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Lagrangian coherent structure analysis on transport of Acetes chinensis along coast of Lianyungang,China

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Journal of Oceanology and Limnology 2024年第1期42卷 345-359页

作者： Kexin WANG Xueqing ZHANG Qi lou Xusheng xiang Ying XIONG College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Marine Environment and Ecology Ministry of Education of ChinaOcean University of ChinaQingdao 266100China Jiangsu Marine Fisheries Research Institute Nantong 226007China

Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the Acetes chinensis in the Lianyungang nearshore licensed fishing area.The Lagrangian frame approaches including the Lagrangian coherent structures theory,Lagrangian residual current,and Lagrangian particle-tracking model were applied to find the transport pathways and aggregation characteristics of Acetes chinensis.There exist some material transport pathways for Acetes chinensis passing through the licensed fishing area,and Acetes chinensis is easy to accumulate in the licensed fishing area.The main mechanism forming this distribution pattern is the local circulation induced by the nonlinear interaction of topography and tidal flow.Both the Lagrangian coherent structure analysis and the particle trajectory tracking indicate that Acetes chinensis in the licensed fishing area come from the nearshore estuary.This work contributed to the adjustment of licensed fishing area and the efficient utilization of fishery resources.

关键词： plankton accumulation hydrodynamic model Lagrangian particle-tracking model Lagrangian analysis

Reynolds-number scaling analysis on lift generation of a flapping and passive rotating wing with an inhomogeneous mass distribution

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Chinese Journal of Aeronautics 2024年第2期37卷 259-269页

作者： Suyang QIN Haotian HANG Yang xiang hong LIU J.C.Wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai 200240china

Insects usually fly by passively rotating wings,which has been applied to the design of flapping-wing Micro-Air Vehicles(MAVs)to reduce mechanical complexity.In this paper,a robotic passive rotating-wing model is designed to investigate wing kinematics and lift generation,which are measured by a high-speed camera and a force transducer,respectively.In addition,flow fields are measured using the Particle Image Velocimetry(PIV).Experimental results demonstrate that passive rotating motion has a coordinative relationship with actively stroking motion.As the stroke amplitude or frequency increases,the rotating amplitude is enlarged.To characterize the active stroking motion,a driving Reynolds number Redrivingis defined,which varies from 68 to 366 in this study.Moving the gravity center of the wing towards trailing ed ge induces the increase of additional torque M,which decreases the wing rotating amplitude and promotes the advance of wing rotation.We find that the timing of wing rotation is gradually delayed and the mean lift coefficient C^(-)_(L)monotonously decreases as Redrivingincreases.By increasing the additional torque M,C^(-)_(L)is slightly improved and approaches to the lift coefficient of a real fruit fly at driving Re approximately equal to 230.The instantaneous lifts combined with the vortical structures further demonstrate that the lift generation associated with wing rotation is mainly attributed to the growth of the LeadingEdge Vortex(LEV)and the passive wake capture mechanism.Passive wake capture is influenced by LEV,reversal stroke motion and wing additional torque together,which can only maintain the lift at a high level for a considerable period.The high-lift generation mechanisms of flapping and passive rotating flight could shed light on the simplified design of MAVs and the improvement of their aerodynamic performance.

关键词： Flapping flight Unsteady lift Passive rotation Vortex flow Leading-edge vortex

Bioinspired nanotransducers for neuromodulation

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Nano Research 2024年第2期17卷 618-632页

作者： Fan Yang xiang Wu Sa Cai Guosong hong Department of Materials Science and Engineering Stanford UniversityStanfordCA 94305USA Wu Tsai Neurosciences Institute Stanford UniversityStanfordCA 94305USA School of Science Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China

The field of neuromodulation has experienced significant advancements in the past decade,owing to breakthroughs in disciplines such as materials science,genetics,bioengineering,photonics,and beyond.The convergence of these fields has resulted in the development of nanotransducers,devices that harness the synergies of these diverse disciplines.These nanotransducers,essential for neuromodulation,often draw inspiration from energy conversion processes found in nature for their unique modalities.In this review,we will delve into the latest advancements in wireless neuromodulation facilitated by optical,magnetic,and mechanical nanotransducers.We will examine their working principles,properties,advantages,and limitations in comparison to current methods for deep brain neuromodulation,highlighting the impact of natural systems on their design and functionality.Additionally,we will underscore potential future directions,emphasizing how continued progress in materials science,neuroscience,and bioengineering might expand the horizons of what is achievable with nanotransducer-enabled neuromodulation.

关键词： bioinspired synthesis neuromodulation mechanoluminescence focused ultrasound nanotransducers sono-optogenetics

Angiosperm-wide analysis of fruit and ovary evolution aided by a new nuclear phylogeny supports association of the same ovary type with both dry and fleshy fruits

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Journal of Integrative Plant Biology 2024年第2期66卷 228-251页

作者： Yezi xiang Taikui Zhang Yiyong Zhao hongjin Dong hongyi Chen Yi Hu Chien-Hsun Huang Jun xiang hong Ma State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity and Ecological EngineeringInstitute of Plant BiologyCenter of Evolutionary BiologySchool of Life SciencesFudan UniversityShanghai 200438China Department of Biology Howard Hughes Medical InstituteDuke UniversityDurhamNC 27708USA Department of Biology the Eberly College of Scienceand the Huck Institutes of the Life Sciencesthe Pennsylvania State UniversityUniversity ParkPA 16802USA Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization College of Biology and Agricultural ResourcesHuanggang Normal UniversityHuanggang 438000China

Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and families.Thus we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain placements.Using this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial Revolution.The robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and magnoliids.Moreover,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple families.One of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and drupes.This new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversification.

关键词： angiosperm fruit evolution MADS-box molecular clock nuclear phylogeny ovary and fruit developmental genes

Factors and Their Impact on Treatment Effect of Acupuncture in Different Outcomes:A Meta-Regression of Acupuncture Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2024年第3期30卷 260-266页

作者： XIU Wen-cui GANG Wei-juan ZHOU Qi SHI Lan-jun HU xiang-yu MING Tian-yu LUO Zhen ZHANG Yu-qing JING xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China China Center for Evidence-Based Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijing100700China Department of Health Research Methods Evidenceand ImpactMcMaster UniversityHamiltonOntarioL8S 4L8Canada Center for Evidence-Based Integrative Medicine-Clarity Collaboration Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China

Background:The effects of acupuncture have varied in different randomized controlled trials(RCTs),and there are many factors that influence treatment effect of acupuncture in different outcomes,with conflicting results.Objective:To identify factors and their impact on the treatment effect of acupuncture in different outcomes.Methods:Acupuncture RCTs were searched from 7 databases including Medline(Pub Med),Embase,Cochrane Central Register of Controlled Trials,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biology Medicine disc between January 1st,2015 and December 31st,2019.Eligible studies must compare acupuncture to no acupuncture,sham acupuncture,or waiting lists,and report at least 1patient-important outcome.A multi-level meta-regression was conducted using a 3-level robust mixed model and univariate analyses were performed for all independent variables,even those excluded from the multivariable model due to collinearities.We used thresholds of 0.2 and 0.4 for the difference of standardized mean differences(SMDs),categorising them as small(0.4) effects.Results:The pain construct analysis involved 211 effect estimates from 153 studies and 14 independent variables.High-frequency acupuncture treatment sessions produced larger effects compared to low-frequency sessions [large magnitude,the difference of adjusted SMDs 0.46,95% confidence interval(CI) 0.07 to 0.84;P=0.02].The non-pain symptoms construct analysis comprised 323 effect estimates from 231 studies and 15 independent variables.Penetrating acupuncture showed moderately larger effects when compared to non-penetrating acupuncture(0.30,95% CI 0.06 to 0.53;P=0.01).The function construct analysis included 495 effect estimates from 274 studies and 14 independent variables.Penetrating acupuncture and the flexible acupuncture regimen showed moderately larger effects,compared to non-penetrating acupuncture and fixed regimen,respectively(0.40,95% CI 0 to 0.80;P=0.05;0.29,95% CI 0.06 to 0.53;P=0.01).

关键词： acupuncture randomized controlled trial patient-important outcome meta-regression

Effect of different bottom blowing elements on stirring characteristics of molten bath in converter

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Journal of Iron and Steel Research(International) 2024年第2期31卷 368-376页

作者： Ming Lv Shuang-ping Chen hong-min Guo Yi-jie Hao xiang-dong Xing School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina Shaanxi Longmen Steel Company Hancheng715405ShaanxiChina

The bottom blowing element is the key equipment to ensure the bottom blowing effect of the converter.Three types of bottom blowing elements,dispersive type(D1),double circular seam(D2)and straight cylinder type(D3),were built,and the effects of bottom blowing element type on molten bath flow,wall erosion and furnace bottom erosion were simulated.It was found that when the bottom blowing elements of dispersive type(D1)and double circular seam(D2)were used,the dead zone area in the lower part of the molten bath was smaller,and the high-speed zone area was larger;therefore,the stirring effect on the bottom melt was better.When the straight cylinder type(D3)bottom blowing element was used,the gas penetrated the molten bath at a faster rate to reach the surface of molten bath and failed to disperse in the bottom molten bath,and the wall shear stress near the nozzle outlet was larger.When argon was blown by three different bottom blowing elements,the area of the wall shear stress greater than 3 Pa was 4.8,5.6 and 8.7 cm2,respectively,within 0.2 m of the bottom blowing nozzle outlet.

关键词： Converter steelmaking Bottom blowing element Molten bath stirring Wall erosion

Calcitonin gene-related peptide inhibits neuronal apoptosis in heatstroke rats via PKA/p-CREB pathway

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Chinese Journal of Traumatology 2024年第1期27卷 18-26页

作者： Jie Zhu Ya-hong Chen Jing-Jing Ji Cheng-xiang Lu Zhi-Feng Liu Department of Pediatric General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Medical Intensive Care Unit General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Intensive Care Unit Zhongshan Hospital Xiamen UniversityXiamenFujian province361004China

Purpose:The incidence of heatstroke(HS)is not particularly high;however,once it occurs,the consequences are serious.It is reported that calcitonin gene-related peptide(CGRP)is protective against brain injury in HS rats,but detailed molecular mechanisms need to be further investigated.In this study,we further explored whether CGRP inhibited neuronal apoptosis in HS rats via protein kinase A(PKA)/p-cAMP response element-binding protein(p-CREB)pathway.Methods:We established a HS rat model in a pre-warmed artificial climate chamber with a temperature of(35.5±0.5)℃and a relative humidity of 60%±5%.Heatstress was stopped once core body temperature reaches above 41℃.A total of 25 rats were randomly divided into 5 groups with 5 animals each:control group,HS group,HS+CGRP group,HS+CGRP antagonist(CGRP8-37)group,and HS+CGRP+PKA/p-CREB pathway blocker(H89)group.A bolus injection of CGRP was administered to each rat in HS+CGRP group,CGRP8-37(antagonist of CGRP)in HS+CGRP8-37 group,and CGRP with H89 in HS+CGRP+H89 group.Electroencephalograms were recorded and the serum concentration of S100B,neuron-specific enolase(NSE),neuron apoptosis,activated caspase-3 and CGRP expression,as well as pathological morphology of brain tissue were detected at 2 h,6 h,and 24 h after HSin vivo.The expression of PKA,p-CREB,and Bcl-2 in rat neurons were also detected at 2 h after HSin vitro.Exogenous CGRP,CGRP8-37,or H89 were used to determine whether CGRP plays a protective role in brain injury via PKA/p-CREB pathway.The unpairedt-test was used between the 2 samples,and the mean±SD was used for multiple samples.Double-tailedp<0.05 was considered statistically significant.Results:Electroencephalogram showed significant alteration ofθ(54.50±11.51vs.31.30±8.71,F=6.790,p=0.005)andαwave(16.60±3.21vs.35.40±11.28,F=4.549,p=0.020)in HS group compared to the control group 2 h after HS.The results of triphosphate gap terminal labeling(TUNEL)showed that the neuronal apoptosis of HS rats was increased in the cortex(9.67±3.16vs.1.80±1.10,F=11.002,p=0.001)and

关键词： Heatstroke Calcitonin gene-related peptide Brain injury Apoptosis

NbB_(2)Modified Al-Cu Alloys Fabricated by Freeze-Ablation Casting under High Cooling Rate Solidification

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 921-938页

作者： xiang Kong Yu Wang hong Xu Haotian Fan Yuewu Zheng Beibei Xie School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

At present,improving the properties of aluminum alloys is generally achieved by increasing the cooling rate of the melt and adding micro-nano particles.Controlling the cooling rate of the melt to improve the refining effect of grain refiner is still a difficult problem in the aluminum alloy casting industry.An innovative and environmentally friendly casting process,known as freeze ablation,was introduced during the preparation of an Al–NbB_(2) intermediate alloy.This process significantly enhanced the cooling rate of the melt.The results indicated that the Al–NbB_(2) intermediate alloy produced under high cooling rates had a noticeable refining effect on Al–Cu alloys,with smaller NbB2 particles demonstrating superior refining performance.The average grain size of the refined Al–Cu alloy decreased from 154 to 69μm,the tensile strength increased by 12%,the fluidity increased by 18.4%,and the hot tearing index decreased from 144 to 12.The matching degree between NbB_(2) andα-Al was calculated using high-resolution transmission electron microscopy and the edge-to-edge model.It was found that the atomic interplanar spacing and the interatomic spacing mismatch between NbB_(2)’splane and Al were both less than 10%,which further proved that NbB2 could serve as an effective nucleation site forα-Al grains to achieve grain refinement.

关键词： Grain refinement Freeze ablation Particle size control Mechanical properties Process properties

Recent progress in hair follicle stem cell markers and their regulatory roles

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World Journal of Stem Cells 2024年第2期16卷 126-136页

作者： Yi-Zhan Xing Hai-Ying Guo Fei xiang Yu-hong Li Department of Cell Biology Army Medical UniversityChongqing 400038China Institute of Burn Research Southwest HospitalArmy Medical UniversityChongqing 400038China

Hair follicle stem cells(HFSCs)in the bulge are a multipotent adult stem cell population.They can periodically give rise to new HFs and even regenerate the epidermis and sebaceous glands during wound healing.An increasing number of biomarkers have been used to isolate,label,and trace HFSCs in recent years.Considering more detailed data from single-cell transcriptomics technology,we mainly focus on the important HFSC molecular markers and their regulatory roles in this review.

关键词： Hair follicle stem cells Bulge Secondary hair germ Marker Single-cell RNA-sequencing