Sidecut radius and kinetic energy: equipment designed to reduce risk of severe traumatic knee injuries in alpine giant slalom ski racing

PubMed Central

Kröll, Josef; Spörri, Jörg; Gilgien, Matthias; Schwameder, Hermann; Müller, Erich

2016-01-01

Background Kinetic energy (Ekin) increases with speed by the power of 2 and is considered a major risk factor for injuries in alpine ski racing. There is no empirical knowledge about the effect of ski geometry on Ekin. Consequently, the aim of this study was to investigate the influence of sidecut radius on the progress of Ekin while skiing through a multigate section in giant slalom (GS). Methods 5 European-Cup level athletes skied on three different pairs of GS skis varying in sidecut radii (30, 35 and 40 m). Each athlete's position over time within a six gate section (including flat and steep terrain) was captured by the use of a differential Global Navigational Satellite System. Ekin, speed, time and path length were analysed for each pair of skis used. Results When using skis with greater sidecut radius, average Ekin was significantly lower over the entire six gate section, but not locally at every turn cycle. Particular decreases of Ekin were observed for both turns on the flat terrain, as well as for the turn at the terrain transition and the first turn on the steep terrain. The observed decreases in Ekin were found to be primarily explainable by increases in turn time. Conclusions With respect to typical sport mechanisms that cause severe knee injuries, using skis with greater sidecut radius potentially provides additional injury preventative gain, particularly in specific areas within a run. However, this injury preventative gain during falls in GS should not be overestimated. PMID:26702015

Exploring the Potential of Aerial Photogrammetry for 3d Modelling of High-Alpine Environments

NASA Astrophysics Data System (ADS)

Legat, K.; Moe, K.; Poli, D.; Bollmannb, E.

2016-03-01

High-alpine areas are subject to rapid topographic changes, mainly caused by natural processes like glacial retreat and other geomorphological processes, and also due to anthropogenic interventions like construction of slopes and infrastructure in skiing resorts. Consequently, the demand for highly accurate digital terrain models (DTMs) in alpine environments has arisen. Public administrations often have dedicated resources for the regular monitoring of glaciers and natural hazard processes. In case of glaciers, traditional monitoring encompasses in-situ measurements of area and length and the estimation of volume and mass changes. Next to field measurements, data for such monitoring programs can be derived from DTMs and digital ortho photos (DOPs). Skiing resorts, on the other hand, require DTMs as input for planning and - more recently - for RTK-GNSS supported ski-slope grooming. Although different in scope, the demand of both user groups is similar: high-quality and up-to-date terrain data for extended areas often characterised by difficult accessibility and large elevation ranges. Over the last two decades, airborne laser scanning (ALS) has replaced photogrammetric approaches as state-of-the-art technology for the acquisition of high-resolution DTMs also in alpine environments. Reasons include the higher productivity compared to (manual) stereo-photogrammetric measurements, canopy-penetration capability, and limitations of photo measurements on sparsely textured surfaces like snow or ice. Nevertheless, the last few years have shown strong technological advances in the field of aerial camera technology, image processing and photogrammetric software which led to new possibilities for image-based DTM generation even in alpine terrain. At Vermessung AVT, an Austrian-based surveying company, and its subsidiary Terra Messflug, very promising results have been achieved for various projects in high-alpine environments, using images acquired by large-format digital cameras of Microsoft's UltraCam series and the in-house processing chain centred on the Dense-Image-Matching (DIM) software SURE by nFrames. This paper reports the work carried out at AVT for the surface- and terrain modelling of several high-alpine areas using DIM- and ALS-based approaches. A special focus is dedicated to the influence of terrain morphology, flight planning, GNSS/IMU measurements, and ground-control distribution in the georeferencing process on the data quality. Based on the very promising results, some general recommendations for aerial photogrammetry processing in high-alpine areas are made to achieve best possible accuracy of the final 3D-, 2.5D- and 2D products.

Sidecut radius and the mechanics of turning—equipment designed to reduce risk of severe traumatic knee injuries in alpine giant slalom ski racing

PubMed Central

Spörri, Jörg; Kröll, Josef; Gilgien, Matthias; Müller, Erich

2016-01-01

Background There is limited empirical knowledge about the effect of ski geometry, particularly in the context of injury prevention in alpine ski racing. We investigated the effect of sidecut radius on biomechanical variables related to the mechanics of turning. Methods During a field experiment, six European Cup level athletes skied on three different pairs of giant slalom (GS) skis varying in sidecut radii (30 m, 35 m and 40 m). Using a video-based three-dimensional (3D) kinematic system, a 22-point body segment model of the athletes was reconstructed in 3D, and the variables ground reaction force, centre of mass (COM) speed, COM turn radius, ski turn radius, edge angle, fore/aft position and skid angle were calculated. Results While steering out of the fall line after gate passage, ground reaction force significantly differed between the 30 m and 40 m skis and between the 35 m and 40 m skis. These differences were mainly explainable by larger COM turn radii when skiing on the 40 m ski. During the same turn phase, significant differences in ski turn radius also were found, but there were no differences in edge angle, fore/aft position and skid angle. Summary The sidecut-induced reduction in ground reaction force and the sidecut-induced increase in centre of mass and ski turn radius observed in this study provides indirect evidence of reduced self-steering of the ski. Self-steering plays a central role in the mechanism of anterior cruciate ligament rupture in alpine ski racing. PMID:26702014

Nutrient status in soil of Ski runs in the sub-alpine belt of Uludag Mountain, Bursa, Turkey.

PubMed

Guleryuz, Gurcan; Kirmizi, Serap; Arslan, Hulya

2010-01-01

Large areas of land are disturbed in sensitive bio-diverse mountain environments by Skiruns. Restoration of vegetation on such disturbed mountain sites may be hampered by soil degradation but the severity and nature of the constraints is not well understood. This study was designed to compare the water holding and nutritional status of soil in three Ski runs which had different construction dates and disturbance levels, and the adjacent undisturbed site in the Abies bommuelleriana forest community in the sub-alpine belt of Uludag Mountain (Bithynian Olympus). The values of soil parameters were depressed in proportion to the disturbance level. Water holding capacity (WHC), total nitrogen (N), organic carbon (C) and calcium (Ca2+), magnesium (Mg2+) and potassium (K+) contents (mg kg(-1) dry weight) of soils in the Ski run which had the highest disturbance level were lower than that of the undisturbed adjacent sites. However the results indicated that the soil parameters were less degraded when secondary vegetation was growing on the disturbed areas.

Alpine ski and snowboarding traumatic injuries: incidence, injury patterns, and risk factors for 10 years.

PubMed

McBeth, Paul B; Ball, Chad G; Mulloy, Robert H; Kirkpatrick, Andrew W

2009-05-01

Alpine skiing and snowboarding are popular winter sports in Canada. Every year participation in these activities results in traumatic injury. The purpose of this study was to identify the incidence and injury patterns, as well as risk factors associated with ski and snowboarding injuries. A comprehensive 10-year retrospective review of Alpine ski and snowboarding injuries from 1996 to 2006 was conducted. The Alberta Trauma Registry was used as the primary source of data. A total of 196 patients (56.6% skiers, 43.4% snowboarders) were identified as having major traumatic injuries (Injury Severity Score, >or=12). Forty-three patients required intensive care unit support. The majority of injuries were related to falls and collisions with natural objects. Head injuries were most common, followed by chest, spinal, and extremity trauma. Seventy-nine patients required emergency surgery. Skiing and snowboarding represent activities with high potential for traumatic injury. Safety initiatives should be developed to target this population.

75 FR 77826 - White River National Forest; Eagle County, CO; Beaver Creek Mountain Improvements

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-14

... and/or affected individuals, organizations and governmental agencies will be used to identify resource... upcoming 2015 World Alpine Championships. In order for Beaver Creek to continue to host international... located at Beaver Creek. Hosting the 2015 International Skiing Federation (FIS) World Alpine Ski...

Balance, Basic Anthropometrics and Performance in Young Alpine Skiers; Longitudinal Analysis of the Associations During two Competitive Seasons

PubMed Central

Lesnik, Blaz; Sekulic, Damir; Supej, Matej; Esco, Michael R; Zvan, Milan

2017-01-01

Abstract Balance is hypothesized to be important in alpine skiing, while it is known that balance depends on anthropometric indices. The aim of this investigation was to explore the association between balance, anthropometrics and skiing-results over two competitive seasons among youth alpine-skiers. Eighty-one skiers (40 females) participated in this study. The participants were tested twice over two competitive seasons: when they were 12-13 years old (U14) and when they were 14-15 years old (U16). The variables consisted of anthropometrics (body height and body mass) and three balance indexes (medio-lateral-, anterio-posterior- and overall-stability-index). Additionally, skiing results in U14 and U16 were evaluated. The balance status did not change significantly over the observed period of time regardless of the significant changes in body mass and height. The relationships between balance and skiing results were higher in the U14 (Pearson’s r = 0.45-0.54) than in the U16 (Pearson’s r = 0.05-0.28). The relationships between anthropometrics and competitive results were generally stronger in girls (Pearson’s r = 0.39-0.88) than in boys (Pearson’s r = 0.26-0.58). After clustering athletes into three achievement groups on a basis of their competitive performance, discriminant canonical analysis showed that relationships between balance and skiing results decreased, while the relationships between anthropometrics and skiing results increased over the two observed seasons. This study highlighted the importance of balance in youth alpine skiing in the age range of 11-14 years. PMID:28713454

Balance, Basic Anthropometrics and Performance in Young Alpine Skiers; Longitudinal Analysis of the Associations During two Competitive Seasons.

PubMed

Lesnik, Blaz; Sekulic, Damir; Supej, Matej; Esco, Michael R; Zvan, Milan

2017-06-01

Balance is hypothesized to be important in alpine skiing, while it is known that balance depends on anthropometric indices. The aim of this investigation was to explore the association between balance, anthropometrics and skiing-results over two competitive seasons among youth alpine-skiers. Eighty-one skiers (40 females) participated in this study. The participants were tested twice over two competitive seasons: when they were 12-13 years old (U14) and when they were 14-15 years old (U16). The variables consisted of anthropometrics (body height and body mass) and three balance indexes (medio-lateral-, anterio-posterior- and overall-stability-index). Additionally, skiing results in U14 and U16 were evaluated. The balance status did not change significantly over the observed period of time regardless of the significant changes in body mass and height. The relationships between balance and skiing results were higher in the U14 (Pearson's r = 0.45-0.54) than in the U16 (Pearson's r = 0.05-0.28). The relationships between anthropometrics and competitive results were generally stronger in girls (Pearson's r = 0.39-0.88) than in boys (Pearson's r = 0.26-0.58). After clustering athletes into three achievement groups on a basis of their competitive performance, discriminant canonical analysis showed that relationships between balance and skiing results decreased, while the relationships between anthropometrics and skiing results increased over the two observed seasons. This study highlighted the importance of balance in youth alpine skiing in the age range of 11-14 years.

Physiological Responses of Elderly Recreational Alpine Skiers of Different Fitness and Skiing Abilities

PubMed Central

Krautgasser, Sabine; Scheiber, Peter; von Duvillard, Serge P.; Müller, Erich

2011-01-01

We measured physiological responses of elderly recreational skiers of different fitness and skiing abilities. Six subjects (mean age: 61.2 ± 4.6 yrs; Wt: 76.8 ± 15.6 kg; Ht: 1.69 ± 0.10 m; BMI: 26.9 ± 5.0) were tested in a laboratory and during 30 and 75 min of recreational downhill skiing. Oxygen uptake (VO2), heart rate (HR), blood lactate (LA) concentration, and diastolic (DBP) and systolic (SBP) blood pressure were used to estimate energy demands while skiing. During maximal testing in a laboratory, subjects achieved a mean maximal VO2max of 28.2 ± 7.5 ml.kg-1.min-1 and a mean HRpeak of 165 ± 4 bpm (98 ± 1% of HRmax). Mean maximal workload measured on a cycle ergometer was 2.2 ± 0.7 W.kg-1 with a mean LApeak of 7.4 ± 1 mmol.l-1. During field testing, mean VO2 during skiing was 12 ± 2 ml.kg-1.min-1 (45 ± 16% of VO2max). Skiing VO2peak was 19 ± 5 ml. kg-1.min-1 (72 ± 23% of VO2max) was lower than VO2max in the lab (p = 0.04). Mean HR during skiing was 126 ± 2 bpm (77 ± 1% of HRmax from lab tests). Skiing HRpeak was 162 ± 2 bpm. This was not different from HRmax in the lab (p = 0.68). Mean LA after 30 and 75 min of skiing was not different (2.2 ± 0.8 mmol.l-1 and 2.0 ± 0.8, respectively, p = 0.71). Both LA samples during skiing were lower than lab tests (p < 0.0001). There was no difference for DBP between field and laboratory tests; however, SBP increased after 30 min of skiing to 171 ± 20 (p < 0.009) and 165 ± 17 (p < 0.003) after 75 min. These remained below the mean peak SBP determined in lab tests (218+31). Mean oxygen demand during 30 and 75 min of recreational skiing is only 45% of VO2max while mean HR is 77% of HRmax. This departure from linearity not often seen in typical aerobic activities suggests that alpine skiing requires a combination of aerobic and anaerobic activity. Blood LA remained low during skiing suggesting that elderly skiers may govern their intensity via signals closer to VO2 and LA compared to HR or BP. Key points Recreational Alpine skiing for elderly population does not pose health risks Blood pressure and heart rate during recreational Alpine skiing is retain within normal limits Blood lactate levels remain relatively low and do not contribute to fatigue Oxygen uptake and blood lactate are better markers of intensity in elderly Alpine skier compared to heart rate and blood pressure. PMID:24149569

Risk Factors for Anterior Cruciate Ligament Injury in Competitive Adolescent Alpine Skiers

PubMed Central

Westin, Maria; Harringe, Marita L.; Engström, Björn; Alricsson, Marie; Werner, Suzanne

2018-01-01

Background: There is a high risk for anterior cruciate ligament (ACL) injuries in alpine skiers. To reduce or try to prevent these injuries, intrinsic and extrinsic risk factors need to be identified. Purpose: To identify possible intrinsic and extrinsic ACL injury risk factors among competitive adolescent alpine skiers. Study Design: Case-control study; Level of evidence, 3. Methods: Between 2006 and 2009, a cohort of 339 alpine ski students (176 male, 163 female) from Swedish ski high schools were prospectively observed in terms of ACL injuries. First-time ACL injuries were recorded. In September, prior to each ski season, the skiers were clinically examined according to a specific knee protocol. Results: Overall, 11 male and 14 female skiers sustained a total of 25 first-episode ACL injuries. The majority of injuries occurred in the left knee (P < .05). Skiers who had participated in alpine skiing for >13 years (hazard ratio, 0.83; 95% CI, 0.68-1.00; P < .05) had a reduced risk of sustaining an ACL injury. Eighteen ACL injuries occurred during training, 12 in the technical discipline of giant slalom, and 8 in slalom. Fourteen skiers reported not to be fatigued at all at the time of injury, and 8 skiers reported that they were somewhat fatigued. Conclusion: ACL injuries occurred more often in the left knee than the right. This should be taken into consideration in the design of ACL injury prevention programs. Those who reported a higher number of active years in alpine skiing showed a reduced risk of sustaining an ACL injury. No other factor among those studied could be identified as an independent risk factor for ACL injury. PMID:29780835

Whole-Body Vibrations Associated With Alpine Skiing: A Risk Factor for Low Back Pain?

PubMed Central

Supej, Matej; Ogrin, Jan; Holmberg, Hans-Christer

2018-01-01

Alpine skiing, both recreational and competitive, is associated with high rates of injury. Numerous studies have shown that occupational exposure to whole-body vibrations is strongly related to lower back pain and some suggest that, in particular, vibrations of lower frequencies could lead to overuse injuries of the back in connection with alpine ski racing. However, it is not yet known which forms of skiing involve stronger vibrations and whether these exceed safety thresholds set by existing standards and directives. Therefore, this study was designed to examine whole-body vibrations connected with different types of skiing and the associated potential risk of developing low back pain. Eight highly skilled ski instructors, all former competitive ski racers and equipped with five accelerometers and a Global Satellite Navigation System to measure vibrations and speed, respectively, performed six different forms of skiing: straight running, plowing, snow-plow swinging, basic swinging, short swinging, and carved turns. To estimate exposure to periodic, random and transient vibrations the power spectrum density (PSD) and standard ISO 2631-1:1997 parameters [i.e., the weighted root-mean-square acceleration (RMS), crest factor, maximum transient vibration value and the fourth-power vibration dose value (VDV)] were calculated. Ground reaction forces were estimated from data provided by accelerometers attached to the pelvis. The major novel findings were that all of the forms of skiing tested produced whole-body vibrations, with highest PSD values of 1.5–8 Hz. Intensified PSD between 8.5 and 35 Hz was observed only when skidding was involved. The RMS values for 10 min of short swinging or carved turns, as well as all 10-min equivalent VDV values exceeded the limits set by European Directive 2002/44/EC for health and safety. Thus, whole-body vibrations, particularly in connection with high ground reaction forces, contribute to a high risk for low back pain among active alpine skiers. PMID:29593563

The Relationship among Leg Strength, Leg Power and Alpine Skiing Success.

ERIC Educational Resources Information Center

Gettman, Larry R.; Huckel, Jack R.

The purpose of this study was to relate leg strength and power to alpine skiing success as measured by FIS points. Isometric leg strength was represented by the knee extension test described by Clarke. Leg power was measured by the vertical jump test and the Margaria-Kalamen stair run. Results in the strength and power tests were correlated with…

A sit-ski design aimed at controlling centre of mass and inertia.

PubMed

Langelier, Eve; Martel, Stéphane; Millot, Anne; Lessard, Jean-Luc; Smeesters, Cécile; Rancourt, Denis

2013-01-01

This article introduces a sit-ski developed for the Canadian Alpine Ski Team in view of the Vancouver 2010 Paralympic games. The design is predominantly based on controlling the mass distribution of the sit-ski, a critical factor in skiing performance and control. Both the antero-posterior location of the centre of mass and the sit-ski moment of inertia were addressed in our design. Our design provides means to adjust the antero-posterior centre of mass location of a sit-ski to compensate for masses that would tend to move the antero-posterior centre of mass location away from the midline of the binding area along the ski axis. The adjustment range provided is as large as 140 mm, thereby providing sufficient adaptability for most situations. The suspension mechanism selected is a four-bar linkage optimised to limit antero-posterior seat movement, due to suspension compression, to 7 mm maximum. This is about 5% of the maximum antero-posterior centre of mass control capacity (151 mm) of a human participant. Foot rest inclination was included in the design to modify the sit-ski inertia by as much as 11%. Together, these mass adjustment features were shown to drastically help athletes' skiing performance.

Analysis of a severe head injury in World Cup alpine skiing.

PubMed

Yamazaki, Junya; Gilgien, Matthias; Kleiven, Svein; McIntosh, Andrew S; Nachbauer, Werner; Müller, Erich; Bere, Tone; Bahr, Roald; Krosshaug, Tron

2015-06-01

Traumatic brain injury (TBI) is the leading cause of death in alpine skiing. It has been found that helmet use can reduce the incidence of head injuries between 15% and 60%. However, knowledge on optimal helmet performance criteria in World Cup alpine skiing is currently limited owing to the lack of biomechanical data from real crash situations. This study aimed to estimate impact velocities in a severe TBI case in World Cup alpine skiing. Video sequences from a TBI case in World Cup alpine skiing were analyzed using a model-based image matching technique. Video sequences from four camera views were obtained in full high-definition (1080p) format. A three-dimensional model of the course was built based on accurate measurements of piste landmarks and matched to the background video footage using the animation software Poser 4. A trunk-neck-head model was used for tracking the skier's trajectory. Immediately before head impact, the downward velocity component was estimated to be 8 m·s⁻¹. After impact, the upward velocity was 3 m·s⁻¹, whereas the velocity parallel to the slope surface was reduced from 33 m·s⁻¹ to 22 m·s⁻¹. The frontal plane angular velocity of the head changed from 80 rad·s⁻¹ left tilt immediately before impact to 20 rad·s⁻¹ right tilt immediately after impact. A unique combination of high-definition video footage and accurate measurements of landmarks in the slope made possible a high-quality analysis of head impact velocity in a severe TBI case. The estimates can provide crucial information on how to prevent TBI through helmet performance criteria and design.

The Waist Width of Skis Influences the Kinematics of the Knee Joint in Alpine Skiing

PubMed Central

Zorko, Martin; Nemec, Bojan; Babič, Jan; Lešnik, Blaz; Supej, Matej

2015-01-01

Recently alpine skis with a wider waist width, which medially shifts the contact between the ski edge and the snow while turning, have appeared on the market. The aim of this study was to determine the knee joint kinematics during turning while using skis of different waist widths (65mm, 88mm, 110mm). Six highly skilled skiers performed ten turns on a predefined course (similar to a giant slalom course). The relation of femur and tibia in the sagital, frontal and coronal planes was captured by using an inertial motion capture suit, and Global Navigation Satellite System was used to determine the skiers’ trajectories. With respect of the outer ski the knee joint flexion, internal rotation and abduction significantly decreased with the increase of the ski waist width for the greatest part of the ski turn. The greatest abduction with the narrow ski and the greatest external rotation (lowest internal rotation) with the wide ski are probably the reflection of two different strategies of coping the biomechanical requirements in the ski turn. These changes in knee kinematics were most probably due to an active adaptation of the skier to the changed biomechanical conditions using wider skis. The results indicated that using skis with large waist widths on hard, frozen surfaces could bring the knee joint unfavorably closer to the end of the range of motion in transversal and frontal planes as well as potentially increasing the risk of degenerative knee injuries. Key points The change in the skis’ waist width caused a change in the knee joint movement strategies, which had a tendency to adapt the skier to different biomechanical conditions. The use of wider skis or, in particular, skis with a large waist width, on a hard or frozen surface, could unfavourably bring the knee joint closer to the end of range of motion in transversal and frontal planes as well as may potentially increase the risk of degenerative knee injuries. The overall results of the abduction and internal rotation in respect to turn radii and ground reaction forces indicated that the knee joint movements are likely one of the key points in alpine skiing techniques. However, the skiing equipment used can still significantly influence the movement strategy. PMID:26336348

Alpine Skiing With total knee ArthroPlasty (ASWAP): metabolism, inflammation, and skeletal muscle fiber characteristics.

PubMed

Kristensen, M; Pötzelsberger, B; Scheiber, P; Bergdahl, A; Hansen, C N; Andersen, J L; Narici, M; Salvioli, S; Conte, M; Müller, E; Dela, F

2015-08-01

We investigated the effect of alpine skiing for 12 weeks on skeletal muscle characteristics and biomarkers of glucose homeostasis and cardiovascular risk factors. Twenty-three patients with a total knee arthroplasty (TKA) were studied 2.9 ± 0.9 years (mean ± SD) after the operation. Fourteen patients participated in the intervention group (IG) and nine in the control group (CG). Blood samples and muscle biopsies were obtained before (PRE) and 7.3 ± 0.8 days after (POST) the intervention, and blood samples again after a retention (RET) phase of 8 weeks. With skiing, glucose homeostasis improved in IG (decrease in fasting insulin, increase in muscle glycogen) but not in CG. Fiber type distribution and size, as well as capillary density and number of capillaries around the fibers (CAF), were not different between the operated and the non-operated leg in either group. The relative number of type I fibers increased with skiing in IG with no change in CG. Inflammatory biomarkers, plasma lipids, and mitochondrial proteins and activity did not change. Alpine skiing is metabolically beneficial and can be used as a training modality by elderly people with TKA. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Hydrology and water quality in two mountain basins of the northeastern US: Assessing baseline conditions and effects of ski area development

USGS Publications Warehouse

Wemple, B.; Shanley, J.; Denner, J.; Ross, D.; Mills, K.

2007-01-01

Mountain regions throughout the world face intense development pressures associated with recreational and tourism uses. Despite these pressures, much of the research on bio-geophysical impacts of humans in mountain regions has focused on the effects of natural resource extraction. This paper describes findings from the first 3 years of a study examining high elevation watershed processes in a region undergoing alpine resort development. Our study is designed as a paired-watershed experiment. The Ranch Brook watershed (9.6 km2) is a relatively pristine, forested watershed and serves as the undeveloped 'control' basin. West Branch (11.7 km2) encompasses an existing alpine ski resort, with approximately 17% of the basin occupied by ski trails and impervious surfaces, and an additional 7% slated for clearing and development. Here, we report results for water years 2001-2003 of streamflow and water quality dynamics for these watersheds. Precipitation increases significantly with elevation in the watersheds, and winter precipitation represents 36-46% of annual precipitation. Artificial snowmaking from water within West Branch watershed currently augments annual precipitation by only 3-4%. Water yield in the developed basin exceeded that in the control by 18-36%. Suspended sediment yield was more than two and a half times greater and fluxes of all major solutes were higher in the developed basin. Our study is the first to document the effects of existing ski area development on hydrology and water quality in the northeastern US and will serve as an important baseline for evaluating the effects of planned resort expansion activities in this area.

High Performance Skiing. How to Become a Better Alpine Skier.

ERIC Educational Resources Information Center

Yacenda, John

This book is intended for people who desire to improve their skiing by exploring high performance techniques leading to: (1) more consistent performance; (2) less fatigue and more endurance; (3) greater strength and flexibility; (4) greater versatility; (5) greater confidence in all skiing conditions; and (6) the knowledge to participate in…

Estimation of Alpine Skier Posture Using Machine Learning Techniques

PubMed Central

Nemec, Bojan; Petrič, Tadej; Babič, Jan; Supej, Matej

2014-01-01

High precision Global Navigation Satellite System (GNSS) measurements are becoming more and more popular in alpine skiing due to the relatively undemanding setup and excellent performance. However, GNSS provides only single-point measurements that are defined with the antenna placed typically behind the skier's neck. A key issue is how to estimate other more relevant parameters of the skier's body, like the center of mass (COM) and ski trajectories. Previously, these parameters were estimated by modeling the skier's body with an inverted-pendulum model that oversimplified the skier's body. In this study, we propose two machine learning methods that overcome this shortcoming and estimate COM and skis trajectories based on a more faithful approximation of the skier's body with nine degrees-of-freedom. The first method utilizes a well-established approach of artificial neural networks, while the second method is based on a state-of-the-art statistical generalization method. Both methods were evaluated using the reference measurements obtained on a typical giant slalom course and compared with the inverted-pendulum method. Our results outperform the results of commonly used inverted-pendulum methods and demonstrate the applicability of machine learning techniques in biomechanical measurements of alpine skiing. PMID:25313492

Long-Term Athletic Development in Youth Alpine Ski Racing: The Effect of Physical Fitness, Ski Racing Technique, Anthropometrics and Biological Maturity Status on Injuries

PubMed Central

Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian

2017-01-01

Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9–14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T-tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p < 0.05. Relatively low rates of injuries were reported for both traumatic (0.63 TI/athlete) and overuse injuries (0.21 OI/athlete). Athletes with higher body weight, body height, and sitting height; lower APHV values; better core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness parameters is crucial to help to prevent injury in youth ski racing. The present findings suggest that neuromuscular training should be incorporated into the training regimen of youth ski racers to prevent injuries. PMID:28912731

Long-Term Athletic Development in Youth Alpine Ski Racing: The Effect of Physical Fitness, Ski Racing Technique, Anthropometrics and Biological Maturity Status on Injuries.

PubMed

Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian

2017-01-01

Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9-14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T -tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p < 0.05. Relatively low rates of injuries were reported for both traumatic (0.63 TI/athlete) and overuse injuries (0.21 OI/athlete). Athletes with higher body weight, body height, and sitting height; lower APHV values; better core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness parameters is crucial to help to prevent injury in youth ski racing. The present findings suggest that neuromuscular training should be incorporated into the training regimen of youth ski racers to prevent injuries.

Determination of the centre of mass kinematics in alpine skiing using differential global navigation satellite systems.

PubMed

Gilgien, Matthias; Spörri, Jörg; Chardonnens, Julien; Kröll, Josef; Limpach, Philippe; Müller, Erich

2015-01-01

In the sport of alpine skiing, knowledge about the centre of mass (CoM) kinematics (i.e. position, velocity and acceleration) is essential to better understand both performance and injury. This study proposes a global navigation satellite system (GNSS)-based method to measure CoM kinematics without restriction of capture volume and with reasonable set-up and processing requirements. It combines the GNSS antenna position, terrain data and the accelerations acting on the skier in order to approximate the CoM location, velocity and acceleration. The validity of the method was assessed against a reference system (video-based 3D kinematics) over 12 turn cycles on a giant slalom skiing course. The mean (± s) position, velocity and acceleration differences between the CoM obtained from the GNSS and the reference system were 9 ± 12 cm, 0.08 ± 0.19 m · s(-1) and 0.22 ± 1.28 m · s(-2), respectively. The velocity and acceleration differences obtained were smaller than typical differences between the measures of several skiers on the same course observed in the literature, while the position differences were slightly larger than its discriminative meaningful change. The proposed method can therefore be interpreted to be technically valid and adequate for a variety of biomechanical research questions in the field of alpine skiing with certain limitations regarding position.

Technical snow production in skiing areas: conditions, practice, monitoring and modelling. A case study in Mayrhofen/Austria

NASA Astrophysics Data System (ADS)

Strasser, Ulrich; Hanzer, Florian; Marke, Thomas; Rothleitner, Michael

2017-04-01

The production of technical snow today is a self-evident feature of modern alpine skiing resort management. Millions of Euros are invested every year for the technical infrastructure and its operation to produce a homogeneous and continuing snow cover on the skiing slopes for the winter season in almost every larger destination in the Alps. In Austria, skiing tourism is a significant factor of the national economic structure. We present the framing conditions of technical snow production in the mid-size skiing resort of Mayrhofen (Zillertal Alps/Austria, 136 km slopes, elevation range 630 - 2.500 m a.s.l.). Production conditions are defined by the availability of water, the planned date for the season opening, and the climatic conditions in the weeks before. By means of an adapted snow production strategy an attempt is made to ecologically and economically optimize the use of water and energy resources. Monitoring of the snow cover is supported by a network of low-cost sensors and mobile snow depth recordings. Finally, technical snow production is simulated with the spatially distributed, physically based hydroclimatological model AMUNDSEN. The model explicitly considers individual snow guns and distributes the produced snow along the slopes. The amount of simulated snow produced by each device is a function of its type, of actual wet-bulb temperature at the location, of ski area infrastructure (in terms of water supply and pumping capacity), and of snow demand.

Maturity status influences the relative age effect in national top level youth alpine ski racing and soccer

PubMed Central

Müller, Lisa; Gonaus, Christoph; Perner, Christoph; Müller, Erich; Raschner, Christian

2017-01-01

Since the relative age effect (RAE) characterizes a problem in all age categories of alpine ski racing and soccer and the fact that, yet, to date the underlying factors have not been well investigated, the aim of the present study was to assess the influence of the biological maturity status on the RAE among youth alpine ski racers (YSR) and soccer players (SP). In total, 183 male and female YSR selected for national final races and 423 male SP selected for Elite Youth Development Centres were investigated. Additionally, a comparison group of 413 non-athletes was evaluated. The birth months were split into four relative age quarters. The biological maturity status was assessed by the age at peak height velocity (APHV) method; according to the M±SD of the comparison group, the athletes were divided into normal, early and late maturing. Chi2-tests indicated a significant RAE among YSR (χ2(3,N = 183) = 18.0; p<0.001; ω = 0.31) and SP (χ2(3,N = 423) = 33.1; p<0.001; ω = 0.28). In total, only a small number of late maturing athletes were present (0.5–2.3%). Among relatively younger athletes, high percentages of early maturing athletes were found (43.1–43.3%). The findings indicate that relatively younger and less mature athletes are marginalized or totally excluded in alpine ski racing and soccer. Thus, selection criteria in both sports are effectively based on early biological development and relatively older age, both of which should be considered in future in the talent selection process. In this context, the easy feasible method of assessing the APHV can be used. PMID:28759890

Spatially explicit modeling of conflict zones between wildlife and snow sports: prioritizing areas for winter refuges.

PubMed

Braunisch, Veronika; Patthey, Patrick; Arlettaz, Raphaël

2011-04-01

Outdoor winter recreation exerts an increasing pressure upon mountain ecosystems, with unpredictable, free-ranging activities (e.g., ski mountaineering, snowboarding, and snowshoeing) representing a major source of stress for wildlife. Mitigating anthropogenic disturbance requires the spatially explicit prediction of the interference between the activities of humans and wildlife. We applied spatial modeling to localize conflict zones between wintering Black Grouse (Tetrao tetrix), a declining species of Alpine timberline ecosystems, and two free-ranging winter sports (off-piste skiing [including snow-boarding] and snowshoeing). Track data (snow-sports and birds' traces) obtained from aerial photographs taken over a 585-km transect running along the timberline, implemented within a maximum entropy model, were used to predict the occurrence of snow sports and Black Grouse as a function of landscape characteristics. By modeling Black Grouse presence in the theoretical absence of free-ranging activities and ski infrastructure, we first estimated the amount of habitat reduction caused by these two factors. The models were then extrapolated to the altitudinal range occupied by Black Grouse, while the spatial extent and intensity of potential conflict were assessed by calculating the probability of human-wildlife co-occurrence. The two snow-sports showed different distribution patterns. Skiers' occurrence was mainly determined by ski-lift presence and a smooth terrain, while snowshoers' occurrence was linked to hiking or skiing routes and moderate slopes. Wintering Black Grouse avoided ski lifts and areas frequented by free-ranging snow sports. According to the models, Black Grouse have faced a substantial reduction of suitable wintering habitat along the timberline transect: 12% due to ski infrastructure and another 16% when adding free-ranging activities. Extrapolating the models over the whole study area results in an overall habitat loss due to ski infrastructure of 10%, while there was a > 10% probability of human-wildlife encounters on 67% of the remaining area of suitable wintering habitat. Only 23% of the wintering habitat was thus free of anthropogenic disturbance. By identifying zones of potential conflict, while rating its relative intensity, our model provides a powerful tool to delineate and prioritize areas where wildlife winter refuges and visitor steering measures should be implemented.

A systematic video analysis of 69 injury cases in World Cup alpine skiing.

PubMed

Bere, T; Flørenes, T W; Krosshaug, T; Haugen, P; Svandal, I; Nordsletten, L; Bahr, R

2014-08-01

We have limited insight into how injuries occur in professional ski racing. The aim of this study was to describe the injury situations in World Cup alpine skiing. Injuries reported through the International Ski Federation Injury Surveillance System for three consecutive World Cup seasons (2006-2009) were obtained on video. In total, 69 injuries and 124 runs of matched controls were analysed by five experts to evaluate the skiing situation, skier behavior, as well as piste-related factors. A chi-square test (95% CI, P ≤ 0.05) was used to examine whether there was a difference between course sections regarding where the injury situation occurred. The skier was most frequently turning (n = 55) or landing from a jump (n = 13) at the time of injury. Most of the injuries to the head and upper body (96%) resulted from crashes, while the majority of knee injuries (83%) occurred while the skier was still skiing. Gate contact contributed to 30% of the injuries, while 9% occurred at contact with safety nets/material. Almost half of the injuries (46%) occurred in the final fourth of the course. A particular concern was the high contribution of inappropriate gate contact and the high-energy impacts to the body when crashing. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Epidemiology of winter sport injuries].

PubMed

Heim, D; Weymann, A; Loeliger, U; Matter, P

1993-01-01

The region Davos/Klosters is a big wintersport area in Switzerland, where more than 5 million kilometers of vertical drop are skied per year. Over the last 20 years 28,777 patients with wintersport accidents have been treated in the 100-bed hospital of Davos, 85% of these patients have sustained their accident while skiing. An analysis of these datas show an increase of ski accidents as well as an increase of the distance skied. Especially an increase in snowboard accidents is noted over the last few years with a preponderance of lesions of the upper extremity. Injuries of the head, the trunk and simple skin lacerations remain stable over that period. Injuries of the upper extremity are increasing, whereas lower extremity lesions are slightly decreasing. There is a significant decrease of fractures of the leg, while at the same time an important increase of knee injuries is noted. Young patients below 20 years and those between 31 and 40 years of age sustained less accidents over the last 20 years, while the rest of the alpine skiers remain more or less stable in their accident incidence.

Home advantage in the Winter Olympics (1908-1998).

PubMed

Balmer, N J; Nevill, A M; Williams, A M

2001-02-01

We obtained indices of home advantage, based on the medals won by competing nations, for each event held at the Winter Olympics from 1908 to 1998. These indices were designed to assess home advantage while controlling for nation strength, changes in the number of medals on offer and the performance of 'non-hosting' nations. Some evidence of home advantage was found in figure skating, freestyle skiing, ski jumping, alpine skiing and short track speed skating. In contrast, little or no home advantage was observed in ice hockey, Nordic combined, Nordic skiing, bobsled, luge, biathlon or speed skating. When all events were combined, a significant home advantage was observed (P = 0.029), although no significant differences in the extent of home advantage were found between events (P > 0.05). When events were grouped according to whether they were subjectively assessed by judges, significantly greater home advantage was observed in the subjectively assessed events (P = 0.037). This was a reflection of better home performances, suggesting that judges were scoring home competitors disproportionately higher than away competitors. Familiarity with local conditions was shown to have some effect, particularly in alpine skiing, although the bobsled and luge showed little or no advantage over other events. Regression analysis showed that the number of time zones and direction of travel produced no discernible trends or differences in performance.

What are the exercise-based injury prevention recommendations for recreational alpine skiing and snowboarding? A systematic review.

PubMed

Hébert-Losier, Kim; Holmberg, Hans-Christer

2013-05-01

Skiing and snowboarding are two activities that significantly contribute to the total number of sports-related injuries reported per year. Strength, endurance and cardiovascular fitness are central components in sports injury prevention. Providing exercises and training recommendations specific to recreational skiers and snowboarders is important in both injury prevention and reducing the prevalence and cost associated with alpine winter sports injuries. The aim of this paper was to systematically review the literature for injury prevention recommendations specific to recreational alpine skiers and snowboarders. The focus was to discern recommendations that targeted physical fitness, exercise and/or training in the prevention of musculoskeletal injuries in these two sports. Fourteen electronic databases were searched in October 2011 using relevant MeSH terms and key words. Articles were included if they addressed injury prevention, recreational alpine skiing or snowboarding and musculoskeletal injuries. Only original research articles published in peer-reviewed journals, and in the English-language, were reviewed. Articles on elite athletes were excluded. Two independent reviewers quality assessed articles meeting inclusion criteria using a modified version of the Downs and Black Quality Assessment Checklist. Data on study population, study design, study location and injury prevention recommendation(s) were extracted from articles using a standard form and subsequently categorized to facilitate data synthesis. A total of 30 articles met the inclusion criteria and were reviewed, having an average ± standard deviation quality score of 72% ± 17% (range: 23-100 %). Overall, 80 recommendations for the prevention of musculoskeletal injuries in recreational alpine skiers and snowboarders were identified and classified into five main groups: equipment (n = 24), education and knowledge (n = 11), awareness and behaviour (n = 15), experience (n = 10) and third-party involvement (n = 20). No recommendations pertained to physical fitness, exercise and/or training per se, or its role in preventing injury. A comprehensive meta-analysis was not possible because several articles did not report data in sufficient detail. The importance of targeting physical fitness in injury prevention is accepted in sports medicine and rehabilitation; yet, there was a paucity of articles included in this review that explicitly investigated this aspect with regards to recreational alpine skiing and snowboarding. The most frequent recommendations for preventing skiing and snowboarding injuries concerned equipment or the involvement of third parties. The dominance of equipment-related measures in the injury prevention literature may be rationalized from a sports biomechanics viewpoint, as these activities involve high velocities and impact forces. Nonetheless, this also indicates a need for appropriate levels of strength, endurance and conditioning to meet the technical demands of these sports. Bearing this in mind, future research is encouraged to investigate the role of physical fitness, exercise and training in decreasing the incidence and severity of skiing and snowboarding injuries in recreational athletes.

Using crowd-sourced photos to assess seasonal patterns of visitor use in mountain-protected areas.

PubMed

Walden-Schreiner, Chelsey; Rossi, Sebastian Dario; Barros, Agustina; Pickering, Catherine; Leung, Yu-Fai

2018-02-12

Managing protected areas effectively requires information about patterns of visitor use, but these data are often limited. We explore how geotagged photos on Flickr, a popular photo-sharing social-media site, can generate hotspot maps and distribution models of temporal and spatial patterns of use in two mountain-protected areas of high conservation value. In Aconcagua Provincial Park (Argentina), two routes to the summit of Aconcagua were used in summer, but most visitors stayed close to the main road, using formal and informal walking trails and the Visitor Centre, while in winter, there was very limited visitation. In Kosciuszko National Park (Australia), alpine walking trails were popular in summer, but in winter, most visitors stayed in the lower altitude ski resorts and ski trails. Results demonstrate the usefulness of social-media data alone as well as a complement for visitor monitoring, providing spatial and temporal information for site-specific and park-level management of visitors and potential impacts in conservation areas.

Life-style characteristics and cardiovascular risk factors in regular downhill skiers: an observational study

PubMed Central

2013-01-01

Background Downhill skiing is part of active life style in many residents of Alpine regions. However, only very little information is available whether downhill skiing on a regular basis is associated with a healthier life style resulting in the reduction of major risk factors for cardiovascular diseases and memory deficits when compared to the general population. Thus, the aim of the study was to compare life-style characteristics and cardiovascular risk factors between regular downhill skiers and the general population. Methods Self-reported health and life-style data were collected by questionnaire from 1259 long-term downhill skiers (971 males, aged 57.3 ± 14.6 years; 288 females, aged 47.7 ± 16.4 years) and compared with data from the general population. Results Long-term skiers showed more favourable life-style characteristics and a better health status than the general population. Prevalences of hypercholesterolemia, systemic hypertension, diabetes, the frequency of mental stress and the occurrence of memory deficits declined with increasing yearly skiing frequency. Conclusion Long-term alpine skiing on a regular basis may contribute to healthy aging by its association with a healthier life style. PMID:23987102

Changes in Quadriceps Muscle Activity During Sustained Recreational Alpine Skiing

PubMed Central

Kröll, Josef; Müller, Erich; Seifert, John G.; Wakeling, James M.

2011-01-01

During a day of skiing thousands of repeated contractions take place. Previous research on prolonged recreational alpine skiing show that physiological changes occur and hence some level of fatigue is inevitable. In the present paper the effect of prolonged skiing on the recruitment and coordination of the muscle activity was investigated. Six subjects performed 24 standardized runs. Muscle activity during the first two (PREskiing) and the last two (POSTskiing) runs was measured from the vastus lateralis (VL) and rectus femoris (RF) using EMG and quantified using wavelet and principal component analysis. The frequency content of the EMG signal shifted in seven out of eight cases significantly towards lower frequencies with highest effects observed for RF on outside leg. A significant pronounced outside leg loading occurred during POSTskiing and the timing of muscle activity peaks occurred more towards turn completion. Specific EMG frequency changes were observed at certain time points throughout the time windows and not over the whole double turn. It is suggested that general muscular fatigue, where additional specific muscle fibers have to be recruited due to the reduced power output of other fibers did not occur. The EMG frequency decrease and intensity changes for RF and VL are caused by altered timing (coordination) within the turn towards a most likely more uncontrolled skiing technique. Hence, these data provide evidence to suggest recreational skiers alter their skiing technique before a potential change in muscle fiber recruitment occurs. Key points The frequency content of the EMG signal shifted in seven out of eight cases significantly towards lower frequencies with highest effects observed for RF. General muscular fatigue, where additional specific fibers have to be recruited due to the reduced power output of other fibers, did not occur. A modified skiing style towards a less functional and hence more uncontrolled skiing technique seems to be a key issue with respect to the influence on muscle recruitment for applied prolonged skiing session. PMID:24149299

Expert - Non-expert differences in visual behaviour during alpine slalom skiing.

PubMed

Decroix, Marjolein; Wazir, Mohd Rozilee Wazir Norjali; Zeuwts, Linus; Deconinck, Frederik F J A; Lenoir, Matthieu; Vansteenkiste, Pieter

2017-10-01

The aim of this study was to investigate visual behaviour of expert and non-expert ski athletes during an alpine slalom. Fourteen non-experts and five expert slalom skiers completed an alpine slalom course in an indoor ski slope while wearing a head-mounted eye tracking device. Experts completed the slalom clearly faster than non-experts, but no significant difference was found in timing and position of the turn initiation. Although both groups already looked at future obstacles approximately 0,5s before passing the upcoming pole, the higher speed of experts implied that they shifted gaze spatially earlier in the bend than non-experts. Furthermore, experts focussed more on the second next pole while non-expert slalom skiers looked more to the snow surface immediately in front of their body. No difference was found in the fixation frequency, average fixation duration, and quiet eye duration between both groups. These results suggest that experts focus on the timing of their actions while non-experts still need to pay attention to the execution of these actions. These results also might suggest that ski trainers should instruct non-experts and experts to focus on the next pole and, shift their gaze to the second next pole shortly before reaching it. Based on the current study it seems unadvisable to instruct slalom skiers to look several poles ahead during the actual slalom. However, future research should test if these results still hold on a real outdoor slope, including multiple vertical gates. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of mountain resort development - a case study in Vermont USA

NASA Astrophysics Data System (ADS)

Shanley, J.; Wemple, B.

2012-04-01

The mountainous landscape of northern New England, USA, faces intense development pressure from recreational and tourism use. In 2000 we began a paired-watershed study in northern Vermont to examine the effects of alpine resort development on stream flow and water quality. To our knowledge this is the only gaged watershed study at a mountain resort. The adjacent paired watersheds have similar topography, relief, geology and forest type, and differ primarily in land use. Ranch Brook watershed (9.6 km2) is the undeveloped, nearly 100% forested control basin. West Branch watershed (11.7 km2) is the developed basin, encompassing a pre-existing alpine ski resort and state highway, with approximately 17% of the basin occupied by ski trails and impervious surfaces. Measurements during 2000-2003 showed suspended sediment yield was >2.5 times greater and concentrations of nitrate and chloride were significantly elevated at West Branch. From 2004 through 2007 the resort expanded with more ski trails, roads, parking areas, and vacation home development and now has 24% cleared land, with storm sewers draining lower developed areas of the alpine watershed. For the 11-year period of study, water yield in the developed basin exceeded that in the control by an average of nearly 21%. The higher runoff at West Branch occurred primarily as result of higher sustained base flow, driven by a more prolonged snowmelt period, and greater runoff during small events. The annual flow differential had a strong positive correlation to maximum snow water equivalent, suggesting that differences in snow accumulation may explain the flow differential. We are investigating whether these differences are a direct consequence of management activities and resulting vegetation shifts and land clearing on snow capture. Several of the highest peak flows in both watersheds have occurred in the last 2 years of the 11-yr study. Our analysis is aimed at determining whether absolute peak flows have increased disproportionately at West Branch relative to the overall flow differential. As actual pre- and post-expansion flows differ markedly from design projections, our study also bears out the need for science-based management decisions.

Climate Change and Human Disturbance Can Lead to Local Extinction of Alpine Rock Ptarmigan: New Insight from the Western Italian Alps

PubMed Central

Imperio, Simona; Bionda, Radames; Viterbi, Ramona; Provenzale, Antonello

2013-01-01

Alpine grouses are particularly vulnerable to climate change due to their adaptation to extreme conditions and to their relict distributions in the Alps where global warming has been particularly marked in the last half century. Grouses are also currently threatened by habitat modification and human disturbance, and an assessment of the impact of multiple stressors is needed to predict the fate of Alpine populations of these birds in the next decades. We estimated the effect of climate change and human disturbance on a rock ptarmigan population living in the western Italian Alps by combining an empirical population modelling approach and stochastic simulations of the population dynamics under the a1B climate scenario and two different disturbance scenarios, represented by the development of a ski resort, through 2050.The early appearance of snow-free ground in the previous spring had a favorable effect on the rock ptarmigan population, probably through a higher reproductive success. On the contrary, delayed snowfall in autumn had a negative effect possibly due to a mismatch in time to molt to white winter plumage which increases predation risk. The regional climate model PROTHEUS does not foresee any significant change in snowmelt date in the study area, while the start date of continuous snow cover is expected to be significantly delayed. The net effect in the stochastic projections is a more or less pronounced (depending on the model used) decline in the studied population. The addition of extra-mortality due to collision with ski-lift wires led the population to fatal consequences in most projections. Should these results be confirmed by larger studies the conservation of Alpine populations would deserve more attention. To counterbalance the effects of climate change, the reduction of all causes of death should be pursued, through a strict preservation of the habitats in the present area of occurrence. PMID:24260581

Climate change and human disturbance can lead to local extinction of Alpine rock ptarmigan: new insight from the western Italian Alps.

PubMed

Imperio, Simona; Bionda, Radames; Viterbi, Ramona; Provenzale, Antonello

2013-01-01

Alpine grouses are particularly vulnerable to climate change due to their adaptation to extreme conditions and to their relict distributions in the Alps where global warming has been particularly marked in the last half century. Grouses are also currently threatened by habitat modification and human disturbance, and an assessment of the impact of multiple stressors is needed to predict the fate of Alpine populations of these birds in the next decades. We estimated the effect of climate change and human disturbance on a rock ptarmigan population living in the western Italian Alps by combining an empirical population modelling approach and stochastic simulations of the population dynamics under the a1B climate scenario and two different disturbance scenarios, represented by the development of a ski resort, through 2050.The early appearance of snow-free ground in the previous spring had a favorable effect on the rock ptarmigan population, probably through a higher reproductive success. On the contrary, delayed snowfall in autumn had a negative effect possibly due to a mismatch in time to molt to white winter plumage which increases predation risk. The regional climate model PROTHEUS does not foresee any significant change in snowmelt date in the study area, while the start date of continuous snow cover is expected to be significantly delayed. The net effect in the stochastic projections is a more or less pronounced (depending on the model used) decline in the studied population. The addition of extra-mortality due to collision with ski-lift wires led the population to fatal consequences in most projections. Should these results be confirmed by larger studies the conservation of Alpine populations would deserve more attention. To counterbalance the effects of climate change, the reduction of all causes of death should be pursued, through a strict preservation of the habitats in the present area of occurrence.

Paralympic medical services for the 2010 paralympic winter games.

PubMed

Taunton, Jack; Wilkinson, Michael; Celebrini, Rick; Stewart, Robert; Stasyniuk, Treny; Van de Vliet, Peter; Willick, Stuart; Ferrer, Josep Martinez

2012-01-01

To present the planning and medical encounters for the 2010 Paralympic Winter Games. Prospective medical encounter study. 2010 Paralympic Winter Games. Athletes, coaches, officials, workforce, volunteers, and media. Sport type: alpine, Nordic, and sledge hockey and curling. Participant type: athlete, workforce, and spectators. Terrain and speed. Medical encounters entered in database at competitive (alpine skiing, biathlon, cross-country skiing, sledge hockey, and curling) and noncompetitive (Whistler and Vancouver Polyclinics, presentation centers, opening and closing ceremonies, media center, Paralympic Family Hotel) venues. Forty-two nations participated with 1350 Paralympic athletes, coaches, and officials. There were 2590 accredited medical encounters (657 athletes, 25.4%; 682 International Federation/National Paralympic Committee officials, 26.3%; 57 IPC, 2.2%; 8 media, 0.3%; 1075 workforce, 41.5%; 111 others, 4.3%) and 127 spectator encounters for a total of 2717 encounters. During the preopening period medical services saw 201 accredited personnel. The busiest venues during the Paralympic Games were the Whistler (1633 encounters) and Vancouver (748 encounters) Polyclinics. Alpine, sledge hockey, and curling were the busiest competitive venues. The majority of medical encounters were musculoskeletal (44.6%, n = 1156). Medical services recorded 1657 therapy treatments, 977 pharmaceutical prescriptions dispensed, 204 dental treatments, 353 imaging examinations (more than 50% from alpine skiing), and 390 laboratory tests. There were 24 ambulance transfers with 7 inpatient hospitalizations for a total of 24 inpatient days and 4 outpatient visits. The mandate to have minimal impact on the health services of Vancouver and the Olympic Corridor while offering excellent medical services to the Games was accomplished. This data will be valuable to future organizing committees.

Multi-Axis Prosthetic Knee Resembles Alpine Skiing Movements of an Intact Leg

PubMed Central

Demšar, Ivan; Duhovnik, Jože; Lešnik, Blaž; Supej, Matej

2015-01-01

The purpose of the study was to analyse the flexion angles of the ski boot, ankle and knee joints of an above-knee prosthesis and to compare them with an intact leg and a control group of skiers. One subject with an above-knee amputation of the right leg and eight healthy subjects simulated the movement of a skiing turn by performing two-leg squats in laboratory conditions. By adding additional loads in proportion to body weight (BW; +1/3 BW, +2/3 BW, +3/3 BW), various skiing regimes were simulated. Change of Flexion Angle (CoFA) and Range of Motion (RoM) in the ski boot, ankle and knee joints were calculated and compared. An average RoM in the skiing boot on the side of prosthesis (4.4 ± 1.1°) was significantly lower compared to an intact leg (5.9 ± 1.8°) and the control group (6.5 ± 2.3°). In the ankle joint, the average RoM was determined to be 13.2±2.9° in the prosthesis, 12.7 ± 2.8° in an intact leg and 14.8±3.6 in the control group. However, the RoM of the knee joint in the prosthesis (42.2 ± 4.2°) was significantly larger than that of the intact leg (34.7 ± 4.4°). The average RoM of the knee joint in the control group was 47.8 ± 5.4°. The influences of additional loads on the kinematics of the lower extremities were different on the side of the prosthesis and on the intact leg. In contrast, additional loads did not produce any significant differences in the control group. Although different CoFAs in the ski boot, ankle and knee joints were used, an above-knee prosthesis with a built-in multi-axis prosthetic knee enables comparable leg kinematics in simulated alpine skiing. Key points The RoM in the ski boot on the side of the prosthetic leg was smaller than the RoM of the intact leg and the control group of healthy subjects. The RoM in the ankle joint of prosthetic leg was comparable to that of the intact leg and the control group of healthy subjects. The RoM in the prosthetic knee joint was greater than the RoM in the knee joint of the intact leg and smaller than that of the control group. The total knee flexions in the laboratory measurements were comparable with field measurements. Additional load affects the RoM of the ski boot, ankle and knee joints for the amputated skier in both legs. No significant influence from the additional load was found on the RoM in the control group of healthy subjects. The above-knee prosthesis with a multiple-axis prosthetic knee reproduces the alpine skiing kinematics of an intact leg. PMID:26664282

The injury experience at the 2010 winter paralympic games.

PubMed

Webborn, Nick; Willick, Stuart; Emery, Carolyn A

2012-01-01

The objective of this study was to examine incidence proportion and the characteristics of athlete injuries sustained during the 2010 Vancouver Paralympic Games. Descriptive epidemiological study. All medical venues at the 2010 Vancouver Paralympic Games, Canada. A total of 505 athletes from 44 National Paralympic Committees participating in the 2010 Vancouver Winter Paralympic Games. Baseline covariates included sport specificity (ie, ice sledge hockey, alpine skiing, Nordic skiing, wheelchair curling), gender, age, and disability classification. All injuries that occurred during the 2010 Vancouver Paralympic Games. "Injury" was defined as any sport-related musculoskeletal complaint that caused the athlete to seek medical attention during the study period, regardless of the athlete's ability to continue with training or competition. The Injury Surveillance System identified a total of 120 injuries among 505 athletes [incidence proportion = 23.8% (95% confidence interval, 20.11-27.7)] participating in the 2010 Winter Paralympic Games. There was a similar injury incidence proportion among male (22.8%) and female (26.6%) athletes [incidence rate ratio = 1.1 (95% confidence interval, 0.7-1.7)]. Medical encounters for musculoskeletal complaints were generated in 34% of all sledge hockey athletes, 22% of alpine ski racers, 19% of Nordic skiers, and 18% of wheelchair curling athletes. The Injury Surveillance System identified sport injuries in 24% of all athletes participating in the 2010 Winter Paralympic Games. The injury risk was significantly higher than during the 2002 (9.4%) and 2006 (8.4%) Winter Paralympic Games. This may reflect improved data collection systems but also highlights the high risk of acute injury in alpine skiing and ice sledge hockey at Paralympic Games. These data will assist future Organizing Committees with the delivery of medical care to athletes with a disability and guide future injury prevention research.

The need to consider relative age effects in women's talent development process.

PubMed

Romann, Michael; Fuchslocher, Jörg

2014-06-01

Relative age effects (RAEs) refer to age differences among athletes in the same selection year. This study analyzed birth date distributions of 301,428 female athletes (aged 10-20 yr.) in Swiss Youth sports and the subgroup (n = 1,177) of the National Talent Development Program (TDP) in individual sports. Comparisons showed significant RAEs in the distribution of athletes' birth dates in alpine skiing, tennis, athletics, fencing, and snowboarding. Significant "reverse" RAEs with an overrepresentation of athletes at the end of the year were found in table tennis. In the TDP, significant RAEs were found in alpine skiing and tennis. No RAEs were detected in athletics. In table tennis, fencing, and snowboarding, "reverse" RAEs were found. Clearly, RAEs are complex and vary across individual sports for females.

Methods for acquiring data on terrain geomorphology, course geometry and kinematics of competitors' runs in alpine skiing: a historical review.

PubMed

Erdmann, Włodzimierz S; Giovanis, Vassilis; Aschenbrenner, Piotr; Kiriakis, Vaios; Suchanowski, Andrzej

2017-01-01

This paper aims at the description and comparison of methods of topographic analysis of racing courses at all disciplines of alpine skiing sports for the purposes of obtaining: terrain geomorphology (snowless and with snow), course geometry, and competitors' runs. The review presents specific methods and instruments according to the order of their historical appearance as follows: (1) azimuth method with the use of a compass, tape and goniometer instruments; (2) optical method with geodetic theodolite, laser and photocells; (3) triangulation method with the aid of a tape and goniometer; (4) image method with the use of video cameras; (5) differential global positioning system and carrier phase global positioning system methods. Described methods were used at homologation procedure, at training sessions, during competitions of local level and during International Ski Federation World Championships or World Cups. Some methods were used together. In order to provide detailed data on course setting and skiers' running it is recommended to analyse course geometry and kinematics data of competitors' running for all important competitions.

Intra-articular temperatures of the knee in sports – An in-vivo study of jogging and alpine skiing

PubMed Central

Becher, Christoph; Springer, Jan; Feil, Sven; Cerulli, Guiliano; Paessler, Hans H

2008-01-01

Background Up to date, no information exists about the intra-articular temperature changes of the knee related to activity and ambient temperature. Methods In 6 healthy males, a probe for intra-articular measurement was inserted into the notch of the right knee. Each subject was jogging on a treadmill in a closed room at 19°C room temperature and skiing in a ski resort at -3°C outside temperature for 60 minutes. In both conditions, temperatures were measured every fifteen minutes intra-articulary and at the skin surface of the knee. A possible influence on joint function and laxity was evaluated before and after activity. Statistical analysis of intra-articular and skin temperatures was done using nonparametric Wilcoxon's sign rank sum test and Mann-Whitney's-U-Test. Results Median intra-articular temperatures increased from 31.4°C before activity by 2.1°C, 4°C, 5.8°C and 6.1°C after 15, 30, 45 and 60 min of jogging (all p ≤ 0.05). Median intra-articular temperatures dropped from 32.2°C before activity by 0.5°C, 1.9°C, 3.6°C and 1.1°C after 15, 30, 45 and 60 min of skiing (all n.s.). After 60 minutes of skiing (jogging), the median intra-articular temperature was 19.6% (8.7%) higher than the skin surface temperature at the knee. Joint function and laxity appeared not to be different before and after activity within both groups. Conclusion This study demonstrates different changes of intra-articular and skin temperatures during sports in jogging and alpine skiing and suggests that changes are related to activity and ambient temperature. PMID:18405365

Tourism and Water: Themes of the Alpine Convention

NASA Astrophysics Data System (ADS)

Imhof, R.

2012-04-01

1) The contribution reflects the personal opinion of the author and does not necessarily reflect the point of view of the Permanent Secretariat. The Alpine Convention is a multilateral framework treaty signed in 1991 by the eight states of the Alpine bow as well as the European Community. Its main objectives are the sustainable development of the Alpine territory and the safeguarding of the interests of the people living within it, embracing the environmental, social and economic dimensions in the broadest sense. In order to achieve its objectives, over the years the Framework Convention has been equipped with a large number of thematic protocols, e.g. on tourism. The overall objective of the Protocol on Tourism, which first came into force in 2002, is to contribute to sustainable development in the Alpine region within the existing institutional framework, by encouraging environmentally-friendly tourism through specific measures and recommendations which take the interests of both the local population and tourists into account. The provisions of the Protocol on Tourism primarily concern tourism management and controlling tourist flows, structural developments such as ski lifts and ski slopes, accommodation and the balanced development of economically weak areas. Guidelines, development plans, sectoral plans have to be adopted at the appropriate territorial level in order to enable to assess the impact of tourism development on, inter alia, water. This extends also to ski slopes developments. For example the production of artificial snow production may be authorized only if the location's hydrological, climatic and ecological conditions allow. Water is listed among the twelve themes in relation to which the Contracting Parties are supposed to take measures and coordinate their policies (Article 2 of the Framework Convention). The Alpine Convention aims to preserve and re-establish healthy water systems, especially keeping waters clean and protecting the natural environment. This needs to be accomplished by balancing the local population's interests with environmental needs. Water is considered as a crucial element for different uses such as hydroelectricity production, irrigation or drinking water as well as in biotopes, especially forests, environmental regeneration and diversity and in natural and cultural landscapes features. Aspects of water protection can be found in the protocols on Energy, Nature Conservation and Landscape Protection, Soil Protection, Tourism, Spatial Planning and Sustainable Development, Mountain Agriculture, Mountain Forests and Transport. However a specific protocol on water is not in place. The Reports on the state of the Alps are published regularly by the Alpine Conference. In November 2006 water was chosen as the topic for the second Report on the State of the Alps. The report compiles information from the Alpine Countries on monitoring programmes, chemical quality of water (point sources, diffuse sources and the chemical status of surface and groundwater in the Alps), water abstraction, residual water and hydro-peaking, droughts and water scarcity, reservoirs and regulated lakes as well on river morphology and continuity. Finally, it summarizes information on property rights and provisions for access to water in the different countries, charges regarding the use of water, different management systems for water supply (public or private), hydro power generation in the Alps and water use management conflicts. The Report was adopted by the Ministers during the Xth Alpine Conference in Evian (France) in 2009. This Conference additionally set up a platform on Water management in the Alpine area in order to deal continually with the theme of water in the Alps. Within this platform, objectives that were identified in the second Report on the State of the Alps should be pursued and examples of good practices exchanged. The platform developed inter alia common guidelines for the use of small hydropower in the Alpine region, which were adopted by the XIth Alpine Conference in Brdo (Slovenia) in 2011. Next tasks for the water platform and follow up will be identified at the XIIth Alpine Conference in September 2012 in Poschiavo, Switzerland. Further, at this conference the fourth Report on the State of the Alps on "Sustainable tourism in the Alps" should be adopted as well.

Myths Concerning Alpine Skiing Injuries

PubMed Central

Johnson, Robert J.; Ettlinger, Carl F.; Shealy, Jasper E.

2009-01-01

There are many commonly discussed myths about ski safety that are propagated by industry, physicians, and skiers. Through a review of the literature concerning 12 such topics, this article demonstrates that the following are untrue: (1) Broken legs have been traded for blown-out knees. (2) If you know your DIN (a slang term for release indicator value), you can adjust your own bindings. (3) Toe and heel piece settings must be the same to function properly. (4) Formal ski instruction will make you safer. (5) Very short skis do not need release bindings. (6) Spending a lot of money on children’s equipment is not worth the cost. (7) Children need plenty of room in ski boots for their growing feet. (8) If you think you are going to fall, just relax. (9) Exercise can prevent skiing injuries. (10) Lower release settings can reduce the risk of anterior cruciate ligament injury. (11) Buying new ski equipment is safer than renting. (12) Skiing is among the most dangerous of activities. It is important for the skiing public, physicians, and all those interested in improving skiing safety to verify the measures they advocate. The statements analyzed here are simply untrue and have the potential to cause harm if taken as fact by those exposed to these unsupported opinions. PMID:23015911

An Inertial Sensor-Based Method for Estimating the Athlete's Relative Joint Center Positions and Center of Mass Kinematics in Alpine Ski Racing

PubMed Central

Fasel, Benedikt; Spörri, Jörg; Schütz, Pascal; Lorenzetti, Silvio; Aminian, Kamiar

2017-01-01

For the purpose of gaining a deeper understanding of the relationship between external training load and health in competitive alpine skiing, an accurate and precise estimation of the athlete's kinematics is an essential methodological prerequisite. This study proposes an inertial sensor-based method to estimate the athlete's relative joint center positions and center of mass (CoM) kinematics in alpine skiing. Eleven inertial sensors were fixed to the lower and upper limbs, trunk, and head. The relative positions of the ankle, knee, hip, shoulder, elbow, and wrist joint centers, as well as the athlete's CoM kinematics were validated against a marker-based optoelectronic motion capture system during indoor carpet skiing. For all joints centers analyzed, position accuracy (mean error) was below 110 mm and precision (error standard deviation) was below 30 mm. CoM position accuracy and precision were 25.7 and 6.7 mm, respectively. Both the accuracy and precision of the system to estimate the distance between the ankle of the outside leg and CoM (measure quantifying the skier's overall vertical motion) were found to be below 11 mm. Some poorer accuracy and precision values (below 77 mm) were observed for the athlete's fore-aft position (i.e., the projection of the outer ankle-CoM vector onto the line corresponding to the projection of ski's longitudinal axis on the snow surface). In addition, the system was found to be sensitive enough to distinguish between different types of turns (wide/narrow). Thus, the method proposed in this paper may also provide a useful, pervasive way to monitor and control adverse external loading patterns that occur during regular on-snow training. Moreover, as demonstrated earlier, such an approach might have a certain potential to quantify competition time, movement repetitions and/or the accelerations acting on the different segments of the human body. However, prior to getting feasible for applications in daily training, future studies should primarily focus on a simplification of the sensor setup, as well as a fusion with global navigation satellite systems (i.e., the estimation of the absolute joint and CoM positions). PMID:29163196

An Inertial Sensor-Based Method for Estimating the Athlete's Relative Joint Center Positions and Center of Mass Kinematics in Alpine Ski Racing.

PubMed

Fasel, Benedikt; Spörri, Jörg; Schütz, Pascal; Lorenzetti, Silvio; Aminian, Kamiar

2017-01-01

For the purpose of gaining a deeper understanding of the relationship between external training load and health in competitive alpine skiing, an accurate and precise estimation of the athlete's kinematics is an essential methodological prerequisite. This study proposes an inertial sensor-based method to estimate the athlete's relative joint center positions and center of mass (CoM) kinematics in alpine skiing. Eleven inertial sensors were fixed to the lower and upper limbs, trunk, and head. The relative positions of the ankle, knee, hip, shoulder, elbow, and wrist joint centers, as well as the athlete's CoM kinematics were validated against a marker-based optoelectronic motion capture system during indoor carpet skiing. For all joints centers analyzed, position accuracy (mean error) was below 110 mm and precision (error standard deviation) was below 30 mm. CoM position accuracy and precision were 25.7 and 6.7 mm, respectively. Both the accuracy and precision of the system to estimate the distance between the ankle of the outside leg and CoM (measure quantifying the skier's overall vertical motion) were found to be below 11 mm. Some poorer accuracy and precision values (below 77 mm) were observed for the athlete's fore-aft position (i.e., the projection of the outer ankle-CoM vector onto the line corresponding to the projection of ski's longitudinal axis on the snow surface). In addition, the system was found to be sensitive enough to distinguish between different types of turns (wide/narrow). Thus, the method proposed in this paper may also provide a useful, pervasive way to monitor and control adverse external loading patterns that occur during regular on-snow training. Moreover, as demonstrated earlier, such an approach might have a certain potential to quantify competition time, movement repetitions and/or the accelerations acting on the different segments of the human body. However, prior to getting feasible for applications in daily training, future studies should primarily focus on a simplification of the sensor setup, as well as a fusion with global navigation satellite systems (i.e., the estimation of the absolute joint and CoM positions).

The Use of Body Worn Sensors for Detecting the Vibrations Acting on the Lower Back in Alpine Ski Racing.

PubMed

Spörri, Jörg; Kröll, Josef; Fasel, Benedikt; Aminian, Kamiar; Müller, Erich

2017-01-01

This study explored the use of body worn sensors to evaluate the vibrations that act on the human body in alpine ski racing from a general and a back overuse injury prevention perspective. In the course of a biomechanical field experiment, six male European Cup-level athletes each performed two runs on a typical giant slalom (GS) and slalom (SL) course, resulting in a total of 192 analyzed turns. Three-dimensional accelerations were measured by six inertial measurement units placed on the right and left shanks, right and left thighs, sacrum, and sternum. Based on these data, power spectral density (PSD; i.e., the signal's power distribution over frequency) was determined for all segments analyzed. Additionally, as a measure expressing the severity of vibration exposure, root-mean-square (RMS) acceleration acting on the lower back was calculated based on the inertial acceleration along the sacrum's longitudinal axis. In both GS and SL skiing, the PSD values of the vibrations acting at the shank were found to be largest for frequencies below 30 Hz. While being transmitted through the body, these vibrations were successively attenuated by the knee and hip joint. At the lower back (i.e., sacrum sensor), PSD values were especially pronounced for frequencies between 4 and 10 Hz, whereas a corresponding comparison between GS and SL revealed higher PSD values and larger RMS values for GS. Because vibrations in this particular range (i.e., 4 to 10 Hz) include the spine's resonant frequency and are known to increase the risk of structural deteriorations/abnormalities of the spine, they may be considered potential components of mechanisms leading to overuse injuries of the back in alpine ski racing. Accordingly, any measure to control and/or reduce such skiing-related vibrations to a minimum should be recognized and applied. In this connection, wearable sensor technologies might help to better monitor and manage the overall back overuse-relevant vibration exposure of athletes in regular training and or competition settings in the near future.

Influence of slope steepness, foot position and turn phase on plantar pressure distribution during giant slalom alpine ski racing.

PubMed

Falda-Buscaiot, Thomas; Hintzy, Frédérique; Rougier, Patrice; Lacouture, Patrick; Coulmy, Nicolas

2017-01-01

The purpose of this study was to investigate the evolution of ground reaction force during alpine skiing turns. Specifically, this study investigated how turn phases and slope steepness affected the whole foot normal GRF pattern while performing giant slalom turns in a race-like setting. Moreover, the outside foot was divided into different plantar regions to see whether those parameters affected the plantar pressure distribution. Eleven skiers performed one giant slalom course at race intensity. Runs were recorded synchronously using a video camera in the frontal plane and pressure insoles under both feet's plantar surface. Turns were divided according to kinematic criteria into four consecutive phases: initiation, steering1, steering2 and completion; both steering phases being separated by the gate passage. Component of the averaged Ground Reaction Force normal to the ski's surface([Formula: see text], /BW), and Pressure Time Integral relative to the entire foot surface (relPTI, %) parameters were calculated for each turn phases based on plantar pressure data. Results indicated that [Formula: see text] under the total foot surface differed significantly depending on the slope (higher in steep sections vs. flat sections), and the turn phase (higher during steering2 vs. three other phases), although such modifications were observable only on the outside foot. Moreover, [Formula: see text] under the outside foot was significantly greater than under the inside foot.RelPTI under different foot regions of the outside foot revealed a global shift from forefoot loading during initiation phase, toward heel loading during steering2 phase, but this was dependent on the slope studied. These results suggest a differentiated role played by each foot in alpine skiing turns: the outside foot has an active role in the turning process, while the inside foot may only play a role in stability.

Flow visualisation of downhill skiers using the lattice Boltzmann method

NASA Astrophysics Data System (ADS)

Asai, Takeshi; Hong, Sungchan; Ijuin, Koichi

2017-03-01

In downhill alpine skiing, skiers often exceed speeds of 120 km h-1, with air resistance substantially affecting the overall race times. To date, studies on air resistance in alpine skiing have used wind tunnels and actual skiers to examine the relationship between the gliding posture and magnitude of drag and for the design of skiing equipment. However, these studies have not revealed the flow velocity distribution and vortex structure around the skier. In the present study, computational fluid dynamics are employed with the lattice Boltzmann method to derive the relationship between total drag and the flow velocity around a downhill skier in the full-tuck position. Furthermore, the flow around the downhill skier is visualised, and its vortex structure is examined. The results show that the total drag force in the downhill skier model is 27.0 N at a flow velocity of 15 m s-1, increasing to 185.8 N at 40 m s-1. From analysis of the drag distribution and the flow profile, the head, upper arms, lower legs, and thighs (including buttocks) are identified as the major sources of drag on a downhill skier. Based on these results, the design of suits and equipment for reducing the drag from each location should be the focus of research and development in ski equipment. This paper describes a pilot study that introduces undergraduate students of physics or engineering into this research field. The results of this study are easy to understand for undergraduate students.

Standing Height as a Prevention Measure for Overuse Injuries of the Back in Alpine Ski Racing: A Kinematic and Kinetic Study of Giant Slalom

PubMed Central

Spörri, Jörg; Kröll, Josef; Fasel, Benedikt; Aminian, Kamiar; Müller, Erich

2018-01-01

Background: In alpine ski racing, typical loading patterns of the back include a combined occurrence of spinal bending, torsion, and high peak loads. These factors are known to be associated with high spinal disc loading and have been suggested to be attributable to different types of spine deterioration. However, little is known about the effect of standing height (ie, the distance between the bottom of the running surface of the ski and the ski boot sole) on the aforementioned back loading patterns. Purpose: To investigate the effect of reduced standing height on the skier’s overall trunk kinematics and the acting ground-reaction forces in giant slalom (GS) from an overuse injury prevention perspective. Study Design: Controlled laboratory study. Methods: Seven European Cup–level athletes skied a total of 224 GS turns with 2 different pairs of skis varying in standing height. Their overall trunk movement (frontal bending, lateral bending, and torsion angles) was measured based on 2 inertial measurement units located at the sacrum and sternum. Pressure insoles were used to determine the total ground-reaction force. Results: During the turn phase in which the greatest spinal disc loading is expected to occur, significantly lower total ground-reaction forces were observed for skis with a decreased standing height. Simultaneously, the skier’s overall trunk movement (ie, frontal bending, lateral bending, and torsion angles) remained unwaveringly high. Conclusion: Standing height is a reasonable measure to reduce the skier’s overall back loading in GS. Yet, when compared with the effects achievable by increased gate offsets in slalom, for instance, the preventative benefits of decreased standing height seem to be rather small. Clinical Relevance: To reduce the magnitude of overall back loading in GS and to prevent overuse injuries of the back, decreasing standing height might be an efficient approach. Nevertheless, the clinical relevance of the current findings, as well as the effectiveness of the measure “reduced standing height,” must be verified by epidemiological studies before its preventative potential can be judged as conclusive. PMID:29344540

Erythropoietin, 2,3 DPG, oxygen transport capacity, and altitude training in adolescent Alpine skiers.

PubMed

Son, Hee Jeong; Kim, Hyo Jeong; Kim, Jin Hae; Ohno, Hideki; Kim, Chang Keun

2012-01-01

Rapid growth during adolescence caused by metabolic changes and their metabolic response to anaerobic and aerobic exercise differs considerably from that in adults and this is especially true in the responses to stresses, such as altitude exposure. However, there is little information on the suitability of exercise training at altitude for young athletes. Six male Korean adolescent alpine skiers (13-17 yr), with a skiing career of 3-5 yr, participated in the study. All subjects were exposed to an altitude of 2700 m (8858 ft) for 5 wk and altitude exposure consisted of 6 d/wk of training (4-5 h/d), with living quarters at 2100 m (-6890 ft) (Tignes, France). The 5 wk of ski training at altitude were maintained at the same level (the same number of slalom and giant slalom skiing trials) as at sea level. There was a significant increase in oxygen transport capacity, despite decreased erythropoietin (EPO) production (-31%) after altitude training. Red blood cell (RBC), hemoglobin (Hb), hematocrit (Hct), and 2,3 DPG concentrations increased significantly during altitude exposure and after return to sea level. Results indicate that applying altitude training in adolescent skiers may improve their endurance performance. However, EPO production during altitude training needs to be evaluated in larger future studies.

[Skiing injuries in school sport and possibilioties to prevent them].

PubMed

Greier, K

2011-12-01

Tyrol (Austria) is one of the regions which pioneered skiing. Skiing is considered as a national sport and is deeply rooted within the school system. Thus most pupils partake in skiing courses in this period. It is clear that such a large group of pupils also leads to a significant number of skiing injuries. Preventive issues may be derived from an analysis of the pattern and circumstances of skiing injuries. During a period of ten years (2000 - 2009) 1522 school sports injuries have been reported to the health insurance agency (Allgemeine Unfallversicherungsanstalt) from all secondary schools in Tyrol. The major disciplines were ski (48 %, n = 734) ice skateing (23 %, n = 349) and snowboard injuries (21 %, n = 315), followed by tobogganing (6 %, n = 91), cross-country skiing (1 %, n = 17) and other wintersports (1 %, n = 16). Fractures (31 %) dominated in skiing, followed by contusions (23 %), and sprains (22 %). In the analysis of the distribution of injuries during alpine skiing accidents, lower extremity injuries (39 %) dominated followed by upper extremity injuries (34 %). Head and spine injuries (13 %) were rare. Analysing the circumstances of the injuries, most injuries during skiing occurred without person to person collision (82 %), 81 % either shortly before lunch-break or in the afternoon. Skiing injuries account for a significant proportion of all school sport-related injuries in Tyrol. Lower extremity injuries account for the vast majority of all injuries. Overestimation and overtiredness may be responsible for skiing sport injuries. Preventive measures such as a fitness training (e. g., skiing exercises) prior to skiing courses, appropriate breaks and proper protective gear (i. e., helmet and spine protector) may reduce the injury rate in skiing school sport. © Georg Thieme Verlag KG Stuttgart · New York.

PROSNOW - Provision of a prediction system allowing for management and optimization of snow in Alpine ski resorts

NASA Astrophysics Data System (ADS)

Morin, Samuel; Ghislain, Dubois

2017-04-01

Snow on the ground is a critical resource for mountain regions to sustain river flow, to provide freshwater input to ecosystems and to support winter tourism, in particular in ski resorts. The level of activity, employment, turnover and profit of hundreds of ski resorts in the European Alps primarily depends on meteorological conditions, in particular natural snowfall but also increasingly conditions favourable for snowmaking (production of machine made snow, also referred to as technical snow). Ski resorts highly depend on appropriate conditions for snowmaking (mainly the availability of cold water, as well as sub-freezing temperature with sufficiently low humidity conditions). However, beyond the time scale of weather forecasts (a few days), managers of ski resorts have to rely on various and scattered sources of information, hampering their ability to cope with highly variable meteorological conditions. Improved anticipation capabilities at all time scales, spanning from "weather forecast" (up to 5 days typically) to "climate prediction" at the seasonal scale (up to several months) holds significant potential to increase the resilience of socio-economic stakeholders and supports their real-time adaptation potential. To address this issue, the recently funded (2017-2020) H2020 PROSNOW project will build a demonstrator of a meteorological and climate prediction and snow management system from one week to several months ahead, specifically tailored to the needs of the ski industry. PROSNOW will apply state-of-the-art knowledge relevant to the predictability of atmospheric and snow conditions, and investigate and document the added value of such services. The project proposes an Alpine-wide system (including ski resorts located in France, Switzerland, Germany, Austria and Italy). It will join and link providers of weather forecasts and climate predictions at the seasonal scale, research institutions specializing in snowpack modelling, a relevant ensemble of at least 8 representative resorts in the Alps, technical bodies representing ski resorts managers, and private technology companies. These companies are already providing services for snow management such as snow depth monitoring, snowmaking operations monitoring and planning using latest technologies. The added value of the demonstrator will be assessed for the ski industry, but also for additional stakeholders including local and regional tourism authorities, hydropower managers, and natural hazard forecasters and planners. This presentation will introduce the main goals and concepts of the PROSNOW project, in order to foster interactions with the specialized scientific communities relevant to this challenge.

Commodifying snow, taming the waters. Socio-ecological niche construction in an Alpine village.

PubMed

Gross, Robert; Winiwarter, Verena

White belts of snow clad mountains all over the world each winter. Even if there is no snow, the tourism industry is able to produce the white finery at the push of the button, thereby consuming large amounts of water. Studying Damüls, a well-known ski resort in Austria's westernmost province Vorarlberg, we can show that the development of a service sector within agro-pastoral landscapes was connected with novel water uses and massive interventions into Alpine landscapes. Human niche construction theory offers a unique avenue for studying the development of Alpine communities, but also highlights side effects accompanying the change from agrarian to tourism livelihoods. One aim of this paper is to broaden the scope of human niche construction theory. Inceptive, counteractive and relocational niche construction activities were coupled to the differentiation of actor groups. To incorporate social dynamics, indispensable for studies in environmental history, we propose the concept of socio-ecological niche construction. The paper investigates how villagers balanced resource limitations typical for an agrarian society with the differentiation of sub-niches, mediating selective forces on the population. When the valleys were industrialized, Damüls was almost given up as a permanent settlement. Then, tourists entered the stage, by and by turning the wheel of local development into a different direction. A tourism niche based on natural snow evolved from the 1930s onwards. While the socio-ecological niches of agriculture and tourism coexisted in the interwar years, this changed when ski lifts were built, embedded into a debt-based economy that made the tourism niche vulnerable to snow availability. Snow-dependency became a powerful selective force. It was mediated by the ski lift companies through a range of niche construction activities that turned water into an important resource of snowmaking systems.

Effect of ski geometry on aggressive ski behaviour and visual aesthetics: equipment designed to reduce risk of severe traumatic knee injuries in alpine giant slalom ski racing

PubMed Central

Kröll, Josef; Spörri, Jörg; Gilgien, Matthias; Schwameder, Hermann; Müller, Erich

2016-01-01

Background/Aim Aggressive ski-snow interaction is characterised by direct force transmission and difficulty of getting the ski off its edge once the ski is carving. This behaviour has been suggested to be a main contributor to severe knee injuries in giant slalom (GS). The aim of the current study was to provide a foundation for new equipment specifications in GS by considering two perspectives: Reducing the ski's aggressiveness for injury prevention and maintaining the external attractiveness of a ski racer's technique for spectators. Methods Three GS ski prototypes were defined based on theoretical considerations and were compared to a reference ski (Pref). Compared to Pref, all prototypes were constructed with reduced profile width and increased ski length. The construction radius (sidecut radius) of Pref was ≥27 m and was increased for the prototypes: 30 m (P30), 35 m (P35), and 40 m (P40). Seven World Cup level athletes performed GS runs on each of the three prototypes and Pref. Kinetic variables related to the ski-snow interaction were assessed to quantify the ski's aggressiveness. Additionally, 13 athletes evaluated their subjective perception of aggressiveness. 15 sports students rated several videotaped runs to assess external attractiveness. Results Kinetic variables quantifying the ski's aggressiveness showed decreased values for P35 and P40 compared to Pref and P30. Greater sidecut radius reduced subjectively perceived aggressiveness. External attractiveness was reduced for P40 only. Conclusions This investigation revealed the following evaluation of the prototypes concerning injury prevention and external attractiveness: P30: no preventative gain, no loss in attractiveness; P35: substantial preventative gain, no significant loss in attractiveness; P40: highest preventative gain, significant loss in attractiveness. PMID:26603647

Earth observations during STS-89

NASA Image and Video Library

1998-01-30

STS089-709-049 (22-31 Jan. 1998) --- This oblique photograph of Argentina and Chile was among several of South America photographed with a 70mm handheld camera from the Earth-orbiting space shuttle Endeavour. This part of Patagonia in Argentina and the lake district of Chile and Argentina are in southern South America between latitudes 40 degrees and 43 degrees. It is a beautiful alpine region noted for skiing and for the recent immigration of rich Americans and Europeans. On the west side of the Andes are a series of snow-capped volcanoes that are formed due to melting of sediments and portions of the Pacific Plate, which are being subducted beneath South America. East of the mountains the plains are barren and windswept, noted as having "the curse of sterility" by Charles Darwin. In the mountain regions some alpine valleys are filled by lovely lakes, such as Nahuel Huapi (in sunglint). The university town and ski resort of Bariloche, Argentina is the light area on the southeastern shore. In 1901 Robert Leroy Parker and Harry Longabaugh (aka Butch Cassidy and Sundance Kid) bought a ranch near the town of Cholila (lower left in the photo) with the proceeds of a robbery of the First National Bank of Winnemucca, Nevada. They lived there as successful ranchers until 1907, when they were reportedly forced to sell out and flee to Bolivia where their career ended at the hands of the Bolivian army. Photo credit: NASA

Skiing Sochi

NASA Image and Video Library

2014-02-19

High res here: www.flickr.com/photos/gsfc/12640339235/in/photostream/ While Sochi is a coastal town on the Black Sea, the skiing events for the XXII Olympic Games are taking place about 40 kilometers (25 miles) inland. The venues are clustered around Krasnaya Polyana, a small town tucked between the Aibiga and Psekhako Ridges in the western Caucasus. This image—acquired by the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite on February 8, 2014—offers a view of the town and the ski facilities. The Rosa Khutor Alpine Center is the home to the downhill, snowboard, and freestyle events. The combined downhill skiing area measures about 20 kilometers (12 miles) in total, with the men’s downhill course stretching 3,500 meters (11,482 feet) and featuring a 1,075-meter (3,526 foot) change in elevation. The highest lift climbs to the summit of Rosa Peak, which rises 2,320 meters (7,612 feet). While not being used for the Olympics, the nearby Black Pyramid mountain has downhill skiing trails as well. The same steep slopes that make Rosa Peak good for skiing also elevate the risk of avalanches. To protect against falling snow, planners installed a series of gas pipes along the top of the ridge. The pipes emit bursts of oxygen and propane that create small, controlled avalanches. Event organizers also installed a series of earthen dams to steer snow away from infrastructure, and they have deployed two backhoes to the top of Aibiga Ridge to knock cornices away before they pose a risk. The Laura Cross-country Ski and Biathalon Center is located to the north on Psekhako Ridge. It includes two stadiums, each with their own start and finish zones, two track systems for skiing and biathlon, as well as shooting areas and warm-up zones. The center is named for the Laura River, a turbulent river that flows nearby. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Adam Voiland. Instrument: EO-1 - ALI Read more: earthobservatory.nasa.gov/IOTD/view.php?id=83131&eocn... Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Skiing Sochi

NASA Image and Video Library

2014-02-19

While Sochi is a coastal town on the Black Sea, the skiing events for the XXII Olympic Games are taking place about 40 kilometers (25 miles) inland. The venues are clustered around Krasnaya Polyana, a small town tucked between the Aibiga and Psekhako Ridges in the western Caucasus. This image—acquired by the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite on February 8, 2014—offers a view of the town and the ski facilities. The Rosa Khutor Alpine Center is the home to the downhill, snowboard, and freestyle events. The combined downhill skiing area measures about 20 kilometers (12 miles) in total, with the men’s downhill course stretching 3,500 meters (11,482 feet) and featuring a 1,075-meter (3,526 foot) change in elevation. The highest lift climbs to the summit of Rosa Peak, which rises 2,320 meters (7,612 feet). While not being used for the Olympics, the nearby Black Pyramid mountain has downhill skiing trails as well. The same steep slopes that make Rosa Peak good for skiing also elevate the risk of avalanches. To protect against falling snow, planners installed a series of gas pipes along the top of the ridge. The pipes emit bursts of oxygen and propane that create small, controlled avalanches. Event organizers also installed a series of earthen dams to steer snow away from infrastructure, and they have deployed two backhoes to the top of Aibiga Ridge to knock cornices away before they pose a risk. The Laura Cross-country Ski and Biathalon Center is located to the north on Psekhako Ridge. It includes two stadiums, each with their own start and finish zones, two track systems for skiing and biathlon, as well as shooting areas and warm-up zones. The center is named for the Laura River, a turbulent river that flows nearby. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Adam Voiland. Instrument: EO-1 - ALI Read more: earthobservatory.nasa.gov/IOTD/view.php?id=83131&eocn... Credit: NASA Earth Observatory NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Soil nitrogen dynamics in high-altitude ski runs during the winter season (Monterosaski - Vallée d

NASA Astrophysics Data System (ADS)

Freppaz, M.; Icardi, M.; Filippa, G.; Zanini, E.

2009-04-01

In many Alpine catchments, the development of winter tourism determined a widespread change in land use, shifting from forested and cultivated lands to ski slopes. The construction of a ski slope implies a strong impact on the landscape, with potential consequences on the soil quality. In most cases, the construction procedures include the total or partial removal of the soil body, the reallocation of the fine hearth fraction, the subsequent seeding of plants and the use of organic fertilizers. This work aims to evaluate soil physical and chemical properties and nitrogen (N) dynamics in anthropogenic soils from ski slopes of different age. Study sites were located in Champoluc (AO)- NW Italy between 2400 and 2700 m ASL. Topsoils (0-10 cm depth) were sampled in 4 ski slopes hydroseeded with commercial mixtures 4, 6, 10 and 12 years earlier, and in 4 control plots at the same exposure and altitude as the ski slopes. Soil samples were characterized, N dynamics in winter was evaluated with the buried bag technique and snowpack was analyzed for chemical and physical properties. Total nitrogen (TN) content in topsoil ranged 0.75-1.06 g kg-1 and was not correlated with the ski slope age. In all but one site, the TN content was significantly lower in the ski slope than in the control plot. A positive net ammonification and nitrification throughout the winter were found in all but one ski runs. These results suggest a high variability in the evolution degree of these anthropogenic soils. The net overwinter N mineralization that we report demonstrates that these soils are biologically active during the winter season. Such activity results in a pool of labile inorganic nitrogen potentially available for plant demand at the spring snowmelt.

Effect of ski geometry and standing height on kinetic energy: equipment designed to reduce risk of severe traumatic injuries in alpine downhill ski racing.

PubMed

Gilgien, Matthias; Spörri, Jörg; Kröll, Josef; Müller, Erich

2016-01-01

Injuries in downhill (DH) are often related to high speed and, therefore, to high energy and forces which are involved in injury situations. Yet to date, no study has investigated the effect of ski geometry and standing height on kinetic energy (EKIN) in DH. This knowledge would be essential to define appropriate equipment rules that have the potential to protect the athletes' health. During a field experiment on an official World Cup DH course, 2 recently retired world class skiers skied on 5 different pairs of skis varying in width, length and standing height. Course characteristics, terrain and the skiers' centre of mass position were captured by a differential Global Navigational Satellite System-based methodology. EKIN, speed, ski-snow friction force (FF), ground reaction force (FGRF) and ski-snow friction coefficient (CoeffF) were calculated and analysed in dependency of the used skis. In the steep terrain, longer skis with reduced width and standing height significantly decreased average EKIN by ∼ 3%. Locally, even larger reductions of EKIN were observed (up to 7%). These local decreases in EKIN were mainly explainable by higher FF. Moreover, CoeffF differences seem of greater importance for explaining local FF differences than the differences in FGRF. Knowing that increased speed and EKIN likely lead to increased forces in fall/crash situations, the observed equipment-induced reduction in EKIN can be considered a reasonable measure to improve athlete safety, even though the achieved preventative gains are rather small and limited to steep terrain. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Confronting the demand and supply of snow seasonal forecasts for ski resorts : the case of French Alps

NASA Astrophysics Data System (ADS)

Dubois, Ghislain

2017-04-01

Alpine ski resorts are highly dependent on snow, which availability is characterized by a both a high inter-annual variability and a gradual diminution due to climate change. Due to this dependency to climatic resources, the ski industry is increasingly affected by climate change: higher temperatures limit snow falls, increase melting and limit the possibilities of technical snow making. Therefore, since the seventies, managers drastically improved their practices, both to adapt to climate change and to this inter-annual variability of snow conditions. Through slope preparation and maintenance, snow stock management, artificial snow making, a typical resort can approximately keep the same season duration with 30% less snow. The ski industry became an activity of high technicity The EUPORIAS FP7 (www.euporias.eu) project developed between 2012 and 2016 a deep understanding of the supply and demand conditions for the provision of climate services disseminating seasonal forecasts. In particular, we developed a case study, which allowed conducting several activities for a better understanding of the demand and of the business model of future services applied to the ski industry. The investigations conducted in France inventoried the existing tools and databases, assessed the decision making process and data needs of ski operators, and provided evidences that some discernable skill of seasonal forecasts exist. This case study formed the basis of the recently funded PROSNOW H2020 project. We will present the main results of EUPORIAS project for the ski industry.

77 FR 39987 - Arapaho and Roosevelt National Forests and Pawnee National Grassland; Boulder and Gilpin County...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

... expectations for a safe, quality, recreational experience by providing appropriate lifts, terrain, and guest... reliability of lift and terrain offerings; (2) address skier safety concerns during prevalent wind events; (3...; (4) provide new and upgraded lift infrastructure to improve the quality of the alpine ski experience...

Influence of slope steepness, foot position and turn phase on plantar pressure distribution during giant slalom alpine ski racing

PubMed Central

Falda-Buscaiot, Thomas; Hintzy, Frédérique; Rougier, Patrice; Lacouture, Patrick; Coulmy, Nicolas

2017-01-01

The purpose of this study was to investigate the evolution of ground reaction force during alpine skiing turns. Specifically, this study investigated how turn phases and slope steepness affected the whole foot normal GRF pattern while performing giant slalom turns in a race-like setting. Moreover, the outside foot was divided into different plantar regions to see whether those parameters affected the plantar pressure distribution. Eleven skiers performed one giant slalom course at race intensity. Runs were recorded synchronously using a video camera in the frontal plane and pressure insoles under both feet’s plantar surface. Turns were divided according to kinematic criteria into four consecutive phases: initiation, steering1, steering2 and completion; both steering phases being separated by the gate passage. Component of the averaged Ground Reaction Force normal to the ski’s surface(nGRF¯, /BW), and Pressure Time Integral relative to the entire foot surface (relPTI, %) parameters were calculated for each turn phases based on plantar pressure data. Results indicated that nGRF¯ under the total foot surface differed significantly depending on the slope (higher in steep sections vs. flat sections), and the turn phase (higher during steering2 vs. three other phases), although such modifications were observable only on the outside foot. Moreover, nGRF¯ under the outside foot was significantly greater than under the inside foot.RelPTI under different foot regions of the outside foot revealed a global shift from forefoot loading during initiation phase, toward heel loading during steering2 phase, but this was dependent on the slope studied. These results suggest a differentiated role played by each foot in alpine skiing turns: the outside foot has an active role in the turning process, while the inside foot may only play a role in stability. PMID:28472092

Block training periodization in alpine skiing: effects of 11-day HIT on VO2max and performance.

PubMed

Breil, Fabio A; Weber, Simone N; Koller, Stefan; Hoppeler, Hans; Vogt, Michael

2010-08-01

Attempting to achieve the high diversity of training goals in modern competitive alpine skiing simultaneously can be difficult and may lead to compromised overall adaptation. Therefore, we investigated the effect of block training periodization on maximal oxygen consumption (VO2max) and parameters of exercise performance in elite junior alpine skiers. Six female and 15 male athletes were assigned to high-intensity interval (IT, N = 13) or control training groups (CT, N = 8). IT performed 15 high-intensity aerobic interval (HIT) sessions in 11 days. Sessions were 4 x 4 min at 90-95% of maximal heart rate separated by 3-min recovery periods. CT continued their conventionally mixed training, containing endurance and strength sessions. Before and 7 days after training, subjects performed a ramp incremental test followed by a high-intensity time-to-exhaustion (tlim) test both on a cycle ergometer, a 90-s high-box jump test as well as countermovement (CMJ) and squat jumps (SJ) on a force plate. IT significantly improved relative VO2max by 6.0% (P < 0.01; male +7.5%, female +2.1%), relative peak power output by 5.5% (P < 0.01) and power output at ventilatory threshold 2 by 9.6% (P < 0.01). No changes occurred for these measures in CT. tlim remained unchanged in both groups. High-box jump performance was significantly improved in males of IT only (4.9%, P < 0.05). Jump peak power (CMJ -4.8%, SJ -4.1%; P < 0.01), but not height decreased in IT only. For competitive alpine skiers, block periodization of HIT offers a promising way to efficiently improve VO2max and performance. Compromised explosive jump performance might be associated with persisting muscle fatigue.

78 FR 38842 - Definition of a Ski Area

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-28

... snow sports. The definition for a ski area in Forest Service regulations at 36 CFR 251.51 implementing... skiing. Accordingly, the Department is amending the definition for a ski area in 36 CFR 251.51 to provide... area in 36 CFR 251.51 that the preponderance of revenue at a ski area derive from activities and...

[How frequent and why are skiers and snowboarders falling?].

PubMed

Philippe, M; Ruedl, G; Feltus, G; Woldrich, T; Burtscher, M

2014-12-01

Injuries in alpine skiing and snowboarding are mainly caused by falls. In 2002, a study was conducted to gain insight into the risk factors for falls when skiing or snowboarding. Since then, the evolution of skiing, snowboarding and safety equipment, as well as slope preparation, may have altered the frequency of falls while skiing or snowboarding. In total, 1436 male and female skiers and snowboarders from all age groups were interviewed from February until April 2012, in 6 Tyrolean ski resorts. The questionnaire was nearly identical to that used in 2002. It contained questions concerning personal characteristics, falls, equipment and risk taking behaviour. The incidence of falls among skiers was 0.076 ± 0.21 per hour and that among snowboarders was 0.429 ± 0.70 per hour. Age (OR: 0.96; CI: 0.95 - 0.97), soft snow conditions (OR: 4.1; CI: 1.9 - 8.8) and poor skiing skills (beginners and intermediates) (OR: 2.6; CI: 1.2 - 8.1) were predictive for falls during skiing. Poor snowboarding skills (beginners and intermediates) (OR: 8.3; CI: 3.1 - 27.4), wearing a helmet (OR: 2.3; CI: 1.2 - 4.6) and alcohol consumption (OR: 2.1; CI: 1.2 - 3.9) were predictive for falls during snowboarding. The incidence of falls among skiers and snowboarders was substantially lower when compared to that in 2002. Improvements in skiing and snowboarding equipment as well as slope preparation may have contributed to this favourable development. We strongly assume that the lowering in fall incidence may positively affect the injury incidence. © Georg Thieme Verlag KG Stuttgart · New York.

Effect of ski geometry and standing height on kinetic energy: equipment designed to reduce risk of severe traumatic injuries in alpine downhill ski racing

PubMed Central

Gilgien, Matthias; Spörri, Jörg; Kröll, Josef; Müller, Erich

2016-01-01

Background Injuries in downhill (DH) are often related to high speed and, therefore, to high energy and forces which are involved in injury situations. Yet to date, no study has investigated the effect of ski geometry and standing height on kinetic energy (EKIN) in DH. This knowledge would be essential to define appropriate equipment rules that have the potential to protect the athletes’ health. Methods During a field experiment on an official World Cup DH course, 2 recently retired world class skiers skied on 5 different pairs of skis varying in width, length and standing height. Course characteristics, terrain and the skiers’ centre of mass position were captured by a differential Global Navigational Satellite System-based methodology. EKIN, speed, ski–snow friction force (FF), ground reaction force (FGRF) and ski–snow friction coefficient (CoeffF) were calculated and analysed in dependency of the used skis. Results In the steep terrain, longer skis with reduced width and standing height significantly decreased average EKIN by ∼3%. Locally, even larger reductions of EKIN were observed (up to 7%). These local decreases in EKIN were mainly explainable by higher FF. Moreover, CoeffF differences seem of greater importance for explaining local FF differences than the differences in FGRF. Conclusions Knowing that increased speed and EKIN likely lead to increased forces in fall/crash situations, the observed equipment-induced reduction in EKIN can be considered a reasonable measure to improve athlete safety, even though the achieved preventative gains are rather small and limited to steep terrain. PMID:26702013

Combining snow depth and innovative skier flow measurements in order to improve snow grooming techniques

NASA Astrophysics Data System (ADS)

Carmagnola, Carlo Maria; Albrecht, Stéphane; Hargoaa, Olivier

2017-04-01

In the last decades, ski resort managers have massively improved their snow management practices, in order to adapt their strategies to the inter-annual variability in snow conditions and to the effects of climate change. New real-time informations, such as snow depth measurements carried out on the ski slopes by grooming machines during their daily operations, have become available, allowing high saving, efficiency and optimization gains (reducing for instance the groomer fuel consumption and operation time and the need for machine-made snow production). In order to take a step forward in improving the grooming techniques, it would be necessary to keep into account also the snow erosion by skiers, which depends mostly on the snow surface properties and on the skier attendance. Today, however, most ski resort managers have only a vague idea of the evolution of the skier flows on each slope during the winter season. In this context, we have developed a new sensor (named Skiflux) able to measure the skier attendance using an infrared beam crossing the slopes. Ten Skiflux sensors have been deployed during the 2016/17 winter season at Val Thorens ski area (French Alps), covering a whole sector of the resort. A dedicated software showing the number of skier passages in real time as been developed as well. Combining this new Skiflux dataset with the snow depth measurements from grooming machines (Snowsat System) and the snow and meteorological conditions measured in-situ (Liberty System from Technoalpin), we were able to create a "real-time skiability index" accounting for the quality of the surface snow and its evolution during the day. Moreover, this new framework allowed us to improve the preparation of ski slopes, suggesting new strategies for adapting the grooming working schedule to the snow quality and the skier attendance. In the near future, this work will benefit from the advances made within the H2020 PROSNOW project ("Provision of a prediction system allowing for management and optimization of snow in Alpine ski resorts"), which has been funded for the period 2017-2020.

Characterization of Course and Terrain and Their Effect on Skier Speed in World Cup Alpine Ski Racing

PubMed Central

Gilgien, Matthias; Crivelli, Philip; Spörri, Jörg; Kröll, Josef; Müller, Erich

2015-01-01

World Cup (WC) alpine ski racing consists of four main competition disciplines (slalom, giant slalom, super-G and downhill), each with specific course and terrain characteristics. The International Ski Federation (FIS) has regulated course length, altitude drop from start to finish and course setting in order to specify the characteristics of the respective competition disciplines and to control performance and injury-related aspects. However to date, no detailed data on course setting and its adaptation to terrain is available. It is also unknown how course and terrain characteristics influence skier speed. Therefore, the aim of the study was to characterize course setting, terrain geomorphology and their relationship to speed in male WC giant slalom, super-G and downhill. The study revealed that terrain was flatter in downhill compared to the other disciplines. In all disciplines, variability in horizontal gate distance (gate offset) was larger than in gate distance (linear distance from gate to gate). In giant slalom the horizontal gate distance increased with terrain inclination, while super-G and downhill did not show such a connection. In giant slalom and super-G, there was a slight trend towards shorter gate distances as the steepness of the terrain increased. Gates were usually set close to terrain transitions in all three disciplines. Downhill had a larger proportion of extreme terrain inclination changes along the skier trajectory per unit time skiing than the other disciplines. Skier speed decreased with increasing steepness of terrain in all disciplines except for downhill. In steep terrain, speed was found to be controllable by increased horizontal gate distances in giant slalom and by shorter gate distances in giant slalom and super-G. Across the disciplines skier speed was largely explained by course setting and terrain inclination in a multiple linear model. PMID:25760039

A New Time Measurement Method Using a High-End Global Navigation Satellite System to Analyze Alpine Skiing

ERIC Educational Resources Information Center

Supej, Matej; Holmberg, Hans-Christer

2011-01-01

Accurate time measurement is essential to temporal analysis in sport. This study aimed to (a) develop a new method for time computation from surveyed trajectories using a high-end global navigation satellite system (GNSS), (b) validate its precision by comparing GNSS with photocells, and (c) examine whether gate-to-gate times can provide more…

Sex Differences in Balance Among Alpine Ski Racers: Cross-Sectional Age Comparisons.

PubMed

Raschner, Christian; Hildebrandt, Carolin; Mohr, Johanna; Müller, Lisa

2017-12-01

Although balance is a key ability in the strength demands of alpine ski racing, affecting both performance and injury prevention, few studies have examined balance or related sex differences among still-maturing athletes. In this 10-year study, we investigated cross-sectional balance performances at different age periods of a representative sample of over 500 11-18-year-old elite skiers of both genders. Participants performed balance tests using the MFT S3-Check. Left-right and forward-backward movements were used to calculate sensory and symmetry balance scores, which were both incorporated into a stability score. Mann-Whitney U tests assessed gender-specific differences by age-group with a significance level set at p < .05. Results showed gender differences only on forward-backward measurements for 14-16-year-olds, with females showing better stability and sensory (but not symmetry) scores than males. Thus, gender interacted with age and maturation to influence balance ability in these participants. Additionally, these rare 10-year data support coaches in their training and talent development of maturing athletes by providing important sport-, age-, and gender-specific normative comparison data for individual trainees.

Sports injuries and illnesses in the Sochi 2014 Olympic Winter Games.

PubMed

Soligard, Torbjørn; Steffen, Kathrin; Palmer-Green, Debbie; Aubry, Mark; Grant, Marie-Elaine; Meeuwisse, Willem; Mountjoy, Margo; Budgett, Richard; Engebretsen, Lars

2015-04-01

Systematic surveillance of injuries and illnesses is the foundation for developing preventive measures in sport. To analyse the injuries and illnesses that occurred during the XXII Olympic Winter Games, held in Sochi in 2014. We recorded the daily occurrence (or non-occurrence) of injuries and illnesses (1) through the reporting of all National Olympic Committee (NOC) medical teams and (2) in the polyclinic and medical venues by the Sochi 2014 medical staff. NOC and Sochi 2014 medical staff reported 391 injuries and 249 illnesses among 2780 athletes from 88 NOCs, equalling incidences of 14 injuries and 8.9 illnesses per 100 athletes over an 18-day period of time. Altogether, 12% and 8% of the athletes incurred at least one injury or illness, respectively. The percentage of athletes injured was highest in aerial skiing, snowboard slopestyle, snowboard cross, slopestyle skiing, halfpipe skiing, moguls skiing, alpine skiing, and snowboard halfpipe. Thirty-nine per cent of the injuries were expected to prevent the athlete from participating in competition or training. Women suffered 50% more illnesses than men. The rate of illness was highest in skeleton, short track, curling, cross-country skiing, figure skating, bobsleigh and aerial skiing. A total of 159 illnesses (64%) affected the respiratory system, and the most common cause of illness was infection (n=145, 58%). Overall, 12% of the athletes incurred at least one injury during the games, and 8% an illness, which is similar to prior Olympic Games. The incidence of injuries and illnesses varied substantially between sports. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

78 FR 21343 - New Ski Area Water Rights Clause

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-10

... DEPARTMENT OF AGRICULTURE Forest Service New Ski Area Water Rights Clause AGENCY: Forest Service... initial public input on a new water rights clause for ski area permits issued by the Forest Service. There... comments and suggestions that the Forest Service will consider in developing a new ski area water rights...

Skiing in the Great Lakes States: the industry and the skier.

Treesearch

William A. Leuschner

1970-01-01

Describes the skiers and ski areas in the Midwest. Analyzes market structure for the industry, the factors associated with financial success, the impact of spending on local economies, and the potential of ski area investment. Includes ski area financial statements.

Application of dGNSS in Alpine Ski Racing: Basis for Evaluating Physical Demands and Safety

PubMed Central

Gilgien, Matthias; Kröll, Josef; Spörri, Jörg; Crivelli, Philip; Müller, Erich

2018-01-01

External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG) and downhill (DH) are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC) alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS), for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS). Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski–snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski–snow friction) and air drag force were computed. This study showed that (1) the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2) physical demands were substantially different between GS, SG, and DH; and (3) safety-related reduction of skiing speed might be most effectively achieved by increasing the ski–snow friction force in GS and SG. For DH an increase in the ski–snow friction force might be equally as effective as an increase in air drag force. PMID:29559918

The skiers knee without swelling or instability, a difficult diagnosis: a case report

PubMed Central

O'Donnell, Mark E; Badger, Stephen A; Campbell, David; Loan, Willie; Sinnott, Brendan

2007-01-01

Skiing as a recreational activity has increased exponentially in the last twenty-years. Similar to any sporting activity, participants can sustain various types of injury, which provides the emergency departments with a continuous supply of patients. The injury pattern from the slopes has also changed over this time period, due to alterations and improvements in ski equipment. An increased diversity in alpine skiing techniques, as well as snowboarding and cross-terrain disciplines has also influenced this change. We present a multi-media experience of a high-speed ski fall that caused a valgus-external rotation injury to the right knee that precluded the patient from further ski activity. There was no bruising, swelling or instability demonstrated and the patient returned to ski activities 24-hours post-injury. Although this injury appeared clinically benign initially, the patient complained of persistent pain around the right knee which was causing occupational difficulties. Following normal clinical assessment, the patient returned to work but continued to complain of persistent pain at the lateral aspect of the right knee. Magnetic Resonance Imaging (MRI) demonstrated extensive bone marrow oedema (BMO), a mild depression of the articular cortex compression with a small focus of articular cartilage disruption and microfractures of the lateral tibial plateau. The patient was treated conservatively and remains well with avoidance of impact exercises 14-months post-injury. In the presence of any high speed injury, we would stress that regardless of initial normal investigations, clinical suspicion should remain paramount and not deter the physician from further investigation in the presence of continuing symptomatology. PMID:17448236

Sports injuries and illnesses during the Granada Winter Universiade 2015

PubMed Central

Gallo-Vallejo, Miguel Ángel; de la Cruz-Márquez, Juan Carlos; de la Cruz-Campos, Adrián; de la Cruz-Campos, Juan Carlos; Pestaña-Melero, Francisco Luis; Carmona-Ruiz, Ginés; Gallo-Galán, Luz María

2016-01-01

Objective To analyse the incidence of diseases and injuries suffered by athletes participating in the 27th Winter Sports Universiade held in Granada, Spain. Methods The daily occurrence of injuries and diseases was registered at the point of first aid (Borreguiles, 2665 metres above sea level (masl)) and in the clinic of Pradollano (2017 masl), both in Sierra Nevada, as well as in medical services provided by the organising committee of Granada 2015 Universiade and located in sport pavilions in which indoor competitions are held. Results A total of 1109 athletes (650 men, 58.61%; 459 women, 41.39%). Nine diseases and 68 injuries were recorded. In total, the rate of injury was 6.13% (7.07% for men and 4.79% for women). The percentage of injury was highest in alpine skiing (10.34%) followed by freestyle skiing (8.62%). In relation to the time of exposure, freestyle skiing showed the shortest time of exposure (0.31 hours) before suffering an injury. Short track speed skating showed the longest exposure (9.80 hours), before suffering an injury. The most common anatomical areas of injury were the head, shoulder and knee (13.23%). Only nine diseases were suffered (four women and five men) of which six were infections, one was a friction burn, one was a lipothymy and one a cluster headache due to height. Conclusion In general, 6.13% of the athletes sustained at least one injury and 0.81% a disease, which is a much lower percentage than that recorded in similar events. The incidence of injuries and diseases varied among sport specialities. PMID:28879023

Sports injuries and illnesses during the Granada Winter Universiade 2015.

PubMed

Gallo-Vallejo, Miguel Ángel; de la Cruz-Márquez, Juan Carlos; de la Cruz-Campos, Adrián; de la Cruz-Campos, Juan Carlos; Pestaña-Melero, Francisco Luis; Carmona-Ruiz, Ginés; Gallo-Galán, Luz María

2016-01-01

To analyse the incidence of diseases and injuries suffered by athletes participating in the 27th Winter Sports Universiade held in Granada, Spain. The daily occurrence of injuries and diseases was registered at the point of first aid (Borreguiles, 2665 metres above sea level (masl)) and in the clinic of Pradollano (2017 masl), both in Sierra Nevada, as well as in medical services provided by the organising committee of Granada 2015 Universiade and located in sport pavilions in which indoor competitions are held. A total of 1109 athletes (650 men, 58.61%; 459 women, 41.39%). Nine diseases and 68 injuries were recorded. In total, the rate of injury was 6.13% (7.07% for men and 4.79% for women). The percentage of injury was highest in alpine skiing (10.34%) followed by freestyle skiing (8.62%). In relation to the time of exposure, freestyle skiing showed the shortest time of exposure (0.31 hours) before suffering an injury. Short track speed skating showed the longest exposure (9.80 hours), before suffering an injury. The most common anatomical areas of injury were the head, shoulder and knee (13.23%). Only nine diseases were suffered (four women and five men) of which six were infections, one was a friction burn, one was a lipothymy and one a cluster headache due to height. In general, 6.13% of the athletes sustained at least one injury and 0.81% a disease, which is a much lower percentage than that recorded in similar events. The incidence of injuries and diseases varied among sport specialities.

Injuries and illnesses in a cohort of elite youth alpine ski racers and the influence of biological maturity and relative age: a two-season prospective study

PubMed Central

Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Oberhoffer, Renate; Raschner, Christian

2017-01-01

Background Studies on injuries and illnesses involving youth ski racers younger than 15 years are lacking in the literature. The aim of this study was prospectively to assess the incidence, prevalence, and severity of traumatic and overuse injuries, as well as illnesses of elite youth ski racers with regard to sex, biological maturity status, and relative age. Subjects and methods A prospective, longitudinal cohort design was used to monitor the anthropometrics, training characteristics, traumatic and overuse injuries, and illnesses of 82 elite youth ski racers (51 males, 31 females, age 9–14 years) over 2 consecutive years. The exact training exposure (skiing and athletic) was recorded. Relative age and estimated biological maturity status were assessed. Results Relatively low injury incidence or prevalence (traumatic, 0.86/1,000 hours of training; overuse, 0.28/1,000 hours) and comparably high illness prevalence (2.4/athlete) were reported. The knee was the most commonly affected body part (traumatic injuries 36.5%, overuse injuries 82%). A high number of bone fractures were revealed (46%), while no stress fractures occurred; 66% of the illnesses were respiratory tract infections. No differences were found between males and females, the differing maturity groups, or relative age quartiles. Early-maturing athletes had comparably low traumatic and overuse-injury rates. Relatively younger athletes had low traumatic injury rates. Conclusion The injury-prevention measures implemented in the training process of youth ski racers seem to contribute to a low incidence of injury. Biological maturity status should be considered in the training process to prevent injuries in late-maturing athletes. PMID:28546774

Sustainability of the Dissemination of an Occupational Sun Protection Program in a Randomized Trial

PubMed Central

Buller, David B.; Walkosz, Barbara J.; Andersen, Peter A.; Scott, Michael D.; Dignan, Mark B.; Cutter, Gary R.; Zhang, Xiao; Kane, Ilima L.

2012-01-01

The sustainability of an occupational sun safety program, Go Sun Smart (GSS), was explored in a randomized trial, testing dissemination strategies at 68 U.S. and Canadian ski areas in 2004-2007. All ski areas received GSS from the National Ski Areas Association through a Basic Dissemination Strategy (BDS) using conference presentations and free materials. Half of the ski areas were randomly assigned to a theory-based Enhanced Dissemination Strategy (EDS) with personal contact supporting GSS use. Use of GSS was assessed at immediate and long-term follow-up posttests by on-site observation. Use of GSS declined from the immediate (M=5.72) to the long-term follow-up (M=6.24), F[1,62]=6.95, p=.01, but EDS ski areas (M=6.53) continued to use GSS more than BDS ski areas (M=4.49), F(1,62)=5.75, p=0.02, regardless of observation, F(1,60)=0.05, p=.83. Despite declines over time, a group of ski areas had sustained high program use and active dissemination methods had sustained positive effects on GSS implementation. PMID:22102323

Dissemination of go sun smart in outdoor recreation: effect of program exposure on sun protection of guests at high-altitude ski areas.

PubMed

Walkosz, Barbara J; Buller, David B; Andersen, Peter A; Scott, Michael D; Dignan, Mark B; Cutter, Gary R; Liu, Xia; Maloy, Julie A

2014-09-01

Go Sun Smart is a theory-based health communication program designed to influence sun-protection behaviors of employees and guests at high-altitude ski areas to reduce skin cancer risk. The effects of Go Sun Smart, in a Phase IV dissemination randomized posttest-only trial, on sun-protection behaviors of ski area guests are reported. Program use was assessed by on-site observation and guest message exposure, and sun protection was measured in intercept surveys at ski areas. Dissemination strategy-enhanced versus basic-was not significantly related to sun safety practices. Additional analyses examined the relation between message exposure and guests' sun safety practices. Ski areas displaying at least 6 Go Sun Smart materials in guest-only areas and 9 Go Sun Smart materials throughout the area increased guests' message exposure. Higher message exposure within the high-use ski areas was associated with improved sun protection by guests but not within the low-use ski areas. The authors underscore the importance of program implementation and message exposure on the success of evidence-based health communication efforts applied industrywide.

Collecting Kinematic Data on a Ski Track with Optoelectronic Stereophotogrammetry: A Methodological Study Assessing the Feasibility of Bringing the Biomechanics Lab to the Field.

PubMed

Spörri, Jörg; Schiefermüller, Christian; Müller, Erich

2016-01-01

In the laboratory, optoelectronic stereophotogrammetry is one of the most commonly used motion capture systems; particularly, when position- or orientation-related analyses of human movements are intended. However, for many applied research questions, field experiments are indispensable, and it is not a priori clear whether optoelectronic stereophotogrammetric systems can be expected to perform similarly to in-lab experiments. This study aimed to assess the instrumental errors of kinematic data collected on a ski track using optoelectronic stereophotogrammetry, and to investigate the magnitudes of additional skiing-specific errors and soft tissue/suit artifacts. During a field experiment, the kinematic data of different static and dynamic tasks were captured by the use of 24 infrared-cameras. The distances between three passive markers attached to a rigid bar were stereophotogrammetrically reconstructed and, subsequently, were compared to the manufacturer-specified exact values. While at rest or skiing at low speed, the optoelectronic stereophotogrammetric system's accuracy and precision for determining inter-marker distances were found to be comparable to those known for in-lab experiments (< 1 mm). However, when measuring a skier's kinematics under "typical" skiing conditions (i.e., high speeds, inclined/angulated postures and moderate snow spraying), additional errors were found to occur for distances between equipment-fixed markers (total measurement errors: 2.3 ± 2.2 mm). Moreover, for distances between skin-fixed markers, such as the anterior hip markers, additional artifacts were observed (total measurement errors: 8.3 ± 7.1 mm). In summary, these values can be considered sufficient for the detection of meaningful position- or orientation-related differences in alpine skiing. However, it must be emphasized that the use of optoelectronic stereophotogrammetry on a ski track is seriously constrained by limited practical usability, small-sized capture volumes and the occurrence of extensive snow spraying (which results in marker obscuration). The latter limitation possibly might be overcome by the use of more sophisticated cluster-based marker sets.

A Coupled Snow Operations-Skier Demand Model for the Ontario (Canada) Ski Region

NASA Astrophysics Data System (ADS)

Pons, Marc; Scott, Daniel; Steiger, Robert; Rutty, Michelle; Johnson, Peter; Vilella, Marc

2016-04-01

The multi-billion dollar global ski industry is one of the tourism subsectors most directly impacted by climate variability and change. In the decades ahead, the scholarly literature consistently projects decreased reliability of natural snow cover, shortened and more variable ski seasons, as well as increased reliance on snowmaking with associated increases in operational costs. In order to develop the coupled snow, ski operations and demand model for the Ontario ski region (which represents approximately 18% of Canada's ski market), the research utilized multiple methods, including: a in situ survey of over 2400 skiers, daily operations data from ski resorts over the last 10 years, climate station data (1981-2013), climate change scenario ensemble (AR5 - RCP 8.5), an updated SkiSim model (building on Scott et al. 2003; Steiger 2010), and an agent-based model (building on Pons et al. 2014). Daily snow and ski operations for all ski areas in southern Ontario were modeled with the updated SkiSim model, which utilized current differential snowmaking capacity of individual resorts, as determined from daily ski area operations data. Snowmaking capacities and decision rules were informed by interviews with ski area managers and daily operations data. Model outputs were validated with local climate station and ski operations data. The coupled SkiSim-ABM model was run with historical weather data for seasons representative of an average winter for the 1981-2010 period, as well as an anomalously cold winter (2012-13) and the record warm winter in the region (2011-12). The impact on total skier visits and revenues, and the geographic and temporal distribution of skier visits were compared. The implications of further climate adaptation (i.e., improving the snowmaking capacity of all ski areas to the level of leading resorts in the region) were also explored. This research advances system modelling, especially improving the integration of snow and ski operations models with demand and socioeconomic implications. This innovative integrated systems model approach can be exported to other major ski tourism markets (e.g., Canada, USA, Western and Eastern Europe, Australia, Japan) to facilitate global comparative assessments of ski tourism vulnerability to climate change, establishing the standard for ski tourism vulnerability assessments and advancing scholarly work on sustainable tourism and climate-compatible development in mountain communities.

Impact assessment of proposed ski areas: A GIS approach integrating biological, physical and landscape indicators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geneletti, Davide

Ski centres are characterized by significant environmental impacts that occur during both the construction and the operation phase. In Trentino, a well-known ski destination located in northern Italy, new ski areas were identified by planning tools without conducting a formal assessment of their effects on the environment. This paper presents a study to assess and compare the impacts of the proposed ski areas within two valleys strongly linked to winter tourism: the Fiemme and Fassa Valleys. The method is based on the computation of spatial indicators using a Geographical Information System (GIS) to predict and quantify critical impacts, such asmore » ecosystem loss and fragmentation, soil erosion, geomorphologic hazards, interference with flora and fauna, and visibility. Subsequently, multicriteria analysis was applied to generate composite indices, and to rank ski areas according to their overall suitability. Finally, sensitivity analyses allowed to test the stability of the results. The study concluded that two of the proposed ski areas are located in highly unsuitable environment, and the relevant plan provisions should be revised.« less

A national strategy for a long-term monitoring of permafrost and periglacial processes and their relationship to natural hazard prevention in Austria

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas; Bartsch, Annett; Gitschthaler, Christoph; Reisenhofer, Stefan; Weyss, Gernot; Riedl, Claudia; Avian, Michael

2016-04-01

About 2.5% (~2000 km²) of the national territory of Austria is influenced by permafrost conditions. A slightly smaller area of Austria is additionally affected by deep seasonal frost which is, however, similarly exposed to intensive physical weathering and related geomorphic processes. Currently, 23 skiing resorts, 31 water reservoirs and 42 mountain huts are either directly or indirectly influenced by permafrost and associated processes in Austria as determined from regional permafrost models. Ground thermal changes most likely affect the ground stability and infrastructure in those areas. Therefore, changes in the distribution and characteristics of permafrost and seasonal frost are of high economic and ecological importance. A range of Austrian institutions are interested in systematic permafrost monitoring (several universities, geological surveys, the Austrian torrent and avalanche control agency or several different alpine clubs). However, to date no coordinated monitoring network has been established on a national scale and a strategy for long-term permafrost/periglacial observation did not exist so far. Such a national strategy has been developed in 2015 within the permAT project funded through the StartClim2014-program. During permAT an extensive literature review and data search as well as a workshop with 40 participants (scientists, stakeholder and policy maker) were accomplished. The workshop allowed the integration of national as well as international colleagues into the strategy development. Results of permAT clearly demonstrate that the number of present permafrost/periglacial monitoring sites is far too little in Austria. Only few alpine areas of Austria are well represented by the existing monitoring activities but large areas lack such instrumentations. Furthermore, permafrost boreholes exist at only three sites in central Austria (all contribution to the GTN-P network) and there is a lack of knowledge about thermal conditions and recent changes of permafrost temperatures in western Austria. A central recommendation of the permAT-strategy is to increase the number of monitoring sites based on our analyses of the current situation and exchanges with different stakeholders. This should include temperature measurements in deep and shallow boreholes close to the surface, geophysical surveys and ground movement measurements (rock glaciers, instable rock faces). In addition to the terrestrial measurements a spatially continuous observation of surface movements with remote sensing methods is required. Demand is highest for the entire federal province of Tyrol, the district of Zell am See (province of Salzburg) and the south-eastern part of the province of Vorarlberg. In order to achieve a similar spatial coverage and technical set-up as in Switzerland a minimum investment of 1.5 Mio € is required taking advantages in synergies with e.g. existing automatic weather stations (e.g. from the Central Institute for Meteorology and Geodynamics), alpine huts and skiing infrastructure into account. Financial support could - similarly to Switzerland - come from a combination of partners from public institutions, economy and research institutes.

Modelling UV irradiances on arbitrarily oriented surfaces: effects of sky obstructions

NASA Astrophysics Data System (ADS)

Hess, M.; Koepke, P.

2008-02-01

A method is presented to calculate UV irradiances on inclined surfaces that additionally takes into account the influence of sky obstructions caused by obstacles such as mountains, houses, trees, or umbrellas. Thus the method allows calculating the impact of UV radiation on biological systems, such as for instance the human skin or eye, in any natural or artificial environment. The method, a combination of radiation models, is explained and the correctness of its results is demonstrated. The effect of a natural skyline is shown for an Alpine ski area, where the UV irradiance even on a horizontal surface may increase due to reflection at snow by more than 10%. In contrast in a street canyon the irradiance on a horizontal surface is reduced down to 30% in shadow and to about 75% for a position in the sun.

78 FR 60816 - Proposed Directive for Additional Seasonal or Year-Round Recreation Activities at Ski Areas

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-02

... Authorized Officers to ensure that ski area operations comply with Forest Service regulations and permit... significant modifications to topography to facilitate construction or operations. The Agency is also proposing... in the ski area's master development plan; (2) Not compromise snow sports operations or functions...

High incidence of injury at the Sochi 2014 Winter Paralympic Games: a prospective cohort study of 6564 athlete days.

PubMed

Derman, W; Schwellnus, M P; Jordaan, E; Runciman, P; Van de Vliet, P; Blauwet, C; Webborn, N; Willick, S; Stomphorst, J

2016-09-01

To describe the epidemiology of injuries at the Sochi 2014 Winter Paralympic Games. A total of 547 athletes from 45 countries were monitored daily for 12 days during the Sochi 2014 Winter Paralympic Games (6564 athlete days). Daily injury data were obtained from teams with their own medical support (32 teams, 510 athletes) and teams without their own medical support (13 teams, 37 athletes) through electronic data capturing systems. There were 174 total injuries reported, with an injury incidence rate (IR) of 26.5 per 1000 athlete days (95% CI 22.7% to 30.8%). There was a significantly higher IR recorded in alpine skiing/snowboarding (IR of 41.1 (95% CI 33.7% to 49.6%) p=0.0001) compared to cross-country skiing/biathlon, ice sledge hockey or wheelchair curling. Injuries in the shoulder region were the highest single-joint IR (IR of 6.4 (95% CI 4.6% to 8.6%)), although total upper and lower body IR were similar (IR 8.5 vs 8.4 (95% CI 6.4% to 11.1%)). Furthermore, the IR of acute injuries was significantly higher than other types of injury onset (IR of 17.8 (95% CI 14.7% to 21.4%)). In a Winter Paralympic Games setting, athletes report higher injury incidence than do Olympic athletes or athletes in a Summer Paralympic Games setting. The highest incidence of injury was reported in the alpine skiing/snowboarding sporting category. There was a similar incidence of injury in the upper and lower limbs. The joint with the greatest rate of injury reported was the shoulder joint. Our data can inform injury prevention programmes and policy considerations regarding athlete safety in future Winter Paralympic Games. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Modelling technical snow production for skiing areas in the Austrian Alps with the physically based snow model AMUNDSEN

NASA Astrophysics Data System (ADS)

Hanzer, F.; Marke, T.; Steiger, R.; Strasser, U.

2012-04-01

Tourism and particularly winter tourism is a key factor for the Austrian economy. Judging from currently available climate simulations, the Austrian Alps show a particularly high vulnerability to climatic changes. To reduce the exposure of ski areas towards changes in natural snow conditions as well as to generally enhance snow conditions at skiing sites, technical snowmaking is widely utilized across Austrian ski areas. While such measures result in better snow conditions at the skiing sites and are important for the local skiing industry, its economic efficiency has also to be taken into account. The current work emerges from the project CC-Snow II, where improved future climate scenario simulations are used to determine future natural and artificial snow conditions and their effects on tourism and economy in the Austrian Alps. In a first step, a simple technical snowmaking approach is incorporated into the process based snow model AMUNDSEN, which operates at a spatial resolution of 10-50 m and a temporal resolution of 1-3 hours. Locations of skiing slopes within a ski area in Styria, Austria, were digitized and imported into the model environment. During a predefined time frame in the beginning of the ski season, the model produces a maximum possible amount of technical snow and distributes the associated snow on the slopes, whereas afterwards, until to the end of the ski season, the model tries to maintain a certain snow depth threshold value on the slopes. Due to only few required input parameters, this approach is easily transferable to other ski areas. In our poster contribution, we present first results of this snowmaking approach and give an overview of the data and methodology applied. In a further step in CC-Snow, this simple bulk approach will be extended to consider actual snow cannon locations and technical specifications, which will allow a more detailed description of technical snow production as well as cannon-based recordings of water and energy consumption.

Sustainability of the Dissemination of an Occupational Sun Protection Program in a Randomized Trial

ERIC Educational Resources Information Center

Buller, David B.; Walkosz, Barbara J.; Andersen, Peter A.; Scott, Michael D.; Dignan, Mark B.; Cutter, Gary R.; Zhang, Xiao; Kane, Ilima L.

2012-01-01

Sustainability of an occupational sun safety program, Go Sun Smart (GSS), was explored in a randomized trial, testing dissemination strategies at 68 U.S. and Canadian ski areas in 2004-2007. All ski areas received GSS from the National Ski Areas Association through a Basic Dissemination Strategy (BDS) using conference presentations and free…

Crossing physical simulations of snow conditions and a geographic model of ski area to assess ski resorts vulnerability

NASA Astrophysics Data System (ADS)

François, Hugues; Spandre, Pierre; Morin, Samuel; George-Marcelpoil, Emmanuelle; Lafaysse, Matthieu; Lejeune, Yves

2016-04-01

In order to face climate change, meteorological variability and the recurrent lack of natural snow on the ground, ski resorts adaptation often rely on technical responses. Indeed, since the occurrence of episodes with insufficient snowfalls in the early 1990's, snowmaking has become an ordinary practice of snow management, comparable to grooming, and contributes to optimise the operation of ski resorts. It also participates to the growth of investments and is associated with significant operating costs, and thus represents a new source of vulnerability. The assessment of the actual effects of snowmaking and of snow management practices in general is a real concern for the future of the ski industry. The principal model use to simulate snow conditions in resorts, Ski Sim, has also been moving this way. Its developers introduced an artificial input of snow on ski area to complete natural snowfalls and considered different organisations of ski lifts (lower and upper zones). However the use of a degree-day model prevents them to consider the specific properties of artificial snow and the impact of grooming on the snowpack. A first proof of concept in the French Alps has shown the feasibility and the interest to cross the geographic model of ski areas and the output of the physically-based reanalysis of snow conditions SAFRAN - Crocus (François et al., CRST 2014). Since these initial developments, several ways have been explored to refine our model. A new model of ski areas has been developed. Our representation is now based on gravity derived from a DEM and ski lift localisation. A survey about snow management practices also allowed us to define criteria in order to model snowmaking areas given ski areas properties and tourism infrastructures localisation. We also suggest to revisit the assessment of ski resort viability based on the "one hundred days rule" based on natural snow depth only. Indeed, the impact of snow management must be considered so as to propose reliability indices that are both physically and socio-economically meaningful. Our contribution proposes to present these works in the context of a test resort in the French Alps and its snow conditions during the period 2000-2012. In order to show the impact of different management practices three configurations are considered: natural snowfalls, groomed natural snowfalls and managed snow (natural and artificial snowpack combined with grooming) and discuss the implications of the results in terms of the assessment of the climate vulnerability of ski resorts.

Surface erosion at disturbed alpine sites: effects of vegetation cover and plant diversity

NASA Astrophysics Data System (ADS)

Martin, C.; Pohl, M.; Alewell, C.; Körner, C.; Buttler, A.; Rixen, C.

2009-04-01

The relationship between plant diversity and soil stability in disturbed alpine terrain is poorly studied. In this paper, we investigated the influence of plant cover and diversity on water run-off and sediment yield on ski slopes. Rainfall simulations were conducted on a micro-scale (25 x 25 cm) to be able to replicate plots with different degrees of vegetation cover. We selected plots with 10%, 30% and 60% of vegetation cover containing different combinations of plant diversities: (i) grass, (ii) herb, (iii) moss/ lichen, and all combinations of these plant groups. Each combination was replicated five times with an applied rain intensity of 375 ml min-1 for about 5 minutes. As could be expected, percent vegetation cover had a large effect on surface erosion: sediment yield decreased with increasing vegetation cover. However, within the plots with 60% cover, sediment yield was lower at higher plant diversity and functional group diversity. The findings of this study support the view that beside the re-establishment of a closed vegetation cover, plant diversity is a relevant factor to reduce surface erosion at disturbed sites in alpine ecosystems.

Mid-Mountain Clouds at Whistler During the Vancouver 2010 Winter Olympics and Paralympics

NASA Astrophysics Data System (ADS)

Mo, Ruping; Joe, Paul; Isaac, George A.; Gultepe, Ismail; Rasmussen, Roy; Milbrandt, Jason; McTaggart-Cowan, Ron; Mailhot, Jocelyn; Brugman, Melinda; Smith, Trevor; Scott, Bill

2014-01-01

A comprehensive study of mid-mountain clouds and their impacts on the Vancouver 2010 Winter Olympics and Paralympics is presented. Mid-mountain clouds were frequently present on the Whistler alpine venue, as identified in an extensive archive of webcam images over a 45-day period from February 5 to March 21, 2010. These clouds posed serious forecast challenges and had significant impacts on some Olympic and Paralympic alpine skiing competitions. Under fair weather conditions, a diurnal upslope (anabatic) flow can work in concert with a diurnal temperature inversion aloft to produce a localized phenomenon known as "Harvey's Cloud" at Whistler. Two detailed case studies in this paper suggest that mid-mountain clouds can also develop in the area as a result of a moist valley flow interacting with a downslope flow descending from the mountaintop. A southerly inflow through the Sea-to-Sky corridor can be channeled by the local topography into a westerly upslope flow toward Whistler Mountain, resulting in orographic clouds on the alpine venue. Under favorable circumstances, these clouds are trapped to the mid-mountain zone by the leeward subsidence of an elevated southerly flow. The presence of the downslope subsidence was manifested by a distinguished dry layer observed on the top of the mid-mountain clouds in both cases. It is the subsidence-induced adiabatic warming that imposes a strong buoyant suppression to trap the mid-mountain cloud. On the other hand, the subsidence-induced dry layer has the potential to trigger evaporative instability to periodically breakup the mid-mountain cloud.

Collecting Kinematic Data on a Ski Track with Optoelectronic Stereophotogrammetry: A Methodological Study Assessing the Feasibility of Bringing the Biomechanics Lab to the Field

PubMed Central

Müller, Erich

2016-01-01

In the laboratory, optoelectronic stereophotogrammetry is one of the most commonly used motion capture systems; particularly, when position- or orientation-related analyses of human movements are intended. However, for many applied research questions, field experiments are indispensable, and it is not a priori clear whether optoelectronic stereophotogrammetric systems can be expected to perform similarly to in-lab experiments. This study aimed to assess the instrumental errors of kinematic data collected on a ski track using optoelectronic stereophotogrammetry, and to investigate the magnitudes of additional skiing-specific errors and soft tissue/suit artifacts. During a field experiment, the kinematic data of different static and dynamic tasks were captured by the use of 24 infrared-cameras. The distances between three passive markers attached to a rigid bar were stereophotogrammetrically reconstructed and, subsequently, were compared to the manufacturer-specified exact values. While at rest or skiing at low speed, the optoelectronic stereophotogrammetric system’s accuracy and precision for determining inter-marker distances were found to be comparable to those known for in-lab experiments (< 1 mm). However, when measuring a skier’s kinematics under “typical” skiing conditions (i.e., high speeds, inclined/angulated postures and moderate snow spraying), additional errors were found to occur for distances between equipment-fixed markers (total measurement errors: 2.3 ± 2.2 mm). Moreover, for distances between skin-fixed markers, such as the anterior hip markers, additional artifacts were observed (total measurement errors: 8.3 ± 7.1 mm). In summary, these values can be considered sufficient for the detection of meaningful position- or orientation-related differences in alpine skiing. However, it must be emphasized that the use of optoelectronic stereophotogrammetry on a ski track is seriously constrained by limited practical usability, small-sized capture volumes and the occurrence of extensive snow spraying (which results in marker obscuration). The latter limitation possibly might be overcome by the use of more sophisticated cluster-based marker sets. PMID:27560498

Alpine Soils as long-term Bioindicators

NASA Astrophysics Data System (ADS)

Nestroy, O.

2009-04-01

Alpine soils as long-term bioindicators The introductory words concern the definitions and peculiarities of alpine soils and their position in the Austrian Soil Classification 2000 in comparison with the World Reference Base for Soil Resources 2006. The important parameters for genesis and threats for these soils in steep and high positions are discussed. It must be emphasized that the main threats are the very different kinds of erosion e.g. by water, wind and snow, and also by skiing (end of season) as well as and mountain-biking (mainly summer-sport). Due the very slow regeneration and - in this connection - due to the very slow changes of the soil entities, these soils give an utmost importance as a long-time bioindicator. With regard to the climate change one can assume an increase in the content of organic matter on site, but also an increase of erosion and mass movement on the other site, e. g. in kind of "plaiken" (soil slide) as result of an increasing intensity of rainfall. It lies partly in our hands to diminish the number and the intensity of the threats, we can influence the soil development, but the result to reach a new ecological equilibrium is very long - in case of alpine soil more than two generations.

Medical Care Before and During the Winter Paralympic Games in Turin 2006, Vancouver 2010 and Sochi 2014.

PubMed

Gawroński, Wojciech; Sobiecka, Joanna

2015-11-22

Medical care in disabled sports is crucial both as prophylaxis and as ongoing medical intervention. The aim of this paper was to present changes in the quality of medical care over the consecutive Paralympic Games (PG). The study encompassed 31 paralympians: Turin (11), Vancouver (12), and Sochi (8) competing in cross-country skiing, alpine skiing, biathlon and snowboarding. The first, questionnaire-based, part of the study was conducted in Poland before the PG. The athletes assessed the quality of care provided by physicians, physiologists, dieticians, and physiotherapists, as well as their cooperation with the massage therapist and the psychologist. The other part of the study concerned the athletes' health before leaving for the PG, as well as their diseases and injuries during the PG. The quality of medical care was poor before the 2006 PG, but satisfactory before the subsequent PG. Only few athletes made use of psychological support, assessing it as poor before the 2006 PG and satisfactory before the 2010 and 2014 PG. The athletes' health condition was good during all PG. The health status of cross-country skiers was confirmed by a medical fitness certificate before all PG, while that of alpine skiers only before the 2014 PG. There were no serious diseases; training injuries precluded two athletes from participation. The quality of medical care before the PG was poor, however, became satisfactory during the actual PG. The resulting ad hoc pattern deviates from the accepted standards in medical care in disabled sports.

Modelling UV irradiances on arbitrarily oriented surfaces: effects of sky obstructions

NASA Astrophysics Data System (ADS)

Hess, M.; Koepke, P.

2008-07-01

A method is presented to calculate UV irradiances on inclined surfaces that additionally takes into account the influence of sky obstructions caused by obstacles such as mountains, houses, trees, or umbrellas. With this method it is thus possible to calculate the impact of UV radiation on biological systems, such as, for instance, the human skin or eye, in any natural or artificial environment. The method, which consists of a combination of radiation models, is explained here and the accuracy of its results is demonstrated. The effect of a natural skyline is shown for an Alpine ski area, where the UV irradiance even on a horizontal surface may increase due to reflection from snow by more than 10 percent. In contrast, in a street canyon the irradiance on a horizontal surface is reduced to 30% in shadow and to about 75% for a position in the sun.

Reconstruction of head impacts in FIS World Cup alpine skiing.

PubMed

Steenstrup, Sophie Elspeth; Mok, Kam-Ming; McIntosh, Andrew S; Bahr, Roald; Krosshaug, Tron

2018-06-01

Prior to the 2013/2014 season, the International Ski Federation (FIS) increased the helmet testing speed from 5.4 to 6.8 m/s for alpine downhill, super-G and giant slalom. Whether this increased testing speed reflects head impact velocities in real head injury situations on snow is unclear. We therefore investigated the injury mechanisms and gross head impact biomechanics in seven real head injury situations among World Cup (WC) alpine skiers. We analysed nine head impacts from seven head injury videos from the FIS Injury Surveillance System, throughout nine WC seasons (2006-2015) in detail. We used commercial video-based motion analysis software to estimate head impact kinematics in two dimensions, including directly preimpact and postimpact, from broadcast video. The sagittal plane angular movement of the head was also measured using angle measurement software. In seven of nine head impacts, the estimated normal to slope preimpact velocity was higher than the current FIS helmet rule of 6.8 m/s (mean 8.1 (±SD 0.6) m/s, range 1.9±0.8 to 12.1±0.4 m/s). The nine head impacts had a mean normal to slope velocity change of 9.3±1.0 m/s, range 5.2±1.1 to 13.5±1.3 m/s. There was a large change in sagittal plane angular velocity (mean 43.3±2.9 rad/s (range 21.2±1.5 to 64.2±3.0 rad/s)) during impact. The estimated normal to slope preimpact velocity was higher than the current FIS helmet rule of 6.8 m/s in seven of nine head impacts. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Wetlands and ski resorts in the French Alps: main issues and innovative ideas for the preservation of wetlands in ski areas

NASA Astrophysics Data System (ADS)

Gaucherand, S.; Evette, A.; François, H.; Paccard, P.; Perretier, C.; Wlerick, L.

2009-04-01

This presentation is a synthesis of a symposium held last October in Cemagref, Grenoble with contributions from scientists as well as lift operators, NGO's, and administrations. In the context of global change, ski resorts must rethink their development models. The diversification of the touristic offer is encouraged and the specificity of the mountain territory is at the heart of a sustainable development. In this context, the preservation of interesting and fragile habitats such as wetlands is topical. Wetlands have many recognized functions: flooding reduction, water remediation, fertilization, biodiversity conservation… In mountain areas, wetlands are small and scattered. They are of special interest in particular for their role in biodiversity conservation and for their cultural and recreational benefits. However, in ski areas, wetlands can interact with the ski activity. Indeed, wetlands can speed up snow melting in spring and they often occupy ledges, which are strategic positions for the establishment of ski resort's facilities. The development of ski resorts can lead to the destruction or the deterioration of wetlands because of hydrologic interferences, fill in, pollution, etc. However, a few judicious steps can be taken to reduce or suppress these negative effects. In the Alps, geographical and administrative tools have been developed to help the decisions of ski-resort's administrators. Meetings between lift-operators, administrators of protected areas scientists and NGO's have also proved efficient when done at an early stage of a project, as shown by the example of the ski-resort "Les Saisies".

Go Sun Smart

ERIC Educational Resources Information Center

Scott, Michael D.; Buller, David B.; Walkosz, Barbara J.; Andersen, Peter A.; Cutter, Gary R.; Dignan, Mark B.

2008-01-01

This is the story of Go Sun Smart, a worksite wellness program endorsed by the North American Ski Area Association and funded by the National Cancer Institute. Between 2000 and 2002 we designed and implemented a large-scale worksite intervention at over 300 ski resorts in North America with the objective of reducing ski area employees and guests…

The use of computer graphics in the visual analysis of the proposed Sunshine Ski Area expansion

Treesearch

Mark Angelo

1979-01-01

This paper describes the use of computer graphics in designing part of the Sunshine Ski Area in Banff National Park. The program used was capable of generating perspective landscape drawings from a number of different viewpoints. This allowed managers to predict, and subsequently reduce, the adverse visual impacts of ski-run development. Computer graphics have proven,...

Translation of a Ski School Sun Safety Program to North American Ski and Snowboard Schools.

PubMed

Walkosz, Barbara J; Buller, David B; Andersen, Peter A; Scott, M D; Liu, X; Cutter, G R; Dignan, M B

2015-07-01

Health promotion programs that develop and implement strategies to promote sun safety practices to children have the potential to reduce skin cancer occurrence later in life. Go Sun Smart (GSS), a sun safety program for employees and guests of ski areas, was distributed to determine if an enhanced dissemination strategy was more effective than a basic dissemination strategy at reaching parents at ski and snowboard schools. On-site observations of GSS use and surveys of 909 parents/caregivers with children enrolled in ski and snowboard schools at 63 ski areas were conducted and analyzed using techniques for clustered designs. No differences were identified by dissemination strategy. Greater implementation of GSS (>5 messages posted) was associated with greater parental recall, 36.6% versus 16.7%, of materials, but not greater sun protection practices. Greater recall of messages, regardless of level of implementation, resulted in greater sun protection practices including applying sunscreen (p < .05), providing sunglasses and goggles (p < .01), and more use of all sun protection practices (p < .01). Ski areas with more program materials appeared to reach parents with sun safety advice and thus convinced them to take more precautions for their children. Sun safety need not be at odds with children's outdoor recreation activities. © 2015 Society for Public Health Education.

Medical Care Before and During the Winter Paralympic Games in Turin 2006, Vancouver 2010 and Sochi 2014

PubMed Central

Gawroński, Wojciech; Sobiecka, Joanna

2015-01-01

Medical care in disabled sports is crucial both as prophylaxis and as ongoing medical intervention. The aim of this paper was to present changes in the quality of medical care over the consecutive Paralympic Games (PG). The study encompassed 31 paralympians: Turin (11), Vancouver (12), and Sochi (8) competing in cross-country skiing, alpine skiing, biathlon and snowboarding. The first, questionnaire-based, part of the study was conducted in Poland before the PG. The athletes assessed the quality of care provided by physicians, physiologists, dieticians, and physiotherapists, as well as their cooperation with the massage therapist and the psychologist. The other part of the study concerned the athletes’ health before leaving for the PG, as well as their diseases and injuries during the PG. The quality of medical care was poor before the 2006 PG, but satisfactory before the subsequent PG. Only few athletes made use of psychological support, assessing it as poor before the 2006 PG and satisfactory before the 2010 and 2014 PG. The athletes’ health condition was good during all PG. The health status of cross-country skiers was confirmed by a medical fitness certificate before all PG, while that of alpine skiers only before the 2014 PG. There were no serious diseases; training injuries precluded two athletes from participation. The quality of medical care before the PG was poor, however, became satisfactory during the actual PG. The resulting ad hoc pattern deviates from the accepted standards in medical care in disabled sports. PMID:26834868

Power variables and bilateral force differences during unloaded and loaded squat jumps in high performance alpine ski racers.

PubMed

Patterson, Carson; Raschner, Christian; Platzer, Hans-Peter

2009-05-01

The purpose of this paper was to investigate the power-load relationship and to compare power variables and bilateral force imbalances between sexes with squat jumps. Twenty men and 17 women, all members of the Austrian alpine ski team (junior and European Cup), performed unloaded and loaded (barbell loads equal to 25, 50, 75, and 100% body weight [BW]) squat jumps with free weights using a specially designed spotting system. Ground reaction force records from 2 force platforms were used to calculate relative average power (P), relative average power in the first 100 ms of the jump (P01), relative average power in the first 200 ms of the jump (P02), jump height, percentage of best jump height (%Jump), and maximal force difference between dominant and nondominant leg (Fmaxdiff). The men displayed significantly higher values at all loads for P and jump height (p < 0.05). No significant differences were found in P01. The men had significantly higher P02 at all loads except 75% BW). Maximum P was reached at light loads (men at 25% BW and women at 0% BW), and P decreased uniformly thereafter. Individual power-load curves show a deflection point. It is proposed that the load where the power-load deflection point occurs be used as the power training load and not the load at which maximum P is reached. It is also proposed that loads not be described in %1-repetition maximum (RM), but as %BW. This system can be used to safely assess and train power with loaded jumps and free weights.

A local scale assessment of the climate change sensitivity of snow in Pyrenean ski resorts

NASA Astrophysics Data System (ADS)

Pesado, Cristina; Pons, Marc; Vilella, Marc; López-Moreno, Juan Ignacio

2016-04-01

The Pyrenees host one of the largest ski area in Europe after the Alps that encompasses the mountain area of the south of France, the north of Spain and the small country of Andorra. In this region, winter tourism is one of the main source of income and driving force of local development on these mountain communities. However, this activity was identified as one of the most vulnerable to a future climate change due to the projected decrease of natural snow and snowmaking capacity. However, within the same ski resorts different areas showed to have a very different vulnerability within the same resort based on the geographic features of the area and the technical management of the slopes. Different areas inside a same ski resort could have very different vulnerability to future climate change based on aspect, steepness or elevation. Furthermore, the technical management of ski resorts, such as snowmaking and grooming were identified to have a significant impact on the response of the snowpack in a warmer climate. In this line, two different ski resorts were deeply analyzed taken into account both local geographical features as well as the effect of the technical management of the runs. Principal Component Analysis was used to classify the main areas of the resort based on the geographic features (elevation, aspect and steepness) and identify the main representative areas with different local features. Snow energy and mass balance was simulated in the different representative areas using the Cold Regions Hydrological Model (CRHM) assuming different magnitudes of climate warming (increases of 2°C and 4°C in the mean winter temperature) both in natural conditions and assuming technical management of the slopes. Theses first results showed the different sensitivity and vulnerability to climate changes based on the local geography of the resort and the management of the ski runs, showing the importance to include these variables when analyzing the local vulnerability of a ski resort and the potential adaptation measures in each particular case.

Alpine debris flows triggered by a 28 July 1999 thunderstorm in the central Front Range, Colorado

NASA Astrophysics Data System (ADS)

Godt, Jonathan W.; Coe, Jeffrey A.

2007-02-01

On 28 July 1999, about 480 alpine debris flows were triggered by an afternoon thunderstorm along the Continental Divide in Clear Creek and Summit counties in the central Front Range of Colorado. The thunderstorm produced about 43 mm of rain in 4 h, 35 mm of which fell in the first 2 h. Several debris flows triggered by the storm impacted Interstate Highway 70, U.S. Highway 6, and the Arapahoe Basin ski area. We mapped the debris flows from color aerial photography and inspected many of them in the field. Three processes initiated debris flows. The first process initiated 11% of the debris flows and involved the mobilization of shallow landslides in thick, often well vegetated, colluvium. The second process, which was responsible for 79% of the flows, was the transport of material eroded from steep unvegetated hillslopes via a system of coalescing rills. The third, which has been termed the "firehose effect," initiated 10% of the debris flows and occurred where overland flow became concentrated in steep bedrock channels and scoured debris from talus deposits and the heads of debris fans. These three processes initiated high on steep hillsides (> 30°) in catchments with small contributing areas (< 8000 m 2), however, shallow landslides occurred on slopes that were significantly less steep than either overland flow process. Based on field observations and examination of soils mapping of the northern part of the study area, we identified a relation between the degree of soil development and the process type that generated debris flows. In general, areas with greater soil development were less likely to generate runoff and therefore less likely to generate debris flows by the firehose effect or by rilling. The character of the surficial cover and the spatially variable hydrologic response to intense rainfall, rather than a threshold of contributing area and topographic slope, appears to control the initiation process in the high alpine of the Front Range. Because debris flows initiated by rilling and the firehose effect tend to increase in volume as they travel downslope, these debris flows are potentially more hazardous than those initiated by shallow landslides, which tend to deposit material along their paths.

Alpine debris flows triggered by a 28 July 1999 thunderstorm in the central Front Range, Colorado

USGS Publications Warehouse

Godt, J.W.; Coe, J.A.

2007-01-01

On 28 July 1999, about 480 alpine debris flows were triggered by an afternoon thunderstorm along the Continental Divide in Clear Creek and Summit counties in the central Front Range of Colorado. The thunderstorm produced about 43??mm of rain in 4??h, 35??mm of which fell in the first 2??h. Several debris flows triggered by the storm impacted Interstate Highway 70, U.S. Highway 6, and the Arapahoe Basin ski area. We mapped the debris flows from color aerial photography and inspected many of them in the field. Three processes initiated debris flows. The first process initiated 11% of the debris flows and involved the mobilization of shallow landslides in thick, often well vegetated, colluvium. The second process, which was responsible for 79% of the flows, was the transport of material eroded from steep unvegetated hillslopes via a system of coalescing rills. The third, which has been termed the "firehose effect," initiated 10% of the debris flows and occurred where overland flow became concentrated in steep bedrock channels and scoured debris from talus deposits and the heads of debris fans. These three processes initiated high on steep hillsides (> 30??) in catchments with small contributing areas (< 8000??m2), however, shallow landslides occurred on slopes that were significantly less steep than either overland flow process. Based on field observations and examination of soils mapping of the northern part of the study area, we identified a relation between the degree of soil development and the process type that generated debris flows. In general, areas with greater soil development were less likely to generate runoff and therefore less likely to generate debris flows by the firehose effect or by rilling. The character of the surficial cover and the spatially variable hydrologic response to intense rainfall, rather than a threshold of contributing area and topographic slope, appears to control the initiation process in the high alpine of the Front Range. Because debris flows initiated by rilling and the firehose effect tend to increase in volume as they travel downslope, these debris flows are potentially more hazardous than those initiated by shallow landslides, which tend to deposit material along their paths. ?? 2006 Elsevier B.V. All rights reserved.

Utah ski patrol: assessing training types and resources.

PubMed

Sagalyn, Emily B; McDevitt, Marion C; Ernst, Ryan

2014-12-01

Skiers and snowboarders incur a variety of injuries and medical emergencies each year at ski resorts. The ski patrol is primarily responsible for initial triage, assessment and stabilization of these problems. The purpose of this study was to subjectively evaluate the type of training, resources, and equipment available to local ski patrols within Utah. Ski patrol directors at ski resorts in Utah were asked to complete a voluntary computerized survey. Of the 14 ski areas in Utah, ski patrol directors representing 8 resorts responded. The majority of patrols in Utah use Outdoor Emergency Care (OEC) as their primary education and certification source. Most programs also include site-specific training in addition to basic certification. All responding resorts had basic first responder equipment, including splinting devices, basic airway management, and hemorrhage control. Six of 8 responding resorts had affiliated clinics, and all had access to aeromedical transport. All of the responding ski patrol directors believed the current training level was adequate. Utah area ski patrollers frequently see trauma-related injuries and have the resources to assess and provide initial immobilization techniques. Many resorts have affiliated clinics with advanced providers, and all have access to aeromedical support to rapidly transfer patients to trauma centers. Medical directors may be of use for training as well as developing extended scope of practice protocols for advanced airway use or medication administration. Patrols may benefit from additional resort-specific training that addresses other frequently seen injuries or illnesses. Copyright © 2014 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

SkiSim - A semi-distributed model to assess the impact of climate change on ski season length and snowmaking

NASA Astrophysics Data System (ADS)

Steiger, R.

2009-04-01

Winter tourism is highly sensitive to climate change. The altitudinally- dependent line of natural snow reliability (e.g. Abegg et al. 2007) is losing its relevance for skilift operators, as for example in Tyrol 70% of the ski slopes are already covered by technical snow production. Less snowfall at lower altitudes and rising temperatures increase the demand for technical snow. Simultaneously, periods cold enough for snowmaking will get shorter and less frequent. Studies incorporating snowmaking are still rare and there is need for an assessment of the suitability of snowmaking as a successful adaptation strategy. The aim of this study is to assess the development of ski season lengths and snowmaking requirements under different climate change scenarios for ski areas in North and South Tyrol. A semi-distributed ski season model "SkiSim" was developed based on the temperature-index snow model of Kleindienst (2000) and the ski season model of Scott et al. (2007). As input variables only daily minimum and maximum temperature and precipitation are needed. Additionally, measured snowfall and snow depth are used for the calibration of the snowfall temperature at each climate station. Further snow model parameters (e.g. degree-day factor, snow metamorphosis) were adopted from Kleindienst (2000) and tested at all stations. Snowmaking module parameters were derived from interviews with ski area managers based on the methodology of Scott et al. (2007). Daily data (1960-2100) of the high resolution climate model REMO (10x10km) was used to produce climate change scenarios for four time horizons (2020s, 2030s, 2050s, 2080s) under two emission scenarios (A1B and B1). The climate change signal for change in temperature, (in standard deviation of temperature, in precipitation and in dry and wet spells) was processed on climate station data by the LARS weather generator. In winter (DJF), the change signal for daily average temperature from the 2020s to 2080s compared to 1971-2000 is +1,4°C to +3,5°C in the B1 scenario, and from +1,2°C to 5,7°C in the A1B scenario. Precipitation change in the A1B scenario is between +5% and +10%, in B1 it is +5% to +20%. The synthetic daily data produced by LARS-WG is the input data for the ski season model. Temperature and precipitation are distributed for each 100m altitude band, ranging from the lowest to the highest point of the ski area. The ski season model produces results for the whole ski area and not just for one single point (e.g. the lowest point in a ski area). Thus it is possible to assess the impact of climate change on ski season length and snowmaking in much greater detail than in previous studies. Based on these results, the consequences for winter tourism destinations can be assessed. Following the methodology of Breiling et al. (1997, 2008), the contribution of winter tourism to the regional economy and the number employments in tourism serve as an indicator for the vulnerability of communities and regions to climate change. In total 120 ski areas in North and South Tyrol are investigated in the running project. Results of three ski areas, different in size and altitude, will be presented. Sources: Abegg, B., S. Agrawala, Crick, F., de Montfalcon, A. (2007): Climate change impacts and adaptation in winter tourism. In: S. Agrawala, Climate Change in the European Alps. Adapting Winter Tourism and Natural Hazards Management. Paris, OECD: 25-60. Breiling, M., Charamza, P., Skage, O. (1997): Klimasensibilität österreichischer Bezirke mit besonderer Berücksichtigung des Wintertourismus. Rapport 1,Department of Landscape Planning Alnarp, Swedish University of Agricultural Sciences. Breiling, M., Charamza, P.,Feilmayr, W. (2008): Klimasensibilität des Salzburger Wintertourismus nach Bezirken, TTL, TU Vienna. Kleindienst, H. (2000): Snow hydrological models as tools for snow cover assessment and water resources management, Bern. Phd. Scott, D., G. McBoyle, Minogue, A. (2007): Climate Change and Quebećs Ski Industry. In: Global Environmental Change 17, 181-190.

Demographics of alpine skiing and snowboarding injury: lessons for prevention programs.

PubMed Central

Macnab, A. J.; Cadman, R.

1996-01-01

OBJECTIVE: To establish the demographics of ski injury in relation to age, gender, and perceived cause during a representative season to identify potential injury prevention strategies. SETTING: Blackcomb Mountain, a world class ski resort in British Columbia, Canada. METHODS: Data were collected from the lift ticket records and from ski patrol injury reports for one season, November to May 1991-2. RESULTS: There were 720,066 skier and snowboarder day visits counted by the mountain's lift ticket records, with a total of 2,092 injury reports (incidence 2.91 per 1,000 day visits). Of those with significant injuries (those requiring physician care), 1,210 (58%) were male. The highest injury rate was among children (age 7-12) and teens (age 13-17) with incidences of 3.18 and 3.34 significant injuries per 1,000 skier days, respectively. Head and face injuries constituted 17% and 22% of injuries, respectively in these groups. Overall 22% of head and face injuries were severe enough to cause loss of consciousness or clinical signs of concussion. This was the body region injured most frequently in males. For females over 7 years of age, the knee was the most common site of injury. For youths, the incidence of injuries during school organized activities was 25% higher than during other outings. CONCLUSIONS: The vulnerability of school group participants suggests special education is warranted. The high incidence of head injuries, particularly among young males, needs to be addressed. In light of the high proportion of this group who already wear helmets, the role of helmets in both protection and possible causation of head injury needs objective research. Images PMID:9346110

Sports injuries and illnesses in the Lillehammer 2016 Youth Olympic Winter Games.

PubMed

Steffen, Kathrin; Moseid, Christine Holm; Engebretsen, Lars; Søberg, Pia K; Amundsen, Olav; Holm, Kristian; Moger, Thomas; Soligard, Torbjørn

2017-01-01

Injury and illness surveillance during high-level youth sports events is an important first step in health prevention and caretaking of the young elite athletes. To analyse injuries and illnesses that occurred during the 10 days 2nd Youth Olympic Winter Games (YOG), held in Lillehammer 2016. We recorded the daily occurrence (or non-occurrence) of injuries and illnesses through the reporting of (1) all National Olympic Committee (NOC) medical teams and (2) the polyclinic and medical venues by the Lillehammer Organising Committee (LYOCOG) medical staff. In total, 1083 athletes (48 double-starters), 46% (n=502) of them females, from 70 NOCs were registered in the study. NOCs and LYOCOG reported 108 injuries and 81 illnesses, equalling to 9.5 injuries and 7.2 illnesses per 100 athletes. The percentage of injured athletes was highest in the snowboard and ski slopestyle and cross disciplines, alpine skiing and skeleton, and lowest in the Nordic skiing disciplines. Approximately, two-thirds of the injuries (n=71, 65.7%) prevented the athlete from training or competition, while 10 injuries (9.3%) were registered with an estimated absence from sport for >7 days. The rate of illness was highest in curling and the Nordic skiing disciplines with most of them being respiratory tract infections (81.5%). Overall, 9% of the athletes incurred at least one injury during the games, and 7% an illness, which is similar to the first YOG in Innsbruck 2012 and slightly lower compared with previous Winter Olympic Games. The incidence of injuries and illnesses varied substantially between sports. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Translation of a Ski School Sun Safety Program to North American Ski and Snowboard Schools

PubMed Central

Walkosz, B.J.; Buller, D.B.; Andersen, P.A.; Scott, M.D.; Liu, X.; Cutter, G.R.; Dignan, M.B.

2015-01-01

Unprotected and excessive exposure to ultraviolet radiation is the primary risk factor for skin cancer. Promoting sun safety practices to children and adolescents who recreate outdoors has the potential to reduce skin cancer occurrence later in life. Go Sun Smart (GSS), a sun safety program for employees and guests of ski areas was distributed to determine if an enhanced disseminations strategy was more effective than a basic dissemination strategy at reaching parents at ski and snowboard schools. On-site observations of GSS use and surveys of 909 parents/caregivers with children enrolled in ski and snowboard schools were conducted and analyzed using techniques for clustered designs. No differences were identified by dissemination strategy. Greater implementation of GSS was associated with greater parental recall of materials but not greater sun protection practices. Greater recall of messages, regardless of level of implementation, resulted in greater sun protection practices for children. GSS effectiveness trial’s favorable findings may have been successfully translated to ski and snowboard school across the North American ski industry. Ski areas that used more of the program materials appeared to reach parents with sun safety advice and thus convinced them to take more precautions for their children. Sun safety need not be at odds with children’s outdoor recreation activities. PMID:25761916

Land degradation at the Stara Planina ski resort.

PubMed

Ristić, Ratko; Kašanin-Grubin, Milica; Radić, Boris; Nikić, Zoran; Vasiljević, Nevena

2012-03-01

The environmental impacts of ski resorts in the Balkan region are great and can lead to landscape degradation and loss of land functionality. In this study, we present an example of the negative effects of human activities at the Stara Planina ski resort in southeastern Serbia. The objective of this study is detailed analysis of the characteristics of environmental impacts at the Stara Planina. The management of the ski area and ski slope development caused severe degradation of topsoil and native vegetation. The morphological characteristics of the area, lithological properties of the exposed material and climate conditions resulted in various geomorphic impacts, including rills, deep gullies, solifluctions and debris from rock weathering. Significant changes in land usage altered hydrological conditions, resulting in more frequent torrential floods in the downstream sections of the Zubska River and increased the sediment yield. Environmental impacts were analyzed in the immediate and wider zones of the ski resort in accordance with the specific topography and visual exposure. The restoration and erosion control measures have stopped degradation processes and helped to rehabilitate the appearance and functions of the landscape. The results show the importance of considering lithological (the type and characteristics of minerals present) and hydrological (precipitation, water storage capacity of soil, runoff) factors under the conditions of significant changes in land usage. The results of this investigation can contribute to the improvement of planning processes and the implementation of development projects in ski areas.

Adventure and Extreme Sports.

PubMed

Gomez, Andrew Thomas; Rao, Ashwin

2016-03-01

Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Whole-body vibration exposure in sport: four relevant cases.

PubMed

Tarabini, Marco; Saggin, Bortolino; Scaccabarozzi, Diego

2015-01-01

This study investigates the whole-body vibration exposure in kite surfing, alpine skiing, snowboarding and cycling. The vibration exposure was experimentally evaluated following the ISO 2631 guidelines. Results evidenced that the most critical axis is the vertical one. The weighted vibration levels are always larger than 2.5 m/s(2) and the vibration dose values are larger than 25 m/s(1.75). The exposure limit values of the EU directive are reached after 8-37 min depending on the sport. The vibration magnitude is influenced by the athletes' speed, by their skill level and sometimes by the equipment. The large vibration values suggest that the practice of sport activities may be a confounding factor in the aetiology of vibration-related diseases. The vibration exposure in some sports is expected to be large, but has never been quantified in the literature. Results of experiments performed in cycling, alpine and water sports outlined vibration levels exceeding the EU standard limit values.

Impact of climate change on the operation of ski slopes in South Korea

NASA Astrophysics Data System (ADS)

Kim, S.; Park, J. H.; Lee, D. K.

2017-12-01

The purpose of this study is to predict changes in the operation of ski slopes due to climate change and offer meaningful implications that the ski industry can refer to when preparing to address climate change. All 17 ski resorts in South Korea were selected as study sites. To determine the weather and managerial conditions for the operation of ski slopes, interviews with operators and a review of past weather and operational conditions were conducted. To project future changes in the season of operation for ski slopes, future weather data for the 2030s, 2060s, and 2090s from RCP scenarios were adapted to the conditions for the operation of ski slopes.The study found that the artificial snowmaking begins when the temperature reaches -2 °C, the slope is opened 9 days after artificial snowmaking starts, and the slope is closed when the temperature reaches 0 °C. By applying future weather data to these conditions, it is estimated that the ski season will decrease in the future as follows: from around 130 days at present to around 120 days based on RCP 2.0 and RCP 6.0, around 130 days based on RCP 4.5, and 90 days based on RCP 8.5 in the areas where the average temperature of the ski season is below -2 °C; from around 120 days at present to around 120 days based on RCP 2.0 and 4.5, around 100-days based on RCP 6.0, and 60 days based on RCP 8.5 in the areas where the average temperature of the ski season is below 0 °C; from around 90 days at present to around 80 days based on RCP 2.0, around 90 days based on RCP 4.5, around 50 days based on RCP 6.0, and 10 days based on RCP 8.5 in the areas where the average temperature of the ski season is above 0 °C. In addition, it is also estimated that in the 2090s, 16 of 17 ski resorts can survive based on RCP 2.6 and RCP 4.5, 13 ski resorts can survive based on RCP 6.0, and none of the resorts can survive based on RCP 8.5, according to the 100-days rule, which is the minimum required duration of the operation of ski resorts. The results of this study show that there will be major changes in the ski industry due to climate change. It is expected that operators, who already invested massive budgets into the development of ski slopes, will experience difficulties in management due to the deterioration of destinations and the loss of skiers due to climate change. Thus, managerial strategies that helps operators flexibly respond to climate change are required.

Bioremediation (Natural Attenuation and Biostimulation) of Diesel-Oil-Contaminated Soil in an Alpine Glacier Skiing Area

PubMed Central

Margesin, R.; Schinner, F.

2001-01-01

We investigated the feasibility of bioremediation as a treatment option for a chronically diesel-oil-polluted soil in an alpine glacier area at an altitude of 2,875 m above sea level. To examine the efficiencies of natural attenuation and biostimulation, we used field-incubated lysimeters (mesocosms) with unfertilized and fertilized (N-P-K) soil. For three summer seasons (July 1997 to September 1999), we monitored changes in hydrocarbon concentrations in soil and soil leachate and the accompanying changes in soil microbial counts and activity. A significant reduction in the diesel oil level could be achieved. At the end of the third summer season (after 780 days), the initial level of contamination (2,612 ± 70 μg of hydrocarbons g [dry weight] of soil−1) was reduced by (50 ± 4)% and (70 ± 2)% in the unfertilized and fertilized soil, respectively. Nonetheless, the residual levels of contamination (1,296 ± 110 and 774 ± 52 μg of hydrocarbons g [dry weight] of soil−1 in the unfertilized and fertilized soil, respectively) were still high. Most of the hydrocarbon loss occurred during the first summer season ([42 ± 6]% loss) in the fertilized soil and during the second summer season ([41 ± 4]% loss) in the unfertilized soil. In the fertilized soil, all biological parameters (microbial numbers, soil respiration, catalase and lipase activities) were significantly enhanced and correlated significantly with each other, as well as with the residual hydrocarbon concentration, pointing to the importance of biodegradation. The effect of biostimulation of the indigenous soil microorganisms declined with time. The microbial activities in the unfertilized soil fluctuated around background levels during the whole study. PMID:11425732

5 CFR 591.215 - Where does OPM collect prices in the COLA and DC areas?

Code of Federal Regulations, 2010 CFR

2010-01-01

...-housing data throughout the survey area, and for selected items such as golf, snow skiing, and air travel..., City of Manassas, and City of Manassas Park. 1 1 For selected items, such as golf, snow skiing, and air...

Let it snow: how snowfall and injury mechanism affect ski and snowboard injuries in Vail, Colorado, 2011-2012.

PubMed

Moore, S Jason; Knerl, Dana

2013-08-01

Current research examining the impact of mechanism of injury and daily snowfall amounts on injury severity among skiers and snowboarders is limited. The purpose of this study was to define correlations between injury mechanism and daily snowfall on injury patterns and severity among skiers and snowboarders. This observational study analyzed daily snowfall measurements coupled with trauma admissions during the 2011 and 2012 ski seasons from a Level III trauma center servicing a large North American ski resort. Post hoc adjusted analyses and multivariate modeling was used to determine independent predictors of increased injury severity. Six hundred forty-four trauma admissions were analyzed, with primary research considerations detailing the variances in injury severity resulting from collisions with other skiers or snowboarders and daily total snowfall. Findings demonstrated that collisions were independently associated with increased (1) injury severity (Injury Severity Score [ISS ≥ 16]) (odds ratio [OR], 3.9; 95% confidence interval [CI], 2.0-7.6; p < 0.001), (2) thoracic injury severity (Abbreviated Injury Scale [AIS] score ≥ 3) (OR, 7.5; 95% CI, 3.7-15.0; p < 0.001), and (3) renal injuries (OR, 3.2; 95% CI, 1.2-8.1; p = 0.017) as well as and axial skeleton fractures (OR, 4.5; 95% CI, 2.6-7.7; p < 0.001). In addition, mean ISS was significantly higher in the setting of a collision when compared with a fall (8.6 vs. 5.8; p < 0.001). Findings regarding total snowfall demonstrate a negative correlation between snowfall and injury severity (r = -0.08, p = 0.05); the majority (65.5%) of injuries were sustained when there was 1 inch or less of recent snowfall, and a snowfall total of 2 inches or less was independently associated with increased injury severity (ISS ≥ 16) (OR, 3.1; 95% CI, 1.1-9.1; p = 0.036). Collisions between snowsport enthusiasts and total trace snowfall predict an increase in injury severity among alpine skiers and snowboarders. Findings from this project may lead to an increased understanding of predictive factors contributing to injury, alter the diagnostic evaluation of patients, provide educational opportunities for alpine enthusiasts, and enhance resort safety initiatives tailored to ambient conditions.

Moore I postero-medial articular tibial fracture in alpine skiers: Surgical management and return to sports activity.

PubMed

Morin, Vincent; Pailhé, Régis; Sharma, Akash; Rouchy, René-Christopher; Cognault, Jérémy; Rubens-Duval, Brice; Saragaglia, Dominique

2016-06-01

Over the past 10 years, like many authors, we observed an increasing number of Moore I tibial plateau fractures related to alpine skiing for which the surgeon may face difficult choices regarding surgical approach and fixation means. Some authors have recently been suggesting a posterior approach associated to open reduction and osteosynthesis by a buttress plate. But in our knowledge there is no specific study on sports activity recovery after Moore I tibial fractures. The aim of this work was to assess sports activities and clinical outcomes after surgically treated Moore I tibial plateau fractures in an athletic population of skiers. We conducted a prospective case series between 2012 and 2014. This included fifteen patients aged 39.6±7 years whom presented with a Moore I tibial plateau fracture during a skiing accident. 12 cases (80%) presented with an associated tibial spine fracture. Treatment consisted of a standard antero-medial approach, with a medial para patellar arthrotomy to allow direct visualisation of articular reduction and spinal fixation. Two or three 6.5mm long cancellous bone screws were placed antero-posteriorly so as to ensure perfect compression of the fracture site. Radiological and functional results were assessed by an independent observer (Lysholm-Tegner, UCLA, KOOS scores) at the longest follow-up. Mean follow-up was 18.2±6 months (12-28). An immediate postoperative anatomical reduction was achieved in all cases and remained stable in time. At last follow-up Lysholm mean score was 85±14 points (59-100), UCLA score was 7.3±1.6 (4-10) and Tegner score was 4.6±1.3 (3-6). Mean KOOS score was 77±15 (54-97). 87% of patients had resumed their skiing activity and 93% were satisfied or very satisfied from their post-operative surgical outcome. We observed no pseudarthrosis or secondary varus displacement. In our series 87% of patients had resumed back to their sporting activities. Surgical management of Moore I tibial plateau fractures by isolated antero-posterior screwing provides excellent clinical and radiological results. The anteromedial incision has a dual advantage of anatomical reduction, tibial spine fixation (in 80% of our cases) and posteromedial fragment reduction. Copyright © 2016 Elsevier Ltd. All rights reserved.

From hydrological regimes to water use regimes: influence of the type of habitat on drinking water demand dynamics in alpine tourist resorts.

NASA Astrophysics Data System (ADS)

Calianno, Martin

2017-04-01

In the last decades, integrated water resources management studies produced integrated models that focus mainly on the assessment of water resources and water stress in the future. In some cases, socioeconomic development results to cause more impacts on the evolution of water systems than climate (Reynard et al., 2014). There is thus a need to develop demand-side approaches in the observation and modeling of human-influenced hydrological systems (Grouillet et al., 2015). We define the notion of water use cycle to differentiate water volumes that are withdrawn from the hydrological system and that circulate through anthropic hydro-systems along various steps: withdrawals, distribution, demands, consumption, restitution (Calianno et al., submitted). To address the spatial distribution and the temporal dynamics of the water use cycle, we define the concepts of water use basins and water use regimes (Calianno et al., submitted). The assessment of the temporal variability of water demands is important at thin time steps in touristic areas, where water resource regimes and water demands are highly variable. This is the case for are alpine ski resorts, where the high touristic season (winter) takes place during the low flow period in nival and glacio-nival basins. In this work, a monitoring of drinking water demands was undergone, at high temporal resolution, on different types of buildings in the ski resort of Megève (France). A dataset was created, from which a typology of water demand regimes was extracted. The analysis of these temporal signatures highlighted the factors influencing the volumes and the dynamics of drinking water demand. The main factors are the type of habitat (single family, collective, house, apartment blocks), the presence of a garden or an infrastructure linked to high standing chalets (pool, spa), the proportion of permanent and temporary habitat, the presence of snow in the ski resort. Also, temporalities linked to weekends and weekly tourism are observed. This typology of water demand regimes is at tool that can be developed to reproduce the temporal dynamics of water demands, when knowing the characteristics of habitat in a given region. References: Calianno M, Reynard E, Milano M (in prep). Water use cycle in tourist mountain territories: water demand basins and regimes. To be submitted to Water Resources Management. Calianno M, Reynard E, Milano M, Buchs A (submitted). Quantifier les usages de l'eau : concepts, terminologie et confusions. Submitted to VertigO. Grouillet B, Fabre J, Ruelland D, Dezetter A (2015) Historical reconstruction and 2050 projections of water demand under anthropogenic and climate changes in two contrasted mediterranean catchments. J Hydrol 522:684-696. Reynard E, Bonriposi M, Graefe O, Homewood C, Huss M, Kauzlaric M, Liniger H, Rey E, Rist S, Schädler B, Schneider F, Weingartner R (2014) Interdisciplinary assessment of complex regional water systems and their future evolution: how socioeconomic drivers can matter more than climate. WIREs Water 1(4):413-426.

75 FR 11511 - Rogue River-Siskiyou National Forest; Mt. Ashland Ski Area Expansion, Jackson County, OR

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-11

.... Ashland Ski Area (MASA) expansion, selecting Alternative 2 with some modifications adopted from... declaratory and injunctive relief on the grounds that the MASA expansion project violated both the NEPA and... instructed it to promptly enjoin the MASA expansion project contemplated in the 2004 ROD until the Forest...

Pediatric trauma in the Austrian Alps: the epidemiology of sport-related injuries in helicopter emergency medical service.

PubMed

Selig, Harald F; Hüpfl, Michael; Trimmel, Helmut; Voelckel, Wolfgang G; Nagele, Peter

2012-06-01

We aimed to examine the epidemiological characteristics and injury patterns of pediatric trauma in helicopter emergency medical service (HEMS) caused by sports/outdoor activities in alpine environment. This retrospective cohort study analyzed 912 primary HEMS missions for pediatric trauma (0-14 years of age) in Austrian Alps between 1 January 2006 and 30 June 2007. Children were stratified by age into toddlers (3-5 years), children in early (6-9 years), and late school age (10-14 years). The majority of pediatric sports-related trauma in alpine environment was caused by skiing (82.1%; n=749). Pediatric patients were predominately in late school age and boys (72.8%, n=664 and 61.0%, n=556, respectively) and a minority (16.0%, n=146) was severely injured. Overall, fracture (47.0%, n=429), contusion (17.9%, n=163), and traumatic brain injury (17.0%, n=155) were the most common prehospital diagnoses. The most frequent pattern of injury was related to the head/face and spine (36.3%, n=331). The knowledge about epidemiological characteristics of HEMS use for injured children in alpine environment may be essential for training requirements of HEMS crews and operational considerations of HEMS providers. The incidence of head and spinal injuries requires support for initiatives to promote helmet wear and appropriate risk behavior amongst skiers and snowboarders.

Altitude training considerations for the winter sport athlete.

PubMed

Chapman, Robert F; Stickford, Jonathon L; Levine, Benjamin D

2010-03-01

Winter sports events routinely take place at low to moderate altitudes, and nearly all Winter Olympic Games have had at least one venue at an altitude >1000 m. The acute and chronic effects of altitude can have a substantial effect on performance outcomes. Acutely, the decline in oxygen delivery to working muscle decreases maximal oxygen uptake, negatively affecting performance in endurance events, such as cross-country skiing and biathlon. The reduction in air resistance at altitude can dramatically affect sports involving high velocities and technical skill components, such as ski jumping, speed skating, figure skating and ice hockey. Dissociation between velocity and sensations usually associated with work intensity (ventilation, metabolic signals in skeletal muscle and heart rate) may impair pacing strategy and make it difficult to determine optimal race pace. For competitions taking place at altitude, a number of strategies may be useful, depending on the altitude of residence of the athlete and ultimate competition altitude, as follows. First, allow extra time and practice (how much is yet undetermined) for athletes to adjust to the changes in projectile motion; hockey, shooting, figure skating and ski jumping may be particularly affected. These considerations apply equally in the reverse direction; that is, for athletes practising at altitude but competing at sea level. Second, allow time for acclimatization for endurance sports: 3-5 days if possible, especially for low altitude (500-2000 m); 1-2 weeks for moderate altitude (2000-3000 m); and at least 2 weeks if possible for high altitude (>3000 m). Third, increase exercise-recovery ratios as much as possible, with 1:3 ratio probably optimal, and consider more frequent substitutions for sports where this is allowed, such as ice hockey. Fourth, consider the use of supplemental O(2) on the sideline (ice hockey) or in between heats (skating and Alpine skiing) to facilitate recovery. For competitions at sea level, the 'live high-train low' model of altitude training can help athletes in endurance events to maximize performance.

Explosive-residue compounds resulting from snow avalanche control in the Wasatch Mountains of Utah

USGS Publications Warehouse

Naftz, David L.; Kanagy, Leslie K.; Susong, David D.; Wydoski, Duane S.; Kanagy, Christopher J.

2003-01-01

A snow avalanche is a powerful force of nature that can play a significant role in developing mountain landscapes (Perla and Martinelli, 1975). More importantly, loss of life can occur when people are caught in the path of snow avalanches (Grossman, 1999). Increasing winter recreation, including skiing, snowboarding, snowmobiling, snowshoeing, and climbing in mountainous areas, has increased the likelihood of people encountering snow avalanches (fig. 1). Explosives are used by most ski areas and State highway departments throughout the Western United States to control the release of snow avalanches, thus minimizing the loss of human life during winter recreation and highway travel (fig. 2).Common explosives used for snow avalanche control include trinitrotoluene (TNT), pentaerythritoltetranitrate (PETN), cyclotrimethylenetrinitramine (RDX), tetrytol, ammonium nitrate, and nitroglycerin (Perla and Martinelli, 1975). During and after snowfall or wind loading of potential avalanche slopes, ski patrollers and Utah Department of Transportation personnel deliver explosive charges onto predetermined targets to artificially release snow avalanches, thereby rendering the slope safer for winter activities. Explosives can be thrown by hand onto target zones or shot from cannons for more remote delivery of explosive charges. Hand-delivered charges typically contain about 2 pounds of TNT or its equivalent (Perla and Martinelli, 1975).Depending on the size of the ski area, acreage of potential avalanche terrain, and weather conditions, the annual quantity of explosives used during a season of snow avalanche control can be substantial. For example, the three ski areas of Alta, Snowbird, and Brighton, plus the Utah Department of Transportation, may use as many as 11,200 hand charges per year (Wasatch Powderbird Guides, unpub. data, 1999) for snow avalanche control in Big and Little Cottonwood Canyons (fig. 3). If each charge is assumed to weigh 2 pounds, this equates to about 22,400 pounds of explosive hand charges per year. In addition, 2,240 to 3,160 Avalauncher rounds and 626 to 958 military artillery rounds (explosive mass not specified) are used each year by the three ski areas and the Utah Department of Transportation for snow avalanche control in Big and Little Cottonwood Canyons (Wasatch Powderbird Guides, unpub. data, 1999). The other ski area in Big Cottonwood Canyon, Brighton, uses about 2,000 pounds of explosives per year for snow avalanche control (Michele Weidner, Cirrus Ecological Solutions consultant, written commun., 2001).

ENERGY MANAGEMENT INNOVATION IN THE US SKI INDUSTRY

EPA Science Inventory

Ski areas represent a unique opportunity to develop innovative energy management practices in an industrial setting. Through a unique synergy of onsite generation, preferably by renewable sources and innovative technologies, and the energy storage potential of exis...

In-Frame Mutations in Exon 1 of SKI Cause Dominant Shprintzen-Goldberg Syndrome

PubMed Central

Carmignac, Virginie; Thevenon, Julien; Adès, Lesley; Callewaert, Bert; Julia, Sophie; Thauvin-Robinet, Christel; Gueneau, Lucie; Courcet, Jean-Benoit; Lopez, Estelle; Holman, Katherine; Renard, Marjolijn; Plauchu, Henri; Plessis, Ghislaine; De Backer, Julie; Child, Anne; Arno, Gavin; Duplomb, Laurence; Callier, Patrick; Aral, Bernard; Vabres, Pierre; Gigot, Nadège; Arbustini, Eloisa; Grasso, Maurizia; Robinson, Peter N.; Goizet, Cyril; Baumann, Clarisse; Di Rocco, Maja; Sanchez Del Pozo, Jaime; Huet, Frédéric; Jondeau, Guillaume; Collod-Beroud, Gwenaëlle; Beroud, Christophe; Amiel, Jeanne; Cormier-Daire, Valérie; Rivière, Jean-Baptiste; Boileau, Catherine; De Paepe, Anne; Faivre, Laurence

2012-01-01

Shprintzen-Goldberg syndrome (SGS) is characterized by severe marfanoid habitus, intellectual disability, camptodactyly, typical facial dysmorphism, and craniosynostosis. Using family-based exome sequencing, we identified a dominantly inherited heterozygous in-frame deletion in exon 1 of SKI. Direct sequencing of SKI further identified one overlapping heterozygous in-frame deletion and ten heterozygous missense mutations affecting recurrent residues in 18 of the 19 individuals screened for SGS; these individuals included one family affected by somatic mosaicism. All mutations were located in a restricted area of exon 1, within the R-SMAD binding domain of SKI. No mutation was found in a cohort of 11 individuals with other marfanoid-craniosynostosis phenotypes. The interaction between SKI and Smad2/3 and Smad 4 regulates TGF-β signaling, and the pattern of anomalies in Ski-deficient mice corresponds to the clinical manifestations of SGS. These findings define SGS as a member of the family of diseases associated with the TGF-β-signaling pathway. PMID:23103230

Root diversity in alpine plants: root length, tensile strength and plant age

NASA Astrophysics Data System (ADS)

Pohl, M.; Stroude, R.; Körner, C.; Buttler, A.; Rixen, C.

2009-04-01

A high diversity of plant species and functional groups is hypothesised to increase the diversity of root types and their subsequent effects for soil stability. However, even basic data on root characteristics of alpine plants are very scarce. Therefore, we determined important root characteristics of 13 plant species from different functional groups, i.e. grasses, herbs and shrubs. We excavated the whole root systems of 62 plants from a machine-graded ski slope at 2625 m a.s.l. and analysed the rooting depth, the horizontal root extension, root length and diameter. Single roots of plant species were tested for tensile strength. The age of herbs and shrubs was determined by growth-ring analysis. Root characteristics varied considerably between both plant species and functional groups. The rooting depth of different species ranged from 7.2 ± 0.97 cm to 20.5 ± 2.33 cm, but was significantly larger in the herb Geum reptans (70.8 ± 10.75 cm). The woody species Salix breviserrata reached the highest horizontal root extensions (96.8 ± 25.5 cm). Most plants had their longest roots in fine diameter classes (0.5

Prevalence of cardiovascular diseases among alpine skiers and hikers in the Austrian Alps.

PubMed

Faulhaber, Martin; Flatz, Markus; Gatterer, Hannes; Schobersberger, Wolfgang; Burtscher, Martin

2007-01-01

Mountain sports, especially hiking and alpine skiing, are very popular. It is speculated that a high percentage of hikers and skiers are older and have cardiovascular diseases, but little is known about the real frequency of cardiovascular diseases in mountaineers and skiers. The goal of this study was to provide data on the prevalence of cardiovascular diseases (coronary artery disease with and without myocardial infarction, hypertension, and arrhythmias) of a representative sample of hikers and skiers in the Austrian Alps. Questionnaire results of 1431 hikers and 1043 skiers were included in the evaluation. Regarding the whole sample, 12.7% (11.0 to 14.4) of the hikers and 11.2% (9.3 to 13.1) of the skiers are afflicted with at least one type of cardiovascular disease. The frequency of cardiovascular diseases is age dependent and more pronounced in men, but only small differences were detected between hikers and skiers. It can be assumed that 4 to 5 million hikers and skiers with known cardiovascular diseases are active in the Alps annually. Scientific research should provide the basis of an optimal risk management for this large group of persons.

In-frame mutations in exon 1 of SKI cause dominant Shprintzen-Goldberg syndrome.

PubMed

Carmignac, Virginie; Thevenon, Julien; Adès, Lesley; Callewaert, Bert; Julia, Sophie; Thauvin-Robinet, Christel; Gueneau, Lucie; Courcet, Jean-Benoit; Lopez, Estelle; Holman, Katherine; Renard, Marjolijn; Plauchu, Henri; Plessis, Ghislaine; De Backer, Julie; Child, Anne; Arno, Gavin; Duplomb, Laurence; Callier, Patrick; Aral, Bernard; Vabres, Pierre; Gigot, Nadège; Arbustini, Eloisa; Grasso, Maurizia; Robinson, Peter N; Goizet, Cyril; Baumann, Clarisse; Di Rocco, Maja; Sanchez Del Pozo, Jaime; Huet, Frédéric; Jondeau, Guillaume; Collod-Beroud, Gwenaëlle; Beroud, Christophe; Amiel, Jeanne; Cormier-Daire, Valérie; Rivière, Jean-Baptiste; Boileau, Catherine; De Paepe, Anne; Faivre, Laurence

2012-11-02

Shprintzen-Goldberg syndrome (SGS) is characterized by severe marfanoid habitus, intellectual disability, camptodactyly, typical facial dysmorphism, and craniosynostosis. Using family-based exome sequencing, we identified a dominantly inherited heterozygous in-frame deletion in exon 1 of SKI. Direct sequencing of SKI further identified one overlapping heterozygous in-frame deletion and ten heterozygous missense mutations affecting recurrent residues in 18 of the 19 individuals screened for SGS; these individuals included one family affected by somatic mosaicism. All mutations were located in a restricted area of exon 1, within the R-SMAD binding domain of SKI. No mutation was found in a cohort of 11 individuals with other marfanoid-craniosynostosis phenotypes. The interaction between SKI and Smad2/3 and Smad 4 regulates TGF-β signaling, and the pattern of anomalies in Ski-deficient mice corresponds to the clinical manifestations of SGS. These findings define SGS as a member of the family of diseases associated with the TGF-β-signaling pathway. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Home advantage in the Winter Paralympic Games 1976-2014.

PubMed

Wilson, Darryl; Ramchandani, Girish

2017-01-01

There is a limited amount of home advantage research concerned with winter sports. There is also a distinct lack of studies that investigate home advantage in the context of para sport events. This paper addresses this gap in the knowledge by examining home advantage in the Winter Paralympic Games. Using a standardised measure of success, we compared the performances of host nations at home with their own performances away from home between 1976 and 2014. Both country level and individual sport level analysis is conducted for this time period. Comparisons are also drawn with the Winter Olympic Games since 1992, the point from which both the Winter Olympic Games and the Winter Paralympic Games have been hosted by the same nations and in the same years. Clear evidence of a home advantage effect in the Winter Paralympic Games was found at country level. When examining individual sports, only alpine skiing and cross country skiing returned a significant home advantage effect. When comparing home advantage in the Winter Paralympic Games with the Winter Olympic Games for the last seven host nations (1992-2014), we found that home advantage was generally more pronounced (although not a statistically significant difference) in the case of the former. The causes of home advantage in the Winter Paralympic Games are unclear and should be investigated further.

Simulating the potential effects of climate change in two Colorado basins and at two Colorado ski areas

USGS Publications Warehouse

Battaglin, William; Hay, Lauren E.; Markstrom, Steve

2011-01-01

The mountainous areas of Colorado are used for tourism and recreation, and they provide water storage and supply for municipalities, industries, and agriculture. Recent studies suggest that water supply and tourist industries such as skiing are at risk from climate change. In this study, a distributed-parameter watershed model, the Precipitation-Runoff Modeling System (PRMS), is used to identify the potential effects of future climate on hydrologic conditions for two Colorado basins, the East River at Almont and the Yampa River at Steamboat Springs, and at the subbasin scale for two ski areas within those basins.Climate-change input files for PRMS were generated by modifying daily PRMS precipitation and temperature inputs with mean monthly climate-change fields of precipitation and temperature derived from five general circulation model (GCM) simulations using one current and three future carbon emission scenarios. All GCM simulations of mean daily minimum and maximum air temperature for the East and Yampa River basins indicate a relatively steady increase of up to several degrees Celsius from baseline conditions by 2094. GCM simulations of precipitation in the two basins indicate little change or trend in precipitation, but there is a large range associated with these projections. PRMS projections of basin mean daily streamflow vary by scenario but indicate a central tendency toward slight decreases, with a large range associated with these projections.Decreases in water content or changes in the spatial extent of snowpack in the East and Yampa River basins are important because of potential adverse effects on water supply and recreational activities. PRMS projections of each future scenario indicate a central tendency for decreases in basin mean snow-covered area and snowpack water equivalent, with the range in the projected decreases increasing with time. However, when examined on a monthly basis, the projected decreases are most dramatic during fall and spring. Presumably, ski area locations are picked because of a tendency to receive snow and keep snowpack relative to the surrounding area. This effect of ski area location within the basin was examined by comparing projections of March snow-covered area and snowpack water equivalent for the entire basin with more local projections for the portion of the basin that represents the ski area in the PRMS models. These projections indicate a steady decrease in March snow-covered area for the basins but only small changes in March snow-covered area at both ski areas for the three future scenarios until around 2050. After 2050, larger decreases are possible, but there is a large range in the projections of future scenarios. The rates of decrease for snowpack water equivalent and precipitation that falls as snow are similar at the basin and subbasin scale in both basins. Results from this modeling effort show that there is a wide range of possible outcomes for future snowpack conditions in Colorado. The results also highlight the differences between projections for entire basins and projections for local areas or subbasins within those basins.

78 FR 33047 - Humboldt-Toiyabe National Forest, Carson Ranger District Mt. Rose Ski Tahoe-Atoma Area...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-03

... the effects of a proposal from Mt. Rose Ski Tahoe (Mt. Rose) to expand its lift and terrain network... to create the Atoma lift and trail ``Pod'' to the north of the Mt. Rose Highway. The proposed Atoma... facilitate construction and [[Page 33048

Earth Observations taken by the Expedition 18 Crew

NASA Image and Video Library

2008-10-24

ISS018-E-005353 (24 Oct. 2008) --- Breckenridge and Copper Mountain ski slopes, Colorado are featured in this image photographed by an Expedition 18 crewmember on the International Space Station. Located in a section of the Rocky Mountains which extend through central Colorado, Tenmile Range and Copper Mountain provide the ideal location and landscape for popular winter sports. In this view, the Breckenridge and Copper Mountain ski areas are clearly visible as the snow covered ski runs stand out among the surrounding darker forest. Tenmile Range has mountain peaks that are named Peaks 1 through Peaks 10. The Breckenridge ski area use Peaks 7 through Peaks 10 which range from 12,631 feet (3,850 meters) to 13,615 feet (4,150 meters) high. Tenmile Canyon is a north northeast-trending fault-controlled valley running nearly 3,000 feet (914.4 meters) deep that serves as the boundaries for Tenmile Creek running through the center of the photo. The snow-covered peaks clearly delineate the tree line at an elevation of around 11,000 feet (3,350 meters). In the winter, this area's annual average snowfall ranges between 284 inches (7.21 meters) at Copper Mountain to 300 inches (7.62 meters) a year at Breckenridge. Before recreation became the main industry, miners were attracted to the area in the mid-1800's following discoveries of gold, silver, lead, and zinc. The towns of Breckenridge and Wheeler Junction (at the base of Copper Mountain ski area) were born out of the surge to settle the West during the Pike's Peak Gold Rush. While this image records snow on the peaks of Tenmile Range, the months of October and November 2008 saw little accumulation of snow pack in the area of Breckenridge. The situation changed in early December 2008 however, when more snow fell in eight days than in the preceding two months. The late, but significant, snowfall boosted the snow pack back to expected levels for this time of year.

[Comparison between ski and snowboarding accidents. Current overview from the ski area Arosa (Switzerland) (1988/89 to 1994/95)].

PubMed

Fischler, L; Röthlisberger, M

1996-06-11

The ski resort of Arosa (Switzerland) is geographically isolated and has recorded it winter sports accidents since 1969. Based on this reliable data, the ski (3877 in total) and snowboard (512 in total) accidents of the last seven years were statistically analyzed. The study showed that snowboarding isn't much more dangerous than skiing the number of accidents was about the same in both groups, whereas snowboarders were less likely to be admitted to a hospital or to get injured by collision. The average age of snowboarders was 21.6 years, almost 20 years lower than that of the skiers. Both sexes were about equally represented. Most snowboarders had injuries of the upper extremity (14% fractures of the radius, 9% distortions), particularly because of falling backward after losing balance. In both groups (skiers and snowboarders) 60% of all injuries were of low grade, which did not lead to long absence from work. The results are discussed and compared with already existing publications.

Investigations on socio economic indicators of French Alps ski industry from an explicit spatial modelling of managed snow on ski slopes

NASA Astrophysics Data System (ADS)

Spandre, Pierre; François, Hugues; Morin, Samuel; George-Marcelpoil, Emmanuelle; Lafaysse, Matthieu

2017-04-01

Investigations of the capacity of ski resorts to anticipate, cope with and recover from the impact of natural snow scarcity through snow management (grooming, snowmaking) have been realized in most of the major regions in terms of international ski offer although not in the French Alps hitherto. The present work therefore introduces an innovative approach for the investigation of socio economic implications of changes in snow conditions for the French Alps ski resorts based on a panel of 129 resorts representing 96% of the total French Alps ski lifts infrastructures. We integrated detailed spatial representations of ski resorts (including priority areas for snowmaking equipment) along with physically based snowpack modelling (including the physical impact of grooming and snowmaking). The viability of ski resorts was further adressed thanks to a commonly used rule based on the snow season duration at the village and ski lifts average elevations along with the development of original viability indicators of snow conditions in the French Alps ski resorts based on the specific periods for the economic success of winter sports: Christmas and February school holidays. Such indicators were correlated to the number of ski lifts tickets sales over the 2001 - 2014 period and proved to be relevant to investigate and predict the evolutions of ski lifts tickets sales under the current ski market conditions in the French Alps. Our results outlined the contrast of snow conditions between French Alps ski resorts, even when accounting for snow management, particularly regarding the geographical location of resorts (Southern versus Northern Alps), the size and related elevation range of ski resorts. Our physically based approach also allowed to compute the water and energy requirements for the production of Machine Made snow since the start of the development of snowguns in the French Alps. Our computations proved to be strongly correlated to the observed amounts of water from the existing literature and confirmed that the increasing surface equipped with snowmaking facilities in the French Alps is the major factor for the increasing water and energy requirements since 1985. Such approach therefore provides objective information on the impact of snow conditions on the economic activity of winter sports in the French Alps under past and present conditions and may be considered as a relevant approach for further investigations, including the impact of climate change on the winter tourism in the French Alps.

Alpine biodiversity and assisted migration: The case of the American pika (Ochotona princeps)

USGS Publications Warehouse

Wilkening, Jennifer L.; Ray, Chris; Ramsay, Nathan G.; Klingler, Kelly

2015-01-01

Alpine mammals are predicted to be among the species most threatened by climate change, due to the projected loss and further fragmentation of alpine habitats. As temperature or precipitation regimes change, alpine mammals may also be faced with insurmountable barriers to dispersal. The slow rate or inability to adjust to rapidly shifting environmental conditions may cause isolated alpine species to become locally extirpated, resulting in reduced biodiversity. One proposed method for mitigating the impacts of alpine species loss is assisted migration. This method, which involves translocating a species to an area with more favourable climate and habitat characteristics, has become the subject of debate and controversy in the conservation community. The uncertainty associated with climate change projections, coupled with the thermal sensitivity of many alpine mammals, makes it difficult to a priori assess the efficacy of this technique as a conservation management tool. Here we present the American pika (Ochotona princeps) as a case study. American pikas inhabit rocky areas throughout the western US, and populations in some mountainous areas have become locally extirpated in recent years. We review known climatic and habitat requirements for this species, and also propose protocols designed to reliably identify favourable relocation areas. We present data related to the physiological constraints of this species and outline specific requirements which must be addressed for translocation of viable populations, including wildlife disease and genetic considerations. Finally, we discuss potential impacts on other alpine species and alpine communities, and overall implications for conserving alpine biodiversity in a changing climate.

Involvement of c-Ski oncoprotein in carcinogenesis of cholangiocacinoma induced by Opisthorchis viverrini and N-nitrosodimethylamine.

PubMed

Boonmars, Thidarut; Wu, Zhiliang; Boonjaruspinyo, Sirintip; Puapairoj, Anucha; Kaewsamut, Butsara; Nagano, Isao; Pinlaor, Somchai; Yongvanit, Puangrat; Wonkchalee, Orasa; Juasook, Amornrat; Sudsarn, Pakkayanee; Srisawangwong, Tuanchai

2011-06-01

Opisthorchiasis is the major public health problem in the endemic areas of Thailand and Laos because Opisthorchis viverrini infection causes serious hepatobiliary diseases including CCA. The molecular mechanism of the CCA carcinogenesis induced by the infection remains obscure. To reveal the potential genes and signaling pathways to involve in the carcinogenesis, the present study investigated the expression of c-Ski, an oncogene, and two TGF-β signaling pathway relative genes, TGF-β and Smad4, during the development of CCA induced by O. viverrini infection in hamster model, and in human opisthorchiasis associated CCA. The results showed that the expression of c-Ski gene was greatly up-regulated during the carcinogenesis of CCA in hamster model. The overexpression of c-Ski was confirmed by immunohistological staining result which showed the increased expression of c-Ski protein in cytoplasm of the epithelial lining of hepatic bile ducts. Moreover, the immunohistological staining of the specimens of human opisthorchiasis associated CCA revealed the up-regulated expression of c-Ski and Smad4 proteins in the cytoplasm of the epithelial lining of hepatic bile ducts and stomal fibrosis respectively. The expression of TGF-β and Smad4 were up-regulated, which expression kinetics was time-dependent of CCA development. These results suggest that c-Ski is likely involved in the carcinogenesis of CCA induced by O. viverrini infection through regulating TGF-β signaling pathway.

Arthroscopically assisted treatment of lateral tibial plateau fractures in skiers: use of a cannulated reduction system.

PubMed

Holzach, P; Matter, P; Minter, J

1994-08-01

A prospective study was performed on 16 patients with lateral tibial plateau fractures. All injuries were associated with alpine or cross-country skiing. Included in the study were those patients with an articular surface depression of > or = 2 mm with radiographic findings consistent with the AO/ASIF classification of tibial plateau fractures (41 B2.2/B3.1). A combined procedure was performed with arthroscopic visualization of the knee joint and utilization of a cannulated plateau elevator. All fractures were reduced with this device with subsequent autogenous bone graft and, when indicated, transverse cancellous lag screw fixation. Follow-up was 1-6.5 years for the 16 patients, with all but two reporting resumption of activity to preinjury levels.

"no snow - no skiing excursion - consequences of climatic change?"

NASA Astrophysics Data System (ADS)

Neunzig, Thilo

2014-05-01

Climatology and climate change have become central topics in Geography at our school. Because of that we set up a climatological station at our school. The data are an important basis to observe sudden changes in the weather. The present winter (2013/2014) shows the importance of climate change in Alzey / Germany. In winter many students think of the yearly skiing trip to Schwaz / Austria which is part of our school programme. Due to that the following questions arise: Will skiing still be possible if climate change accelerates? How are the skiing regions in the Alpes going to change? What will happen in about 20 years? How does artificial snow change the landscape and the skiing sport? Students have to be aware of the ecological damage of skiing trips. Each class has to come up with a concept how these trips can be as environmentally friendly as possible. - the trip is for a restricted number of students only (year 8 only) - a small skiing region is chosen which is not overcrowded - snow has to be guaranteed in the ski area to avoid the production of artificial snow (avoidance of high water consumption) - the bus arrives with a class and returns with the one that had been there before These are but a few ideas of students in order to make their trip as environmentally friendly as possible. What is missing is only what is going to happen in the future. What will be the effect of climate change for skiing regions in the secondary mountains? How is the average temperature for winter going to develop? Are there possibilities for summer tourism (e.g. hiking) instead of skiing in winter? The students are going to try to find answers to these questions which are going to be presented on a poster on the GIFT-Workshop in Vienna.

Enhancing Industry-based Dissemination of an Occupational Sun Protection Program with Theory-based Strategies Employing Personal Contact

PubMed Central

Buller, David B.; Andersen, Peter A.; Walkosz, Barbara J.; Scott, Michael D.; Cutter, Gary R.; Dignan, Mark B.; Kane, Ilima L.; Zhang, Xiao

2012-01-01

Purpose Industry-based strategies for dissemination of an evidence-based occupational sun protection program, Go Sun Smart (GSS), were tested. Design Two dissemination strategies were compared in a randomized trial in 2004 – 2007. Setting The North American ski industry. Subjects Ski areas in the United States and Canada (n=69) and their senior managers (n=469). Intervention Employers received GSS through a Basic Dissemination Strategy (BDS) from the industry’s professional association which included conference presentations and free starter kits. Half of the areas also received the Enhanced Dissemination Strategy (EDS), in which project staff met face-to-face with managers and made ongoing contacts to support program use. Measures Observation of program materials in use and managers’ reports on communication about sun protection. Analysis The effects of two alternative dissemination strategies were compared on program use using PROC MIXED in SAS, adjusted for covariates using 1-tailed p-values. Results Ski areas receiving the EDS used more GSS materials (M=7.36) than those receiving the BDS (M=5.17; F=7.82, p<.01). Managers from more areas receiving the EDS reported communicating about sun protection in employee newsletters/flyers (M=0.97, p=.04), in guest email messages (M=0.75, p=.02), and on ski area websites (M=0.38, p=.02) than those receiving the BDS (M=0.84, 0.50, 0.15, respectively). Conclusion Industry professional associations play an important role in disseminating prevention programs; however, active personal communication may be essential to ensure increased implementation fidelity. PMID:22747318

Wind and fairness in ski jumping: A computer modelling analysis.

PubMed

Jung, Alexander; Müller, Wolfram; Staat, Manfred

2018-06-25

Wind is closely associated with the discussion of fairness in ski jumping. To counter-act its influence on the jump length, the International Ski Federation (FIS) has introduced a wind compensation approach. We applied three differently accurate computer models of the flight phase with wind (M1, M2, and M3) to study the jump length effects of various wind scenarios. The previously used model M1 is accurate for wind blowing in direction of the flight path, but inaccuracies are to be expected for wind directions deviating from the tangent to the flight path. M2 considers the change of airflow direction, but it does not consider the associated change in the angle of attack of the skis which additionally modifies drag and lift area time functions. M3 predicts the length effect for all wind directions within the plane of the flight trajectory without any mathematical simplification. Prediction errors of M3 are determined only by the quality of the input data: wind velocity, drag and lift area functions, take-off velocity, and weight. For comparing the three models, drag and lift area functions of an optimized reference jump were used. Results obtained with M2, which is much easier to handle than M3, did not deviate noticeably when compared to predictions of the reference model M3. Therefore, we suggest to use M2 in future applications. A comparison of M2 predictions with the FIS wind compensation system showed substantial discrepancies, for instance: in the first flight phase, tailwind can increase jump length, and headwind can decrease it; this is opposite of what had been anticipated before and is not considered in the current wind compensation system in ski jumping. Copyright © 2018 Elsevier Ltd. All rights reserved.

Earth observations taken by the Expedition 12 crew

NASA Image and Video Library

2005-11-15

ISS012-E-11144 (11 Dec. 2005) --- Sierra Nevada, Spain is featured in this image photographed by an Expedition 12 crew member on the International Space Station. According to scientists, the Sierra Nevada, part of the Betic Cordillera of southern Spain, was formed during the Alpine Orogeny (or mountain-building event) that also formed the European Alps to the east and the Atlas Mountains of northern Africa across the Mediterranean Sea to the south. The Sierra as observed today formed during the Tertiary Period (65 to 1.8 million years ago) during collision of the African and Eurasian continental plates. The former Tethys Sea also closed during this time period, the scientists say, and the Mediterranean Sea is the largest surviving remnant basin of the ancient Tethys. The Sierra Nevada in the Granada province of Spain is perhaps the southernmost skiing location in all of Europe. Veleta Peak, at an elevation of 3,398 meters above sea level, is a popular destination for skiers and snowboarders. The rapid transition from lofty ski runs to Mediterranean beaches within a few hours’ drive has made the Sierra Nevada region popular for both outdoor and urban tourism. This photograph depicts the Veleta Peak region of the range and illustrates the sharp contrast between the snow capped mountains, adjacent dry lowlands to the west and north, and the Mediterranean Sea to the south.

The SKI*HI Model: Programming for Hearing Impaired Infants through Home Intervention, Home Visit Curriculum. Fourth Edition.

ERIC Educational Resources Information Center

Clark, Thomas C.; Watkins, Susan

The manual describes the SKI*HI Model, a comprehensive approach to identification and home intervention treatment of hearing impaired children and their families. The model features home programing in four basic areas: the home hearing aid program (nine lessons which facilitate the proper fit and acceptance of amplification by the child), home…

Golden eagle indifference to heli-skiing and military helicopters in northern Utah

Treesearch

Teryl G. Grubb; David K. Delaney; William W. Bowerman; Michael R. Wierda

2010-01-01

In 2006-2007, during Wasatch Powderbird Guides (WPG) permit renewal for heli-skiing in the Tri-Canyon Area (TCA) of the Wasatch Mountains, Utah, USA, we recorded 303 helicopter passes between 0 m and 3,000 m (horizontal distance) near >30 individual golden eagles (Aquila chrysaetos) in 22 nesting territories, through passive observation and active experimentation...

Alpine ecosystems

Treesearch

P.W. Rundel; C.I. Millar

2016-01-01

Alpine ecosystems are typically defined as those areas occurring above treeline, while recognizing that alpine ecosystems at a local scale may be found below this boundary for reasons including geology, geomorphology, and microclimate. The lower limit of the alpine ecosystems, the climatic treeline, varies with latitude across California, ranging from about 3500 m in...

Space Radar Image of Mammoth Mountain, California

NASA Image and Video Library

1999-05-01

These two false-color composite images of the Mammoth Mountain area in the Sierra Nevada Mountains, Calif., show significant seasonal changes in snow cover. The image at left was acquired by the Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar aboard the space shuttle Endeavour on its 67th orbit on April 13, 1994. The image is centered at 37.6 degrees north latitude and 119 degrees west longitude. The area is about 36 kilometers by 48 kilometers (22 miles by 29 miles). In this image, red is L-band (horizontally transmitted and vertically received) polarization data; green is C-band (horizontally transmitted and vertically received) polarization data; and blue is C-band (horizontally transmitted and received) polarization data. The image at right was acquired on October 3, 1994, on the space shuttle Endeavour's 67th orbit of the second radar mission. Crowley Lake appears dark at the center left of the image, just above or south of Long Valley. The Mammoth Mountain ski area is visible at the top right of the scene. The red areas correspond to forests, the dark blue areas are bare surfaces and the green areas are short vegetation, mainly brush. The changes in color tone at the higher elevations (e.g. the Mammoth Mountain ski area) from green-blue in April to purple in September reflect changes in snow cover between the two missions. The April mission occurred immediately following a moderate snow storm. During the mission the snow evolved from a dry, fine-grained snowpack with few distinct layers to a wet, coarse-grained pack with multiple ice inclusions. Since that mission, all snow in the area has melted except for small glaciers and permanent snowfields on the Silver Divide and near the headwaters of Rock Creek. On October 3, 1994, only discontinuous patches of snow cover were present at very high elevations following the first snow storm of the season on September 28, 1994. For investigations in hydrology and land-surface climatology, seasonal snow cover and alpine glaciers are critical to the radiation and water balances. SIR-C/X-SAR is a powerful tool because it is sensitive to most snowpack conditions and is less influenced by weather conditions than other remote sensing instruments, such as Landsat. In parallel with the operational SIR-C data processing, an experimental effort is being conducted to test SAR data processing using the Jet Propulsion Laboratory's massively parallel supercomputing facility, centered around the Cray Research T3D. These experiments will assess the abilities of large supercomputers to produce high throughput SAR processing in preparation for upcoming data-intensive SAR missions. The images released here were produced as part of this experimental effort. http://photojournal.jpl.nasa.gov/catalog/PIA01753

Economic Impacts of Climate Change on Winter Tourism: Challenges for Ski Area Operators

NASA Astrophysics Data System (ADS)

Damm, A.; Köberl, J.; Prettenthaler, F.; Töglhofer, C.

2012-04-01

Increasing temperatures and snow scarce winter seasons pose a big challenge for the winter tourism industry. Changing natural snow reliability influences tourism demand and ski area operators are faced with an enhanced need of technical snow production. The goal of the present research work is to analyze the economic effects of technical snow production under future climate conditions. Snowmaking as an adaptation strategy to climate change impacts on the ski tourism industry is already taken into consideration in several studies from a scientific perspective concerning snowmaking potentials under future climate conditions and the impacts on ski season length (e.g. Scott et al. 2003; Scott & McBoyle 2007; Hennessy et al. 2008; Steiger 2010). A few studies considered economic aspects of technical snowmaking (e.g. Teich et al. 2007; Gonseth 2008). However, a detailed analysis of the costs and benefits of snowmaking under future climate and snow conditions based on sophisticated climate and snow models has not been carried out yet. The present study addresses the gap of knowledge concerning the economic profitability of prospective snowmaking requirements under future climate scenarios. We carry out a detailed cost-revenue analysis of snowmaking under current and future climate conditions for a case study site in Styria (Austria) using dynamic investment models. The starting point of all economic calculations is the daily demand for artificial snow that determines the requirements for additional snowmaking investments and additional operating costs. The demand for artificial snow is delivered by the snow cover model AMUNDSEN (see Strasser et al. 2011) and is driven by four climate scenarios. Apart from future climate conditions the profitability of snowmaking depends on changes in costs and visitor numbers. The results of a ski tourism demand model analyzing daily visitor numbers and their dependencies of prevailing weather conditions enter the cost-revenue analysis of snowmaking and enable the determination of the immediate benefits in terms of additional revenues of ski ticket sales. Furthermore, we conduct an econometric analysis of how snowmaking investments changed ski ticket prices in previous years, as the positive effects of snowmaking on snow reliability could be offset in the longer term by the effects of higher prices for skiing, possibly resulting in lower demand.

Area burned in alpine treeline ecotones reflects region-wide trends

Treesearch

C. Alina Cansler; Donald McKenzie; Charles B. Halpern

2016-01-01

The direct effects of climate change on alpine treeline ecotones – the transition zones between subalpine forest and non-forested alpine vegetation – have been studied extensively, but climate-induced changes in disturbance regimes have received less attention. To determine if recent increases in area burned extend to these higher-elevation landscapes, we analysed...

Investigating potential effects of heli-skiing on golden eagles in the Wasatch Mountains, Utah

Treesearch

Teryl G. Grubb; David K. Delaney; William W. Bowerman

2007-01-01

Implementing further research was beyond the scope of the U.S. Forest Service's 2004 Final Environmental Impact Statement (FEIS) and 2005 Wasatch Powderbird Guides (WPG) Special Use Permit Renewal process for heli-skiing in the Tri-Canyon Area in the Wasatch Mountains, just east of Salt Lake City, Utah. However, in their Record of Decision the Wasaatch-Cache (WCNF...

Sports injuries and illnesses during the Winter Olympic Games 2010.

PubMed

Engebretsen, Lars; Steffen, Kathrin; Alonso, Juan Manuel; Aubry, Mark; Dvorak, Jiri; Junge, Astrid; Meeuwisse, Willem; Mountjoy, Margo; Renström, Per; Wilkinson, Mike

2010-09-01

Identification of high-risk sports, including their most common and severe injuries and illnesses, will facilitate the identification of sports and athletes at risk at an early stage. To analyse the frequencies and characteristics of injuries and illnesses during the XXI Winter Olympic Games in Vancouver 2010. All National Olympic Committees' (NOC) head physicians were asked to report daily the occurrence (or non-occurrence) of newly sustained injuries and illnesses on a standardised reporting form. In addition, the medical centres at the Vancouver and Whistler Olympic clinics reported daily on all athletes treated for injuries and illnesses. Physicians covering 2567 athletes (1045 females, 1522 males) from 82 NOCs participated in the study. The reported 287 injuries and 185 illnesses resulted in an incidence of 111.8 injuries and 72.1 illnesses per 1000 registered athletes. In relation to the number of registered athletes, the risk of sustaining an injury was highest for bobsleigh, ice hockey, short track, alpine freestyle and snowboard cross (15-35% of registered athletes were affected in each sport). The injury risk was lowest for the Nordic skiing events (biathlon, cross country skiing, ski jumping, Nordic combined), luge, curling, speed skating and freestyle moguls (less than 5% of registered athletes). Head/cervical spine and knee were the most common injury locations. Injuries were evenly distributed between training (54.0%) and competition (46.0%; p=0.18), and 22.6% of the injuries resulted in an absence from training or competition. In skeleton, figure and speed skating, curling, snowboard cross and biathlon, every 10th athlete suffered from at least one illness. In 113 illnesses (62.8%), the respiratory system was affected. At least 11% of the athletes incurred an injury during the games, and 7% of the athletes an illness. The incidence of injuries and illnesses varied substantially between sports. Analyses of injury mechanisms in high-risk Olympic winter sports are essential to better direct injury-prevention strategies.

Enhancing industry-based dissemination of an occupational sun protection program with theory-based strategies employing personal contact.

PubMed

Buller, David B; Andersen, Peter A; Walkosz, Barbara J; Scott, Michael D; Cutter, Gary R; Dignan, Mark B; Kane, Ilima L; Zhang, Xiao

2012-01-01

Industry-based strategies for dissemination of an evidence-based occupational sun protection program, Go Sun Smart (GSS), were tested. Two dissemination strategies were compared in a randomized trial in 2004-2007. The North American ski industry. Ski areas in the United States and Canada (n  =  69) and their senior managers (n  =  469). Employers received GSS through a basic dissemination strategy (BDS) from the industry's professional association that included conference presentations and free starter kits. Half of the areas also received the enhanced dissemination strategy (EDS), in which project staff met face-to-face with managers and made ongoing contacts to support program use. Observation of program materials in use and managers' reports on communication about sun protection. The effects of two alternative dissemination strategies were compared on program use using PROC MIXED in SAS, adjusted for covariates using one-tailed p values. Ski areas receiving the EDS used more GSS materials (x¯  =  7.36) than those receiving the BDS (x¯  =  5.17; F  =  7.82, p < .01). Managers from more areas receiving the EDS reported communicating about sun protection in employee newsletters/flyers (x¯  =  .97, p  =  .04), in guest e-mail messages (x¯  =  .75, p  =  .02), and on ski area Web sites (x¯  =  .38, p  =  .02) than those receiving the BDS (x¯  =  .84, .50, .15, respectively). Industry professional associations play an important role in disseminating prevention programs; however, active personal communication may be essential to ensure increased implementation fidelity.

Testing a Theory-Based Health Communication Program: A Replication of Go Sun Smart in Outdoor Winter Recreation

PubMed Central

ANDERSEN, PETER A.; BULLER, DAVID B.; WALKOSZ, BARBARA J.; MALOY, JULIE; SCOTT, MICHAEL D.; CUTTER, GARY R.; DIGNAN, MARK B.

2010-01-01

The epidemic of preventable skin cancer in the United States creates an urgent need for health communication campaigns to improve sun protection. Go Sun Smart (GSS), a theory-driven multichannel health communication campaign showed positive effects on sun safety behaviors of employees and guests in a randomized trial at high-altitude ski areas. In this article we report findings from the North American GSS campaign for guests at ski areas that comprosed the original control-group resorts, replicating the results of the original guest intervention. Results showed that after GSS was deployed, guests at the original control group ski areas increased sun protection and reported greater recall of sun safety messages. Conversely, GSS had no effect on sunburning attitudes or self-efficacy beliefs. Like the original GSS guest intervention, the present study found that greater exposure to GSS messages was associated with greater use of sunscreen, sunscreen lip balm, and face covering, but not gloves or overall sun protection. There was no evidence that GSS decreased sunburning or attitudes and self-efficacy beliefs regarding sun safety. PMID:19466647

Comparison of moss and pine needles as bioindicators of transboundary polycyclic aromatic hydrocarbon pollution in central Japan.

PubMed

Oishi, Yoshitaka

2018-03-01

Atmospheric pollution by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem, especially in Asia, as PAHs can severely affect ecologically important mountainous areas. Using pine needles and mosses as bio-indicators, this study examined PAH pollution in a mountainous study area and evaluated the influence of transboundary PAHs. PAHs in urban areas were also evaluated for comparison. The study sites were alpine areas and urban areas (inland or coastal cities) across central Japan, in the easternmost part of Asia where atmospheric pollutants are transported from mainland Asia. The mean PAH concentrations of pine needles and mosses were 198.9 ± 184.2 ng g -1 dry weight (dw) and 131.8 ± 60.7 ng g -1 dw (mean ± SD), respectively. Pine needles preferentially accumulated PAHs with low molecular weights (LMW PAHs) and exhibited large differences in both PAH concentration and isomer ratios between alpine and urban sites. These differences can be explained by the strong influence of LMW PAHs emitted from domestic sources, which decreased and changed during transport from urban to alpine sites due to dry/wet deposition and photodegradation. In contrast, mosses accumulated a higher ratio of PAHs with high molecular weight (HMW PAHs). A comparison of isomer ratios showed that the PAH source for alpine moss was similar to that for northern coastal cities, which are typically influenced by long-transported PAHs from East Asia. Thus, these results indicate that alpine moss can also be strongly affected by the transboundary PAHs. It is likely that the uptake characteristics of moss, alpine climate, and alpine locations far from urban areas can strengthen the influence of transboundary pollution. Based on these results, the limitations and most effective use of bioindicators of PAH pollution for preserving alpine ecosystems are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Numerical model of the catchments of the oziąbel and wołczyński strumień rivers - Wołczyn municipality

NASA Astrophysics Data System (ADS)

Olichwer, Tomasz; Wcisło, Marek; Staśko, Stanisław; Buczyński, Sebastian; Modelska, Magdalena; Tarka, Robert

2012-10-01

The article presents a numerical model designed for determining groundwater dynamics and water balance of the catchments of the Oziąbel (Czarna Woda) river and the Wołczyński Strumień river in Wołczyn region. Hydrogeological mapping and modelling research covered the area of 238.9 km2. As a result of measurements performed in 2008-2009, flows were determined in major rivers and water table positions were measured at 26 points. In the major part of the area described, the water table, lying at the depth of 1.5-18.7 m, has unconfined character, and the aquifer is built of Neogene (Quaternary) sands and gravels. In the area under study, groundwaters are drawn from 6 wells with total withdrawal of 6133 m3/d. The numerical modelling was performed with the use of Visual Modflow 3.1.0 software. The area was partitioned by a discretization grid with a step size l = 250 m. The conceptual model of the hydrogeological system is based on hydrological data gathered over a period of one year, data from HYDRO bank database, cross-sections and maps. The boundaries of the modelled hydrogeological system were established on the watersheds of the Wołczyński Strumień river and the Oziąbel river, apart from the areas where they run together. The modelled area was extended (271.5 km2) around the Wołczyński Strumień river catchment to achieve a more effective mapping of the anthropogenic impact on its balance and the hydrodynamic system of the catchment area. The structure is characterised by the occurrence of one or rarely two aquifers separated by a pack of Quaternary clays. The investigation produced a detailed water balance and its components.

Skier triggering of backcountry avalanches with skilled route selection

NASA Astrophysics Data System (ADS)

Sinickas, Alexandra; Haegeli, Pascal; Jamieson, Bruce

2015-04-01

Jamieson (2009) provided numerical estimates for the baseline probabilities of triggering an avalanche by a backcountry skier making fresh tracks without skilled route selection as a function of the North American avalanche danger scale (i.e., hazard levels Low, Moderate, Considerable, High and Extreme). Using the results of an expert survey, he showed that triggering probabilities while skiing directly up, down or across a trigger zone without skilled route selection increase roughly by a factor of 10 with each step of the North American avalanche danger scale (i.e. hazard level). The objective of the present study is to examine the effect of skilled route selection on the relationship between triggering probability and hazard level. To assess the effect of skilled route selection on triggering probability by hazard level, we analysed avalanche hazard assessments as well as reports of skiing activity and triggering of avalanches from 11 Canadian helicopter and snowcat operations during two winters (2012-13 and 2013-14). These reports were submitted to the daily information exchange among Canadian avalanche safety operations, and reflect professional decision-making and route selection practices of guides leading groups of skiers. We selected all skier-controlled or accidentally triggered avalanches with a destructive size greater than size 1 according to the Canadian avalanche size classification, triggered by any member of a guided group (guide or guest). These operations forecast the avalanche hazard daily for each of three elevation bands: alpine, treeline and below treeline. In contrast to the 2009 study, an exposure was defined as a group skiing within any one of the three elevation bands, and consequently within a hazard rating, for the day (~4,300 ratings over two winters). For example, a group that skied below treeline (rated Moderate) and treeline (rated Considerable) in one day, would receive one count for exposure to Moderate hazard, and one count for exposure to Considerable hazard. While the absolute values for triggering probability cannot be compared to the 2009 study because of different definitions of exposure, our preliminary results suggest that with skilled route selection the triggering probability is similar all hazard levels, except for extreme for which there are few exposures. This means that the guiding teams of backcountry skiing operations effectively control the hazard from triggering avalanches with skilled route selection. Groups were exposed relatively evenly to Low hazard (1275 times or 29% of total exposure), Moderate hazard (1450 times or 33 %) and Considerable hazard (1215 times or 28 %). At higher levels, the exposure reduced to roughly 380 times (9 % of total exposure) to High hazard, and only 13 times (0.3 %) to Extreme hazard. We assess the sensitivity of the results to some of our key assumptions.

A half century of change in alpine treeline patterns at Glacier National Park, Montana, U.S.A.

USGS Publications Warehouse

Klasner, F.L.; Fagre, D.B.

2002-01-01

Using sequential aerial photography, we identified changes in the spatial distribution of subalpine fir (Abies lasiocarpa) habitat at the alpine treeline ecotone. Six 40-ha study sites in the McDonald Creek drainage of Glacier National Park contained subalpine fir forests that graded into alpine tundra. Over a 46-yr period, altitudinal changes in the location of alpine treeline ecotone were not observed. However, over this 46-yr period the area of krummholz, patch-forest, and continuous canopy forest increased by 3.4%, and tree density increased within existing patches of krummholz and patch-forest. Change in subalpine fir vegetation patterns within 100 m of trails was also compared to areas without trails. Within 100 m of trails, the number of small, discrete krummholz stands increased compared to areas without trails, but there was no significant change in total krummholz area. We used historical terrestrial photography to expand the period (to 70 yr) considered. This photography supported the conclusions that a more abrupt ecotone transition developed from forest to tundra at alpine treeline, that tree density within forested areas increased, and that krummholz became fragmented along trails. This local assessment of fine-grained change in the alpine treeline ecotone provides a comparative base for looking at ecotone change in other mountain regions throughout the world.

Plants in alpine environments

USGS Publications Warehouse

Germino, Matthew J.

2014-01-01

Alpine and subalpine plant species are of special interest in ecology and ecophysiology because they represent life at the climate limit and changes in their relative abundances can be a bellwether for climate-change impacts. Perennial life forms dominate alpine plant communities, and their form and function reflect various avoidance, tolerance, or resistance strategies to interactions of cold temperature, radiation, wind, and desiccation stresses that prevail in the short growing seasons common (but not ubiquitous) in alpine areas. Plant microclimate is typically uncoupled from the harsh climate of the alpine, often leading to substantially warmer plant temperatures than air temperatures recorded by weather stations. Low atmospheric pressure is the most pervasive, fundamental, and unifying factor for alpine environments, but the resulting decrease in partial pressure of CO2 does not significantly limit carbon gain by alpine plants. Factors such as tree islands and topographic features create strong heterogeneous mosaics of microclimate and snow cover that are reflected in plant community composition. Factors affecting tree establishment and growth and formation of treeline are key to understanding alpine ecology. Carbohydrate and other carbon storage, rapid development in a short growing season, and physiological function at low temperature are prevailing attributes of alpine plants. A major contemporary research theme asks whether chilling at alpine-treeline affects the ability of trees to assimilate the growth resources and particularly carbon needed for growth or whether the growth itself is limited by the alpine environment. Alpine areas tend to be among the best conserved, globally, yet they are increasingly showing response to a range of anthropogenic impacts, such as atmospheric deposition.

An exploratory comparison of motivations and crowding norms between ethnic groups in downhill ski areas of New York state and Korea

Treesearch

Chung In Park; Chad Dawson

1998-01-01

This study explores the concept that ethnic groups have different motivations and crowding norms when downhill skiing and that visiting and immigrant ethnic groups would respond more like their original ethnic group than they would be like their host ethnic group. The four ethnic groups or sampling strata that were surveyed in this study were: White Anglo skiers at...

Multi-parameter monitoring of the construction and evolution of a snow bridge over a crevasse on an Alpine glacier

NASA Astrophysics Data System (ADS)

Ravanel, Ludovic; Malet, Emmanuel; Batoux, Philippe

2017-04-01

Snow bridges that form over the crevasses of the Alpine glaciers allow mountaineers and skiers to cross them easily but constitute an important danger in case of rupture. Between 2008 and 2014, 37 injured persons and 13 deaths related to falls into crevasse were recorded (i.e. an average of two deaths per year) on the glaciers of the French side of the Mont Blanc massif - out of the famous Vallée Blanche ski route, which however embodies an important part of the aid related to falls into crevasses. To understand the construction and evolution of these fragile structures, instrumentation was set up on the Glacier du Géant, at 3450 m a.s.l., near the Aiguille du Midi (3842 m a.s.l.), on the French side of the Mont Blanc massif, close to a crevasse whose bridge had recently collapsed over a length of 37 m. The maximum width of the crevasse in this area is 6 m. At the top of a 7-m-high pole - to prevent future snowfalls -, sensors have been installed in September 2016 to measure different snow and weather parameters: air temperature, wind speed and direction, snow height. An automatic camera surveys the crevasse and the snow bridge geometry. Several other sensors monitor the temperature of snow and air in the crevasse. In addition, an extensometer was installed into the crevasse to measure the evolution of its width. The results of the first 6 months of survey are presented, including the formation of the bridge in mid-November, during a period of snowfall associated with a strong wind. Although the instrumentation is well suited to the high mountain conditions, its maintenance is delicate due to the strong instability of the environment (glacier movements and extreme weather conditions, primarily) but the results of this work will bring new glaciological knowledges which should participate in a better safety on glaciers.

Erosion Processes, Sediment Transport and Hydrological Responses Due to Land Use Changes in Serbian Ski Resorts

NASA Astrophysics Data System (ADS)

Ristic, R.; Radic, B.; Vasiljevic, N.; Nikic, Z.; Malusevic, I.

2012-04-01

The construction or improvement of Serbian ski resorts provoked intensive erosion processes, sediment transport and hydrological responses due to land use changes, affecting the surrounding environment and even endangering the functionality of the built objects. The dominant disturbing activities (clear cuttings, trunk transport, machine grading of slopes, huge excavations, and access road construction) were followed by the activities during skiing and non skiing periods (skiing, usage of snow groomers, moving of vehicles and tourists, forestry activities and overgrazing). These activities put a lot of pressure on the environment, including the removal or compaction of the surface soil layer, the reduction of the infiltration capacity, the destruction or degradation of the vegetation cover, the intensifying of the surface runoff and the development of erosion processes. The most affected ski runs were surveyed (scale 1:1000) and all damages were mapped and classified during the summers of 2007-2010. The development of rills and gullies was measured at experimental plots (100x60 m), and the survey data were entered into a GIS application. The area sediment yield and the intensity of erosion processes were estimated on the basis of the "Erosion Potential Method"(EPM). The changes in hydrological conditions were estimated by comparing the computed values of maximal discharges in the conditions before and after massive activities in the ski resorts, as well as by using the local hydrological records. The determination of maximal discharges was achieved using a combined method: the synthetic unit hydrograph (maximum ordinate of unit runoff, qmax) and the Soil Conservation Service (SCS, 1979) methodology (deriving effective rainfall, Pe, from total precipitation, Pb). The determination was performed for AMC III (Antecedent Moisture Conditions III: high water content in the soil and significantly reduced infiltration capacity). The computations of maximal discharges were based on the regional analysis of lag time (Ristić, 2003), the internal daily distribution of precipitation (Janković,1994) and the classification of soil hydrologic groups for runoff curve numbers (CN) determination (Đorović, 1984). The applied restoration and erosion control measures have stopped the degradation processes and helped to rehabilitate the appearance and functions of the landscape. The findings of this survey highlight the importance of considering geomorphic and hydrological factors under the conditions of significant changes in land usage. The results of this investigation can contribute to the improvement of planning processes and the implementation of development projects in ski areas.

Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yi; Pirisi, Lucia; Creek, Kim E., E-mail: creekk@sccp.sc.edu

2013-09-15

We compared the levels of the Ski oncoprotein, an inhibitor of transforming growth factor-beta (TGF-β) signaling, in normal human keratinocytes (HKc), HPV16 immortalized HKc (HKc/HPV16), and differentiation resistant HKc/HPV16 (HKc/DR) in the absence and presence of TGF-β. Steady-state Ski protein levels increased in HKc/HPV16 and even further in HKc/DR, compared to HKc. TGF-β treatment of HKc, HKc/HPV16, and HKc/DR dramatically decreased Ski. TGF-β-induced Ski degradation was delayed in HKc/DR. Ski and phospho-Ski protein levels are cell cycle dependent with maximal Ski expression and localization to centrosomes and mitotic spindles during G2/M. ShRNA knock down of Ski in HKc/DR inhibited cellmore » proliferation. More intense nuclear and cytoplasmic Ski staining and altered Ski localization were found in cervical cancer samples compared to adjacent normal tissue in a cervical cancer tissue array. Overall, these studies demonstrate altered Ski protein levels, degradation and localization in HPV16-transformed human keratinocytes and in cervical cancer. - Highlights: • Ski oncoprotein levels increase during progression of HPV16-transformed cells. • Ski and phospho-Ski protein levels are cell cycle dependent. • Ski knock-down in HPV16-transformed keratinocytes inhibited cell proliferation. • Cervical cancer samples overexpress Ski.« less

Ungulate herbivory on alpine willow in the Sangre de Cristo Mountains of Colorado

USGS Publications Warehouse

Zeigenfuss, L.C.; Schoenecker, K.A.; Amburg, L.K.V.

2011-01-01

In many areas of the Rocky Mountains, elk (Cervus elaphus) migrate from low-elevation mountain valleys during spring to high-elevation subalpine and alpine areas for the summer. Research has focused on the impacts of elk herbivory on winter-range plant communities, particularly on woody species such as willow and aspen; however, little information is available on the effects of elk herbivory on alpine willows. In the Sangre de Cristo Mountains of south central Colorado, select alpine areas appear to receive high levels of summer elk herbivory, while other areas are nearly unbrowsed. In 2005 and 2008, we measured willow height, cover, and utilization on sites that appeared to be used heavily by elk, as well as on sites that appeared to be used lightly, to determine differences between these communities over time. We found less willow cover and shorter willows at sites that received higher levels of browsing compared to those that had lower levels of browsing. Human recreational use was greater at lightly browsed sites than at highly browsed sites. From 2005 to 2008, willow utilization declined, and willow cover and height increased at sites with heavy browsing, likely owing to ownership change of adjacent valley land which led to (1) removal of grazing competition from, cattle at valley locations and (2) increased human use in alpine areas, which displaced elk. We discuss the implications of increased human use and climate change on elk use of these alpine habitats. ?? 2011.

Soil Survey: Fraser Alpine Area, Colorado

Treesearch

J. L. Retzer

1962-01-01

The Fraser Alpine Area is a rough, mountainous area that lies approximately 50 miles west of Denver, Colo., and covers approximately 134 square miles. About seven-eighths of it is above timberline, and all is within the boundaries of Arapaho National Forest, U.S. Forest Service. The land in the Area is not suitable for cultivation and has never been farmed.

Professional ski waxers' exposure to PFAS and aerosol concentrations in gas phase and different particle size fractions.

PubMed

Nilsson, Helena; Kärrman, Anna; Rotander, Anna; van Bavel, Bert; Lindström, Gunilla; Westberg, Håkan

2013-04-01

Previous reports show that professional ski waxers have elevated blood levels of perfluorinated substances (PFAS) such as perfluorooctanoate (PFOA) and are exposed to very high concentrations of PFAS in air during ski waxing. Aerosol exposure increases the risk of cardiovascular disease, and PFOA is a potential hormonal disruptor and carcinogen, and can affect the fatty acid metabolism. Animal studies have shown that 8:2 FTOH can undergo biotransformation to PFOA. For the first time, this study presents an occupational scenario of professional ski waxers who are exposed to extremely high dust levels as well as per- and polyfluorinated compounds. Personal and fixed measurements of total aerosol, inhalable and respirable fractions were performed during World Cup events 2007-2010. The occupational exposure limit (OEL) is exceeded in 37% of the personal measurements with concentrations up to 15 mg m(-3) in air. There are differences between personal and area total aerosol concentrations with levels from personal measurements twice as high as those from the area measurements. The personal levels for FTOH ranged up to 996 μg m(-3) (mean = 114 μg m(-3)) and for PFOA up to 4.89 μg m(-3) (mean = 0.53 μg m(-3)) in ENV+ sorbent samples as compared to the general exposure levels from air reaching only low ng m(-3) (<30 ng m(-3)) levels. FTOHs were not detected in aerosols but PFOA showed an average level of 12 μg m(-3) (range = 1.2-47 μg m(-3)). The ski waxers' exposure to paraffin fumes and PFAS is not in compliance with the occupational exposure standards and by far exceed the general populations' exposure. Preventive measures must be taken to minimize the exposure in this occupational group.

Risk assessment of mountain infrastructure destabilization in the French Alps

NASA Astrophysics Data System (ADS)

Duvillard, Pierre-Allain; Ravanel, Ludovic; Deline, Philip

2015-04-01

In the current context of imbalance of geosystems in connection with the rising air temperature for several decades, high mountain environments are especially affected by the shrinkage of glaciers and the permafrost degradation which can trigger slope movements in the rock slopes (rockfall, rock avalanches) or in superficial deposits (slides, rock glacier rupture, thermokarst). These processes generate a risk of direct destabilization for high mountain infrastructure (huts, cable-cars...) in addition to indirect risks for people and infrastructure located on the path of moving rock masses. We here focus on the direct risk of infrastructure destabilization due to permafrost degradation and/or glacier shrinkage in the French Alps. To help preventing these risks, an inventory of all the infrastructure was carried out with a GIS using different data layers among which the Alpine Permafrost Index Map and inventories of the French Alps glaciers in 2006-2009, 1967-1971 and at the end of the Little Ice Age. 1769 infrastructures have been identified in areas likely characterized by permafrost and/or possibly affected by glacier shrinkage. An index of risk of destabilization has been built to identify and to rank infrastructure at risk. This theoretical risk index includes a characterization of hazards and a diagnosis of the vulnerability. The value of hazard is dependent on passive factors (topography, lithology, geomorphological context...) and on so-considered active factors (thermal state of the permafrost, and changing constraints on slopes related to glacier shrinkage). The diagnosis of vulnerability has meanwhile been established by combining the level of potential damage to the exposed elements with their operational and financial values. The combination of hazard and vulnerability determines a degree of risk of infrastructure destabilization (from low to very high). Field work and several inventories of infrastructure damages were used to validate it. The application of this risk index for infrastructure in the French Alps indicates 999 infrastructures potentially at risk, among 0.2 % are characterized by a very high risk and 4.4 % by a high risk of destabilization. The risk unequally affects massifs: 55 % of the infrastructure at risk are in the Vanoise massif (Savoie) due to the large number of high-altitude ski resorts in this area. The Mont-Blanc massif (Haute-Savoie) includes only 6.5 % of the infrastructure at risk. Furthermore, 71 % of the exposed infrastructure are ski-lifts.

Staying cool: preadaptation to temperate climates required for colonising tropical alpine-like environments.

PubMed

Gehrke, Berit

2018-01-01

Plant species tend to retain their ancestral ecology, responding to temporal, geographic and climatic changes by tracking suitable habitats rather than adapting to novel conditions. Nevertheless, transitions into different environments or biomes still seem to be common. Especially intriguing are the tropical alpine-like areas found on only the highest mountainous regions surrounded by tropical environments. Tropical mountains are hotspots of biodiversity, often with striking degrees of endemism at higher elevations. On these mountains, steep environmental gradients and high habitat heterogeneity within small spaces coincide with astounding species diversity of great conservation value. The analysis presented here shows that the importance of in situ speciation in tropical alpine-like areas has been underestimated. Additionally and contrary to widely held opinion, the impact of dispersal from other regions with alpine-like environments is relatively minor compared to that of immigration from other biomes with a temperate (but not alpine-like) climate. This suggests that establishment in tropical alpine-like regions is favoured by preadaptation to a temperate, especially aseasonal, freezing regime such as the cool temperate climate regions in the Tropics. Furthermore, emigration out of an alpine-like environment is generally rare, suggesting that alpine-like environments - at least tropical ones - are species sinks.

Staying cool: preadaptation to temperate climates required for colonising tropical alpine-like environments

PubMed Central

Gehrke, Berit

2018-01-01

Abstract Plant species tend to retain their ancestral ecology, responding to temporal, geographic and climatic changes by tracking suitable habitats rather than adapting to novel conditions. Nevertheless, transitions into different environments or biomes still seem to be common. Especially intriguing are the tropical alpine-like areas found on only the highest mountainous regions surrounded by tropical environments. Tropical mountains are hotspots of biodiversity, often with striking degrees of endemism at higher elevations. On these mountains, steep environmental gradients and high habitat heterogeneity within small spaces coincide with astounding species diversity of great conservation value. The analysis presented here shows that the importance of in situ speciation in tropical alpine-like areas has been underestimated. Additionally and contrary to widely held opinion, the impact of dispersal from other regions with alpine-like environments is relatively minor compared to that of immigration from other biomes with a temperate (but not alpine-like) climate. This suggests that establishment in tropical alpine-like regions is favoured by preadaptation to a temperate, especially aseasonal, freezing regime such as the cool temperate climate regions in the Tropics. Furthermore, emigration out of an alpine-like environment is generally rare, suggesting that alpine-like environments – at least tropical ones – are species sinks. PMID:29706788

Water resources: Research network to track alpine water

USDA-ARS?s Scientific Manuscript database

The water cycle in alpine environments worldwide supplies fresh water to vast downstream areas inhabited by more than half of humanity. The International Network for Alpine Research Catchment Hydrology (INARCH) was launched this year by the Global Energy and Water Exchanges project of the World Clim...

Ski jumping takeoff in a wind tunnel with skis.

PubMed

Virmavirta, Mikko; Kivekäs, Juha; Komi, Paavo

2011-11-01

The effect of skis on the force-time characteristics of the simulated ski jumping takeoff was examined in a wind tunnel. Takeoff forces were recorded with a force plate installed under the tunnel floor. Signals from the front and rear parts of the force plate were collected separately to examine the anteroposterior balance of the jumpers during the takeoff. Two ski jumpers performed simulated takeoffs, first without skis in nonwind conditions and in various wind conditions. Thereafter, the same experiments were repeated with skis. The jumpers were able to perform very natural takeoff actions (similar to the actual takeoff) with skis in wind tunnel. According to the subjective feeling of the jumpers, the simulated ski jumping takeoff with skis was even easier to perform than the earlier trials without skis. Skis did not much influence the force levels produced during the takeoff but they still changed the force distribution under the feet. Contribution of the forces produced under the rear part of the feet was emphasized probably because the strong dorsiflexion is needed for lifting the skis to the proper flight position. The results presented in this experiment emphasize that research on ski jumping takeoff can be advanced by using wind tunnels.

Suppression of p53 Activity through the Cooperative Action of Ski and Histone Deacetylase SIRT1*

PubMed Central

Inoue, Yasumichi; Iemura, Shun-ichiro; Natsume, Tohru; Miyazawa, Keiji; Imamura, Takeshi

2011-01-01

Ski was originally identified as an oncogene based on the fact that Ski overexpression transformed chicken and quail embryo fibroblasts. Consistent with these proposed oncogenic roles, Ski is overexpressed in various human tumors. However, whether and how Ski functions in mammalian tumorigenesis has not been fully investigated. Here, we show that Ski interacts with p53 and attenuates the biological functions of p53. Ski overexpression attenuated p53-dependent transactivation, whereas Ski knockdown enhanced the transcriptional activity of p53. Interestingly, Ski bound to the histone deacetylase SIRT1 and stabilized p53-SIRT1 interaction to promote p53 deacetylation, which subsequently decreased the DNA binding activity of p53. Consistent with the ability of Ski to inactivate p53, overexpressing Ski desensitized cells to genotoxic drugs and Nutlin-3, a small-molecule antagonist of Mdm2 that stabilizes p53 and activates the p53 pathway, whereas knocking down Ski increased the cellular sensitivity to these agents. These results indicate that Ski negatively regulates p53 and suggest that the p53-Ski-SIRT1 axis is an attractive target for cancer therapy. PMID:21149449

The role of permafrost and soil water in distribution of alpine grassland and its NDVI dynamics on the Qinghai-Tibetan Plateau

NASA Astrophysics Data System (ADS)

Wang, Xiaoyun; Yi, Shuhua; Wu, Qingbai; Yang, Kun; Ding, Yongjian

2016-12-01

Soil temperature and soil water are two important factors controlling vegetation growth. Climate warming and associated permafrost degradation might change these soil conditions and affect alpine grassland on the Qinghai-Tibetan Plateau. However, our current understanding of the role of soil temperature and water at the plateau scale is inadequate. In this study, we used plateau scale soil water content, frozen soil type, vegetation index and land surface temperature datasets to investigate the spatial distribution, limiting factors of vegetation growth and normalized difference vegetation index (NDVI) changing trends in two major alpine grasslands, alpine meadow and alpine steppe, in relation to soil temperature and soil water conditions. Our results showed that: 1) alpine meadow is mainly distributed in seasonal frozen soil areas (55.90% of alpine meadow) with a soil water content between 0.15 and 0.25 m3/m3 and alpine steppe is mainly found in seasonal frozen and sub-stable permafrost areas (69.38% of alpine steppe) with a soil water content between 0.05 and 0.20 m3/m3; 2) at the plateau scale, there were 35.6% (more in colder regions) of alpine meadow pixels and 33.6% (more in wetter regions) of alpine steppe pixels having increase NDVI changing trends during 1982-2012, respectively; and the values having decrease NDVI changing trends are 7.3% and 9.7%, respectively; and 3) the vegetation growth of alpine meadow is mainly limited by soil temperature, while that of alpine steppe is limited by both soil temperature and soil water. We also find the limiting factors of temperature or water can only explain < 50% variation of vegetation growth trends in alpine grasslands. Our findings warrant the use of process-based ecosystem models to consider other factors, such as grazing, erosion and soil texture, among others, in addition to soil temperature and water to make proper projections when simulating the responses of vegetation growth to climate warming in alpine grasslands with different hydro-thermal conditions.

Combined cistrome and transcriptome analysis of SKI in AML cells identifies SKI as a co-repressor for RUNX1

PubMed Central

Feld, Christine; Sahu, Peeyush; Frech, Miriam; Finkernagel, Florian; Nist, Andrea; Stiewe, Thorsten; Bauer, Uta-Maria; Neubauer, Andreas

2018-01-01

Abstract SKI is a transcriptional co-regulator and overexpressed in various human tumors, for example in acute myeloid leukemia (AML). SKI contributes to the origin and maintenance of the leukemic phenotype. Here, we use ChIP-seq and RNA-seq analysis to identify the epigenetic alterations induced by SKI overexpression in AML cells. We show that approximately two thirds of differentially expressed genes are up-regulated upon SKI deletion, of which >40% harbor SKI binding sites in their proximity, primarily in enhancer regions. Gene ontology analysis reveals that many of the differentially expressed genes are annotated to hematopoietic cell differentiation and inflammatory response, corroborating our finding that SKI contributes to a myeloid differentiation block in HL60 cells. We find that SKI peaks are enriched for RUNX1 consensus motifs, particularly in up-regulated SKI targets upon SKI deletion. RUNX1 ChIP-seq displays that nearly 70% of RUNX1 binding sites overlap with SKI peaks, mainly at enhancer regions. SKI and RUNX1 occupy the same genomic sites and cooperate in gene silencing. Our work demonstrates for the first time the predominant co-repressive function of SKI in AML cells on a genome-wide scale and uncovers the transcription factor RUNX1 as an important mediator of SKI-dependent transcriptional repression. PMID:29471413

Study of the slope of the linear relationship between retention and mobile phase composition (Snyder-Soczewiñski model) in normal phase liquid chromatography with bonded and charge-transfer phases.

PubMed

Wu, Di; Lucy, Charles A

2016-12-02

The Snyder model and the Soczewiñski model are compared on classic NPLC bonded phases using literature data, and on the charge transfer 2, 4-dinitroanilinopropyl (DNAP) column using experimentally collected data. Overall, the Snyder model slightly better predicts the n-slope than the Soczewiñski model. However, both models give comparable uncertainty in predicting n-slope for a given compound. The number of aromatic double bonds was the most suitable descriptor for estimating the relative n-slope of PAHs, as it correlated with behavior better than the number of aromatic rings and is simpler to calculate than the solute adsorption area. On the DNAP phase, a modified Soczewiñski model is suggested to allow for the significant contribution of the aromatic rings to the n-slope. For classic NPLC bonded phases and DNAP columns, the contribution of polar group to the n-slope parallels the adsorption energy of each polar group. Copyright © 2016 Elsevier B.V. All rights reserved.

Strong genetic structure corresponds to small-scale geographic breaks in the Australian alpine grasshopper Kosciuscola tristis.

PubMed

Slatyer, Rachel A; Nash, Michael A; Miller, Adam D; Endo, Yoshinori; Umbers, Kate D L; Hoffmann, Ary A

2014-10-02

Mountain landscapes are topographically complex, creating discontinuous 'islands' of alpine and sub-alpine habitat with a dynamic history. Changing climatic conditions drive their expansion and contraction, leaving signatures on the genetic structure of their flora and fauna. Australia's high country covers a small, highly fragmented area. Although the area is thought to have experienced periods of relative continuity during Pleistocene glacial periods, small-scale studies suggest deep lineage divergence across low-elevation gaps. Using both DNA sequence data and microsatellite markers, we tested the hypothesis that genetic partitioning reflects observable geographic structuring across Australia's mainland high country, in the widespread alpine grasshopper Kosciuscola tristis (Sjösted). We found broadly congruent patterns of regional structure between the DNA sequence and microsatellite datasets, corresponding to strong divergence among isolated mountain regions. Small and isolated mountains in the south of the range were particularly distinct, with well-supported divergence corresponding to climate cycles during the late Pliocene and Pleistocene. We found mixed support, however, for divergence among other mountain regions. Interestingly, within areas of largely contiguous alpine and sub-alpine habitat around Mt Kosciuszko, microsatellite data suggested significant population structure, accompanied by a strong signature of isolation-by-distance. Consistent patterns of strong lineage divergence among different molecular datasets indicate genetic breaks between populations inhabiting geographically distinct mountain regions. Three primary phylogeographic groups were evident in the highly fragmented Victorian high country, while within-region structure detected with microsatellites may reflect more recent population isolation. Despite the small area of Australia's alpine and sub-alpine habitats, their low topographic relief and lack of extensive glaciation, divergence among populations was on the same scale as that detected in much more extensive Northern hemisphere mountain systems. The processes driving divergence in the Australian mountains might therefore differ from their Northern hemisphere counterparts.

Ski protein levels increase during in vitro progression of HPV16-immortalized human keratinocytes and in cervical cancer

PubMed Central

Chen, Yi; Pirisi, Lucia; Creek, Kim E.

2013-01-01

We compared the levels of the Ski oncoprotein, an inhibitor of transforming growth factor-beta (TGF-β) signaling, in normal human keratinocytes (HKc), HPV16 immortalized HKc (HKc/HPV16), and differentiation resistant HKc/HPV16 (HKc/DR) in the absence and presence of TGF-β. Steady-state Ski protein levels increased in HKc/HPV16 and even further in HKc/DR, compared to HKc. TGF-β treatment of HKc, HKc/HPV16, and HKc/DR dramatically decreased Ski. TGF-β-induced Ski degradation was delayed in HKc/DR. Ski and phospho-Ski protein levels are cell cycle dependent with maximal Ski expression and localization to centrosomes and mitotic spindles during G2/M. ShRNA knock down of Ski in HKc/DR inhibited cell proliferation. More intense nuclear and cytoplasmic Ski staining and altered Ski localization were found in cervical cancer samples compared to adjacent normal tissue in a cervical cancer tissue array. Overall, these studies demonstrate altered Ski protein levels, degradation and localization in HPV16-transformed human keratinocytes and in cervical cancer. PMID:23809940

Identification of Ski as a target for Aurora A kinase

PubMed Central

Mosquera, Jocelyn; Armisen, Ricardo; Zhao, Hong Ling; Rojas, Diego A.; Maldonado, Edio; Tapia, Julio C; Colombo, Alicia; Hayman, Michael J; Marcelain, Katherine

2011-01-01

Ski is a negative regulator of the transforming growth factor-β and other signalling pathways. The absence of SKI in mouse fibroblasts leads to chromosome segregation defects and genomic instability, suggesting a role for Ski during mitosis. At this stage, Ski is phosphorylated but to date little is known about the kinases involved in this process. Here, we show that Aurora A kinase is able to phosphorylate Ski in vitro. In vivo, Aurora A and Ski co-localized at the centrosomes and co-immunoprecipitated. Conversely, a C-terminal truncation mutant of Ski (SkiΔ491–728) lacking a coiled-coil domain, displayed decreased centrosomal localization. This mutant no longer co-immunoprecipitated with Aurora-A in vivo, but was still phosphorylated in vitro, indicating that the Ski-Aurora A interaction takes place at the centrosomes. These data identify Ski as a novel target of Aurora A and contribute to an understanding of the role of these proteins in the mitotic process. PMID:21600873

Hydrological significance of soil frost for pre-alpine areas

NASA Astrophysics Data System (ADS)

Stähli, Manfred

2017-03-01

Soil frost can have a substantial impact on water flows at the soil surface and-potentially-alter the dynamics of catchment runoff. While these findings are mainly based on studies from alpine and Northern-latitude areas (including permafrost areas), little is known about the significance of soil frost for hydrology in pre-alpine areas, i.e. the region at the transition from central European lowlands to high-alpine areas. Here I synthesize soil temperature data and soil frost observations from ten sites in Switzerland to assess the occurrence of soil frost and to determine its impact on catchment runoff. In addition, a well-established numerical model was used to reconstruct the presence of soil frost in two first-order catchments for single runoff events and winters. The data clearly demonstrates that shallow soil frost has formed regularly in this altitudinal range over the past decade. The presence of a frozen soil surface was found to be highly variable among the sites under study and did not significantly correlate with altitude or forest density. For the first-order catchments, it was not possible to relate important flood peaks or increased runoff coefficients to winter situations with substantial soil frost. Thus, the present analysis suggests that although soil frost is widespread and regularly occurring at this altitudinal range, it has no significant impact on winter runoff in pre-alpine watersheds.

The influence of grip on oxygen consumption and leg forces when using classical style roller skis.

PubMed

Ainegren, M; Carlsson, P; Laaksonen, M S; Tinnsten, M

2014-04-01

The purpose of this study was to investigate the influence of classical style roller skis' grip (static friction coefficients, μS) on cross-country skiers' oxygen consumption and leg forces during treadmill roller skiing, when using the diagonal stride and kick double poling techniques. The study used ratcheted wheel roller skis from the open market and a uniquely designed roller ski with an adjustable camber and grip function. The results showed significantly (P ≤ 0.05) higher oxygen consumption (∼ 14%), heart rate (∼ 7%), and lower propulsive forces from the legs during submaximal exercise and a shorter time to exhaustion (∼ 30%) in incremental maximal tests when using roller skis with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a similar, higher μS. Thus, we concluded that oxygen consumption (skiing economy), propulsive leg forces, and performance time are highly changed for the worse when using roller skis with a lower μS, such as for on-snow skiing with grip-waxed cross-country skis, in comparison to ratcheted wheel roller skis with several times higher μS. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Natural hazards in the Alps triggered by ski slope engineering and artificial snow production

NASA Astrophysics Data System (ADS)

de Jong, C.

2012-04-01

In the Alps there is increasing concern of man-made triggering of natural hazards in association with ski slope engineering and pressures from climate change. However literature on the topic is rare. Ski run development has been intensified in the past decade to accommodate a higher density of skiers. In order to absorb the increased flux of skiers promoted by continually increasing lift capacity, ski runs are subject to more and more enlargement, straightening and leveling. This has required large-scale re-leveling of slopes with the removal of soil and protective vegetation using heavy machinery during the summer season. Slope-ward incision on steep slopes, creation of artificial embankments by leeward deposition and development of straight ski runs perpendicular to steep slopes have resulted in both shallow and deep erosion, gullying, triggering of small landslides and even bedload transport in marginal channels. Other natural hazards have been triggered directly or indirectly due to intensification of artificial snow production. This has increased exponentially in the last decade in order to secure the skiing season under increasingly warm temperatures and erratic snowfall and decreasing snow depth and snow duration in association with climate change. The consequences are multiple. Firstly, in order to economize both costs and quantity of artificial snow production, ski runs are leveled as far as possible in order to avoid topographical irregularities, protruding vegetation or rocks. The combination of topsoil removal and prolonged duration of artificial snow cover results in a decreased vegetation cover and period as well as species alteration. Together with greatly decreased permeability of the underground, snowmelt and intensive summer precipitation trigger surface runoff, erosion and even small landslides. After more than a decade of intensive cover by artificial snow, most such steep ski runs at altitudes above 1400 m are reduced into highly erosive, vegetation-poor scree slopes in summertime. Secondly, the production of artificial snow requires increasingly large quantities of water during low flow periods and causes an exponential increase in the construction of water reservoirs and pipelines. Such reservoirs are often constructed in depressions occupied by wetlands but also on slopes, hilltops and in proglacial locations at high altitudes up to 3000m. Reservoir construction removes vegetation, soil and regolith over surface areas of up to 150 000 m2 and depths of more than 20 m. During their construction, the temporary or permanent storage of large quantities of sediment on steep slopes has lead in several cases to the production of debris flows. Each reservoir requires road construction and vehicle parking areas for heavy weight vehicle access. These are frequently subject to erosion, gullying, and small landslides. Some reservoirs are vulnerable to catastrophic drainage triggered by earthquakes, avalanches and other natural hazards typical for mountain environments since they are only sealed with plastic membranes. Thirdly, the melt of artificial snow introduced by water transfers from other catchments can cause a relatively large local surplus of water which in turn increases spring and summer flood peaks as well as sediment transport. Most steep ski runs have introduced artificial drainage canals across the ski runs to avoid concentration of surface flow and to prevent erosion. Slopes are also covered with organic soils and re-vegetated where possible. However, given the present trends of intensification of use and precipitation extremes, it is unlikely that erosion and mass movements can be prevented in the next few decades for the duration of the amortization of investments.

Hypsometry and the distribution of high-alpine lakes in the European Alps

NASA Astrophysics Data System (ADS)

Prasicek, Günther; Otto, Jan-Christoph; Buckel, Johannes; Keuschnig, Markus

2017-04-01

Climate change strongly affects alpine landscapes. Cold-climate processes shape the terrain in a typical way and ice-free overdeepenings in cirques and glacial valleys as well as different types of moraines favor the formation of lakes. These water bodies act as sediment sinks and high-alpine water storage but may also favor outburst and flooding events. Glacier retreat worldwide is associated with an increasing number and size of high-alpine lakes which implies a concurrent expansion of sediment retention and natural hazard potential. Rising temperatures are regarded to be the major cause for this development, but other factors such as the distribution of area over elevation and glacier erosional and depositional dynamics may play an important role as well. While models of ice flow and glacial erosion are employed to understand the impact of glaciers on mountain landscapes, comprehensive datasets and analyses on the distribution of existing high-alpine lakes are lacking. In this study we present an exhaustive database of natural lakes in the European Alps and analyze lake distribution with respect to hypsometry. We find that the distribution of lake number and lake area over elevation only weakly coincides with hypsometry. Unsurprisingly, largest lakes are often tectonically influenced and located at the fringe of the mountain range and in prominent inter-montane basins. With increasing elevation, however, the number of lakes, lake area and total area decrease until a local minimum is reached around the equilibrium line latitude (ELA) of the last glacial maximum (LGM). Above the LGM ELA, total area further decreases, but lake number and area increase again. A local maximum in lake area coincides with an absolute maximum in lake number between the ELAs of the LGM and the little ice age around 2500 m. We conclude that glacial erosional and depositional dynamics control the distribution and size of high-alpine lakes and thus demand for exceptional attention when predicting future lake development.

Eccentric exercise: mechanisms and effects when used as training regime or training adjunct.

PubMed

Vogt, Michael; Hoppeler, Hans H

2014-06-01

The aim of the current review is to discuss applications and mechanism of eccentric exercise in training regimes of competitive sports. Eccentric muscle work is important in most sports. Eccentric muscle contractions enhance the performance during the concentric phase of stretch-shortening cycles, which is important in disciplines like sprinting, jumping, throwing, and running. Muscles activated during lengthening movements can also function as shock absorbers, to decelerate during landing tasks or to precisely deal with high external loading in sports like alpine skiing. The few studies available on trained subjects reveal that eccentric training can further enhance maximal muscle strength and power. It can further optimize muscle length for maximal tension development at a greater degree of extension, and has potential to improve muscle coordination during eccentric tasks. In skeletal muscles, these functional adaptations are based on increases in muscle mass, fascicle length, number of sarcomeres, and cross-sectional area of type II fibers. Identified modalities for eccentric loading in athletic populations involve classical isotonic exercises, accentuated jumping exercises, eccentric overloading exercises, and eccentric cycle ergometry. We conclude that eccentric exercise offers a promising training modality to enhance performance and to prevent injuries in athletes. However, further research is necessary to better understand how the neuromuscular system adapts to eccentric loading in athletes. Copyright © 2014 the American Physiological Society.

The economic aspects of artificial snow production in the perspective of climate change

NASA Astrophysics Data System (ADS)

Gonseth, C.

2012-04-01

Snowmaking is now used by ski resorts worldwide as a measure to cope with both natural snow reduction and variability. This extensive recourse casts doubt on its sustainability mainly because of the large amount of natural resources being used (energy, water). In the middle to long run, this problem is expected to increase with future climate change triggering the production of more snow. The research field that focuses on the economic aspects of artificial snow production is still in its infancy but potentially covers a wide array of issues. Among these issues, benefits and costs of snowmaking are important ones. On the one hand, benefits arise as snowmaking extends or preserves the operating period of ski areas. Several empirical studies speculate or show that snowmaking considerably reduces the sensitivity of tourism consumption to variations in snow conditions. These benefits have long been neglected in studies analyzing the consequences of climate change for the winter tourism sector. While failing to introduce these benefits, many studies have generated overly high costs of climate change. On the other hand, investments and operating costs of artificial snow production depend upon several factors, such as technology and local conditions. Consequently, costs vary considerably from one location to another and over time, yet indicative values can be found in the literature. In addition, artificial snow production generates external costs, i.e. costs that are not born by those producing it. Typical of these external costs are environmental ones that are related to CO2 emissions or biodiversity losses. To our knowledge, very little has been done so far to integrate these costs in economic studies. To the extent that vertical integration is absent, it may happen as well that snow production generates important external benefits for different stakeholders at a given ski resort. From an economic point of view, both types of externalities could lead to investment levels that are not optimal in the sense that they do not maximize social welfare. More generally, economic analysis has the potential to explain current investment and snow production levels and to determine optimal ones. It can also predict the evolution of these levels under a warmer climate. For instance, such predictions were carried out for Switzerland as well as for other Alpine countries using a computable general equilibrium model of the world economy with a time horizon up to 2050, the GEMINI-E3 model. With all these points in mind, this presentation aims at reviewing what has been done so far on the economic aspects of artificial snow production and also at identifying avenues for future research.

Flight style optimization in ski jumping on normal, large, and ski flying hills.

PubMed

Jung, Alexander; Staat, Manfred; Müller, Wolfram

2014-02-07

In V-style ski jumping, aerodynamic forces are predominant performance factors and athletes have to solve difficult optimization problems in parts of a second in order to obtain their jump length maximum and to keep the flight stable. Here, a comprehensive set of wind tunnel data was used for optimization studies based on Pontryagin's minimum principle with both the angle of attack α and the body-ski angle β as controls. Various combinations of the constraints αmax and βmin(t) were analyzed in order to compare different optimization strategies. For the computer simulation studies, the Olympic hill profiles in Esto-Sadok, Russia (HS 106m, HS 140m), and in Harrachov, Czech Republic, host of the Ski Flying World Championships 2014 (HS 205m) were used. It is of high importance for ski jumping practice that various aerodynamic strategies, i.e. combinations of α- and β-time courses, can lead to similar jump lengths which enables athletes to win competitions using individual aerodynamic strategies. Optimization results also show that aerodynamic behavior has to be different at different hill sizes (HS). Optimized time courses of α and β using reduced drag and lift areas in order to mimic recent equipment regulations differed only in a negligible way. This indicates that optimization results presented here are not very sensitive to minor changes of the aerodynamic equipment features when similar jump length are obtained by using adequately higher in-run velocities. However, wind tunnel measurements with athletes including take-off and transition to stabilized flight, flight, and landing behavior would enable a more detailed understanding of individual flight style optimization. © 2013 Published by Elsevier Ltd.

Development of land use regression models for nitrogen dioxide, ultrafine particles, lung deposited surface area, and four other markers of particulate matter pollution in the Swiss SAPALDIA regions.

PubMed

Eeftens, Marloes; Meier, Reto; Schindler, Christian; Aguilera, Inmaculada; Phuleria, Harish; Ineichen, Alex; Davey, Mark; Ducret-Stich, Regina; Keidel, Dirk; Probst-Hensch, Nicole; Künzli, Nino; Tsai, Ming-Yi

2016-04-18

Land Use Regression (LUR) is a popular method to explain and predict spatial contrasts in air pollution concentrations, but LUR models for ultrafine particles, such as particle number concentration (PNC) are especially scarce. Moreover, no models have been previously presented for the lung deposited surface area (LDSA) of ultrafine particles. The additional value of ultrafine particle metrics has not been well investigated due to lack of exposure measurements and models. Air pollution measurements were performed in 2011 and 2012 in the eight areas of the Swiss SAPALDIA study at up to 40 sites per area for NO2 and at 20 sites in four areas for markers of particulate air pollution. We developed multi-area LUR models for biannual average concentrations of PM2.5, PM2.5 absorbance, PM10, PMcoarse, PNC and LDSA, as well as alpine, non-alpine and study area specific models for NO2, using predictor variables which were available at a national level. Models were validated using leave-one-out cross-validation, as well as independent external validation with routine monitoring data. Model explained variance (R(2)) was moderate for the various PM mass fractions PM2.5 (0.57), PM10 (0.63) and PMcoarse (0.45), and was high for PM2.5 absorbance (0.81), PNC (0.87) and LDSA (0.91). Study-area specific LUR models for NO2 (R(2) range 0.52-0.89) outperformed combined-area alpine (R (2)  = 0.53) and non-alpine (R (2)  = 0.65) models in terms of both cross-validation and independent external validation, and were better able to account for between-area variability. Predictor variables related to traffic and national dispersion model estimates were important predictors. LUR models for all pollutants captured spatial variability of long-term average concentrations, performed adequately in validation, and could be successfully applied to the SAPALDIA cohort. Dispersion model predictions or area indicators served well to capture the between area variance. For NO2, applying study-area specific models was preferable over applying combined-area alpine/non-alpine models. Correlations between pollutants were higher in the model predictions than in the measurements, so it will remain challenging to disentangle their health effects.

Vulnerability assessment of skiing-dependent businesses to the effects of climate change in Banff and Jasper National Parks, Canada

NASA Astrophysics Data System (ADS)

Reynolds, David Michael

This qualitative study examines the potential positive and negative socio-economic impacts that may emerge from the long-term effects of climate change on skiing-dependent businesses in Banff and Jasper National Parks, Canada. My goal was to determine whether or not skiing-related tourism in the parks in the 2020s and 2050s is more or less socio-economically vulnerable to the effects of climate change on snow cover, temperatures and ski season length at ski resorts in the parks. My study explored the level of awareness and personal perceptions of 60 skiing-dependent business managers about how the impact of climate change on ski resorts may influence future socio-economics of ski tourism businesses. I employed a vulnerability assessment approach and adopted some elements of grounded theory. My primary data sources are interviews with managers and the outcome of the geographical factors index (GFI). Supporting methods include: an analysis and interpretation of climate model data and an interpretation of the economic analysis of skiing in the parks. The interview data were sorted and coded to establish concepts and findings by interview questions, while the GFI model rated and ranked 24 regional ski resorts in the Canadian Cordillera. The findings answered the research questions and helped me conclude what the future socio-economic vulnerability may be of skiing-dependent businesses in the parks. The interviews revealed that managers are not informed about climate change and they have not seen any urgency to consider the effects on business. The GFI revealed that the ski resorts in the parks ranked in the top ten of 24 ski resorts in the Cordillera based on 14 common geographical factors. The economic reports suggest skiing is the foundation of the winter economy in the parks and any impact on skiing would directly impact other skiing-dependent businesses. Research indicates that the effects of climate change may have less economic impact on skiing-dependent businesses in Banff and Jasper in the 2020s and 2050s compared with other ski resorts located in the Cordillera. Recommendations are provided to explore future research opportunities and for skiing-dependent businesses and government organizations.

SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Li; Weng, Wei; Sun, Zhi-Xin

Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, andmore » concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice.« less

Skiing trends

Treesearch

Charles R. Goeldner; Stacy Standley

1980-01-01

A brief historical overview of skiing is presented, followed by a review of factors such as energy, population trends, income, sex, occupation and attitudes which affect the future of skiing. A. C. Neilson's Sports Participation Surveys show that skiing is the second fastest growing sport in the country. Skiing Magazine's study indicates there are...

Ski can negatively regulates macrophage differentiation through its interaction with PU.1

PubMed Central

Ueki, N; Zhang, L; Haymann, MJ

2010-01-01

In the hematopoietic cell system, the oncoprotein Ski dramatically affects growth and differentiation programs, in some cases leading to malignant leukemia. However, little is known about the interaction partners or signaling pathways involved in the Ski-mediated block of differentiation in hematopoietic cells. Here we show that Ski interacts with PU.1, a lineage-specific transcription factor essential for terminal myeloid differentiation, and thereby represses PU.1-dependent transcriptional activation. Consistent with this, Ski inhibits the biological function of PU.1 to promote myeloid cells to differentiate into macrophage colony-stimulating factor receptor (M-CSFR)-positive macrophages. Using a Ski mutant deficient in PU.1 binding, we demonstrate that Ski–PU.1 interaction is critical for Ski's ability to repress PU.1-dependent transcription and block macrophage differentiation. Furthermore, we provide evidence that Ski-mediated repression of PU.1 is due to Ski's ability to recruit histone deacetylase 3 to PU.1 bound to DNA. Since inactivation of PU.1 is closely related to the development of myeloid leukemia and Ski strongly inhibits PU.1 function, we propose that aberrant Ski expression in certain types of myeloid cell lineages might contribute to leukemogenesis. PMID:17621263

Analysis and Comparison of the Temperature and Snowfall Conditions for the Winters of 2014/15 and 2015/16 at Three Ski Resorts in British Columbia, Canada

NASA Astrophysics Data System (ADS)

Pidwirny, M. J.; Pedersen, S.

2016-12-01

Most ski resorts located close to the west coast of Canada experienced extremely poor weather conditions during the winter of 2014/15. During this year, a persistent area of high pressure created "the Blob" in the North Pacific Ocean, which influenced weather patterns on the west coast of North America producing very mild temperatures inland. Further, for many ski resorts winter precipitation that normally arrives in the form of snow, instead fell as rain on many occasions. In Western Canada, ski resorts saw an 18% decrease in skier visits in 2014/15 relative to the average of the previous 8 years. NOAA forecasts for the winter of 2015/16 suggested another mild winter because of a strong El Nino event. Despite this forecast, ski resorts in Western Canada experienced a very good ski season. This research examines the climate characteristics of the winters of 2014/15 and 2015/16 in detail for three ski resorts in British Columbia, Canada: Whistler-Blackcomb, Cypress Mountain, and Big White. The climatic characteristics of these 2 years were also compared to the winter of 2012/13, the most recent banner ski year in the last decade. Data for this study came from Snow-Forecast.com, a web-based company that creates tailor-made weather forecasts for ski resorts around the world using climate model output from NOAA. From Snow-Forecast.com, we mined archived hindcast data that was available at the daily level to analyze and compare mean air temperature and snowfall patterns from November 1 to March 31. Daily temperature data was plotted in a line graph for each year. To better clarify trends, we also graphed an 11-year running mean for the temperature data. Snowfall data was plotted in a cumulative line graph. The winter of 2014/15 was on average warmer by 3.9°C for Cypress, 5.4°C for Whistler, and 4.4°C for Big White than the winter of 2012/13. The winter of 2015/16 was on average 2.5°C, 3.6°C, and 3.6°C warmer than the winter of 2012/13, respectively. Snowfall accumulations decreased by about 79% for Cypress, 57% for Whistler, and 9% for Big White in 2014/15 when compared to 2012/13. In contrast, the winter of 2015/16 saw snowfall increases of 10% for Cypress, 35% for Whistler, and 97% for Big White relative to 2012/13. Together, the colder temperatures and higher snowfall produced better than expected ski conditions in 2015/16.

Is phytoremediation a sustainable and reliable approach to clean-up contaminated water and soil in Alpine areas?

PubMed

Schwitzguébel, Jean-Paul; Comino, Elena; Plata, Nadia; Khalvati, Mohammadali

2011-07-01

Phytoremediation does exploit natural plant physiological processes and can be used to decontaminate agricultural soils, industrial sites, brownfields, sediments and water containing inorganic and organic pollutants or to improve food chain safety by phytostabilisation of toxic elements. It is a low-cost and environment friendly technology targetting removal, degradation or immobilisation of contaminants. The aim of the present review is to highlight some recent advances in phytoremediation in the Alpine context. Case studies are presented where phytoremediation has been or can be successfully applied in Alpine areas to: (1) clean-up industrial wastewater containing sulphonated aromatic xenobiotics released by dye and textile industries; (2) remediate agricultural soils polluted by petroleum hydrocarbons; (3) improve food chain safety in soils contaminated with toxic trace elements (As, Co, Cr and Pb); and (4) treat soils impacted by modern agricultural activities with a special emphasis on phosphate fertilisation. Worlwide, including in Alpine areas, the controlled use of appropriate plants is destined to play a major role for remediation and restoration of polluted and degraded ecosystems, monitoring and assessment of environmental quality, prevention of landscape degradation and immobilisation of trace elements. Phytotechnologies do already offer promising approaches towards environmental remediation, human health, food safety and sustainable development for the 21st century in Alpine areas and elsewhere all over the world.

[Snow trauma: comparison between skiers and snowboarders].

PubMed

Gigli Berzolari, Francesca; Marchetti, Pierpaolo; Mancini, Matteo

2009-01-01

skiing is practiced by million of persons every year, while snowboard is an emerging sport. This study compares the types of injury produced by the two sports. an observational study based on current data concerning traumas in skiing and snowboard. 1,264 skiers and 228 snowboarders injured were studied. Student's t test and chi-square test, logistic regression. snow injuries occurring in the ski resorts of agordino (Belluno), Arabba-Marmolada, Alleghe and Falcade between December 2006 and April 2007. Data were collected from the database of the Agordo Public Hospital, of the 118 Emergency service of Pieve di Cadore, and of several ski resorts. age, sex, country area, kind of injury, numbers, severity and type of trauma, injury time, prognosis, part of the body injured. the two sports differ with regard to trauma types: sprains and distortions are more frequent in skiers, whereas fractures (breaks) are more frequent in the snowboard. Lower limbs (knee) in ski and upper limbs (wrist) in snowboard are the main lesion sites. With regard to the ankle's injuries, no difference was found between the two sport: this contrasts with previous findings reported in the literature. Severity of trauma is not related to the kind of sport. the results of the present study agree with previous findings with regard to the type of lesions observed in the two sports. Among snowboarders, it is possible that recent materials and equipments reduce ankle injury risk. In spite of the differences in equipment and gestures, the consequences of injury are similar in the two sports.

ALPINE LAKES WILDERNESS STUDY AREA, WASHINGTON.

USGS Publications Warehouse

Gualtieri, J.L.; Thurber, H.K.

1984-01-01

The Alpine Lakes Wilderness study area, located in the central part of the Cascade Mountains of Washington was examined for its mineral-resource potential. On the basis of that study the area was found to contain deposits of copper, other base metals, and gold and silver. Probable or substantiated mineral-resource potential exists for these commodities in the southwest-central, northwest, and southeast-central parts of the area. The geologic terrane precludes the occurrence of fossil fuel resources.

Characterization of chicken c-ski oncogene products expressed by retrovirus vectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sutrave, P.; Copeland, T.D.; Hughes, S.H.

1990-06-01

The authors have constructed replication-competent avian retrovirus vectors that contain two of the three known types of chicken c-{ital ski} cDNAs and a third vector that contains a truncated c-{ital ski} cDNA. They developed antisera that recognize the c-{ital ski} proteins made by the three transforming c-{ital ski} viruses. All three proteins (apparent molecular masses, 50, 60, and 90 kilodaltons) are localized primarily in the nucleus. The proteins are differentially phosphorylated; immunofluorescence also suggests that there are differences in subnuclear localization of the c-{ital ski} proteins and that c-{ital ski} protein is associated with condensed chromatin in dividing cells.

36 CFR 7.62 - Lake Chelan National Recreation Area.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and depending on local weather conditions, the superintendent may designate as open to the use of snowmobiles the following locations within the Lake Chelan National Recreation Area: (1) All open areas..., except cross-country ski trails and within the perimeter of the Buckner Orchard. Snowmobile use on open...

Direct interaction of Ski with either Smad3 or Smad4 is necessary and sufficient for Ski-mediated repression of transforming growth factor-beta signaling.

PubMed

Ueki, Nobuhide; Hayman, Michael J

2003-08-29

The oncoprotein Ski represses transforming growth factor (TGF)-beta signaling in an N-CoR-independent manner. However, the molecular mechanism(s) underlying this event has not been elucidated. Here, we identify an additional domain in Ski that mediates interaction with Smad3 which is important for this repression. This domain is distinct from the previously reported N-terminal Smad3 binding domain in Ski. Individual alanine substitution of several residues in the domain significantly affected Ski-Smad3 interaction. Furthermore, combined mutations within this domain, together with those in the previously identified Smad3 binding domain, can completely abolish the interaction of Ski with Smad3, while mutation in each domain alone retained partial interaction. By introducing those mutations that abolish direct interaction with Smad3 or Smad4 individually, or in combination, we show that interaction of Ski with either Smad3 or Smad4 is sufficient for Ski-mediated repression of TGF-beta signaling. Furthermore our results clearly demonstrate that Ski does not disrupt Smad3-Smad4 heteromer formation, and recruitment of Ski to the Smad3/4 complex through binding to either Smad3 or Smad4 is both necessary and sufficient for repression.

Biomechanical comparison of the double-push technique and the conventional skate skiing technique in cross-country sprint skiing.

PubMed

Stöggl, Thomas; Müller, Erich; Lindinger, Stefan

2008-09-01

The aims of the study were to: (1) adapt the "double-push" technique from inline skating to cross-country skiing; (2) compare this new skiing technique with the conventional skate skiing cross-country technique; and (3) test the hypothesis that the double-push technique improves skiing speed in a short sprint. 13 elite skiers performed maximum-speed sprints over 100 m using the double-push skate skiing technique and using the conventional "V2" skate skiing technique. Pole and plantar forces, knee angle, cycle characteristics, and electromyography of nine lower body muscles were analysed. We found that the double-push technique could be successfully transferred to cross-country skiing, and that this new technique is faster than the conventional skate skiing technique. The double-push technique was 2.9 +/- 2.2% faster (P < 0.001), which corresponds to a time advantage of 0.41 +/- 0.31 s over 100 m. The double-push technique had a longer cycle length and a lower cycle rate, and it was characterized by higher muscle activity, higher knee extension amplitudes and velocities, and higher peak foot forces, especially in the first phase of the push-off. Also, the foot was more loaded laterally in the double-push technique than in the conventional skate skiing technique.

c-Ski inhibits the TGF-beta signaling pathway through stabilization of inactive Smad complexes on Smad-binding elements.

PubMed

Suzuki, Hiroyuki; Yagi, Ken; Kondo, Miki; Kato, Mitsuyasu; Miyazono, Kohei; Miyazawa, Keiji

2004-06-24

c-Ski inhibits transforming growth factor-beta (TGF-beta) signaling through interaction with Smad proteins. c-Ski represses Smad-mediated transcriptional activation, probably through its action as a transcriptional co-repressor. c-Ski also inhibits TGF-beta-induced downregulation of genes such as c-myc. However, mechanisms for transcriptional regulation of target genes by c-Ski have not been fully determined. In this study, we examined how c-Ski inhibits both TGF-beta-induced transcriptional activation and repression. DNA-affinity precipitation analysis revealed that c-Ski enhances the binding of Smad2 and 4, and to a lesser extent Smad3, to both CAGA and TGF-beta1 inhibitory element probes. A c-Ski mutant, which is unable to interact with Smad4, failed to enhance the binding of Smad complex on these probes and to inhibit the Smad-responsive promoter. These results suggest that stabilization of inactive Smad complexes on DNA is a critical event in c-Ski-mediated inhibition of TGF-beta signaling.

Novel Regulation of Ski Protein Stability and Endosomal Sorting by Actin Cytoskeleton Dynamics in Hepatocytes*

PubMed Central

Vázquez-Victorio, Genaro; Caligaris, Cassandre; Del Valle-Espinosa, Eugenio; Sosa-Garrocho, Marcela; González-Arenas, Nelly R.; Reyes-Cruz, Guadalupe; Briones-Orta, Marco A.; Macías-Silva, Marina

2015-01-01

TGF-β-induced antimitotic signals are highly regulated during cell proliferation under normal and pathological conditions, such as liver regeneration and cancer. Up-regulation of the transcriptional cofactors Ski and SnoN during liver regeneration may favor hepatocyte proliferation by inhibiting TGF-β signals. In this study, we found a novel mechanism that regulates Ski protein stability through TGF-β and G protein-coupled receptor (GPCR) signaling. Ski protein is distributed between the nucleus and cytoplasm of normal hepatocytes, and the molecular mechanisms controlling Ski protein stability involve the participation of actin cytoskeleton dynamics. Cytoplasmic Ski is partially associated with actin and localized in cholesterol-rich vesicles. Ski protein stability is decreased by TGF-β/Smads, GPCR/Rho signals, and actin polymerization, whereas GPCR/cAMP signals and actin depolymerization promote Ski protein stability. In conclusion, TGF-β and GPCR signals differentially regulate Ski protein stability and sorting in hepatocytes, and this cross-talk may occur during liver regeneration. PMID:25561741

Physics and Skiing.

ERIC Educational Resources Information Center

Swinson, Derek B.

1992-01-01

Presents examples of physics as applied to the sport of skiing. Examples examine the physics of sliding, unweighting, ski turning, wind resistance, the parabolic and circular motion of aerial skiers, and the aerial maneuvers of ski jumpers. (MDH)

Ski acts as a co-repressor with Smad2 and Smad3 to regulate the response to type β transforming growth factor

PubMed Central

Xu, Weidong; Angelis, Konstantina; Danielpour, David; Haddad, Maher M.; Bischof, Oliver; Campisi, Judith; Stavnezer, Ed; Medrano, Estela E.

2000-01-01

The c-ski protooncogene encodes a transcription factor that binds DNA only in association with other proteins. To identify co-binding proteins, we performed a yeast two-hybrid screen. The results of the screen and subsequent co-immunoprecipitation studies identified Smad2 and Smad3, two transcriptional activators that mediate the type β transforming growth factor (TGF-β) response, as Ski-interacting proteins. In Ski-transformed cells, all of the Ski protein was found in Smad3-containing complexes that accumulated in the nucleus in the absence of added TGF-β. DNA binding assays showed that Ski, Smad2, Smad3, and Smad4 form a complex with the Smad/Ski binding element GTCTAGAC (SBE). Ski repressed TGF-β-induced expression of 3TP-Lux, the natural plasminogen activator inhibitor 1 promoter and of reporter genes driven by the SBE and the related CAGA element. In addition, Ski repressed a TGF-β-inducible promoter containing AP-1 (TRE) elements activated by a combination of Smads, Fos, and/or Jun proteins. Ski also repressed synergistic activation of promoters by combinations of Smad proteins but failed to repress in the absence of Smad4. Thus, Ski acts in opposition to TGF-β-induced transcriptional activation by functioning as a Smad-dependent co-repressor. The biological relevance of this transcriptional repression was established by showing that overexpression of Ski abolished TGF-β-mediated growth inhibition in a prostate-derived epithelial cell line. PMID:10811875

Ski acts as a co-repressor with Smad2 and Smad3 to regulate the response to type beta transforming growth factor.

PubMed

Xu, W; Angelis, K; Danielpour, D; Haddad, M M; Bischof, O; Campisi, J; Stavnezer, E; Medrano, E E

2000-05-23

The c-ski protooncogene encodes a transcription factor that binds DNA only in association with other proteins. To identify co-binding proteins, we performed a yeast two-hybrid screen. The results of the screen and subsequent co-immunoprecipitation studies identified Smad2 and Smad3, two transcriptional activators that mediate the type beta transforming growth factor (TGF-beta) response, as Ski-interacting proteins. In Ski-transformed cells, all of the Ski protein was found in Smad3-containing complexes that accumulated in the nucleus in the absence of added TGF-beta. DNA binding assays showed that Ski, Smad2, Smad3, and Smad4 form a complex with the Smad/Ski binding element GTCTAGAC (SBE). Ski repressed TGF-beta-induced expression of 3TP-Lux, the natural plasminogen activator inhibitor 1 promoter and of reporter genes driven by the SBE and the related CAGA element. In addition, Ski repressed a TGF-beta-inducible promoter containing AP-1 (TRE) elements activated by a combination of Smads, Fos, and/or Jun proteins. Ski also repressed synergistic activation of promoters by combinations of Smad proteins but failed to repress in the absence of Smad4. Thus, Ski acts in opposition to TGF-beta-induced transcriptional activation by functioning as a Smad-dependent co-repressor. The biological relevance of this transcriptional repression was established by showing that overexpression of Ski abolished TGF-beta-mediated growth inhibition in a prostate-derived epithelial cell line.

Tank Investigation of the EDO Model 142 Hydro-Ski Research Airplane

NASA Technical Reports Server (NTRS)

Ramsen, John A.; Wadlin, Kenneth L.; Gray, George R.

1951-01-01

A tank investigation has been conducted of a 1/10-size powered-dynamic model of the Edo model 142 hydra-ski research airplane. The results of tests of two configurations are presented: One included a large ski and a ski well; the other, a small ski without a well. Water take-offs would be possible with the available thrust for either configuration: however, the configuration with the large ski emerged sooner and had less resistance from ski emergence until take-off. Longitudinal stability and landing behavior in smooth water were satisfactory for both configurations. Some alteration to the design of the tail would be desirable in order to reduce the spray loads.

Numerical investigation of the early flight phase in ski-jumping.

PubMed

Gardan, N; Schneider, A; Polidori, G; Trenchard, H; Seigneur, J M; Beaumont, F; Fourchet, F; Taiar, R

2017-07-05

The purpose of this study is to develop a numerical methodology based on real data from wind tunnel experiments to investigate the effect of the ski jumper's posture and speed on aerodynamic forces in a wide range of angles of attack. To improve our knowledge of the aerodynamic behavior of the ski jumper and his equipment during the early flight phase of the ski jump, we applied CFD methodology to evaluate the influence of angle of attack (α=14°, 21.5°, 29°, 36.5° and 44°) and speed (u=23, 26 and 29m/s) on aerodynamic forces in the situation of stable attitude of the ski jumper's body and skis. The standard k-ω turbulence model was used to investigate both the influence of the ski jumper's posture and speed on aerodynamic performance during the early flight phase. Numerical results show that the ski jumper's speed has very little impact on the lift and drag coefficients. Conversely, the lift and drag forces acting on the ski jumper's body during the early flight phase of the jump are strongly influenced by the variations of the angle of attack. The present results suggest that the greater the ski jumper's angle of inclination, with respect to the relative flow, the greater the pressure difference between the lower and upper parts of the skier. Further studies will focus on the dependency of the parameters with both the angle of attack α and the body-ski angle β as control variables. It will be possible to test and optimize different ski jumping styles in different ski jumping hills and investigate different environmental conditions such as temperature, altitude or crosswinds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of SKI2670, a novel, orally active, non-peptide GnRH antagonist, on hypothalamic-pituitary-gonadal axis.

PubMed

Kim, Seon Mi; Yoo, Taekyung; Lee, So Young; Kim, Eun Jeong; Lee, Soo Min; Lee, Min Hee; Han, Min Young; Jung, Seung-Hyun; Choi, Jung-Hye; Ryu, Keun Ho; Kim, Hun-Taek

2015-10-15

Suppression of the hypothalamic-pituitary-gonadal axis has been widely utilized for the management of gonadal-hormone-dependent diseases such as endometriosis. Efforts to develop orally available gonadotropin-releasing hormone (GnRH) antagonists for the treatment of gonadal-hormone-dependent diseases led to the discovery of SKI2670, a novel non-peptide GnRH antagonist. The present study was undertaken to pharmacologically characterize SKI2670 in vitro and in vivo. We measured binding affinity and antagonistic activity of SKI2670 for the GnRH receptors. Immediate suppression of gonadotropins by single dosing of SKI2670 was examined in castrated monkeys. Subsequently, influence on gonadal hormones by prolonged administration of SKI2670 was assessed in naive female monkeys. To investigate in vivo efficacy of SKI2670, regression of ectopic implants by repeated administration of SKI2670 was examined in a rat endometriosis model. SKI2670 is a potent functional antagonist for the human GnRH receptor, with subnanomolar binding affinity. In castrated monkeys, single administration of SKI2670 lowered serum luteinizing hormone (LH) levels stronger with longer duration when compared to elagolix at equivalent doses. Moreover, repeated dosing of SKI2670 suppressed serum levels of gonadotropins and gonadal hormones in intact female monkeys while elagolix suppressed serum LH levels only. Finally, it exhibited regressive effects on ectopic implants in a rat endometriosis model without bone loss. Our findings demonstrate robust GnRH antagonistic efficacy of SKI2670 in animal models, suggesting that SKI2670-induced suppression of the hypothalamic-pituitary-gonadal axis may be beneficial for the treatment of gonadal-hormone-dependent diseases such as endometriosis in humans. Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical exposure among professional ski waxers--characterization of individual work operations.

PubMed

Freberg, Baard Ingegerdsson; Olsen, Raymond; Thorud, Syvert; Ellingsen, Dag G; Daae, Hanne Line; Hersson, Merete; Molander, Paal

2013-04-01

Preparation of skis prior to skiing competitions involves several individual work operations and the use of a wide variety of chemically based ski waxing products to improve the performance of the skis, including products used after skiing for wax removal and ski sole cleaning. Modern ski waxes consist mainly of petroleum-derived straight-chain aliphatic hydrocarbons, perfluoro-n-alkanes or polyfluorinated n-alkanes. The wax cleaning products contain solvents such as neat aliphatic hydrocarbons (aliphates) or a mixture with limonene. Different ski waxing work operations can result in contaminated workroom atmospheres. The aim of this study was to assess the chemical exposures related to the individual ski waxing work operations by investigating the specific work operations in controlled model experiments. Four main work operations with potential exposures were identified: (i) application of glider waxes, (ii) scraping and brushing of applied glider waxes, (iii) application of base/grip waxes, and (iv) ski sole cleaning. Aerosol particle masses were sampled using conical samplers equipped with 37-mm PVC, 5-µm pore size filters and cyclones equipped with 37-mm PVC, 0.8-µm pore size filters for the inhalable and the respirable aerosol mass fractions, respectively. For measurements of particle number concentrations, a Scanning Mobility Particle Sizer was used. Mean aerosol particle mass concentrations of 18.6 mg m(-3) and 32.2 mg m(-3) were measured during application of glider wax powders in the respirable and in the inhalable aerosol mass fractions, respectively. Particle number concentration of ~900 000 particles cm(-3) was measured during application of glider wax powder products. Ski sole cleaning with products containing aliphates displayed solvent air concentrations up to 62.5 p.p.m. This study shows that the potential exposure to generated particles during ski waxing and ski preparation is considerable, especially during work using glide wax powders.

Structural mechanism of Smad4 recognition by the nuclear oncoprotein Ski: insights on Ski-mediated repression of TGF-beta signaling.

PubMed

Wu, Jia Wei; Krawitz, Ariel R; Chai, Jijie; Li, Wenyu; Zhang, Fangjiu; Luo, Kunxin; Shi, Yigong

2002-11-01

The Ski family of nuclear oncoproteins represses TGF-beta signaling through interactions with the Smad proteins. The crystal structure of the Smad4 binding domain of human c-Ski in complex with the MH2 domain of Smad4 reveals specific recognition of the Smad4 L3 loop region by a highly conserved interaction loop (I loop) from Ski. The Ski binding surface on Smad4 significantly overlaps with that required for binding of the R-Smads. Indeed, Ski disrupts the formation of a functional complex between the Co- and R-Smads, explaining how it could lead to repression of TGF-beta, activin, and BMP responses. Intriguingly, the structure of the Ski fragment, stabilized by a bound zinc atom, resembles the SAND domain, in which the corresponding I loop is responsible for DNA binding.

[Ski and SnoN: antagonistic proteins of TGFbeta signaling].

PubMed

Vignais, M L

2000-02-01

Ski and SnoN are two proto-oncogenes that, at high cellular concentrations, are associated with tumors. Up to now, apart the fact that SnoN and Ski were known to bind to DNA indirectly, very little was known about the mechanism which enables these factors to induce tumorigenesis. We know now that SnoN and Ski interact with the SMAD proteins which are mediators of TGFbeta signaling. These SMADs enable recruitment to target gene promoters of SnoN and Ski as well as the histone deacetylase activity which is associated with them. Whereas physiologic concentrations of SnoN and Ski allow a feedback regulation of TGFbeta signaling, deregulation of SnoN or Ski expression leads to total inhibition of TGFbeta signaling and of the tumor suppressors Smad2 and Smad4, which can explain the role of SnoN and Ski as oncogenes.

Sub-alpine amphibian distributions related to species palatability to non-native salmonids in the Klamath mountains of northern California

Treesearch

Hartwell H. Welsh Jr; Karen L. Pope; Daniel Boiano

2006-01-01

The goal of this study was to examine how introduced trout influence the distributions and abundances of a sub-alpine amphibian assemblage whose members display a variety of different life-history and defence strategies. Our study was conducted in the sub-alpine lentic habitats of three wilderness areas that form the core of the Klamath-Siskiyou Bioregion of northern...

Water demand for ski resort development in the Austrian Alps: an Overview

NASA Astrophysics Data System (ADS)

Breiling, M.; Sokratov, S.

2012-04-01

Austria has the highest national added value from winter tourism in Europe, as well as worldwide. 15.7 million arrivals were counted in Austrian accommodation establishments in the 2010/11 winter season. There were more than 62 million overnight stays and 51.2 million skier-days were consumed. 588 million transports were carried out by more than 3000 lifts (cable cars, chair lifts and T-bars). Including indirect and induced effects, this resulted in more than 10 billion euros in added value being generated. The lack of snow in many Austrian skiing areas during the 2006/2007 winter season demonstrated the extent to which meteorological conditions influence operations. Declines in the number of skiers transported and total skier days were the result. The cable-car operators also had to struggle with little snow in the 2010/2011 winter. The Austrian Cable Car Operators' Association stated that the opening of 70-80% of all skiing areas outside of the peak season could only be assured through the use of snowmaking equipment. The central criterion for winter sports enthusiasts to make a trip is the guarantee that they will find snow at their destination and Austria's cable-car operators invest more than 100 million euros in the erection and improvement of snowmaking complexes every year to satisfy this deand. In the 2010/2011 season, this provided for 17,800 jobs. Cable car operators set up snowmaking equipment to become independent from meteorological conditions and improve the capacity utilisation of their expensive investments in transport systems in the early winter. Austria has a skiing area of around 25,400 hectares - around 17,000 hectares at altitudes between 600m and 3200m are currently suitable for snowmaking. As much as 70% of the snow is produced immediately before the start of the season. This recent trend is responsible that the irrigation pattern of Austrian land use changed significantly in the last decade. Previously maize fields and low lands in summer were the most important irrigated land, now high altitude mountain areas and winter are the largest irrigated areas. We assume the production of 6000 cubic metres of artificial snow per hectare per season. This results in around 100 million cubic metres of artificial snow to cover a slope area of 17,000 hectares that would be produced using 57 million cubic metres of water (incluing losses). In winter, Austrian skiing areas use almost as much water as the capital city of Vienna during the same period. The water demand could again be reduced up to 30% by snow making with help of the dendrite generator, a recent innovation that has not entered the market yet. Water savings also affect the energy requirements where savings of up to 40% are predicted and leads to improved resoure use, greater ecological compatibility and an increase in profitability.

Involvement of the c-Ski oncoprotein in cell cycle arrest and transformation during nurse cell formation after Trichinella spiralis infection.

PubMed

Wu, Z; Nagano, I; Boonmars, T; Takahashi, Y

2006-09-01

The role of c-Ski, an oncoprotein encoded by the oncogene, c-ski, in Trichinella spiralis-infected muscle tissues during nurse cell formation, was investigated by following the expression kinetics and distribution of c-Ski (both protein and mRNA) in the infected muscle cell, as well as the expression kinetics of the transforming growth factor beta (TGF-beta) signaling pathway factor genes (TGF-beta, Smad2 and Smad4) which cooperate with c-Ski. Immunohistochemical analysis using an anti-c-Ski antibody indicated that in the early stages of infection (13 and 18 days post-infection (p.i.)) the increased expression of the c-Ski protein was limited to the eosinophilic cytoplasm and not the enlarged nuclei or basophilic cytoplasm. At a later stage of infection (23 and 28 days p.i.) the c-Ski protein was limited to the enlarged nuclei in the basophilic cytoplasm, rather than the eosinophilic cytoplasm. At 48 days p.i., the c-Ski protein was barely detectable. Real-time PCR analysis showed that expression of the c-ski gene increased from 13 days p.i., reached a peak at 23-28 days p.i. and then decreased to a low level by 48 days p.i. Expression kinetics for the TGF-beta signaling pathway factor genes (TGF-beta, Smad2 and Smad4) were similar to that of c-ski. These findings provide evidence that the c-Ski protein is involved in nurse cell formation through the TGF-beta signaling pathway process in the host cell nucleus.

SKI promotes Smad3 linker phosphorylations associated with the tumor-promoting trait of TGFbeta.

PubMed

Lin, Qiushi; Chen, Dahu; Timchenko, Nikolai A; Medrano, Estela E

2010-05-01

The transcriptional co-regulator SKI is a potent inhibitor of TGFbeta-growth inhibitory signals. SKI binds to receptor-activated Smads in the nucleus, forming repressor complexes containing HDACs, mSin3, NCoR, and other protein partners. Alternatively, SKI binds to activated Smads in the cytoplasm, preventing their nuclear translocation. SKI is necessary for anchorage-independent growth of melanoma cells in vitro, and most important, for human melanoma xenograft growth in vivo. We recently identified a novel role of SKI in TGFbeta signaling. SKI promotes the switch of Smad3 from repressor of proliferation to activator of oncogenesis by facilitating phosphorylations in the linker domain. High levels of endogenous SKI are required by the tumor promoting trait of TGFbeta to induce expression of the plasminogen-activator inhibitor-1 (PAI-1), sustained expression of C-Myc and for aborting upregulation of p21(Waf-1). Here we discuss how SKI diversifies and amplifies its functions by associating with multiple protein partners and by promoting Smad3 linker phosphorylation(s) in response to TGFbeta signaling in melanoma cells.

Tank Investigation of the Grumman JRF-5 Airplane Equipped with Twin Hydro-Skis TED No. NACA DE 357

NASA Technical Reports Server (NTRS)

Ramsen, John A.; Gray, George R.

1951-01-01

A tank investigation has been conducted on a 1/8-size powered dynamic model of the Grumman JRF-5 airplane equipped with twin hydro-skis. The results of tests using two types of skis are presented: one had vertical sides joining the top surface to the chine; the other had the top surface faired to the chine to eliminate the vertical sides. Both configurations had satisfactory longitudinal stability although the model had a slightly greater stable elevator range available when the skis without the vertical sides were attached. Free model tests indicated no instability present when one ski emerged before the other. Considerable excess thrust was available at all speeds with either type of skis. A hump gross load-resistance ratio of 3.37 was obtained with the skis with the vertical sides and 3.53 with the other skis. Landing behavior in smooth water with yaw up to 15deg and roll up to 15deg in opposite directions was satisfactory with either type of skis.

Monitoring coal mine changes and their impact on landscape patterns in an alpine region: a case study of the Muli coal mine in the Qinghai-Tibet Plateau.

PubMed

Qian, Dawen; Yan, Changzhen; Xing, Zanpin; Xiu, Lina

2017-10-14

The Muli coal mine is the largest open-cast coal mine in the Qinghai-Tibet Plateau, and it consists of two independent mining sites named Juhugeng and Jiangcang. It has received much attention due to the ecological problems caused by rapid expansion in recent years. The objective of this paper was to monitor the mining area and its surrounding land cover over the period 1976-2016 utilizing Landsat images, and the network structure of land cover changes was determined to visualize the relationships and pattern of the mining-induced land cover changes. In addition, the responses of the surrounding landscape pattern were analysed by constructing gradient transects. The results show that the mining area was increasing in size, especially after 2000 (increased by 71.68 km 2 ), and this caused shrinkage of the surrounding lands, including alpine meadow wetland (53.44 km 2 ), alpine meadow (6.28 km 2 ) and water (6.24 km 2 ). The network structure of the mining area revealed the changes in lands surrounding the mining area. The impact of mining development on landscape patterns was mainly distributed within a range of 1-6 km. Alpine meadow wetland was most affected in Juhugeng, while alpine meadow was most affected in Jiangcang. The results of this study provide a reference for the ecological assessment and restoration of the Muli coal mine land.

Carbon sequestration in two alpine soils on the Tibetan Plateau.

PubMed

Tian, Yu-Qiang; Xu, Xing-Liang; Song, Ming-Hua; Zhou, Cai-Ping; Gao, Qiong; Ouyang, Hua

2009-09-01

Soil carbon sequestration was estimated in a conifer forest and an alpine meadow on the Tibetan Plateau using a carbon-14 radioactive label provided by thermonuclear weapon tests (known as bomb-(14)C). Soil organic matter was physically separated into light and heavy fractions. The concentration spike of bomb-(14)C occurred at a soil depth of 4 cm in both the forest soil and the alpine meadow soil. Based on the depth of the bomb-(14)C spike, the carbon sequestration rate was determined to be 38.5 g C/m(2) per year for the forest soil and 27.1 g C/m(2) per year for the alpine meadow soil. Considering that more than 60% of soil organic carbon (SOC) is stored in the heavy fraction and the large area of alpine forests and meadows on the Tibetan Plateau, these alpine ecosystems might partially contribute to "the missing carbon sink".

A comparison between energy transfer and atmospheric turbulent exchanges over alpine meadow and banana plantation

NASA Astrophysics Data System (ADS)

Ding, Zhangwei; Ma, Yaoming; Wen, Zhiping; Ma, Weiqiang; Chen, Shiji

2017-07-01

Banana plantation and alpine meadow ecosystems in southern China and the Tibetan Plateau (TP) are unique in the underlying surfaces they exhibit. In this study, we used eddy covariance and a micrometeorological tower to examine the characteristics of land surface energy exchanges over a banana plantation in southern China and an alpine meadow in the Tibetan Plateau from May 2010 to August 2012. The results showed that the diurnal and seasonal variations in upward shortwave radiation flux and surface soil heat flux were larger over the alpine meadow than over the banana plantation surface. Dominant energy partitioning varied with season. Latent heat flux was the main consumer of net radiation flux in the growing season, whereas sensible heat flux was the main consumer during other periods. The Monin-Obukhov similarity theory was employed for comparative purposes, using sonic anemometer observations of flow over the surfaces of banana plantations in the humid southern China monsoon region and the semi-arid areas of the TP, and was found to be applicable. Over banana plantation and alpine meadow areas, the average surface albedo and surface aerodynamic roughness lengths under neutral atmospheric conditions were ˜0.128 and 0.47 m, and ˜0.223 and 0.01 m, respectively. During the measuring period, the mean annual bulk transfer coefficients for momentum and sensible heat were 1.47 × 10-2 and 7.13 × 10-3, and 2.91 × 10-3 and 1.96 × 10-3, for banana plantation and alpine meadow areas, respectively.

The Evolution of Champion Cross-Country-Skier Training: From Lumberjacks to Professional Athletes.

PubMed

Sandbakk, Øyvind

2017-02-01

Competitive cross-country (XC) skiing has traditions extending back to the mid-19th century and was included as a men's event in the first Winter Games in 1924. Since then, tremendous improvements in equipment, track preparation, and knowledge about training have prompted greater increases in XC-skiing speeds than in any other Olympic sport. In response, this commentary focuses on how the training of successful XC skiers has evolved, with interviews and training data from surviving Norwegian world and Olympic XC champions as primary sources. Before 1970, most male champion XC skiers were lumberjacks who ran or skied long distances to and from felling areas while working long days in the woods. In addition, they trained as much as possible, with increased intensity during the autumn, while less work but more ski-specific training and competitions were done during the winter. Until the 1970s, few XC skiers were women, whom coaches believed tolerated less training than men did. Today's XC skiers are less physically active, but the influence of both science and the systematic approaches of former athletes and coaches have gradually taught XC skiers to adopt smarter, more goal-oriented training practices. Although the very high VO 2 max of world-class XC skiers has remained the same since the 1960s, new events in modern XC skiing have additionally required superior upper-body power, high-speed techniques, and tactical flexibility. These elements also emerge in the training of today's best skiers; women's physiological capacities and training routines especially seem to have improved dramatically.

Snow Based Winter Tourism and Kinds of Adaptations to Climate Change

NASA Astrophysics Data System (ADS)

Breiling, M.

2009-04-01

Austria is the most intensive winter tourism country in the world with some 4% contribution in the national GNP. Snow based winter tourism became the lead economy of mountain areas, covering two thirds of the country and is by far economically more important than agriculture and forestry. While natural snow was the precondition for the establishment of winter tourism, artificial snow is nowadays the precondition to maintain winter tourism in the current economic intensity. Skiing originally low tech, is developing increasingly into high tech. While skiing was comparatively cheap in previous days due to natural snow, skiing is getting more expensive and exclusive for a higher income class due to the relative high production costs. Measures to adapt to a warmer climate can be divided into three principle types: physical adaptation, technical adaptation - where artificial snow production plays a major role - and social adaptation. It will be discussed under which conditions each adaptation type seems feasible in dependence of the level of warming. In particular physical and technical adaptations are related to major investments. Practically every ski resort has to decide about what is an appropriate, economically cost efficient level of adaptation. Adapting too much reduces profits. Adapting too little does not bring enough income. The optimal level is often not clear. In many cases public subsidies help to collect funds for adaptation and to keep skiing profitable. The possibility to adapt on local, regional or on national scales will depend on the degree of warming, the future price of artificial snow production and the public means foreseen to support the winter tourism industry.

Ski co-repressor complexes maintain the basal repressed state of the TGF-beta target gene, SMAD7, via HDAC3 and PRMT5.

PubMed

Tabata, Takanori; Kokura, Kenji; Ten Dijke, Peter; Ishii, Shunsuke

2009-01-01

The products encoded by ski and its related gene, sno, (Ski and Sno) act as transcriptional co-repressors and interact with other co-repressors such as N-CoR/SMRT and mSin3A. Ski and Sno mediate transcriptional repression by various repressors, including Mad, Rb and Gli3. Ski/Sno also suppress transcription induced by multiple activators, such as Smads and c-Myb. In particular, the inhibition of TGF-beta-induced transcription by binding to Smads is correlated with the oncogenic activity of Ski and Sno. However, the molecular mechanism by which Ski and Sno mediate transcriptional repression remains unknown. In this study, we report the purification and characterization of Ski complexes. The Ski complexes purified from HeLa cells contained histone deacetylase 3 (HDAC3) and protein arginine methyltransferase 5 (PRMT5), in addition to multiple Smad proteins (Smad2, Smad3 and Smad4). Chromatin immunoprecipitation assays indicated that these components of the Ski complexes were localized on the SMAD7 gene promoter, which is the TGF-beta target gene, in TGF-beta-untreated HepG2 cells. Knockdown of these components using siRNA led to up-regulation of SMAD7 mRNA. These results indicate that Ski complexes serve to maintain a TGF-beta-responsive promoter at a repressed basal level via the activities of histone deacetylase and histone arginine methyltransferase.

Measuring Snow Precipitation in New Zealand- Challenges and Opportunities.

NASA Astrophysics Data System (ADS)

Renwick, J. A.; Zammit, C.

2015-12-01

Monitoring plays a pivotal role in determining sustainable strategy for efficient overall management of the water resource. Though periodic monitoring provides some information, only long-term monitoring can provide data sufficient in quantity and quality to determine trends and develop predictive models. These can support informed decisions about sustainable and efficient use of water resources in New Zealand. However the development of such strategies is underpinned by our understanding and our ability to measure all inputs in headwaters catchments, where most of the precipitation is falling. Historically due to the harsh environment New Zealand has had little to no formal high elevation monitoring stations for all climate and snow related parameters outside of ski field climate and snow stations. This leads to sparse and incomplete archived datasets. Due to the importance of these catchments to the New Zealand economy (eg irrigation, hydro-electricity generation, tourism) NIWA has developed a climate-snow and ice monitoring network (SIN) since 2006. This network extends existing monitoring by electricity generator and ski stations and it is used by a number of stakeholders. In 2014 the network comprises 13 stations located at elevation above 700masl. As part of the WMO Solid Precipitation Intercomparison Experiment (SPICE), NIWA is carrying out an intercomparison of precipitation data over the period 2013-2015 at Mueller Hut. The site was commissioned on 11 July 2013, set up on the 17th September 2013 and comprises two Geonor weighing bucket raingauges, one shielded and the other un-shielded, in association with a conventional tipping bucket raingauge and conventional climate and snow measurements (temperature, wind, solar radiation, relative humidity, snow depth and snow pillow). The presentation aims to outline the state of the current monitoring network in New Zealand, as well as the challenge and opportunities for measurement of precipitation in alpine environment.

Sports Injury and Illness Epidemiology: Great Britain Olympic Team (TeamGB) surveillance during the Sochi 2014 Winter Olympic Games

PubMed Central

Palmer-Green, Debbie; Elliott, Niall

2015-01-01

Background Sports injury and illness surveillance is the first step in injury and illness prevention, and is important for the protection of both athlete health and performance in major competitions. Aim To identify the prevalence, severity nature and causes of athlete injuries and illnesses in the Great Britain Olympic Team (TeamGB) during the Sochi 2014 Winter Olympic Games. Methods The observational prospective cohort study followed the Great Britain Injury/Illness Performance Project surveillance methodology and obtained information on injuries and illnesses that occurred during the Games between 30 January and 23 February 2014 in TeamGB athletes (n=56). Results Among the 56 TeamGB athletes, there were 27 injuries and 11 illnesses during the Olympic Games period. This equated to 39% sustaining at least one injury and 18% at least one illness, with an incidence of 48.2 injuries and 19.6 illnesses per 100 athletes, respectively. Of all injuries and illnesses, 9% and 7%, respectively, resulted in time loss. The risk of sustaining an injury was highest for freestyle skiing, skeleton and snowboarding; and lowest for curling, biathlon and Alpine skiing (with no reported injuries); with the lower limb being the most commonly injured location. Respiratory system illnesses were most frequently reported overall, and older female athletes were the ones most affected by illness. Conclusions The risk of injury was double the risk of illness for TeamGB athletes. Overall, the rate of time-loss issues was low. Methodological considerations are important when interpreting data, and prevention strategies should focus on those issues causing the greatest risk, in terms of prevalence and severity, to athlete health and performance. PMID:25425714

Soil warming increases plant species richness but decreases germination from the alpine soil seed bank.

PubMed

Hoyle, Gemma L; Venn, Susanna E; Steadman, Kathryn J; Good, Roger B; McAuliffe, Edward J; Williams, Emlyn R; Nicotra, Adrienne B

2013-05-01

Global warming is occurring more rapidly above the treeline than at lower elevations and alpine areas are predicted to experience above average warming in the future. Temperature is a primary factor in stimulating seed germination and regulating changes in seed dormancy status. Thus, plant regeneration from seed will be crucial to the persistence, migration and post disturbance recruitment of alpine plants in future climates. Here, we present the first assessment of the impact of soil warming on germination from the persistent alpine soil seed bank. Contrary to expectations, soil warming lead to reduced overall germination from the soil seed bank. However, germination response to soil temperature was species specific such that total species richness actually increased by nine with soil warming. We further explored the system by assessing the prevalence of seed dormancy and germination response to soil disturbance, the frequency of which is predicted to increase under climate change. Seeds of a significant proportion of species demonstrated physiological dormancy mechanisms and germination of several species appeared to be intrinsically linked to soil disturbance. In addition, we found no evidence of subalpine species and little evidence of exotic weed species in the soil, suggesting that the soil seed bank will not facilitate their invasion of the alpine zone. In conclusion, changes in recruitment via the alpine soil seed bank can be expected under climate change, as a result of altered dormancy alleviation and germination cues. Furthermore, the alpine soil seed bank, and the species richness therein, has the potential to help maintain local species diversity, support species range shift and moderate species dominance. Implications for alpine management and areas for further study are also discussed. © 2013 Blackwell Publishing Ltd.

Do Maximal Roller Skiing Speed and Double Poling Performance Predict Youth Cross-Country Skiing Performance?

PubMed Central

Stöggl, Roland; Müller, Erich; Stöggl, Thomas

2017-01-01

The aims of the current study were to analyze whether specific roller skiing tests and cycle length are determinants of youth cross-country (XC) skiing performance, and to evaluate sex specific differences by applying non-invasive diagnostics. Forty-nine young XC skiers (33 boys; 13.8 ± 0.6 yrs and 16 girls; 13.4 ± 0.9 yrs) performed roller skiing tests consisting of both shorter (50 m) and longer durations (575 m). Test results were correlated with on snow XC skiing performance (PXC) based on 3 skating and 3 classical distance competitions (3 to 6 km). The main findings of the current study were: 1) Anthropometrics and maturity status were related to boys’, but not to girls’ PXC; 2) Significant moderate to acceptable correlations between girls’ and boys’ short duration maximal roller skiing speed (double poling, V2 skating, leg skating) and PXC were found; 3) Boys’ PXC was best predicted by double poling test performance on flat and uphill, while girls’ performance was mainly predicted by uphill double poling test performance; 4) When controlling for maturity offset, boys’ PXC was still highly associated with the roller skiing tests. The use of simple non-invasive roller skiing tests for determination of PXC represents practicable support for ski clubs, schools or skiing federations in the guidance and evaluation of young talent. Key points Double poling tests on flat and uphill terrain and short duration maximal speed tests were the highest cross-country skiing predicting factors in girls and boys. Only in the boys there was an effect of maturation on the performance outcomes, pointing out that girls seem to be almost fully matured at the age of 13 in contrast to the boys. Roller skiing tests over short distance (50-m) and longer distance 225 m and 350 m are stable and valid measures and suitable for performance prediction in youth cross-country skiers. PMID:28912656

Overexpression of SKI Oncoprotein Leads to p53 Degradation through Regulation of MDM2 Protein Sumoylation*

PubMed Central

Ding, Boxiao; Sun, Yin; Huang, Jiaoti

2012-01-01

Protooncogene Ski was identified based on its ability to transform avian fibroblasts in vitro. In support of its oncogenic activity, SKI was found to be overexpressed in a variety of human cancers, although the exact molecular mechanism(s) responsible for its oncogenic activity is not fully understood. We found that SKI can negatively regulate p53 by decreasing its level through up-regulation of MDM2 activity, which is mediated by the ability of SKI to enhance sumoylation of MDM2. This stimulation of MDM2 sumoylation is accomplished through a direct interaction of SKI with SUMO-conjugating enzyme E2, Ubc9, resulting in enhanced thioester bond formation and mono-sumoylation of Ubc9. A mutant SKI defective in transformation fails to increase p53 ubiquitination and is unable to increase MDM2 levels and to increase mono-sumoylation of Ubc9, suggesting that the ability of SKI to enhance Ubc9 activity is essential for its transforming function. These results established a detailed molecular mechanism that underlies the ability of SKI to cause cellular transformation while unraveling a novel connection between sumoylation and tumorigenesis, providing potential new therapeutic targets for cancer. PMID:22411991

The Phosphatidylinositol 3-Kinase/Akt Pathway Regulates Transforming Growth Factor-β Signaling by Destabilizing Ski and Inducing Smad7*

PubMed Central

Band, Arja M.; Björklund, Mia; Laiho, Marikki

2009-01-01

Ski is an oncoprotein that negatively regulates transforming growth factor (TGF)-β signaling. It acts as a transcriptional co-repressor by binding to TGF-β signaling molecules, Smads. Efficient TGF-β signaling is facilitated by rapid proteasome-mediated degradation of Ski by TGF-β. Here we report that Ski is phosphorylated by Akt/PKB kinase. Akt phosphorylates Ski on a highly conserved Akt motif at threonine 458 both in vitro and in vivo. The phosphorylation of Ski at threonine 458 is induced by Akt pathway activators including insulin, insulin-like growth factor-1, and hepatocyte growth factor. The phosphorylation of Ski causes its destabilization and reduces Ski-mediated inhibition of expression of another negative regulator of TGF-β, Smad7. Induction of Smad7 levels leads to inactivation of TGF-β receptors and TGF-β signaling cascade, as indicated by reduced induction of TGF-β target p15. Therefore, Akt modulates TGF-β signaling by temporarily adjusting the levels of two TGF-β pathway negative regulators, Ski and Smad7. These novel findings demonstrate that Akt pathway activation directly impacts TGF-β pathway. PMID:19875456

Response of alpine vegetation growth dynamics to snow cover phenology on the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Wang, X.; Wu, C.

2017-12-01

Alpine vegetation plays a crucial role in global energy cycles with snow cover, an essential component of alpine land cover showing high sensitivity to climate change. The Tibetan Plateau (TP) has a typical alpine vegetation ecosystem and is rich of snow resources. With global warming, the snow of the TP has undergone significant changes that will inevitably affect the growth of alpine vegetation, but observed evidence of such interaction is limited. In particular, a comprehensive understanding of the responses of alpine vegetation growth to snow cover variability is still not well characterized on TP region. To investigate this, we calculated three indicators, the start (SOS) and length (LOS) of growing season, and the maximum of normalized difference vegetation index (NDVImax) as proxies of vegetation growth dynamics from the Moderate Resolution Imaging Spectroradiometer (MODIS) data for 2000-2015. Snow cover duration (SCD) and melt (SCM) dates were also extracted during the same time frame from the combination of MODIS and the Interactive Multi-sensor Snow and Ice Mapping System (IMS) data. We found that the snow cover phenology had a strong control on alpine vegetation growth dynamics. Furthermore, the responses of SOS, LOS and NDVImax to snow cover phenology varied among plant functional types, eco-geographical zones, and temperature and precipitation gradients. The alpine steppes showed a much stronger negative correlation between SOS and SCD, and also a more evidently positive relationship between LOS and SCD than other types, indicating a longer SCD would lead to an earlier SOS and longer LOS. Most areas showed positive correlation between SOS and SCM, while a contrary response was also found in the warm but drier areas. Both SCD and SCM showed positive correlations with NDVImax, but the relationship became weaker with the increase of precipitation. Our findings provided strong evidences between vegetation growth and snow cover phenology, and changes in snow cover should be also considered when analyzing alpine vegetation growth dynamics in future.

Motor abilities and anthropometrics in youth cross-country skiing.

PubMed

Stöggl, R; Müller, E; Stöggl, T

2015-02-01

The purposes were to validate whether general motor abilities and anthropometrics are determinants of youth cross-country (XC) skiing performance; evaluate gender-specific differences; and to establish noninvasive diagnostics. Fifty-one youth XC skiers (34 boys; 13.8 ± 0.6 years and 17 girls; 13.4 ± 0.9 years) performed motor skill and laboratory tests, and anthropometric data were collected and correlated with XC skiing performance. Anthropometrics and maturity status were related to boys but not to girls XC skiing performance. Push-ups and 20-m sprint were correlated to XC skiing performance in both boys and girls. XC skiing performance of boys was predominantly influenced by upper body and trunk strength capacities (medicine ball throw, push-ups, and pull-ups) and jumping power (standing long and triple jump), whereas XC skiing of girls was mainly influenced by aerobic capacities (3000-m run). Laboratory measures did not reveal greater correlations to XC skiing performance compared with simple test concepts of speed, strength, and endurance. Maturity was a major confounding variable in boys but not girls. Use of noninvasive simple test concepts for determination of upper body strength, speed, and endurance represent practicable support for ski clubs, schools, or skiing federations in the guidance and evaluation of young talent, being aware of the effect of maturity especially in boys. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

c-Ski overexpression promotes tumor growth and angiogenesis through inhibition of transforming growth factor-beta signaling in diffuse-type gastric carcinoma.

PubMed

Kiyono, Kunihiko; Suzuki, Hiroshi I; Morishita, Yasuyuki; Komuro, Akiyoshi; Iwata, Caname; Yashiro, Masakazu; Hirakawa, Kosei; Kano, Mitsunobu R; Miyazono, Kohei

2009-10-01

c-Ski, originally identified as a proto-oncogene product, is an important negative regulator of transforming growth factor (TGF)-beta family signaling through interaction with Smad2, Smad3, and Smad4. High expression of c-Ski has been found in some cancers, including gastric cancer. We previously showed that disruption of TGF-beta signaling by dominant-negative TGF-beta type II receptor in a diffuse-type gastric carcinoma model accelerated tumor growth through induction of tumor angiogenesis by decreased expression of the anti-angiogenic factor thrombospondin (TSP)-1. Here, we examined the function of c-Ski in human diffuse-type gastric carcinoma OCUM-2MLN cells. Overexpression of c-Ski inhibited TGF-beta signaling in OCUM-2MLN cells. Interestingly, c-Ski overexpression resulted in extensive acceleration of the growth of subcutaneous xenografts in BALB/c nu/nu female mice (6 weeks of age). Similar to tumors expressing dominant-negative TGF-beta type II receptor, histochemical studies revealed less fibrosis and increased angiogenesis in xenografted tumors expressing c-Ski compared to control tumors. Induction of TSP-1 mRNA by TGF-beta was attenuated by c-Ski in vitro, and expression of TSP-1 mRNA was decreased in tumors expressing c-Ski in vivo. These findings suggest that c-Ski overexpression promotes the growth of diffuse-type gastric carcinoma through induction of angiogenesis.

Assessment of heavy metal pollution risks and enzyme activity of meadow soils in urban area under tourism load: a case study from Zakopane (Poland).

PubMed

Ciarkowska, Krystyna

2018-05-01

Effect of tourism, especially skiing activities, and urbanization on chemical and biochemical properties of soils in touristy town-Zakopane-was investigated. The concentration of heavy metals, nutrients, soil organic matter (SOM), dehydrogenase (DHA), invertase (IA) and urease (Ure) activities in soils from the town centre and out of the town centre was compared with the respective values of adjacent soils in protected areas (TNP). In order to evaluate a degree of contamination and risks of degradation enrichment factor (EF), ecological risk index (RI), Nemerov Pollution Index (PI Nemerov ) as well as enzyme activity index (EAI) were calculated. Soils in the centre of Zakopane were polluted with Zn, Pb, Cd and Cu in a moderate degree when those of skiing areas were polluted with Pb and Cd in a high degree. Strong positive correlation between these metals and negative correlation between them and a distance from the main roundabout in town indicated their anthropogenic origin. Soils of both locations were also enriched in P, but depleted in SOM when compared to TNP soils. Soils of touristy areas (out of the centre) were additionally enriched in N. Activity of studied enzymes was also lowered in soils of Zakopane when compared to soils of TNP. Pollution indices, RI, PI Nemerov as well as EAI, indicated that soils of Zakopane are at risk of degradation. Soils of touristy areas are under stronger negative impact than soils of the centre because of the cumulative effect of transport of heavy metals from the city centre, pollution by skiing machinery and melting water from the artificial snow.

Ski and SnoN, potent negative regulators of TGF-β signaling

PubMed Central

Deheuninck, Julien; Luo, Kunxin

2011-01-01

Ski and the closely related SnoN were discovered as oncogenes by their ability to transform chicken embryo fibroblasts upon overexpression. While elevated expressions of Ski and SnoN have also been reported in many human cancer cells and tissues, consistent with their pro-oncogenic activity, emerging evidence also suggests a potential anti-oncogenic activity for both. In addition, Ski and SnoN have been implicated in regulation of cell differentiation, especially in the muscle and neuronal lineages. Multiple cellular partners of Ski and SnoN have been identified in an effort to understand the molecular mechanisms underlying the complex roles of Ski and SnoN. In this review, we summarize recent findings on the biological functions of Ski and SnoN, their mechanisms of action and how their levels of expression are regulated. PMID:19114989

Changes in vegetation cover and composition in the Swedish mountain region.

PubMed

Hedenås, Henrik; Christensen, Pernilla; Svensson, Johan

2016-08-01

Climate change, higher levels of natural resource demands, and changing land use will likely lead to changes in vegetation configuration in the mountain regions. The aim of this study was to determine if the vegetation cover and composition have changed in the Swedish region of the Scandinavian Mountain Range, based on data from the long-term landscape biodiversity monitoring program NILS (National Inventory of Landscapes in Sweden). Habitat type and vegetation cover were assessed in 1740 systematically distributed permanent field plots grouped into 145 sample units across the mountain range. Horvitz-Thompson estimations were used to estimate the present areal extension of the alpine and the mountain birch forest areas of the mountain range, the cover of trees, shrubs, and plants, and the composition of the bottom layer vegetation. We employed the data from two subsequent 5-year monitoring periods, 2003-2007 and 2008-2012, to determine if there have been any changes in these characteristics. We found that the extension of the alpine and the mountain birch forest areas has not changed between the inventory phases. However, the total tree canopy cover increased in the alpine area, the cover of graminoids and dwarf shrubs and the total cover of field vegetation increased in both the alpine area and the mountain birch forest, the bryophytes decreased in the alpine area, and the foliose lichens decreased in the mountain birch forest. The observed changes in vegetation cover and composition, as assessed by systematic data in a national and regional monitoring scheme, can validate the results of local studies, experimental studies, and models. Through benchmark assessments, monitoring data also contributes to governmental policies and land-management strategies as well as to directed cause and effect analyses.

Regional climate models downscaling in the Alpine area with Multimodel SuperEnsemble

NASA Astrophysics Data System (ADS)

Cane, D.; Barbarino, S.; Renier, L. A.; Ronchi, C.

2012-08-01

The climatic scenarios show a strong signal of warming in the Alpine area already for the mid XXI century. The climate simulations, however, even when obtained with Regional Climate Models (RCMs), are affected by strong errors where compared with observations, due to their difficulties in representing the complex orography of the Alps and limitations in their physical parametrization. Therefore the aim of this work is reducing these model biases using a specific post processing statistic technique to obtain a more suitable projection of climate change scenarios in the Alpine area. For our purposes we use a selection of RCMs runs from the ENSEMBLES project, carefully chosen in order to maximise the variety of leading Global Climate Models and of the RCMs themselves, calculated on the SRES scenario A1B. The reference observation for the Greater Alpine Area are extracted from the European dataset E-OBS produced by the project ENSEMBLES with an available resolution of 25 km. For the study area of Piedmont daily temperature and precipitation observations (1957-present) were carefully gridded on a 14-km grid over Piedmont Region with an Optimal Interpolation technique. Hence, we applied the Multimodel SuperEnsemble technique to temperature fields, reducing the high biases of RCMs temperature field compared to observations in the control period. We propose also the first application to RCMS of a brand new probabilistic Multimodel SuperEnsemble Dressing technique to estimate precipitation fields, already applied successfully to weather forecast models, with careful description of precipitation Probability Density Functions conditioned to the model outputs. This technique reduces the strong precipitation overestimation by RCMs over the alpine chain and reproduces well the monthly behaviour of precipitation in the control period.

The prevalence and predictors of helmet use by skiers and snowboarders at ski areas in western North America in 2001.

PubMed

Buller, David B; Andersen, Peter A; Walkosz, Barbara J; Scott, Michael D; Cutter, Gary R; Dignan, Mark B; Voeks, Jenifer H

2003-11-01

Helmets may protect the heads of skiers and snowboarders. The prevalence of helmet use by these groups was estimated. Helmet use was observed in face-to-face surveys (N = 2,978) on sun protection at 28 ski areas in Alaska, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Utah, and British Columbia (0.7% refusal rate) from January to April 2001. Helmets were worn by 12.1% (95% confidence interval [CI], 11.0-13.3) of the sample. Use was highest among guests who skied or snowboarded more frequently (fourth quartile vs. first quartile, odds ratio [OR] = 11.998 [95% CI, 6.774-21.251]; third vs. first, OR = 5.556 [95% CI, 3.119-9.896]; second vs. first, OR = 2.186 [95% CI, 1.162-4.112]), were experts (OR = 3.326 [95% CI, 1.297-8.528]), used snowboards (OR = 2.301 [95% CI, 1.731-3.058]), and were more educated (college graduate, OR = 2.167 [95% CI, 1.271-3.695]; some college, OR = 1.969 [95% CI, 1.130-3.431]). Helmet use was generally low but may be high enough by experts, snowboarders, and in the central Rocky Mountains to produce a norm stimulating further adoption.

50 CFR 27.33 - Water skiing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...

50 CFR 27.33 - Water skiing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...

50 CFR 27.33 - Water skiing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...

50 CFR 27.33 - Water skiing.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...

50 CFR 27.33 - Water skiing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...

Lake surface area variation and its responses to climatic change in Yamzhog Yumco Basin, South Tibet during 1970-2010

NASA Astrophysics Data System (ADS)

Zhang, X.; Tian, Y.; Sun, R.

2015-12-01

The research on lake extraction from multi-source and multi-temporal satellite images and the lake size variation can provide reliable method and indispensable information to deepen the understanding about alpine lake changes with the accelerating warming. With field survey experience in the Yamzhog Yumco Basin, South Tibet, the outlines of five lakes (i.e., Yamzhog Yumco, Chen Co, Kongmu Co, Bajiu Co and Puma Yumco) were delineated by the adoption of 42 scenes of satellite images from Landsat, CBERS and HJ from 1970 to 2010, basing on which the responses of alpine lakes to climate change at different timescales were explored. The results are summarized as follows. (1) The seasonal fluctuation of lake surface area was similar with different trend for the five alpine lakes. As for the last 41 years, the annual variation of lake surface area exhibited two kinds of patterns for the five alpine lakes. And the Yamzhog Yumco declined by 9.41%, while the rest four lakes expanded. (2) The responses of alpine lakes to climate change rely on different timescale and water replenishment types. On the one hand, the precipitation change was the predominant driving forces for the seasonal fluctuation and variation trend of lake size, and the rising temperature accounted for the inter-annual lake surface variation. On the other hand, the two kinds of alpine lakes behaviors were well correspondent with the warming temperature over the Qinghai-Tibetan Plateau. The lakes supplied mainly by precipitation shrunk as a result of increased evaporation, and lakes supplied mainly by glacier and snow meltwater, however, expanded because of the remarkable glacier recession. (3) The quantification of hydrological components would hopefully be improved, according to uncertainties analysis, with the adoption of microwave satellite images and higher resolution ones to disclose the interaction mechanism among climate, glacier, and lake in alpine regions.

Ski jump takeoff performance predictions for a mixed-flow, remote-lift STOVL aircraft

NASA Technical Reports Server (NTRS)

Birckelbaw, Lourdes G.

1992-01-01

A ski jump model was developed to predict ski jump takeoff performance for a short takeoff and vertical landing (STOVL) aircraft. The objective was to verify the model with results from a piloted simulation of a mixed flow, remote lift STOVL aircraft. The prediction model is discussed. The predicted results are compared with the piloted simulation results. The ski jump model can be utilized for basic research of other thrust vectoring STOVL aircraft performing a ski jump takeoff.

Ski Area Recreational Opportunity Enhancement Act of 2010

THOMAS, 111th Congress

Sen. Udall, Mark [D-CO

2009-03-17

Senate - 09/27/2010 Placed on Senate Legislative Calendar under General Orders. Calendar No. 590. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Organic matter controls of soil water retention in an alpine grassland and its significance for hydrological processes

NASA Astrophysics Data System (ADS)

Yang, Fei; Zhang, Gan-Lin; Yang, Jin-Ling; Li, De-Cheng; Zhao, Yu-Guo; Liu, Feng; Yang, Ren-Min; Yang, Fan

2014-11-01

Soil water retention influences many soil properties and soil hydrological processes. The alpine meadows and steppes of the Qilian Mountains on the northeast border of the Qinghai-Tibetan Plateau form the source area of the Heihe River, the second largest inland river in China. The soils of this area therefore have a large effect on water movement and storage of the entire watershed. In order to understand the controlling factors of soil water retention and how they affect regional eco-hydrological processes in an alpine grassland, thirty-five pedogenic horizons in fourteen soil profiles along two facing hillslopes in typical watersheds of this area were selected for study. Results show that the extensively-accumulated soil organic matter plays a dominant role in controlling soil water retention in this alpine environment. We distinguished two mechanisms of this control. First, at high matric potentials soil organic matter affected soil water retention mainly through altering soil structural parameters and thereby soil bulk density. Second, at low matric potentials the water adsorbing capacity of soil organic matter directly affected water retention. To investigate the hydrological functions of soils at larger scales, soil water retention was compared by three generalized pedogenic horizons. Among these soil horizons, the mattic A horizon, a diagnostic surface horizon of Chinese Soil Taxonomy defined specially for alpine meadow soils, had the greatest soil water retention over the entire range of measured matric potentials. Hillslopes with soils having these horizons are expected to have low surface runoff. This study promotes the understanding of the critical role of alpine soils, especially the vegetated surface soils in controlling the eco-hydrological processes in source regions of the Heihe River watershed.

Cross-Country Skiing Today.

ERIC Educational Resources Information Center

Caldwell, John

This book presents changes in cross country skiing which have taken place in the last several years and is directed toward both beginning and seasoned tour skiers. Discussed are the following topics: (1) the cross-country revolution (new fiberglass skis); (2) equipment (how to choose from the new waxless touring skis); (3) care of equipment; (4)…

Interaction with Smad4 is indispensable for suppression of BMP signaling by c-Ski.

PubMed

Takeda, Masafumi; Mizuide, Masafumi; Oka, Masako; Watabe, Tetsuro; Inoue, Hirofumi; Suzuki, Hiroyuki; Fujita, Toshiro; Imamura, Takeshi; Miyazono, Kohei; Miyazawa, Keiji

2004-03-01

c-Ski is a transcriptional corepressor that interacts strongly with Smad2, Smad3, and Smad4 but only weakly with Smad1 and Smad5. Through binding to Smad proteins, c-Ski suppresses signaling of transforming growth factor-beta (TGF-beta) as well as bone morphogenetic proteins (BMPs). In the present study, we found that a mutant of c-Ski, termed c-Ski (ARPG) inhibited TGF-beta/activin signaling but not BMP signaling. Selectivity was confirmed in luciferase reporter assays and by determination of cellular responses in mammalian cells (BMP-induced osteoblastic differentiation of C2C12 cells and TGF-beta-induced epithelial-to-mesenchymal transdifferentiation of NMuMG cells) and Xenopus embryos. The ARPG mutant recruited histone deacetylases 1 (HDAC1) to the Smad3-Smad4 complex but not to the Smad1/5-Smad4 complex. c-Ski (ARPG) was unable to interact with Smad4, and the selective loss of suppression of BMP signaling by c-Ski (ARPG) was attributed to the lack of Smad4 binding. We also found that c-Ski interacted with Smad3 or Smad4 without disrupting Smad3-Smad4 heteromer formation. c-Ski (ARPG) would be useful for selectively suppressing TGF-beta/activin signaling.

Interaction with Smad4 Is Indispensable for Suppression of BMP Signaling by c-Ski

PubMed Central

Takeda, Masafumi; Mizuide, Masafumi; Oka, Masako; Watabe, Tetsuro; Inoue, Hirofumi; Suzuki, Hiroyuki; Fujita, Toshiro; Imamura, Takeshi; Miyazono, Kohei; Miyazawa, Keiji

2004-01-01

c-Ski is a transcriptional corepressor that interacts strongly with Smad2, Smad3, and Smad4 but only weakly with Smad1 and Smad5. Through binding to Smad proteins, c-Ski suppresses signaling of transforming growth factor-β (TGF-β) as well as bone morphogenetic proteins (BMPs). In the present study, we found that a mutant of c-Ski, termed c-Ski (ARPG) inhibited TGF-β/activin signaling but not BMP signaling. Selectivity was confirmed in luciferase reporter assays and by determination of cellular responses in mammalian cells (BMP-induced osteoblastic differentiation of C2C12 cells and TGF-β–induced epithelial-to-mesenchymal transdifferentiation of NMuMG cells) and Xenopus embryos. The ARPG mutant recruited histone deacetylases 1 (HDAC1) to the Smad3-Smad4 complex but not to the Smad1/5-Smad4 complex. c-Ski (ARPG) was unable to interact with Smad4, and the selective loss of suppression of BMP signaling by c-Ski (ARPG) was attributed to the lack of Smad4 binding. We also found that c-Ski interacted with Smad3 or Smad4 without disrupting Smad3-Smad4 heteromer formation. c-Ski (ARPG) would be useful for selectively suppressing TGF-β/activin signaling. PMID:14699069

Ski regulates Hippo and TAZ signaling to suppress breast cancer progression

PubMed Central

Rashidian, Juliet; Le Scolan, Erwan; Ji, Xiaodan; Zhu, Qingwei; Mulvihill, Melinda M.; Nomura, Daniel; Luo, Kunxin

2015-01-01

Ski, the transforming protein of the avian Sloan-Kettering retrovirus, inhibits transforming growth factor–β (TGF-β)/Smad signaling and displays both pro-oncogenic and anti-oncogenic activities in human cancer. Inhibition of TGF-β signaling is likely responsible for the pro-oncogenic activity of Ski. We investigated the mechanism(s) underlying the tumor suppressor activity of Ski and found that Ski suppressed the activity of the Hippo signaling effectors TAZ and YAP to inhibit breast cancer progression. TAZ and YAP are transcriptional coactivators that can contribute to cancer by promoting proliferation, tumorigenesis, and cancer stem cell expansion. Hippo signaling activates the the Lats family of kinases, which phosphorylate TAZ and YAP, resulting in cytoplasmic retention and degradation and inhibition of their transcriptional activity. We showed that Ski interacted with multiple components of the Hippo pathway to facilitate activation of Lats2, resulting in increased phosphorylation and subsequent degradation of TAZ. Ski also promoted the degradation of a constitutively active TAZ mutant that is not phosphorylated by Lats, suggesting the existence of a Lats2-independent degradation pathway. Finally, we showed that Ski repressed the transcriptional activity of TAZ by binding to the TAZ partner TEAD and recruiting the transcriptional co-repressor NCoR1 to the TEAD-TAZ complex. Ski effectively reversed transformation and epithelial-to-mesenchyme transition in cultured breast cancer cells and metastasis in TAZ-expressing xenografted tumors. Thus, Ski inhibited the function of TAZ through multiple mechanisms in human cancer cells. PMID:25670202

The transforming activity of Ski and SnoN is dependent on their ability to repress the activity of Smad proteins.

PubMed

He, Jun; Tegen, Sarah B; Krawitz, Ariel R; Martin, G Steven; Luo, Kunxin

2003-08-15

The regulation of cell growth and differentiation by transforming growth factor-beta (TGF-beta) is mediated by the Smad proteins. In the nucleus, the Smad proteins are negatively regulated by two closely related nuclear proto-oncoproteins, Ski and SnoN. When overexpressed, Ski and SnoN induce oncogenic transformation of chicken embryo fibroblasts. However, the mechanism of transformation by Ski and SnoN has not been defined. We have previously reported that Ski and SnoN interact directly with Smad2, Smad3, and Smad4 and repress their ability to activate TGF-beta target genes through multiple mechanisms. Because Smad proteins are tumor suppressors, we hypothesized that the ability of Ski and SnoN to inactivate Smad function may be responsible for their transforming activity. Here, we show that the receptor regulated Smad proteins (Smad2 and Smad3) and common mediator Smad (Smad4) bind to different regions in Ski and SnoN. Mutation of both regions, but not each region alone, markedly impaired the ability of Ski and SnoN to repress TGF-beta-induced transcriptional activation and cell cycle arrest. Moreover, when expressed in chicken embryo fibroblasts, mutant Ski or SnoN defective in binding to the Smad proteins failed to induce oncogenic transformation. These results suggest that the ability of Ski and SnoN to repress the growth inhibitory function of the Smad proteins is required for their transforming activity. This may account for the resistance to TGF-beta-induced growth arrest in some human cancer cell lines that express high levels of Ski or SnoN.

Differential role of Sloan–Kettering Institute (Ski) protein in Nodal and transforming growth factor-beta (TGF-β)-induced Smad signaling in prostate cancer cells

PubMed Central

Khan, Shafiq A.

2012-01-01

Transforming growth factor-beta (TGF-β) signaling pathways contain both tumor suppressor and tumor promoting activities. We have demonstrated that Nodal, another member of the TGF-β superfamily, and its receptors are expressed in prostate cancer cells. Nodal and TGF-β exerted similar biological effects on prostate cells; both inhibited proliferation in WPE, RWPE1 and DU145 cells, whereas neither had any effect on the proliferation of LNCaP or PC3 cells. Interestingly, Nodal and TGF-β induced migration in PC3 cells, but not in DU145 cells. TGF-β induced predominantly phosphorylation of Smad3, whereas Nodal induced phosphorylation of only Smad2. We also determined the expression and differential role of Ski, a corepressor of Smad2/3, in Nodal and TGF-β signaling in prostate cancer cells. Similar levels of Ski mRNA were found in several established prostate cell lines; however, high levels of Ski protein were only detected in prostate cancer cells and prostate cancer tissue samples. Exogenous Nodal and TGF-β had no effects on Ski mRNA levels. On the other hand, TGF-β induced a rapid degradation of Ski protein mediated by the proteasomal pathway, whereas Nodal had no effect on Ski protein. Reduced Ski levels correlated with increased basal and TGF-β-induced Smad2/3 phosphorylation. Knockdown of endogenous Ski reduced proliferation in DU145 cells and enhanced migration of PC3 cells. We conclude that high levels of Ski expression in prostate cancer cells may be responsible for repression of TGF-β and Smad3 signaling, but Ski protein levels do not influence Nodal and Smad2 signaling. PMID:22843506

Ski Inhibits TGF-β/phospho-Smad3 Signaling and Accelerates Hypertrophic Differentiation in Chondrocytes

PubMed Central

Kim, Kyung-Ok; Sampson, Erik R.; Maynard, Robert D; O'Keefe, Regis J.; Chen, Di; Drissi, Hicham; Rosier, Randy N.; Hilton, Matthew J.; Zuscik, Michael J.

2012-01-01

Since TGF-β/Smad signaling inhibits chondrocyte maturation, endogenous negative regulators of TGF-β signaling are likely also important regulators of the chondrocyte differentiation process. One such negative regulator, Ski, is an oncoprotein that is known to inhibit TGF-β/Smad3 signaling via its interaction with phospho-Smad3 and recruitment of histone deacetylases (HDACs) to the DNA binding complex. Based on this, we hypothesized that Ski inhibits TGF-β signaling and accelerates maturation in chondrocytes via recruitment of HDACs to transcriptional complexes containing Smads. We tested this hypothesis in chick upper sternal chondrocytes (USCs), where gain and loss of Ski expression experiments were performed. Over-expression of Ski not only reversed the inhibitory effect of TGF-β on the expression of hypertrophic marker genes such as type × collagen (colX) and osteocalcin, it induced these genes basally as well. Conversely, knockdown of Ski by RNA interference led to a reduction of colX and osteocalcin expression under basal conditions. Furthermore, Ski blocked TGF-β induction of cyclinD1 and caused a basal up-regulation of Runx2, consistent with the observed acceleration of hypertrophy. Regarding mechanism, not only does Ski associate with phospho-Smad2 and 3, but its association with phospho-Smad3 is required for recruitment of HDAC4 and 5. Implicating this recruitment of HDACs in the phenotypic effects of Ski in chondrocytes, the HDAC inhibitor SAHA reversed the up-regulation of colX and osteocalcin in Ski over-expressing cells. These results suggest that inhibition of TGF-β signaling by Ski, which involves its association with phospho-Smad3 and recruitment of HDAC4 and 5, leads to accelerated chondrocyte differentiation. PMID:22461172

Competition between Ski and CREB-binding protein for binding to Smad proteins in transforming growth factor-beta signaling.

PubMed

Chen, Weijun; Lam, Suvana S; Srinath, Hema; Schiffer, Celia A; Royer, William E; Lin, Kai

2007-04-13

The family of Smad proteins mediates transforming growth factor-beta (TGF-beta) signaling in cell growth and differentiation. Smads repress or activate TGF-beta signaling by interacting with corepressors (e.g. Ski) or coactivators (e.g. CREB-binding protein (CBP)), respectively. Specifically, Ski has been shown to interfere with the interaction between Smad3 and CBP. However, it is unclear whether Ski competes with CBP for binding to Smads and whether they can interact with Smad3 at the same binding surface on Smad3. We investigated the interactions among purified constructs of Smad, Ski, and CBP in vitro by size-exclusion chromatography, isothermal titration calorimetry, and mutational studies. Here, we show that Ski-(16-192) interacted directly with a homotrimer of receptor-regulated Smad protein (R-Smad), e.g. Smad2 or Smad3, to form a hexamer; Ski-(16-192) interacted with an R-Smad.Smad4 heterotrimer to form a pentamer. CBP-(1941-1992) was also found to interact directly with an R-Smad homotrimer to form a hexamer and with an R-Smad.Smad4 heterotrimer to form a pentamer. Moreover, these domains of Ski and CBP competed with each other for binding to Smad3. Our mutational studies revealed that domains of Ski and CBP interacted with Smad3 at a portion of the binding surface of the Smad anchor for receptor activation. Our results suggest that Ski negatively regulates TGF-beta signaling by replacing CBP in R-Smad complexes. Our working model suggests that Smad protein activity is delicately balanced by Ski and CBP in the TGF-beta pathway.

Snow management practices in French ski resorts

NASA Astrophysics Data System (ADS)

Spandre, Pierre; Francois, Hugues; George-Marcelpoil, Emmanuelle; Morin, Samuel

2016-04-01

Winter tourism plays a fundamental role in the economy of French mountain regions but also in other countries such as Austria, USA or Canada. Ski operators originally developed grooming methods to provide comfortable and safe skiing conditions. The interannual variability of snow conditions and the competition with international destinations and alternative tourism activities encouraged ski resorts to mitigate their dependency to weather conditions through snowmaking facilities. However some regions may not be able to produce machine made snow due to inadequate conditions and low altitude resorts are still negatively impacted by low snow seasons. In the meantime, even though the operations of high altitude resorts do not show any dependency to the snow conditions they invest in snowmaking facilities. Such developments of snowmaking facilities may be related to a confused and contradictory perception of climate change resulting in individualistic evolutions of snowmaking facilities, also depending on ski resorts main features such as their altitude and size. Concurrently with the expansion of snowmaking facilities, a large range of indicators have been used to discuss the vulnerability of ski resorts such as the so-called "100 days rule" which was widely used with specific thresholds (i.e. minimum snow depth, dates) and constraints (i.e. snowmaking capacity). The present study aims to provide a detailed description of snow management practices and major priorities in French ski resorts with respect to their characteristics. We set up a survey in autumn 2014, collecting data from 56 French ski operators. We identify the priorities of ski operators and describe their snowmaking and grooming practices and facilities. The operators also provided their perception of the ski resort vulnerability to snow and economic challenges which we could compare with the actual snow conditions and ski lift tickets sales during the period from 2001 to 2012.

Increasing Sun Protection in Winter Outdoor Recreation

PubMed Central

Walkosz, Barbara J.; Buller, David B.; Andersen, Peter A.; Scott, Michael D.; Dignan, Mark B.; Cutter, Gary R.; Maloy, Julie A.

2009-01-01

Background Unprotected and excessive exposure to ultraviolet radiation (UVR) is the primary risk factor for skin cancer. Design A pair-matched, group-randomized, pre-test/post-test, quasi-experimental design, with ski resorts as the unit of randomization, tested the effectiveness of Go Sun Smart, a multi-channel skin cancer prevention program. Independent samples of guests were taken at baseline (2001) and follow-up (2002); data were analyzed in 2006. Setting and Participants A total of 6516 adult guests at 26 ski resorts in the western U.S. and Canada were recruited, consented, and interviewed on chairlifts. This study was nested within an occupational intervention for ski resort workers. Intervention Ski resorts were pair-matched and randomized to receive Go Sun Smart, which consisted of print, electronic, visual, and interpersonal skin cancer prevention messages. Main Outcome Measures Sun-protection behaviors, sunburning, recall of sun-protection messages, and the association of message exposure to sun protection. Results The difference in recall of all sun-protection messages, messages on signs and posters, and the Go Sun Smart logo was significant between the intervention and control resorts. Reported use of sun-protection practices was higher by guests at intervention ski areas using more (a higher dose of) Go Sun Smart materials. Intervention-group guests who recalled a sun-safety message were more likely to practice sun safety than intervention-group guests who did not recall a message and control-group guests. Conclusions While the mere implementation of Go Sun Smart did not produce sun-safety improvements, Go Sun Smart appeared to be effective for guests who encountered and remembered it. Many factors can work against message exposure. Signage seemed to produce the greatest increase in exposure to sun-safety messages. PMID:18471586

Is proglacial field an important contributor to runoff in glacierized watershed? Lesson learned from a case study in Duke River watershed, Yukon, Canada.

NASA Astrophysics Data System (ADS)

Chesnokova, A.; Baraer, M.

2017-12-01

Sub-Arctic glacierized catchments are complex hydrological systems of paramount importance not only for water resources management but also for various ecosystem services. Those areas are environmentally fragile and host many climate-sensitive components of hydrological cycle. In a context of shifting from glacial to non-glacial regimes in Sub-Arctic, this study focuses on understanding hydrological role of proglacial field in runoff generation in headwaters of Duke River watershed, Canada, by comparing to that of alpine meadow (area that is not recently reworked by glacier). Duke Glacier, as many glaciers in St. Elias Mountains, is a surging glacier, and produced debris-charged dead-ice masses once the last surge has seized. In addition, such features as ice-cored moraines and taluses are found in proglacial field. Those features are hypothesised to cause high storage capacity and complex groundwater distribution systems which might affect significantly watershed hydrology. In order to estimate the contribution of different components of the alpine meadow and the proglacial field to runoff, HBCM, a multi-component distributed hydrochemical mixing model (Baraer et al., 2015) was applied. During field campaign in June 2016, 157 samples were taken from possible hydrological sources (end-members) and from main stream, and analysed for major ions, dissolved organic compounds and heavy stable water isotopes. End-members contribution was quantified based on tracer concentration at mixing points. Discharge was measured 6 km downstream from the glacier snout so that both proglacial field and alpine meadow occupy comparable areas of the catchment. Results show the difference between main water sources for the two hydrological systems: buried ice, ice-cored moraines and groundwater sources within proglacial field, and groundwater and supra-permafrost water within alpine meadow. Overall contribution of glaciers during June 2016 exceeded the contribution of the rest of the components of hydrological system. However, water production from both proglacial field and alpine meadow was significant, with proglacial field yielding more water than alpine meadow. Since the Duke Glacier keeps retreating, the area of proglacial field is increasing as well as it role in runoff generation in the area.

Industry sources of trend data - skiing

Treesearch

William F., Jr. Malcolm

1980-01-01

With precious few exceptions, ski industry trend data does not exist. This paper will enumerate sources of trend data known to the author. The paper considers the probable causes of the lack of ski industry trend data and means to ameliorate the lack of trend data. Finally, the paper presents a rationale for acquiring improved ski industry trend data.

Ski Area Recreational Opportunity Enhancement Act of 2010

THOMAS, 111th Congress

Rep. DeGette, Diana [D-CO-1

2009-05-19

Senate - 09/30/2010 Read twice. Placed on Senate Legislative Calendar under General Orders. Calendar No. 636. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

Snowmaking in ski resorts: spatial decision support for management of snowpack

NASA Astrophysics Data System (ADS)

Loubier, Jean-Christophe; Kanevski, Mikhail; Doctor, Marut; Schumacher, Michael; Timonin, Vadim

2010-05-01

Since the early 2000s, the question of snowmaking that ensures activity in ski areas is controversial, because solutions to face climate change and sustainable development seem to be opposed to the economical needs of winter tourism. Actually, according to the Advisory Body on Climate Change (OCCC), we can expect an average rise of the limit of 0 degrees to 360 m in 2050. The application of the rule of 100 days (30 cm of snow for 100 days) shows that 1 ° increase in temperature reduced by 20% the number of viable skiing areas. Snowmaking seems thus to be a solution for continuing an optimal economical usage of the ski resorts. The usage of machine-made snow raises environmental issues which can no longer be denied. [Badre et al.2009] However, these issues should not be disconnected from local economic specificities of the high mountain valleys, where the ski economy is critical. This paper presents a study at the economic-environmental interface. The aim is to develop a tool for managing the production of artificial snow, with the goal to: • Reduce production costs and improve profit margins of companies operating ski areas; • Reduce environmental impacts by an optimized snow production "just in time". In this way, water and energy needs will be reduced. The problem of managing the snow is a highly complex problem: it cannot be solved analytically. Indeed, changes in height of snow are subject to intakes of snow (natural or manufactured) associated with changing weather conditions and the impact of skiers. Therefore, the work presented in this paper has chosen a probabilistic approach in a simulation using neural networks to predict and to manage snow height. We do this in two points: • We measure snowpack heights with radars mounted on grooming machines; • We produce a snow cover prediction in relation with weather prediction using a neuron network. This neural approach thus deals with the spatial prediction of snow cover [Kanevski et al., 2009] The result is a map of probable heights provided to stakeholders, allowing them to adjust their production strategy based on the situation. Acknowledgements This work was partly supported by Swiss CTI project "Juste Neige". Bibliography SHARDUL Agrawala (ed)2007;Climate Change in the European Alps Adapting Winter Tourism and Natural Hazards Management; OECD Publishing Paris, France BADRE Michel, PRIME Jean-Louis, RIBIERE Georges 2009 ; Neige de culture : état des lieux et impacts environnementaux - Note socio-économique ; Conseil général de l'environnement et du développement durable ; Paris ; France DE JONG, Carmen., 2008. 'Resource conflicts in mountain: source and solutions'. Mountain Forum Bulletin 8:1,pp. 5-7. KANEVSKI Mikhail, POZDNOUKHOV Alexei, and TIMONIN Vadim (2009); Machine Learning for Spatial Environmental Data. Theory, Applications" Softwsare. EPFL and CRC Press.

Red deer as maintenance host for bovine tuberculosis, Alpine region.

PubMed

Fink, Maria; Schleicher, Corina; Gonano, Monika; Prodinger, Wolfgang M; Pacciarini, Maria; Glawischnig, Walter; Ryser-Degiorgis, Marie-Pierre; Walzer, Chris; Stalder, Gabrielle L; Lombardo, Dorotea; Schobesberger, Hermann; Winter, Petra; Büttner, Mathias

2015-03-01

To estimate the prevalence of bovine tuberculosis in the Alpine region, we studied the epidemiology of Mycobacterium caprae in wildlife during the 2009-2012 hunting seasons. Free-ranging red deer (Cervus elaphus) were a maintenance host in a hot-spot area, mainly located in Austria.

Ecological Impacts of Revegetation and Management Practices of Ski Slopes in Northern Finland

NASA Astrophysics Data System (ADS)

Kangas, Katja; Tolvanen, Anne; Kälkäjä, Tarja; Siikamäki, Pirkko

2009-09-01

Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003-2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.

Ecological impacts of revegetation and management practices of ski slopes in northern Finland.

PubMed

Kangas, Katja; Tolvanen, Anne; Kälkäjä, Tarja; Siikamäki, Pirkko

2009-09-01

Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003-2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.

Research and Development in the Anthropogenic Cryosphere

NASA Astrophysics Data System (ADS)

de Jong, C.; Luthe, T.; Hohenwallne, D.

2009-04-01

Much of todays cryosphere research is oriented towards the polar regions and is strongly supported by large associations and funding. On the other hand, funding and institutional support is still limited for mountains. In Europe, mountain research is mainly funded through Alpine Space Interregs, FP7, ESF and COST. However, there is growing global change pressure on mountain regions, particularly in the more fragile, higher altitudes such as between 1000 - 3200 m in the Alps. Although these zones are comparable to the Arctic in terms of climatic and physiographic conditions, they are not in terms of human pressures and atmospheric pollution released from surrounding agglomerations. A re-orientation of research into more applied projects that tackle present day problems is necessary. Not only is climate change rapidly changing the face of mountains, socio-economic multipliers are also acting fast. New problems such as conflicts over natural resources are evolving at a rapid rate, requiring research funding and projects to respond at according rates if timely and efficient solutions are to be proposed. Other problems include contamination of high altitude lakes and ecosystems through atmospheric precipitation of persistent organic pollutants and concentration of radio-active substances. The rapid melt of glacier ice is also releasing pollutants that have been captured for many decades. Many of the present day problems develop due to a miscomprehension of the cryosphere. Short-term economical reasoning outweighs the long-term ecological impacts that could be very counter-productive at the long term. Both the glaciological, snow, permafrost, geomorphological, ecological, hydrological and atmospheric conditions are increasingly heavily modified by human impacts. The effects include the alteration of the ice cover (by artificial covering of glaciers), production of artificial snow cover, snow and ground compaction, erosion, landsliding, change in vegetation cover and fauna, modification of local hydrological cycle and modification of local climate and atmospheric pollution. Research in mountains should balance the needs of scientists and stakeholders alike, but this requires re-orientation of mountain research into multi-disciplinary projects next to basic science. Unlike the polar regions (with exceptions like Longyearbyen, Spitzbergen), seasonal population pressure in mountains is intense, causing local problems such as water scarcity. Research in these areas therefore requires close collaboration with stakeholders. Large-scale events such as Winter Olympics that have benefited from the classical mountain cryosphere in the past are now increasingly becoming internationally competitive and independent of the natural cryospheric conditions. New ski areas are developed world-wide in zones that do not offer natural climatological conditions for maintaining ski runs. Sub-zero temperatures are used as a basis for snow-making even in those regions that do not benefit from sufficient natural snow-fall. Large-scale landscape modification results in motorway like ski runs, large snow water reservoirs and extensive housing projects on vulnerable slopes. Due to steep and remote topography, transport is often dominated by cars and increases CO2 emissions intensively at local hot spots. In future, mountain slopes that have been heavily modified for winter tourism, may rapidly become neglected zones due to rapid snowline retreat. As the summer season extends, the modifications to the cryosphere will become more and more evident. Even with positive temperatures and snow-free ground, the vegetation season will not be extensive enough to enable rapid recovery, especially at altitudes above 2000 m a.s.l and north-facing aspects. Several decades of anthropogenic modification may require several centuries of recovery to provide new economical benefits.

Improving alpine-region spectral unmixing with optimal-fit snow endmembers

NASA Technical Reports Server (NTRS)

Painter, Thomas H.; Roberts, Dar A.; Green, Robert O.; Dozier, Jeff

1995-01-01

Surface albedo and snow-covered-area (SCA) are crucial inputs to the hydrologic and climatologic modeling of alpine and seasonally snow-covered areas. Because the spectral albedo and thermal regime of pure snow depend on grain size, areal distribution of snow grain size is required. Remote sensing has been shown to be an effective (and necessary) means of deriving maps of grain size distribution and snow-covered-area. Developed here is a technique whereby maps of grain size distribution improve estimates of SCA from spectral mixture analysis with AVIRIS data.

The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease.

PubMed

Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M; Liddicoat, Brian; Russell, Megan R; Walkley, Carl R; Karlsson, Stefan

2014-04-01

The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease.

Localization and roles of Ski8p protein in Sordaria meiosis and delineation of three mechanistically distinct steps of meiotic homolog juxtaposition.

PubMed

Tessé, Sophie; Storlazzi, Aurora; Kleckner, Nancy; Gargano, Silvana; Zickler, Denise

2003-10-28

Ski8p is implicated in degradation of non-poly(A) and double-stranded RNA, and in meiotic DNA recombination. We have identified the Sordaria macrospora SKI8 gene. Ski8p is cytoplasmically localized in all vegetative and sexual cycle cells, and is nuclear localized, specifically in early-mid-meiotic prophase, in temporal correlation with Spo11p, the meiotic double-strand break (DSB) transesterase. Localizations of Ski8p and Spo11p are mutually interdependent. ski8 mutants exhibit defects in vegetative growth, entry into the sexual program, and sporulation. Diverse meiotic defects, also seen in spo11 mutants, are diagnostic of DSB absence, and they are restored by exogenous DSBs. These results suggest that Ski8p promotes meiotic DSB formation by acting directly within meiotic prophase chromosomes. Mutant phenotypes also divide meiotic homolog juxtaposition into three successive, mechanistically distinct steps; recognition, presynaptic alignment, and synapsis, which are distinguished by their differential dependence on DSBs.

Localization and roles of Ski8p protein in Sordaria meiosis and delineation of three mechanistically distinct steps of meiotic homolog juxtaposition

PubMed Central

Tessé, Sophie; Storlazzi, Aurora; Kleckner, Nancy; Gargano, Silvana; Zickler, Denise

2003-01-01

Ski8p is implicated in degradation of non-poly(A) and double-stranded RNA, and in meiotic DNA recombination. We have identified the Sordaria macrospora SKI8 gene. Ski8p is cytoplasmically localized in all vegetative and sexual cycle cells, and is nuclear localized, specifically in early-mid-meiotic prophase, in temporal correlation with Spo11p, the meiotic double-strand break (DSB) transesterase. Localizations of Ski8p and Spo11p are mutually interdependent. ski8 mutants exhibit defects in vegetative growth, entry into the sexual program, and sporulation. Diverse meiotic defects, also seen in spo11 mutants, are diagnostic of DSB absence, and they are restored by exogenous DSBs. These results suggest that Ski8p promotes meiotic DSB formation by acting directly within meiotic prophase chromosomes. Mutant phenotypes also divide meiotic homolog juxtaposition into three successive, mechanistically distinct steps; recognition, presynaptic alignment, and synapsis, which are distinguished by their differential dependence on DSBs. PMID:14563920

The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease

PubMed Central

Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M.; Liddicoat, Brian; Russell, Megan R.; Walkley, Carl R.; Karlsson, Stefan

2014-01-01

The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease. PMID:24415629

The genus Hebeloma in the alpine belt of the Carpathians including two new species.

PubMed

Eberhardt, Ursula; Ronikier, Anna; Schütz, Nicole; Beker, Henry J

2015-01-01

Between 2002 and 2012 regular visits to the Carpathians were made and a number of Hebeloma spp. were collected from the alpine area. In total 44 collections were made that represent 11 species, two of which, Hebeloma grandisporum and H. oreophilum, are described here as new. Of the 11 species, four (H. alpinum, H. marginatulum and the two species described as new) are known only from alpine or Arctic habitats. Hebeloma dunense and H. mesophaeum are commonly found in, but not restricted to, alpine habitats. The other five species (H. aanenii, H. laterinum, H. naviculosporum, H. vaccinum, H. velutipes) are usually found in lowland or boreal habitats. Hebeloma naviculosporum is reported for the first time from the alpine zone and H. alpinum for the first time as growing with Helianthemum. All but two species (H. alpinum, H. marginatulum) are reported for the first time from the Carpathian alpine zone. In this paper we discuss the habitat, the 11 recorded species and give detailed descriptions of the two new species, both morphologically and molecularly. A key for Hebeloma species from sect. Hebeloma occurring in Arctic-alpine habitats is provided. © 2015 by The Mycological Society of America.

Adverse impacts of pasture abandonment in Himalayan protected areas: Testing the efficiency of a Natural Resource Management Plan (NRMP)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nautiyal, Sunil; Kaechele, Harald

2007-03-15

The high elevational areas in the Himalayas of India are dominated by forests and alpine pastures. There are many protected areas in the region, including Nanda Devi Biosphere Reserve (NDBR) and Valley of Flowers (VOF) where natural resource management plan (NRMP) has been implemented for the conservation of biodiversity. This has affected the traditional animal husbandry system, as well as the vegetation dynamics of alpine pastures. An integrated approach to studying the impact of NRMP in the region has been applied by us. First, a survey was conducted regarding livestock management, data pertaining the livestock husbandry, the role of animalmore » husbandry in economics of rural household, and socioeconomics. Second, field based study on phytosociology of some important alpine herbs was done to enumerate the density and species richness in different land mark of the region. Thereafter, satellite data and Geographic Information System (GIS) were used to develop a land cover map of the area and to note changes in the landscape over time after implementation of NRMP. From an economic point of view the implementation of such plan is a setback to the rural economy. However, the ecological perspective of such models is a threat to the diversity of alpine pastures. The invasion of bushes/thorny bushes/shrubs and weeds with their luxuriant growth is changing the vegetation index and dynamics. Consequently, the diversity of herbs in alpine pastures of the Himalayan Mountains is in jeopardy. Overall, the situation is leading to landscape change in the region. This study is helpful for generating useful outcomes and strategies considering the question or debate 'is grazing good or bad for pasture ecosystems in the Himalayas?'.« less

SEA in local land use planning - first experience in the Alpine States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiricka, Alexandra; Proebstl, Ulrike

2008-05-15

In the Alpine area, planning decisions can result in far-reaching consequences because of the high sensitivity of the Alpine ecosystems. This article is based on two hypotheses: (1) The Alpine states/regions were aware of their sensitive environment and therefore recognized the necessity of introducing a comparable instrument to assess local land use planning. (2) By introducing this differentiated assessment tool, namely SEA, an increase in costs may be the consequence. However, better and more transparent planning can contribute to the enhancement of planning standards. To reveal the validity of these assumptions the legal implementation in the Alpine countries Austria, Germany,more » Italy and France was examined as well as first practical experience resulting from the determined procedures. The results of the implementation process in the four states were compared and discussed on the basis of selected process steps of SEA.« less

Mesozoic and Cenozoic structural evolution of North Oman: New insights from high-quality 3D seismic from the Lekhwair area

NASA Astrophysics Data System (ADS)

Bazalgette, Loïc; Salem, Hisham

2018-06-01

This paper highlights the role of Triassic-Jurassic extension and late Cretaceous compression in the Mesozoic-Cenozoic (Alpine) structuring of North Oman. The syn/post-Mesozoic regional structural evolution is usually documented as a succession of two stages of deformation. The Alpine 1 phase, late Cretaceous in age, occurred in association with two ophiolite obduction stages (Semail and Masirah ophiolites). It was characterised by strike slip to extensional deformation in the North Oman foreland basin sub-surface. The Alpine 2 phase, Miocene in age, was related to the continental collision responsible for both the Zagros orogen and the uplift of the Oman Mountains. The Alpine 2 deformation was transpressional to compressional. Observation and interpretation of good quality 3D seismic in the Lekhwair High area enabled the distinction of two earlier phases. Early Mesozoic extension occurred concomitantly with the regional Triassic to Jurassic rifting, developing Jurassic-age normal faults. Late Cretaceous compression occurred prior to the main Alpine 1 phase and triggered the inversion of Jurassic-seated normal faults as well as the initiation of compressional folds in the Cretaceous overburden. These early phases have been ignored or overlooked as part of the North Oman history although they are at the origin of structures hosting major local and regional hydrocarbon accumulations.

Structurally controlled 'teleconnection' of large-scale mass wasting (Eastern Alps)

NASA Astrophysics Data System (ADS)

Ostermann, Marc; Sanders, Diethard

2015-04-01

In the Brenner Pass area (Eastern Alps) , closely ahead of the most northward outlier ('nose') of the Southern-Alpine continental indenter, abundant deep-seated gravitational slope deformations and a cluster of five post-glacial rockslides are present. The indenter of roughly triangular shape formed during Neogene collision of the Southern-Alpine basement with the Eastern-Alpine nappe stack. Compression by the indenter activated a N-S striking, roughly W-E extensional fault northward of the nose of the indenter (Brenner-normal fault; BNF), and lengthened the Eastern-Alpine edifice along a set of major strike-slip faults. These fault zones display high seismicity, and are the preferred locus of catastrophic rapid slope failures (rockslides, rock avalanches) and deep-seated gravitational slope deformations. The seismotectonic stress field, earthquake activity, and structural data all indicate that the South-Alpine indenter still - or again - exerts compression; in consequence, the northward adjacent Eastern Alps are subject mainly to extension and strike-slip. For the rockslides in the Brenner Pass area, and for the deep-seated gravitational slope deformations, the fault zones combined with high seismic activity predispose massive slope failures. Structural data and earthquakes mainly record ~W-E extension within an Eastern Alpine basement block (Oetztal-Stubai basement complex) in the hangingwall of the BNF. In the Northern Calcareous Alps NW of the Oetztal-Stubai basement complex, dextral faults provide defacement scars for large rockfalls and rockslides. Towards the West, these dextral faults merge into a NNW-SSE striking sinistral fault zone that, in turn, displays high seismic activity and is the locus of another rockslide cluster (Fern Pass cluster; Prager et al., 2008). By its kinematics dictated by the South-Alpine indenter, the relatively rigid Oetztal-Stubai basement block relays faulting and associated mass-wasting over a N-S distance of more than 60 kilometers - from the Brenner Pass area located along the crestline of the Alps to mount Zugspitze near the northern fringe of the Northern Calcareous Alps. Major fault zones and intercalated rigid blocks thus can 'teleconnect' zones of preferred mass-wasting over large lateral distances in orogens. Reference: Prager, C., Zangerl, C., Patzelt, G., Brandner, R., 2008. Age distribution of fossil landslides in the Tyrol (Austria) and its surrounding areas. Natural Hazards and Earth System Science 8, 377-407.

Reconnaissance data on lakes in the Alpine Lakes Wilderness Area, Washington

USGS Publications Warehouse

Dethier, David P.; Heller, Paul L.; Safioles, Sally A.

1979-01-01

Sixty lakes in the Alpine Lakes Wilderness Area have been sampled from rubber rafts or helicopter to obtain information on their physical setting and on present water-quality conditions. The lakes are located near the crest of the Cascade Range in Chelan and King Counties, Washington. Basic data from these lakes will be useful for planners concerned with lake and wilderness management, and of interest to hikers and other recreationists who use the lakes.

Determinants of a simulated cross-country skiing sprint competition using V2 skating technique on roller skis.

PubMed

Mikkola, Jussi; Laaksonen, Marko; Holmberg, Hans-Christer; Vesterinen, Ville; Nummela, Ari

2010-04-01

The present study investigated the performance-predicting factors of a simulated cross-country (XC) skiing sprint competition on roller skis, on a slow surface. Sixteen elite male XC skiers performed a simulated sprint competition (4 x 850 m heat with a 20-minute recovery) using V2 skating technique on an indoor tartan track. Heat velocities, oxygen consumption, and peak lactate were measured during or after the heats. Maximal skiing velocity was measured by performing a 30-m speed test. Explosive and maximal force production in the upper body was determined by bench press (BP). Subjects also performed maximal anaerobic skiing test (MAST) and the 2 x 2-km double poling (DP) test. The maximal velocity of MAST (VMAST) and velocities at 3 (V3), 5 (V5), 7 (V7) mmol.L lactate levels in MAST were determined. In the 2 x 2-km test, DP economy (VO2SUBDP) and maximal 2-km DP velocity (VDP2KM) were determined. The best single performance-predicting factors for the sprint performance were VDP2KM (r = 0.73, p < 0.01), V7 (r = 0.70, p < 0.01), and VO2SUBDP (r = -0.70, p < 0.01). Faster skiers in sprint simulation had a higher absolute VO2 (L.min) (p < 0.05-0.01) during sprint heats, and higher anaerobic skiing power (VMAST, p < 0.05) and better anaerobic skiing economy (V3, V5, V7, p < 0.05-0.001) than slower skiers. Faster skiers were also stronger in BP, with regard to both absolute (p < 0.01) and relative (p < 0.05) values. In addition, anaerobic characteristics seem to be of importance at the beginning of the XC skiing sprint competition, whereas the aerobic characteristics become more important as the XC skiing sprint competition progressed. This study indicates that sprint skiers should emphasize sport-specific upper body training, and training skiing economy at high speeds.

Efficient TGF-β/SMAD signaling in human melanoma cells associated with high c-SKI/SnoN expression

PubMed Central

2011-01-01

Background SKI and SnoN proteins have been shown to inhibit TGF-β signaling, acting both as transcriptional co-repressors in the cell nucleus, and as sequestrators of SMAD proteins in the cytoplasm. TGF-β, on the other hand, induces rapid, proteasome-mediated, degradation of both proteins. How elevated SKI and SnoN protein levels co-exist with active autocrine TGF-β signaling in cancer cells is yet to be understood. Results In this study, we found elevated SKI and SnoN protein levels in a panel of melanoma cell lines, as compared to normal melanocytes. There was no correlation between SKI protein content and the capacity of melanoma cells to invade Matrigel™, to form subcutaneous tumors, or to metastasize to bone after intracardiac inoculation into nude mice. Nor did we find a correlation between SKI expression and histopathological staging of human melanoma. TGF-β induced a rapid and dose-dependent degradation of SKI protein, associated with SMAD3/4 specific transcriptional response and induction of pro-metastatic target genes, partially prevented by pharmacologic blockade of proteasome activity. SKI knockdown in 1205Lu melanoma cells did not alter their invasive capacity or transcriptional responses to TGF-β, and did not allow p21 expression in response to TGF-β or reveal any growth inhibitory activity of TGF-β. Conclusions Despite high expression in melanoma cells, the role of SKI in melanoma remains elusive: SKI does not efficiently interfere with the pro-oncogenic activities of TGF-β, unless stabilized by proteasome blockade. Its highly labile nature makes it an unlikely target for therapeutic intervention. PMID:21211030

Impact of Communication Barriers on Urban Development of Nowogród Bobrzański

NASA Astrophysics Data System (ADS)

Laskowski, Janusz; Juszczyk, Artur

2016-09-01

Network communication links is an indispensable element of development shaping. Any change in the way of using area should be preceded by an analysis of future impact taking into account the transport capacity. The development of buildings without adequate communication links leads to restrictions on object access, consequently it may lead to dangerous mishaps. Avoiding this type of situation is possible by carrying out sustainable development. The paper describes the relationship between the road system and urban layout on the example of Nowogród Bobrzański part of the city. One presented existing changes in the transportation system and its impact on local residents.

SKI knockdown inhibits human melanoma tumor growth in vivo.

PubMed

Chen, Dahu; Lin, Qiushi; Box, Neil; Roop, Dennis; Ishii, Shunsuke; Matsuzaki, Koichi; Fan, Tao; Hornyak, Thomas J; Reed, Jon A; Stavnezer, Ed; Timchenko, Nikolai A; Medrano, Estela E

2009-12-01

The SKI protein represses the TGF-beta tumor suppressor pathway by associating with the Smad transcription factors. SKI is upregulated in human malignant melanoma tumors in a disease-progression manner and its overexpression promotes proliferation and migration of melanoma cells in vitro. The mechanisms by which SKI antagonizes TGF-beta signaling in vivo have not been fully elucidated. Here we show that human melanoma cells in which endogenous SKI expression was knocked down by RNAi produced minimal orthotopic tumor xenograft nodules that displayed low mitotic rate and prominent apoptosis. These minute tumors exhibited critical signatures of active TGF-beta signaling including high levels of nuclear Smad3 and p21(Waf-1), which are not found in the parental melanomas. To understand how SKI promotes tumor growth we used gain- and loss-of-function approaches and found that simultaneously to blocking the TGF-beta-growth inhibitory pathway, SKI promotes the switch of Smad3 from tumor suppression to oncogenesis by favoring phosphorylations of the Smad3 linker region in melanoma cells but not in normal human melanocytes. In this context, SKI is required for preventing TGF-beta-mediated downregulation of the oncogenic protein c-MYC, and for inducing the plasminogen activator inhibitor-1, a mediator of tumor growth and angiogenesis. Together, the results indicate that SKI exploits multiple regulatory levels of the TGF-beta pathway and its deficiency restores TGF-beta tumor suppressor and apoptotic activities in spite of the likely presence of oncogenic mutations in melanoma tumors.

Convinced, ambivalent or annoyed: Tyrolean ski tourism stakeholders and their perceptions of climate change.

PubMed

Trawöger, Lisa

2014-02-01

Its focus on snow-dependent activities makes Alpine winter tourism especially sensitive to climate change. Stakeholder risk perceptions are a key factor in adaptation to climate change because they fundamentally drive or constrain stakeholder action. This paper examines climate change perceptions of winter tourism stakeholders in Tyrol (Austria). Using a qualitative approach, expert interviews were conducted. Four opinion categories reflecting different attitudes toward climate change issues were identified: convinced planners , annoyed deniers , ambivalent optimists , convinced wait-and-seers . Although the findings generally indicate a growing awareness of climate change, this awareness is mainly limited to perceiving the issue as a global phenomenon. Awareness of regional and branch-specific consequences of climate change that lead to a demand for action could not be identified. Current technical strategies, like snowmaking, are not primarily climate-induced. At present, coping with climate change is not a priority for risk management. The findings point out the importance of gaining and transferring knowledge of regional and branch-specific consequences of climate change in order to induce action at the destination level.

Real-time data acquisition of commercial microwave link networks for hydrometeorological applications

NASA Astrophysics Data System (ADS)

Chwala, Christian; Keis, Felix; Kunstmann, Harald

2016-03-01

The usage of data from commercial microwave link (CML) networks for scientific purposes is becoming increasingly popular, in particular for rain rate estimation. However, data acquisition and availability is still a crucial problem and limits research possibilities. To overcome this issue, we have developed an open-source data acquisition system based on the Simple Network Management Protocol (SNMP). It is able to record transmitted and received signal levels of a large number of CMLs simultaneously with a temporal resolution of up to 1 s. We operate this system at Ericsson Germany, acquiring data from 450 CMLs with minutely real-time transfer to our database. Our data acquisition system is not limited to a particular CML hardware model or manufacturer, though. We demonstrate this by running the same system for CMLs of a different manufacturer, operated by an alpine ski resort in Germany. There, the data acquisition is running simultaneously for four CMLs with a temporal resolution of 1 s. We present an overview of our system, describe the details of the necessary SNMP requests and show results from its operational application.

Real time data acquisition of commercial microwave link networks for hydrometeorological applications

NASA Astrophysics Data System (ADS)

Chwala, C.; Keis, F.; Kunstmann, H.

2015-11-01

The usage of data from commercial microwave link (CML) networks for scientific purposes is becoming increasingly popular, in particular for rain rate estimation. However, data acquisition and availability is still a crucial problem and limits research possibilities. To overcome this issue, we have developed an open source data acquisition system based on the Simple Network Management Protocol (SNMP). It is able to record transmitted- and received signal levels of a large number of CMLs simultaneously with a temporal resolution of up to one second. We operate this system at Ericsson Germany, acquiring data from 450 CMLs with minutely real time transfer to our data base. Our data acquisition system is not limited to a particular CML hardware model or manufacturer, though. We demonstrate this by running the same system for CMLs of a different manufacturer, operated by an alpine skiing resort in Germany. There, the data acquisition is running simultaneously for four CMLs with a temporal resolution of one second. We present an overview of our system, describe the details of the necessary SNMP requests and show results from its operational application.

Convinced, ambivalent or annoyed: Tyrolean ski tourism stakeholders and their perceptions of climate change☆

PubMed Central

Trawöger, Lisa

2014-01-01

Its focus on snow-dependent activities makes Alpine winter tourism especially sensitive to climate change. Stakeholder risk perceptions are a key factor in adaptation to climate change because they fundamentally drive or constrain stakeholder action. This paper examines climate change perceptions of winter tourism stakeholders in Tyrol (Austria). Using a qualitative approach, expert interviews were conducted. Four opinion categories reflecting different attitudes toward climate change issues were identified: convinced planners, annoyed deniers, ambivalent optimists, convinced wait-and-seers. Although the findings generally indicate a growing awareness of climate change, this awareness is mainly limited to perceiving the issue as a global phenomenon. Awareness of regional and branch-specific consequences of climate change that lead to a demand for action could not be identified. Current technical strategies, like snowmaking, are not primarily climate-induced. At present, coping with climate change is not a priority for risk management. The findings point out the importance of gaining and transferring knowledge of regional and branch-specific consequences of climate change in order to induce action at the destination level. PMID:27064520

Repression of endogenous Smad7 by Ski.

PubMed

Denissova, Natalia G; Liu, Fang

2004-07-02

The Ski protein has been proposed to serve as a corepressor for Smad4 to maintain a transforming growth factor-beta (TGF-beta)-responsive promoter at a repressed, basal level. However, there have been no reports so far that it indeed acts on a natural promoter. We have previously cloned the human Smad7 promoter and shown that it contains the 8-base pair palindromic Smad-binding element (SBE) necessary for TGF-beta induction. In this report, we have characterized the negative regulation of Smad7 promoter basal activity by Ski. We show that Ski inhibits the Smad7 promoter basal activity in a SBE-dependent manner. Mutation of the SBE abrogates the inhibitory effect of Ski on the Smad7 promoter. Moreover, mutation of the SBE increases the Smad7 promoter basal activity. Using the chromatin immunoprecipitation assay, we further show that Ski together with Smad4 binds to the endogenous Smad7 promoter. Finally, we show that RNAi knockdown of Ski increases Smad7 reporter gene activity in transient transfection assays as well as elevating the endogenous level of Smad7 mRNA. Taken together, our results provide the first evidence that Ski is indeed a corepressor for Smad4, which can inhibit a natural TGF-beta responsive gene at the basal state.

75 FR 6025 - Environmental Impact Statements and Regulations; Availability of EPA Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-05

..., Vail Ski Area's 2007 Improvement Project, Proposed On-Mountain Restaurant from the top of Vail Mountain... Restaurant from the top of Vail Mountain to Mid Vail, Special-Use-Permit, Eagle/Holy Cross Ranger District...

[Skiing accidents in children (author's transl)].

PubMed

Schwarzenbach, M; Röthlisberger, M; Herwig, K; Biener, K

1981-03-13

In Arosa, a coherent skiing arena, all skiing accidents were systemically recorded by the two general practitioners for 10 years. The incidence of accidents to children compared with that of adolescents and adults was of particular interest. The incidence of accidents to children has more markedly decreased. The frequency of collisions is increasing. The most common injuries to children are fractures, followed by sprains and contusions. On the other hand sprains are the most common injury to adolescents and adults, followed by fractures and an almost equal number of contusions. The dangers of skiing and the severity of the injuries are discussed. Demands are made for prevention of skiing accidents.

Snow effects on alpine vegetation in the Qinghai-Tibetan Plateau

USGS Publications Warehouse

Wang, Kun; Zhang, Li; Qiu, Yubao; Ji, Lei; Tian, Feng; Wang, Cuizhen; Wang, Zhiyong

2013-01-01

Understanding the relationships between snow and vegetation is important for interpretation of the responses of alpine ecosystems to climate changes. The Qinghai-Tibetan Plateau is regarded as an ideal area due to its undisturbed features with low population and relatively high snow cover. We used 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) datasets during 2001–2010 to examine the snow–vegetation relationships, specifically, (1) the influence of snow melting date on vegetation green-up date and (2) the effects of snow cover duration on vegetation greenness. The results showed that the alpine vegetation responded strongly to snow phenology (i.e., snow melting date and snow cover duration) over large areas of the Qinghai-Tibetan Plateau. Snow melting date and vegetation green-up date were significantly correlated (p < 0.1) in 39.9% of meadow areas (accounting for 26.2% of vegetated areas) and 36.7% of steppe areas (28.1% of vegetated areas). Vegetation growth was influenced by different seasonal snow cover durations (SCDs) in different regions. Generally, the December–February and March–May SCDs played a significantly role in vegetation growth, both positively and negatively, depending on different water source regions. Snow's positive impact on vegetation was larger than the negative impact.

Regional climate models downscaling in the Alpine area with multimodel superensemble

NASA Astrophysics Data System (ADS)

Cane, D.; Barbarino, S.; Renier, L. A.; Ronchi, C.

2013-05-01

The climatic scenarios show a strong signal of warming in the Alpine area already for the mid-XXI century. The climate simulations, however, even when obtained with regional climate models (RCMs), are affected by strong errors when compared with observations, due both to their difficulties in representing the complex orography of the Alps and to limitations in their physical parametrization. Therefore, the aim of this work is to reduce these model biases by using a specific post processing statistic technique, in order to obtain a more suitable projection of climate change scenarios in the Alpine area. For our purposes we used a selection of regional climate models (RCMs) runs which were developed in the framework of the ENSEMBLES project. They were carefully chosen with the aim to maximise the variety of leading global climate models and of the RCMs themselves, calculated on the SRES scenario A1B. The reference observations for the greater Alpine area were extracted from the European dataset E-OBS (produced by the ENSEMBLES project), which have an available resolution of 25 km. For the study area of Piedmont daily temperature and precipitation observations (covering the period from 1957 to the present) were carefully gridded on a 14 km grid over Piedmont region through the use of an optimal interpolation technique. Hence, we applied the multimodel superensemble technique to temperature fields, reducing the high biases of RCMs temperature field compared to observations in the control period. We also proposed the application of a brand new probabilistic multimodel superensemble dressing technique, already applied to weather forecast models successfully, to RCMS: the aim was to estimate precipitation fields, with careful description of precipitation probability density functions conditioned to the model outputs. This technique allowed for reducing the strong precipitation overestimation, arising from the use of RCMs, over the Alpine chain and to reproduce well the monthly behaviour of precipitation in the control period.

A simulation of cross-country skiing on varying terrain by using a mathematical power balance model

PubMed Central

Moxnes, John F; Sandbakk, Øyvind; Hausken, Kjell

2013-01-01

The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%–4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing. PMID:24379718

A simulation of cross-country skiing on varying terrain by using a mathematical power balance model.

PubMed

Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

2013-01-01

The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%-4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing.

Fine Root Abundance and Dynamics of Stone Pine (Pinus cembra) at the Alpine Treeline Is Not Impaired by Self-shading.

PubMed

Kubisch, Petra; Leuschner, Christoph; Coners, Heinz; Gruber, Andreas; Hertel, Dietrich

2017-01-01

Low temperatures are crucial for the formation of the alpine treeline worldwide. Since soil temperature in the shade of tree canopies is lower than in open sites, it was assumed that self-shading may impair the trees' root growth performance. While experiments with tree saplings demonstrate root growth impairment at soil temperatures below 5-7°C, field studies exploring the soil temperature - root growth relationship at the treeline are missing. We recorded soil temperature and fine root abundance and dynamics in shaded and sun-exposed areas under canopies of isolated Pinus cembra trees at the alpine treeline. In contrast to the mentioned assumption, we found more fine root biomass and higher fine root growth in colder than in warmer soil areas. Moreover, colder areas showed higher fine root turnover and thus lower root lifespan than warmer places. We conclude that P. cembra balances enhanced fine root mortality in cold soils with higher fine root activity and by maintaining higher fine root biomass, most likely as a response to shortage in soil resource supply. The results from our study highlight the importance of in situ measurements on mature trees to understand the fine root response and carbon allocation pattern to the thermal growth conditions at the alpine treeline.

Simulated field trip on ski area development

Treesearch

John J. Lindsay; Hubertus J. Mittmann

1979-01-01

Not too long ago winter sports facilities were small and simple. As more people participated in winter sports and technology advanced, the impact on the land in-creased not only from the standpoint of actual facilities needed for winter recreation but also from associated facilities. In many instances winter sports areas developed into full fledged tourist oriented...

Ski Boots

NASA Technical Reports Server (NTRS)

1995-01-01

In cooperation with Raichle Molitor USA Inc. and the international Raichle organization, Comfort Products developed the Raichle Flexon concept in ski boots. The Flexon concept is an adaptation of the accordion-like corrugations of extravehicular space suit joints, which allows ski boots to flex without significant distortion. The design provides immediate transmission of power and therefore precision skiing. Comfort Products also applied heating element circuitry from Apollo astronaut's clothing to foot-warming devices in their boots in the 1970s.

The effects of poling on physiological, kinematic and kinetic responses in roller ski skating.

PubMed

Grasaas, Erik; Hegge, Ann Magdalen; Ettema, Gertjan; Sandbakk, Øyvind

2014-09-01

We investigated the effects of poling on physiological, kinematic and kinetic responses in the G4 skating technique where the poling movement is synchronized with the leg push-off on one side (strong side) followed by a forward arm swing during the leg push-off on the other side (weak side). G4 skating with (G4-P) and without (G4-NP) poling was compared in 17 elite male cross-country skiers during 4-min submaximal tests on a 2% inclined roller ski treadmill at 10, 15 and 20 km h(-1). G4-P demonstrated less ventilatory stress and higher gross efficiency compared to G4-NP at all velocities, and the blood lactate concentration was lower at the high velocity (all P < 0.05). Furthermore, longer cycle lengths and lower cycle rates were found with G4-P at all velocities, with correspondingly lower peak ski forces, increased ski velocities and less angling and edging of the skis (all P < 0.05). The peak ski forces on the strong side were lower than on the weak side with G4-P at all velocities (all P < 0.05), but no differences between the sides were found with G4-NP. The reduced physiological cost, higher gross efficiency and longer cycle lengths together with the lower ski forces at a given work rate with G4-P demonstrate the effectiveness of poling in the G4 skating technique. Thus, poling provides possibilities to increase total propulsion, to reduce ski forces and to enhance skiing efficiency.

How Do World-Class Nordic Combined Athletes Differ From Specialized Cross-Country Skiers and Ski Jumpers in Sport-Specific Capacity and Training Characteristics?

PubMed

Sandbakk, Øyvind; Rasdal, Vegard; Bråten, Steinar; Moen, Frode; Ettema, Gertjan

2016-10-01

To compare sport-specific laboratory capacities and the annual training of world-class Nordic combined (NC) athletes with specialized ski jumpers (SJ) and cross-country (XC) skiers. Five world-class athletes from each sports discipline were compared. Ski jump imitations were performed on a 3-dimensional force plate in NC athletes and SJ, whereas XC skiing characteristics were obtained from submaximal and maximal roller ski skating on a treadmill in NC athletes and XC skiers. In addition, anthropometrics and annual training characteristics were determined. NC athletes demonstrated 9% higher body mass and showed 17% lower vertical speed in the ski jump imitation than SJ (all P < .05). NC athletes had 12% lower body mass and showed 10% lower peak treadmill speed and 12% lower body-mass-normalized peak oxygen uptake than XC skiers (all P < .05). NC athletes performed half the number of ski-jumping-specific sessions and outdoor ski jumps compared with SJ. NC athletes performed 31% less endurance training, mainly caused by lower amounts of low- and moderate-intensity training in the classical technique, whereas high-intensity strength and speed training and endurance training in the skating technique did not differ substantially from XC skiers. To simultaneously optimize endurance, explosive, and technical capacities in 2 different disciplines, world-class NC athletes train approximately two-thirds of the XC skier's endurance training volume and perform one-half of the ski-jump-specific training compared with SJ. Still, the various laboratory capacities differed only 10-17% compared with SJ and XC skiers.

Effects of Planting of Calluna Vulgaris for Stable Snow Accumulation in Winter

NASA Astrophysics Data System (ADS)

Ibuki, R.; Harada, K.

2017-12-01

Recent year climate of the winter season is changing and the period of snow accumulation is reduced compared with before. It affects the management of the ski resort. Snowfall had occurred in December 2016, but the snow accumulated after January 2017 at the ski resort located in the Pacific Ocean side of the Northeast region of Japan. This situation is thought to be originated from two reasons, one is snow thawing, another is to be blown away by the strong monsoon wind. We are considering utilizing planting to stabilize snow accumulation. Currently building rock gardens with shrubs, mainly Calluna Vulgaris in the ski resort for attracting customers in the summer. These are difficult to raise in the lowlands of Japan because they are too hot, but because of their good growth in relatively low-temperature highlands, it is rare for local residents to appreciate the value of these. In addition, it is excellent in low temperature resistance, and it will not die even under the snow. We investigated the pressure resistance performance due to snowfall and the appropriateness of growth under the weather conditions of the area. Regarding Calluna Vulgaris, Firefly, the plants were not damaged even under snow more than 1 m. In addition, three years have passed since planting, relatively good growth is shown, and the stock has been growing every year. Based on these results, we plan to stabilize the snow accumulation by carrying out planting of Calluna vulgaris inside the slope. The growth of the Calluna species is gentle and the tree height grows only about 50 cm even if 15 years have passed since planting. Therefore, it is considered that the plant body is hard to put out their head on the snow surface during the ski season. Next season will monitor the snow accumulation around the planting area through the snow season.

Current challenges in distinguishing climatic and anthropogenic contributions to alpine grassland variation on the Tibetan Plateau.

PubMed

Li, Lanhui; Zhang, Yili; Liu, Linshan; Wu, Jianshuang; Li, Shicheng; Zhang, Haiyan; Zhang, Binghua; Ding, Mingjun; Wang, Zhaofeng; Paudel, Basanta

2018-06-01

Quantifying the impact of climate change and human activities on grassland dynamics is an essential step for developing sustainable grassland ecosystem management strategies. However, the direction and magnitude of climate change and human activities in driving alpine grassland dynamic over the Tibetan Plateau remain under debates. Here, we systematically reviewed the relevant studies on the methods, main conclusions, and causes for the inconsistency in distinguishing the respective contribution of climatic and anthropogenic forces to alpine grassland dynamic. Both manipulative experiments and traditional statistical analysis show that climate warming increase biomass in alpine meadows and decrease in alpine steppes, while both alpine steppes and meadows benefit from an increase in precipitation or soil moisture. Overgrazing is a major factor for the degradation of alpine grassland in local areas with high level of human activity intensity. However, across the entire Tibetan Plateau and its subregions, four views characterize the remaining controversies: alpine grassland changes are primarily due to (1) climatic force, (2) nonclimatic force, (3) combination of anthropogenic and climatic force, or (4) alternation of anthropogenic and climatic force. Furthermore, these views also show spatial inconsistencies. Differences on the source and quality of remote sensing products, the structure and parameter of models, and overlooking the spatiotemporal heterogeneity of human activity intensity contribute to current disagreements. In this review, we highlight the necessity for taking the spatiotemporal heterogeneity of human activity intensity into account in the models of attribution assessment, and the importance for accurate validation of climatic and anthropogenic contribution to alpine grassland variation at multiple scales for future studies.

Warming-induced upslope advance of subalpine forest is severely limited by geomorphic processes

PubMed Central

Macias-Fauria, Marc; Johnson, Edward A.

2013-01-01

Forests are expected to expand into alpine areas because of climate warming, causing land-cover change and fragmentation of alpine habitats. However, this expansion will only occur if the present upper treeline is limited by low-growing season temperatures that reduce plant growth. This temperature limitation has not been quantified at a landscape scale. Here, we show that temperature alone cannot realistically explain high-elevation tree cover over a >100-km2 area in the Canadian Rockies and that geologic/geomorphic processes are fundamental to understanding the heterogeneous landscape distribution of trees. Furthermore, upslope tree advance in a warmer scenario will be severely limited by availability of sites with adequate geomorphic/topographic characteristics. Our results imply that landscape-to-regional scale projections of warming-induced, high-elevation forest advance into alpine areas should not be based solely on temperature-sensitive, site-specific upper-treeline studies but also on geomorphic processes that control tree occurrence at long (centuries/millennia) timescales. PMID:23569221

The long-term trends (1982-2006) in vegetation greenness of the alpine ecosystem in the Qinghai-Tibetan Plateau

USGS Publications Warehouse

Zhang, Li; Guo, Huadong; Wang, Cuizhen; Ji, Lei; Li, Jing; Wang, Kun; Dai, Lin

2014-01-01

The increased rate of annual temperature in the Qinghai-Tibetan Plateau exceeded all other areas of the same latitude in recent decades. The influence of the warming climate on the alpine ecosystem of the plateau was distinct. An analysis of alpine vegetation under changes in climatic conditions was conducted in this study. This was done through an examination of vegetation greenness and its relationship with climate variability using the Advanced Very High Resolution Radiometer satellite imagery and climate datasets. Vegetation in the plateau experienced a positive trend in greenness, with 18.0 % of the vegetated areas exhibiting significantly positive trends, which were primarily located in the eastern and southwestern parts of the plateau. In grasslands, 25.8 % of meadows and 14.1 % of steppes exhibited significant upward trends. In contrast, the broadleaf forests experienced a trend of degradation. Temperature, particularly summer temperature, was the primary factor promoting the vegetation growth in the plateau. The wetter and warmer climate in the east contributed to the favorable conditions for vegetation. The alpine meadow was mostly sensitive to temperature, while the steppes were sensitive to both temperature and precipitation. Although a warming climate was expected to be beneficial to vegetation growth in the alpine region, the rising temperature coupled with reduced precipitation in the south did not favor vegetation growth due to low humidity and poor soil moisture conditions.

The influence of increased distal loading on metabolic cost, efficiency, and kinematics of roller ski skating.

PubMed

Bolger, Conor M; Bessone, Veronica; Federolf, Peter; Ettema, Gertjan; Sandbakk, Øyvind

2018-01-01

The purpose of the present study was to examine the influence of increased loading of the roller ski on metabolic cost, gross efficiency, and kinematics of roller ski skating in steep and moderate terrain, while employing two incline-specific techniques. Ten nationally ranked male cross-country skiers were subjected to four 7-minute submaximal intervals, with 0, 0.5, 1.0, and 1.5 kg added beneath the roller-ski in a randomized order. This was done on two separate days, with the G2 skating at 12% incline and 7 km/h speed and G3 skating at 5% incline and 14 km/h speed, respectively. At 12% incline, there was a significant increase in metabolic rate and a decrease in gross efficiency with added weight (P<0.001 and P = 0.002). At 5% incline, no change in metabolic rate or gross efficiency was found (P = 0.89 and P = 0.11). Rating of perceived exertion (RPE) increased gradually with added weight at both inclines (P>0.05). No changes in cycle characteristics were observed between the different ski loadings at either incline, although the lateral and vertical displacements of the foot/skis were slightly altered at 12% incline with added weight. In conclusion, the present study demonstrates that increased loading of the ski increases the metabolic cost and reduces gross efficiency during steep uphill roller skiing in G2 skating, whereas no significant effect was revealed when skating on relatively flat terrain in G3. Cycle characteristics remained unchanged across conditions at both inclines, whereas small adjustments in the displacement of the foot coincided with the efficiency changes in uphill terrain. The increased RPE values with added ski-weight at both inclines indicates that other factors than those measured here could have influenced effort and/or fatigue when lifting a heavier ski.

Increased expression of c-Ski as a co-repressor in transforming growth factor-beta signaling correlates with progression of esophageal squamous cell carcinoma.

PubMed

Fukuchi, Minoru; Nakajima, Masanobu; Fukai, Yasuyuki; Miyazaki, Tatsuya; Masuda, Norihiro; Sohda, Makoto; Manda, Ryokuhei; Tsukada, Katsuhiko; Kato, Hiroyuki; Kuwano, Hiroyuki

2004-03-01

Transforming growth factor-beta (TGF-beta) regulates cell growth inhibition, and inactivation of the TGF-beta signaling pathway contributes to tumor development. In our previous study, altered expression of TGF-beta, TGF-beta-specific receptors and Smad4 was shown to correlate with tumor progression in esophageal squamous cell carcinoma (SCC). These components, however, were maintained normally in some patients with esophageal SCC. In our study, the mechanism by which aggressive esophageal SCC maintains these components was investigated, with particular emphasis on the participation of c-Ski and SnoN as transcriptional co-repressors in TGF-beta signaling. Immunohistochemistry for c-Ski and SnoN was carried out on surgical specimens obtained from 80 patients with esophageal SCC. The expression of c-Ski and SnoN was also studied in 6 established cell lines derived from esophageal SCC and compared to an immortalized human esophageal cell line by Western blotting. High levels of expression of c-Ski, detected immunohistologically, were found to correlate with depth of invasion (p = 0.0080) and pathologic stage (p = 0.0447). There was, however, no significant correlation between expression of SnoN and clinicopathologic characteristics. A significant correlation between c-Ski and TGF-beta expression was observed. Moreover, in patients with TGF-beta negative expression, the survival rates of patients with c-Ski positive expression were significantly lower than those of patients with c-Ski negative expression (p = 0.0486). c-Ski was expressed at a high level in 5 of 6 cell lines derived from esophageal SCC compared to immortalized esophageal keratinocytes. Furthermore, the cyclin-dependent kinase (CDK) inhibitor, p21 that was up-regulated by TGF-beta signaling was expressed at a low level in the 5 cell lines. The expression of c-Ski protein as a transcriptional co-repressor in TGF-beta signaling seems to be correlated with tumor progression of esophageal SCC. Copyright 2003 Wiley-Liss, Inc.

Biomechanics research in ski jumping, 1991-2006.

PubMed

Schwameder, Hermann

2008-01-01

In this paper, I review biomechanics research in ski jumping with a specific focus on publications presented between 1991 and 2006 on performance enhancement, limiting factors of the take-off, specific training and conditioning, aerodynamics, and safety. The first section presents a brief description of ski jumping phases (in-run, take-off, early flight, stable flight, and landing) regarding the biomechanical and functional fundamentals. The most important and frequently used biomechanical methods in ski jumping (kinematics, ground reaction force analyses, muscle activation patterns, aerodynamics) are summarized in the second section. The third section focuses on ski jumping articles and research findings published after the establishment of the V-technique in 1991, as the introduction of this technique has had a major influence on performance enhancement, ski jumping regulations, and the construction of hill profiles. The final section proposes topics for future research in the biomechanics of ski jumping, including: take-off and early flight and the relative roles of vertical velocity and forward somersaulting angular momentum; optimal jumping patterns utilizing the capabilities of individual athletes; development of kinematic and kinetic feedback systems for hill jumps; comparisons of simulated and hill jumps; effect of equipment modifications on performance and safety enhancement.

The oncoprotein c-ski functions as a direct antagonist of the transforming growth factor-{beta} type I receptor.

PubMed

Ferrand, Nathalie; Atfi, Azeddine; Prunier, Céline

2010-11-01

The oncoprotein c-Ski has been implicated in the negative regulation of transforming growth factor-β (TGF-β) signaling owing to its ability to repress Smad transcriptional activity via recruitment of a transcriptional corepressor complex containing histone deacetylases. However, c-Ski has also been shown to localize to the cytoplasm, raising the interesting possibility that it might disable TGF-β signaling through alternative mechanisms. Here, we provide evidence that c-Ski can restrict TGF-β signaling by interacting directly with the activated TGF-β type I receptor (TβRI). We explored the physiologic relevance of the c-Ski/TβRI interaction and found that it can culminate in a constitutive association of TβRI with a nonfunctional R-Smad/Smad4 complex. Based on these findings, we hypothesize that the interaction between c-Ski and TβRI might interfere with nuclear translocation of the R-Smad/Smad4 complex, thereby attenuating TGF-β signaling. Such a mechanism may play a crucial role in tumor progression, because many tumors that express high levels of c-Ski also display impaired nuclear accumulation of Smads. ©2010 AACR.

Translation Sociology and Social Capital in Rural Development Initiatives. A Case Study from the Italian Alps

ERIC Educational Resources Information Center

Magnani, Natalia; Struffi, Lauro

2009-01-01

This article analyses the results of a European "research and demonstration" project promoting multifunctional and sustainable agriculture in Alpine regions through a participatory approach. It focuses in particular on initiatives undertaken by a local farmers group in the Italian Alpine area of Val di Sole, the purpose being to draw…

Appalachia's Winter Secret: Downhill on the Mountains.

ERIC Educational Resources Information Center

Johnson, Randy

1991-01-01

Describes ski-industry and winter-tourism growth in Appalachia. Sketches ski-resort developments in Maryland, Pennsylvania, North Carolina, and West Virginia. Describes economic threats to industry, its economic impact on Appalachian states and region, resorts' general qualities, and ski industry's promotional efforts. (TES)

14 CFR 27.505 - Ski landing conditions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ski landing conditions. 27.505 Section 27.505 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 27.505 Ski landing...

14 CFR 29.505 - Ski landing conditions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ski landing conditions. 29.505 Section 29.505 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 29.505 Ski landing...

14 CFR 27.505 - Ski landing conditions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ski landing conditions. 27.505 Section 27.505 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 27.505 Ski landing...

14 CFR 29.505 - Ski landing conditions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ski landing conditions. 29.505 Section 29.505 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Ground Loads § 29.505 Ski landing...

Additional Smooth and Rough Water Trials of SKI-CAT.

DTIC Science & Technology

1981-08-01

REPORT & PERIOD COVERED ADDITIONAL SMOOTH AND ROUGH WATER TRIALS OF FINAL SKI- CAT S. PERFORMING ORO. REPORT NUMSER 7. AUTHOR() I. CONTRACT OR GRANT NUMUr...Identif by bloc membe) ’ " -Further tests of SKI- CAT were made in smooth and rough water. Smooth water results confirmed the performance results of...reductions in the accelerations and motions of SKI- CAT over against the head seasreut DD , +A ,3 1473 EDITION OF I NOVS IS OBSOLETE UNCIbSJFIED SIME 0102-014

Nitrogen deposition but not climate warming promotes Deyeuxia angustifolia encroachment in alpine tundra of the Changbai Mountains, Northeast China.

PubMed

Zong, Shengwei; Jin, Yinghua; Xu, Jiawei; Wu, Zhengfang; He, Hongshi; Du, Haibo; Wang, Lei

2016-02-15

Vegetation in the alpine tundra area of the Changbai Mountains, one of two alpine tundra areas in China, has undergone great changes in recent decades. The aggressive herb species Deyeuxia angustifolia (Komarov) Y. L. Chang, a narrow-leaf small reed, was currently encroaching upon the alpine landscape and threatening tundra biota. The alpine tundra of the Changbai Mountains has been experiencing a warmer climate and receiving a high load of atmospheric nitrogen deposition. In this study, we aimed to assess the respective roles of climate warming and atmospheric nitrogen deposition in promoting the upward encroachment of D. angustifolia. We conducted experiments for three years to examine the response of D. angustifolia and a native alpine shrub, Rhododendron chrysanthum, to the conditions in which temperature and nitrogen were increased. Treatments consisting of temperature increase, nitrogen addition, temperature increase combined with nitrogen addition, and controls were conducted on the D. angustifolia communities with three encroachment levels (low, medium, and high levels). Results showed that 1) D. angustifolia grew in response to added nutrients but did not grow well when temperature increased. R. chrysanthum showed negligible responses to the simulated environmental changes. 2) Compared to R. chrysanthum, D. angustifolia could effectively occupy the above-ground space by increasing tillers and growing rapidly by efficiently using nitrogen. The difference in nitrogen uptake abilities between the two species contributed to expansion of D. angustifolia. 3) D. angustifolia encroachment could deeply change the biodiversity of tundra vegetation and may eventually result in the replacement of native biota, especially with nitrogen addition. Our research indicated that nutrient perturbation may be more important than temperature perturbation in promoting D. angustifolia encroachment upon the nutrient- and species-poor alpine tundra ecosystem in the Changbai Mountains. Copyright © 2015 Elsevier B.V. All rights reserved.

Migration, Knowledge Transfer, and the Emergence of Australian Post-War Skiing: The Story of Charles William Anton

PubMed Central

Strobl, Philipp

2016-01-01

Abstract Skiing underwent substantial changes during the post-war years when the sport turned into a multi-billion dollar industry and a leisure activity for the masses. Despite its global nature and popularity, skiing in academic writing has not gained much recognition. This paper explores the role of knowledge transfer during the pioneering phase of post-war skiing in Australia. It describes the life of Charles William Anton, an Austrian refugee from the Anschluss who migrated to Sydney and subsequently became one of the founding fathers of Australian post-war skiing. The following pages show the multi-layered nature of skiing as a global sport by exemplifying how ideas spread from pre-war Europe to post-war Australia. The paper will also provide a case study about refugee knowledge transfer and the ‘productive process of absorption, adoption or rejection of knowledge’ that takes place once an idea has been introduced into a new environment. PMID:29170603

Migration, Knowledge Transfer, and the Emergence of Australian Post-War Skiing: The Story of Charles William Anton.

PubMed

Strobl, Philipp

2016-11-01

Skiing underwent substantial changes during the post-war years when the sport turned into a multi-billion dollar industry and a leisure activity for the masses. Despite its global nature and popularity, skiing in academic writing has not gained much recognition. This paper explores the role of knowledge transfer during the pioneering phase of post-war skiing in Australia. It describes the life of Charles William Anton, an Austrian refugee from the Anschluss who migrated to Sydney and subsequently became one of the founding fathers of Australian post-war skiing. The following pages show the multi-layered nature of skiing as a global sport by exemplifying how ideas spread from pre-war Europe to post-war Australia. The paper will also provide a case study about refugee knowledge transfer and the 'productive process of absorption, adoption or rejection of knowledge' that takes place once an idea has been introduced into a new environment.

SKIV2L Mutations Cause Syndromic Diarrhea, or Trichohepatoenteric Syndrome

PubMed Central

Fabre, Alexandre; Charroux, Bernard; Martinez-Vinson, Christine; Roquelaure, Bertrand; Odul, Egritas; Sayar, Ersin; Smith, Hilary; Colomb, Virginie; Andre, Nicolas; Hugot, Jean-Pierre; Goulet, Olivier; Lacoste, Caroline; Sarles, Jacques; Royet, Julien; Levy, Nicolas; Badens, Catherine

2012-01-01

Syndromic diarrhea (or trichohepatoenteric syndrome) is a rare congenital bowel disorder characterized by intractable diarrhea and woolly hair, and it has recently been associated with mutations in TTC37. Although databases report TTC37 as being the human ortholog of Ski3p, one of the yeast Ski-complex cofactors, this lead was not investigated in initial studies. The Ski complex is a multiprotein complex required for exosome-mediated RNA surveillance, including the regulation of normal mRNA and the decay of nonfunctional mRNA. Considering the fact that TTC37 is homologous to Ski3p, we explored a gene encoding another Ski-complex cofactor, SKIV2L, in six individuals presenting with typical syndromic diarrhea without variation in TTC37. We identified mutations in all six individuals. Our results show that mutations in genes encoding cofactors of the human Ski complex cause syndromic diarrhea, establishing a link between defects of the human exosome complex and a Mendelian disease. PMID:22444670

Releasing Ski-Smad4 mediated suppression is essential to license Th17 differentiation

PubMed Central

Zhang, Song; Takaku, Motoki; Zou, Liyun; Gu, Ai-di; Chou, Wei-chun; Zhang, Ge; Wu, Bing; Kong, Qing; Thomas, Seddon Y.; Serody, Jonathan S.; Chen, Xian; Xu, Xiaojiang; Wade, Paul A.; Cook, Donald N.; Ting, Jenny P.; Wan, Yisong Y.

2017-01-01

Th17 cells are critically involved in host defense, inflammation, and autoimmunity1–5. TGF-β is instrumental in Th17 differentiation by cooperating with IL-66,7. Yet, the mechanism of how TGF-β enables Th17 differentiation remains elusive. Here we reveal that TGF-β licenses Th17 differentiation by releasing Ski-Smad4-complex suppressed RORγt expression. We found serendipitously that, unlike wild-type T cells, Smad4-deficient T cells differentiated into Th17 cells in the absence of TGF-β signaling in a RORγt-dependent manner. Ectopic Smad4 expression suppressed the RORγt expression and Th17 differentiation of Smad4-deficient T cells. Unexpectedly however, TGF-β neutralized Smad4 mediated suppression without affecting Smad4 binding to Rorc locus. Proteomic analysis revealed that Smad4 interacted with Ski, a transcriptional repressor degraded upon TGF-β stimulation. Ski controlled the histone acetylation/de-acetylation of Rorc locus and Th17 differentiation via Smad4 because ectopic Ski expression inhibited H3K9Ac of Rorc locus, Rorc expression and Th17 differentiation in a Smad4-dependent manner. Therefore, TGF-β-induced disruption of Ski releases Ski-Smad4 complex imposed suppression of RORγt to license Th17 differentiation. This study reveals a critical mechanism by which TGF-β controls Th17 differentiation and uncovers Ski-Smad4 axis as a potential therapeutic target for treating Th17 related diseases. PMID:29072299

The Change in the area of various land covers on the Tibetan Plateau during 1957-2015

NASA Astrophysics Data System (ADS)

Cuo, Lan; Zhang, Yongxin

2017-04-01

With average elevation of 4000 m and area of 2.5×106 km2, Tibetan Plateau hosts various fragile ecosystems such as perennial alpine meadow, perennial alpine steppe, temperate evergreen needleleaf trees, temperate deciduous trees, temperate shrub grassland, and barely vegetated desert. Perennial alpine meadow and steppe are the two dominant vegetation types on the heartland of the plateau. MODIS Leaf Area Index (LAI) ranges from 0 to 2 in most part of the plateau. With climate change, these ecosystems are expected to undergo alteration. This study uses a dynamic vegetation model - Lund-Potsdam-Jena (LPJ) to investigate the change of the barely vegetated area and other vegetation types caused by climate change during 1957-2015 on the Tibetan Plateau. Model simulated foliage projective coverage (FPC) and plant functional types (PFTs) are selected for the investigation. The model is evaluated first using both field surveyed land cover map and MODIS LAI images. Long term trends of vegetation FPC is examined. Decadal variations of vegetated and barely vegetated land are compared. The impacts of extreme precipitation, air temperature and CO2 on the expansion and contraction of barely vegetated and vegetated areas are shown. The study will identify the dominant climate factors in affecting the desert area in the region.

Identification of independent storm events: Seasonal and spatial variability of times between storms in Alpine area

NASA Astrophysics Data System (ADS)

Iadanzaa, Carla; Rianna, Maura; Orlando, Dario; Ubertini, Lucio; Napolitano, Francesco

2013-10-01

The aim of the paper is the identification of rain events that trigger landslides through the use of an exponential method to separate stochastic independent events. This activity is carried out within the definition of empirical rainfall thresholds for debris flows and shallow landslides. The study area is the Trento district, which is located in the northeast zone of an Alpine area. The work evaluates the factors that affect the variability in space and time of the critical duration of each rain gauge, defined as the minimum dry period duration that separates two rainy periods that are stochastically independent.

Where do the treeless tundra areas of northern highlands fit in the global biome system: toward an ecologically natural subdivision of the tundra biome.

PubMed

Virtanen, Risto; Oksanen, Lauri; Oksanen, Tarja; Cohen, Juval; Forbes, Bruce C; Johansen, Bernt; Käyhkö, Jukka; Olofsson, Johan; Pulliainen, Jouni; Tømmervik, Hans

2016-01-01

According to some treatises, arctic and alpine sub-biomes are ecologically similar, whereas others find them highly dissimilar. Most peculiarly, large areas of northern tundra highlands fall outside of the two recent subdivisions of the tundra biome. We seek an ecologically natural resolution to this long-standing and far-reaching problem. We studied broad-scale patterns in climate and vegetation along the gradient from Siberian tundra via northernmost Fennoscandia to the alpine habitats of European middle-latitude mountains, as well as explored those patterns within Fennoscandian tundra based on climate-vegetation patterns obtained from a fine-scale vegetation map. Our analyses reveal that ecologically meaningful January-February snow and thermal conditions differ between different types of tundra. High precipitation and mild winter temperatures prevail on middle-latitude mountains, low precipitation and usually cold winters prevail on high-latitude tundra, and Scandinavian mountains show intermediate conditions. Similarly, heath-like plant communities differ clearly between middle latitude mountains (alpine) and high-latitude tundra vegetation, including its altitudinal extension on Scandinavian mountains. Conversely, high abundance of snowbeds and large differences in the composition of dwarf shrub heaths distinguish the Scandinavian mountain tundra from its counterparts in Russia and the north Fennoscandian inland. The European tundra areas fall into three ecologically rather homogeneous categories: the arctic tundra, the oroarctic tundra of northern heights and mountains, and the genuinely alpine tundra of middle-latitude mountains. Attempts to divide the tundra into two sub-biomes have resulted in major discrepancies and confusions, as the oroarctic areas are included in the arctic tundra in some biogeographic maps and in the alpine tundra in others. Our analyses based on climate and vegetation criteria thus seem to resolve the long-standing biome delimitation problem, help in consistent characterization of research sites, and create a basis for further biogeographic and ecological research in global tundra environments.

Varied records of early Wisconsinan alpine glaciation in the western United States derived from weathering-rind thicknesses

USGS Publications Warehouse

Clark, Peter U.; Lea, P.D.

1992-01-01

Weathering-rind thicknesses were measured on volcanic clasts in sequences of glacial deposits in seven mountain ranges in the western United States and in the Puget lowland. Because the rate of rind development decreases with time, ratios of rind thicknesses provide limits on corresponding age ratios. In all areas studied, deposits of late Wisconsinan age are obvious; deposits of late Illinoian age (ca. 140 ka) also seem to be present in each area, although independent evidence for their numerical age is circumstantial. The weathering-rind data indicate that deposits that have intermediate ages between these two are common, and ratios of rind thicknesses suggest an early Wisconsinan age (about 60 to 70 ka) for some of the intermediate deposits. Three of the seven studied alpine areas (McCall, Idaho; Yakima Valley, Washington; and Lassen Peak, California) appear to have early Wisconsinan drift beyond the extent of late Wisconsinan ice. In addition, Mount Rainier and the Puget lowland, Washington, have outwash terraces but no moraines of early Wisconsinan age. The sequences near West Yellowstone, Montana; Truckee, California; and in the southern Olympic Mountains have no recognized moraines or outwash of this age. Many of the areas have deposits that may be of middle Wisconsinan age.Differences in the relative extents of early Wisconsinan alpine glaciers are not expected from the marine oxygen-isotope record and are not explained by any simple trend in climatic variables or proximity to oceanic moisture sources. However, alpine glaciers could have responded more quickly and more variably than continental ice sheets to intense, short-lived climatic events, and they may have been influenced by local climatic or hypsometric effects. The relative sizes of early and late Wisconsinan alpine glaciers could also reflect differences between early and late Wisconsinan continental ice sheets and their regional climatic effects.

Sensitivity of Alpine Snow and Streamflow Regimes to Climate Changes

NASA Astrophysics Data System (ADS)

Rasouli, K.; Pomeroy, J. W.; Marks, D. G.; Bernhardt, M.

2014-12-01

Understanding the sensitivity of hydrological processes to climate change in alpine areas with snow dominated regimes is of paramount importance as alpine basins show both high runoff efficiency associated with the melt of the seasonal snowpack and great sensitivity of snow processes to temperature change. In this study, meteorological data measured in a selection of alpine headwaters basins including Reynolds Mountain East, Idaho, USA, Wolf Creek, Yukon in Canada, and Zugspitze Mountain, Germany with climates ranging from arctic to continental temperate were used to study the snow and streamflow sensitivity to climate change. All research sites have detailed multi-decadal meteorological and snow measurements. The Cold Regions Hydrological Modelling platform (CRHM) was used to create a model representing a typical alpine headwater basin discretized into hydrological response units with physically based representations of snow redistribution by wind, complex terrain snowmelt energetics and runoff processes in alpine tundra. The sensitivity of snow hydrology to climate change was investigated by changing air temperature and precipitation using weather generating methods based on the change factors obtained from different climate model projections for future and current periods. The basin mean and spatial variability of peak snow water equivalent, sublimation loss, duration of snow season, snowmelt rates, streamflow peak, and basin discharge were assessed under varying climate scenarios and the most sensitive hydrological mechanisms to the changes in the different alpine climates were detected. The results show that snow hydrology in colder alpine climates is more resilient to warming than that in warmer climates, but that compensatory factors to warming such as reduced blowing snow sublimation loss and reduced melt rate should also be assessed when considering climate change impacts on alpine hydrology.

Methodological comparison of alpine meadow evapotranspiration on the Tibetan Plateau, China.

PubMed

Chang, Yaping; Wang, Jie; Qin, Dahe; Ding, Yongjian; Zhao, Qiudong; Liu, Fengjing; Zhang, Shiqiang

2017-01-01

Estimation of evapotranspiration (ET) for alpine meadow areas in the Tibetan Plateau (TP) is essential for water resource management. However, observation data has been limited due to the extreme climates and complex terrain of this region. To address these issues, four representative methods, Penman-Monteith (PM), Priestley-Taylor (PT), Hargreaves-Samani (HS), and Mahringer (MG) methods, were adopted to estimate ET, which were then compared with ET measured using Eddy Covariance (EC) for five alpine meadow sites during the growing seasons from 2010 to 2014. And each site was measured for one growing season during this period. The results demonstrate that the PT method outperformed at all sites with a coefficient of determination (R2) ranging from 0.76 to 0.94 and root mean square error (RMSE) ranging from 0.41 to 0.62 mm d-1. The PM method showed better performance than HS and MG methods, and the HS method produced relatively acceptable results with higher R2 (0.46) and lower RMSE (0.89 mm d-1) compared to MG method with R2 of 0.16 and RMSE of 1.62 mm d-1, while MG underestimated ET at all alpine meadow sites. Therefore, the PT method, being the simpler approach and less data dependent, is recommended to estimate ET for alpine meadow areas in the Tibetan Plateau. The PM method produced reliable results when available data were sufficient, and the HS method proved to be a complementary method when variables were insufficient. On the contrary, the MG method always underestimated ET and is, thus, not suitable for alpine meadows. These results provide a basis for estimating ET on the Tibetan Plateau for annual data collection, analysis, and future studies.

Methodological comparison of alpine meadow evapotranspiration on the Tibetan Plateau, China

PubMed Central

Chang, Yaping; Wang, Jie; Qin, Dahe; Ding, Yongjian; Zhao, Qiudong; Liu, Fengjing

2017-01-01

Estimation of evapotranspiration (ET) for alpine meadow areas in the Tibetan Plateau (TP) is essential for water resource management. However, observation data has been limited due to the extreme climates and complex terrain of this region. To address these issues, four representative methods, Penman-Monteith (PM), Priestley-Taylor (PT), Hargreaves-Samani (HS), and Mahringer (MG) methods, were adopted to estimate ET, which were then compared with ET measured using Eddy Covariance (EC) for five alpine meadow sites during the growing seasons from 2010 to 2014. And each site was measured for one growing season during this period. The results demonstrate that the PT method outperformed at all sites with a coefficient of determination (R2) ranging from 0.76 to 0.94 and root mean square error (RMSE) ranging from 0.41 to 0.62 mm d-1. The PM method showed better performance than HS and MG methods, and the HS method produced relatively acceptable results with higher R2 (0.46) and lower RMSE (0.89 mm d-1) compared to MG method with R2 of 0.16 and RMSE of 1.62 mm d-1, while MG underestimated ET at all alpine meadow sites. Therefore, the PT method, being the simpler approach and less data dependent, is recommended to estimate ET for alpine meadow areas in the Tibetan Plateau. The PM method produced reliable results when available data were sufficient, and the HS method proved to be a complementary method when variables were insufficient. On the contrary, the MG method always underestimated ET and is, thus, not suitable for alpine meadows. These results provide a basis for estimating ET on the Tibetan Plateau for annual data collection, analysis, and future studies. PMID:29236754

Fine Root Abundance and Dynamics of Stone Pine (Pinus cembra) at the Alpine Treeline Is Not Impaired by Self-shading

PubMed Central

Kubisch, Petra; Leuschner, Christoph; Coners, Heinz; Gruber, Andreas; Hertel, Dietrich

2017-01-01

Low temperatures are crucial for the formation of the alpine treeline worldwide. Since soil temperature in the shade of tree canopies is lower than in open sites, it was assumed that self-shading may impair the trees’ root growth performance. While experiments with tree saplings demonstrate root growth impairment at soil temperatures below 5–7°C, field studies exploring the soil temperature – root growth relationship at the treeline are missing. We recorded soil temperature and fine root abundance and dynamics in shaded and sun-exposed areas under canopies of isolated Pinus cembra trees at the alpine treeline. In contrast to the mentioned assumption, we found more fine root biomass and higher fine root growth in colder than in warmer soil areas. Moreover, colder areas showed higher fine root turnover and thus lower root lifespan than warmer places. We conclude that P. cembra balances enhanced fine root mortality in cold soils with higher fine root activity and by maintaining higher fine root biomass, most likely as a response to shortage in soil resource supply. The results from our study highlight the importance of in situ measurements on mature trees to understand the fine root response and carbon allocation pattern to the thermal growth conditions at the alpine treeline. PMID:28469633

On the connection of permafrost and debris flow activity in Austria

NASA Astrophysics Data System (ADS)

Huber, Thomas; Kaitna, Roland

2016-04-01

Debris flows represent a severe hazard in alpine regions and typically result from a critical combination of relief energy, water, and sediment. Hence, besides water-related trigger conditions, the availability of abundant sediment is a major control on debris flows activity in alpine regions. Increasing temperatures due to global warming are expected to affect periglacial regions and by that the distribution of alpine permafrost and the depth of the active layer, which in turn might lead to increased debris flow activity and increased interference with human interests. In this contribution we assess the importance of permafrost on documented debris flows in the past by connecting the modeled permafrost distribution with a large database of historic debris flows in Austria. The permafrost distribution is estimated based on a published model approach and mainly depends of altitude, relief, and exposition. The database of debris flows includes more than 4000 debris flow events in around 1900 watersheds. We find that 27 % of watersheds experiencing debris flow activity have a modeled permafrost area smaller than 5 % of total area. Around 7 % of the debris flow prone watersheds have an area larger than 5 %. Interestingly, our first results indicate that watersheds without permafrost experience significantly less, but more intense debris flow events than watersheds with modeled permafrost occurrence. Our study aims to contribute to a better understanding of geomorphic activity and the impact of climate change in alpine environments.

[Vegetation biomass distribution characteristics of alpine tundra ecosystem in Changbai Mountains].

PubMed

Wei, Jing; Wu, Gang; Deng, Hongbing

2004-11-01

Climate change is one of the hotspots in global environment concerns, while alpine tundra ecosystem is most sensitive to global climate change. Because of the relatively small area of tundra, researches on alpine tundra ecosystem were much less. Based on the measurement of species biomass, dominant species organ biomass and vegetation biomass, this paper discussed the biomass spatial variation in alpine tundra ecosystem of Changbai Mountains. The results showed that among 43 species investigated, the first five species in biomass were Rhododendron chrysanthum (159.01 kg x hm(-2)), Vaccinium uliginosum var. alpinum (137.52 kg x hm(-2)), Vaccinium uliginosum (134.7 kg x hm(-2)), Dryas octopetala var. asiatica (131.5 kg x hm(-2)) and Salix rotundifolia (128.4 kg x hm(-2)), which were the dominant species in the alpine tundra ecosystem of Changbai Mountains. Along with increasing altitude, the ratio of below-/above-ground biomass and below-ground/total biomass gradually increased, while the vegetation biomass gradually decreased. The vegetation biomass showed a significant correlation with altitude in typical alpine tundra ecosystem of Changbai Mountains, and the average vegetation biomass was 2.21 t x hm(-2). Alpine tundra ecosystem is very important for microclimate regulation, soil improvement, water-holding, soil conservation, nutrient cycling, carbon fixation and oxygen production, and currently, it is the CO2 sink of Changbai Mountains.

Root biomass along subtropical to alpine gradients: global implication from Tibetan transect studies

Treesearch

Tianxiang Luo; Sandra Brown; Yude Pan; Peili Shi; Hua Ouyang; Zhenliang Yu; Huazhong Zhu

2005-01-01

Much uncertainty in estimating root biomass density (RBD, root mass per unit area) of all roots regionally exists because of methodological difficulties and little knowledge about the effects of biotic and abiotic factors on the magnitude and distribution pattern of RBD. In this study, we collected field data of RBD from 22 sites along the Tibetan Alpine Vegetation...

Geochemistry and petrography of the MacAlpine Hills lunar meteorites

NASA Technical Reports Server (NTRS)

Lindstrom, Marilyn M.; Mckay, David S.; Wentworth, Susan J.; Martinez, Rene R.; Mittlefehldt, David W.; Wang, Ming-Sheng; Lipschutz, Michael E.

1991-01-01

MacAlpine Hills 88104 and 88105, anorthositic lunar meteorites recovered form the same area in Antartica, are characterized. Petrographic studies show that MAC88104/5 is a polymict breccia dominated by impact melt clasts. It is better classified as a fragmental breccia than a regolith breccia. The bulk composition is ferroan and highly aluminous (Al2O3-28 percent).

The increasing incidence of snowboard-related trauma

PubMed Central

Hayes, John R.; Groner, Jonathan I.

2013-01-01

Purpose To investigate injuries among children and adolescents who participate in downhill sports. Methods We collected trauma registry data (January 1999–May 2006) from a level 1 pediatric trauma center with an average snowfall of 28 in (71 cm)/y. Cases were analyzed for injury mechanism, injury type, organ injured, Injury Severity Score, age, sex, and whether or not an operation was required. Results There were 57 snowboarders and 22 skiers admitted during the study period. Forty-one (72%) of snowboarders and 16 (73%) of skiers required operations; 32 (56%) of snowboarders and 9 (41%) of skiers sustained fractures; and 14 (25%) of snowboarders and 6 (27%) of skiers sustained abdominal injuries. (P = NS for all comparisons). Serious splenic injuries were more common in snowboarders (14% vs 4%), but the difference was not statistically significant. All skiing injuries occurred at recreational facilities (commercial skiing areas), whereas 12% of snowboard injuries occurred at home, other residence, or public parks (P = .08). The most striking finding is the rising number of snowboarding injuries and the relatively stable rate of skiing injuries (see graph). Conclusions As the popularity of snowboarding rises, snowboarding injuries in children are increasing. Pediatric surgeons should be wary of the “snowboard spleen.” PMID:18485968

Wintertime slope winds and its turbulent characteristics in the Yeongdong region of Korea

NASA Astrophysics Data System (ADS)

Jeon, H. R.; Eun, S. H.; Kim, B. G.; Lee, Y. H.

2015-12-01

The Yeongdong region has various meteorological phenomenons by virtue of complicated geographical characteristics with high Taebaek Mountains running from the north to the south and an adjacent East Sea to the east. There are few studies on the slope winds and its turbulent characteristics over the complex terrain, which are critical information in mountain climbing, hiking, paragliding, even winter sports such as alpine skiing and ski jump etc. For the understanding of diverse mountain winds in the complex terrain in Yeongdong, hot-wire anemometers (Campbell Scientific) have been installed at a couple of sites since October 2014 and several automatic weather stations at several sites around the mountainous region in Yeongdong since November 2012.WRF model simulations have been also done with an ultra-fine horizontal resolution of 300 m for 10 years. Generally, model and observation show that the dominant wind is westerly, approximately more than 75%. It is quite consistent that wind fields from both model and observation agree with each other in the valley region and at the top of the mountain, but there is a significant disagreement in wind direction specifically in the slide slope. Probably this implies model's performance with even an ultra-fine resolution is still not enough for the slide slope domain of complex terrains. Despite that, the observation clearly showed up- and down slope winds for the weak synoptic conditions carefully selected such as strong insolation and a synoptic wind less than 5m/s in the 850 hPa. The up- and down slope flows are also demonstrated in the snow-covered condition as well as grass ground. Further, planar fit transformation algorithm against the coordinate tilt has been applied to raw wind data (10Hz) of the slope site for the analysis of turbulence properties. Turbulence also increases with synoptic wind strength. Detailed analysis of mechanical turbulence and buoyance will be discussed for different surface properties (grass or snow), and wind strength (weak and strong).

Sports injury and illness epidemiology: Great Britain Olympic Team (TeamGB) surveillance during the Sochi 2014 Winter Olympic Games.

PubMed

Palmer-Green, Debbie; Elliott, Niall

2015-01-01

Sports injury and illness surveillance is the first step in injury and illness prevention, and is important for the protection of both athlete health and performance in major competitions. To identify the prevalence, severity nature and causes of athlete injuries and illnesses in the Great Britain Olympic Team (TeamGB) during the Sochi 2014 Winter Olympic Games. The observational prospective cohort study followed the Great Britain Injury/Illness Performance Project surveillance methodology and obtained information on injuries and illnesses that occurred during the Games between 30 January and 23 February 2014 in TeamGB athletes (n=56). Among the 56 TeamGB athletes, there were 27 injuries and 11 illnesses during the Olympic Games period. This equated to 39% sustaining at least one injury and 18% at least one illness, with an incidence of 48.2 injuries and 19.6 illnesses per 100 athletes, respectively. Of all injuries and illnesses, 9% and 7%, respectively, resulted in time loss. The risk of sustaining an injury was highest for freestyle skiing, skeleton and snowboarding; and lowest for curling, biathlon and Alpine skiing (with no reported injuries); with the lower limb being the most commonly injured location. Respiratory system illnesses were most frequently reported overall, and older female athletes were the ones most affected by illness. The risk of injury was double the risk of illness for TeamGB athletes. Overall, the rate of time-loss issues was low. Methodological considerations are important when interpreting data, and prevention strategies should focus on those issues causing the greatest risk, in terms of prevalence and severity, to athlete health and performance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Notes on Antarctic Aviation

DTIC Science & Technology

1993-08-01

4 5. Curtiss-Wright T -32 biplane used by the second Byrd Antarctic Expedition...pack ice north of Mawson ............................................ 7 10. USN ski-wheel Douglas R4D-8 at McMurdo...McMurdo ................. 11 17. ANARE ski-wheel DHC-2 Beaver over Mawson ............................................ 12 18. USN ski-wheel DHC-3 Otter

Projected climate change impacts on skiing and snowmobiling: A case study of the United States

EPA Science Inventory

A physically-based water and energy balance model is used to simulate natural snow accumulation at 247 winter recreation locations across the continental United States. We combine this model with projections of snowmaking conditions to determine downhill skiing, cross-country ski...

a Study on Mental Representations for Realistic Visualization the Particular Case of Ski Trail Mapping

NASA Astrophysics Data System (ADS)

Balzarini, R.; Dalmasso, A.; Murat, M.

2015-08-01

This article presents preliminary results from a research project in progress that brings together geographers, cognitive scientists, historians and computer scientists. The project investigates the evolution of a particular territorial model: ski trails maps. Ski resorts, tourist and sporting innovations for mountain economies since the 1930s, have needed cartographic representations corresponding to new practices of the space.Painter artists have been involved in producing ski maps with painting techniques and panoramic views, which are by far the most common type of map, because they allow the resorts to look impressive to potential visitors. These techniques have evolved throughout the mutations of the ski resorts. Paper ski maps no longer meet the needs of a large part of the customers; the question now arises of their adaptation to digital media. In a computerized process perspective, the early stage of the project aims to identify the artist-representations, based on conceptual and technical rules, which are handled by users-skiers to perform a task (location, wayfinding, decision-making) and can be transferred to a computer system. This article presents the experimental phase that analyzes artist and user mental representations that are at stake during the making and the reading of a paper ski map. It particularly focuses on how the invention of the artist influences map reading.

Targeting Sphingosine Kinase-1 To Inhibit Melanoma

PubMed Central

Madhunapantula, SubbaRao V.; Hengst, Jeremy; Gowda, Raghavendra; Fox, Todd E.; Yun, Jong K; Robertson, Gavin P.

2012-01-01

SUMMARY Resistance to therapies develops rapidly for melanoma leading to more aggressive disease. Therefore, agents are needed that specifically inhibit proteins or pathways controlling the development of this disease, which can be combined, dependent on genes deregulated in a particular patient’s tumors. This study shows that elevated sphingosine-1-phosphate (S-1-P) levels resulting from increased activity of sphingosine kinase-1 (SPHK1) occur in advanced melanomas. Targeting SPHK1 using siRNA decreased anchorage dependent and independent growth as well as sensitized melanoma cells to apoptosis inducing agents. Pharmacological SPHK1 inhibitors SKI-I but not SKI-II decreased S-1-P content, elevated ceramide levels, caused a G2-M block and induced apoptotic cell death in melanomas. Targeting SPHK1 using siRNA or the pharmacological agent called SKI-I, decreased the levels of pAKT. Furthermore, SKI-I inhibited the expression of CYCLIN D1 protein and increased the activity of caspase-3/7, which in turn led to the degradation of PARP. In animals, SKI-I but not SKI-II retarded melanoma growth by 25-40%. Thus, targeting SPHK1 using siRNAs or SKI-I has therapeutic potential for melanoma treatment either alone or in combination with other targeted agents. PMID:22236408

Three-Dimensional Lower Extremity Joint Loading in a Carved Ski and Snowboard Turn: A Pilot Study

PubMed Central

Müller, Erich

2014-01-01

A large number of injuries to the lower extremity occur in skiing and snowboarding. Due to the difficulty of collecting 3D kinematic and kinetic data with high accuracy, a possible relationship between injury statistic and joint loading has not been studied. Therefore, the purpose of the current study was to compare ankle and knee joint loading at the steering leg between carved ski and snowboard turns. Kinetic data were collected using mobile force plates mounted under the toe and heel part of the binding on skies or snowboard (KISTLER). Kinematic data were collected with five synchronized, panning, tilting, and zooming cameras. An extended version of the Yeadon model was applied to calculate inertial properties of the segments. Ankle and knee joint forces and moments were calculated using inverse dynamic analysis. Results showed higher forces along the longitudinal axis in skiing and similar forces for skiing and snowboarding in anterior-posterior and mediolateral direction. Joint moments were consistently greater during a snowboard turn, but more fluctuations were observed in skiing. Hence, when comparing joint loading between carved ski and snowboard turns, one should differentiate between forces and moments, including the direction of forces and moments and the turn phase. PMID:25317202

The importance of being light: aerodynamic forces and weight in ski jumping.

PubMed

Schmölzer, B; Müller, W

2002-08-01

Many contemporary world class ski jumpers are alarmingly underweight and several cases of anorexia nervosa have come to light. Athletes strive for low body weight because it gives them a major competitive advantage. In order to stop this hazardous development, changes to the regulations are being discussed, and the International Ski Federation and the International Olympic Committee wish to be proactive in safe guarding the interest of the athletes and their health. This study of ski jumping uses field studies conducted during World Cup competitions, large-scale wind tunnel measurements with 1:1 models of ski jumpers in current equipment and highly accurate computer simulations of the flight phase that include the effects due to the athlete's position changes. Particular attention has been directed to the design of a reference jump that mirrors current flight style and equipment regulations (2001), and to the investigation of effects associated with variation in body mass, air density, and wind gusts during the simulated flight. The detailed analysis of the physics of ski jumping described here can be used for the investigation of all initial value and parameter variations that determine the flight path of a ski jumper and will form a reliable basis for setting regulations that will make it less attractive or even disadvantageous for the athlete to be extremely light.

Discovery of Penicillidmus in the Bismarck Archipelago, Papua New Guinea, with description of a new species from Lavongai (New Hanover) Island (Coleoptera, Staphylinidae, Scydmaeninae).

PubMed

Jałoszyński, Paweł

2017-04-18

Penicillidmus Jałoszyński, 2014 was established to accommodate two Australian species of Glandulariini. Penicillidmus masseyensis Jałoszyński, 2014 and P. unicolor Jałoszyński, 2014 are known to occur in Cape York, northern Queensland. With the adult body length ranging from 0.83 to 0.86 mm, these species are among the smallest Australian scydmaenines. Another, yet undescribed species represented by a female, is also known to occur within the same area (Jałoszyński 2014). Penicillidmus resembles similarly small adults of Microscydmus Saulcy & Croissandeau, 1893, but can be easily distinguished on the basis of remarkable cephalic and prothoracic structures. Unlike any other Glandulariini, species of Penicillidmus have a unique system of carinae on the flattened ventral surface of the head, located posterior and lateral to the mouthparts. The submental carina runs along the anterior margin of the submentum and extends laterally along cardinal bases; the longitudinal lateral carina runs at each side of mouthparts and extends from the anterior margin of the head capsule to the 'neck' region; and the transverse carina connects each longitudinal lateral carina with the mesoventral margin of the compound eye. Additionally, the apex of the terminal maxillary palpomere is thickened, and the pronotum bears a thick posterolateral brush of several long setae. The latter character is most easily observable; under a stereomicroscope the brush appears as a solid rod-like structure, individual setae can be recognized in transparent mounts under a compound microscope.

Glacial refugia, recolonization patterns and diversification forces in Alpine-endemic Megabunus harvestmen.

PubMed

Wachter, Gregor A; Papadopoulou, Anna; Muster, Christoph; Arthofer, Wolfgang; Knowles, L Lacey; Steiner, Florian M; Schlick-Steiner, Birgit C

2016-06-01

The Pleistocene climatic fluctuations had a huge impact on all life forms, and various hypotheses regarding the survival of organisms during glacial periods have been postulated. In the European Alps, evidence has been found in support of refugia outside the ice shield (massifs de refuge) acting as sources for postglacial recolonization of inner-Alpine areas. In contrast, evidence for survival on nunataks, ice-free areas above the glacier, remains scarce. Here, we combine multivariate genetic analyses with ecological niche models (ENMs) through multiple timescales to elucidate the history of Alpine Megabunus harvestmen throughout the ice ages, a genus that comprises eight high-altitude endemics. ENMs suggest two types of refugia throughout the last glacial maximum, inner-Alpine survival on nunataks for four species and peripheral refugia for further four species. In some geographic regions, the patterns of genetic variation are consistent with long-distance dispersal out of massifs de refuge, repeatedly coupled with geographic parthenogenesis. In other regions, long-term persistence in nunataks may dominate the patterns of genetic divergence. Overall, our results suggest that glacial cycles contributed to allopatric diversification in Alpine Megabunus, both within and at the margins of the ice shield. These findings exemplify the power of ENM projections coupled with genetic analyses to identify hypotheses about the position and the number of glacial refugia and thus to evaluate the role of Pleistocene glaciations in driving species-specific responses of recolonization or persistence that may have contributed to observed patterns of biodiversity. © 2016 John Wiley & Sons Ltd.

Repression of TGF-beta signaling by the oncogenic protein SKI in human melanomas: consequences for proliferation, survival, and metastasis.

PubMed

Medrano, Estela E

2003-05-19

Transforming growth factor-beta (TGF-beta ) has dual and paradoxical functions as a tumor suppressor and promoter of tumor progression and metastasis. TGF-Ji-mediated growth inhibition is gradually lost during melanoma tumor progression, but there are no measurable defects at the receptor level. Furthermore, melanoma cells release high levels of TGF-beta to the microenvironment, which upon activation induces matrix deposition, angiogenesis, survival, and transition to more aggressive phenotypes. The SKI and SnoN protein family associate with and repress the activity of Smad2, Smad3, and Smad4, three members of the TGF-fl signaling pathway. SKI also facilitates cell-cycle progression by targeting the RB pathway by at least two ways: it directly associates with RB and represses its activity when expressed at high levels, and indirectly, it represses Smad-mediated induction of p21(Waf-1) This results in increased CDK2 activity, RB phosphorylation,and inactivation. Therefore, high levels of SKI result in lesions to the RB pathway in a manner similar to p16 (INK4a) loss. SKI mRNA and protein levels dramatically increase during human melanoma tumor progression. In addition,the SKI protein shifts from nuclear localization in intraepidermal melanoma cells to nuclear and cytoplasmic in invasive and metastatic melanomas. Here, I discuss the basis for repression of intracellular TGF-beta signaling by SKI, some additional activities of this protein, and propose that by disrupting multiple tumor suppressor pathways, SKI functions as a melanoma oncogene.

Behavioral Responses of the Common Bed Bug, Cimex lectularius, to Insecticide Dusts.

PubMed

Agnew, John L; Romero, Alvaro

2017-08-08

Bed bugs have reemerged recently as a serious and growing problem not only in North America but in many parts of the world. These insects have become the most challenging pest to control in urban environments. Residual insecticides are the most common methods used for bed bug control; however, insecticide resistance limits the efficacy of treatments. Desiccant dusts have emerged as a good option to provide a better residual effect for bed bug control. Several studies have focused on determining the efficacy of dust-based insecticides against bed bugs. However, behavioral responses of bed bugs to insecticide dusts could influence their efficacy. The behavioral responses of bed bugs to six insecticide dusts commonly used in the United States were evaluated with an advanced video tracking technique (Ethovision). Bed bugs took longer to make first contact with areas treated with the diatomaceous earth (DE)-based products MotherEarth D and Alpine than pyrethroid, pyrethrins or silica gel based products, DeltaDust, Tempo 1% Dust and CimeXa, respectively. Lower visitation rates of bed bugs were recorded for areas treated with MotherEarth D, Alpine and CimeXa than that of DeltaDust, Tempo 1% Dust, and Tri-Die Silica + Pyrethrum Dust. Bed bugs spent less time in areas treated with Tri-Die Dust, CimeXa, Alpine, and MotherEarth D than DeltaDust and Tempo 1% Dust, and they exhibited a reduction in locomotor parameters when crawling on areas treated with CimeXa and Alpine. The implications of these responses to bed bug control are discussed.

Behavioral Responses of the Common Bed Bug, Cimex lectularius, to Insecticide Dusts

PubMed Central

Agnew, John L.; Romero, Alvaro

2017-01-01

Bed bugs have reemerged recently as a serious and growing problem not only in North America but in many parts of the world. These insects have become the most challenging pest to control in urban environments. Residual insecticides are the most common methods used for bed bug control; however, insecticide resistance limits the efficacy of treatments. Desiccant dusts have emerged as a good option to provide a better residual effect for bed bug control. Several studies have focused on determining the efficacy of dust-based insecticides against bed bugs. However, behavioral responses of bed bugs to insecticide dusts could influence their efficacy. The behavioral responses of bed bugs to six insecticide dusts commonly used in the United States were evaluated with an advanced video tracking technique (Ethovision). Bed bugs took longer to make first contact with areas treated with the diatomaceous earth (DE)-based products MotherEarth D and Alpine than pyrethroid, pyrethrins or silica gel based products, DeltaDust, Tempo 1% Dust and CimeXa, respectively. Lower visitation rates of bed bugs were recorded for areas treated with MotherEarth D, Alpine and CimeXa than that of DeltaDust, Tempo 1% Dust, and Tri-Die Silica + Pyrethrum Dust. Bed bugs spent less time in areas treated with Tri-Die Dust, CimeXa, Alpine, and MotherEarth D than DeltaDust and Tempo 1% Dust, and they exhibited a reduction in locomotor parameters when crawling on areas treated with CimeXa and Alpine. The implications of these responses to bed bug control are discussed. PMID:28786920

Regional Climate Models Downscaling in the Alpine Area with Multimodel SuperEnsemble

NASA Astrophysics Data System (ADS)

Cane, D.; Barbarino, S.; Renier, L.; Ronchi, C.

2012-04-01

The climatic scenarios show a strong signal of warming in the Alpine area already for the mid XXI century. The climate simulation, however, even when obtained with Regional Climate Models (RCMs), are affected by strong errors where compared with observations in the control period, due to their difficulties in representing the complex orography of the Alps and limitations in their physical parametrization. In this work we use a selection of RCMs runs from the ENSEMBLES project, carefully chosen in order to maximise the variety of leading Global Climate Models and of the RCMs themselves, calculated on the SRES scenario A1B. The reference observation for the Greater Alpine Area are extracted from the European dataset E-OBS produced by the project ENSEMBLES with an available resolution of 25 km. For the study area of Piemonte daily temperature and precipitation observations (1957-present) were carefully gridded on a 14-km grid over Piemonte Region with an Optimal Interpolation technique. We applied the Multimodel SuperEnsemble technique to temperature fields, reducing the high biases of RCMs temperature field compared to observations in the control period. We propose also the first application to RCMs of a brand new probabilistic Multimodel SuperEnsemble Dressing technique to estimate precipitation fields, already applied successfully to weather forecast models, with careful description of precipitation Probability Density Functions conditioned to the model outputs. This technique reduces the strong precipitation overestimation by RCMs over the alpine chain and reproduces the monthly behaviour of observed precipitation in the control period far better than the direct model outputs.

Downhill Skiing Injuries.

PubMed

McKay, D H

1981-01-01

In brief: Lower extremity injuries are common in downhill skiing. Fifty-three percent of the skiing injuries in one study, and 81% in another, were below the knee. Twelve case reports are presented and their treatment is discussed. The author suggests that skiers undertake a physical fitness program to increase stamina and elasticity of muscles and ligaments.

Applied Biomechanics Research for the United States Ski Team.

ERIC Educational Resources Information Center

Dillman, Charles J.

1982-01-01

Assisted by a team of physicians and sports scientists, the United States Ski Team has developed its own sports medicine program, the purpose of which is to assist coaches and athletes in controlling and optimizing factors which influence skiing performance. A number of biomechanical research projects which have been undertaken as part of this…

The Evolution of Oscillatory Behavior during Learning on a Ski Simulator

ERIC Educational Resources Information Center

Teulier, Caroline; Nourrit, Deborah; Delignieres, Didier

2006-01-01

Recent experiments on the ski simulator produced ambiguous results and raised unanswered questions concerning the true nature of "novice" behavior and the occurrence of behavioral changes during learning. The aim of the present experiment was to analyze the evolving behavior of three beginners during six practice sessions on a ski simulator. The…

The oncoprotein Ski acts as an antagonist of transforming growth factor-beta signaling by suppressing Smad2 phosphorylation.

PubMed

Prunier, Celine; Pessah, Marcia; Ferrand, Nathalie; Seo, Su Ryeon; Howe, Philip; Atfi, Azeddine

2003-07-11

The phosphorylation of Smad2 and Smad3 by the transforming growth factor (TGF)-beta-activated receptor kinases and their subsequent heterodimerization with Smad4 and translocation to the nucleus form the basis for a model how Smad proteins work to transmit TGF-beta signals. The transcriptional activity of Smad2-Smad4 or Smad3-Smad4 complexes can be limited by the corepressor Ski, which is believed to interact with Smad complexes on TGF-beta-responsive promoters and represses their ability to activate TGF-beta target genes by assembling on DNA a repressor complex containing histone deacetylase. Here we show that Ski can block TGF-beta signaling by interfering with the phosphorylation of Smad2 and Smad3 by the activated TGF-beta type I receptor. Furthermore, we demonstrate that overexpression of Ski induces the assembly of Smad2-Smad4 and Smad3-Smad4 complexes independent of TGF-beta signaling. The ability of Ski to engage Smad proteins in nonproductive complexes provides new insights into the molecular mechanism used by Ski for disabling TGF-beta signaling.

A microcomputer controlled snow ski binding system--I. Instrumentation and field evaluation.

PubMed

MacGregor, D; Hull, M L; Dorius, L K

1985-01-01

This paper presents the design and field evaluation of the first microcomputer controlled ski binding system. This system incorporates an Intel 8086 microcomputer controller and an integral binding/dynamometer. This instrumentation system not only undertakes real time control, but also it records dynamometer data via a miniature digital cassette tape recorder. The integral binding/dynamometer offers the same operational and mounting convenience of commercially available mechanical bindings. The binding may be released either manually or electrically via the controller. Comprised of four octagonal half strain rings, the strain gage dynamometer measures the three moment load components at the boot. To enable the user to conveniently operate the computer, extensive operating software was developed. The operating software is discussed in relation to both the acquisition and storage of data from the dynamometer and the control of the electro-mechanical snow ski binding. The binding system has been used successfully to both record boot moment components and control ski binding release during actual skiing maneuvers. Moment histories typical of three common recreational skiing maneuvers are presented.

Vegetation Changes in the Permafrost Regions of the Qinghai-Tibetan Plateau from 1982-2012: Different Responses Related to Geographical Locations and Vegetation Types in High-Altitude Areas.

PubMed

Wang, Zhiwei; Wang, Qian; Wu, Xiaodong; Zhao, Lin; Yue, Guangyang; Nan, Zhuotong; Wang, Puchang; Yi, Shuhua; Zou, Defu; Qin, Yu; Wu, Tonghua; Shi, Jianzong

2017-01-01

The Qinghai-Tibetan Plateau (QTP) contains the largest permafrost area in a high-altitude region in the world, and the unique hydrothermal environments of the active layers in this region have an important impact on vegetation growth. Geographical locations present different climatic conditions, and in combination with the permafrost environments, these conditions comprehensively affect the local vegetation activity. Therefore, the responses of vegetation to climate change in the permafrost region of the QTP may be varied differently by geographical location and vegetation condition. In this study, using the latest Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) product based on turning points (TPs), which were calculated using a piecewise linear model, 9 areas within the permafrost region of the QTP were selected to investigate the effect of geographical location and vegetation type on vegetation growth from 1982 to 2012. The following 4 vegetation types were observed in the 9 selected study areas: alpine swamp meadow, alpine meadow, alpine steppe and alpine desert. The research results show that, in these study areas, TPs mainly appeared in 2000 and 2001, and almost 55.1% and 35.0% of the TPs were located in 2000 and 2001. The global standardized precipitation evapotranspiration index (SPEI) and 7 meteorological variables were selected to analyze their correlations with NDVI. We found that the main correlative variables to vegetation productivity in study areas from 1982 to 2012 were precipitation, surface downward long-wave radiation and temperature. Furthermore, NDVI changes exhibited by different vegetation types within the same study area followed similar trends. The results show that regional effects rather than vegetation type had a larger impact on changes in vegetation growth in the permafrost regions of the QTP, indicating that climatic factors had a larger impact in the permafrost regions than the environmental factors (including permafrost) related to the underlying surface conditions.

Vegetation Changes in the Permafrost Regions of the Qinghai-Tibetan Plateau from 1982-2012: Different Responses Related to Geographical Locations and Vegetation Types in High-Altitude Areas

PubMed Central

Wu, Xiaodong; Zhao, Lin; Yue, Guangyang; Nan, Zhuotong; Wang, Puchang; Yi, Shuhua; Zou, Defu; Qin, Yu; Wu, Tonghua; Shi, Jianzong

2017-01-01

The Qinghai-Tibetan Plateau (QTP) contains the largest permafrost area in a high-altitude region in the world, and the unique hydrothermal environments of the active layers in this region have an important impact on vegetation growth. Geographical locations present different climatic conditions, and in combination with the permafrost environments, these conditions comprehensively affect the local vegetation activity. Therefore, the responses of vegetation to climate change in the permafrost region of the QTP may be varied differently by geographical location and vegetation condition. In this study, using the latest Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) product based on turning points (TPs), which were calculated using a piecewise linear model, 9 areas within the permafrost region of the QTP were selected to investigate the effect of geographical location and vegetation type on vegetation growth from 1982 to 2012. The following 4 vegetation types were observed in the 9 selected study areas: alpine swamp meadow, alpine meadow, alpine steppe and alpine desert. The research results show that, in these study areas, TPs mainly appeared in 2000 and 2001, and almost 55.1% and 35.0% of the TPs were located in 2000 and 2001. The global standardized precipitation evapotranspiration index (SPEI) and 7 meteorological variables were selected to analyze their correlations with NDVI. We found that the main correlative variables to vegetation productivity in study areas from 1982 to 2012 were precipitation, surface downward long-wave radiation and temperature. Furthermore, NDVI changes exhibited by different vegetation types within the same study area followed similar trends. The results show that regional effects rather than vegetation type had a larger impact on changes in vegetation growth in the permafrost regions of the QTP, indicating that climatic factors had a larger impact in the permafrost regions than the environmental factors (including permafrost) related to the underlying surface conditions. PMID:28068392

Comments on "The Cenozoic fold-and-thrust belt of Eastern Sardinia: Evidences from the integration of field data with numerically balanced geological cross section" by Arragoni et al., 2016

NASA Astrophysics Data System (ADS)

Berra, F.; Lanfranchi, A.; Jadoul, F.

2017-02-01

Arragoni et al. (2016) suggest in their paper published on tectonics that the carbonate succession of Eastern Sardinia represents a Cenozoic fold-and-thrust belt, related to the Alpine orogenesis. According to these authors, this supposed fold-and-thrust belt represents the southward continuation of the Alpine Corsica collisional chain and the missing link between the Alpine Chain and the Calabria-Peloritani domain. Field evidence and the published literature document instead that all the surfaces that Arragoni et al. interpret as thrust are actually stratigraphic contacts. The balanced geological section of Arragoni represents thus a geometric exercise missing the basic data needed to nurse the proposed model, and it does not reflect the geology of Eastern Sardinia. The data provided by Arragoni et al. (2016) do not support the presence of an Alpine thrust-and-fold belt in Eastern Sardinia, and this paper may suggest to the geological community a misleading interpretation of the geodynamic evolution of the Alpine and Mediterranean area.

MiR-34a/miR-93 target c-Ski to modulate the proliferaton of rat cardiac fibroblasts and extracellular matrix deposition in vivo and in vitro.

PubMed

Zhang, Chengliang; Zhang, Yanfeng; Zhu, Hong; Hu, Jiajia; Xie, Zhongshang

2018-06-01

Cardiac fibrosis is associated with diverse heart diseases. In response to different pathological irritants, cardiac fibroblasts may be induced to proliferate and differentiate into cardiac myofibroblasts, thus contributing to cardiac fibrosis. TGF-β signaling is implicated in the development of heart failure through the induction of cardiac fibrosis. C-Ski, an inhibitory regulator of TGF-β signaling, has been reported to suppress TGF-β1-induced human cardiac fibroblasts' proliferation and ECM protein increase; however, the underlying molecular mechanism needs further investigation. In the present study, we demonstrated that c-Ski could ameliorate isoproterenol (ISO)-induced rat myocardial fibrosis model and TGF-β1-induced primary rat cardiac fibroblasts' proliferation, as well as extracellular matrix (ECM) deposition. The protein level of c-Ski was dramatically decreased in cardiac fibrosis and TGF-β1-stimulated primary rat cardiac fibroblasts. In recent decades, a family of small non-coding RNA, namely miRNAs, has been reported to regulate gene expression by interacting with diverse mRNAs and inducing either translational suppression or mRNA degradation. Herein, we selected miR-34a and miR-93 as candidate miRNAs that might target to regulate c-Ski expression. After confirming that miR-34a/miR-93 targeted c-Ski to inhibit its expression, we also revealed that miR-34a/miR-93 affected TGF-β1-induced fibroblasts' proliferation and ECM deposition through c-Ski. Taken together, we demonstrated a miR-34a/miR-93-c-Ski axis which modulates TGF-β1- and ISO-induced cardiac fibrosis in vitro and in vivo; targeting the inhibitory factors of c-Ski to rescue its expression may be a promising strategy for the treatment of cardiac fibrosis. Copyright © 2018 Elsevier Inc. All rights reserved.

Response of rhizosphere soil microbial to Deyeuxia angustifolia encroaching in two different vegetation communities in alpine tundra

NASA Astrophysics Data System (ADS)

Li, Lin; Xing, Ming; Lv, Jiangwei; Wang, Xiaolong; Chen, Xia

2017-02-01

Deyeuxia angustifolia (Komarov) Y. L Chang is an herb species originating from the birch forests in the Changbai Mountain. Recently, this species has been found encroaching into large areas in the western slopes of the alpine tundra in the Changbai Mountain, threatening the tundra ecosystem. In this study, we systematically assessed the response of the rhizosphere soil microbial to D. angustifolia encroaching in alpine tundra by conducting experiments for two vegetation types (shrubs and herbs) by real-time PCR and Illumina Miseq sequencing methods. The treatments consisted of D. angustifolia sites (DA), native sites (NS, NH) and encroaching sites (ES, EH). Our results show that (1) Rhizosphere soil properties of the alpine tundra were significantly impacted by D. angustifolia encroaching; microbial nutrient cycling and soil bacterial communities were shaped to be suitable for D. angustifolia growth; (2) The two vegetation community rhizosphere soils responded differently to D. angustifolia encroaching; (3) By encroaching into both vegetation communities, D. angustifolia could effectively replace the native species by establishing positive plant-soil feedback. The strong adaptation and assimilative capacity contributed to D. angustifolia encroaching in the alpine tundra. Our research indicates that D. angustifolia significantly impacts the rhizosphere soil microbial of the alpine tundra.

Response of rhizosphere soil microbial to Deyeuxia angustifolia encroaching in two different vegetation communities in alpine tundra.

PubMed

Li, Lin; Xing, Ming; Lv, Jiangwei; Wang, Xiaolong; Chen, Xia

2017-02-21

Deyeuxia angustifolia (Komarov) Y. L Chang is an herb species originating from the birch forests in the Changbai Mountain. Recently, this species has been found encroaching into large areas in the western slopes of the alpine tundra in the Changbai Mountain, threatening the tundra ecosystem. In this study, we systematically assessed the response of the rhizosphere soil microbial to D. angustifolia encroaching in alpine tundra by conducting experiments for two vegetation types (shrubs and herbs) by real-time PCR and Illumina Miseq sequencing methods. The treatments consisted of D. angustifolia sites (DA), native sites (NS, NH) and encroaching sites (ES, EH). Our results show that (1) Rhizosphere soil properties of the alpine tundra were significantly impacted by D. angustifolia encroaching; microbial nutrient cycling and soil bacterial communities were shaped to be suitable for D. angustifolia growth; (2) The two vegetation community rhizosphere soils responded differently to D. angustifolia encroaching; (3) By encroaching into both vegetation communities, D. angustifolia could effectively replace the native species by establishing positive plant-soil feedback. The strong adaptation and assimilative capacity contributed to D. angustifolia encroaching in the alpine tundra. Our research indicates that D. angustifolia significantly impacts the rhizosphere soil microbial of the alpine tundra.

Safety knowledge and risk behaviour of injured and uninjured young skiers and snowboarders.

PubMed

Macnab, A J; Cadman, R E; Greenlaw, J V

1998-09-01

Earlier studies of ski injury indicated that youths were at increased risk of injury, that males were most likely to injure the head or face, and that females were most likely to injure the knee. To obtain information about safety knowledge and risk behaviour that might contribute to injury among young skiers and snow-boarders. Survey of knowledge and behaviour in injured and noninjured cohorts. Blackcomb Mountain, Whistler, British Columbia. A total of 863 noninjured and 118 injured skiers and snowboarders aged five to 17 years using Blackcomb during 1993/94. Skier Knowledge Inventory Questionnaire. The injured cohort had less knowledge of the Skiers Responsibility Code. In both groups, almost half had had no lessons, 31% had had bindings adjusted by nonprofessionals and chair lift safety bars were used one ride in four by children age 13 to 17 years. The injuried cohort wore helmets slightly less often. Both groups regularly skied through the trees (60% to 70%), and one-thirds had skied on closed runs. Excessive speed was identified as the major cause of injury. Skiers did not recognize jumping as contributing to injury. Lack of knowledge of safety rules was more prevalent among the injured cohort. Skiing without due care - including skiing through tress, skiing on closed runs, skiing with excessive speed and jumping, particularly by snowboarders - were identified as potential causes of injury.

Dual role of Ski in pancreatic cancer cells: tumor-promoting versus metastasis-suppressive function.

PubMed

Wang, Peng; Chen, Zhen; Meng, Zhi-Qiang; Fan, Jie; Luo, Jian-Min; Liang, Wang; Lin, Jun-Hua; Zhou, Zhen-Hua; Chen, Hao; Wang, Kun; Shen, Ye-Hua; Xu, Zu-De; Liu, Lu-Ming

2009-09-01

Ski used to be defined as an oncogene that contributes to the resistance of tumor cells to transforming growth factor-beta (TGF-beta)-induced growth arrest. As TGF-beta has a dual effect on tumor growth with both tumor-suppressing and -promoting activity depending on the stage of carcinogenesis and the cell type, the precise role of Ski in carcinogenesis remains unclear. In this study, we show that downregulation of Ski through lentivirus-mediated RNA interference decreases tumor growth both in vitro and in vivo, yet promotes cell invasiveness in vitro, and lung metastasis in vivo in the pancreatic cancer cell line SW1990, which contain wild-type Smad4 expression, and the BxPC3 cell line, which is Smad4 deficient. We also show that the downregulation of Ski increases TGF-beta-induced transcriptional activity, which is associated with increased TGF-beta-dependent Smad2/3 phosphorylation, and results in an altered expression profile of TGF-beta-inducible genes involved in metastasis, angiogenesis and cell proliferation and epithelial-mesenchymal transition. Immunohistochemical analysis of specimens from 71 patients with pancreatic adenocarcinoma showed a significant association between overexpression of Ski and decreased patient survival time (P = 0.0024). Our results suggest that Ski may act as a tumor proliferation-promoting factor or as a metastatic suppressor in human pancreatic cancer.

Does listening to music with an audio ski helmet impair reaction time to peripheral stimuli?

PubMed

Ruedl, G; Pocecco, E; Wolf, M; Schöpf, S; Burtscher, M; Kopp, M

2012-12-01

With the recent worldwide increase in ski helmet use, new market trends are developing, including audio helmets for listening to music while skiing or snowboarding. The aim of this study was to evaluate whether listening to music with an audio ski helmet impairs reaction time to peripheral stimuli. A within-subjects design study using the Compensatory-Tracking-Test was performed on 65 subjects (36 males and 29 females) who had a mean age of 23.3 ± 3.9 years. Using repeated measures analysis of variance, we found significant differences in reaction times between the 4 test conditions (p=0.039). The lowest mean reaction time (± SE) was measured for helmet use while listening to music (507.9 ± 13.2 ms), which was not different from helmet use alone (514.6 ± 12.5 ms) (p=0.528). However, compared to helmet use while listening to music, reaction time was significantly longer for helmet and ski goggles used together (535.8 ± 14.2 ms, p=0.005), with a similar trend for helmet and ski goggles used together while listening to music (526.9 ± 13.8 ms) (p=0.094). In conclusion, listening to music with an audio ski helmet did not increase mean reaction time to peripheral stimuli in a laboratory setting. © Georg Thieme Verlag KG Stuttgart · New York.

Enhanced UV exposure on a ski-field compared with exposures at sea level.

PubMed

Allen, Martin; McKenzie, Richard

2005-05-01

Personal erythemal UV monitoring badges, which were developed to monitor the UV exposure of school children, were used to measure UV exposures received by one of the authors (MA) at the Mt Hutt ski-field, in New Zealand. These were then compared with measurements taken at the same times from a nearby sea level site in Christchurch city. The badges were designed to give instantaneous readings of erythemally-weighted (i.e., "sun burning") UV radiation and were cross-calibrated against meteorological grade UV instruments maintained by the National Institute of Water & Atmospheric Research (NIWA). All skiing and calibration days were clear and almost exclusively cloud free. It was found that the UV maxima for horizontal surfaces at the ski-field (altitude approximately 2 km) were 20-30% greater than at the low altitude site. Larger differences between the sites were observed when the sensor was oriented perpendicular to the sun. The personal doses of UV received by a sensor on the skier's lapel during two days of skiing activity were less than those received by a stationary detector on a horizontal surface near sea level. The exposures depended strongly on the time of year, and in mid-October the maximum UV intensity on the ski-field was 60% greater than in mid-September. The UV exposure levels experienced during skiing were smaller than the summer maxima at low altitudes.

77 FR 36994 - Questa Ranger District, Carson National Forest; Taos County, NM; Taos Ski Valley's 2010 Master...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-20

... County, NM; Taos Ski Valley's 2010 Master Development Plan--Phase 1 Projects; Additional Filings AGENCY... environmental impact statement for a proposal to authorize several (Phase 1) projects included in the Taos Ski... (ROD) are expected in July 2012. Change in Responsible Official: In addition, this notice changes the...

Kick, Glide, Pole! Cross-Country Skiing Fun (Part II)

ERIC Educational Resources Information Center

Duoos, Bridget A.

2012-01-01

Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…

Reducing the Odds: Backcountry Powder Skiing in Avalanche Terrain.

ERIC Educational Resources Information Center

Daffern, Tony

This paper provides information and strategies to reduce the risk of encountering an avalanche when skiing or climbing on steep slopes. Skiers must recognize that the risk exists, be aware of their own tolerance for risk, and not allow companions to pressure them into taking more risk than they can tolerate. Ideally, one should ski with a small…

Kick, Glide, Pole! Cross-Country Skiing Fun (Part I)

ERIC Educational Resources Information Center

Duoos, Bridget A.

2011-01-01

Cross-country skiing is a great activity for taking a physical education class outside during the cold winter months. It is also a diverse activity that appeals to students of all ages, and is an excellent cardio-respiratory activity to keep students active. This article has provided the first steps in preparing a cross-country skiing lesson in…

36 CFR 327.30 - Shoreline Management on Civil Works Projects.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Development Areas for ski jumps, floats, boat moorage facilities, duck blinds, and other private floating recreation facilities when they will not create a safety hazard and inhibit public use or enjoyment of project waters or shoreline. A Corps permit is not required for temporary ice fishing shelters or duck...

36 CFR 327.30 - Shoreline Management on Civil Works Projects.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Development Areas for ski jumps, floats, boat moorage facilities, duck blinds, and other private floating recreation facilities when they will not create a safety hazard and inhibit public use or enjoyment of project waters or shoreline. A Corps permit is not required for temporary ice fishing shelters or duck...

Ski Area Recreational Opportunity Enhancement Act of 2011

THOMAS, 112th Congress

Sen. Udall, Mark [D-CO

2011-02-17

Senate - 08/30/2011 Placed on Senate Legislative Calendar under General Orders. Calendar No. 135. (All Actions) Notes: For further action, see H.R.765, which became Public Law 112-46 on 11/7/2011. Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Earth observations taken from orbiter Discovery during STS-85 mission

NASA Image and Video Library

1997-08-11

STS085-716-061 (7 - 19 August 1997) --- The dark green forests of the Sierra Nevada Mts. occupy the left side of the picture. Reno lies between Lake Tahoe (center) and Pyramid Lake (top right). Lake Tahoe, is a clear, deep alpine lake (over 505 meters deep), surrounded by Montane forest, ski resorts and casinos. Although Tahoe is known as one of the clearest lakes in the world, water quality in the lake has been declining due to soil erosion from development. Since 1968, it has lost about 30 feet of clarity. A partnership was recently formed between environmentalists and resort owners to protect their common interest in keeping the lake as clear as possible. Over the last five years they have slowed the erosion and the growth of algae that it causes so that clarity is now "only" lost at a rate of roughly one foot per year. Pyramid Lake (on the upper right of the photo) is as different from Tahoe as a lake could be. The sagebrush desert around the lake and is owned by the Pyramid Lake Paiute tribe who manage it as a fishery for an endangered sucker (fish), the cui-cui. The tribe has added modern fisheries' biology methods to their traditional management and chooses not to develop the lake as a recreation destination. Anaho Island, in the lower half of the lake, is a wildlife refuge managed for American White Pelicans which fly hundreds of miles each day to get from this safe breeding area to the shallow marshes where they feed. Directly above Lake Tahoe is Donner pass, near the site where the beleaguered Donner Party spent the winter of 1846 - 1847 trapped in the mountains. Several shallow ephemeral lakes can be seen in Lemmon Valley north of Reno's core urban area. These lakes would normally have dried up by August when this photo was taken, but are still wet because of the extremely wet winter and floods of January 1997.

Reversing SKI-SMAD4-mediated suppression is essential for TH17 cell differentiation.

PubMed

Zhang, Song; Takaku, Motoki; Zou, Liyun; Gu, Ai-di; Chou, Wei-Chun; Zhang, Ge; Wu, Bing; Kong, Qing; Thomas, Seddon Y; Serody, Jonathan S; Chen, Xian; Xu, Xiaojiang; Wade, Paul A; Cook, Donald N; Ting, Jenny P Y; Wan, Yisong Y

2017-11-02

T helper 17 (T H 17) cells are critically involved in host defence, inflammation, and autoimmunity. Transforming growth factor β (TGFβ) is instrumental in T H 17 cell differentiation by cooperating with interleukin-6 (refs 6, 7). Yet, the mechanism by which TGFβ enables T H 17 cell differentiation remains elusive. Here we reveal that TGFβ enables T H 17 cell differentiation by reversing SKI-SMAD4-mediated suppression of the expression of the retinoic acid receptor (RAR)-related orphan receptor γt (RORγt). We found that, unlike wild-type T cells, SMAD4-deficient T cells differentiate into T H 17 cells in the absence of TGFβ signalling in a RORγt-dependent manner. Ectopic SMAD4 expression suppresses RORγt expression and T H 17 cell differentiation of SMAD4-deficient T cells. However, TGFβ neutralizes SMAD4-mediated suppression without affecting SMAD4 binding to the Rorc locus. Proteomic analysis revealed that SMAD4 interacts with SKI, a transcriptional repressor that is degraded upon TGFβ stimulation. SKI controls histone acetylation and deacetylation of the Rorc locus and T H 17 cell differentiation via SMAD4: ectopic SKI expression inhibits H3K9 acetylation of the Rorc locus, Rorc expression, and T H 17 cell differentiation in a SMAD4-dependent manner. Therefore, TGFβ-induced disruption of SKI reverses SKI-SMAD4-mediated suppression of RORγt to enable T H 17 cell differentiation. This study reveals a critical mechanism by which TGFβ controls T H 17 cell differentiation and uncovers the SKI-SMAD4 axis as a potential therapeutic target for treating T H 17-related diseases.

(124)I-iodopyridopyrimidinone for PET of Abl kinase-expressing tumors in vivo.

PubMed

Doubrovin, Mikhail; Kochetkova, Tatiana; Santos, Elmer; Veach, Darren R; Smith-Jones, Peter; Pillarsetty, Nagavarakishore; Balatoni, Julius; Bornmann, William; Gelovani, Juri; Larson, Steven M

2010-01-01

Because of the recent development of an iodopyridopyrimidinone Abl protein kinase inhibitor (PKI), (124)I-SKI-212230 ((124)I-SKI230), we investigated the feasibility of a PET-based molecular imaging method for the direct visualization of Abl kinase expression and PKI treatment. In vitro pharmacokinetic properties, including specific and nonspecific binding of (124)I-SKI230 to its Abl kinase target and interaction with other PKIs, were assessed in cell-free medium and chronic myelogenous leukemia (CML) cells overexpressing BCR-Abl (K562), in comparison with BT-474 cells that are low in Abl expression. In a xenograft tumor model, we assessed the in vivo pharmacokinetics of (124)I-SKI230 using PET and postmortem tissue sampling. We also tested a paradigm of (124)I-SKI230 PET after treatment of the animal with a dose of Abl-specific PKI for the monitoring of the tumor response. In vitro studies confirmed that SKI230 binds to Abl kinase with nanomolar affinity, that selective uptake occurs in cell lines known to express Abl kinase, that RNAi knock-down supports specificity of cellular uptake due to Abl kinase, and that imatinib, an archetype Abl PKI, completely displaces SKI230. With SKI230, we obtained successful in vivo PET of Abl-expressing human tumors in a nude rat. We were also able to demonstrate evidence of substrate inhibition of in vivo radiotracer uptake in the xenograft tumor after treatment of the animal as a model of PKI treatment monitoring. These results support the hypothesis that molecular imaging using PET will be useful for the study of in vivo pharmacodynamics of Abl PKI molecular therapy in humans.

Effect of climate region and stocking density on ostrich (Struthio camelus) productive performances.

PubMed

Bouyeh, M; Seidavi, A; Mohammadi, H; Sahoo, A; Laudadio, V; Tufarelli, V

2017-02-01

The effects of three climates (hot and dry, mild and humid and Alpine) and three flock densities (<100, 100-300 and >300 m 2 ) on ostrich reproductive and productive traits were studied. Data were compared with the benchmark target sets by the World Ostrich Association (Ostrich benchmark Performance Targets. Version 2, May, 2008) for reproductive qualifications of ostrich. No significant difference was observed on egg production, weight, fertility, hatchability and day-old chicks weight among the three climate conditions; however, the Alpine climate had a lower performance trend. Mild and humid climates had a significant effect of age at sexual maturity for both males and females as well as on the duration of egg production season. Stocking density did not show significant difference on egg production, hatchability, age of male and female at sexual maturity and on duration of egg production season, while an area >300 m 2 showed a reduction in egg weight and day-old chick weight. Further, an area <100 m 2 led to a weaker ostrich fertility rate. Results showed that the ostrich would have a better performance under hot and dry and mild and humid climates as compared to Alpine climate with a stocking density of 100-300 m 2 area per breeder bird. Thus, climatic intervention strategies at Alpine regions may be carried out for maintaining optimal reproductive qualification of ostrich so as to improve the productivity in this sector. © 2016 Blackwell Verlag GmbH.

Frost resistance in alpine woody plants.

PubMed

Neuner, Gilbert

2014-01-01

This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

From Permo-Triassic lithospheric thinning to Jurassic rifting at the Adriatic margin: Petrological and geochronological record in Valtournenche (Western Italian Alps)

NASA Astrophysics Data System (ADS)

Manzotti, Paola; Rubatto, Daniela; Darling, James; Zucali, Michele; Cenki-Tok, Bénédicte; Engi, Martin

2012-08-01

Slices of polycyclic metasediments (marbles and meta-cherts) are tectonically amalgamated with the polydeformed basement of the Dent Blanche tectonic system along a major Alpine shear zone in the Western Alps (Becca di Salé area, Valtournenche Valley). A combination of techniques (structural analysis at various scales, metamorphic petrology, geochronology and trace element geochemistry) was applied to determine the age and composition of accessory phases (titanite, allanite and zircon) and their relation to major minerals. The results are used to reconstruct the polyphase structural and metamorphic histories, comprising both pre-Alpine and Alpine cycles. The pre-Alpine evolution is associated with low-pressure high-temperature metamorphism related to Permo-Triassic lithospheric thinning. In meta-cherts, microtextural relations indicate coeval growth of allanite and garnet during this stage, at ~ 300 Ma. Textures of zircon also indicate crystallisation at HT conditions; ages scatter from 263 to 294 Ma, with a major cluster of data at ~ 276 Ma. In impure marble, U-Pb analyses of titanite domains (with variable Al and F contents) yield apparent 206Pb/238U dates range from Permian to Jurassic. Chemical and isotopic data suggest that titanite formed at Permian times and was then affected by (extension-related?) fluid circulation during the Triassic and Jurassic, which redistributed major elements (Al and F) and partially opened the U-Pb system. The Alpine cycle lead to early blueschist facies assemblages, which were partly overprinted under greenschist facies conditions. The strong Alpine compressional overprint disrupted the pre-Alpine structural imprint and/or reactivated earlier structures. The pre-Alpine metamorphic record, preserved in these slices of metasediments, reflects the onset of the Permo-Triassic lithospheric extension to Jurassic rifting.

Frost resistance in alpine woody plants

PubMed Central

Neuner, Gilbert

2014-01-01

This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone. PMID:25520725

Potential of IMU Sensors in Performance Analysis of Professional Alpine Skiers

PubMed Central

Yu, Gwangjae; Jang, Young Jae; Kim, Jinhyeok; Kim, Jin Hae; Kim, Hye Young; Kim, Kitae; Panday, Siddhartha Bikram

2016-01-01

In this paper, we present an analysis to identify a sensor location for an inertial measurement unit (IMU) on the body of a skier and propose the best location to capture turn motions for training. We also validate the manner in which the data from the IMU sensor on the proposed location can characterize ski turns and performance with a series of statistical analyses, including a comparison with data collected from foot pressure sensors. The goal of the study is to logically identify the ideal location on the skier’s body to attach the IMU sensor and the best use of the data collected for the skier. The statistical analyses and the hierarchical clustering method indicate that the pelvis is the best location for attachment of an IMU, and numerical validation shows that the data collected from this location can effectively estimate the performance and characteristics of the skier. Moreover, placement of the sensor at this location does not distract the skier’s motion, and the sensor can be easily attached and detached. The findings of this study can be used for the development of a wearable device for the routine training of professional skiers. PMID:27043579

Multitemporal analysis of forest fragmentation in Hindu Kush Himalaya-a case study from Khangchendzonga Biosphere Reserve, Sikkim, India.

PubMed

Sharma, Mohit; Areendran, G; Raj, Krishna; Sharma, Ankita; Joshi, P K

2016-10-01

Forests in the mountains are a treasure trove; harbour a large biodiversity; and provide fodder, firewood, timber and non-timber forest products; all of these are essential for human survival in the highest mountains on earth. The present paper attempts a spatiotemporal assessment of forest fragmentation and changes in land use land cover (LULC) pattern using multitemporal satellite data over a time span of around a decade (2000-2009), within the third highest protected area (PA) in the world. The fragmentation analysis using Landscape Fragmentation Tool (LFT) depicts a decrease in large core, edge and patches areas by 5.93, 3.64 and 0.66 %, respectively, while an increase in non-forest and perforated areas by 6.59 and 4.01 %, respectively. The land cover dynamics shows a decrease in open forest, alpine scrub, alpine meadows, snow and hill shadow areas by 2.81, 0.39, 8.18, 3.46 and 0.60 %, respectively, and there is an increase in dense forest and glacier area by 4.79 and 10.65 %, respectively. The change analysis shows a major transformation in areas from open forest to dense forest and from alpine meadows to alpine scrub. In order to quantify changes induced by forest fragmentation and to characterize composition and configuration of LULC mosaics, fragmentation indices were computed using Fragstats at class level, showing the signs of accelerated fragmentation. The outcome of the analysis revealed the effectiveness of geospatial tools coupled with landscape ecology in characterization and quantification of forest fragmentation and land cover changes. The present study provides a baseline database for sustainable conservation planning that will benefit the subsistence livelihoods in the region. Recommendations made based on the present analysis will help to recover forest and halt the pessimistic effects of fragmentation and land cover changes on biodiversity and ecosystem services in the region.

Supervision of School and Youth Groups on Lift-Served Ski Slopes: A Research Perspective

ERIC Educational Resources Information Center

Brookes, Andrew; Holmes, Peter

2014-01-01

Supervised practice is a common feature of many snow sports excursions to downhill ski resorts by school or youth groups, often in combination with lessons from a ski school. What is the role of supervision in preventing mishaps, injury, or fatalities? This article presents results of a search of published snow sports safety research for evidence…

[Changes in skiing accidents during the last 20 years].

PubMed

Röthlisberger, M

1990-01-01

Since 23 years the skiing-accidents are statistically surveyed in the private practice of the author. The number of injured patients is continuously decreasing. Specially the injuries in years with little snow fall are analyzed. It is evident that leg fractures are quite rare but severe injuries of the knee are increasing. 50% of ski accidents are minor injuries.

76 FR 31800 - Airworthiness Directives; Viking Air Limited Model DHC-3 (Otter) Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-02

...: ``Airspeed limitation: VMO = 144 MPH for the effective date of this land/ski plane and VMO = 134 MPH for... limit for land/ in-service (TIS) after the ski plane and 134 MPH, VMO speed limit for seaplane... land/ski the effective date of this plane and/or with a red radial at 134 MPH for a seaplane. This...

[Role of Ski/SnoN protein in the regulation of TGF-beta signal pathway].

PubMed

Lu, Zhao-hui; Chen, Jie

2003-04-01

TGF-beta signal pathway plays an important role in the cell growth, differentiation, formation of extracellular matrix, embryo development and carcinogenesis, etc. However, the regulation of TGF-beta pathway is not totally understood. In 1999, three independent research groups found that Ski/SnoN protein could inhibit the TGF-beta mediated transcription by recruiting N-CoR, a transcription co-repressor. Later studies suggested that TGF-beta and SMADs degraded the Ski/SnoN protein by mediating ubiquitin linkage, showing negative feedback regulation. The important findings in Ski/SnoN laid the theoretical foundation for demonstrating the function of TGF-beta signal pathway.

Skiing economy and efficiency in recreational and elite cross-country skiers.

PubMed

Ainegren, Mats; Carlsson, Peter; Tinnsten, Mats; Laaksonen, Marko S

2013-05-01

The purpose of this study was to investigate and compare skiing economy and gross efficiency in cross-country skiers of different performance levels, ages and genders; male recreational skiers and elite senior and junior cross-country skiers of both genders. The skiers performed tests involving roller skiing on a treadmill using the gear 3 and diagonal stride techniques. The elite cross-country skiers were found to have better skiing economy and higher gross efficiency (5-18%) compared with the recreational skiers (p < 0.05) and the senior elite had better economy and higher efficiency (4-5%) than their junior counterparts (p < 0.05), whereas no differences could be found between the genders. Also, large ranges in economy and gross efficiency were found in all groups. It was concluded that, in addition to V[Combining Dot Above]O2peak, skiing economy and gross efficiency have a great influence on the differences in performance times between recreational and junior and senior elite cross-country skiers, as well as between individual skiers within the different categories. Thus, we recommend cross-country skiers at all performance levels to test not only V[Combining Dot Above]O2peak, but also skiing economy and efficiency.

Fussel-15, a novel Ski/Sno homolog protein, antagonizes BMP signaling.

PubMed

Arndt, Stephanie; Poser, Ina; Moser, Markus; Bosserhoff, Anja-Katrin

2007-04-01

The Ski family of nuclear oncoproteins represses transforming growth factor-beta (TGF-beta) signaling through inhibition of transcriptional activity of Smad proteins. In this study, we identified a novel gene, fussel-15 (functional smad suppressing element on chromosome 15) with high homology to the recently discovered Fussel-18 protein. Both, Fussel-15 and Fussel-18, share important structural features, significant homology and similar genomic organization with the homolog Ski family members, Ski and SnoN. Unlike Ski and SnoN, which are ubiquitously expressed in human tissues, Fussel-15 expression, like Fussel-18, is much more restricted in its expression and is principally found in the nervous system of mouse and humans. Interestingly, Fussel-15 expression is even more restricted in adulthood to Purkinje cells of human cerebellum. In contrast to Fussel-18 that interacts with Smad 2, Smad3 and Smad4 and has an inhibitory activity on TGF-beta signaling, Fussel-15 interacts with Smad1, Smad2 and Smad3 molecules and suppresses mainly BMP signaling pathway but has only minor effects on TGF-beta signaling. This new protein expands the family of Ski/Sno proto-oncoproteins and represents a novel molecular regulator of BMP signaling.

The effects of biotic and abiotic factors on the spatial heterogeneity of alpine grassland vegetation at a small scale on the Qinghai-Tibet Plateau (QTP), China.

PubMed

Wen, Lu; Dong, Shi Kui; Li, Yuan Yuan; Sherman, Ruth; Shi, Jian Jun; Liu, De Mei; Wang, Yan Long; Ma, Yu Shou; Zhu, Lei

2013-10-01

Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation-disturbance-environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai-Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation restoration measures in alpine pastoral regions.

Comparing the impacts of hiking, skiing and horse riding on trail and vegetation in different types of forest.

PubMed

Törn, A; Tolvanen, A; Norokorpi, Y; Tervo, R; Siikamäki, P

2009-03-01

Nature-based tourism in protected areas has increased and diversified dramatically during the last decades. Different recreational activities have a range of impacts on natural environments. This paper reports results from a comparison of the impacts of hiking, cross-country skiing and horse riding on trail characteristics and vegetation in northern Finland. Widths and depths of existing trails, and vegetation on trails and in the neighbouring forests were monitored in two research sites during 2001 and 2002. Trail characteristics and vegetation were clearly related to the recreational activity, research site and forest type. Horse trails were as deep as hiking trails, even though the annual number of users was 150-fold higher on the hiking trails. Simultaneously, cross-country skiing had the least effect on trails due to the protective snow cover during winter. Hiking trail plots had little or no vegetation cover, horse riding trail plots had lower vegetation cover than forest plots, while skiing had no impact on total vegetation cover. On the other hand, on horse riding trails there were more forbs and grasses, many of which did not grow naturally in the forest. These species that were limited to riding trails may change the structure of adjacent plant communities in the long run. Therefore, the type of activities undertaken and the sensitivity of habitats to these activities should be a major consideration in the planning and management of nature-based tourism. Establishment of artificial structures, such as stairs, duckboards and trail cover, or complete closure of the site, may be the only way to protect the most sensitive or deteriorated sites.

Impacts of highway traffic exhaust in alpine valleys on the respiratory health in adults: a cross-sectional study

PubMed Central

2011-01-01

Background Most studies having shown respiratory health effects from traffic exhaust were conducted in urban areas with a complex mixture of air pollution sources. This study has investigated the potential impact of traffic exhaust on respiratory symptoms among adults living along a Swiss alpine highway corridor, where traffic exhaust from the respective trans-Alpine highway is the predominate source of air pollution. Methods In summer 2005, we recruited 1839 adults aged 15 to 70 from a random sample of 10 communities along the Swiss alpine highway corridors. Subjects answered a questionnaire on respiratory health (asthmatic and bronchitic symptoms), risk factors, and potential confounding variables. We used logistic regression models to assess associations between respiratory symptoms and traffic exposure being defined a) as living within 200 m of the highway, and b) as a bell-shaped function simulating the decrease of pollution levels with increasing distance to the highway. Results Positive associations were found between living close to a highway and wheezing without cold (OR = 3.10, 95%-CI: 1.27-7.55) and chronic cough (OR = 2.88, 95%-CI: 1.17-7.05). The models using a bell-shaped function suggested that symptoms reached background levels after 400-500 m from the highway. The association with chronic cough was driven by a subgroup reporting hay fever or allergic rhinitis. Conclusions Highway traffic exhaust in alpine highway corridors, in the absence of other industrial sources, showed negative associations with the respiratory health of adults, higher than those previously found in urban areas. PMID:21371339

Impacts of highway traffic exhaust in alpine valleys on the respiratory health in adults: a cross-sectional study.

PubMed

Hazenkamp-von Arx, Marianne E; Schindler, Christian; Ragettli, Martina S; Künzli, Nino; Braun-Fahrländer, Charlotte; Liu, Lee-Jane S

2011-03-04

Most studies having shown respiratory health effects from traffic exhaust were conducted in urban areas with a complex mixture of air pollution sources. This study has investigated the potential impact of traffic exhaust on respiratory symptoms among adults living along a Swiss alpine highway corridor, where traffic exhaust from the respective trans-Alpine highway is the predominate source of air pollution. In summer 2005, we recruited 1839 adults aged 15 to 70 from a random sample of 10 communities along the Swiss alpine highway corridors. Subjects answered a questionnaire on respiratory health (asthmatic and bronchitic symptoms), risk factors, and potential confounding variables. We used logistic regression models to assess associations between respiratory symptoms and traffic exposure being defined a) as living within 200 m of the highway, and b) as a bell-shaped function simulating the decrease of pollution levels with increasing distance to the highway. Positive associations were found between living close to a highway and wheezing without cold (OR = 3.10, 95%-CI: 1.27-7.55) and chronic cough (OR = 2.88, 95%-CI: 1.17-7.05). The models using a bell-shaped function suggested that symptoms reached background levels after 400-500 m from the highway. The association with chronic cough was driven by a subgroup reporting hay fever or allergic rhinitis. Highway traffic exhaust in alpine highway corridors, in the absence of other industrial sources, showed negative associations with the respiratory health of adults, higher than those previously found in urban areas.

Safety knowledge and risk behaviour of injured and uninjured young skiers and snowboarders

PubMed Central

Macnab, Andrew J; Cadman, Robert E; Greenlaw, Julia V

1998-01-01

BACKGROUND: Earlier studies of ski injury indicated that youths were at increased risk of injury, that males were most likely to injure the head or face, and that females were most likely to injure the knee. OBJECTIVE: To obtain information about safety knowledge and risk behaviour that might contribute to injury among young skiers and snow-boarders. DESIGN: Survey of knowledge and behaviour in injured and noninjured cohorts. SETTING: Blackcomb Mountain, Whistler, British Columbia. PARTICIPANTS: A total of 863 noninjured and 118 injured skiers and snowboarders aged five to 17 years using Blackcomb during 1993/94. INTERVENTION: Skier Knowledge Inventory Questionnaire. RESULTS: The injured cohort had less knowledge of the Skiers Responsibility Code. In both groups, almost half had had no lessons, 31% had had bindings adjusted by nonprofessionals and chair lift safety bars were used one ride in four by children age 13 to 17 years. The injuried cohort wore helmets slightly less often. Both groups regularly skied through the trees (60% to 70%), and one-thirds had skied on closed runs. Excessive speed was identified as the major cause of injury. Skiers did not recognize jumping as contributing to injury. CONCLUSIONS: Lack of knowledge of safety rules was more prevalent among the injured cohort. Skiing without due care – including skiing through tress, skiing on closed runs, skiing with excessive speed and jumping, particularly by snowboarders – were identified as potential causes of injury. PMID:20401273

A reappraisal of success factors for Olympic cross-country skiing.

PubMed

Sandbakk, Øyvind; Holmberg, Hans-Christer

2014-01-01

Cross-country (XC) skiing has been an Olympic event since the first Winter Games in Chamonix, France, in 1924. Due to more effective training and tremendous improvements in equipment and track preparation, the speed of Olympic XC-ski races has increased more than that of any other Olympic endurance sport. Moreover, pursuit, mass-start, and sprint races have been introduced. Indeed, 10 of the 12 current Olympic competitions in XC skiing involve mass starts, in which tactics play a major role and the outcome is often decided in the final sprint. Accordingly, reappraisal of the success factors for performance in this context is required. The very high aerobic capacity (VO2max) of many of today's world-class skiers is similar that of their predecessors. At the same time, the new events provide more opportunities to profit from anaerobic capacity, upper-body power, high-speed techniques, and "tactical flexibility." The wide range of speeds and slopes involved in XC skiing requires skiers to continuously alternate between and adapt different subtechniques during a race. This technical complexity places a premium on efficiency. The relative amounts of endurance training performed at different levels of intensity have remained essentially constant during the past 4 decades. However, in preparation for the Sochi Olympics in 2014, XC skiers are performing more endurance training on roller skis on competition-specific terrain, placing greater focus on upper-body power and more systematically performing strength training and skiing at high speeds than previously.

Are Ski and SnoN Involved in the Tumorigenesis of Oral Squamous Cell Carcinoma Through Smad4?

PubMed

Alaeddini, Mojgan; Etemad-Moghadam, Shahroo

2018-05-04

Transforming growth factor-β has been implicated in the tumorigenesis of oral squamous cell carcinoma (OSCC). Ski and SnoN are negative regulators of transforming growth factor-β/Smad pathway with both prooncogenic and antioncogenic functions in different cancers. The aim of this study was to assess the expression of Ski and SnoN in OSCC for the first time. Smad4 was also evaluated in these tumors. Clinical data on 61 primary OSCCs were gathered, and the specimens were subjected to immunohistochemical staining with monoclonal antibodies against SKI, SnoN, and Smad4 and scored semiquantitatively. Spearman rank, Fisher exact, and χ tests were used for statistical analysis, and P-value <0.05 was considered significant. Ski positivity and SnoN positivity were mostly cytoplasmic and found in 96.7% and 100% of the cases, respectively. Smad4 staining was low to negative in 65% of the specimens. No significant relationship was found either among the markers or between each of the proteins and the clinicopathologic data (P>0.05). According to our findings, Ski, SnoN, and Smad4 seem to play a role in OSCC oncogenesis, and we suggest that Ski and SnoN functions may take place independent of Smad4. Considering the dual and complex role of these proteins in tumorigenesis, further investigation to clarify the molecular pathways involved in their mode of action is suggested.

A Molecular Sensor To Characterize Arenavirus Envelope Glycoprotein Cleavage by Subtilisin Kexin Isozyme 1/Site 1 Protease.

PubMed

Oppliger, Joel; da Palma, Joel Ramos; Burri, Dominique J; Bergeron, Eric; Khatib, Abdel-Majid; Spiropoulou, Christina F; Pasquato, Antonella; Kunz, Stefan

2016-01-15

Arenaviruses are emerging viruses including several causative agents of severe hemorrhagic fevers in humans. The advent of next-generation sequencing technology has greatly accelerated the discovery of novel arenavirus species. However, for many of these viruses, only genetic information is available, and their zoonotic disease potential remains unknown. During the arenavirus life cycle, processing of the viral envelope glycoprotein precursor (GPC) by the cellular subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P) is crucial for productive infection. The ability of newly emerging arenaviruses to hijack human SKI-1/S1P appears, therefore, to be a requirement for efficient zoonotic transmission and human disease potential. Here we implement a newly developed cell-based molecular sensor for SKI-1/S1P to characterize the processing of arenavirus GPC-derived target sequences by human SKI-1/S1P in a quantitative manner. We show that only nine amino acids flanking the putative cleavage site are necessary and sufficient to accurately recapitulate the efficiency and subcellular location of arenavirus GPC processing. In a proof of concept, our sensor correctly predicts efficient processing of the GPC of the newly emergent pathogenic Lujo virus by human SKI-1/S1P and defines the exact cleavage site. Lastly, we employed our sensor to show efficient GPC processing of a panel of pathogenic and nonpathogenic New World arenaviruses, suggesting that GPC cleavage represents no barrier for zoonotic transmission of these pathogens. Our SKI-1/S1P sensor thus represents a rapid and robust test system for assessment of the processing of putative cleavage sites derived from the GPCs of newly discovered arenavirus by the SKI-1/S1P of humans or any other species, based solely on sequence information. Arenaviruses are important emerging human pathogens that can cause severe hemorrhagic fevers with high mortality in humans. A crucial step in productive arenavirus infection of human cells is the processing of the viral envelope glycoprotein by the cellular subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P). In order to break the species barrier during zoonotic transmission and cause severe disease in humans, newly emerging arenaviruses must be able to hijack human SKI-1/S1P efficiently. Here we implement a newly developed cell-based molecular sensor for human SKI-1/S1P to characterize the processing of arenavirus glycoproteins in a quantitative manner. We further use our sensor to correctly predict efficient processing of the glycoprotein of the newly emergent pathogenic Lujo virus by human SKI-1/S1P. Our sensor thus represents a rapid and robust test system with which to assess whether the glycoprotein of any newly emerging arenavirus can be efficiently processed by human SKI-1/S1P, based solely on sequence information. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Geologic and hydrologic hazards in glacierized basins in North America resulting from 19th and 20th century global warming

USGS Publications Warehouse

O'Connor, J. E.; Costa, J.E.

1993-01-01

Alpine glacier retreat resulting from global warming since the close of the Little Ice Age in the 19th and 20th centuries has increased the risk and incidence of some geologic and hydrologic hazards in mountainous alpine regions of North America. Abundant loose debris in recently deglaciated areas at the toe of alpine glaciers provides a ready source of sediment during rainstorms or outburst floods. This sediment can cause debris flows and sedimentation problems in downstream areas. Moraines built during the Little Ice Age can trap and store large volumes of water. These natural dams have no controlled outlets and can fail without warning. Many glacier-dammed lakes have grown in size, while ice dams have shrunk, resulting in greater risks of ice-dam failure. The retreat and thinning of glacier ice has left oversteepened, unstable valley walls and has led to increased incidence of rock and debris avalanches. ?? 1993 Kluwer Academic Publishers.

Spinal injuries in skiers and snowboarders.

PubMed

Tarazi, F; Dvorak, M F; Wing, P C

1999-01-01

Spinal injuries are among the most devastating injuries associated with recreational sports. Snowboarding spinal injury patterns have not been described. During two seasons (1994 to 1995 and 1995 to 1996), 34 skiers and 22 snowboarders suffered serious spinal injuries (fracture or neurologic deficit or both) at two ski areas in British Columbia, Canada. Ski patrol records, the Provincial Trauma Database, and hospital records were reviewed. Injury rates were based on computerized lift-ticket data and a population estimate of 15% snowboarders (ski patrol observation). The incidence of spinal injury among skiers was 0.01 per 1000 skier-days, and among snowboarders was 0.04 per 1000 snowboarder-days. Mean age was 34.5 years for skiers and 22.4 years for snowboarders. Seventy percent of the skiers were men, whereas all of the snowboarders were men. Jumping (intentional jump > 2 meters) was the cause of injury in 20% of skiers and 77% of snowboarders. Neither age nor sex accounted for any significant portion of this difference. The rate of spinal injuries among snowboarders is fourfold that among skiers. Although jumping is the primary cause of injury, it is an intrinsic element of snowboarding. Until research defines effective injury-prevention strategies, knowledge of the risk of snowboarding should be disseminated and techniques for safe jumping should be taught.

Geodiversity and Geoheritage of the Sesia-Val Grande Unesco Geopark (NW-Italy)

NASA Astrophysics Data System (ADS)

Giardino, Marco; Palomba, Mauro; Selvaggio, Ilaria; Ghiraldi, Luca; Giordano, Enrico

2015-04-01

The Sesia-Valgrande Geopark has been founded in September 2013. It is located in the northern sector of Piemonte region covering an area of almost 214000 hectares. In the northern side the Geopark includes the entire territory of the Val Grande National Park, a small portion of the Ossola Valley and the Cannobina valley, while in the south covers most of the mountain range of the Sesia Valley and portions of neighbouring territories such as Valsessera, Prealpi Biellesi, Val Strona and Alte Colline Novaresi. The present morphology of the whole area is characterized by landforms shaped by different geomorphological processes: glacial, hydrological, gravitational and in the south parts also by karstic phenomena. From the geological point of view the Sesia-Val Grande Geopark "rides" the Canavese segment of the Insubric Line, a major tectonic boundary of the Alps. North- and Westward of the Insubric Line, the Austro-Alpine domain consists of piles of nappes, which were assembled and affected by a polymetamorphic event during the Alpine orogeny. South- and Eastward of the Insubric Line, South-Alpine Rock units were not affected by this metamorphic event: they preserve an older history, despite experiencing substantial Alpine tectonic deformation. These are the original rocks of the northern margin of the Adriatic plate, an exceptional record of metamorphic and igneous events preserved with a virtually intact section of the pre-Alpine crust. Beyond geological heritage this territory is one of the most appealing natural environments of the Western Alps, including several different protected areas, important Walser settlement (13th century) and Palaeolithic human traces in the Monte Fenera caves, religious and artistic attraction dominated by the Ghiffa and Varallo Sacred Mount and eventually sport activities such as rafting, hiking, mountaineering and climbing. In order to promote cultural and geological heritage of the area, several scientific institution have been developing different researches and actions both in the scientific and educational domains. The various aspects related to the valorisation and popularization of Cultural Geology have been carried out by Earth Sciences Department of Torino University in cooperation with local institution, in order to enhance the proper management of local geoheritage and the spreading of Earth Science knowledge.

Considerable methane uptake by alpine grasslands despite the cold climate: in situ measurements on the central Tibetan Plateau, 2008-2013.

PubMed

Wei, Da; Xu-Ri; Tenzin-Tarchen; Wang, Yuesi; Wang, Yinghong

2015-02-01

The uptake of CH4 by aerate soil plays a secondary role in the removal of tropospheric CH4 , but it is still highly uncertain in terms of its magnitude, spatial, and temporal variation. In an attempt to quantify the sink of the vast alpine grasslands (1,400,000 km(2)) of the Tibetan Plateau, we conducted in situ measurements in an alpine steppe (4730 m) and alpine meadow (4900 m) using the static chamber and gas chromatograph method. For the alpine steppe, measurements (2008-2013) suggested that there is large interannual variability in CH4 uptake, ranging from -48.8 to -95.8 μg CH4 m(-2) h(-1) (averaged of -71.5 ± 2.5 μg CH4 m(-2) h(-1)), due to the variability in precipitation seasonality. The seasonal pattern of CH4 uptakes in the form of stronger uptake in the early growing season and weaker uptake in the rainy season closely matched the precipitation seasonality and subsequent soil moisture variation. The relationships between alpine steppe CH4 uptake and soil moisture/temperature are best depicted by a quadratic function and an exponential function (Q10 = 1.67) respectively. Our measurements also showed that the alpine meadow soil (average of -59.2 ± 3.7 μg CH4 m(-2) h(-1)) uptake less CH4 than the alpine steppe and produces a similar seasonal pattern, which is negatively regulated by soil moisture. Our measurements quantified--at values far higher than those estimated by process-based models--that both the alpine steppe and alpine meadow are considerable CH4 sinks, despite the cold weather of this high-altitude area. The consecutive measurements gathered in this study also highlight that precipitation seasonality tends to drive the interannual variation in CH4 uptake, indicating that future study should be done to better characterize how CH4 cycling might feedback to the more extreme climate. © 2014 John Wiley & Sons Ltd.

The Effects of Short-Term Ski Trainings on Dynamic Balance Performance and Vertical Jump in Adolescents

ERIC Educational Resources Information Center

Camliguney, Asiye Filiz

2013-01-01

Skiing is a sport where balance and strength are critical and which can be practiced actively especially from early years to old age. The purpose of this study is to examine the effect of a 5-day training of skiing skills on dynamic balance performance and development of vertical jump strength in adolescents. Sixteen adolescent volunteers who do…

Past and future demographic dynamics of alpine species: limited genetic consequences despite dramatic range contraction in a plant from the Spanish Sierra Nevada.

PubMed

Blanco-Pastor, J L; Fernández-Mazuecos, M; Vargas, P

2013-08-01

Anthropogenic global climate change is expected to cause severe range contractions among alpine plants. Alpine areas in the Mediterranean region are of special concern because of the high abundance of endemic species with narrow ranges. This study combined species distribution models, population structure analyses and Bayesian skyline plots to trace the past and future distribution and diversity of Linaria glacialis, an endangered narrow endemic species that inhabits summits of Sierra Nevada (Spain). The results showed that: (i) the habitat of this alpine-Mediterranean species in Sierra Nevada suffered little changes during glacial and interglacial stages of late Quaternary; (ii) climatic oscillations in the last millennium (Medieval Warm Period and Little Ice Age) moderately affected the demographic trends of L. glacialis; (iii) future warming conditions will cause severe range contractions; and (iv) genetic diversity will not diminish at the same pace as the distribution range. As a consequence of the low population structure of this species, genetic impoverishment in the alpine zones of Sierra Nevada should be limited during range contraction. We conclude that maintenance of large effective population sizes via high mutation rates and high levels of gene flow may promote the resilience of alpine plant species when confronted with global warming. © 2013 John Wiley & Sons Ltd.

The effects of grassland degradation on plant diversity, primary productivity, and soil fertility in the alpine region of Asia's headwaters.

PubMed

Wang, Xuexia; Dong, Shikui; Yang, Bing; Li, Yuanyuan; Su, Xukun

2014-10-01

A 3-year survey was conducted to explore the relationships among plant composition, productivity, and soil fertility characterizing four different degradation stages of an alpine meadow in the source region of the Yangtze and Yellow Rivers, China. Results showed that plant species diversity, productivity, and soil fertility of the top 30-cm soil layer significantly declined with degradation stages of alpine meadow over the study period. The productivity of forbs significantly increased with degradation stages, and the soil potassium stock was not affected by grassland degradation. The vegetation composition gradually shifted from perennial graminoids (grasses and sedges) to annual forbs along the degradation gradient. The abrupt change of response in plant diversity, plant productivity, and soil nutrients was demonstrated after heavy grassland degradation. Moreover, degradation can indicate plant species diversity and productivity through changing soil fertility. However, the clear relationships are difficult to establish. In conclusion, degradation influenced ecosystem function and services, such as plant species diversity, productivity, and soil carbon and nitrogen stocks. Additionally, both plant species diversity and soil nutrients were important predictors in different degradation stages of alpine meadows. To this end, heavy degradation grade was shown to cause shift of plant community in alpine meadow, which provided an important basis for sustaining ecosystem function, manipulating the vegetation composition of the area and restoring the degraded alpine grassland.

Factors that Influence the Performance of Elite Sprint Cross-Country Skiers.

PubMed

Hébert-Losier, Kim; Zinner, Christoph; Platt, Simon; Stöggl, Thomas; Holmberg, Hans-Christer

2017-02-01

Sprint events in cross-country skiing are unique not only with respect to their length (0.8-1.8 km), but also in involving four high-intensity heats of ~3 min in duration, separated by a relatively short recovery period (15-60 min). Our aim was to systematically review the scientific literature to identify factors related to the performance of elite sprint cross-country skiers. Four electronic databases were searched using relevant medical subject headings and keywords, as were reference lists, relevant journals, and key authors in the field. Only original research articles addressing physiology, biomechanics, anthropometry, or neuromuscular characteristics and elite sprint cross-country skiers and performance outcomes were included. All articles meeting inclusion criteria were quality assessed. Data were extracted from each article using a standardized form and subsequently summarized. Thirty-one articles met the criteria for inclusion, were reviewed, and scored an average of 66 ± 7 % (range 56-78 %) upon quality assessment. All articles except for two were quasi-experimental, and only one had a fully-experimental research design. In total, articles comprised 567 subjects (74 % male), with only nine articles explicitly reporting their skiers' sprint International Skiing Federation points (weighted mean 116 ± 78). A similar number of articles addressed skating and classical techniques, with more than half of the investigations involving roller-skiing assessments under laboratory conditions. A range of physiological, biomechanical, anthropometric, and neuromuscular characteristics was reported to relate to sprint skiing performance. Both aerobic and anaerobic capacities are important qualities, with the anaerobic system suggested to contribute more to the performance during the first of repeated heats; and the aerobic system during subsequent heats. A capacity for high speed in all the following instances is important for the performance of sprint cross-country skiers: at the start of the race, at any given point when required (e.g., when being challenged by a competitor), and in the final section of each heat. Although high skiing speed is suggested to rely primarily on high cycle rates, longer cycle lengths are commonly observed in faster skiers. In addition, faster skiers rely on different technical strategies when approaching peak speeds, employ more effective techniques, and use better coordinated movements to optimize generation of propulsive force from the resultant ski and pole forces. Strong uphill technique is critical to race performance since uphill segments are the most influential on race outcomes. A certain strength level is required, although more does not necessarily translate to superior sprint skiing performance, and sufficient strength-endurance capacities are also of importance to minimize the impact and accumulation of fatigue during repeated heats. Lastly, higher lean mass does appear to benefit sprint skiers' performance, with no clear advantage conferred via body height and mass. Generalization of findings from one study to the next is challenging considering the array of experimental tasks, variables defining performance, fundamental differences between skiing techniques, and evolution of sprint skiing competitions. Although laboratory-based measures can effectively assess on-snow skiing performance, conclusions drawn from roller-skiing investigations might not fully apply to on-snow skiing performance. A low number of subjects were females (only 17 %), warranting further studies to better understand this population. Lastly, more training studies involving high-level elite sprint skiers and investigations pertaining to the ability of skiers to maintain high-sprint speeds at the end of races are recommended to assist in understanding and improving high-level sprint skiing performance, and resilience to fatigue. Successful sprint cross-country skiing involves well-developed aerobic and anaerobic capacities, high speed abilities, effective biomechanical techniques, and the ability to develop high forces rapidly. A certain level of strength is required, particularly ski-specific strength, as well as the ability to withstand fatigue across the repeated heats of sprint races. Cross-country sprint skiing is demonstrably a demanding and complex sport, where high-performance skiers need to simultaneously address physiological, biomechanical, anthropometric, and neuromuscular aspects to ensure success.

36 CFR § 327.30 - Shoreline Management on Civil Works Projects.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Development Areas for ski jumps, floats, boat moorage facilities, duck blinds, and other private floating recreation facilities when they will not create a safety hazard and inhibit public use or enjoyment of project waters or shoreline. A Corps permit is not required for temporary ice fishing shelters or duck...

Ecological restoration and its effects on a regional climate: the source region of the Yellow River, China.

PubMed

Li, Zhouyuan; Liu, Xuehua; Niu, Tianlin; Kejia, De; Zhou, Qingping; Ma, Tianxiao; Gao, Yunyang

2015-05-19

The source region of the Yellow River, China, experienced degradation during the 1980s and 1990s, but effective ecological restoration projects have restored the alpine grassland ecosystem. The local government has taken action to restore the grassland area since 1996. Remote sensing monitoring results show an initial restoration of this alpine grassland ecosystem with the structural transformation of land cover from 2000 to 2009 as low- and high-coverage grassland recovered. From 2000 to 2009, the low-coverage grassland area expanded by over 25% and the bare soil area decreased by approximately 15%. To examine the relationship between ecological structure and function, surface temperature (Ts) and evapotranspiration (ET) levels were estimated to study the dynamics of the hydro-heat pattern. The results show a turning point in approximately the year 2000 from a declining ET to a rising ET, eventually reaching the 1990 level of approximately 1.5 cm/day. We conclude that grassland coverage expansion has improved the regional hydrologic cycle as a consequence of ecological restoration. Thus, we suggest that long-term restoration and monitoring efforts would help maintain the climatic adjustment functions of this alpine grassland ecosystem.

The Effect of 12 Weeks of Ski Training on Some Biometric Features of Girls

ERIC Educational Resources Information Center

Tas, Murat; Kiyici, Elif; Kiyci, Fatih

2018-01-01

The aim of this study was to investigate the effect of skiing on the biomotoric characteristics of children with evaluating tests of girls between the ages of eight and 14 before and after the season. The experimental group of this study was 15 girls who had just started skiing and the control group of 30 girls. In total, 45 volunteers joined the…

Kinematics and Kinetics of Squats, Drop Jumps and Imitation Jumps of Ski Jumpers.

PubMed

Pauli, Carole A; Keller, Melanie; Ammann, Fabian; Hübner, Klaus; Lindorfer, Julia; Taylor, William R; Lorenzetti, Silvio

2016-03-01

Squats, drop jumps, and imitation jumps are commonly used training exercises in ski jumping to enhance maximum force, explosive force, and sport-specific skills. The purpose of this study was to evaluate the kinetics and kinematics of training exercises in ski jumping and to find objective parameters in training exercises that most correlate with the competition performance of ski jumpers. To this end, barbell squats, drop jumps, and imitation jumps were measured in a laboratory environment for 10 elite ski jumpers. Force and motion data were captured, and the influence of maximum vertical force, force difference, vertical take-off velocity, knee moments, knee joint power, and a knee valgus/varus index was evaluated and correlated with their season jump performance. The results indicate that, especially for the imitation jumps, a good correlation exists between the vertical take-off velocity and the personal jump performance on the hill (R = 0.718). Importantly, however, the more the athletes tended toward a valgus knee alignment during the measured movements, the worse their performance (R = 0.729 imitation jumps; R = 0.685 squats). Although an evaluation of the athletes' lower limb alignment during competitive jumping on the hill is still required, these preliminary data suggest that performance training should additionally concentrate on improving knee alignment to increase ski jumping performance.

Abiotic and biotic controls of spatial pattern at alpine treeline

USGS Publications Warehouse

Malanson, George P.; Xiao, Ningchuan; Alftine, K.J.; Bekker, Mathew; Butler, David R.; Brown, Daniel G.; Cairns, David M.; Fagre, Daniel; Walsh, Stephen J.

2000-01-01

At alpine treeline, trees and krummholz forms affect the environment in ways that increase their growth and reproduction. We assess the way in which these positive feedbacks combine in spatial patterns to alter the environment in the neighborhood of existing plants. The research is significant because areas of alpine tundra are susceptible to encroachment by woody species as climate changes. Moreover, understanding the general processes of plant invasion is important. The importance of spatial pattern has been recognized, but the spatial pattern of positive feedbacks per se has not been explored in depth. We present a linked set of models of vegetation change at an alpine forest-tundra ecotone. Our aim is to create models that are as simple as possible in order to test specific hypotheses. We present results from a model of the resource averaging hypothesis and the positive feedback switch hypothesis of treelines. We compare the patterns generated by the models to patterns observed in fine scale remotely sensed data.

Influence of Slope-Scale Snowmelt on Catchment Response Simulated With the Alpine3D Model

NASA Astrophysics Data System (ADS)

Brauchli, Tristan; Trujillo, Ernesto; Huwald, Hendrik; Lehning, Michael

2017-12-01

Snow and hydrological modeling in alpine environments remains challenging because of the complexity of the processes affecting the mass and energy balance. This study examines the influence of snowmelt on the hydrological response of a high-alpine catchment of 43.2 km2 in the Swiss Alps during the water year 2014-2015. Based on recent advances in Alpine3D, we examine how snow distributions and liquid water transport within the snowpack influence runoff dynamics. By combining these results with multiscale observations (snow lysimeter, distributed snow depths, and streamflow), we demonstrate the added value of a more realistic snow distribution at the onset of melt season. At the site scale, snowpack runoff is well simulated when the mass balance errors are corrected (R2 = 0.95 versus R2 = 0.61). At the subbasin scale, a more heterogeneous snowpack leads to a more rapid runoff pulse originating in the shallower areas while an extended melting period (by a month) is caused by snowmelt from deeper areas. This is a marked improvement over results obtained using a traditional precipitation interpolation method. Hydrological response is also improved by the more realistic snowpack (NSE of 0.85 versus 0.74), even though calibration processes smoothen out the differences. The added value of a more complex liquid water transport scheme is obvious at the site scale but decreases at larger scales. Our results highlight not only the importance but also the difficulty of getting a realistic snowpack distribution even in a well-instrumented area and present a model validation from multiscale experimental data sets.

Stretch-shortening cycle in roller ski skating: effects of technique.

PubMed

Perrey, S; Millet, G Y; Candau, R; Rouillon, J D

1998-11-01

The purposes of this study were 1) to examine the occurrence of the stretch-shortening cycle (SSC) in the three principal techniques of ski skating and 2) to test the hypothesis that differences in SSC behaviour may explain the choice of a technique when the grade is altered. Ten highly skilled male cross-country skiers roller skied at 5.3+/-0.1 m x s(-1) using the V1 skate (V1), V2-alternate (V2A), and V2 skate (V2) techniques. Knee and ankle joint kinematics, EMG of the vastus lateralis (VL) and gastrocnemius lateralis (GL) muscles, and roller ski velocity were recorded during the last 40 s of each bout of roller skiing. The existence of an EMG signal during the eccentric phase prior to the thrust, as well as the lack of significant delay between the two phases, showed that SSC occurs in the three techniques of roller ski skating with the exception of 50% of the subjects at the weak side knee with V1. The VL stretching velocity over the eccentric phase was higher (p < 0.005) with V2 and V2A than V1, indicating that less elastic energy was stored in the lower limbs extensor muscles with V1. This could partly explain why this technique is not used on flat terrains during races. However, no differences of average EMG activity or IEMG existed between techniques for either GL or VL during the concentric phase, suggesting that the theoretical advantage due to the SSC behaviour is minor in roller ski skating.

Kinematics and Kinetics of Squats, Drop Jumps and Imitation Jumps of Ski Jumpers

PubMed Central

Pauli, Carole A.; Keller, Melanie; Ammann, Fabian; Hübner, Klaus; Lindorfer, Julia; Taylor, William R.

2016-01-01

Abstract Pauli, CA, Keller, M, Ammann, F, Hübner, K, Lindorfer, J, Taylor, WR, and Lorenzetti, S. Kinematics and kinetics of squats, drop jumps and imitation jumps of ski jumpers. J Strength Cond Res 30(3): 643–652, 2016—Squats, drop jumps, and imitation jumps are commonly used training exercises in ski jumping to enhance maximum force, explosive force, and sport-specific skills. The purpose of this study was to evaluate the kinetics and kinematics of training exercises in ski jumping and to find objective parameters in training exercises that most correlate with the competition performance of ski jumpers. To this end, barbell squats, drop jumps, and imitation jumps were measured in a laboratory environment for 10 elite ski jumpers. Force and motion data were captured, and the influence of maximum vertical force, force difference, vertical take-off velocity, knee moments, knee joint power, and a knee valgus/varus index was evaluated and correlated with their season jump performance. The results indicate that, especially for the imitation jumps, a good correlation exists between the vertical take-off velocity and the personal jump performance on the hill (R = 0.718). Importantly, however, the more the athletes tended toward a valgus knee alignment during the measured movements, the worse their performance (R = 0.729 imitation jumps; R = 0.685 squats). Although an evaluation of the athletes' lower limb alignment during competitive jumping on the hill is still required, these preliminary data suggest that performance training should additionally concentrate on improving knee alignment to increase ski jumping performance. PMID:26418370

A comparison of wakeboard-, water skiing-, and tubing-related injuries in the United States, 2000-2007.

PubMed

Baker, John I; Griffin, Russell; Brauneis, Paul F; Rue, Loring W; McGwin, Gerald

2010-01-01

The purpose of the study was to compare tubing-related injuries to wakeboarding- and water skiing-related injuries. Data was collected from the 2000-2007 National Electronic Injury Surveillance Survey for 1,761 individuals seeking care at an emergency department due to a tubing-, wakeboarding, or water skiing-related injury. Data included patient age and sex, as well as injury characteristics including body region injured (i.e., head and neck, trunk, shoulder and upper extremity, and hip and lower extremity) and diagnosis of injury (e.g., contusion, laceration, or fracture). Case narratives were reviewed to ensure that a tubing-, wakeboarding-, or water skiing-related injury occurred while the individual was being towed behind a boat. Severe injury (defined as an injury resulting in the individual being hospitalized, transferred, held for observation) was compared among the groups using logistic regression. Wakeboard- and tubing-related injuries more commonly involved the head and neck, while water skiing- related injuries were likely to involve the hip and lower extremity. Tubing-related injuries, compared to water skiing-related injuries, were more likely to be severe (OR 2.31, 95% CI 1.23-4. 33). Like wakeboarding and water skiing, tubing has inherent risks that must be understood by the participant. While tubing is generally considered a safer alternative to wakeboarding and water skiing, the results of the current study suggest otherwise. Both the number and severity of tubing- related injuries could be prevented through means such as advocating the use of protective wear such as helmets while riding a tube or having recommended safe towing speeds prominently placed on inner tubes. Key pointsIncrease annual injury rate trend in wakeboard injuries.Wakeboard- and tubing-related injuries more often to head and neck, waterskiing-related injuries more often to hip and lower extremity.Tubing-related injuries over 2-times as likely to be severe compared to waterskiing-related injuries.

Yeast RNA viruses as indicators of exosome activity: human exosome hCsl4p participates in RNA degradation in Saccharomyces cerevisiae'.

PubMed

Ramírez-Garrastacho, Manuel; Esteban, Rosa

2011-12-01

The exosome is an evolutionarily conserved 10-mer complex involved in RNA metabolism, located in both the nucleus and the cytoplasm. The cytoplasmic exosome plays an important role in mRNA turnover through its 3'→5' exonucleolytic activity. The superkiller (SKI) phenotype of yeast was originally identified as an increase of killer toxin production due to elevated levels of the L-A double-stranded RNA (dsRNA) Totivirus and its satellite toxin-encoding M dsRNA. Most SKI genes were later shown to be either components of the exosome or modulators of its activity. Variations in the amount of Totivirus are, thus, good indicators of yeast exosome activity, and can be used to analyse its components. Furthermore, if exosome proteins of higher eukaryotes were functional in S. cerevisiae, these viruses would provide a simple tool to analyse their function. In this work, we have found that hCSL4, the human orthologue of SKI4 in the yeast exosome, rescues the null phenotype of the deletion mutant. hCsl4p shares with Ski4p conserved S1 RNA-binding domains, but lacks the N-terminal third of Ski4p. Nevertheless, it interacts with the Dis3p exonuclease of yeast exosome, and partially complements the superkiller phenotype of ski4-1 mutation. The elimination of the N-terminal third of Ski4p does not affect its activity, indicating that it is dispensable for RNA degradation. We have also identified the point mutation G152E in hCSL4, equivalent to the ski4-1 mutation G253E, which impairs the activity of the protein, thus validating our approach of using yeast RNA virus to analyse the exosome of higher eukaryotes. Copyright © 2011 John Wiley & Sons, Ltd.

Compliance with Sunscreen Advice in a Survey of Adults Engaged in Outdoor Winter Recreation at High Elevation Ski Areas

PubMed Central

Buller, David B.; Andersen, Peter A.; Walkosz, Barbara J.; Scott, Michael D.; Maloy, Julie A.; Dignan, Mark B.; Cutter, Gary R.

2010-01-01

Background Adults are advised to wear sunscreen with a sun protection factor of 15+, apply it up to 30 minutes prior to sun exposure, and reapply it after two hours to reduce exposure to ultraviolet (UV) radiation in sunlight for the prevention of skin cancer. Objective This study investigated the extent to which adults comply with sunscreen advice. Methods A survey was conducted with 4,837 adult skiers and snowboarders at 28 high-altitude ski areas in Western North America in January – April 2001-02. Respondents self reported use of sunscreen, its SPF, time of first application, and reapplication. Results Only 4.4% (95% CI=±0.6) of adults were in full compliance with all sunscreen advice. Half (49.8% [95% CI=±1.4]) complied with SPF 15+ advice. Of those wearing sunscreen, 73.2% (95% CI=±1.8) applied the sunscreen 30 minutes before beginning skiing/snowboarding, but only 20.4% (95% CI=±2.0) complied with advice to reapply it after 2 hours. Total compliance was lowest during inclement weather, on low-UV days, by males, and among respondents who believed skin cancer was unimportant and with low sun sensitive skin. It was positively associated with wearing lip balm and hats with a brim. Limitations The sample was predominantly male and of high socio-economic status; the results apply most to winter recreation when UV radiation levels are low, and sunscreen use was assessed by self-report. Conclusion While the recommendation to use SPF 15+ sunscreen has reached many adults, the reapplication advice is heeded by few adults and needs to be highlighted in future sun safety promotions. PMID:21742410

Crustal Structure and Seismicity along the Central Alpine Fault: Results from the WIZARD Array

NASA Astrophysics Data System (ADS)

Thurber, C. H.; Roecker, S. W.; Townend, J.; Bannister, S. C.; Guo, B.; Rawles, C.; Feenstra, J. P.

2015-12-01

In 2012 and 2013, the University of Wisconsin-Madison (UW), Rensselaer Polytechnic Institute (RPI), and Victoria University of Wellington (VUW) operated a 20-station temporary seismic array along the obliquely slipping Alpine Fault on the South Island of New Zealand. The stations of the array, nicknamed WIZARD, were deployed mainly north and east of the Deep Fault Drilling Program (DFDP) borehole site in Whataroa Valley (DFPD-2). WIZARD complemented the station distribution of the Southern Alps Microearthquake Borehole Array (SAMBA) operated by VUW, situated south and west of DFDP-2. Three additional temporary stations were deployed to the north and east of WIZARD by GNS Science, and four GeoNet permanent stations fell within the footprint of our study area. The main goals of the WIZARD project are to image the crustal structure in the region surrounding the DFDP-2 site, relocate earthquakes as precisely and accurately as possible, and determine focal mechanisms for the larger earthquakes, in order to characterize the Alpine Fault and its geometry at depth. Some previous studies had identified the area covered by WIZARD to be largely aseismic, but we have in fact located roughly 500 earthquakes underneath WIZARD. A new automatic S-wave picker proved to be very effective for rapidly increasing the size of our S-wave arrival dataset. Our tomographic inversion results show that significant velocity contrasts in both Vp and Vs (hanging wall fast) appear to delineate the Alpine Fault at depth in most of our study region, dipping typically about 60 degrees SE, and some focal mechanisms show oblique slip. However, we are not able to identify earthquakes that are actually occurring on the Alpine Fault with certainty based only on our location results.

Alpine Grassland Soil Organic Carbon Stock and Its Uncertainty in the Three Rivers Source Region of the Tibetan Plateau

PubMed Central

Chang, Xiaofeng; Wang, Shiping; Cui, Shujuan; Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua; Wilkes, Andreas

2014-01-01

Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC) stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR), alpine grasslands account for more than 75% of the total area. However, the regional carbon (C) stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006–2008. We showed that the upper soil (0–30 cm depth) in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C) of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6–7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution. PMID:24819054

Separation of variables in Maxwell equations in Plebański-Demiański spacetime

NASA Astrophysics Data System (ADS)

Frolov, Valeri P.; Krtouš, Pavel; KubizÅák, David

2018-05-01

A new method for separating variables in the Maxwell equations in four- and higher-dimensional Kerr-(A)dS spacetimes proposed recently by Lunin is generalized to any off-shell metric that admits a principal Killing-Yano tensor. The key observation is that Lunin's ansatz for the vector potential can be formulated in a covariant form—in terms of the principal tensor. In particular, focusing on the four-dimensional case we demonstrate separability of Maxwell's equations in the Kerr-NUT-(A)dS and the Plebański-Demiański family of spacetimes. The new method of separation of variables is quite different from the standard approach based on the Newman-Penrose formalism.

Forest area and timber resources of the San Joaquin area, California.

Treesearch

Charles L. Bolsinger

1978-01-01

This report presents statistics on forest area and timber volume and a description of the recent and future timber situations in Alpine, Amador, Calaveras, Fresno, Kern, Kings, Madera, Mariposa, Merced, Mono, San Joaquin, Stanislaus, Tulare, and Tuolumne Counties, California.

Seismic signature of the Alpine indentation, evidence from the Eastern Alps

PubMed Central

Bianchi, I.; Bokelmann, G.

2014-01-01

The type of collision between the European and the Adriatic plates in the easternmost Alps is one of the most interesting questions regarding the Alpine evolution. Tectonic processes such as compression, escape and uplift are interconnected and shape this area. We can understand these ongoing processes better, if we look for signs of the deformation within the Earth's deep crust of the region. By collecting records from permanent and temporary seismic networks, we assemble a receiver function dataset, and analyze it with the aim of giving new insights on the structure of the lower crust and of the shallow portion of the upper mantle, which are inaccessible to direct observation. Imaging is accomplished by performing common conversion depth stacks along three profiles that crosscut the Eastern Alpine orogen, and allow isolating features consistently persistent in the area. The study shows a moderately flat Moho underlying a seismically anisotropic middle-lower crust from the Southern Alps to the Austroalpine nappes. The spatial progression of anisotropic axes reflects the orientation of the relative motion and of the stress field detected at the surface. These observations suggest that distributed deformation is due to the effect of the Alpine indentation. In the shallow upper mantle right below the Moho interface, a further anisotropic layer is recognized, extended from the Bohemian Massif to the Northern Calcareous Alps. PMID:26525181

Impacts of Projected Climate Warming and Wetting on Soil Microbial Communities in Alpine Grassland Ecosystems of the Tibetan Plateau.

PubMed

Zeng, Jun; Shen, Ju-Pei; Wang, Jun-Tao; Hu, Hang-Wei; Zhang, Cui-Jing; Bai, Ren; Zhang, Li-Mei; He, Ji-Zheng

2018-05-01

Climate change is projected to have impacts on precipitation and temperature regimes in drylands of high elevation regions, with especially large effects in the Qinghai-Tibetan Plateau. However, there was limited information about how the projected climate change will impact on the soil microbial community and their activity in the region. Here, we present results from a study conducted across 72 soil samples from 24 different sites along a temperature and precipitation gradient (substituted by aridity index ranging from 0.079 to 0.89) of the Plateau, to assess how changes in aridity affect the abundance, community composition, and diversity of bacteria, ammonia-oxidizers, and denitrifers (nirK/S and nosZ genes-containing communities) as well as nitrogen (N) turnover enzyme activities. We found V-shaped or inverted V-shaped relationships between the aridity index (AI) and soil microbial parameters (gene abundance, community structures, microbial diversity, and N turnover enzyme activities) with a threshold at AI = 0.27. The increasing or decreasing rates of the microbial parameters were higher in areas with AI < 0.27 (alpine steppes) than in mesic areas with 0.27 < AI < 0.89 (alpine meadow and swamp meadow). The results indicated that the projected warming and wetting have a strong impact on soil microbial communities in the alpine steppes.

Comparison modeling for alpine vegetation distribution in an arid area.

PubMed

Zhou, Jihua; Lai, Liming; Guan, Tianyu; Cai, Wetao; Gao, Nannan; Zhang, Xiaolong; Yang, Dawen; Cong, Zhentao; Zheng, Yuanrun

2016-07-01

Mapping and modeling vegetation distribution are fundamental topics in vegetation ecology. With the rise of powerful new statistical techniques and GIS tools, the development of predictive vegetation distribution models has increased rapidly. However, modeling alpine vegetation with high accuracy in arid areas is still a challenge because of the complexity and heterogeneity of the environment. Here, we used a set of 70 variables from ASTER GDEM, WorldClim, and Landsat-8 OLI (land surface albedo and spectral vegetation indices) data with decision tree (DT), maximum likelihood classification (MLC), and random forest (RF) models to discriminate the eight vegetation groups and 19 vegetation formations in the upper reaches of the Heihe River Basin in the Qilian Mountains, northwest China. The combination of variables clearly discriminated vegetation groups but failed to discriminate vegetation formations. Different variable combinations performed differently in each type of model, but the most consistently important parameter in alpine vegetation modeling was elevation. The best RF model was more accurate for vegetation modeling compared with the DT and MLC models for this alpine region, with an overall accuracy of 75 % and a kappa coefficient of 0.64 verified against field point data and an overall accuracy of 65 % and a kappa of 0.52 verified against vegetation map data. The accuracy of regional vegetation modeling differed depending on the variable combinations and models, resulting in different classifications for specific vegetation groups.

Seismic signature of the Alpine indentation, evidence from the Eastern Alps.

PubMed

Bianchi, I; Bokelmann, G

2014-12-01

The type of collision between the European and the Adriatic plates in the easternmost Alps is one of the most interesting questions regarding the Alpine evolution. Tectonic processes such as compression, escape and uplift are interconnected and shape this area. We can understand these ongoing processes better, if we look for signs of the deformation within the Earth's deep crust of the region. By collecting records from permanent and temporary seismic networks, we assemble a receiver function dataset, and analyze it with the aim of giving new insights on the structure of the lower crust and of the shallow portion of the upper mantle, which are inaccessible to direct observation. Imaging is accomplished by performing common conversion depth stacks along three profiles that crosscut the Eastern Alpine orogen, and allow isolating features consistently persistent in the area. The study shows a moderately flat Moho underlying a seismically anisotropic middle-lower crust from the Southern Alps to the Austroalpine nappes. The spatial progression of anisotropic axes reflects the orientation of the relative motion and of the stress field detected at the surface. These observations suggest that distributed deformation is due to the effect of the Alpine indentation. In the shallow upper mantle right below the Moho interface, a further anisotropic layer is recognized, extended from the Bohemian Massif to the Northern Calcareous Alps.

Groundwater Storage and Flow Pathways in a Rock Glacier Complex in the Canadian Rockies

NASA Astrophysics Data System (ADS)

Hayashi, M.; Mozil, A.; Harrington, J.; Bentley, L. R.

2015-12-01

Hydrological functions of alpine glaciers and their responses to the warming climate have received much attention by hydrologists working in alpine catchments around the world. As alpine glaciers retreat, they commonly leave debris-covered ice or ice-cored moraine behind, which can remain frozen in ground for many decades or centuries. In many alpine catchments, characteristic landforms indicating rock glaciers or their relicts are found in locations where glaciers do not exist under the current climate. These landscape features associated with mountain permafrost are ubiquitous in alpine catchments, but their hydrological functions have not received much attention. Do rock glaciers and other mountain-permafrost features contribute significantly to storage of snowmelt water and its delayed release to sustain baseflow in the critical alpine stream habitats? How are these storage functions responding to the climate warming? In order to answer these questions, we initiated a hydrological study of rock glaciers in an alpine catchment in the Canadian Rockies in 2014. We will present preliminary results of our study using geophysical imaging techniques, hydro-meteorological monitoring, and groundwater tracing using various environmental tracers. Key findings are: 1) substantial amount of permafrost exists in the rock glacier which is inactive (i.e. no active motion) under the present climate, 2) spatial distribution of permafrost is controlled by both meteorological and geological factors, 3) the rock glacier complex contributes 30-50 % of summer stream flow even though they occupy less than 5% of the catchment area, and 4) the low temperature (< 2 C) of groundwater discharging at the toe of rock glacier plays a significant role in regulating the temperature of stream, which hosts a population of trout species that is listed as "threatened" in the list of the status of endangered wildlife in Canada.

NFI-Ski interactions mediate transforming growth factor beta modulation of human papillomavirus type 16 early gene expression.

PubMed

Baldwin, Amy; Pirisi, Lucia; Creek, Kim E

2004-04-01

Human papillomaviruses (HPVs) are present in virtually all cervical cancers. An important step in the development of malignant disease, including cervical cancer, involves a loss of sensitivity to transforming growth factor beta (TGF-beta). HPV type 16 (HPV16) early gene expression, including that of the E6 and E7 oncoprotein genes, is under the control of the upstream regulatory region (URR), and E6 and E7 expression in HPV16-immortalized human epithelial cells is inhibited at the transcriptional level by TGF-beta. While the URR contains a myriad of transcription factor binding sites, including seven binding sites for nuclear factor I (NFI), the specific sequences within the URR or the transcription factors responsible for TGF-beta modulation of the URR remain unknown. To identify potential transcription factors and binding sites involved in TGF-beta modulation of the URR, we performed DNase I footprint analysis on the HPV16 URR using nuclear extracts from TGF-beta-sensitive HPV16-immortalized human keratinocytes (HKc/HPV16) treated with and without TGF-beta. Differentially protected regions were found to be located around NFI binding sites. Electrophoretic mobility shift assays, using the NFI binding sites as probes, showed decreased binding upon TGF-beta treatment. This decrease in binding was not due to reduced NFI protein or NFI mRNA levels. Mutational analysis of individual and multiple NFI binding sites in the URR defined their role in TGF-beta sensitivity of the promoter. Overexpression of the NFI family members in HKc/HPV16 decreased the ability of TGF-beta to inhibit the URR. Since the oncoprotein Ski has been shown to interact with and increase the transcriptional activity of NFI and since cellular Ski levels are decreased by TGF-beta treatment, we explored the possibility that Ski may provide a link between TGF-beta signaling and NFI activity. Anti-NFI antibodies coimmunoprecipitated endogenous Ski in nuclear extracts from HKc/HPV16, confirming that NFI and Ski interact in these cells. Ski levels dramatically decreased upon TGF-beta treatment of HKc/HPV16, and overexpression of Ski eliminated the ability of TGF-beta to inhibit the URR. Based on these studies, we propose that TGF-beta inhibition of HPV16 early gene expression is mediated by a decrease in Ski levels, which in turn dramatically reduces NFI activity.

On the potential asthenospheric linkage between Apenninic slab rollback and Alpine topographic uplift: insights from P wave tomography and seismic anisotropy analysis

NASA Astrophysics Data System (ADS)

Malusa', Marco Giovanni; Salimbeni, Simone; Zhao, Liang; Guillot, Stéphane; Pondrelli, Silvia; Margheriti, Lucia; Paul, Anne; Solarino, Stefano; Aubert, Coralie; Dumont, Thierry; Schwartz, Stéphane; Wang, Qingchen; Xu, Xiaobing; Zheng, Tianyu; Zhu, Rixiang

2017-04-01

The role of surface and deep-seated processes in controlling the topography of complex plate-boundary areas is a highly debated issue. In the Western Alps, which include the highest summits in Europe, factors controlling topographic uplift still remain poorly understood. In the absence of active convergence, recent works have suggested a potential linkage between slab breakoff and fast uplift, but this hypothesis is ruled out by the down-dip continuity of the Alpine slab documented by recent tomographic images of the upper mantle beneath the Alpine region (Zhao et al. 2016). In order to shed light on this issue, we use a densely spaced array of temporary broadband seismic stations and previously published observations to analyze the seismic anisotropy pattern along the transition zone between the Alps and the Apennines, within the framework of the upper mantle structure unveiled by P wave tomography. Our results show a continuous trend of anisotropy fast axes near-parallel to the western alpine arc, possibly due to an asthenospheric counterflow triggered by the eastward retreat of the Apenninic slab. This trend is located in correspondence of a low velocity anomaly in the European upper mantle, and beneath the Western Alps region characterized by the highest uplift rates, which may suggest a potential impact of mantle dynamics on Alpine topography. We propose that the progressive rollback of the Apenninic slab induced a suction effect and an asthenospheric counterflow at the rear of the unbroken Alpine slab and around its southern tip, as well as an asthenospheric upwelling, mirrored by low P wave velocities, which may have favored the topographic uplift of the Alpine belt from the Mt Blanc to the Ligurian coast. Zhao L. et al., 2016. Continuity of the Alpine slab unraveled by high-resolution P wave tomography. J. Geophys. Res., doi:10.1002/2016JB013310.

Eruptive history of Mammoth Mountain and its mafic periphery, California

USGS Publications Warehouse

Hildreth, Wes; Fierstein, Judy

2016-07-13

Many geographic names that appear in this report are informal despite having been in local use for decades. Most appear on maps distributed by the Town of Mammoth Lakes or the Mammoth Mountain Ski Area and can be found here on map figures 2–5, on several photo figures, and on the geologic map.

Regional trade market analysis: resort marketing approaches

Treesearch

David C. Bojanic; Rodney B. Warnick

1995-01-01

This paper examines the value of geographic segmentation for a regional ski resort in New England. Customers from different user groups were surveyed along with a list of inquiries and a purchased list, and grouped according to their area of origin. An ANOVA was performed to determine if there were differences in attitudes and trip behaviors between the segments. It...

Lift mechanics of downhill skiing and snowboarding.

PubMed

Wu, Qianhong; Igci, Yesim; Andreopoulos, Yiannis; Weinbaum, Sheldon

2006-06-01

This study is conducted to develop a simplified mathematical model to describe the lift mechanics of downhill skiing and snowboarding, where the lift contributions due to both the transiently trapped air and the compressed solid phase (snow crystals) are determined. To our knowledge, this is the first time that anyone has attempted to realistically estimate the relative contribution of the transiently trapped air to the total lift in skiing and snowboarding. The model uses Shimizu's empirical relation to predict the local variation in Darcy permeability due to the compression of the solid phase. The forces and moments on the skier or snowboarder are used to predict the angle of attack of the planing surface, the penetration depth at the leading edge, and the shift in the center of pressure for two typical snow types, fresh and wind-packed snow. We present numerical solutions for snowboarding and asymptotic analytic solutions for skiing for the case where there are no edging or turning maneuvers. The force and moment balance are then used to develop a theory for control and stability in response to changes in the center of mass as the individual shifts his/her weight. Our model predicts that for fine-grained, windpacked snow that when the velocity (U) of the snowboarder or skier is 20 m.s, approximately 50% of the total lift force is generated by the trapped air for snowboarding and 40% for skiing. For highly permeable fresh powder snow, the lift contribution from the pore air pressure drops substantially. This paper develops a new theoretical framework for analyzing the lift mechanics and stability of skis and snowboards that could have important applications in future ski and snowboard design.

The physiological and biomechanical contributions of poling to roller ski skating.

PubMed

Sandbakk, Øyvind; Ettema, Gertjan; Holmberg, Hans-Christer

2013-08-01

Poling is considered to make a significant contribution to cross-country skiing with the skating technique. To better understand this contribution, the current investigation compared roller ski skating on a treadmill with the so-called G3 skating technique with (G3-P) and without poling (G3-NP). Seven male elite skiers performed 5-min submaximal tests at 8, 12, and 15 km h(-1), as well as an incremental test to exhaustion with both techniques on a 5 % incline. Ventilatory variables were assessed by open-circuit indirect calorimetry and three-dimensional kinematics analyzed using the Qualisys Pro Reflex system. G3-P was associated with approximately 15 % higher peak velocity and 10 % higher peak oxygen uptake than G3-NP in the incremental test (both P < 0.01). All ventilatory variables, as well as heart rate and blood lactate concentration were lower with G3-P as compared to G3-NP at 12 and 15 km h(-1) (all P < 0.01). Gross efficiency (i.e., the ratio of work rate to metabolic rate) at 12 km h(-1) was higher in G3-P (14.9 %) than G3-NP (13.5 %) (P < 0.01). Moreover, with G3-P cycle time and length were both 30 % longer, with correspondingly reduced cycle rates (all P < 0.01). In addition, the ski gliding and swing phases were longer and the angle between the skis smaller with G3-P (both P < 0.01), whereas the push-off time was independent of technique and velocity. Taken together, these results indicate that poling makes an important contribution to propulsion and velocity during ski skating, specifically by enhancing peak oxygen uptake, skiing efficiency and associated biomechanical variables.

Effects of winter military training on energy balance, whole-body protein balance, muscle damage, soreness, and physical performance.

PubMed

Margolis, Lee M; Murphy, Nancy E; Martini, Svein; Spitz, Marissa G; Thrane, Ingjerd; McGraw, Susan M; Blatny, Janet-Martha; Castellani, John W; Rood, Jennifer C; Young, Andrew J; Montain, Scott J; Gundersen, Yngvar; Pasiakos, Stefan M

2014-12-01

Physiological consequences of winter military operations are not well described. This study examined Norwegian soldiers (n = 21 males) participating in a physically demanding winter training program to evaluate whether short-term military training alters energy and whole-body protein balance, muscle damage, soreness, and performance. Energy expenditure (D2(18)O) and intake were measured daily, and postabsorptive whole-body protein turnover ([(15)N]-glycine), muscle damage, soreness, and performance (vertical jump) were assessed at baseline, following a 4-day, military task training phase (MTT) and after a 3-day, 54-km ski march (SKI). Energy intake (kcal·day(-1)) increased (P < 0.01) from (mean ± SD (95% confidence interval)) 3098 ± 236 (2985, 3212) during MTT to 3461 ± 586 (3178, 3743) during SKI, while protein (g·kg(-1)·day(-1)) intake remained constant (MTT, 1.59 ± 0.33 (1.51, 1.66); and SKI, 1.71 ± 0.55 (1.58, 1.85)). Energy expenditure increased (P < 0.05) during SKI (6851 ± 562 (6580, 7122)) compared with MTT (5480 ± 389 (5293, 5668)) and exceeded energy intake. Protein flux, synthesis, and breakdown were all increased (P < 0.05) 24%, 18%, and 27%, respectively, during SKI compared with baseline and MTT. Whole-body protein balance was lower (P < 0.05) during SKI (-1.41 ± 1.11 (-1.98, -0.84) g·kg(-1)·10 h) than MTT and baseline. Muscle damage and soreness increased and performance decreased progressively (P < 0.05). The physiological consequences observed during short-term winter military training provide the basis for future studies to evaluate nutritional strategies that attenuate protein loss and sustain performance during severe energy deficits.

[Ski boots versus the knee joint. 2: What produces the forward leaning position of the ski boot?].

PubMed

Schaff, P; Hauser, W

1990-03-01

In contrast to the drop in the incidence of fracture of the lower leg that has been observed in recent years, the incidence of knee injuries has not decreased in skiing. There has even been a relative increase of severe knee lesions and isolated ACL ruptures, prompting us to conduct a comprehensive study of the causes of this phenomena. The goal of part 2 of the study was to comprehensively examine the forward movement in skiboots in the lab and on the slope. Studying nine beginners and eight experts, we found a 20% (sign. 0.05) lower forward-lean capability for the beginner group in the same boot. A randomized study with crossover design conducted on the slope, where we equipped 16 skiers with either soft or stiff boots for the duration of five ski days, revealed the learning behaviour and forward position on the slope depending on the boot. The pupils became definitely less adept at learning if they were required to wear stiff skiboots and showed a sign, lower forward flex angle. A skiiing style in backward lean position was adopted and supported by the fixed backward spoiler. Therefore another study was necessary and will follow (part 3) to examine the effect of a stiff backward spoiler and skiing in a backward lean position. In consideration of the facts known up to now, it is concluded that to improve safety in skiing recommendations must be given as to which boot to choose, according to the skiing level. In addition, the setting of safety bindings must consider the type of skiboot used.

Mechanisms of action of acetaldehyde in the up-regulation of the human α2(I) collagen gene in hepatic stellate cells: key roles of Ski, SMAD3, SMAD4, and SMAD7.

PubMed

Reyes-Gordillo, Karina; Shah, Ruchi; Arellanes-Robledo, Jaime; Hernández-Nazara, Zamira; Rincón-Sánchez, Ana Rosa; Inagaki, Yutaka; Rojkind, Marcos; Lakshman, M Raj

2014-05-01

Alcohol-induced liver fibrosis and eventually cirrhosis is a leading cause of death. Acetaldehyde, the first metabolite of ethanol, up-regulates expression of the human α2(I) collagen gene (COL1A2). Early acetaldehyde-mediated effects involve phosphorylation and nuclear translocation of SMAD3/4-containing complexes that bind to COL1A2 promoter to induce fibrogenesis. We used human and mouse hepatic stellate cells to elucidate the mechanisms whereby acetaldehyde up-regulates COL1A2 by modulating the role of Ski and the expression of SMADs 3, 4, and 7. Acetaldehyde induced up-regulation of COL1A2 by 3.5-fold, with concomitant increases in the mRNA (threefold) and protein (4.2- and 3.5-fold) levels of SMAD3 and SMAD4, respectively. It also caused a 60% decrease in SMAD7 expression. Ski, a member of the Ski/Sno oncogene family, is colocalized in the nucleus with SMAD4. Acetaldehyde induces translocation of Ski and SMAD4 to the cytoplasm, where Ski undergoes proteasomal degradation, as confirmed by the ability of the proteasomal inhibitor lactacystin to blunt up-regulation of acetaldehyde-dependent COL1A2, but not of the nonspecific fibronectin gene (FN1). We conclude that acetaldehyde up-regulates COL1A2 by enhancing expression of the transactivators SMAD3 and SMAD4 while inhibiting the repressor SMAD7, along with promoting Ski translocation from the nucleus to cytoplasm. We speculate that drugs that prevent proteasomal degradation of repressors targeting COL1A2 may have antifibrogenic properties. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Winter streamflow analysis in frozen, alpine catchments to quantify groundwater contribution and properties

NASA Astrophysics Data System (ADS)

Stoelzle, Michael; Weiler, Markus

2016-04-01

Alpine catchments are often considered as quickly responding systems where streamflow contributions from subsurface storages (groundwater) are mostly negligible due to the steep topography, low permeable bedrock and the absence of well-developed soils. Many studies in high altitude catchments have hence focused on water stored in snowpack and glaciers or on rainfall-runoff processes as the dominant streamflow contributions. Interestingly less effort has been devoted to winter streamflow analysis when melt- or rainfall-driven contributions are switched off due to the frozen state of the catchment. Considering projected changes in the alpine cryosphere (e.g. snow, glacier, permafrost) quantification of groundwater storage and contribution to streamflow is crucial to assess the social and ecological implications for downstream areas (e.g. water temperature, drought propagation). In this study we hypothesize that groundwater is the main streamflow contribution during winter and thus being responsible for the perennial regime of many alpine catchments. The hypothesis is investigated with well-known methods based on recession and breakpoint analysis of the streamflow regimes and temperature data to determine frozen periods. Analyzing nine catchments in Switzerland with mean elevation between 1000 and 2400 m asl, we found that above a mean elevation of 1800 m asl winter recessions are sufficient long and persistent enough to quantify groundwater contribution to streamflow and to characterize the properties of subsurface storage. The results show that groundwater in alpine catchment is the dominant streamflow contribution for nearly half a year and accountable for several hundred millimeter of annual streamflow. In sub-alpine catchments, driven by a mix of snowmelt and rainfall, a clear quantification of groundwater contributions is rather challenging due to discontinuous frozen periods in winter. We found that the inter-annual variability of different streamflow contributions is helpful to assess the water sustainability of alpine catchments functioning as water towers for downstream water basins. We outline how well-known hydrograph and recession analyses in alpine catchments can help to explore the role of catchment storage and to advance our understanding of (ground-)water management in alpine environments.

[Doctor's degree thesis of Tomasz Adolf Wołkowiński "Carditidis rheumaticae historia"].

PubMed

Stembrowicz, W

2001-01-01

In 1817 on the University of Vilnius Faculty of Medicine, T. A. Wołkowiński, a student of the eminent clinician Józef Frank, defended his doctor's degree thesis about a direct relation between rheumatic disease and cardiomegaly. It was probably the first paper in Poland describing with details the rheumatic heart disease. Unfortunately we don't know much about T. A. Wołkowiński's life.

Recognition of hyper-extended rifted margin remnants in the internal zone of the Alpine belt: A tribute to Marco Beltrando

NASA Astrophysics Data System (ADS)

Mohn, Geoffroy; Manatschal, Gianreto

2016-04-01

Marco Beltrando was part of the young generation of Alpine geologists who challenged the interpretation of the Western Alps by combining a classical field approach and modern techniques (e.g. 40Ar/39Ar and (U-Th)/He thermochronology). His work provides the foundation to re-interpret some of the classical sections through the Alpine belt and may impact the way of thinking about the nature and structure of internal parts of collisional orogens. This contribution will present the main outcomes of the work of Marco Beltrando and their implications for the understanding of Alpine type orogens. Since his PhD, Marco Beltrando focused most of his work on the study of the internal parts of the Western Alps. He investigated in great details the complex, multiphase structural and metamorphic evolution of the Penninic units in the Western Alps. He concluded that these units went through several cycles of shortening and extension during the Alpine orogeny, with major implications for the Alps but also other orogenic belts. After his PhD, he focused his research on the pre-orogenic evolution of the Alpine belt. He first worked on the Petit St. Bernard area, where he identified relics of the former hyper-extended Tethyan rifted margin. Thanks to his work and his amazing knowledge of the Western Alps, he understood the potential importance of rift-inheritance in controlling the architecture and evolution of the Alpine belt. In parallel to the study of the orogenic evolution, he developed a new methodology to recognize rift-related lithostratigraphic units in highly deformed and metamorphosed parts of the Alps. His innovative work allowed a re-assessment of several areas in the Western Alps and demonstrates the importance of rift inheritance. Recently, he started a new research project on the evolution of the Southern Alps highlighting the importance of heating and cooling cycles resulting from complex successions of rifting events. In spite of his young age, Marco Beltrando was at the forefront of new techniques, ideas and concepts that ultimately will improve our understanding of mountain belts and rift systems. Eventually more than anything, his motivation and enthusiasm were a constant source of inspiration.

SKI2 mediates degradation of RISC 5′-cleavage fragments and prevents secondary siRNA production from miRNA targets in Arabidopsis

PubMed Central

Branscheid, Anja; Marchais, Antonin; Schott, Gregory; Lange, Heike; Gagliardi, Dominique; Andersen, Stig Uggerhøj; Voinnet, Olivier; Brodersen, Peter

2015-01-01

Small regulatory RNAs are fundamental in eukaryotic and prokaryotic gene regulation. In plants, an important element of post-transcriptional control is effected by 20–24 nt microRNAs (miRNAs) and short interfering RNAs (siRNAs) bound to the ARGONAUTE1 (AGO1) protein in an RNA induced silencing complex (RISC). AGO1 may cleave target mRNAs with small RNA complementarity, but the fate of the resulting cleavage fragments remains incompletely understood. Here, we show that SKI2, SKI3 and SKI8, subunits of a cytoplasmic cofactor of the RNA exosome, are required for degradation of RISC 5′, but not 3′-cleavage fragments in Arabidopsis. In the absence of SKI2 activity, many miRNA targets produce siRNAs via the RNA-dependent RNA polymerase 6 (RDR6) pathway. These siRNAs are low-abundant, and map close to the cleavage site. In most cases, siRNAs were produced 5′ to the cleavage site, but several examples of 3′-spreading were also identified. These observations suggest that siRNAs do not simply derive from RDR6 action on stable 5′-cleavage fragments and hence that SKI2 has a direct role in limiting secondary siRNA production in addition to its function in mediating degradation of 5′-cleavage fragments. PMID:26464441

The ERK/CREB pathway is involved in the c-Ski expression induced by low TGF-β1 concentrations during primary fibroblast proliferation.

PubMed

Li, Ping; Liu, Ping; Peng, Yan; Zhang, Zhuo-Hang; Li, Xiao-Ming; Xiong, Ren-Ping; Chen, Xing; Zhao, Yan; Ning, Ya-Lei; Yang, Nan; Zhang, Bo; Zhou, Yuan-Guo

2018-06-27

Increasing evidence has suggested that bidirectional regulation of cell proliferation is one important effect of TGF-β1 in wound healing. Increased c-Ski expression plays a role in promoting fibroblast proliferation at low TGF-β1 concentrations, but the mechanism by which low TGF-β1 concentrations regulate c-Ski levels remains unclear. In this study, the proliferation of rat primary fibroblasts was assessed with an ELISA BrdU kit. The mRNA and protein expression and phosphorylation levels of corresponding factors were measured by RT-qPCR, immunohistochemistry or Western blotting. We first found that low TGF-β1 concentrations not only promoted c-Ski mRNA and protein expression in rat primary fibroblasts but also increased the phosphorylation levels of Extracellular Signal-Regulated Kinases (ERK) and cAMP response element binding (CREB) protein. An ERK kinase (mitogen-activated protein kinase kinase, MEK) inhibitor significantly inhibited ERK1/2 phosphorylation levels, markedly reducing c-Ski expression and CREB phosphorylation levels and abrogating the growth-promoting effect of low TGF-β1 concentrations. At the same time, Smad2/3 phosphorylation levels were not significantly changed. Taken together, these results suggest that the increased cell proliferation induced by low TGF-β1 concentrations mediates c-Ski expression potentially through the ERK/CREB pathway rather than through the classic TGF-β1/Smad pathway.

Chromosomal instability in mouse embryonic fibroblasts null for the transcriptional co-repressor Ski.

PubMed

Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J

2012-01-01

Ski is a transcriptional regulator that has been considered an oncoprotein given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski-/- mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chromatin/chromosome bridges as the major cause of micronuclei (MN) formation and the subsequent aneuploidy. Although these cells arrested in mitosis after treatment with spindle disrupting drugs and exhibited a delayed metaphase/anaphase transition, spindle assembly checkpoint (SAC) was not sufficient to prevent chromosome missegregation, consistent with a weakened SAC. Our in vivo analysis also showed dynamic metaphase plate rearrangements with switches in polarity in cells arrested in metaphase. Importantly, after ectopic expression of Ski the cells that displayed this metaphase arrest died directly during metaphase or after aberrant cell division, relating SAC activation and mitotic cell death. This increased susceptibility to undergo mitosis-associated cell death reduced the number of MN-containing cells. The presented data support a new role for Ski in the mitotic process and in maintenance of genetic stability, providing insights into the mechanism of tumor suppression mediated by this protein. Copyright © 2011 Wiley Periodicals, Inc.

CryoEM structure of yeast cytoplasmic exosome complex.

PubMed

Liu, Jun-Jie; Niu, Chu-Ya; Wu, Yao; Tan, Dan; Wang, Yang; Ye, Ming-Da; Liu, Yang; Zhao, Wenwei; Zhou, Ke; Liu, Quan-Sheng; Dai, Junbiao; Yang, Xuerui; Dong, Meng-Qiu; Huang, Niu; Wang, Hong-Wei

2016-07-01

The eukaryotic multi-subunit RNA exosome complex plays crucial roles in 3'-to-5' RNA processing and decay. Rrp6 and Ski7 are the major cofactors for the nuclear and cytoplasmic exosomes, respectively. In the cytoplasm, Ski7 helps the exosome to target mRNAs for degradation and turnover via a through-core pathway. However, the interaction between Ski7 and the exosome complex has remained unclear. The transaction of RNA substrates within the exosome is also elusive. In this work, we used single-particle cryo-electron microscopy to solve the structures of the Ski7-exosome complex in RNA-free and RNA-bound forms at resolutions of 4.2 Å and 5.8 Å, respectively. These structures reveal that the N-terminal domain of Ski7 adopts a structural arrangement and interacts with the exosome in a similar fashion to the C-terminal domain of nuclear Rrp6. Further structural analysis of exosomes with RNA substrates harboring 3' overhangs of different length suggests a switch mechanism of RNA-induced exosome activation in the through-core pathway of RNA processing.

Subarctic, alpine nesting by Bairds Sandpipers Calidris bairdii

USGS Publications Warehouse

Gill, Robert E.; Tomkovich, Pavel S.

2004-01-01

Baird's Sandpipers Calidris bairdii were found nesting in alpine habitat in southwestern Alaska (60°48'N, 154°00'W), almost 250 km from the nearest known breeding site, and studied over three consecutive seasons, 1997-1999. The first birds arrived during the second week of May each spring with peak numbers recorded the third week of May. Most nests and newly hatched broods were found on sparsely vegetated dwarf shrub-lichen mat tundra on level or gently sloping areas throughout the alpine zone between 980 and 1400 m above sea level. Most eggs hatched during the third week of June and independent young were noted during the second and third weeks of July. Both parents initially tended broods, but only the male remained after chicks were about four days of age. During early brood-rearing, adults began to move chicks, often to higher elevations and over distances of several hundred metres. Throughout the area the density of nesting birds was about 0.2 pairs/km 2 with up to 0.9 pairs/km 2 found on southerly exposures of the north study slope. A summary of available information revealed the global nesting distribution of bairdii to be strongly associated with disturbed landscapes, especially montane areas affected by glaciation, suggesting the breeding range is likely to be much more extensive than currently known, especially in areas of Alaska, the Yukon, and possibly Chukotka.

[A large-scale accident in Alpine terrain].

PubMed

Wildner, M; Paal, P

2015-02-01

Due to the geographical conditions, large-scale accidents amounting to mass casualty incidents (MCI) in Alpine terrain regularly present rescue teams with huge challenges. Using an example incident, specific conditions and typical problems associated with such a situation are presented. The first rescue team members to arrive have the elementary tasks of qualified triage and communication to the control room, which is required to dispatch the necessary additional support. Only with a clear "concept", to which all have to adhere, can the subsequent chaos phase be limited. In this respect, a time factor confounded by adverse weather conditions or darkness represents enormous pressure. Additional hazards are frostbite and hypothermia. If priorities can be established in terms of urgency, then treatment and procedure algorithms have proven successful. For evacuation of causalities, a helicopter should be strived for. Due to the low density of hospitals in Alpine regions, it is often necessary to distribute the patients over a wide area. Rescue operations in Alpine terrain have to be performed according to the particular conditions and require rescue teams to have specific knowledge and expertise. The possibility of a large-scale accident should be considered when planning events. With respect to optimization of rescue measures, regular training and exercises are rational, as is the analysis of previous large-scale Alpine accidents.

Smad3 allostery links TGF-β receptor kinase activation to transcriptional control

PubMed Central

Qin, Bin Y.; Lam, Suvana S.; Correia, John J.; Lin, Kai

2002-01-01

Smad3 transduces the signals of TGF-βs, coupling transmembrane receptor kinase activation to transcriptional control. The membrane-associated molecule SARA (Smad Anchor for Receptor Activation) recruits Smad3 for phosphorylation by the receptor kinase. Upon phosphorylation, Smad3 dissociates from SARA and enters the nucleus, in which its transcriptional activity can be repressed by Ski. Here, we show that SARA and Ski recognize specifically the monomeric and trimeric forms of Smad3, respectively. Thus, trimerization of Smad3, induced by phosphorylation, simultaneously activates the TGF-β signal by driving Smad3 dissociation from SARA and sets up the negative feedback mechanism by Ski. Structural models of the Smad3/SARA/receptor kinase complex and Smad3/Ski complex provide insights into the molecular basis of regulation. PMID:12154125

The AlpArray Seismic Network: status and operation

NASA Astrophysics Data System (ADS)

Hetényi, György; Molinari, Irene; Clinton, John; Kissling, Edi

2017-04-01

The AlpArray initiative (http://www.alparray.ethz.ch) is a large-scale European collaboration to study the entire Alpine orogen at high resolution and in 3D with a large variety of geoscientific methods. The core element of the initiative is an extensive and dense broadband seismological network, the AlpArray Seismic Network (AASN). Over 300 temporary stations complement the permanent seismological stations to ensure homogeneous coverage of the greater Alpine area. The AASN has officially started operation in January 2016 and is now complete on land. It is operated in a joint effort by a number of institutions from Austria, Bosnia-Herzegovina, Croatia, Czech Republic, France, Germany, Hungary, Italy, Slovakia and Switzerland. In the Ligurian Sea, a 32-station OBS campaign is planned from June 2017 until March 2018. This will complete the coverage of the greater Alpine area at an unprecedented resolution. In this poster we present the actual status of the deployment, the effort undertaken by the contributing groups, station performance, best practices, data management as well as often encountered challenges, and provide a meeting and discussion point during the conference.

Winter Tourism and mountain wetland management and restoration

NASA Astrophysics Data System (ADS)

Gaucherand, S.; Mauz, I.

2012-04-01

The degradation and loss of wetlands is more rapid than that of other ecosystems (MEA 2005). In mountains area, wetlands are small and scattered and particularly sensitive to global change. The development of ski resorts can lead to the destruction or the deterioration of mountain wetlands because of hydrologic interferences, fill in, soil compression and erosion, etc. Since 2008, we have studied a high altitude wetland complex in the ski resort of Val Thorens. The aim of our study was to identify the impacts of mountain tourism development (winter and summer tourism) on wetland functioning and to produce an action plan designed to protect, rehabilitate and value the wetlands. We chose an approach based on multi-stakeholder participatory process at every stage, from information gathering to technical choices and monitoring. In this presentation, we show how such an approach can efficiently improve the consideration of wetlands in the development of a ski resort, but also the bottlenecks that need to be overcome. We will also discuss some of the ecological engineering techniques used to rehabilitate or restore high altitude degraded wetlands. Finally, this work has contributed to the creation in 2012 of a mountain wetland observatory coordinated by the conservatory of Haute-Savoie. The objective of this observatory is to estimate ecosystem services furnished by mountain wetlands and to find restoration strategies adapted to the local socio-economical context (mountain agriculture and mountain tourism).

Identification of groundwater nitrate sources in pre-alpine catchments: a multi-tracer approach

NASA Astrophysics Data System (ADS)

Stoewer, Myriam; Stumpp, Christine

2014-05-01

Porous aquifers in pre-alpine areas are often used as drinking water resources due to their good water quality status and water yield. Maintaining these resources requires knowledge about possible sources of pollutants and a sustainable management practice in groundwater catchment areas. Of particular interest in agricultural areas, like in pre-alpine regions, is limiting nitrate input as main groundwater pollutant. Therefore, the objective of the presented study is i) to identify main nitrate sources in a pre-alpine groundwater catchment with current low nitrate concentration using stable isotopes of nitrate (d18O and d15N) and ii) to investigate seasonal dynamics of nitrogen compounds. The groundwater catchment areas of four porous aquifers are located in Southern Germany. Most of the land use is organic grassland farming as well as forestry and residential area. Thus, potential sources of nitrate mainly are mineral fertilizer, manure/slurry, leaking sewage system and atmospheric deposition of nitrogen compounds. Monthly freshwater samples (precipitation, river water and groundwater) are analysed for stable isotope of water (d2H, d18O), the concentration of major anions and cations, electrical conductivity, water temperature, pH and oxygen. In addition, isotopic analysis of d18O-NO3- and d15N-NO3- for selected samples is carried out using the denitrifier method. In general, all groundwater samples were oxic (10.0±2.6mg/L) and nitrate concentrations were low (0.2 - 14.6mg/L). The observed nitrate isotope values in the observation area compared to values from local precipitation, sewage, manure and mineral fertilizer as well as to data from literature shows that the nitrate in freshwater samples is of microbial origin. Nitrate derived from ammonium in fertilizers and precipitation as well as from soil nitrogen. It is suggested that a major potential threat to the groundwater quality is ammonia and ammonium at a constant level mainly from agriculture activities as well as continuously release of nitrogen stored in agricultural soils due to mineralization processes. In all groundwater and river water samples a seasonal variation of nitrate sources and concentration is absent but nitrate in precipitation shows a clear seasonal variation with peaks in spring and fall according to agricultural activity. This points to dilution effects of high nitrate inputs due to the large groundwater volume and mean residence time and highlights the function of soil as initial sink for nitrogen compounds delivered by fertilizer. Even though nitrate contamination was low in the study area, the results emphasize the importance of reducing additional nitrate sources in pre-alpine oxic aquifers. This will maintain the good water quality status of the aquifers and enable its use for drinking water supply.

36 CFR 3.12 - May I use a vessel to tow a person for water skiing or other similar activities?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false May I use a vessel to tow a person for water skiing or other similar activities? 3.12 Section 3.12 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.12 May I use a vessel to tow a person for water skiing o...

36 CFR 3.12 - May I use a vessel to tow a person for water skiing or other similar activities?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false May I use a vessel to tow a person for water skiing or other similar activities? 3.12 Section 3.12 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.12 May I use a vessel to tow a person for water skiing o...

The Glacier National Park GLORIA Project: A new US Target Region for Alpine Plant Monitoring Installed in the Northern Rocky Mountains, Montana

NASA Astrophysics Data System (ADS)

Holzer, K.; Fagre, D.

2004-12-01

The Global Observation Research Initiative in Alpine Environments (GLORIA) is an international research network whose purpose is to assess climate change impacts on vegetation in alpine environments worldwide. A standard protocol was developed by the international office in Vienna, Austria, and has specific site requirements and techniques that allow sites to be compared worldwide. This protocol requires four summits to be selected within a target region, covering zonal differences of subalpine to nival, and on each of these summits intensive vegetation plots are set up and monitored on a five year interval. Only three target regions in North America have been completed to date, one in Glacier National Park, Montana, and the other two in the Sierra Nevada and White Mountains, California. The four GLORIA summit plots in Glacier National Park were completed over the summers of 2003 and 2004. Because the Continental Divide bisects Glacier National Park (north to south), we chose summits only East of the divide to stay within a similar climatic pattern. Establishing sites was difficult due to the steep and rocky glaciated terrain and the remoteness of suitable sites that required multi-day approaches. Our highest summit (Seward Mtn. 2717 m) is the northernmost and our lowest summit (Dancing Lady Mtn. 2245 m) is southernmost. Treeline is strongly influenced by terrain and is significantly more variable than in the central Rocky Mountains. This also was true of zonal differences of alpine vegetation. Subalpine and even grassland species were found on the same summits as upper alpine species and areas considered subnival. While different zonal areas often occurred on one summit, they were highly influenced by the aspect and slope of that summit area. Between 51 and 82 vascular plants were documented on each summit. There was a high degree of variability in species diversity and percent cover on each summit that was correlated to directional exposure. The summit morphology caused loose vegetative associations, or micro-communities, that varied with exposure, slope angle, and substrate character. Species that exhibited dominance within the target region were Smelowskia calycina var. americana, Polemonium viscosum, Achillea millefolium, Erigeron compositus var. glabratus, and Potentilla fruticosa L. These species reflected the same variability in percent cover on the four sides of the summit areas as did the vegetation as a whole, but were present on all sides.

Spatial Analysis of the Effects of the Anomalous Winter of 2014/15 on 157 Ski Resorts Located in Western North America

NASA Astrophysics Data System (ADS)

Bahbahani, K. M.; Pidwirny, M. J.

2017-12-01

The winter of 2014/2015 was one of the warmest in recent history for many locations in western North America. The cause of this climate irregularity was the development of extremely warm ocean surface waters (The Blob) over much of the eastern North Pacific Ocean. During this winter season, many ski resorts in western Canada and the United States either did not open or were forced to close their ski season early. Here, we examine climate data from 157 ski resorts to develop a picture of where the effected locations were in western North America. Using the climate database software ClimateBC and ClimateNA, high quality downscaled historical data was generated for the winter season (December, January, and February) for the variables mean temperature, snowfall, and rainfall. Values for winter of 2014/15 were statistically compared to the 30-year normal period from 1981-2010. Z-scores were calculated for 2014/15 relative to the selected 30-year normal period. These Z-score values were then mapped using ArcGIS. From the mean winter temperature map, it is apparent that abnormally warm temperatures influenced many ski resorts in California, Nevada, western Oregon, Washington, Arizona, Utah, southern Idaho, and parts of southern British Columbia. The winter snowfall map shows anomalous below normal conditions only at two resorts in south-central British Columbia and a single above normal situation at one site in central Colorado. The winter rainfall map displays that many ski resorts in New Mexico, Arizona, southern Utah, Colorado, Wyoming, Montana, Idaho, western Washington, and southwestern British Columbia experienced exceptional above normal winter season rainfalls. It is highly likely that the next Blob will be forecasted many months in advance of its occurrence. The results of this study have identified which ski resorts could be climatically influenced by such an event. This information may help reduce potential financial losses to ski resorts and their associated stakeholders when the next Blob shows up.

Fluorine-labeled Dasatinib Nanoformulations as Targeted Molecular Imaging Probes in a PDGFB-driven Murine Glioblastoma Model12

PubMed Central

Benezra, Miriam; Hambardzumyan, Dolores; Penate-Medina, Oula; Veach, Darren R; Pillarsetty, Nagavarakishore; Smith-Jones, Peter; Phillips, Evan; Ozawa, Tatsuya; Zanzonico, Pat B; Longo, Valerie; Holland, Eric C; Larson, Steven M; Bradbury, Michelle S

2012-01-01

Dasatinib, a new-generation Src and platelet-derived growth factor receptor (PDGFR) inhibitor, is currently under evaluation in high-grade glioma clinical trials. To achieve optimum physicochemical and/or biologic properties, alternative drug delivery vehicles may be needed. We used a novel fluorinated dasatinib derivative (F-SKI249380), in combination with nanocarrier vehicles and metabolic imaging tools (microPET) to evaluate drug delivery and uptake in a platelet-derived growth factor B (PDGFB)-driven genetically engineered mouse model (GEMM) of high-grade glioma. We assessed dasatinib survival benefit on the basis of measured tumor volumes. Using brain tumor cells derived from PDGFB-driven gliomas, dose-dependent uptake and time-dependent inhibitory effects of F-SKI249380 on biologic activity were investigated and compared with the parent drug. PDGFR receptor status and tumor-specific targeting were non-invasively evaluated in vivo using 18F-SKI249380 and 18F-SKI249380-containing micellar and liposomal nanoformulations. A statistically significant survival benefit was found using dasatinib (95 mg/kg) versus saline vehicle (P < .001) in tumor volume-matched GEMM pairs. Competitive binding and treatment assays revealed comparable biologic properties for F-SKI249380 and the parent drug. In vivo, Significantly higher tumor uptake was observed for 18F-SKI249380-containing micelle formulations [4.9 percentage of the injected dose per gram tissue (%ID/g); P = .002] compared to control values (1.6%ID/g). Saturation studies using excess cold dasatinib showed marked reduction of tumor uptake values to levels in normal brain (1.5%ID/g), consistent with in vivo binding specificity. Using 18F-SKI249380-containing micelles as radiotracers to estimate therapeutic dosing requirements, we calculated intratumoral drug concentrations (24–60 nM) that were comparable to in vitro 50% inhibitory concentration values. 18F-SKI249380 is a PDGFR-selective tracer, which demonstrates improved delivery to PDGFB-driven high-grade gliomas and facilitates treatment planning when coupled with nanoformulations and quantitative PET imaging approaches. PMID:23308046

Evaluation of SNODAS snow depth and snow water equivalent estimates for the Colorado Rocky Mountains, USA

USGS Publications Warehouse

Clow, David W.; Nanus, Leora; Verdin, Kristine L.; Schmidt, Jeffrey

2012-01-01

The National Weather Service's Snow Data Assimilation (SNODAS) program provides daily, gridded estimates of snow depth, snow water equivalent (SWE), and related snow parameters at a 1-km2 resolution for the conterminous USA. In this study, SNODAS snow depth and SWE estimates were compared with independent, ground-based snow survey data in the Colorado Rocky Mountains to assess SNODAS accuracy at the 1-km2 scale. Accuracy also was evaluated at the basin scale by comparing SNODAS model output to snowmelt runoff in 31 headwater basins with US Geological Survey stream gauges. Results from the snow surveys indicated that SNODAS performed well in forested areas, explaining 72% of the variance in snow depths and 77% of the variance in SWE. However, SNODAS showed poor agreement with measurements in alpine areas, explaining 16% of the variance in snow depth and 30% of the variance in SWE. At the basin scale, snowmelt runoff was moderately correlated (R2 = 0.52) with SNODAS model estimates. A simple method for adjusting SNODAS SWE estimates in alpine areas was developed that uses relations between prevailing wind direction, terrain, and vegetation to account for wind redistribution of snow in alpine terrain. The adjustments substantially improved agreement between measurements and SNODAS estimates, with the R2 of measured SWE values against SNODAS SWE estimates increasing from 0.42 to 0.63 and the root mean square error decreasing from 12 to 6 cm. Results from this study indicate that SNODAS can provide reliable data for input to moderate-scale to large-scale hydrologic models, which are essential for creating accurate runoff forecasts. Refinement of SNODAS SWE estimates for alpine areas to account for wind redistribution of snow could further improve model performance. Published 2011. This article is a US Government work and is in the public domain in the USA.

Alpine forest-tundra ecotone response to temperature change,Sayan Mountains, Siberia

NASA Technical Reports Server (NTRS)

Ranson, K Jon; Kharuk, Vyetcheslav I.

2007-01-01

Models of climate change predict shifts of vegetation zones. Tree response to climate trends is most likely observable in the forest-tundra ecotone, where temperature mainly limits tree growth. There is evidence of vegetation change on the northern treeline However, observations on alpine tree line response are controversial. In this NEESPI related study we show that during the past three decades in the forest-tundra ecotone of the Sayan Mountains, Siberia, there was an increase in forest stand crown closure, regeneration propagation into the alpine tundra, and transformation of prostrate Siberian pine and fir into arboreal forms. We found that these changes occurred since the mid 1980s, and strongly correlates with positive temperature (and to a lesser extent, precipitation) trends. Improving climate for forest growth( i.e., warmer temperatures and increased precipitation) provides competitive advantages to Siberian pine in the alpine forest-tundra ecotone, as well as in areas typically dominated by larch, where it has been found to be forming a secondary canopy layer. Substitution of deciduous conifer, larch, for evergreen conifers, decreases albedo and provides positive feedback for temperature increase.

Metagenomic analysis of the soil microbial N-cycling community in response to increased N deposition in the alpine PNW

NASA Astrophysics Data System (ADS)

Simpson, A.; Zabowski, D.

2016-12-01

The effects of nitrogen (N) deposition, caused by increasing agricultural activity and increased fossil fuel usage in populated areas, is of great concern to managers of formerly pristine, N-limited environments such as the alpine. Increasingly available mineral N can cause changes in the soil microbial community, including downshifting naturally N-fixing microbial populations, and increasing nitrification (and soil acidification) with concomitant increases in nitrous oxide release. As part of a larger study to determine critical N loads for PNW alpine ecosystems, we used inorganic N fertilization to mimic increasing levels of N deposition at alpine sites at Mount Rainier, North Cascades, and Olympic National Parks. After 3 years of N application, we isolated DNA from soil samples taken from the rooting zones of two different species categories - lupine spp. and heather (evergreen shrub) spp. Amplicon-based libraries for genes for nitrogenase and ammonia monooxygenase were sequenced for each level of fertilization. We will present changes in diversity and size of the N-fixing and nitrifying microbial communities by increasing N application, site, and plant community.

Grizzly bear use of army cutworm moths in the Yellowstone Ecosystem

USGS Publications Warehouse

French, Steven P.; French, Marilynn G.; Knight, Richard R.

1994-01-01

The ecology of alpine aggregations of army cutworm moths (Euxoa auxiliaris) and the feeding behavior of grizzly bears (Ursus arctos horribilis) at these areas were studied in the Yellowstone ecosystem from 1988 to 1991. Army cutworm moths migrate to mountain regions each summer to feed at night on the nectar of alpine and subalpine flowers, and during the day they seek shelter under various rock formations. Grizzly bears were observed feeding almost exclusively on moths up to 3 months each summer at the 10 moth-aggregation areas we identified. Fifty-one different grizzly bears were observed feeding at 4 of these areas during a single day in August 1991. Army cutworm moths are a preferred source of nutrition for many grizzly bears in the Yellowstone ecosystem and represent a high quality food that is available during hyperphagia.

Two short segments of Smad3 are important for specific interaction of Smad3 with c-Ski and SnoN.

PubMed

Mizuide, Masafumi; Hara, Takane; Furuya, Toshio; Takeda, Masafumi; Kusanagi, Kiyoshi; Inada, Yuri; Mori, Masatomo; Imamura, Takeshi; Miyazawa, Keiji; Miyazono, Kohei

2003-01-03

c-Ski and SnoN are transcriptional co-repressors that inhibit transforming growth factor-beta signaling through interaction with Smad proteins. Among receptor-regulated Smads, c-Ski and SnoN bind more strongly to Smad2 and Smad3 than to Smad1. Here, we show that c-Ski and SnoN bind to the "SE" sequence in the C-terminal MH2 domain of Smad3, which is exposed on the N-terminal upper side of the toroidal structure of the MH2 oligomer. The "QPSMT" sequence, located in the vicinity of SE, supports the interaction with c-Ski and SnoN. Sequences similar to SE and QPSMT are found in Smad2, but not in Smad1. The N-terminal MH1 domain and linker region of Smad3 protrude from the N-terminal upper side of the MH2 oligomer toroid. Smurf2 induces ubiquitin-dependent degradation of SnoN, since it appears to be located close to SnoN through binding to the linker region of Smad2. In contrast, transcription factors Mixer and FoxH3 (FAST1) bind to the bottom side of the Smad3 MH2 toroid; therefore, c-Ski does not affect the interaction of Smads with these transcription factors. Our findings thus demonstrate the stoichiometry of how multiple molecules can associate with the Smad oligomers and how the Smad-interacting proteins functionally interact with each other.

SKI2 mediates degradation of RISC 5'-cleavage fragments and prevents secondary siRNA production from miRNA targets in Arabidopsis.

PubMed

Branscheid, Anja; Marchais, Antonin; Schott, Gregory; Lange, Heike; Gagliardi, Dominique; Andersen, Stig Uggerhøj; Voinnet, Olivier; Brodersen, Peter

2015-12-15

Small regulatory RNAs are fundamental in eukaryotic and prokaryotic gene regulation. In plants, an important element of post-transcriptional control is effected by 20-24 nt microRNAs (miRNAs) and short interfering RNAs (siRNAs) bound to the ARGONAUTE1 (AGO1) protein in an RNA induced silencing complex (RISC). AGO1 may cleave target mRNAs with small RNA complementarity, but the fate of the resulting cleavage fragments remains incompletely understood. Here, we show that SKI2, SKI3 and SKI8, subunits of a cytoplasmic cofactor of the RNA exosome, are required for degradation of RISC 5', but not 3'-cleavage fragments in Arabidopsis. In the absence of SKI2 activity, many miRNA targets produce siRNAs via the RNA-dependent RNA polymerase 6 (RDR6) pathway. These siRNAs are low-abundant, and map close to the cleavage site. In most cases, siRNAs were produced 5' to the cleavage site, but several examples of 3'-spreading were also identified. These observations suggest that siRNAs do not simply derive from RDR6 action on stable 5'-cleavage fragments and hence that SKI2 has a direct role in limiting secondary siRNA production in addition to its function in mediating degradation of 5'-cleavage fragments. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Late winter home range and habitat use of the Virginia northern flying squirrel (Glaucomys sabrinus fuscus)

Treesearch

W. Mark Ford; Kely N. Mertz; Jennifer M. Menzel; Kenneth K. Sturm

2007-01-01

We radio-tracked two male and one female Virginia northern flying squirrels (Glaucomys sabrinus fuscus) in the Allegheny Mountains of West Virginia at Snowshoe Mountain Resort, in winter 2003 and Canaan Valley National Wildlife Refuge in winter 2004, respectively, to document winter home range and habitat use in or near ski areas. Male home range...

String of turquoise: The future of Sacred Mountain Peaks in the southwest U.S.

Treesearch

Linda Moon Stumpff

2011-01-01

The Southwest is the birthplace of wilderness policy in the United States, yet the unique ecological environments of its peaks, cordilleras, and ranges that dot the high desert remain only partially protected. Some areas are relatively secure, yet midcentury Federal policy responded to multiple development pressures, from ski basins to roads, that sliced these peaks...

Using Air Temperature to Quantitatively Predict the MODIS Fractional Snow Cover Retrieval Errors over the Continental US (CONUS)

NASA Technical Reports Server (NTRS)

Dong, Jiarui; Ek, Mike; Hall, Dorothy K.; Peters-Lidard, Christa; Cosgrove, Brian; Miller, Jeff; Riggs, George A.; Xia, Youlong

2013-01-01

In the middle to high latitude and alpine regions, the seasonal snow pack can dominate the surface energy and water budgets due to its high albedo, low thermal conductivity, high emissivity, considerable spatial and temporal variability, and ability to store and then later release a winters cumulative snowfall (Cohen, 1994; Hall, 1998). With this in mind, the snow drought across the U.S. has raised questions about impacts on water supply, ski resorts and agriculture. Knowledge of various snow pack properties is crucial for short-term weather forecasts, climate change prediction, and hydrologic forecasting for producing reliable daily to seasonal forecasts. One potential source of this information is the multi-institution North American Land Data Assimilation System (NLDAS) project (Mitchell et al., 2004). Real-time NLDAS products are used for drought monitoring to support the National Integrated Drought Information System (NIDIS) and as initial conditions for a future NCEP drought forecast system. Additionally, efforts are currently underway to assimilate remotely-sensed estimates of land-surface states such as snowpack information into NLDAS. It is believed that this assimilation will not only produce improved snowpack states that better represent snow evolving conditions, but will directly improve the monitoring of drought.

Multi-omics facilitated variable selection in Cox-regression model for cancer prognosis prediction.

PubMed

Liu, Cong; Wang, Xujun; Genchev, Georgi Z; Lu, Hui

2017-07-15

New developments in high-throughput genomic technologies have enabled the measurement of diverse types of omics biomarkers in a cost-efficient and clinically-feasible manner. Developing computational methods and tools for analysis and translation of such genomic data into clinically-relevant information is an ongoing and active area of investigation. For example, several studies have utilized an unsupervised learning framework to cluster patients by integrating omics data. Despite such recent advances, predicting cancer prognosis using integrated omics biomarkers remains a challenge. There is also a shortage of computational tools for predicting cancer prognosis by using supervised learning methods. The current standard approach is to fit a Cox regression model by concatenating the different types of omics data in a linear manner, while penalty could be added for feature selection. A more powerful approach, however, would be to incorporate data by considering relationships among omics datatypes. Here we developed two methods: a SKI-Cox method and a wLASSO-Cox method to incorporate the association among different types of omics data. Both methods fit the Cox proportional hazards model and predict a risk score based on mRNA expression profiles. SKI-Cox borrows the information generated by these additional types of omics data to guide variable selection, while wLASSO-Cox incorporates this information as a penalty factor during model fitting. We show that SKI-Cox and wLASSO-Cox models select more true variables than a LASSO-Cox model in simulation studies. We assess the performance of SKI-Cox and wLASSO-Cox using TCGA glioblastoma multiforme and lung adenocarcinoma data. In each case, mRNA expression, methylation, and copy number variation data are integrated to predict the overall survival time of cancer patients. Our methods achieve better performance in predicting patients' survival in glioblastoma and lung adenocarcinoma. Copyright © 2017. Published by Elsevier Inc.

Shrub range expansion alters diversity and distribution of soil fungal communities across an alpine elevation gradient.

PubMed

Collins, Courtney G; Stajich, Jason E; Weber, Sören E; Pombubpa, Nuttapon; Diez, Jeffrey M

2018-04-19

Global climate and land use change are altering plant and soil microbial communities worldwide, particularly in arctic and alpine biomes where warming is accelerated. The widespread expansion of woody shrubs into historically herbaceous alpine plant zones is likely to interact with climate to affect soil microbial community structure and function; however, our understanding of alpine soil ecology remains limited. This study aimed to (i) determine whether the diversity and community composition of soil fungi vary across elevation gradients and to (ii) assess the impact of woody shrub expansion on these patterns. In the White Mountains of California, sagebrush (Artemisia rothrockii) shrubs have been expanding upwards into alpine areas since 1960. In this study, we combined observational field data with a manipulative shrub removal experiment along an elevation transect of alpine shrub expansion. We utilized next-generation sequencing of the ITS1 region for fungi and joint distribution modelling to tease apart effects of the environment and intracommunity interactions on soil fungi. We found that soil fungal diversity declines and community composition changes with increasing elevation. Both abiotic factors (primarily soil moisture and soil organic C) and woody sagebrush range expansion had significant effects on these patterns. However, fungal diversity and relative abundance had high spatial variation, overwhelming the predictive power of vegetation type, elevation and abiotic soil conditions at the landscape scale. Finally, we observed positive and negative associations among fungal taxa which may be important in structuring community responses to global change. © 2018 John Wiley & Sons Ltd.

Comprehensive outreach, prevention education, and skin cancer screening for Utah ski resorts.

PubMed

Varedi, Amir; Secrest, Aaron M; Harding, Garrett; Maness, Lori; Branson, Donna; Smith, Kristi; Hull, Christopher M

2018-02-15

Outdoor recreation can lead to substantial sun exposure. Employees of outdoor recreation establishments with extended time outdoors have amplified cumulative exposure to ultraviolet (UV) radiation and an increased risk of skin cancer. The "Sun Safe on the Slopes" program was created by Huntsman Cancer Institute at the University of Utah and the Utah Cancer Action Network to address increased UV exposure and skin cancer risk with free skin cancer screenings, outreach, and prevention education to local ski resorts. Herein, we describe the processes and barriers to implementation of a ski resort skin screening and education program and our 5-year report of the experience and screening data. Nine free skin cancer screenings were held at Utah ski resorts between 2011 and 2016, resulting in the presumptive diagnosis of 38 skin cancers (9.6%) in 394 participants. Behavioral data collected from participants indicates suboptimal sun safety practices, including underuse of sunscreen and protective clothing. Ski resort employees who experience sun exposure during peak hours at high altitudes and UV reflection from the snow are at an increased risk of skin cancer. These data indicate a need for emphasis on sun safety education and screening and can serve as a model for future endeavors.

Negative regulation of BMP signaling by the ski oncoprotein.

PubMed

Luo, Kunxin

2003-01-01

The bone morphogenetic proteins (BMPs) play important roles in the regulation of multiple aspects of vertebrate development. BMPs signal through the cell surface receptors and downstream Smad molecules. Upon stimulation with BMP, Smad1, Smad5, and Smad8 are phosphorylated by the activated BMP receptors, form a complex with Smad4, and translocate into the nucleus, where they regulate the expression of BMP target genes. The activity of this signal pathway can be modulated both by extracellular factors that regulate the binding of BMPs to the receptor and by intracellular proteins that interact with the Smad proteins. We have shown that Ski is an important negative regulator of the Smad proteins. Ski can bind to the BMP-Smad protein complexes in response to BMP and repress their ability to activate BMP target genes through disruption of a functional Smad complex and through recruitment of transcriptional co-repressors. The antagonism of BMP signaling by Ski results in neural specification in Xenopus embryos and inhibition of osteoblast differentiation in mouse bone-marrow stromal progenitor cells. This ability to modulate BMP signaling by Ski may play an important role in the regulation of craniofacial, neuronal, and skeletal muscle development.

SnoN co-repressor binds and represses smad7 gene promoter.

PubMed

Briones-Orta, Marco A; Sosa-Garrocho, Marcela; Moreno-Alvarez, Paola; Fonseca-Sánchez, Miguel A; Macías-Silva, Marina

2006-03-17

SnoN and Ski oncoproteins are co-repressors for Smad proteins and repress TGF-beta-responsive gene expression. The smad7 gene is a TGF-beta target induced by Smad signaling, and its promoter contains the Smad-binding element (SBE) required for a positive regulation by the TGF-beta/Smad pathway. SnoN and Ski co-repressors also bind SBE but regulate negatively smad7 gene. Ski along with Smad4 binds and represses the smad7 promoter, whereas the repression mechanism by SnoN is not clear. Ski and SnoN overexpression inhibits smad7 reporter expression induced through TGF-beta signaling. Using chromatin immunoprecipitation assays, we found that SnoN binds smad7 promoter at the basal condition, whereas after a short TGF-beta treatment for 15-30 min SnoN is downregulated and no longer bound smad7 promoter. Interestingly, after a prolonged TGF-beta treatment SnoN is upregulated and returns to its position on the smad7 promoter, functioning probably as a negative feedback control. Thus, SnoN also seems to regulate negatively the TGF-beta-responsive smad7 gene by binding and repressing its promoter in a similar way to Ski.

Use of non-alpine anthropogenic habitats by American pikas (Ochotona princeps) in western Oregon, USA

USGS Publications Warehouse

Manning, Tom; Hagar, Joan C.

2011-01-01

The American pika (Ochotona princeps Richardson) has long been characterized in field guides and popular literature as an obligate inhabitant of alpine talus and as having relatively low dispersal capability. However, recent work reveals pikas to have broader habitat associations than previously reported. Over a large portion of the western slope of the Cascade Range in Oregon, pikas inhabit relatively low-elevation sites far from alpine areas and frequently occur in rocky man-made habitats such as roadcuts or rock quarries. We present observations of pikas in these previously overlooked habitats and discuss implications for (1) the proposed listing of the American pika as an endangered or threatened species; (2) furthering our understanding of pika population dynamics, habitat associations, and dispersal capabilites; and (3) management of federal, state, and private forest lands.

Alaska research natural areas: 3. Serpentine slide.

Treesearch

G.P. Juday

1992-01-01

The 1730-ha Serpentine Slide Research Natural Area (RNA) is located in central Alaska in the White Mountains National Recreation Area. It is managed by the U.S. Department of the Interior, Bureau of Land Management, Steese-White Mountains District. Serpentine Slide was selected as a Research Natural Area (RNA) because it contains an alpine exposure of serpentinite; a 9...

78 FR 53500 - Petition for Exemption From the Federal Motor Vehicle Theft Prevention Standard; Chrysler

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-29

...) transceiver and a microprocessor and it initiates the ignition process by communicating with the BCM through SKIS. The microprocessor-based SKIS hardware and software also use electronic messages to communicate...

A simulation model for forecasting downhill ski participation

Treesearch

Daniel J. Stynes; Daniel M. Spotts

1980-01-01

The purpose of this paper is to describe progress in the development of a general computer simulation model to forecast future levels of outdoor recreation participation. The model is applied and tested for downhill skiing in Michigan.

Adaptive downhill skiing in children with cerebral palsy: effect on gross motor function.

PubMed

Sterba, John A

2006-01-01

The study was designed to examine the effect of adaptive downhill skiing (ADS) on gross motor function in children with spastic cerebral palsy. One girl and four boys participated (mean age = eight years, five months). All were ambulatory. Participants' Gross Motor Function Measure (GMFM) classifications were: Level I (n = 2); Level II (n = 2); Level III (n = 1). ADS was conducted for a 10-week period at one ski resort. Each participant had the same ski instructor. GMFM was obtained every five weeks: beginning five weeks before ADS instruction and continuing to 10 weeks after ADS instruction. After 10 weeks of ADS GMFM-D, and GMFM-Total Score increased 5.4% (p = 0.022) and 3.2% (p = 0.035), respectively, and remained increased 10 weeks after ADS. ADS could be recommended by clinicians as a recreational activity for the gross motor rehabilitation of ambulatory children with spastic cerebral palsy.

Cross-Country Skiing Injuries and Training Methods.

PubMed

Nagle, Kyle B

2015-01-01

Cross-country skiing is a low injury-risk sport that has many health benefits and few long-term health risks. Some concern exists that cross-country skiing may be associated with a higher incidence of atrial fibrillation; however, mortality rates among skiers are lower than those among the general population. While continuing to emphasize aerobic and anaerobic training, training methods also should promote ski-specific strength training to increase maximum force and its rate of delivery and to build muscular endurance to maintain that power through a race. Multiple tests are available to monitor training progress. Which tests are most appropriate depends on the specific events targeted. In addition to laboratory-based tests, there also are many simpler, more cost-effective tests, such as short time trials, that can be used to monitor training progress and predict performance particularly at the junior skier level where access and cost may be more prohibitive.

Impact of a thermokarst lake on the soil hydrological properties in permafrost regions of the Qinghai-Tibet Plateau, China.

PubMed

Gao, Zeyong; Niu, Fujun; Wang, Yibo; Luo, Jing; Lin, Zhanju

2017-01-01

The formation of thermokarst lakes can degrade alpine meadow ecosystems through changes in soil water and heat properties, which might have an effect on the regional surface water and groundwater processes. In this study, a typical thermokarst lake was selected in the Qinghai-Tibet Plateau (QTP), and the ecological index (S L ) was used to divide the affected areas into extremely affected, severely affected, medium-affected, lightly affected, and non-affected areas, and soil hydrological properties, including saturated hydraulic conductivity and soil water-holding capacity, were investigated. The results showed that the formation of a thermokarst lake can lead to the degradation of alpine meadows, accompanied by a change in the soil physiochemical and hydrological properties. Specifically, the soil structure turned towards loose soil and the soil nutrients decreased from non-affected areas to severely affected areas, but the soil organic matter and available potassium increased slightly in the extremely affected areas. Soil saturated hydraulic conductivity showed a 1.7- to 4.1-fold increase in the lake-surrounding areas, and the highest value (401.9cmd -1 ) was detected in the severely affected area. Soil water-holding capacity decreased gradually during the transition from the non-affected areas to the severely affected areas, but it increased slightly in the extremely affected areas. The principal component analysis showed that the plant biomass was vital to the changes in soil hydrological properties. Thus, the vegetation might serve as a link between the thermokarst lake and soil hydrological properties. In this particular case, it was concluded that the thermokarst lake adversely affected the regional hydrological services in the alpine ecosystem. These results would be useful for describing appropriate hydraulic parameters with the purpose of modeling soil water transportation more accurately in the Qinghai-Tibet Plateau. Copyright © 2016 Elsevier B.V. All rights reserved.

Take-off analysis of the Olympic ski jumping competition (HS-106m).

PubMed

Virmavirta, Mikko; Isolehto, Juha; Komi, Paavo; Schwameder, Hermann; Pigozzi, Fabio; Massazza, Giuseppe

2009-05-29

The take-off phase (approximately 6m) of the jumps of all athletes participating in the individual HS-106m hill ski jumping competition at the Torino Olympics was filmed with two high-speed cameras. The high altitude of the Pragelato ski jumping venue (1600m) and slight tail wind in the final jumping round were expected to affect the results of this competition. The most significant correlation with the length of the jump was found in the in-run velocity (r=0.628, p<0.001, n=50). This was a surprise in Olympic level ski jumping, and suggests that good jumpers simply had smaller friction between their skis and the in-run tracks and/or the aerodynamic quality of their in-run position was better. Angular velocity of the hip joint of the best jumpers was also correlated with jumping distance (r=0.651, p<0.05, n=10). The best jumpers in this competition exhibited very different take-off techniques, but still they jumped approximately the same distance. This certainly improves the interests in ski jumping among athletes and spectators. The comparison between the take-off techniques of the best jumpers showed that even though the more marked upper body movement creates higher air resistance, it does not necessarily result in shorter jumping distance if the exposure time to high air resistance is not too long. A comparison between the first and second round jumps of the same jumpers showed that the final results in this competition were at least partly affected by the wind conditions.

Protective Effect of Triptolide against Glomerular Mesangial Cell Proliferation and Glomerular Fibrosis in Rats Involves the TGF-β1/Smad Signaling Pathway

PubMed Central

Cao, Yingjie; Huang, Xinzhong; Fan, Yaping; Chen, Xiaolan

2015-01-01

Triptolide as a main active ingredient of Tripterygium wilfordii is known to be exerting anti-inflammatory, marked immunosuppressive, and podocyte-protective effects. In this study, we investigated the protective effect of triptolide in kidney disease. Rat glomerular mesangial cells were randomly divided into three groups: (1) control group, (2) TGF-β1 (10 μg/mL) group, and (3) triptolide group (triptolide 10 μg/L + TGF-β1 10 μg/L). Sixty male Sprague-Dawley rats were randomly divided into three groups: (1) control group, (2) chronic serum sickness glomerulonephritis model group, and (3) triptolide (0.2 mg/kg·d) group. Reverse transcription PCR was used to assess Ski and Smad3 mRNA expression in the mesangial cells and renal tissues. Western blotting was used to determine Ski and Smad3 protein expressions. Laser confocal fluorescence microscopy was used to observe the subcellular localization of Smad3 and Ski proteins in the mesangial cells. Triptolide inhibited the TGF-β1-induced proliferation of mesangial cells. It significantly upregulated Ski protein expression and downregulated Smad3 mRNA and protein expressions in a time-dependent manner. Laser confocal fluorescence microscopy detected high Smad3 fluorescence intensity in the cytoplasm and low Smad3 and high Ski fluorescence intensity in the nucleus. By upregulating Ski protein expression triptolide decreased the extent of fibrosis by affecting the TGF-β1/Smad3 signaling pathway. PMID:26451157

Sphingosine kinase inhibitor suppresses IL-18-induced interferon-gamma production through inhibition of p38 MAPK activation in human NK cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheon, Soyoung; Song, Seok Bean; Jung, Minkyung

2008-09-12

Natural killer (NK) cells play an important role in the innate immune response. Interleukin-18 (IL-18) is a well-known interferon-gamma (IFN-{gamma} inducing factor, which stimulates immune response in NK and T cells. Sphingosine kinase (SPHK) catalyzes the formation of sphingosine 1-phosphate (S1P), which acts as a second messenger to function as an anti-apoptotic factor and proliferation stimulator of immune cells. In this study, to elucidate whether SPHK is involved in IL-18-induced IFN-{gamma} production, we measured IL-18-induced IFN-{gamma} production after pre-treatment with SPHK inhibitor (SKI) in NK-92MI cells. We found that IL-18-induced IFN-{gamma} expression was blocked by SKI pre-treatment in both mRNAmore » and protein levels. In addition, the increased IFN-{gamma} production by stimulation with IL-18 is mediated through both SPHK and p38 MAPK. To determine the upstream signals of SKI and p38 MAPK in IL-18-induced IFN-{gamma} production, phosphorylation levels of p38 MAPK was measured after SKI pre-treatment. As a result, inhibition of SPHK by SKI blocked phosphorylation of p38 MAPK, showing that SPHK activation by IL-18 is an upstream signal of p38 MAPK activation. Inhibition of SPHK by SKI also inhibited IL-18-induced IFN-{gamma} production in human primary NK cells. In conclusion, SPHK activation is an essential factor for IL-18-induced IFN-{gamma} production via p38 MAPK.« less

High-mountain lakes as a hotspot of dissolved organic matter production in a changing climate

NASA Astrophysics Data System (ADS)

Abood, P. H.; Williams, M. W.; McKnight, D. M.; Hood, E. H.

2004-12-01

Changes in climate may adversely affect mountain environments before downstream ecosystems are affected. Steep topography, thin soils with limited extent, sparse vegetation, short growing seasons, and climatic extremes (heavy snowfalls, cold temperatures, high winds), all contribute to the sensitivity of high mountain environments to perturbations. Here we evaluate the role of oligatrophic high-elevation lakes as "hot spots" of aquatic production that may respond to changes in temperature, precipitation amount, and pollution deposition faster and more directly than co-located terrestrial ecosystems. Our research was conducted in the Rocky Mountains, USA. Water samples were collected for dissolved organic carbon (DOC), other solutes, and water isotopes over the course of the runoff season along a longitudinal transect of North Boulder Creek in the Colorado Front Range from the continental divide and alpine areas to downstream forested systems. Sources of DOC were evaluated using chemical fractionation with XAD-8 resins and fluorescence spectroscopy. There was net DOC production in the two alpine lakes but not for the forested subalpine lake. Oxygen-18 values showed that water residence times in lakes increased dramatically in late summer compared to snowmelt. Chemical fractionation of DOC showed there was a increase in the non-humic acid content across the summer of 2003 at all elevations, with alpine waters showing greater increases than subalpine waters. The fluorescence properties of DOC and water isotopes suggested that DOC in aquatic systems was primarily derived from terrestrial precursor material during snowmelt. However, fluorescence properties of DOC in high-elevation lakes on the recession limb of the hydrograph suggest DOC derived from algal and microbial biomass in the lakes was a more important source of DOC in late summer and fall. Alpine lakes produced 14 times more DOC on unit area basis compared to the surrounding terrestrial ecosystems. We hypothesize that much of the authochthonous production is a result of algal growth in alpine lakes caused by the increases in nitrogen deposition from wetfall.

76 FR 62785 - Nordica USA, Provisional Acceptance of a Settlement Agreement and Order

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-11

... (``Skis''). The binding plates on the skis could crack or break causing the skier to lose control or fall.... This knowledge required Nordica to immediately inform the Commission of the defect and risk associated...

Fundamental considerations in ski binding analysis.

PubMed

Mote, C D; Hull, M L

1976-01-01

1. The static adjustment of a ski binding by hand or by available machines is only an adjustment and is neither a static nor a dynamic evaluation of the binding design. Bindings of different design with identical static adjustments will perform differently in environments in which the forces are static or dynamic. 2. The concept of binding release force is a useful measure of binding adjustment, but it is inappropriate as a criterion for binding evaluation. First, it does not direct attention toward the injury causing mechanism, strain, or displacement in the leg. Second, it is only part of the evaluation in dynamic problems. 3. The binding release decision in present bindings is displacement controlled. The relative displacement of the boot and ski is the system variable. For any specified relative displacement the binding force can be any of an infinite number of possibilities determined by the loading path. 4. The response of the leg-ski system to external impulses applied to the ski is independent of the boot-ski relative motion as long as the boot recenters quickly in the binding. Response is dependent upon the external impulse plus system inertia, damping and stiffness. 5. When tested under half sinusoidal forces applied to a test ski, all bindings will demonstrate static and impulse loading regions. In the static region the force drives the binding to a relative release displacement. In the impulse region the initial velocity of the ski drives the binding to a release displacement. 6. The transition between the static and impulse loading regions is determined by the binding's capacity to store and dissipate energy along the principal loading path. Increased energy capacity necessitates larger external impulses to produce release. 7. In all bindings examined to date, the transmitted leg displacement or strain at release under static loading exceeds leg strain under dynamic or impact loading. Because static loading is responsible for many injuries, a skier should be able to release his bindings in every mode by simply pulling or twisting his foot outward. If that cannot be done without injury, the skier has identified for himself one type of fall that will result in injury. 8. And lastly, a little advice from Ben Franklin--"Carelessness does more harm than a want of knowledge."

How to Drive a Car on a Snowy Slope

ERIC Educational Resources Information Center

Ogawara, Yasuo

2016-01-01

When I was a freshman at Tokyo University of Science, my senpai (upper-class student mentor) took me to a certain skiing ground in his car, which was equipped with standard tires. He tried to enter the parking area there, but his car could not climb a short slope leading to the entrance. I would like to describe here how he dealt with the problem…

Integrated HPV genomes tend to integrate in gene desert areas in the CaSki, HeLa, and SiHa cervical cancer cell lines.

PubMed

Diao, Ming-Kun; Liu, Chu-Yi; Liu, Hong-Wei; Li, Jin-Tao; Li, Fan; Mehryar, Mohammadreza Mohammadzad; Wang, Yang-Junqi; Zhan, Shao-Bing; Zhou, Yu-Bai; Zhong, Ru-Gang; Zeng, Yi

2015-04-15

The integration preferences of human papillomavirus (HPV) have been intensively studied and contested over recent years. To disclose the integration preferences of high-risk HPV in cervical cancer, HPV transcriptional sites and features in different cervical cancer cell lines were identified. In this study, three cervical cancer cell lines (CaSki, HeLa, and SiHa) were subjected for HPV genome status determination by amplification of papillomavirus oncogene transcripts (APOT) assay. The numbers of viral copies in human genomes and numbers of viral-human fusion mRNAs in three HPV-integrated cervical cancer cell lines were measured and analysed. The results revealed that the gene desert region 8q24 of the HPV type 18 integrated HeLa cell line and the 13q21-22 region of the HPV type 16 integrated CaSki and SiHa cell lines were hotspots for HPV integration, and the numbers of viral copies in the human genomes of the three cell lines that we detected were not in accordance with those reported in previous studies. Integration of the HPV genome into the host cell chromosome suggests that persistent HPV infection is vital for malignant cell transformation and carcinogenesis. This study provides information to benefit health care professionals seeking more comprehensive and accurate diagnostics for HPV-related disease"? Please check, and amend as necessary. Copyright © 2015 Elsevier Inc. All rights reserved.

Fatal fall into a volcanic fumarole.

PubMed

Cantrell, Lee; Young, Michael

2009-01-01

Fatalities secondary to inhalation of volcanic gases in the United States have rarely been reported. We report the deaths of 3 ski patrol members at a popular California ski resort. After a snowstorm, ski patrol members were fencing off a well-known volcanic fumarole when the snow around the vent collapsed. Two members slid into the deep hole and rapidly lost consciousness. A third member carrying oxygen descended into the hole and also lost consciousness. A fourth member affixed an oxygen mask, but still lost consciousness upon descent. The 3 initial victims expired at the scene, while the fourth victim survived. Autopsy results for all 3 were consistent with a suffocation/asphyxiation death. In the case described, the involved fumarole is a well-known source of toxic gases. Atmospheric sampling data dating back decades demonstrate that carbon dioxide levels typically range from 97% to 99%, nitrogen gas from 1% to 3%, and hydrogen sulfide from .004% to .07%. Other gases in smaller concentrations include oxygen, hydrogen, and carbon monoxide. Given the rapidity with which our victims lost consciousness and the historical data available on the Mammoth Mountain Fumarole (MMF), it is plausible that our patients suffered from acute asphyxiation, although the contribution of the directly toxic effects of the gases involved cannot be ruled out. During winter months, snow can build up and disguise volcanic vents and potentially trap toxic fumes to form dangerous, gas-filled pits. Recognition of such potential hazards is essential when working in or venturing into volcanically active areas during the winter.

Contexts for change in alpine tundra

USGS Publications Warehouse

Malanson, George P.; Rose, Jonathan P.; Schroeder, P. Jason; Fagre, Daniel B.

2011-01-01

Because alpine tundra is responding to climate change, a need exists to understand the meaning of observed changes. To provide context for such interpretation, the relevance of niche and neutral theories of biogeography and the continuum and classification approaches to biogeographic description are assessed. Two extensive studies of alpine tundra, from the Indian Peaks area, Colorado and Glacier National Park, Montana, are combined. The data are ordinated to describe relations. The pattern that emerges is one of a continuum of vegetation, but with the distinctions one might expect from distant sites. The relationships of the similarity of vegetation on all possible pairs of sites to the environmental differences and geographic distances are analyzed using Mantel correlations. Because distance and environmental differences in climate between the two sites are correlated, partial correlations are weak but still significant. More advanced analyses are suggested for this environment prior to interpretation of monitoring efforts such as GLORIA.

Seasonal characteristics of flood regimes across the Alpine-Carpathian range.

PubMed

Parajka, J; Kohnová, S; Bálint, G; Barbuc, M; Borga, M; Claps, P; Cheval, S; Dumitrescu, A; Gaume, E; Hlavčová, K; Merz, R; Pfaundler, M; Stancalie, G; Szolgay, J; Blöschl, G

2010-11-17

The aim of this paper is to analyse the differences in the long-term regimes of extreme precipitation and floods across the Alpine-Carpathian range using seasonality indices and atmospheric circulation patterns to understand the main flood-producing processes. This is supported by cluster analyses to identify areas of similar flood processes, both in terms of precipitation forcing and catchment processes. The results allow to isolate regions of similar flood generation processes including southerly versus westerly circulation patterns, effects of soil moisture seasonality due to evaporation and effects of soil moisture seasonality due to snow melt. In many regions of the Alpine-Carpathian range, there is a distinct shift in flood generating processes with flood magnitude as evidenced by a shift from summer to autumn floods. It is argued that the synoptic approach proposed here is valuable in both flood analysis and flood estimation.

Aquatic indicator bacteria in the high alpine zone.

PubMed

Stuart, S A; McFeters, G A; Schillinger, J E; Stuart, D G

1976-02-01

Selected waters from the high alpine zone within Grand Teton National Park, Wyoming, were analyzed for populations of indicator bacteria during the past three summers to determine the influence of various factors on the quality of these waters. In general the water quality was not significantly influenced by the presence or absence of human visitors but rather by the nature of the biological community through which the streams flowed. A minority of the coliforms that were recovered from all of the sites proved to be fecal coliforms. The fecal streptococci isolated were identified as the species that were found primarily in the fecal material of the native rodent and moose populations. It is concluded that management questions that relate to the carrying capacity of alpine areas should be approached with the aid of other biological parameters along with levels of indicator bacteria in the streams.

Modelling plant species distribution in alpine grasslands using airborne imaging spectroscopy

PubMed Central

Pottier, Julien; Malenovský, Zbyněk; Psomas, Achilleas; Homolová, Lucie; Schaepman, Michael E.; Choler, Philippe; Thuiller, Wilfried; Guisan, Antoine; Zimmermann, Niklaus E.

2014-01-01

Remote sensing using airborne imaging spectroscopy (AIS) is known to retrieve fundamental optical properties of ecosystems. However, the value of these properties for predicting plant species distribution remains unclear. Here, we assess whether such data can add value to topographic variables for predicting plant distributions in French and Swiss alpine grasslands. We fitted statistical models with high spectral and spatial resolution reflectance data and tested four optical indices sensitive to leaf chlorophyll content, leaf water content and leaf area index. We found moderate added-value of AIS data for predicting alpine plant species distribution. Contrary to expectations, differences between species distribution models (SDMs) were not linked to their local abundance or phylogenetic/functional similarity. Moreover, spectral signatures of species were found to be partly site-specific. We discuss current limits of AIS-based SDMs, highlighting issues of scale and informational content of AIS data. PMID:25079495

Sochi, Russia Winter Olympic Sites Mountain Cluster

NASA Image and Video Library

2014-02-05

The 2014 Winter Olympic ski runs may be rated double black diamond, but theyre not quite as steep as they appear in this image acquired by NASA Terra spacecraft, of the skiing and snowboarding sites for the Sochi Winter Olympic Games.

Biomechanical and energetic determinants of technique selection in classical cross-country skiing.

PubMed

Pellegrini, Barbara; Zoppirolli, Chiara; Bortolan, Lorenzo; Holmberg, Hans-Christer; Zamparo, Paola; Schena, Federico

2013-12-01

Classical cross-country skiing can be performed using three main techniques: diagonal stride (DS), double poling (DP), and double poling with kick (DK). Similar to other forms of human and animal gait, it is currently unclear whether technique selection occurs to minimize metabolic cost or to keep some mechanical factors below a given threshold. The aim of this study was to find the determinants of technique selection. Ten male athletes roller skied on a treadmill at different slopes (from 0° to 7° at 10km/h) and speeds (from 6 to 18km/h at 2°). The technique preferred by skiers was gathered for every proposed condition. Biomechanical parameters and metabolic cost were then measured for each condition and technique. Skiers preferred DP for skiing on the flat and they transitioned to DK and then to DS with increasing slope steepness, when increasing speed all skiers preferred DP. Data suggested that selections mainly occur to remain below a threshold of poling force. Second, critically low values of leg thrust time may limit the use of leg-based techniques at high speeds. A small role has been identified for the metabolic cost of locomotion, which determined the selection of DP for flat skiing. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of a skiing intervention on the psycho-physiological reactivity and recovery in the elderly.

PubMed

Finkenzeller, T; Müller, E; Amesberger, G

2011-08-01

This study determined the effects of a skiing intervention lasting 12 weeks on the psycho-physiological reactivity to and recovery from mental stressors in individuals who are 60+ years of age. In accordance with the cross-stressor hypothesis, it was assumed that a skiing intervention optimizes psycho-physiological pre-conditions for coping with stress. A cognitive task was used to investigate stress-induced changes (reactivity) in the high-frequency (HF) component of the heart rate variability (HRV) and in the skin conductance level (SCL) as well as recovery from this stressor. The intervention group demonstrated a significant increase in maximal oxygen consumption that was not accompanied by alterations in HRV at rest. In comparison with the control group, there was no difference in the alteration of the reactivity and recovery in the HF component and in the SCL after completing the training. The findings indicate that neither the psycho-physiological reactivity nor the recovery was influenced by the skiing intervention. It may be speculated that the intensity of the skiing intervention was too low to induce such adaptations. Therefore, further studies are encouraged to enhance the duration and intensity of the exercises to achieve adaptations of the autonomous nervous system of elderly individuals. © 2011 John Wiley & Sons A/S.

Cardiorespiratory endurance evaluation using heart rate analysis during ski simulator exercise and the Harvard step test in elementary school students.

PubMed

Lee, Hyo Taek; Roh, Hyo Lyun; Kim, Yoon Sang

2016-01-01

[Purpose] Efficient management using exercise programs with various benefits should be provided by educational institutions for children in their growth phase. We analyzed the heart rates of children during ski simulator exercise and the Harvard step test to evaluate the cardiopulmonary endurance by calculating their post-exercise recovery rate. [Subjects and Methods] The subjects (n = 77) were categorized into a normal weight and an overweight/obesity group by body mass index. They performed each exercise for 3 minutes. The cardiorespiratory endurance was calculated using the Physical Efficiency Index formula. [Results] The ski simulator and Harvard step test showed that there was a significant difference in the heart rates of the 2 body mass index-based groups at each minute. The normal weight and the ski-simulator group had higher Physical Efficiency Index levels. [Conclusion] This study showed that a simulator exercise can produce a cumulative load even when performed at low intensity, and can be effectively utilized as exercise equipment since it resulted in higher Physical Efficiency Index levels than the Harvard step test. If schools can increase sport durability by stimulating students' interests, the ski simulator exercise can be used in programs designed to improve and strengthen students' physical fitness.

Electromyography and the study of sports movements: a review.

PubMed

Clarys, J P; Cabri, J

1993-10-01

Within electromyography (EMG), a particular specialty has been developed wherein the aim is to use EMG for the study of muscular function and co-ordination. This area of research is usually called kinesiological EMG. The general aims of kinesiological EMG are to analyse the function and co-ordination of muscles in different movements and postures, in healthy subjects as well as in the disabled, in skilled actions as well as during training, in humans as well as in animals, under laboratory conditions as well as during daily or vocational activities. This is often done by a combination of electromyographical and kinesiological or biomechanical measurement techniques. Because there are over 400 skeletal muscles in the human body and both irregular and complex involvement of the muscles may occur in neuromuscular diseases and in voluntary occupational or sports movements, it is impossible to sample all of the muscles of the entire body during the performance of complex motor skills. In addition, the measurement of kinesiological EMG in sport and specific field circumstances, such as the track and/or soccer field, the alpine ski slope, the swimming pool and the ice rink, demands a specific technological and methodological approach, adaptable to both the field and the sport circumstances. Sport movement techniques and skills, training approaches and methods, ergonomic verification of the human-machine interaction have, amongst others, a highly specialized muscular activity in common. The knowledge of such muscular action in all its aspects, its evaluation and its feedback should allow for the optimization of movement, of sports materials, of training possibilities and, in the end, of sports performance. Drawing conclusions from a review of the EMG research of 32 sports, covering over 100 different complex skills, including methodological approaches, is an impossible task. We have attempted to set standards concerning the EMG methodology at the beginning of this review. Electromyography and sports is a vast area and a complete review is impossible, as information will be found scattered in many different journals, including those on the sports sciences, ergonomics, biomechanics, applied physiology, in different congress proceedings, and so on. Consequently, many important aspects and possibly important publications may have been omitted from this review.

Managing Algorithmic Skeleton Nesting Requirements in Realistic Image Processing Applications: The Case of the SKiPPER-II Parallel Programming Environment's Operating Model

NASA Astrophysics Data System (ADS)

Coudarcher, Rémi; Duculty, Florent; Serot, Jocelyn; Jurie, Frédéric; Derutin, Jean-Pierre; Dhome, Michel

2005-12-01

SKiPPER is a SKeleton-based Parallel Programming EnviRonment being developed since 1996 and running at LASMEA Laboratory, the Blaise-Pascal University, France. The main goal of the project was to demonstrate the applicability of skeleton-based parallel programming techniques to the fast prototyping of reactive vision applications. This paper deals with the special features embedded in the latest version of the project: algorithmic skeleton nesting capabilities and a fully dynamic operating model. Throughout the case study of a complete and realistic image processing application, in which we have pointed out the requirement for skeleton nesting, we are presenting the operating model of this feature. The work described here is one of the few reported experiments showing the application of skeleton nesting facilities for the parallelisation of a realistic application, especially in the area of image processing. The image processing application we have chosen is a 3D face-tracking algorithm from appearance.

Ecosystem services-based SWOT analysis of protected areas for conservation strategies.

PubMed

Scolozzi, Rocco; Schirpke, Uta; Morri, Elisa; D'Amato, Dalia; Santolini, Riccardo

2014-12-15

An ecosystem services-based SWOT analysis is proposed in order to identify and quantify internal and external factors supporting or threatening the conservation effectiveness of protected areas. The proposed approach concerns both the ecological and the social perspective. Strengths and weaknesses, opportunities and threats were evaluated based on 12 selected environmental and socio-economic indicators for all terrestrial Italian protected areas, belonging to the Natura 2000 network, and for their 5-km buffer area. The indicators, used as criteria within a multi-criteria assessment, include: core area, cost-distance between protected areas, changes in ecosystem services values, intensification of land use, and urbanization. The results were aggregated for three biogeographical regions, Alpine, Continental, and Mediterranean, indicating that Alpine sites have more opportunities and strengths than Continental and Mediterranean sites. The results call attention to where connectivity and land-use changes may have stronger influence on protected areas, in particular, whereas urbanization or intensification of agriculture may hamper conservation goals of protected areas. The proposed SWOT analysis provides helpful information for a multiple scale perspective and for identifying conservation priorities and for defining management strategies to assure biodiversity conservation and ecosystem services provision. Copyright © 2014 Elsevier Ltd. All rights reserved.

Metals in Racomitrium lanuginosum from Arctic (SW Spitsbergen, Svalbard archipelago) and alpine (Karkonosze, SW Poland) tundra.

PubMed

Wojtuń, Bronisław; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J

2018-05-01

Arctic-alpine tundra habitats are very vulnerable to the input of relatively small amounts of xenobiotics, and thus their level in such areas must be carefully controlled. Therefore, we collected the terrestrial widespread moss Racomitrium lanuginosum (Hedw.) Brid. in Spitsbergen in the Arctic moss lichen tundra and, for comparison, in the Arctic-alpine tundra in the Karkonosze (SW Poland). Concentrations of the elements Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Na, Ni, Pb, V, and Zn in this species and in the parent rock material were measured. We tested the following hypothesis: R. lanuginosum from Spitsbergen contains lower metal levels than the species from the Karkonosze collected at altitudes influenced by long-range transport from former Black Triangle industry. Principal component and classification analysis (PCCA) ordination revealed that mosses of Spitsbergen were distinguished by a significantly higher Na concentration of marine spray origin and mosses of Karkonosze were distinguished by significantly higher concentrations of Cd, Cr, Cu, Fe, Hg, Li, Mn, Pb, V, and Zn probably from long-range atmospheric transport. The influence of the polar station with a waste incinerator resulted in significantly higher Co, Li, and Ni concentrations in neighbouring mosses in comparison with this species from other sites. This investigation contributes to the use of R. lanuginosum as a bioindicator for metal contamination in Arctic and alpine tundra regions characterised by severe climate habitats with a restricted number of species. This moss enables the control of pollution usually brought solely by long-range atmospheric transport in high mountains as well as in Arctic areas.