The impacts of O_3 concentration change on rice yields for different lengths of exposure time are studied by means of the OTC-1 open-top chamber.The resuhs indicate that when O_3 concentration increased from 50 ppb to...The impacts of O_3 concentration change on rice yields for different lengths of exposure time are studied by means of the OTC-1 open-top chamber.The resuhs indicate that when O_3 concentration increased from 50 ppb to 200 ppb during the time period of 20 to 80 days in the experiment,the rice yield was reduced by 6.78% to 33.72%.Two main influencing factors for rice yields are the increased O_3 concentration and the extended exposure time.Using a logarithm function to simulate the impacts of O_3 concentration on rice yields is better than using a the Weibull function.展开更多
With the increasing number of people suffering from heart failure,ventricular assist devices have gradually become an effective way to treat end-stage heart failure.However,the blood damage caused by ventricular assis...With the increasing number of people suffering from heart failure,ventricular assist devices have gradually become an effective way to treat end-stage heart failure.However,the blood damage caused by ventricular assist devices has not been effectively solved,which is an obstacle to its clinical promotion.Most research focused on erythrocyte damage under shear stress,while few researches were conducted on the interaction between blood under shear stress and the induction of von Willebrand factor(VWF)damage.This research used a vortex oscillator blood-shearing platform to conduct in vitro experiments and used immunoblotting to quantify VWF damage in sheared samples to study the laws of shear-induced VWF damage under different shear stress,different exposure times,different blood components,and hemolysis conditions.It was found that VWF damage increased with exposure time and shear stress.At the same time,under lower shear stress,other blood components had little effect on VWF damage,while in a higher shear stress,other blood components would accelerate VWF damage.Hemolysis will also affect VWF damage,and the higher the degree of hemolysis,the higher the rate of VWF degradation in the plasma.The results of this research provide a reference for VWF damage evaluation standards and follow-up research and also guide for improving the design of ventricular assist devices to reduce VWF damage.展开更多
The key of the direct method of determining coalbed gas content is how to shorten the coal core exposure time in the sampling progress and reduce measuring error of gas content which comes from the calculation of losi...The key of the direct method of determining coalbed gas content is how to shorten the coal core exposure time in the sampling progress and reduce measuring error of gas content which comes from the calculation of losing gas content. The coring tests were carried out in No.24 drilling field of 715 floor gateway in Qinan Coal Mine by using traditional drill core bar- rel sampler and self-designed reversion seal coring equipment. The losing gas content was calculated by power functional method, and the gas content of two coring methods was determined, respectively. Results show that, compared with traditional drill core barrel sampling, the newly seal coring equipment can significantly shorten the coal core exposure time, the 30 min desorption gas content increases obviously, the calculation of losing gas content reduces by 56.99%, the desorption gas content in normal atmosphere increases by 113.24%, and the determining value of gas content increases by 10.06%. The new technol- ogy has much higher accuracy, and it is worthwhile to be popularized.展开更多
The effects of UV intensity and turbidity on selected microbial indicator inactivation were investigated. Results showed that UV disinfection was effective in killing all the selected microbial indicators, the resista...The effects of UV intensity and turbidity on selected microbial indicator inactivation were investigated. Results showed that UV disinfection was effective in killing all the selected microbial indicators, the resistance order of the microorganisms was as follows： MS-2 coliphage 〉 Bacillus subtilis 〉 E. coil 〉 Staphylococcus aureus and Candida albicans. UV intensity had influence on the inactivation of all the microorganisms, high UV disinfection efficency was obtained with higher UV intensity. Turbidity had impact on the bacteria inactivation rate, but there was no evidence that turbidity had any negative contribution to MS-2 coliphage. Under the same UV dosage, higher UV intensity could overcome the negative influence of turbidity on UV performance, enhanced microorganism inactivation effect in turbidity water.展开更多
Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg s...Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg survival rates per day were highest in the mid intertidal zone(45.1%±25.4%)and the lowest in the low intertidal zone(13.3%±27.6%).Differences in the elevation,air exposure time,and water content of the spawning ground were significant factors determining the egg survival rates.Excessive or insufficient air exposure time resulted in inadequate water content at higher and lower intertidal zones and could reduce egg survival.On the other hand,moderate saturation and dehydration were repeated with each tidal movement in the mid intertidal zone.This dynamic is considered as one of the crucial factors for the survival of eggs and is considered optimal for spawning.Therefore,the protection of the mid intertidal zone is imperative for maximizing the egg survival rate in Tsuyazaki Cove where almost all suitable nesting sites have disappeared due to coastal development.By protecting these optimal sites for spawning and recovering other optimal sites on suitable beaches,a positive contribution can be made to future management and conservation.The study also suggests that translocating eggs from marginal to optimal spawning sites might be a recovery strategy for this globally endangered species.展开更多
In order to analyze the distribution and characterizations of corrosion pits on the corroded surface,the steel surface data was measured. Based on the method of the interacting pits,the types of pits corresponding to ...In order to analyze the distribution and characterizations of corrosion pits on the corroded surface,the steel surface data was measured. Based on the method of the interacting pits,the types of pits corresponding to different exposure time were observed and categorized for completely understanding the effects on the fatigue behavior. The results showed that the conditions for estimating whether the pits interfere with each other should not be ignored; exposure time with 2 years was a critical time. The exposure time and the interacting pits can observably reduce the fatigue life of corroded steel. From these conclusions,the method of fatigue crack growth rate with the multi-pits interaction(FCGR-MPI) was developed and used to predict the fatigue behavior of corroded steel affected with the interacting pits. The predicted lives were also well agreed with the experimental results.展开更多
Objective:To explore the relationship between acid reflux and esophageal motility in patients with gastroesophageal reflux disease.Methods:From January 2018 to December 2019,80 patients with typical gastroesophageal r...Objective:To explore the relationship between acid reflux and esophageal motility in patients with gastroesophageal reflux disease.Methods:From January 2018 to December 2019,80 patients with typical gastroesophageal reflux symptoms such as reflux and heartburn were randomly selected from the Department of Gastroenterology,First Affiliated Hospital of guangxi university of chinese medicine.The patients were divided into pathological group,sensitive group and physiological group based on the percentage of acid exposure time and reflux-symptom correlation.The GerdQ score,quality of life score,esophageal acid test and esophageal manometry related parameters of the three groups of patients were compared.Results:Compared with the sensitive group and the physiological group,the GerdQ score,DeMeester score,orthostatic acid reflux time,orthostatic acid reflux time,longest acid reflux time and acid reflux times in the pathological group were significantly higher.Sf-36 score,lower esophageal sphincter pressure and effective rate of deglutition were all significantly reduced,with statistically significant differences(P<0.05).Compared with the physiological group,the GerdQ score of the sensitive group was higher.The sf-36 score was low,and the differences were statistically significant(P<0.05).The acid indexes in the sensitive group were higher than those in the physiological group,but the differences were not statistically significant(P>0.05).Compared with the physiological group,the distal contraction integral and the amplitude of the lower esophageal sphincter 3cm above the pathological group and the sensitive group decreased significantly(P<0.05).There were no statistically significant differences in the length of the lower esophageal sphincter,the length of the lower esophageal sphincter in the abdominal segment,the amplitude of the upper esophageal sphincter at 7cm and 11cm and the peristaltic wave velocity of the esophageal body in the three groups(P>0.05).Conclusion:the decrease of lower esophageal sphincter pressure is the key factor leading to pathological acid reflux,and acid reflux is closely related to distal contraction integral and peristaltic amplitude of 3cm on lower esophageal sphincter in patients with gastroesophageal reflux disease.展开更多
Roller Compacted Concrete (RCC) has gained favorable recognition in hydropower and water resource dam construction. With optimization in construction technology and materials used for RCC Dams, cost is no longer a maj...Roller Compacted Concrete (RCC) has gained favorable recognition in hydropower and water resource dam construction. With optimization in construction technology and materials used for RCC Dams, cost is no longer a major disadvantage as compared to environmental impact, that is, wildlife habitat disruption. In as much as it has become optimal for investment in hydropower dam construction, the scourge for dam failure is still eminent, which is as a result of excessive seepage compromising the integrity of the mechanical properties of the dam. The aim of the paper is to highlight successful application methods in joint bonding to avoid excessive seepage and reduce the autogenous healing to a few years of operation. In view of optimization, this paper presents a comprehensive study on the influences of interlayer joints bonding quality from RCC mix performances and how it consolidates the RCC layers to withstand the shear strength along the interface, especially on the high dams. The case study is the RCC dam at the 750 MW Kafue Gorge Lower Hydropower Station. The scope of the study reviews the joint type judged by Modified Maturity Factor (MMF) with joint surface long time exposed in regions with dry and high temperature, technical measures of layer bonding quality control under condition of long time joint surface exposure, effects of joints shear strength and impermeability of the RCC layers when under the conditions of plastic and elasticity. The subtle observations made during the dam construction phases were with respect to the optimal use of materials in relation to RCC mix designs and the basis for equipment calibration for monitoring important data that can be referenced during analysis of shear forces acting on the RCC dam over time.展开更多
Pterygium is sunlight related, ocular-surface lesion that obscures vision. The morbidity varies in different parts of the same country. Several surveys have shown that the countries nearer the equator have higher rate...Pterygium is sunlight related, ocular-surface lesion that obscures vision. The morbidity varies in different parts of the same country. Several surveys have shown that the countries nearer the equator have higher rate of pterygium than the other regions, the possible reason is due to the low latitude and stronger exposure to ultraviolet rays. The onset of pterygium is closely related to the environment, including ultraviolet rays, sandstorm, dry climate and so on. Prolonged ultraviolet-B radiation is regarded as a risk factor for pterygium, and that could explain its prevalence is much higher in the low latitude area.展开更多
For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RC...For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RCS statistical uncertainty and the RCS difference with the change of incident angle.Based on the RCS characteristics of typical stealth aircraft,this paper established a simplified RCS dynamic fluctuation statistical model with the parameters log mean and log standard deviation.According to the detection probability algorithm in radar signal processing field,this paper built the algorithm of radar detection probability based on the RCS dynamic fluctuation statistical model.The analysis of examples concluded that the key to successful penetration is to shorten the RCS peak exposure time,which can be reduced by decreasing the RCS peak width or increasing velocity.Based on the conclusion,this paper proposed the method of turning maneuvering to reduce RCS peak exposure time dramatically.展开更多
A controlled hydroponic experiment was undertaken to investigate Cd uptake in relation to the activity of Cd species in solution other than the free ion （Cd^2＋） by maintaining a constant Cd^2＋ activity under varia...A controlled hydroponic experiment was undertaken to investigate Cd uptake in relation to the activity of Cd species in solution other than the free ion （Cd^2＋） by maintaining a constant Cd^2＋ activity under variable SO4^2- and Cl^- concentrations exposed to maize （Zea mays vat. Cameron） plants. The objectives of these experiments were： （1） to distinguish and quantify the different uptake rates of free and inorganic-complexed Cd from nutrient solution, and （2） to model the uptake of Cd by maize with a Biotic Ligand Model （BLM） in a system which facilitates the close examination of root characteristics. Results of the current experiments suggest that, in addition to the free ion, CdSO4^0 complexes are important factors in determining Cd uptake in nutrient solution by maize plants. Higher nominal SO4^2- concentrations in solution generally resulted in a greater Cd accumulation by maize plants than predicted by the Cd^2＋ activity. A better integration of the complete dataset for the 3 harvest times （6, 9 and 11 days after treatment） was achieved by including consideration of both the duration of Cd exposure and especially the root surface area to express Cd uptake. Similarly, the fit of the BLM was also improved when taking into account exposure time and expressing uptake in terms of root morphological parameters.展开更多
基金supported by the Key Project of National Natural Science Foundation of China(49899270)
文摘The impacts of O_3 concentration change on rice yields for different lengths of exposure time are studied by means of the OTC-1 open-top chamber.The resuhs indicate that when O_3 concentration increased from 50 ppb to 200 ppb during the time period of 20 to 80 days in the experiment,the rice yield was reduced by 6.78% to 33.72%.Two main influencing factors for rice yields are the increased O_3 concentration and the extended exposure time.Using a logarithm function to simulate the impacts of O_3 concentration on rice yields is better than using a the Weibull function.
基金supported by 2023 Kunshan Science and Technology Association youth science and technology talent lifting project(Project name:Mechanism study of mechanical damage of coagulation factor VWF based on in vitro blood-shearing experimental platform).
文摘With the increasing number of people suffering from heart failure,ventricular assist devices have gradually become an effective way to treat end-stage heart failure.However,the blood damage caused by ventricular assist devices has not been effectively solved,which is an obstacle to its clinical promotion.Most research focused on erythrocyte damage under shear stress,while few researches were conducted on the interaction between blood under shear stress and the induction of von Willebrand factor(VWF)damage.This research used a vortex oscillator blood-shearing platform to conduct in vitro experiments and used immunoblotting to quantify VWF damage in sheared samples to study the laws of shear-induced VWF damage under different shear stress,different exposure times,different blood components,and hemolysis conditions.It was found that VWF damage increased with exposure time and shear stress.At the same time,under lower shear stress,other blood components had little effect on VWF damage,while in a higher shear stress,other blood components would accelerate VWF damage.Hemolysis will also affect VWF damage,and the higher the degree of hemolysis,the higher the rate of VWF degradation in the plasma.The results of this research provide a reference for VWF damage evaluation standards and follow-up research and also guide for improving the design of ventricular assist devices to reduce VWF damage.
文摘The key of the direct method of determining coalbed gas content is how to shorten the coal core exposure time in the sampling progress and reduce measuring error of gas content which comes from the calculation of losing gas content. The coring tests were carried out in No.24 drilling field of 715 floor gateway in Qinan Coal Mine by using traditional drill core bar- rel sampler and self-designed reversion seal coring equipment. The losing gas content was calculated by power functional method, and the gas content of two coring methods was determined, respectively. Results show that, compared with traditional drill core barrel sampling, the newly seal coring equipment can significantly shorten the coal core exposure time, the 30 min desorption gas content increases obviously, the calculation of losing gas content reduces by 56.99%, the desorption gas content in normal atmosphere increases by 113.24%, and the determining value of gas content increases by 10.06%. The new technol- ogy has much higher accuracy, and it is worthwhile to be popularized.
文摘The effects of UV intensity and turbidity on selected microbial indicator inactivation were investigated. Results showed that UV disinfection was effective in killing all the selected microbial indicators, the resistance order of the microorganisms was as follows： MS-2 coliphage 〉 Bacillus subtilis 〉 E. coil 〉 Staphylococcus aureus and Candida albicans. UV intensity had influence on the inactivation of all the microorganisms, high UV disinfection efficency was obtained with higher UV intensity. Turbidity had impact on the bacteria inactivation rate, but there was no evidence that turbidity had any negative contribution to MS-2 coliphage. Under the same UV dosage, higher UV intensity could overcome the negative influence of turbidity on UV performance, enhanced microorganism inactivation effect in turbidity water.
文摘Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg survival rates per day were highest in the mid intertidal zone(45.1%±25.4%)and the lowest in the low intertidal zone(13.3%±27.6%).Differences in the elevation,air exposure time,and water content of the spawning ground were significant factors determining the egg survival rates.Excessive or insufficient air exposure time resulted in inadequate water content at higher and lower intertidal zones and could reduce egg survival.On the other hand,moderate saturation and dehydration were repeated with each tidal movement in the mid intertidal zone.This dynamic is considered as one of the crucial factors for the survival of eggs and is considered optimal for spawning.Therefore,the protection of the mid intertidal zone is imperative for maximizing the egg survival rate in Tsuyazaki Cove where almost all suitable nesting sites have disappeared due to coastal development.By protecting these optimal sites for spawning and recovering other optimal sites on suitable beaches,a positive contribution can be made to future management and conservation.The study also suggests that translocating eggs from marginal to optimal spawning sites might be a recovery strategy for this globally endangered species.
基金Sponsored by the National Natural Science Foundation of China(Grant No.NSC-51378417 and NSC-51078307)the Dr. Startup Found of Southwest University of Science and Technology(16zx7136)
文摘In order to analyze the distribution and characterizations of corrosion pits on the corroded surface,the steel surface data was measured. Based on the method of the interacting pits,the types of pits corresponding to different exposure time were observed and categorized for completely understanding the effects on the fatigue behavior. The results showed that the conditions for estimating whether the pits interfere with each other should not be ignored; exposure time with 2 years was a critical time. The exposure time and the interacting pits can observably reduce the fatigue life of corroded steel. From these conclusions,the method of fatigue crack growth rate with the multi-pits interaction(FCGR-MPI) was developed and used to predict the fatigue behavior of corroded steel affected with the interacting pits. The predicted lives were also well agreed with the experimental results.
基金Medical Scientific Research Fund(No.YWJKJKHKYJJ-A308)
文摘Objective:To explore the relationship between acid reflux and esophageal motility in patients with gastroesophageal reflux disease.Methods:From January 2018 to December 2019,80 patients with typical gastroesophageal reflux symptoms such as reflux and heartburn were randomly selected from the Department of Gastroenterology,First Affiliated Hospital of guangxi university of chinese medicine.The patients were divided into pathological group,sensitive group and physiological group based on the percentage of acid exposure time and reflux-symptom correlation.The GerdQ score,quality of life score,esophageal acid test and esophageal manometry related parameters of the three groups of patients were compared.Results:Compared with the sensitive group and the physiological group,the GerdQ score,DeMeester score,orthostatic acid reflux time,orthostatic acid reflux time,longest acid reflux time and acid reflux times in the pathological group were significantly higher.Sf-36 score,lower esophageal sphincter pressure and effective rate of deglutition were all significantly reduced,with statistically significant differences(P<0.05).Compared with the physiological group,the GerdQ score of the sensitive group was higher.The sf-36 score was low,and the differences were statistically significant(P<0.05).The acid indexes in the sensitive group were higher than those in the physiological group,but the differences were not statistically significant(P>0.05).Compared with the physiological group,the distal contraction integral and the amplitude of the lower esophageal sphincter 3cm above the pathological group and the sensitive group decreased significantly(P<0.05).There were no statistically significant differences in the length of the lower esophageal sphincter,the length of the lower esophageal sphincter in the abdominal segment,the amplitude of the upper esophageal sphincter at 7cm and 11cm and the peristaltic wave velocity of the esophageal body in the three groups(P>0.05).Conclusion:the decrease of lower esophageal sphincter pressure is the key factor leading to pathological acid reflux,and acid reflux is closely related to distal contraction integral and peristaltic amplitude of 3cm on lower esophageal sphincter in patients with gastroesophageal reflux disease.
文摘Roller Compacted Concrete (RCC) has gained favorable recognition in hydropower and water resource dam construction. With optimization in construction technology and materials used for RCC Dams, cost is no longer a major disadvantage as compared to environmental impact, that is, wildlife habitat disruption. In as much as it has become optimal for investment in hydropower dam construction, the scourge for dam failure is still eminent, which is as a result of excessive seepage compromising the integrity of the mechanical properties of the dam. The aim of the paper is to highlight successful application methods in joint bonding to avoid excessive seepage and reduce the autogenous healing to a few years of operation. In view of optimization, this paper presents a comprehensive study on the influences of interlayer joints bonding quality from RCC mix performances and how it consolidates the RCC layers to withstand the shear strength along the interface, especially on the high dams. The case study is the RCC dam at the 750 MW Kafue Gorge Lower Hydropower Station. The scope of the study reviews the joint type judged by Modified Maturity Factor (MMF) with joint surface long time exposed in regions with dry and high temperature, technical measures of layer bonding quality control under condition of long time joint surface exposure, effects of joints shear strength and impermeability of the RCC layers when under the conditions of plastic and elasticity. The subtle observations made during the dam construction phases were with respect to the optimal use of materials in relation to RCC mix designs and the basis for equipment calibration for monitoring important data that can be referenced during analysis of shear forces acting on the RCC dam over time.
基金This sdudy was supported by grants from National Natural Science Foundation of China (No. 40275036) the Project of High School Science Research of Department of Education in Liaoning Province (No. 2004C026).
文摘Pterygium is sunlight related, ocular-surface lesion that obscures vision. The morbidity varies in different parts of the same country. Several surveys have shown that the countries nearer the equator have higher rate of pterygium than the other regions, the possible reason is due to the low latitude and stronger exposure to ultraviolet rays. The onset of pterygium is closely related to the environment, including ultraviolet rays, sandstorm, dry climate and so on. Prolonged ultraviolet-B radiation is regarded as a risk factor for pterygium, and that could explain its prevalence is much higher in the low latitude area.
文摘For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RCS statistical uncertainty and the RCS difference with the change of incident angle.Based on the RCS characteristics of typical stealth aircraft,this paper established a simplified RCS dynamic fluctuation statistical model with the parameters log mean and log standard deviation.According to the detection probability algorithm in radar signal processing field,this paper built the algorithm of radar detection probability based on the RCS dynamic fluctuation statistical model.The analysis of examples concluded that the key to successful penetration is to shorten the RCS peak exposure time,which can be reduced by decreasing the RCS peak width or increasing velocity.Based on the conclusion,this paper proposed the method of turning maneuvering to reduce RCS peak exposure time dramatically.
基金supported by the Severn Trent Water Ltd. as co-funders of the Biorem 11 (PASS) Project under the Bioremediation Link Programme (UK BBSRC)the financia support from CONACYT,Mexico (No. 137972)
文摘A controlled hydroponic experiment was undertaken to investigate Cd uptake in relation to the activity of Cd species in solution other than the free ion （Cd^2＋） by maintaining a constant Cd^2＋ activity under variable SO4^2- and Cl^- concentrations exposed to maize （Zea mays vat. Cameron） plants. The objectives of these experiments were： （1） to distinguish and quantify the different uptake rates of free and inorganic-complexed Cd from nutrient solution, and （2） to model the uptake of Cd by maize with a Biotic Ligand Model （BLM） in a system which facilitates the close examination of root characteristics. Results of the current experiments suggest that, in addition to the free ion, CdSO4^0 complexes are important factors in determining Cd uptake in nutrient solution by maize plants. Higher nominal SO4^2- concentrations in solution generally resulted in a greater Cd accumulation by maize plants than predicted by the Cd^2＋ activity. A better integration of the complete dataset for the 3 harvest times （6, 9 and 11 days after treatment） was achieved by including consideration of both the duration of Cd exposure and especially the root surface area to express Cd uptake. Similarly, the fit of the BLM was also improved when taking into account exposure time and expressing uptake in terms of root morphological parameters.
