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Cold regions involve hydrological processes that are not often addressed appropriately in hydrological models. The Cold Regions Hydrological Modelling platform (CRHM) was initially developed in 1998 to assemble and explore the hydrological understanding developed from a series of research basins spanning Canada and international cold regions. Hydrological processes and basin response in cold regions are simulated in a flexible, modular, object-oriented, multiphysics platform. The CRHM platform allows for multiple representations of forcing data interpolation and extrapolation, hydrological model spatial and physical process structures, and parameter values. It is well suited for model falsification, algorithm intercomparison and benchmarking, and has been deployed for basin hydrology diagnosis, prediction, land use change and water quality analysis, climate impact analysis and flood forecasting around the world. This paper describes CRHM’s capabilities, and the insights derived by applying the model in concert with process hydrology research and using the combined information and understanding from research basins to predict hydrological variables, diagnose hydrological change and determine the appropriateness of model structure and parameterisations.

Objective: To investigate associations between physical activity and risk factors for cardiovascular disease (CVD), subclinical atherosclerosis, and disease activity in patients with early and long-standing rheumatoid arthritis (RA). Method: This cross-sectional study included 84 patients with early and 37 with long-standing RA (disease duration, mean ± sd: 1.4 ± 0.4 and 16.3 ± 2.3 years, respectively). Physical activity was measured using a combined accelerometer and heart-rate monitor. Further assessments were disease activity (erythrocyte sedimentation rate, Disease Activity Score in 28 joints), functional ability (Health Assessment Questionnaire), risk factors for CVD (blood lipids, i.e. triglycerides, high-density lipoprotein, low-density lipoprotein; blood glucose, blood pressure, sleeping heart rate, waist circumference, body mass index, and body fat), and subclinical atherosclerosis (pulse-wave velocity, augmentation index, and carotid intima–media thickness). Results: Physical activity variables did not differ between patients with early and long-standing RA. However, 37% of the patients with early and 43% of those with long-standing RA did not reach the World Health Organization’s recommended levels of moderate to vigorous physical activity (MVPA). In a final multiple regression model, adjusted for age, gender, disease duration, and activity monitor wear time, higher total physical activity was associated with lower body fat and higher functional ability. With the same adjustments, more time spent in MVPA was associated with lower high-density lipoprotein and lower sleeping heart rate. Conclusions: Physical activity was associated with more favourable risk factors for CVD. However, many patients were physically inactive, stressing the importance of promoting physical activity in RA.

Objective: To investigate associations between physical activity and risk factors for cardiovascular disease (CVD), subclinical atherosclerosis, and disease activity in patients with early and long-standing rheumatoid arthritis (RA). Method: This cross-sectional study included 84 patients with early and 37 with long-standing RA (disease duration, mean ± sd: 1.4 ± 0.4 and 16.3 ± 2.3 years, respectively). Physical activity was measured using a combined accelerometer and heart-rate monitor. Further assessments were disease activity (erythrocyte sedimentation rate, Disease Activity Score in 28 joints), functional ability (Health Assessment Questionnaire), risk factors for CVD (blood lipids, i.e. triglycerides, high-density lipoprotein, low-density lipoprotein; blood glucose, blood pressure, sleeping heart rate, waist circumference, body mass index, and body fat), and subclinical atherosclerosis (pulse-wave velocity, augmentation index, and carotid intima–media thickness). Results: Physical activity variables did not differ between patients with early and long-standing RA. However, 37% of the patients with early and 43% of those with long-standing RA did not reach the World Health Organization’s recommended levels of moderate to vigorous physical activity (MVPA). In a final multiple regression model, adjusted for age, gender, disease duration, and activity monitor wear time, higher total physical activity was associated with lower body fat and higher functional ability. With the same adjustments, more time spent in MVPA was associated with lower high-density lipoprotein and lower sleeping heart rate. Conclusions: Physical activity was associated with more favourable risk factors for CVD. However, many patients were physically inactive, stressing the importance of promoting physical activity in RA.

Objective: To investigate associations between physical activity and risk factors for cardiovascular disease (CVD), subclinical atherosclerosis, and disease activity in patients with early and long-standing rheumatoid arthritis (RA). Method: This cross-sectional study included 84 patients with early and 37 with long-standing RA (disease duration, mean ± sd: 1.4 ± 0.4 and 16.3 ± 2.3 years, respectively). Physical activity was measured using a combined accelerometer and heart-rate monitor. Further assessments were disease activity (erythrocyte sedimentation rate, Disease Activity Score in 28 joints), functional ability (Health Assessment Questionnaire), risk factors for CVD (blood lipids, i.e. triglycerides, high-density lipoprotein, low-density lipoprotein; blood glucose, blood pressure, sleeping heart rate, waist circumference, body mass index, and body fat), and subclinical atherosclerosis (pulse-wave velocity, augmentation index, and carotid intima–media thickness). Results: Physical activity variables did not differ between patients with early and long-standing RA. However, 37% of the patients with early and 43% of those with long-standing RA did not reach the World Health Organization’s recommended levels of moderate to vigorous physical activity (MVPA). In a final multiple regression model, adjusted for age, gender, disease duration, and activity monitor wear time, higher total physical activity was associated with lower body fat and higher functional ability. With the same adjustments, more time spent in MVPA was associated with lower high-density lipoprotein and lower sleeping heart rate. Conclusions: Physical activity was associated with more favourable risk factors for CVD. However, many patients were physically inactive, stressing the importance of promoting physical activity in RA.

Objective: To investigate associations between physical activity and risk factors for cardiovascular disease (CVD), subclinical atherosclerosis, and disease activity in patients with early and long-standing rheumatoid arthritis (RA). Method: This cross-sectional study included 84 patients with early and 37 with long-standing RA (disease duration, mean ± sd: 1.4 ± 0.4 and 16.3 ± 2.3 years, respectively). Physical activity was measured using a combined accelerometer and heart-rate monitor. Further assessments were disease activity (erythrocyte sedimentation rate, Disease Activity Score in 28 joints), functional ability (Health Assessment Questionnaire), risk factors for CVD (blood lipids, i.e. triglycerides, high-density lipoprotein, low-density lipoprotein; blood glucose, blood pressure, sleeping heart rate, waist circumference, body mass index, and body fat), and subclinical atherosclerosis (pulse-wave velocity, augmentation index, and carotid intima–media thickness). Results: Physical activity variables did not differ between patients with early and long-standing RA. However, 37% of the patients with early and 43% of those with long-standing RA did not reach the World Health Organization’s recommended levels of moderate to vigorous physical activity (MVPA). In a final multiple regression model, adjusted for age, gender, disease duration, and activity monitor wear time, higher total physical activity was associated with lower body fat and higher functional ability. With the same adjustments, more time spent in MVPA was associated with lower high-density lipoprotein and lower sleeping heart rate. Conclusions: Physical activity was associated with more favourable risk factors for CVD. However, many patients were physically inactive, stressing the importance of promoting physical activity in RA.

Objective: To investigate associations between physical activity and risk factors for cardiovascular disease (CVD), subclinical atherosclerosis, and disease activity in patients with early and long-standing rheumatoid arthritis (RA). Method: This cross-sectional study included 84 patients with early and 37 with long-standing RA (disease duration, mean ± sd: 1.4 ± 0.4 and 16.3 ± 2.3 years, respectively). Physical activity was measured using a combined accelerometer and heart-rate monitor. Further assessments were disease activity (erythrocyte sedimentation rate, Disease Activity Score in 28 joints), functional ability (Health Assessment Questionnaire), risk factors for CVD (blood lipids, i.e. triglycerides, high-density lipoprotein, low-density lipoprotein; blood glucose, blood pressure, sleeping heart rate, waist circumference, body mass index, and body fat), and subclinical atherosclerosis (pulse-wave velocity, augmentation index, and carotid intima–media thickness). Results: Physical activity variables did not differ between patients with early and long-standing RA. However, 37% of the patients with early and 43% of those with long-standing RA did not reach the World Health Organization’s recommended levels of moderate to vigorous physical activity (MVPA). In a final multiple regression model, adjusted for age, gender, disease duration, and activity monitor wear time, higher total physical activity was associated with lower body fat and higher functional ability. With the same adjustments, more time spent in MVPA was associated with lower high-density lipoprotein and lower sleeping heart rate. Conclusions: Physical activity was associated with more favourable risk factors for CVD. However, many patients were physically inactive, stressing the importance of promoting physical activity in RA.

BACKGROUND/OBJECTIVES: Easy-to-use and accurate methods to assess free-living activity energy expenditure (AEE) in preschool children are required. The aims of this study in healthy preschool children were to (a) evaluate the ability of the wrist-worn ActiGraph wGT3x-BT to predict free-living AEE and (b) assess wear compliance using a 7-day, 24-h protocol. SUBJECTS/METHODS: Participants were 40 Swedish children (5.5 +/- 0.2 years) in the Mobile-based intervention intended to stop obesity in preschoolers (MINISTOP) obesity prevention trial. Total energy expenditure (TEE) was assessed using the doubly labeled water method during 14 days. AEE was calculated as (TEEx0.9) minus predicted basal metabolic rate. The ActiGraph accelerometer was worn on the wrist for 7 days and outputs used were mean of the daily and awake filtered vector magnitude (mean VM total and mean VM waking). RESULTS: The ActiGraph was worn for 7 (n = 34, 85%), 6 (n = 4, 10%), 5 (n = 1, 2.5%) and 4 (n = 1, 2.5%) days (a valid day was. 600 awake minutes). Alone, mean VM total and mean VM waking were able to explain 14% (P = 0.009) and 24% (P = 0.001) of the variation in AEE, respectively. By incorporating fat and fat-free mass in the models 58% (mean VM total) and 62% (mean VM waking) in the variation of AEE was explained (P amp;lt; 0.001). CONCLUSIONS: The wrist-worn ActiGraph wGT3x-BT in combination with body composition variables explained up to the 62% of the variation in AEE. Given the high wear compliance, the wrist-worn ActiGraph has the potential to provide useful information in studies where physical activity in preschool children is measured., Funding Agencies|SNF Swedish Nutrition Foundation; Swedish Research Council [2012-2883]; Swedish Research Council for Health, Working Life and Welfare [2012-0906]; Bo and Vera Axson Johnsons Foundation; Karolinska Institutet; Henning and Johan Throne-Holst Foundation

In this study we quantified the sensitivity of the snow to climate warming in selected mountain sites having a Mediterranean climate, including the Pyrenees in Spain and Andorra, the Sierra Nevada in Spain and California (USA), the Atlas in Morocco, and the Andes in Chile. Meteorological observations from high elevations were used to simulate the snow energy and mass balance (SEMB) and calculate its sensitivity to climate. Very different climate sensitivities were evident amongst the various sites. For example, reductions of 9–19% and 6–28 days in the mean snow water equivalent (SWE) and snow duration, respectively, were found per C increase. Simulated changes in precipitation (± 20%) did not affect the sensitivities. The Andes and Atlas Mountains have a shallow and cold snowpack, and net radiation dominates the SEMB; and explains their relatively low sensitivity to climate warming. The Pyrenees and USA Sierra Nevada have a deeper and warmer snowpack, and sensible heat flux is more important in the SEMB; this explains the much greater sensitivities of these regions. Differences in sensitivity help explain why in regions where climate models project relatively greater temperature increases and drier conditions by 2050 (such as the Spanish Sierra Nevada and the Moroccan Atlas Mountains), the decline in snow accumulation and duration is similar to other sites (such as the Pyrenees and the USA Sierra Nevada), where models project stable precipitation and more attenuated warming. The snowpack in the Andes (Chile) exhibited the lowest sensitivity to warming, and is expected to undergo only moderate change (a decrease of <12% in mean SWE, and a reduction of < 7 days in snow duration under RCP 4.5). Snow accumulation and duration in the other regions are projected to decrease substantially (a minimum of 40% in mean SWE and 15 days in snow duration) by 2050.

In June 2013, excessive rainfall associated with an intense weather system triggered severe flooding in southern Alberta, which became the costliest natural disaster in Canadian history. This article provides an overview of the climatological aspects and large-scale hydrometeorological features associated with the flooding event based upon information from a variety of sources, including satellite data, upper air soundings, surface observations and operational model analyses. The results show that multiple factors combined to create this unusually severe event. The event was characterized by a slow-moving upper level low pressure system west of Alberta, blocked by an upper level ridge, while an associated well-organized surface low pressure system kept southern Alberta, especially the eastern slopes of the Rocky Mountains, in continuous precipitation for up to two days. Results from air parcel trajectory analysis show that a significant amount of the moisture originated from the central Great Plains, transported into Alberta by a southeasterly low level jet. The event was first dominated by significant thunderstorm activity, and then evolved into continuous precipitation supported by the synoptic-scale low pressure system. Both the thunderstorm activity and upslope winds associated with the low pressure system produced large rainfall amounts. A comparison with previous similar events occurring in the same region suggests that the synoptic-scale features associated with the 2013 rainfall event were not particularly intense; however, its storm environment was the most convectively unstable. The system also exhibited a relatively high freezing level, which resulted in rain, rather than snow, mainly falling over the still snow-covered mountainous areas. Melting associated with this rain-on-snow scenario likely contributed to downstream flooding. Furthermore, above-normal snowfall in the preceding spring helped to maintain snow in the high-elevation areas, which facilita

BACKGROUND: Existing knowledge on associations of physical activity (PA) and sedentary behavior (SB) with body composition and physical fitness in preschoolers is limited. OBJECTIVE: To examine associations of PA and SB with body composition and physical fitness in healthy Swedish 4-year-old children. METHODS: We utilized baseline data collected in 2014 for the population-based MINISTOP trial (n = 307). Light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA), moderate-to-vigorous PA (MVPA) and SB were measured using accelerometry (ActiGraph-wGT3x-BT). Body composition was measured using air-displacement plethysmography, and physical fitness (that is, cardiorespiratory fitness, lower and upper body muscular strength and motor fitness) was measured using the PREFIT fitness test battery. Multiple linear regression models adjusted for relevant confounders, and in addition, isotemporal substitution models were applied. RESULTS: Greater MVPA was associated with lower fat mass percent (%FM, P = 0.015), and greater VPA and MVPA were associated with higher fat-free mass index (FFMI, P = 0.002 and P = 0.011). In addition, greater VPA and MVPA were associated with higher scores for all physical fitness tests (P = 0.042 to Pamp;lt;0.001). The results for MVPA were primarily due to VPA. SB was associated with weaker handgrip strength (P = 0.031) when PA was not adjusted, but after adjusting also for VPA, the significant association disappeared (P = 0.25). Substituting 5 min per day of SB, LPA or MPA with 5 min per day of VPA was associated with higher FFMI and better scores for cardiorespiratory fitness and motor fitness. Correspondingly, substituting 5 min per day of VPA with SB or LPA was associated with weaker performance for lower muscular strength. CONCLUSIONS: Time spent on VPA was associated with higher FFMI and better physical fitness. The results suggest that promoting VPA may be important to improve childhood body composition and physical fit, Funding Agencies|Swedish Research Council [2012-2883]; Swedish Research Council for Health, Working Life and Welfare [2012-0906]; Bo and Vera Axson Johnsons Foundation; Karolinska Institutet; Juho Vainio Foundation; Spanish Ministry of Economy and Competitiveness [RYC-2010-05957, RYC-2011-09011, BES-2014-068829]; Johan Throne-Holsts Foundation

The aim of this study was to analyse the effect of slope aspect on the response of snowpack to climate warming in the Pyrenees. For this purpose, data available from five automatic weather stations were used to simulate the energy and mass balance of snowpack, assuming different magnitudes of an idealized climate warming (upward shifting of 1, 2 and 3 °C the temperature series). Snow energy and mass balance were simulated using the Cold Regions Hydrological Modelling platform (CRHM). CRHM was used to create a model that enabled correction of the all-wave incoming radiation fluxes from the observation sites for various slope aspects (N, NE, E, SE, S, SW,W,NW and flat areas), which enabled assessment of the differential impact of climate warming on snow processes on mountain slopes. The results showed that slope aspect was responsible for substantial variability in snow accumulation and the duration of the snowpack. Simulated variability markedly increased with warmer temperature conditions. Annual maximum snow accumulation (MSA) and annual snowpack duration (ASD) showed marked sensitivity to a warming of 1 °C. Thus, the sensitivity of the MSA in flat areas ranged from 11 to 17 % per degree C amongst the weather stations, and the ASD ranged from 11 to 20 days per degree C. There was a clear increase in the sensitivity of the snowpack to climate warming on those slopes that received intense solar radiation (S, SE and SW slopes) compared with those slopes where the incident radiation was more limited (N, NE and NW slopes). The sensitivity of the MSA and the ASD increased as the temperature increased, particularly on the most irradiated slopes. Large interannual variability was also observed. Thus, with more snow accumulation and longer duration the sensitivity of the snowpack to temperature decreased, especially on south-facing slopes.

Impressive power densities have been demonstrated for GaN-on-SiC based high-power high-frequency transistors, although further gains can be achieved by further minimizing the device thermal resistance. A significant 10-30% contribution to the total device thermal resistance originates from the high defect density AlN nucleation layer at the GaN/SiC interface. This thermal resistance contribution was successfully reduced by performing systematic growth optimization, investigating growth parameters including: Substrate pretreatment temperature, growth temperature and deposition time. Interfacial thermal resistance, characterized by time resolved Raman thermography measurements AlGaN/GaN HEMT structures, were minimized by using a substrate pretreatment and growth temperature of 1200 °C. Reducing the AlN thickness from 105 nm (3.3×10-8W/m2K) to 35 nm (3.3×10-8 W/m2K), led to a ~2.5× interfacial thermal resistance reduction and the lowest value reported for a standard AlGaN/GaN HEMT structure.

Aims Overweight and obesity during pregnancy raise the risk of gestational diabetes and birth complications. Lifestyle factors such as physical activity may decrease these risks through beneficial effects on systemic glucose homeostasis. Here we examined physical activity patterns and their relationships with measures of glucose homeostasis in late pregnancy compared to non-pregnant women. Methods Normal weight and overweight women without diabetes (N=108; aged 25-35 years) were studied; 35 were pregnant (in gestational weeks 28-32) and 73 were non-pregnant. An oral glucose tolerance test was conducted from which insulin sensitivity and β-cell response were estimated. Physical activity was measured during 10-days of free-living using a combined heart rate sensor and accelerometer. Total (TEE), resting (REE), and physical activity (PAEE) energy expenditure were measured using doubly-labeled water and expired gas indirect calorimetry. Results Total activity (counts/day) was associated with a reduced first-phase insulin response in both pregnant (r=-0.47; 95% CI: -0.70- to -0.15) and non-pregnant women (r=-0.36; 95% CI: -0.56- to -0.12). Pregnant women were estimated to have secreted more insulin (p=0.002) and had lower fasting glucose than non-pregnant women (p<0.0001). Measures of overall physical activity intensity were similar in both groups (p=0.547), but pregnant women spent more time sedentary (p<0.0001), less time in moderate-to-vigorous intensity activity (p<0.0001), had lower objectively measured total activity, and had lower physical activity energy expenditure (PAEE) than non-pregnant women (p=0.045). Conclusions Our findings suggest that physical activity conveys similar benefits on glucose homeostasis in pregnant and non-pregnant women, despite differences in subcomponents of physical activity.

New laboratory measurements using an Electron Beam Ion Trap (EBIT) and an x-ray microcalorimeter are presented for the n=3 to n=2 Fe XVII emission lines in the 15 {\AA} to 17 {\AA} range, along with new theoretical predictions for a variety of electron energy distributions. This work improves upon our earlier work on these lines by providing measurements at more electron impact energies (seven values from 846 to 1185 eV), performing an in situ determination of the x-ray window transmission, taking steps to minimize the ion impurity concentrations, correcting the electron energies for space charge shifts, and estimating the residual electron energy uncertainties. The results for the 3C/3D and 3s/3C line ratios are generally in agreement with the closest theory to within 10%, and in agreement with previous measurements from an independent group to within 20%. Better consistency between the two experimental groups is obtained at the lowest electron energies by using theory to interpolate, taking into account the significantly different electron energy distributions. Evidence for resonance collision effects in the spectra is discussed. Renormalized values for the absolute cross sections of the 3C and 3D lines are obtained by combining previously published results, and shown to be in agreement with the predictions of converged R-matrix theory. This work establishes consistency between results from independent laboratories and improves the reliability of these lines for astrophysical diagnostics. Factors that should be taken into account for accurate diagnostics are discussed, including electron energy distribution, polarization, absorption/scattering, and line blends., Comment: 29 pages, including 7 figures

New laboratory measurements using an Electron Beam Ion Trap (EBIT) and an x-ray microcalorimeter are presented for the n=3 to n=2 Fe XVII emission lines in the 15 {\AA} to 17 {\AA} range, along with new theoretical predictions for a variety of electron energy distributions. This work improves upon our earlier work on these lines by providing measurements at more electron impact energies (seven values from 846 to 1185 eV), performing an in situ determination of the x-ray window transmission, taking steps to minimize the ion impurity concentrations, correcting the electron energies for space charge shifts, and estimating the residual electron energy uncertainties. The results for the 3C/3D and 3s/3C line ratios are generally in agreement with the closest theory to within 10%, and in agreement with previous measurements from an independent group to within 20%. Better consistency between the two experimental groups is obtained at the lowest electron energies by using theory to interpolate, taking into account the significantly different electron energy distributions. Evidence for resonance collision effects in the spectra is discussed. Renormalized values for the absolute cross sections of the 3C and 3D lines are obtained by combining previously published results, and shown to be in agreement with the predictions of converged R-matrix theory. This work establishes consistency between results from independent laboratories and improves the reliability of these lines for astrophysical diagnostics. Factors that should be taken into account for accurate diagnostics are discussed, including electron energy distribution, polarization, absorption/scattering, and line blends., Comment: 29 pages, including 7 figures

The Ground Accelerated Space Platform (GASP) is a plan for propelling large masses into space and into specified orbits within the solar system. Terrestrial bombardment or orbital missions are also possible. The plan involves acceleration of a vehicle to the escape velocity in a long, underground vertical (or inclined) tube by the release of nuclear energy into propellant fluid behind the vehicle. Terminal guidance is provided by solid propellant rockets carried within the vehicle. GASP launching involves exposure to high accelerations - 2,000 to 4,000g for lighter payloads and 500 to 1,000g for heavier payloads, on space missions. For terrestrial missions, accelerations are reduced to the order of 100g. Cost comparisons for payload in orbit between GASP and probable future rocket developments are made. Construction costs and methods are presented for several typical locations, involving different construction techniques. Probable operating costs and the cost of a small-scale test facility are included. (Author)

In June 2013, excessive rainfall associated with an intense weather system triggered severe flooding in southern Alberta, which became the costliest natural disaster in Canadian history. This article provides an overview of the climatological aspects and large-scale hydrometeorological features associated with the flooding event based upon information from a variety of sources, including satellite data, upper air soundings, surface observations and operational model analyses. The results show that multiple factors combined to create this unusually severe event. The event was characterized by a slow-moving upper level low pressure system west of Alberta, blocked by an upper level ridge, while an associated well-organized surface low pressure system kept southern Alberta, especially the eastern slopes of the Rocky Mountains, in continuous precipitation for up to two days. Results from air parcel trajectory analysis show that a significant amount of the moisture originated from the central Great Plains, transported into Alberta by a southeasterly low level jet. The event was first dominated by significant thunderstorm activity, and then evolved into continuous precipitation supported by the synoptic-scale low pressure system. Both the thunderstorm activity and upslope winds associated with the low pressure system produced large rainfall amounts. A comparison with previous similar events occurring in the same region suggests that the synoptic-scale features associated with the 2013 rainfall event were not particularly intense; however, its storm environment was the most convectively unstable. The system also exhibited a relatively high freezing level, which resulted in rain, rather than snow, mainly falling over the still snow-covered mountainous areas. Melting associated with this rain-on-snow scenario likely contributed to downstream flooding. Furthermore, above-normal snowfall in the preceding spring helped to maintain snow in the high-elevation areas, which facilita