Background: The physiological and biochemical demands of intense exercise elicit both muscle-based and systemic responses. The main adaptations to endurance exercise include the correction of electrolyte imbalance, a ...Background: The physiological and biochemical demands of intense exercise elicit both muscle-based and systemic responses. The main adaptations to endurance exercise include the correction of electrolyte imbalance, a decrease in glycogen storage and the increase of oxidative stress, intestinal permeability, muscle damage, and systemic inflammatory response. Adaptations to exercise might be influenced by the gut microbiota, which plays an important role in the production, storage, and expenditure of energy obtained from the diet as well as in inflammation,redox reactions, and hydration status.Methods: A systematic and comprehensive search of electronic databases, including MEDLINE, Scopus, Clinical Trials.gov, Science Direct,Springer Link, and EMBASE was done. The search process was completed using the keywords: "endurance", "exercise", "immune response","microbiota", "nutrition", and "probiotics".Results: Reviewed literature supports the hypothesis that intestinal microbiota might be able to provide a measureable, effective marker of an athlete's immune function and that microbial composition analysis might also be sensitive enough to detect exercise-induced stress and metabolic disorders. The review also supports the hypothesis that modifying the microbiota through the use of probiotics could be an important therapeutic tool to improve athletes' overall general health, performance, and energy availability while controlling inflammation and redox levels.Conclusion: The present review provides a comprehensive overview of how gut microbiota may have a key role in controlling the oxidative stress and inflammatory responses as well as improving metabolism and energy expenditure during intense exercise.展开更多
The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings ...The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neu- rotrophic factor （BDNF） as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery （pBDNF） （i.e., blood serum, blood plasma）, making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise--pBDNF--cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNE For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship： 1） Assessments of cognitive performance may benefit from a focus on various types of memory （e.g., relational, spatial, long-term）; 2） More finegrained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein （i.e., immature, mature）; 3） Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences.展开更多
Background：People experiencing strong feelings of fatigue during exercise sometimes subconsciously yell to refocus their efforts and,thus,maintain exercise performance.The present study examined the influenc of yelli...Background：People experiencing strong feelings of fatigue during exercise sometimes subconsciously yell to refocus their efforts and,thus,maintain exercise performance.The present study examined the influenc of yelling during high-intensity exercise by analysing cardiorespiratory reactions and integrated electromyography（i EMG） changes in the vastus lateralis during a cycle ergometer test.Methods：A total of 23 moderately trained people were recruited.The cycling test began with a resistance of 25 W/min,which was gradually increased.During the experimental trial,the participants were required to yell at least 3 times when they felt exhausted;during the controlled trial,they were not allowed to produce any yelling sounds.The testing order was randomly assigned and the 2 trials were completed within an interval between 3–10 days.Two-way repeated measures ANOVA was applied to analyse the differences within and between the trials,and interaction of trial and time.Results：The peak power and time to exhaustion（p〈0.01） in the yelling trial were higher than those in the control trial.However,the vastus lateralis iE MG values of both trials at peak power were not significant y different.During the yelling period at 90%–100% of the maximal effort,a significan time-by-trialinteraction（p〈0.05）wasobservedinoxygenconsumption（VO2）,CO2 production,O2 pulse,ventilation,andrespiratoryrate. Alltheabove measures showed a significan between-trial difference（p〈0.02）.However,heart rate,respiratory exchange ratio,end-tidal oxygen pressure,and ventilatory equivalent for oxygen showed only significan between-trial difference（p〈0.05）,but without interaction of trial and time.Conclusion：Yelling enhances the peak O2 pulse and VO2 and maintains CO2-exclusion efficien y during high-intensity exercise.It may enable maintaining muscle activation without stronger EMG signals being required during high-intensity exercise.展开更多
Semisolid billet of AZ80 magnesium alloy was prepared by new strain induced melt activated (new SIMA) process and thixoforging experiment was performed.The results show that after as-cast AZ80 magnesium alloy is proce...Semisolid billet of AZ80 magnesium alloy was prepared by new strain induced melt activated (new SIMA) process and thixoforging experiment was performed.The results show that after as-cast AZ80 magnesium alloy is processed by equal channel angular extrusion, microstructure is refined well due to heavy dynamic recrystallization occurring in severe plastic deformation.Compared with semisolid isothermal treatment and conventional SIMA, semisolid billet with fine and spheroidal grains are achieved in new SIMA.Thixoforging process of semisolid billet prepared by new SIMA has many advantages such as good surface quality of final component, high ability to fill cavity and net-shape.The fine and spheroidal grains and high mechanical properties such as tensile strength of 298 MPa and elongation of 28% can be developed in final part thixoforged.展开更多
＂Verbatim＂ is a kind of documentary theatre in which drama is made from the precise words spoken by people in evidence, witnessing or remembering. Raising political issues and controversial topics, My Name Is Rachel...＂Verbatim＂ is a kind of documentary theatre in which drama is made from the precise words spoken by people in evidence, witnessing or remembering. Raising political issues and controversial topics, My Name Is Rachel Corrie （2005） is not just a moving play about violence in the Palestinian conflict. It is the real story of the murder of an American activist＇s fighting to denounce the genocide of innocent people. The problems of censorship that the play suffered in his premiere in New York remark the voice of a controversial play in Broadway＇s world. This paper will examine the images of violence present in the play and the value of the speaker as a real witness展开更多
Born of the America of 1960s, performance art comes along as a celebration of presentation rather than re-presentation, as a display form of art, and an art form that does not admit of duplication. This paper presents...Born of the America of 1960s, performance art comes along as a celebration of presentation rather than re-presentation, as a display form of art, and an art form that does not admit of duplication. This paper presents a reading of the seductive power of performance art as rooted in our theatrical nature. I will address performance art as an emancipated form of the theatrical, where by ＂theatrical＂ I mean a specific mode of presentation and a specific mode of perception： the mode of presentation of the self to the social and the mode of perception of the self through the social. Performance art, I will argue, is hardly an anomaly of our time. Rather, its source of disturbance and fascination lies in the natural, though excessive manifestation of our theatrical nature. By its appeal to the shocking, the perilous, or the mundane even, this form of art confirms what Paul Woodruff has addressed as ＂the necessity of watching and being watched.＂ Performance art shows us the danger of self-presentation, the recognition of the other gaze as the self＇s greatest need and greatest fear. It needs no words. Mere action is more seductive than speech and does not accept speech in return. Once it has been performed, it is no longer. In Nietzsche＇s words, it celebrates the fleeting moment＇s ＂greatest weight.＂ As Samuel Beckett used to tell his actors, performance artists seem to tell their spectators： ＂Go on failing. Go on. Only next time, try to fail better.＂展开更多
Recently,the newly booming metal halide perovskites have attracted extensive attention worldwide due to their outstanding optoelectronic performance,and are expected to be ideal candidates for photodetectors(PDs).Howe...Recently,the newly booming metal halide perovskites have attracted extensive attention worldwide due to their outstanding optoelectronic performance,and are expected to be ideal candidates for photodetectors(PDs).However,there is still lack of perovskite PDs-based imaging devices coming into commercialization stage,due to some practical reasons including toxicity brought by lead-based perovskites and the large light current fluctuations.In this paper,for the first time we fabricate a lead-free Cs3Bi2Br9 perovskite PD,and build a prototype of this perovskite PD-based imaging system with diffuse reflection imaging mode.Moreover,we propose a new parameter F related to light current fluctuation to evaluate imaging performance of a PD especially for weak diffuse light condition,and prove its usability by comparison of unoptimized lead-free Cs3Bi2Br9 perovskite PD and atomic layer deposition(ALD)optimized Cs3Bi2 Br9 PD.ALD-optimization can improve the quality of perovskite film and suppress the dark current and current fluctuation.Finally,we obtain satisfactory diffuse reflection images of 2D and 3D objects with wide dynamic range.Therefore,the ALD-optimized Cs3Bi2Br9PD has addressed two major concerns about perovskite PDs-based imaging devices,that may extend application of perovskite materials and improve imaging quality.展开更多
文摘Background: The physiological and biochemical demands of intense exercise elicit both muscle-based and systemic responses. The main adaptations to endurance exercise include the correction of electrolyte imbalance, a decrease in glycogen storage and the increase of oxidative stress, intestinal permeability, muscle damage, and systemic inflammatory response. Adaptations to exercise might be influenced by the gut microbiota, which plays an important role in the production, storage, and expenditure of energy obtained from the diet as well as in inflammation,redox reactions, and hydration status.Methods: A systematic and comprehensive search of electronic databases, including MEDLINE, Scopus, Clinical Trials.gov, Science Direct,Springer Link, and EMBASE was done. The search process was completed using the keywords: "endurance", "exercise", "immune response","microbiota", "nutrition", and "probiotics".Results: Reviewed literature supports the hypothesis that intestinal microbiota might be able to provide a measureable, effective marker of an athlete's immune function and that microbial composition analysis might also be sensitive enough to detect exercise-induced stress and metabolic disorders. The review also supports the hypothesis that modifying the microbiota through the use of probiotics could be an important therapeutic tool to improve athletes' overall general health, performance, and energy availability while controlling inflammation and redox levels.Conclusion: The present review provides a comprehensive overview of how gut microbiota may have a key role in controlling the oxidative stress and inflammatory responses as well as improving metabolism and energy expenditure during intense exercise.
文摘The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neu- rotrophic factor （BDNF） as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery （pBDNF） （i.e., blood serum, blood plasma）, making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise--pBDNF--cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNE For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship： 1） Assessments of cognitive performance may benefit from a focus on various types of memory （e.g., relational, spatial, long-term）; 2） More finegrained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein （i.e., immature, mature）; 3） Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences.
基金supported by a Grant-in-Aid for Scientifi Research (ISU99-04-03) from I-Shou University,Kaohsiung,Taiwan,China
文摘Background：People experiencing strong feelings of fatigue during exercise sometimes subconsciously yell to refocus their efforts and,thus,maintain exercise performance.The present study examined the influenc of yelling during high-intensity exercise by analysing cardiorespiratory reactions and integrated electromyography（i EMG） changes in the vastus lateralis during a cycle ergometer test.Methods：A total of 23 moderately trained people were recruited.The cycling test began with a resistance of 25 W/min,which was gradually increased.During the experimental trial,the participants were required to yell at least 3 times when they felt exhausted;during the controlled trial,they were not allowed to produce any yelling sounds.The testing order was randomly assigned and the 2 trials were completed within an interval between 3–10 days.Two-way repeated measures ANOVA was applied to analyse the differences within and between the trials,and interaction of trial and time.Results：The peak power and time to exhaustion（p〈0.01） in the yelling trial were higher than those in the control trial.However,the vastus lateralis iE MG values of both trials at peak power were not significant y different.During the yelling period at 90%–100% of the maximal effort,a significan time-by-trialinteraction（p〈0.05）wasobservedinoxygenconsumption（VO2）,CO2 production,O2 pulse,ventilation,andrespiratoryrate. Alltheabove measures showed a significan between-trial difference（p〈0.02）.However,heart rate,respiratory exchange ratio,end-tidal oxygen pressure,and ventilatory equivalent for oxygen showed only significan between-trial difference（p〈0.05）,but without interaction of trial and time.Conclusion：Yelling enhances the peak O2 pulse and VO2 and maintains CO2-exclusion efficien y during high-intensity exercise.It may enable maintaining muscle activation without stronger EMG signals being required during high-intensity exercise.
基金Project(50605015) supported by the National Natural Science Foundation of ChinaProject(HITQNJS.2008.012) supported by Development Program for Outstanding Young Teachers in Harbin Institute of Technology,China+1 种基金Projects(20090460884,20080440849) supported by China Postdoctoral Science FoundationProject(LBH-Q08104) supported by the Postdoctoral Foundation of Heilongjiang Province,China
文摘Semisolid billet of AZ80 magnesium alloy was prepared by new strain induced melt activated (new SIMA) process and thixoforging experiment was performed.The results show that after as-cast AZ80 magnesium alloy is processed by equal channel angular extrusion, microstructure is refined well due to heavy dynamic recrystallization occurring in severe plastic deformation.Compared with semisolid isothermal treatment and conventional SIMA, semisolid billet with fine and spheroidal grains are achieved in new SIMA.Thixoforging process of semisolid billet prepared by new SIMA has many advantages such as good surface quality of final component, high ability to fill cavity and net-shape.The fine and spheroidal grains and high mechanical properties such as tensile strength of 298 MPa and elongation of 28% can be developed in final part thixoforged.
文摘＂Verbatim＂ is a kind of documentary theatre in which drama is made from the precise words spoken by people in evidence, witnessing or remembering. Raising political issues and controversial topics, My Name Is Rachel Corrie （2005） is not just a moving play about violence in the Palestinian conflict. It is the real story of the murder of an American activist＇s fighting to denounce the genocide of innocent people. The problems of censorship that the play suffered in his premiere in New York remark the voice of a controversial play in Broadway＇s world. This paper will examine the images of violence present in the play and the value of the speaker as a real witness
文摘Born of the America of 1960s, performance art comes along as a celebration of presentation rather than re-presentation, as a display form of art, and an art form that does not admit of duplication. This paper presents a reading of the seductive power of performance art as rooted in our theatrical nature. I will address performance art as an emancipated form of the theatrical, where by ＂theatrical＂ I mean a specific mode of presentation and a specific mode of perception： the mode of presentation of the self to the social and the mode of perception of the self through the social. Performance art, I will argue, is hardly an anomaly of our time. Rather, its source of disturbance and fascination lies in the natural, though excessive manifestation of our theatrical nature. By its appeal to the shocking, the perilous, or the mundane even, this form of art confirms what Paul Woodruff has addressed as ＂the necessity of watching and being watched.＂ Performance art shows us the danger of self-presentation, the recognition of the other gaze as the self＇s greatest need and greatest fear. It needs no words. Mere action is more seductive than speech and does not accept speech in return. Once it has been performed, it is no longer. In Nietzsche＇s words, it celebrates the fleeting moment＇s ＂greatest weight.＂ As Samuel Beckett used to tell his actors, performance artists seem to tell their spectators： ＂Go on failing. Go on. Only next time, try to fail better.＂
基金the National Natural Science Foundation of China(61604061,51772135,and 61875074)the Natural Science Foundation of Guangdong Province(2017A020215135,2018A030310659,and 2019A1515010482)+1 种基金the Science and Technology Program of Guangzhou,China(201804010432)the China Postdoctoral Science Foundation(2019M663363)。
文摘Recently,the newly booming metal halide perovskites have attracted extensive attention worldwide due to their outstanding optoelectronic performance,and are expected to be ideal candidates for photodetectors(PDs).However,there is still lack of perovskite PDs-based imaging devices coming into commercialization stage,due to some practical reasons including toxicity brought by lead-based perovskites and the large light current fluctuations.In this paper,for the first time we fabricate a lead-free Cs3Bi2Br9 perovskite PD,and build a prototype of this perovskite PD-based imaging system with diffuse reflection imaging mode.Moreover,we propose a new parameter F related to light current fluctuation to evaluate imaging performance of a PD especially for weak diffuse light condition,and prove its usability by comparison of unoptimized lead-free Cs3Bi2Br9 perovskite PD and atomic layer deposition(ALD)optimized Cs3Bi2 Br9 PD.ALD-optimization can improve the quality of perovskite film and suppress the dark current and current fluctuation.Finally,we obtain satisfactory diffuse reflection images of 2D and 3D objects with wide dynamic range.Therefore,the ALD-optimized Cs3Bi2Br9PD has addressed two major concerns about perovskite PDs-based imaging devices,that may extend application of perovskite materials and improve imaging quality.
