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Phenotypic advantages and improved genomic stability following selection in advanced selfing-generations of Brassica allohexaploids
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作者 Yan Niu Rui Yang +9 位作者 Zelong Li Zhengxuan Huo Shihao Chang Entang Tian Han Qin Wallace A.Cowling Kadambot H.M.Siddique Annaliese S.Mason Sheng Chen jun zou 《Journal of Genetics and Genomics》 2025年第6期799-811,共13页
Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combinin... Allopolyploids often exhibit advantages in vigor and adaptability compared to diploids.A long-term goal in the economically important Brassica genus has been to develop a new allohexaploid crop type(AABBCC)by combining different diploid and allotetraploid crop species.However,early-generation allohexaploids often face challenges like unstable meiosis and low fertility,and the phenotypic performance of these synthetic lines has rarely been assessed.This study analyzes agronomic traits,fertility,and genome stability in ArArBcBcCcCc lines derived from four crosses between B.carinata and B.rapa after 9–11 selfing generations.Our results demonstrate polyploid advantage in vigor and seed traits,considerable phenotypic variation,and high fertility and genome stability.Meanwhile,parental genotypes significantly influence outcomes in advanced allohexaploids.Structural variants,largely resulting from A–C homoeologous exchanges,contribute to genomic variation and influence hexaploid genome stability,with the A sub-genome showing the highest variability.Both positive and negative impacts of SVs on fertility and seed weight are observed.Pseudo-euploids,frequently appearing,do not significantly affect fertility or other agronomic traits compared to euploids,indicating a potential pathway toward a stable allohexaploid species.These findings provide insights into the challenge and potential for developing an adaptable and stable Brassica hexaploid through selection. 展开更多
关键词 Brassica species Synthetic allohexaploid Homoeologous exchange Genome stability Polyploid advantage Structural variants
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Autophagy in erectile dysfunction:focusing on apoptosis and fibrosis
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作者 Pei-Yue Luo jun-Rong zou +6 位作者 Tao Chen jun zou Wei Li Qi Chen Le Cheng Li-Ying Zheng Biao Qian 《Asian Journal of Andrology》 2025年第2期166-176,共11页
In most types of erectile dysfunction,particularly in advanced stages,typical pathological features observed are reduced parenchymal cells coupled with increased tissue fibrosis.However,the current treatment methods h... In most types of erectile dysfunction,particularly in advanced stages,typical pathological features observed are reduced parenchymal cells coupled with increased tissue fibrosis.However,the current treatment methods have shown limited success in reversing these pathologic changes.Recent research has revealed that changes in autophagy levels,along with alterations in apoptosis and fibrosis-related proteins,are linked to the progression of erectile dysfunction,suggesting a significant association.Autophagy,known to significantly affect cell fate and tissue fibrosis,is currently being explored as a potential treatment modality for erectile dysfunction.However,these present studies are still in their nascent stage,and there are limited experimental data available.This review analyzes erectile dysfunction from a pathological perspective.It provides an in-depth overview of how autophagy is involved in the apoptotic processes of smooth muscle and endothelial cells and its role in the fibrotic processes occurring in the cavernosum.This study aimed to develop a theoretical framework for the potential effectiveness of autophagy in preventing and treating erectile dysfunction,thus encouraging further investigation among researchers in this area. 展开更多
关键词 APOPTOSIS AUTOPHAGY erectile dysfunction FIBROSIS oxidative stress
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Roles of lncRNA in the crosstalk between osteogenesis and angiogenesis in the bone microenvironment
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作者 Shihua ZHANG Jianmin GUO +6 位作者 Yuting HE Zhi’ang SU Yao FENG Lan ZHANG jun zou Xiquan WENG Yu YUAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第2期107-123,共17页
Bone is a highly calcified and vascularized tissue.The vascular system plays a vital role in supporting bone growth and repair,such as the provision of nutrients,growth factors,and metabolic waste transfer.Moreover,th... Bone is a highly calcified and vascularized tissue.The vascular system plays a vital role in supporting bone growth and repair,such as the provision of nutrients,growth factors,and metabolic waste transfer.Moreover,the additional functions of the bone vasculature,such as the secretion of various factors and the regulation of bone-related signaling pathways,are essential for maintaining bone health.In the bone microenvironment,bone tissue cells play a critical role in regulating angiogenesis,including osteoblasts,bone marrow mesenchymal stem cells(BMSCs),and osteoclasts.Osteogenesis and bone angiogenesis are closely linked.The decrease in osteogenesis and bone angiogenesis caused by aging leads to osteoporosis.Long noncoding RNAs(lncRNAs)are involved in various physiological processes,including osteogenesis and angiogenesis.Recent studies have shown that lncRNAs could mediate the crosstalk between angiogenesis and osteogenesis.However,the mechanism by which lncRNAs regulate angiogenesis-osteogenesis crosstalk remains unclear.In this review,we describe in detail the ways in which lncRNAs regulate the crosstalk between osteogenesis and angiogenesis to promote bone health,aiming to provide new directions for the study of the mechanism by which lncRNAs regulate bone metabolism. 展开更多
关键词 Long noncoding RNA(lncRNA) OSTEOGENESIS Bone angiogenesis OSTEOPOROSIS Bone microenvironment
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多臂聚-D-乳酸的合成与表征
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作者 邹俊 李鑫 +2 位作者 徐海青 张宜辉 苏乐乐 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第7期35-40,47,共7页
以右旋丙交酯(D-LA)与八环氧笼型多面体低聚倍半硅氧烷(EPOSS)为原料,辛酸亚锡(Sn(Oct)2)为催化剂,无水二甲苯为溶剂,通过原位开环聚合法制备多臂聚-D-乳酸(PDLA-EPOSS),通过红外光谱、核磁共振、X射线衍射、凝胶渗透色谱、动态力学分... 以右旋丙交酯(D-LA)与八环氧笼型多面体低聚倍半硅氧烷(EPOSS)为原料,辛酸亚锡(Sn(Oct)2)为催化剂,无水二甲苯为溶剂,通过原位开环聚合法制备多臂聚-D-乳酸(PDLA-EPOSS),通过红外光谱、核磁共振、X射线衍射、凝胶渗透色谱、动态力学分析和热重分析研究了不同含量EPOSS对PDLA-EPOSS的化学结构、晶体结构、分子链结构、重均相对分子质量及其分布(PDI)和性能的影响。结果表明,成功合成了具有多臂支化结构、晶体结构与PDLA相同、相对分子质量可控且相对分子质量分布较窄、热稳定性良好的PDLA-EPOSS共聚物。并且随着EPOSS含量的增加,PDLA-EPOSS的重均相对分子质量先增加后减小、PDI增加、储能模量与损耗因子增加,热分解温度先升高后下降。在EPOSS摩尔分数为5.0×10-5%时,共聚物的相对分子质量与热分解温度最高,分别为1.27×106、287.73℃。这些结果对于研究PDLA-EPOSS对PLLA结晶性能的影响有一定的参考价值。 展开更多
关键词 右旋丙交酯 八环氧笼型多面体低聚倍半硅氧烷 多臂聚-D-乳酸 相对分子质量可控
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Monitoring somatosensory evoked potentials in spinal cord ischemia-reperfusion injury 被引量:7
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作者 Yiming Ji Bin Meng +2 位作者 Chenxi Yuan Huilin Yang jun zou 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第33期3087-3094,共8页
It remains unclear whether spinal cord ischemia-reperfusion injury caused by ischemia and other non-mechanical factors can be monitored by somatosensory evoked potentials. Therefore, we monitored spinal cord ischemia-... It remains unclear whether spinal cord ischemia-reperfusion injury caused by ischemia and other non-mechanical factors can be monitored by somatosensory evoked potentials. Therefore, we monitored spinal cord ischemia-reperfusion injury in rabbits using somatosensory evoked potential detection technology. The results showed that the somatosensory evoked potential latency was significantly prolonged and the amplitude significantly reduced until it disappeared during the period of spinal cord ischemia. After reperfusion for 30-180 minutes, the amplitude and latency began to gradually recover; at 360 minutes of reperfusion, the latency showed no significant difference compared with the pre-ischemic value, while the somatosensory evoked potential amplitude in- creased, and severe hindlimb motor dysfunctions were detected. Experimental findings suggest that changes in somatosensory evoked potentia~ ~atency can reflect the degree of spinat cord ischemic injury, while the amplitude variations are indicators of the late spinal cord reperfusion injury, which provide evidence for the assessment of limb motor function and avoid iatrogenic spinal cord injury. 展开更多
关键词 neural regeneration spinal cord injury somatosensory evoked potentials spinal cord ischemia REPERFUSION iatrogenic spinal cord injury HISTOPATHOLOGY abdominal aorta occlusion model latency grants-supported paper NEUROREGENERATION
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Endoscopic findings of gastrointestinal involvement in Chinese patients with Behcet's disease 被引量:13
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作者 jun zou Yan Shen +2 位作者 Da-Nian Ji Song-Bai Zheng Jian-Long Guan 《World Journal of Gastroenterology》 SCIE CAS 2014年第45期17171-17178,共8页
AIM:To report the incidence,clinical features and outcomes of gastrointestinal(GI)involvement in Behcet’s disease(BD).METHODS:A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopi... AIM:To report the incidence,clinical features and outcomes of gastrointestinal(GI)involvement in Behcet’s disease(BD).METHODS:A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopies were performed in 148 patients.Four hundred age-and sex-matched controls were enrolled for comparison.RESULTS:Fifty-two(35.1%)patients had GI lesions.After a mean follow-up of 10 mo,ileocecal ulcers had been confirmed in 20 patients,including active ulcer(s)in 18 patients,but no ileocecal ulceration was found in controls.GI symptoms were present in 14 patients with active ulcer(s),while 4 patients with smaller ulcer were asymptomatic.Endoscopic features of ileocecalulcer were:a single ulcer(50%),larger than 1 cm in diameter(72.2%),and round/oval or volcano-type in shape(83.3%).Compared with patients without GI involvement,less ocular lesions,lower levels of albumin,erythrocyte count and hemoglobin,and higher levels of C-reactive protein and erythrocyte sedimentation rate were confirmed in the intestinal BD group.Four patients had esophageal ulcers in the BD group but no case in controls.The other endoscopic findings were similar between the two groups.The prevalence of Helicobacter pylori infection was similar in both groups.Most patients received an immunomodulator and responded well.CONCLUSION:GI lesions commonly occur in Chinese BD patients.The most frequently involved area is the ileocecal region.Esophageal ulcer might be a rare but unique lesion. 展开更多
关键词 Behcet's disease Gastrointestinal involve-ment ULCER ENDOSCOPY Case-controlled
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Observation-based Estimation of Aerosol-induced Reduction of Planetary Boundary Layer Height 被引量:9
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作者 jun zou Jianning SUN +3 位作者 Aijun DING Minghuai WANG Weidong GUO Congbin FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1057-1068,共12页
Radiative aerosols are known to influence the surface energy budget and hence the evolution of the planetary boundary layer. In this study, we develop a method to estimate the aerosol-induced reduction in the planetar... Radiative aerosols are known to influence the surface energy budget and hence the evolution of the planetary boundary layer. In this study, we develop a method to estimate the aerosol-induced reduction in the planetary boundary layer height (PBLH) based on two years of ground-based measurements at a site, the Station for Observing Regional Processes of the Earth System (SORPES), at Nanjing University, China, and radiosonde data from the meteorological station of Nanjing. The observations show that increased aerosol loads lead to a mean decrease of 67.1 W m-2 for downward shortwave radiation (DSR) and a mean increase of 19.2 W m-2 for downward longwave radiation (DLR), as well as a mean decrease of 9.6 W m-2 for the surface sensible heat flux (SHF) in the daytime. The relative variations of DSR, DLR and SHF are shown as a function of the increment of column mass concentration of particulate matter (PM2.5). High aerosol loading can significantly increase the atmospheric stability in the planetary boundary layer during both daytime and nighttime. Based on the statistical relationship between SHF and PM2.5 column mass concentrations, the SHF under clean atmospheric conditions (same as the background days) is derived. In this case, the derived SHF, together with observed SHF, are then used to estimate changes in the PBLH related to aerosols. Our results suggest that the PBLH decreases more rapidly with increasing aerosol loading at high aerosol loading. When the daytime mean column mass concentration of PM2.5 reaches 200 mg m-2, the decrease in the PBLH at 1600 LST (local standard time) is about 450 m. 展开更多
关键词 AEROSOL RADIATION atmospheric stability surface sensible heat flux planetary boundary layer height
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选区激光熔化成形件磨损特性综述(英文) 被引量:6
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作者 Yi ZHU jun zou Hua-yong YANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2018年第2期95-110,共16页
通过对文献的综述,本文总结了已有的选区激光熔化成形件的磨损特性研究,并提出了未来的研究方向,为该技术成形摩擦副的推广提供参考。本文通过干磨、边界润滑下的磨损、腐蚀以及冲蚀四个方面介绍了已有研究。总体来看,选区激光熔化成形... 通过对文献的综述,本文总结了已有的选区激光熔化成形件的磨损特性研究,并提出了未来的研究方向,为该技术成形摩擦副的推广提供参考。本文通过干磨、边界润滑下的磨损、腐蚀以及冲蚀四个方面介绍了已有研究。总体来看,选区激光熔化成形件得益于均匀细晶,高致密度成形件的磨损率普遍低于传统制造件,然而孔隙的出现将降低成形件的抗磨性能。未来的研究内容主要包括孔隙对润滑的影响规律及其机理,以及如何通过主动控制激光工艺参数提高选区激光熔化成形件的抗磨能力。 展开更多
关键词 选区激光熔化 磨损 增材制造 润滑 孔隙
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Analysis of the TCM theory of traditional Chinese health exercise 被引量:6
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作者 Yan Jiang jun zou 《Journal of Sport and Health Science》 SCIE 2013年第4期204-208,共5页
The traditional Chinese medicine(TCM)theory of traditional Chinese health exercise(TCHE)is analyzed.The effect of meridians and acupoints contained in TCHE is summarized,the treatment methods of tonifying deficiencies... The traditional Chinese medicine(TCM)theory of traditional Chinese health exercise(TCHE)is analyzed.The effect of meridians and acupoints contained in TCHE is summarized,the treatment methods of tonifying deficiencies and reducing excesses applied in TCHE are discussed,the regulation of Zang-fu organs are emphasized,and the leading role of Qi is introduced.The exercise prescription and proper timing of TCHE are described and reported.TCHEs,such as Baduanjin,Liuzijue,and Tai Chi,possess strong TCM characteristics. 展开更多
关键词 TRADITIONAL CHINESE HEALTH EXERCISE TRADITIONAL CHINESE MEDICINE THEORY
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Advances in the study of mitophagy in osteoarthritis 被引量:5
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作者 Hong CAO Xuchang ZHOU +5 位作者 Bowen XU Han HU Jianming GUO Miao WANG Nan LI jun zou 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2024年第3期197-211,共15页
Osteoarthritis(OA),characterized by cartilage degeneration,synovial inflammation,and subchondral bone remodeling,is among the most common musculoskeletal disorders globally in people over 60 years of age.The initiatio... Osteoarthritis(OA),characterized by cartilage degeneration,synovial inflammation,and subchondral bone remodeling,is among the most common musculoskeletal disorders globally in people over 60 years of age.The initiation and progression of OA involves the abnormal metabolism of chondrocytes as an important pathogenic process.Cartilage degeneration features mitochondrial dysfunction as one of the important causative factors of abnormal chondrocyte metabolism.Therefore,maintaining mitochondrial homeostasis is an important strategy to mitigate OA.Mitophagy is a vital process for autophagosomes to target,engulf,and remove damaged and dysfunctional mitochondria,thereby maintaining mitochondrial homeostasis.Cumulative studies have revealed a strong association between mitophagy and OA,suggesting that the regulation of mitophagy may be a novel therapeutic direction for OA.By reviewing the literature on mitophagy and OA published in recent years,this paper elaborates the potential mechanism of mitophagy regulating OA,thus providing a theoretical basis for studies related to mitophagy to develop new treatment options for OA. 展开更多
关键词 MITOPHAGY OSTEOARTHRITIS CHONDROCYTE MITOCHONDRIA APOPTOSIS
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Fluid-driven artificialmuscles: bio-design, manufacturing, sensing, control, and applications 被引量:5
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作者 Chao Zhang Pingan Zhu +4 位作者 Yangqiao Lin Wei Tang Zhongdong Jiao Huayong Yang jun zou 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第1期123-145,共23页
Developing artificial muscles that can replace biological muscles to accomplish various tasks iswhat we have long been aiming for.Recent advances in flexible materials and 3D printing technology greatly promote the de... Developing artificial muscles that can replace biological muscles to accomplish various tasks iswhat we have long been aiming for.Recent advances in flexible materials and 3D printing technology greatly promote the development of artificial muscle technology.A variety of flexible material-based artificial muscles that are driven by different external stimuli,including pressure,voltage,light,magnetism,temperature,etc.,have been developed.Among these,fluid-driven artificial muscles(FAMs),which can convert the power of fluid(gas or liquid)into the force output and displacement of flexible materials,are the most widely used actuation methods for industrial robots,medical instruments,and human-assisted devices due to their simplicity,excellent safety,large actuation force,high energy efficiency,and low cost.Herein,the bio-design,manufacturing,sensing,control,and applications of FAMs are introduced,including conventional pneumatic/hydraulic artificial muscles and several innovative artificial muscles driven by functional fluids.What’s more,the challenges and future directions of FAMs are discussed. 展开更多
关键词 Artificial muscles FLUID Bio-design MANUFACTURING Sensoring CONTROL
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Co-regulation of circadian clock genes and microRNAs in bone metabolism 被引量:5
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作者 Tingting LI Shihua ZHANG +3 位作者 Yuxuan YANG Lingli ZHANG Yu YUAN jun zou 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2022年第7期529-546,共18页
Mammalian bone is constantly metabolized from the embryonic stage,and the maintenance of bone health depends on the dynamic balance between bone resorption and bone formation,mediated by osteoclasts and osteoblasts.It... Mammalian bone is constantly metabolized from the embryonic stage,and the maintenance of bone health depends on the dynamic balance between bone resorption and bone formation,mediated by osteoclasts and osteoblasts.It is widely recognized that circadian clock genes can regulate bone metabolism.In recent years,the regulation of bone metabolism by non-coding RNAs has become a hotspot of research.MicroRNAs can participate in bone catabolism and anabolism by targeting key factors related to bone metabolism,including circadian clock genes.However,research in this field has been conducted only in recent years and the mechanisms involved are not yet well established.Recent studies have focused on how to target circadian clock genes to treat some diseases,such as autoimmune diseases,but few have focused on the co-regulation of circadian clock genes and microRNAs in bone metabolic diseases.Therefore,in this paper we review the progress of research on the co-regulation of bone metabolism by circadian clock genes and microRNAs,aiming to provide new ideas for the prevention and treatment of bone metabolic diseases such as osteoporosis. 展开更多
关键词 Circadian rhythm Circadian clock gene MICRORNAS Bone metabolism
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Coupled models of heat transfer and phase transformation for the run-out table in hot rolling 被引量:4
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作者 Shui-xuan CHEN jun zou Xin FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第7期932-939,共8页
Mathematical models are been proposed to simulate the thermal and metallurgical behaviors of the strip occtLrring on the run-out table (ROT) in a hot strip mill. A variational method is utilized for the discretizati... Mathematical models are been proposed to simulate the thermal and metallurgical behaviors of the strip occtLrring on the run-out table (ROT) in a hot strip mill. A variational method is utilized for the discretization of the governing transient conduction-convection equation, with heat transfer coefficients adaptively determined by the actual mill data. To consider the thermal effect of phase transformation during cooling, a constitutive equation for describing austenite decomposition kinetics of steel in air and water cooling zones is coupled with the heat transfer model. As the basic required inputs in the numerical simulations, thermal material properties are experimentally measured for three carbon steels and the least squares method is used to statistically derive regression models for the properties, including specific heat and thermal conductivity. The numerical simulation and experimental results show that the setup accuracy of the temperature prediction system of ROT is effectively improved. 展开更多
关键词 Run-out table (ROT) Cooling process Heat transfer Phase change Material properties
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Genome-wide prediction for hybrids between parents with distinguished difference on exotic introgressions in Brassica napus 被引量:4
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作者 Dandan Hu Yusheng Zhao +7 位作者 Jinxiong Shen Xiangxiang He Yikai Zhang Yong Jiang Rod Snowdon Jinling Meng Jochen C.Reif jun zou 《The Crop Journal》 SCIE CSCD 2021年第5期1169-1178,共10页
Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can s... Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can support pre-breeding in populations with exotic introgressions.We evaluated seed yield,seed yield related traits and seed quality traits of 363 hybrids of Brassica napus (AACC) derived from two parental populations divergent on massive exotic introgression of related species in three environments.The hybrids presented strong heterosis on seed yield,which was much higher than other investigated traits.Five genomic best linear unbiased prediction models considering the exotic introgression and different marker effects (additive,dominance,and epistatic effects) were constructed to test the prediction ability for different traits of the hybrids.The analysis showed that the trait complexity,exotic introgression,genetic relationship between the training set and testing set,training set size,and environments affected the prediction ability.The models with best prediction ability for different traits varied.However,relatively high prediction ability (e.g.,0.728 for seed yield) was also observed when the simplest models were used,excluding the effects of the special exotic introgression and epistasis effect by5-fold cross validation,which would simplify the prediction for the trait with complex architecture for hybrids with exotic introgression.The results provide novel insights and strategies for genome-wide prediction of hybrids between genetically distinct parent groups with exotic introgressions. 展开更多
关键词 Hybrid Genome-wide prediction Exotic introgression Brassica napus HETEROSIS
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Circular RNAs:typical biomarkers for bone-related diseases 被引量:4
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作者 Linghui HU Wei WU jun zou 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2022年第12期975-988,共14页
Bone is a connective tissue that has important functions in the human body.Cells and the extracellular matrix(ECM)are key components of bone and are closely related to bone-related diseases.However,the outcomes of con... Bone is a connective tissue that has important functions in the human body.Cells and the extracellular matrix(ECM)are key components of bone and are closely related to bone-related diseases.However,the outcomes of conventional treatments for bone-related diseases are not promising,and hence it is necessary to elucidate the exact regulatory mechanisms of bone-related diseases and identify novel biomarkers for diagnosis and therapy.Circular RNAs(circRNAs)are single-stranded RNAs that form closed circular structures without a 5’cap or 3’tail and polycyclic adenylate tails.Due to their high stability,circRNAs have the potential to be typical biomarkers.Accumulating evidence suggests that circRNAs are involved in bone-related diseases,including osteoarthritis,osteoporosis,osteosarcoma,multiple myeloma,intervertebral disc degeneration,and rheumatoid arthritis.Herein,we summarize the recent research progress on the characteristics and functions of circRNAs,and highlight the regulatory mechanism of circRNAs in bone-related diseases. 展开更多
关键词 Circular RNA Bone-related disease Competing endogenous RNA(ceRNA) MicroRNA
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Optimal design of Stewart platforms based on expanding the control bandwidth while considering the hydraulic system design 被引量:3
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作者 Wei WANG Hua-yong YANG +2 位作者 jun zou Xiao-dong RUAN Xin FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第1期22-30,共9页
We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart platform.The method is based on generalized natural frequency and takes hydraulic oil into consideration.A Lagran... We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart platform.The method is based on generalized natural frequency and takes hydraulic oil into consideration.A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass matrix.Using the model,the effect of leg inertia and the influence of design parameters on the generalized natural frequency are investigated.Finally,numerical examples are presented to validate and confirm the efficiency of the mathematical model.The results show that the leg inertia,especially the piston part plays an important role in the dynamics.The optimum diameter ratio of the base to the moving platform is between 2 and 3,and the optimum joint angle ratio of the base to the moving platform is about 1.The smaller joint angles and a longer leg stroke are favorable for raising system frequencies.The system oil should be preprocessed for large platforms with a requirement for good dynamic performance. 展开更多
关键词 Large Gough-Stewart platform Optimal design Control bandwidth Leg inertia Generalized natural frequency
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Precore mutation enhances viral replication to facilitate persistent infection especially in HBeAg-negative patients 被引量:3
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作者 Guixin Li Danli Yang +8 位作者 Xin Liu Ting Zhang Hui Liu jun zou Zimeng Xu Xiangmei Chen Lizhong Dai Hongsong Chen Fengmin Lu 《Virologica Sinica》 SCIE CAS CSCD 2024年第2期319-330,共12页
Naturally occurred precore(PC,G1896A)and/or basal core promoter(BCP,A1762T/G1764A)mutations are prevalent in chronic HBV-infected patients,especially those under HBeAg-negative status.However,the replicative capacity ... Naturally occurred precore(PC,G1896A)and/or basal core promoter(BCP,A1762T/G1764A)mutations are prevalent in chronic HBV-infected patients,especially those under HBeAg-negative status.However,the replicative capacity of HBV with PC/BCP mutations remains ambiguous.Herein,meta-analysis showed that,only under HBeAg-negative status,the serum HBV DNA load in patients with PC mutation was 7.41-fold higher than those without the mutation.Both PC mutation alone and BCPþPC mutations promoted HBV replication in cell and hydrodynamic injection mouse models.In human hepatocyte chimeric mouse model,BCPþPC mutations led to elevated replicative capacity and intrahepatic core protein accumulation.Mechanistically,preC RNA harboring PC mutation could serve as mRNA to express core and P proteins,and such pgRNA-like function favored the maintenance of cccDNA pool under HBeAg-negative status.Additionally,BCPþPC mutations induced more extensive and severe human hepatocyte damage as well as activated endoplasmic reticulum stress and TNF signaling pathway in livers of chimeric mice.This study indicates that HBeAg-negative patients should be monitored on HBV mutations regularly and are expected to receive early antiviral treatment to prevent disease progression. 展开更多
关键词 Hepatitis B virus Precore mutation Basal core promoter mutations Endoplasmic reticulum stress
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Squeal noise in hydraulic poppet valves 被引量:2
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作者 Da-yun YI Liang LU +1 位作者 jun zou Xin FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第4期317-324,共8页
The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying "squeal" noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of ... The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying "squeal" noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results. 展开更多
关键词 Poppet valve Squeal noise Helmholtz resonance Fluid acoustics Shear layer instability
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Adaptive robust control of soft bending actuators:an empirical nonlinear model-based approach 被引量:2
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作者 Cong CHEN jun zou 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2021年第9期681-694,共14页
Soft robotics,compared with their rigid counterparts,are able to adapt to uncharted environments,are superior in safe human-robot interactions,and have low cost,owing to the native compliance of the soft materials.How... Soft robotics,compared with their rigid counterparts,are able to adapt to uncharted environments,are superior in safe human-robot interactions,and have low cost,owing to the native compliance of the soft materials.However,customized complex structures,as well as the nonlinear and viscoelastic soft materials,pose a great challenge to accurate modeling and control of soft robotics,and impose restrictions on further applications.In this study,a unified modeling strategy is proposed to establish a complete dynamic model of the most widely used pneumatic soft bending actuator.First,a novel empirical nonlinear model with parametric and nonlinear uncertainties is identified to describe the nonlinear behaviors of pneumatic soft bending actuators.Second,an inner pressure dynamic model of a pneumatic soft bending actuator is established by introducing a modified valve flow rate model of the unbalanced pneumatic proportional valves.Third,an adaptive robust controller is designed using a backstepping method to handle and update the nonlinear and uncertain system.Finally,the experimental results of comparative trajectory tracking control indicate the validity of the proposed modeling and control method. 展开更多
关键词 Pneumatic soft bending actuator Empirical nonlinear model identification Unbalanced pneumatic proportional valve modeling Adaptive robust control Trajectory tracking
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The occurrence,inheritance,and segregation of complex genomic structural variation in synthetic Brassica napus 被引量:2
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作者 Dandan Hu Jin Lu +12 位作者 Wenwen Li Yinghui Yang junxiong Xu Han Qin Hao Wang Yan Niu Huaiqi Zhang Qingqing Liu Xiangxiang He Annaliese S.Mason JChris Pires Zhiyong Xiong jun zou 《The Crop Journal》 SCIE CSCD 2024年第2期515-528,共14页
"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic s... "Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding programs.Here,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome composition.We observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger SV.Surprisingly,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic lines.However,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for traits.Our results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation. 展开更多
关键词 ALLOPOLYPLOID Large Genome structural variation Linkage mapping Synthetic polyploids Inheritance and segregation
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