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Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： Tao Yang jia-Hao Cai Yan-Zhi Dai Hong-Yu Chen Lei Han li Zhang Wei-Yu liang Xu-Jun li wen-jia li Jing-Yu Wu San-Ping Xie De-Fei Yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant fossils.The Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau.However,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is poor.Here,we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis.These findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene.The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene.This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic conditions.Indeed,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

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Transforming Adolescent Smiles:Correcting Skeletal Mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners

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Current Medical Science 2024年第3期44卷 657-666页

作者： wen-jie FAN jia-qi ZHANG jia-qi ZHAN li HU li-li CHEN Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Stomatology Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Wuhan National High Magnetic Field Center Wuhan430074China The Affiliated lianyungang Hospital of Xuzhou Medical University/The First People’s Hospital of lianyungang Lianyungang222000China The First Affiliated Hospital of Kangda College of Nanjing Medical University/The First People’s Hospital of lianyungang Lianyungang222000China

Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental health.The traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial protrusion.In recent years,an invisible orthodontic technique,without brackets,has become increasingly popular.However,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect outcome.This case report presents an adolescent patient with bimaxillary protrusion and mandibular retrognathia.Based on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular retrognathia.The patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the treatment.This case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction patients.Furthermore,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists.

关键词： mandibular retrusion esthetic orthodontic treatment clear aligners growth potential

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Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation

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Journal of Geriatric Cardiology 2024年第2期21卷 200-210页

作者： Qing YAN jia-Qi liANG Yi-De YUAN Yuan li jia-li FAN wen-Huan WU Pan XU jia-Hong XUE Department of Cardiovascular Medicine the Second Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina Department of Cardiovascular Medicine Zichang People’s HospitalShaanxiChina Department of Ultrasound Xijing HospitalAir Force Military Medical UniversityShaanxiChina

BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an jiaotong University were included in this study.The participants were grouped based on cumulative TyG index values tertiles within 3 months after ablation.Cox regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF recurrence.The predictive value of all risk factors was assessed by receiver operating curve analysis.RESULTS There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values tertiles.After adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,Pline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index values.When considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after RFCA.Monitoring longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence.

关键词： atrial fibrillation index

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Two Indium(III)-based Fluorescent Metal-Organic Frameworks for Highly Sensing Fe^(3+),2,4-DNP,and TNP

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Chemical Research in Chinese Universities 2024年第1期40卷 119-126页

作者： WANG Dan li wen li Guanghua HUA jia liU Yunling State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun130012P.R.China

Two novel metal-organic frameworks(MOFs),JLU-MOF130([In(NH2−BDC)(Imi)(1H−Imi)]·DMF·H2O,NH2−H2BDC=2-aminobenzene-1,4-dicarboxylic acid,1H−Imi=1H-imidazole,DMF=N,N-dimethylformamide)and JLU-MOF131([In(1,4-NDC)(Imi)(1H−Imi)]·DMF0.5,1,4-H_(2)NDC=1,4-naphthalene-dicarboxylic acid),were synthesized.JLU-MOF130 features a three-dimensional(3D)architecture with a neb topology.JLU-MOF131 is characterized by a two-dimensional(2D)structure with an sql topology.JLU-MOF130 has excellent fluorescence detection performance towards Fe^(3+),2,4-dinitrophenol(2,4-DNP),and 2,4,6-trinitrophenol(TNP),but the fluorescence detection performance of JLU-MOF131 is further improved by converting NH2−H2BDC to more conjugated 1,4-H_(2)NDC.The Stern-Volmer(SV)quenching constant(KSV)values of JLU-MOF130 sensing 2,4-DNP,TNP,and Fe^(3+)are 5.24×10^(4),4.44×10^(4),and 4.73×10^(3) L/mol,respectively.The corresponding limit of detection(LOD)values are 1.17,1.36,and 14.59µmol/L.The KSV values for JLU-MOF131 are 1.26×10^(5),9.02×10^(4),and 8.48×103 L/mol,and the corresponding LOD values are 0.35,0.42,and 3.60µmol/L,respectively.interestingly,the emission wavelengths of the two MOFs obviously shift as the fluorescence emission intensities decrease upon the addition of 2,4-DNP and TNP,which can be applied in selective detection.

关键词： Metal-organic framework Fluorescence quenching Fe^(3+) 2 4-Dinitrophenol(2 4-DNP) 2 4 6-Trinitrophenol(TNP)

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Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang wen-Qing Wang jia-Ping lin li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

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Application and progress of artificial intelligence technology in the segmentation of hyperreflective foci in OCT images for ophthalmic disease research

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1138-1143页

作者： jia-Ning Ying Hu li Yan-Yan Zhang wen-Die li Quan-Yong Yi Ningbo Eye Hospital Wenzhou Medical UniversityNingbo 315042Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina

With the advancement of retinal imaging,hyperreflective foci(HRF)on optical coherence tomography(OCT)images have gained significant attention as potential biological biomarkers for retinal neuroinflammation.However,these biomarkers,represented by HRF,present pose challenges in terms of localization,quantification,and require substantial time and resources.In recent years,the progress and utilization of artificial intelligence(AI)have provided powerful tools for the analysis of biological markers.AI technology enables use machine learning(ML),deep learning(DL)and other technologies to precise characterization of changes in biological biomarkers during disease progression and facilitates quantitative assessments.Based on ophthalmic images,AI has significant implications for early screening,diagnostic grading,treatment efficacy evaluation,treatment recommendations,and prognosis development in common ophthalmic diseases.Moreover,it will help reduce the reliance of the healthcare system on human labor,which has the potential to simplify and expedite clinical trials,enhance the reliability and professionalism of disease management,and improve the prediction of adverse events.This article offers a comprehensive review of the application of AI in combination with HRF on OCT images in ophthalmic diseases including age-related macular degeneration(AMD),diabetic macular edema(DME),retinal vein occlusion(RVO)and other retinal diseases and presents prospects for their utilization.

关键词： artificial intelligence deep learning hyperreflective foci image analysis

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Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： jia jia wen Yan Yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable systems.They also emerged in the description of a class special lie conformal algebras called quadratic lie conformal algebras.In this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic lie conformal algebras.Explicitly,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity map.Motivated by the theories of extending structures for lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in E.In particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra lie conformal algebra Extending structures problem Novikovalgebra

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Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang li Qing Yu Feng-feng Chen jia-wen He Hong-mei Yang Meng-nie li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical properties.Previous studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the alloys.In this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%Sc.The results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc addition.The ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

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MicroR-9c-5p and novel-mir50 co-target Akt to regulate Lasioderma serricorne reproduction

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Insect Science 2024年第1期31卷 106-118页

作者： Yi Yan Dong-Dong Qin Hong Yang Kang-Kang Xu Can li wen-jia Yang Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

High fecundity is a common characteristic of insect pests which increases the difficulty of population control.Serine/threonine kinase Akt is an indispensable component of the insulin signaling pathway.Silencing of LsAkt severely hinders reproduction in Lasioderma serricorne,a stored product insect pest.However,the post-transcriptional pathway of LsAkt in L.serricorne remains unknown.This study identified 2 binding sites of miR-9c-5p and novel-mir50 in the coding sequences of LsAkt.The expression profiles of 2 microRNAs(miRNAs)and LsAkt displayed an opposite pattern during the adult stages.Luciferase reporter assay showed that novel-mir50 and miR-9c-5p could downregulate the expression of LsAkt.Overexpression of miR-9c-5p and novel-mir50 by injection of mimics inhibited the expression of LsAkt and reduced oviposition,decreased egg hatchability,and blocked ovarian development.It also decreased the expression of genes involved in ovarian development(LsVg and LsVgR)and the nutritional signaling pathway(LsTOR,LsS6K,and Ls4EBP),and reduced the phosphorylation of Akt.Conversely,injection of miR-9c-5p and novel-mir50 inhibitors induced the expressions of LsAkt,LsVg,LsVgR,LsTOR,LsS6K,and Ls4EBP,enhanced Akt phosphorylation level,and accelerated ovarian development.Injection of bovine insulin downregulated the expression of miR-9c-5p and novel-mir50 and upregulated the LsAkt expression.It also rescued the reproductive development defects associated with miR-9c-5p/novel-mir50 overexpression,forming a positive regulatory loop of insulin signaling.These results indicate that miR-9c-5p/novel-mir50 regulates the female reproduction of L.serricorne by targeting Akt in response to insulin signaling.The data also demonstrate the effects of the insulin/miRNA/Akt regulatory axis in insect reproduction.

关键词： Akt insulin Lasioderma serricorne microRNA reproduction

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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang Guo-Bin jia li-Feng Han wen-Qian liu li Huang Zheng-Han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power system.This model considers the impact of thermal properties of fluid variation on accuracy and has been validated with Simulink.This study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet parameters.Meanwhile,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also analyzed.The results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial values.This simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

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