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Insufficient MIRO1 contributes to declined oocyte quality during reproductive aging

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Science China Life Sciences 2025年

作者： Zhen-Nan pan Hao-Lin Zhang Kun-Huan Zhang Jia-Qian Ju Jing-Cai Liu shao-Chen Sun College of Animal Science and Technology Nanjing Agricultural University Reproductive Medicine Centre The Affiliated Yantai Yuhuangding Hospital of Qingdao University

Mitochondrial Rho-GTPase 1 (MIRO1) is an outer mitochondrial membrane protein which regulates mitochondrial transport and mitophagy in mitosis. In present study, we reported the crucial roles of MIRO1 in mammalian oocyte meiosis and its potential relationship with aging. We found that MIRO1 expressed in mouse and porcine oocytes, and its expression decreased in aged mice. MIRO1 deficiency caused the failure of meiotic resumption and polar body extrusion in both mouse and porcine oocytes, which could be rescued by exogenous MIRO1supplementation. Mass spectrometry data indicated that MIRO1 associated with several cytoskeleton and cell cycle-related proteins, and MIRO1 regulated motor protein Dynein for microtubule-organizing centers (MTOCs) dynamics at germinal vesicle (GV) stage, which determined meiotic resumption. Furthermore, we found that MIRO1 regulated Aurora A and kinesin family member 11 (KIF11) for meiotic spindle assembly in oocytes. Besides, MIRO1 associated with several mitochondria-related proteins dynamic-related protein 1 (DRP1),Parkin and lysosomal-associated membrane protein 2 (LAMP2) for mitochondrial dynamics and mitophagy during oocyte meiosis. Taken together, our results suggested that MIRO1 played pivotal roles in meiotic resumption, spindle assembly and mitochondrial function in mouse and porcine oocytes, and its insufficiency might contribute to the oocyte maturation defects during aging.

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Dynamics of a prey-predator system under Poisson white noise excitation

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Acta Mechanica Sinica 2014年第5期30卷 739-745页

作者： shan-shan pan Wei-Qiu Zhu Department of Mechanics State Key Lab of Fluid Power Transmission and ControlZhejiang University

The classical Lotka-Volterra （LV） model is a well-known mathematical model for prey-predator ecosystems. In the present paper, the pulse-type version of stochastic LV model, in which the effect of a random natural environment has been modeled as Poisson white noise, is in- vestigated by using the stochastic averaging method. The averaged generalized It6 stochastic differential equation and Fokkerlanck-Kolmogorov （FPK） equation are derived for prey-predator ecosystem driven by Poisson white noise. Approximate stationary solution for the averaged generalized FPK equation is obtained by using the perturbation method. The effect of prey self-competition parameter e2s on ecosystem behavior is evaluated. The analytical result is confirmed by corresponding Monte Carlo （MC） simulation.

关键词： Prey-predator ecosystem Poisson white noise Stochastic averaging- Approximate stationary solution. Per turbation method

Responses of soil nitrogen, phosphorous and organic matter to vegetation succession on the Loess Plateau of China

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Journal of Arid Land 2015年第2期7卷 216-223页

作者： Man CHENG shao shan AN College of Natural Resources and Environment Northwest A&F University State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University

Revegetation is a traditional practice widely used for soil protection. We evaluated the effect of natural revegetation succession on soil chemical properties and carbon fractions （particulate organic carbon （POC）, humus carbon （HS-C）, humic acid carbon （HA-C） and fulvic acid carbon （FA-C）） on the Loess Plateau of China. The vegetation types, in order from the shortest to the longest enclosure duration, were：（a） abandoned overgrazed grassland （AbG3; 3 years）; （b） Hierochloe odorata Beauv. （HiO7; 7 years）; （c） Thymus mongoficus Ronnm （ThM15; 15 years）; （d） Artemisia sacrorum Ledeb （AtS25; 25 years）; （e） Stipa bungeana Trin Ledeb （StB36; 36 years） and （f） Stipa grandis P. Smirn （StG56; 56 years）. The results showed that the concentrations of soil organic carbon, total nitrogen and available phosphorus increased with the increase of restoration time except for ThM15. The concen- tration of NH4-N increased in the medium stage （for ThM15 and AtS25） and decreased in the later stage （for StB36 and StG56） of vegetation restoration. However, NO3-N concentration significantly increased in the later stage （for StB36 and StG56）. Carbon fractions had a similar increasing trend during natural vegetation restoration. The con- centrations of POC, HS-C, FA-C and HA-C accounted for 24.5%-49.1%, 10.6%-15.2%, 5.8%-9.1% and 4.6%-6.1% of total carbon, respectively. For AbG3, the relative changes of POC, HS-C and FA-C were significantly higher than that of total carbon during the process of revegetation restoration. The higher relative increases in POC, HS-C and FA-C confirmed that soil carbon induced by vegetation restoration was sequestrated by higher physical and chemical protection. The increases of soil C fractions could also result in higher ecological function in semiarid grassland ecosystems.

关键词： particulate organic carbon humus carbon humic acid carbon fulvic acid carbon carbon fraction natural vegetation succession

Geochronology and Geochemistry of Wangjiadashan Quartz Syenite Porphyry in Suizao Area of Hubei Province in the Tongbai-Dabie Orogenic Belt

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Journal of Earth Science 2023年第3期34卷 790-805页

作者： pan-pan Niu shao-Yong Jiang State Key Laboratory of Geological Processes and Mineral Resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of GeosciencesWuhan 430074China

The Wangjiadashan area in Suizhou-Zaoyang region of Hubei Province in the Tongbai-Dabie orogenic belt hosts important copper-gold deposits and contains a large number of quartz syenite porphyry dykes,occurring mostly along the NEE-trend *** this study,we used LA-ICP-MS zircon U-Pb dating method and obtained an age of 143.6±1.4 Ma,which represents the emplacement of these quartz syenite porphyry dykes was at the Yanshanian,but it was slightly earlier than the previously reported ages(139-135 Ma)for granites widespreading in Suizao *** geochemical data of the Wangjiadashan quartz syenite porphyry show high K_(2)O,CaO,Na_(2)O and Al_(2)O_(3)contents but extremely low MgO contents(0.01 wt.%-0.46 wt.%).The geochemical characteristics indicate that these quartz syenite porphyry dykes belong to the typical C-type adakite and were possibly formed in the post-collisional ***-isotopic(Sr-Nd-Pb-Hf)analyses indicate that these quartz syenite porphyry dykes were originated from crust without distinct mantle materials *** is suggested that the Wangjiadashan quartz syenite porphyry was generated from partial melting of the thickened lower continental crust,and garnet but no plagioclase was left as residual *** with the widespread granites of the Tongbai area,the Wangjiadashan quartz syenite porphyry formed earlier and derived from more juvenile and K-rich lower crust,while they all belong to intensive magmatism concentrated during the Early Cretaceous epoch in the Tongbai area.

关键词： quartz syenite porphyry zircon U-Pb dating geochemistry Sr-Nd-Pb-Hf isotopes petrogenesis Wangjiadashan Tongbai Orogen

Climate Change Risk Research: A Case Study on Flood Disaster Risk in China

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Advances in Climate Change Research 2012年第2期3卷 92-98页

作者： WU shao-Hong pan Tao HE shan-Feng Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Henan Polytechnic University Jiaozuo 454000 China

This paper discusses theories and methods of climate change risk studies for the research expansion in China. Climate change risks consist of three basic components including sensitivity, exposure, and possibility. Uncertainty, future events, damages, and relativity are the major features of climate change risk. Climate change risk research includes two key steps: risk assessment and risk management, the former is the process, and the latter is the ultimate goal which is the basis for actions to address climate change. We present the main framework and methods for climate change risk research. A case study on China's floods risk is taken as an example of climate change risk study. Finally, we point out main aspects of climate change risk research, including ensemble-based probabilistic projection, quantitative risk assessment, risk zoning and mapping, and risk management.

关键词： climate change risk assessment risk management uncertainty

Progress in helicopter infrared signature suppression

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Chinese Journal of Aeronautics 2014年第2期27卷 189-199页

作者： Zhang Jingzhou pan Chengxiong shan Yong Jiangsu Province Key Laboratory of Aerospace Power System College of Energy & Power Engineering Nanjing University of Aeronautics and Astronautics

Due to their low-attitude and relatively low-speed fight profiles, helicopters are subjected to serious threats from radio, infrared （IR）, visual, and aural detection and tracking. Among these threats, infrared detection and tracking are regarded as more crucial for the survivability of helicop- ters. In order to meet the requirements of infrared stealth, several different types of infrared sup- pressor （IRS） for helicopters have been developed. This paper reviews contemporary developments in this discipline, with particular emphasis on infrared signature suppression, advances in mixer-ejectors and prediction for helicopters. In addition, several remaining challenges, such as advanced IRS, emissivity optimization technique, helicopter infrared characterization, etc., are proposed, as an initial guide and stimulation for future research. In the future, the comprehen- sive infrared suppression in the 3-5 μm and 8-14 μm bands will doubtfully become the emphasis of helicopter stealth. Multidisciplinary optimization of a complete infrared suppression system deserves further investigation.

关键词： Helicopter Infrared radiation Infrared suppression Internal aerodynamics Mixer-ejector

Failure mechanism of full-size concrete filled steel circle and square tubes under uniaxial compression

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Science China(Technological Sciences) 2015年第10期58卷 1638-1647页

作者： CAI JingMing pan JinLong shan QiFeng Key Laboratory of Concrete and Pre-stressed Concrete Structures of Ministry of Education Southeast University

In this paper, the failure mechanisms of full-size concrete filled steel tubes(CFST) under uniaxial compression were investigated with nonlinear finite element method. Existing experimental results were employed to verify the validity of the finite element models of CFST specimens. Then, the numerical analysis was further conducted to study the mechanical behaviors of full-size CFST columns with circular and square cross sections under uniaxial compression. The simulation results indicate that the distribution of the contact pressure between circular steel tube and core concrete is much more uniform than that between square steel tube and concrete, resulting in much higher confinement and more efficient interaction between steel tube and core concrete in circular CFST columns, as well as ultimate load capacity and ultimate displacement. Extensive parametric analysis was also conducted to examine the effect of various parameters on the uniaxial compression behaviors of circular and square CFST columns.

关键词： CFST uniaxial compression finite element analysis interaction mechanism

Research Review of Principles and Methods for Ultrasonic Measurement of Axial Stress in Bolts

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 44-59页

作者： Qinxue pan Ruipeng pan Chang shao Meile Chang Xiaoyu Xu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of TechnologyBeijing 100081China

Bolts are important fasteners indispensable in the manufacturing field for their advantages, which include convenient assembly and disassembly, easy maintenance, refastenability to prevent looseness, and the avoidance of a phase change in the connected material composition. The precise control of the tightening force in bolts is closely related to the safety and reliability of the connected equipment or structure. Although there are many methods for estimating the tightening force applied to a bolt during assembly, poor accuracy in controlling the preload during the tightening process and a lack of monitoring to determine the residual axial force in service remain issues in evaluating the safety of bolted assemblies. As a nondestructive testing technology, ultrasonic measurement can be applied to successfully address these issues. In order to help researchers understand the theoretical basis and technological development in this field and to equip them to conduct further in-depth research, in this review, the basic knowledge describing the state of stress and deformation of bolts, as well as conventional testing methods are summarized and analyzed. Then, through a review of recent research of the ultrasonic measurement of the axial stress in bolts, the influence of the e ective stressed length and temperature are analyzed and proposed methods of calibration and compensation are reviewed. In order to avoid coupling errors caused by traditional piezoelectric transducers, two newly proposed ultrasonic coupling technologies, the electromagnetic acoustic transducer(EMAT) and the permanent mounted transducer system(PMTS), are reviewed. Finally, the new direction of research of the detection of residual axial stress in in-service bolts that have been assembled to yield is discussed.

关键词： Bolted connections Axial stress Ultrasonic waves Influencing factors Coupling techniques

Functional characterization of the catalytic and bromodomain of FgGCN5 in development,DON production and virulence of Fusarium graminearum

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Journal of Integrative Agriculture 2020年第10期19卷 2477-2487页

作者： WANG Qian-nan HUANG pan-pan ZHOU shan-yue The Key Lab of Integrated Crop Pests Management of shandong Province/College of Plant Health and Medicine Qingdao Agricultural UniversityQingdao 266109P.R.China

FgGCN5,a GCN5 homolog in Fusarium graminearum,plays a critical role in hyphal vegetative growth,asexual and sexual reproduction,deoxynivalenol(DON)biosynthesis and plant *** nuclear localized GCN5,four conserved sequence motifs(I-IV)are presented in the catalytic domain and a bromodomain in the *** a lysine acetyltransferase,conserved negatively charged residues are present to neutralize the protons from lysine ***,the role of conserved motifs/domains and residues in FgGCN5 are ***,we generated deletion mutant strains for each the conserved motifs/domains and a glutamate residue 130(E130)replacement *** of each conserved motif in the catalytic domain and replacement of E130 site resulted in manifold defects in hyphae growth,asexual and sexual development,DON biosynthesis,and plant *** defects in the mutant strains were similar to deletion *** deletion of the bromodomain led a significant reduction in DON production and virulence,with no effects on hyphae growth,asexual or sexual ***5 was further found to localize to the nucleus in conidia and hyphae *** conclusion,FgGCN5 encodes a nuclear localized *** conserved motifs in the catalytic domain and E130 are essential for correct functions of the *** conserved bromodomain is impotant for DON production and pathogen *** was the first report to identify the functions of conserved motifs/domains in FgGCN5,which will contribute to our understanding of the mechanism(s)by which FgGCN5 regulates ***.

关键词： FgGCN5 catalytic domain bromodomain DON virulence