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Simulation of spatially coupling dynamic response of train-track time-variant system 被引量:26
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作者 向俊 李德建 曾庆元 《Journal of Central South University of Technology》 2003年第3期226-230,共5页
There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of tra... There exist three problems in the calculation of lateral vibration of the train-track time-variant system athome and abroad and the method to solve them is presented. Spatially coupling vibration analysis model of train-track time-variant system is put forward. Each vehicle is modeled as a multi-body system with 26 degrees of freedomand the action of coupler is also considered. The track structure is modeled as an assembly of track elements with 30degrees of freedom, then the spatially coupling vibration matrix equation of the train-track time-variant system is es-tablished on the basis of the principle of total potential energy with stationary value and the "set-in-right-position"rule. The track vertical geometric irregularity is considered as the excitation source of the vertical vibration of thesystem, and the hunting wave of car bogie frame is taken as the excitation source of lateral vibration of the system.The spatially coupling vibration matrix equation of the system is solved by Wilson-θ direct integration method. Theapproximation of the calculated results to the spot test results demonstrates the feasibility and effectiveness of thepresented analysis method. Finally, some other vibration responses of the system are also obtained. 展开更多
关键词 vibration TRAIN TRACK time-variant system HUNTING wave car BOGIE FRAME excitation source
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The Variants of the MGSS Methods for Complex Symmetric Linear System of Equations
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作者 Changfeng Ma Xiaojuan Yu 《Communications in Mathematical Research》 2025年第2期173-188,共16页
Recently,inspired by a modified generalized shift-splitting iteration method for complex symmetric linear systems,we propose two variants of the modified generalized shift-splitting iteration(MGSS)methods for solving ... Recently,inspired by a modified generalized shift-splitting iteration method for complex symmetric linear systems,we propose two variants of the modified generalized shift-splitting iteration(MGSS)methods for solving com-plex symmetric linear systems.One is a parameterized MGSS iteration method and the other is a modified parameterized MGSS iteration method.We prove that the proposed methods are convergent under appropriate constraints on the parameters.In addition,we also give the eigenvalue distributions of differ-ent preconditioned matrices to verify the effectiveness of the preconditioners proposed in this paper. 展开更多
关键词 Complex symmetric linear system variants of MGSS method convergence analysis
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Pigeon-Inspired Optimization Algorithm:Definition,Variants,and Its Applications in Unmanned Aerial Vehicles
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作者 Yu-Xuan Zhou Kai-Qing Zhou +2 位作者 Wei-Lin Chen Zhou-Hua Liao Di-Wen Kang 《Computers, Materials & Continua》 2026年第4期186-225,共40页
ThePigeon-InspiredOptimization(PIO)algorithmconstitutes ametaheuristic method derived fromthe homing behaviour of pigeons.Initially formulated for three-dimensional path planning in unmanned aerial vehicles(UAVs),the ... ThePigeon-InspiredOptimization(PIO)algorithmconstitutes ametaheuristic method derived fromthe homing behaviour of pigeons.Initially formulated for three-dimensional path planning in unmanned aerial vehicles(UAVs),the algorithmhas attracted considerable academic and industrial interest owing to its effective balance between exploration and exploitation,coupled with advantages in real-time performance and robustness.Nevertheless,as applications have diversified,limitations in convergence precision and a tendency toward premature convergence have become increasingly evident,highlighting a need for improvement.This reviewsystematically outlines the developmental trajectory of the PIO algorithm,with a particular focus on its core applications in UAV navigation,multi-objective formulations,and a spectrum of variantmodels that have emerged in recent years.It offers a structured analysis of the foundational principles underlying the PIO.It conducts a comparative assessment of various performance-enhanced versions,including hybrid models that integrate mechanisms from other optimization paradigms.Additionally,the strengths andweaknesses of distinct PIOvariants are critically examined frommultiple perspectives,including intrinsic algorithmic characteristics,suitability for specific application scenarios,objective function design,and the rigor of the statistical evaluation methodologies employed in empirical studies.Finally,this paper identifies principal challenges within current PIO research and proposes several prospective research directions.Future work should focus on mitigating premature convergence by refining the two-phase search structure and adjusting the exponential decrease of individual numbers during the landmark operator.Enhancing parameter adaptation strategies,potentially using reinforcement learning for dynamic tuning,and advancing theoretical analyses on convergence and complexity are also critical.Further applications should be explored in constrained path planning,Neural Architecture Search(NAS),and other real-worldmulti-objective problems.For Multi-objective PIO(MPIO),key improvements include controlling the growth of the external archive and designing more effective selection mechanisms to maintain convergence efficiency.These efforts are expected to strengthen both the theoretical foundation and practical versatility of PIO and its variants. 展开更多
关键词 Pigeon-inspired optimization metaheuristic algorithm algorithmvariants swarmintelligence variantS UAVS convergence analysis
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Association of conventional chromosomal polymorphic variants in 580 couples with idiopathic recurrent pregnancy loss:A retrospective cohort study
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作者 Sunny Kumar Jignesh Kumar Patel Amit Roy Chowdhury +2 位作者 Shagufa Sheikh Purna Chandra Mahapatra Birendranath Banerjee 《Asian pacific Journal of Reproduction》 2026年第1期11-22,共12页
Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Ph... Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss. 展开更多
关键词 Polymorphic variants Chromosomal anomalies Repeated pregnancy loss Cytogenetic investigation
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A novel CRB1 variant presenting as Leber congenital amaurosis-8 with angle-closure glaucoma in a Chinese family
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作者 Gong Chen Zhi-Ruo Wang +2 位作者 Cong Zhao Hui-Hui Chen Jing-Ming Shi 《International Journal of Ophthalmology(English edition)》 2026年第3期630-633,共4页
Dear Editor,We reported a Chinese family carrying a novel Crumbs homologue 1(CRB1)variant(c.1737_1755del).Consanguineous marriage resulted in a homozygous mutation,leading to the onset of Leber congenital amaurosis(LC... Dear Editor,We reported a Chinese family carrying a novel Crumbs homologue 1(CRB1)variant(c.1737_1755del).Consanguineous marriage resulted in a homozygous mutation,leading to the onset of Leber congenital amaurosis(LCA)in their offspring. 展开更多
关键词 crb variant homozygous mutationleading Chinese family Leber congenital amaurosis angle closure glaucoma homozygous mutation consanguineous marriage leber congenital amaurosis lca
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Novel characterization of NADC30-like and NADC34-like PRRSV strains in China:Epidemiological status and pathogenicity analysis of L1A variants
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作者 Hu Xu Siyu Zhang +18 位作者 Zhenyang Guo Chao Li Bangjun Gong Jinhao Li Qi Sun Jing Zhao MenglinZhang Lirun Xiang Yandong Tang Chaoliang Leng Jianan Wu Qian Wang Jinmei Peng GuohuiZhou Huairan Liu Tongqing An Xuehui Cai Zhijun Tian Hongliang Zhang 《Journal of Integrative Agriculture》 2026年第1期235-246,共12页
NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-l... NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China. 展开更多
关键词 NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV) NADC30-like PRRSV L1A variant recombination PATHOGENICITY
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Effectiveness and safety of traditional Chinese herbs in children with cough variant asthma: a systematic review and Meta-analysis 被引量:13
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作者 Kyou-Hwan Han Ki Haeng Cho +2 位作者 CUI Shanqin Lily Lin Jaejong Kim 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2021年第5期661-668,共8页
OBJECTIVE:To systematically investigate the clinical effectiveness and safety of traditional Chinese herbs(TCHs)as an alternative to conventional medicine(CM)in children with cough variant asthma(CVA).METHODS:Randomiz... OBJECTIVE:To systematically investigate the clinical effectiveness and safety of traditional Chinese herbs(TCHs)as an alternative to conventional medicine(CM)in children with cough variant asthma(CVA).METHODS:Randomized controlled trial(RCT)studies that were published from their inceptions to March 31,2020,were identified from the electronic databases of China National Knowledge Infrastructure,Wangfang,Pub Med,and Cochrane Central Library.The primary outcome of the review was the total effective rate(TER),and the secondary outcomes were immunoglobulin E(Ig E),peak expiratory flow(PEF),adverse drug reactions,and relapse rates of interventions.RESULTS:For the Meta-analysis,13 studies involving 992 children with CVA were included.In terms of TER and Ig E,the experimental interventions of TCH,when compared with the control interventions of CM,on pediatric CVA were found to be significantly effective(P<0.0001),whereas for spirometry,PEF was not significantly improved in the TCH group(P=0.48).The incident rates of adverse drug reaction and relapse were found to be significantly lower in the TCH group than those in the CM group(P=0.02 and P<0.0001,respectively).CONCLUSION:Compared with CM therapy,the effects of TCH therapy on pediatric CVA were significantly beneficial in terms of TER and Ig E,but not for PEF,and the methodological quality of included studies was poor.Therefore,the results should be interpreted with caution.More randomized controlled trials with rigorous experimental methodologies are required for objectivity in the future. 展开更多
关键词 cough variant asthma CHILD drugs Chinese herbal randomized controlled trial systematic review META-ANALYSIS
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Systematic identification and annotation of multiple-variant compound effects at transcription factor binding sites in human genome 被引量:1
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作者 Si-Jin Cheng Shuai Jiang +2 位作者 Fang-Yuan Shi Yang Ding Ge Gao 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2018年第7期373-379,共7页
Understanding the functional effects of genetic variants is crucial in modern genomics and genetics. Transcription factor binding sites (TFBSs) are one of the most important cis-regulatory elements. While multiple t... Understanding the functional effects of genetic variants is crucial in modern genomics and genetics. Transcription factor binding sites (TFBSs) are one of the most important cis-regulatory elements. While multiple tools have been developed to assess functional effects of genetic variants at TFBSs, they usually assume that each variant works in isolation and neglect the potential "interference" among multiple variants within the same TFBS. In this study, we presented COPE-TFBS (Context-Oriented Predictor for variant Effect on Transcription Factor Binding Site), a novel method that considers sequence context to accurately predict variant effects on TFBSs. We systematically re-analyzed the sequencing data from both the 1000 Genomes Project and the Genotype-Tissue Expression (GTEx) Project via COPE-TFBS, and identified numbers of novel TFBSs, transformed TFBSs and discordantly annotated TFBSs resulting from multiple variants, further highlighting the necessity of sequence context in accurately annotating genetic variants. 展开更多
关键词 Compound effect Transcription factor binding site variant annotation BIOINFORMATICS Genetic variants
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Variant Map System to Simulate Complex Properties of DNA Interactions Using Binary Sequences 被引量:1
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作者 Jeffrey Zheng Weiqiong Zhang +2 位作者 Jin Luo Wei Zhou Ruoyu Shen 《Advances in Pure Mathematics》 2013年第7期5-24,共20页
Stream cipher, DNA cryptography and DNA analysis are the most important R&D fields in both Cryptography and Bioinformatics. HC-256 is an emerged scheme as the new generation of stream ciphers for advanced network ... Stream cipher, DNA cryptography and DNA analysis are the most important R&D fields in both Cryptography and Bioinformatics. HC-256 is an emerged scheme as the new generation of stream ciphers for advanced network security. From a random sequencing viewpoint, both sequences of HC-256 and real DNA data may have intrinsic pseudo-random properties respectively. In a recent decade, many DNA sequencing projects are developed on cells, plants and animals over the world into huge DNA databases. Researchers notice that mammalian genomes encode thousands of large noncoding RNAs (lncRNAs), interact with chromatin regulatory complexes, and are thought to play a role in localizing these complexes to target loci across the genome. It is a challenge target using higher dimensional visualization tools to organize various complex interactive properties as visual maps. The Variant Map System (VMS) as an emerging scheme is systematically proposed in this paper to apply multiple maps that used four Meta symbols as same as DNA or RNA representations. System architecture of key components and core mechanism on the VMS are described. Key modules, equations and their I/O parameters are discussed. Applying the VM System, two sets of real DNA sequences from both sample human (noncoding DNA) and corn (coding DNA) genomes are collected in comparison with pseudo DNA sequences generated by HC-256 to show their intrinsic properties in higher levels of similar relationships among relevant DNA sequences on 2D maps. Sample 2D maps are listed and their characteristics are illustrated under controllable environment. Visual results are briefly analyzed to explore their intrinsic properties on selected genome sequences. 展开更多
关键词 PSEUDO-RANDOM Number Generator STREAM CIPHER HC-256 Binary to DNA Pseudo DNA Sequence Large Noncoding DNA Analysis 2D MAP Visual Distribution variant MAP system
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Computer-Aided Rapid Variant Design System for Hydraulic Support
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作者 赵继云 李炳文 +1 位作者 苗运江 顾力强 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期153-156,共4页
The paper gives a detail analysis on the necessity of rapid hydraulic support design, and presents a computer-aided rapid variant design system for hydraulic support. The system integrates the type selection and embod... The paper gives a detail analysis on the necessity of rapid hydraulic support design, and presents a computer-aided rapid variant design system for hydraulic support. The system integrates the type selection and embodiment design of hydraulic support. Case-based reasoning and rule-based reasoning are the main reasoning methods. Several crucial problems are discussed. 展开更多
关键词 HYDRAULIC support CAD variant design case-based REASONING RULE-BASED REASONING
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A Novel CAPP System Based on SML for Variant Design of Process Planning
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作者 ZHAO Haibin WANG Junying ZHANG Min 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期820-823,共4页
The production model of“multi-specification and low-quantity”is becoming the main trend of manufacturing industry.As a key activity in the manufacturing chain,traditional computer aided process planning(CAPP)system ... The production model of“multi-specification and low-quantity”is becoming the main trend of manufacturing industry.As a key activity in the manufacturing chain,traditional computer aided process planning(CAPP)system fails to adapt to the production model of customization.Therefore,a novel method for variant design of process planning was proposed to develop CAPP system based on Tabular Layouts of Article Characteristics(Sach-Merk Leisten in German and SML for short).With the support of standard database of master process planning documents which are developed by parameterization technique,and instance process planning for special product(instance product)can be generated automatically by the sub-system of variant de-sign of process planning.Finally,a CAPP system was developed for process design of rotor of steam turbine to validate the feasibil-ity and applicability of the method. 展开更多
关键词 CAPP variant design SML master process planning documents(DocMPP) PARAMETERIZATION
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GENERALIZED BIANCHI'S IDENTITIES FOR VARIANT CONSTRAINED SYSTEM
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作者 李子平 《Acta Mathematica Scientia》 SCIE CSCD 1992年第3期241-247,共7页
In this paper the generalized Bianchi's identities for the variant constrained system (GBIVOS)w ith non-invariant action integral and constraint conditions was derived, and the strong and weak conservation laws fo... In this paper the generalized Bianchi's identities for the variant constrained system (GBIVOS)w ith non-invariant action integral and constraint conditions was derived, and the strong and weak conservation laws for such system was deduced. The preliminary applications of the GBIVCS to the case for some models of field theories was given. The Dirac constraint of such system was discussed. 展开更多
关键词 GENERALIZED BIANCHI’S IDENTITIES FOR variant CONSTRAINED system der
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Asian variant intravascular large B-cell lymphoma with highly suspected central nervous system involvement:A case report
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作者 Yong-Pyo Lee Seung-Myoung Son Jihyun Kwon 《World Journal of Clinical Cases》 SCIE 2023年第33期8058-8064,共7页
BACKGROUND Intravascular large B-cell lymphoma(IVLBCL)is a rare subtype of extranodal lymphoma.In particular,the Asian variant of IVLBCL is characterized by hemophagocytic lymphohistiocytosis along with bone marrow in... BACKGROUND Intravascular large B-cell lymphoma(IVLBCL)is a rare subtype of extranodal lymphoma.In particular,the Asian variant of IVLBCL is characterized by hemophagocytic lymphohistiocytosis along with bone marrow involvement.However,central nervous system(CNS)involvement is uncommon in this variant compared to the Western variant.Here,we report a case of typical Asian variant IVLBCL with highly suspected CNS involvement and discuss the nature of the disease and its genetic aberration.CASE SUMMARY A 67-year-old female patient complained of gradually worsening cognitive impairment.While hospitalized,she developed a high fever and showed marked bicytopenia.Intracranial imaging revealed a suspected leptomeningeal disease.Although no malignant cells were found in the cerebrospinal fluid(CSF),the protein and lactate dehydrogenase levels in CSF were increased.Bone marrow examination revealed an increased number of hemophagocytic histiocytes,and 18F-fluorodeoxyglucose(FDG)positron emission tomography with computerized tomography scan revealed increased FDG uptake in both adrenal glands,the liver,and the right ethmoid sinus.A tissue biopsy showed atypical large lymphoid cells with prominent nucleoli in the vessels,and the tumor cells were positive for CD20,BCL2,BCL6,and IRF4/MUM1.In addition,targeted sequencing identified MYD88,TET2,and PIM1 mutations.Consequently,we diagnosed the patient with the Asian variant of IVLBCL with highly suspected CNS involvement.CONCLUSION Suspicion of IVLBCL and immediate diagnosis lead to timely treatment.Moreover,careful CNS examination at diagnosis is recommended. 展开更多
关键词 Intravascular large B-cell lymphoma Asian variant Hemophagocytic lymphohistiocytosis Central nervous system involvement Genetic alteration Case report
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Genetic variants associated with endometriosis patients:a systematic review
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作者 Bo Hu Xin jin +4 位作者 Guang-Tao Xu Ping Qian Long Xu Li-Min Jin De-Qing Chen 《Precision Medicine Research》 2021年第1期7-20,共14页
Endometriosis is defined as the presence of endometrium-like tissue outside the uterus,80%of which occur in the ovaries.It is characterized by an estrogen-dependent produces periodic and repeated bleeding,and may be a... Endometriosis is defined as the presence of endometrium-like tissue outside the uterus,80%of which occur in the ovaries.It is characterized by an estrogen-dependent produces periodic and repeated bleeding,and may be accompanied by clinical symptoms such as dysmenorrhea,fatigue,dysuria,deep dyspareunia,and infertility.Due to the complex etiology and the yet-unknown pathogenesis of endometriosis,and the treatment effect is not ideal,causing significant physical and mental harm to reproductive-age women;thus,it has become a hot research topic.Endometriosis is still a mysterious disease of unknown origin and pathogenesis.Genetic factors are known to affect the manifestation and progression of endometriosis.A selection of genetic studies revealed genetic mutations and polymorphisms of endometriosis and their effects on the risk of developing this disease.This paper aimed to discuss the genetic variants associated with the risk of endometriosis and provided information to enrich the gene spectrum of endometriosis. 展开更多
关键词 ENDOMETRIOSIS Genetic variants Single nucleotide polymorphism
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3'untranslated region somatic variants connect alternative polyadenylation dysregulation in human cancers 被引量:1
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作者 Qiushi Xu Xiaomeng Cheng +6 位作者 Qianru Li Peng Yu Xiaolan Zhou Yu Chen Limin Lin Ting Ni Zhaozhao Zhao 《Journal of Genetics and Genomics》 2025年第11期1376-1386,共11页
Somatic variants in the cancer genome influence gene expression through diverse mechanisms depending on their specific locations.However,a systematic evaluation of the effects of somatic variants located in 3'untr... Somatic variants in the cancer genome influence gene expression through diverse mechanisms depending on their specific locations.However,a systematic evaluation of the effects of somatic variants located in 3'untranslated regions(3'UTRs)on alternative polyadenylation(APA)of m RNA remains lacking.In this study,we analyze 10,199 tumor samples across 32 cancer types and identify 1333 somatic single nucleotide variants(SNVs)associated with abnormal 3'UTR APA.Mechanistically,these 3'UTR SNVs can alter cisregulatory elements,such as the poly(A)signal and UGUA motif,leading to changes in APA.Minigene assays confirm that 3'UTR SNVs in multiple genes,including RPS23 and CHTOP,induce aberrant APA.Among affected genes,62 exhibit differential stability between tandem 3'UTR isoforms,including HSPA4and UCK2,validated by experimental assays.Finally,we establish that SNV-related abnormal APA usage serves as an additional layer of expression regulation for tumor-suppressor gene HMGN2 in breast cancer.Collectively,this study reveals 3'UTR APA as a critical mechanism mediating the functional impact of somatic noncoding variants in human cancers. 展开更多
关键词 Somatic variants 3'UTR Alternative polyadenylation CANCER Gene expression regulation
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A quasi-in-situ EBSD study on mechanical response and twin variant selection of a hot-rolled AZ31 magnesium alloy 被引量:1
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作者 Huicong Chen Chenwei Shao +2 位作者 Lijun Wang Hao Chen Yu Zou 《Journal of Magnesium and Alloys》 2025年第4期1549-1560,共12页
The selection of twin variants plays a critical role in shaping the deformation texture and mechanical properties of magnesium alloys that are limited by slip systems and diverse twinning modes.In this study,we invest... The selection of twin variants plays a critical role in shaping the deformation texture and mechanical properties of magnesium alloys that are limited by slip systems and diverse twinning modes.In this study,we investigated the twin variant selection and the effect of twinning activity on the strain hardening of a hot-rolled AZ31 magnesium alloy by quasi-in-situ EBSD.Moreover,the Schmid factors and the displacement gradient tensors were computed to evaluate the activation of twin variants.The results reveal that the yield strength increased progressively after each deformation step,driven by grain subdivision and texture hardening induced by extension{1012}twinning and the Basinski effect at large strains.The nucleation and growth of the{1012}twins occurred either sequentially or simultaneously during the plastic deformation.At low plastic strains,the activation of most twin variants followed the high Schmid factor criterion while the other twin variants with lower Schmid factors were activated due to the interactions with preexisting twins characterized by high misorientation angles(around 60°).Additionally,this non-Schmid factor scenario was also attributed to low coordinated strain requirements from neighboring grains,showing the critical role of local deformation accommodation in the twinning process.These findings advance the fundamental understanding of the twin variant selection and its implications for the microstructure-property relationship in magnesium alloys for structural applications. 展开更多
关键词 Magnesium alloy Strain hardening Twin variants Schmid factor Strain accommodation
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Tailoring bande d-equiaxe d heterogeneous structure and martensite variants to achieve high toughness and high ductility in a newly designed 2.4 GPa high-strength steel 被引量:1
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作者 Jiale Jiang Yunjie Li +4 位作者 Yi Liu Jian Kang Xiaolin Li Guo Yuan Guodong Wang 《Journal of Materials Science & Technology》 2025年第28期270-285,共16页
Ultra-high strength steels with a strength level of 2000 MPa are critical structural materials for some extreme service environments but face problems of low ductility and bad toughness.Current research effort s often... Ultra-high strength steels with a strength level of 2000 MPa are critical structural materials for some extreme service environments but face problems of low ductility and bad toughness.Current research effort s often focus on improving individual property,such as elongation or toughness.Therefore,it re-mains a significant challenge to unify both features of high strength,high ductility,and high toughness in one material.Adding precious metals such as Ni and Co and using aging treatment can achieve good strength and ductility in the maraging steels,but the cost is too high.In this study,we report a lean 2.4 GPa ultra-high-strength steel with a uniform elongation of 7.7%and a V-notched impact toughness of 29 J/cm^(2),which shows a competitive advantage compared with existing aircraft landing gear steels.The alloy composition design of“Mn+microalloying”and simple possessing route of quenching,deep cryo-genic treatment,and low-temperature annealing(Q-D-L)are used to achieve low-cost preparation.The transformation behaviors and mechanisms of strengthening,ductilizing,and toughening are discussed.The developed steel possesses a fine banded-equiaxed heterogeneous original austenite structure,where the CP4 occupies most of the equiaxed austenite,with more high-angle grain boundaries,and the marten-sitic variant of the banded structure is selectively weakened,resulting in a more uniform deformation,so that the crack nucleation energy and propagation energy can be simultaneously improved.Besides,the low aspect ratio structure originating from the fine parent austenite is beneficial to stimulating out-of-lath plane and in-lath plane multiple slip systems,compared with the coarse martensite with geometric lath constraints,thus increasing the deformation capability of martensite.Consequently,with the yield strength of the sample increased to 1960 MPa,the uniform elongation remained as high as 7.7%,indi-cating a notable improvement in both strength and ductility compared to samples with coarse banded austenite structures(1718 MPa&7.6%).This study provides new insights into alloy design and processing strategies for the synergistic enhancement of multiple properties in ultra-high-strength steels. 展开更多
关键词 2.4 GPa martensitic steel High ductility and high toughness Original austenite Martensitic variant Crack propagation
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The effectiveness and safety of HuangQiXiXin decoction for cough variant asthma:protocol for a systematic review
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作者 Qing-Qing Xia Cong Wang +2 位作者 Yu-Feng Zhang Wei-Long Jiang Jia Qi 《Clinical Research Communications》 2022年第2期5-8,共4页
Objective:A comprehensive and updated systematic review is needed to evaluate the effectiveness and safety of HuangQiXiXin decoction(HQXXD)for cough variant asthma(CVA).The aim of this systematic review protocol is to... Objective:A comprehensive and updated systematic review is needed to evaluate the effectiveness and safety of HuangQiXiXin decoction(HQXXD)for cough variant asthma(CVA).The aim of this systematic review protocol is to comprehensively assess the effectiveness and safety of HQXXD for CVA.Methods:An overall search for studies in main English and Chinese electronic databases from their inception to January 2021 will be performed.Randomized controlled trials regarding HQXXD for CVA will be included.We will use RevMan 5.3 software to perform statistical analysis and meta-analysis.Results:The findings of this systematic review will be disseminated through peer-reviewed publications.Conclusion:The systematic review will provide more evidence regarding the effectiveness and safety of HQXXD for CVA. 展开更多
关键词 HuangQiXiXin decoction cough variant asthma PROTOCOL systematic review
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Unveiling mitochondrial mysteries:Exploring novel tRNA variants in type 2 diabetes mellitus
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作者 Chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng 《World Journal of Diabetes》 SCIE 2025年第1期1-6,共6页
The recent study of Ding et al provides valuable insights into the functional implications of novel mitochondrial tRNATrp and tRNASer(AGY)variants in type 2 diabetes mellitus(T2DM).This editorial explores their findin... The recent study of Ding et al provides valuable insights into the functional implications of novel mitochondrial tRNATrp and tRNASer(AGY)variants in type 2 diabetes mellitus(T2DM).This editorial explores their findings,highlighting the role of mitochondrial dysfunction in the pathogenesis of T2DM.By examining the molecular mechanisms through which these tRNA variants contribute to disease progression,the study introduces new targets for therapeutic strategies.We discuss the broader implications of these results,emphasizing the importance of understanding mitochondrial genetics in addressing T2DM. 展开更多
关键词 Mitochondrial tRNA variants Type 2 diabetes mellitus Mitochondrial dysfunction Genetic markers Therapeutic strategies
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Perturbation to Mei symmetry and Mei adiabatic invariants for discrete generalized Birkhoffian system 被引量:2
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作者 张克军 方建会 李燕 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期305-309,共5页
Based on the concept of discrete adiabatic invariant, this paper studies the perturbation to Mei symmetry and Mei adiabatic invariants of the discrete generalized Birkhoffian system. The discrete Mei exact invariant i... Based on the concept of discrete adiabatic invariant, this paper studies the perturbation to Mei symmetry and Mei adiabatic invariants of the discrete generalized Birkhoffian system. The discrete Mei exact invariant induced from the Mei symmetry of the system without perturbation is given. The criterion of the perturbation to Mei symmetry is established and the discrete Mei adiabatic invariant induced from the perturbation to Mei symmetry is obtained. Meanwhile, an example is discussed to illustrate the application of the results. 展开更多
关键词 discrete generalized Birkhoffian system Mei symmetry PERTURBATION Mei adiabatic in-variant
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