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A Phase-field Model to Simulate Recrystallization in an AZ31 Mg Alloy in Comparison of Experimental Data

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Journal of Materials Science & Technology 2008年第6期24卷 829-834页

作者： Mingtao wang b.y.Zong Gang wang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

A model has been established to simulate the realistic spatio-temporal microstructure evolution in recrystallization of a magnesium alloy using the phase field approach. A set of rules have been proposed to decide the real physical value of all parameters in the model. The thermodynamic software THERMOCALC is applied to determine the local chemical free energy and strain energy, which is added to the free energy density of grains before recrystallization. The Arrhenius formula is used to describe boundary mobility and the activity energy is suggested with a value of zinc segregation energy at the boundary. However, the mobility constant in the formula was found out by fitting to a group of grain size measurements during recrystallization of the alloy. The boundary range is suggested to decide the gradient parameters in addition of fitting to the experimental boundary energy value. These parameter values can be regarded as a database for other similar simulations and the fitting rules can also be applied to build up databases for any other alloy systems. The simulated results show a good agreement with reported experimental measurement of the alloy at the temperatures from 300 to 400℃ for up to 100 min but not at 250℃. This implies a mechanism variation in activity energy of the boundary mobility in the alloy at low temperature.

关键词： Static recrystallization Phase field model Magnesium alloys Microstructure

Frequent recombination in Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae)ribosomal 18S rDNA

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Acta Oceanologica Sinica 2024年第8期43卷 98-103页

作者： Li Gong Tingqi Jiang bilin Hu Kaixin wang Nannan Zhang Zengliang Miao National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization Zhejiang Ocean UniversityZhoushan 316022China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China

The conventional theory of concerted evolution has been used to explain the lack of sequence variation in ribosomal RNA(rRNA)genes across diverse eukaryotic ***,recent investigations into rRNA genes in flatfish genome have resulted in controversial *** study focuses on 18S rRNA genes of the widely distributed tongue sole,Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae),aiming to explore sequence *** distinct 18S rDNA sequence types(Type A,b,R1,R2,and R3)were identified,suggesting a departure from concerted evolution.A combination of general criteria and variations in highly conserved regions were employed to detect *** results pinpointed Type A sequences as potential pseudogenes due to significant sequence variations and deviations in secondary structure within highly conserved *** types(Type R1,R2,and R3)were identified as recombinants between Type A and b sequences,with simple crossing over and gene conversion as the most likely recombination *** findings not only contribute to rRNA pseudogene identification but also shed light on the evolutionary dynamics of rRNA genes in teleost genomes.

关键词： ribosomal RNA tongue sole non-concerted evolution pseudogene crossing over gene conversion

On implications of somatostatin in diabetic retinopathy

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Neural Regeneration Research 2024年第9期19卷 1984-1990页

作者： yanhong Fang Qionghua wang youjian Li Li Zeng Jian Liu Kepeng Ou Department of Ophthalmology Chongqing University Jiangjin HospitalChongqingChina College of Pharmacy National&Local Joint Engineering Research Center of Targeted and Innovative TherapeuticsIATTIChongqing University of Arts and SciencesChongqingChina Shandong Provincial Hospital Shandong Laboratory Animal CenterScience and Technology Innovation CenterShandong First Medical University&Shandong Academy of Medical SciencesJinanShandong ProvinceChina Academic Unit of Ophthalmology Bristol Medical SchoolUniversity of BristolBristolUK

Somatostatin,a naturally produced neuroprotective peptide,depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the *** this review,we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar *** neuroprotection,which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy,triggers retinal neurovascular unit impairment and microvascular *** replacement is a promising treatment for retinal neurodegeneration in diabetic *** pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been *** one such trial(EUROCONDOR),topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction,but had no impact on the onset of diabetic ***,we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage *** order to achieve early prevention of diabetic retinopathy initiation,and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy,several issues need to be *** include the needs to:a)update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration,b)identify patient subgroups who would benefit from somatostatin analog supplementation,c)elucidate the interactions of somatostatin,particularly exogenously-delivered somatostatin analogs,with other retinal peptides in the context of hyperglycemia,and d)design safe,feasible,low cost,and effective administration routes.

关键词： diabetes retinopathy excitotoxicity growth hormone insulin like growth factor irisin neurodegeneration neuroinflammation neuroprotection neurovascular unit octreotide oxidative stress somatostatin

Structural Origins for Enhanced Thermal Stability and Glass‑Forming Ability of Co–b Metallic Glasses with y and Nb Addition

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 962-972页

作者： Shuang Ma Junyu Zhang Xudong wang Rie y.Umetsu Li Jiang Wei Zhang Man yao Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Institute for Materials Research Tohoku UniversitySendai 980‑8577Japan

The effects of y and Nb addition on thermal stability,glass-forming ability(GFA),and magnetic softness of Co75b25 metallic glass(MG)were comprehensively *** experimental results indicated that the thermal stability,GFA,and magnetic softness of the studied MGs increase in the order Co_(75)b_(25)3)Nb_(2)b_(25)y_(3.5)b_(25)y_(3.5)Nb_(2)b_(25).The structural origins of the improved properties were revealed by ab initio molecular dynamics(AIMD)simulations and density functional theory(DFT)*** showed that the b-centered prism units are the primary structure-forming units of the four MGs,connect through vertex-,edge-,and face-shared(VS,ES,and FS)atoms,and Co-centered units tend to connect with Co/b-centered units via the intercross-shared(IS)*** addition of y and Nb not only plays the role of connecting atoms but also enhances both bond strengths and the fractions of icosahedral-like units in increasing order Co_(75)b_(25)3)Nb_(2)b_(25)y_(3.5)b_(25)y_(3.5)Nb_(2)b_(25),which is conducive to the enhancement of the structural stability,atomic packing density,and viscosity,thereby improving thermal stability and *** addition,the improvement of structural stability and homogeneity leads to enhanced magnetic softness.

关键词： Co-based metallic glasses Thermal stability Glass-forming ability Soft magnetic property Ab initio molecular dynamics simulations Local atomic structure

Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.S.yuan X.y.Gao Z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

An update on hormonal regulation of early embryo-fallopian tube interactions: insights for improvements of assisted reproductive technology outcomes

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Reproductive and Developmental Medicine 2024年第1期8卷 39-49页

作者： Suranga P.Kodithuwakku Ernest H.y.Ng William S.b.yeung Kai-Fai Lee Department of Obstetrics and Gynaecology LKS Faculty of MedicineThe University of Hong KongHong Kong SAR 999077China Department of Animal Science Faculty of AgricultureUniversity of PeradeniyaPeradeniya 20400Sri Lanka Shenzhen Key Laboratory of Fertility Regulation.The University of Hong Kong-Shenzhen Hospital Shenzhen 518053China

Human fallopian tubes(FTs)play important roles in the whole reproductive *** are the site for the final maturation of gametes,fertilization,transport of preimplantation embryos,and early embryonic development before entering the *** these functions are critical in the establishment of a successful *** the embryo is in transit through the FT,the FT microenvironment changes through endocrine,paracrine,autocrine,and juxtacrine mechanisms which involve various hormones and bioactive substances mainly from the neighboring ***,the interactions between the embryo and the FT may be the earliest embryo-maternal communications that are essential for the establishment of *** review critically discusses the evidence of various hormonal and bioactive mediated control of the microenvironment in the FTs during the earliest embryo-maternal ***,we highlight existing gaps in the knowledge and the importance of exploring more of the physiology of FTs which will hold the key to producing high-quality embryos for patients seekingin vitro fertilization(IVF)treatments.

关键词： Fallopian tube Embryo Maternal-embryo communication Hormonal control

Early-life famine exposure,adulthood obesity patterns,and risk of low-energy fracture

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Frontiers of Medicine 2024年第1期18卷 192-203页

作者： Hongyan Qi Chunyan Hu Jie Zhang Lin Lin Shuangyuan wang Hong Lin Xiaojing Jia yuanyue Zhu yi Zhang Xueyan Wu Mian Li Min Xu yu Xu Tiange wang Zhiyun Zhao Weiqing wang yufang bi Meng Dai yuhong Chen Jieli Lu Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai National Clinical Research Center for Endocrine and Metabolic Diseases Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the People’s Republic of ChinaShanghai National Center for Translational MedicineRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China

Malnutrition in early life increases the risk of osteoporosis,but the association of early-life undernutrition combined with adulthood obesity patterns with low-energy fracture remains *** study included 5323 community-dwelling subjects aged⩾40 years from ***-life famine exposure was identified based on the participants’birth *** obesity was assessed using the body mass index(bMI),and abdominal obesity was evaluated with the waist-to-hip ratio(WHR).Low-energy fracture was defined as fracture occurring after the age of⩾40 typically caused by falls from standing height or *** to the nonexposed group,the group with fetal,childhood,and adolescence famine exposure was associated with an increased risk of fracture in women with odds ratios(ORs)and 95%confidence intervals(CIs)of 3.55(1.57–8.05),3.90(1.57–9.71),and 3.53(1.05–11.88),respectively,but not in *** interactions were observed between fetal famine exposure and general obesity with fracture among women(P for interaction=0.0008).Furthermore,compared with the groups with normal bMI and WHR,the group of women who underwent fetal famine exposure and had both general and abdominal obesity had the highest risk of fracture(OR,95%CI:3.32,1.17–9.40).These results indicate that early-life famine exposure interacts with adulthood general obesity and significantly increases the risk of low-energy fracture later in life in women.

关键词： famine obesity body mass index waist-to-hip ratio low-energy fracture

Loss of SHROOM3 affects neuroepithelial cell shape through regulating cytoskeleton proteins in cynomolgus monkey organoids

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Zoological Research 2024年第2期45卷 233-241页

作者： Peng Li Ting Zhang Ruo Wu Jun-yu Zhang yan Zhuo Shan-Gang Li Jiao-Jian wang Wen-Ting Guo Zheng-bo wang yong-Chang Chen State Key Laboratory of Primate biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunmingYunnan 650500China yunnan Key Laboratory of Primate biomedical Research KunmingYunnan 650500China

Neural tube defects(NTDs)are severe congenital neurodevelopmental disorders arising from incomplete neural tube *** folate supplementation has been shown to mitigate the incidence of NTDs,some cases,often attributable to genetic factors,remain *** SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation;at present,however,the underlying mechanism remains *** tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural *** determine the role of SHROOM3 in early developmental morphogenesis,we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate *** of SHROOM3 resulted in shorter neuroepithelial cells and smaller *** morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins,namely fibrous actin(F-actin),myosin II,and phospho-myosin light chain(PMLC),to the apical side of the neuroepithelial ***,these defects were not rescued by folate *** sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ *** summary,we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.

关键词： Neural tube defects SHROOM3 Neuroepithelial Organoids Cynomolgus monkey

Sentiment Analysis Using E-Commerce Review Keyword-Generated Image with a Hybrid Machine Learning-based Model

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Computers, Materials & Continua 2024年第7期80卷 1581-1599页

作者： Jiawen Li yuesheng Huang yayi Lu Leijun wang yongqi Ren Rongjun Chen School of Computer Science Guangdong Polytechnic Normal UniversityGuangzhou510665China Hubei Province Key Laboratory of Occupational Hazard Identification and Control Wuhan University of Science and TechnologyWuhan430065China

In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and *** understand their emotional expressions in facing different shopping experience scenarios,this paper presents a sentiment analysis method that combines the ecommerce reviewkeyword-generated imagewith a hybrid machine learning-basedmodel,inwhich theWord2Vec-TextRank is used to extract keywords that act as the inputs for generating the related images by generative Artificial Intelligence(AI).Subsequently,a hybrid Convolutional Neural Network and Support Vector Machine(CNNSVM)model is applied for sentiment classification of those keyword-generated *** method validation,the data randomly comprised of 5000 reviews from Amazon have been *** superior keyword extraction capability,the proposedmethod achieves impressive results on sentiment classification with a remarkable accuracy of up to 97.13%.Such performance demonstrates its advantages by using the text-to-image approach,providing a unique perspective for sentiment analysis in the e-commerce review data compared to the existing ***,the proposed method enhances the reliability and insights of customer feedback surveys,which would also establish a novel direction in similar cases,such as social media monitoring and market trend research.

关键词： Sentiment analysis keyword-generated image machine learning Word2Vec-TextRank CNN-SVM