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The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system

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Oncology Research 2024年第3期32卷 477-487页

作者： SAMANEH MOSTAFAVI ZUHAIR mohammad HASSAN Department of Immunology Faculty of Medical SciencesTarbiat Modares UniversityTehranIran

Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy *** hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and *** order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal *** created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our ***,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate *** results were validated using the monoculture of each group separately as a *** this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both ***,MCT4 and lactate stayed high after treatment with *** conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal ***,however,may change this state and affect fibroblasts'acquired ***,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer.

关键词： Caveolin 1 Lactic acid Metformin NIH 3T3 cells Neoplasms

Myelopathy as a Presentation of Cervical Spine Metastasis: A Case Report

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Open Journal of Modern Neurosurgery 2024年第1期14卷 64-71页

作者： Ramin Shayan-Moghadam Mosayeb Soleymani Hassan Zolghadr mohammad Hossein Nabian Saeed reza Mehrpour Department of Orthopedic and Trauma Surgery Shariati Hospital Tehran University of Medical Sciences Tehran Iran Center for Orthopedic Trans-Deciplinary Applied Research Tehran University of Medical Sciences Tehran Iran

Cervical myelopathy is a consequence of spinal cord compression in the cervical spine. Degenerative cervical spondylosis, osteophytes, discosteophyte complex, degenerative spondylolisthesis and hypertrophy of ligamentum flavum are the main etiologies of cervical myelopathy. Metastasis to cervical spine could be a rare cause of cervical myelopathy. The present study is a case report;presented a 36-year-old male with severe pain in cervical region, gait disability and impairment in sensory and motor function of upper left extremity. The patient had a history of thyroidectomy and cervical lymph node dissection due to follicular thyroid carcinoma (FTC) with improper follow-ups. He was diagnosed with metastatic cervical myelopathy and underwent surgical treatment. Cervical myelopathy due to metastasis is a rare condition and only few cases have been reported so far. So myelopathies can be a complication of metastatic cancers, and it should be considered by health professionals.

关键词： Myelopathy Metastasis Thyroid Cancer

Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： Amir mohammad Zamani Ashkan Moslemi Kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

Transient Stability Analysis of Grid-connected Converters in Wind Turbine Systems Based on Linear Lyapunov Function and Reverse-time Trajectory

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 782-790页

作者： mohammad Kazem Bakhshizadeh Sujay Ghosh Guangya Yang Łukasz Kocewiak Ørsted Wind Power A/S Nesa Allé12820Denmark Technical University of Denmark Anker Engelunds Vej 12800Denmark

As the proportion of converter-interfaced renewable energy resources in the power system is increasing,the strength of the power grid at the connection point of wind turbine generators(WTGs)is gradually *** research has shown that when connected with the weak grid,the stability of the traditional grid-following controlled converters will deteriorate,and they are prone to unstable phenomena such as *** to the limitations of linear analysis that cannot sufficiently capture the stability phenomena,transient stability must be *** far,standalone time-domain simulations or analytical Lyapunov stability criteria have been used to investigate transient ***,the time-domain simulations have proven to be computationally too heavy,while analytical methods are difficult to formulate for larger systems,require many modelling assumptions,and are often conservative in estimating the stability *** paper proposes and demonstrates an innovative approach to estimating the transient stability boundary via combining the linear Lyapunov function and the reverse-time trajectory *** proposed methodology eliminates the need of time-consuming simulations and the conservative nature of Lyapunov *** study brings out the clear distinction between the stability boundaries with different post-fault active current ramp rate *** the same time,it provides a new perspective on critical clearing time for wind turbine *** stability boundary is verified using time-domain simulation studies.

关键词： Lyapunov direct method non-autonomous system phase-locked loop(PLL) time trajectory reversal transient stability assessment wind turbine converter system

Enhanced adaptive nonlinear extended state observer for pure feedback systems with matched and mismatched disturbances

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Control Theory and Technology 2024年第2期22卷 254-268页

作者： Mahtab Delpasand mohammad Farrokhi School of Electrical Engineering Iran University of Science and TechnologyTehran16846-13114Iran Center of Excellence for Modelling and Control of Complex Systems Iran University of Science and TechnologyTehran16846-13114Iran

In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature.

关键词： Nonlinear extended state observer Enhanced adaptive extended state observer Adaptation law Multiple-channel disturbances Inverted pendulum system Time-varying gain

Longitudinal vibration characteristics of a tapered pipe pile considering the vertical support of surrounding soil and construction disturbance

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 51-63页

作者： Li Zhenya Pan Yunchao He Xianbin Lv Chong mohammad Towhid Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Geotechnical Research Institute Hohai UniversityNanjing 210098China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China

This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction ***,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile *** surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction ***,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost *** displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent ***,the displacement impedance at the pile head is obtained based on the impedance function transfer ***,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile.

关键词： tapered pipe pile longitudinal vibration vertical support of the surrounding soil construction disturbance displacement impedance

Peer-to-Peer Trading in Distribution Systems with the Utility's Operation

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 629-638页

作者： Xuanyi Xiao Feng Wang mohammad Shahidehpour Yujia Zhai Quan Zhou Department of Electrical and Information Engineering Hunan UniversityChangshaChina Robert W.Galvin Center for Electricity Innovation Ilinois Institute of TechnologyChicagoIL60616USA

To realize a liberalized peer-to-peer (P2P) electricity market in distribution systems with network security, this paper develops a general framework for P2P trading in distribution systems with the utility's operation. The model is formulated as a bi-level programming. The utility's operation is an upper level problem, where a calculation method of network usage charges for P2P trading is also proposed. Peers' P2P trading is a lower level problem. An iterative algorithm based on analytical target cascading (ATC) is proposed to solve the model, where the interactions between utility and peers are presented. Numerical results on the IEEE 33-bus system demonstrate that the proposed method realizes a liberalized P2P market and ensures network security in distribution systems.

关键词： Distribution system peer-to-peer trading electricitymarket distributed energyresources(DERs) analytical target cascading(ATC)

Wettability modification effects on relative permeability end-points:Comparative analysis of surfactant agents for enhanced oil recovery

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Petroleum Research 2024年第2期9卷 206-218页

作者： Erfan Hosseini Negar Hosseini mohammad Sarmadivaleh Exploration Directorate National Iranian Oil Company(NIOC)TehranIran Department of Petroleum Engineering Islamic Azad University(IAU)IlamIran WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWestern AustraliaAustralia

This research examines the impact of wettability alteration on the end points of relative permeability,a crucial property of fluids and porous media that influences the displacement processes of immiscible fluids through such *** estimation of the mobility ratio for oil recovery relies on these end points,which are influenced by connate water saturation and residual oil *** investigate this relationship,carbonate rock is generally subjected to wettability alteration using surfactant agents,and core flooding is employed to determine the relative permeability before and after the *** wettability of the rock is commonly assessed through contact angle *** surfactants,TritonX-100(Tx-100)and Cedar,were tested in reducing the wettability of the porous media for *** contact angle measurements revealed that Tx-100 was more effective for this purpose than ***,the relative permeability tests indicated that both surfactants decreased residual oil saturation,but Tx-100 also improved system *** contrast,Cedar reduced residual oil saturation but increased system pressure,possibly because of its high *** results also demonstrate that injecting Tx-100 leads to a 14%increase in ultimate oil recovery compared with water injection,while Cedar injection increased the recovery factor by 5%.This difference may be attributed to the incomplete coverage of the pore wall by Cedar or its weaker chemical structure than ***,in carbonate cores,neither non-ionic surfactant enhanced oil recovery.

关键词： Wettability alteration Relative permeability Core flooding Tx-100 Cedar Contact angle

Development of anti-corrosive coating on AZ31 Mg alloy modified by MOF/LDH/PEO hybrids

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Journal of Magnesium and Alloys 2024年第2期12卷 586-607页

作者： Muhammad Ali Khan Ananda Repycha Safira mohammad Aadil Mosab Kaseem Corrosion and Electrochemistry Laboratory Department of Nanotechnology and Advanced Materials EngineeringSejong UniversitySeoul 05006Republic of Korea

The self-assembly of hybrid inorganic-organic materials on stationary platforms plays a critical role in improving their structural stability and wide *** this work,a novel two-step hydrothermal approach is proposed for synthesizing stable and advanced hybrid coatings on metal-oxide platforms through the surface modification of layered double hydroxide(LDH)films using novel metal-organic frameworks(MOFs).Initially,Mg-Al LDH nanocontainers,grown on a magnesium oxide layer produced through plasma electrolytic oxidation(PEO)of AZ31 Mg alloy substrate,were intercalated with cobalt via an oxidation route,providing the metallic coordination center for the MOF *** the subsequent step,a pioneering technique is introduced,utilizing tryptophan as the organic linker for the first time at a pH of *** self-assembly of cobalt-tryptophan complex,driven by the strong bonding between electrophilic sites of monomers and nucleophilic sites,facilitated the formation of a MOF network having a cloud-like structure on the surface of MgAl LDH's *** resulting MOF-LDH encapsulation containers demonstrate exceptional electrochemical stability when exposed to a 3.5 wt.%NaCl solution,surpassing the performance of PEO and pure LDH *** enhanced stability is attributed to the development of a dense top layer and a stable composition within the self-assembled MOF,effectively sealing flaws and preventing the infiltration of corrosive ions into the underlying metallic *** formation mechanism of MOFs on LDH galleries is investigated using density functional theory calculations.

关键词： Mg alloy Layered double hydroxide Metal-organic frameworks Corrosion DFT