Evaluating and diagnosing ecosystem health of the "three-lake" watershed in Yuxi, Yunnan, China from 2010 to 2020 by PSR-KDE.

To carry out the diagnosis and evaluation of the ecosystem health in Yuxi three-lake watershed, this paper presents the changing trend of its health state, and predicts the future development. This also provides ideas for maintaining the regional ecosystem health, and then gradually improves the ecological environment quality. Taking Fuxian Lake, Qilu Lake and Xingyun Lake (the three-lake watershed) in Yuxi City, Yunnan Province, Southwest China as the research object, a model combining pressure-state-response and kernel density estimation (PSR-KDE) adopts to diagnose and evaluate the ecosystem health of the "three lake" watershed from 2010 to 2020, and the distribution map of ecosystem health index has obtained by the evaluation indexes integration based on GIS spatial analysis. Hence, the evaluation results have visualized on the map. The results show that: The distribution of ecosystem health index in the study area was 0.1530-0.7045 in 2010, 0.2056-0.7512 in 2015, and 0.2248-0.7662 in 2020. 0.12% was in the pathological area in 2010. After 2015, the pathological condition of ecosystem health has completely solved, and the proportion of unhealthy ecosystems was 11.95% in 2010, 7.38% in 2015, and 5.97% in 2020. The ecosystem health index of the study region was 0.5523 in 2010, 0.5807 in 2015, and 0.5815 in 2020, it indicates that the ecosystem was in a sub-health state. From 2010 to 2020, the ecosystem health around Qilu Lake was the most worrying, followed by the northwest of Fuxian Lake and the northern and southern regions of Xingyun Lake. The ecosystem health of the three-lake watershed showed significant improvement from 2010 to 2020. The study ecosystem health assessment and early warning in the three-lake watershed is significant to the ecological environment protection and management of the plateau lake basin, the restoration of the territorial space ecology and the economic development of the surrounding area.

Coexistence of superconductivity and charge density wave instability in A15-Nb3Sn.

A15-type compound Nb3Sn has attracted much attention due to its relatively high critical temperature and critical field of superconductivity, making it a leading material for superconducting applications. In this study, we investigate the structural instability and superconductivity of Nb3Sn under hydrostatic pressure using first-principles calculations. We determine the electronic properties, phonon dispersion, electron-phonon coupling and the superconducting gap for Nb3Sn at pressures ranging from ambient to 9 GPa. Our results show that a significant electron density is present near the Fermi level due to the van Hove singularity, indicating the strong electron-phonon coupling. The phonon dispersion of Nb3Sn exhibits Kohn anomalies at three different wave vectors at a lower temperature. Moreover, above a pressure of 6 GPa, the charge density wave (CDW) instability disappeared, suggesting that pressure inhibits the CDW phase. The superconducting temperature is predicted to be TC = 18.62 K under ambient conditions, which is well consistent with the experimental results. We find that both the CDW and superconducting orders respond to pressure, with their transition temperatures decreasing as the pressure increases below 6 GPa. Above 6 GPa, the superconducting transition temperature increases slowly with pressure. Our results suggest that the instability in Nb3Sn is driven by the softening of the phonon modes due to the CDW caused by strong electron-phonon coupling. Therefore, the CDW phase and superconducting phase of Nb3Sn coexist at low pressure.

A review of sustainable utilization and prospect of coal gasification slag.

Currently, the storage of coal gasification slag (CGS) is continuously increasing, as the coal gasification technology develops, posing significant environmental hazards. Due to its volcanic ash characteristics and rich residual carbon, CGS has great potential for resource utilization, which has attracted the attentions of many scholars. This paper firstly introduces the compositions and properties of CGS. Then, it reviews the existing utilization methods of CGS, including Preparation of building materials, carbon-ash separation technology, ecological restoration, and cyclic blending. The advantages and disadvantages of various methods are compared. Subsequently, some high-value utilization methods of coal gasification slag are introduced, such as the preparation of high-performance activated carbon and zeolite, of which the feasibility and advantages are evaluated. Finally, some suggestions are put forward for future developing technologies. This paper aims to provide some references and inspiration for the utilization and environmental protection of CGS.

First assistant experience in total laparoscopic pancreaticoduodenectomy: accelerating the learning curve for an operator.

OBJECTIVE: Compare and analyze clinical data of total laparoscopic pancreaticoduodenectomy (TLPD) cases for surgeons with / without first assistant experience (FAE) in TLPD. Probe influence of FAE in TLPD on the learning curve for an operator. METHODS: The clinical data of 239 patients, that underwent TLPD performed by two surgeons between January 2017 and January 2022) in our department, were consecutively collected and divided into two groups (A and B). Group A cases were operated by Surgeon A, with FAE of 57 TLPDs in our department prior to initial TLPD as an operator. Group B cases were operated by Surgeon B with no FAE of TLPD. Cumulative sum (CUSUM) method developed learning curves. Clinical data and both surgeons' learning curves were statistically compared between both groups. RESULTS: Between both groups, no statistically significant variations were observed for pre-operative health conditions. Reduced surgical duration, blood loss and transfusion volume during surgery, together with reductions in major post-operative complication rates and reduced hospital/ICU stays were identified within Group A, having statistically significant variations. The technical plateau phases of the learning curves were approximately 25-41 cases and 35-51 cases, for Surgeon A and Surgeon B, respectively. CONCLUSION: FAE in TLPD can accelerate the learning curve of TLPD for an operator, with safer surgical procedures and enhanced post-operative recovery.

Ultrathin Aramid/COF Heterolayered Membrane for Solid-State Li-Metal Batteries.

Ultrathin, ultrastrong, and highly conductive solid-state polymer-based composite electrolytes have long been exploited for the next-generation lithium-based batteries. In particular, the lightweight membranes that are less than tens of microns are strongly desired, aiming to maximize the energy densities of solid-state batteries. However, building such ideal membranes are challenging when using traditional materials and fabrication technologies. Here we reported a 7.1 µm thick heterolayered Kevlar/covalent organic framework (COF) composite membrane fabricated via a bottom-up spin layer-by-layer assembly technology that allows for precise control over the structure and thickness of the obtained membrane. Much stronger chemical/mechanical interactions between cross-linked Kevlar and conductive 2D-COF building blocks were designed, resulting in a highly strong and Li+ conductive (1.62 × 10-4 S cm-1 at 30 °C and 4.6 × 10-4 S cm-1 at 70 °C) electrolyte membrane that can prevent solid-state batteries from short-circuiting after over 500 h of cycling. All-solid-state lithium batteries using this membrane enable a significantly improved energy density.

The influence of relative humidity and ground material on indoor walking-induced particle resuspension.

The resuspension of indoor particulate matters caused by people indoor walking could affect indoor air quality and human health. Therefore, it is particularly important to study the resuspension rules of the particulate matters in different indoor environments. The influence of the ground material and the relative humidity on resuspension of the particulate matters were investigated under three kinds of ground materials and three different relative humidity. Results showed that different relative humidity and different ground materials had different effects on the mass concentration of the particulate matters. In addition, different particle sizes had diverse influence on the mass concentration. Compared with low-level loop pile carpet and shaggy carpet, hardwood floor was more conductive to human health which was less likely to cause the resuspension of the particulate matters. At the same time, relative humidity had a great influence on the resuspension of the particulate matters. With the increase of relative humidity, the resuspension rate of fine particulate matters decreased.

Chemoimmunotherapy by combining oxaliplatin with immune checkpoint blockades reduced tumor burden in colorectal cancer animal model.

BACKGROUND: Colorectal cancer (CRC) is among one of the top common cancers worldwide. Developing novel comprehensive treatment strategies is critical for improving survival of late stage CRC patients. Recent advances in immune checkpoint blockades provided a novel strategy for treating cancers via stimulating the antitumor immune response. However, the effects of immune checkpoint blockades were limited in CRC due to intrinsic resistance. Oxaliplatin (OXA) based chemotherapy was the foundation of CRC adjuvant chemotherapy. Here, we investigated the potential roles of OXA in inducing immunogenicity and synergizing with immune checkpoints in CRC. METHOD: Immunogenicity of OXA was tested in CRC cell lines. Immune checkpoint blockades sensitive and resistant CRC models were used to study the potential synergistic roles of OXA with immune checkpoint blockades. RESULTS: We found CT26 mouse model was sensitive to immune checkpoint blockades, while MC38 mouse model was resistant. OXA could induce immunogenic cell death in several human and mouse CRC cell lines. Short term OXA treatment increased immune cell infiltration in MC38 mouse model and therefore enhanced the efficacy of immune checkpoint in MC38 mouse model. As a response to the OXA and immune checkpoint blockades combination, inhibitory immune checkpoints were down-regulated in MC38 tumors, while immune enhancing cytokines were up-regulated. Short term OXA treatment induced antitumor immune response in an immune checkpoint blockades resistant mouse model, therefore synergized with immune checkpoint blockades.

DNA-PKcs interference sensitizes colorectal cancer cells to a mTOR kinase inhibitor WAY-600.

Colorectal cancer (CRC) is one leading contributor of cancer-related mortalities. Mammalian target of rapamycin (mTOR), existing in two complexes (mTORC1/2), is a valuable target for possible CRC interference. In the current study, we showed that WAY-600, a potent mTOR inhibitor, only exerted moderate activity against primary and HT-29 CRC cells. We proposed that DNA-dependent protein kinase catalytic subunit (DNA-PKcs) could be the major resistance factor of WAY-600 in CRC cells. DNA-PKcs inhibitors, including NU7026 and NU7441, dramatically enhanced WAY-600-induced cytotoxic and pro-apoptotic effect against the CRC cells. Further, WAY-600-exerted cytotoxicity was significantly increased in DNA-PKcs-silenced (by targeted siRNA/shRNA) CRC cells, but was attenuated with DNA-PKcs overexpression. Our evidence suggested that DNA-PKcs Thr-2609 phosphorylation might be critical for WAY-600's resistance. Mutation of this site through introducing a dominant negative DNA-PKcs (T2609A) dramatically potentiated WAY-600's sensitivity in HT-29 cells. Meanwhile, overexpression of protein phosphatase 5 (PP5) dephosphorylated DNA-PKcs at Thr-2609, and significantly increased WAY-600's sensitivity in HT-29 cells. In vivo, WAY-600-induced anti-HT-29 xenograft growth activity was significantly potentiated with NU7026 co-administration. These results suggest that DNA-PKcs could be the major resistance factor of WAY-600 in CRC cells.

Staurosporine Induces Platelet Apoptosis Through p38 Mitogen-Activated Protein Kinase Signaling Pathway.

BACKGROUND: Staurosporine (STS), a microbial alkaloid and potent PKC inhibitor, has become one of the most promising anti-cancer drugs. STS effectively induces apoptosis in many nucleated cells; however, it is still unclear whether STS induces apoptosis in enucleated platelets. METHODS: Apoptotic events in platelets treated with STS were assessed by flow cytometry or western blotting. RESULTS: STS induced depolarization of mitochondrial inner transmembrane potential (ΔΨm), up-regulation of Bax and Bak, phosphatidylserine (PS) exposure, release of mitochondrial cytochrome c, and activation of caspase-8 and caspase-9 in human platelets. Furthermore, STS stimulation induced phosphorylation of p38 mitogen-activated protein kinase (MAPK). Inhibition of p38 MAPK activation significantly reduced ΔΨm depolarization and PS exposure in platelets stimulated with STS. CONCLUSIONS: These data indicate that STS induces platelet apoptosis via the p38 MAPK signaling pathway. These findings suggest that platelet apoptosis-related hemorrhage should be noticed in STS and its derivatives in clinical tests.

Optimization of thermal deformation process parameters of 2219 Al matrix composites.

To investigate the deformation behavior and optimize the hot processing parameters for 2219 aluminum matrix composite, the constitutive equation and hot processing maps were established. Initially, hot compression experiments on 2219 aluminum alloy (2219A) were conducted using a Gleeble-3500 thermal simulation tester to obtain high-temperature rheological data. The deformation temperatures tested were 573, 623, 673, 723, and 773 K, with strain rates of 0.01, 0.1, 1, and 10 s-1, and a maximum deformation of 60 %. Subsequently, material parameters such as the activation energy, Zener-Hollomon parameter, power dissipation efficiency, and instability coefficient for 2219A were calculated. Analytical expressions for these material and deformation parameters were formulated, and a hot processing map for 2219A was constructed. The hot processing map, along with the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and the Entropy Weight Method (EWM), were used to optimize the thermal deformation process parameters. The stability processing area and the optimal processing area identified by both methods were largely consistent. According to the hot processing map, the stability processing areas were identified in the temperature ranges of 580-660 K and 690-773 K with strain rates of 0.01 s-1 and 0.01-0.6 s-1, respectively. Using the TOPSIS and EWM methods, the stability processing areas were defined between 573 and 640 K and 0.01 s-1, 640-690 K and 0.01-0.1 s-1, and 690-773 K and 0.01-1 s-1. The consistency and accuracy of these optimization results were confirmed through microstructure analysis.

An efficient molten steel slag gas quenching process: Integrating carbon solidification and waste heat recovery.

The iron and steel-making industries have garnered significant attention in research related to low-carbon transitions and the reuse of steel slag. This industry is known for its high carbon emissions and the substantial amount of steel slag it generates. To address these challenges, a waste heat recovery process route has been developed for molten steel slag, which integrates CO2 capture and fixation as well as efficient utilization of steel slag. This process involves the use of lime kiln flue gas from the steel plant as the gas quenching agent, thereby mitigating carbon emissions and facilitating carbonation conversion of steel slag while simultaneously recovering waste heat. The established carbonation model of steel slag reveals that the insufficient diffusion of CO2 gas molecules within the product layer is the underlying mechanism hindering the carbonation performance of steel slag. This finding forms the basis for enhancing the carbonation performance of steel slag. The results of Aspen Plus simulation indicate that 1 t of steel slag (with a carbonation conversion rate of 15.169 %) can fix 55.19 kg of CO2, process 6.08 kmol of flue gas (with a carbon capture rate of 92.733 %), and recover 2.04 GJ of heat, 0.43 GJ of exergy, and 0.68 MWh of operating cost. These findings contribute to the development of sustainable and efficient solutions for steel slag management, with potential applications in the steel production industry and other relevant fields.

Research on the Hot Deformation Process of A100 Steel Based on High-Temperature Rheological Behavior and Microstructure.

To obtain the optimal hot deformation process, the rheological and dynamic recrystallization behaviors of A100 steel were researched through isothermal compression tests. Firstly, a Hensel-Spittel constitutive model was established based on the stress-strain curves. Secondly, dynamic recrystallization percentage and grain size models were established to identify the necessary conditions for complete dynamic recrystallization. Finally, microstructural analysis was employed to validate the accuracy of the recrystallization model. The results indicate that the flow stress is highly sensitive to both the strain rate and the temperature, and the HS model demonstrates a high predictive accuracy, with a correlation coefficient of 0.9914. There exists a contradictory relationship between decreasing the average grain size and increasing the recrystallization percentage. The higher the percentage of dynamic recrystallization, the larger the average grain size tends to be. This situation should be avoided when devising the actual processing procedures. The optimal hot working processes for achieving complete dynamic recrystallization and a smaller average grain size are as follows: a strain equal to or greater than 0.6, a temperature between 1193 and 1353 K, and a strain rate between 0.1 and 1 s-1.

Knowledge, attitude, and practice of healthcare providers on chronic refractory cough: A cross-sectional study.

Objective: Previous studies from outside China showed that the knowledge, attitudes, and practice (KAP) of chronic refractory cough (CRC) was moderate among physicians. This study examined the KAP toward CRC in Chinese healthcare providers. Methods: This single-center cross-sectional study was conducted at The Sixth Affiliated Hospital of Nantong University, Yancheng Third People's Hospital, from July 2022 to January 2023 and enrolled healthcare providers. The demographic characteristics and KAP scores were collected using a questionnaire (Cronbach's α = 0.934) developed based on CRC guidelines. Results: The study included 539 healthcare providers. The mean knowledge score was 8.27 ± 2.37 (maximum of 14, 59.07%), indicating poor knowledge. The highest rates of inaccuracies pertained to knowledge about the definition of chronic cough, empirical treatment methods, and potential risks of different treatments, suggesting a need for unified training in all aspects of CRC for medical staff. The mean attitude score was 49.74 ± 63.63 (maximum of 60, 82.90%), indicating favorable attitudes. Most healthcare providers believed that CRC affects normal work and life and that it would be necessary to provide more help to patients from the perspectives of drug treatment and psychological counseling. The mean practice score was 23.20 ± 6.28 (maximum of 35, 66.29%), indicating poor practice. Conclusion: This study suggests that healthcare providers in Yancheng have poor knowledge, favorable attitudes, and poor practice of CRC. This study provides points that should be targeted in future training and continuing education activities.

The impact of land use on eco-environment in the Dianchi Basin.

(1) Studying the dynamic correlation between land use and the eco-environment in the Dianchi Basin is important for improving the basin's spatial layout and enhancing ecological development and conservation; (2) Through dynamic analysis and comprehensive evaluation of land use, the introduction of ecological and environmental quality index, and the use of FLUS models, the impacts on eco-environments in the Dianchi Basin for the recent 20 years were analyzed; (3) The past two decades witnessed a constant increase in the construction land in the Dianchi Basin and a decline in the farmland at an average annual rate of 0.93 %; The utilization level of land in the Dianchi Basin presented a negative correlation with the quality of the area's eco-environment, which reduces first and then increases; When natural production becomes a priority, both the construction land and farmland have witnessed growth. However, when ecological protection becomes a priority, it is projected that by 2035, the Dianchi Basin will achieve its highest eco-environmental quality index; (4) Studying how the change of land use types affects eco-environment is crucial for optimizing the current allocation of land resources and promoting sustainable development in the basin.

Aspirin Induces platelet apoptosis.

Aspirin is widely used in the treatment of a number of clinical conditions. Although aspirin is being thought to be a relatively "safe" medicine, it also has some side effects, particularly the risk of bleeding which may be severe and lead to death. The mechanisms, however, are not totally understood. It has been reported recently that aspirin induces apoptosis in many cell types. Thus, the aim of the current study is to explore whether aspirin induces platelet apoptosis. The data show that mitochondrial transmembrane potential (ΔΨm) depolarizations and phosphatidylserine (PS) exposures were dose-dependently induced by aspirin in platelets. To further confirm that aspirin incurs platelet apoptosis, caspase-3 activity was measured in platelets, and the result indicated that aspirin induced caspase-3 activation. Furthermore, the mean volume of platelets incubated with aspirin was obviously reduced. Caspase inhibitor z-VAD-fmk inhibited aspirin induced apoptotic platelet shrinkage and ΔΨm depolarization, but had no effect on PS exposure. In addition, platelets incubated with cyclooxygenase inhibitor indomethacin did not incur ΔΨm depolarazation and PS exposure. Taken together, the data indicate that aspirin induces platelet apoptosis via caspase-3 activation.

[Randomized controlled study of integrated treatment of traditional Chinese medicine and western medicine on AIDS with pulmonary inflammation patients].

OBJECTIVE: To compare effects of integrated treatment traditional Chinese medicine and Western medicine (TCM-WM) and simple western medicine on TCM clincal symptoms in the patient of AIDS with pulmonary inflammation. METHOD: A multicenter randomized controlled trials of 164 subjects evaluated the effects of clinical symptoms of AIDS with pulmonary inflammation of TWO regimens: the TCM-WM group (n = 111) and western medicine treatment group (n = 53), while incidence of TCM symptoms in different time points in two groups were analyzed. RESULT: Twenty eight days after treatment, the cured and markedly effective rate of TCM symptoms in the TCM-WM group significantly exceeding that in the western medicine treatment group (cured and markedly effective rate significant efficiency 44.55% vs 20.00%), while the incidence rate for the TCM symptoms of fever and headache in the TCM-WM group was significantly lower than that in western medicine group. CONCLUSION: The integrated treatment of traditional Chinese medicine and Western medicine helps to alleviate the TCM clinical symptoms of AIDS with pulmonary inflammation.

Perioperative Outcomes and Long-Term Survival of Laparoscopic Pancreaticoduodenectomy: A Retrospective Study of 653 Cases in a Single Institution.

Introduction: Laparoscopic pancreaticoduodenectomy (LPD) is gaining wide acceptance within pancreatic surgery. However, longitudinal data are lacking. The aim of this study was to analyze and assess the short-term outcomes and long-term survival of LPD over a duration of 8 years. Methods: Patients who underwent LPD in our institution between November 2013 and September 2021 were included in this study. The perioperative outcomes were statistically analyzed. The long-term survival was studied over a median follow-up duration of 13 months. Results: In total, 653 consecutive patients treated at our institution were included, of which 617 cases underwent standard LPD and 36 cases underwent LPD with vascular resection. The rate of death in hospital, reoperation, postpancreatectomy hemorrhage, postoperative pancreatic fistula, and delayed gastric emptying were 4.4%, 10.3%, 11.9%, 12.9%, and 6.1% respectively. There were statistical differences in the intraoperative blood loss and transfusion, operation time, and the R0 resection rate between the LPD cases and LPD with vascular resection cases. A total of 526 cases were pathologically diagnosed of cancer. The 1-, 3-, and 5-year survival rates were 49.2%, 17.9%, and 17.9%, respectively, for pancreatic cancer with the median survival time of 12 months. The 1-, 3-, and 5-year survival rates were 76.9%, 60.8%, and 52.5%, respectively, for bile duct cancer with the median survival time of 35 months. The 1-, 3-, and 5-year survival rates were 80.2%, 62.2%, and 52.9%, respectively, for duodenal cancer with the median survival time of 53 months. The 1-, 3-, and 5-year survival rates were 72.5%, 54.5%, and 50%, respectively, for ampullary cancer with the median survival time of 55 months. Conclusion: LPD is a feasible and oncologically acceptable procedure with satisfying perioperative outcomes and long-term survival in a high-volume institution.

Customer knowledge management competence evaluation of agritourism enterprises by using the balanced scorecard and fuzzy-AHP: Evidence from Chengdu-Chongqing economic circle.

This paper provides an evaluation framework to explore the linking mechanisms between customer knowledge management competence (CKMC) and Balanced Scorecard (BSC). With a case study from Chengdu-Chongqing Economic Circle of China, this paper attempts to empirically justify the framework. An index system was established for evaluating CKMC based on BSC and knowledge management process, the weight design and consistency check of the indexes were implemented by using the analytic hierarchy process (AHP), and the overall evaluation value and concrete index scores at all levels were obtained via the fuzzy evaluation method. Empirical results show that CKMC performance measurement indicators were ranked in order of importance as Business process performance dimensions (0.465), System support dimensions (0.289), Customer communication dimensions (0.152) and Market performance dimension (0.094). It also shows that the overall score of CKMC was 3.404, reflecting that the CKMC was in a state of general satisfaction. This research also identifies key factors hindering implementation of CKMC, including Attention from senior leaders (2.871), customer knowledge sharing efficiency (2.928), and information technology level (3.133). This research could contribute to CKM theory by extending customer knowledge management competence research with BSC initiatively. For practitioners, this study may provide useful suggestions to identify key factors promoting business CKMC, and finally promotes sustainable development of Agritourism.

Study on Hot Tensile Deformation Behavior and Hot Stamping Process of GH3625 Superalloy Sheet.

Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800-1050 °C and strain rates of 0.001, 0.01, 0.1, 1, and 10 s-1 on a Gleeble-3500 metallurgical processes simulator. The effect of temperature and holding time on grain growth was investigated to determine the proper heating schedule of the GH3625 sheet in hot stamping. The flow behavior of the GH3625 superalloy sheet was analyzed in detail. The work hardening model (WHM) and the modified Arrhenius model, considering the deviation degree R (R-MAM), were constructed to predict the stress of flow curves. The results showed that WHM and R-MAM have good prediction accuracy by evaluating the correlation coefficient (R) and the average absolute relative error (AARE). Additionally, the plasticity of the GH3625 sheet at elevated temperature drops with the increasing temperature and decreasing strain rate. The best deformation condition of the GH3625 sheet in the hot stamping is in the range of 800~850 °C and 0.1~10 s-1. Finally, a hot stamped part of the GH3625 superalloy was produced successfully, which had higher tensile strength and yield strength than the as-received sheet.

The Quadratic Constitutive Model Based on Partial Derivative and Taylor Series of Ti6242s Alloy and Predictability Analysis.

To solve the problem of insufficient predictability in the classical models for the Ti6242s alloy, a new constitutive model was proposed, based on the partial derivatives from experimental data and the Taylor series. Firstly, hot compression experiments on the Ti6242s alloy at different temperatures and different strain rates were carried out, and the Arrhenius model and Hensel-Spittel model were constructed. Secondly, the partial derivatives of logarithmic stress with respect to temperature and logarithmic strain rate at low, medium and high strain levels were analyzed. Thirdly, two new constitutive models with first- and second-order approximation were proposed to meet the requirements of high precision. In this new model, by analyzing the high-order differential data of experimental data and combining the Taylor series theory, the minimum number of terms that can accurately approximate the experimental rheological data was found, thereby achieving an accurate prediction of flow stress with minimal material parameters. In the new model, by analyzing the high-order differential of the experimental data and combining the theory of the Taylor series, the minimum number of terms that can accurately approximate the experimental rheological data was found, thereby achieving an accurate prediction of flow stress with minimal material parameters. Finally, the prediction accuracies for the classical model and the new model were compared, and the predictabilities for the classical models and the new model were proved by mathematical means. The results show that the prediction accuracies of the Arrhenius model and the Hensel-Spittel model are low in the single-phase region and high in the two-phase region. In addition, second-order approximation is required between the logarithmic stress and logarithmic strain rate, and first-order approximation is required between logarithmic stress and temperature to establish a high-precision model. The order of prediction accuracy of the four models from high to low is the quadratic model, Arrhenius model, linear model and HS model. The prediction accuracy of the quadratic model in all temperatures and strain rates had no significant difference, and was higher than the other models. The quadratic model can greatly improve prediction accuracy without significantly increasing the material parameters.