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尾部风险视角下的金融系统性风险研究——基于随机森林法和GARCH-MIDAS模型的分析
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作者 高杰英 周圣杰 徐昕 《现代金融研究》 北大核心 2025年第7期30-44,共15页
本研究测度了2010-2022年我国金融机构尾部风险水平,刻画了金融业和金融子行业两个维度的尾部风险溢出特征,并进一步采用随机森林法与GARCH-MIDAS模型研究不同频率下宏观驱动因子对金融系统性风险的影响。研究发现:第一,金融系统性风险... 本研究测度了2010-2022年我国金融机构尾部风险水平,刻画了金融业和金融子行业两个维度的尾部风险溢出特征,并进一步采用随机森林法与GARCH-MIDAS模型研究不同频率下宏观驱动因子对金融系统性风险的影响。研究发现:第一,金融系统性风险呈周期震荡特征,子行业风险溢出表现出阶段性的共振与分化;第二,金融系统性风险对国际金融渠道的宏观驱动因子更敏感,且不同子行业对宏观驱动因子的敏感性存在显著异质性;第三,资本流出与经济过热加剧金融系统不稳定性,但在极端情境下,避险资金逆流入境反而对我国系统性风险形成缓冲。 展开更多
关键词 尾部风险 系统性风险 宏观驱动因子 随机森林 garch-midas模型
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经济政策不确定性与比特币市场波动的跨国实证研究——基于GARCH-MIDAS模型的分析 被引量:1
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作者 杨洁萌 沈云淇 《上海经济研究》 北大核心 2025年第7期102-115,共14页
本文以作为私有数字货币代表的比特币为研究对象,分析经济政策不确定性(Economic Policy Uncertainty,EPU)对私有数字货币市场波动的影响。使用GARCH-MIDAS模型进行跨国实证分析,选取中国、美国、日本、德国、英国五国EPU指数,构建包含... 本文以作为私有数字货币代表的比特币为研究对象,分析经济政策不确定性(Economic Policy Uncertainty,EPU)对私有数字货币市场波动的影响。使用GARCH-MIDAS模型进行跨国实证分析,选取中国、美国、日本、德国、英国五国EPU指数,构建包含EPU的扩展波动率预测模型,发现EPU指数显著影响比特币的长期波动,其中美国EPU与比特币市场的波动性呈现高度正相关,符合全球私人数字货币市场对美国经济政策不确定性的高度敏感;而中国、德国EPU指数与比特币市场的波动性总体呈负相关,体现出比特币在特定市场的避险属性。相较于传统GARCH模型,包含EPU指数的GARCH-MIDAS模型在样本内和样本外预测中均表现出更高的精度,证明政策不确定性是驱动比特币市场波动的重要长期因素,为全球数字货币市场的监管政策制定和投资者的风险管理策略提供理论依据和实证支持。 展开更多
关键词 经济政策不确定性 比特币市场波动 garch-midas模型 波动率预测 跨国实证研究
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基于GARCH-MIDAS模型的经济政策不确定性和投资者情绪对原油价格波动的影响研究
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作者 陈亚琼 《电子商务评论》 2025年第4期402-412,共11页
原油作为全球最重要的能源之一,在经济和金融市场中具有举足轻重的地位。本文利用GARCH-MIDAS模型,深入探讨了2014年1月至2024年9月期间,我国经济政策不确定性和投资者情绪对原油价格波动的影响。研究表明:原油价格波动表现出显著的自... 原油作为全球最重要的能源之一,在经济和金融市场中具有举足轻重的地位。本文利用GARCH-MIDAS模型,深入探讨了2014年1月至2024年9月期间,我国经济政策不确定性和投资者情绪对原油价格波动的影响。研究表明:原油价格波动表现出显著的自相关性,且其长期趋势呈现负向特征。从短期来看,经济政策不确定性和投资者情绪显著影响原油价格波动,且正向冲击会加剧价格波动;从长期来看,经济政策不确定性对原油价格波动具有显著抑制作用,而投资者情绪不会显著影响原油价格波动。在经济政策高不确定性的情况下,投资者情绪会更显著地影响原油价格波动。本文不仅为讨论原油价格波动提供了新视角,也为实现风险控制或金融稳定提供了参考。Crude oil, as one of the world’s most crucial energy sources, holds a pivotal position in both economic and financial markets. This paper employs the GARCH-MIDAS model to conduct an in-depth analysis of the impact of economic policy uncertainty and investor sentiment on crude oil price volatility in China from January 2014 to September 2024. The study reveals that crude oil price volatility exhibits significant autocorrelation, with a long-term trend characterized by a negative trajectory. In the short term, crude oil prices are significantly influenced by economic policy uncertainty and investor sentiment, with positive shocks exacerbating price volatility. Over the long term, economic policy uncertainty exerts a negative influence on prices of crude oil, whereas the influence of investor sentiment does not appear to be statistically significant. Additionally, during periods of high economic policy uncertainty, the attention of domestic investors increases and is reflected in the volatility of crude oil prices. This paper not only offers a new perspective on the discussion of crude oil price volatility but also provides insights for achieving risk control or financial stability. 展开更多
关键词 garch-midas模型 经济政策不确定性 投资者情绪 原油价格波动
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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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Design optimization and FEA of B-6 and B-7 levels ballistics armor:A modelling approach
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作者 Muhammad Naveed CHU Jinkui +1 位作者 Atif Ur Rehman Arsalan Hyder 《大连理工大学学报》 北大核心 2026年第1期66-77,共12页
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl... Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor. 展开更多
关键词 radiator armor ballistics simulation Johnson-Cook model armor-piercing projectile perforated D-shaped armor plate
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Do Higher Horizontal Resolution Models Perform Better?
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作者 Shoji KUSUNOKI 《Advances in Atmospheric Sciences》 2026年第1期259-262,共4页
Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(... Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(2025)].In relation to seasonal forecasting and climate projection in the East Asian summer monsoon season,proper simulation of the seasonal migration of rain bands by models is a challenging and limiting factor[section 7.1 in Wang et al.(2025)]. 展开更多
关键词 enhancing model resolution refinement data assimilation systems section climate model climate projection higher horizontal resolution seasonal forecasting simulation seasonal migration rain bands model resolution
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A Predictive Model for the Elastic Modulus of High-Strength Concrete Based on Coarse Aggregate Characteristics
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作者 LI Liangshun LI Huajian +2 位作者 HUANG Fali YANG Zhiqiang DONG Haoliang 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期121-137,共17页
To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the stre... To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the strength and elastic modulus of mortar and concrete prepared with mechanism aggregates of the corresponding lithology,and the stress-strain curves of concrete were investigated.In this paper,a coarse aggregate and mortar matrix bonding assumption is proposed,and a prediction model for the elastic modulus of mortar is established by considering the lithology of the mechanism sand and the slurry components.An equivalent coarse aggregate elastic modulus model was established by considering factors such as coarse aggregate particle size,volume fraction,and mortar thickness between coarse aggregates.Based on the elastic modulus of the equivalent coarse aggregate and the remaining mortar,a prediction model for the elastic modulus of the two and three components of concrete in series and then in parallel was established,and the predicted values differed from the measured values within 10%.It is proposed that the coarse aggregate elastic modulus in highstrength concrete is the most critical factor affecting the elastic modulus of concrete,and as the coarse aggregate elastic modulus increases by 27.7%,the concrete elastic modulus increases by 19.5%. 展开更多
关键词 elastic modulus prediction model MINERALOGICAL influence mechanism
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Global Stability of Traveling Wavefronts for a Belousov-Zhabotinsky Model with Mixed Nonlocal and Degenerate Diffusions
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作者 Yuting YANG Guobao ZHANG 《Journal of Mathematical Research with Applications》 2026年第1期87-102,共16页
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal... In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique. 展开更多
关键词 Belousov-Zhabotinsky model nonlocal diffusion stability comparison principle weighted energy
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An effective deep-learning prediction of Arctic sea-ice concentration based on the U-Net model
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作者 Yifan Xie Ke Fan +2 位作者 Hongqing Yang Yi Fan Shengping He 《Atmospheric and Oceanic Science Letters》 2026年第1期34-40,共7页
Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiote... Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiotemporal distribution of Arctic SIC is more challenging than predicting its total extent.In this study,spatiotemporal prediction models for monthly Arctic SIC at 1-to 3-month leads are developed based on U-Net-an effective convolutional deep-learning approach.Based on explicit Arctic sea-ice-atmosphere interactions,11 variables associated with Arctic sea-ice variations are selected as predictors,including observed Arctic SIC,atmospheric,oceanic,and heat flux variables at 1-to 3-month leads.The prediction skills for the monthly Arctic SIC of the test set(from January 2018 to December 2022)are evaluated by examining the mean absolute error(MAE)and binary accuracy(BA).Results showed that the U-Net model had lower MAE and higher BA for Arctic SIC compared to two dynamic climate prediction systems(CFSv2 and NorCPM).By analyzing the relative importance of each predictor,the prediction accuracy relies more on the SIC at the 1-month lead,but on the surface net solar radiation flux at 2-to 3-month leads.However,dynamic models show limited prediction skills for surface net solar radiation flux and other physical processes,especially in autumn.Therefore,the U-Net model can be used to capture the connections among these key physical processes associated with Arctic sea ice and thus offers a significant advantage in predicting Arctic SIC. 展开更多
关键词 Arctic sea-ice concentration Deep-learning prediction U-Net model CFSv2 NorCPM
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Tail clamping induces anxiety-like behaviors and visceral hypersensitivity in rat models of non-erosive reflux disease
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作者 Mi Lv Xin Liu +6 位作者 Kai-Yue Huang Yu-Xi Wang Zheng Wang Li-Li Han Hui Che Lin Lv Feng-Yun Wang 《World Journal of Psychiatry》 2026年第1期356-368,共13页
BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models ... BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models are unclear.AIM To establish a translational NERD rat model with anxiety comorbidity via tail clamping and study corticotropin-releasing hormone(CRH)-mediated neuroimmune pathways in visceral hypersensitivity and esophageal injury.METHODS Sprague-Dawley(SD)and Wistar rats were grouped into sham,model,and modified groups(n=10 each).The treatments for the modified groups were as follows:SD rats received ovalbumin/aluminum hydroxide suspension+acid perfusion±tail clamping(40 minutes/day for 7 days),while Wistar rats received fructose water+tail clamping.Esophageal pathology,visceral sensitivity,and behavior were assessed.Serum CRH,calcitonin gene-related peptide(CGRP),5-hydroxytryptamine(5-HT),and mast cell tryptase(MCT)and central amygdala(CeA)CRH mRNA were measured via ELISA and qRT-PCR.RESULTS Tail clamping induced anxiety,worsening visceral hypersensitivity(lower abdominal withdrawal reflex thresholds,P<0.05)and esophageal injury(dilated intercellular spaces and mitochondrial edema).Both models showed raised serum CRH,CGRP,5-HT,and MCT(P<0.01)and CeA CRH mRNA expression(P<0.01).Behavioral tests confirmed anxiety-like phenotypes.NERD-anxiety rats showed clinical-like symptom severity without erosion.CONCLUSION Tail clamping induces anxiety in NERD models,worsening visceral hypersensitivity via CRH neuroimmune dysregulation,offering a translational model and highlighting CRH as a treatment target. 展开更多
关键词 Non-erosive reflux disease Anxiety and depression Animal model Tail-clamping Corticotropin hormones
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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Growing a Rural Future--A young Ugandan channels insights from China’s model villages to build a more resilient,cooperative and forward-looking Busoga
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作者 LI XIAOYU 《ChinAfrica》 2026年第1期56-57,共2页
In the lush heart of Uganda’s Busoga sub-region,Isaac Imaka is charting a new course for rural development.After seven years in national media,he left the newsroom and stepped into the soil.The former reporter with t... In the lush heart of Uganda’s Busoga sub-region,Isaac Imaka is charting a new course for rural development.After seven years in national media,he left the newsroom and stepped into the soil.The former reporter with the Daily Monitor was driven by the belief that communities like his in Jinja North deserved more than chronic poverty and hand-to-mouth survival. 展开更多
关键词 community resilience Uganda rural development model villages rural future Busoga sub region cooperative development rural journalism
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Effects of noninvasive brain stimulation on motor functions in animal models of ischemia and trauma in the central nervous system
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作者 Seda Demir Gereon R.Fink +1 位作者 Maria A.Rueger Stefan J.Blaschke 《Neural Regeneration Research》 2026年第4期1264-1276,共13页
Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of kn... Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation. 展开更多
关键词 noninvasive brain stimulation preclinical modeling STROKE transcranial direct current stimulation transcranial magnetic stimulation traumatic brain injury
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Risk factors for paternal perinatal depression in Chinese advanced maternal age couples:A regression mixture model
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作者 Xing Yin Juan Du +1 位作者 Shao-Lian Cai Xing-Qiang Chen 《World Journal of Psychiatry》 2026年第1期267-277,共11页
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn... BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support. 展开更多
关键词 Advanced maternal age Paternal perinatal depression Fathers’mental health Regression mixture model Advanced-age pregnancy Latent profile analysis
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Novel therapies for myasthenia gravis:Translational research from animal models to clinical application
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作者 Benedetta Sorrenti Christian Laurini +4 位作者 Luca Bosco Camilla Mirella Maria Strano Adele Ratti Yuri Matteo Falzone Stefano Carlo Previtali 《Neural Regeneration Research》 2026年第5期1834-1848,共15页
Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in ... Myasthenia gravis is a chronic autoimmune disorder that affects the neuromuscular junction leading to fluctuating skeletal muscle fatigability. The majority of myasthenia gravis patients have detectable antibodies in their serum, targeting acetylcholine receptor, muscle-specific kinase, or related proteins. Current treatment for myasthenia gravis involves symptomatic therapy, immunosuppressive drugs such as corticosteroids, azathioprine, and mycophenolate mofetil, and thymectomy, which is primarily indicated in patients with thymoma or thymic hyperplasia. However, this condition continues to pose significant challenges including an unpredictable and variable disease progression, differing response to individual therapies, and substantial longterm side effects associated with standard treatments(including an increased risk of infections, osteoporosis, and diabetes), underscoring the necessity for a more personalized approach to treatment. Furthermore, about fifteen percent of patients, called “refractory myasthenia gravis patients”, do not respond adequately to standard therapies. In this context, the introduction of molecular therapies has marked a significant advance in myasthenia gravis management. Advances in understanding myasthenia gravis pathogenesis, especially the role of pathogenic antibodies, have driven the development of these biological drugs, which offer more selective, rapid, and safer alternatives to traditional immunosuppressants. This review aims to provide a comprehensive overview of emerging therapeutic strategies targeting specific immune pathways in myasthenia gravis, with a particular focus on preclinical evidence, therapeutic rationale, and clinical translation of B-cell depletion therapies, neonatal Fc receptor inhibitors, and complement inhibitors. 展开更多
关键词 acetylcholine receptor(AChR) animal models B-cell depletion biological therapies COMPLEMENT IMMUNOTHERAPY muscle-specific kinase(Mu SK) neonatal Fc receptor
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Human cerebral organoids:Complex,versatile,and human-relevant models of neural development and brain diseases
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作者 Raquel Coronel Rosa González-Sastre +8 位作者 Patricia Mateos-Martínez Laura Maeso Elena Llorente-Beneyto Sabela Martín-Benito Viviana S.Costa Gagosian Leonardo Foti Ma Carmen González-Caballero Victoria López-Alonso Isabel Liste 《Neural Regeneration Research》 2026年第3期837-854,共18页
The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cereb... The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cerebral organoids have emerged as valuable tools offering a more complex,versatile,and human-relevant system than traditional animal models,which are often unable to replicate the intricate architecture and functionality of the human brain.Since human cerebral organoids are a state-of-the-art model for the study of neurodevelopment and different pathologies affecting the brain,this field is currently under constant development,and work in this area is abundant.In this review,we give a complete overview of human cerebral organoids technology,starting from the different types of protocols that exist to generate different human cerebral organoids.We continue with the use of brain organoids for the study of brain pathologies,highlighting neurodevelopmental,psychiatric,neurodegenerative,brain tumor,and infectious diseases.Because of the potential value of human cerebral organoids,we describe their use in transplantation,drug screening,and toxicology assays.We also discuss the technologies available to study cell diversity and physiological characteristics of organoids.Finally,we summarize the limitations that currently exist in the field,such as the development of vasculature and microglia,and highlight some of the novel approaches being pursued through bioengineering. 展开更多
关键词 assembloids BIOENGINEERING challenges disease modeling drug screening and toxicology human brain organoids human pluripotent stem cells neurodegenerative diseases NEURODEVELOPMENT VASCULARIZATION
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经济不确定性是股市波动的因子吗?——基于GARCH-MIDAS模型的分析 被引量:53
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作者 夏婷 闻岳春 《中国管理科学》 CSSCI CSCD 北大核心 2018年第12期1-11,共11页
本文运用混频模型(GARCH-MIDAS)分析了经济不确定性对中国股市波动率的影响。经济不确定性包括宏观经济不确定性和经济政策不确定性两方面。总体来说,经济不确定性会影响中国股市的波动,但强度有限,且A股、B股间表现出差异。经济运行(IP... 本文运用混频模型(GARCH-MIDAS)分析了经济不确定性对中国股市波动率的影响。经济不确定性包括宏观经济不确定性和经济政策不确定性两方面。总体来说,经济不确定性会影响中国股市的波动,但强度有限,且A股、B股间表现出差异。经济运行(IP)和消费(inf)中的不确定性是A股、B股共同的波动因子,且IP的贡献度最高;货币政策(IR)、中国经济政策不确定性(CEPU)对A股无显著影响,但会显著影响B股的长期波动趋势;美国经济政策不确定性(AEPU)的影响则不显著。加入显著性指标有助于提高波动率的预测精度,混频模型为分析股市波动中的长期趋势和短期波动提供了一个新视角,有助于识别股市波动中的经济影响因素。 展开更多
关键词 股市波动 宏观经济不确定性 经济政策不确定性 garch-midas
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时变风险厌恶与黄金期货市场波动率--基于GARCH-MIDAS模型的实证研究 被引量:1
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作者 吴鑫育 张静 《沈阳大学学报(社会科学版)》 2022年第6期605-613,共9页
黄金作为特殊的贵金属,一直被投资者视为拥有“避风港”特征的有效避险工具。将时变风险厌恶指数(R_(A))引入GARCH-MIDAS模型中,研究R_(A)对黄金期货波动率的影响及预测作用。采用损失函数和模型置信集(MCS)评价不同模型的样本外预测精... 黄金作为特殊的贵金属,一直被投资者视为拥有“避风港”特征的有效避险工具。将时变风险厌恶指数(R_(A))引入GARCH-MIDAS模型中,研究R_(A)对黄金期货波动率的影响及预测作用。采用损失函数和模型置信集(MCS)评价不同模型的样本外预测精度。实证结果表明:R_(A)对黄金期货市场波动有显著的正向影响;相比于其他模型,引入R_(A)的GARCH-MIDAS-RA模型拥有更好的参数估计结果和预测结果。 展开更多
关键词 黄金期货 时变风险厌恶 garch-midas模型 波动率 MCS检验
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比特币对我国股票市场波动性的影响——基于双重非对称GARCH-MIDAS模型的实证研究 被引量:1
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作者 吴鑫育 王小娜 《重庆理工大学学报(社会科学)》 2022年第8期65-75,共11页
在考虑股票市场收益率以及波动率非对称性的基础上,通过采用上证综合指数、五大行业股票指数(工业、商业、房地产业、公共事业和其他行业)以及比特币数据,构建双重非对称GARCH-MIDAS(DAGARCH-MIDAS)模型,实证研究比特币对我国整体股票... 在考虑股票市场收益率以及波动率非对称性的基础上,通过采用上证综合指数、五大行业股票指数(工业、商业、房地产业、公共事业和其他行业)以及比特币数据,构建双重非对称GARCH-MIDAS(DAGARCH-MIDAS)模型,实证研究比特币对我国整体股票市场在不同样本期间(全样本期、中国股市崩盘的2014—2016年、比特币依托的区块链技术火热的2016—2019年)和对不同行业股票市场在全样本期间的影响。研究结果表明:在全样本期,比特币对我国整体股票市场具有显著的正向影响;在2014—2016年的子样本期,比特币对我国股市的正向影响更为显著;在2016—2019年的子样本期,比特币对我国股市具有显著的负向影响;比特币对我国工业、商业、房地产业和其他行业的股票市场均具有显著的正向且相似的影响,但对我国公共事业股票市场并没有显著冲击。 展开更多
关键词 比特币 中国股市 非对称性 garch-midas模型 区块链
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