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White-Sutton综合征临床表型扩展及治疗尝试:病例系列报告
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作者 范瑞 张一宁 +9 位作者 李辛 李娟 李群 李智颖 顾世立 胡斐涵 高诗阳 冯碧云 姚如恩 王秀敏 《临床儿科杂志》 北大核心 2026年第1期38-43,共6页
目的 White-Sutton综合征(WHSUS)是一种表型差异极大的单基因遗传病,本研究旨在进一步扩展WHSUS的临床表型谱,并探讨潜在改善症状的治疗方法。方法 回顾性分析2018年7月至2023年2月就诊于上海儿童医学中心的4例WHSUS患儿的临床资料。结... 目的 White-Sutton综合征(WHSUS)是一种表型差异极大的单基因遗传病,本研究旨在进一步扩展WHSUS的临床表型谱,并探讨潜在改善症状的治疗方法。方法 回顾性分析2018年7月至2023年2月就诊于上海儿童医学中心的4例WHSUS患儿的临床资料。结果 4例患儿首诊年龄范围为1~9岁,男2例、女2例,均有语言及运动发育落后。例1,女,表现为既往未报道过的临床表型,即脊髓栓系综合征(TCS),同时患有胰岛素抵抗。例2,女,因身材矮小和学习成绩差就诊,患儿接受了3.5年的生长激素治疗,随访至12岁1个月时,身高为152 cm(P50),月经正常。例3,男,因语言发育迟缓就诊。例4,男,语言发育迟缓且有孤独症谱系障碍倾向。此4例均存在POGZ基因新生变异,诊断为WHSUS。结论 本研究详细报道了4例WHSUS患者的临床特征,扩展了WHSUS的表型谱。同时,首次报道了WHSUS伴身材矮小患儿应用生长激素的治疗尝试,为此类疾病的对症治疗提供了新的思路。 展开更多
关键词 white-Sutton综合征 POGZ基因 脊髓栓系综合征
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NLRP3 inflammasome and gut microbiota–brain axis:A new perspective on white matter injury after intracerebral hemorrhage 被引量:1
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作者 Xiaoxi Cai Xinhong Cai +4 位作者 Quanhua Xie Xueqi Xiao Tong Li Tian Zhou Haitao Sun 《Neural Regeneration Research》 2026年第1期62-80,共19页
Intracerebral hemorrhage is the most dangerous subtype of stroke,characterized by high mortality and morbidity rates,and frequently leads to significant secondary white matter injury.In recent decades,studies have rev... Intracerebral hemorrhage is the most dangerous subtype of stroke,characterized by high mortality and morbidity rates,and frequently leads to significant secondary white matter injury.In recent decades,studies have revealed that gut microbiota can communicate bidirectionally with the brain through the gut microbiota–brain axis.This axis indicates that gut microbiota is closely related to the development and prognosis of intracerebral hemorrhage and its associated secondary white matter injury.The NACHT,LRR,and pyrin domain-containing protein 3(NLRP3)inflammasome plays a crucial role in this context.This review summarizes the dysbiosis of gut microbiota following intracerebral hemorrhage and explores the mechanisms by which this imbalance may promote the activation of the NLRP3 inflammasome.These mechanisms include metabolic pathways(involving short-chain fatty acids,lipopolysaccharides,lactic acid,bile acids,trimethylamine-N-oxide,and tryptophan),neural pathways(such as the vagus nerve and sympathetic nerve),and immune pathways(involving microglia and T cells).We then discuss the relationship between the activated NLRP3 inflammasome and secondary white matter injury after intracerebral hemorrhage.The activation of the NLRP3 inflammasome can exacerbate secondary white matter injury by disrupting the blood–brain barrier,inducing neuroinflammation,and interfering with nerve regeneration.Finally,we outline potential treatment strategies for intracerebral hemorrhage and its secondary white matter injury.Our review highlights the critical role of the gut microbiota–brain axis and the NLRP3 inflammasome in white matter injury following intracerebral hemorrhage,paving the way for exploring potential therapeutic approaches. 展开更多
关键词 gut microbiota gut microbiota–brain axis immune intracerebral hemorrhage NEUROINFLAMMATION NLRP3 protein stroke THERAPEUTICS white matter injury
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Prolonged consumption of white beer increases levels of short-chain fatty acids and Prevotellaceae bacteria in mice
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作者 Zhaoxi Liu Yongheng Rong +5 位作者 Shuxia Huang Hua Yin Lushan Wang Shumin Hu Junhong Yu Min Chen 《Food Science and Human Wellness》 2026年第1期67-79,共13页
Beer is a prominent fermented food product and is regarded as the one of most widely consumed beverage globally.There is a dearth of studies examining the impact of different types of beer with intricate components as... Beer is a prominent fermented food product and is regarded as the one of most widely consumed beverage globally.There is a dearth of studies examining the impact of different types of beer with intricate components as a comprehensive intervention on human health and immune status.This study used a 14-day continuous drinking intervention consisting of 5 beers,namely white beer,India pale ale(IPA),Pilsner,non-alcoholic beer,and premium lager beer.Surprisingly,our findings indicate that consuming white beer has little impact on the gut microbiota and physiological condition of mice,whereas consuming other types of beer leads to an increase in Lactobacillus and a decrease in Lachnospiraceae.In addition,we devised an extended feeding experiment to investigate the comparative safety and health benefits of consuming white beer.The research showed that when mice drank excessive quantities of white beer over 42 days,the intestines of the mice had more Prevotellaceae and the Firmicutes to Bacteroidetes ratio(F/B ratio)had a decline from 1.29 to 0.38.The levels of acetic acid,propionic acid,and isobutyric acid increased from 1.0,0.27,and 0.015 mg/g to 1.28,0.38,and 0.037 mg/g,respectively(P<0.05).There were no significant changes observed in the levels of most measured cytokines in the colon tissue of mice that consumed beer,however,there was an increase in the concentration of the inflammatory factor tumor nesrosis factor-α(TNF-α)from 135.86 pg/mL in the control group to 189.78 pg/mL in the white beer group(P<0.01).These results give us real-world proof that we can use to study how different beers affect the host’s health and satisfaction in future research. 展开更多
关键词 Gut microbiota BEER CYTOKINE Short-chain fatty acids white beer Prevotellaceae
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White matter matters inβ-glucocerebrosidase-related pathologies
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作者 Loris Russo Matilde Cescon 《Neural Regeneration Research》 2026年第6期2333-2334,共2页
β-glucocerebrosidase in health and disease:Mutations in theβ-glucocerebrosidase(GBA)gene do cause the rare lysosomal storage disorder Gaucher’s disease(GD)with an estimated global prevalence of 1:200,000(Imbalzano ... β-glucocerebrosidase in health and disease:Mutations in theβ-glucocerebrosidase(GBA)gene do cause the rare lysosomal storage disorder Gaucher’s disease(GD)with an estimated global prevalence of 1:200,000(Imbalzano et al.,2024).GBA is a membrane-bound lysosomalenzyme responsible for glucosylceramide and glucosylsphingosine hydrolysis.When this enzyme is mutated and dysfunctional,its substrates progressively accumulate within cells. 展开更多
关键词 white matter GLUCOSYLCERAMIDE Gaucher s disease GLUCOCEREBROSIDASE glucosylsphingosine lysosomal storage disorder glucocerebrosidase gene
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Delayed microglial depletion protects against white matter injury following neonatal cerebral hemorrhage in mice
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作者 Xiaoxiao Jing Xiaoli Zhang +13 位作者 Hongwei Li Yu Yang Zuhang Zhao Yuandan Li Jinjin Zhu Yiran Xu Jing Yuan Tiantian He Chen Zhang Juan Song Xin Zhao Xiaoyang Wang Changlian Zhu Falin Xu 《Neural Regeneration Research》 2026年第6期2621-2631,共11页
Germinal matrix hemorrhage in preterm neonates often leads to white matter injury,contributing to long-term neurodevelopmental impairments.As resident brain immune cells,microglia play a complex role in injury respons... Germinal matrix hemorrhage in preterm neonates often leads to white matter injury,contributing to long-term neurodevelopmental impairments.As resident brain immune cells,microglia play a complex role in injury response,including inflammation and repair.Although colony-stimulating factor 1 receptor inhibitors such as PLX5622 enable the selective depletion of microglia,their therapeutic potential in neonatal germinal matrix hemorrhage remains underexplored.Here,we used a collagenase-induced germinal matrix hemorrhage model in postnatal day 5 mice,and intraperitoneally administered PLX562272 hours post-germinal matrix hemorrhage to achieve targeted,temporary microglial depletion during the peak injury response.We then assessed the effects of this delayed intervention on oligodendrocyte lineage cell maturation,white matter integrity,and neurobehavioral outcomes.Additionally,RNA sequencing data from a germinal matrix hemorrhage rat model were analyzed using weighted gene co-expression network analysis to identify the critical phases for interventions.RNA sequencing data revealed a critical period in which key synaptic functions declined while immune responses intensified post-germinal matrix hemorrhage,thus pinpointing the critical response phases for potential interventions.Delayed PLX5622 treatment effectively depleted activated microglia,protecting against white matter injury and enhancing oligodendrocyte lineage cell maturation and myelination in subcortical white matter regions.Moreover,magnetic resonance imaging analysis revealed reduced brain lesion volumes in treated mice.Behaviorally,PLX5622-treated mice exhibited significant improvements in motor coordination and reduced hyperactivity compared with vehicle-treated germinal matrix hemorrhage model mice.These findings suggest that,when timed to avoid interference with initial oligodendrocyte lineage cell proliferation,targeted microglial depletion with PLX5622 significantly mitigates white matter damage and improves neurobehavioral outcomes in neonatal germinal matrix hemorrhage.The present study highlights the therapeutic potential of selectively modulating microglial reactivity to support neurodevelopment in preterm infants with brain injury. 展开更多
关键词 colony-stimulating factor 1 receptor germinal matrix hemorrhage microglia MYELINATION neonatal brain oligodendrocyte lineage cell PLX5622 white matter injury
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Physical exercise promotes white matter repair after ischemic stroke
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作者 Yating Mu Xiaofeng Yang +8 位作者 Yifeng Feng Liying Zhang Jinghui Xu Mingyue Li Rui Wu Shiying Li Xiaofei He Zejie Zuo Xiquan Hu 《Neural Regeneration Research》 2026年第6期2397-2406,共10页
White matter injury is a key factor impacting stroke recovery.Physical exercise can promote white matter repair.Immune cells,especially regulatory T(Treg)cells,contribute to strengthening white matter integrity,yet li... White matter injury is a key factor impacting stroke recovery.Physical exercise can promote white matter repair.Immune cells,especially regulatory T(Treg)cells,contribute to strengthening white matter integrity,yet little is known about the underlying mechanism.To examine this,we established a transient middle cerebral artery occlusion male mouse model.We found that physical exercise elevated brain Treg cells,thereby enhancing neurological recovery,reducing neuroinflammation,promoting myelin debris clearance,and accelerating white matter repair.Depletion of Treg cells caused a decrease in these positive effects of physical exercise.Mechanistically,the rise in osteopontin triggered by physical exercise is dampened when Treg cells are depleted.In addition,Treg-conditioned medium reduced oxygen-glucose deprivation/re-oxygenation-induced microglial inflammation and enhanced phagocytosis,which could be blocked by osteopontin antibodies.Importantly,although Treg infusion could mimic the protective effects of physical exercise,osteopontin blockade partially countered the effects of physical exercise and Treg cells.Finally,our sequencing data revealed a marked upregulation of C-X-C motif chemokine ligand 12(CXCL12)mRNA expression subsequent to physical exercise,which was confirmed at the protein level.Stimulation of Treg cells with stroke brain lysates increased C-X-C motif chemokine receptor 4(CXCR4)expression,indicating a potential role for the CXCL12-CXCR4 axis in recruiting Treg cells.These findings suggest that physical exercise promotes white matter repair after ischemic stroke by Treg cells. 展开更多
关键词 CXCL12 ischemic stroke MICROGLIA NEUROINFLAMMATION OSTEOPONTIN PHAGOCYTOSIS physical exercise transient middle cerebral artery occlusion Treg cells white matter injury
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Data-driven early warning of Gaussian white noise-induced critical transitions
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作者 Ruifang WANG Minhe JIA +2 位作者 Xuanqi FAN Jinzhong MA Yong XU 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期389-400,共12页
Many complex systems are frequently subject to the influence of uncertain disturbances,which can exert a profound effect on the critical transitions(CTs),potentially resulting in catastrophic consequences.Consequently... Many complex systems are frequently subject to the influence of uncertain disturbances,which can exert a profound effect on the critical transitions(CTs),potentially resulting in catastrophic consequences.Consequently,it is of uttermost importance to provide warnings for noise-induced CTs in various applications.Although capturing certain generic symptoms of transition behaviors from observational and simulated data poses a challenging problem,this work attempts to extract information regarding CTs from simulated data of a Gaussian white noise-induced tri-stable system.Using the extended dynamic mode decomposition(EDMD)algorithm,we initially obtain finite-dimensional approximations of both the stochastic Koopman operator and the generator.Subsequently,the drift parameters and the noise intensity within the system are identified from the simulated data.Utilizing the identified system,the parameter-dependent basin of the unsafe regime(PDBUR)is quantified,enabling data-driven early warning of Gaussian white noise-induced CTs.Finally,an error analysis is carried out to verify the effectiveness of the data-driven results.Our findings may serve as a paradigm for understanding and predicting noise-induced CTs in complex systems based on data. 展开更多
关键词 Gaussian white noise critical transition(CT) extended dynamic mode decomposition(EDMD) parameter-dependent basin of the unsafe regime(PDBUR)
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Improving recovery from traumatic spinal cord injury:Targeting remyelination versus white matter remodeling
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作者 Bethany R.Kondiles Wolfram Tetzlaff 《Neural Regeneration Research》 2026年第6期2337-2338,共2页
The inter-related pathological cascades following a traumatic spinal cord injury(tSCI)disrupt multiple cell types and physiological processes.Subsequently,motor and sensory functions are disrupted by breakdowns in cel... The inter-related pathological cascades following a traumatic spinal cord injury(tSCI)disrupt multiple cell types and physiological processes.Subsequently,motor and sensory functions are disrupted by breakdowns in cellular interactions and circuitry.Therapeutic interventions seek to modify some aspects of the injury course to enable the re-establishment of functional circuitry.Interventions often target one cell type(e.g.,promoting neuroprotection or neural regeneration)or one process(e.g.,modulating inflammation,affecting astrocytic,microglial,or macrophage responses.)Many axons in the spinal cord are myelinated,and after injury oligodendrocyte death causes demyelination.Promoting remyelination of spared or new axons to re-establish conduction seems a logical choice as a therapeutic target. 展开更多
关键词 traumatic spinal cord injury traumatic spinal cord injury tsci disrupt oligodendrocyte death REMYELINATION white matter remodeling neural regeneration modify some aspects injury course NEUROPROTECTION
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Lnc_011797 promotes ferroptosis and aggravates white matter lesions
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作者 Xiang Xu Yu Sun +5 位作者 Xiaoyan Zhu Shiyin Ma Jin Wei Chang He Jing Chen Xudong Pan 《Neural Regeneration Research》 2026年第5期2021-2030,共10页
Recent evidence suggests that ferroptosis plays a crucial role in the occurrence and development of white matter lesions.However,the mechanisms and regulatory pathways involved in ferroptosis within white matter lesio... Recent evidence suggests that ferroptosis plays a crucial role in the occurrence and development of white matter lesions.However,the mechanisms and regulatory pathways involved in ferroptosis within white matter lesions remain unclear.Long non-coding RNAs(lnc RNAs)have been shown to influence the occurrence and development of these lesions.We previously identified lnc_011797 as a biomarker of white matter lesions by high-throughput sequencing.To investigate the mechanism by which lnc_011797 regulates white matter lesions,we established subjected human umbilical vein endothelial cells to oxygenglucose deprivation to simulate conditions associated with white matter lesions.The cells were transfected with lnc_011797 overexpression or knockdown lentiviruses.Our findings indicate that lnc_011797 promoted ferroptosis in these cells,leading to the formation of white matter lesions.Furthermore,lnc_011797 functioned as a competitive endogenous RNA(ce RNA)for mi R-193b-3p,thereby regulating the expression of WNK1 and its downstream ferroptosis-related proteins.To validate the role of lnc_011797 in vivo,we established a mouse model of white matter lesions through bilateral common carotid artery stenosis.The results from this model confirmed that lnc_011797 regulates ferroptosis via WNK1 and promotes the development of white matter lesions.These findings clarify the mechanism by which lnc RNAs regulate white matter lesions,providing a new target for the diagnosis and treatment of white matter lesions. 展开更多
关键词 bilateral common carotid artery stenosis competing endogenous RNA EXOSOME ferroptosis human umbilical vein endothelial cells long non-coding RNAs miR-193b-3p oxygen-glucose deprivation white matter lesions WNK1
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Detection of white matter microstructural changes in patients with systemic lupus erythematosus based on multiple diffusion models and related diffusion metrics
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作者 Zhenxing Li Huanhuan Li +5 位作者 Bailing Tian Huiyang Liu Yueluan Jiang Pingting Yang Guoguang Fan Hu Liu 《Neural Regeneration Research》 2026年第6期2467-2474,共8页
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle... Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms. 展开更多
关键词 diffusion kurtosis imaging diffusion tensor imaging mean apparent propagator neurite orientation dispersion and density imaging neuropsychiatric systemic lupus erythematosus return to axis probability return to origin probability superior longitudinal fasciculus-3 superior thalamic radiation tract-based spatial statistics white matter microstructure
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基于矩匹配的Hull-White模型下商期权定价 被引量:3
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作者 张立东 吴水苗 +2 位作者 田静禾 董懿琳 孟祥波 《山东大学学报(理学版)》 北大核心 2025年第3期1-11,共11页
假设标的资产价格服从均值回复过程,运用矩匹配技术,研究Hull-White模型下商期权定价问题。相比于使用蒙特卡罗模拟方法,对Hull-White模型采用矩匹配的估值方法,可以在确保精度的基础上显著提升商期权定价的稳定性和效率。最后,在中国... 假设标的资产价格服从均值回复过程,运用矩匹配技术,研究Hull-White模型下商期权定价问题。相比于使用蒙特卡罗模拟方法,对Hull-White模型采用矩匹配的估值方法,可以在确保精度的基础上显著提升商期权定价的稳定性和效率。最后,在中国股票市场上,选取2个行业龙头公司的股票作为研究对象进行实例应用,评估期权定价模型在金融市场的适用性。结果显示,本模型与蒙特卡洛模拟方法的估计结果差异极小,但前者用时显著缩短。 展开更多
关键词 商期权 均值回复过程 HULL-white模型 矩匹配
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White Rabbit技术研究进展
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作者 齐苗苗 王剑 +1 位作者 林平卫 梁坤 《电子测量与仪器学报》 北大核心 2025年第6期1-10,共10页
光纤时频同步技术的需求逐渐向远距离、多节点、高精度的方向发展。白兔(WR)技术作为光纤时频传递的重要实现方案,在精确时间协议(PTP)的基础上进行了创新性扩展,通过引入同步以太网和数字双混频时差测量(DDMTD)技术,实现了主、从时钟... 光纤时频同步技术的需求逐渐向远距离、多节点、高精度的方向发展。白兔(WR)技术作为光纤时频传递的重要实现方案,在精确时间协议(PTP)的基础上进行了创新性扩展,通过引入同步以太网和数字双混频时差测量(DDMTD)技术,实现了主、从时钟之间亚纳秒级的时间偏差和纳秒量级的同步不确定度,更在标准化、通用化以及便捷组网等方面展现出显著优势。系统性阐述了WR技术的同步原理及其性能优势,深入分析了影响系统同步性能的关键因素,并对现有研究方法的优缺点进行了对比,最后进一步探讨了该技术当前面临的技术挑战与未来发展方向。研究表明,WR技术在分布式系统中具有广阔的应用前景,但要满足多样化应用场景的需求,仍需在多个关键技术领域取得突破,具体包括高精度绝对校准技术、远距离光纤传输的温度补偿、级联系统的噪声累积抑制以及基于无线链路的时频传递实现等。 展开更多
关键词 光纤 white Rabbit 时间同步 频率同步 分布式系统
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Asteroseismology of DAV white dwarf stars and G29–38
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作者 Yan-Hui Chen Yan Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第12期1438-1444,共7页
Asteroseismology is a powerful tool used for detecting the inner structure of stars, which is also widely used to study white dwarfs. We discuss the asteroseismology of DAV stars. The period-to-period fitting method i... Asteroseismology is a powerful tool used for detecting the inner structure of stars, which is also widely used to study white dwarfs. We discuss the asteroseismology of DAV stars. The period-to-period fitting method is discussed in detail, including its reliability in detecting the inner structure of DAV stars. If we assume that all observed modes of some DAV stars are the l = I cases, the errors associated with model fitting will be always large. If we assume that the observed modes are com- posed of I = 1 and 2 modes, the errors associated with model fitting in this case will be small. However, there will be modes identified as l = 2 that do not have ob- served quintuplets. G29-38 has been observed spectroscopically and photometrically for many years. Thompson et al. made 1 modes identifications in the star through the limb darkening effect. With 11 known I modes, we also study the asteroseismology of G29-38, which reduces the blind l fittings and is a fair choice. Unfortunately, our two best-fitting models are not in line with the previous atmospheric results. Based on factors like only a few observed modes, stability and identification of eigenmodes, identification of spherical degrees, construction of physical and realistic models and so on, detecting the inner structure of DAV stars by asteroseismology needs further development. 展开更多
关键词 stars oscillations (including pulsations) - stars individual (G29-38)- white dwarfs
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Theoretical Models of Highly Magnetic White Dwarf Stars with Non-Polytropic Equation of State
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作者 Hridaya Shah Kunnat Sebastian 《Journal of Modern Physics》 2020年第9期1466-1491,共26页
Super-massive white dwarf (WD) stars in the mass range 2.4 - 2.8 solar masses are believed to be the progenitors of “super-luminous” Type Ia supernovae according to a hypothesis proposed by some researchers. They th... Super-massive white dwarf (WD) stars in the mass range 2.4 - 2.8 solar masses are believed to be the progenitors of “super-luminous” Type Ia supernovae according to a hypothesis proposed by some researchers. They theorize such a higher mass of the WD due to the presence of a very strong magnetic field inside it. We revisit their first work on magnetic WDs (MWDs) and present our theoretical results that are very different from theirs. The main reason for this difference is in the use of the equation of state (EoS) to make stellar models of MWDs. An electron gas in a magnetic field is Landau quantized and hence, the resulting EoS becomes non-polytropic. By constructing models of MWDs using such an EoS, we highlight that a strong magnetic field inside a WD would make the star super-massive. We have found that our stellar models do indeed fall in the mass range given above. Moreover, we are also able to address an observational finding that the mean mass of MWDs are almost double that of non-magnetic WDs. Magnetic field changes the momentum-space of the electrons which in turn changes their density of states (DOS), and that in turn changes the EoS of matter inside the star. By correlating the magnetic DOS with the non-polytropic EoS, we were also able to find a physical reason behind our theoretical result of super-massive WDs with strong magnetic fields. In order to construct these models, we have considered different equations of state with at most three Landau levels occupied and have plotted our results as mass-radius relations for a particular chosen value of maximum Fermi energy. Our results also show that a multiple Landau-level system of electrons leads to such an EoS that gives multiple branches in the mass-radius relations, and that the super-massive MWDs are obtained when the Landau-level occupancy is limited to just one level. Finally, our theoretical results can be explained solely on the basis of quantum and statistical mechanics that warrant no assumptions regarding stars. 展开更多
关键词 white Dwarf Star Magnetic Field Landau Levels Equation of State Density of States
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Formation and Evolution of Stars and Galaxies in the Cosmic Environment 被引量:1
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作者 Cui-xiang Zhong 《Journal of Environmental Science and Engineering(B)》 2025年第2期53-64,共12页
With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unk... With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unknown.Therefore,by studying the formation and orbital transformation mechanism of satellites,planets and stars,the author puts forward a new theory on the formation and evolution of stars and galaxies,thus revealing the hierarchical structure of galaxies and the formation and evolution laws of main sequence stars,red giants,white dwarfs,black dwarfs,supernovae,neutron stars,black holes and quasars.Some special phenomena in the course of star formation and evolution,such as sunspots,flares,fast radio bursts and gamma-ray bursts,have also been revealed. 展开更多
关键词 SUNSPOT red giant white Dwarf SUPERNOVA neutron star QUASAR fast radio burst gamma-ray burst.
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The Mini-SiTian Array:White Paper 被引量:1
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作者 Henggeng Han Yang Huang +11 位作者 Beichuan Wang Yongkang Sun Cunshi Wang Zhirui Li Junjie Jin Ningchen Sun Kai Xiao Min He Hongrui Gu Zexi Niu Hong Wu Jifeng Liu 《Research in Astronomy and Astrophysics》 2025年第4期94-99,共6页
This paper outlines the scientific goals and observational strategies of the Mini-SiTian Array.Mounted at Xinglong Observatory,the Mini-SiTian Array consists of three 30 cm telescopes and has been in operation since 2... This paper outlines the scientific goals and observational strategies of the Mini-SiTian Array.Mounted at Xinglong Observatory,the Mini-SiTian Array consists of three 30 cm telescopes and has been in operation since 2022.The large field of view,combined with the capability for multi-band photometric observations,enables the Mini-SiTian Array to perform rapid follow-up observations to identify optical counterparts of gravitational waves,capture the early light curves of tidal disruption events and supernovae,and monitor stellar flares,Be star outbursts,and cataclysmic variable stars,although its limiting magnitude is not very deep.By collaborating with the Xinglong2.16 m telescope and leveraging a real-time image processing pipeline,simultaneous photometric and spectroscopic observations could be performed to reveal their underlying physical mechanisms.The observational and research experience provides critical guidance for the implementation of the full-scale SiTian project in the future. 展开更多
关键词 telescopes stars:variables:general stars:flare (stars:)supernovae:general
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Producing Type Ia Supernovae from Hybrid CONe White Dwarfs with Mainsequence Binary Companions at Low Metallicity of Z=0.0001
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作者 Boyang Guo Xiangcun Meng +2 位作者 Zhijia Tian Jingxiao Luo Zhengwei Liu 《Research in Astronomy and Astrophysics》 2025年第1期344-356,共13页
The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white... The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M_(⊙)yr^(−1),our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10^(−4) yr^(−1).In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times. 展开更多
关键词 methods numerical-(stars:)binaries(including multiple) close-stars evolution-(stars:)supernovae general-(stars:)white dwarfs
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Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions
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作者 Narek Manukjan Daniel Fulton +2 位作者 Zubair Ahmed WMatthijs Blankesteijn Sébastien Foulquier 《Neural Regeneration Research》 SCIE CAS 2025年第1期191-192,共2页
As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming cle... As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of cSVD.The term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018). 展开更多
关键词 PATHOLOGY BECOMING white
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Difficulties of Two Exploding White Dwarfs to Account for Type Ia Supernovae with Bimodal Nebular Emission Profiles
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作者 Jessica Braudo Noam Soker 《Research in Astronomy and Astrophysics》 2025年第6期149-154,共6页
We use a simple dynamical scheme to simulate the ejecta of type Ⅰa supernova(SN Ia) scenarios with two exploding white dwarfs(WDs) and find that the velocity distribution of the ejecta has difficulties accounting for... We use a simple dynamical scheme to simulate the ejecta of type Ⅰa supernova(SN Ia) scenarios with two exploding white dwarfs(WDs) and find that the velocity distribution of the ejecta has difficulties accounting for bimodal emission line profiles with a large separation between the two emission peaks.The essence of the dynamical code is in including the fact that the ejecta does not leave the system instantaneously.We find that the final separation velocity between the centers of masses of the two WDs' ejecta is ≃80% of the pre-explosion WDs' orbital velocity,i.e.,we find separation velocities of 4200-5400 km s^(-1) for two WDs of masses M_(1)=M_(2)=0.94 M⊙.The lower separation velocities we find challenge scenarios with two exploding WDs to explain bimodal emission line profiles with observed velocity separations of up to ≃7000 km s^(-1).Only the mass in the ejecta of one WD with an explosion velocity lower than the separation velocity contributes to one peak of the bimodal profile;this is the inner ejecta.We find the inner ejecta to be only≲15% of the ejecta mass in energetic explosions.Less energetic explosions yield higher inner mass but lower separation velocities.We encourage searching for alternative explanations of bimodal line profiles. 展开更多
关键词 (stars:)white dwarfs-(stars:)supernovae general-(stars:)binaries(including multiple) close
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Supplementation of serine in low-gossypol cottonseed meal-based diet improved egg white gelling and rheological properties by regulating ovomucin synthesis and magnum physiological function in laying hens 被引量:1
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作者 Jianmin Zhou Yu Fu +5 位作者 Uchechukwu Edna Obianwuna Jing Wang Haijun Zhang Xiubo Li Guanghai Qi Shugeng Wu 《Journal of Integrative Agriculture》 2025年第3期1152-1166,共15页
This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the... This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the effects.A total of 288 Hy-Line Brown layers were randomly assigned into 3 treatments and respectively offered soybean meal(SBM)-based diet,LCSM-based diet,and LCSM-based diet supplemented with 0.435%L-Ser.Dietary Ser supplementation reversed the decrease in quality indices of albumen,including the proportion of thick albumen(P<0.05),thick-to-thin ratio(P<0.05),albumen height(P<0.05),Haugh unit(P<0.05),and apparent viscosity that were caused by LCSM intake.Also,dietary Ser supplementation mitigated the LCSM-induced reduction in ovomucin content of the albumen(P<0.05).FT-IR analysis of ovomucin revealed differences in second derivative spectra at 1,200-800 cm^(-1) between birds received SBM-and LCSM-based diets,meanwhile,the α-helix of ovomucin was decreased by LCSM but increased by Ser addition(P<0.05).Furthermore,Ser addition up-regulated the mRNA expression of β-ovomucin in magnum mucosa at 2 and 7.5 h post-oviposition(P<0.05).Ser mitigated the LCSMinduced impairment of magnum epithelium,increased goblet cell counts(P<0.05),and up-regulated the expression of occludin,mucin 2,and the relevant glycosyltransferases for O-glycosylation in magnum mucosa(P<0.05).Conclusively,the alleviating effect of Ser on declining albumen quality due to dietary LCSM,could be explained by the efficacy of Ser in regulating ovomucin synthesis.This regulation occurred at the levels of transcription and posttranscriptional O-glycosylation modification ofβ-ovomucin,while positive effect on magnum morphology and barrier function could also in part account for the ovomucin content.This would provide a promising research direction on the adoption of nutritional interventions for manipulation of egg white quality from perspectives of albumen protein synthesis. 展开更多
关键词 egg white quality low-gossypol cottonseed meal laying hen OVOMUCIN SERINE
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