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Emergent vegetation flow with varying vertical porosity

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Journal of Hydrodynamics 2019年第5期31卷 1043-1051页

作者： Ming-deng zhao Zi-long fan State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Department of Engineering and Information Technology China International Water and Electric Corporation(CWE)Beijing 100120China China Three Gorges Corporation(CTG) Beijing J 00038China

The vertical distribution of an emergent vegetation in wetlands and marshes is generally non-uniform due to the variations of the stem thickness and the leaf *** study focuses on the effect of the varying vertical porosity on the hydrodynamic characteristics of the emergent vegetation *** new governing equation for the emergent vegetation flow with varying vertical porosity is established by applying the poroelastic media flow *** to the movement mechanism of the water flow in the porous media and the experimental data,the best fitted expression of the permeability is established for the emergent vegetation *** velocity distribution is obtained with the finite analytic ***,a flume experiment is performed using truncated cones to simulate the actual vegetation with varying vertical *** calculated velocity distribution is compared with the measured data,which shows that the theoretical results are in good agreement with the experimental ***,the influence of the vertical porosity distribution on the vegetation flow characteristics is analyzed *** study can provide a useful reference and technical support for further study of the flow with a complex shape vegetation.

关键词： Emergent vegetation flow velocity distribution varying vertical porosity finite analytic method Biot^poroelastic theory

A novel phenomenological model using a sine function for finite-element simulation of large-strain hot deformation

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Science China(Technological Sciences) 2018年第5期61卷 748-760页

作者： ZENG fan HU ChengLiang zhao Zhen Institute of Forming Technology & Equipment Shanghai Jiao Tong University

In hot deformation, the flow stress curves of steels always present as two typical types: at relatively high temperature and low strain rate, the flow stress may first increase and then attain a steady value without reaching an obvious peak stress; in other situations, the flow stress decreases after reaching peak stress and then attains a steady value. A new phenomenological model,described by a sine-function equation, is proposed to define the relationship between flow stress and deformation parameters. A series of isothermal compressions for a carbon steel were carried out, as a case study, to obtain basic experimental *** of the new model were sequentially determined. The predicted results of the proposed model were compared with actual measured data. Good accuracy was found in the standard statistical parameters of correlation coefficient, root mean square error, and average absolute relative error with the values of 0.935, 7.137 MPa and 4.352%, respectively. Discussion of applications of different models in finite-element simulation demonstrated the benefit of the new model. When comparing the simulation results of three different deformation patterns with large strain, the new model showed 10%–20% lower predicted forming load than the original Arrhenius equation, and better applicability and reliability than modified Arrhenius equations.

关键词： phenomenological model high temperature large strain finite-element simulation

Rac1 Signaling in Amygdala Astrocytes Regulates Fear Memory Acquisition and Retrieval

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Neuroscience Bulletin 2021年第7期37卷 947-958页

作者： Xiao-Cen fan Chao-Nan Ma Jia-Chen Song zhao-Hui Liao Nan Huang xing Liu Lan Ma Department of Neurosurgery Huashan HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceSchool of Basic Medical SciencesInstitutes of Brain ScienceFudan UniversityShanghai 200032China

The importance of astrocytes in behavior control is increasingly appreciated,but little is known about the effects of their dynamic activity in regulating learning and *** the present study,we constructed AAVs of photoactivatable and photoinactivatable Ras-related C3 botulinum toxin substrate 1(Rac1)under the mGFAP promoter,which enabled the manipulation of Rac1 activity in astrocytes by optical stimulation in free-moving *** found that both up-regulation and down-regulation of astrocytic Rac1 activity in the basolateral amygdala(BLA)attenuated memory acquisition in a fear conditioning mouse ***,neuronal activation in the BLA induced by memory acquisition was inhibited under both the up-and down-regulation of astrocytic Rac1 activity during *** terms of the impact on fear memory retrieval,we found both up-and down-regulation of BLA astrocytic Rac1 activity impaired memory retrieval of fear conditioning and memory retrieval-induced neuronal ***,the effect of astrocytic Rac1 on memory retrieval was *** results demonstrate that the normal activity of astrocytic Rac1 is necessary for the activation of neurons and memory *** activation and inactivation of astrocytic Rac1 activity in the BLA reduced the excitability of neurons,and thereby impaired fear memory acquisition and retrieval.

关键词： Rac1 Astrocyte Neuron BLA Fear memory

Variation of the Vaginal Microbiome During and After Pregnancy in Chinese Women

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Genomics, Proteomics & Bioinformatics 2022年第2期20卷 322-333页

作者： Xiaoai Zhang Qingzhi Zhai Jinfeng Wang Xiuling Ma Bo xing Hang fan Zhiying Gao fangqing zhao Wei Liu State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijing 100071China Department of Obstetrics and Gynecology First Medical CenterThe General Hospital of the People’s Liberation ArmyBeijing 100853China Computational Genomics Lab Beijing Institutes of Life ScienceChinese Academy of SciencesBeijing 100101China Beijing Key Laboratory of Vector Borne and Natural Focus Infectious Disease Beijing 100071China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming 650223China Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesChinese Academy of SciencesHangzhou 310024China University of Chinese Academy of Sciences Beijing 100049China

A comprehensive profiling of the vaginal microbial communities and their variability enables an accurate description of the microbiome in ***,there is a lack of studies available on Chinese *** the present study,the composition of the vaginal microbiota during pregnancy and the 6-week postpartum period of 454 Chinese women was characterized by sequencing the V3-V4 region of the 16S ribosomal RNA(rRNA)*** vaginal microbiome showed variations during pregnancy and the postpartum period based on the abortion history,hypertensive disorders,delivery mode,and maternal ***-variation of 22 bacterial taxa,including the Lactobacillus genus and two of its species,may account for the common characteristics of the vaginal microbiome under scenarios of different medical histories and pregnancy *** contrast,discriminant bacterial species were significantly different between women who had preterm birth(PTB)with and without premature rupture of membranes(PROM),and the community state type(CST)IV-A without any predominant Lactobacillus species in the microbiota was more prevalent during pregnancy in the PROM-PTB cases,suggesting that specific bacterial species could be considered to distinguish between different types of *** providing data on Chinese women,this study will enrich the knowledge of the human microbiome and contribute to a better understanding of the association between the vaginal microbiome and reproductive health.

关键词： Chinese pregnant women Vaginal microbiota Postpartum Pregnancy complication Premature rupture of membranes Preterm birth

感染暴发性流行病病毒的中国对虾形态学研究 3.病虾鳃的显微与超微结构

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山东大学学报（理学版） 2002年第5期37卷 458-462页

作者：刘昌彬张红卫王金星毕祖刚吕丽华赵兴范张荣芝山东大学生命学院济南250100 威海水产研究所威海264400 济南水利局济南250014 菏泽水产局菏泽274000

在光镜和透射电镜下 ,观察经实验感染暴发性流行病病毒中国对虾的鳃组织 ,发现鳃丝扁平上皮细胞及少量的网状隔膜细胞被感染而引起血隙狭小 ,以及巨噬细胞样无颗粒细胞的趋化作用导致鳃丝扁平上皮细胞增厚而影响其代谢功能 .另外 ,还观... 详细信息

在光镜和透射电镜下 ,观察经实验感染暴发性流行病病毒中国对虾的鳃组织 ,发现鳃丝扁平上皮细胞及少量的网状隔膜细胞被感染而引起血隙狭小 ,以及巨噬细胞样无颗粒细胞的趋化作用导致鳃丝扁平上皮细胞增厚而影响其代谢功能 .另外 ,还观察到巨噬细胞样无颗粒细胞有强烈的吞噬作用 .小颗粒细胞也具吞噬作用 ,在染色质凝聚结构等刺激下胞吐小颗粒 .大颗粒细胞也具有胞吐大颗粒功能 .与上述无颗粒细胞相比 ,胃结缔组织血窦内的浆细胞样无颗粒细胞其释放物与病毒结合参与体液免疫 .

关键词：形态学暴发性流行病超微结构鳃中国对虾病毒感染显微结构

抗棉铃虫组织蛋白酶B单克隆抗体的制备及鉴定

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山东大学学报（理学版） 2004年第6期39卷 116-120页

作者：杨晓梅侯立静康翠洁邵红莲张新昌杜欣军王金星赵小凡山东大学生命科学学院山东济南250100

分别以棉铃虫组织表达的组织蛋白酶B和基因重组的大肠杆菌表达的组织蛋白酶B为抗原免疫BALB c小鼠 ,选择血清抗体滴度高的免疫小鼠 ,取其脾细胞和Sp2 0骨髓瘤细胞进行细胞融合 .经ELISA法筛选阳性克隆和有限稀释法克隆细胞 ,共获得分... 详细信息

分别以棉铃虫组织表达的组织蛋白酶B和基因重组的大肠杆菌表达的组织蛋白酶B为抗原免疫BALB c小鼠 ,选择血清抗体滴度高的免疫小鼠 ,取其脾细胞和Sp2 0骨髓瘤细胞进行细胞融合 .经ELISA法筛选阳性克隆和有限稀释法克隆细胞 ,共获得分泌抗组织蛋白酶B的单克隆抗体杂交瘤细胞 3株 ,分别命名为 9D5 ,10 0E2和10 0H6 .以ELISA法和Westernblotting法对 3株杂交瘤细胞株分泌的单克隆抗体进行了特异性鉴定 ,其中 9D5和10 0E2能够同时识别两种不同来源的组织蛋白酶B ,而 10 0H6只能识别基因重组的大肠杆菌表达的组织蛋白酶B .

关键词：棉铃虫组织蛋白酶B 单克隆抗体 ELISA Westem blotting

Dietary L-theanine alleviated lipopolysaccharide-induced immunological stress in yellow-feathered broilers

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Animal Nutrition 2018年第3期4卷 265-272页

作者： Rui Li Zehe Song Jianfei zhao Dongxiao Huo Zhiyong fan De-xing Hou Xi He College of Animal Science and Technology Hunan Agricultural University Hunan Co-Innovation Center of Animal Production Safety Department of Food Science and Biotechnology Faculty of Agriculture Kagoshima University

L-theanine, a natural nonprotein amino acid with a high biological activity, is reported to exert anti-stress properties. An experiment with a 3 ? 2 factorial arrangement was conducted to investigate the effects of dietary L-theanine on growth performance and immune function in lipopolysaccharide(LPS)-challenged broilers. A total of 432 one-day-old male yellow-feathered broilers were randomly assigned to 3 dietary treatments(control, antibiotic and L-theanine diets) with 2 subgroups of each(6 replicate cages;12 birds/cage). Birds from each subgroup of the 3 dietary treatments were intra-abdominally injected with the same amount of LPS or saline at 24, 25, 26 d of age. Both dietary L-theanine and antibiotic improved(P < 0.05) the growth performance of birds before LPS injection(d 1 to 21). The effect of dietary L-theanine was better(P < 0.05) than that of antibiotic. Lipopolysaccharide decreased feed intake(FI) and body weight gain(BWG) from d 22 to 28(P < 0.05), BWG and feed to gain ratio(F:G) from d 29 to 56(P < 0.05), increased mortality in different growth periods(P < 0.05), elevated the levels of serum cortisol, a1-acid glycoprotein(a1-AGP), interleukin-6(IL-6) on d 24 and 25(P < 0.05), reduced immune organ indexes and contents of jejunal mucosal secretory immunoglobulin A(s Ig A) on d 28(P < 0.05). The decreased FI and BWG, as well as increased F:G and mortality in LPS-challenged birds, were alleviated by dietary L-theanine or antibiotic from d 29 to 56 and from d 1 to 56. Dietary L-theanine mitigated the elevated serum a1-AGP level on d 25, serum IL-6 concentration on d 24 and 26, and the decreased jejunal mucosal s Ig A content on d 28 of the LPS-challenged birds. The results indicated that L-theanine had potential to alleviate LPS-induced immune stress in broilers.

关键词： L-theanine Yellow-feathered broilers Lipopolysaccharide Immune stress Growth performance

A Light Weight Traffic Volume Prediction Approach Based on Finite Traffic Volume Data

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 603-622页

作者： xing Su Minghui fan Zhi Cai Qing Liu Xiaojun Zhang Faculty of Information Technology Bering University of TechnologyBeijing100124China Shanghai Ocean University Shanghai201306China Academy of Opto-electronics Chinese Academy of SciencesBeijing100094China

As one of the key technologies of intelligent transportation systems, short-term traffic volume prediction plays an increasingly important role in solving urban traffic problems. In the last decade, many approaches were proposed for the traffic volume prediction from different perspectives. However, most of these approaches are based on a large amount of historical data. When there are only finite collected traffic data, they cannot be well trained, so the prediction accuracy of these approaches will be poor. In this paper, a tensor model is proposed to capture the change patterns of continuous traffic volumes. From collected traffic volume data, the element data are extracted to update the corresponding elements of the tensor model. Then, a tucker decomposition and gradient descent based algorithm is employed to impute the missing elements of the tensor model. After missing element imputation, the tensor model can be directly applied to the short-term traffic volume prediction through searching the corresponding elements of the model and the storage cost of the model is low. Our model is evaluated on real traffic volume data from PeMS dataset, which indicates that our model has higher traffic volume prediction accuracy than other approaches in the situation of finite traffic volume data.

关键词： Short-term traffic volume prediction tensor Tucker decomposition finite traffic volume data

Actin nucleator formins regulate the tension-buffering function of caveolin-1

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Journal of Molecular Cell Biology 2021年第12期13卷 876-888页

作者： Xuemeng Shi Daijiao Tang Yifan xing Shuangshuang zhao Changyuan fan Jin Zhong Yanqin Cui Kun Shi Yaming Jiu The Joint Program in Infection and Immunity Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhou 510623China The Joint Program in Infection and Immunity Institut Pasteur of ShanghaiChinese Academy of SciencesShanghai 200031China Unit of Cell Biology and Imaging Study of Pathogen Host Interaction The Center for MicrobesDevelopment and HealthCAS Key Laboratory of Molecular Virology and ImmunologyInstitut Pasteur of ShanghaiChinese Academy of SciencesShanghai 200031China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Unit of Viral Hepatitis CAS Key Laboratory of Molecular VirologyInstitut Pasteur of ShanghaiChinese Academy of SciencesShanghai 200031China

Both the mechanosensitive actin cytoskeleton and caveolae contribute to active processes such as cell migration,morphogenesis,and vesicular *** distinct actin components are well studied,how they contribute to cytoplasmic caveolae,especially in the context of mechano-stress,has remained ***,we identify two actin-associated mobility stereotypes of caveolin-1(CAV-1)-marked intracellular vesicles,which are characterized as‘dwelling’and‘go and dwelling’.In order to exploit the reason for their distinct dynamics,elongated actin-associated formin functions are *** find drastically decreased density,increased clustering,and compromised motility of cytoplasmic CAV-1 vesicles resulting from lacking actin nucleator formins by both chemical treatment and RNA silencing of formin ***,hypo-osmosis-stimulated diminishing of CAV-1 is dramatically intensified upon blocking *** clustering of CAV-1 vesicles when cells are cultured on soft substrate is also aggravated under formin inhibition ***,we reveal that actin-associated formins are essential for maintaining the dynamic organization of cytoplasmic CAV-1 and importantly its sensitivity upon mechanical *** conclude that tension-controlled actin formins act as a safety valve dampening excessive tension on CAV-1 and safeguarding CAV-1 against mechanical damage.

关键词： caveolin-1 elongated actin filaments formins hypo-osmotic shock matrix stiffness