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While running provides an accessible form of cardiovascular stimulus, many runners report lower extremity musculoskeletal injuries. Additionally, runners who develop overuse injuries, such as tibial stress fractures, also have hig...
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While running provides an accessible form of cardiovascular stimulus, many runners report lower extremity musculoskeletal injuries. Additionally, runners who develop overuse injuries, such as tibial stress fractures, also have higher loading rates (LR) and impact forces.
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Individuals with Down syndrome (DS) exhibit reduced aerobic capacity with reduced peak heart rate (HRpeak). This condition is often coexistent with higher level of obesity compared to individuals without DS. The purpose of this st...
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Individuals with Down syndrome (DS) exhibit reduced aerobic capacity with reduced peak heart rate (HRpeak). This condition is often coexistent with higher level of obesity compared to individuals without DS. The purpose of this study is to investigate the effects of obesity and Down syndrome (DS) on peak heart rate (HRpeak) and peak oxygen consumption (VO2peak) in children and adults both with and without intellectual disabilities (ID)s. VO2peak and HRpeak from individualized treadmill tests on 654 individuals were analyzed. Body mass index was used to categorize individuals' weight status using standard cut-offs. DS groups had the lowest HRpeak (167 bpm +/- 14, p < 0.05) compared to individuals with (183 bpm +/- 12) without ID (187 bpm +/- 12). Obesity did not affect HRpeak among adults and children with DS. VO2peak was lower among individuals with DS (25.2 mL/kg/min +/- 63, p < 0.05) when compared individuals with (37.0 mL/kg/min +/- 10.5) and without ID (36.1 mL/kg/min +/- 10.4). Obese adults with DS had lower VO2peak (24.3 mL/kg/min +/- 6.9, p= 0.001) compared to the normal weight (26.7 +/- 7.1 mL/kg/min) and overweight groups (27.0 mL/kg/min +/- 6.1) with DS. Conversely, in children, obesity level did not impact VO2peak in individuals with DS. Our results suggest that DS attenuates both VO2peak and HRpeak, regardless of obesity status and age group. However, obesity was associated with lower VO2peak in all adults, but not in children with DS. (C) 2014 Elsevier Ltd. All rights reserved.
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We investigate an intertemporal model with an exhaustible resource inflow which exhibits a single peak in consumption on the path of development. The peak follows the date at which net investment is zero. The "top" of consumption ...
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We investigate an intertemporal model with an exhaustible resource inflow which exhibits a single peak in consumption on the path of development. The peak follows the date at which net investment is zero. The "top" of consumption is higher and flatter and peaks later when the discount rate is lower. "Low" endowments of the exhaustible resource stock (and "high" discount rates) are associated with strictly declining consumption paths.
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Residential electrification of transport and heat is changing consumption and its characteristics significantly. Previous studies have demonstrated the impact of socio-techno-economic determinants on residential consumption. Howev...
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Residential electrification of transport and heat is changing consumption and its characteristics significantly. Previous studies have demonstrated the impact of socio-techno-economic determinants on residential consumption. However, they fail to capture the distributional characteristics of such consumer groups, which impact network planning and flexibility assessment. Using actual residential electricity consumption profile data for 720,000 households in Denmark, we demonstrate that heat pumps are more likely to influence aggregated peak consumption than electric vehicles. At the same time, other socio-economic factors, such as occupancy, dwelling area and income, show little impact. Comparing the extrapolation of a comprehensive rollout of heat pumps or electric vehicles indicates that the most common consumer category deploying heat pumps has 14% more maximum consumption during peak load hours, 46% more average consumption and twice the higher median compared to households owning an electric vehicle. Electric vehicle show already flexibility with coincidence factors that ranges between 5 and 15% with a maximum of 17% whereas heat pumps are mostly baseload. The detailed and holistic outcomes of this study support flexibility assessment and grid planning in future studies but also the operation of flexible technologies.
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摘要 :
Residential electrification of transport and heat is changing consumption and its characteristics significantly. Previous studies have demonstrated the impact of socio-techno-economic determinants on residential consumption. Howev...
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Residential electrification of transport and heat is changing consumption and its characteristics significantly. Previous studies have demonstrated the impact of socio-techno-economic determinants on residential consumption. However, they fail to capture the distributional characteristics of such consumer groups, which impact network planning and flexibility assessment. Using actual residential electricity consumption profile data for 720,000 households in Denmark, we demonstrate that heat pumps are more likely to influence aggregated peak consumption than electric vehicles. At the same time, other socio-economic factors, such as occupancy, dwelling area and income, show little impact. Comparing the extrapolation of a comprehensive rollout of heat pumps or electric vehicles indicates that the most common consumer category deploying heat pumps has 14% more maximum consumption during peak load hours, 46% more average consumption and twice the higher median compared to households owning an electric vehicle. Electric vehicle show already flexibility with coincidence factors that ranges between 5 and 15% with a maximum of 17% whereas heat pumps are mostly baseload. The detailed and holistic outcomes of this study support flexibility assessment and grid planning in future studies but also the operation of flexible technologies.
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On the basis of the registered indications of the water meter, a study on the size and variability of water consumption on the WULS campus in the academic years 2012/16 is presented. The average specific water consumption at a tim...
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On the basis of the registered indications of the water meter, a study on the size and variability of water consumption on the WULS campus in the academic years 2012/16 is presented. The average specific water consumption at a time when classes are implemented amounted to 26.6 dm3 per student per day for full-time studies student and 19.7 dm3 per student per day for the student part-time studies. During the holiday season, the rates are lower at 18.4 and 11.8 dm3 per student per day, respectively. These ratios were determined without taking the water consumption in the dorms into account. The daily peaking factor amounted (Nd) to 1.36, while the hourly peaking factor (Nh), reached 1.71. Within the week cycle, the highest water consumption was observed in Tuesdays and the lowest – in Sundays. The average Tuesday demands are 40% higher than the Sunday demands. The water consumption peaks during the day occur between 11 a.m. and 1 p.m. as well as 11 p.m. and 1 a.m. The hourly structure of the water distribution in the WULS-SGGW campus is similar to the weekend structure of water distribution in multi-family residential buildings, with the exception of the later occurrence of the evening summit.
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This study aimed to determine if systemic O-2 utilization (Vo2) and tissue oxygen extraction (deoxyhemoglobin [HHb]) in the vastus lateralis (VL), gastrocnemius (GAST), and prefrontal cortex were different during exercise between ...
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This study aimed to determine if systemic O-2 utilization (Vo2) and tissue oxygen extraction (deoxyhemoglobin [HHb]) in the vastus lateralis (VL), gastrocnemius (GAST), and prefrontal cortex were different during exercise between short-term trained (STT, 6-24 months) and long-term trained (LTT, >5 years) young women while controlling for current training load. Thirteen STT and 13 LTT participants completed ramp incremental (RI) and square-wave constant load (SWCL) tests on a cycle ergometer. In LTT compared with STT: (a) (V)over dotO(2) was higher during the RI (p = 0.024) and SWCL (p = 0.001) tests; (b) HHb in the VL (p = 0.044) and GAST (p = 0.027) was higher in the RI test; and (c) there were significant group X intensity interactions for Vol in the SWCL test. The additional years of aerobic training in LTT compared with STT (LTT 7.1 +/- 1.9 vs. STT 1.5 +/- 0.4 years) resulted in higher Vol and HHb in the VL and GAST. These results indicate that in young women, independent of current training load, systemic Vol and peripheral muscle 02 extraction during exercise continues to increase beyond 24 months of aerobic training.
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Cardiopulmonary exercise testing (CPXT) is a promising tool for predicting 2-year cardiac death or ventricular assist device (VAD) implantation in patients assigned to INTERMACS profile 4-7. However, CPXT is not available in all h...
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Cardiopulmonary exercise testing (CPXT) is a promising tool for predicting 2-year cardiac death or ventricular assist device (VAD) implantation in patients assigned to INTERMACS profile 4-7. However, CPXT is not available in all hospitals. We evaluated 130 patients < 65 years old with advanced heart failure assigned to INTERMACS profile 4-7 who underwent CPXT. CPXT scores (0-8 points), which we created recently, and the Seattle HF Model (SHFM) scores were both significant predictors of 2-year cardiac death or VAD implantation (14 events) by Cox-regression analysis (P < 0.05 for both) and had comparable areas under the curve (AUCs) in receiver operating characteristic analyses (0.811 vs. 0.737, P > 0.05). The combination score: age < 46 years and serum sodium concentration < 137 mEq/L, both of which were significant predictors of cardiac death or VAD implantation by uni/multivariate Cox-regression analyses, had a significantly higher AUC than did CPXT scores (0.909, P < 0.05). In a validation study, the AUC of the combination score was comparable with that of SHFM among 52 patients < 65 years old receiving adaptive servo-ventilator treatment (0.753 vs. 0.794, P > 0.05). In conclusion, VAD indication may be discussed without CPXT in patients < 65 years old with INTERMACS profile 4-7 at least in the current Japanese situation.
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Purpose The first aim of this experiment was to evaluate the appropriateness of linear and non-linear (allometric) models to scale peak aerobic power (oxygen consumption) against body mass. The possibilities that oxygen consumptio...
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Purpose The first aim of this experiment was to evaluate the appropriateness of linear and non-linear (allometric) models to scale peak aerobic power (oxygen consumption) against body mass. The possibilities that oxygen consumption would scale allometrically across the complete metabolic range, and that the scaling exponents would differ significantly between basal and maximal-exercise states, were then evaluated. It was further hypothesised that the scaling exponent would increase in a stepwise manner with elevations in exercise intensity. Finally, the utility of applying the scaling exponent derived for peak aerobic power to another population sample was evaluated. Methods Basal, steady-state walking and peak (treadmill) oxygen-consumption data were measured using 60 relatively homogeneous men (18-40 year; 56.0-117.1 kg), recruited across five mass classes. Linear and allometric regressions were applied, with the utility of each scaling method evaluated. Results Oxygen consumption scaled allometrically with body mass across the complete metabolic range, and was always superior to both ratiometric analysis and linear regression. The scaling exponent increased significantly from rest (mass(0.57)) to maximal exercise (mass(0.75); P 0.05). When used with an historical database, the maximal-exercise exponent successfully removed the mass bias. Conclusion It has been demonstrated that the oxygen consumption of healthy humans scales allometrically with body mass across the entire metabolic range. Moreover, only two scaling exponents (rest and exercise) were required to produce mass-independent outcomes from those data. Accordingly, ratiometric and linear regression analyses are not recommended as scaling methods.
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Demand-based charges have been employed as a tool intended to reduce electricity users' maximum demand but there is a lack of consensus regarding their efficacy. One reason for this may be the diversity in the flexibility potentia...
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Demand-based charges have been employed as a tool intended to reduce electricity users' maximum demand but there is a lack of consensus regarding their efficacy. One reason for this may be the diversity in the flexibility potential of different types of users. This study explores the flexibility potential of different types of electricity consumers in the small to medium-sized commercial sector (35-63A) in response to a compulsory demand charge. The objective is to characterize varying levels of flexibility with respect to different types of commercial users with different load patterns. A multivariate clustering technique was used to group commercial users with comparable load patterns based on a year of hourly data before the tariff change was introduced. This method was used to: (1) match users from the intervention area and reference area with similar load patterns, without losing any user data, and (2) compare how users with different load patterns react differently to the tariff change. We found clear distinctions in the types of commercial users in each cluster and their response to the tariff, demonstrating the extent to which demand flexibility may be dependent on the nature of an organization's activities and its respective load patterns. The highest demand flexibility was found in clusters which had a large share of users in the IT sector, commerce and public administration. The lowest demand flexibility was found in the real estate and education sectors. Future research should further investigate these variations and explore the possibilities of tailoring interventions to the specific types of users.
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