This study examined the peak physical and physiological (heart rate) performance intensities anda... more This study examined the peak physical and physiological (heart rate) performance intensities andassociated decrements in elite soccer referees during match play. Design: Longitudinal study. Methods: Physical performancevariables and heart rate were analyzed during 457 matches across two seasons. Differences between halves, and the rate ofdecline in peak performance intensities across moving average durations of 1-10 minutes were assessed using linear mixed models and power-law analysis, respectively. Results: Large significant differences were observed between halves for mean total distance, mean velocity, mean heart rate, and percentage of maximal heart rate (p ≤ 0.05; r = 0.51-0.64). Peak intensities (p ≤ 0.05; r = 0.15-0.17) and the rate of decline (p < 0.001; r = 0.17-0.37) were significantly higher in the 2 nd half compared to the 1 st half, for relative total distance, relative high-intensity running and mean velocity. The rate of decline was significantly greater in the 2 nd half than the 1 st half for relative distance covered by high-intensity acceleration (>2 m/s-2 /min), deceleration (<-2 m/s-2 /min), and relative mean heart rate (p < 0.001; r = 0.28-0.61). Elite soccer referees might have experienced transient fatigue during match play, as relative high-intensity running immediately following the most intense 5-minute period significantly declined by 61.2% (p< 0.001; r = 0.94), and was 16.2% lower than the mean 5-minute period (p < 0.001; r = 0.34). Conclusions: Increased physical and physiological demands during match play, with associated declines in the second half and transient signs of fatigue throughout the match, supports the inclusion of high-intensity interval and endurance training programs to prepare soccer referees for the intensity demands and peak performance outcomes of match play.
Introduction: Textile experts perform extensive close labor in small, densely packed workstations... more Introduction: Textile experts perform extensive close labor in small, densely packed workstations, exposing themselves to a variety of ocular and vision-related issues. Objectives: To find the frequency of asthenopic symptoms among tailors and to associate their asthenopia with their working environment profile which includes many factors such as lighting conditions, position blubs, working hours, working days, and taking breaks during work. Methodology: This cross-sectional study was conducted over five months from October 2018 to February 2019 and it included 325 sewing professionals of garments (tailors) from the tailoring market of Rawalpindi. Study subjects were interviewed through a structured questionnaire that included demographic, working profiles, and symptoms of asthenopia. Data were analyzed by using SPSS version 21. The Chi-square test was used to check the association of dependent and independent variables. Results: A total of 325 subjects were included in this study....
In this study, NIMROD simulations are performed to investigate the effects of massive Helium gas ... more In this study, NIMROD simulations are performed to investigate the effects of massive Helium gas injection level on the induced disruption on EAST tokamak. It is demonstrated in simulations that two different scenarios of plasma cooling (complete cooling and partial cooling) take place for different amounts of injected impurities. For the impurity injection above a critical level, a single MHD activity is able to induce a complete core temperature collapse. For impurity injection below the critical level, a series of multiple minor disruptions occur before the complete thermal quench (TQ).
2018 IEEE 21st International Multi-Topic Conference (INMIC), 2018
Hybrid power generation system not only reduces our dependency on fossil fuel power generation st... more Hybrid power generation system not only reduces our dependency on fossil fuel power generation stations but also helps us to meet the peak load demand. Renewable energy resources such as solar and wind in hybrid power generation system can play a vital role in reducing fuel cost and emission of conventional power generation system. In this paper, energy scheduling of hybrid power generation system is carried out by considering the fuel cost of thermal power generators and their emissions. Different optimization techniques, genetic algorithm, pattern search method, and interior point algorithm are used in this paper to optimally schedule the energy required from the thermal power generators to meet the load demand by taking into account the power from the renewable energy resources. These optimization techniques are compared in respect of fuel cost, emissions and computational time complexity. Interior point algorithm outperforms patter search method and genetic algorithm. It achieves more reduced fuel cost and emission as compared to pattern search method and genetic algorithm.
YouTube is the second most popular website in the world and is increasingly being used as a platf... more YouTube is the second most popular website in the world and is increasingly being used as a platform for disseminating health information. Our aim was to evaluate the content-quality and audience engagement of YouTube videos pertaining to the SARS (severe acute respiratory syndrome)-CoV-2 virus which causes the Coronavirus Disease 2019 (COVID-19), during the early phase of the pandemic. We chose the first 30 videos for seven different search phrases: "2019 nCoV," "SARS CoV-2," "COVID-19 virus," "coronavirus treatment," "coronavirus explained," "what is the coronavirus" and "coronavirus information." Video contents were evaluated by two independent medical students with more than 5 years of experience using the DISCERN instrument. Qualitative data, quantitative data and upload source for each video was noted for a quality and audience engagement analysis. Out of the total 210 videos, 137 met our inclusion criteria and were evaluated. The mean DISCERN score was 31.33 out of 75 possible points, which indicates that the quality of YouTube videos on COVID-19 is currently poor. There was excellent reliability between the two raters (intraclass correlation coefficient = 0.96). 55% of the videos discussed prevention, 49% discussed symptoms and 46% discussed the spread of the virus. Most of the videos were uploaded by news channels (50%) and education channels (40%). The quality of YouTube videos on SARS-CoV-2 and COVID-19 is poor, however, we have listed the top-quality videos in our article as they may be effective tools for patient education during the pandemic.
Progress in Computational Fluid Dynamics, An International Journal, 2019
In the present study, buoyancy driven flows of water and air in very high aspect ratio (12-48) ho... more In the present study, buoyancy driven flows of water and air in very high aspect ratio (12-48) horizontal rectangular enclosures are studied numerically for Rayleigh numbers ranging from 10 3 to 10 7 using open-source CFD tools to obtain natural convection heat transfer coefficients which are then compared with established empirical correlations based on experimental results. This study has been motivated by the finding that hardly any CFD-based literature on very high aspect ratio rectangular enclosures exist and also by the fact that such enclosures have numerous applications in solar thermal systems such as solar collectors, solar passive heating/cooling systems, and solar stills, etc. It has been reported in the literature that at high aspect ratios, the numerical solution suffers from convergence issues. In the present study, using Code_Saturne as flow solver, the convergence issues have not risen and the error between numerical and experimental results increases with an increase in Rayleigh number bounded by maximum relative error of approximately 8%.
The ability of surfactant aggregate−H 2 O interfaces to control the regioselectivity of Diels−Ald... more The ability of surfactant aggregate−H 2 O interfaces to control the regioselectivity of Diels−Alder reactions has been investigated. Cycloadditions of surfactant 1,3-dienes 2-[[3-(dimethyldodecylsilyl )-1,3-butadien-2-yl]thio]-N,N,N-trimethyl-1-ethanaminium iodide (1a) and 6-[[3-( ...
... John ~ oolcock &amp;#x27; and Abdullah Zafar Indiana University of Pennsylvania Indiana, ... more ... John ~ oolcock &amp;#x27; and Abdullah Zafar Indiana University of Pennsylvania Indiana, PA 15705 ... mass in grams; C is the balance calibration constant; R is the digital display reading when the filled sample tube is in place; R, is the digital display reading for the empty sam-ple tube; x ...
The complex NiBr 2 (2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2) (1) was prepared... more The complex NiBr 2 (2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2) (1) was prepared from the ligand 2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2 (3) and NiBr 2. Paramagnetic 1 was characterized by combustion analyses, 1 H and 13 C NMR spectroscopy, Vis-NIR spectroscopy, measurement of its magnetic susceptibility, and single-crystal X-ray diffraction. The crystal structure of 1 features octahedral coordination of Ni(II) with axial bromides and fully extended interdigitated alkyl chains. There are significant differences between the solid state structures of 1 and NiBr 2 (2-C 6 H 12 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 6 H 12-2) (2), a previously reported homologue.
This study examined the peak physical and physiological (heart rate) performance intensities anda... more This study examined the peak physical and physiological (heart rate) performance intensities andassociated decrements in elite soccer referees during match play. Design: Longitudinal study. Methods: Physical performancevariables and heart rate were analyzed during 457 matches across two seasons. Differences between halves, and the rate ofdecline in peak performance intensities across moving average durations of 1-10 minutes were assessed using linear mixed models and power-law analysis, respectively. Results: Large significant differences were observed between halves for mean total distance, mean velocity, mean heart rate, and percentage of maximal heart rate (p ≤ 0.05; r = 0.51-0.64). Peak intensities (p ≤ 0.05; r = 0.15-0.17) and the rate of decline (p < 0.001; r = 0.17-0.37) were significantly higher in the 2 nd half compared to the 1 st half, for relative total distance, relative high-intensity running and mean velocity. The rate of decline was significantly greater in the 2 nd half than the 1 st half for relative distance covered by high-intensity acceleration (>2 m/s-2 /min), deceleration (<-2 m/s-2 /min), and relative mean heart rate (p < 0.001; r = 0.28-0.61). Elite soccer referees might have experienced transient fatigue during match play, as relative high-intensity running immediately following the most intense 5-minute period significantly declined by 61.2% (p< 0.001; r = 0.94), and was 16.2% lower than the mean 5-minute period (p < 0.001; r = 0.34). Conclusions: Increased physical and physiological demands during match play, with associated declines in the second half and transient signs of fatigue throughout the match, supports the inclusion of high-intensity interval and endurance training programs to prepare soccer referees for the intensity demands and peak performance outcomes of match play.
Introduction: Textile experts perform extensive close labor in small, densely packed workstations... more Introduction: Textile experts perform extensive close labor in small, densely packed workstations, exposing themselves to a variety of ocular and vision-related issues. Objectives: To find the frequency of asthenopic symptoms among tailors and to associate their asthenopia with their working environment profile which includes many factors such as lighting conditions, position blubs, working hours, working days, and taking breaks during work. Methodology: This cross-sectional study was conducted over five months from October 2018 to February 2019 and it included 325 sewing professionals of garments (tailors) from the tailoring market of Rawalpindi. Study subjects were interviewed through a structured questionnaire that included demographic, working profiles, and symptoms of asthenopia. Data were analyzed by using SPSS version 21. The Chi-square test was used to check the association of dependent and independent variables. Results: A total of 325 subjects were included in this study....
In this study, NIMROD simulations are performed to investigate the effects of massive Helium gas ... more In this study, NIMROD simulations are performed to investigate the effects of massive Helium gas injection level on the induced disruption on EAST tokamak. It is demonstrated in simulations that two different scenarios of plasma cooling (complete cooling and partial cooling) take place for different amounts of injected impurities. For the impurity injection above a critical level, a single MHD activity is able to induce a complete core temperature collapse. For impurity injection below the critical level, a series of multiple minor disruptions occur before the complete thermal quench (TQ).
2018 IEEE 21st International Multi-Topic Conference (INMIC), 2018
Hybrid power generation system not only reduces our dependency on fossil fuel power generation st... more Hybrid power generation system not only reduces our dependency on fossil fuel power generation stations but also helps us to meet the peak load demand. Renewable energy resources such as solar and wind in hybrid power generation system can play a vital role in reducing fuel cost and emission of conventional power generation system. In this paper, energy scheduling of hybrid power generation system is carried out by considering the fuel cost of thermal power generators and their emissions. Different optimization techniques, genetic algorithm, pattern search method, and interior point algorithm are used in this paper to optimally schedule the energy required from the thermal power generators to meet the load demand by taking into account the power from the renewable energy resources. These optimization techniques are compared in respect of fuel cost, emissions and computational time complexity. Interior point algorithm outperforms patter search method and genetic algorithm. It achieves more reduced fuel cost and emission as compared to pattern search method and genetic algorithm.
YouTube is the second most popular website in the world and is increasingly being used as a platf... more YouTube is the second most popular website in the world and is increasingly being used as a platform for disseminating health information. Our aim was to evaluate the content-quality and audience engagement of YouTube videos pertaining to the SARS (severe acute respiratory syndrome)-CoV-2 virus which causes the Coronavirus Disease 2019 (COVID-19), during the early phase of the pandemic. We chose the first 30 videos for seven different search phrases: "2019 nCoV," "SARS CoV-2," "COVID-19 virus," "coronavirus treatment," "coronavirus explained," "what is the coronavirus" and "coronavirus information." Video contents were evaluated by two independent medical students with more than 5 years of experience using the DISCERN instrument. Qualitative data, quantitative data and upload source for each video was noted for a quality and audience engagement analysis. Out of the total 210 videos, 137 met our inclusion criteria and were evaluated. The mean DISCERN score was 31.33 out of 75 possible points, which indicates that the quality of YouTube videos on COVID-19 is currently poor. There was excellent reliability between the two raters (intraclass correlation coefficient = 0.96). 55% of the videos discussed prevention, 49% discussed symptoms and 46% discussed the spread of the virus. Most of the videos were uploaded by news channels (50%) and education channels (40%). The quality of YouTube videos on SARS-CoV-2 and COVID-19 is poor, however, we have listed the top-quality videos in our article as they may be effective tools for patient education during the pandemic.
Progress in Computational Fluid Dynamics, An International Journal, 2019
In the present study, buoyancy driven flows of water and air in very high aspect ratio (12-48) ho... more In the present study, buoyancy driven flows of water and air in very high aspect ratio (12-48) horizontal rectangular enclosures are studied numerically for Rayleigh numbers ranging from 10 3 to 10 7 using open-source CFD tools to obtain natural convection heat transfer coefficients which are then compared with established empirical correlations based on experimental results. This study has been motivated by the finding that hardly any CFD-based literature on very high aspect ratio rectangular enclosures exist and also by the fact that such enclosures have numerous applications in solar thermal systems such as solar collectors, solar passive heating/cooling systems, and solar stills, etc. It has been reported in the literature that at high aspect ratios, the numerical solution suffers from convergence issues. In the present study, using Code_Saturne as flow solver, the convergence issues have not risen and the error between numerical and experimental results increases with an increase in Rayleigh number bounded by maximum relative error of approximately 8%.
The ability of surfactant aggregate−H 2 O interfaces to control the regioselectivity of Diels−Ald... more The ability of surfactant aggregate−H 2 O interfaces to control the regioselectivity of Diels−Alder reactions has been investigated. Cycloadditions of surfactant 1,3-dienes 2-[[3-(dimethyldodecylsilyl )-1,3-butadien-2-yl]thio]-N,N,N-trimethyl-1-ethanaminium iodide (1a) and 6-[[3-( ...
... John ~ oolcock &amp;#x27; and Abdullah Zafar Indiana University of Pennsylvania Indiana, ... more ... John ~ oolcock &amp;#x27; and Abdullah Zafar Indiana University of Pennsylvania Indiana, PA 15705 ... mass in grams; C is the balance calibration constant; R is the digital display reading when the filled sample tube is in place; R, is the digital display reading for the empty sam-ple tube; x ...
The complex NiBr 2 (2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2) (1) was prepared... more The complex NiBr 2 (2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2) (1) was prepared from the ligand 2-C 12 H 25 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 12 H 25-2 (3) and NiBr 2. Paramagnetic 1 was characterized by combustion analyses, 1 H and 13 C NMR spectroscopy, Vis-NIR spectroscopy, measurement of its magnetic susceptibility, and single-crystal X-ray diffraction. The crystal structure of 1 features octahedral coordination of Ni(II) with axial bromides and fully extended interdigitated alkyl chains. There are significant differences between the solid state structures of 1 and NiBr 2 (2-C 6 H 12 SC 6 H 4 CH NCH 2 CH 2 N CHC 6 H 4 SC 6 H 12-2) (2), a previously reported homologue.
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