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Evolution and Prospects of Foundation Models: From Large Language Models to Large Multimodal Models 被引量:1
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作者 Zheyi Chen Liuchang Xu +5 位作者 Hongting Zheng Luyao Chen Amr Tolba Liang Zhao Keping Yu Hailin Feng 《Computers, Materials & Continua》 SCIE EI 2024年第8期1753-1808,共56页
Since the 1950s,when the Turing Test was introduced,there has been notable progress in machine language intelligence.Language modeling,crucial for AI development,has evolved from statistical to neural models over the ... Since the 1950s,when the Turing Test was introduced,there has been notable progress in machine language intelligence.Language modeling,crucial for AI development,has evolved from statistical to neural models over the last two decades.Recently,transformer-based Pre-trained Language Models(PLM)have excelled in Natural Language Processing(NLP)tasks by leveraging large-scale training corpora.Increasing the scale of these models enhances performance significantly,introducing abilities like context learning that smaller models lack.The advancement in Large Language Models,exemplified by the development of ChatGPT,has made significant impacts both academically and industrially,capturing widespread societal interest.This survey provides an overview of the development and prospects from Large Language Models(LLM)to Large Multimodal Models(LMM).It first discusses the contributions and technological advancements of LLMs in the field of natural language processing,especially in text generation and language understanding.Then,it turns to the discussion of LMMs,which integrates various data modalities such as text,images,and sound,demonstrating advanced capabilities in understanding and generating cross-modal content,paving new pathways for the adaptability and flexibility of AI systems.Finally,the survey highlights the prospects of LMMs in terms of technological development and application potential,while also pointing out challenges in data integration,cross-modal understanding accuracy,providing a comprehensive perspective on the latest developments in this field. 展开更多
关键词 Artificial intelligence large language models large multimodal models foundation models
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Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis 被引量:4
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作者 Jong Mi Park Masoud Rahmati +2 位作者 Sang Chul Lee Jae Il Shin Yong Wook Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1584-1592,共9页
Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse ... Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease itself.Stem cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s disease.Mesenchymal stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of teratogenicity.We performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal model.We searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,2023.The study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control groups.We use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the meta-analysis.Treatment with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational test.Among the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a protective effect on dopaminergic neurons.Subgroup analysis of the amphetamine-induced rotation test showed a significant reduction only in the intracranial-striatum route(SMD[95%CI]=-2.59[-3.25 to-1.94],P=0.0001,I^(2)=74.4%).The memory test showed significant improvement only in the intravenous route(SMD[95%CI]=4.80[1.84 to 7.76],P=0.027,I^(2)=79.6%).Mesenchymal stem cells have been shown to positively impact motor function and memory function and protect dopaminergic neurons in preclinical models of Parkinson’s disease.Further research is required to determine the optimal stem cell types,modifications,transplanted cell numbe rs,and delivery methods for these protocols. 展开更多
关键词 ANIMAL animal experimentation mesenchymal stem cells models Parkinson’s disease stem cell transplantation
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Evaluation of the effects of health education interventions for hypertensive patients based on the health belief model 被引量:1
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作者 Hong-Mei Wang Ying Chen +1 位作者 Yan-Hua Shen Xiao-Mei Wang 《World Journal of Clinical Cases》 SCIE 2024年第15期2578-2585,共8页
BACKGROUND Hypertension is a major risk factor for cardiovascular disease and stroke,and its prevalence is increasing worldwide.Health education interventions based on the health belief model(HBM)can improve the knowl... BACKGROUND Hypertension is a major risk factor for cardiovascular disease and stroke,and its prevalence is increasing worldwide.Health education interventions based on the health belief model(HBM)can improve the knowledge,attitudes,and behaviors of patients with hypertension and help them control their blood pressure.AIM To evaluate the effects of health education interventions based on the HBM in patients with hypertension in China.METHODS Between 2021 and 2023,140 patients with hypertension were randomly assigned to either the intervention or control group.The intervention group received health education based on the HBM,including lectures,brochures,videos,and counseling sessions,whereas the control group received routine care.Outcomes were measured at baseline,three months,and six months after the intervention and included blood pressure,medication adherence,self-efficacy,and perceived benefits,barriers,susceptibility,and severity.RESULTS The intervention group had significantly lower systolic blood pressure[mean difference(MD):-8.2 mmHg,P<0.001]and diastolic blood pressure(MD:-5.1 mmHg,P=0.002)compared to the control group at six months.The intervention group also had higher medication adherence(MD:1.8,P<0.001),self-efficacy(MD:12.4,P<0.001),perceived benefits(MD:3.2,P<0.001),lower perceived barriers(MD:-2.6,P=0.001),higher perceived susceptibility(MD:2.8,P=0.002),and higher perceived severity(MD:3.1,P<0.001)than the control group at six months.CONCLUSION Health education interventions based on the HBM effectively improve blood pressure control and health beliefs in patients with hypertension and should be implemented in clinical practice and community settings. 展开更多
关键词 HYPERTENSION Health education Health belief model Blood pressure control Randomized controlled trial
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Effects of Andrade and Burgers rheologies on glacial isostatic adjustment modeling in Antarctica
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作者 Alexandre Boughanemi Anthony Mémin 《Geodesy and Geodynamics》 EI CSCD 2024年第5期429-440,共12页
Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present i... Variations in ice mass deform the Earth and modify its gravity field,a process known as Glacial Isostatic Adjustment(GIA).GIA in Antarctica remains poorly constrained due to the cumulative effect of past and present ice-mass changes,the unknown history of the past ice-mass change,and the uncertainties on the mechanical properties of the Earth.This paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the commonly used Maxwell rheology,to model GIA-induced deformation in Antarctica.The Love number and Green's function formalism are used to compute the radial surface displacements and the gravity changes induced by the past and present ice-mass changes.We consider an Earth model whose elastic properties and radial structure are averaged from the Preliminary Reference Earth Model and two viscosity profiles to account for the recently published results on the present ice-mass changes.Using the three rheological laws affects the temporal response of the Earth differently,leading to smaller discrepancies than those induced by the two viscosity structures.The differences are the largest between Maxwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-mass change.Results show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial time scales,up to 10 m more than Maxwell.Considering only the recent ice-mass changes,the deformation rates derived from Burgers and Andrade rheologies are several times larger than those estimated by Maxwell rheology. 展开更多
关键词 GIA ANTARCTICA modelING RHEOLOGY Displacement VISCOSITY GNSS
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An extended micromechanical-based plastic damage model for understanding water effects on quasi-brittle rocks
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作者 Qiaojuan Yu Shigui Du +3 位作者 Qizhi Zhu Zhanyou Luo Sili Liu Lunyang Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期289-304,共16页
Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models.However,few studies have established a comprehensive link between the microscopic mechani... Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models.However,few studies have established a comprehensive link between the microscopic mechanisms of water-related micro-crack and the constitutive behaviors of rocks.In this work,we shall propose an extended micromechanical-based plastic damage model for understanding weakening effect induced by the presence of water between micro-crack’s surfaces on quasi-brittle rocks,based on the Mori-Tanaka homogenization and irreversible thermodynamics framework.Regarding the physical mechanism,water strengthens micro-crack propagation,which induces damage evolution during the pre-and post-stage,and weakens the elastic effective properties of rock matrix.After proposing a special calibration procedure for the determination of model parameters based on the laboratory compression tests,the proposed micromechanical-based model is verified by comparing the model predictions to the experimental results.The model effectively captures the mechanical behaviors of quasibrittle rocks subjected to the weakening effects of water. 展开更多
关键词 Water MICRO-CRACK DAMAGE MICRO-MECHANICS Constitutive model Cohesive force
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Exploring the effects of taurolidine on tumor weight and microvessel density in a murine model of osteosarcoma
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作者 LISANNE K.A.NEIJENHUIS LEUTA L.NAUMANN +2 位作者 SONIA A.M.FERKEL SAMUEL J.S.RUBIN STEPHAN ROGALLA 《Oncology Research》 SCIE 2024年第7期1163-1172,共10页
Background:Osteosarcoma is the most common malignant primary bone tumor.The prognosis for patients with disseminated disease remains very poor despite recent advancements in chemotherapy.Moreover,current treatment reg... Background:Osteosarcoma is the most common malignant primary bone tumor.The prognosis for patients with disseminated disease remains very poor despite recent advancements in chemotherapy.Moreover,current treatment regimens bear a significant risk of serious side effects.Thus,there is an unmet clinical need for effective therapies with improved safety profiles.Taurolidine is an antibacterial agent that has been shown to induce cell death in different types of cancer cell lines.Methods:In this study,we examined both the antineoplastic and antiangiogenic effects of taurolidine in animal models of osteosarcoma.K7M2 murine osteosarcoma cells were injected,both intramuscular and intraperitoneal,into 60 BALB/c mice on day zero.Animals were then randomized to receive treatment with taurolidine 2%(800 mg/kg),taurolidine 1%(400 mg/kg),or NaCl 0.9%control for seven days by intravenous or intraperitoneal administration.Results:After 35 days,mice were euthanized,and the tumors were harvested for analysis.Eighteen mice were excluded from the analysis due to complications.Body weight was significantly lower in the 2%taurolidine intraperitoneal treatment group from day 9 to 21,consistent with elevated mortality in this group.Intraperitoneal tumor weight was significantly lower in the 1%(p=0.003)and 2%(p=0.006)intraperitoneal taurolidine treatment groups compared to the control.No antineoplastic effects were observed on intramuscular tumors or for intravenous administration of taurolidine.There were no significant differences in microvessel density or mitotic rate between treatment groups.Reduced body weight and elevated mortality in the 2%taurolidine intraperitoneal group suggest that the lower 1%dose is preferable.Conclusions:In conclusion,there is no evidence of antiangiogenic activity,and the antitumor effects of taurolidine on osteosarcoma observed in this study are limited.Moreover,its toxic profile grants further evaluation.Given these observations,further research is necessary to refine the use of taurolidine in osteosarcoma treatment. 展开更多
关键词 OSTEOSARCOMA TAUROLIDINE Cancer treatment CHEMOTHERAPY Murine models
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Effects of carrier density and interactions on pairing symmetry in a t_(2g) model
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作者 李云霄 西文翰 +3 位作者 董召阳 姚子健 于顺利 李建新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期223-230,共8页
By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the ... By utilizing the fluctuation exchange approximation method,we perform a study on the superconducting pairing symmetry in a t_(2g) three-orbital model on the square lattice.Although the tight-binding parameters of the model are based on Sr_(2)RuO_(4),we have systematically studied the evolution of superconducting pairing symmetry with the carrier density and interactions,making our findings relevant to a broader range of material systems.Under a moderate Hund’s coupling,we find that spin fluctuations dominate the superconducting pairing,leading to a prevalent spin-singlet pairing with a d_(x^(2)-y^(2))-wave symmetry for the carrier density within the range of n=1.5-4 per site.By reducing the Hund’s coupling,the charge fluctuations are enhanced and play a crucial role in determining the pairing symmetry,leading to a transition of the pairing symmetry from the spin-singlet d_(x^(2)-y^(2))-wave to the spin-triplet p-wave.Furthermore,we find that the superconducting pairings are orbital dependent.As the carrier density changes from n=4 to n=1.5,the active orbitals for superconducting pairing shift from the quasi-two-dimensional orbital dxy to the quasi-one-dimensional orbitals d_(xz) and d_(yz). 展开更多
关键词 unconventional superconductivity pairing mechanism Fermi surface three-orbital model
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Assessing the effects of model parameter assumptions on surface-wave inversion results
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作者 Xuezhen Zhang Xiaodong Song 《Earthquake Science》 2024年第6期529-545,共17页
Surface-wave inversion is a powerful tool for revealing the Earth's internal structure.However,aside from shear-wave velocity(v_(S)),other parameters can influence the inversion outcomes,yet these have not been sy... Surface-wave inversion is a powerful tool for revealing the Earth's internal structure.However,aside from shear-wave velocity(v_(S)),other parameters can influence the inversion outcomes,yet these have not been systematically discussed.This study investigates the influence of various parameter assumptions on the results of surface-wave inversion,including the compressional and shear velocity ratio(v_(P)/v_(S)),shear-wave attenuation(Q_(S)),density(ρ),Moho interface,and sedimentary layer.We constructed synthetic models to generate dispersion data and compared the obtained results with different parameter assumptions with those of the true model.The results indicate that the v_(P)/v_(S) ratio,Q_(S),and density(ρ) have minimal effects on absolute velocity values and perturbation patterns in the inversion.Conversely,assumptions about the Moho interface and sedimentary layer significantly influenced absolute velocity values and perturbation patterns.Introducing an erroneous Mohointerface depth in the initial model of the inversion significantly affected the v_(S) model near that depth,while using a smooth initial model results in relatively minor deviations.The assumption on the sedimentary layer not only affects shallow structure results but also impacts the result at greater depths.Non-linear inversion methods outperform linear inversion methods,particularly for the assumptions of the Moho interface and sedimentary layer.Joint inversion with other data types,such as receiver functions or Rayleigh wave ellipticity,and using data from a broader period range or higher-mode surface waves,can mitigate these deviations.Furthermore,incorporating more accurate prior information can improve inversion results. 展开更多
关键词 shear-wave velocity model surface-wave inversion Moho interface sedimentary layer non-linear inversion
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Key Issues for Modelling, Operation, Management and Diagnosis of Lithium Batteries: Current States and Prospects
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作者 Bo Yang Yucun Qian +2 位作者 Jianzhong Xu Yaxing Ren Yixuan Chen 《Energy Engineering》 EI 2024年第8期2085-2091,共7页
1 Introduction.With the continuous growth of the global population,the energy demand continues to increase.However,due to the dominance of fossil fuels in global energy and fossil fuels are non-renewable,it has led to... 1 Introduction.With the continuous growth of the global population,the energy demand continues to increase.However,due to the dominance of fossil fuels in global energy and fossil fuels are non-renewable,it has led to the global energy crisis[1].Besides,the use of fossil fuels will generate a mass of air pollutants(e.g.,carbon dioxide,sulfur dioxide,etc.),which will cause serious environmental pollution,climate change[2],etc.To resolve the aforementioned issues,countries around the world have implemented a variety of measures hoping to fundamentally adjust the global energy structure and achieve sustainable development.Thereinto,“Paris Agreement”reached in 2015 under the framework of“United Nations Framework Convention on Climate Change”aims to control the increase in the average temperature of the globe to within 2°C below preindustrial levels,and thereafter to peak global greenhouse gas emissions as soon as possible,continuously decreasing thereafter[3].United Kingdom plans to reduce the average exhaust emissions of“new cars”to approximately 50–70 g/km by 20230,which is roughly half of what it is now[4].In addition,China proposed a plan at“United Nations General Assembly”in 2020 to peak carbon dioxide emissions by 2030 and strive to achieve carbon neutrality by 2060.It is a fact that the whole world is committed to changing the current energy structure,protecting the Earth’s ecology,and achieving global sustainable development[5]. 展开更多
关键词 Lithium batteries optimization operation modelLING state estimation life prediction fault diagnosis
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Comparisons of Wave Force Model Effects on the Structural Responses and Fatigue Loads of a Semi-Submersible Floating Wind Turbine
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作者 HAN Yanqing LE Conghuan +1 位作者 ZHANG Puyang XU Shengnan 《Journal of Ocean University of China》 CAS CSCD 2024年第1期69-79,共11页
The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a ... The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a semi-submersible floating wind turbine(SFWT)were conducted.Simulations were performed by employing the Morison equation(ME)with linear or second-order wave kinematics and potential flow theory(PFT)with first-or second-order wave forces.A comparison of regular waves,irregular waves,and coupled wind/waves analyses with the experimental data showed that many of the simulation results and experimental data are relatively consistent.However,notable discrepancies are found in the response amplitude operators for platform heave,tower base bending moment,and tension in mooring lines.PFT models give more satisfactory results of heave but more significant discrepan-cies in tower base bending moment than the ME models.In irregular wave analyses,low-frequency resonances were captured by PFT models with second-order difference-frequency terms,and high-frequency resonances were captured by the ME models or PFT models with second-order sum-frequency terms.These force models capture the response frequencies but do not reasonably predict the response amplitudes.The coupled wind/waves analyses showed more satisfactory results than the wave-only analyses.However,an important detail to note is that this satisfactory result is based on the overprediction of wind-induced responses. 展开更多
关键词 floating wind turbine wave force model potential flow theory Morison equation second-order wave forces
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Adaptive Random Effects/Coefficients Modeling
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作者 George J. Knafl 《Open Journal of Statistics》 2024年第2期179-206,共28页
Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using general... Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time. 展开更多
关键词 Adaptive Regression Correlated Outcomes Extended Linear Mixed modeling Fractional Polynomials Likelihood Cross-Validation Random Effects/Coefficients
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Ornithine aspartate effects on bacterial composition and metabolic pathways in a rat model of steatotic liver disease
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作者 Elisa Carolina Lange Pabulo Henrique Rampelotto +3 位作者 Larisse Longo Laura Bainy Rodrigues de Freitas Carolina Uribe-Cruz Mario Reis Alvares-da-Silva 《World Journal of Hepatology》 2024年第5期832-842,共11页
BACKGROUND Metabolic-dysfunction associated steatotic liver disease(MASLD)is a hepatic manifestation of metabolic syndrome.Studies suggest ornithine aspartate(LOLA)as drug therapy.AIM To analyze the influence of LOLA ... BACKGROUND Metabolic-dysfunction associated steatotic liver disease(MASLD)is a hepatic manifestation of metabolic syndrome.Studies suggest ornithine aspartate(LOLA)as drug therapy.AIM To analyze the influence of LOLA intake on gut microbiota using a nutritional model of MASLD.METHODS Adult male Sprague Dawley rats were randomized into three groups:Control(10 rats fed with a standard diet),MASLD(10 rats fed with a high-fat and choline-deficient diet),and LOLA(10 rats receiving 200 mg/kg/d LOLA,after the 16th week receiving high-fat and choline-deficient diet).After 28 wk of the experiment,animals were euthanized,and feces present in the intestine were collected.Following fecal DNA extraction,the V4 region of the 16S rRNA gene was amplified followed by sequencing in an Ion S5™system.RESULTS Alpha and beta diversity metrics were comparable between MASLD and LOLA.3 OTUs were differentially abundant between MASLD and LOLA,which belong to the species Helicobacter rodentium,Parabacteroides goldsteinii,and Parabacteroides distasonis.The functional prediction provided two different metabolic profiles between MASLD and LOLA.The 9 pathways differentially abundant in MASLD are related to a change in energy source,adenosine/purine nucleotides degradation as well as guanosine and adenosine deoxyribonucleotides biosynthesis.The 14 pathways differentially abundant in LOLA are associated with four major metabolic functions primarily influenced by L-aspartate,including tricarboxylic acid cycle pathways,purine/guanosine nucleotides biosynthesis,pyrimidine ribonucleotides biosynthesis and salvage as well as lipid IVA biosynthesis.CONCLUSION Although LOLA had no influence on alpha and beta diversity in this nutritional model of MASLD,it was associated with changes in specific gut microbes and their related metabolic pathways. 展开更多
关键词 Animal model Gut microbiota Metabolic-associated steatotic liver disease Metabolic prediction Ornithine aspartate
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Drivers for Inter-city Innovation Networks Across Chinese Cities:Modelling Physical Versus Intangible Effects
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作者 GAO Yujie SCHERNGELL Thomas NEULÄNDTNER Martina 《Chinese Geographical Science》 SCIE CSCD 2024年第4期706-721,共16页
Cross-region innovation is widely recognized as an important source of the long-term regional innovation capacity.In the recent past,a growing number of studies has investigated the network structure and mechanisms of... Cross-region innovation is widely recognized as an important source of the long-term regional innovation capacity.In the recent past,a growing number of studies has investigated the network structure and mechanisms of cross-region innovation collaboration in various contexts.However,existing research mainly focuses on physical effects,such as geographical distance and high-speed railway connections.These studies ignore the intangible drivers in a changing environment,the more digitalized economy and the increasingly solidified innovation network structure.Thus,the focus of this study is on estimating determinants of innovation networks,especially on intangible drivers,which have been largely neglected so far.Using city-level data of Chinese patents(excluding Hong Kong,Macao,and Taiwan Province of China),we trace innovation networks across Chinese cities over a long period of time.By integrating a measure on Information and Communications Technology(ICT)development gap and network structural effects into the general proximity framework,this paper explores the changing mechanisms of Chinese innovation networks from a new perspective.The results show that the structure of cross-region innovation networks has changed in China.As mechanisms behind this development,the results confirm the increasingly important role of intangible drivers in Chinese inter-city innovation collaboration when controlling for effects of physical proximity,such as geographical distance.Since digitalization and coordinated development are the mainstream trends in China and other developing countries,these countries'inter-city innovation collaboration patterns will witness dramatic changes under the influence of intangible drivers. 展开更多
关键词 inter-city innovation network co-patents information and communications technology development network structural effect spatial interaction model China
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Effects of Polygala fallax Hemsl Water Extract on a Mouse Model of Gastric Motility Disorders
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作者 Liangyin ZHU Xiaofeng HAO +8 位作者 Liuqi HUANG Zongyuan CHEN Wenfeng CHEN Liu YANG Bingchen HUANG Liyuan LI Aipeng LI Suoyi HUANG Xiuzhen SU 《Medicinal Plant》 2024年第4期101-106,共6页
[Objectives]To explore the effects of Polygona fallax Hemsl water extract on gastrointestinal motility in normal mice and gastric motility disorder model mice and approximate mechanism.[Methods]Using normal mice and m... [Objectives]To explore the effects of Polygona fallax Hemsl water extract on gastrointestinal motility in normal mice and gastric motility disorder model mice and approximate mechanism.[Methods]Using normal mice and mice with gastric motility disorders(modeled with atropine),the effects of different mass concentration groups of P.fallax Hemsl water extract(0.125,0.250,0.500 g/mL)and domperidone groups on gastric residual rate,small intestine propulsion rate,serum motilin(MLT),vasoactive intestinal peptide(VIP),and tissue morphology were studied.[Results]There was a highly significant difference(P<0.01)in the small intestine propulsion rate of liquid in normal mice among the different concentration groups of P.fallax Hemsl water extract compared to the blank group.The small intestine propulsion rate and gastric residue rate of semi-solid paste were statistically significant compared to the blank group(P<0.05).Among them,there was a highly significant difference between the high concentration group(67.75%±7.65%,46.5%±10.62%)and the medium concentration group(60.90%±5.87%,59.27%±7.82%)(P<0.01).There was statistical significance in normal mouse serum MLT content in the high concentration group(P<0.05).There was no effect on serum VIP levels in normal mice;no effect on the morphology of stomach and intestinal tissues of normal mice.The small intestine propulsion rate and gastric residue rate of liquid and semi-solid paste in mice with gastric motility disorders were statistically significant compared to the atropine group,with extremely significant differences(P<0.01).[Conclusions]P.fallax Hemsl water extract has a promoting effect on gastrointestinal motility.One of the specific mechanisms by which P.fallax Hemsl promotes gastrointestinal motility in normal mice may be related to the content of MLT in mouse serum.The mechanism of action in atropine induced gastric paresis mice may be related to the reactivation of M receptors,and the action mechanism of P.fallax Hemsl does not change the original histological basis.It can be inferred that P.fallax Hemsl water extract has a synergistic effect on promoting gastrointestinal motility through other mechanisms,but it is not fully understood and further in-depth research is needed. 展开更多
关键词 Polygala fallax Hemsl Gastric motility Mouse model Gastric emptying Gastric paresis MOTILIN Vasoactive intestinal peptide
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Effects of invigorating-spleen and anticancer prescription on extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway in colon cancer mice model
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作者 Wei Wang Jing Wang +2 位作者 Xiu-Xiu Ren Hai-Long Yue Zheng Li 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4468-4476,共9页
BACKGROUND Colon cancer(CC)is one of the most common malignant tumors in the gastrointestinal system.Overall,CC had the third highest incidence but the second highest mortality rate globally in 2020.Nowadays,CC is mai... BACKGROUND Colon cancer(CC)is one of the most common malignant tumors in the gastrointestinal system.Overall,CC had the third highest incidence but the second highest mortality rate globally in 2020.Nowadays,CC is mainly treated with capecitabine chemotherapy regimen,supplemented by radiotherapy,immunotherapy and targeted therapy,but there are still limitations,so Chinese medicine plays an important role.AIM To investigate the effects of invigorating-spleen and anticancer prescription(ISAP)on body weight,tumor inhibition rate and expression levels of proteins in extracellular-signal-regulated kinase(ERK)/mitogen-activated protein kinase(MAPK)signaling pathway in CC mice model.METHODS The CC mice model were established and the mice were randomly divided into 5 groups,including the control group,capecitabine group,the low-dose,mediumdose and high-dose groups of ISAP,with 8 mice in each group,respectively.After 2 weeks of intervention,the body weight and tumor inhibition rate of mice were observed,and the expression of RAS,ERK,phosphorylated ERK(p-ERK),C-MYC and matrix metalloproteinase 2(MMP2)proteins in the tissues of tumors were detected.RESULTS Compared with the control group,the differences of body weight before and after treatment was much smaller in the groups of ISAP,with the smallest difference in the high-dose group of ISAP,while the capecitabine group had the greatest difference,indicating ISAP had a significant inhibiting effect on the growth of transplanted tumor in mice.The expression of RAS protein was decreased in the low-and medium-dose groups of ISAP,and the change of p-ERK was significant in the medium-and high-dose groups of ISAP.MMP2 protein expression was significantly decreased in both the low-dose and medium-dose groups of ISAP.There were no significant changes in ERK in the ISAP group compared to the capecitabine group,while RAS,MMP2,and C-MYC protein expression were reduced in the ISAP group.The expression level of C-MYC protein decreased after treated with ISAP,and the decrease was the most significant in the medium-dose group of ISAP.CONCLUSION ISAP has a potential inhibiting effect on transplanted tumor in mice,and could maintain the general conditions,physical strength and body weight of mice.The expression levels of RAS,p-ERK,MMP2 and c-myc were also decreased to a certain extent.By inhibiting the expression of upstream proteins,the expression levels of downstream proteins in ERK/MAPK signaling pathway were significantly decreased.Therefore,it can be concluded that ISAP may exert an anti-tumor effect by blocking the ERK/MAPK signaling pathway and inhibiting the expression of MMP2 and c-myc proteins. 展开更多
关键词 Colon cancer Invigorating-spleen and anticancer formula Extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway Mice model C-MYC
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Experimental Procedure and Hardening Model to Consider Forming and Baking Effects in Simulation
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作者 Jiho Lim Haea Lee Jisik Choi 《World Journal of Mechanics》 2024年第7期143-168,共26页
This paper investigated an experimental method for bake hardening properties, a technique for deriving the true stress-strain curves after reaching the maximum load, and a constitutive equation considering both work h... This paper investigated an experimental method for bake hardening properties, a technique for deriving the true stress-strain curves after reaching the maximum load, and a constitutive equation considering both work hardening and bake hardening in order to apply the work hardening occurring in the forming process of parts and the bake hardening induced in the baking process to an automotive crash simulation. A general bake hardening test is that a pre-tensioned specimen is baked and then the same specimen is tensioned again without any further treatment. For a bake hardening test of automotive steel with a tensile strength of 1.2 GPa or more, fractures often occur in curvature section outside, an extensometer due to the difference in the material strength caused by non-uniform bake hardening. This causes a problem in that the bake hardening properties cannot be obtained. In this paper, to prevent curvature fracture, tensile specimens were re-machined in the uniformly deformed region of large specimens subjected to pre-strain, and the re-machined specimens with uniform strength in all regions were re-tensioned. In the bake hardening test of ultra-high strength steels with a tensile strength of 1 GPa or more, shear band fractures occur when the pre-strain is large. This makes it impossible to obtain a true stress-strain curve because there is no uniformly deformed region under a tensile test. To overcome this problem, a new method to calculate the true stress-strain curve by comparing experimental results and the load calculated by the local strain obtained from digital images was developed. This method can be applied not only where shear band deformation occurs, but also in necking deformation, and true stress-strain curves for strains up to 2 - 3 times the uniform elongation can be obtained. A new constitutive equation was developed since an appropriate hardening model is required to simultaneously apply the work hardening and the bake hardening to the simulation. For the newly developed model, the user material subroutine of LS-Dyna was configured, and the simulation was performed on the single hat specimens with pre-strain. When both work hardening and bake hardening were considered, there was a significant increase in absorbed energy compared to when only work hardening was considered. This means that both work hardening and bake hardening should be considered in the car crash simulations to enhance the accuracy of the simulation. 展开更多
关键词 Bake Hardening Hardening model Digital Image Correlation (DIC) Inverse Method Ultra High Strength Steel (UHSS)
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Three Subjects and Seven Duties Model:Empowering Informatization Teaching Ability of Pre-Service Teachers
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作者 Jingjuan Shu Dongqi Xu 《Journal of Contemporary Educational Research》 2024年第1期13-24,共12页
By constructing a model,this study seeks to provide suggestions for strengthening pre-service teachers’informatization teaching ability.It aims to answer the following research questions:(1)What do the pre-service te... By constructing a model,this study seeks to provide suggestions for strengthening pre-service teachers’informatization teaching ability.It aims to answer the following research questions:(1)What do the pre-service teachers know about informatization instruction?What is their level of informatization teaching ability?(2)What factors influence pre-service teachers’ability to deliver informatization instruction?How to overcome the obstacles?The inquiry focuses on the theoretical exploration of informatization teaching ability,questionnaire,and interview analysis on the current condition and improvement of pre-service teachers’informatization teaching ability.The data from the questionnaire and interview of the pre-service teachers were evaluated from three dimensions:awareness and attitude towards informatization teaching,knowledge of informatization teaching,and the ability to apply informatization teaching skills innovatively and comprehensively.The 3S-7D(Three Subjects and Seven Duties)model consisting of three subjects and the seven duties that go with them is established.The three subjects include pre-service teachers,teacher educators,and higher education schools.The seven duties involve pre-service teachers demonstrating learning motivation,cross-discipline thinking,and information and communications technology mastery;teacher educators actively constructing informatization teaching practice and formative assessment;and higher education schools providing adequate hardware and software equipment while offering cooperative opportunities with primary and junior schools through institutionalization. 展开更多
关键词 Pre-service teachers Informatization teaching ability 3S-7D model
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Time-Varying Mesh Stiffness Calculation and Dynamic Modeling of Spiral Bevel Gear with Spalling Defects
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作者 Keyuan Li Baijie Qiao +2 位作者 Heng Fang Xiuyue Yang Xuefeng Chen 《Journal of Dynamics, Monitoring and Diagnostics》 2024年第2期143-155,共13页
Time-varying mesh stiffness(TVMS)is a vital internal excitation source for the spiral bevel gear(SBG)transmission system.Spalling defect often causes decrease in gear mesh stiffness and changes the dynamic characteris... Time-varying mesh stiffness(TVMS)is a vital internal excitation source for the spiral bevel gear(SBG)transmission system.Spalling defect often causes decrease in gear mesh stiffness and changes the dynamic characteristics of the gear system,which further increases noise and vibration.This paper aims to calculate the TVMS and establish dynamic model of SBG with spalling defect.In this study,a novel analytical model based on slice method is proposed to calculate the TVMS of SBG considering spalling defect.Subsequently,the influence of spalling defect on the TVMS is studied through a numerical simulation,and the proposed analytical model is verified by a finite element model.Besides,an 8-degrees-of-freedom dynamic model is established for SBG transmission system.Incorporating the spalling defect into TVMS,the dynamic responses of spalled SBG are analyzed.The numerical results indicate that spalling defect would cause periodic impact in time domain.Finally,an experiment is designed to verify the proposed dynamic model.The experimental results show that the spalling defect makes the response characterized by periodic impact with the rotating frequency of spalled pinion. 展开更多
关键词 dynamic modeling slice method SPALLING spiral bevel gear time-varying mesh stiffness(TVMS)
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Effects of Continuous Precision Nursing Model on Knowledge, Attitudes, and Practices (KAP) Behavior and Cardiac Function in Patients after Percutaneous Coronary Angiography and Stent Implantation
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作者 Cuiying Han 《Journal of Clinical and Nursing Research》 2024年第3期1-6,共6页
Objective:To explore the impact of a continuous precision nursing model on patients’Knowledge,Attitudes,and Practices(KAP)and cardiac function during the nursing process of patients undergoing percutaneous coronary a... Objective:To explore the impact of a continuous precision nursing model on patients’Knowledge,Attitudes,and Practices(KAP)and cardiac function during the nursing process of patients undergoing percutaneous coronary angiography and stent implantation.Methods:Ninety patients who underwent percutaneous coronary angiography and stent implantation in our hospital from April 2022 to April 2023 were selected and randomly divided into the control group(45 cases),in which routine nursing support was carried out during the treatment process,and the observation group(45 cases),in which continuous precision nursing model was carried out during the treatment process.Comparisons were made between the two groups of patients on their KAP,cardiac function,and quality of life during recovery.Results:There was no difference in the left ventricular ejection fraction(LVEF),cardiac output(CO),and cardiac index(CI)levels before intervention.After the intervention,the levels of cardiac function in the observation group were higher than those of the control group(P<0.05).There was no difference in the Exercise of Self-Care Agency(ESCA)self-care ability scale scores before the intervention.After the intervention,the observation group had higher ESCA scores than the control group(P<0.05).Conclusion:Implementation of a continuous precision nursing model in the care of patients undergoing percutaneous coronary angiography and stent implantation improved the patient’s cardiac function,and KAP,and promoted recovery. 展开更多
关键词 Continuous precision nursing model Percutaneous coronary angiography Stent implantation Knowledge attitudes and practices(KAP) Cardiac function
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Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence 被引量:1
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作者 Jiazhen ZHAO Shengping HE +2 位作者 Ke FAN Huijun WANG Fei LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1465-1482,共18页
Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Ar... Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained). 展开更多
关键词 wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence
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