Water transport time lag in the Soil-Plant-Atmosphere Continuum(SPAC)significantly impacts ecosystem hydrology and plant water relations,yet the relative contributions of different segments(soil vs.plant)to the total ...Water transport time lag in the Soil-Plant-Atmosphere Continuum(SPAC)significantly impacts ecosystem hydrology and plant water relations,yet the relative contributions of different segments(soil vs.plant)to the total lag and their response mechanisms under drought remain unclear.This study aimed to quantitatively partition the total SPAC water transport time lag through controlled experiments,identify the dominant component driving the drought response,and compare coexisting tree species with contrasting hydraulic strategies:Platycladus orientalis and Quercus variabilis.We conducted potted plant isotope(δ^(2)H)labeling experiments under normal water and drought stress treatments for both species.Using high-frequency isotope sampling and synchronous sap flow monitoring,we quantified the total water transport time lag from the soil surface to canopy branches(T_(iso),based on initial isotope arrival)and the internal plant transport time lag(T_(sap),based on sap flow path integration).An independent laboratory soil mixing experiment determined the baseline soil mixing time lag(T_(mix)),and the lag associated with soil infiltration and root uptake initiation was estimated(T_(soil)=T_(iso)−T_(sap)).The physical mixing of old and new soil water introduced a baseline time lag(T_(mix))of approximately 8-12 h.Under normal water conditions,the internal plant lag(T_(sap):37-40 h)constituted the major part of the total lag(T_(iso):43-46 h),with the estimated soil process lag(T_(soil))being relatively short(3-9 h).Drought stress significantly prolonged the total time lag.Crucially,this increase was primarily driven by a dramatic increase in the internal plant transport time lag(T_(sap)):T_(sap) increased by 77 h(193%)for P.orientalis and 33 h(89%)for Q.variabilis.In contrast,the estimated soil process lag(T_(soil))showed minimal increase(or even decreased)under drought.Consequently,the increase in T_(sap) almost entirely accounted for the prolongation of T_(iso)(T_(iso) increased by 188%for P.orientalis and 63%for Q.variabilis).Furthermore,the shallow-rooted P.orientalis was more sensitive to drought in terms of internal time lag increase compared to the deep-rooted Q.variabilis.Our direct experimental evidence demonstrates that internal plant physiological and hydraulic processes,rather than soil processes,dominantly regulate the response of total SPAC water transport time lag to drought stress.Tree species with different hydraulic strategies exhibit distinct time lag response mechanisms.These findings challenge traditional perspectives potentially overemphasizing soil limitations and highlight the critical importance of understanding internal plant dynamics for accurately predicting the temporal responses of ecosystem water relations.展开更多
The objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to 11 hours, and two sp...The objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to 11 hours, and two space allowances (2 m2 and 1.5 m2 per animal for cows and bulls; and 1.2 m2 and 0.8 m2 per animal for calves) were used for the experiment during transport from farms to the abattoir in Uppsala, Sweden. Measurements were made on five animals on each trip. Stress response parameters considered were cortisol, glucose, lactate, creatine kinase and heart rate. Blood samples were taken before and after transport. Heart rate sensors were mounted on the animals at least 30 minutes before loading and measurements were made continuously from farms to the abattoirs until stunning. The results of heart rate measurement indicated that loading, un-loading and forced movement in the stunning box were the most stressful events. However, the results of statistical analysis confirmed that transport time doesn't have significant effect (P 〈 0.05) on heart rate. Concentration level of cortisol increased by 10 folds during short transport. However, cortisol concentration decreased with an increase of transport times (P 〈 0.01). Glucose concentrations increased with transport time in all animal categories (P ≤ 0.01). Transport time has significant effect on concentration levels of glucose (P ≤ 0.01), creatine kinase (P 〈 0.001) and lactate (P 〈 0.01) particularly after 6 hours journey time.展开更多
Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality...Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality. Limited data exist on the influence of transport time on patient outcomes with specific injury types. The objective of this study was to determine the impact of the duration of time from the initial request for medical evacuation to arrival at a medical treatment facility on morbidity and mortality in casualties with traumatic extremity amputation and noncompressible torso injury(NCTI).Methods: We completed a retrospective review of MEDEVAC patient care records for United States military personnel who sustained traumatic amputations and NCTI during Operation Enduring Freedom between January 2011 and March 2014. We grouped patients as traumatic amputation and NCTI(AMP+NCTI), traumatic amputation only(AMP),and neither AMP nor NCTI(Non-AMP/NCTI). Analysis was performed using chi-squared tests, Fisher's exact tests,Cochran-Armitage Trend tests, Shapiro-Wilks tests, Wilcoxon and Kruskal-Wallis techniques and Cox proportional hazards regression modeling.Results: We reviewed 1267 records, of which 669 had an injury severity score(ISS) of 10 or greater and were included in the analysis. In the study population, 15.5% sustained only amputation injuries(n=104, AMP only), 10.8% sustained amputation and NCTI(n=72, AMP+NCTI), and 73.7% did not sustain either an amputation or an NCTI(n=493,Non-AMP/NCTI). AMP+NCTI had the highest mortality(16.7%) with transport time greater than 60 min. While the AMP+NCTI group had decreasing survival with longer transport times, AMP and Non-AMP/NCTI did not exhibit the same trend.Conclusions: A decreased transport time from the point of injury to a medical treatment facility was associated with decreased mortality in patients who suffered a combination of amputation injury and NCTI. No significant association between transport time and outcomes was found in patients who did not sustain NCTI. Priority for rapid evacuation of combat casualties should be given to those with NCTI.展开更多
Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The resul...Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The results show that wagon transfer time is the most critical factor among the three subjective factors of wagons turnover time. The FISM based analysis of wagon transfer time show that the wagon turnover time is significantly correlated with transit time with resorting. Among the seven factors of detention time of transit time with resorting, the time of waiting to departing, converging, and waiting to break-up are key factors, while the time of make-up, break-up, arrival and departure are general factors. We carried out one empirical research based on the data of Baoji East Railway Station in 2015. The results of empirical research and FISM are consistent completely.展开更多
Minimization of transportation time is a great concern of the transportation problems like the cost minimizing transportation problems. In this writing, a transportation algorithm is developed and applied to obtain an...Minimization of transportation time is a great concern of the transportation problems like the cost minimizing transportation problems. In this writing, a transportation algorithm is developed and applied to obtain an Initial Basic Feasible Solution (IBFS) of transportation problems in minimizing transportation time. The developed method has also been illustrated numerically to test the efficiency of the method where it is observed that the proposed method yields a better result.展开更多
Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dyna...Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dynamic structures of proteins at the interfaces with suffi- cient structural and temporal resolutions. Here, we demonstrate that a ferntosecond sum frequency generation vibrational spectroscopy (SFG-VS) system developed by our group provides a powerful tool for monitoring the real-tirne peptide transport across the membranes with time resolution of less than one second. By probing the real-time SFG signals in the arnide I and arnide A bands as WALP23 interacts with DMPG lipid bilayer, it is found that WALP23 is initially absorbed at the gel-phase DMPG bilayer with a random coil structure. The absorption of WALP23 on the surface leads to the surface charge reversal and thus changes the orientation of rnembrane-bound water. As the DMPG bilayer changes from gel phase into fluid phase, WALP23 inserts into the fluid-phase bilayer with its N-terminal end moving across the membrane, which causes the membrane dehydration and the transition of WALP23 conformation from random coil to mixed helix/loop structure and then to pure α-helical structure. The established system is ready to be employed in characterizing other interracial fast processes, which will be certainly helpful for providing a clear physical picture of the interracial phenomena.展开更多
Jumping from place to place, replicating food, biological or mechanical parts or beaming up somebody, may not be fiction, rather an issue of practical implementation as shall be observed in this paper. Devices like tr...Jumping from place to place, replicating food, biological or mechanical parts or beaming up somebody, may not be fiction, rather an issue of practical implementation as shall be observed in this paper. Devices like transporter, food replicators or warp drive intrigue our imagination. This paper is intended to show that Jump drive is an issue of coordinate transformation. Changing location from planet X to planet Y does not necessarily require travelling a distance D connecting between the two planets. The theoretical knowledge of changing the location from coordinate X to coordinate Y exists;we do that in signal processing, but, we have not yet developed such a machine. The present paper shows the feasibility of jump drive;however, much work needs to be done on the implementation.展开更多
Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 ...Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 emissions.Therefore,the CO2 emission reduction of the transport sector is of great importance.In order to reduce emissions effectively,it is necessary to change the distribution and transportation processes.The purpose of this study is to minimize both the transportation costs and CO2 emissions during transportation.Our model considers a transportation scheduling problem in which loads are transported from an overseas production base to three domestic demand centers.The need for time-space networks arises naturally to improve the model.It is possible to know the distance carriers are moving,and also consider the timetables of carriers during transportation.Carrier choice,less-than carrier load,and domestic transportation among demand centers are considered as the three target areas to reduce CO2 emissions during the distribution process.The research model was formulated as a mixed integer programming (MIP) problem.It achieves cost reduction,and will contribute to improvement of the natural environment.展开更多
A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL)...A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL) and real-time passenger information system, key just-in-time (JIT) concepts can now be realized in process design and coordinated scheduling to shape a seamless multimodal transit system. JIT refers to a production system that times both movements of goods during production and delivery from suppliers together. It meets the same logic for seamless multimodal services. Therefore, this study innovatively analyzes possible public transportation technologies for JIT uses;moreover, to layout the possible application frame-work of a transportation technology based JIT multimodal transit system for main station area in Taipei city. With this innovative framework, multimodal transit services can deliver to the right place at right time.展开更多
The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detr...The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detritus has developed unique sedimentary systems in the ECS during the Quaternary, offering ideal terrestrial archives for reconstructing Quaternary paleoenvironmental changes and studying land-sea interactions. Overall, two characteristic river systems dominate the sedimentary systems and sediment source to sink transport patterns in the ECS, represented by the Changjiang(Yangtze River) and Huanghe(Yellow River) for the large river system and Taiwan rivers for the small river system. Given this, the sediments derived from both river systems bear distinct features in terms of parent rock lithology, provenance weathering and sediment transport. Previous studies mostly focus on either the ‘source' discrimination or the ‘sink' records of the sedimentary system in the ECS, while the source to sink process linking the land and sea, in particular its time scale, has been poorly understood. Here we introduce a newly-developed dating technique, the ‘comminution age' method, which offers a quantitative constraint on the time scale of sediment transfer from its ultimate source to the final depositional sink. This novel method is of great significance for improving our understanding on the earth surface processes including tectonic-climate driven weathering, and sediment recycling in relation to landscape evolution and marine environmental changes. The application of comminution age method in the ECS will provide important constraints on sediment source-to-sink process and more evidences for the construction of late Quaternary paleoenvironmental changes under these unique sedimentary systems.展开更多
基金financial supports from the National Science Foundation of China(42277062,41977149 and 42230714).
文摘Water transport time lag in the Soil-Plant-Atmosphere Continuum(SPAC)significantly impacts ecosystem hydrology and plant water relations,yet the relative contributions of different segments(soil vs.plant)to the total lag and their response mechanisms under drought remain unclear.This study aimed to quantitatively partition the total SPAC water transport time lag through controlled experiments,identify the dominant component driving the drought response,and compare coexisting tree species with contrasting hydraulic strategies:Platycladus orientalis and Quercus variabilis.We conducted potted plant isotope(δ^(2)H)labeling experiments under normal water and drought stress treatments for both species.Using high-frequency isotope sampling and synchronous sap flow monitoring,we quantified the total water transport time lag from the soil surface to canopy branches(T_(iso),based on initial isotope arrival)and the internal plant transport time lag(T_(sap),based on sap flow path integration).An independent laboratory soil mixing experiment determined the baseline soil mixing time lag(T_(mix)),and the lag associated with soil infiltration and root uptake initiation was estimated(T_(soil)=T_(iso)−T_(sap)).The physical mixing of old and new soil water introduced a baseline time lag(T_(mix))of approximately 8-12 h.Under normal water conditions,the internal plant lag(T_(sap):37-40 h)constituted the major part of the total lag(T_(iso):43-46 h),with the estimated soil process lag(T_(soil))being relatively short(3-9 h).Drought stress significantly prolonged the total time lag.Crucially,this increase was primarily driven by a dramatic increase in the internal plant transport time lag(T_(sap)):T_(sap) increased by 77 h(193%)for P.orientalis and 33 h(89%)for Q.variabilis.In contrast,the estimated soil process lag(T_(soil))showed minimal increase(or even decreased)under drought.Consequently,the increase in T_(sap) almost entirely accounted for the prolongation of T_(iso)(T_(iso) increased by 188%for P.orientalis and 63%for Q.variabilis).Furthermore,the shallow-rooted P.orientalis was more sensitive to drought in terms of internal time lag increase compared to the deep-rooted Q.variabilis.Our direct experimental evidence demonstrates that internal plant physiological and hydraulic processes,rather than soil processes,dominantly regulate the response of total SPAC water transport time lag to drought stress.Tree species with different hydraulic strategies exhibit distinct time lag response mechanisms.These findings challenge traditional perspectives potentially overemphasizing soil limitations and highlight the critical importance of understanding internal plant dynamics for accurately predicting the temporal responses of ecosystem water relations.
文摘The objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to 11 hours, and two space allowances (2 m2 and 1.5 m2 per animal for cows and bulls; and 1.2 m2 and 0.8 m2 per animal for calves) were used for the experiment during transport from farms to the abattoir in Uppsala, Sweden. Measurements were made on five animals on each trip. Stress response parameters considered were cortisol, glucose, lactate, creatine kinase and heart rate. Blood samples were taken before and after transport. Heart rate sensors were mounted on the animals at least 30 minutes before loading and measurements were made continuously from farms to the abattoirs until stunning. The results of heart rate measurement indicated that loading, un-loading and forced movement in the stunning box were the most stressful events. However, the results of statistical analysis confirmed that transport time doesn't have significant effect (P 〈 0.05) on heart rate. Concentration level of cortisol increased by 10 folds during short transport. However, cortisol concentration decreased with an increase of transport times (P 〈 0.01). Glucose concentrations increased with transport time in all animal categories (P ≤ 0.01). Transport time has significant effect on concentration levels of glucose (P ≤ 0.01), creatine kinase (P 〈 0.001) and lactate (P 〈 0.01) particularly after 6 hours journey time.
基金Department of Defense Joint Program Committee(JPC-6)
文摘Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality. Limited data exist on the influence of transport time on patient outcomes with specific injury types. The objective of this study was to determine the impact of the duration of time from the initial request for medical evacuation to arrival at a medical treatment facility on morbidity and mortality in casualties with traumatic extremity amputation and noncompressible torso injury(NCTI).Methods: We completed a retrospective review of MEDEVAC patient care records for United States military personnel who sustained traumatic amputations and NCTI during Operation Enduring Freedom between January 2011 and March 2014. We grouped patients as traumatic amputation and NCTI(AMP+NCTI), traumatic amputation only(AMP),and neither AMP nor NCTI(Non-AMP/NCTI). Analysis was performed using chi-squared tests, Fisher's exact tests,Cochran-Armitage Trend tests, Shapiro-Wilks tests, Wilcoxon and Kruskal-Wallis techniques and Cox proportional hazards regression modeling.Results: We reviewed 1267 records, of which 669 had an injury severity score(ISS) of 10 or greater and were included in the analysis. In the study population, 15.5% sustained only amputation injuries(n=104, AMP only), 10.8% sustained amputation and NCTI(n=72, AMP+NCTI), and 73.7% did not sustain either an amputation or an NCTI(n=493,Non-AMP/NCTI). AMP+NCTI had the highest mortality(16.7%) with transport time greater than 60 min. While the AMP+NCTI group had decreasing survival with longer transport times, AMP and Non-AMP/NCTI did not exhibit the same trend.Conclusions: A decreased transport time from the point of injury to a medical treatment facility was associated with decreased mortality in patients who suffered a combination of amputation injury and NCTI. No significant association between transport time and outcomes was found in patients who did not sustain NCTI. Priority for rapid evacuation of combat casualties should be given to those with NCTI.
基金Funded by the Fundamental Research Funds for the Central Universities of China(No.26816WTD23)the National United Engineering Laboratory of Integrated and Intelligent Transportation of Southwest Jiaotong University,P.R.China(No.2682017ZT11)
文摘Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The results show that wagon transfer time is the most critical factor among the three subjective factors of wagons turnover time. The FISM based analysis of wagon transfer time show that the wagon turnover time is significantly correlated with transit time with resorting. Among the seven factors of detention time of transit time with resorting, the time of waiting to departing, converging, and waiting to break-up are key factors, while the time of make-up, break-up, arrival and departure are general factors. We carried out one empirical research based on the data of Baoji East Railway Station in 2015. The results of empirical research and FISM are consistent completely.
文摘Minimization of transportation time is a great concern of the transportation problems like the cost minimizing transportation problems. In this writing, a transportation algorithm is developed and applied to obtain an Initial Basic Feasible Solution (IBFS) of transportation problems in minimizing transportation time. The developed method has also been illustrated numerically to test the efficiency of the method where it is observed that the proposed method yields a better result.
基金supported by the National Natural Science Foundation of China(No.21473177,No.21633007)the National Key Research and Development Program of China(No.2017YFA0303500 and No.2018YFA0208700)+1 种基金Fundamental Research Funds for the Central Universities(No.WK2340000064)Anhui Initiative in Quantum Information Technologies(No.AHY090000)
文摘Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dynamic structures of proteins at the interfaces with suffi- cient structural and temporal resolutions. Here, we demonstrate that a ferntosecond sum frequency generation vibrational spectroscopy (SFG-VS) system developed by our group provides a powerful tool for monitoring the real-tirne peptide transport across the membranes with time resolution of less than one second. By probing the real-time SFG signals in the arnide I and arnide A bands as WALP23 interacts with DMPG lipid bilayer, it is found that WALP23 is initially absorbed at the gel-phase DMPG bilayer with a random coil structure. The absorption of WALP23 on the surface leads to the surface charge reversal and thus changes the orientation of rnembrane-bound water. As the DMPG bilayer changes from gel phase into fluid phase, WALP23 inserts into the fluid-phase bilayer with its N-terminal end moving across the membrane, which causes the membrane dehydration and the transition of WALP23 conformation from random coil to mixed helix/loop structure and then to pure α-helical structure. The established system is ready to be employed in characterizing other interracial fast processes, which will be certainly helpful for providing a clear physical picture of the interracial phenomena.
文摘Jumping from place to place, replicating food, biological or mechanical parts or beaming up somebody, may not be fiction, rather an issue of practical implementation as shall be observed in this paper. Devices like transporter, food replicators or warp drive intrigue our imagination. This paper is intended to show that Jump drive is an issue of coordinate transformation. Changing location from planet X to planet Y does not necessarily require travelling a distance D connecting between the two planets. The theoretical knowledge of changing the location from coordinate X to coordinate Y exists;we do that in signal processing, but, we have not yet developed such a machine. The present paper shows the feasibility of jump drive;however, much work needs to be done on the implementation.
文摘Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 emissions.Therefore,the CO2 emission reduction of the transport sector is of great importance.In order to reduce emissions effectively,it is necessary to change the distribution and transportation processes.The purpose of this study is to minimize both the transportation costs and CO2 emissions during transportation.Our model considers a transportation scheduling problem in which loads are transported from an overseas production base to three domestic demand centers.The need for time-space networks arises naturally to improve the model.It is possible to know the distance carriers are moving,and also consider the timetables of carriers during transportation.Carrier choice,less-than carrier load,and domestic transportation among demand centers are considered as the three target areas to reduce CO2 emissions during the distribution process.The research model was formulated as a mixed integer programming (MIP) problem.It achieves cost reduction,and will contribute to improvement of the natural environment.
文摘A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL) and real-time passenger information system, key just-in-time (JIT) concepts can now be realized in process design and coordinated scheduling to shape a seamless multimodal transit system. JIT refers to a production system that times both movements of goods during production and delivery from suppliers together. It meets the same logic for seamless multimodal services. Therefore, this study innovatively analyzes possible public transportation technologies for JIT uses;moreover, to layout the possible application frame-work of a transportation technology based JIT multimodal transit system for main station area in Taipei city. With this innovative framework, multimodal transit services can deliver to the right place at right time.
基金supported by the Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology (MRE201402)the National Natural Science Foundation of China (41306040, 41225020)the Foundation of Key Laboratory of Yangtze River Water Environment (YRWEF 201305)
文摘The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detritus has developed unique sedimentary systems in the ECS during the Quaternary, offering ideal terrestrial archives for reconstructing Quaternary paleoenvironmental changes and studying land-sea interactions. Overall, two characteristic river systems dominate the sedimentary systems and sediment source to sink transport patterns in the ECS, represented by the Changjiang(Yangtze River) and Huanghe(Yellow River) for the large river system and Taiwan rivers for the small river system. Given this, the sediments derived from both river systems bear distinct features in terms of parent rock lithology, provenance weathering and sediment transport. Previous studies mostly focus on either the ‘source' discrimination or the ‘sink' records of the sedimentary system in the ECS, while the source to sink process linking the land and sea, in particular its time scale, has been poorly understood. Here we introduce a newly-developed dating technique, the ‘comminution age' method, which offers a quantitative constraint on the time scale of sediment transfer from its ultimate source to the final depositional sink. This novel method is of great significance for improving our understanding on the earth surface processes including tectonic-climate driven weathering, and sediment recycling in relation to landscape evolution and marine environmental changes. The application of comminution age method in the ECS will provide important constraints on sediment source-to-sink process and more evidences for the construction of late Quaternary paleoenvironmental changes under these unique sedimentary systems.