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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing liu xiang-dong liu Jin-li Li Yue Fang Wen-ting Xie xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh soils.However,the underlying mechanisms remain unclear.This study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat wetlands.The results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and depth.Due to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without crabs.In summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early stages.In winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative fluxes.These results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

Weighted Composition Operators That Preserve Frames on Weighted Hardy Spaces

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1645-1654页

作者： Ya Li dong Rui liu Guo xiang LU School of Mathematical Sciences and LPMC Nankai University School of Statistics and Mathematics Zhongnan University of Economics and Law

In this paper, we characterize weighted composition operators that preserve frames on the weighted Hardy spaces in the unit disk. In particular, we obtain the symbol properties of the bounded invertible weighted composition operators. Moreover, we establish the equivalence between bounded invertible operators and frame-preserving operators. Furthermore, we show that weighted composition operator preserves frames if and only if it preserves the Riesz bases property. Additionally,we investigate the weighted composition operators that preserve tight or normalized tight frames on the Dirichlet space.

关键词： Weighted composition operators Weighted Hardy spaces frames invertible 46B15

Removal of Cr(Ⅵ)by glutaraldehyde-crosslinked chitosan encapsulating microscale zero-valent iron:Synthesis,mechanism,and longevity

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Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu xiang liu Miao Li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)remediation.However,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of mZVI.We prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron particles.The average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this material.Results of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/GCS.The material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight cycles.In this study,we also conducted kinetics and isotherms analysis.Pseudo-second-order model was the most matched kinetics model.The Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous studies.Notably,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day experiment.Therefore,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

Alternative relay regulates the adenosine triphosphatase activity of Locusta migratoria striated muscle myosin

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Insect Science 2024年第2期31卷 435-447页

作者： Jie Hao Chang liu Ning Zhang Jing Li Tong Ni Mingbo Qu xiang-dong Li State Key Laboratory oflntegrated Management of lnsect Pests and Rodents Insttute of ZoologyChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BejingChina School of Bioengeering Dalian University of TechnologyDalianChina

Locust(Locusta migratoria)has a single striated muscle myosin heavy chain(Mhc)gene,which contains 5 clusters of alternative exclusive exons and 1 differently included penultimate exon.The alternative exons of Mhc gene encode 4 distinct regions in the myosin motor domain,that is,the N-terminal SH3-like domain,one lip of the nucleotide-binding pocket,the relay,and the converter.Here,we investigated the role of the alternative regions on the motor function of locust muscle myosin.Using Sf9-baculovirus protein expression system,we expressed and purified 5 isoforms of the locust muscle myosin heavy meromyosin(HMM),including the major isoform in the thorax dorsal longitudinal flight muscle(FL1)and 4 isoforms expressed in the abdominal intersegmental muscle(AB1 to AB4).Among these 5 HMMs,FL1-HMM displayed the highest level of actin-activated adenosine triphosphatase(ATPase)activity(hereafter referred as ATPase activity).To identify the alternative region(s)responsible for the elevated ATPase activity of FL1-HMM,we produced a number of chimeras of FL1-HMM and AB4-HMM.Substitution with the relay of AB4-HMM(encoded by exon-14c)substantially decreased the ATPase activity of FL1-HMM,and conversely,the relay of FL1-HMM(encoded by exon-14a)enhanced the ATPase activity of AB4-HMM.Mutagenesis showed that the exon-14a-encoded residues Gly474 and Asn509 are responsible for the elevated ATPase activity of FL1-HMM.Those results indicate that the alternative relay encoded by exon-14a/c play a key role in regulating the ATPase activity of FL1-HMM and AB4-HMM.

关键词： alternative splicing ATPase Locusta migratoria molecular motor muscle myosin

Haploinsufficiency of Lipin3 leads to hypertriglyceridemia and obesity by disrupting the expression and nucleocytoplasmic localization of Lipin1

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Frontiers of Medicine 2024年第1期18卷 180-191页

作者： Fang Wang Yuxing liu Yi dong Meifang Zhao Hao Huang Jieyuan Jin Liangliang Fan Rong xiang Department of Endocrinology The Third Xiangya Hospital of Central South UniversityChangsha410013China Department of Cellular Biology School of Life SciencesKey Laboratory of Pediatric Rare DiseasesMinistry of EducationCentral South UniversityChangsha410013China

Lipin proteins including Lipin 1–3 act as transcriptional co-activators and phosphatidic acid phosphohydrolase enzymes,which play crucial roles in lipid metabolism.However,little is known about the function of Lipin3 in triglyceride(TG)metabolism.Here,we identified a novel mutation(NM_001301860:p.1835A>T/p.D612V)of Lipin3 in a large family with hypertriglyceridemia(HTG)and obesity through whole-exome sequencing and Sanger sequencing.Functional studies revealed that the novel variant altered the half-life and stability of the Lipin3 protein.Hence,we generated Lipin3 heterozygous knockout(Lipin3-heKO)mice and cultured primary hepatocytes to explore the pathophysiological roles of Lipin3 in TG metabolism.We found that Lipin3-heKO mice exhibited obvious obesity,HTG,and non-alcoholic fatty liver disorder.Mechanistic study demonstrated that the haploinsufficiency of Lipin3 in primary hepatocytes may induce the overexpression and abnormal distribution of Lipin1 in cytosol and nucleoplasm.The increased expression of Lipin1 in cytosol may contribute to TG anabolism,and the decreased Lipin1 in nucleoplasm can reduce PGC1α,further leading to mitochondrial dysfunction and reduced TG catabolism.Our study suggested that Lipin3 was a novel disease-causing gene inducing obesity and HTG.We also established a relationship between Lipin3 and mitochondrial dysfunction.

关键词： Lipin3 Lipin1 hypertriglyceridemia obesity mitochondrial dysfunction

Flower development and sexual dimorphism in Vernicia montana

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Horticultural Plant Journal 2024年第2期10卷 586-600页

作者： Wenying Li Jingzhen Chen xiang dong Meilan liu Guibin Wang Lin Zhang Key Laboratory of Cultivation and Protection for Non-wood Forest Trees Ministry of EducationCentral South University of Forestry and TechnologyChangshaHunan 410004China State Key Laboratory of Utilization of Woody Oil Resource Hunan Academy of ForestryChangshaHunan 410004China College of Forestry Nanjing Forestry UniversityNanjingJiangsu 210037China

The mu oil tree(Vernicia montana Lour.) is a dioecious species, but the genetic mechanisms underlying its phenotypic sexual dimorphism are unclear. In this study, we determined two pivotal phases of sex differentiation of mu oil tree via morphological and histological analyses of unisexual flowers:(Ⅰ) differentiation of male or female primordia to produce staminate flowers(SFs) or transient hermaphrodite flowers(HFs),and(Ⅱ) complete abortion of stamens in transient HFs to generate pistillate flowers(PFs). A total of 1621 sex-biased genes were identified by comparative transcriptome analysis which exhibited elevated rates of protein evolution than unbiased genes. The female-biased genes were enriched in the production of defense compounds while male-biased genes were focused on the production of viable pollens. Transcriptomebased analysis revealed that the differentially expressed genes(DEGs) between PFs and SFs in phase Ⅰ involved in abscisic acid(ABA), auxin(AUX), cytokinin(CK), ethylene(ET), and gibberellin(GA) biosynthesis and signaling showed higher expression levels in males than in females in general, whereas the DEGs involved in jasmonic acid(JA) and salicylic acid(SA) pathways displayed opposite expression patterns. Moreover,differentially expressed endogenous ABA, AUX, GAs, JA, and SA exhibited consistent biased expression patterns with the DEGs by UPLC-MSbased analysis. Exogenous application of an anti-ethylene plant growth regulator could promote the development of stamens in PFs and generated HFs. Comparative transcriptomic and hormonal analyses of PFs and SFs in phase Ⅱ indicated an increase in ET concentration when abortion of stamens in PFs occurred. This study suggested that phytohormones play key roles in sex dimorphism and ET may determine the development of stamens in PFs of mu oil tree, which provides an insight into plant sex differentiation mechanisms.

关键词： Mu oil tree Flower development Sexual dimorphism Sex bias Ethylene

Giant bile duct dilatation in newborn:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1150-1156页

作者： dong-Wen Quan Peng-Gang Li xiang-Hua Xu Shi-Qi liu The Second Clinical Medical School Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina The First School of Clinical Medicine Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Neonatal Surgery Xi’an Children’s Hospital Affiliated Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina

BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical practice.Infants born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ dysfunction.The treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control bleeding.CASE SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant CBD.The patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 d.The abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of pregnancy.This finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary dilatation.No specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 cm.Based on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant CBD.Laparoscopic surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemostasis,as well as severe biliary system infection

关键词： Acute cholangitis Congenital biliary dilation Laparoscopic surgery vs Open hepatic duct-jejunostomy Case report

Achieving Ultra-Broad Microwave Absorption Bandwidth Around Millimeter-Wave Atmospheric Window Through an Intentional Manipulation on Multi-Magnetic Resonance Behavior

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Nano-Micro Letters 2024年第9期16卷 291-307页

作者： Chuyang liu Lu Xu Xueyu xiang Yujing Zhang Li Zhou Bo Ouyang Fan Wu dong‑Hyun Kim Guangbin Ji School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuPeople’s Republic of China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China School of Physics Chungbuk National UniversityCheongju 28644South Korea Department of Chemistry School of ScienceTianjin UniversityTianjin 300072People’s Republic of China

The utilization of electromagnetic waves is rapidly advancing into the millimeter-wave frequency range,posing increasingly severe challenges in terms of electromagnetic pollution prevention and radar stealth.However,existing millimeter-wave absorbers are still inadequate in addressing these issues due to their monotonous magnetic resonance pattern.In this work,rare-earth La^(3+)and non-magnetic Zr^(4+)ions are simultaneously incorporated into M-type barium ferrite(BaM)to intentionally manipulate the multi-magnetic resonance behavior.By leveraging the contrary impact of La^(3+)and Zr^(4+)ions on magnetocrystalline anisotropy field,the restrictive relationship between intensity and frequency of the multi-magnetic resonance is successfully eliminated.The magnetic resonance peak-differentiating and imitating results confirm that significant multi-magnetic resonance phenomenon emerges around 35 GHz due to the reinforced exchange coupling effect between Fe^(3+)and Fe^(2+)ions.Additionally,Mosbauer spectra analysis,first-principle calculations,and least square fitting collectively identify that additional La^(3+)doping leads to a profound rearrangement of Zr^(4+)occupation and thus makes the portion of polarization/conduction loss increase gradually.As a consequence,the La^(3+)-Zr^(4+)co-doped BaM achieves an ultra-broad bandwidth of 12.5+GHz covering from 27.5 to 40+GHz,which holds remarkable potential for millimeter-wave absorbers around the atmospheric window of 35 GHz.

关键词： Microwave absorption Ultra-broad bandwidth M-type barium ferrite Magnetocrystalline anisotropy field Multimagnetic resonance

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast loading.First,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage test.Second,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation method.Finally,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact block.The calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the model.The residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged panel.The results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy

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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning liu Wei Zhang Peng-yue Wang Yi-xian liu xiang-yi Jiao Ao-xiang Wan Cheng-gang Wang Guo-dong Tong Shou-mei Xiong School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China FAW Group Co. Ltd.Changchun 130013China China FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg alloy.The AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg alloy.Refining elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-Al.At a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and net-shrinkage.With an increase in slow shot speed,the size and number of ESCs and porosities significantly reduce.In addition,the distribution of ESCs is more dispersed and the net-shrinkage disappears.The tensile property is greatly improved by adopting a higher slow shot speed.The ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property