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Physics of multiple level hairpin vortex structures in turbulence

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Science China(Physics,Mechanics & Astronomy) 2016年第2期59卷 91-101页

作者： Yi Qian Wang Hassan Al-Dujaly yong hua yan Ning Zhao Chao Qun Liu Department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Mathematics University of Texas at Arlington Arlington 76019 USA

Previous experimental and numerical studies have revealed that the hairpin vortex is a basic flow element of transitional boundary layer. The hairpin vortex is believed to have legs, necks and a ring head. Based on our DNS study, the legs and the ring head are generated separately by different mechanisms. The legs function like an engine to generate low speed zones by rotation, create shear layers with surrounding high speed neighbor fluids, and further cause vortex ring formation through shear layer instability. In addition, the ring head is Ω-shaped and separated from quasi-streamwise legs from the beginning. Contrary to the classical concept of ＂vortex breakdown＂, we believe transition from laminar flow to turbulence is a ＂buildup＂ process of multiple level vortical structures. The vortex tings of first level hairpins are mostly responsible for positive spikes, which cause new vorticity rollup, second level vortex leg formation and finally smaller second level vortex ring generation. The third and lower level vortices are generated following the same mechanism. In this paper, the physical process from A-vortex to mul- ti-level hairpin vortices is described in detail.

关键词： hairpin vortex vortex buildup multiple level vortices flow transition

Erythropoietin Receptor Gene (EPOR) Polymorphisms are Associated with Sow Litter Sizes

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Agricultural Sciences in China 2011年第6期10卷 931-937页

作者： ZHANG Long-chao WANG Li-gang LI yong yan hua ZHAO Ke-bin WANG Li-xian Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R. China

The erythropoietin receptor （EPOR） has shown to play an important role in fetal survival by promoting the maturation of red blood cells in many studies of uterine capacity and litter size in swine. In this study, we screened the porcine EPOR gene for mutations and identified five single nucleotide polymorphisms （SNPs）： g.705G〉T in intron 1, g.2 373C〉T in intron 4, and g.2 882C〉T, g.3 035A〉G, and g.3 132A〉T in intron 6. We then genotyped 247 Beijing Black （BB） sows and compared the polymorphism data with the litter sizes of 1 375 parities among the sows. At first parity, there was no association of g.2 882C〉T and g.3 132A〉T with litter sizes. However, the CT sows in g.2 882C〉T had 2.13 higher total number born （TNB）（P〈0.01） and 1.81 higher number born alive （NBA）（P〈0.01） than the CC sows and the heterozygous sows in g.3 132A〉T had the highest litter size when compared to the two homozygotes for the later parities （P〈0.05）. In the g.3 035A〉G SNP, for the later parities, the TNB of the sows with the GG genotype was 3.81 higher （P〈0.01） and the NBA was 2.75 higher （P〈0.01） than that with the AA genotype but no difference at first parity. The G allele of the EPOR g.705G〉T SNP was associated with a greater litter size at both the first parity （P〈0.05） and later parities （P〈0.01）. Furthermore, we determined the allele frequencies for this SNP among five Chinese indigenous pig breeds （Erhualian, Laiwu Black, Meishan, Min, and Rongchang） and three western commercial pig breeds （Duroc, Landrace, and Large White）. The G allele of the EPOR g.705G〉T SNP was significantly more common in the more prolific Chinese breeds. These results indicated that the EPOR could be an important candidate gene for litter size and g.705G〉T can serve as a useful genetic marker for improving litter size in both first and later parities in swine.

关键词： erythropoietin receptor litter size pig single nucleotide polymorphism

Design and simulation about a self-Tuning fuzzy-PID controller

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重庆邮电大学学报（自然科学版） 2009年第2期21卷 192-195,227页

作者： ZHANG Yi FU Wen-yong LI yan-hua DENG Hao-wen LIU Hong-chang Research Center of Intelligent System and Robotics Chongqing University of Posts and Telecommunications Chongqing 400065 P. R. China

Fuzzy logic has attracted the attention of structural control engineers during the last few years,because fuzzy logic can handle nonlinearities,uncertainties,and heuristic knowledge effectively and *** this paper,a self-Tuning fuzzy-PID control method which used the technology of the fuzzy control and PID control unified is *** techniques can visualize the results and processes for structure *** techniques will also provide convenience for engineers and users,and have high practical *** MATLAB simulation result shows that the system precision and the efficiency are very high and the static error is small,and robustness was also validated.

关键词： PID控制器模糊逻辑仿真结果自调整模糊PID控制设计 Matlab 启发式知识

Methyl Jasmonate Reduces Chilling Injury and Maintains Postharvest Quality in Peaches

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Agricultural Sciences in China 2003年第11期2卷 1246-1252页

作者： FENG Lei, ZHENG yong-hua, ZHANG yan-fen, WANG Feng ZHANG Lan and LU Zhao-xin(College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095 , P.R.China) College of Food Science and Technology Nanjing Agricultural University Nanjing 210095 P.R. China

Zhaohui peaches(Prunus persica Batsch)were treated with 0(CK), 1, 10 or 100 μmol L-1 methyl jasmonate(MeJA)vapor at 20℃ for 24 h before stored at 0℃ for 35 d. The untreated fruits showed chilling injury(CD symptoms after 4 wk of storage, as indicated by increased fruit firmness and reduced ex-tractable juice, which is referred as leatheriness. Treatment with 1 and 10 μmol L-1 MeJA promoted normal ripening and softening, maintained higher levels of extractable juice, titratable acidity, pectinesterase(PE)and polygalacturonase(PC)activities, inhibited increases in fruit fresh weight loss, decay incidence, electrolyte leakage and MDA content, and improved color development, thereby preventing chilling injury symptoms development and maintaining edible quality. MeJA treatment also delayed the climacteric rise in respiratory rate, but promoted ethylene production during the later period of cold storage, suggesting that ethylene may involve in CI development of peaches. These results indicate that 1 and 10 μmol L-1 MeJA treatments could be used to reduce CI development and decay incidence in peaches.

关键词： Peach fruit Chilling injury Leatheriness Quality Methyl jasmonate

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低温青藏高原土壤中镁合金阳极的电化学性能

材料科学与工艺 2008年第2期16卷 163-166页

作者：梁成浩袁传军勇艳华大连理工大学化工学院辽宁大连116012 大连海事大学机电与材料工程学院辽宁大连116026 大连民族学院辽宁大连116100

为评价低温土壤对镁合金阳极电化学性能的影响,通过极化曲线、交流阻抗和电流效率实验方法,研究了4种镁合金阳极在-4℃和4℃的模拟低温青藏高原土壤中的电化学性能.研究表明:镁合金中加入Mn、Al和Zn元素可与杂质元素形成阴极作用较弱的... 详细信息

为评价低温土壤对镁合金阳极电化学性能的影响,通过极化曲线、交流阻抗和电流效率实验方法,研究了4种镁合金阳极在-4℃和4℃的模拟低温青藏高原土壤中的电化学性能.研究表明:镁合金中加入Mn、Al和Zn元素可与杂质元素形成阴极作用较弱的金属间化合物,降低了镁合金的自溶解倾向,提高了电流效率;镁合金阳极在低温青藏高原土壤中呈活性溶解状态,溶解活性和反应活性由强到弱顺序为MGAZ63B镁合金、MGAZ31B镁合金、MGM1C镁合金和高纯镁;4种镁合金阳极中MGAZ63B的电流效率最高,-4℃和4℃时分别为54.39%和61.77%;4℃土壤中氧的扩散速率比-4℃时高,故镁合金阳极在青藏高原土壤中4℃时溶解活性和电流效率均优于-4℃时.

关键词：镁合金阳极低温土壤青藏冻土极化曲线交流阻抗

Error analysis for remote nonlinear iterative learning control system with wireless channel noise

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Journal of Shanghai University(English Edition) 2011年第1期15卷 7-11页

作者：方勇颜华超 Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information Engineering Shanghai University

In this paper, the iterative learning control problem is considered for a class of remote control system over wireless network communication channel. The control performance of remote iterative learning control （R-ILC） system is analyzed and an error boundary of the stable output of the R-ILC system is obtained for the boundary stochastic noise channel. Finally, we obtain some rules to reduce the fluctuation caused by wireless channel noise through the analysis results for fluctuation boundary. The simulation results prove the proposed rule is correct.

关键词： remote control system iterative learning control (ILC) stable convergence fluctuation boundary control performance

RGS4 promotes the progression of gastric cancer through the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition

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World Journal of Gastroenterology 2025年第2期31卷 113-127页

作者： Peng-Yu Chen Pei-Yao Wang Bang Liu yang-Pu Jia Zhao-Xiong Zhang Xin Liu Dao-Han Wang yong-Jia yan Wei-hua Fu Feng Zhu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Department of General Surgery Jincheng People’s HospitalJincheng 048000Shanxi ProvinceChina

BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G *** speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet *** To explore the role and underlying mechanisms of action of RGS4 in GC *** The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with *** assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in *** RGS4 was highly expressed in GC tissues compared with matched adjacent normal *** RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with *** experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and ***,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor ***,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase B,decreased vimentin and N-cadherin,and elevated *** High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic ***4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition.

关键词： Gastric cancer Prognosis Regulator of G protein signaling 4 Focal adhesion kinase Epithelial-mesenchymal transition

新疆典型盐生植物营养器官盐分积累与生态化学计量特征

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植物生态学报 2016年第12期40卷 1267-1275页

作者：雍艳华张霞王绍明吴玲石河子大学生命科学学院新疆石河子832003

对盐生植物体内器官盐分积累和碳(C)、氮(N)、磷(P)化学计量特征的研究,有助于了解盐生植物养分、盐分的分配机制和其对盐渍环境的适应策略。该文选择新疆4种典型的真盐生植物(3种灌木植物:盐节木(Halocnemum strobilaceum)、小叶碱蓬(S... 详细信息

对盐生植物体内器官盐分积累和碳(C)、氮(N)、磷(P)化学计量特征的研究,有助于了解盐生植物养分、盐分的分配机制和其对盐渍环境的适应策略。该文选择新疆4种典型的真盐生植物(3种灌木植物:盐节木(Halocnemum strobilaceum)、小叶碱蓬(Suaeda microphylla)、盐爪爪(Kalidium foliatum),1种草本植物:盐角草(Salicornia europaea)为研究对象,对比研究了它们的根、茎、叶中的盐分积累和C、N、P化学计量特征以及二者间的相关性。结果显示:1)在生长旺盛期,4种盐生植物体内盐分积累可形成"盐岛"效应(Na^+、Cl–和电导率随盐离子从植物根部向顶端运输过程呈显著增加的趋势)。2)4种盐生植物中灌木群落的生长主要受到P的限制;草本群落的生长受N和P(偏P)共同限制。3)器官、物种和二者的交互作用均能影响盐生植物的盐分(除Mg2^+外)特征和C、N、P生态化学计量特征。4)4种盐生植物C与N、P之间显著负相关,N与P之间显著正相关。5)盐生植物体内总盐分、Na^+和K^+与N、N:P之间呈显著正相关关系,与C、C:N、C:P之间呈显著负相关关系,而K^+和CO32–与P之间却显著正相关。盐生植物体内盐分和养分在应对盐渍环境上存在一定的相互促进关系,增施N肥有助于盐生植物对氯化物盐渍土的脱盐。这些发现为了解盐渍生境中盐生植物的生理生态适应及盐渍土的改良提供一定的理论依据。

关键词：生态化学计量学盐生植物盐离子碳氮磷真盐生植物

Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies

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Neural Regeneration Research 2025年第4期20卷 917-935页

作者： Dian Jiao Lai Xu Zhen Gu hua yan Dingding Shen Xiaosong Gu Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Key Laboratory of Advanced Drug Delivery Systems of Zhejiang Province College of Pharmaceutical SciencesZhejiang UniversityHangzhouZhejiang ProvinceChina Affiliated Hospital of Nantong University NantongJiangsu ProvinceChina

Epilepsy is a severe,relapsing,and multifactorial neurological *** regarding the accurate diagnosis,prognosis,and in-depth pathogenesis are crucial for the precise and effective treatment of *** pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression,protein expression,ion channel activity,energy metabolites,and gut microbiota *** results are lacking for conventional treatments for *** resection of lesions,drug therapy,and non-drug interventions are mainly used in clinical practice to treat pain associated with ***-pharmacological treatments,such as a ketogenic diet,gene therapy for nerve regeneration,and neural regulation,are currently areas of research *** review provides a comprehensive overview of the pathogenesis,diagnostic methods,and treatments of *** also elaborates on the theoretical basis,treatment modes,and effects of invasive nerve stimulation in neurotherapy,including percutaneous vagus nerve stimulation,deep brain electrical stimulation,repetitive nerve electrical stimulation,in addition to non-invasive transcranial magnetic stimulation and transcranial direct current *** studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic ***,many new technologies for the diagnosis and treatment of epilepsy are being ***,current research is mainly focused on analyzing patients’clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level,which has led to a lack of consensus regarding the mechanisms related to the disease.

关键词： diagnosis drug treatment electroencephalography epilepsy monitoring epilepsy nerve regeneration neurostimulation non-drug interventions pathogenesis prediction