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Synchronization in the Uncoupled Neuron System
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作者 张季谦 黄守芳 +2 位作者 庞四焘 汪茂胜 高升 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期9-13,共5页
Using the model of Hindmarsh Rose neurons, we study the synchronous behavior of the firing patterns in an uncoupled cell system. In this work, the membrane current Iext is selected as a controllable parameter, whose i... Using the model of Hindmarsh Rose neurons, we study the synchronous behavior of the firing patterns in an uncoupled cell system. In this work, the membrane current Iext is selected as a controllable parameter, whose initial values for all N cells are set to be near one of the bifurcation points randomly. It is found that the system will show un-synchronous state when the external stimuli is absent, otherwise, full synchrony will appear, even though without any coupling connection among these N neurons, indicating the occurrence of uncoupled synchrony. Moreover, similar behavior could also be observed when these neurons are set to be near other bifurcation points. The synchronous error is calculated for discussing this uncoupled synehrony behavior. Finally, we find that such synchrony may have some inherent relevance with the decrease of phase difference between different cells. Our results suggest that biological neuron systems may achieve an effective response to external feeble stimulus by the mode of uncoupled synchrony instead of only by the coupled scheme. 展开更多
关键词 Synchronization in the uncoupled Neuron System
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Influence of water coupling coefficient on the blasting effect of red sandstone specimens 被引量:1
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作者 Yang Li Renshu Yang +1 位作者 Yanbing Wang Dairui Fu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期148-166,共19页
This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation i... This study investigates the impact of different water coupling coefficients on the blasting effect of red sandstone.The analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting holes.Using DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and 2.00.The study examines the morphologies of the rock specimens after blasting under these different water coupling coefficients.Additionally,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock damage.CT scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the rock.Additionally,the volume fractal dimension and damage degree of the post-blasting specimens are calculated.The findings are then combined with numerical simulation to facilitate auxiliary analysis.The results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the explosion.The specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal dimensions.The simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water medium.As the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent. 展开更多
关键词 Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension
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Enhancing personalized exercise recommendation with student and exercise portraits
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作者 Wei-Wei Gao Hui-Fang Ma +2 位作者 Yan Zhao Jing Wang Quan-Hong Tian 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期91-109,共19页
The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning directions.Existing solutions gen... The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning directions.Existing solutions generally follow a collaborative filtering paradigm,while the implicit connections between students(exercises)have been largely ignored.In this study,we aim to propose an exercise recommendation paradigm that can reveal the latent connections between student-student(exercise-exercise).Specifically,a new framework was proposed,namely personalized exercise recommendation with student and exercise portraits(PERP).It consists of three sequential and interdependent modules:Collaborative student exercise graph(CSEG)construction,joint random walk,and recommendation list optimization.Technically,CSEG is created as a unified heterogeneous graph with students’response behaviors and student(exercise)relationships.Then,a joint random walk to take full advantage of the spectral properties of nearly uncoupled Markov chains is performed on CSEG,which allows for full exploration of both similar exercises that students have finished and connections between students(exercises)with similar portraits.Finally,we propose to optimize the recommendation list to obtain different exercise suggestions.After analyses of two public datasets,the results demonstrated that PERP can satisfy novelty,accuracy,and diversity. 展开更多
关键词 Educational data mining Exercise recommend Joint random walk Nearly uncoupled Markov chains Optimization Personalized learning
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Comparison between inhibitor and uncoupler for minimizing excess sludge production of an activated sludge process 被引量:1
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作者 CHEN Guowei XI Pengge +1 位作者 XU Deqian YU Hanqing 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2007年第1期63-66,共4页
In order to study the minimization of excess sludge production,the reduction in the excess sludge production in the presence of an inhibitor and uncoupler was studied in this work.The experimental results show that su... In order to study the minimization of excess sludge production,the reduction in the excess sludge production in the presence of an inhibitor and uncoupler was studied in this work.The experimental results show that such an addition could effectively reduce the production of excess sludge.With the energy uncoupling model established in this work,energy uncoupling coefficient(Eu)was used to evaluate the reduction in excess sludge production.The energy uncoupling coefficients in the presence of dinitrophenol(dNP),Zn^(2+),and Cu^(2+)was 0.75,0.46,and 0.18,respectively.The analysis demonstrated that energy spilling occurred in the presence of dNP,and that dNP was an effective uncoupler for reducing the production of excess activated sludge without affecting the microbial respiration activity. 展开更多
关键词 INHIBITOR uncoupleR minimizing excess sludge production energy uncoupling coefficient
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Nucleon-pair approximation with uncoupled representation 被引量:1
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作者 Y.Lei Y.Lu Y.M.Zhao 《Chinese Physics C》 SCIE CAS CSCD 2021年第5期129-140,共12页
In this paper,we propose an approach to nucleon-pair approximation(NPA)with m-scheme bases,in which the collective nucleon pairs are represented in terms of antisymmetric matrices,and commutations between nucleon pair... In this paper,we propose an approach to nucleon-pair approximation(NPA)with m-scheme bases,in which the collective nucleon pairs are represented in terms of antisymmetric matrices,and commutations between nucleon pairs are given using a matrix multiplication that avoids angular-momentum couplings and recouplings.Therefore the present approach significantly simplifies the NPA computation.Furthermore,it is formulated on the same footing with and without isospin. 展开更多
关键词 uncoupled representation nucleon-pair approximation FORMALISM computational efficiency
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The uncoupled microbial fed-batch fermentation optimization based on state-dependent switched system 被引量:1
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作者 Teng Niu Jingang Zhai +2 位作者 Hongchao Yin Enmin Feng Chongyang Liu 《International Journal of Biomathematics》 SCIE 2021年第4期189-210,共22页
In the actual microbial fermentation process,excessive or insufficient substrate can produce inhibitory effects on cells growth.The artificial substrate feeding rules by past experiences have great blindness to keep s... In the actual microbial fermentation process,excessive or insufficient substrate can produce inhibitory effects on cells growth.The artificial substrate feeding rules by past experiences have great blindness to keep substrate concentration in a given appropriate range.This paper considers that alkali feed depends on pH value of the solution and glycerol feed depends on glycerol concentration of the solution in the uncoupled microbial fed-hatch fermentation process,and establishes a state-dependent switched system in which the flow rates of glycerol and alkali,the number of mode switches,the mode sequence and the switching times are prior unknown.To maximize the yield of target product 1,3-Propanediol(1,3-PD),we formulate a switching optimal control problem with the flow rates of glycerol and alkali,the number of mode switches,the mode sequence and the switching times as decision variables,which is a mixed-integer dynamic programming problem.For solving the mixed-integer dynamic programming problem,the control parametrization technique,the time scaling transformation and the embedded system technology are used to obtain an approximate parameter optimization problem.By using a parallel optimization algorithm,we obtain the optimal control strategies.Under the obtained optimal control strategies,the 1,3-PD yield at the terminal time is increased significantly compared with the previous results. 展开更多
关键词 uncoupled fed-batch fermentation state-dependent switched system switching optimal control embedded system parallel optimization
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Response mechanism of platinum electrode to uncoupled ions(Ⅰ)——Response of platinum electrode to Pb^(2+),Cd^(2+),Ca^(2+) and Mg^(2+)
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作者 史生华 于书平 刘鹏 《Science China Chemistry》 SCIE EI CAS 1997年第1期37-44,共8页
The transient response mechanism of the platinum electrode to the uncoupled ions may be interpreted with the mixed phase formation (MPF) model of the transient response of precipitate-based ion-selective electrodes to... The transient response mechanism of the platinum electrode to the uncoupled ions may be interpreted with the mixed phase formation (MPF) model of the transient response of precipitate-based ion-selective electrodes to interfering tons for Kxy<<1 It is discovered that the peak height of the transient signal is related to the solubility of M(OH)2 and hydration heat of M2+ The relation between the positive peak height of transient signal of Pb2+ or Cd2+ and lgaM obey tne Nernst equation,while that of Ca2+ or Mg2+ does not.The equilibrium potential is not of Nernst response for all ions. 展开更多
关键词 PLATINUM ELECTRODE uncoupled ion TRANSIENT potential RESPONSE signal mixed phase formation model
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Uncoupled state space solution to layered poroelastic medium with anisotropic permeability and compressible pore fluid
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作者 Zhiyong AI Wenze ZENG +1 位作者 Yichong CHENG Chao WU 《Frontiers of Structural and Civil Engineering》 SCIE EI 2011年第2期171-179,共9页
This paper presents an uncoupled state space solution to three-dimensional consolidation of layered poroelastic medium with anisotropic permeability and compressible pore fluid.Starting from the basic equations of por... This paper presents an uncoupled state space solution to three-dimensional consolidation of layered poroelastic medium with anisotropic permeability and compressible pore fluid.Starting from the basic equations of poroelastic medium,and introducing intermediate variables,the state space equation usually comprising eight coupled state vectors is uncoupled into two sets of equations of six and two state vectors in the Laplace-Fourier transform domain.Combined with the continuity conditions between adjacent layers and boundary conditions,the uncoupled state space solution of a layered poroelastic medium is obtained by using the transfer matrix method.Numerical results show that the anisotropy of permeability and the compressibility of pore fluid have remarkable influence on the consolidation behavior of poroelastic medium. 展开更多
关键词 uncoupled state space solution layered poroelastic medium three-dimensional consolidation anisotropic permeability compressible pore fluid
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Mitochondrial uncoupler BAM15 inhibits artery constriction and potently activates AMPK in vascular smooth muscle cells 被引量:5
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作者 Yu Tai Lanjun Li +7 位作者 Xuan Peng Junxue Zhu Xihai Mao Nan Qin Minghui Ma Rong Huo Yunlong Bai Deli Dong 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2018年第6期909-918,共10页
Our previous studies found that mitochondrial uncouplers CCCP and niclosamide inhibited artery constriction and the mechanism involved AMPK activation in vascular smooth muscle cells. BAM15 is a novel type of mitochon... Our previous studies found that mitochondrial uncouplers CCCP and niclosamide inhibited artery constriction and the mechanism involved AMPK activation in vascular smooth muscle cells. BAM15 is a novel type of mitochondrial uncoupler. The aim of the present study is to identify the vasoactivity of BAM15 and characterize the BAM15-induced AMPK activation in vascular smooth muscle cells(A10 cells). BAM15 relaxed phenylephrine(PE)-induced constricted rat mesenteric arteries with intact and denuded endothelium. Pretreatment with BAM15 inhibited PEinduced constriction of rat mesenteric arteries with intact and denuded endothelium. BAM15, CCCP,and niclosamide had the comparable IC50 value of vasorelaxation in PE-induced constriction of rat mesenteric arteries. BAM15 was less cytotoxic in A10 cells compared with CCCP and niclosamide.BAM15 depolarized mitochondrial membrane potential, induced mitochondrial fission, increased mitochondrial ROS production, and increased mitochondrial oxygen consumption rate in A10 cells.BAM15 potently activated AMPK in A10 cells and the efficacy of BAM15 was stronger than that of CCCP, niclosamide, and AMPK positive activators metformin and AICAR. In conclusion, BAM15 activates AMPK in vascular smooth muscle cells with higher potency than that of CCCP, niclosamide and the known AMPK activators metformin and AICAR. The present work indicates that BAM15 is a potent AMPK activator. 展开更多
关键词 BAM15 MITOCHONDRIAL UNCOUPLING AMPK Smooth muscle cells AICAR Metformin
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Mitochondrial uncoupler triclosan induces vasorelaxation of rat arteries 被引量:3
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作者 Xiyue Zhang Xinzi Zhang +6 位作者 Yanqiu Zhang Mingyu Liu Jing Jin Jie Yan Xin Shen Nan Hu Deli Dong 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2017年第6期623-629,共7页
Our previous studies found that mitochondrial uncouplers induced vasodilation. Triclosan, the broad spectrum antibacterial agent, is the active ingredient in soaps and toothpastes. It was reported that triclosan induc... Our previous studies found that mitochondrial uncouplers induced vasodilation. Triclosan, the broad spectrum antibacterial agent, is the active ingredient in soaps and toothpastes. It was reported that triclosan induced mitochondrial uncoupling, so we aim to investigate the effects of triclosan on vascular function of rat mesenteric arteries and aorta. The isometric tension of rat mesenteric artery and thoracic aorta was recorded by multi-wire myograph system. The cytosolic [Ca^(2+)]_i, mitochondrial reactive oxygen species(mitoROS), and mitochondrial membrane potential of smooth muscle cells(A10 cells) were measured using laser scanning confocal microscopy. Triclosan treatment relaxed phenylephrine(PE)-and high K^(+)(KPSS)-induced constriction, and pre-treatment with triclosan inhibited PE-and KPSS-induced constriction of rat mesenteric arteries. In rat thoracic aorta, triclosan also relaxed PE-and KPSS-induced constriction. Triclosan induces vasorelaxation without involving KATPchannel activation in smooth muscle cells of arteries.Triclosan treatment increased cytosolic [Ca^(2+)]_i, mitochondrial ROS production and depolarized mitochondrial membrane potential in A10 cells. In conclusion, triclosan induces mitochondrial uncoupling in vascular smooth muscle cells and relaxes the constricted rat mesenteric arteries and aorta of rats. The present results suggest that triclosan would indicate vasodilation effect if absorbed excessively in vivo. 展开更多
关键词 TRICLOSAN Mitochondrial uncoupling Artery Smooth muscle cells VASORELAXATION
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Metabolic uncoupler,3,3’,4’,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control in a gravity-driven membrane bioreactor 被引量:2
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作者 An Ding Yingxue Zhao +5 位作者 Huu Hao Ngo Langming Bai Guibai Li Heng Liang Nanqi Ren Jun Nan 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2020年第6期53-64,共12页
The gravity-driven membrane bioreactor(MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements.However,the growing sludge not only increases membra... The gravity-driven membrane bioreactor(MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements.However,the growing sludge not only increases membrane fouling,but also augments operational complexities(sludge discharge).We added the metabolic uncoupler 3,3’,4f,5-tetrachlorosalicylanilide(TC$)to the system to deal with the mentioned issues.Based on the results,TCS addition effectively decreased sludge ATP and sludge yield(reduced by 50%).Extracellular polymeric substances(EPS;proteins and polysaccharides)decreased with the addition of TCS and were transformed into dissolved soluble microbial products(SMPs)in the bulk solution,leading to the break of sludge floes into small fragments.Permeability was increased by more than two times,reaching 60-70 L/m2/h bar when 10-30 mg/L TCS were added,because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels.Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances.Permeability decreased at high dosage(50 mg/L)due to the release of excess sludge fragments and SMP into the supernatant,with a thin but more compact fouling layer with low bioactivity developing on the membrane surface,causing higher cake layer and pore blocking resistances.Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages,with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems. 展开更多
关键词 Gravity-driven membrane(GDM) Energy uncoupling Permeability Sludge reduction Membrane fouling Fouling layer
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Numerical analysis of bending property of bi-modulus materials and a new method for measurement of tensile elastic modulus
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作者 Tianmin Wang Jianhong Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2539-2555,共17页
In nature,there are widely distributed bi-modulus materials with different deformation characteristics under compressive and tensile stress states,such as concrete,rock and ceramics.Due to the lack of constitutive mod... In nature,there are widely distributed bi-modulus materials with different deformation characteristics under compressive and tensile stress states,such as concrete,rock and ceramics.Due to the lack of constitutive model that could reasonably consider the bi-modulus property of materials,and the lack of simple and reliable measurement methods for the tensile elastic parameters of materials,scientists and engineers always neglect the effect of the bi-modulus property of materials in engineering design and numerical simulation.To solve this problem,this study utilizes the uncoupled strain-driven constitutive model proposed by Latorre and Montáns(2020)to systematically study the distributions and magnitudes of stresses and strains of bi-modulus materials in the three-point bending test through the numerical method.Furthermore,a new method to synchronously measure the tensile and compressive elastic moduli of materials through the four-point bending test is proposed.The numerical results show that the bi-modulus property of materials has a significant effect on the stress,strain and displacement in the specimen utilized in the three-point and four-point bending tests.Meanwhile,the results from the numerical tests,in which the elastic constitutive model proposed by Latorre and Montáns(2020)is utilized,also indicate that the newly proposed measurement method has a good reliability.Although the new measurement method proposed in this study can synchronously and effectively measure the tensile and compressive elastic moduli,it cannot measure the tensile and compressive Poisson’s ratios. 展开更多
关键词 Bi-modulus material uncoupled strain-driven constitutive model Three-point bending test Four-point bending test Tensile elastic modulus FssiCAS
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Uncoupling protein 2 deficiency of non-cancerous tissues inhibits the progression of pancreatic cancer in mice
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作者 Denis Revskij Jakob Runst +14 位作者 Camilla Umstätter Luise Ehlers Sarah Rohde Dietmar Zechner Manuela Bastian Brigitte Müller-Hilke Georg Fuellen Larissa Henze Hugo Murua Escobar Christian Junghanss Axel Kowald Uwe Walter Rüdiger Köhling Olaf Wolkenhauer Robert Jaster 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第2期190-199,共10页
Background: Pancreatic ductal adenocarcinoma(PDAC) is a disease of the elderly mostly because its development from preneoplastic lesions depends on the accumulation of gene mutations and epigenetic alterations over ti... Background: Pancreatic ductal adenocarcinoma(PDAC) is a disease of the elderly mostly because its development from preneoplastic lesions depends on the accumulation of gene mutations and epigenetic alterations over time. How aging of non-cancerous tissues of the host affects tumor progression, however, remains largely unknown. Methods: We took advantage of a model of accelerated aging, uncoupling protein 2-deficient( Ucp2 knockout, Ucp2 KO) mice, to investigate the growth of orthotopically transplanted Ucp2 wild-type(WT) PDAC cells(cell lines Panc02 and 6606PDA) in vivo and to study strain-dependent differences of the PDAC microenvironment. Results: Measurements of tumor weights and quantification of proliferating cells indicated a significant growth advantage of Panc02 and 6606PDA cells in WT mice compared to Ucp2 KO mice. In tumors in the knockout strain, higher levels of interferon-γ m RNA despite similar numbers of tumor-infiltrating T cells were observed. 6606PDA cells triggered a stronger stromal reaction in Ucp2 KO mice than in WT animals. Accordingly, pancreatic stellate cells from Ucp2 KO mice proliferated at a higher rate than cells of the WT strain when they were incubated with conditioned media from PDAC cells. Conclusions: Ucp2 modulates PDAC microenvironment in a way that favors tumor progression and implicates an altered stromal response as one of the underlying mechanisms. 展开更多
关键词 Pancreatic cancer Orthotopic model Uncoupling protein 2 FIBROSIS
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Ginsenoside F1 administration promotes UCP1-dependent fat browning and ameliorates obesity-associated insulin resistance
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作者 Yuhan Meng Weili Li +7 位作者 Chenxing Hu Si Chen Haiyang Li Feifei Bai Lujuan Zheng Ye Yuan Yuying Fan Yifa Zhou 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期2061-2072,共12页
Obesity-induced type 2 diabetes is mainly due to excessive free fatty acids leading to insulin resistance.Increasing thermogenesis is regarded as an effective strategy for hypolipidemia and hypoglycemia.Ginsenoside is... Obesity-induced type 2 diabetes is mainly due to excessive free fatty acids leading to insulin resistance.Increasing thermogenesis is regarded as an effective strategy for hypolipidemia and hypoglycemia.Ginsenoside is a natural active component in Panax ginseng C.A.Meyer,and some of them enhance thermogenesis.However,there are few studies on the mechanism and target of ginsenosides enhancing thermogenesis.Using thermogenic protein uncoupling protein 1(UCP1)-luciferase reporter assay,we identifi ed ginsenoside F1 as a novel UCP1 activator in the ginsenosides library.Using pull down assay and inhibitor interference,we found F1 binds toβ3-adrenergic receptors(β3-AR)to enhance UCP1 expression via cAMP/PKA/CREB pathway.We also investigated the ability of F1 on energy metabolism in obesity-induced diabetic mice,including body weight,body composition and energy expenditure.The results of proteomics showed that F1 signifi cantly up-regulated thermogenesis proteins and lipolytic proteins,but down-regulated fatty acid synthesis proteins.Ginsenoside F1 increased thermogenesis and ameliorated insulin resistance specifi cally by promoting the browning of white adipose tissue in obese mice.Additionally,ginsenoside F1 improves norepinephrine-induced insulin resistance in adipocytes and hepatocytes,and shows a stronger mitochondria respiration ability than norepinephrine.These fi ndings suggest that ginsenoside F1 is a promising lead compound in the improvement of insulin resistance. 展开更多
关键词 Ginsenoside F1 Uncoupling protein 1 β3-Adrenergic receptor White adipose tissue browning Insulin resistance
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Modulation of Respiratory Neural Drive by Physiological Loads in COVID-19 Patients with Dyspnea
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作者 Maxim Crasta Zainab Alam Shamil Lakhani 《Neuroscience & Medicine》 2023年第3期29-46,共18页
COVID-19 patients often experience dyspnea due to several factors. The underlying unique pathophysiology of dyspnea in COVID-19 is not yet fully understood, but it is believed to be related to a combination of respira... COVID-19 patients often experience dyspnea due to several factors. The underlying unique pathophysiology of dyspnea in COVID-19 is not yet fully understood, but it is believed to be related to a combination of respiratory, cardiovascular, and neuromuscular factors. Hypoxemia is considered one of the key symptoms of COVID-19. This affects the respiratory drive, which determines the rate, depth, and pattern of breathing. The relationship between increased ventilatory neural drive and abnormal gas exchange, particularly in the context of ventilation/perfusion (V/Q) mismatches and chemosensitivity, has gained significant attention following the COVID-19 pandemic. The ACE2 receptors allow viral entry into the lungs, leading to the loss of surfactant, hypoxic vasoconstriction, and intrapulmonary shunting that may result in a V/Q mismatch. Additionally, acidosis, hypercapnia, elevated 2,3-diphosphogly-cerate levels and fever may shift the oxygen diffusion curve rightward, lowering arterial oxygen saturation levels and triggering ventilatory responses. This paper examines how physio pathological factors such as altered gas diffusion, chemosensory feedback, V/Q ratios, altered compliance, arterial blood gases, and respiratory muscle dysfunction in these patients affect ventilatory drive. A review of the published literature was also conducted to determine the mechanism of dyspnea. To ensure appropriate gas exchange, individuals need to augment their minute ventilation (VE) when physiological dead space is elevated. This serves as a compensatory mechanism to counteract the effects of compromised gas exchange and keep adequate oxygenation throughout the body. The respiratory centers may experience dysregulation due to the impact of the virus on the respiratory system, which could affect the rhythm-generating and pattern-generating signals that are vital for regulating the respiratory rate and depth of breathing effort. The cerebral cortex, in conjunction with the brain stem centers, plays a crucial role in regulating ventilation during prolonged hypoxemia. This interaction between these two components may help elucidate the conscious respiratory sensation (or dyspnea) experienced by patients. It is hypothesized that neuroventilatory decoupling acts as a mechanism to prevent sensory signals from translating into mechanical or ventilatory responses. This decoupling phenomenon is believed to have a notable impact on the intensity of breathlessness. By understanding the relationship between increased ventilatory neural drive and abnormal gas exchange, particularly in the context of ventilation/perfusion (V/Q) mismatches and altered chemosensitivity, healthcare professionals can develop strategies to optimize respiratory support for COVID-19 patients. 展开更多
关键词 HYPOXEMIA Ventilatory Drive Dyspnea in COVID-19 Neuroventilatory Uncoupling
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解耦联蛋白2对大鼠肝纤维化形成中星形细胞活化的影响 被引量:2
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作者 安建多 江瑛 +1 位作者 白云飞 王学江 《解剖学报》 CAS CSCD 北大核心 2014年第4期480-484,共5页
目的探讨解耦联蛋白2(UCP2)在肝纤维化形成过程中的作用及其发生机制。方法体内实验采用四氯化碳(CCl4)诱导肝纤维化模型,取肝脏观察病理变化,用Western blotting、免疫组织化学和Real-time PCR等方法检测UCP2和p38丝裂素活化蛋白激酶(p... 目的探讨解耦联蛋白2(UCP2)在肝纤维化形成过程中的作用及其发生机制。方法体内实验采用四氯化碳(CCl4)诱导肝纤维化模型,取肝脏观察病理变化,用Western blotting、免疫组织化学和Real-time PCR等方法检测UCP2和p38丝裂素活化蛋白激酶(p38MAPK)的表达水平;体外实验采用UCP2特异性抑制剂京尼平和CCl4刺激星形细胞,检测UCP2和p38MAPK相关蛋白的表达情况。结果与正常组相比,模型组大鼠肝脏α-平滑肌肌动蛋白(α-SMA)和UCP2表达增高(P<0.05,n=10);加入CCl4刺激细胞后,星形细胞α-SMA表达增加,p38MAPK及其磷酸化水平增高(P<0.05,n=6);而在加入京尼平后,α-SMA表达增加,p38 MAPK及其磷酸化水平明显降低(P<0.05,n=6)。结论 UCP2参与了肝纤维化的发生,可能促进了星形细胞的活化及增殖过程。 展开更多
关键词 解耦联蛋白2 肝纤维化 星形细胞 P38丝裂素活化蛋白激酶 免疫印迹法 大鼠 UNCOUPLING protein 2
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Spectra of Off-diagonal Infinite-Dimensional Hamiltonian Operators and Their Applications to Plane Elasticity Problems 被引量:13
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作者 Alatancang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期200-204,共5页
In the present paper, the spectrums of off-diagonal infinite-dimensional Hamiltonian operators are studied. At first, we prove that the spectrum, the continuous-spectrum, and the union of the point-spectrum and residu... In the present paper, the spectrums of off-diagonal infinite-dimensional Hamiltonian operators are studied. At first, we prove that the spectrum, the continuous-spectrum, and the union of the point-spectrum and residual- spectrum of the operators are symmetric with respect to real axis and imaginary axis. Then for the purpose of reducing the dimension of the studied problems, the spectrums of the operators are expressed by the spectrums of the product of two self-adjoint operators in state spac,3. At last, the above-mentioned results are applied to plane elasticity problems, which shows the practicability of the results. 展开更多
关键词 plane elasticity problem SPECTRUM Hamiltonian operator uncoupled
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线粒体解偶联蛋白2在心力衰竭及运动心肌损伤中的研究进展 被引量:6
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作者 纪丽丽 李晓燕 《中国循证心血管医学杂志》 2015年第4期566-567,571,共3页
几乎所有类型的心脏、大血管疾病均可引起心力衰竭(心衰)。心衰时,机体会启动一系列代偿机制,如心脏前负荷增加、心肌肥厚、交感兴奋性增强、RAAS激活等。心肌肥厚以心肌纤维增多为主,能源供体的线粒体也相应增多。解偶联蛋白2(uncou... 几乎所有类型的心脏、大血管疾病均可引起心力衰竭(心衰)。心衰时,机体会启动一系列代偿机制,如心脏前负荷增加、心肌肥厚、交感兴奋性增强、RAAS激活等。心肌肥厚以心肌纤维增多为主,能源供体的线粒体也相应增多。解偶联蛋白2(uncoupling protein 2,UCP2)是位于线粒体内膜上的质子转运体,通过将内膜外的H+转运回线粒体基质,导致氧化磷酸化解偶联。在心衰的发生发展过程中, 展开更多
关键词 解偶联蛋白 线粒体内膜 UNCOUPLING 心脏前负荷 大血管疾病 代偿机制 肌损伤 活性氧 兴奋-收缩耦联 机体能量代谢
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Irisin对糖脂代谢的作用及机制研究 被引量:1
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作者 王明明 刘师伟 李欣 《中国药物与临床》 CAS 2016年第7期993-996,共4页
人体内白色脂肪组织主要作用是能量储存,以及分泌多种脂肪细胞因子及炎症因子参与胰岛素抵抗及相关疾病的发生。而棕色脂肪组织具有非战栗产热的能力,棕色脂肪含有丰富的线粒体,并可表达解耦联蛋白1(uncoupling protein1,UCP1),通过U... 人体内白色脂肪组织主要作用是能量储存,以及分泌多种脂肪细胞因子及炎症因子参与胰岛素抵抗及相关疾病的发生。而棕色脂肪组织具有非战栗产热的能力,棕色脂肪含有丰富的线粒体,并可表达解耦联蛋白1(uncoupling protein1,UCP1),通过UCP1使线粒体的氧化磷酸化解偶联,氧化分解脂肪,减少脂肪堆积。 展开更多
关键词 非战栗产热 棕色脂肪组织 脂肪细胞因子 白色脂肪 解耦联蛋白 糖脂代谢 胰岛素抵抗 Irisin 解偶联 UNCOUPLING
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Investigation of a mutual interaction force at different pressure amplitudes in sulfuric acid 被引量:3
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作者 Nastaran Rezaee Rasoul Sadighi-Bonabi +1 位作者 Mona Mirheydari Homa Ebrahimi 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期454-459,共6页
This paper investiages the secondary Bjerknes force for two oscillating bubbles in various pressure amplitudes in a concentration of 95% sulfuric acid. The equilibrium radii of the bubbles are assumed to be smaller th... This paper investiages the secondary Bjerknes force for two oscillating bubbles in various pressure amplitudes in a concentration of 95% sulfuric acid. The equilibrium radii of the bubbles are assumed to be smaller than 10 μm at a frequency of 37 kHz in various strong driving acoustical fields around 2.0 bars (1 bar=10^5 Pa). The secondary Bjerknes force is investigated in uncoupled and coupled states between the bubbles, with regard to the quasi-adiabatic model for the bubble interior. It finds that the value of the secondary Bjerknes force depends on the driven pressure of sulfuric acid and its amount would be increased by liquid pressure amplitude enhancement. The results show that the repulsion area of the interaction force would be increased by increasing the driven pressure because of nonlinear oscillation of bubbles. 展开更多
关键词 multi-bubble sonoluminescence secondary Bjerknes force coupled and uncoupled state nonlinear oscillation
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