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A semi-empirical formula for evaluating residual strain of soils under earthquake loading
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作者 袁晓铭 孟上九 孙锐 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期307-313,共7页
A new semi-empirical formula for evaluating the residual strain of soils under earthquake loading is presented in this paper based on the incremental method and the increment model proposed by the authors.When the inc... A new semi-empirical formula for evaluating the residual strain of soils under earthquake loading is presented in this paper based on the incremental method and the increment model proposed by the authors.When the incident loading is uniform,the results calculated by the new formula are nearly the same as those by the existing formula.For excitation of the random earthquake loading,the results calculated by the new formula are compared to the results obtained by dynamic triaxial tests.The dynamic triaxial tests had been performed considering different seismic waves,confining stresses, consolidation ratios,and types of cohesive soils.The comparison between the calculated and tested results indicate that the presented formula can efficiently and practically describe the time-dependent process of the soil residual strains under actual seismic loads. 展开更多
关键词 SOIL residual strain semi-empirical formula carthquake loading
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A new semi-empirical formula for total cross sections of electron scattering from triatomic molecules at 30—5000 eV
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作者 施德恒 刘玉芳 +1 位作者 孙金锋 朱遵略 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第8期438-440,共3页
Total cross sections (TCSs) of electrons scattering from triatomic molecules over the energy range from 30 to 5000 eV are investigated employing a new semi-empirical formula. The TCSs of electrons scattering from tr... Total cross sections (TCSs) of electrons scattering from triatomic molecules over the energy range from 30 to 5000 eV are investigated employing a new semi-empirical formula. The TCSs of electrons scattering from triatomic molecules SO2, NO2, and CO2 are calculated. The quantitative TCSs are in good agreement with those obtained by experiments. It is shown that the results derived from the semi-empirical formula are much closer to the measurements than other calculations. 展开更多
关键词 A new semi-empirical formula for total cross sections of electron scattering from triatomic molecules at 30 EV TCS
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Unraveling the mechanism of action of Shangxia Liangji formula for treating insomnia:a metabolomics and network pharmacology approach
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作者 Xia-Jie Quan Hao Liang +5 位作者 Yong-Hong Tang Li Jiang Xiong-Ying Ji Feng-Ying Zhang Ping Zhang Bo Ouyang 《Traditional Medicine Research》 2025年第2期16-29,共14页
Background:Insomnia is a prevalent clinical condition and Shangxia Liangji formula(SXLJF)is a well-established method of treatment.Nevertheless,the specific mechanism of action of SXLJF remains unclear.Methods:The mou... Background:Insomnia is a prevalent clinical condition and Shangxia Liangji formula(SXLJF)is a well-established method of treatment.Nevertheless,the specific mechanism of action of SXLJF remains unclear.Methods:The mouse model of insomnia was established by intraperitoneal injection of para-chlorophenylalanine.Forty-two mice were randomly divided into a negative control group,model group,SXLJF group(18.72 g/kg/day),and positive control group(diazepam,2 mg/kg)and treated with the corresponding drugs for 7 consecutive days.The open field test and pentobarbital-induced sleeping test were conducted.LC-MS-based untargeted metabolomics and network pharmacology were applied to explore the potential targets of SXLJF for treating insomnia.Finally,key targets were validated using RT-qPCR.Results:Behavioral tests demonstrated that SXLJF reduced the total distance,average velocity,central distance,and sleep latency,and prolonged sleep duration.Metabolomics and network pharmacology revealed potential targets,signaling pathways,metabolic pathways,and metabolites associated with the anti-insomnia effects of SXLJF.Specifically,tyrosine hydroxylase(TH)and tyrosine metabolism emerged as crucial metabolic pathways and targets,respectively.RT-qPCR results supported the role of TH in the mechanism of SXLJF in treating insomnia.Conclusion:In conclusion,TH and tyrosine metabolism may represent significant targets and pathways for SXLJF in treating insomnia. 展开更多
关键词 Shangxia Liangji formula INSOMNIA metabolomics network pharmacology tyrosine hydroxylase tyrosine metabolism
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Fanlian Huazhuo formula:A promising therapeutic approach for metabolic associated steatotic liver disease
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作者 Chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期167-171,共5页
This article reviews the study,“Fanlian huazhuo formula alleviates high-fat-dietinduced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway”published in the World Journal o... This article reviews the study,“Fanlian huazhuo formula alleviates high-fat-dietinduced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway”published in the World Journal of Gastroenterology.The study explores the therapeutic potential of Fanlian Huazhuo formula(FLHZF)in treating metabolic-associated steatotic liver disease(MASLD),demonstrating that FLHZF reduces lipid accumulation,oxidative stress,and liver injury in MASLD models by modulating key signaling pathways involved in lipid metabolism and autophagy.This editorial emphasizes the potential of FLHZF as a treatment for MASLD and calls for further research to verify its clinical efficacy. 展开更多
关键词 Fanlian Huazhuo formula Metabolic associated steatotic liver disease AUTOPHAGY Lipid metabolism Oxidative stress
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Tanyu Tongzhi formula attenuates atherosclerotic plaque vulnerability by inhibiting CD40^(+) monocyte differentiation
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作者 Zheng-Tian Lv Yan-Yun Pan +4 位作者 Chen-Xia Wu Yuan-Gang Qiu Shen-Jie Chen Wei Mao Jin Dai 《Traditional Medicine Research》 2025年第4期61-71,共11页
Background:Atherosclerosis(AS)is a chronic progressive inflammatory disease,and plaque stability plays a critical role in preventing acute events.Tanyu Tongzhi formula(TTF),a traditional Chinese medicine,has potential... Background:Atherosclerosis(AS)is a chronic progressive inflammatory disease,and plaque stability plays a critical role in preventing acute events.Tanyu Tongzhi formula(TTF),a traditional Chinese medicine,has potential therapeutic effects on AS.Methods:We used an AS animal model to examine the effects of TTF on atherosclerotic plaque vulnerability and CD40^(+)monocyte differentiation.AS plaque area,collagen content,and lipid area were assessed using histological staining.AS plaque-related biomarkers(monocyte chemoattractant protein 1(MCP-1),monocyte plus macrophage(MOMA-2),von Willebrand factor(vWF),CD31,and alpha-smooth muscle actin(α-SMA))were detected using immunohistochemistry.Inflammatory cytokines were determined using enzyme-linked immunosorbent assay.CD40 mRNA expression was detected by real-time quantitative PCR.CD40^(+)monocyte differentiation was evaluated by flow cytometry analysis in ApoE-/-mice and peripheral blood mononuclear cells(PBMCs).AMPK/NF-κB signaling pathways-related protein expression was investigated through western blotting.Results:TTF treatment reduced AS plaque area,collagen content,and lipid area in AS model mice.Levels of MCP-1,MOMA-2,vWF,and CD31 were decreased,whileα-SMA level was increased by TTF in model mice.TTF reduced inflammatory cytokines levels,including tumor necrosis factor receptor-α(TNF-α),high-sensitivity C-reactive protein(hs-CRP),and interleukin-6(IL-6).TTF inhibited CD40^(+)monocyte differentiation and decreased the number of CD40^(+)/CD40-and Ly6C^(+)/Ly6C-cells and M1/M2 ratio in AS model mice and human PBMCs.Additionally,TTF modulated the AMPK/NF-κB signaling pathway in human PBMCs.Conclusion:TTF attenuates atherosclerotic plaque vulnerability by inhibiting CD40^(+)monocyte differentiation,possibly through the regulation of the AMPK/NF-κB signaling pathway.These findings suggest that TTF could be a potential therapeutic agent for preventing plaque rupture and subsequent cardiovascular events in patients with AS. 展开更多
关键词 ATHEROSCLEROSIS Tanyu Tongzhi formula CD40^(+)monocyte differentiation inflammation
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QSAR Study of Nitrobenzenes’ Toxicity to Tetrahymena Pyriformis Using Semi-empirical Quantum Chemical Methods 被引量:16
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作者 闫秀芬 肖鹤鸣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期7-14,共8页
The molecular geometries and electronic structures of 30 nitrobenzenes have been calculated by using semi-empirical MO AM1 and PM3 methods. EHOMO, ELUMO, ENHOMO, ENLUMO, AE, QNO2, Qc and V were selected as the structu... The molecular geometries and electronic structures of 30 nitrobenzenes have been calculated by using semi-empirical MO AM1 and PM3 methods. EHOMO, ELUMO, ENHOMO, ENLUMO, AE, QNO2, Qc and V were selected as the structural descriptors. The acute toxicity (-log/C50) of nitrobenzenes to tetrahymena pyriformis along with the above eight structural parameters was used to establish the quantitative structure-activity relationships (QSARs). The results indicate that the established model based on AM I method is superior to that on PM3 method not only for the stability but also for the predictive powers of the model. Based on AM1 parameters, a further classifying discussion was presented for the study of nitrobenzene toxic mechanism. The results show that the substituents, nitro group and halogen substituents on the aromatic ring are crucial to the chemicals' toxicity. For nitrobenzenes without halogen or other substituent, the reduction of nitro group is the main route. However, for those with halogen substituents, their next lowest unoccupied molecular orbital may take part in the toxic action betweeen the chemicals and macromolecules, and ENLUMO has the most important effect on these chemicals' toxicity. 展开更多
关键词 NITROBENZENES TOXICITY QSAR semi-empirical MO orbital methods
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Relationships between moment magnitude and fault parameters:theoretical and semi-empirical relationships 被引量:4
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作者 王海云 陶夏新 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期201-211,共11页
Fault parameters are important in earthquake hazard analysis.In this paper,theoretical relationships between moment magnitude and fault parameters including subsurface rupture length,downdip rupture width,rupture area... Fault parameters are important in earthquake hazard analysis.In this paper,theoretical relationships between moment magnitude and fault parameters including subsurface rupture length,downdip rupture width,rupture area,and average slip over the fault surface are deduced based on seismological theory.These theoretical relationships are further simplified by applying similarity conditions and an unique form is established.Then,combining the simplified theoretical relationships between moment magnitude and fault parameters with seismic source data selected in this study,a practical semi-empirical relationship is established.The seismic source data selected is also to used to derive empirical relationships between moment magnitude and fault parameters by the ordinary least square regression method.Comparisons between semi-empirical relationships and empirical relationships show that the former depict distribution trends of data better than the latter.It is also observed that downdip rupture widths of strike slip faults are saturated when moment magnitude is more than 7.0,but downdip rupture widths of dip slip faults are not saturated in the molnent magnitude rangcs of this study. 展开更多
关键词 earthquake hazard analysis fault paramcters seismic moment moment magnitude semi-empirical relationships.
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Towards a semi-empirical model of the sea ice thickness based on hyperspectral remote sensing in the Bohai Sea 被引量:5
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作者 YUAN Shuai GU Wei +1 位作者 LIU Chengyu XIE Feng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期80-89,共10页
Sea ice thickness is one of the most important input parameters for the prevention and mitigation of sea ice disasters and the prediction of local sea environments and climates. Estimating the sea ice thickness is cur... Sea ice thickness is one of the most important input parameters for the prevention and mitigation of sea ice disasters and the prediction of local sea environments and climates. Estimating the sea ice thickness is currently the most important issue in the study of sea ice remote sensing. With the Bohai Sea as the study area, a semiempirical model of the sea ice thickness(SEMSIT) that can be used to estimate the thickness of first-year ice based on existing water depth estimation models and hyperspectral remote sensing data according to an optical radiative transfer process in sea ice is proposed. In the model, the absorption and scattering properties of sea ice in different bands(spectral dimension information) are utilized. An integrated attenuation coefficient at the pixel level is estimated using the height of the reflectance peak at 1 088 nm. In addition, the surface reflectance of sea ice at the pixel level is estimated using the 1 550–1 750 nm band reflectance. The model is used to estimate the sea ice thickness with Hyperion images. The first validation results suggest that the proposed model and parameterization scheme can effectively reduce the estimation error associated with the sea ice thickness that is caused by temporal and spatial heterogeneities in the integrated attenuation coefficient and sea ice surface. A practical semi-empirical model and parameterization scheme that may be feasible for the sea ice thickness estimation using hyperspectral remote sensing data are potentially provided. 展开更多
关键词 Bohai Sea sea ice thickness hyperspectral remote sensing semi-empirical model
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Comparative Study among Different Semi-Empirical Models for Soil Salinity Prediction in an Arid Environment Using OLI Landsat-8 Data 被引量:1
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作者 A. El-Battay A. Bannari +1 位作者 N. A. Hameid A. A. Abahussain 《Advances in Remote Sensing》 2017年第1期23-39,共17页
Salt-affected soils, caused by natural or human activities, are a common environmental hazard in semi-arid and arid landscapes. Excess salts in soils affect plant growth and production, soil and water quality and, the... Salt-affected soils, caused by natural or human activities, are a common environmental hazard in semi-arid and arid landscapes. Excess salts in soils affect plant growth and production, soil and water quality and, therefore, increase soil erosion and land degradation. This research investigates the performance of five different semi-empirical predictive models for soil salinity spatial distribution mapping in arid environment using OLI sensor image data. This is the first attempt to test remote sensing based semi-empirical salinity predictive models in this area: the Kingdom of Bahrain. To achieve our objectives, OLI data were standardized from the atmosphere interferences, the sensor radiometric drift, and the topographic and geometric distortions. Then, the five semi-empirical predictive models based on the Normalized Difference Salinity Index (NDSI), the Salinity Index-ASTER (SI-ASTER), the Salinity Index-1 (SI-1), the Soil Salinity and Sodicity Index-1 and Index-2 (SSSI-1 and SSSI-2), developed for slight and moderate salinity in agricultural land, were implemented and applied to OLI image data. For validation purposes, a fieldwork was organized and different important spots-locations representing different salinity levels were visited, photographed, and localized using an accurate GPS (σ ≤ ±30 cm). Based on this a priori knowledge of the soil salinity, six validation sites were selected to reflect non-saline, low, moderate, high and extreme salinity classes, descriptive statistics extracted from polygons and/or transects over these sites were used. The obtained results showed that the models based on NDSI, SI-1 and SI-ASTER all failed to detect salinity bounds for both extreme salinity (Sabkhah) and non-saline conditions. In Fact, NDSI and SI-ASTER gave respectively only 35% dS/m and 25% dS/m in extreme salinity validation site, while SI-1 and SI-ASTER indicated 38% dS/m and 39% dS/m in non-saline validation site. Therefore, these three models were deemed inadequate for the study site. However, both SSSI-1 and SSSI-2 allowed a detection of the previous salinity bounds and furthermore described similarly and correctly the urban-vegetation areas and the open-land areas. Their predicted EC is around 10% dS/m for non-saline urban soil, about 25% dS/m for low salinity urban-vegetation soil, approximately 30% to 75% dS/m, respectively, for moderate to high salinity soils. SSSI-2 based semi-empirical salinity models was able to differentiate the high salinity versus extreme salinity in areas where both exist and was very accurate to highlight the pure salt where SSSI-1 has reach saturation for both salinity classes. In conclusion, reliable salinity map was produced using the model based on SSSI-2 and OLI sensor data that allows a better characterization of the soil salinity problem in an Arid Environment. 展开更多
关键词 Soil SALINITY SPECTRAL Indices semi-empirical Models ARID LAND Landsat-OLI
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Application of GC/EIMS in Combination with Semi-Empirical Calculations for Identification and Investigation of Some Volatile Components in Basil Essential Oil 被引量:1
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作者 Mamoun S. M. Abd El-Kareem Mohamed Abd El Fattah Rabbih +2 位作者 Ezzat Taha Mohamed Selim Elsherbiny Abd El-monem Elsherbiny Ayman Yasen El-Khateeb 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第1期14-25,共12页
Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil unde... Volatile components in the extracts of basil leaves (Ocimum basilicum L.) were identified by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) mode. The major volatile components of basil under investigation are α-pinene, sabinene, β-pinene, d-limonene, eucalyptol, l-linalool and estragole. Electron ionization mass spectra of these compounds have been obtained and investigated. Furthermore, the semi-empirical MNDO [Modified Neglect of Diatomic Overlap] method was used to calculate the thermochemical data for the structural properties of these compounds. 展开更多
关键词 Gas Chromatograph Mass Spectrometer semi-empirical Calculations Basil Essential Oil
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A synthetic semi-empirical physical model of secondary electron yield of metals under E-beam irradiation 被引量:1
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作者 封国宝 崔万照 +2 位作者 张娜 曹猛 刘纯亮 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期459-466,共8页
Calculations of secondary electron yield(SEY) by physical formula can hardly accord with experimental results precisely. Simplified descriptions of internal electron movements in the calculation and complex surface ... Calculations of secondary electron yield(SEY) by physical formula can hardly accord with experimental results precisely. Simplified descriptions of internal electron movements in the calculation and complex surface contamination states of real sample result in notable difference between simulations and experiments. In this paper, in order to calculate SEY of metal under complicated surface state accurately, we propose a synthetic semi-empirical physical model. The processes of excitation of internal secondary electron(SE) and movement toward surface can be simulated using this model.This model also takes into account the influences of incident angle and backscattering electrons as well as the surface gas contamination. In order to describe internal electronic states accurately, the penetration coefficient of incident electron is described as a function of material atom number. Directions of internal electrons are set to be uniform in each angle. The distribution of internal SEs is proposed by considering both the integration convergence and the cascade scattering process.In addition, according to the experiment data, relationship among desorption gas quantities, sample ultimate temperature and SEY is established. Comparing with experiment results, this synthetic semi-empirical physical model can describe the SEY of metal better than former formulas, especially in the aspect of surface contaminated states. The proposed synthetic semi-empirical physical model and presented results in this paper can be helpful for further studying SE emission, and offer an available method for estimating and taking advantage of SE emission accurately. 展开更多
关键词 secondary electron yield synthetic semi-empirical physical model metal electron irradiation
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Adaptive semi-empirical model for non-contact atomic force microscopy
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作者 Xi Chen Jun-Kai Tong Zhi-Xin Hu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期682-687,共6页
Non-contact atomic force microscope is a powerful tool to investigate the surface topography with atomic resolution.Here we propose a new approach to estimate the interaction between its tips and samples,which combine... Non-contact atomic force microscope is a powerful tool to investigate the surface topography with atomic resolution.Here we propose a new approach to estimate the interaction between its tips and samples,which combines a semi-empirical model with density functional theory(DFT)calculations.The generated frequency shift images are consistent with the experiment for mapping organic molecules using CuCO,Cu,CuCl,and CuO_(x)tips.This approach achieves accuracy close to DFT calculation with much lower computational cost. 展开更多
关键词 semi-empirical model atomic force microscopy density functional theory functionalized tips
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An improved semi-empirical friction model for gas-liquid two-phase flow in horizontal and near horizontal pipes
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作者 M.Gharehasanlou M.Emamzadeh M.Ameri 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第4期213-223,共11页
Pressure drop and liquid hold-up are two very important fluid flow parameters in design and control of multiphase flow pipelines.Friction factors play an important role in the accurate calculation of pressure drop.Var... Pressure drop and liquid hold-up are two very important fluid flow parameters in design and control of multiphase flow pipelines.Friction factors play an important role in the accurate calculation of pressure drop.Various empirical and semi-empirical closure relations exist in the literature to calculate the liquid-wall,gas-wall and interfacial friction in two-phase pipe flow.However most of them are empirical correlations found under special experimental conditions.In this paper by modification of a friction model available in the literature,an improved semiempirical model is proposed.The proposed model is incorporated in the two-fluid correlations under equilibrium conditions and solved.Pressure gradient and velocity profiles are validated against experimental data.Using the improved model,the pressure gradient deviation from experiments diminishes by about 3%;the no-slip condition at the interface is satisfied and the velocity profile is predicted in better agreement with the experimental data. 展开更多
关键词 Friction factor Numerical simulation semi-empirical friction model Two-phase flow Two-fluid model
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Fanlian Huazhuo Formula alleviates high-fat diet-induced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway 被引量:4
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作者 Meng-Yuan Niu Geng-Ting Dong +9 位作者 Yi Li Qing Luo Liu Cao Xi-Min Wang Qi-Wen Wang Yi-Ting Wang Zhe Zhang Xi-Wen Zhong Wei-Bo Dai Le-Yu Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第30期3584-3608,共25页
BACKGROUND Fanlian Huazhuo Formula(FLHZF)has the functions of invigorating spleen and resolving phlegm,clearing heat and purging turbidity.It has been identified to have therapeutic effects on type 2 diabetes mellitus... BACKGROUND Fanlian Huazhuo Formula(FLHZF)has the functions of invigorating spleen and resolving phlegm,clearing heat and purging turbidity.It has been identified to have therapeutic effects on type 2 diabetes mellitus(T2DM)in clinical application.Non-alcoholic fatty liver disease(NAFLD)is frequently diagnosed in patients with T2DM.However,the therapeutic potential of FLHZF on NAFLD and the underlying mechanisms need further investigation.AIM To elucidate the effects of FLHZF on NAFLD and explore the underlying hepatoprotective mechanisms in vivo and in vitro.METHODS HepG2 cells were treated with free fatty acid for 24 hours to induce lipid accumulation cell model.Subsequently,experiments were conducted with the different concentrations of freeze-dried powder of FLHZF for 24 hours.C57BL/6 mice were fed a high-fat diet for 8-week to establish a mouse model of NAFLD,and then treated with the different concentrations of FLHZF for 10 weeks.RESULTS FLHZF had therapeutic potential against lipid accumulation and abnormal changes in biochemical indicators in vivo and in vitro.Further experiments verified that FLHZF alleviated abnormal lipid metabolism might by reducing oxidative stress,regulating the AMPKα/SREBP-1C signaling pathway,activating autophagy,and inhibiting hepatocyte apoptosis.CONCLUSION FLHZF alleviates abnormal lipid metabolism in NAFLD models by regulating reactive oxygen species,autophagy,apoptosis,and lipid synthesis signaling pathways,indicating its potential for clinical application in NAFLD. 展开更多
关键词 Fanlian Huazhuo formula Nonalcoholic fatty liver disease AUTOPHAGY Apoptosis AMPKα/SREBP-1C signal pathway Oxidative stress
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Simulation of a DI Diesel Engine Performance Fuelled on Biodiesel Using a Semi-Empirical 0D Model
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作者 Claude Valery Ngayihi Abbe Robert Nzengwa +2 位作者 Raidandi Danwe Zacharie Merlin Ayissi Marcel Obounou 《Energy and Power Engineering》 2013年第10期596-603,共8页
Diesel engines have proven over the years important in terms of efficiency and fuel consumption to power generation ratio. Many research works show the potential of biodiesel as a substitute for conventional gasoil. M... Diesel engines have proven over the years important in terms of efficiency and fuel consumption to power generation ratio. Many research works show the potential of biodiesel as a substitute for conventional gasoil. Mainly, previous and recent researches have focused on experimental investigation of diesel engine performance fuelled by biodiesel. Researches on the mathematical description of diesel engine process running on biodiesel are scarce, and mostly about chemical and thermodynamic description of the combustion process of biodiesel rather than performance studies. This work describes a numerical investigation on the performance analysis of a diesel engine fuelled by palm oil biodiesel. The numerical investigation was made using a semi empirical 0D model based on Wiebe’s and Watson’s model which was implemented via the open access numerical calculation software Scilab. The model was validated first by comparing with experimental pressure and performance data of a one cylinder engine at rated speed and secondly by comparing with a six cylinders engine performance data at various crankshaft rotational speeds. Simulations were then made to analyze the engine performance when running on biodiesel. The calculations were made at constant combustion duration and constant coefficient of excess air. Results showed that the model matches the overall experimental data, such as the power output and peak cylinder pressure. The ignition delay was somehow underestimated by the model for the first experiment, which caused a slight gap on in cylinder pressure curve, whereas it predicted the average ignition delay fairly well for the second set of validation. The simulations of engine performance when running on biodiesel confirmed results obtained in previous experimental researches on biodiesel. The model will be further investigated for engine control when shifting to biodiesel fuel. 展开更多
关键词 semi-empirical 0D MODEL SCILAB BIODIESEL PERFORMANCE DIESEL Engine
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Model informed precision medicine of Chinese herbal medicines formulas-A multi-scale mechanistic intelligent model 被引量:1
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作者 Yuanyuan Qian Xiting Wang +8 位作者 Lulu Cai Jiangxue Han Zhu Huang Yahui Lou Bingyue Zhang Yanjie Wang Xiaoning Sun Yan Zhang Aisong Zhu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期585-600,共16页
Recent trends suggest that Chinese herbal medicine formulas(CHM formulas)are promising treatments for complex diseases.To characterize the precise syndromes,precise diseases and precise targets of the precise targets ... Recent trends suggest that Chinese herbal medicine formulas(CHM formulas)are promising treatments for complex diseases.To characterize the precise syndromes,precise diseases and precise targets of the precise targets between complex diseases and CHM formulas,we developed an artificial intelligence-based quantitative predictive algorithm(DeepTCM).DeepTCM has gone through multilevel model calibration and validation against a comprehensive set of herb and disease data so that it accurately captures the complex cellular signaling,molecular and theoretical levels of traditional Chinese medicine(TCM).As an example,our model simulated the optimal CHM formulas for the treatment of coronary heart disease(CHD)with depression,and through model sensitivity analysis,we calculated the balanced scoring of the formulas.Furthermore,we constructed a biological knowledge graph representing interactions by associating herb-target and gene-disease interactions.Finally,we experimentally confirmed the therapeutic effect and pharmacological mechanism of a novel model-predicted intervention in humans and mice.This novel multiscale model opened up a new avenue to combine“disease syndrome”and“macro micro”system modeling to facilitate translational research in CHM formulas. 展开更多
关键词 Chinese herbal medicine formulas Precision medicine Mathematical modeling Systems biology Coronary heart disease Depression ISCHEMIA-REPERFUSION Inflammation
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Salt-Affected Soil Mapping in an Arid Environment Using Semi-Empirical Model and Landsat-OLI Data
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作者 Abderrazak Bannari Ali El-Battay +1 位作者 Nadir Hameid Fadia Tashtoush 《Advances in Remote Sensing》 2017年第4期260-291,共32页
The aim of this research is to map the salt-affected soil in an arid environment using an advanced semi-empirical predictive model, Operational Land Imager (OLI) data, a digital elevation model (DEM), field soil sampl... The aim of this research is to map the salt-affected soil in an arid environment using an advanced semi-empirical predictive model, Operational Land Imager (OLI) data, a digital elevation model (DEM), field soil sampling, and laboratory and statistical analyses. To achieve our objectives, the OLI data were atmospherically corrected, radiometric sensor drift was calibrated, and distortions of topography and geometry were corrected using a DEM. Then, the soil salinity map was derived using a semi-empirical predictive model based on the Soil Salinity and Sodicity Index-2 (SSSI-2). The vegetation cover map was extracted from the Transformed Difference Vegetation Index (TDVI). In addition, accurate DEM of 5-m pixels was used to derive topographic attributes (elevation and slope). Visual comparisons and statistical validation of the semi-empirical model using ground truth were undertaken in order to test its capability in an arid environment for moderate and strong salinity mapping. To accomplish this step, fieldwork was organized and 120 soil samples were collected with various degrees of salinity, including non-saline soil samples. Each one was automatically labeled using a digital camera and an accurate global positioning system (GPS) survey (σ ≤ ± 30 cm) connected in real time to the geographic information system (GIS) database. Subsequently, in the laboratory, the major exchangeable cations (Ca2+, Mg2+, Na+, K+, Cl- and SO42-), pH and the electrical conductivity (EC-Lab) were extracted from a saturated soil paste, as well as the sodium adsorption ratio (SAR) being calculated. The EC-Lab, which is generally accepted as the most effective method for soil salinity quantification was used for statistical analysis and validation purposes. The obtained results demonstrated a very good conformity between the derived soil salinity map from OLI data and the ground truth, highlighting six major salinity classes: Extreme, very high, high, moderate, low and non-saline. The laboratory chemical analyses corroborate these results. Furthermore, the semi-empirical predictive model provides good global results in comparison to the ground truth and laboratory analysis (EC-Lab), with correlation coefficient (R2) of 0.97, an index of agreement (D) of 0.84 (p < 0.05), and low overall root mean square error (RMSE) of 11%. Moreover, we found that topographic attributes have a substantial impact on the spatial distribution of salinity. The areas at a relatively high altitude and with hard bedrock are less susceptible to salinity, while areas at a low altitude and slope (≤2%) composed of Quaternary soil are prone to it. In these low areas, the water table is very close to the surface (≤1 m), and the absence of an adequate drainage network contributes significantly to waterlogging. Consequently, the intrusion and emergence of seawater at the surface, coupled with high temperature and high evaporation rates, contribute extensively to the soil salinity in the study area. 展开更多
关键词 Soil SALINITY REMOTE Sensing Landsat-OLI GIS semi-empirical Model SALINITY SPECTRAL Indices Topographic Attributes ARID Environment
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Improvement of Bare Soil Semi-Empirical Radar Backscattering Models (Oh and Dubois) with SAR Multi-Spectral Satellite Data (X-, C- and L-Bands)
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作者 Rémy Fieuzal Frédéric Baup 《Advances in Remote Sensing》 2016年第4期296-314,共20页
The objective of this study is to improve the performance of semi-empirical radar backscatter models, which are mainly used in microwave remote sensing (Oh 1992, Oh 2004 and Dubois). The study is based on satellite an... The objective of this study is to improve the performance of semi-empirical radar backscatter models, which are mainly used in microwave remote sensing (Oh 1992, Oh 2004 and Dubois). The study is based on satellite and ground data collected on bare soil surfaces during the Multispectral Crop Monitoring experimental campaign of the CESBIO laboratory in 2010 over an agricultural region in southwestern France. The dataset covers a wide range of soil (viewing top soil moisture, surface roughness and texture) and satellite (at different frequencies: X-, C- and L-bands, and different incidence angles: 24.3° to 53.3°) configurations. The proposed methodology consists in identifying and correcting the residues of the models, depending on the surface properties (roughness, moisture, texture) and/or sensor characteristics (frequency, incidence angle). Finally, one model has been retained for each frequency domain. Results show that the enhancements of the models significantly increase the simulation performances. The coefficient of correlation increases of 23% in mean and the simulation errors (RMSE) are reduced to below 2 dB (at the X and C-bands) and to 1 dB at the L-band, compared to the initial models. At the X- and C-bands, the best performances of the modified models are provided by Dubois, whereas Oh 2004 is more suitable for the L-band (r is equal to 0.69, 0.65 and 0.85). Moreover, the modified models of Oh 1992 and 2004 and Dubois, developed in this study, offer a wider domain of validity than the initial formalism and increase the capabilities of retrieving the backscattering signal in view of applications of such approaches to stronglycontrasted agricultural surface states. 展开更多
关键词 semi-empirical Backscatters Model Oh Model Dubois Model Multi-Frequency (X- C- L-Band) Microwave TerraSAR-X Radarsat-2 Alos-PALSAR
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A Cauchy integral formula for(p,q)-monogenic functions withα-weight
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作者 GAO Long DU Xiao-jing +1 位作者 LIU Yue XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期545-553,共9页
Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-... Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic functions withα-weight are given. 展开更多
关键词 (p q)-monogenic functions with-weight Cauchy-Pompeiu formula Cauchy integral formula Cauchy integral theorem
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Explicit Peck formula applied to ground displacement based on an elastic analytical solution for a shallow tunnel
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作者 Fanchao KONG Dechun LU +1 位作者 Qingtao LIN Xiuli DU 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2024年第11期1637-1648,共12页
Using the complex variable method,an elastic analytical solution of the ground displacement caused by a shallow circular tunneling is derived.Non-symmetric deformation relative to the horizontal center line of the tun... Using the complex variable method,an elastic analytical solution of the ground displacement caused by a shallow circular tunneling is derived.Non-symmetric deformation relative to the horizontal center line of the tunnel cross-section is used as a boundary condition.A comparison between the proposed analytical method and the Finite Element Method is carried out to validate the rationality of the obtained analytical solution.Two parameters in the Peck formula,namely the maximum settlement of the ground surface center and the width coefficient of settlement curve,are fitted and determined.We propose a modified Peck formula by considering three input parameters,namely the tunnel depth,tunnel radius,and the tunnel gap.The influence of these three parameters on the modified Peck formula is analyzed.The applicability of the modified Peck formula is further investigated by reference to six engineering projects.The ground surface displacement obtained by the explicit Peck formula is in good agreement with the field data,and the maximum error is only 1.3 cm.The proposed formula can quickly and reasonably predict the ground surface settlement caused by tunnelling. 展开更多
关键词 complex variable method elastic analytical solution maximum settlement formula modified Peck formula
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