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Hemodynamic changes in hepatic sinusoids of hepatic steatosis mice 被引量:6
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作者 Jing Fan Chong-Jiu Chen +3 位作者 Yu-Chen Wang Wei Quan Jian-Wei Wang Wei-Guang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2019年第11期1355-1365,共11页
BACKGROUND Fatty liver(FL) is now a worldwide disease. For decades, researchers have been kept trying to elucidate the mechanism of FL at the molecular level, but rarely involve the study of morphology and medical phy... BACKGROUND Fatty liver(FL) is now a worldwide disease. For decades, researchers have been kept trying to elucidate the mechanism of FL at the molecular level, but rarely involve the study of morphology and medical physics. Traditionally, it was believed that hemodynamic changes occur only when fibrosis occurs, but it has been proved that these changes already show in steatosis stage, which may help to reveal the pathogenesis and its progress. Because the pseudolobules are not formed during the steatosis stage, this phenomenon may be caused by the compression of the liver microcirculation and changes in the hemodynamics.AIM To understand the pathogenesis of hepatic steatosis and to study the hemodynamic changes associated with hepatic steatosis.METHODS Eight-week-old male C57 BL/6 mice were divided into three groups randomly(control group, 2-wk group, and 4-wk group), with 16 mice per group. A hepatic steatosis model was established by subcutaneous injection of carbon tetrachloride in mice. After establishing the model, liver tissue from mice was stained with hematoxylin and eosin(HE), and oil red O stains. Blood was collected from the angular vein, and hemorheological parameters were estimated. A two-photon fluorescence microscope was used to examine the flow properties of red blood cells in the hepatic sinusoids.RESULTS Oil red O staining indicated lipid accumulation in the liver after CCl_4 treatment.HE staining indicated narrowing of the hepatic sinusoidal vessels. No significant difference was observed between the 2-wk and 4-wk groups of mice onmorphological examination. Hemorheological tests included whole blood viscosity(mPas, γ = 10 s-1/γ = 100 s-1)(8.83 ± 2.22/4.69 ± 1.16, 7.73 ± 2.46/4.22 ±1.32, and 8.06 ± 2.88/4.22 ± 1.50), red blood cell volume(%)(51.00 ± 4.00, 42.00 ±5.00, and 40.00 ± 3.00), the content of plasma fibrinase(g/L)(3.80 ± 0.50, 2.90 ±0.80, and 2.30 ± 0.70), erythrocyte deformation index(%)(44.49 ± 5.81, 48.00 ±15.29, and 44.36 ± 15.01), erythrocyte electrophoresis rate(mm/s per V/m)(0.55 ±0.11, 0.50 ± 0.11, and 0.60 ± 0.20), revealing pathological changes in plasma components and red blood cells of hepatic steatosis. Assessment of blood flow velocity in the hepatic sinusoids with a laser Doppler flowmeter(mL/min per100 g)(94.43 ± 14.64, 80.00 ± 12.12, and 67.26 ± 5.92) and two-photon laser scanning microscope(μm/s)(325.68 ± 112.66, 213.53 ± 65.33, and 173.26 ± 44.02)revealed that as the modeling time increased, the blood flow velocity in the hepatic sinusoids decreased gradually, and the diameter of the hepatic sinusoids became smaller(μm)(10.28 ± 1.40, 6.84 ± 0.93, and 5.82 ± 0.79).CONCLUSION The inner diameter of the hepatic sinusoids decreases along with the decrease in the blood flow velocity within the sinusoids and the changes in the systemic hemorheology. 展开更多
关键词 HEPATIC STEATOSIS HEMODYNAMICS HEPATIC sinusoids TWO-PHOTON fluorescence microscopy Carbon TETRACHLORIDE
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Segmentation of Sinusoids in Hematoxylin and Eosin Stained Liver Specimens Using an Orientation-Selective Filter 被引量:1
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作者 Masahiro Ishikawa Sercan Taha Ahi +4 位作者 Fumikazu Kimura Masahiro Yamaguchi Hiroshi Nagahashi Akinori Hashiguchi Michiie Sakamoto 《Open Journal of Medical Imaging》 2013年第4期144-155,共12页
The liver comprises cell layers of hepatocytes called trabeculae, which are separated by vascular sinusoids. Under- standing the structure of hepatic trabeculae and liver sinusoids in hematoxylin and eosin (HE)-staine... The liver comprises cell layers of hepatocytes called trabeculae, which are separated by vascular sinusoids. Under- standing the structure of hepatic trabeculae and liver sinusoids in hematoxylin and eosin (HE)-stained liver specimens is important for the differential diagnosis of liver diseases. In this study, we develop an approach to extracting liver sinusoids from HE-stained images. The proposed approach involves: 1) a new orientation-selective filter (OS filter) for edge enhancement and image denoising, 2) the clustering of image pixels to identify candidate sinusoids, and 3) a classification procedure that discards unlikely candidates and selects the final sinusoid areas. Experimental studies using a database of 16 images with a resolution of 512 × 512 pixels showed that the proposed approach could segment liver sinusoid pixels with 81% of specificity and 94% of sensitivity. A comparison with a method based on bilateral filters showed that this method improved the sensitivity for all images with an average improvement of 4% and no difference in specificity. The results were presented to a group of pathologists and they confirmed that the images were highly representative of the tissue morphology features. 展开更多
关键词 HISTOPATHOLOGICAL Tissue Images Orientation-Selective Filter Segmentation of sinusoids
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Xilinx System Generator<sup>®</sup>Based Implementation of a Novel Method of Extraction of Nonstationary Sinusoids
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作者 Muhammad Abubakar Arshad Aziz Pervez Akhtar 《Journal of Signal and Information Processing》 2013年第3期7-13,共7页
Model based implementation of a novel nonlinear adaptive filter for extraction of time varying sinusoids using Xilinx system generator has been presented in this work. The practicality of this filter model along with ... Model based implementation of a novel nonlinear adaptive filter for extraction of time varying sinusoids using Xilinx system generator has been presented in this work. The practicality of this filter model along with its performance makes it one of the foremost candidates to be applied on nonlinear systems for the purpose of estimation and extraction using reconfigurable hardware like FPGA. A design implementation and verification approach has been discussed for more efficient implementation. Timing and power analysis has been performed and the architecture has been optimized for speed and power to perform at higher frequency when integrated on a Xilinx FPGA. The proposed hardware oriented architecture has been successfully implemented and simulated. The simulation results to track a noisy input have also been shown to demonstrate the exceptional performance of the hardware based architecture developed. 展开更多
关键词 XILINX System Generator FPGA Adaptive Filter Estimation SINUSOID Spatan6 Sta
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Effect of Semen Persicae Extract Combined with Cultured Cordyceps on Reversing Capillarization of Sinusoids In Patients with Hepato-Cirrhosis
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作者 徐列明 朱剑亮 +5 位作者 刘成 刘平 吕刚 薛惠明 明义杨 洪嘉禾 《Chinese Journal of Integrative Medicine》 SCIE CAS 1997年第3期203-205,共3页
Objective: To evaluate the effect of Semen Persicae combined with cultured Cordyceps on Reversing Capillarization of Sinusoids in patients with hepato-cirrhosis. Methods: Forty-four patients were treated for 3 months... Objective: To evaluate the effect of Semen Persicae combined with cultured Cordyceps on Reversing Capillarization of Sinusoids in patients with hepato-cirrhosis. Methods: Forty-four patients were treated for 3 months, the clinical and pathological effects were observed. Results: Patients were improved clinically.Pathological examination on liver biopsy of 6 patients also showed improvement in of capillarization of sinusoid,which mainly manifested by reduction of enlarged interhepatocellular spaces and collagen fiber in it, increase of lipid droplets within fat-storing cells (FSC), and decrease of proliferation of Kupffer cells. Conclusion: The combined treatment used could reverse the capillarization of sinusoid, and the mechanism might be related with its inhibition on activity and function of FSC. 展开更多
关键词 Semen Persicae Cordyceps sinensis AMYGDALIN hepato-cirrhosis capillarization of sinusoids
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Corrigendum to“Molecular dynamics study incorporating regression analysis:Quantitative effects of sinusoidal protrusions and wettability on water phase transition containing insoluble gases”
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《Chinese Physics B》 2026年第2期714-715,共2页
In Chin.Phys.B 34114704(2025),Eq.(7)and the associated unit notation were incorrect.The correct ones are present here.Since Eq.(7)is an in-built expression in the simulation package,the correction is purely typographi... In Chin.Phys.B 34114704(2025),Eq.(7)and the associated unit notation were incorrect.The correct ones are present here.Since Eq.(7)is an in-built expression in the simulation package,the correction is purely typographical and does not affect the simulation procedure,numerical results,or the conclusions. 展开更多
关键词 associated unit notation water phase transition WETTABILITY sinusoidal protrusions simulation packagethe insoluble gases simulation procedurenumerical molecular dynamics
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融合混沌映射和黄金正弦步长因子的多目标萤火虫算法
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作者 赵嘉 孔天伟 +2 位作者 肖人彬 王晖 樊棠怀 《兰州大学学报(自然科学版)》 北大核心 2025年第6期806-814,828,共10页
针对多目标萤火虫算法在进化过程中初始种群多样性差、求解精度低、易过早收敛等缺陷,提出一种融合混沌映射和黄金正弦步长因子的多目标萤火虫算法.用Sinusoidal映射的种群初始化技术,生成具有良好分布的初始种群;设计了一种黄金正弦步... 针对多目标萤火虫算法在进化过程中初始种群多样性差、求解精度低、易过早收敛等缺陷,提出一种融合混沌映射和黄金正弦步长因子的多目标萤火虫算法.用Sinusoidal映射的种群初始化技术,生成具有良好分布的初始种群;设计了一种黄金正弦步长因子的调整策略,利用正弦函数的所有值结合黄金分割系数动态调整步长因子,平衡算法的全局和局部搜索能力,有效提高算法的求解精度.引入Cauchy变异的个体扰动策略,使萤火虫个体在更新位置时产生较大的随机扰动以提高算法的全局搜索能力,降低算法陷入局部最优的概率.与5种经典优化算法和6种新近多目标优化算法在2-目标和3-目标测试函数上以反世代距离作为评价标准,对该算法进行性能测试,发现其在处理多目标问题时表现出良好的性能. 展开更多
关键词 多目标萤火虫算法 Sinusoidal映射 黄金正弦 步长因子 Cauchy变异
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Dual therapy with vildagliptin and sacubitril/valsartan alleviates portal hypertension and inhibits soluble epoxide hydrolase in cirrhotic rats
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作者 Masafumi Oyama Kosuke Kaji +10 位作者 Norihisa Nishimura Junichi Hanatani Tatsuya Nakatani Naoki Nishimura Akihiko Shibamoto Shohei Asada Yuki Tsuji Koh Kitagawa Shinya Sato Tadashi Namisaki Hitoshi Yoshiji 《World Journal of Gastroenterology》 2025年第33期113-130,共18页
BACKGROUND Portal hypertension(PH),a major complication of cirrhosis,arises from increased intrahepatic resistance and splanchnic vasodilation.Epoxyeicosatrienoic acids(EETs)improve hepatic microcirculation,but their ... BACKGROUND Portal hypertension(PH),a major complication of cirrhosis,arises from increased intrahepatic resistance and splanchnic vasodilation.Epoxyeicosatrienoic acids(EETs)improve hepatic microcirculation,but their effects are rapidly inactivated by soluble epoxide hydrolase(sEH),an enzyme upregulated in the cirrhotic liver.Inhibiting sEH increases EET levels,reducing portal pressure and fibrosis.Dipeptidyl peptidase-4 inhibitors(DPP4-Is)and angiotensin II blockers have been reported to suppress sEH and enhance EET activity.Angiotensin receptorneprilysin inhibitors(ARNIs)also lower portal pressure.However,the combined effect of DPP4-I and ARNI on the sEH-EET axis in PH and liver fibrosis remains uninvestigated.AIM To study the effects of vildagliptin,a DPP4-I and sacubitril/valsartan,an ARNI on PH and liver fibrosis in cirrhotic rats.METHODS Two rodent models of liver cirrhosis:(1)Choline-deficient,L-amino acid-defined,high-fat diet(CDAHFD)diet-fed rats;and(2)Bile duct ligation-induced rats were treated with vildagliptin(10 mg/kg/day),sacubitril/valsartan(30 mg/kg/day),or a combination of both drugs.Hemodynamic parameters,sEH activity,EET levels,vascular remodeling,and fibrosis were assessed using enzyme-linked immunosorbent assay,quantitative real-time polymerase chain reaction,Western blotting,histology,and immunofluorescence.RESULTS In CDAHFD-fed models,both DPP4-I and ARNI significantly reduced portal pressure in cirrhotic rats by decreasing intrahepatic vascular resistance without affecting systemic hemodynamics.These agents downregulated sEH expression and activity,increasing EET levels,and improved endothelial function via nitric oxide signaling enhancement.They also suppressed sinusoidal capillarization,pathological angiogenesis,and Hedgehog signaling,while restoring sinusoidal endothelial markers.Additionally,DPP4-I and ARNI attenuated liver fibrosis and stellate cell activation,reducing profibrotic gene expression.These effects were additive by the combination of both drugs.Similar effects were observed in bile duct ligation-induced PH,confirming their therapeutic potential in managing both PH and liver fibrosis through modulation of the sEH-EET pathway.CONCLUSION Combined DPP4-I with ARNI therapy ameliorates PH and fibrosis via sEH suppression and EET restoration,offering a promising treatment strategy for cirrhosis-related PH. 展开更多
关键词 Liver sinusoidal endothelial cell Liver fibrosis Capillarization ANGIOGENESIS Animal model
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Unmanned surface vehicles path planning with improved sparrow search algorithm
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作者 YU Hao WANG Xin PENG Hao 《Journal of Measurement Science and Instrumentation》 2025年第2期245-257,共13页
To enable optimal navigation for unmanned surface vehicle(USV),we proposed an adaptive hybrid strategy-based sparrow search algorithm(SSA)for efficient and reliable path planning.The proposed method began by enhancing... To enable optimal navigation for unmanned surface vehicle(USV),we proposed an adaptive hybrid strategy-based sparrow search algorithm(SSA)for efficient and reliable path planning.The proposed method began by enhancing the fitness function to comprehensively account for critical path planning metrics,including path length,turning angle,and navigation safety.To improve search diversity and effectively avoid premature convergence to local optima,chaotic mapping was employed during the population initialization stage,allowing the algorithm to explore a wider solution space from the outset.A reverse inertia weight mechanism was introduced to dynamically balance exploration and exploitation across different iterations.The adaptive adjustment of the inertia weight further improved convergence efficiency and enhanced global optimization performance.In addition,a Cauchy-Gaussian hybrid update strategy was incorporated to inject randomness and variation into the search process,which helped the algorithm escape local minima and maintain a high level of solution diversity.This approach significantly enhanced the robustness and adaptability of the optimization process.Simulation experiments confirmed that the improved SSA consistently outperformed benchmark algorithms such as the original SSA,PSO,and WMR-SSA.Compared with the three algorithms,in the simulated sea area,the path lengths of the proposed algorithm are reduced by 21%,21%,and 16%,respectively,and under the actual sea simulation conditions,the path lengths are reduced by 13%,15%,and 11%,respectively.The results highlighted the effectiveness and practicality of the proposed method,providing an effective solution for intelligent and autonomous USV navigation in complex ocean environments. 展开更多
关键词 fitness function steering angle chaotic mapping inverted inertia weights Cauchy distribution sinusoidal chaotic mapping
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Fatal air embolism during intestinal endoscopy in Kasai portoenterostomy for biliary atresia: A case report
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作者 So Young Shin Hee Jin Yeon +3 位作者 Sang On Lee Jeong Rim Lee Galam Leem Seok Joo Han 《World Journal of Gastrointestinal Endoscopy》 2025年第7期193-199,共7页
BACKGROUND Air embolism(AE)is a rare but potentially fatal complication of intestinal endoscopy(IE).CASE SUMMARY Herein,we report the case of an 18-year-old woman who underwent a successful Kasai portoenterostomy(KPE)... BACKGROUND Air embolism(AE)is a rare but potentially fatal complication of intestinal endoscopy(IE).CASE SUMMARY Herein,we report the case of an 18-year-old woman who underwent a successful Kasai portoenterostomy(KPE)for biliary atresia but died of AE during intraoperative IE for stone removal at the portoenterostomy site.Our review of the English literature identified only four similar cases of fatal AE during IE in patients undergoing KPE.The common clinical setting in the five patients,including our case,was high-pressure air insufflation into the blind closed afferent loop of the KPE to secure visibility.We hypothesize that the highly pressurized air injected into the closed loop entered the bile canaliculi—previously opened by KPE for bile drainage—passed through the tiny,microscopic pores of the fenestrated liver sinusoid endothelial cells,and finally entered the bloodstream with ease,resulting in fatal AE.CONCLUSION Meticulous performance of IE,especially on the KPE blind loop,is warranted owing to the risk of AE. 展开更多
关键词 Air embolism Intestinal endoscopy Biliary atresia Kasai portoenterostomy Fenestrated liver sinusoidal endothelial cell Case report
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Jitter suppression scheme for detection pulses in high-speed sinusoidal gated single-photon detectors
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作者 Lianjun Jiang Dongdong Li +11 位作者 Dawei Li Yuqiang Fang Ming Liu Wei Jiang Zhilin Xie Guoqing Liu Rui Ma Yukang Zhao Jian Sun Lei Chang Lin Yu Shibiao Tang 《Journal of Semiconductors》 2025年第12期72-77,共6页
Quantum key distribution(QKD)achieves information-theoretic security based on quantum mechanics principles,where single-photon detectors(SPDs)serve as critical components.This study focuses on the sinusoidal gated SPD... Quantum key distribution(QKD)achieves information-theoretic security based on quantum mechanics principles,where single-photon detectors(SPDs)serve as critical components.This study focuses on the sinusoidal gated SPDs widely used in high-speed QKD systems.We investigate the mechanisms underlying the rising-edge jitter in detection signals,identifying contributions from factors such as the temporal width of injected optical pulses,avalanche generation processes,avalanche signal extraction,and pulse discrimination.To address the issue of excessive jitter-induced bit errors,we propose a retiming scheme that utilizes coincidence signals synchronized with the sinusoidal gating signal.This approach effectively suppresses detection signal jitter and reduces the after-pulse probability of the detector.Experimental validation using a high-precision time-to-digital converter(TDC)demonstrates a significant reduction in the rising-edge jitter distribution after applying the suppression scheme.The proposed method features clear principles and straightforward engineering implementation,avoiding direct interference with the detector’s operational processes.The designed high-speed sinusoidal gated InGaAs/InP SPD operates at 1.25 GHz,achieving a remarkable reduction in after-pulse probability from 10.7%(without jitter suppression)to 0.72%,thereby enhancing the overall performance of QKD systems. 展开更多
关键词 single-photon detector high-speed sinusoidal gating avalanche signal extraction detection signal jitter suppression
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TSC22D1 promotes liver sinusoidal endothelial cell dysfunction and induces macrophage M1 polarization in non-alcoholic fatty liver disease
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作者 Wei Ding Xin-Qi Xu +9 位作者 Ling-Lin Wu Qun Wang Yi-Qin Wang Wei-Wei Chen Yu-Lin Tan Yi-Bo Wang Hua-Ji Jiang Jun Dong Yong-Min Yan Xue-Zhong Xu 《World Journal of Gastroenterology》 2025年第31期111-129,共19页
BACKGROUND The progression of non-alcoholic fatty liver disease(NAFLD)to non-alcoholic steatohepatitis(NASH)and liver fibrosis remains poorly understood,though liver sinusoidal endothelial cells(LSECs)are thought to p... BACKGROUND The progression of non-alcoholic fatty liver disease(NAFLD)to non-alcoholic steatohepatitis(NASH)and liver fibrosis remains poorly understood,though liver sinusoidal endothelial cells(LSECs)are thought to play a central role in disease pathogenesis.AIM To investigate the role of TSC22D1 in NAFLD fibrosis through its regulation of LSEC dysfunction and macrophage polarization.METHODS We analysed single-cell transcriptomic data(GSE129516)from NASH and normal INTRODUCTION Non-alcoholic fatty liver disease(NAFLD)is a global health issue associated with increasing rates of obesity and metabolic syndrome.NAFLD encompasses a spectrum of conditions,ranging from simple steatosis to more severe manifestations such as non-alcoholic steatohepatitis(NASH),fibrosis,cirrhosis,and hepatocellular carcinoma.Liver fibrosis represents a critical stage in NAFLD progression because of its strong association with impaired liver function,progression to end-stage liver disease,and increased disease-related mortality[1].The pathogenesis of NAFLD is multifactorial and involves complex interactions between genetic predispositions,insulin resistance,dietary factors,and chronic inflammation[2].Liver sinusoidal endothelial cells(LSECs),which are highly specialized endothelial cells lining the hepatic sinusoids,critically contribute to both the pathogenesis and progression of NAFLD[3,4].In NAFLD,LSECs undergo structural alterations such as reduced fenestrations,which impair hepatic microcirculation and hinder the exchange of lipids and other substances,thereby promoting lipid accumulation in hepatocytes[5].Furthermore,dysfunctional LSECs exacerbate hepatic inflammation and fibrogenesis by releasing pro-inflammatory cytokines and fibrogenic mediators,such as transforming growth factor-β(TGF-β).These factors activate hepatic stellate cells(HSCs),resulting in the pathological accumulation of extracellular matrix components[6].LSECs are also highly susceptible to oxidative stress,further aggravating hepatic injury[7,8].Importantly,LSECs influence macrophage polarization by producing chemotactic and immunomodulatory factors,thereby promoting the recruitment and activation of M1-type pro-inflammatory CONCLUSION In conclusion,this study provides a comprehensive understanding of the role of TSC22D1 in the pathogenesis of NAFLD fibrosis.We elucidated the mechanisms through which TSC22D1 drives LSEC microvascularization and EndMT,as well as its role in promoting the secretion of TWEAK,which induces macrophage polarization towards the M1 phenotype.These findings offer novel insights into the pathophysiology of NAFLD,particularly the interplay between endothelial dysfunction,inflammation,and fibrosis.Importantly,our results highlight the potential of TSC22D1 as a therapeutic target for NAFLD.Future research should focus on validating these mechanisms in human clinical cohorts and deve-loping targeted interventions,such as TSC22D1 inhibitors or modulators of the TWEAK/FN14 signalling pathway,to translate these findings into effective treatments for NAFLD progression to fibrosis. 展开更多
关键词 Liver sinusoidal endothelial cells TSC22D1 Non-alcoholic fatty liver disease Macrophage polarization Tumor necrosis factor-like weak inducer of apoptosis
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变尺度混沌光强吸收系数的萤火虫优化算法 被引量:7
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作者 徐华丽 苏守宝 +1 位作者 陈家俊 牛应轩 《计算机应用研究》 CSCD 北大核心 2015年第2期368-371,共4页
针对基本萤火虫算法存在早熟现象,提出了一种变尺度混沌光强吸收系数调整策略的混沌萤火虫优化算法。首先,应用Sinusoidal映射产生混沌变量来描述光强吸收系数;其次,在算法迭代过程中引入变尺度混沌扰动,使光强吸收系数与迭代次数呈线... 针对基本萤火虫算法存在早熟现象,提出了一种变尺度混沌光强吸收系数调整策略的混沌萤火虫优化算法。首先,应用Sinusoidal映射产生混沌变量来描述光强吸收系数;其次,在算法迭代过程中引入变尺度混沌扰动,使光强吸收系数与迭代次数呈线性变化;最后,将萤火虫群分成三个子种群协作合作,可有利于增强算法搜索前期的全局探索能力和搜索后期的局部细化搜索能力。通过标准测试函数测试,实验结果表明算法是有效的,比基本萤火虫算法有了较好的寻优精度和收敛速度。 展开更多
关键词 群智能 萤火虫算法 混沌 Sinusoidal映射 变尺度混沌算子
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Natural history of hepatic metastases from colorectal cancer-pathobiological pathways with clinical significance 被引量:10
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作者 Konstantinos A Paschos Ali W Majeed Nigel C Bird 《World Journal of Gastroenterology》 SCIE CAS 2014年第14期3719-3737,共19页
Colorectal cancer hepatic metastases represent the final stage of a multi-step biological process.This process starts with a series of mutations in colonic epithelial cells,continues with their detachment from the lar... Colorectal cancer hepatic metastases represent the final stage of a multi-step biological process.This process starts with a series of mutations in colonic epithelial cells,continues with their detachment from the large intestine,dissemination through the blood and/or lymphatic circulation,attachment to the hepatic sinusoids and interactions with the sinusoidal cells,such as sinusoidal endothelial cells,Kupffer cells,stellate cells and pit cells.The metastatic sequence terminates with colorectal cancer cell invasion,adaptation and colonisation of the hepatic parenchyma.All these events,termed the colorectal cancer invasion-metastasis cascade,include multiple molecular pathways,intercellular interactions and expression of a plethora of chemokines and growth factors,and adhesion molecules,such as the selectins,the integrins or the cadherins,as well as enzymes including matrix metalloproteinases.This review aims to present recent advances that provide insights into these cell-biological events and emphasizes those that may be amenable to therapeutic targeting. 展开更多
关键词 Colorectal cancer Metastatic cascade Liver metastasis Liver sinusoids NEOVASCULARIZATION
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Simulation of pavement roughness based on time domain model 被引量:2
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作者 钮凯健 李昶 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期475-479,共5页
In order to describe pavement roughness more intuitively and effectively, a method of pavement roughness simulation, i.e., the stochastic sinusoidal wave, is introduced. The method is based on the primary idea that pa... In order to describe pavement roughness more intuitively and effectively, a method of pavement roughness simulation, i.e., the stochastic sinusoidal wave, is introduced. The method is based on the primary idea that pavement roughness is denoted as the sum of numerous sines or cosines with stochastic phases, and uses the discrete spectrum to approach the target stochastic process. It is a discrete numerical method used to simulate pavement roughness. According to a given pavement power spectral density (PSD) coefficient, under the condition that the character of displacement frequency based on the time domain model is in accordance with the given pavement surface spectrum, the pavement roughness is optimized to stochastic equivalent vibrations by computer simulation, and the curves that describe pavement roughness under each grade are obtained. The results show that the stochastic sinusoidal wave is suitable for simulation of measured pavement surface spectra based on the time domain model. The method of the stochastic sinusoidal wave is important to the research on vehicle ride comfort due to its rigorous mathematical derivation, extensive application range and intuitive simulation curve. Finally, a roughness index defined as the nominal roughness index (NRI) is introduced, and it has correlation with the PSD coefficient. 展开更多
关键词 pavement roughness stochastic sinusoidal wave stochastic process power spectral density (PSD) coefficient time domain nominal roughness index (NRI)
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基于鸟群搜索行为和余弦变异的改进白鲨优化算法 被引量:2
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作者 张超 杨忆 《西华大学学报(自然科学版)》 CAS 2023年第3期94-104,共11页
白鲨优化算法是受白鲨捕猎行为的启发设计的一种新元启发式算法。该算法在求解高维优化问题时,易进入早熟状态,寻优结果精度较低。为此,文章提出一种改进的白鲨优化(improved white shake optimizer,IWSO)算法。首先使用Sinusoidal混沌... 白鲨优化算法是受白鲨捕猎行为的启发设计的一种新元启发式算法。该算法在求解高维优化问题时,易进入早熟状态,寻优结果精度较低。为此,文章提出一种改进的白鲨优化(improved white shake optimizer,IWSO)算法。首先使用Sinusoidal混沌映射初始化种群,以提高种群多样性及初始解在解空间的分布性;其次,引入鸟群搜索行为,赋予白鲨游动速度自适应动态惯性权重,以提高算法的收敛速度;最后,在位置更新阶段引入精英白鲨余弦变异策略,利用余弦函数的周期性特征,驱使白鲨个体在精英白鲨的有限邻域内进行精细化开发,以提高收敛精度。在23个著名基准函数和CEC2014函数上做了性能对比实验,其结果表明,IWSO算法优于6种对比算法,适合求解函数优化问题。 展开更多
关键词 白鲨优化算法 余弦精英变异 Sinusoidal混沌映射 鸟群搜索行为 元启发式算法
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Application of Atomic Sparse Decomposition to Feature Extraction of the Fault Signal in Small Current Grounding System 被引量:1
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作者 Nanhua Yu Rui Li +1 位作者 Jun Yang Bei Dong 《Energy and Power Engineering》 2013年第4期603-607,共5页
Applying the atomic sparse decomposition in the distribution network with harmonics and small current grounding to decompose the transient zero sequence current that appears after the single phase to ground fault occu... Applying the atomic sparse decomposition in the distribution network with harmonics and small current grounding to decompose the transient zero sequence current that appears after the single phase to ground fault occurred. Based on dictionary of Gabor atoms and matching pursuit algorithm, the method extracts the atomic components iteratively from the feature signals and translated them to damped sinusoidal components. Then we can obtain the parametrical and analytical representation of atomic components. The termination condition of decomposing iteration is determined by the threshold of the initial residual energy with the purpose of extract the features more effectively. Accordingly, the proposed method can extract the starting and ending moment of disturbances precisely as well as their magnitudes, frequencies and other features. The numerical examples demonstrate its effectiveness. 展开更多
关键词 Small Current GROUNDING System Fault Line Selection ATOMIC SPARSE Decomposition Matching PURSUIT DAMPED sinusoids
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协作设计众包任务优化分配建模与求解 被引量:1
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作者 刘电霆 吴丹玲 黄康政 《机械设计》 CSCD 北大核心 2021年第6期124-132,共9页
为解决产品设计中协作设计众包任务优化分配问题,建立了一个子任务对设计者匹配满意和设计者对子任务匹配满意的多目标优化模型,并提出一种改进的麻雀搜索算法进行求解。该模型以协作设计众包子任务和设计者双方最大匹配满意度为目标,... 为解决产品设计中协作设计众包任务优化分配问题,建立了一个子任务对设计者匹配满意和设计者对子任务匹配满意的多目标优化模型,并提出一种改进的麻雀搜索算法进行求解。该模型以协作设计众包子任务和设计者双方最大匹配满意度为目标,从而建立双方的一对一匹配。对算法进行改进,利用Sinusoidal混沌映射初始化种群;利用正余弦算法指引所有麻雀个体向最优位置移动。为防止最优解陷入局部最优,对最优解加带惯性的柯西变异扰动;将改进的算法在6个基准测试函数上进行性能验证。试验结果表明:改进后的麻雀搜索算法寻优能力优于灰狼优化算法(GWO)、蝙蝠算法(BA)及麻雀搜索算法(SSA),并举出实例说明了方法的可行性。 展开更多
关键词 产品设计 任务优化分配模型 麻雀搜索算法 Sinusoidal映射 柯西变异
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逆变器供电双三相异步电机系统的MATALB仿真
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作者 谢芳芳 郑剑 《电气自动化》 2014年第2期18-22,共5页
为了深入研究多相变频调速系统,需要建立逆变器供电双三相异步电机系统的仿真模型。在双三相异步电机的动态数学模型基础上,利用MATLAB中的Simulink模块库和SimPowerSystems模块库构造逆变器与电机系统的仿真模型,属于信号流与电气流混... 为了深入研究多相变频调速系统,需要建立逆变器供电双三相异步电机系统的仿真模型。在双三相异步电机的动态数学模型基础上,利用MATLAB中的Simulink模块库和SimPowerSystems模块库构造逆变器与电机系统的仿真模型,属于信号流与电气流混合仿真,能够较好反映逆变器的电气特性。对模型分别施加正弦电压激励、SPWM电压激励,进行空载起动和突加负载等实验,仿真结果表明了模型的正确性和有效性。 展开更多
关键词 多相变频调速 逆变器 双三相异步电机 正弦脉宽调制 动态仿真 sinusoidal PULSE WIDTH modulation (SPWM)
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THE RELATIONSHIP BETWEEN HEPATIC PATHOLOGIC CHANGES AND PORTAL VENOUS PRESSURE DURING DEVELOPMENT OF CIRRHOSIS IN RATS
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作者 吴志勇 黄安 +4 位作者 郑忠华 陈治平 邝耀麟 小野慶一 金充 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1991年第1期14-22,共9页
In order to pinpoint the site causing increased intrahepatic vascular resistance, we observed the relationship between hepatic pathologic changes and free portal pressurre (FPP) during the development of CCl<sub&... In order to pinpoint the site causing increased intrahepatic vascular resistance, we observed the relationship between hepatic pathologic changes and free portal pressurre (FPP) during the development of CCl<sub>4</sub>-induced liver cirrhosis of rat. The results suggested that the degeneration necrosis and regeneration of liver cells, and consequent stenosis, or obliteration of sinusoidal spaces caused by the swelling and disarrangement of the liver cell plates led to the occurence of portal hypertension, The possibility of pre-or post-sinusoidal obstruction was excluded by the manifestation of the pathologic lesions. It is the authors’ belief that the exact site of the increased intrahepatic vascular resistance was most likely at the level of hepatic sinusoids. Furthermore, there was certain positive correlation between plasma glucagon concentration and FPP, indicating that glucagon was also involved in the pathogenesis of portal hypertension. 展开更多
关键词 INTRAHEPATIC vascular resistance CIRRHOSIS of liver portal hypertension stenosis of HEPATIC sinusoids plasma GLUCAGON
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增强型野马优化算法及其工程应用 被引量:2
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作者 马志海 刘升 《计算机应用研究》 CSCD 北大核心 2024年第7期2061-2068,共8页
针对野马优化算法易陷入局部最优、收敛速度慢等缺点,提出增强型野马优化算法。首先,在种群初始化阶段,采用Sinusoidal映射,增加种群的多样性;其次,在阶段更新过程中,设计出非线性收敛性更强的自适应权重,调节全局搜索和局部优化能力;然... 针对野马优化算法易陷入局部最优、收敛速度慢等缺点,提出增强型野马优化算法。首先,在种群初始化阶段,采用Sinusoidal映射,增加种群的多样性;其次,在阶段更新过程中,设计出非线性收敛性更强的自适应权重,调节全局搜索和局部优化能力;然后,在更新领导者位置阶段加入扰动因子,平衡局部和全局探索能力;进一步,利用自适应t分布变异,对个体位置进行扰动,提高算法跳出局部最优的能力。通过在CEC2021测试竞赛进行测试优化比较,验证算法的有效性和稳健性,并利用Wilcoxon秩和检验和MAE排名,验证算法的有效性。最后将算法应用到工程难题问题中,验证了其在工程优化问题上的适用性与优越性。实验结果表明,与其他智能算法相比,增强型野马优化算法具有更强的寻优能力和更快的收敛速度。 展开更多
关键词 野马优化算法 Sinusoidal映射 自适应t分布 工程优化
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