Spatial optimization as part of spatial modeling has been facilitated significantly by integration with GIS techniques. However, for certain research topics, applying standard GIS techniques may create problems which ...Spatial optimization as part of spatial modeling has been facilitated significantly by integration with GIS techniques. However, for certain research topics, applying standard GIS techniques may create problems which require attention. This paper serves as a cautionary note to demonstrate two problems associated with applying GIS in spatial optimization, using a capacitated p-median facility location optimization problem as an example. The first problem involves errors in interpolating spatial variations of travel costs from using kriging, a common set of techniques for raster files. The second problem is inaccuracy in routing performed on a graph directly created from polyline shapefiles, a common vector file type. While revealing these problems, the paper also suggests remedies. Specifically, interpolation errors can be eliminated by using agent-based spatial modeling while the inaccuracy in routing can be improved through altering the graph topology by splitting the long edges of the shapefile. These issues suggest the need for caution in applying GIS in spatial optimization study.展开更多
Vehicular speeds are of particular interest in areas with a high number of pedestrians due to the fact that 14-percent of all fatal crashes involve pedestrians. This study investigated the effect of a radar speed disp...Vehicular speeds are of particular interest in areas with a high number of pedestrians due to the fact that 14-percent of all fatal crashes involve pedestrians. This study investigated the effect of a radar speed display sign placed for an extended period of time, at a location frequented by law enforcement on a road segment entering a university campus with a high number of pedestrians and vehicle speed violations. The statistical analysis included a comparison between AM peak, PM peak, and midday speeds collected one year apart. The data suggested that radar speed display signs can remain effective over a long period of time;causing drivers to decelerate when warned of a speeding violation. While other studies have examined long-term impacts of similar technologies, none have included a road entering a University campus. Thus, these findings support that other similar locations entering university campuses could see long-term benefits to stationary radar speed display signs.展开更多
Purpose: The relationship between acute exercise and executive functions in college students with attention deficit hyperactivity disorder (ADHD) has not been clearly established. The purpose of this preliminary st...Purpose: The relationship between acute exercise and executive functions in college students with attention deficit hyperactivity disorder (ADHD) has not been clearly established. The purpose of this preliminary study was to examine the difference in cognitive performance between college students with and without ADHD and to explore the effects of acute exercise on multiple aspects of executive functions and on serum brain derived neurotrophic factor (BDNF). Methods: College students (normal: n = 10; ADHD: n = 10) performed the Stroop Test, Trail Making Test, and Digit Span Test prior to and after an acute exercise intervention. Blood samples were obtained prior to the pre-test cognitive test performance and then again after exercise and prior to the post-test cognitive test performance. Results: Students with ADHD exhibited impaired executive functions, particularly on inhibition. Additionally, while acute exercise improved all aspects of executive functions in those without ADHD, acute exercise only improved inhibitory performance for those with ADHD. Further, BDNF was not influenced by acute exercise regardless of the subjects' ADHD status. Conclusion: These results provide preliminary evidence for exercise as a potential adjunct treatment for benefitting inhibition in college students with ADHD.展开更多
Background: Anecdotally, parents often report that children with attention deficit hyperactivity disorder (ADHD) who engage in regular physical activity (PA) experience positive behavioral changes. The purpose of...Background: Anecdotally, parents often report that children with attention deficit hyperactivity disorder (ADHD) who engage in regular physical activity (PA) experience positive behavioral changes. The purpose of this study was to examine this anecdotal relationship to provide preliminary evidence relevant to the potential benefits of PA on ADHD symptoms. Methods: Parents (n = 68) of children diagnosed with ADHD completed an lnternet survey assessing perceptions of how PA influences their child's symptoms. Results: A significantly greater percentage of parents reported that regular PA positively impacted symptoms. However, there were no uniform effects for all types of ADHD symptoms. The results indicate that there may be more positive benefits for symptoms of inattention and hyperactivity than for those of impulsivity. Conclusion: This is the first study to empirically document parents' perceptions of how PA influences ADHD and suggests that PA can be a viable strategy for reducing symptoms. PA may have greater benefits for specific symptoms of ADHD, providing critical information for developing PA interventions for children and adolescents.展开更多
AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participan...AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participants were eligible patients attending an outpatient nephrology clinic. Participants were administered: Newest Vital Sign to measure HL, CKD self-managementknowledge tool(CKD-SMKT) to assess knowledge, past performance of CKD-SMB, CKD-A. Estimated GFR(e GFR) was determined using the MDRD-4 equation. Duration of clinic participation and CKD cause were extracted from medical charts. RESULTS One-hundred-fifty patients participated in the study. e GFRs ranged from 17-152 m L/min per 1.73 m2. Majority(83%) of respondents had stage 3 or 4 CKD, low HL(63%), and were CKD aware(88%). Approximately 40%(10/25) of patients in stages 1 and 2 and 6.4%(8/125) in stages 3 and 4 were unaware of their CKD. CKD-A differed with stage(P < 0.001) but not by HL level, duration of clinic participation, or CKD cause. Majority of respondents(≥ 90%) correctly answered one or more CKD-SMKT items. Knowledge of one behavior, "controlling blood pressure" differed significantly by CKD-A. CKD-A was associated with past performance of two CKD-SMBs, "controlling blood pressure"(P = 0.02), and "keeping healthy body weight"(P = 0.01). Adjusted multivariate analyses between CKD-A and:(1) HL; and(2) CKD-SMB knowledge were nonsignificant. However, there was a significant relationship between CKD-A and kidney function after controlling for demographics, HL, and CKD-SMB(P < 0.05). CONCLUSION CKD-A is not associated with HL, or better CKD-SMBs. CKD-A is significantly associated with kidney function and substantially lower e GFR, suggesting the need for focused patient education in CKD stages 1.展开更多
In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well kn...In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known <em>factorization method</em>, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a <em>mixed reciprocity principle</em>, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called <em>Improved Maximum Product Criterion</em> (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no <em>a priori</em> knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples.展开更多
This article explains an imagery assisted virtual reality psychological skills training program used with a NCAA Division I baseball team. This is the first time that imagery has been incorporated into a virtual reali...This article explains an imagery assisted virtual reality psychological skills training program used with a NCAA Division I baseball team. This is the first time that imagery has been incorporated into a virtual reality program with the goal of increasing mental skills and strategies. Participants for this study were 27 NCAA baseball players. Each participant completed the Sport Imagery Ability Questionnaire and the Test of Performance Strategies Questionnaire at baseline and again after the winter season (2 months later). Results indicated an increase in skill, goals and mastery imagery ability as well as increases in the use of several skills and strategies in both practice and competition. This manuscript focuses on both the development of an Imagery Assisted Virtual Reality program as well as the outcomes of the program.展开更多
Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to eval...Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to evaluate functions of reservoirs′ locations and magnitudes on daily peak flow attenuation for a large basin of China, namely Ganjiang River Basin. In this study, the Xinanjiang model was adopted to simulate inflows of the reservoirs and flood hydrographs of all sub-catchments of the basin, and simple reservoir operation rules were established for calculating outflows of the reservoirs. Four reservoirs scenarios were established to analyze reservoirs′ locations on daily peak flow attenuation. The results showed that: 1) reservoirs attenuated the peak discharges for all simulated floods, when the flood storage capacities increase as new reservoirs were built, the peak discharge attenuation by reservoirs showed an increasing tendency both in absolute and relative measures; 2) reservoirs attenuated more peak discharge relatively for small floods than for large ones; 3) reservoirs reduced the peak discharge more efficiently for the floods with single peak or multi peaks with main peak occurred first; and 4) effect of upstream reservoirs on peak attenuation decreased from upper reaches to lower reaches; upstream and midstream reservoirs played important roles in decreasing peak discharge both at middle and lower reaches, and downstream reservoirs had less effect on large peak discharge attenuation at outlet of the basin. The proposed framework of evaluating functions of multiple reservoirs′ storage capacities and locations on peak attenuation is valuable for flood control planning and management at basin scale.展开更多
We present a theoretical analysis for heat transfer in power law non-Newtonian fluid by assuming that the thermal diffusivity is a function of temperature gradient. The laminar boundary layer energy equation is consid...We present a theoretical analysis for heat transfer in power law non-Newtonian fluid by assuming that the thermal diffusivity is a function of temperature gradient. The laminar boundary layer energy equation is considered as an example to illustrate the application. It is shown that the boundary layer energy equation subject to the corresponding boundary conditions can be transformed to a boundary value problem of a nonlinear ordinary differential equation when similarity variables are introduced. Numerical solutions of the similarity energy equation are presented.展开更多
The benefits of running for cardiovascular health have long been established, but no relationship between runners/non-runners and their usage of prescription and over-the-counter (OTC) medications has been established...The benefits of running for cardiovascular health have long been established, but no relationship between runners/non-runners and their usage of prescription and over-the-counter (OTC) medications has been established. A comprehensive survey was sent out via Facebook, Inc., to self-identified runners to assess runners’ first response to 5 common self-care situations. The results were compared to the national average of the U.S. population who take prescription and OTC medications. What was also assessed was the relationship between average weekly miles run and the likelihood to choose OTC medications. 714 runners, residing predominately in the St. Louis, Missouri metropolitan area, completed the survey and their results were drastically different than the national average use for prescription and OTC medication in the general (non-runners) population. Approximately 30% of the runners in this study are on daily prescription medications versus a national average of 70% of the U.S. population. In each of the 5 common self-care situations, less than 50% of runners chose an OTC medication as their first option for self-care vs. the national average of 80%. Results of the study also showed that runners with a weekly mile average of 30 miles or more were less likely to choose an OTC option for self-care than runners with a weekly average of 15 miles or less. Overall, results of this survey suggest that runners are less likely to take medications and may be healthier than the average U.S. citizen overall.展开更多
Objectives: 1) To demonstrate that education outreach in public schools by students in pharmacy education programs is effective at increasing knowledge of important health topics;2) To assess subject attitude towards ...Objectives: 1) To demonstrate that education outreach in public schools by students in pharmacy education programs is effective at increasing knowledge of important health topics;2) To assess subject attitude towards pharmacy careers after education outreach. Study: A lecture was constructed providing participants with information about careers in pharmacy, diabetes, and information about health literacy. A multiple choice paper-based quiz covering the presented content both preceded and followed each delivery of the lecture. Increases in post-lecture scores of content-knowledge questions were seen in 10 of 11 questions, which indicated an overall increased knowledge from baseline. An additional question, which gauged student interest in pharmacy careers, showed a 10% increase in those who indicated they considered pharmacy as a career. Conclusions: The lectures, delivered by a student pharmacist, were effective in increasing awareness and knowledge of pharmacy as a career, diabetes as an important health issue, and health literacy as a problem pharmacists and other healthcare providers encounter on a daily basis.展开更多
This paper investigates the evolution of the role of the first lady of the United States, which is of particular interest because of its non-constitutional and non-formal nature that has become one of the most promine...This paper investigates the evolution of the role of the first lady of the United States, which is of particular interest because of its non-constitutional and non-formal nature that has become one of the most prominent and visible non-paid positions in the world. The first lady's responsibility has evolved from serving as a social hostess and a ceremonial presence at the side of the President, to serving as a spokeswoman for the country. More recently, in addition to her other duties, the first lady has acted as a political surrogate for the President. This study conducts a social movement rhetorical analysis, using the technique of discourse tracing, to examine how and why the culture of the office of the first lady has evolved. Finally, this study will add current political culture scholarship by investigating issues surrounding the 2016 presidential election.展开更多
A series of novel catalysts was developed using cationic Gemini surfactants intercalated in natural montmorillonite (MMT) clay. These Gemini surfactant-MMT intercalates were used to study the kinetics of a nucleophili...A series of novel catalysts was developed using cationic Gemini surfactants intercalated in natural montmorillonite (MMT) clay. These Gemini surfactant-MMT intercalates were used to study the kinetics of a nucleophilic displacement reactions converting n-butyl bromide to n-butyl chloride in a triphase catalytic (TC) system. Most reaction rates compared favorably to those of biphase catalytic reactions where Gemini surfactants were used in the absence of MMT. Catalytic activity varied with Gemini surfactant structure, specifically with carbon spacer group and side chain length. In addition to the ease of catalyst separation that a triphase system affords, Gemini-MMT catalysts are stable and can be recycled and re-used several times.展开更多
This study uses a spatial 3-stage least squares approach to model interstate banking of the United States in 1994 and 2014.The method simultaneously takes into account spatial dependence,outward and inward interstate ...This study uses a spatial 3-stage least squares approach to model interstate banking of the United States in 1994 and 2014.The method simultaneously takes into account spatial dependence,outward and inward interstate banking and their interaction,and the temporal effects in interstate banking.The study shows that a healthy economic structure,an expanding market,and permissive banking legislation encourage inward interstate banking.A healthy economic structure is a basis for strong banking firms to rise and to expand in other states.Large banking institutions were dominate in outward interstate banking while smaller firm sizes tend to be associated with inward interstate banking.By 2014,large and well-capitalized banking firms from states with a healthy economic structure had expanded into states with lower income levels,and lower capital-to-labor ratios,higher labor resource use,and lower profitability in their banking industry.Evidence shows some banking geographical fragmentation remains.展开更多
A remarkable rate enhancement technique has been devised for a typical nucleophilic displacement reaction by using triphase catalytic materials based on tetraoctylammonium exchange forms of hectorite clay. Pseudo-firs...A remarkable rate enhancement technique has been devised for a typical nucleophilic displacement reaction by using triphase catalytic materials based on tetraoctylammonium exchange forms of hectorite clay. Pseudo-first order rate constants (kobs) for the conversion of 1-bromobutane to the corresponding chloride under triphase conditions using the clay catalyst in the presence of various polar cosolvents have been observed. The results here have shown that the addition of a cosolvent increases the catalytic activity of the triphase system by several fold. In addition, the results have demonstrated that each cosolvent has a unique concentration for achieving an optimum reaction rate.展开更多
The safety impact of changes to roadway operations have been of interests in recent years with the publication of the Highway Safety Manual.One area that is in need of further study is the safety impact of traffic sig...The safety impact of changes to roadway operations have been of interests in recent years with the publication of the Highway Safety Manual.One area that is in need of further study is the safety impact of traffic signal coordination projects in urban areas.Specifically,this study seeks to identify the safety benefit from traffic signal coordination projects on major arterial roadways through urban areas using a before and after study with a comparison groups approach and a meta-analysis method.The findings suggest that traffic signal coordination could decrease total crashes by 21 percent,injury crashes by 52 percent and property-damage-only crashes by 21 percent.The results can be utilized by engineering practitioners to estimate the safety benefits for projects that seek to coordinate traffic signals along an urban corridor.Because these projects can both improve the safety of roadways while improving traffic flow,the application of these findings could be broad.展开更多
Acid Yellow 25 (AY25) is used in the textile industry for dyeing of natural and synthetic fibers, and is also used as a coloring agent in paints, inks, plastics, and leathers. Effluents from such industries are major ...Acid Yellow 25 (AY25) is used in the textile industry for dyeing of natural and synthetic fibers, and is also used as a coloring agent in paints, inks, plastics, and leathers. Effluents from such industries are major sources of water pollution. Hence, it is important to find simple, efficient, and inexpensive ways to remove these dyes from wastewater. Here, we determined the suitability of chitin extracted from waste crab legs as an adsorbent for removing AY25 dye. The adsorption kinetics was modeled using pseudo-first order, pseudo-second order, and intraparticle diffusion equations to determine the rate controlling step. Results showed that the pseudo-second order adsorption mechanism is predominant, and the overall rate of the dye adsorption process is therefore controlled by an adsorption reaction. Adsorption isotherms were analyzed by utilizing the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models at 23℃, with data collected by using various initial dye concentrations with different chitin dosages. Our results show the highest correlation with the Langmuir model, consistent with the fact that chitin contains both a monolayer and homogeneous adsorption sites. Based on the D-R model, the adsorption of AY25 dye onto chitin is via chemisorption. Furthermore, we have concluded that the rate constants of both pseudo-second order adsorption and film diffusion are correlated to the initial dye concentrations and chitin dosages. In conclusion, chitin from waste crab legs is a very suitable adsorbent material that is capable of rapidly removing up to 95% of the initial concentration of AY25 dye at a pH of 2 and room temperature.展开更多
文摘Spatial optimization as part of spatial modeling has been facilitated significantly by integration with GIS techniques. However, for certain research topics, applying standard GIS techniques may create problems which require attention. This paper serves as a cautionary note to demonstrate two problems associated with applying GIS in spatial optimization, using a capacitated p-median facility location optimization problem as an example. The first problem involves errors in interpolating spatial variations of travel costs from using kriging, a common set of techniques for raster files. The second problem is inaccuracy in routing performed on a graph directly created from polyline shapefiles, a common vector file type. While revealing these problems, the paper also suggests remedies. Specifically, interpolation errors can be eliminated by using agent-based spatial modeling while the inaccuracy in routing can be improved through altering the graph topology by splitting the long edges of the shapefile. These issues suggest the need for caution in applying GIS in spatial optimization study.
文摘Vehicular speeds are of particular interest in areas with a high number of pedestrians due to the fact that 14-percent of all fatal crashes involve pedestrians. This study investigated the effect of a radar speed display sign placed for an extended period of time, at a location frequented by law enforcement on a road segment entering a university campus with a high number of pedestrians and vehicle speed violations. The statistical analysis included a comparison between AM peak, PM peak, and midday speeds collected one year apart. The data suggested that radar speed display signs can remain effective over a long period of time;causing drivers to decelerate when warned of a speeding violation. While other studies have examined long-term impacts of similar technologies, none have included a road entering a University campus. Thus, these findings support that other similar locations entering university campuses could see long-term benefits to stationary radar speed display signs.
文摘Purpose: The relationship between acute exercise and executive functions in college students with attention deficit hyperactivity disorder (ADHD) has not been clearly established. The purpose of this preliminary study was to examine the difference in cognitive performance between college students with and without ADHD and to explore the effects of acute exercise on multiple aspects of executive functions and on serum brain derived neurotrophic factor (BDNF). Methods: College students (normal: n = 10; ADHD: n = 10) performed the Stroop Test, Trail Making Test, and Digit Span Test prior to and after an acute exercise intervention. Blood samples were obtained prior to the pre-test cognitive test performance and then again after exercise and prior to the post-test cognitive test performance. Results: Students with ADHD exhibited impaired executive functions, particularly on inhibition. Additionally, while acute exercise improved all aspects of executive functions in those without ADHD, acute exercise only improved inhibitory performance for those with ADHD. Further, BDNF was not influenced by acute exercise regardless of the subjects' ADHD status. Conclusion: These results provide preliminary evidence for exercise as a potential adjunct treatment for benefitting inhibition in college students with ADHD.
文摘Background: Anecdotally, parents often report that children with attention deficit hyperactivity disorder (ADHD) who engage in regular physical activity (PA) experience positive behavioral changes. The purpose of this study was to examine this anecdotal relationship to provide preliminary evidence relevant to the potential benefits of PA on ADHD symptoms. Methods: Parents (n = 68) of children diagnosed with ADHD completed an lnternet survey assessing perceptions of how PA influences their child's symptoms. Results: A significantly greater percentage of parents reported that regular PA positively impacted symptoms. However, there were no uniform effects for all types of ADHD symptoms. The results indicate that there may be more positive benefits for symptoms of inattention and hyperactivity than for those of impulsivity. Conclusion: This is the first study to empirically document parents' perceptions of how PA influences ADHD and suggests that PA can be a viable strategy for reducing symptoms. PA may have greater benefits for specific symptoms of ADHD, providing critical information for developing PA interventions for children and adolescents.
文摘AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participants were eligible patients attending an outpatient nephrology clinic. Participants were administered: Newest Vital Sign to measure HL, CKD self-managementknowledge tool(CKD-SMKT) to assess knowledge, past performance of CKD-SMB, CKD-A. Estimated GFR(e GFR) was determined using the MDRD-4 equation. Duration of clinic participation and CKD cause were extracted from medical charts. RESULTS One-hundred-fifty patients participated in the study. e GFRs ranged from 17-152 m L/min per 1.73 m2. Majority(83%) of respondents had stage 3 or 4 CKD, low HL(63%), and were CKD aware(88%). Approximately 40%(10/25) of patients in stages 1 and 2 and 6.4%(8/125) in stages 3 and 4 were unaware of their CKD. CKD-A differed with stage(P < 0.001) but not by HL level, duration of clinic participation, or CKD cause. Majority of respondents(≥ 90%) correctly answered one or more CKD-SMKT items. Knowledge of one behavior, "controlling blood pressure" differed significantly by CKD-A. CKD-A was associated with past performance of two CKD-SMBs, "controlling blood pressure"(P = 0.02), and "keeping healthy body weight"(P = 0.01). Adjusted multivariate analyses between CKD-A and:(1) HL; and(2) CKD-SMB knowledge were nonsignificant. However, there was a significant relationship between CKD-A and kidney function after controlling for demographics, HL, and CKD-SMB(P < 0.05). CONCLUSION CKD-A is not associated with HL, or better CKD-SMBs. CKD-A is significantly associated with kidney function and substantially lower e GFR, suggesting the need for focused patient education in CKD stages 1.
文摘In this paper, we consider the numerical treatment of an inverse acoustic scattering problem that involves an impenetrable obstacle embedded in a layered medium. We begin by employing a modified version of the well known <em>factorization method</em>, in which a computationally effective numerical scheme for the reconstruction of the shape of the scatterer is presented. This is possible, due to a <em>mixed reciprocity principle</em>, which renders the computation of the Green function at the background medium unnecessary. Moreover, to further refine our inversion algorithm, an efficient Tikhonov parameter choice technique, called <em>Improved Maximum Product Criterion</em> (IMPC) is exploited. Our regularization parameter is computed via a fast iterative algorithm which requires no <em>a priori</em> knowledge of the noise level in the far-field data. Finally, the effectiveness of IMPC is illustrated with various numerical examples.
文摘This article explains an imagery assisted virtual reality psychological skills training program used with a NCAA Division I baseball team. This is the first time that imagery has been incorporated into a virtual reality program with the goal of increasing mental skills and strategies. Participants for this study were 27 NCAA baseball players. Each participant completed the Sport Imagery Ability Questionnaire and the Test of Performance Strategies Questionnaire at baseline and again after the winter season (2 months later). Results indicated an increase in skill, goals and mastery imagery ability as well as increases in the use of several skills and strategies in both practice and competition. This manuscript focuses on both the development of an Imagery Assisted Virtual Reality program as well as the outcomes of the program.
基金Commonwealth and Specialized Programs for Scientific Research,Ministry of Water Resources of China(No.200901042)
文摘Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to evaluate functions of reservoirs′ locations and magnitudes on daily peak flow attenuation for a large basin of China, namely Ganjiang River Basin. In this study, the Xinanjiang model was adopted to simulate inflows of the reservoirs and flood hydrographs of all sub-catchments of the basin, and simple reservoir operation rules were established for calculating outflows of the reservoirs. Four reservoirs scenarios were established to analyze reservoirs′ locations on daily peak flow attenuation. The results showed that: 1) reservoirs attenuated the peak discharges for all simulated floods, when the flood storage capacities increase as new reservoirs were built, the peak discharge attenuation by reservoirs showed an increasing tendency both in absolute and relative measures; 2) reservoirs attenuated more peak discharge relatively for small floods than for large ones; 3) reservoirs reduced the peak discharge more efficiently for the floods with single peak or multi peaks with main peak occurred first; and 4) effect of upstream reservoirs on peak attenuation decreased from upper reaches to lower reaches; upstream and midstream reservoirs played important roles in decreasing peak discharge both at middle and lower reaches, and downstream reservoirs had less effect on large peak discharge attenuation at outlet of the basin. The proposed framework of evaluating functions of multiple reservoirs′ storage capacities and locations on peak attenuation is valuable for flood control planning and management at basin scale.
基金Supported by the National Natural Science Foundations of China under Grant No 50476083.
文摘We present a theoretical analysis for heat transfer in power law non-Newtonian fluid by assuming that the thermal diffusivity is a function of temperature gradient. The laminar boundary layer energy equation is considered as an example to illustrate the application. It is shown that the boundary layer energy equation subject to the corresponding boundary conditions can be transformed to a boundary value problem of a nonlinear ordinary differential equation when similarity variables are introduced. Numerical solutions of the similarity energy equation are presented.
文摘The benefits of running for cardiovascular health have long been established, but no relationship between runners/non-runners and their usage of prescription and over-the-counter (OTC) medications has been established. A comprehensive survey was sent out via Facebook, Inc., to self-identified runners to assess runners’ first response to 5 common self-care situations. The results were compared to the national average of the U.S. population who take prescription and OTC medications. What was also assessed was the relationship between average weekly miles run and the likelihood to choose OTC medications. 714 runners, residing predominately in the St. Louis, Missouri metropolitan area, completed the survey and their results were drastically different than the national average use for prescription and OTC medication in the general (non-runners) population. Approximately 30% of the runners in this study are on daily prescription medications versus a national average of 70% of the U.S. population. In each of the 5 common self-care situations, less than 50% of runners chose an OTC medication as their first option for self-care vs. the national average of 80%. Results of the study also showed that runners with a weekly mile average of 30 miles or more were less likely to choose an OTC option for self-care than runners with a weekly average of 15 miles or less. Overall, results of this survey suggest that runners are less likely to take medications and may be healthier than the average U.S. citizen overall.
文摘Objectives: 1) To demonstrate that education outreach in public schools by students in pharmacy education programs is effective at increasing knowledge of important health topics;2) To assess subject attitude towards pharmacy careers after education outreach. Study: A lecture was constructed providing participants with information about careers in pharmacy, diabetes, and information about health literacy. A multiple choice paper-based quiz covering the presented content both preceded and followed each delivery of the lecture. Increases in post-lecture scores of content-knowledge questions were seen in 10 of 11 questions, which indicated an overall increased knowledge from baseline. An additional question, which gauged student interest in pharmacy careers, showed a 10% increase in those who indicated they considered pharmacy as a career. Conclusions: The lectures, delivered by a student pharmacist, were effective in increasing awareness and knowledge of pharmacy as a career, diabetes as an important health issue, and health literacy as a problem pharmacists and other healthcare providers encounter on a daily basis.
文摘This paper investigates the evolution of the role of the first lady of the United States, which is of particular interest because of its non-constitutional and non-formal nature that has become one of the most prominent and visible non-paid positions in the world. The first lady's responsibility has evolved from serving as a social hostess and a ceremonial presence at the side of the President, to serving as a spokeswoman for the country. More recently, in addition to her other duties, the first lady has acted as a political surrogate for the President. This study conducts a social movement rhetorical analysis, using the technique of discourse tracing, to examine how and why the culture of the office of the first lady has evolved. Finally, this study will add current political culture scholarship by investigating issues surrounding the 2016 presidential election.
文摘A series of novel catalysts was developed using cationic Gemini surfactants intercalated in natural montmorillonite (MMT) clay. These Gemini surfactant-MMT intercalates were used to study the kinetics of a nucleophilic displacement reactions converting n-butyl bromide to n-butyl chloride in a triphase catalytic (TC) system. Most reaction rates compared favorably to those of biphase catalytic reactions where Gemini surfactants were used in the absence of MMT. Catalytic activity varied with Gemini surfactant structure, specifically with carbon spacer group and side chain length. In addition to the ease of catalyst separation that a triphase system affords, Gemini-MMT catalysts are stable and can be recycled and re-used several times.
文摘This study uses a spatial 3-stage least squares approach to model interstate banking of the United States in 1994 and 2014.The method simultaneously takes into account spatial dependence,outward and inward interstate banking and their interaction,and the temporal effects in interstate banking.The study shows that a healthy economic structure,an expanding market,and permissive banking legislation encourage inward interstate banking.A healthy economic structure is a basis for strong banking firms to rise and to expand in other states.Large banking institutions were dominate in outward interstate banking while smaller firm sizes tend to be associated with inward interstate banking.By 2014,large and well-capitalized banking firms from states with a healthy economic structure had expanded into states with lower income levels,and lower capital-to-labor ratios,higher labor resource use,and lower profitability in their banking industry.Evidence shows some banking geographical fragmentation remains.
文摘A remarkable rate enhancement technique has been devised for a typical nucleophilic displacement reaction by using triphase catalytic materials based on tetraoctylammonium exchange forms of hectorite clay. Pseudo-first order rate constants (kobs) for the conversion of 1-bromobutane to the corresponding chloride under triphase conditions using the clay catalyst in the presence of various polar cosolvents have been observed. The results here have shown that the addition of a cosolvent increases the catalytic activity of the triphase system by several fold. In addition, the results have demonstrated that each cosolvent has a unique concentration for achieving an optimum reaction rate.
文摘The safety impact of changes to roadway operations have been of interests in recent years with the publication of the Highway Safety Manual.One area that is in need of further study is the safety impact of traffic signal coordination projects in urban areas.Specifically,this study seeks to identify the safety benefit from traffic signal coordination projects on major arterial roadways through urban areas using a before and after study with a comparison groups approach and a meta-analysis method.The findings suggest that traffic signal coordination could decrease total crashes by 21 percent,injury crashes by 52 percent and property-damage-only crashes by 21 percent.The results can be utilized by engineering practitioners to estimate the safety benefits for projects that seek to coordinate traffic signals along an urban corridor.Because these projects can both improve the safety of roadways while improving traffic flow,the application of these findings could be broad.
文摘Acid Yellow 25 (AY25) is used in the textile industry for dyeing of natural and synthetic fibers, and is also used as a coloring agent in paints, inks, plastics, and leathers. Effluents from such industries are major sources of water pollution. Hence, it is important to find simple, efficient, and inexpensive ways to remove these dyes from wastewater. Here, we determined the suitability of chitin extracted from waste crab legs as an adsorbent for removing AY25 dye. The adsorption kinetics was modeled using pseudo-first order, pseudo-second order, and intraparticle diffusion equations to determine the rate controlling step. Results showed that the pseudo-second order adsorption mechanism is predominant, and the overall rate of the dye adsorption process is therefore controlled by an adsorption reaction. Adsorption isotherms were analyzed by utilizing the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models at 23℃, with data collected by using various initial dye concentrations with different chitin dosages. Our results show the highest correlation with the Langmuir model, consistent with the fact that chitin contains both a monolayer and homogeneous adsorption sites. Based on the D-R model, the adsorption of AY25 dye onto chitin is via chemisorption. Furthermore, we have concluded that the rate constants of both pseudo-second order adsorption and film diffusion are correlated to the initial dye concentrations and chitin dosages. In conclusion, chitin from waste crab legs is a very suitable adsorbent material that is capable of rapidly removing up to 95% of the initial concentration of AY25 dye at a pH of 2 and room temperature.