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Understanding and controlling the variables for stromal vascular fraction therapy 被引量:1
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作者 Naveen Jeyaraman Sandeep Shrivastava +3 位作者 VR Ravi Arulkumar Nallakumarasamy Aditya Pundkar Madhan Jeyaraman 《World Journal of Stem Cells》 SCIE 2024年第8期784-798,共15页
In regenerative medicine,the isolation of mesenchymal stromal cells(MSCs)from the adipose tissue’s stromal vascular fraction(SVF)is a critical area of study.Our review meticulously examines the isolation process of M... In regenerative medicine,the isolation of mesenchymal stromal cells(MSCs)from the adipose tissue’s stromal vascular fraction(SVF)is a critical area of study.Our review meticulously examines the isolation process of MSCs,starting with the extraction of adipose tissue.The choice of liposuction technique,anatomical site,and immediate processing are essential to maintain cell functionality.We delve into the intricacies of enzymatic digestion,emphasizing the fine-tuning of enzyme concentrations to maximize cell yield while preventing harm.The review then outlines the filtration and centrifugation techniques necessary for isolating a purified SVF,alongside cell viability assessments like flow cytometry,which are vital for confirming the efficacy of the isolated MSCs.We discuss the advantages and drawbacks of using autologous vs allogeneic SVF sources,touching upon immunocompatibility and logistical considerations,as well as the variability inherent in donor-derived cells.Anesthesia choices,the selection between hypo-dermic needles vs liposuction cannulas,and the role of adipose tissue lysers in achieving cellular dissociation are evaluated for their impact on SVF isolation.Centrifugation protocols are also analyzed for their part in ensuring the integrity of the SVF.The necessity for standardized MSC isolation protocols is highlighted,promoting reproducibility and successful clinical application.We encourage ongoing research to deepen the understanding of MSC biology and therapeutic action,aiming to further the field of regenerative medicine.The review concludes with a call for rigorous research,interdisciplinary collaboration,and strict adherence to ethical and regulatory standards to safeguard patient safety and optimize treatment outcomes with MSCs. 展开更多
关键词 Mesenchymal stromal cells Stromal vascular fraction Adipose tissue Autologous stromal vascular fraction Stromal vascular fraction isolation
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Analytical solutions fractional order partial differential equations arising in fluid dynamics
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作者 Sidheswar Behera Jasvinder Singh Pal Virdi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期458-468,共11页
This article describes the solution procedure of the fractional Pade-Ⅱ equation and generalized Zakharov equation(GSEs)using the sine-cosine method.Pade-Ⅱ is an important nonlinear wave equation modeling unidirectio... This article describes the solution procedure of the fractional Pade-Ⅱ equation and generalized Zakharov equation(GSEs)using the sine-cosine method.Pade-Ⅱ is an important nonlinear wave equation modeling unidirectional propagation of long-wave in dispersive media and GSEs are used to model the interaction between one-dimensional high,and low-frequency waves.Classes of trigonometric and hyperbolic function solutions in fractional calculus are discussed.Graphical simulations of the numerical solutions are flaunted by MATLAB. 展开更多
关键词 the sine-cosine method He's fractional derivative analytical solution fractional Pade-Ⅱequation fractional generalized Zakharov equation
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图的Fractional边全控制 被引量:1
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作者 徐保根 赵丽鑫 邹妍 《华东交通大学学报》 2015年第6期106-109,共4页
设G=(V,E)是一个无孤立边的图,一个实值函数f:E(G)→[0,1]若对所有的边e∈E(G),均有Σe∈N(e)f(e)≥1成立,则称f为图G的一个F ractional边全控制函数。图G的Fractional边全控制数定义为γft′(G)=min{Σe∈Ef(e)|f为图G的一个Fractiona... 设G=(V,E)是一个无孤立边的图,一个实值函数f:E(G)→[0,1]若对所有的边e∈E(G),均有Σe∈N(e)f(e)≥1成立,则称f为图G的一个F ractional边全控制函数。图G的Fractional边全控制数定义为γft′(G)=min{Σe∈Ef(e)|f为图G的一个Fractional边全控制函数}。确定了一般图的F ractional边全控制数若干界限,同时也研究了几类特殊图F ractional边全控制问题,给出了一些特殊图的Fractional边全控制数。 展开更多
关键词 fractional边全控制函数 fractional边全控制数 fractional边全包装函数 fractional边全包装数
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A unified fractional flow framework for predicting the liquid holdup in two-phase pipe flows
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作者 Fuqiao Bai Yingda Lu Mukul M.Sharma 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2614-2624,共11页
Two-phase pipe flow occurs frequently in oil&gas industry,nuclear power plants,and CCUS.Reliable calculations of gas void fraction(or liquid holdup)play a central role in two-phase pipe flow models.In this paper w... Two-phase pipe flow occurs frequently in oil&gas industry,nuclear power plants,and CCUS.Reliable calculations of gas void fraction(or liquid holdup)play a central role in two-phase pipe flow models.In this paper we apply the fractional flow theory to multiphase flow in pipes and present a unified modeling framework for predicting the fluid phase volume fractions over a broad range of pipe flow conditions.Compared to existing methods and correlations,this new framework provides a simple,approximate,and efficient way to estimate the phase volume fraction in two-phase pipe flow without invoking flow patterns.Notably,existing correlations for estimating phase volume fraction can be transformed and expressed under this modeling framework.Different fractional flow models are applicable to different flow conditions,and they demonstrate good agreement against experimental data within 5%errors when compared with an experimental database comprising of 2754 data groups from 14literature sources,covering various pipe geometries,flow patterns,fluid properties and flow inclinations.The gas void fraction predicted by the framework developed in this work can be used as inputs to reliably model the hydraulic and thermal behaviors of two-phase pipe flows. 展开更多
关键词 Pipe fractional flow Liquid holdup Multiphase pipe flow Gas void fraction
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A new study and modeling of COVID-19 disease through fractional models:A comparative paradigm
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作者 Muhammad Asad Ullah Nauman Raza 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期674-699,共26页
In this research,novel epidemic models based on fractional calculus are developed by utilizing the Caputo and Atangana-Baleanu(AB)derivatives.These models integrate vaccination effects,additional safety measures,home ... In this research,novel epidemic models based on fractional calculus are developed by utilizing the Caputo and Atangana-Baleanu(AB)derivatives.These models integrate vaccination effects,additional safety measures,home and hospital isolation,and treatment options.Fractional models are particularly significant as they provide a more comprehensive understanding of epidemic diseases and can account for non-locality and memory effects.Equilibrium points of the model are calculated,including the disease-free and endemic equilibrium points,and the basic reproduction number R0 is computed using the next-generation matrix approach.Results indicate that the epidemic becomes endemic when R0 is greater than unity,and it goes extinct when it is less than unity.The positiveness and boundedness of the solutions of model are verified.The Routh-Hurwitz technique is utilized to analyze the local stability of equilibrium points.The Lyapunov function and the LaSalle’s principle are used to demonstrate the global stability of equilibrium points.Numerical schemes are proposed,and their validity is established by comparing them to the fourth-order Runge-Kutta(RK4)method.Numerical simulations are performed using the Adams-Bashforth-Moulton predictor-corrector algorithm for the Caputo time-fractional derivative and the Toufik-Atangana numerical technique for the AB time-fractional derivative.The study looks at how the quarantine policy affected different human population groups.On the basis of these findings,a strict quarantine policy voluntarily implemented by an informed human population can help reduce the pandemic’s spread.Additionally,vaccination efforts become a crucial tool in the fight against diseases.We can greatly lower the number of susceptible people and develop a shield of immunity in the population by guaranteeing common access to vaccinations and boosting vaccination awareness.Moreover,the graphical representations of the fractional models are also developed. 展开更多
关键词 Atangana-Baleanu fractional derivative Caputo fractional derivative Tou k-Atangana numeri-cal scheme Adams-Bashforth-Moulton predictor-corrector Reproduction number R_(0)
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Binding Number and Fractional k-Factors of Graphs
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作者 Renying Chang 《Journal of Applied Mathematics and Physics》 2024年第7期2594-2600,共7页
In this paper, we consider the relationship between the binding number and the existence of fractional k-factors of graphs. The binding number of G is defined by Woodall as bind(G)=min{ | NG(X) || X |:∅≠X⊆V(G) }. It ... In this paper, we consider the relationship between the binding number and the existence of fractional k-factors of graphs. The binding number of G is defined by Woodall as bind(G)=min{ | NG(X) || X |:∅≠X⊆V(G) }. It is proved that a graph G has a fractional 1-factor if bind(G)≥1and has a fractional k-factor if bind(G)≥k−1k. Furthermore, it is showed that both results are best possible in some sense. 展开更多
关键词 Binding Number fractional k-Factor fractional Matching Independent Set Covering Set
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Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment
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作者 Ntombela N. Lethukuthula Mathuthu Manny Nyathi Mpumelelo 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第3期41-52,共12页
The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatme... The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery. 展开更多
关键词 Breast Cancer Deep Inspiration Breath Hold Hypo-fractionation Inter-fraction
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Multiple Solutions for a Class of Singular Boundary Value Problems of Hadamard Fractional Differential Systems with p-Laplacian Operator
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作者 Chen Wang Yansheng Liu 《Journal of Applied Mathematics and Physics》 2024年第9期3114-3134,共21页
This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the ... This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the sake of overcoming the singularity, sequences of approximate solutions to the boundary value problem are obtained by applying the fixed point index theory on the cone. Next, it is demonstrated that these sequences of approximate solutions are uniformly bounded and equicontinuous. The main results are then established through the Ascoli-Arzelà theorem. Ultimately, an instance is worked out to test and verify the validity of the main results. 展开更多
关键词 Multiple Solutions Fixed Point Index Theory Nonlinear fractional Differential Systems Hadamard fractional Derivative
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Legendre-Weighted Residual Methods for System of Fractional Order Differential Equations
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作者 Umme Ruman Md. Shafiqul Islam 《Journal of Applied Mathematics and Physics》 2024年第9期3163-3184,共22页
The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and ... The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and Collocation methods are included for solving fractional order differential equations, which is broadened to acquire the approximate solutions of fractional order systems with differentiable polynomials, namely Legendre polynomials, as basis functions. The algorithm of the residual formulations of matrix form can be coded efficiently. The interpretation of Caputo fractional derivatives is employed here. We have demonstrated these methods numerically through a few examples of linear and nonlinear BVPs. The results in absolute errors show that the present method efficiently finds the numerical solutions of fractional order systems of differential equations. 展开更多
关键词 fractional Differential Equations System of fractional Order BVPs Weighted Residual Methods Modified Legendre Polynomials
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Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths 被引量:3
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作者 Zhi Zheng Hongyu Xu +3 位作者 Kai Zhang Guangliang Feng Qiang Zhang Yufei Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期117-136,共20页
Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensiona... Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing disasters.Therefore,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is proposed.True triaxial static compression and intermittent disturbance tests are carried out on monzogabbro.The effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture mechanism.Rapid increases in microseismic parameters during rock loading can be precursors for intermittent rock disturbance.Based on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental results.The sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are predicted.This study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads. 展开更多
关键词 True triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect fractional mechanical model
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Fractional differential equations of motion in terms of combined Riemann-Liouville derivatives 被引量:15
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作者 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期302-306,共5页
In this paper, we focus on studying the fractional variational principle and the differential equations of motion for a fractional mechanical system. A combined Riemann-Liouville fractional derivative operator is defi... In this paper, we focus on studying the fractional variational principle and the differential equations of motion for a fractional mechanical system. A combined Riemann-Liouville fractional derivative operator is defined, and a fractional Hamilton principle under this definition is established. The fractional Lagrange equations and the fractional Hamilton canonical equations are derived from the fractional Hamilton principle. A number of special cases are given, showing the universality of our conclusions. At the end of the paper, an example is given to illustrate the application of the results. 展开更多
关键词 fractional Hamilton principle fractional Lagrange equation fractional Hamilton canon-ical equation combined Riemann-Liouville fractional derivative
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Efficacy of stromal vascular fraction for knee osteoarthritis:A prospective,single-centre,non-randomized study with 2 years follow-up 被引量:2
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作者 Madhan Jeyaraman Naveen Jeyaraman +4 位作者 Tarun Jayakumar Swaminathan Ramasubramanian Rajni Ranjan Saurabh Kumar Jha Ashim Gupta 《World Journal of Orthopedics》 2024年第5期457-468,共12页
BACKGROUND Current osteoarthritis(OA)treatments focus on symptom relief without addressing the underlying disease process.In regenerative medicine,current treatments have limitations.In regenerative medicine,more rese... BACKGROUND Current osteoarthritis(OA)treatments focus on symptom relief without addressing the underlying disease process.In regenerative medicine,current treatments have limitations.In regenerative medicine,more research is needed for intra-articular stromal vascular fraction(SVF)injections in OA,including dosage optimization,long-term efficacy,safety,comparisons with other treatments,and mechanism exploration.AIM To compare the efficacy of intra-articular SVF with corticosteroid(ICS)injections in patients with primary knee OA.METHODS The study included 50 patients with Kellgren-Lawrence grades II and III OA.Patients were randomly assigned(1:1)to receive either a single intra-articular SVF injection(group A)or a single intra-articular ICS(triamcinolone)(group B)injection.Patients were followed up at 1,3,6,12,and 24 months.Visual analog score(VAS)and International Knee Documentation Committee(IKDC)scores were administered before the procedure and at all followups.The safety of SVF in terms of adverse and severe adverse events was recorded.Statistical analysis was performed with SPSS Version 26.0,IBM Corp,Chicago,IL,United States.RESULTS Both groups had similar demographics and baseline clinical characteristics.Follow-up showed minor patient loss,resulting in 23 and 24 in groups A and B respectively.Group A experienced a notable reduction in pain,with VAS scores decreasing from 7.7 to 2.4 over 24 months,compared to a minor reduction from 7.8 to 6.2 in Group B.This difference in pain reduction in group A was statistically significant from the third month onwards.Additionally,Group A showed significant improvements in knee functionality,with IKDC scores rising from 33.4 to 83.10,whereas Group B saw a modest increase from 36.7 to 45.16.The improvement in Group A was statistically significant from 6 months and maintained through 24 months.CONCLUSION Our study demonstrated that intra-articular administration of SVF can lead to reduced pain and improved knee function in patients with primary knee OA.More adequately powered,multi-center,double-blinded,randomised clinical trials with longer follow-ups are needed to further establish safety and justify its clinical use. 展开更多
关键词 Knee osteoarthritis Adipose tissue Stromal vascular fraction Regenerative medicine Orthobiologics
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Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population:a two-sample bidirectional Mendelian randomization study 被引量:1
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作者 Xiong-Bin MA Yong-Ming LIU +1 位作者 Yan-Lin LV Lin QIAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期64-80,共17页
BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated th... BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.METHODS Transferrin saturation(TSAT),total iron binding capacity(TIBC),and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies.Individuals without myocardial infarction history,HF,or LV ejection fraction(LVEF)<50%(n=16,923)in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset.The dataset included LV end-diastolic volume,LV endsystolic volume,LV mass(LVM),and LVM-to-end-diastolic volume ratio(LVMVR).We used a two-sample bidirectional MR study with inverse variance weighting(IVW)as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.RESULTS In the IVW analysis,one standard deviation(SD)increased in TSAT significantly correlated with decreased LVMVR(β=-0.1365;95%confidence interval[CI]:-0.2092 to-0.0638;P=0.0002)after Bonferroni adjustment.Conversely,no significant relationships were observed between other iron and LV parameters.After Bonferroni correction,reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT(β=-0.0699;95%CI:-0.1087 to-0.0311;P=0.0004).No heterogeneity or pleiotropic effects evidence was observed in the analysis.CONCLUSIONS We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population. 展开更多
关键词 fraction function PARAMETERS
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum Ethyl acetate fraction ZEBRAFISH
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Effects of long-term partial substitution of inorganic fertilizer with pig manure and/or straw on nitrogen fractions and microbiological properties in greenhouse vegetable soils 被引量:1
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作者 Shuo Yuan Ruonan Li +5 位作者 Yinjie Zhang Hao'an Luan Jiwei Tang Liying Wang Hongjie Ji Shaowen Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2083-2098,共16页
Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management practice.An 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of differen... Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management practice.An 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of different partial substitution treatments on crop yields and the transformation of nitrogen fractions in greenhouse vegetable soil.Four treatments with equal N,P_(2)O_(5),and K_(2)O inputs were selected,including complete inorganic fertilizer N(CN),50%inorganic fertilizer N plus 50%pig manure N(CPN),50%inorganic fertilizer N plus 25%pig manure N and 25%corn straw N(CPSN),and 50%inorganic fertilizer N plus 50%corn straw N(CSN).Organic substitution treatments tended to increase crop yields since the 6th cropping period compared to the CN treatment.From the 8th to the 22nd cropping periods,the highest yields were observed in the CPSN treatment where yields were 7.5-11.1%greater than in CN treatment.After 11-year fertilization,compared to CN,organic substitution treatments significantly increased the concentrations of NO_(3)^(-)-N,NH_(4)^(+)-N,acid hydrolysis ammonium-N(AHAN),amino acid-N(AAN),amino sugar-N(ASN),and acid hydrolysis unknown-N(AHUN)in soil by 45.0-69.4,32.8-58.1,49.3-66.6,62.0-69.5,34.5-100.3,and 109.2-172.9%,respectively.Redundancy analysis indicated that soil C/N and OC concentration significantly affected the distribution of N fractions.The highest concentrations of NO_(3)^(-)-N,AHAN,AAN,AHUN were found in the CPSN treatment.Organic substitution treatments increased the activities ofβ-glucosidase,β-cellobiosidase,N-acetyl-glucosamidase,L-aminopeptidase,and phosphatase in the soil.Organic substitution treatments reduced vector length and increased vector angle,indicating alleviation of constraints of C and N on soil microorganisms.Organic substitution treatments increased the total concentrations of phospholipid fatty acids(PLFAs)in the soil by 109.9-205.3%,and increased the relative abundance of G^(+)bacteria and fungi taxa,but decreased the relative abundance of G-bacteria,total bacteria,and actinomycetes.Overall,long-term organic substitution management increased soil OC concentration,C/N,and the microbial population,the latter in turn positively influenced soil enzyme activity.Enhanced microorganism numbers and enzyme activity enhanced soil N sequestration by transforming inorganic N to acid hydrolysis-N(AHN),and enhanced soil N supply capacity by activating non-acid hydrolysis-N(NAHN)to AHN,thus improving vegetable yield.Application of inorganic fertilizer,manure,and straw was a more effective fertilization model for achieving sustainable greenhouse vegetable production than application of inorganic fertilizer alone. 展开更多
关键词 organic substitution management greenhouse vegetable production N fractions microbial community composition extracellular enzyme activity enzyme stoichiometry coefficients
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Model reduction of fractional impedance spectra for time–frequency analysis of batteries, fuel cells, and supercapacitors 被引量:1
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作者 Weiheng Li Qiu-An Huang +6 位作者 Yuxuan Bai Jia Wang Linlin Wang Yuyu Liu Yufeng Zhao Xifei Li Jiujun Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期108-141,共34页
Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlatio... Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices. 展开更多
关键词 battery fuel cell supercapacitor fractional impedance spectroscopy model reduction time-frequency analysis
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European Option Pricing under a Class of Fractional Market 被引量:4
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作者 费为银 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期732-737,共6页
In order to price European contingent claim in a class of fractional Black-Scholes market, where the prices of assets follow a Wick-Ito stochastic differential equation driven by the fractional Brownian motion and mar... In order to price European contingent claim in a class of fractional Black-Scholes market, where the prices of assets follow a Wick-Ito stochastic differential equation driven by the fractional Brownian motion and market coefficients are deterministic functions, the pricing formula of European call option was explicitly derived by the method of the stochastic calculus of tile fractional Brownian motion. A result about fractional Clark derivative was also obtained. 展开更多
关键词 fractional Brownian motion Wick-Ito stochasticintegral fractional It( formula ~ Girsanov thoerem forfractional Brownian motion fractional Clark-Oconetheorem option pricing
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External stability of fractional-order control systems 被引量:1
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作者 曾庆山 曹广益 朱新坚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第1期32-36,共5页
The external stability of fractional-order continuous linear control systems described by both fractional-order state space representation and fractional-order transfer function is mainly investigated in this paper. I... The external stability of fractional-order continuous linear control systems described by both fractional-order state space representation and fractional-order transfer function is mainly investigated in this paper. In terms of Lyapunov’s stability theory and the stability analysis of the integer-order linear control systems, the definitions of external stability for fractional-order control systems are presented. By using the theorems of the Mittag-Leffler function in two parameters, the necessary and sufficient conditions of external stability are directly derived. The illustrative examples and simulation results are also given. 展开更多
关键词 fractional calculus fractional-order system fractional-order state space representation fractional-order transfer function external stability
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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction
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作者 Estel Viñolas-Vergés Jordi Ribas-Maynou +4 位作者 Isabel Barranco Camila Peres Rubio Sergi Bonet Jordi Roca Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期171-181,共11页
Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separa... Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction. 展开更多
关键词 CHROMATIN Condensation DNA integrity Ejaculate fractions PIG Protamination SPERM
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A novel variable-order fractional chaotic map and its dynamics
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作者 唐周青 贺少波 +3 位作者 王会海 孙克辉 姚昭 吴先明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期281-290,共10页
In recent years,fractional-order chaotic maps have been paid more attention in publications because of the memory effect.This paper presents a novel variable-order fractional sine map(VFSM)based on the discrete fracti... In recent years,fractional-order chaotic maps have been paid more attention in publications because of the memory effect.This paper presents a novel variable-order fractional sine map(VFSM)based on the discrete fractional calculus.Specially,the order is defined as an iterative function that incorporates the current state of the system.By analyzing phase diagrams,time sequences,bifurcations,Lyapunov exponents and fuzzy entropy complexity,the dynamics of the proposed map are investigated comparing with the constant-order fractional sine map.The results reveal that the variable order has a good effect on improving the chaotic performance,and it enlarges the range of available parameter values as well as reduces non-chaotic windows.Multiple coexisting attractors also enrich the dynamics of VFSM and prove its sensitivity to initial values.Moreover,the sequence generated by the proposed map passes the statistical test for pseudorandom number and shows strong robustness to parameter estimation,which proves the potential applications in the field of information security. 展开更多
关键词 CHAOS fractional difference variable order MULTISTABILITY COMPLEXITY
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