular helmet brand, sensor location, and impact direction in order to interpret real-world data.

  4. Employment Law, Negotiation, and the Business Environment: A Cooperative Collective Bargaining Negotiation of the National Hockey League Lockout of 2004

    ERIC Educational Resources Information Center

    Ciocchetti, Corey A.

    2008-01-01

    Employment law is a "must-cover" subject in business environment courses. Comparing the plethora of topics requiring coverage with the limited time devoted to employment law during a typical academic term, other important employment subjects--such as negotiation and collective bargaining--commonly receive short shrift. This article offers a…

  5. Heat transfer at the mold-metal interface in permanent mold casting of aluminum alloys project. Annual project status report for the period October 1, 1997 to September 30, 1998

    SciTech Connect

    Pehlke, R.D.; Hao, S.W.

    1998-09-30

    In the first year of this three-year project, substantial progress has been achieved. This project on heat transfer coefficients in metal permanent mold casting is being conducted in three areas. They are the theoretical study at the University of Michigan, the experimental investigations of squeeze casting and semi-solid casting at CMI-Tech Center, and the experimental investigation of low pressure permanent mold casting at Amcast Automotive. U-M did an initial geometry which was defined for ProCAST to solve, and then a geometry half the size was defined and solved using the same boundary conditions. A conceptual mold geometry was examined and is represented as an axisymmetric element.Furthermore, the influences of the localized heat transfer coefficients on the casting process were carefully studied. The HTC Evaluator has been proposed and initially developed by the U-M team. The Reference and the Database Modules of the HTC Evaluator have been developed, and extensively tested. A series of technical barriers have been cited and potential solutions have been surveyed. At the CMI-Tech Center, the Kistler direct cavity pressure measurement system has been purchased and tested. The calibrations has been evaluated. The probe is capable of sensing a light finger pressure. The experimental mold has been designed and modified. The experimental mold has been designed and modified. The first experiment is scheduled for October 14, 1998. The geometry of the experimental hockey-puck casting has been given to the U-M team for numerical analysis.

  6. Insensitive HE EOS

    SciTech Connect

    Ree, F.H.; Viecelli, J.; van Thiel, M.

    1997-12-01

    A typical insensitive high explosive such as LX-17 has a large carbon-content and produces hydrogen fluoride (HF) as a detonation product. It is also characterized by slow energy release as indicated by a large curvature of the detonation front. We analyze these new physics issues which are needed to predict the performance of a insensitive high explosive. (U)

  7. Modeling Hemispheric Detonation Experiments in 2-Dimensions

    SciTech Connect

    Howard, W M; Fried, L E; Vitello, P A; Druce, R L; Phillips, D; Lee, R; Mudge, S; Roeske, F

    2006-06-22

    Experiments have been performed with LX-17 (92.5% TATB and 7.5% Kel-F 800 binder) to study scaling of detonation waves using a dimensional scaling in a hemispherical divergent geometry. We model these experiments using an arbitrary Lagrange-Eulerian (ALE3D) hydrodynamics code, with reactive flow models based on the thermo-chemical code, Cheetah. The thermo-chemical code Cheetah provides a pressure-dependent kinetic rate law, along with an equation of state based on exponential-6 fluid potentials for individual detonation product species, calibrated to high pressures ({approx} few Mbars) and high temperatures (20000K). The parameters for these potentials are fit to a wide variety of experimental data, including shock, compression and sound speed data. For the un-reacted high explosive equation of state we use a modified Murnaghan form. We model the detonator (including the flyer plate) and initiation system in detail. The detonator is composed of LX-16, for which we use a program burn model. Steinberg-Guinan models5 are used for the metal components of the detonator. The booster and high explosive are LX-10 and LX-17, respectively. For both the LX-10 and LX-17, we use a pressure dependent rate law, coupled with a chemical equilibrium equation of state based on Cheetah. For LX-17, the kinetic model includes carbon clustering on the nanometer size scale.

  8. 75 FR 24951 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-06

    ... Holdings L.P. G Lightning Properties, Ltd. G Palace Florida Properties L.P. G Lightning Hockey GP LLC. G Tampa Bay Arena, L.P. G Lightning Hockey LP. G Lightning Real Estate Investment GP LLC. 20100398 G...

  9. 75 FR 11538 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-11

    ... Lightning Properties, Ltd. G Palace Florida Properties L.P. G Lightning Hockey GP LLC G Tampa Bay Arena, L.P. G Lightning Hockey LP G Lightning Real Estate Investment GP LLC 20100398 G Roark Capital Partners...

  10. Establishing the Test-Retest Reliability & Concurrent Validity for the Repeat Ice Skating Test (RIST) in Adolescent Male Ice Hockey Players

    ERIC Educational Resources Information Center

    Power, Allan; Faught, Brent E.; Przysucha, Eryk; McPherson, Moira; Montelpare, William

    2012-01-01

    In this study the authors examine the test-retest reliability and concurrent validity of the Repeat Ice Skating Test (RIST). This was an on-ice field anaerobic test that measured average peak power and was validated with 3 anaerobic lab tests: (a) vertical jump, (b) the Margaria-Kalamen stair test, and (c) the Wingate Anaerobic Test. The…

  11. A resolution congratulating the University of North Carolina Tar Heels for winning the 2009 National Collegiate Athletic Association Field Hockey National Championship.

    THOMAS, 111th Congress

    Sen. Hagan, Kay R. [D-NC

    2009-12-17

    12/17/2009 Referred to the Committee on the Judiciary. (text of measure as introduced: CR S13393-13394) (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  12. Miniature Free-Flying Magnetometer Utilizing System-On-A-Chip Technology

    NASA Technical Reports Server (NTRS)

    Eyre, F. B.; Blaes, B. R.

    2001-01-01

    Four Free-Flying Magnetometers (FFMs), developed at the Jet Propulsion Laboratory (JPL) for the Enstrophy mission, were successfully deployed from the payload of a sounding rocket launched from Poker Flats, Alaska on February 11, 1999. The FFMs functioned successfully by synchronously measuring the vector magnetic field at 4 points separate from the payload and at relative distances up to 3 km, and communicated their data, in bursts, to the ground. This is the first time synchronized in-situ multipoint measurements of the Earth's magnetic field utilizing miniature spin-stabilized "sensorcraft" have been performed. The data they provided have enabled, for the first time, the direct measure of field-aligned current density and are enabling new science by determining the fine-scale structure of the currents in the Earth's ionosphere involved in the production of aurora. These proof-of-concept "hockey puck" (80 mm diameter, 38 mm height, 250 gram mass) FFMs were built using off-the-shelf commercial, industrial, and military grade surface-mount electronic components. Radiation-hard electronics was not required for the Enstrophy mission's short sub-orbital flight. The successful design, implementation, and flight demonstration of this 1st generation FFM design has provided a solid base for further development of a 2nd generation FFM design for planetary science applications. A reliable ultra-miniature radiation-hard 2nd-generation FFM utilizing System-On-A-Chip (SOAC) technologies is proposed. This design would be targeted for long-term planetary missions to investigate magnetospheric field configurations in regions having small-scale structure and to separate spatial and temporal variations. A fleet of short-lived (expendable) FFMs would be deployed into a targeted region to gather multiprobe vector magnetic field data. The FFMs would be ejected from a parent spacecraft at a speed of a few m/sec and would cover spatial volumes of order tens of kilometers for times of

  13. A rehabilitation tool for functional balance using altered gravity and virtual reality

    PubMed Central

    Oddsson, Lars IE; Karlsson, Robin; Konrad, Janusz; Ince, Serdar; Williams, Steve R; Zemkova, Erika

    2007-01-01

    Background There is a need for effective and early functional rehabilitation of patients with gait and balance problems including those with spinal cord injury, neurological diseases and recovering from hip fractures, a common consequence of falls especially in the elderly population. Gait training in these patients using partial body weight support (BWS) on a treadmill, a technique that involves unloading the subject through a harness, improves walking better than training with full weight bearing. One problem with this technique not commonly acknowledged is that the harness provides external support that essentially eliminates associated postural adjustments (APAs) required for independent gait. We have developed a device to address this issue and conducted a training study for proof of concept of efficacy. Methods We present a tool that can enhance the concept of BWS training by allowing natural APAs to occur mediolaterally. While in a supine position in a 90 deg tilted environment built around a modified hospital bed, subjects wear a backpack frame that is freely moving on air-bearings (cf. puck on an air hockey table) and attached through a cable to a pneumatic cylinder that provides a load that can be set to emulate various G-like loads. Veridical visual input is provided through two 3-D automultiscopic displays that allow glasses free 3-D vision representing a virtual surrounding environment that may be acquired from sites chosen by the patient. Two groups of 12 healthy subjects were exposed to either strength training alone or a combination of strength and balance training in such a tilted environment over a period of four weeks. Results Isokinetic strength measured during upright squat extension improved similarly in both groups. Measures of balance assessed in upright showed statistically significant improvements only when balance was part of the training in the tilted environment. Postural measures indicated less reliance on visual and/or increased use

  14. Plutonism at Different Crustal Levels of an Arc: Insights From the 5 to 40 km (Paleodepth) North Cascades Crustal Section, Washington

    NASA Astrophysics Data System (ADS)

    Miller, R. B.; Paterson, S. R.; Matzel, J. P.

    2008-12-01

    The crystalline core of the North Cascades preserves a Cretaceous crustal section that facilitates evaluation of pluton construction, emplacement, geometry, composition, and deformation at widely variable crustal levels (~5 to 40 km paleodepth) in a thick (> 55 km) continental magmatic arc. The oldest and largest pulse of plutonism was focused between 96-89 Ma when fluxes were a minimum of 3.9x10-6km3/yr/km of arc length, but the coincidence with regional crustal thickening and underthrusting of a cool outboard terrane resulted in relatively low mid- to deep-crustal temperatures for an arc. A second, smaller peak of magmatism at 78-71 Ma (minimum of 8.2x10-7km3/yr/km of arc length) occurred during regional transpression. Tonalite dominates at all levels of the section. Intrusions range from large plutons to thin (< 50 m) dispersed sheets encased in metamorphic rocks that record less focused magmatism. The percentage of igneous rocks increases systematically from shallow to middle to deep levels; from approximately 37% to 55% to 65% of the total rock volume. Unfocused magmas comprise much higher percentages (approximately 19%) of the total plutonic rock at deep- and mid-crustal depths, but only 1% at shallower levels, whereas the largest intrusions were emplaced into shallow crust. Plutons have a range of shapes, including: asymmetric wedges to funnels; subhorizontal tabular sheets; steep-sided, blade-shaped bodies with high aspect ratios in map view; and steep-sided, vertically extensive (> 8 km) bodies shaped like thick disks and/or hockey pucks. Sheeted intrusions and gently dipping tabular bodies are more common with depth. Some of these plutons fit the model that most intrusions are subhorizontal and tabular, but many do not, reflecting the complex changes in lithology and rheology in arc crust undergoing regional shortening. The steep sheeted plutons partly represent magma transfer zones that fed the large shallow plutons, which were sites of intermittent

  15. Ultra-Compact Motor Controller

    NASA Technical Reports Server (NTRS)

    Townsend, William T.; Crowell, Adam; Hauptman, Traveler; Pratt, Gill Andrews

    2012-01-01

    This invention is an electronically commutated brushless motor controller that incorporates Hall-array sensing in a small, 42-gram package that provides 4096 absolute counts per motor revolution position sensing. The unit is the size of a miniature hockey puck, and is a 44-pin male connector that provides many I/O channels, including CANbus, RS-232 communications, general-purpose analog and digital I/O (GPIO), analog and digital Hall inputs, DC power input (18-90 VDC, 0-l0 A), three-phase motor outputs, and a strain gauge amplifier. This controller replaces air cooling with conduction cooling via a high-thermal-conductivity epoxy casting. A secondary advantage of the relatively good heat conductivity that comes with ultra-small size is that temperature differences within the controller become smaller, so that it is easier to measure the hottest temperature in the controller with fewer temperature sensors, or even one temperature sensor. Another size-sensitive design feature is in the approach to electrical noise immunity. At a very small size, where conduction paths are much shorter than in conventional designs, the ground becomes essentially isopotential, and so certain (space-consuming) electrical noise control components become unnecessary, which helps make small size possible. One winding-current sensor, applied to all of the windings in fast sequence, is smaller and wastes less power than the two or more sensors conventionally used to sense and control winding currents. An unexpected benefit of using only one current sensor is that it actually improves the precision of current control by using the "same" sensors to read each of the three phases. Folding the encoder directly into the controller electronics eliminates a great deal of redundant electronics, packaging, connectors, and hook-up wiring. The reduction of wires and connectors subtracts substantial bulk and eliminates their role in behaving as EMI (electro-magnetic interference) antennas. A shared

  16. Nondestructive evaluation and assay for the plutonium ceramification test facility

    SciTech Connect

    Mitchell, M; Pugh, D; Wang, T-F

    2000-03-07

    Lawrence Livermore National Laboratory (LLNL) has conducted design and testing activities of the Nondestructive Assay/Evaluation (NDA/NDE) system that will be installed to support the Plutonium Ceramification Test Facility (PuCTF). PuCTF immobilizes plutonium using the ceramic can-in-canister technology. The overall function of the NDA/NDE System is to ensure that sintered pucks contain the appropriate materials for ceramification process control, special nuclear materials (SNM) accountability, and repository acceptance. The system accepts sample pucks from the ceramification system, performs measurements, and determines if the product pucks are acceptable. This report details the conceptual system that is being developed.

  17. Plutonium Immobilization Can Loading Conceptual Design

    SciTech Connect

    Kriikku, E.

    1999-05-13

    'The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization can loading conceptual design and includes a process block diagram, process description, preliminary equipment specifications, and several can loading issues. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.'

  18. Plutonium immobilization feed batching system concept report

    SciTech Connect

    Erickson, S.

    2000-07-19

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with high level waste glass for permanent storage. Feed batching is one of the first process steps involved with first stage plutonium immobilization. It will blend plutonium oxide powder before it is combined with other materials to make pucks. This report discusses the Plutonium Immobilization feed batching process preliminary concept, batch splitting concepts, and includes a process block diagram, concept descriptions, a preliminary equipment list, and feed batching development areas.

  19. Modeling of the jack rabbit series of experiments with a temperature based reactive burn model

    NASA Astrophysics Data System (ADS)

    Desbiens, Nicolas

    2017-01-01

    The Jack Rabbit experiments, performed by Lawrence Livermore National Laboratory, focus on detonation wave corner turning and shock desensitization. Indeed, while important for safety or charge design, the behaviour of explosives in these regimes is poorly understood. In this paper, our temperature based reactive burn model is calibrated for LX-17 and compared to the Jack Rabbit data. It is shown that our model can reproduce the corner turning and shock desensitization behaviour of four out of the five experiments.

  20. Reactive Flow Modeling of the Interaction of TATB Detonation Waves with Inert Materials

    SciTech Connect

    Tarver, C M; McGuire, E M

    2002-07-01

    The Ignition & Growth model for the shock initiation and detonation of solid explosives is applied to calculating the main features of detonation waves in the triaminotrinitrobenzene (TATB) based high explosives LX-17, PBX 9502 and EDC-35. Under detonation conditions, TATB based explosives exhibit reaction zone lengths of 2 to 3 mm depending on the interactions between the detonation wave and the surrounding inert materials. This paper describes comparisons of Ignition & Growth calculations with data from several two- and three-dimensional experiments in which various materials are used to confine the TATB based explosives. The calculated unconfined failure diameters of PBX 9502 are normalized to the measured values at five initial temperatures. Failure diameters for LX-17 are then estimated by changing only the fraction ignited near the shock front. Fabry-Perot data on spherically divergent LX-17 snowball experiments is also compared to calculations. Calculated detonation velocities, wave front curvatures, and metal acceleration velocities are compared to experimental detonation data for TATB-based high explosives in tantalum, copper, PMMA, brass, and beryllium confinement. Three-dimensional prism failure test results on PBX 9502 are also stimulated using the ALE3D code.

  1. Development of the Direct Fabrication Process for Plutonium Immobilization

    SciTech Connect

    Congdon, J.W.

    2001-07-10

    The current baseline process for fabricating pucks for the Plutonium Immobilization Program includes granulation of the milled feed prior to compaction. A direct fabrication process was demonstrated that eliminates the need for granulation.

  2. Automated, High Temperature Furnace for Glovebox Operation

    SciTech Connect

    Neikirk, K.

    2001-01-03

    The Plutonium Immobilization Project (PIP), to be located at the Savannah River Site SRS, is a combined development and testing effort by Lawrence Livermore National Laboratory (LLNL), Westinghouse Savannah River Company (WSRC), Pacific Northwest National Laboratory (PNNL), Argonne National Laboratory (ANL), and the Australian National Science and Technology Organization (ANSTO). The Plutonium Immobilization process involves the disposition of excess plutonium by incorporation into ceramic pucks. As part of the immobilization process, furnaces are needed for sintering the ceramic pucks. The furnace being developed for puck sintering is an automated, bottom loaded furnace with insulating package and resistance heating elements located within a nuclear glovebox. Other furnaces types considered for the application include retort furnaces and pusher furnaces. This paper, in part, will discuss the furnace technologies considered and furnace technology selected to support reliable puck sintering in a glovebox environment.

  3. Racial and Gender Report Card, 2003: A Comprehensive Analysis of the Hiring Practices of the National Basketball Association, National Football League, National Hockey League, Major League Baseball, Major League Soccer, Women's National Basketball Association, and NCAA and Its Member Institutions.

    ERIC Educational Resources Information Center

    Lapchick, Richard E.

    This is the 12th issue of the "Racial and Gender Report Card," which assesses hiring practices of women and people of color in U.S. professional and amateur sports and sporting organizations. It considers the composition of players, coaches, and front office/athletic department employees in the leading sports organizations. Each organization is…

  4. Automated, High Temperature Furnace for Glovebox Operation

    SciTech Connect

    Neikirk, K.

    2001-01-26

    The U.S. Department of Energy will immobilize excess plutonium in the proposed Plutonium Immobilization Plant (PIP) at the Savannah River Site (SRS) as part of a two track approach for the disposition of weapons usable plutonium. As such, the Department of Energy is funding a development and testing effort for the PIP. This effort is being performed jointly by Lawrence Livermore National Laboratory (LLNL), Westinghouse Savannah River Company (WSRC), Pacific Northwest National Laboratory (PNNL), and Argonne National Laboratory (ANL). The Plutonium Immobilization process involves the disposition of excess plutonium by incorporation into ceramic pucks. As part of the immobilization process, furnaces are needed for sintering the ceramic pucks. The furnace being developed for puck sintering is an automated, bottom loaded furnace with insulting package and resistance heating elements located within a nuclear glovebox. Other furnaces considered for the application include retort furnaces and pusher furnaces. This paper, in part, will discuss the furnace technologies considered and furnace technology selected to support reliable puck sintering in a glovebox environment. Due to the radiation levels and contamination associated with the plutonium material, the sintering process will be fully automated and contained within nuclear material gloveboxes. As such, the furnace currently under development incorporates water and air cooling to minimize heat load to the glovebox. This paper will describe the furnace equipment and systems needed to employ a fully automated puck sintering process within nuclear gloveboxes as part of the Plutonium Immobilization Plant.

  5. Free-Flying Magnetometer Data System

    NASA Technical Reports Server (NTRS)

    Blaes, B.; Javadi, H.; Spencer, H.

    2000-01-01

    The Free-Flying Magnetometer (FFM) is an autonomous "sensorcraft" developed at the Jet Propulsion Laboratory (JPL) for the Enstrophy sounding rocket mission. This mission was a collaborative project between the University of New Hampshire, Cornell University and JPL. The science goal of the mission was the study of current filamentation phenomena in the northern auroral region through multipoint measurements of magnetic field. The technical objective of the mission was the proof of concept of the JPL FFM design and the demonstration of an in-situ multipoint measurement technique employing many free-flying spacecraft. Four FFMs were successfully deployed from a sounding rocket launched from Poker Flats, Alaska on February 11, 1999. These hockey-puck-sized (80 mm diameter, 38 mm. height, 250 gram mass) free flyers each carry a miniature 3-axis flux-gate magnetometer that output +/- 2 V signals corresponding to a +/- 60,000 nT measurement range for each axis. The FFM uses a synchronized four-channel Sigma(Delta) Analog-to-Digital Converter (ADC) having a dynamic range of +/- 2.5V and converting at a rate of 279 samples/second/channel. Three channels are used to digitize the magnetometer signals to 17-bit (1.144 nT/bit) resolution. The fourth ADC channel is multiplexed for system monitoring of four temperature sensors and two battery voltages. The FFM also contains two sun sensors, a laser diode which emits a fan-shaped beam, a miniature S-band transmitter for direct communication to the ground station antennas, an ultra-stable Temperature Compensated Crystal Oscillator (TCXO) clock, an integrated data subsystem implemented in a Field-Programmable Gate Array (FPGA), a 4 Mbit Static Random Access Memory (SRAM) for data storage and Lithium Thionyl Chloride batteries for power. Communicating commands to the FFM prior to deployment is achieved with an infrared (IR) link. The FFM IR receiver responds to 9-bit pulse coded signals that are generated by an IR Light Emitting

  6. Jack Rabbit Pretest 2021E PT6 Photonic Doppler Velocimetry Data Volume 6 Section 1

    SciTech Connect

    Hart, M M; Strand, O T; Bosson, S T; Bonner, R A; Hester, D M

    2008-06-25

    The Jack Rabbit Pretest (PT) 2021E PT6 experiment was fired on April 1, 2008 at the Contained Firing Facility, Site 300, Lawrence Livermore National Laboratory. This experiment is part of an effort to determine the properties of LX-17 in a regime where corner-turning behavior and dead-zone formation are not well understood. Photonic Doppler Velocimetry (PDV) measured diagnostic plate velocities confirming the presence of a persistent LX-17 dead-zone formation and the resultant impulse gradient applied under the diagnostic plate. The Jack Rabbit Pretest 2021E PT6, 160 millimeter diameter experiment returned data on all eight PDV probes. The probes measured on the central axis and at 20, 30, 35, 45, 55, 65, 75 millimeters from the central axis. The experiment was shot at an ambient room temperature of 65 degrees Fahrenheit. The earliest PDV signal extinction was 54.2 microseconds at 30 millimeters. The latest PDV signal extinction time was 64.5 microseconds at the central axis. The measured velocity ranged from meters per second to thousands of meters per second. First detonation wave induced jump-off was measured at 55 millimeters at 14.1 microseconds. The PDV data provided an unambiguous indication of dead-zone formation and an impulse gradient applied to the diagnostic plate. The central axis had a last measured velocity of 1860 meters per second. At 55 millimeters the last measured velocity was 2408 meters per second. The low-to-high velocity ratio was 0.77. Velocity data was integrated to compute diagnostic plate cross section profiles. Velocity data was differentiated to compute a peak pressure under the diagnostic plate at the central axis of 227 kilobars at 20.1 microseconds, indicating a late time chemical reaction in the LX-17 dead-zone. Substantial motion (>1 m/s) of the diagnostic plate over the dead-zone is followed by detonation region motion within approximately 1.7 microseconds.

  7. Detonator cable initiation system safety investigation: Consequences of energizing the detonator and actuator cables

    SciTech Connect

    Osher, J.; Chau, H.; Von Holle, W.

    1994-03-01

    This study was performed to explore and assess the worst-case response of a W89-type weapons system, damaged so as to expose detonator and/or detonator safing strong link (DSSL) cables to the most extreme, credible lightning-discharge, environment. The test program used extremely high-current-level, fast-rise-time (1- to 2-{mu}s) discharges to simulate lightning strikes to either the exposed detonator or DSSL cables. Discharges with peak currents above 700 kA were required to explode test sections of detonator cable and launch a flyer fast enough potentially to detonate weapon high explosive (HE). Detonator-safing-strong-link (DSSL) cables were exploded in direct contact with hot LX-17 and Ultrafine TATB (UFTATB). At maximum charging voltage, the discharge system associated with the HE firing chamber exploded the cables at more than 600-kA peak current; however, neither LX-17 nor UFTATB detonated at 250{degree}C. Tests showed that intense surface arc discharges of more than 700 kA/cm in width across the surface of hot UFTATB [generally the more sensitive of the two insensitive high explosives (IHE)] could not initiate this hot IHE. As an extension to this study, we applied the same technique to test sections of the much-narrower but thicker-cover-layer W87 detonator cable. These tests were performed at the same initial stored electrical energy as that used for the W89 study. Because of the narrower cable conductor in the W87 cables, discharges greater than 550-kA peak current were sufficient to explode the cable and launch a fast flyer. In summary, we found that lightning strikes to exposed DSSL cables cannot directly detonate LX-17 or UFTATB even at high temperatures, and they pose no HE safety threat.

  8. Bigplate: an oblique angle explosive EOS test

    SciTech Connect

    Anderson, S; Avara, R; Fried, L; Janzen, J; McGuire, E; Souers, P C; Wu, B

    1998-04-16

    Bigplate is an advanced explosive equation of state (EOS) test. It consists of a point detonator driving a large disc (100 mm radius) of explosive, which pushes a 0.5 mm thick copper or tantalum plate. The plate is observed by a five-beam Fabry-Perot interferometer, which has beams at 0, 10, 20,40 and 80 mm on the plate. A short Fabry gives the jump-off to high accuracy; a long Fabry runs out to I0-15 microsec. A detailed error analysis is given, with the final velocity measurements considered good to ±0.066 mm/microsec. Jump-offs are measured to 0.01-0.02 microsec. Spall is seen in all shots, which creates a time delay on both the first and second velocity plateaus. A 0.1 microsec delay in jump-off of unknown origin is also seen at 80 mm. In order of decreasing explosive ideality, the explosives tired have been LX-14, LX-04 and LX-17. To partially negate the time delays, the data and code runs are overlaid at each radial position between the first and second plateaus. Traditional JWL's model LX-14 and LX-04 within accuracy, but not so for LX-17. The spall may be partly modeled using the pmin model but high resolution zoning is required. At longer times, spall does not appear to affect the explosive energetics. Because it includes diagonal zone crossing, Bigplate occupies a location between simple plate and cylinder tests and truly complex geometries. Hence, an EOS that fails Bigplate is not likely to move on to more complex issues. Bigplate is an excellent test bed for radically new EOS's, and the initial LX-17 runs done with Equilibrium and KINETIC CHEETAH are promising.

  9. Nontraditional Games in a Foreign Environment.

    ERIC Educational Resources Information Center

    Cross, Thomas S.

    A study investigated students' reactions to the addition of nontraditional games (played in and traditional to another country) to the physical education curriculum. Seventh grade students in Australia were introduced to game development, skills, and present status of two sports, 'Midget' Hockey, a modified version of Canadian ice hockey, and…

  10. The Effect of Role Ambiguity on Competitive State Anxiety.

    ERIC Educational Resources Information Center

    Beauchamp, Mark R.; Bray, Steven R.; Eys, Mark A.; Carron, Albert V.

    2003-01-01

    Investigated the relationship between role ambiguity and precompetition state anxiety among high school athletes playing field hockey. Surveys of male and female field hockey players in the United Kingdom indicated that ambiguity concerning the scope of one's offensive responsibilities was predictive cognitive state anxiety, while ambiguity…

  11. Skill Acquisition in Students with and without Pervasive Developmental Disorder

    ERIC Educational Resources Information Center

    Hutzler, Yeshayahu; Margalit, Matan

    2009-01-01

    The purposes of this study were (a) to examine skill acquisition in field hockey of seven junior-high school students with PDD, who attended an inclusive class; and (b) to compare the degree of skill acquisition in field hockey of junior-high school students without disabilities who attend an inclusive class and those who attend a regular class.…

  12. Beliefs about Gender Appropriateness, Ability, and Competence in Physical Activity.

    ERIC Educational Resources Information Center

    Solmon, Melinda A.; Lee, Amelia M.; Belcher, Doland; Harrison, Louis, Jr.; Wells, Lori

    2003-01-01

    Used self-efficacy theory as a framework to investigate the interaction of beliefs about gender appropriateness and conceptions of ability on competence beliefs in physical activity. College students completed surveys about the sport of hockey, watched a video of a specific hockey skill, and responded to questions about the skill. Results support…

  13. Safety in Team Sports. Sports Safety Series, Monograph No. 3.

    ERIC Educational Resources Information Center

    Borozne, Joseph, Ed.; And Others

    This monograph examines methods of promoting safe practices in the conduct of selected team sports with the aim of reducing and eliminating the occurrance of injuries. The team sports discussed are baseball and softball, basketball, field hockey, tackle football, touch and flag football, ice hockey, lacrosse, and soccer. (MJB)

  14. Score a Facilities Hat Trick: Strategic Goals for Successful Hiring, Training, and Team Commitment

    ERIC Educational Resources Information Center

    Loy, Darcy

    2012-01-01

    Granted, it might be a bit of a stretch to find comparable attributes between an ice hockey team and facilities management organizations. However, if you are open-minded to the possibility and begin to analyze each of these entities, you will find there are some distinct similarities. Ice hockey is a fast-paced and ever-changing game, much like a…

  15. Noise and Attentional Selectivity: A Reproducible Phenomenon?

    ERIC Educational Resources Information Center

    Forster, Peter M.; Grierson, Arthur T.

    1978-01-01

    Four pursuit-tracking experiments were conducted in an attempt to replicate with adults, Hockey's findings that loud noise increases attentional selectivity. Neither attentional selectivity nor masking of auditory feedback was found to be significant. For Hockey's reply and the authors' rejoinder, see p499-506 of this issue. (SJL)

  16. Equation of state of insensitive high explosives

    SciTech Connect

    Ree, F H; Van Thiel, M; Viecelli, J A

    1998-08-12

    Detonation of an insensitive high explosive formulated with a fluorine containing binder produces a large amount of condensed carbon and gaseous HF product, which transforms into CF{sub 4} as the pressure is increased. The former (carbon condensation) is characterized by slow energy release, while the latter (HF) has no shockwave data. We have identified that these two items are the key factors, which make reliable prediction of the performance of an insensitive high explosive very difficult. This paper describes physical models to address these issues and apply the models to analyze experimental data of LX-17.

  17. Insensitive fuze train for high explosives

    SciTech Connect

    Cutting, Jack L.; Lee, Ronald S.; Von Holle, William G.

    1994-01-01

    A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124.

  18. Insensitive fuze train for high explosives

    SciTech Connect

    Cutting, J.L.; Lee, R.S.; Von Holle, W.G.

    1994-01-04

    A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124 is described. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124. 3 figures.

  19. Plutonium immobilization ceramic feed batching component test report

    SciTech Connect

    Erickson, S.A.

    1999-10-04

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with high level waste glass for permanent storage. Ceramic feed batching (CFB) is one of the first process steps involved with first stage plutonium immobilization. The CFB step will blend plutonium oxide powder before it is combined with other materials to make pucks. This report discusses the Plutonium Immobilization CFB process preliminary concept (including a process block diagram), batch splitting component test results, CFB development areas, and FY 1999 and 2000 CFB program milestones.

  20. Plutonium Immobilization Can Loading Concepts

    SciTech Connect

    Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.; Rogers, L.; Fiscus, J.; Dyches, G.

    1998-05-01

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses five can loading conceptual designs and the lists the advantages and disadvantages for each concept. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas. The can loading welder and cutter are very similar to the existing Savannah River Site (SRS) FB-Line bagless transfer welder and cutter and thus they are a low priority development item.

  1. Deep drawing of uranium metal

    SciTech Connect

    Jackson, R J; Lundberg, M R

    1987-01-19

    A procedure was developed to fabricate uranium forming blanks with high ''draw-ability'' so that cup shapes could be easily and uniformly deep drawn. The overall procedure involved a posttreatment to develop optimum mechanical and structural properties in the deep-drawn cups. The fabrication sequence is casting high-purity logs, pucking cast logs, cross-rolling pucks to forming blanks, annealing and outgassing forming blanks, cold deep drawing to hemispherical shapes, and stress relieving, outgassing, and annealing deep-drawn parts to restore ductility and impart dimensional stability. The fabrication development and the resulting fabrication procedure are discussed in detail. The mechanical properties and microstructural properties are discussed.

  2. Plutonium Immobilization Can Loading Conceptual Design for 13 MT Case

    SciTech Connect

    Peterson, K.D.

    2001-01-31

    The Plutonium Immobilization Plant (PIP) will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization Can Loading conceptual design for the 13 Metric Ton (MT) PIP throughput case. This report includes a process block diagram, process description, and preliminary equipment specifications and documents the changes to the original can loading concept documented in previous reports.

  3. Plutonium Immobilization Can Loading FY98 Year End Design Report

    SciTech Connect

    Kriikku, E.

    1998-11-25

    The Plutonium Immobilization Facility will immobilize plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report summarizes FY98 Can Loading work completed for the Plutonium Immobilization Project and it includes summaries of reports on Can Size, Equipment Review, Preliminary Concepts, Conceptual Design, and Preliminary Specification. Plant trip reports for the Greenville Automation and Manufacturing Exposition, Rocky Flats BNFL Pu repackaging glovebox line, and vendor trips are also included.

  4. Modeling the kinetics of carbon coagulation in explosives detonation

    NASA Astrophysics Data System (ADS)

    Ree, F. H.; Viecelli, J. A.; Glosli, J. N.

    1998-05-01

    A typical insensitive high explosive such as LX-17 has a large carbon content. The detonation behavior of these explosives is affected by a slow coagulation of carbon atoms by diffusion and their possible transformation from one chemical bonding type to another. We have used the Brenner bond order potential to compute the melting line of diamond at high pressure and high temperature by molecular dynamics and Monte Carlo simulations, with the goal to refine the potential for the study of the kinetics of the graphite diamond transition. The slow diffusion-controlled kinetics of carbon clusters has been examined by including a time-dependent surface correction to the Gibbs free energy of these clusters in the nonequilibrium CHEQ code. We also propose a new explosive burn model which incorporates a partial release of the heat of detonation in a fast reaction zone, followed by a diffusion-limited release of the remaining energy. Hydrodynamic applications of the new burn model to LX-17 show that computed expansion and compression results both agree closely with experimental data.

  5. Comprehensive Characterization of Voids and Microstructure in TATB-based Explosives from 10 nm to 1 cm: Effects of Temperature Cycling and Compressive Creep

    SciTech Connect

    Willey, T M; Lauderbach, L; Gagliardi, F; Cunningham, B; Lorenz, K T; Lee, J I; van Buuren, T; Call, R; Landt, L; Overturf, G

    2010-02-26

    This paper outlines the characterization of voids and Microstructure in TATB-based Explosives over several orders of magnitude, from sizes on the order of 10 nm to about 1 cm. This is accomplished using ultra small angle x-ray scattering to investigate voids from a few nm to a few microns, ultra small angle neutron scattering for voids from 100 nm to 10 microns, and x-ray computed microtomography to investigate microstructure from a few microns to a few centimeters. The void distributions of LX-17 are outlined, and the microstructure of LX-17 is presented. Temperature cycling and compressive creep cause drastically different damage to the microstructure. Temperature cycling leads to a volume expansion (ratchet growth) in TATB-based explosives, and x-ray scattering techniques that are sensitive to sizes up to a few microns indicated changes to the void volume distribution that had previously accounted for most, but not all of the change in density. This paper presents the microstructural damage larger than a few microns caused by ratchet growth. Temperature cycling leads to void creation in the binder poor regions associated with the interior portion of formulated prills. Conversely, compressive creep causes characteristically different changes to microstructure; fissures form at binder-rich prill boundaries prior to mechanical failure.

  6. Probabilistic Threshold Criterion

    SciTech Connect

    Gresshoff, M; Hrousis, C A

    2010-03-09

    The Probabilistic Shock Threshold Criterion (PSTC) Project at LLNL develops phenomenological criteria for estimating safety or performance margin on high explosive (HE) initiation in the shock initiation regime, creating tools for safety assessment and design of initiation systems and HE trains in general. Until recently, there has been little foundation for probabilistic assessment of HE initiation scenarios. This work attempts to use probabilistic information that is available from both historic and ongoing tests to develop a basis for such assessment. Current PSTC approaches start with the functional form of the James Initiation Criterion as a backbone, and generalize to include varying areas of initiation and provide a probabilistic response based on test data for 1.8 g/cc (Ultrafine) 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and LX-17 (92.5% TATB, 7.5% Kel-F 800 binder). Application of the PSTC methodology is presented investigating the safety and performance of a flying plate detonator and the margin of an Ultrafine TATB booster initiating LX-17.

  7. Discrepant Results in a 2-D Marble Collision

    ERIC Educational Resources Information Center

    Kalajian, Peter

    2013-01-01

    Video analysis of 2-D collisions is an excellent way to investigate conservation of linear momentum. The often-desired experimental design goal is to minimize the momentum loss in order to demonstrate the conservation law. An air table with colliding pucks is an ideal medium for this experiment, but such equipment is beyond the budget of many…

  8. A Preponderance of Elastic Properties of Alpha Plutonium Measured Via Resonant Ultrasound Spectroscopy

    SciTech Connect

    Saleh, Tarik A.; Farrow, Adam M.; Freibert, Franz J.

    2012-06-06

    Samples of {alpha} plutonium were fabricated at the Los Alamos National Laboratory's Plutonium Facility. Cylindrical samples were machined from cast pucks. Precision immersion density and resonant ultrasound spectroscopy (RUS) measurements were completed on 27 new samples, yielding elastic moduli measurements. Mechanical tests were performed in compression yielding stress-strain curves as a function of rate, temperature and phase.

  9. Physics Notes

    ERIC Educational Resources Information Center

    School Science Review, 1972

    1972-01-01

    Short articles describe the use of a lever to transfer energy between pucks on a frictionless surface, a demonstration of the principle of conservation of linear momentum, the construction of an inexpensive joulemeter, the design and construction of a simple logic demonstration board using integrated circuits, mounting of Geiger-counters to…

  10. Apparatus for Teaching Physics.

    ERIC Educational Resources Information Center

    Gottlieb, Herbert H., Ed.

    1980-01-01

    Summarizes the advantages in using the Daedalon Air Table, which supplies compressed air to the pucks instead of the table surface itself. Describes methods for constructing an electronic null detector using a Weston type galvanometer and an integrated circuit operational amplifier. Also describes a redesigned and improved sound-level meter. (CS)

  11. Condensed and Enriched: Images of the Miniature and of the World of Children's Literature.

    ERIC Educational Resources Information Center

    Hancock, Susan

    Research into the portrayal of miniature human-like characters in the fictional narratives of art and literature suggests that profound values abound in the miniature. The paper discusses two examples of fairy miniatures, Rudyard Kipling's "Puck" and J. M. Barrie's "Tinker Bell." Little characters, whatever their provenance,…

  12. A Bibliography of the Physical Oceanography of Straits.

    DTIC Science & Technology

    1986-11-01

    Kelley (eds.), Univer- description of currents in the Glebinka Strait in Puck sity of Alaska, Fairbanks, pp. 3-37. Bay (Poland). Oceanografia , Gdansk 5...3742. Archivio di Oceanografia E Limnologia 19:65-82. Whitworth, T. and R. G. Peterson (1985). Volume Waldichuk, M. (1957). Physical oceanography of

  13. Missouri Assessment Program (MAP), Spring 1999: Intermediate Communication Arts, Released Items, Grade 7.

    ERIC Educational Resources Information Center

    Missouri State Dept. of Elementary and Secondary Education, Jefferson City.

    This document deals with testing in intermediate communication arts for seventh graders in Missouri public schools. The document contains the following items from the Test Booklet: "Under the Rice Moon" (Rhiannon Puck); "Dogspirit" (Gary Paulsen) (Session 1, Items 4, 5, 6, and 8); a writing prompt; and a writer's checklist. It…

  14. Incremental Sampling Methodology (ISM) for Metallic Residues

    DTIC Science & Technology

    2013-08-01

    metallic puck mills constructed of agate are also available. Presently, though, the agate bowls are a third of the size of the metal bowls , thus...2 mm and greater than 2 mm) are weighed. The less-than-2-mm sieved fraction is mechanically milled (e.g., within a hood for dust control) using an

  15. Development of the Molecular Adsorber Coating for Spacecraft and Instrument Interiors

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin

    2011-01-01

    On-orbit Molecular Contamination occurs when materials outgas and deposit onto very sensitive interior surfaces of the spacecraft and instruments. The current solution, Molecular Adsorber Pucks, has disadvantages, which are reviewed. A new innovative solution, Molecular Adsorber Coating (MAC), is currently being formulated, optimized, and tested. It is a sprayable alternative composed of Zeolite-based coating with adsorbing properties.

  16. Shopping for Science.

    ERIC Educational Resources Information Center

    Ward, John; And Others

    1992-01-01

    Describes inexpensive science materials for doing science activities using the steps in the learning cycle: engage, explore, explain, extend, and evaluate. The hands-on activities help students construct knowledge of dissolving and filtering, chemical reactions, conductivity of metals, heat absorption, motion (frictionless puck), sound production…

  17. Effects of the Advanced Combat Helmet (ACH) and Selected Communication and Hearing Protection Systems (C&HPSs) on Speech Communication: Talk-Through Systems

    DTIC Science & Technology

    2007-04-01

    1 bat bad back bass ban bath 2 bean beach beat beam bead beak 3 bub bus but buff buck bug 4 came cape cane cake cave case 5 cut...15 peace peas peak peal peat peach 16 pill pick pip pig pin pit 17 pun puff pup puck pus pub 18 rave rake race rate raze ray 19 sake sale save

  18. Techniques for Teachers Section

    ERIC Educational Resources Information Center

    Tait, A., Ed.

    1973-01-01

    Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

  19. Plutonium Immobilization Can Loading Preliminary Specifications

    SciTech Connect

    Kriikku, E.

    1998-11-25

    This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.

  20. Cold, Ice, and Snow Safety (For Parents)

    MedlinePlus

    ... be outdoors for a while. previous continue Winter Sports Safety If your kids decide to go sledding ... safety smarts, too. Make sure your kids avoid sports injuries by wearing helmets during ice hockey games ...

  1. 21 CFR 1140.16 - Conditions of manufacture, sale, and distribution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... retailer may distribute or cause to be distributed any free samples of smokeless tobacco: (i) To a sports team or entertainment group; or (ii) At any football, basketball, baseball, soccer, or hockey event...

  2. How to Succeed in Business.

    ERIC Educational Resources Information Center

    Arnold, Josh

    1996-01-01

    Entrepreneurship is helping balance the budget for the Gloucester, Massachusetts, schools. The school district has taken over management of an indoor ice hockey rink, is running concessions on two city beaches, and started its own school bus company. (MLF)

  3. Sports and Recreation Are a Rising Cause of Spinal Cord Injury.

    ERIC Educational Resources Information Center

    Tator, Charles H.; Edmonds, Virginia E.

    1986-01-01

    Sports and recreation rose from the third to the second leading cause of spinal injuries treated in two Toronto hospitals between 1948 and 1983. Separate surveys of diving and hockey injuries are also reported. (Author/MT)

  4. Safety Tips: Baseball (For Parents)

    MedlinePlus

    ... by U.S.A. Little League and the American Sports Medicine Institute: 7-8 years old: 50 pitches a ... ON THIS TOPIC Signing Kids Up for Sports Sports Medicine Center Safety Tips: Hockey Safety Tips: Basketball Competitive ...

  5. BIG PLAY. Hospitals team up with biggest names in pro sports to score brand awareness.

    PubMed

    Robeznieks, Andis

    2016-07-01

    Partnering with major league baseball, basketball, hockey, football and even lacrosse teams isn't just about building brand recognition. It's also a way to promote health and fitness in the community.

  6. New Names for New Games

    ERIC Educational Resources Information Center

    Foster, Jerry; and others

    1969-01-01

    A collection of the following original games, adapted from traditional sports: frisbee baseball, rollerboard hockey, bell ball, throw and go netball, boardless basketball, crosseball, flag football, french dodgeball, korfbal, german bat ball, and flag football. (AP)

  7. EPA Recognizes Dallas Stars for Reducing Food Waste

    EPA Pesticide Factsheets

    DALLAS - (Jan. 29, 2015) The U.S. Environmental Protection Agency (EPA) recently recognized the Dallas Stars of the National Hockey League for the team's achievements in reducing food waste. The Stars participated in EPA's Food Recovery Challenge, w

  8. Ice Skating Instruction at the University of Illinois.

    ERIC Educational Resources Information Center

    Christensen, Char; And Others

    1981-01-01

    The University of Illinois at Urbana-Champaign conducts a instructional ice skating program for its students and the community. Activities include: a figure skating club; a speed skating club; ice hockey program; and ice skating classes. (CJ)

  9. Broken Nose

    MedlinePlus

    ... include contact sports, physical fights, falls and motor vehicle accidents that result in facial trauma. A broken ... such as football or hockey Physical altercations Motor vehicle accidents Falls A broken nose can even be ...

  10. Sports betting: can gamblers beat randomness?

    PubMed

    Cantinotti, Michael; Ladouceur, Robert; Jacques, Christian

    2004-06-01

    Although skills are not considered relevant in chance-governed activities, only a few studies have assessed the extent to which sport expert skills in wagering are a manifestation of the illusion of control. This study examined (a) whether expert hockey bettors could make better predictions than chance, (b) whether expert hockey bettors could achieve greater monetary gains than chance, and (c) what kind of strategies hockey gamblers rely on when betting. Accordingly, 30 participants were asked to report their state lottery hockey bets on 6 occasions. We suggest that the information used by bettors, along with near-misses, reinforces their perception of expertise. The results of this experiment suggest that the so-called "skills" of the sports bettors are cognitive distortions.

  11. Concussions in the NHL: A narrative review of the literature.

    PubMed

    Izraelski, Jason

    2014-12-01

    Ice hockey has been identified as a sport with a high risk for concussions. Given the health sequelae associated with the injury, a great deal of attention has been placed on its diagnosis, management and return-to-play protocols. The highest level of ice hockey in North America is played in the National Hockey League (NHL), and concussions pose a serious threat to the health of the players and the game itself. Unfortunately, the scientific literature on concussions in ice hockey is derived mostly from research conducted on youth and amateur levels of play, leaving a gap in our knowledge at the professional level. This narrative review attempts to summarize what is known about concussion incidence, mechanisms of injury and risk factors in the NHL.

  12. Concussion in Winter Sports

    MedlinePlus

    ... why CDC and the NFL teamed up with USA Hockey, the US Ski and Snowboarding Association, and ... FOIA Accessibility Privacy No FEAR Act Inspector General USA.gov Contact CDC Centers for Disease Control and ...

  13. Medial Collateral Ligament (MCL) Injuries

    MedlinePlus

    ... torn MCL tend to play contact sports, like football and soccer. More severe injuries happen when the ... the things you love — like running or playing football, field hockey, or softball — can be frustrating. If ...

  14. TARANTULA 2011 in JWL++

    SciTech Connect

    Souers, P C; Haylett, D; Vitello, P

    2011-10-27

    Using square zoning, the 2011 version of the kinetic package Tarantula matches cylinder data, cylinder dead zones, and cylinder failure with the same settings for the first time. The key is the use of maximum pressure rather than instantaneous pressure. Runs are at 40, 200 and 360 z/cm using JWL++ as the host model. The model also does run-to-detonation, thin-pulse initiation with a P-t curve and air gap crossing, all in cylindrical geometry. Two sizes of MSAD/LX-10/LX-17 snowballs work somewhat with these settings, but are too weak, so that divergent detonation is a challenge for the future. Butterfly meshes are considered but do not appear to solve the issue.

  15. GAUGE RUN-TO-DETONATION DATA AND FAILURE/DEAD ZONE MODELING

    SciTech Connect

    Souers, P C; Vitello, P; Vandersall, K S

    2009-06-26

    Previous shock initiation run-to-detonation experiments on energetic materials were plotted with distance and time to get a single distance/time to detonation. Modern shots utilize enough gauges so that the distance-time data can be differentiated, which shows not only the usual inflection pressure point before detonation, referred to here as P{sub b}, but also a second, low-pressure inflection, referred to here as P{sub a}, that marks rapid ramp-up of the initiation. An analysis of the TATB based LX-17 and PBX 9502 in addition to the LLM-105 based RX-55 data shows that both P{sub a} and P{sub b} increase linearly with the initiation pressure created by the flyer plate. This contradicts the current method in the Tarantula failure/dead zone model, which uses constant pressure boundaries between reaction regions. Modeling changes required by the new data will be considered.

  16. Cook-off resistant initiation trains

    SciTech Connect

    Cutting, J.L.; Nichols, A.L. III; von Holle, W.G.; Lee, R.S.

    1992-03-26

    We have developed and tested initiation trains which are designed to withstand abnormal thermal environments. The design philosophy is to use a slapper detonator to initiate a small quantity of initiating explosive, whose mass is too small to permit a transition to detonation in a cook-off environment. We have successfully used PETN and HNS as the initiating explosive. The detonation of the initiating explosive drives a thin metal flyer plate onto an ultrafine-particle-size TATB booster which, in turn, initiates a main charge. The booster can be scaled to almost any size without compromising the cook-off resistance by using the ultrafine TATB to initiate a larger charge of LX-17 insensitive explosive as a secondary booster.

  17. The unusual stability of TATB (1,3,5-triamino-2,4,6-trinitrobenzene): A review of the scientific literature

    SciTech Connect

    Rice, S.F.; Simpson, R.L.

    1990-07-04

    This review is intended as an up-to-date review of the scientific literature on TATB since its discovery as a high explosive. In particular, it focuses on clarifying our current understanding of the relationship between the structure of TATB and its unique thermal stability. We review a large number of different publications by many authors. A small portion of the work on TATB'' presented actually consists of experimental studies on TATB formulated as PBX-9502 or as LX-17. Where relevant, this distinction is indicated. However, inasmuch as this review focuses on thermal response and the relationship of chemical reactivity to the molecular and lattice structure of TATB as a pure material, results from these other formulations may not be directly applicable, and in general we have omitted them. 4 refs.

  18. Energetic materials destruction using molten salt

    SciTech Connect

    Upadhye, R.S.; Watkins, B.E.; Pruneda, C.O.; Brummond, W.A.

    1994-04-29

    The Lawrence Livermore National Laboratory in conjunction with the Energetic Materials Center is developing methods for the safe and environmentally sound destruction of explosives and propellants as a part of the Laboratory`s ancillary demilitarization mission. LLNL has built a small-scale unit to test the destruction of HE using the Molten Salt Destruction (MSD) Process. In addition to the high explosive HMX, destruction has been carried out on RDX, PETN, ammonium picrate, TNT, nitroguanadine, and TATB. Also destroyed was a liquid gun propellant comprising hydroxyammonium nitrate, triethanolammonium nitrate and water. In addition to these pure components, destruction has been carried out on a number of commonly used formulations, such as LX-10, LX-16, LX-17, and PBX-9404.

  19. A Literature Review of Shock Sensitivity Changes of TATB Due to Thermal Cycling

    SciTech Connect

    Ritter, Boyd

    2016-07-15

    Insensitive high explosives (IHEs) based on 1,3,5-triamino 2,4,6-trinitro-benzene (TATB) are the IHEs of choice for use in nuclear warheads over conventional high explosives when safety is the only consideration, because they are very insensitive to thermal or mechanical initiation stimuli. It is this inherent insensitivity to high temperatures, shock, and impact, which provides detonation design challenges when designing TATB explosive systems while at the same time providing a significant level of protection against accidental initiation. Although classified as IHE, over the past few years the focus on explosive safety has demonstrated that the shock sensitivity of TATB is influenced with respect to temperature. A number of studies have been performed on TATB and TATB formulations, plastic bonded explosives (PBX) 9502, and LX-17-01 (LX-17), which demonstrates the increase in shock sensitivity of the explosive after it has been preheated or thermally cycled over various temperature ranges. Many studies suggest the change in sensitivity is partly due to the decomposition rates of the temperature elevated TATB. Others point to the coefficient of thermal expansion, the crystalline structures of TATB and/or the combination of all factors, which create voids which can become active hot spots. During thermal cycling, TATB is known to undergo an irreversible increase in specific volume called ratchet growth. This increase in specific volume correlates to a decrease in density. This decrease in density and increase in volume, demonstrate the creations of additional void spaces which could serve as potential new initiation hot spots thus, increasing the overall sensitivity of the HE. This literature review evaluates the published works to understand why the shock sensitivity of TATB-based plastic bonded explosives (PBXs) changes with temperature.

  20. On the violence of thermal explosion in solid explosives

    SciTech Connect

    Chidester, S.K.; Tarver, C.M.; Green, L.G.; Urtiew, P.A.

    1997-07-01

    Heavily confined cylinders of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and triaminotrinitrobenzene (TATB) were heated at rates varying from 2 C/min to 3.3 C/h. Fourteen of the cylinders were hollow, and inner metallic liners with small heaters attached were used to produce uniform temperatures just prior to explosion. A complex thermocouple pattern was used to measure the temperature history throughout the charge and to determine the approximate location where the runaway exothermic reaction first occurred. The violence of the resulting explosion was measured using velocity pin arrays placed inside and outside of the metal confinement cylinders, flash x-rays, overpressure gauges, and fragment collection techniques. Five cylinders were intentionally detonated for violence comparisons. The measured temperature histories, times to explosion, and the locations of first reaction agreed closely with those calculated by a two-dimensional heat transfer code using multistep chemical decomposition models. The acceleration of the confining metal cylinders by the explosion process was accurately simulated using a two-dimensional pressure dependent deflagration reactive flow hydrodynamic mode. The most violent HMX thermal explosions gradually accelerated their outer cases to velocities approaching those of intentional detonations approximately 120 {micro}m after the onset of explosion. The measured inner cylinder collapse velocities from thermal explosions were considerably lower than those produced by detonations. In contrast to the HMX thermal reactions, no violent thermal explosions were produced by the TATB-based explosive LX-17. A heavily confined, slowly heated LX-17 test produced sufficient pressure to cause a 0.1 cm bend in a 2 cm thick steel plate.

  1. Jack Rabbit Pretest 2021E PT4 Photonic Doppler Velocimetry Data Volume 4 Section 1

    SciTech Connect

    Hart, M M; Strand, O T; Bosson, S T; Bonner, R A; Hester, D M

    2008-06-25

    The Jack Rabbit Pretest (PT) 2021E PT4 was fired on March 19, 2008 at the Contained Firing Facility, Site 300, Lawrence Livermore National Laboratory. This experiment is part of an effort to determine the properties of LX-17 in a regime where corner-turning behavior and dead-zone formation are not well understood. Photonic Doppler Velocimetry (PDV) measured diagnostic plate velocities confirming the presence of a persistent LX-17 dead-zone formation and the resultant impulse gradient applied under the diagnostic plate. The Jack Rabbit Pretest 2021E PT4, 120 millimeter diameter experiment returned data on all eight PDV probes. The probes measured on the central axis and at 10, 20, 25, 30, 35, 40, 50 millimeters from the central axis. The experiment was shot at an ambient room temperature of 64 degrees Fahrenheit. The earliest PDV signal extinction was 44.9 microseconds at 30 millimeters. The latest PDV signal extinction time was 69.5 microseconds at 10 millimeters. The measured velocity ranged from meters per second to thousands of meters per second. First detonation wave induced jump-off was measured at 50 millimeters at 13.3 microseconds. The PDV data provided an unambiguous indication of dead-zone formation and an impulse gradient applied to the diagnostic plate. The central axis had a last measured velocity of 1558 meters per second. At 40 millimeters the last measured velocity was 2019 meters per second. The low-to-high velocity ratio was 0.77. Velocity data was integrated to compute diagnostic plate cross section profiles. Velocity data was differentiated to compute a peak pressure under the diagnostic plate at the central axis of 98.6 kilobars at 15.0 microseconds. Substantial motion (>1 m/s) of the diagnostic plate over the dead-zone is followed by detonation region motion within approximately 0.7 microseconds.

  2. Jack Rabbit Pretest 2021E PT5 Photonic Doppler Velocimetry Data Volume 5 Section 1

    SciTech Connect

    Hart, M M; Strand, O T; Bosson, S T; Bonner, R A; Hester, D M

    2008-06-25

    The Jack Rabbit Pretest (PT) 2021E PT5 was fired on March 17, 2008 at the Contained Firing Facility, Site 300, Lawrence Livermore National Laboratory. This experiment is part of an effort to determine the properties of LX-17 in a regime where corner-turning behavior and dead-zone formation are not well understood. Photonic Doppler Velocimetry (PDV) measured diagnostic plate velocities confirming the presence of a persistent LX-17 dead-zone formation and the resultant impulse gradient applied under the diagnostic plate. The Jack Rabbit Pretest 2021E PT5, 160 millimeter diameter experiment returned data on all eight PDV probes. The probes measured on the central axis and at 20, 30, 35, 45, 55, 65, 75 millimeters from the central axis. The experiment was shot at an ambient room temperature of 65 degrees Fahrenheit. The earliest PDV signal extinction was 40.0 microseconds at 45 millimeters. The latest PDV signal extinction time was 64.9 microseconds at 20 millimeters. The measured velocity ranged from meters per second to thousands of meters per second. First detonation wave induced jump-off was measured at 55 millimeters at 12.8 microseconds. The PDV data provided an unambiguous indication of dead-zone formation and an impulse gradient applied to the diagnostic plate. The central axis had a last measured velocity of 1877 meters per second. At 65 millimeters the last measured velocity was 2277 meters per second. The low-to-high velocity ratio was 0.82. Velocity data was integrated to compute diagnostic plate cross section profiles. Velocity data was differentiated to compute a peak pressure under the diagnostic plate at the central axis of 78 kilobars at 11.9 and 21.2 microseconds. Substantial motion (>1 m/s) of the diagnostic plate over the dead-zone is followed by detonation region motion within approximately 4.1 microseconds.

  3. Jack Rabbit Pretest 2021E PT7 Photonic Doppler Velocimetry Data Volume 7 Section 1

    SciTech Connect

    Hart, M M; Strand, O T; Bosson, S T; Bonner, R A; Hester, D M

    2008-06-25

    The Jack Rabbit Pretest (PT) 2021E PT7 experiment was fired on April 3, 2008 at the Contained Firing Facility, Site 300, Lawrence Livermore National Laboratory. This experiment is part of an effort to determine the properties of LX-17 in a regime where corner-turning behavior and dead-zone formation are not well understood. Photonic Doppler Velocimetry (PDV) measured diagnostic plate velocities confirming the presence of a persistent LX-17 dead-zone formation and the resultant impulse gradient applied under the diagnostic plate. The Jack Rabbit Pretest 2021E PT7, 160 millimeter diameter experiment returned data on all eight PDV probes. The probes measured on the central axis and at 20, 30, 35, 45, 55, 65, 75 millimeters from the central axis. The experiment was shot at an ambient room temperature of 65 degrees Fahrenheit. The PDV earliest signal extinction was 50.7 microseconds at 45 millimeters. The latest PDV signal extinction time was 65.0 microseconds at 20 millimeters. The measured velocity ranged from meters per second to thousands of meters per second. First detonation wave induced jump-off was measured at 55 millimeters and at 15.2 microseconds. The PDV data provided an unambiguous indication of dead-zone formation and an impulse gradient applied to the diagnostic plate. The central axis had a last measured velocity of 1447 meters per second. At 65 millimeters the last measured velocity was 2360 meters per second. The low-to-high velocity ratio was 0.61. Velocity data was integrated to compute diagnostic plate cross section profiles. Velocity data was differentiated to compute a peak pressure under the diagnostic plate at the central axis of 49 kilobars at 23.3 microseconds. Substantial motion (>1 m/s) of the diagnostic plate over the dead-zone is followed by detonation region motion within approximately 4.6 microseconds.

  4. Jack Rabbit Pretest 2021E PT3 Photonic Doppler Velocimetry Data Volume 3 Section 1

    SciTech Connect

    Hart, M M; Strand, O T; Bosson, S T; Bonner, R A; Hester, D M

    2008-06-25

    The Jack Rabbit Pretest (PT) 2021E PT3 was fired on March 12, 2008 at the Contained Firing Facility, Site 300, Lawrence Livermore National Laboratory. This experiment is part of an effort to determine the properties of LX-17 in a regime where corner-turning behavior and dead-zone formation are not well understood. Photonic Doppler Velocimetry (PDV) measured diagnostic plate velocities confirming the presence of a persistent LX-17 dead-zone formation and the resultant impulse gradient applied under the diagnostic plate. The Jack Rabbit Pretest 2021E PT3, 120 millimeter diameter experiment returned data on all eight PDV probes. The probes measured on the central axis and at 10, 20, 25, 30, 35, 40, 50 millimeters from the central axis. The experiment was shot at an ambient room temperature of 65 degrees Fahrenheit. The earliest PDV signal extinction was 41.7 microseconds at 30 millimeters. The latest PDV signal extinction time was 65.0 microseconds at 10 millimeters. The measured velocity ranged from meters per second to thousands of meters per second. First detonation wave induced jump-off was measured at 40 millimeters at 10.9 microseconds. The PDV data provided an unambiguous indication of dead-zone formation and an impulse gradient applied to the diagnostic plate. The central axis had a last measured velocity of 1636 meters per second. At 40 millimeters the last measured velocity was 2056 meters per second. The low-to-high velocity ratio was 0.80. Velocity data was integrated to compute diagnostic plate cross section profiles. Velocity data was differentiated to compute a peak pressure under the diagnostic plate at the central axis of 64.6 kilobars at 15.7 microseconds. Substantial motion (>1 m/s) of the diagnostic plate over the dead-zone is followed by detonation region motion within approximately 2.2 microseconds.

  5. In-Situ Monitoring of the Microstructure of TATB-based Explosive Formulations During Temperature Cycling using Ultra-small Angle X-ray Scattering

    SciTech Connect

    Willey, T M; Hoffman, D M; van Buuren, T; Lauderbach, L; Ilavsky, J; Gee, R H; Maiti, A; Overturf, G; Fried, L

    2008-02-06

    TATB (1,3,5 triamino-2,4,6-trinitrobenzene), an extremely insensitive explosive, is used both in plastic-bonded explosives (PBXs) and as an ultra-fine pressed powder (UFTATB). With both PBXs and UFTATB, an irreversible expansion occurs with temperature cycling known as ratchet growth. In TATB-based explosives using Kel-F 800 as binder (LX-17 and PBX-9502), additional voids, sizes hundreds of nanometers to a few microns account for much of the volume expansion caused by temperature cycling. These voids are in the predicted size regime for hot-spot formation during ignition and detonation, and thus an experimental measure of these voids is important feedback for hot-spot theory and for determining the relationship between void size distributions and detonation properties. Also, understanding the mechanism of ratchet growth allows future choice of explosive/binder mixtures to minimize these types of changes to explosives, further extending PBX shelf life. This paper presents the void size distributions of LX-17, UFTATB, and PBXs using commercially available Cytop M, Cytop A, and Hyflon AD60 binders during temperature cycling between -55 C and 70 C. These void size distributions are derived from ultra-small angle x-ray scattering (USAXS), a technique sensitive to structures from about 10 nm to about 2 mm. Structures with these sizes do not appreciably change in UFTATB, indicating voids or cracks larger than a few microns appear in UFTATB during temperature cycling. Compared to Kel-F 800 binders, Cytop M and Cytop A show relatively small increases in void volume from 0.9% to 1.3% and 0.6% to 1.1%, respectively, while Hyflon fails to prevent irreversible volume expansion (1.2% to 4.6%). Computational mesoscale models of ratchet growth and binder wetting and adhesion properties point to mechanisms of ratchet growth, and are discussed in combination with the experimental results.

  6. ARROW-PAK Macroencapsulation. Innovative Technology Summary Report

    SciTech Connect

    2002-04-01

    An ARROW-PAK is a high density polyethylene (HDPE) tube, about 21 feet long and 30 inches wide. Each ARROW-PAK can hold the equivalent of 21 55-gallon drums of mixed waste debris. Each tube is fused to HDPE endcaps using localized heating and high pressure contact. The sleeves and encaps form a tube for macroencapsulating mixed waste debris. The ARROW-PAK may achieve a mixed waste debris volume one-fourth that of the conventional macroencapsulation approach. The mixed waste debris is loaded into 55-gallon drums. Once filled a 'supercompactor' crushes the drums into 12-inch thick pucks. Three pucks can be loaded into a standard 85-gallon metal drum known as an 'overpack'. Seven overpacks fit into each ARROW-PAK.

  7. Discrepant Results in a 2-D Marble Collision

    NASA Astrophysics Data System (ADS)

    Kalajian, Peter

    2013-03-01

    Video analysis of 2-D collisions is an excellent way to investigate conservation of linear momentum. The often-desired experimental design goal is to minimize the momentum loss in order to demonstrate the conservation law. An air table with colliding pucks is an ideal medium for this experiment, but such equipment is beyond the budget of many schools. Substituting marbles on a table for air pucks introduces angular momentum and sliding friction so that simple video analysis will demonstrate that linear momentum is not conserved.1,2 Nevertheless, these labs offer students insights into the real-world application of physics. During a recent classroom trial, an unexpected result forced my students to think creatively and critically about what happened in the experiment.

  8. Using Gliders to Resolve Dynamics of Dust and Phytoplankton in the Mediterranean

    DTIC Science & Technology

    2008-01-01

    measured with the physical/optical sensor packages mounted on Webb gliders. We propose to use Webb Gliders to provide a regional subsurface physical and...2) coordinate the activities of a fleet Gliders that are outfitted with a variety of sensors to quantify the physical hydrography of the...integrated the AUVB scattering sensor . These scattering sensors will be complemented with WetLabs pucks, which will provide the measurements of spectral

  9. Using Gliders to Resolve Dynamics of Dust and Phytoplankton in the Mediterranean

    DTIC Science & Technology

    2010-01-01

    spatial subsurface measurements, which can be measured with the physical/optical sensor packages mounted on Webb gliders. We propose to use Webb...are outfitted with a variety of sensors to quantify the physical hydrography of the coastal and offshore waters in the Mediterranean, the apparent and...scattering sensor . These scattering sensors will be complemented with WetLabs pucks, which will provide the measurements of spectral backscatter. The

  10. Granulator Selection

    SciTech Connect

    Gould, T H; Armantrout, G

    1999-08-02

    Following our detailed review of the granulation reports and additional conversations with process and development personnel, we have reached a consensus position regarding granulator selection. At this time, we recommend going forward with implementation of the tumbling granulator approach (GEMCO) based on our assessment of the tested granulation techniques using the established criteria. The basis for this selection is summarized in the following sections, followed by our recommendations for proceeding with implementation of the tumbling granulation approach. All five granulation technologies produced granulated products that can be made into acceptable sintered pucks. A possible exception is the product from the fluidized bed granulator. This material has been more difficult to press into uniform pucks without subsequent cracking of the puck during the sintering cycle for the pucks in this series of tests. This problem may be an artifact of the conditions of the particular granulation demonstration run involved, but earlier results have also been mixed. All granulators made acceptable granulated feed from the standpoint of transfer and press feeding, though the roller compactor and fluidized bed products were dustier than the rest. There was also differentiation among the granulators in the operational areas of (1) potential for process upset, (2) plant implementation and operational complexity, and (3) maintenance concerns. These considerations will be discussed further in the next section. Note that concerns also exist regarding the extension of the granulation processes to powders containing actinides. Only the method that involves tumbling and moisture addition has been tested with uranium, and in that instance, significant differences were found in the granulation behavior of the powders.

  11. Formation and corrosion of a 410 SS/ceramic composite

    NASA Astrophysics Data System (ADS)

    Chen, X.; Ebert, W. L.; Indacochea, J. E.

    2016-11-01

    This study addressed the possible use of alloy/ceramic composite waste forms to immobilize metallic and oxide waste streams generated during the electrochemical reprocessing of spent reactor fuel using a single waste form. A representative composite material was made to evaluate the microstructure and corrosion behavior at alloy/ceramic interfaces by reacting 410 stainless steel with Zr, Mo, and a mixture of lanthanide oxides. Essentially all of the available Zr reacted with lanthanide oxides to generate lanthanide zirconates, which combined with the unreacted lanthanide oxides to form a porous ceramic network that filled with alloy to produce a composite puck. Alloy present in excess of the pore volume of the ceramic generated a metal bead on top of the puck. The alloys in the composite and forming the bead were both mixtures of martensite grains and ferrite grains bearing carbide precipitates; FeCrMo intermetallic phases also precipitated at ferrite grain boundaries within the composite puck. Micrometer-thick regions of ferrite surrounding the carbides were sensitized and corroded preferentially in electrochemical tests. The lanthanide oxides dissolved chemically, but the lanthanide zirconates did not dissolve and are suitable host phases. The presence of oxide phases did not affect corrosion of the neighboring alloy phases.

  12. Chiropractic management of a patient with postoperative lateral retinacular release using a multimodal approach: a case report

    PubMed Central

    Solecki, Thomas J.; Hostnik, Kurt D.

    2012-01-01

    Objective The purpose of this case report is to describe a chiropractic rehabilitation program for a patient with postsurgical lateral retinaculum release. Clinical Features A 26-year-old male ice hockey goalie presented 1 month after having lateral retinaculum release surgery for his left knee with residual mild discomfort and edema in his left knee. Intervention and Outcome The patient was treated using a multimodal approach of both passive and active chiropractic care focusing on the restoration of full range of motion, increased proprioception, balance, strength, and endurance to return the patient to competitive ice hockey. Conclusion This case study demonstrated that, after 14 weeks of care, the patient was able to return to ice hockey training with no residual symptoms. PMID:22942841

  13. Physics of ball sports

    NASA Astrophysics Data System (ADS)

    Cohen, C.; Clanet, C.

    2016-06-01

    Ball sports have been part of human history for thousands of years [1]. Nowadays, 13 of them are part of the Olympic games (badminton, basketball, beach volley, football/soccer, golf, handball, hockey, rugby, table tennis, tennis, volleyball, water polo, ice hockey). All these games differ by launcher (hand, club, racket, bat), ball (size, shape and mass), pitch size and number of players. These differences induce different ball velocities. Apart from the velocities and the way to maximize them, we discuss in this article the ball trajectories and their impact on the size of sports fields.

  14. Designing the Next Generation of Human Spacecraft

    NASA Technical Reports Server (NTRS)

    Simmons, Emily

    2016-01-01

    Lunar Space Station Common Module: A new concept for a module for a lunar space station attempts to reduce the module's mass by abandoning the traditional rack structure currently used on the ISS for the mounting of internal hardware and replacing it with a core structure. By using this design, the pressure shell will not have to carry the loads resulting from the internal mass. I worked with another intern to create the initial design for the module, with him focusing on the core and myself focusing on the pressure shell. To start, I was given the shell overall dimensions and material and tasked with sizing the wall thickness and placing stiffeners such that the shell could withstand the required loads. At the same time, I had to keep the mass to a minimum to keep the overall module within the allowable launch mass. Once I had done initial sizing based on pressure loads, I combined the pressure shell with the inner core to perform optimization of the design. Currently, the design involves circumferential stiffeners along the entire length of the pressure shell with longitudinal stiffeners on either end. In addition, extra wall thickness was added around each of the hatches. At this stage, the design shows a comparable mass to a more traditional design, but we are hopeful that, through optimization, we will be able to reduce the mass even further. There is currently a patent pending for the module design, for which I am listed as a co-inventor. ALON Material Testing: I was given samples of aluminum oxynitride (ALON) that had been impacted by a previous intern on which to perform residual strength tests as part of a plan to approve them for space use. Before testing, I measured the pucks and their damages using a ruler and optical micrometer in order to verify that the puck dimensions were within the tolerances set by the test guidelines and that the damages had not grown when the pucks were thinned. The test was a ring-ring test, which used two concentric rings to

  15. Moisture Outgassing Rates from TATB-Formulations: Experiments and Kinetic Model Development

    SciTech Connect

    Glascoe, E A; Dinh, L N; Small IV, W

    2009-07-29

    Moisture outgassing rates from materials are of interest and importance to a variety of different fields. Because water can attack and accelerate decomposition, aging, or rusting of various parts, the assembly of an apparatus with 'wet' materials can shorten the lifetime of the apparatus. Outgassing of moisture from materials can be quite slow and a material that is seemingly dry at the time of assembly may slowly release water over years. This slow release of water will compromise the other constituents of the apparatus (e.g. electrical components, metals, organic materials) and shorten the lifetime of the apparatus. For apparatuses that are expensive or laborious to construct, it is especially important to understand and be able to predict the mechanisms and rates of water release from various materials. Such an understanding can support the development of accurate estimates of the apparatus's serviceable age and may allow for mitigation strategies in order to protect other parts from water. Energetic materials such as TATB based PBX-9502 (95% TATB, 5% Kel-F 800) and LX-17 (92.5% TATB and 7.5% Kel-F) pose a particularly challenging problem because they are heterogeneous materials with potentially many different sources and mechanisms of water release. Water molecules could be adsorbed into the polymeric binder matrix, trapped in occlusions within the polymer and the TATB crystals/particles, or trapped within defect sites in the TATB crystal. Finally, many studies indicate that water is a decomposition product under rapid heating conditions, at high temperatures and/or high pressure. Previous studies have measured the water release rate(s) from LX-17 or PBX-9502 prill/powder in order to establish oven drying times prior to use. These studies limited their time frame to a few days or a week of drying. Other studies have looked at the rate of water release of large pressed parts contained in sealed containers. Finally, some studies have looked at the rate of water

  16. Transition into College Sports: The Freshman Student-Athlete.

    ERIC Educational Resources Information Center

    Purdy, Dean; And Others

    Changes in attitude, motivation, and values take place in the academic, athletic, and social areas of student-athletes' lives during their freshman year of college. Twenty incoming college freshman athletes involved in "revenue" sports (football, basketball, and ice hockey) participated in this study and were interviewed in the fall and again in…

  17. Athletes' Evaluations of Their Head Coach's Coaching Competency

    ERIC Educational Resources Information Center

    Myers, Nicholas D.; Feltz, Deborah L.; Maier, Kimberly S.; Wolfe, Edward W.; Reckase, Mark D.

    2006-01-01

    This study provided initial validity evidence for multidimensional measures of coaching competency derived from the Coaching Competency Scale (CCS). Data were collected from intercollegiate men's (n = 8) and women's (n = 13) soccer and women's ice hockey teams (n = 11). The total number of athletes was 585. Within teams, a multidimensional…

  18. A Laboratory/Field Study of Television Violence and Aggression in Children's Sports.

    ERIC Educational Resources Information Center

    McCabe, Ann E.; Moriarty, Richard J.

    A study on the effect of viewing violence on television on childrens' behavior was conducted within the context of sport activity. Three sports--baseball, hockey, and lacrosse--were chosen. Teams of children from three different age groups were the subjects. Within each of the age levels in each sport, teams were selected and assigned to…

  19. 18 CFR 1317.415 - Access to course offerings.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... physical education classes or activities during participation in wrestling, boxing, rugby, ice hockey... NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Discrimination on the Basis of Sex in Education Programs or Activities Prohibited § 1317.415 Access to...

  20. 18 CFR 1317.415 - Access to course offerings.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... physical education classes or activities during participation in wrestling, boxing, rugby, ice hockey... NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Discrimination on the Basis of Sex in Education Programs or Activities Prohibited § 1317.415 Access to...

  1. 14 CFR 1253.415 - Access to course offerings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... physical education classes or activities during participation in wrestling, boxing, rugby, ice hockey... THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Discrimination on the Basis of Sex in Education Programs or Activities Prohibited § 1253.415 Access to...

  2. 18 CFR 1317.415 - Access to course offerings.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... physical education classes or activities during participation in wrestling, boxing, rugby, ice hockey... NONDISCRIMINATION ON THE BASIS OF SEX IN EDUCATION PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Discrimination on the Basis of Sex in Education Programs or Activities Prohibited § 1317.415 Access to...

  3. Some Ways of Helping Underachievers.

    ERIC Educational Resources Information Center

    Willings, David; Greenwood, Bill

    1990-01-01

    A program of intervention called therapeutic tutoring to help underachievers is described. Intervention centers around students' loci of control, through a process of identifying areas in which students feel empowered and relating academic experiences to these areas. Academic exercises based on Monopoly, cricket, rugby, soap operas, field hockey,…

  4. Are Children's Competitive Team Sports Socializing Agents for Corporate America?

    ERIC Educational Resources Information Center

    Berlage, Gai Ingham

    In a study of the similarities between childrens' competitive team sports and the typical corporate or business environment, two research questions were posed: (1) Does the structural organization of childrens' soccer and ice hockey organizations resemble that of American corporations?; and (2) Are the values of childrens' competitive sports…

  5. Sports Involvement and Academic Achievement: A Study of Malaysian University Athletes

    ERIC Educational Resources Information Center

    Chuan, Chun Cheng; Yusof, Aminuddin; Shah, Parilah Mohd

    2013-01-01

    Factors that influence the academic achievement of Malaysian university athletes were investigated using 156 field hockey players from several universities. The relationship between team subculture, parental influence, the learning environment, support systems, financial aid, training factors, academic assistance, socialization, and stress level…

  6. Beyond the game: the legacy of Bill Masterton.

    PubMed

    Bonfield, Christopher M; Kondziolka, Douglas

    2016-07-01

    Bill Masterton is the only man to die of injuries sustained in a National Hockey League (NHL) game. He remains the last fatality in any professional team sport involving a direct in-game injury in North America. While Masterton was originally thought to have suffered a fatal brain injury while being checked on the ice, later analysis of the case revealed evidence of second-impact syndrome and the effects of prior concussions. Masterton's death sparked both an immediate debate in the NHL on whether helmets should be compulsory and the NHL's first vote on mandatory helmet use. Although the subject of mandated helmet use met with resistance in the 10 years after Masterton's death, especially from hockey owners and coaches, the NHL finally legislated helmet use by all players entering the league beginning in the 1979-1980 season. Several awards, including one recognizing the NHL player who best exemplifies the qualities of perseverance, sportsmanship, and dedication to hockey, have been created in memory of Masterton. However, his legacy extends far beyond the awards that bear his name. His death was the seminal event bringing head safety to the forefront of a game that was both unready and unwilling to accept change. An increase in mainstream media attention in recent years has led to unprecedented public awareness of brain injury and concussion in hockey and other sports. Advances in the diagnosis and treatment of head injury in sports have occurred recently, the impetus for which started over 45 years ago, when Bill Masterton died.

  7. Lunar Cycles and Human Aggression: A Replication.

    ERIC Educational Resources Information Center

    Russell, Gordon W.; de Graaf, Jane P.

    1985-01-01

    Tested lunar-aggression hypothesis using the aggressive penalties awarded in ice hockey over a season of competition. Interpersonal aggression was found to be unrelated to either the synodic or anomalistic cycles. Discussion centers on the persistence of lunar beliefs and their links to the literature on selective exposure and interpersonal…

  8. The Analysis of the Thinking Styles and Creativity of the Sports Students Studying in the Different Fields of University

    ERIC Educational Resources Information Center

    Eraslan, Meric

    2014-01-01

    This study analyzes the creativity and thinking levels of athletes studying at the different college departments; 61 female and 75 male athletes, a total of 136 ice-hockey players have participated in the research. As data collection tools, Thinking Styles Inventory and The Creativity Scale have been used in the study. SPSS 15.0 for Windows…

  9. The Development of Ojibway Language Materials.

    ERIC Educational Resources Information Center

    Pheasant-Williams, Shirley

    2003-01-01

    Revitalization of the Nishinaabeg language started in 1998 with the development of language materials. A committee on Nishinaabemwin orthography advised on the development of the text and writing system. Teaching methods follow the four parts of Medicine Wheel teachings: spiritual, emotional, physical, and mental. An interactive hockey game and a…

  10. Teaching Methods Effectiveness and the Acquisition of Psycho-Motor Skills.

    ERIC Educational Resources Information Center

    Ikulayo, Philomena Bolaji

    An experimental study was conducted to discover the relative effectiveness of five different instructional strategies on the acquisition of four psycho-motor skills associated with four physical sports (continuous volleying in volleyball, zig-zag dribbling in field hockey, headstand in gymnastics, and sail long jump in athletics). The subjects…

  11. Biography Today: Sports Series. Profiles of People of Interest to Young Readers. Volume 3, 1999.

    ERIC Educational Resources Information Center

    Harris, Laurie Lanzen, Ed.; Abbey, Cherie D., Ed.

    This third volume is part of a series of biographies that profile individuals of interest to young people over the age of 9 years. The entries in this volume include Joe Dumars, basketball; Jim Harbaugh, football; Dominik Hasek, hockey; Michelle Kwan, figure skating; Rebecca Lobo, basketball; Greg Maddux, baseball; Fatuma Roba, marathon running;…

  12. An Analysis of Nondestructive Evaluation Techniques for Polymer Matrix Composite Sandwich Materials

    NASA Technical Reports Server (NTRS)

    Cosgriff, Laura M.; Roberts, Gary D.; Binienda, Wieslaw K.; Zheng, Diahua; Averbeck, Timothy; Roth, Donald J.; Jeanneau, Philippe

    2006-01-01

    Structural sandwich materials composed of triaxially braided polymer matrix composite material face sheets sandwiching a foam core are being utilized for applications including aerospace components and recreational equipment. Since full scale components are being made from these sandwich materials, it is necessary to develop proper inspection practices for their manufacture and in-field use. Specifically, nondestructive evaluation (NDE) techniques need to be investigated for analysis of components made from these materials. Hockey blades made from sandwich materials and a flat sandwich sample were examined with multiple NDE techniques including thermographic, radiographic, and shearographic methods to investigate damage induced in the blades and flat panel components. Hockey blades used during actual play and a flat polymer matrix composite sandwich sample with damage inserted into the foam core were investigated with each technique. NDE images from the samples were presented and discussed. Structural elements within each blade were observed with radiographic imaging. Damaged regions and some structural elements of the hockey blades were identified with thermographic imaging. Structural elements, damaged regions, and other material variations were detected in the hockey blades with shearography. Each technique s advantages and disadvantages were considered in making recommendations for inspection of components made from these types of materials.

  13. Internet-Accessible Scholarly Resources for the Humanities and Social Sciences.

    ERIC Educational Resources Information Center

    ACLS Newsletter, 1997

    1997-01-01

    This newsletter focuses on the presentations of a program session on Internet-accessible scholarly resources, held at the 1996 ACLS Annual Meeting. Articles in the newsletter include: "Building the Scene: Words, Images, Data, and Beyond" (David Green); "Electronic Texts: The Promise and the Reality" (Susan Hockey); "Images…

  14. A Descriptive-Analytic Study of the Practice Field Behavior of a Winning Female Coach.

    ERIC Educational Resources Information Center

    Dodds, Patt; Rife, Frank

    A winning collegiate field hockey coach was observed across seventeen practice sessions through one complete competitive season. A category system for the event recording of verbal and nonverbal behaviors delivered to the team and to the sixteen individual players produced descriptive-analytic information about relative behavior frequencies for…

  15. Fit by Five.

    ERIC Educational Resources Information Center

    Wells, Maureen

    1978-01-01

    Describes a preschool program in which all skills, including academic and social skills, are taught through movement. Children are introduced to over 300 physical activities and sports in a year's time including: balance beam, parallel bars, trampoline, swimming, hockey, basketball, golf, archery, track, and volleyball. (JMB)

  16. Optimizing Daytime Short Sleep Episodes to Maximize Performance in a Stressful Environment

    DTIC Science & Technology

    2006-09-01

    Performance deficits following short-term partial sleep deprivation and subsequent recovery oversleeping . Can J Psychol, 35(4), 309-322. Hockey...sleep deprivation and subsequent recovery oversleeping . Can J Psychol, 35(4), 309-322. Johnson, L. C., and Naitoh, P. (1974). The operational

  17. Plyometrics: A Legitimate Form of Power Training?

    ERIC Educational Resources Information Center

    Duda, Marty

    1988-01-01

    Plyometric exercises or drills combine speed and strength to produce an explosive-reactive movement or increased power. Some world-class athletes have used plyometric-training in sports such as high-jumping, hurdles, football, baseball, and hockey. The method is still considered experimental. Sample exercises are described. (JL)

  18. Speed-A-Way, Physical Education: 5551.14.

    ERIC Educational Resources Information Center

    King, Katheryn

    This course outline is a guide (grades 7-12) for teaching speed-a-way, a game combining soccer, basketball, speedball, and field hockey skills. The course format includes discussions, demonstrations, skills practice, films, and tests that focus on mastery of skills, understanding of rules and officiating, testing skill performance and rules…

  19. Enhancing Care and Advocacy for Sexual Assault Survivors on Canadian Campuses

    ERIC Educational Resources Information Center

    Quinlan, Elizabeth; Clarke, Allyson; Miller, Natasha

    2016-01-01

    Recent media coverage of the rape chant at Saint Mary's University, the misogynist Facebook posts at Dalhousie's dental school, and the suspension of the University of Ottawa's hockey team have brought the topic of campus sexual assault under intense public scrutiny and the media accounts point to a widespread systemic rape culture on Canadian…

  20. The Role of Personal Experience in the Neural Processing of Action-Related Language

    ERIC Educational Resources Information Center

    Lyons, Ian M.; Mattarella-Micke, Andrew; Cieslak, Matthew; Nusbaum, Howard C.; Small, Steven L.; Beilock, Sian L.

    2010-01-01

    We investigated how auditory language processing is modified by a listener's previous experience with the specific activities mentioned in the speech. In particular, we asked whether neural responses related to language processing depend on one's experience with the action-based content of this language. Ice-hockey players and novices passively…

  1. The Lived Experience of a Doctoral Student: The Process of Learning and Becoming

    ERIC Educational Resources Information Center

    Callary, Betina; Werthner, Penny; Trudel, Pierre

    2012-01-01

    The PhD experience is often a transition from student to future faculty member, which involves considerable learning and development (Glaze, 2002; Hockey, 2004). Using a lifelong learning perspective (Jarvis, 2009), the purpose of this article is to explore, through a reflective self-study, my process of learning throughout the PhD degree. In this…

  2. Social Cognitive Correlates of Young Adult Sport Competitors' Sunscreen Use

    ERIC Educational Resources Information Center

    Berndt, Nadine C.; O'Riordan, David L.; Winkler, Elisabeth; McDermott, Liane; Spathonis, Kym; Owen, Neville

    2011-01-01

    Young adults participating in outdoor sports represent a high-risk group for excessive sun exposure. The purpose of this study was to identify modifiable social cognitive correlates of sunscreen use among young adult competitors. Participants aged 18 to 30 years who competed in soccer (n = 65), surf-lifesaving (n = 63), hockey (n = 61), and tennis…

  3. A Case Study of Wikis and Student-Designed Games in Physical Education

    ERIC Educational Resources Information Center

    Hastie, Peter A.; Casey, Ashley; Tarter, Anne-Marie

    2010-01-01

    This paper reports on the incorporation of wiki technology within physical education. Boys from two classes at a school in the United Kingdom were divided into small teams and given the task of creating a new game in a same genre as football, hockey, netball or rugby. Each team had a wiki on which were recorded all the plans and developments of…

  4. Athletes, Doctors, and Lawyers with First Names Beginning with "D" Die Sooner

    ERIC Educational Resources Information Center

    Abel, Ernest L.; Kruger, Michael L.

    2010-01-01

    For many people, names have symbolic power that extends to their timing of death. This study examined the relationship between the symbolic significance of the first letters in the names of professional athletes (baseball, football, hockey, and basketball) and their longevity. A similar analysis was performed for doctors (radiologists,…

  5. Staying at the Top: Playing Position and Performance Affect Career Length in Professional Sport

    ERIC Educational Resources Information Center

    Baker, Joseph; Koz, Dan; Kungl, Ann-Marie; Fraser-Thomas, Jessica; Schorer, Jorg

    2013-01-01

    In an effort to understand the process of skill acquisition and decline, researchers have largely neglected a critical aspect of this development--maximizing time at the highest levels of achievement. This study examined length of career for professional athletes in basketball, football, ice hockey, and baseball and considers whether career length…

  6. Questionable Supervision by Physical Educators

    ERIC Educational Resources Information Center

    Sawyer, Thomas H.; Gimbert, Tonya L.

    2013-01-01

    According to Court records, student Pedro Godoy (Godoy) filed a suit against the school district (Central Islip Union Free School District) and teacher Otis R. Scerbo (Scerbo), seeking to recover damages for personal injuries allegedly sustained by Godoy while participating in a game of floor hockey during physical education class. Scerbo (the…

  7. The Pasternak Case and American Gender Equity Policy: Implications for Canadian High School Athletics

    ERIC Educational Resources Information Center

    Beaubier, Dean M.; Gadbois, Shannon A.; Stick, Sheldon L.

    2011-01-01

    In 2004 twin sisters Amy and Jesse Pasternak competed for the prospect of playing high school hockey, vying for the boys' team rather than the girls'. The sisters' opportunities were negated by the Manitoba High School Athletic Association (MHSAA). This paper examines the 2006 decision by the Manitoba Human Rights Commission and a 2008 judgment by…

  8. 1998 Arthur Ashe Jr. Sports Scholars Awards.

    ERIC Educational Resources Information Center

    Chenoweth, Karin; Evelyn, Jamilah

    1998-01-01

    Announces the Sports Scholars Awards for 1998. One male and one female college athlete are profiled, and others are named for baseball, softball, basketball, fencing, riflery, bowling, football, wrestling, soccer, lacrosse, field hockey, swimming/diving, gymnastics, crew, tennis, golf, volleyball, track/field, cross country, downhill skiing, and…

  9. Girls Physical Education Handbook.

    ERIC Educational Resources Information Center

    Fairfax County Schools, VA.

    This handbook was designed to provide the student with basic information for various individual, dual, and team sports. The individual and dual sports which are discussed include archery, badminton, creative dance, fencing, golf, gymnastics, and games such as deck tennis, table tennis, horseshoes, and shuffledboard. Basketball, field hockey,…

  10. Lunar Influences on Human Aggression.

    ERIC Educational Resources Information Center

    Russell, Gordon W.; Dua, Manjula

    1983-01-01

    Used league records of all Canadian hockey games (N=426) played during a season to test a lunar-aggression hypothesis. Despite the use of multiple measures of lunar phase and interpersonal aggression, support for lunar influence was not forthcoming. Supplemental data revealed that beliefs in lunar influence are fairly common. (JAC)

  11. Sports, Youth and Character: A Critical Survey. CIRCLE Working Paper 44

    ERIC Educational Resources Information Center

    Fullinwider, Robert K.

    2006-01-01

    Roughly forty million boys and girls between the ages of 5 and 18 take part in organized athletic activities, most of which are not school-based. Boys and girls play in sports as varied as swimming, baseball, soccer, wrestling, and field hockey. The great majority participate in "recreational" leagues in which teams enroll all-comers, compete…

  12. Comparative Evaluation of Two Serial Gene Expression Experiments | Division of Cancer Prevention

    Cancer.gov

    Stuart G. Baker, 2014 Introduction This program fits biologically relevant response curves in comparative analysis of the two gene expression experiments involving same genes but under different scenarios and at least 12 responses. The program outputs gene pairs with biologically relevant response curve shapes including flat, linear, sigmoid, hockey stick, impulse and step curves. |

  13. The National Association for Girls and Women in Sport: 110 Years of Promoting Social Justice and Change

    ERIC Educational Resources Information Center

    Ladda, Shawn

    2009-01-01

    From writing the first Guidebooks for hockey, soccer, swimming, track and field, and basketball, to lobbying Congress to strive for equity and equal opportunities for girls, the National Association for Girls and Women in Sport (NAGWS) has been and continues to be the beacon in education to advance fairness and equity in sports. As NAGWS enters…

  14. Leadership Development of Team Captains in Collegiate Varsity Athletics

    ERIC Educational Resources Information Center

    Grandzol, Christian; Perlis, Susan; Draina, Lois

    2010-01-01

    This study examined the leadership development of team captains and student-athletes engaged in NCAA Division III intercollegiate athletics at 6 private institutions of higher education. Student-athletes in the sports of men's and women's soccer, women's field hockey, men's and women's cross country, and women's tennis completed the 2nd edition of…

  15. Five Year Overview of Sport Injuries: The NAIRS Model.

    ERIC Educational Resources Information Center

    Buckley, William E.

    1982-01-01

    Data from a survey of institutional members of the National Athletic Injury/Illness Reporting System (NAIRS) are presented and discussed. Included are tables showing injuries reported in high schools and colleges and universities for male and female athletes in baseball, basketball, football, gymnastics, soccer, wrestling, field hockey, track and…

  16. Mathematics and Sports. Mathematical World. Volume 3.

    ERIC Educational Resources Information Center

    Sadovskii, L. E.; Sadovskii, A. L.

    This volume contains some examples of mathematical applications in sports. Sports discussed include tennis, figure skating, gymnastics, track and field, soccer, skiing, hockey, and swimming. Problems and situations are posed and answers with thorough explanations are provided. Chapters include: (1) Mathematics and Sports; (2) What Is Applied…

  17. Alpine Skiing in the Classroom

    ERIC Educational Resources Information Center

    Mendez-Gimenez, Antonio; Fernandez-Rio, Javier

    2012-01-01

    Many students settle indoors in the winter. However, this does not mean that winter should be a period of time with no physical activity. Several snow activities could be practiced during those months, such as ice-skating, ice-hockey, snowshoeing, cross-country skiing, alpine skiing, or snowboarding. In order to counteract the tendency for…

  18. "Emerging" Sports for Women.

    ERIC Educational Resources Information Center

    Blum, Debra E.

    1994-01-01

    The National Collegiate Athletic Association has recently introduced nine new sports to intercollegiate athletics: team handball, archery, badminton, bowling, crew, ice hockey, squash, synchronized swimming, and water polo. The initiative is intended to encourage colleges to create more athletic opportunities for women. It sets scholarship limits…

  19. A Survey to Determine to What Extent Ohlone College Is Meeting the Needs of Student Athletes.

    ERIC Educational Resources Information Center

    Baker, John

    A questionnaire was administered to all 1978 fall quarter student athletes at Ohlone College (California) to assess their goals and needs, and to find out to what degree student experience matched expectation. There was an 86% (N=85) response rate from the varsity men and women teams (volleyball, field hockey, soccer, water polo, and football).…

  20. 1997 Arthur Ashe Jr. Sport Scholars Awards.

    ERIC Educational Resources Information Center

    Roach, Ronald

    1997-01-01

    Winners of the "Black Issues in Higher Education" Arthur Ashe Jr. 1997 athletes of the year, one male and one female, are profiled and Sport Scholars are listed for baseball, softball, basketball, fencing, archery, football, handball, soccer, field hockey, crew, swimming, gymnastics, tennis, squash, golf, volleyball, lacrosse, wrestling, water…

  1. Violence in Sports.

    ERIC Educational Resources Information Center

    Cooper, Donald L.

    Increasing violence in sports is deplored, and a warning is issued on an apparent trend toward antisocial behavior. Contact sports such as hockey and football are cited as typically engendering aggression among athletes, but spectator sports (boxing, car racing, basketball, and baseball) are also singled out as eliciting increasing violence on the…

  2. A Battle over a Name in the Land of the Sioux: A Controversy over a Mascot at the U. of North Dakota Turned Surreal When a Benefactor Threatened To Withdraw $100 Million.

    ERIC Educational Resources Information Center

    Brownstein, Andrew

    2001-01-01

    Discusses the controversy that erupted when the University of North Dakota planned to drop its "Fighting Sioux" nickname and mascot, a benefactor announced his intention of withdrawing a $100 million gift and halting construction of an ice hockey arena. Describes the implications of the university's decision to retain the name for its…

  3. A Pirate's Life: A Model and a Metaphor for Learning.

    ERIC Educational Resources Information Center

    Solomon, David L.

    2002-01-01

    Discusses various ways in which context may be interpreted to enhance learning and performance; illustrates domains of learning using a hockey team as an example; and suggests implications for learning, performance, and instructional design. Highlights include an ecological systems model; and examples of individual development, team learning, and…

  4. Top climatologist faces 'witch hunt'

    NASA Astrophysics Data System (ADS)

    Gwynne, Peter

    2010-06-01

    Researchers have come out in protest against an investigation looking into grants obtained by the climate scientist Michael Mann, director of Pennsylvania State University's Earth System Science Center, and creator of the widely accepted "hockey-stick graph" showing the recent surge in temperatures caused by climate change.

  5. Regressing Team Performance on Collective Efficacy: Considerations of Temporal Proximity and Concordance

    ERIC Educational Resources Information Center

    Myers, Nicholas D.; Paiement, Craig A.; Feltz, Deborah L.

    2007-01-01

    The purpose of this study was to determine to what degree collective efficacy judgments based on summative team performance capabilities exhibited different levels of prediction for three additive intervals of team performance in women's ice hockey. Collective efficacy beliefs of 12 teams were assessed prior to Friday's game and Saturday's game…

  6. Myth 11: A Comprehensive Continuum of Gifted Education and Talent Development Services--Discovering, Developing, and Enhancing Young People's Gifts and Talents

    ERIC Educational Resources Information Center

    Gentry, Marcia

    2009-01-01

    To determine whether having a program is sufficient one must first define what is meant by "program." If by program one refers to the pullout program in the elementary school, or the afterschool enrichment program in the middle school, or the Advanced Placement program in the high school, or the hockey program, then certainly having a "program" is…

  7. Pupils' Perceptions of and Experiences in Team Invasion Games: A Case Study of a Scottish Secondary School and Its Three Feeder Primary Schools

    ERIC Educational Resources Information Center

    Gray, Shirley; Sproule, John; Wang, C. K. John

    2008-01-01

    It has been claimed that young children in schools in Scotland cannot relate to the activities that are taught in the more "traditional" PE curriculum, activities that predominately include team invasion games (TIG) such as basketball, soccer and hockey (Scottish Executive, 2004). However, one of the issues with this claim is that it…

  8. Practical Applications of the Compound Pendulum.

    ERIC Educational Resources Information Center

    Hinrichsen, Peter F.

    1981-01-01

    Examples of the application of compound pendulum theory to the practical measurement of the moments of inertia of human beings, farm tractors, and sailing boats are presented. Suggests developing laboratory experiments to measure moments of inertia of hockey sticks, golf clubs, and frisbees, among others. (Author/SK)

  9. Sports for Life

    ERIC Educational Resources Information Center

    Schachter, Ron

    2010-01-01

    When Saul Lerner became director of physical education, athletics, and health for the Bellmore-Merrick (New York) School District 14 years ago, football, soccer, basketball, and floor hockey were staples of most physical education classes on Long Island and around the rest of the country. The mindset of physical educators was to emphasize sports…

  10. Construct-a-Glove. Science by Design Series.

    ERIC Educational Resources Information Center

    Pulis, Lee

    This book is one of four books in the Science-by-Design Series created by TERC and funded by the National Science Foundation (NSF). It offers high school students a challenging, hands-on opportunity to compare the function and design of many types of handwear from a hockey mitt to a surgical glove, and design and test a glove to their own…

  11. The Impact of Athletic Facilities on the Recruitment of Potential Student-Athletes

    ERIC Educational Resources Information Center

    Schneider, Ray; Messenger, Steve

    2012-01-01

    Purpose: This study examined the impact that athletic facilities and other college choice factors have on the recruitment of student-athletes to play Division I college hockey compared to the influence of other college choice factors. Although athletic facilities and their seeming importance in the recruitment of top level student-athletes are…

  12. Skating crossovers on a motorized flywheel: a preliminary experimental design to test effect on speed and on crossovers.

    PubMed

    Smith, Aynsley M; Krause, David A; Stuart, Michael J; Montelpare, William J; Sorenson, Matthew C; Link, Andrew A; Gaz, Daniel V; Twardowski, Casey P; Larson, Dirk R; Stuart, Michael B

    2013-12-01

    Ice hockey requires frequent skater crossovers to execute turns. Our investigation aimed to determine the effectiveness of training crossovers on a motorized, polyethylene high-resistance flywheel. We hypothesized that high school hockey players training on the flywheel would perform as well as their peers training on ice. Participants were 23 male high-school hockey players (age 15-19 years). The study used an experimental prospective design to compare players who trained for 9 sessions on the 22-foot flywheel with players who trained for 9 sessions on a similarly sized on-ice circle. Both groups were compared with control subjects who were randomly selected from the same participant pool as those training on ice. All players were tested before and after their 3-week training regimens, and control subjects were asked to not practice crossovers between testing. Group 1 trained in a hockey training facility housing the flywheel, and group 2 trained in the ice hockey arena where testing occurred. Primary outcome measures tested in both directions were: (a) speed (time in seconds) required to skate crossovers for 3 laps of a marked face-off circle, (b) cadence of skating crossovers on the similarly sized circles, and (c) a repeat interval speed test, which measures anaerobic power. No significant changes were found between groups in on-ice testing before and after training. Among the group 1 players, 7 of 8 believed they benefited from flywheel training. Group 2 players, who trained on ice, did not improve performance significantly over group 1 players. Despite the fact that no significant on-ice changes in performance were observed in objective measures, players who trained on the flywheel subjectively reported that the flywheel is an effective cost-effective alternative to training on ice. This is a relevant finding when placed in context with limited availability of on-ice training.

  13. Effects of active vs. passive recovery on work performed during serial supramaximal exercise tests.

    PubMed

    Spierer, D K; Goldsmith, R; Baran, D A; Hryniewicz, K; Katz, S D

    2004-02-01

    The current investigation was undertaken to determine the effects of active versus passive recovery on work performance during repeated bouts of supramaximal exercise. Six healthy sedentary subjects and 9 moderately trained healthy hockey players performed serial 30-second Wingate anaerobic power tests (WAnT) on a bicycle ergometer interposed with 4 minutes of active recovery at a work rate corresponding to 28 % of VO(2)max or passive recovery at rest. Peak power, mean power, total work achieved, and fatigue index were calculated for the serial WAnT. Capillary blood lactate was determined at 5-minute intervals after the last WAnT during 30 minutes of active or passive recovery. Mean power was significantly greater during active recovery in sedentary subjects when compared with passive recovery (388 +/- 42 vs. 303 +/- 37 W, p < 0.05), but did not differ according to recovery mode in moderately trained hockey players (589 +/- 22 W active vs. 563 +/- 26 W passive, p = 0.14). Total work achieved significantly increased during active when compared with passive recovery in sedentary subjects (34 890 +/- 3768 vs. 27 260 +/- 3364 J, p < 0.02) and moderately trained hockey players (86 763 +/- 9151 vs. 75 357 +/- 8281 J, p < 0.05). Capillary blood lactate levels did not differ during active when compared with passive recovery in sedentary subjects but were significantly lower during active when compared with passive recovery in moderately trained hockey players. These data demonstrate that active recovery at a work rate corresponding to 28 % of VO(2)max increases total work achieved during repeated WAnT when compared with passive recovery in sedentary subjects and moderately trained hockey players.

  14. CAD/CAM complete dentures: a review of two commercial fabrication systems.

    PubMed

    Kattadiyil, Mathew T; Goodacre, Charles J; Baba, Nadim Z

    2013-06-01

    The use of computer-aided design and computer-aided manufacturing (CAD/CAM) has become available for complete dentures through the AvaDent and Dentca systems. AvaDent uses laser scanning and computer technology. Teeth are arranged and bases formed using proprietary software.The bases are milled from prepolymerized pucks of resin. Dentca uses computer software to produce virtual maxillary and mandibular edentulous ridges, arrange the teeth and form bases. The dentures are fabricated using a conventional processing technique.

  15. Ka- and W-band PM-HFET DRO's

    NASA Astrophysics Data System (ADS)

    Wenger, J.; Guettich, U.

    1993-06-01

    Dielectric resonator stabilized oscillators have been designed, fabricated, and investigated. The oscillators consist of microstrip matching and biasing circuits on alumina substrate, a dielectric resonator puck, and a low-noise quarter-micron InGaAs-GaAs pseudomorphic (PM) HFET as the active device. At 37 GHz and 81 GHz, output powers of 10 dBm and 0 dBm have been measured. The phase noise of the Ka-band and W-band oscillators has been determined to be -97 dBc/Hz at 100 kHz and -90 dBc/Hz at 1 MHz off carrier, respectively.

  16. Flight Experiments On Energy Scaling For In-Space Laser Propulsion

    SciTech Connect

    Scharring, Stefan; Eckel, Hans-Albert; Wollenhaupt, Eric; Roeser, Hans-Peter

    2010-05-06

    As a preparatory study on space-borne laser propulsion, flight experiments with a parabolic thruster were carried out on an air cushion table. The thruster was mounted like a sail on a puck, allowing for laser-driven motion in three degrees of freedom (3 DOF) in artificial weightlessness. Momentum coupling is derived from point explosion theory for various parabolic thruster geometries with respect to energy scaling issues. The experimental data are compared with theoretical predictions and with results from vertical free flights. Experimental results for the air-breakdown threshold and POM ablation inside the thruster are compared with fluence data from beam propagation modeling.

  17. Onset sequencing of selected lip muscles in stutterers and nonstutterers.

    PubMed

    Guitar, B; Guitar, C; Neilson, P; O'Dwyer, N; Andrews, G

    1988-03-01

    The present study examined lip muscle activity during the speech production of stutterers and fluent speakers to provide information about the nature of stuttering blocks. Depressor Anguli Oris (DAO) and Depressor Labii Inferioris (DLI) were recorded, using hooked-wire electromyography (EMG), in 3 stutterers and 3 nonstutterers during productions of the words "peek", "puck", and "pack." EMG records indicated that nonstutterers activated DAO prior to DLI for production of the initial/p/. Stutterers frequently reversed this sequence of onset, particularly when they stuttered. Results are discussed in terms of mistiming versus anticipatory hypertension hypotheses about stuttering.

  18. Shock Initiation of Energetic Materials at Different Initial Temperatures

    SciTech Connect

    Urtiew, P A; Tarver, C M

    2005-01-14

    Shock initiation is one of the most important properties of energetic materials, which must transition to detonation exactly as intended when intentionally shocked and not detonate when accidentally shocked. The development of manganin pressure gauges that are placed inside the explosive charge and record the buildup of pressure upon shock impact has greatly increased the knowledge of these reactive flows. This experimental data, together with similar data from electromagnetic particle velocity gauges, has allowed us to formulate the Ignition and Growth model of shock initiation and detonation in hydrodynamic computer codes for predictions of shock initiation scenarios that cannot be tested experimentally. An important problem in shock initiation of solid explosives is the change in sensitivity that occurs upon heating (or cooling). Experimental manganin pressure gauge records and the corresponding Ignition and Growth model calculations are presented for two solid explosives, LX-17 (92.5 % triaminotrinitrobenzene (TATB) with 7.5 % Kel-F binder) and LX-04 (85 % octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX) with 15 % Viton binder) at several initial temperatures.

  19. The Piece Wise Linear Reactive Flow Model

    SciTech Connect

    Vitello, P; Souers, P C

    2005-08-18

    For non-ideal explosives a wide range of behavior is observed in experiments dealing with differing sizes and geometries. A predictive detonation model must be able to reproduce many phenomena including such effects as: variations in the detonation velocity with the radial diameter of rate sticks; slowing of the detonation velocity around gentle corners; production of dead zones for abrupt corner turning; failure of small diameter rate sticks; and failure for rate sticks with sufficiently wide cracks. Most models have been developed to explain one effect at a time. Often, changes are made in the input parameters used to fit each succeeding case with the implication that this is sufficient for the model to be valid over differing regimes. We feel that it is important to develop a model that is able to fit experiments with one set of parameters. To address this we are creating a new generation of models that are able to produce better fitting to individual data sets than prior models and to simultaneous fit distinctly different regimes of experiments. Presented here are details of our new Piece Wise Linear reactive flow model applied to LX-17.

  20. A frictional work predictive method for the initiation of solid high explosives from low-pressure impacts

    SciTech Connect

    Chidester, S.K.; Green, L.G.; Lee, C.G.

    1993-07-01

    The goal of these tests was to provide information that would aid in the prediction of HE response in accident situations where the initiating stimulus was less than that required for direct shock initiation. Before these tests were run, a prediction of threshold impact velocity was made (70m/s) using a rough average of previously reported threshold factional work from skid tests (1 cal/cm{sub 2}) and the experimental value for coefficient of friction of 0.5({plus_minus}) measured in the same tests for PBX-9404. The actual testing proved the threshold impact velocity to be much less, and the pretest prediction was not only wrong, it was not conservative. This work presents a methodology for more accurately predicting the reaction threshold for HE involved in an accident such as an airplane crash or a severe land transportation accident. The main focus of this work is on LX-10-1 (94.5% 5.5% Viton A binder, density 1.86g/cm{sup 3}). Additional work was done on LX-17 (92.5% TATB, 7.5% KelF binder, density 1.90g/cm{sub 3}), a very insensitive explosive. The explicit two-dimensional finite element code, DYNA2D, was used to model the tests and predict the HE response. The finite element mesh of the projectile and target were generated using MAZE. The post-processing of the DYNA2D analysis was done with ORION.

  1. Dynamic Characterization of Mock Explosive Material Using Reverse Taylor Impact Experiments

    SciTech Connect

    Ferranti, L; Gagliardi, F J; Cunningham, B J; Vandersall, K S

    2010-03-25

    The motivation for the current study is to evaluate the dynamic loading response of an inert mock explosive material used to replicate the physical and mechanical properties of LX-17-1 and PBX 9502 insensitive high explosives. The evaluation of dynamic material parameters is needed for predicting the deformation behavior including the onset of failure and intensity of fragmentation resulting from high velocity impact events. These parameters are necessary for developing and validating physically based material constitutive models that will characterize the safety and performance of energetic materials. The preliminary study uses a reverse Taylor impact configuration that was designed to measure the dynamic behavior of the explosive mock up to and including associated fragmentation. A stationary rod-shaped specimen was impacted using a compressed-gas gun by accelerating a rigid steel anvil attached to a sabot. The impact test employed high-speed imaging and velocity interferometry diagnostics for capturing the transient deformation of the sample at discrete times. Once established as a viable experimental technique with mock explosives, future studies will examine the dynamic response of insensitive high explosives and propellants.

  2. Materials and Sensor R&D to Transform the Nuclear Stockpile: Livermore?s Transformational Materials Initiative

    SciTech Connect

    Maxwell, R; Fried, L; Campbell, G; Saab, A; Kotovsky, J; Carter, C; Chang, J

    2009-10-11

    As the nation's nuclear weapons age and the demands placed on them change, significant challenges face the nuclear stockpile. Risks include material supply issues, ever-increasing lifecycle costs, and loss of technical expertise across the weapons complex. For example, non-nuclear materials are becoming increasingly difficult to replace because manufacturing methods and formulations have evolved in such a way as to render formerly available materials unprofitable, unsafe, or otherwise obsolete. Subtle formulation changes in available materials that occur without the knowledge of the weapons community for proprietary reasons have frequently affected the long-term performance of materials in the nuclear weapon environment. Significant improvements in performance, lifetime, or production cost can be realized with modern synthesis, modeling, and manufacturing methods. For example, there are currently supply and aging issues associated with the insensitive high explosive formulations LX-17 and PBX 9502 that are based on triaminotrinitrobenzene (TATB) and Kel-F, neither of which are commercially available today. Assuring the reliability of the stockpile through surveillance and regularly scheduled Life Extension Programs is an increasingly expensive endeavor. Transforming our current stockpile surveillance--a system based on destructive testing of increasingly valuable assets--to a system based on embedded sensors has a number of potential advantages that include long-term cost savings, reduced risk associated with asset transportation, state-of-health assessments in the field, and active management of the stockpile.

  3. Initiation Pressure Thresholds from Three Sources

    SciTech Connect

    Souers, P C; Vitello, P

    2007-02-28

    Pressure thresholds are minimum pressures needed to start explosive initiation that ends in detonation. We obtain pressure thresholds from three sources. Run-to-detonation times are the poorest source but the fitting of a function gives rough results. Flyer-induced initiation gives the best results because the initial conditions are the best known. However, very thick flyers are needed to give the lowest, asymptotic pressure thresholds used in modern models and this kind of data is rarely available. Gap test data is in much larger supply but the various test sizes and materials are confusing. We find that explosive pressures are almost the same if the distance in the gap test spacers are in units of donor explosive radius. Calculated half-width time pulses in the spacers may be used to create a pressure-time curve similar to that of the flyers. The very-large Eglin gap tests give asymptotic thresholds comparable to extrapolated flyer results. The three sources are assembled into a much-expanded set of near-asymptotic pressure thresholds. These thresholds vary greatly with density: for TATB/LX-17/PBX 9502, we find values of 4.9 and 8.7 GPa at 1.80 and 1.90 g/cm{sup 3}, respectively.

  4. Vertical anisotropic microfibers for a gecko-inspired adhesive.

    PubMed

    Tamelier, John; Chary, Sathya; Turner, Kimberly L

    2012-06-12

    Geckos are able to adhere strongly and release easily from surfaces because the structurally anisotropic fibers on their toes naturally exhibit force anisotropy based on the direction of articulation. Here, semicircular fibers, with varying amounts of contact area on the two faces, are investigated to ascertain whether fiber shape can be used to gain anisotropy in shear and shear adhesion forces. Testing of 10-μm-diameter polydimethylsiloxane (PDMS) fibers against a 4-mm-diameter flat glass puck show that shear and shear adhesion forces were two to five times greater when in-plane movement caused the flat face, rather than the curved face, of the fiber to come in contact with the glass puck. The directional adhesion and shear force anisotropy results are close to theoretical approximations using the Kendall peel model and clearly demonstrate how fiber shape may be used to influence the properties of the adhesive. This result has broad applicability, and by combining the results shown here with other current vertical and angled designs, synthetic adhesives can be further improved to behave more like their natural counterparts.

  5. WRAP low level waste (LLW) glovebox operational test report

    SciTech Connect

    Kersten, J.K.

    1998-02-19

    The Low Level Waste (LLW) Process Gloveboxes are designed to: receive a 55 gallon drum in an 85 gallon overpack in the Entry glovebox (GBIOI); and open and sort the waste from the 55 gallon drum, place the waste back into drum and relid in the Sorting glovebox (GB 102). In addition, waste which requires further examination is transferred to the LLW RWM Glovebox via the Drath and Schraeder Bagiess Transfer Port (DO-07-201) or sent to the Sample Transfer Port (STC); crush the drum in the Supercompactor glovebox (GB 104); place the resulting puck (along with other pucks) into another 85 gallon overpack in the Exit glovebox (GB 105). The status of the waste items is tracked by the Data Management System (DMS) via the Plant Control System (PCS) barcode interface. As an item is moved from the entry glovebox to the exit glovebox, the Operator will track an items location using a barcode reader and enter any required data on the DMS console. The Operational Test Procedure (OTP) will perform evolution`s (described below) using the Plant Operating Procedures (POP) in order to verify that they are sufficient and accurate for controlled glovebox operation.

  6. Molecular Adsorber Coating

    NASA Technical Reports Server (NTRS)

    Straka, Sharon; Peters, Wanda; Hasegawa, Mark; Hedgeland, Randy; Petro, John; Novo-Gradac, Kevin; Wong, Alfred; Triolo, Jack; Miller, Cory

    2011-01-01

    A document discusses a zeolite-based sprayable molecular adsorber coating that has been developed to alleviate the size and weight issues of current ceramic puck-based technology, while providing a configuration that more projects can use to protect against degradation from outgassed materials within a spacecraft, particularly contamination-sensitive instruments. This coating system demonstrates five times the adsorption capacity of previously developed adsorber coating slurries. The molecular adsorber formulation was developed and refined, and a procedure for spray application was developed. Samples were spray-coated and tested for capacity, thermal optical/radiative properties, coating adhesion, and thermal cycling. Work performed during this study indicates that the molecular adsorber formulation can be applied to aluminum, stainless steel, or other metal substrates that can accept silicate-based coatings. The coating can also function as a thermal- control coating. This adsorber will dramatically reduce the mass and volume restrictions, and is less expensive than the currently used molecular adsorber puck design.

  7. Rings and Satellites of Uranus: Colorful and Not So Dark

    NASA Astrophysics Data System (ADS)

    Karkoschka, Erich

    1997-02-01

    Photometric properties of nine uranian satellites and four rings, based on six Hubble Space Telescope images taken in 1995, are presented. Derived albedos are consistent with previous data taken at the same phase angle of 1°, but inconsistent with most Voyager-based estimates extrapolated from observations at phase angles above 15°. The shape of phase functions in the range 1-90° is similar to that of asteroids. Darker surfaces have steeper phase functions than brighter ones, except for the four brightest satellites, which have the same phase function. Puck's geometric albedo in the visible is 0.11 ± 0.015, much larger than the Voyager-based value of 0.074 ± 0.008. The satellites smaller than Puck may be 10% larger than Voyager-based estimates. Ring particles have a geometric albedo of 0.061 ± 0.006, much larger than the Voyager-based value of 0.032 ± 0.003. The longitudinal variation of brightness of the ɛ ring indicates that the mean separation of particles in the ring is four to five times their diameter. While the uranian rings and satellites seemed to be all gray heretofore, the wide wavelength range of this study, 340-910 nm, detected their subtle, distinct colors. Rings and the minor satellites are brown, Miranda is blue, Umbriel is red, and Ariel, Titania, and Oberon are yellow. Rings and minor satellites belong spectrally to M-type asteroids.

  8. Geology of the Uranian satellites

    NASA Technical Reports Server (NTRS)

    Croft, S. K.; Soderblom, L. A.

    1991-01-01

    A geological analysis of six of the Uranus satellites observed in detail by Voyager 2 is presented. All of the satellites except the smallest, Puck, show evidence of cryovolcanic resurfacing: global on the largest four satellites, local in the spectacular coronae on Miranda. The cryovolcanic materials exhibit a range of albedos and morphologies, which are interpreted to reflect a variety of compositions and conditions of eruption at least as complex as those which occur on earth. Eruptions are predominantly large fissure flows that produce extensive flood deposits. Possible evidence of small circular vents and cryoclastic volcanic activity is seen on Miranda and Ariel. All of the satellites except Puck also have extensive sets of grabens and riftlike canyons that show remarkable similarity of pattern: intersection sets trending roughly NW-SW and NE-SW in the low latitudes grading into E-W trends near the poles. As a group, the Uranian satellites are somewhat more active geologically than similarly sized Saturnian satellites.

  9. The Plutonium Transition from Nuclear Weapons to Crypt

    SciTech Connect

    Gray, L.W.

    2000-03-14

    With the end of the ''Cold War'' thousands of nuclear warheads are being dismantled. The National Academy of Sciences termed this growing stockpile of plutonium and highly enriched uranium ''a clear and present danger'' to international security. DOE/MD selected a duel approach to plutonium disposition--burning MOX fuel in existing reactors and immobilization in a ceramic matrix surrounded by HLW glass. MOX material will be pits and clean metal. The challenges come with materials that will be transferred to Immobilization--these range from engineered materials to residues containing < 30% Pu. Impurity knowledge range from guesses to actual data. During packaging, sites will flag ''out of the ordinary'' containers for characterized. If the process history is lost, characterization cost will escalate rapidly. After two step blending and ceramic precursor addition, cold press and sintering will form 0.5-kg ceramic pucks containing {le}50 g Pu. Pucks will be sealed in cans, placed into magazines, then into HLW canisters; these canisters will be filled with HLW glass prior to being transported to the HLW repository. The Immobilization Program must interface with DP, EM, RW, and NN. Overlaid on top of these interfaces are the negotiations with the Russians.

  10. OGC standards for end-to-end sensor network integration

    NASA Astrophysics Data System (ADS)

    Headley, K. L.; Broering, A.; O'Reilly, T. C.; Toma, D.; Del Rio, J.; Bermudez, L. E.; Zedlitz, J.; Johnson, G.; Edgington, D.

    2010-12-01

    technology, and can communicate with any sensor whose protocol can be described by a SID. The SID interpreter transfers retrieved sensor data to a Sensor Observation Service, and transforms tasks submitted to a Sensor Planning Service to actual sensor commands. The proposed SWE PUCK protocol complements SID by providing a standard way to associate a sensor with a SID, thereby completely automating the sensor integration process. PUCK protocol is implemented in sensor firmware, and provides a means to retrieve a universally unique identifer, metadata and other information from the device itself through its communication interface. Thus the SID interpreter can retrieve a SID directly from the sensor through PUCK protocol. Alternatively the interpreter can retrieve the sensor’s SID from an external source, based on the unique sensor ID provided by PUCK protocol. In this presentation, we describe the end-to-end integration of several commercial oceanographic instruments into a sensor network using PUCK, SID and SWE services. We also present a user-friendly, graphical tool to generate SIDs and tools to visualize sensor data.

  11. Mandatory mouthguard rules for high school athletes in the United States.

    PubMed

    Mills, Stephen C

    2015-01-01

    High school athletes seem particularly predisposed to dental injury, but athletic mouthguards have an excellent track record of success in reducing the severity and incidence of dental injuries in sports. Therefore, it has been suggested that mouthguards be made mandatory for high school athletes who participate in sports with risk of injury. The National Federation of State High School Associations currently recommends that mouthguards be mandated for high school football, lacrosse, ice hockey, and field hockey players as well as for wrestlers who are wearing orthodontic appliances. Different states have tried to mandate additional sports with varying degrees of success. This article summarizes the process that leads to rule changes for high school athletes at the national level and discusses the history of 4 states--Minnesota, Maine, New Hampshire, and Massachusetts--that have tried to mandate mouthguards for different sports. Common complaints that lead to the cessation of mouthguard rules, such as speech considerations, breathing ability, and cleanliness, are discussed.

  12. Gender Difference in Fatigue Index and its Related Physiology.

    PubMed

    Hanjabam, Barun; Kailashiya, Jyotsna

    2015-01-01

    Fatigue index exhibits gender difference. This study was carried out to compare fatigue index of young, national level male and female field hockey players; and to explore physiological variables contributing to this difference. We measured running-based anaerobic sprint fatigue index and selected physiological parameters in male and female players matched for age, duration of training, diet, habitual physical activity, body weight and BMI. The male hockey players showed lower resistance to repeated sprints fatigue than the female players. Body weight, BMI and power variables positively correlated to fatigue index in both sexes; while lean body mass and age in males only, and body fat % in females only were found to be correlated to fatigue index. Difference in lean body mass, body fat %, strength and anaerobic power might be responsible for gender difference in intermittent & repeated sprints fatigue index observed in studied players.

  13. Using Masculine Capital to Understand the Role of a Sport Program in the Lives of Men From a Western Canadian Inner City.

    PubMed

    Holt, Nicholas L; Scherer, Jay; Koch, Jordan

    2015-10-01

    The purpose of this study was to examine the role of a sport program in the lives of homeless men with severe mental illnesses and addictions. Interviews were conducted with eight men who attended a floor hockey program, and data examined using categorical-content narrative methodology. Five themes captured the role of the floor hockey program in the men's lives: (a) relationships with program leader, (b) therapy, (c) community, (d) action, and (e) achievement. These themes were interpreted using theories of masculinity (Connell, 1995; Gough, 2014). Relationships with the program leader and other men, and ways in which they were allowed to play with physicality, provided opportunities to accumulate masculine capital (i.e., ways in which competence in traditionally masculine behaviors provides masculine credit). Practically, the findings suggest that sport program delivery for men such as those in this study can be enhanced by providing opportunities for accruing masculine capital.

  14. Scaling Robotic Displays: Visual and Multimodal Options for Navigation by Dismounted Soldiers

    DTIC Science & Technology

    2009-01-01

    8/98) Prescribed by ANSI Std. Z39.18 iii Contents List of Figures v List of Tables v Acknowledgments vi 1. Introduction 1 1.1 Background...need to manage the tasks in such a way as to maximize the composite score. After training, the Soldiers completed the SynWin trial and scores for each...in Complex Environment Performance, D. de Waard , G. Hockey, P. Nickel, K. Brookhuis, Eds.; Europe chapter of the Human Factors and Ergonomics

  15. KSC-04PD-1317

    NASA Technical Reports Server (NTRS)

    2004-01-01

    KENNEDY SPACE CENTER, FLA. In the Orbiter Processing Facility, Jay Feaster, general manager of the National Hockey League 2004 Champions Tampa Bay Lightning, displays the Stanley Cup. At right is KSC Deputy Director Woodrow Whitlow. The cup was also briefly available for viewing by employees in the KSC Training Auditorium. Feaster brought the cup to KSC while on a tour. The Stanley Cup weighs 35 pounds and is more than 100 years old. The Lightning will be added to the cup in September.

  16. Proceedings of Two Symposia on Nondestructive Testing of Tires

    DTIC Science & Technology

    1978-05-01

    REGISTRATION Ballroom , The Holiday Inn Cascade, Akron, Ohio CONVENE MEETING Paul E. J. Vogel, Army Materials and Mechanics Research Center, Watertown...we in- vite the family to go to the Coliseum to a hockey or basketball game. In the winter, we have our scholarship dance . This year it’s...ceiling with big dollar signs dancing in their eyes like proverbial sugar plums. I’m sorry but again money, unfortunately, rears its ugly head. As

  17. Workload Transition: Implications for Individual and Team Performance

    DTIC Science & Technology

    1993-01-01

    fatigue were unrelated to the duration of flights performed at night in the Kuiper Airborne Observatory of the National Aeronautics and Space...continuous noise when required to monitor only a single stimulus source (Blackwell and Belt . 1971; Davies and Hockey, 1966: Jerison, 1959a; Poulton and...Lehr 1962 Vigilance performance as a function of paired monitoring, Journal of Applied Psychology 46i341-343, Blackwell, P1., and J.A. Belt 197 1

  18. THE USE OF ACETIC ACID IONTOPHORESIS IN THE MANAGEMENT OF A SOFT TISSUE INJURY

    PubMed Central

    Ebaugh, David

    2010-01-01

    Background: Contusions are common injuries that occur in athletics. If repeated, complications like myositis ossificans can occur. This case describes the examination and treatment of an athlete with an acute soft tissue injury. Objective: To describe the treatment approach used with a hockey player who sustained a soft tissue injury in his upper extremity. Case Description: A 19 year old male sustained a soft tissue injury to his upper arm while playing hockey. The athlete complained of pain rated a 2-3 out of 10. He had a well circumscribed, firm, 8 by 5 centimeter palpable mass present along the lateral arm, and was able to passively flex his elbow from 56° to 135°, demonstrating a 56° loss of elbow extension. Functionally, he was able to perform most activities of daily living, but he was unable to play hockey. Over 29 days, the athlete was treated one time with pulsed ultrasound and ice and nine times with iontophoresis using a 2% acetic acid solution. Additionally, the athlete performed pain-free active range of motion exercises for the elbow. Outcome: Following treatment, the athlete's pain resolved, the palpable mass disappeared, and his passive range of motion at the elbow was 0° to 135°. Most importantly, the athlete was able to resume playing hockey. Discussion: Acetic acid iontophoresis may be a successful intervention for soft tissue injuries of the upper extremity. In this case, it appeared helpful in decreasing the athlete's impairments and contributed to quicker resumption of all functional activities in less time than previously reported in the literature using traditional treatment interventions. PMID:21655380

  19. Summary and agreement statement of the 2nd International Conference on Concussion in Sport, Prague 2004

    PubMed Central

    McCrory, P; Johnston, K; Meeuwisse, W; Aubry, M; Cantu, R; Dvorak, J; Graf-Baumann, T; Kelly, J; Lovell, M; Schamasch, P

    2005-01-01

    In November 2001, the 1st International Symposium on Concussion in Sport was held in Vienna, Austria to provide recommendations for the improvement of safety and health of athletes who suffer concussive injuries in ice hockey, football (soccer), and other sports. The 2nd International Symposium on Concussion in Sport was organised by the same group and held in Prague, Czech Republic in November 2004. It resulted in a revision and update of the Vienna consensus recommendations, which are presented here.

  20. Summary and agreement statement of the 2nd International Conference on Concussion in Sport, Prague 2004

    PubMed Central

    McCrory, P; Johnston, K; Meeuwisse, W; Aubry, M; Cantu, R; Dvorak, J; Graf-Baumann, T; Kelly, J; Lovell, M; Schamasch, P

    2005-01-01

    In November 2001, the 1st International Symposium on Concussion in Sport was held in Vienna, Austria to provide recommendations for the improvement of safety and health of athletes who suffer concussive injuries in ice hockey, football (soccer), and other sports. The 2nd International Symposium on Concussion in Sport was organised by the same group and held in Prague, Czech Republic in November 2004. It resulted in a revision and update of the Vienna consensus recommendations, which are presented here. PMID:15793085

  1. Exposure to Elevated Carbon Monoxide Levels at an Indoor Ice Arena--Wisconsin, 2014.

    PubMed

    Creswell, Paul D; Meiman, Jon G; Nehls-Lowe, Henry; Vogt, Christy; Wozniak, Ryan J; Werner, Mark A; Anderson, Henry

    2015-11-20

    On December 13, 2014, the emergency management system in Lake Delton, Wisconsin, was notified when a male hockey player aged 20 years lost consciousness after participation in an indoor hockey tournament that included approximately 50 hockey players and 100 other attendees. Elevated levels of carbon monoxide (CO) (range = 45 ppm-165 ppm) were detected by the fire department inside the arena. The emergency management system encouraged all players and attendees to seek medical evaluation for possible CO poisoning. The Wisconsin Department of Health Services (WDHS) conducted an epidemiologic investigation to determine what caused the exposure and to recommend preventive strategies. Investigators abstracted medical records from area emergency departments (EDs) for patients who sought care for CO exposure during December 13-14, 2014, conducted a follow-up survey of ED patients approximately 2 months after the event, and conducted informant interviews. Ninety-two persons sought ED evaluation for possible CO exposure, all of whom were tested for CO poisoning. Seventy-four (80%) patients had blood carboxyhemoglobin (COHb) levels consistent with CO poisoning; 32 (43%) CO poisoning cases were among hockey players. On December 15, the CO emissions from the propane-fueled ice resurfacer were demonstrated to be 4.8% of total emissions when actively resurfacing and 2.3% when idling, both above the optimal range of 0.5%-1.0%. Incomplete fuel combustion by the ice resurfacer was the most likely source of elevated CO. CO poisonings in ice arenas can be prevented through regular maintenance of ice resurfacers, installation of CO detectors, and provision of adequate ventilation.

  2. [Athletic pubalgia and hip impingement].

    PubMed

    Berthaudin, A; Schindler, M; Ziltener, J-L; Menetrey, J

    2014-07-16

    Athletic pubalgia is a painful and complex syndrom encountered by athletes involved in pivoting and cutting sports such as hockey and soccer. To date, there is no real consensus on the criteria for a reliable diagnostic, the different investigations, and the appropriate therapy. Current literature underlines intrinsic and extrinsic factors contributing to athletic pubalgia. This review article reports upon two novelties related to the issue: the importance and efficience of prevention program and the association of femoro-acetabular impingement with the pubalgia.

  3. Dose-response analysis of infants prenatally exposed to methyl mercury: An application of a single compartment model to single-strand hair analysis

    SciTech Connect

    Cox, C.; Clarkson, T.W.; Marsh, D.O.; Amin-Zaki, L.; Tikriti, S.; Myers, G.G. )

    1989-08-01

    A new method of estimating fetal exposure is used in a dose-response analysis of data from the 1971 outbreak of methyl mercury poisoning in rural Iraq. An X-ray fluorescence instrument for the measurement of single strands of human hair was employed to obtain longitudinal profiles recapitulating fetal exposure. Logit and hockey-stick models as well as nonparametric smoothing are used to describe data on delayed development and central nervous system abnormality.

  4. Reanalysis of dose-response data from the Iraqi methylmercury poisoning episode

    SciTech Connect

    Crump, K.; Clewell, H.; Gearhart, J.

    1995-08-01

    Applying a hockey stick parametric dose-response model to data on late or retarded development in Iraqi children exposed in utero to methylmercury, with mercury (Hg) exposure characterized by the peak Hg concentration in mothers` hair during pregnancy, Cox et al. calculated the {open_quotes}best statistical estimate{close_quotes} of the threshold for health effects as 10 ppm Hg in hair with a 95% range of uncertainty of between 0 and 13.6 ppm. A new application of the hockey stick model to the Iraqi data shows, however, that the statistical upper limit of the threshold based on the hockey stick model could be as high as 255 ppm. Futhermore, the maximum likelihood estimate of the threshold using a different parametric model is virtually zero. These and other analyses demonstrate that threshold estimates based on parametric models exhibit high statistical variability and model dependency, and are highly sensitive to the precise definition of an abnormal response. Consequently, they are not a reliable basis for setting a reference dose (RfD) for methylmercury. Benchmark analyses and statistical analyses useful for deriving NOAELs are also presented. We believe these latter analyses-particularly the benchmark analyses-generally form a sounder basis for determining RfDs than the type of hockey stick analysis presented by Cox et al. However, the acute nature of the exposures, as well as other limitations in the Iraqi data suggest that other data may be more appropriate for determining acceptable human exposures to methylmercury. 24 refs., 5 figs., 2 tabs.

  5. The Human-Information Workspace (HI-Space): Ambient Table Top Entertainment

    SciTech Connect

    Cowell, Andrew J.; May, Richard A.; Cramer, Nick O.; Matthias Rauterberg

    2004-09-01

    This paper introduces the Human Information Workspace (HISpace) as a test-bed for evaluating new information exploration mechanisms. In moving from dated interaction devices and small computer monitors, we aim to utilize more natural surfaces such as tables and walls as our interaction space. In testing our theories, we have produced a number of gaming applications as test cases. Here, we report on our most popular application, Virtual Hockey.

  6. [Incidence and type of injuries in icehockey].

    PubMed

    Mang, W R

    1977-01-27

    This investigation analyzes 79 injuries of players of the German Ice-Hockey-National-Team which happened in 37 international games from 1974 to 1976. 36% of the injuries are caused by the stick, which corresponds to the reports of literature. Serious injuries, especially head injuries can be reduced if the following rules are observed: Good conditioning of the players, equipment according to regulations with helm and mouth protection during training and game, exact control of the game by the referees.

  7. Prevention of sports-related eye injury.

    PubMed

    Stock, J G; Cornell, F M

    1991-08-01

    Sports-related eye injury is an important cause of vision loss. Many eye injuries can be prevented through the supervision of play, the enforcement of game rules and the use of eye protective devices. State-of-the-art eye protective devices incorporate highly impact-resistant optical material, usually polycarbonate lenses, in a sturdy frame. Protective devices are available for use in racquet sports, baseball, basketball, football, ice hockey and other sports.

  8. Isolated Teres Major Rupture: A case report with a suggested dedicated imaging protocol and review of the literature

    PubMed Central

    Fitzpatrick, Darren; Cagle, Paul; Flatow, Evan

    2016-01-01

    Isolated injuries to the teres major muscle occur in competitive sporting activities such as baseball pitching, hockey and tennis. We report a similar event of a physically fit man sustaining an isolated teres major rupture while waterskiing. Non-operative management was chosen, with pain resolution and no appreciable functional limitations at follow up. Because teres major muscle injury was suspected at the time of imaging, we present a dedicated imaging protocol to optimize assessment for teres major injury. PMID:27200170

  9. BEETLE II: A System for Tutoring and Computational Linguistics Experimentation

    DTIC Science & Technology

    2010-07-01

    Rosé and Torrey , 2005). Having a system that al- lows more unrestricted language input will pro- vide a more balanced comparison. We are also...Ann Hockey, Oliver Lemon, Ellen Campana, Laura Hiatt, Gregory Aist, James Hieronymus, Alexander Gruenstein, and John Dowding. 2003. Targeted help for...Florida, May. C.P. Rosé and C. Torrey . 2005. Interactivity versus ex- pectation: Eliciting learning oriented behavior with tutorial dialogue systems

  10. Life Support and Protection Requirements for the Head/Neck Region of Navy Aircrewmen

    DTIC Science & Technology

    1986-12-01

    head is a hard-shell helmet . This is the current solution of i * choice for such diverse activities as football , motorcycling, ice hockey, and military...su~t, flotation gear, etc., outweigh the advantages. In addition, programs are afoot to reconfigure the protective helmet to accommodate more...additions to the protective helmet , penalties can only increase. Problems of comfort, fatigue, and restriction of movement will be exacerbated. -The

  11. Incidence and severity of reported acute sports injuries in 35 sports using insurance registry data.

    PubMed

    Åman, M; Forssblad, M; Henriksson-Larsén, K

    2016-04-01

    Acute injuries in sport are still a problem where limited knowledge of incidence and severity in different sports at national level exists. In Sweden, 80% of the sports federations have their mandatory injury insurance for all athletes in the same insurance company and injury data are systematically kept in a national database. The aim of the study was to identify high-risk sports with respect to incidence of acute and severe injuries in 35 sports reported to the database. The number and incidences of injuries as well as injuries leading to permanent medical impairment (PMI) were calculated during 2008-2011. Each year approximately 12,000 injuries and 1,162,660 licensed athletes were eligible for analysis. Eighty-five percent of the injuries were reported in football, ice hockey, floorball, and handball. The highest injury incidence as well as PMI was in motorcycle, handball, skating, and ice hockey. Females had higher risk of a PMI compared with males in automobile sport, handball, floorball, and football. High-risk sports with numerous injuries and high incidence of PMI injuries were motorcycle, handball, ice hockey, football, floorball, and automobile sports. Thus, these sports ought to be the target of preventive actions at national level.

  12. A behavioural dynamic model of the relative age effect.

    PubMed

    Pierson, Kawika; Addona, Vittorio; Yates, Philip

    2014-01-01

    The relationship between date of birth and success in a variety of sports, including hockey, is well established. This phenomenon is known as the relative age effect (RAE). We model the RAE in Canadian youth hockey as a positive feedback loop where an initial age advantage is reinforced through additional training and playing opportunities based on perceived skill superiority. The same causal mechanism leads to a higher quit rate for relatively younger players. Our model effectively replicates the birth month distribution of Canadian National Hockey League players (R2 = 86.79%) when driven by Canadian birth distributions. We use this model to evaluate three policies that aim to lessen the RAE. All of the policies reduce the RAE with a significant delay. The most effective policy is a combination of providing additional support to age disadvantaged children and rotating the cut-off date for youth leagues between January 1st and July 1st annually. In equilibrium, this approach leads to a 96% reduction in the RAE compared to the base case.

  13. Neutron Screening Measurements of 110 gallon drums at T Plant

    SciTech Connect

    Mozhayev, Andrey V.; Hilliard, James R.; Berg, Randal K.

    2011-01-14

    The Pacific Northwest National Laboratory (PNNL) Nondestructive Assay (NDA) Service Center was contracted to develop and demonstrate a simple and inexpensive method of assaying 110 gallon drums at the Hanford Site’s T-Plant. The drums contained pucks of crushed old drums used for storage of transuranic (TRU) waste. The drums were to be assayed to determine if they meet the criteria for TRU or Low Level Waste (LLW). Because of the dense matrix (crushed steel drums) gamma measurement techniques were excluded and a mobile, configurable neutron system, consisting of four sequentially connected slab detectors was chosen to be used for this application. An optimum measurement configuration was determined through multiple test measurements with californium source. Based on these measurements the initial calibration of the system was performed applying the isotopic composition for aged weapon-grade plutonium. A series of background and blank puck drum measurements allowed estimating detection limits for both total (singles) and coincidence (doubles) counting techniques. It was found that even conservative estimates for minimum detection concentration using singles count rate were lower than the essential threshold of 100 nCi/g. Whereas the detection limit of coincidence counting appeared to be about as twice as high of the threshold. A series of measurements intended to verify the technique and revise the initial calibration obtained were performed at the Waste Receiving and Processing (WRAP) facility with plutonium standards. Standards with a total mass of 0.3 g of plutonium (which is estimated to be equivalent of 100 nCi/g for net waste weight of 300 kg) loaded in the test puck drum were clearly detected. The following measurements of higher plutonium loadings verified the calibration factors obtained in the initial exercise. The revised and established calibration factors were also confirmed within established uncertainties by additional measurements of plutonium

  14. Gaze behaviors of goaltenders under spatial-temporal constraints.

    PubMed

    Panchuk, D; Vickers, J N

    2006-12-01

    It is still not known what underlies successful performance in goaltending. Some studies have reported that advanced cues from the shooter's body (hip, kicking leg or support leg) are most important (Savelsbergh, G. J. P., Williams, A. M., Van der Kamp, J., & Ward, P. (2002). Visual search, anticipation and expertise in soccer goalkeepers. Journal of Sports Sciences, 20, 279-287; Savelsbergh, G. J. P., Williams, A. M., Van der Kamp, J., & Ward, P. (2005). Anticipation and visual search behaviour in expert soccer goalkeepers. Ergonomics, 48, 1686-1697; Williams, A. M., & Burwitz, L. (1993). Advanced cue utilization in soccer. In T. Reilly, J. Clarys, & A. Stibbe (Eds.), Science and football II (pp. 239-243). London, England: E&FN Spon), while others have found that the early tracking of the object prior to and during flight is most critical (Bard, C., & Fleury, M. (1981). Considering eye movement as a predictor of attainment. In: I. M. Cockerill, & W. M. MacGillvary (Eds.), Vision and Sport (pp. 28-41). Cheltenham, England: Stanley Thornes (Publishers) Ltd.). These results are similar to those found in a number of interceptive timing studies (Land, M. F., & McLeod, P. (2000). From eye movements to actions: How batsmen hit the ball. Nature Neuroscience, 3, 1340-1345; Ripoll and Fleurance, 1988; Vickers, J. N., & Adolphe, R. M. (1997). Gaze behaviour during a ball tracking and aiming skill. International Journal of Sports Vision, 4, 18-27). The coupled gaze and motor behavior of elite goaltenders were determined while responding to wrist shots taken from 5 m and 10 m on ice. The results showed that the goalies faced shots that were significantly different in phase durations due to distance (5 versus 10 m), but this was not a factor in making saves. Instead, the ability to stop the puck was dependent on the location, onset and duration of the final fixation/tracking gaze (or quiet eye) prior to initiating the saving action. The relative onset of quiet eye was

  15. Indirect blue light does not suppress nocturnal salivary melatonin in humans in an automobile setting.

    PubMed

    Lerchl, Alexander; Schindler, Carina; Eichhorn, Karsten; Kley, Franziska; Erren, Thomas C

    2009-09-01

    In 2007, the International Agency for Research on Cancer (IARC) classified shift work that involves circadian disruption as being probably carcinogenic to humans (Group 2A). In this context, light exposure during the night plays a key role because it can suppress nocturnal melatonin levels when exposures exceed a certain threshold. Blue light around 464 nm is most effective in suppressing melatonin because of the spectral sensitivity of melanopsin, a recently discovered photopigment in retinal ganglion cells; the axons of these cells project to the suprachiasmatic nucleus, a circadian master clock in the brain. Due to advances in light technologies, normal tungsten light bulbs are being replaced by light-emitting diodes which produce quasi-monochromatic or white light. The objective of this study was to assess whether the light-melanopsin-melatonin axis might be affected in automobiles at night which employ the new generation diodes. To this end, we have tested in an experimental automobile setting whether indirect blue light (lambda(max) = 465 nm) at an intensity of 0.22 or 1.25 lx can suppress salivary melatonin levels in 12 male volunteers (age range 17-27 years) who served as their own controls. Daytime levels were low (2.7 +/- 0.5 pg/mL), and night-time levels without light exposure were high (14.5 +/- 1.1 pg/mL), as expected. Low-intensity light exposures had no significant effect on melatonin levels (0.22 lx: 17.2 +/- 2.8 pg/mL; P > 0.05; 1.25 lx: 12.6 +/- 2.0 pg/mL; P > 0.05). It is concluded that indirect blue light exposures in automobiles up to 1.25 lx do not cause unintentional chronodisruption via melatonin suppression.

  16. Fatigue of LX-14 and LX-19 plastic bonded explosives

    SciTech Connect

    Hoffman, D. M., LLNL

    1998-04-23

    The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively forged projectiles. LX- 19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOW-2, include the Apache helicopter. Loads associated with vibrations and expansion from thermal excursions in field operations may, even at low levels over long time periods, cause flaws, already present in the PBX to grow. Flaws near the explosive/liner interface of a shaped charge can reduce performance. Small flaws in explosives are one mechanism (the hot spot mechanism) proposed for initiation and growth to detonation of PBXs like LX-14, PBXN 5, LX-04 and LX-17 among others. Unlike cast-cured explosives and propellants, PBXs cannot usually be compression molded to full density. Generally, the amount of explosive ignited by a shock wave is approximately equal to the original void volume. Whether or not these flaws or cracks grow during field operations to an extent sufficient to adversely affect the shaped charge performance or increase the vulnerability of the PBX is the ultimate question this effort could address. Currently the fatigue life of LX-14 under controlled conditions is being studied in order to generate its failure stress as a function of the number of fatigue cycles (S- N curve). Proposed future work will address flaw and crack growth and their relationship to hot-spot concentration and explosive vulnerability to shock and/or fragment initiation.

  17. Recent advances in the molten salt technology for the destruction of energetic materials

    SciTech Connect

    Upadhye, R.S.; Watkins, B.E.; Pruneda, C.O.

    1995-11-01

    The DOE has thousands of pounds of energetic materials which result from dismantlement operations at the Pantex Plant. The authors have demonstrated the Molten Salt Destruction (MSD) Process for the treatment of explosives and explosive-containing wastes on a 1.5 kilogram of explosive per hour scale and are currently building a 5 kilogram per hour unit. MSD converts the organic constituents of the waste into non-hazardous substances such as carbon dioxide, nitrogen and water. Any inorganic constituents of the waste, such as binders and metallic particles, are retained in the molten salt. The destruction of energetic material waste is accomplished by introducing it, together with air, into a crucible containing a molten salt, in this case a eutectic mixture of Na, K, and Li carbonates. The following pure component DOE and DoD explosives have been destroyed in LLNL`s experimental unit at their High Explosives Applications Facility (HEAF): ammonium picrate, HMX, K-6, NQ, NTO, PETN, RDX, TATB, and TNT. In addition, the following formulations were also destroyed: Comp B, LX-10, LX-16, LX-17, PBX-9404, and XM46, a US Army liquid gun propellant. In this 1.5 kg/hr unit, the fractions of carbon converted to CO and of chemically bound nitrogen converted to NOx were found to be well below 1T. In addition to destroying explosive powders and molding powders the authors have also destroyed materials that are typical of real world wastes. These include shavings from machined pressed parts of plastic bonded explosives and sump waste containing both explosives and non-explosive debris. Based on the information obtained on the smaller unit, the authors have constructed a 5 kg/hr MSD unit, incorporating LLNL`s advanced chimney design. This unit is currently under shakedown tests and evaluation.

  18. Kinetic Modeling of Slow Energy Release in Non-Ideal Carbon Rich Explosives

    SciTech Connect

    Vitello, P; Fried, L; Glaesemann, K; Souers, C

    2006-06-20

    We present here the first self-consistent kinetic based model for long time-scale energy release in detonation waves in the non-ideal explosive LX-17. Non-ideal, insensitive carbon rich explosives, such as those based on TATB, are believed to have significant late-time slow release in energy. One proposed source of this energy is diffusion-limited growth of carbon clusters. In this paper we consider the late-time energy release problem in detonation waves using the thermochemical code CHEETAH linked to a multidimensional ALE hydrodynamics model. The linked CHEETAH-ALE model dimensional treats slowly reacting chemical species using kinetic rate laws, with chemical equilibrium assumed for species coupled via fast time-scale reactions. In the model presented here we include separate rate equations for the transformation of the un-reacted explosive to product gases and for the growth of a small particulate form of condensed graphite to a large particulate form. The small particulate graphite is assumed to be in chemical equilibrium with the gaseous species allowing for coupling between the instantaneous thermodynamic state and the production of graphite clusters. For the explosive burn rate a pressure dependent rate law was used. Low pressure freezing of the gas species mass fractions was also included to account for regions where the kinetic coupling rates become longer than the hydrodynamic time-scales. The model rate parameters were calibrated using cylinder and rate-stick experimental data. Excellent long time agreement and size effect results were achieved.

  19. Laser cutting of pressed explosives: Revision 1

    SciTech Connect

    Roeske, F., Jr.; Banks, R.E.; Armstrong, J.P.; Feit, M.D.; Lee, R.S.; Perry, M.D.; Stuart, B.C.

    1998-05-04

    We have used a femtosecond laser beam to make cuts through small pressed pellets of six common explosives. The laser system, which produces 100 fs pulses of 820 nm light at a repitition rate of 1 kHz, was intitially developed for cutting metal. The advantage of using a femtosecond laser for cutting is that the cutting process transfers virtually no heat to the material that is being cut and produces almost no waste. We used LX-16 explosive (96% PETN/4% FPC 461 binder) for out intial experiments because PETN is one of the most sensitve of the secondary explosives. In some of the experiments the beam first cut through the HE pellet and then through a stainless steel substrate and in other experiments the beam first cut through the stainless steel and then through the pellet. We also cut through pellets that were not backed by a substrate. No evidence of reaction was observed in any of the LX-16 pellets. In addition to LX-16 we cut pellets of LX-14 (95.5% HMX/4.5% Estane), LX-15 (95% HNS/5% Kel-F), LX-17 (92.5% TATB/7.5% Kel-F), PBX-9407 (94% RDX/6% Exon 461), and pressed TNT with no evidence of reaction. The HE was easily cut at low power levels with one or two sweeps at 0.5 W average power sufficing to cut most of the pellets. There is obvioulsy much more work to be done before laser machining of explosives becomes a reality, but the results of these intitial experiments indicate that laser machining of explosives may be an attractive option for explosives processing.

  20. Simulation of Low Velocity Impact Induced Inter- and Intra-Laminar Damage of Composite Beams Based on XFEM

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Guan, Zhidong; Li, Zengshan

    2017-03-01

    In this paper, the Inter-Fiber Fracture (IFF) criterion of Puck failure theory based on the eXtended Finite Element Method (XFEM) was implemented in ABAQUS code to predict the intra-laminar crack initiation of unidirectional (UD) composite laminate. The transverse crack path in the matrix can be simulated accurately by the presented method. After the crack initiation, the propagation of the crack is simulated by Cohesive Zoom Model (CZM), in which the displacement discontinuities and stress concentration caused by matrix crack is introduced into the finite element (FE) model. Combined with the usage of the enriched element interface, which can be used to simulate the inter-laminar delamination crack, the Low Velocity Impact (LVI) induced damage of UD composite laminate beam with a typical stacking of composite laminates [05/903]S is studied. A complete crack initiation and propagation process was simulated and the numerical results obtained by the XFEM are consistent with the experimental results.