Title: Relation between selected off-ice tests and performance in on-ice Illinois Agility test of ice hockey players between 14-17 years old in Czech elite category. Objectives: The main goal of this thesis was to determine whether the somatotype and selected off-ice tests are significant predictors for performance in the on-ice agility test in ice hockey players in the youth elite category. Methods: The research group consisted 28 ice hockey players (8 forwards and 18 defenders) x̅ = 14,88 ± 0,57. Players played highest youth league during the measurement period. The method of Heath and Carter (1990) was used to determine the somatotype. Squat Jump, Countermovement Jump, Free Arm Countermovement Jump, Sit and Reach, pull-ups and off- ice Illinois Agility with a ball were used as off-ice tests. The Aspin-Welch two-samle T-test with Effect size (ES) Hedges' g was used to evaluate the degree of difference in performance between forwards and defenders. Pearson's correlation coefficient with ES coefficient of determination R2 was applied to determine the tightness of relationships between selected variables. Evaluation of the significance of predictors for performance in on- ice agility tests was performed through multiple regression analysis. The significance of the model was assessed according to the...

Title: Relation between selected off-ice tests, somatotype and performance in on-ice Illinois Agility tests in junior ice hockey players from Czech elite category. Objective: The aim of this thesis was to verify whether the somatotype and off-ice tests are significant predictors for performance in on-ice agility tests in junior ice hockey players from Czech elite category. Methods: The research sample consisted of 32 junior hockey players (17 defenders and 15 forwards) ̅ = 17.64 ± 1.02 from Czech elite category. The Heath and Carter (1990) method for measuring of somatotype was used. The off-ice tests included Squat Jump, Countermovement Jump, Free Arm Countermovement Jump, Broad Jump, Five-Jump test, Sit and Reach, Pull-ups and off-ice Illinois Agility with (small size) ball. Further, on-ice Illinois Agility with puck and Illinois Agility without puck were used as dependent variables. The differences in performance between defenders and forwards were analysed by Aspin-Welch's two-sample T-test with Effect size (ES) Hedges's g. The degree of significance of the predictors for dependent variables in on- ice agility tests was assessed by multiple regression analysis with significance of model at the level of p<0.05 and ES described as adjusted R2 . Results: Comparison of the results achieved by...

The aim of this research was to demonstrate the relationship between variations in summertime surface mass balance of the McMurdo Ice Shelf and atmospheric processes. The approach encompassed a broad range of techniques. An existing energy balance mass balance model was adapted to deal with debris-covered ice surfaces and modified to produce distributed output. Point based surface energy and mass balance for two key surfaces of the ice shelf were linked to different synoptic types that were identified using a manual synoptic classification. The distributed model was initialised with distributed parameters derived from satellite remote sensing and forced with data from a regional climate model. Patterns of summertime surface mass balance produced by the distributed model were assessed against stake measurements and with respect to atmospheric processes. During the summers of 2003-2004 and 2004-2005 an automatic weather station (AWS) was operated on bare and debris-covered ice surfaces of the McMurdo Ice shelf, Antarctica. Surface mass balance was calculated using the energy balance model driven by the data from the AWS and additional data from permanent climate stations. Net mass balance for the measurement period was reproduced reasonably well when validated against directly measured turbulent fluxes, stake measurements, and continuously measured surface height at the AWS. For the bare ice surface net radiation provided the major energy input for ablation, whereas sensible heat flux was a second heat source. Ablation was by both melt (70%) and sublimation (30%). At the debris-covered ice site investigated, it is inferred that the debris cover is sufficient to insulate the underlying ice from ablation. Synoptic weather situations were analysed based on AVHRR composite images and surface pressure charts. Three distinct synoptic situations were found to occur during the summers, these were defined as Type A, low pressure system residing in the Ross Sea Embayment; Type B, anticyclonic conditions across region; and Type C, a trough of low pressure extending into the Ross Sea Embayment. A dependence of surface energy fluxes and mass balance on synoptic situation was identified for the bare ice surface. The distributed model was found to produce spatial patterns of mass balance which compared well with stake measurements. Mass balance patterns show that the McMurdo Ice Shelf was generally ablating in the west, and accumulating in the east during summer. Areas of enhanced ablation were found which were likely to be caused by the surface conditions and topographic effects on the wind field. The mean summertime surface mass balance across the entire ice shelf for the 2003-2004 and 2004-2005 summers were –2.5 mm w.e. and –6.7 mm w.e. respectively. The differences between the two summers are inferred to be a result of more frequent type A conditions occurring during the summer of 2004-2005.

This work aims to study the behavior of the western margin of the Greenland Ice Sheet during a period of pronounced ice retreat roughly 10,000 years ago, after the end of the last glacial period. It explores the efficiency of subglacial erosion, the spatial dynamics of ice retreat, and the rates of ice retreat. To address these questions, I use the radionuclides 10Be and 26Al, which form in rocks due to the bombardment of cosmic rays, only after the rocks have been exposed from underneath retreating ice. These nuclides can be used as a geologic dating technique to explore exposure history. Before applying this dating technique to address geological questions, it was critical to first perform methodological development. My work in the University of Vermont‘s new Cosmogenic Nuclide Laboratory served to improve the precision and efficiency of the pre-existing laboratory methods. New methodological advances ensured that samples from Greenland, which contained only low concentrations of 10Be and 26Al, could be used to yield meaningful results about ice behavior. Cosmogenic nuclide dating was applied at two sites along the ice sheet margin in central-western Greenland. At both of these sites, I collected paired bedrock and boulder samples in a transect normal to and outside of the present-day ice sheet margin. Samples were collected from a variety of elevations at numerous locations along the transects, thus providing three-dimensional coverage of the field area. After isolating the mineral quartz from the rocks, and isolating the elements Be and Al from the quartz, isotopic analysis was performed using accelerator mass spectrometry to quantify the relative abundances of the radionuclides against their respective stable isotopes. The southern study site, Ilulissat, is located on the western coast of Greenland at a latitude of 69N. Much previous work has been conducted here due to the presence of one of the largest ice streams in the northern hemisphere, Jakobshavn Isbræ. My work in Ilulissat demonstrated that subglacial erosion rates were high during previous glacial periods, efficiently sculpting and eroding the landscape. Ice retreat across the land surface began around 10,300 years ago, and the ice sheet retreated behind its present-day margin about 7,600 years ago. Ice retreat occurred at a rate of about 100 meters per year. My work in this area suggests that retreat in the large ice stream set the pace and timing for retreat of the neighboring ice sheet margin. The northern site, Upernavik, is located on the western coast of Greenland at a latitude of 73N. Little research has been conducted here in the past. Unlike in Ilulissat, my work here shows that the ice sheet did not efficiently erode the landscape, especially at high elevations, during previous glacial periods. This is likely because the ice was thinner, and therefore had a colder base, than the ice in Ilulissat. My work suggests that ice cover was lost from this area very rapidly, likely at rates of about 170 meters per year, in a single episode around 11,300 years ago. Comparison between the two study sites reveals that ice characteristics can vary appreciably over relatively small distances.

Syfte Syftet med studien är att undersöka korrelationen mellan cykeltestet "repeated 5 second cycling sprint test" (R5sCST) samt off-ice testet 36 meter upprepade sprinter (OfI) mot on-ice testet 33 meter upprepade sprinter (OnI). Samtidigt vill vi se om R5sCST kan utvärdera skridskosnabbhet samt undersöka om OfI kan användas som en alternativ testmetod med samma syfte. De frågeställningar vi besvarar är, – Finns det en korrelation mellan R5sCST och OnI? - Finns det en korrelation mellan OfI och OnI? – Är R5sCST och OfI relevanta testmetoder för att utvärdera förmågan till upprepade sprinter on-ice? - Finns det andra testvärden som kan förutse snabbhet on-ice? Metod 3 tester har genomförts, ett cykeltest (R5sCST), ett on-ice test (OnI) och ett off-ice test (OfI). Testerna genomfördes på Bosön och i Björkängshallen vid två olika tillfällen, det var 2 dagar mellan testtillfällena. Testtillfälle 1 genomfördes R5sCST och OfI på Bosön, testtillfälle 2 genomfördes OnI i Björkängshallen. 18 stycken ishockeyspelare på junior elitnivå testades. Försökspersonerna (FP) var mellan 16 och 18 år gamla och har en idrottslig bakgrund inom ishockey som motsvarar 11-13 år. Resultat Studien visar att såväl medelvärdena samt de högst uppmätta effekt värdena hos varje FP från R5sCST testet korrelerar med medel- och högsta värden på OnI. Studien visar även en starkare korrelation mellan OfI och OnI. Slutsats Efter genomförd studie kan det konstateras att R5sCST, trots att det inte efterliknar ishockeyns krav fullt ut i arbetstid/vilotid, är ett reliabelt test för att utvärdera snabbhet on-ice. Det framkommer även i studien att OfI har större korrelationer till OnI än vad R5sCST har, vilket innebär att även OfI är ett högst reliabelt test för att utvärdera snabbhet on-ice. Förutom större korrelationer så är även OfI mer lämpat för lag och föreningar att använda sig av då det är enklare att utföra och mindre kostsamt än R5sCST. / <p>Ämneslärarprogrammet, Specialidrott</p>

Cheuk Yeuk Pik. / Summary in Chinese. / Thesis (M.B.A.)--Chinese University of Hong Kong. / Bibliography: leaf 49.

The loss of ice from the Greenland ice sheet is an important contributor to current and future sea level rise occurring due to ongoing changes in the global climate. A significant portion of this ice mass loss comes through the calving of large icebergs at Greenland’s many marine-terminating outlet glaciers. However, the dynamics of calving at these glaciers is currently not well understood, complicating projections of future behaviour of these glaciers and mass loss from the Greenland ice sheet. The use of seismological tools has shown promise as a means of both monitoring and better understanding the dynamics of the calving process at these glaciers. On the global scale, data from the long-standing global seismic network has recorded the occurrence of glacial earthquakes, large long period earthquakes that occur during large calving events at near-grounded outlet glaciers. The occurrence and source parameters of these earthquakes provide insight into the link between glacier calving and climatic and oceanic forcings, as well as information on the large-scale glacier-dynamic conditions under which these major calving events occur. On the more local scale, a deployment of seismometers around an individual glacier has provided insights on the seismic environment of a calving glacier, as well as the more immediate, short-term external drivers of calving events. We consider both local and global seismic data in order to further understanding of the dynamics of the calving process at Greenland outlet glaciers, and find that glacial earthquake production is indicative of a near-grounded terminus at the source glacier. We find that the locations derived from these events are accurate and are sensitive to changes in the calving-front position of the source glacier, and that the active-force azimuths are representative of the orientation of the glacier at the time of calving. We also find that these glaciers are the source of abundant small icequakes, which are strongly tied to the occurrence of major calving events. The small icequakes that occur at Helheim glacier are modulated by semi-diurnal variations in tide height, and potentially control the timing of major calving events by progressively damaging the glacier tongue.

River ice breakup and associated flooding are realities for many northern communities. This is certainly the case in Hay River, NWT, which is located at the junction of the Hay River and Great Slave Lake. Hay River experiences a wide range of spring river ice scenarios; from docile thermal melt outs, to severe ice jams resulting in life-threatening, disastrous flooding. This study involved the analysis of five seasons of aerial and time-lapse photographs, water level measurements and hydrometeorologic data. This work also compiled an extended historical record of breakup in the Hay River delta, which was compared against the field data gathered for this study; combining local, experiential knowledge with scientific observation into a cohesive description of breakup. This will be used to advise the non-technical flood watch community on the patterns of timing and sequencing of breakup, which is critical for evacuation planning. / Water Resources Engineering

Inhibiting the formation of ice is an essential process commercially, industrially, and medically. Compounds that work to stop the formation of ice have historically possessed drawbacks such as toxicity or prohibitively high active concentrations. One class of molecules, ice recrystallization inhibitors, work to reduce the damage caused by the combination of small ice crystals into larger ones. Recent advances made by the Ben lab have identified small molecule carbohydrate analogues that are highly active in the field of ice recrystallization and have potential in the cryopreservation of living tissue. A similar class of molecules, kinetic hydrate inhibitors, work to prevent the formation of another type of ice – gas hydrate. Gas hydrates are formed by the encapsulation of a molecule of a hydrocarbon inside a growing ice crystal. These compounds become problematic in high pressure and low temperature areas where methane is present - such as an oil pipeline. A recent study has highlighted the effects of antifreeze glycoprotein, a biological ice recrystallization inhibitor, in the inhibition of methane clathrates. Connecting these two fields through the synthesis and testing of small molecule ice recrystallization inhibitors in the inhibition of methane hydrates is unprecedented and may lead to a novel class of compounds.

Univ., Diss.--Trier, 2004.