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A revisit of the local scour around bridge piers under an ice-covered flow condition-An experimental study

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Journal of Hydrodynamics 2021年第5期33卷 928-937页

作者： Jun Wang Kui Wang bi-he Fang Jueyi Sui School of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China School of Engineering University of Northern British ColumbiaPrince GeorgeBCCanada

In this study,by changing both pier diameters and particle sizes of sand bed in flume experiments,the scour process around cylindrical bridge piers under an ice-covered flow condition has been *** is found that the appearance of an ice cover on the water surface caused a deeper and wider scour hole in comparison with that in an open flow with identical flow rates,implying a larger volume of scour hole under an ice-covered flow *** to the scouring process at a bridge pier under an open flow condition,both the depth and volume of a scour hole increase with the flow velocity and pier *** with results under an open flow condition,for identical flow rates,the maximum depth of a scour hole under an ice-covered flow condition increased by about 20%-30%,and both the scour area and volume of a scour hole increased by about 40%-50%.A flow at Froude number of 0.15 is the demarcation point for assessing an obvious impact of an ice cover on the local scour around a bridge pier in this experimental *** data collected from laboratory experiments,equations have been developed to calculate the maximum scour depth,scour area and scour *** of present study have been compared with those of others.

关键词： bridge pier ice cover local scour scour area scour depth scour volume

Microstructure evolution and hot deformation behavior of carbon nanotube reinforced 2009Al composite with bimodal grain structure

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Journal of Materials Science & Technology 2021年第11期70卷 73-82页

作者： K.Ma Z.Y.Liu S.bi X.X.Zhang b.L.Xiao Z.Y.Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang110016China School of Materials Science and Engineering Guilin University of TechnologyGuilin541004China

The hot deformation behaviors of the bimodal carbon nanotube reinforced 2009Al(CNT/2009Al)composite were studied by establishing processing map and characterizing the microstructure *** results indicate that the grain size in the ultra-fine grained zones was stable during hot deformation,while the coarse grained zones were elongated with their long axis directions tending to be perpendicular to the compression *** temperature with high strain rate(LTHR),as well as high temperature with low strain rate(HTLR)could increase the length/width ratio of the coarse grained ***,LTHR and HTLR could cause the instable *** instable deformation at LTHR was induced by severe intragranular plastic deformation and the localized shear crack,while the instable deformation at HTLR resulted from the more deformation component at the coarse grained zones,and the micro-pore initiation due to CNT re-agglomeration at the boundaries between the coarse and the ultra-fine grained zones.

关键词： Carbon nanotube bimodal Aluminum matrix composite Hot deformation Processing map

Mapping of Mutant Gene prbs Controlling Poly-Row-and-branched Spike in barley (Hordeum vulgare L.)

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Agricultural Sciences in China 2011年第10期10卷 1501-1505页

作者： HUANG bi-guang WU Wei-ren Key Laboratory for Genetics Breeding and Multiple Utilization of Crops Ministry of Education/College of Crop Science Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China

A row-type mutant of barley named poly-row-and-branched spike （prbs） was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRbS locus had a recessive epistatic effect on an independent locus （denoted as Vrsx） conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRbS as well as Vrsx using simple sequence repeats （SSR） markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type：six-rowed type：prbs=9：3：4 in the population, we adopted a special strategy to map the two loci. PRbS was mapped between SSR markers HvLTPPb and bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers bmag0125 and bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRbS is a new locus related to the row type of spikes in barley.

关键词： barley row type prbs mapping SSR

Targeting RAF dimers in RAS mutant tumors:From biology to clinic

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Acta Pharmaceutica Sinica b 2024年第5期14卷 1895-1923页

作者： Huanhuan Yin Qiulin Tang Hongwei Xia Feng bi Division of Abdominal Cancer Department of Medical OncologyCancer Center and Laboratory of Molecular Targeted Therapy in OncologyWest China HospitalSichuan UniversityChengdu 610041China

RAS mutations occur in approximately 30%of tumors worldwide and have a poor prognosis due to limited *** targeting of KRAS G12C has achieved significant success in recent years,but there is still a lack of efficient therapeutic approaches for tumors with non-G12C KRAS mutations.A highly promising approach is to target the MAPK pathway downstream of RAS,with a particular focus on RAF ***-generation RAF inhibitors have been authorized to treat bRAF mutant tumors for over a ***,their use in RAS-mutated tumors is not recommended due to the paradoxical ERK activation mainly caused by RAF *** address the issue of RAF dimerization,type II RAF inhibitors have emerged as leading *** clinical studies have shown the initial effectiveness of these agents against RAS mutant ***,type II RAF inhibitors in combination with MEK or ERK inhibitors have demonstrated impressive efficacy in RAS mutant *** review aims to clarify the importance of RAF dimerization in cellular signaling and resistance to treatment in tumors with RAS mutations,as well as recent progress in therapeutic approaches to address the problem of RAF dimerization in RAS mutant tumors.

关键词： RAS mutations RAF dimerization RAF inhibitors Cancer therapy Drug resistance

Stochastic frontiers or regression quantiles for estimating the self-thinning surface in higher dimensions?

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Journal of Forestry Research 2021年第4期32卷 1515-1533页

作者： Dechao Tian Huiquan bi Xingji Jin Fengri Li Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityNo.26 Hexing RoadHarbin 150040People’s Republic of China Forest Science NSW Department of Primary Industries−ForestryLevel 1210 Valentine AveParramattaNSW 2150Australia School of Ecosystem and Forest Sciences The University of MelbourneParkvilleVIC 3010Australia

Stochastic frontier analysis and quantile regression are the two econometric approaches that have been commonly adopted in the determination of the self-thinning boundary line or surface in two and higher dimensions since their introduction to the field some 20 years ***,the rational for using one method over the other has,in most cases,not been clearly explained perhaps due to a lack of adequate appreciation of differences between the two approaches for delineating the self-thinning *** an adequate understanding of such differences,the most informative analysis may become a missed opportunity,leading to an inefficient use of data,weak statistical inferences and a failure to gain greater insight into the dynamics of plant populations and forest stands that would otherwise be *** data from 170 plot measurements in even-aged Larix olgensis(***) plantations across a wide range of site qualities and with different abundances of woody weeds,*** regenerated non-crop species,in northeast China,this study compared the two methods in determining the self-thinning surface across eight sample sizes from 30 to 170 with an even interval of 20 observations and also over a range of quantiles through repeated random sampling and *** all sample sizes and over the quantile range of 0.90 ≤τ≤0.99,the normal-half normal stochastic frontier estimation proved to be superior to quantile regression in statistical *** parameter estimates had lower degrees of variability and correspondingly narrower confidence *** greater efficiency would naturally be conducive to making statistical *** estimated self-thinning surface using all 170 observations enveloped about 96.5% of the data points,a degree of envelopment equivalent to a regression quantile estimation with aτ of *** stochastic frontier estimation was also more objective because it did not involve the subjective selection of a particular value

关键词： Larix olgensis Normal-half normal distribution Site productivity Woody weeds Sample size Quantile selection

Sulphate attack resistance of high-performance concrete under compressive loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第7期14卷 459-468页

作者： Hui XU Yu-xi ZHAO Lei CUI bi XU Institute of Structural Engineering Zhejiang University School of Civil Engineering Newcastle University CCCC Tianjin Dredging Co. Ltd.

In this paper, an experimental study on the sulphate attack resistance of high-performance concrete (HPC) with two different water-to-binder ratios (w/b) under compressive loading is presented. The sulphate concentration, compressive strength, and the mass change in the HPC specimens were determined for immersion in a Na2SO4 solution over different durations under external compressive loading by self-regulating loading equipment. The effects of the compressive stress, the w/b ratio, and the Na2SO4 solution concentration on the HPC sulphate attack resistance under compressive loading were analysed. The results showed that the HPC sulphate attack resistance under compressive loading was closely related to the stress level, the w/b ratio, and the Na2SO4 solution concentration. Applying a 0.3 stress ratio for the compressive loading or reducing the w/b ratio clearly improved the HPC sulphate attack resistance, whereas applying a 0.6 stress ratio for the compressive loading or exposing the HPC to a more concentrated Na2SO4 solution accelerated the sulphate attack and HPC deterioration.

关键词： Sulphate attack resistance High-performance concrete (HPC) Compressive loading

MicroRNA negatively regulates NF-κb-mediated immune responses by targeting NOD1 in the teleost fish Miichthys miiuy

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Science China(Life Sciences) 2021年第5期64卷 803-815页

作者： Qing Chu Dekun bi Weiwei Zheng Tianjun Xu Laboratory of Fish Molecular Immunology College of Fisheries and Life ScienceShanghai Ocean UniversityShanghai 201306China Laboratory of Marine biology and biotechnology Qingdao Pilot National Laboratory for Marine Science and TechnologyQingdao 266071China Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China National Pathogen Collection Center for Aquatic Animals Shanghai Ocean UniversityShanghai 201306China

Inflammation is a self-protection mechanism that can be triggered when innate immune cells detect *** of pathogen infection requires appropriate immune and inflammatory responses,but excessive inflammatory responses can cause uncontrolled inflammation,autoimmune diseases,or pathogen *** evidence has shown that microRNAs(miRNAs)in mammals act as important and versatile regulators of innate immunity and ***,miRNAmediated regulation networks are largely unknown in inflammatory responses in lower ***,miR-144 and miR-217 are identified as negative regulators in teleost inflammatory *** find that Vibrio harveyi and lipopolysaccharide(LPS)treatment significantly upregulate the expression of fish miR-144 and *** miR-144 and miR-217 suppress LPS-induced inflammatory cytokine expression by targeting nucleotide-binding oligomerization domain-containing protein 1(NOD1),thereby avoiding excessive inflammatory *** addition,miR-144 and miR-217 regulate inflammatory responses through NOD1-induced nuclear factor kappa(NF-κb)signaling *** findings demonstrate that miR-144 and miR-217 play regulatory roles in inflammatory responses by modulating the NOD1-induced NF-κb signaling pathway.

关键词： microRNA negative regulation NF-κb NOD1 Miichthys miiuy

Nitrogen isotope stratigraphy of the Early Cambrian successions in the Tarim basin:Spatial variability of nitrogen cycling and its implication for paleo-oceanic redox conditions

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Acta Geochimica 2024年第4期43卷 785-801页

作者： bi Zhu Xuefeng Li Lu Ge Yongquan Chen Institute of Earth’s Critical Zone School of Earth Sciences and EngineeringHohai UniversityNanjing 210098China Research Institute of Exploration and Development Tarim Oil Field CompanyPetroChinaKorlaChina

The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in *** isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian *** existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses *** this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim basin,*** data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the Yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/*** is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major *** contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling *** the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen *** two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the Yurtus black rock *** spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean dur

关键词： Nitrogen isotopes Early Cambrian Tarim black rock series

PAI-1 Derived from Alveolar Type 2 Cells Drives Aging-Associated Pulmonary Fibrosis

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Engineering 2024年第11期42卷 74-87页

作者： Rui Quan Chenhong Shi Yanan Sun Chengying Zhang Ran bi Yiran Zhang Xin bi bin Liu Ziheng Dong Dekui Jin Yixuan Li Key Laboratory of Functional Dairy Co-Constructed by the Ministry of Education and Beijing MunicipalityBeijing 100083China Department of General Practice The Third Medical Center of the Chinese PLA General HospitalBeijing 100039China Department of Thoracic Surgery The Third Medical Center of the Chinese PLA General HospitalBeijing 100039China Center for Nanomedicine and Department of Anesthesiology Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA School of Computer and Information Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China

Pulmonary fibrosis(PF)is a lethal lung disease that predominantly affects older adults;however,whether and how aging triggers fibrosis remains *** pinpoint the predominant initiating factors of PF,we first analyzed single-cell RNA sequencing(scRNA-seq)data from the lung tissues of 45 normal donors and 51 PF patients and found that aging might serve as the primary catalyst for PF *** further investigate the influence of aging on PF formation,we conducted a comprehensive and thorough study employing a natural aging mouse *** found that dynamic alterations in the quantity and types of collagen fibers during aging-induced PF progression,especially in collagenous(Col)I,emerged as the predominant driver of *** then investigated the regulation of Col I synthesis during aging using primary alveolar type 2(AT2)cells and A549 cells line through conditioned media and Transwell cocul-ture,and found that secretions—particularly plasminogen activator inhibitor(PAI)-1—from aged AT2 cells promoted fibrosis and enhanced collagen type I alpha 1(Col1al)production via the transforming growth factor(TGF)-b/small mother against decapentaplegic(Smad)2/3 ***,scRNA-seq and a histological analysis of human lung tissue demonstrated a significant upregulation of SERPINE1(the gene encoding PAI-1)and PAI-1 expression in both aging lung tissue and AT2 cells,which was consistent with our findings from animal experiments,providing additional evidence for the pivotal role of PAI-1 during aging and the development of *** research demonstrates that PAI-1,a crucial factor secreted by aging AT2 cells,exerts a pivotal role in promoting the synthesis of Col1a1 in fibroblasts,subsequently leading to Col I deposition,and in driving the progression of PF by mediating the TGF-b/Smad2/3 *** find-ings offer critical evidence for the involvement of epithelial dysfunction in age-related PF and provides potential novel therapeutic targets for clinical interventio

关键词： Aging Pulmonary fibrosis Alveolar type 2 cells PAI-1