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Multi-Material Topology Optimization for Spatial-Varying Porous Structures 被引量:1
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作者 Chengwan zhang Kai Long +4 位作者 Zhuo Chen Xiaoyu Yang Feiyu Lu jinhua zhang Zunyi Duan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期369-390,共22页
This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volu... This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures. 展开更多
关键词 Topology optimization porous structures local volume fraction augmented lagrangian multiple materials
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An Overview of Sequential Approximation in Topology Optimization of Continuum Structure
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作者 Kai Long Ayesha Saeed +6 位作者 jinhua zhang Yara Diaeldin Feiyu Lu Tao Tao Yuhua Li Pengwen Sun Jinshun Yan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期43-67,共25页
This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encounter... This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encountered in engineering applications,often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design variables.As a result,sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization challenges.Over the past several decades,topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical backgrounds.In comparison to the large-scale equation solution,sensitivity analysis,graphics post-processing,etc.,the progress of the sequential approximation functions and their corresponding optimizersmake sluggish progress.Researchers,particularly novices,pay special attention to their difficulties with a particular problem.Thus,this paper provides an overview of sequential approximation functions,related literature on topology optimization methods,and their applications.Starting from optimality criteria and sequential linear programming,the other sequential approximate optimizations are introduced by employing Taylor expansion and intervening variables.In addition,recent advancements have led to the emergence of approaches such as Augmented Lagrange,sequential approximate integer,and non-gradient approximation are also introduced.By highlighting real-world applications and case studies,the paper not only demonstrates the practical relevance of these methods but also underscores the need for continued exploration in this area.Furthermore,to provide a comprehensive overview,this paper offers several novel developments that aim to illuminate potential directions for future research. 展开更多
关键词 Topology optimization sequential approximate optimization convex linearization method ofmoving asymptotes sequential quadratic programming
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Puerarin alleviates sleep disorders in aged mice related to repairing intestinal mucosal barrier
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作者 Qing Tao jinhua zhang +5 位作者 Qiao liang Shiyu Song Shuxia Wang Xiaoming Yao Qian Gao Lei Wang 《Natural Products and Bioprospecting》 CSCD 2023年第1期464-476,共13页
More and more evidence suggests that puerarin,a potential remedy for gut inflammation,may have an ameliorative effect on sleep disturbances.However,the relationship between puerarin and sleep disruption has not been e... More and more evidence suggests that puerarin,a potential remedy for gut inflammation,may have an ameliorative effect on sleep disturbances.However,the relationship between puerarin and sleep disruption has not been extensively researched.This study aims to explore the role and mechanisms of puerarin in improving sleep disorders.We established a light-induced sleep disorder model in mice and assessed the effects of puerarin on cognitive behavior using open field and water maze tests.Pathological detection demonstrated that sleep disturbances resulted in observable damage to the liver,lung,and kidney.Puerarin reversed multi-organ damage and inflammation.Further,puerarin activated paneth cells,resulting in increased lysozyme and TGF-βproduction,and stimulating intestinal stem cell proliferation.Puerarin also effectively inhibited the expression of F4/80,iNOS,TNF-α,and IL-1βin the small intestine,while it increased Chil3,CD206,and Arg-1 levels.Moreover,puerarin treatment significantly decreased P-P65,TLR4,Bcl-xl,and cleaved caspase-3 protein levels while increasing barrier protein levels,including ZO-1,Occludin,Claudin 1 and E-cadherin suggesting a reduction in inflammation and apoptosis in the gut.Overall,puerarin diminished systemic inflammation,particularly intestinal inflammation,and enhanced intestinal barrier integrity in mice with sleep disorders.Our findings suggest a potential new therapeutic pathway for sleep disorders. 展开更多
关键词 Intestinal inflammation Intestinal mucosal barrier Light-induced sleep disorder PUERARIN
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Visual Feedback Disturbance Rejection Control for an Amphibious Bionic Stingray Under Actuator Saturation
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作者 Haiyan Cheng Bin Fang +2 位作者 Qing Liu jinhua zhang Jun Hong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期566-568,共3页
Dear Editor,This letter is concerned with visual feedback disturbance rejection control for an amphibious bionic stingray subject to actuator saturation with internal and external disturbances. A visual feedback contr... Dear Editor,This letter is concerned with visual feedback disturbance rejection control for an amphibious bionic stingray subject to actuator saturation with internal and external disturbances. A visual feedback control method is designed for a dynamic nonlinear system on yaw angle of the amphibious bionic stingray via a finite-time extended-stateobserver,which is proved to achieve finite-time stability via a Lyapunov method. Finally, simulation results verify the effectiveness on the visual feedback control method. 展开更多
关键词 VISUAL concerned SATURATION
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Curcumin protects against ischemic spinal cord injury The pathway effect 被引量:9
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作者 jinhua zhang Hao Wei +3 位作者 Meimei Lin Chunmei Chen Chunhua Wang Maobai Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第36期3391-3400,共10页
Inducible nitric oxide synthase and N-methyI-D-aspartate receptors have been shown to participate in nerve cell injury during spinal cord ischemia. This study observed a protective effect of curcumin on ischemic spina... Inducible nitric oxide synthase and N-methyI-D-aspartate receptors have been shown to participate in nerve cell injury during spinal cord ischemia. This study observed a protective effect of curcumin on ischemic spinal cord injury. Models of spinal cord ischemia were established by ligating the lumbar artery from the left renal artery to the bifurcation of the abdominal aorta. At 24 hours after model establishment, the rats were intraperitoneally injected with curcumin, Reverse transcrip- tion-polymerase chain reaction and immunohistochemical results demonstrated that after spinal cord ischemia, inducible nitric oxide synthase and N-methyI-D-aspartate receptor mRNA and protein expression significantly increased. However, curcumin significantly decreased inducible nitric oxide synthase and N-methyI-D-aspartate receptor mRNA and protein expression in the ischemic spinal cord. Tadov scale results showed that curcumin significantly improved motor function of the rat hind limb after spinal cord ischemia. The results demonstrate that curcumin exerts a neuroprotective ef- fect against ischemic spinal cord injury by decreasing inducible nitric oxide synthase and N-methyI-D-aspartate receptor expression. 展开更多
关键词 neural regeneration traditional Chinese medicine CURCUMIN spinal cord injury ischemic injury N-methyI-D-aspartate receptor inducible nitric oxide synthase NEUROPROTECTION grants-supported paper NEUROREGENERATION
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Interception, degradation and contributions of terrestrial organic carbon obtained from lignin analysis in Wujiang River, southwest China 被引量:3
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作者 Xin Lin Yujie Wang +4 位作者 jinhua zhang Ming Yang Xueping Chen Fushun Wang Jing Ma 《Acta Geochimica》 EI CAS CSCD 2021年第6期857-870,共14页
Understanding the fate of terrestrial organic carbon(OC)in a cascade impoundment system is critical for recognizing the role of carbon sink for reservoirs.Surface sediments collected from eight cascade reservoirs acro... Understanding the fate of terrestrial organic carbon(OC)in a cascade impoundment system is critical for recognizing the role of carbon sink for reservoirs.Surface sediments collected from eight cascade reservoirs across the Wujiang River,southwestern China,were analyzed for elemental and stable carbon isotopic(δ^13C)composition,and lignin phenols(∑8 andΛ8)to investigate the spatial distribution,contribution,origin and degradation of sedimentary terrestrial OC.The values of total organic carbon(TOC)and∑8 exhibited a remarkable reduction along the upstream-downstream transect suggesting the trapping effect of cascade-damming.A relatively broad range ofδ^13C(-26.61 to-25.54%,95%CI)and C/N(6.80-18.20)indicated mixed allochthonous/autochthonous OC sources in surface sediments.The quantitative simulation indicates that the OC of the sediments mainly was derived from terrestrial organic matter.Soilderived OC rather than C_(3)vascular plant-derived OC makes a major contribution to sedimentary terrestrial OC in reservoirs on karst terrain.As evidenced by lignin compositions andδ^13C,the predominant vascular plant origins of terrestrial OC along the Wujiang River are non-woody angiosperm C_(3)plants.The aged reservoirs showed a trend of increasing contribution of autochthonous OC,which potentially weaken the role of carbon sink for reservoirs.The relationship between runoff inputs,watershed area/water surface area ratios,and water residence time and Λ8 were explored,indicating the natural and anthropogenic influences on terrestrial OC remains very complex in a cascade-damming river. 展开更多
关键词 Lignin phenols Terrestrial organic carbon Cascade impoundment
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Three-Dimensional Mesoscopic Investigation on the Impact of Specimen Geometry and Bearing Strip Size on the Splitting-Tensile Properties of Coral Aggregate Concrete 被引量:2
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作者 zhangyu Wu jinhua zhang +3 位作者 Hongfa Yu Qin Fang Haiyan Ma Li Chen 《Engineering》 SCIE EI CAS 2022年第10期110-122,共13页
The use of coral aggregate concrete(CAC)as a novel construction material has attracted significant attention for the construction of reef engineering structures.To investigate the static splitting-tensile behaviors of... The use of coral aggregate concrete(CAC)as a novel construction material has attracted significant attention for the construction of reef engineering structures.To investigate the static splitting-tensile behaviors of CAC under the influence of two factors,namely specimen geometry and bearing strip size,a three-dimensional(3D)mesoscale modeling approach with consideration for aggregate randomness in shape and distribution was adopted in this study.We established 12 different specimen models with two specimen shapes(i.e.,a cube with an edge length of 150 mm and a cylinder with dimensions ofφ150 mm×300 mm)and six strip widths(i.e.,6,9,12,15,18,and 20 mm)for calculation.The effects of specimen geometry and strip width on the splitting-tensile properties of CAC,such as failure processes,final failure patterns,and splitting-tensile strength(fst),are analyzed and discussed systematically.The results indicate the high reliability of the developed mesoscale modeling approach and reveal the optimal computational parameters for simulating and predicting the splitting-tensile properties of CAC.The fstvalues of CAC are associated with both the specimen geometry and width of the bearing strip.The fstvalues of the cube model are slightly higher than those of the cylinder model for the same bearing strip size,representing geometry effects that can be explained by differences in fracture area.Additionally,the fstvalue of CAC gradually increases with the relative width of the bearing strip ranging from 0.04 to 0.13.Based on the elastic solution theory,the variation area of CAC fstvalues with the relative width of the bearing strip was determined preliminarily,which has great significance for studying the tensile performance of CAC. 展开更多
关键词 Coral aggregate concrete 3D mesoscopic modelling Splitting-tensile test Tensile strength Specimen geometry Bearing strip
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Mesoscopic Modeling Approach and Application for Steel Fiber Reinforced Concrete under Dynamic Loading:A Review 被引量:2
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作者 jinhua zhang zhangyu Wu +2 位作者 Hongfa Yu Haiyan Ma Bo Da 《Engineering》 SCIE EI CAS 2022年第9期220-238,共19页
Steel fiber reinforced concrete(SFRC)has drawn extensive attention in recent years for its superior mechanical response to dynamic and impact loadings.Based on the existing test results,the highstrength steel fibers e... Steel fiber reinforced concrete(SFRC)has drawn extensive attention in recent years for its superior mechanical response to dynamic and impact loadings.Based on the existing test results,the highstrength steel fibers embedded in a concrete matrix usually play a strong bridging effect to enhance the bonding force between fiber and the matrix,and directly contribute to the improvement of the post-cracking behavior and residual strength of SFRC.To gain a better understanding of the action behavior of steel fibers in matrix and further capture the failure mechanism of SFRC under dynamic loads,the mesoscopic modeling approach that assumes SFRC to be composed of different mesoscale phases(i.e.,steel fibers,coarse aggregates,mortar matrix,and interfacial transition zone(ITZ))has been widely employed to simulate the dynamic responses of SFRC material and structural members.This paper presents a comprehensive review of the state-of-the-art mesoscopic models and simulations for SFRC under dynamic loading.Generation approaches for the SFRC mesoscale model in the simulation works,including steel fiber,coarse aggregate,and the ITZ between them,are reviewed and compared systematically.The material models for different phases and the interaction relationship between fiber and concrete matrix are summarized comprehensively.Additionally,some example applications for SFRC under dynamic loads(i.e.,compression,tension,and contact blast)simulated using the general mesoscale models are given.Finally,some critical analysis on the current shortcomings of the mesoscale modeling of SFRC is highlighted,which is of great significance for the future investigation and development of SFRC. 展开更多
关键词 Steel fiber reinforced concrete Mesoscale modeling Dynamic loading Materials model Interfacial characteristic
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Influence of compound aescine gel on ultrastructure of vein infused mannitol and its mechanism 被引量:4
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作者 jinhua zhang Hefang Wang +2 位作者 Yanling Gui Wei Li Wei Zhou 《Forensic Medicine and Anatomy Research》 2013年第2期30-35,共6页
Purpose: When hypertonic solution 20% mannitol solution was injected into vein, inflammatory mediators and Mitogen-activated protein kinases activated by mannitol can directly induce the fading of vascular endothelial... Purpose: When hypertonic solution 20% mannitol solution was injected into vein, inflammatory mediators and Mitogen-activated protein kinases activated by mannitol can directly induce the fading of vascular endothelial cell, which leads to phlebitis. The study aims to observe the influences of reparil-gel N coated at the proximal parts of the puncture point and basing on this along with infusing heated mannitol to veins to the injure and ultrastructure of veins which were infused the 20% mannitol solution by indwelling needle in vein. Methodology: There are 15 adult New Zealand rabbits. We randomly divided 24 ear veins of 12 adult New Zealand rabbits into Control group, Gelatum group, Gel heated group and injected 20% mannitol solution by vein detained needle in three groups. In Gelatum group, we coated the proximal end of the puncture point with a thin layer of compound aescine gel. Based on Gelatum group, we heated 20% mannitol solution to 35oC-37oC in Gel heated group. Then we observed the intravenous parts and took the veins of each group out to observe their morphology and ultrastructural after the second day of transfusion. 6 ear veins of the rest 3 rabbits as Health group weren’t given any interventions, the veins were taken out to observe their morphology. Results: Comparison between Gelatum group and Gelatum heated group on vascular dilatation, Infiltration of inflammatory cell and Formation of thrombus had no significance, P> 0.05, while the case was different for the comparison on injury of vascular wall, perivascular edema and perivascular hemorrhage, P< 0.05). The statistical significance exists between control group and Gelatum group and Gel heated group, P< 0.05. It was observed under the electron microscope that, in control group, the membrane of endothelial cell peeled off and the mitochondria swelled and vacuolized. In Gelatum group, the membrane of endothelial cell was defective, the parts of the mitochondria were fuzzy, intercellular substance was slightly edematous. In Gel heated group, the mitochondria were clear and intercellular substance slightly swelled. It could be found that the function of phagocyte was complete. Conclusions: Compound aescine gel can prevent phlebitis or reduce the incidence of phlebitis. The combined intervention of coating with a thin layer of compound aescine gel and heating mannitol solution can produce better effect. 展开更多
关键词 Hyperosmotic Solution COMPOUND Aescine GEL PHLEBITIS VEIN Detained Needle ULTRASTRUCTURE
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Unveiling the decomposition mechanism of formic acid on Pd/WC(0001) surface by using density function theory 被引量:1
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作者 jinhua zhang Yuanbin She 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期415-425,共11页
In pursuit of low-cost direct formic acid fuel cells,tungsten carbide(WC)supported Pd catalyst is considered as an ideal candidate for efficient decomposition of formic acid due to low Pd utilization and excellent per... In pursuit of low-cost direct formic acid fuel cells,tungsten carbide(WC)supported Pd catalyst is considered as an ideal candidate for efficient decomposition of formic acid due to low Pd utilization and excellent performance.Herein,different adsorption configurations and active sites of the intermediates,involved in the HCOOH decomposition,on WC(0001)-supported Pd monolayer(Pd/WC(0001))surface investigated by using density functional theory.The results reveal that trans-HCOOH,HCOO,cis-COOH,trans-COOH,HCO,CO,H2 O,OH and H exhibit chemisorption on Pd/WC(0001)surface,whereas cis-HCOOH and CO2 exhibit weak interactions with Pd/WC(0001)surface.In addition,the minimum energy pathways of HCOOH decomposition are analyzed to generate CO and CO2 due to the fracture of C–H,H–O and C–O bonds.The adsorbed HCOOH,HCOO,mH COO,cis-COOH and trans-COOH configurations exhibit dissociation rather than desorption.CO formation occurs through the decomposition of cis-COOH,trans-COOH and HCO,whereas the CO2 formation happens due to the decomposition of HCOO.It is found that the most favorable pathway for HCOOH decomposition on Pd/WC(0001)surface is HCOOH→HCOO→CO2,where the formation of CO2 from HCOO dehydrogenation determines the reaction rate.Overall,CO2 is the most dominant product of HCOOH decomposition on Pd/WC(0001)surface.The presence of WC,as monolayer Pd carrier,does not alter the catalytic behavior of Pd and significantly reduces the Pd utilization. 展开更多
关键词 Density functional theory Formic acid Direct formic acid fuel cells WC(0001)-supported Pd monolayer Decomposition mechanism
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Preliminary clinical application of an adaptive iterative statistical reconstruction algorithm inhead and neck computed tomography angiography with low tube voltage and a low concentration of contrast medium 被引量:1
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作者 Shan Hu Wenzhen Zhu +4 位作者 Daoyu Hu XiaoYan Meng jinhua zhang Weijia Wan Li Zhou 《Oncology and Translational Medicine》 CAS 2015年第4期171-176,共6页
Objective To evaluate the feasibility of using a low concentration of contrast medium (Visipaque 270 mgl/mL), low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography ang... Objective To evaluate the feasibility of using a low concentration of contrast medium (Visipaque 270 mgl/mL), low tube voltage, and an advanced image reconstruction algorithm in head and neck computed tomography angiography (CTA). Methods Forty patients (22 men and 18 women; average age 48.7 ± 14.25 years; average body mass index 23.9 ± 3.7 kg/m^2) undergoing CTA for suspected vascular diseases were randomly assigned into two groups. Group A (n = 20) was administered 370 mgl/mL contrast medium, and group B (n = 20) was administered 270 mgl/mL contrast medium. Both groups were administered at a rate of 4.8 mL/s and an injection volume of 0.8 mL/kg. Images of group A were obtained with 120 kVp and filtered back projection (FBP) reconstruction, whereas images of group B were obtained with 80 kVp and 80% adaptive iterative statistical reconstruction algorithm (ASiR). The CT values and standard deviations of intracranial arteries and image noise on the corona radiata were measured to calculate the contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). The beam-hardening artifacts (BHAs) around the skull base were calculated. Two readers evaluated the image quality with volume rendered images using scores from 1 to 5. The values between the two groups were statistically compared. Results The mean CT value of the intracranial arteries in group B was significantly higher than that in group A (P 〈 0.001). The CNR and SNR values in group B were also statistically higher than those in group A (P 〈 0.001). Image noise and BHAs were not significantly different between the two groups. The image quality score of VR images of in group B was significantly higher than that in group A (P = 0.001). However, the quality scores of axial enhancement images in group B became significantly smaller than those in group A (P〈 0.001). The CT dose index volume and dose-length product were decreased by 63.8% and 64%, respectively, in group B (P 〈 0.001 for both). Conclusion Visipaque combined with 80 kVp and 80% ASiR provided similar image quality in intracranial CTA with 64% radiation dose reduction compared with the use of lopamidol, 120 kVp, and FBP reconstruc-tion. 展开更多
关键词 low concentration contrast medium head and neck computed tomography angiography adaptive iterative statistical reconstruction algorithm
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Isolation and Identification of an Insecticidal Compound from Streptomyces sp. HBUM 174093
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作者 Nan SHI jinhua zhang +2 位作者 Hongxing CAI Liping zhang Yunlong ZHAO 《Agricultural Biotechnology》 CAS 2014年第3期53-55,共3页
[Objective]This study aimed to isolate and identify the insecticidal compound produced by the Streptomyces strain.[Method]Extraction,PTLC,HPLC,and other instrumental analysis were applied to obtain the bioactive compo... [Objective]This study aimed to isolate and identify the insecticidal compound produced by the Streptomyces strain.[Method]Extraction,PTLC,HPLC,and other instrumental analysis were applied to obtain the bioactive compound.[Result]Yellow-white crystals were obtained and their MS and NMR spectra were analyzed.[Conclusion]Crystals were identified as the analogue of dimeric dinactin. 展开更多
关键词 Insecticidal compound STREPTOMYCES Dimeric dinactin
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Expression of Tyrosine-kinase Receptors and Neurotrophins in Human Neuroblastomas
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作者 Daojian Rong Haicle Gao +3 位作者 jinhua zhang Xinyuan Li Xu Li Jihong zhang 《Chinese Journal of Clinical Oncology》 CSCD 2005年第6期852-855,共4页
OBJECTIVE The aim of this study was to investigate mRNA expression of tyrosine-kinase receptors (TRKs) and neurotrophins (NTs) in human neuroblastomas. METHODS Expression of TrkA, TrkB, TrkC and BDNF was quantitat... OBJECTIVE The aim of this study was to investigate mRNA expression of tyrosine-kinase receptors (TRKs) and neurotrophins (NTs) in human neuroblastomas. METHODS Expression of TrkA, TrkB, TrkC and BDNF was quantitatively examined by reverse transcription-polymerase chain reaction (RT-PCR) in 27 cases of neuroblastomas. RESULTS The high and total rates of TrkA were expressed in significantly more tumors in a lower-stage group compared to a higher-stage group (P〈0.05) and the high level of TrkA expression was correlated positively with the 2-year cumulative-survival rate of the patients (P〈 0.01). The high and total rates of TrkB were expressed in significantly more tumors in a higher-stage group compared to a lower-stage group (P〈0.05). All 3 rates of BDNF expression between the 2 groups showed no statistical difference (P〉0.05), but the co-expression ratio of TrkB and BDNF showed a remarkable significance in the higher-stage group more than in the lower-stage group (P〈0.05). TrkC expression was usually accompanied by TrkA expression, but there was only a non-significant trend between TrkC expression and TrkA expression. CONCLUSION RT-PCR for mRNA expression of TRKs and NTs has important clinical significance relating to the tumor stage and outcome for patients with neuroblastomas. 展开更多
关键词 NEUROBLASTOMA tyrosine-kinase receptor NEUROTROPHIN RTPCR.
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Numerical Investigation on Flow Pattern of Air-Oil with Different Viscosities Lubrication
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作者 Qunfeng Zeng jinhua zhang +1 位作者 Jun Hong Wenjun Su 《Engineering(科研)》 2017年第1期1-13,共13页
In the present work, the performance of oil-air two-phase flow under different lubricant oils was investigated. The simulation method was applied to study the influence of the oil viscosity on the flow pattern, veloci... In the present work, the performance of oil-air two-phase flow under different lubricant oils was investigated. The simulation method was applied to study the influence of the oil viscosity on the flow pattern, velocity distribution and Re number in oil-air lubrication by FLUENT software with VOF model to acquire the working performance of oil-air lubrication for high-speed ball bearing. This method was used to obtain the optimum lubrication conditions of high-speed ball bearing. The optimum operating conditions that produce the optimum flow pattern were provided. The optimum annular flow was obtained by PAO6 oil with the low viscosity. Reynolds number influences the fluid shape and distribution of oil and air in pipe. The annular flow can be formed when Reynolds number is an appropriate value. The velocity distribution of oil-air two-phase flow at outlet was also discussed by different oil viscosities. The simulating results show that due to the effect of the oil viscosity and flow pattern the velocity decreased and expanded gradually close to the pipe wall, and the velocity increased close to the central pipe. The simulation results provide the proposal for the design and operation of oil-air two-phase flow lubrication experiments in the present work. This work provides a useful method in designing oil-air lubrication with the optimum flow pattern and the optimum operating conditions. 展开更多
关键词 Oil-Air LUBRICATION FLOW Pattern Two-Phase FLOW ANNULAR FLOW
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Water Quality Analysis of Fuping Section of the Shichuan River Based on Different Evaluation Methods
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作者 Xiaoyan WANG jinhua zhang +2 位作者 Jing WANG Yating PANG Pei zhang 《Meteorological and Environmental Research》 CAS 2022年第6期63-67,共5页
In order to study the water quality of the Shichuan River basin in Fuping,Shaanxi Province,based on improved Nemerow index method,comprehensive pollution index method and principal component analysis method,eight wate... In order to study the water quality of the Shichuan River basin in Fuping,Shaanxi Province,based on improved Nemerow index method,comprehensive pollution index method and principal component analysis method,eight water quality indexes such as pH,dissolved oxygen(DO),total dissolved solids(TDS),COD,total hardness,total phosphorus,total nitrogen and Zn in three monitoring sections of Fuping section of the Shichuan River in Shaanxi Province were detected and analyzed.The results show that the water quality of the surface water in the Shichuan River basin is gradeⅢorⅣwater,that is,the water is slightly polluted and moderately polluted.It is necessary to monitor the water quality after regulation and clarify the main factors causing the water pollution. 展开更多
关键词 Water quality evaluation Improved Nemero index method Comprehensive pollution index method Principal component analysis Shichuan River
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Partial aging can counter-intuitively couple with sulfidation to improve the reactive durability of zerovalent iron
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作者 Yiwei Liu Kaili Gu +4 位作者 jinhua zhang Jinxiang Li Jieshu Qian Jinyou Shen Xiaohong Guan 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第2期1-11,共11页
Sulfated zero-valent iron(SZVI)has shown promising applications in wastewater treatment.However,the rapid decline in the reactivity of SZVI with time limits its real practice.To mediate this problem,partial aging was ... Sulfated zero-valent iron(SZVI)has shown promising applications in wastewater treatment.However,the rapid decline in the reactivity of SZVI with time limits its real practice.To mediate this problem,partial aging was proposed to improve the reactive durability of SZVI.Taking Cr(VI)as the target contaminant,we found that the aged ZVI(AZVI)gradually lost reactivity as aging time increased from 0.5 to 2 d.Counter-intuitively,the partially aged SZVI(ASZVI)showed greater reactivity than SZVI when exposed to oxygenated water for a period ranging from 0.5 to 14 d.In addition,the ASZVI with 0.5 d of aging time(ASZVI-0.5)not only maintained reactivity in successive runs but also increased the Cr(VI)removal capacity from 9.1 mg/g by SZVI to 19.1 mg/g by ASZVI-0.5.Correlation analysis further revealed that the electron transfer from the Fe0 core to the shell was mediated by the conductive FeS and FeS2 in the subshell of ASZVI.Meanwhile,the lepidocrocite and magnetite on the surface of ASZVI facilitated Cr(VI)adsorption and subsequent electron transfer for Cr(VI)reduction.Moreover,the iron(hydr)oxide shell could retain the conductive FeS and FeS2 in the subshell,allowing ASZVI to reduce Cr(VI)efficiently and sustainably.In general,partial aging can enhance the reactive durability of ZVI when coupled with sulfidation and this synergistic effect will be beneficial to the application of SZVI-based technology for wastewater treatment. 展开更多
关键词 Zerovalent iron SULFIDATION Partial aging Interface reconstruction Electron transfer
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基于劈裂环的光学天线研究
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作者 张锦华 张益华 田汶翔 《建模与仿真》 2024年第4期4558-4565,共8页
光学天线是一个新兴领域,可以与自由空间电磁波发生相互作用,把光场限制在亚波长的尺寸,促使天线狭缝处电场的局域增强。光学天线的提出使得在亚波长尺寸下调控光场成为可能,在光学成像、光学传感、纳米光学等领域具有广泛的应用。本文... 光学天线是一个新兴领域,可以与自由空间电磁波发生相互作用,把光场限制在亚波长的尺寸,促使天线狭缝处电场的局域增强。光学天线的提出使得在亚波长尺寸下调控光场成为可能,在光学成像、光学传感、纳米光学等领域具有广泛的应用。本文将对劈裂环天线进行深入研究,在电场作用下劈裂环将产生两种共振模式,分别是低频的电感–电容(LC)共振和高频的偶极共振,在天线表面形成环形振荡电流和线性振荡电流。两种共振模式可以很好地实现电场局域增强。 展开更多
关键词 光学天线 劈裂环 LC共振 偶极共振 电场局域增强
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Effects of different protein and lipid levels on the growth performance and intestinal microflora of loach(Paramisgurnus dabryanus) 被引量:1
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作者 Zirui Wang Shuyao Li +5 位作者 Qiubai Zhou jinhua zhang Yongan Li Youjie Li Zhiwen Yuan Guanghua Huang 《Animal Nutrition》 SCIE CAS CSCD 2023年第2期229-239,共11页
The aim of this study was to examine the effects of dietary protein and lipid levels on the growth per-formance and homeostasis of the intestinal flora in Paramisgurnus dabryanus.An 8-week 3×3 two-factorial exper... The aim of this study was to examine the effects of dietary protein and lipid levels on the growth per-formance and homeostasis of the intestinal flora in Paramisgurnus dabryanus.An 8-week 3×3 two-factorial experiment was conducted to investigate the interaction between dietary crude protein(CP:30%,35%,40%)and ether extract(EE:6%,10%,14%)on the growth rate and the intestinal microflora of P.dabryanus.A total of 2,160 fish(5.19±0.01 g)were randomly allotted to 36 aquariums each with 60 fish.Fish were fed the experimental diet twice daily.Results revealed that weight gain rate(WGR),specific growth rate(SGR),protein efficiency ratio and net protein utilization significantly increased when increasing protein levels from 30%to 40%(P<0.05).Both WGR and SGR enhanced first but reduced thereafter with maximum value at 10%lipid level as dietary lipid increased from 6%to 14%(P<0.05).Significant interactions between protein and lipid were found with feed conversion rate,lipid efficiency ratio and net lipid utilization(P<0.05).At the phylum level,Proteobacteria and Actinobacteria were the dominant bacteria;at the genus level,Burkholderia-Caballeronia-Paraburkholderia was the dominant bacteria.Fish fed the diet containing 10%lipid had a higher abundance of Proteobacteria and unclassi-fied_f_Eenterobacteriaceae than those fed the 14%lipid diet,and a higher abundance of Rhodobacter than those fed the 6%lipid diet(P<0.05).Analysis of the predicted functions showed that metabolism in the intestine of fish in the CP40EE10 group was more active than that in CP30EE14 group.Polynomial regression analysis found that a diet containing 40.87%protein and 9.88%lipid can be considered optimal for P.dabryanus. 展开更多
关键词 Paramisgurnus dabryanus Protein/lipid ratio Growth performance Feed utilization Intestinal microflora
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MyD88 in macrophages protects against colitis via inhibiting the activation of NLRP3 inflammasome in epithelial cells 被引量:1
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作者 Shi Liu Yanmin Wu +6 位作者 Haiqiang Chen Qi Yuan Shuang Ge Lishu zhang Lingling Hou Tian Tian jinhua zhang 《Genes & Diseases》 SCIE CSCD 2023年第2期344-347,共4页
The signal adaptor myeloid differentiation primary response 88(MyD88)of Toll-like receptor(TLR)signaling is universally expressed in immune cells and non-immune cells,and myeloid cells play a significant role in modul... The signal adaptor myeloid differentiation primary response 88(MyD88)of Toll-like receptor(TLR)signaling is universally expressed in immune cells and non-immune cells,and myeloid cells play a significant role in modulating colitis.Macrophages are myeloid lineage cells which is important for maintaining intestinal homeostasis in inflammation.1 And macrophages can recognize invading pathogens through pattern recognition receptors(PRRs),such as TLRs and the nucleotide oligomerization domain(NOD)-like receptor family,pyrin domain-containing 3(NLRP3),and quickly infiltrate the injured site leading to inflammation.2 MyD88 expression in myeloid cells can rescue the intestinal injury induced by dextran sulfate sodium(DSS)in murine models.However,the mechanism whereby MyD88 works in myeloid cells and influence the progress of the disease remain elusive.In this study,we used DSS induced colitis mouse model and found Lysm-cre-MyD88fl/fl(MyD88ΔМΦ)mice were more susceptible to colitis.The deficiency of MyD88 leads to up-regulation of S100A8,which activate NLRP3 inflammasome and their associated pyroptosis in intestinal epithelial cells in a RAGE dependent manner.Thus,MyD88 signaling in macrophages,which is necessary to maintain intestinal homeostasis,crucially prevents the development of colitis.Our results may shed new lights on potential targets that can be applied in colitis therapy. 展开更多
关键词 NLRP3 COLITIS HOMEOSTASIS
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硫化零价铁去除水中污染物的效能及交互机制 被引量:6
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作者 顾凯丽 李浩贞 +1 位作者 张晋华 李锦祥 《化学进展》 SCIE CAS CSCD 北大核心 2021年第10期1812-1822,共11页
如何同步提升零价铁去除水中污染物的反应速率和电子选择性已成为近年研究热点。基于无氧体系下硫化能通过抑制零价铁与水之间的副反应而改善体系还原除污染物效能,系统概括了不同硫化方式、硫化药剂和硫化程度合成的硫化零价铁理化特征... 如何同步提升零价铁去除水中污染物的反应速率和电子选择性已成为近年研究热点。基于无氧体系下硫化能通过抑制零价铁与水之间的副反应而改善体系还原除污染物效能,系统概括了不同硫化方式、硫化药剂和硫化程度合成的硫化零价铁理化特征,并揭示了其与硫化零价铁在不同水氧环境下去除不同污染物反应活性和电子选择性的交互机制。硫化能够主要通过调控界面亲疏水和导电性能而实现改善零价铁除污染的效能,其提升表现主要依赖于硫化程度,而与硫化方式、硫化药剂相关性较低。最后,展望了基于硫化零价铁的水污染控制技术在地下水修复和工业废水处理的应用前景。 展开更多
关键词 硫化 零价铁 反应活性 电子选择性 理化特征
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