AIM: To study the interactive relationship of gallbladder motor function, plasma cholecystokinin (CCK) and cholecystokinin A receptor (CCK-R) of gallbladder in patients with cholesterol stone disease.METHODS: Gallblad...AIM: To study the interactive relationship of gallbladder motor function, plasma cholecystokinin (CCK) and cholecystokinin A receptor (CCK-R) of gallbladder in patients with cholesterol stone disease.METHODS: Gallbladder motility was studied by ultrasonography in 33 patients with gallbladder stone and 10 health subjects as controls. Plasma CCK concentration was measured by radioimmunoassay in fasting status (CCK-f) and in 30 min after lipid test meal (CCK-30).Radioligand method was employed to analyze the amount and activity of CCK-R from 33 gallstone patients having cholecystectomy and 8 persons without gallstone died of severe trauma as controls.RESULTS: The percentage of cholesterol in the gallstone composition was more than 70%. The cholesterol stone type was indicated for the patients with gallbladder stone in this study. Based on the criterion of gallbladder residual fraction of the control group, 33 gallstone patients were divided into two subgroups, contractor group (14 cases)and non-contractor group (19 cases), The concentration of CCK-30 was significantly higher in non-contractor group than that in both contractor group and control group (55.86±3.86 pmol/l vs 37.85±0.88 pmol/l and 37.95±0.74 pmol/L, P＜0.01), but there was no difference between contractor group and control group. Meanwhile no significant difference of the concentration of CCK-f could be observed among three groups. The amount of CCK-R was lower in non-contractor group than those in both control group and contractor group (10.27±0.94 fmol/mg vs24.59±2.39 fmol/mg and 22.66±0.55 fmol/mg, P＜0.01).The activity of CCK-R shown as KD in non-contractor group decreased compared to that in control group and contractor group. Only was the activity of CCK-R lower in contractor group than that in control group. The ejection fraction correlated closely with the amount of CCK-R (r = 0.9683,P＜0.01), and the concentration of CCK-30 correlated negatively with the amount of CCK-R closely (r = -0.9627,P＜0.01).CONCLUSION: The distinctive interac展开更多
A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooli...A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooling air at the constant temperature and humidity.Unlike the previous works on this aspect,the present work was not focused on cooling the stored grain by ventilation with ambient air,but with the refrigerated air.Validation was performed by comparing between predicted and measured grain temperature and grain moisture content for two cases.Predicted data were in reasonable good agreement with measured ones.The model and the parameter values used in the model are applicable for predicting temperature and moisture of stored grains under ventilation conditions.展开更多
The decrease of runoff in the Luanhe river basin, which caused water crisis in Tian-jin for several times, was investigated using discharge data covering the period 1956-2002. The data from the differential integral c...The decrease of runoff in the Luanhe river basin, which caused water crisis in Tian-jin for several times, was investigated using discharge data covering the period 1956-2002. The data from the differential integral curves of the annual runoff indicate that the decreasing point began in 1979 in the six sub-basins. The decrease of runoff in the Luanhe river basin resulted from the combination of climate effects and human activities, in which the latter plays an important role. This can be illustrated by noting that after 1979 the runoff generated by similar precipitation decreased under the condition that the total precipitation did not decrease in the entire basin. As a result, the annual runoff of the Luanhe river basin after 1979 decreased by about 6.46×10^8 m^3 each year. To analyze the runoff characteristics, it is inadequate to seek the runoff trends only and the identification of cyclical component of the runoff as accurate as possible is necessary. From the natural annual runoff discharge time series, we can see the annual runoff fluctuates around the long-term average. Analyzed by VRL （Variable Record Length） method, the main periods of 3, 5-6, 7, 9, 16-20 and 37-39 years were found. The last decade causing water crisis was the driest period in the history, and this condition will last several years from trend analysis and power spectrum analysis. So finding new water sources is urgent to solve water crisis in Tianjin city, and the South-North Water Transfer is a feasible option.展开更多
This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved ca...This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.展开更多
Introduction:Riparian vegetation plays a crucial role in soil conservation and riverbank reinforcement.The Three Gorges hydrologic project has significantly changed the pattern of water-level fluctuation and riparian ...Introduction:Riparian vegetation plays a crucial role in soil conservation and riverbank reinforcement.The Three Gorges hydrologic project has significantly changed the pattern of water-level fluctuation and riparian environment,which significantly influenced plant community development and its effect on soil conservation and riverbank protection.Cynodon dactylon,a perennial grass with developed root system and creeping stems,has become a dominant riparian species in the Three Gorges area after the completion of the dam.We aimed to characterize how the soil-root system under the C.dactylon community responded to environmental changes and effects of the soil-root system on shallow soil conservation and riverbank reinforcement through field investigation and laboratory test.Methods:We conducted a field survey and experimental research.Quadrates of a natural C.dactylon community were set up on a riverbank along an altitude gradient.Plants were sampled randomly for the measurements of spatial structure and tensile strength of roots.Soil erosion resistance,soil scour resistance,and shear strength of sampled soil-root systems and control soil were tested in the laboratory.Results:Roots of the C.dactylon community significantly increased soil erosion resistance,soil scour resistance,and shear strength,enhancing the stability of shallow soil and riverbank.Due to water-level fluctuation,C.dactylon at lower altitudes was subjected to less time exposed to air.As a result,the soil-root systems at lower altitudes were characterized by reduced biomass with reduced capacity for soil reinforcement as measured through erosion resistance,soil scour resistance,and shear strength.The correlation analysis indicated that root biomass had a significant positive linear correlation with the enhancement of erosion resistance and scour resistance,and shear strength,respectively.Conclusions:Roots of the C.dactylon community effectively enhanced the stability of riparian shallow soil and riverbank.The fluctuation in water level caused the di展开更多
The basal activity of JNK is low in normal growing cells and inactivated JNK targets p53 for ubiquitination. To elucidate if the C-terminal part of JNK is responsible for its binding to p53, the low background tet-off...The basal activity of JNK is low in normal growing cells and inactivated JNK targets p53 for ubiquitination. To elucidate if the C-terminal part of JNK is responsible for its binding to p53, the low background tet-off inducible NIH3T3 cell line was selected by luciferase reporter gene and a double stable C-JNK Aa (203-424) cell line was established. After withdrawing tetracycline, the C-JNK fragment expression was induced and cell growth was dramati- cally inhibited 24 h later. However, the expresion of p53 was found to be increased after the induction of C-JNK fragment, evaluated by transfecting p21waf-luciferase reporter genes. Our further studies showed that C-JNK fragment could form complex with p53 both in vivo and in vitro. Induction of C-JNK fragment in vivo can increase p53 stability by inhibiting p53 ubiquitination.展开更多
Interleukin-7 （IL-7） is an essential cytokine for the development and homeostatic maintenance of T and B lymphocytes. Binding of IL-7 to its cognate receptor, the IL-7 receptor （IL-7R）, activates multiple pathways...Interleukin-7 （IL-7） is an essential cytokine for the development and homeostatic maintenance of T and B lymphocytes. Binding of IL-7 to its cognate receptor, the IL-7 receptor （IL-7R）, activates multiple pathways that regulate lymphocyte survival, glucose uptake, proliferation and differentiation. There has been much interest in understanding how IL-7 receptor signaling is modulated at multiple interconnected network levels. This review examines how the strength of the signal through the IL-7 receptor is modulated in T and B cells, including the use of shared receptor components, signaling crosstalk, shared interaction domains, feedback loops, integrated gene regulation, multimerization and ligand competition. We discuss how these network control mechanisms could integrate to govern the properties of IL-7R signaling in lymphocytes in health and disease. Analysis of IL-7 receptor signaling at a network level in a systematic manner will allow for a comprehensive approach to understanding the impact of multiple signaling pathways on lymphocyte biology. Cellular ＆ Molecular Immunology.展开更多
In today’s society, the incidence of cardiopulmonary diseases is increasing annually, seriously affecting patients’ quality of life. Therefore, developing a scientific and effective rehabilitation training program i...In today’s society, the incidence of cardiopulmonary diseases is increasing annually, seriously affecting patients’ quality of life. Therefore, developing a scientific and effective rehabilitation training program is of great significance. This study first analyzes the theoretical basis of cardiopulmonary rehabilitation training, including the effects of aerobic exercise, interval training, and strength training on cardiopulmonary function. Based on this, a comprehensive rehabilitation training program is designed, which includes personalized training plans, comprehensive interventions, multidisciplinary collaboration, patient education, and regular follow-up visits. The cardiopulmonary rehabilitation training plan developed in this study has certain scientific practicability, which provides a theoretical basis for cardiopulmonary rehabilitation training, and also provides a reference for medical institutions, rehabilitation centers and communities, which is helpful for promotion and application to a wider range of patients with cardiopulmonary diseases.展开更多
Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to o...Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to our hospital from January 2023 to December 2023 were randomly divided into two groups, the control group (50 cases) was given task-oriented training assisted by nurses, and the observation group (50 cases) was given lower limb rehabilitation robot with task-oriented training. Lower limb balance, lower limb muscle strength, motor function, ankle function, knee flexion range of motion and walking ability were observed. Results: After treatment, the scores of BBS, quadriceps femoris and hamstrings in the observation group were significantly higher than those in the control group (P Conclusion: In the clinical treatment of stroke patients, the combination of task-oriented training and lower limb rehabilitation robot can effectively improve the lower limb muscle strength, facilitate the recovery of balance function, and have a significant effect on the recovery of motor function, which can improve the walking ability of stroke patients and the range of motion of knee flexion, and achieve more ideal therapeutic effectiveness.展开更多
Large-scale pre-training has shown remarkable performance in building open-domain dialogue systems.However,previous works mainly focus on showing and evaluating the conversational performance of the released dialogue ...Large-scale pre-training has shown remarkable performance in building open-domain dialogue systems.However,previous works mainly focus on showing and evaluating the conversational performance of the released dialogue model,ignoring the discussion of some key factors towards a powerful human-like chatbot,especially in Chinese scenarios.In this paper,we conduct extensive experiments to investigate these under-explored factors,including data quality control,model architecture designs,training approaches,and decoding strategies.We propose EVA2.0,a large-scale pre-trained open-domain Chinese dialogue model with 2.8 billion parameters,and will make our models and codes publicly available.Automatic and human evaluations show that EVA2.0 significantly outperforms other open-source counterparts.We also discuss the limitations of this work by presenting some failure cases and pose some future research directions on large-scale Chinese open-domain dialogue systems.展开更多
The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory ...The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.展开更多
The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic ...The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic frequencies of cylinder section,cone section and dust hopper were calculated as f_(1)=53 Hz,f_(2)=65 Hz,and f_(3)=8 Hz by using Fast Fourier Transform(FFT)method,respectively.Based on the effects of f3 on the motion of vortex,the separated space was divided into none affected region,weakly affected region,and strongly affected region.The characteristic frequency of dust hopper increased with the decrease of dust hopper diameter,while it was independent of the height.The dust hopper with d=1.5D(model D3)and h=1.5D(model H3)can significantly decrease the effect of back-mixing on the motion of inner vortex,which is beneficial to improve the efficiency of cyclone separator.展开更多
Introduction:Soil microbial community plays a crucial role in the ecological processes of soil ecosystem.Forest species introduction often changes profoundly soil ecological processes in the forest.Larix kaempferi(Lam...Introduction:Soil microbial community plays a crucial role in the ecological processes of soil ecosystem.Forest species introduction often changes profoundly soil ecological processes in the forest.Larix kaempferi(Lam.)was introduced to China from Japan as a timber tree species in the 1960s.The activity and functional diversity of soil microorganisms in the L.kaempferi forest in Dalaoling National Forest Park in Hubei Province,China,was studied to evaluate the effects of this exotic species on the local soil ecosystems.Methods:Quadrates were set up randomly in the L.kaempferi forests cultivated in 1990 and 1996 and the surrounding Pinus armandii forest cultivated in 1990.Soil samples were collected using a soil corer at five locations along the diagonals in each quadrat.The activity and functional diversity of soil microorganisms were tested using the BIOLOG technique in laboratory.Results:The diversity,activity,and carbon utilization pattern of soil microorganism community and soil physicochemical properties were all impacted by the introduced species.The average well color development(AWCD)and Shannon’s richness index(H)of the soil microorganism community in the L.kaempferi forest decreased with the increase in forest age and were significantly lower than those in the surrounding native P.armandii forest.The carbon source utilization pattern of soil microorganism community in a 23-year-old L.kaempferi forest differed significantly from a 17-year-old L.kaempferi forest and the P.armandii forest.The introduced species also resulted in the changes of soil physicochemical properties.The organic material content,total nitrogen,available nitrogen,and total phosphorus in the soil of L.kaempferi forest were significantly lower than those in the soil of P.armandii forest.Conclusions:Introduction and long-time cultivation of L.kaempferi significantly altered the soil microbial functional diversity and activity and the soil physicochemical properties.The alteration increased with the increase of forest age.展开更多
Lactic acid bacteria(LAB)fermentation is the simplest and safest way of food preservation,and the use of probiotics in yoghurt could provide dairy products with unique flavors,textures and health benefits.In this stud...Lactic acid bacteria(LAB)fermentation is the simplest and safest way of food preservation,and the use of probiotics in yoghurt could provide dairy products with unique flavors,textures and health benefits.In this study,Lactobacillus bulgaricus,Streptococcus thermophilus,L.reuteri DSMZ 8533 and the potential probiotic strain L.plantarum A3 were used for the milk fermentation.Results found the texture properties such as hardness,consistency,and viscosity of the yoghurt were enhanced in the mixed culture condition.Furthermore,components like amino acid(leucine),vanilla(vanillin),C;(unsaturated fatty acids)were also accumulated in L.plantarum A3 fermented yoghut,which leads to the significant sensory profiling difference compared with the former plain yoghurt.All these results proved L.plantarum A3 is a potential probiotic stom winch could enhance the sensory and nutrition profiling of the fermented milk.Future work still needs to be done on the synergistic interaction between the traditional strains and the probiotics during the fermentation process.展开更多
The installed capacity of renewable energy generation has continued to grow rapidly in recent years along with the global energy transition towards a 100%renewable-based power system.At the same time,the grid-connecte...The installed capacity of renewable energy generation has continued to grow rapidly in recent years along with the global energy transition towards a 100%renewable-based power system.At the same time,the grid-connected large-scale renewable energy brings significant challenges to the safe and stable operation of the power system due to the loss of synchronous machines.Therefore,self-synchronous wind turbines have attracted wide attention from both academia and industry.However,the understanding of the physical operation mechanisms of self-synchronous wind turbines is not clear.In particular,the transient characteristics and dynamic processes of wind turbines are fuzzy in the presence of grid disturbances.Furthermore,it is difficult to design an adaptive fault ride-through(FRT)control strategy.Thus,a dual-mode switching FRT control strategy for self-synchronous wind turbines is developed.Two FRT control strategies are used.In one strategy,the amplitude and phase of the internal potential are directly calculated according to the voltage drop when a minor grid fault occurs.The other dual-mode switching control strategy in the presence of a deep grid fault includes three parts:vector control during the grid fault,fault recovery vector control,and self-synchronous control.The proposed control strategy can significantly mitigate transient overvoltage,overcurrent,and multifrequency oscillation,thereby resulting in enhanced transient stability.Finally,simulation results are provided to validate the proposed control strategy.展开更多
To meet the commercial requirements of inorganic heat insulators,the mixture of diatomite and Ca(OH)2 are evenly dispersed,mold-compacted,and then hydrothermally solidified due to the formation of tobermorite under an...To meet the commercial requirements of inorganic heat insulators,the mixture of diatomite and Ca(OH)2 are evenly dispersed,mold-compacted,and then hydrothermally solidified due to the formation of tobermorite under an autoclaved process.Systematic investigations of the preparation conditions(including mix ratio,autoclaved factors,mold pressure,etc)were carried out to optimize the serving properties of such tobermorite-based products.As a result,a compressive strength of more than 30 MPa was realized for the specimen in high density(about 1.30(g·cm-3)).On the contrary,the specimen in light weight for example 0.63(g·cm-3)typically showed a thermal conductivity of around 0.12(W·m-1·K-1).The present work developed a feasible way to produce and to control the serving properties of diatomite-based heat insulators by a process of hydrothermal solidification,in which the optimized value of Ca/Si ratio was proposed to be 0.6~0.7,while the water content is 25% in weight,and hydrothermal reaction is performed at 180 ℃ for no more than 24 hours.展开更多
Through the field survey of traditional rural settlement,it has found that the typical spatial construction model shows the duality of matrix and landmark and they are in a relation of reciprocal causality.However,und...Through the field survey of traditional rural settlement,it has found that the typical spatial construction model shows the duality of matrix and landmark and they are in a relation of reciprocal causality.However,under the impact of urbanization and modernization,this spatial construction model is disappearing,and those natural villages are integrated and reconstructed at a high speed and in a large scale during the construction of new rural communities,leading to a lack of geographical construction system and a damage of ecological living environment.In the perspective of prototype theory,the duality feature should be combined with spatial construction model to guide the inheritance and application of spatial construction model of traditional rural settlements and seek for new spatial development approach for new rural communities based on the sustainable,alternative and transformation strategies.展开更多
The present building facility management status in China resulted in many problems such as high energy consumption,failure of automation control,services failure and poor indoor air quality.Based on questionnaires and...The present building facility management status in China resulted in many problems such as high energy consumption,failure of automation control,services failure and poor indoor air quality.Based on questionnaires and interviews to professional engineers and building users,a comprehensive evaluation index system was established on facility management of high-rise office buildings.A Fuzzy AHP based upon hierarchy criteria system was established.A Fuzzy AHP Evaluation Model on Facility Management System was set up;α-cut analysis was introduced and incorporated with expert knowledge together,which made up the optimism index λ.The fuzzy optimum crisp weight of each criterion was resulted from data-mining.Case investigations were processed in high-rise office buildings in Shenyang.The results illustrated that indoor air quality,thermal comfort and life cycle cost were the most important indexes in the evaluation of Facility Management System of high rise office buildings.Residents in high-rise buildings in Shenyang pay less attention to maintenance management and environment protection.By comparison with the analysis result of Export Choice,Fuzzy AHP-based evaluation model could act as a scientific reference for the establishment of governmental standards in facility management area in building.展开更多
The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off betwe...The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1：5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density（PSD）, the root mean square（RMS） of weighed acceleration, peak factor, average absorbed power（AAP） and vibration dose value（VDV） are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency（z axis） is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the ＂A little uncomfortable＂ and ＂Rather uncomfortable＂. From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1：5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1：5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.展开更多
基金Supported by the Science Development Foundation of Shanghai,No. 95411902
文摘AIM: To study the interactive relationship of gallbladder motor function, plasma cholecystokinin (CCK) and cholecystokinin A receptor (CCK-R) of gallbladder in patients with cholesterol stone disease.METHODS: Gallbladder motility was studied by ultrasonography in 33 patients with gallbladder stone and 10 health subjects as controls. Plasma CCK concentration was measured by radioimmunoassay in fasting status (CCK-f) and in 30 min after lipid test meal (CCK-30).Radioligand method was employed to analyze the amount and activity of CCK-R from 33 gallstone patients having cholecystectomy and 8 persons without gallstone died of severe trauma as controls.RESULTS: The percentage of cholesterol in the gallstone composition was more than 70%. The cholesterol stone type was indicated for the patients with gallbladder stone in this study. Based on the criterion of gallbladder residual fraction of the control group, 33 gallstone patients were divided into two subgroups, contractor group (14 cases)and non-contractor group (19 cases), The concentration of CCK-30 was significantly higher in non-contractor group than that in both contractor group and control group (55.86±3.86 pmol/l vs 37.85±0.88 pmol/l and 37.95±0.74 pmol/L, P＜0.01), but there was no difference between contractor group and control group. Meanwhile no significant difference of the concentration of CCK-f could be observed among three groups. The amount of CCK-R was lower in non-contractor group than those in both control group and contractor group (10.27±0.94 fmol/mg vs24.59±2.39 fmol/mg and 22.66±0.55 fmol/mg, P＜0.01).The activity of CCK-R shown as KD in non-contractor group decreased compared to that in control group and contractor group. Only was the activity of CCK-R lower in contractor group than that in control group. The ejection fraction correlated closely with the amount of CCK-R (r = 0.9683,P＜0.01), and the concentration of CCK-30 correlated negatively with the amount of CCK-R closely (r = -0.9627,P＜0.01).CONCLUSION: The distinctive interac
文摘A mathematical model based on the theory of heat and mass transfer in porous media was developed to simulate the evolution of grain temperature and moisture content in a wheat storage bin during ventilation with cooling air at the constant temperature and humidity.Unlike the previous works on this aspect,the present work was not focused on cooling the stored grain by ventilation with ambient air,but with the refrigerated air.Validation was performed by comparing between predicted and measured grain temperature and grain moisture content for two cases.Predicted data were in reasonable good agreement with measured ones.The model and the parameter values used in the model are applicable for predicting temperature and moisture of stored grains under ventilation conditions.
基金China Education Foundation National Natural Science Foundation of China, No.50579049
文摘The decrease of runoff in the Luanhe river basin, which caused water crisis in Tian-jin for several times, was investigated using discharge data covering the period 1956-2002. The data from the differential integral curves of the annual runoff indicate that the decreasing point began in 1979 in the six sub-basins. The decrease of runoff in the Luanhe river basin resulted from the combination of climate effects and human activities, in which the latter plays an important role. This can be illustrated by noting that after 1979 the runoff generated by similar precipitation decreased under the condition that the total precipitation did not decrease in the entire basin. As a result, the annual runoff of the Luanhe river basin after 1979 decreased by about 6.46×10^8 m^3 each year. To analyze the runoff characteristics, it is inadequate to seek the runoff trends only and the identification of cyclical component of the runoff as accurate as possible is necessary. From the natural annual runoff discharge time series, we can see the annual runoff fluctuates around the long-term average. Analyzed by VRL （Variable Record Length） method, the main periods of 3, 5-6, 7, 9, 16-20 and 37-39 years were found. The last decade causing water crisis was the driest period in the history, and this condition will last several years from trend analysis and power spectrum analysis. So finding new water sources is urgent to solve water crisis in Tianjin city, and the South-North Water Transfer is a feasible option.
基金National Natural Science Foundation of China Under Grant No.50908216Postdoctoral Science Foundation of China Under Grant No.20070420878
文摘This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.
基金by a National Key Technology R&D Program of China(2012BAC06B02-04).
文摘Introduction:Riparian vegetation plays a crucial role in soil conservation and riverbank reinforcement.The Three Gorges hydrologic project has significantly changed the pattern of water-level fluctuation and riparian environment,which significantly influenced plant community development and its effect on soil conservation and riverbank protection.Cynodon dactylon,a perennial grass with developed root system and creeping stems,has become a dominant riparian species in the Three Gorges area after the completion of the dam.We aimed to characterize how the soil-root system under the C.dactylon community responded to environmental changes and effects of the soil-root system on shallow soil conservation and riverbank reinforcement through field investigation and laboratory test.Methods:We conducted a field survey and experimental research.Quadrates of a natural C.dactylon community were set up on a riverbank along an altitude gradient.Plants were sampled randomly for the measurements of spatial structure and tensile strength of roots.Soil erosion resistance,soil scour resistance,and shear strength of sampled soil-root systems and control soil were tested in the laboratory.Results:Roots of the C.dactylon community significantly increased soil erosion resistance,soil scour resistance,and shear strength,enhancing the stability of shallow soil and riverbank.Due to water-level fluctuation,C.dactylon at lower altitudes was subjected to less time exposed to air.As a result,the soil-root systems at lower altitudes were characterized by reduced biomass with reduced capacity for soil reinforcement as measured through erosion resistance,soil scour resistance,and shear strength.The correlation analysis indicated that root biomass had a significant positive linear correlation with the enhancement of erosion resistance and scour resistance,and shear strength,respectively.Conclusions:Roots of the C.dactylon community effectively enhanced the stability of riparian shallow soil and riverbank.The fluctuation in water level caused the di
基金supported by National Natural Science Foundation of China(No.30270556)The National Basic Research Program(No.2002CB513004).
文摘The basal activity of JNK is low in normal growing cells and inactivated JNK targets p53 for ubiquitination. To elucidate if the C-terminal part of JNK is responsible for its binding to p53, the low background tet-off inducible NIH3T3 cell line was selected by luciferase reporter gene and a double stable C-JNK Aa (203-424) cell line was established. After withdrawing tetracycline, the C-JNK fragment expression was induced and cell growth was dramati- cally inhibited 24 h later. However, the expresion of p53 was found to be increased after the induction of C-JNK fragment, evaluated by transfecting p21waf-luciferase reporter genes. Our further studies showed that C-JNK fragment could form complex with p53 both in vivo and in vitro. Induction of C-JNK fragment in vivo can increase p53 stability by inhibiting p53 ubiquitination.
文摘Interleukin-7 （IL-7） is an essential cytokine for the development and homeostatic maintenance of T and B lymphocytes. Binding of IL-7 to its cognate receptor, the IL-7 receptor （IL-7R）, activates multiple pathways that regulate lymphocyte survival, glucose uptake, proliferation and differentiation. There has been much interest in understanding how IL-7 receptor signaling is modulated at multiple interconnected network levels. This review examines how the strength of the signal through the IL-7 receptor is modulated in T and B cells, including the use of shared receptor components, signaling crosstalk, shared interaction domains, feedback loops, integrated gene regulation, multimerization and ligand competition. We discuss how these network control mechanisms could integrate to govern the properties of IL-7R signaling in lymphocytes in health and disease. Analysis of IL-7 receptor signaling at a network level in a systematic manner will allow for a comprehensive approach to understanding the impact of multiple signaling pathways on lymphocyte biology. Cellular ＆ Molecular Immunology.
文摘In today’s society, the incidence of cardiopulmonary diseases is increasing annually, seriously affecting patients’ quality of life. Therefore, developing a scientific and effective rehabilitation training program is of great significance. This study first analyzes the theoretical basis of cardiopulmonary rehabilitation training, including the effects of aerobic exercise, interval training, and strength training on cardiopulmonary function. Based on this, a comprehensive rehabilitation training program is designed, which includes personalized training plans, comprehensive interventions, multidisciplinary collaboration, patient education, and regular follow-up visits. The cardiopulmonary rehabilitation training plan developed in this study has certain scientific practicability, which provides a theoretical basis for cardiopulmonary rehabilitation training, and also provides a reference for medical institutions, rehabilitation centers and communities, which is helpful for promotion and application to a wider range of patients with cardiopulmonary diseases.
文摘Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to our hospital from January 2023 to December 2023 were randomly divided into two groups, the control group (50 cases) was given task-oriented training assisted by nurses, and the observation group (50 cases) was given lower limb rehabilitation robot with task-oriented training. Lower limb balance, lower limb muscle strength, motor function, ankle function, knee flexion range of motion and walking ability were observed. Results: After treatment, the scores of BBS, quadriceps femoris and hamstrings in the observation group were significantly higher than those in the control group (P Conclusion: In the clinical treatment of stroke patients, the combination of task-oriented training and lower limb rehabilitation robot can effectively improve the lower limb muscle strength, facilitate the recovery of balance function, and have a significant effect on the recovery of motor function, which can improve the walking ability of stroke patients and the range of motion of knee flexion, and achieve more ideal therapeutic effectiveness.
基金supported by the 2030 National Key AI Program of China(No.2021ZD0113304)the National Science Foundation for Distinguished Young Scholars(No.62125604)+2 种基金the NSFC projects(Key project with No.61936010 and regular project with No.61876096)the Guoqiang Institute of Tsinghua University,China(Nos.2019GQG1 and 2020GQG0005)Tsinghua-Toyota Joint Research Fund.
文摘Large-scale pre-training has shown remarkable performance in building open-domain dialogue systems.However,previous works mainly focus on showing and evaluating the conversational performance of the released dialogue model,ignoring the discussion of some key factors towards a powerful human-like chatbot,especially in Chinese scenarios.In this paper,we conduct extensive experiments to investigate these under-explored factors,including data quality control,model architecture designs,training approaches,and decoding strategies.We propose EVA2.0,a large-scale pre-trained open-domain Chinese dialogue model with 2.8 billion parameters,and will make our models and codes publicly available.Automatic and human evaluations show that EVA2.0 significantly outperforms other open-source counterparts.We also discuss the limitations of this work by presenting some failure cases and pose some future research directions on large-scale Chinese open-domain dialogue systems.
基金the National Natural Science Foundation of China (Grant Nos. 50371048 and 50372035)the Natural Science Foundation of Shandong Province of China (Grant No. Y2007F11)
文摘The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.
基金gratefully acknowledge the support from the Fundamental Research Funds for the Central Universities/the Development Fund of State Key Laboratory of Heavy Oil Processing(grant No.20CX02215A)the Natural Science Foundation of Shandong Province(grant No.ZR2021ME036)the National Natural Science Foundation of China(grant No.51806248).
文摘The dynamic characteristics of flow field in cyclone separators with different dust hopper structures were studied by coupling Reynolds Stress Model(RSM)and Lagrangian Particle Tracking(LPT)methods.The characteristic frequencies of cylinder section,cone section and dust hopper were calculated as f_(1)=53 Hz,f_(2)=65 Hz,and f_(3)=8 Hz by using Fast Fourier Transform(FFT)method,respectively.Based on the effects of f3 on the motion of vortex,the separated space was divided into none affected region,weakly affected region,and strongly affected region.The characteristic frequency of dust hopper increased with the decrease of dust hopper diameter,while it was independent of the height.The dust hopper with d=1.5D(model D3)and h=1.5D(model H3)can significantly decrease the effect of back-mixing on the motion of inner vortex,which is beneficial to improve the efficiency of cyclone separator.
基金by the National Natural Science Foundation of China(51379105).
文摘Introduction:Soil microbial community plays a crucial role in the ecological processes of soil ecosystem.Forest species introduction often changes profoundly soil ecological processes in the forest.Larix kaempferi(Lam.)was introduced to China from Japan as a timber tree species in the 1960s.The activity and functional diversity of soil microorganisms in the L.kaempferi forest in Dalaoling National Forest Park in Hubei Province,China,was studied to evaluate the effects of this exotic species on the local soil ecosystems.Methods:Quadrates were set up randomly in the L.kaempferi forests cultivated in 1990 and 1996 and the surrounding Pinus armandii forest cultivated in 1990.Soil samples were collected using a soil corer at five locations along the diagonals in each quadrat.The activity and functional diversity of soil microorganisms were tested using the BIOLOG technique in laboratory.Results:The diversity,activity,and carbon utilization pattern of soil microorganism community and soil physicochemical properties were all impacted by the introduced species.The average well color development(AWCD)and Shannon’s richness index(H)of the soil microorganism community in the L.kaempferi forest decreased with the increase in forest age and were significantly lower than those in the surrounding native P.armandii forest.The carbon source utilization pattern of soil microorganism community in a 23-year-old L.kaempferi forest differed significantly from a 17-year-old L.kaempferi forest and the P.armandii forest.The introduced species also resulted in the changes of soil physicochemical properties.The organic material content,total nitrogen,available nitrogen,and total phosphorus in the soil of L.kaempferi forest were significantly lower than those in the soil of P.armandii forest.Conclusions:Introduction and long-time cultivation of L.kaempferi significantly altered the soil microbial functional diversity and activity and the soil physicochemical properties.The alteration increased with the increase of forest age.
基金supported by the National Natural Science Foundation of China[32072192,31901668,31671869]Key Research and Development Project of Zhejiang Province[2020C02042]+4 种基金the Natural Science Foundation of Zhejiang Province[LY19C200005]the Natural Science Foundation of Ningbo(202003N4129)the Open Project Program of the First-Class Bioengineering Disciplines in Zhejiang Province[KF2020007]the Graduate General Program of the Education Department in Zhejiang Province[Y202045625]the K.C.Wong Magna Fund in Ningbo University。
文摘Lactic acid bacteria(LAB)fermentation is the simplest and safest way of food preservation,and the use of probiotics in yoghurt could provide dairy products with unique flavors,textures and health benefits.In this study,Lactobacillus bulgaricus,Streptococcus thermophilus,L.reuteri DSMZ 8533 and the potential probiotic strain L.plantarum A3 were used for the milk fermentation.Results found the texture properties such as hardness,consistency,and viscosity of the yoghurt were enhanced in the mixed culture condition.Furthermore,components like amino acid(leucine),vanilla(vanillin),C;(unsaturated fatty acids)were also accumulated in L.plantarum A3 fermented yoghut,which leads to the significant sensory profiling difference compared with the former plain yoghurt.All these results proved L.plantarum A3 is a potential probiotic stom winch could enhance the sensory and nutrition profiling of the fermented milk.Future work still needs to be done on the synergistic interaction between the traditional strains and the probiotics during the fermentation process.
基金supported in part by the National Natural Science Foundation of China (No.52007174)。
文摘The installed capacity of renewable energy generation has continued to grow rapidly in recent years along with the global energy transition towards a 100%renewable-based power system.At the same time,the grid-connected large-scale renewable energy brings significant challenges to the safe and stable operation of the power system due to the loss of synchronous machines.Therefore,self-synchronous wind turbines have attracted wide attention from both academia and industry.However,the understanding of the physical operation mechanisms of self-synchronous wind turbines is not clear.In particular,the transient characteristics and dynamic processes of wind turbines are fuzzy in the presence of grid disturbances.Furthermore,it is difficult to design an adaptive fault ride-through(FRT)control strategy.Thus,a dual-mode switching FRT control strategy for self-synchronous wind turbines is developed.Two FRT control strategies are used.In one strategy,the amplitude and phase of the internal potential are directly calculated according to the voltage drop when a minor grid fault occurs.The other dual-mode switching control strategy in the presence of a deep grid fault includes three parts:vector control during the grid fault,fault recovery vector control,and self-synchronous control.The proposed control strategy can significantly mitigate transient overvoltage,overcurrent,and multifrequency oscillation,thereby resulting in enhanced transient stability.Finally,simulation results are provided to validate the proposed control strategy.
文摘To meet the commercial requirements of inorganic heat insulators,the mixture of diatomite and Ca(OH)2 are evenly dispersed,mold-compacted,and then hydrothermally solidified due to the formation of tobermorite under an autoclaved process.Systematic investigations of the preparation conditions(including mix ratio,autoclaved factors,mold pressure,etc)were carried out to optimize the serving properties of such tobermorite-based products.As a result,a compressive strength of more than 30 MPa was realized for the specimen in high density(about 1.30(g·cm-3)).On the contrary,the specimen in light weight for example 0.63(g·cm-3)typically showed a thermal conductivity of around 0.12(W·m-1·K-1).The present work developed a feasible way to produce and to control the serving properties of diatomite-based heat insulators by a process of hydrothermal solidification,in which the optimized value of Ca/Si ratio was proposed to be 0.6~0.7,while the water content is 25% in weight,and hydrothermal reaction is performed at 180 ℃ for no more than 24 hours.
文摘Through the field survey of traditional rural settlement,it has found that the typical spatial construction model shows the duality of matrix and landmark and they are in a relation of reciprocal causality.However,under the impact of urbanization and modernization,this spatial construction model is disappearing,and those natural villages are integrated and reconstructed at a high speed and in a large scale during the construction of new rural communities,leading to a lack of geographical construction system and a damage of ecological living environment.In the perspective of prototype theory,the duality feature should be combined with spatial construction model to guide the inheritance and application of spatial construction model of traditional rural settlements and seek for new spatial development approach for new rural communities based on the sustainable,alternative and transformation strategies.
文摘The present building facility management status in China resulted in many problems such as high energy consumption,failure of automation control,services failure and poor indoor air quality.Based on questionnaires and interviews to professional engineers and building users,a comprehensive evaluation index system was established on facility management of high-rise office buildings.A Fuzzy AHP based upon hierarchy criteria system was established.A Fuzzy AHP Evaluation Model on Facility Management System was set up;α-cut analysis was introduced and incorporated with expert knowledge together,which made up the optimism index λ.The fuzzy optimum crisp weight of each criterion was resulted from data-mining.Case investigations were processed in high-rise office buildings in Shenyang.The results illustrated that indoor air quality,thermal comfort and life cycle cost were the most important indexes in the evaluation of Facility Management System of high rise office buildings.Residents in high-rise buildings in Shenyang pay less attention to maintenance management and environment protection.By comparison with the analysis result of Export Choice,Fuzzy AHP-based evaluation model could act as a scientific reference for the establishment of governmental standards in facility management area in building.
基金Supported by Special Fund for Argo-scientific Research in the Public Interest,China(Grant No.201203024)National Natural Science Foundation of China(Grant No.51175498)
文摘The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1：5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density（PSD）, the root mean square（RMS） of weighed acceleration, peak factor, average absorbed power（AAP） and vibration dose value（VDV） are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency（z axis） is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the ＂A little uncomfortable＂ and ＂Rather uncomfortable＂. From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1：5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1：5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.
