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The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi li Jing Xue Yuejia ma Ke ye Xue Zhao Fangliang Ge Feifei Zheng Lulu liu Xu Gao Dayong Wang qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

Study on Properties of Ti(C,N)/TiN Multi-Element-layer Films Plus Nanometer Lubrication Dry Films

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材料热处理学报 2004年第05B期25卷 909-912页

作者： HUANGYuan-lin mashi-ning lichang-qing ZHUYou-li StateKeyLaboratoryforRemanufacturing Beijing100072China

Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD analysis show that the main composition of the composite films system were Ti(C,N), TiN, Al3Ti, Al and a little Ti2N. The presence of MjTi new phase in the interface of the films/substrates indicated some metallurgical bonding between them, which implies higher adhesive strength of the films/substrates system. Pin-on-disc tests showed that the wear resistance of the substrates was improved substantially. However, the coefficient of friction of the films/substrate system was high (u=0.66), which resulted in the wear of the counterparts. To reduce the coefficient of friction, nanometer lubrication dry films was applied on top of the multi-element-layer films to form composite films system and subsequent wear tests showed that the resulting composite films led to reduction of the coefficient of friction from 0.66 to 0.16. Meanwhile, wear mass loss of the counterpart was reduced from 1.29 mg to 0.02 mg, so that increased wear resistance and reduced friction effects were achieved.

关键词：多电弧离子电镀法铝合金摩擦学纳米薄膜

A nonparametric spectrum estimation method for dispersion and attenuation analysis of borehole acoustic measurements

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Petroleum Science 2023年第1期20卷 241-248页

作者： Bing Wang Wei li qing ye Kun-Yu ma State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Beijing Research Center Aramco AsiaBeijing100102China

Dispersion and attenuation analysis can be used to determine formation anisotropy induced by fractures,or *** this paper,we propose a nonparametric spectrum estimation method to get phase dispersion characteristics and attenuation *** designing an appropriate vector filter,phase velocity,attenuation coefficient and amplitude can be inverted from the waveform recorded by the receiver *** analysis of this algorithm is compared with Extended Prony Method(EPM)and Forward and Backward matrix Pencil(FBMP)*** on the analysis results,the proposed method is capable of achieving high resolution and precision as the parametric spectrum estimation *** the meantime,it also keeps high stability as the other nonparametric spectrum estimation *** last,applications to synthetic waveforms modeled using finite difference method and real data show its *** real data processing results show that the P-wave attenuation log is more sensitive to oil formation compared to S-wave;and the S-wave attenuation log is more sensitive to shale formation compared to P-wave.

关键词： Dispersion analysis Attenuation factor Nonparametric spectrum estimation method Acoustic logging Fluid type evaluation

等离子喷涂纳米结构n-Al_2O_3/Ni涂层性能研究

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金属热处理 2005年第7期30卷 70-74页

作者：李长青马世宁叶雄林装甲兵工程学院再制造工程系北京100072

采用化学方法在纳米Al2O3颗粒表面包覆了一层Ni,通过喷雾干燥法制成了纳米结构热喷涂喂料。采用等离子喷涂工艺在45钢试样上制备了纳米结构nAl2O3/Ni涂层,并对涂层的性能和结构进行了试验分析。结果表明,粒子飞行过程中存在“爆破”及... 详细信息

采用化学方法在纳米Al2O3颗粒表面包覆了一层Ni,通过喷雾干燥法制成了纳米结构热喷涂喂料。采用等离子喷涂工艺在45钢试样上制备了纳米结构nAl2O3/Ni涂层,并对涂层的性能和结构进行了试验分析。结果表明,粒子飞行过程中存在“爆破”及物质迁移现象;涂层结构疏松多孔,与基体平均结合强度低;喷涂过程发生了由αAl2O3向γAl2O3的转变;与电弧喷涂类似3Cr13钢成分涂层相比,nAl2O3/Ni涂层耐磨性显著提高,摩擦系数降低,主要的磨损形式是伴随疲劳磨损的粘着磨损。

关键词：等离子喷涂涂层纳水结构喂料性能

The damage to model concrete gravity dams subjected to water explosions

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Defence Technology（防务技术） 2023年第9期27卷 119-137页

作者： Shang ma ye-qing Chen Zhen-qing Wang Shu-tao li qing Zhu Long-ming Chen College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China Institute of Defense Engineering AMSPLABeijing100036China

Over the past century,the safety of dams has gradually attracted attention from all *** on the dynamic response and damage evolution of dams under extreme loads is the basis of dam safety *** recent decades,scholars have studied the responses of dams under earthquake loads,but there is still much room for improvement in experimental and theoretical research on small probability loads such as *** this paper,a 50-m-high concrete gravity dam is used as a prototype dam,and a water explosion model test of a 2.5-m-high concrete gravity dam is *** water pressure and the acceleration response of the dam body in the test are *** pressure characteristics and dynamic response of the dam body are *** the dam damage test as an example,a numerical model of concrete gravity dam damage is established,and the damage evolution of the dam body is *** combining experiments and numerical simulations,the damage characteristics of the dam body under the action of different charge water explosions are *** integrity of the dam body is well maintained under the action of a small-quantity water explosion,and the dynamic response of the dam body is mainly caused by the shock *** the shock wave and the bubble pulsation cause the dam body to accelerate,and the peak acceleration of the dam body under the action of the bubble pulsation is only one percent of the peak acceleration of the dam body under the action of the shock *** subjected to explosions in large quantities of water,the dam body is seriously *** the action of a shock wave,the dam body produces a secondary acceleration response,which is generated by an internal interaction after the dam body is *** damage evolution process of the dam body under the action of a large-scale water explosion is analysed,and it is found that the shock wave pressure of the water explosion causes local damage to the dam body facing the ***

关键词： Underwater explosion Concrete gravity dam Model test Damage evolution

Spontaneous resolution of idiopathic intestinal obstruction after pneumonia: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4512-4520页

作者： Bing-qing Zhang Xiao-Yan Dai Qiu-Yue ye Long chang Zhi-Wei Wang Xiao-qing li Yong-ning li Internal Medicine Peking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China International Medical Services Peking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Interventional Section Department of RadiologyPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Neurosurgery Peking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China

BACKGROUND Duodenal obstruction is a common clinical scenario that can either be mechanical or a *** management of intestinal obstruction starts from localization and proceeds to histological examination of the stenotic *** factors and dysfunction of distant organs might contribute to the development of intestinal ***,we report a unique case of idiopathic mechanical duodenal obstruction,which resolved spontaneously after 3 mo of conservative treatment,but was followed by intestinal *** SUMmaRY An 84-year-old woman presented with worsened postprandial vomiting accompanied by prolonged *** noninvasive investigations revealed complete circumferential stenosis in the descending duodenum without known *** surgery was postponed due to septic shock and possible pulmonary fungal *** treatment for 3 mo for ileus and control of pulmonary infection resolved the intestinal obstruction ***,2 wk later,she had regurgitation and postprandial vomiting again,complicated by deteriorating wheezing and *** tomography revealed a dilated stomach and proximal duodenum without new intestinal stricture or pulmonary *** patient fully recovered after combined treatment with antireflux agents,enema,prokinetics,and *** This complicated case highlights the inter-relationship of local and systemic contributions to ileus and gut dysfunction,which requires multidisciplinary treatment.

关键词： Duodenal obstruction Pseudo-intestinal obstruction Pneumonia Airway hyperresponsiveness Multidisciplinary treatment Case report

Towards an Accurate and Robust Roe-Type Scheme for All mach Number Flows

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Advances in Applied mathematics and Mechanics 2019年第1期11卷 132-167页

作者： Wenjia Xie ye Zhang qing chang Hua li College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073HunanChina

We propose an accurate and robust Roe-type scheme applied to the compressible Euler system at all mach *** study the occurrence of unstable modes during the shock wave computation,a shock instability analysis of several Roe-type schemes is carried *** analysis approach allows to propose a simple and effective modification to eliminate shock instability of the Roe method for hypersonic flows.A desirable feature of this modification is that it does not resort to any additional numerical dissipation on linear degenerate waves to suppress the shock *** an all mach correction strategy,the modified Roe-type scheme is further extended to solve flow problems at all mach *** results that are obtained for various test cases indicate that the new scheme has a good performance in terms of accuracy and robustness.

关键词： Roe scheme low mach number numerical shock instability

Effect of resveratrol on pancreatic oxygen free radicals in rats with severe acute pancreatitis

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World Journal of Gastroenterology 2006年第1期12卷 137-140页

作者： Zhen-Dong li qing-Yong ma chang-An Wang Department of HepatobiliarySurgery First Hospital of Xi'an Jiaotong University Xi'an710061 Shaanxi Province China Department of Pathology Xi'an MunicipalCenter Hospital Xi'an 710068 Shaanxi Province China

AIM： To investigate the therapeutic effects of resveratrol （RESV） as a free radical scavenger on experimental severe acute pancreatitis （SAP）. METHODS： Seventy-two male Sprague-Dawley rats were divided randomly into sham operation group, SAP group, and resveratrol-treated group. Pancreatitis was induced by intraductal administration of 0.1 mL/kg 4% sodium taurocholate. RESV was given intravenously at a dose of 20 mg/kg body weight. All animals were killed at 3, 6, 12 h after induction of the model. Serum amylase, pancreatic superoxide dismutase （SOD）, malondialdehyde （MDA）, and myeloperoxidase （MPO） were determined. Pathologic changes of the pancreas were observed under optical microscope. RESULTS： The serum amylase, pancreatic MPO and the score of pathologic damage increased after the induction of pancreatitis, early （3, 6 h） SAP samples were characterized by decreased pancreatic SOD and increased pancreatic MDA. Resveratrol exhibited a protective effect against lipid peroxidation in cell membrane caused by oxygen free radicals in the early stage of SAP. This attenuation of the redox state impairment reduced cellular oxidative damage, as reflected by lower serum amylase, less severe pancreatic lesions, normal pancreatic MDA levels, as well as diminished neutrophil infiltration in pancreas. CONCLUSION： RESV may exert its therapeutic effect on SAP by lowering pancreatic oxidative free radicals and reducing pancreatic tissue infiltration of neutrophils.

关键词： Severe acute pancreatitis Resveratrol Oxygen free radical Neutrophil

Modulating Effects of Chlorogenic Acid on lipids and Glucose Metabolism and Expression of Hepatic Peroxisome Proliferator-activated Receptor-α in Golden Hamsters Fed on High Fat Diet

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Biomedical and Environmental Sciences 2009年第2期22卷 122-129页

作者： SHU-YUAN li CuI-qing chang FU-YING ma AND chang-LONG YU Division of Nutrition and Biochemistry Institute of Sports Medicine Third Hospital Peking University Beijing 100191 China Department of Pediatrics General Hospital of Chinese People's Armed Police Forces Beijing 100039 China

Objective To examine the effects of chlorogenic acid （CGA） on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-α （PPAR-α） in these effects. Methods Twenty male golden hamsters were randomly divided into CGA treatment group （n=10, given peritoneal injection of CGA solution prepared with PBS, 80 mg CGA/kg body weight daily）, and control group （n=10, given PBS i.p. at the average volume of the treatment group）. Animals in both groups were given 15% high fat diet. Eight weeks after treatment with CGA, the level of biochemical parameters in fasting serum and tissues and the expression of hepatic mRNA and protein PPAR-α were determined. Results Eight weeks after treatment with CGA, the levels of fasting serum triglyceride （TG）, free fatty acid （FFA）, total cholesterol （TC）, low density lipoprotein cholesterol （LDL-C）, high density lipoprotein cholesterol （HDL-C）, glucose （FSG）, and insulin （FSI） were significantly lower in the GGA treatment group than in the control group. CGA also led to higher activity of hepatic lipase （HL） lower contents of TG and FFA in liver, and lower activity of lipoprotein lipase （LPL） in skeletal muscle. Furthermore, CGA significantly elevated significantly elevated the expression level of mRNA and protein expression in hepatic PPAR-α. Conclusion CGA can modify lipids and glucose metabolism, which may be attributed to PPAR-α facilitated lipid clearance in liver and improved insulin sensitivity.

关键词： Chlorogenic acid Golden hamster High fat diet Hypolipidemic effect Hypoglycemic effect lipids clearance FFA drainage PPAR-α Insulin sensitivity