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Perspectives on a collaborative Canada-China research program on diagnostic biomarkers for pre-dementia stages of Alzheimer’s disease
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作者 Serge Gauthier Jianping Jia +8 位作者 Sylvie Belleville Simon Cloutier Dessa Sadovnick Colleen Guimond Laura Robb Mario Masellis Guy A Rouleau Liyong Wu Pedro Rosa-Neto 《Journal of Translational Neuroscience》 2017年第3期1-6,共6页
As biomarkers are important in the early diagnosis ofAlzheimer’s disease (AD), the frst collab-orative work of recruiting early-onset familial AD (EO-FAD) families in Canada and China was initiated in 2012. The r... As biomarkers are important in the early diagnosis ofAlzheimer’s disease (AD), the frst collab-orative work of recruiting early-onset familial AD (EO-FAD) families in Canada and China was initiated in 2012. The registration networks have collected hundreds of pedigrees, for which genetic screening, neuropsycholog-ical tests and amyloid and tau imaging was used to study diagnostic biomarkers for preclinical and mild cognitive impairment (MCI) stages of AD. Besides identifying ped-igrees with novel mutations in presenilins (PSENs)/amy-loid precursor protein (APP), the program has benefted training of Chinese research fellows, AD clinical trials forprevention,the ethical concernsfor clinical fndings, and other collaborative projects with Chinese investiga-tors. Further research of the collaborative program may facilitate the testing and clinical use of novel treatments for EOFAD and late onset AD and contribute to dementia prevention strategies in Canada and China. 展开更多
关键词 registration network early-onset fa-milial Alzheimer’s disease (EOFAD) mutation neuro-psychological testing
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Comparison of aerosol optical depth of UV-B Monitoring and Research Program (UVMRP), AERONET and MODIS over continental United States
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作者 Hongzhao TANG Maosi CHEN +1 位作者 John DAVIS Wei GAO 《Frontiers of Earth Science》 SCIE CAS CSCD 2013年第2期129-140,共12页
The concern about the role of aerosols as to their effect in the Earth-Atmosphere system requires observation at multiple temporal and spatial scales. The Moderate Resolution Imaging Spectroradiameters (MODIS) is th... The concern about the role of aerosols as to their effect in the Earth-Atmosphere system requires observation at multiple temporal and spatial scales. The Moderate Resolution Imaging Spectroradiameters (MODIS) is the main aerosol optical depth (AOD) monitoring satellite instrument, and its accuracy and uncertainty need to be validated against ground based measurements routinely. The comparison between two ground AOD measurement programs, the United States Department of Agriculture (USDA) Ultmviolet-B Monitoring and Research Program (UVMRP) and the Aerosol Robotic Network (AERONET) program, confirms the consistency between them. The intercomparison between the MODIS AOD, the AERONET AOD, and the UVMRP AOD suggests that the UVMRP AOD measurements are suited to be an alternative ground-based validation source for satellite AOD products. The experiments show that the spatial-temporal dependency between the MODIS AOD and the UVMRP AOD is positive in the sense that the MODIS AOD compare more favorably with the UVMRP AOD as the spatial and temporal intervals are increased. However, the analysis shows that the optimal spatial interval for all time windows is defined by an angular subtense of around 1° to 1.25°, while the optimal time window is around 423 to 483 minutes at most spatial intervals. The spatial-temporal approach around 1.25° & 423 minutes shows better agreement than the prevalent strategy of 0.25° & 60 minutes found in other similar investigations. 展开更多
关键词 aerosol optical depth (AOD) United States Department of Agriculture (USDA) UV-B Monitoring andResearch Program (UVMRP) Aerosol Robotic Network (AERONET) Moderate Resolution Imaging Spectmradiameters (MODIS) validation spatial-temporal approach
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Feeding rumen-protected choline during the periconceptional period programs postnatal phenotype of suckled beef calves
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作者 Masroor Sagheer McKenzie L.J.Haimon +9 位作者 Samuel Hincapie Montoya Daniella Heredia Federico Tarnonsky Mauro E.Venturini Angella Gonella-Diaza Nicolas DiLorenzo Joseph W.McFadden Gabriela Dalmaso de Melo Ky G.Pohler Peter J.Hansen 《Journal of Animal Science and Biotechnology》 2025年第4期1696-1703,共8页
Background Supplementation of choline chloride in culture medium programs the preimplantation bovine embryo to increase weaning weight of the resultant calf.Here,it was hypothesized that similar programming actions of... Background Supplementation of choline chloride in culture medium programs the preimplantation bovine embryo to increase weaning weight of the resultant calf.Here,it was hypothesized that similar programming actions of choline can be induced by feeding rumen-protected choline(RPC)to beef cows during the periconceptional period.Results A preliminary experiment was conducted to determine changes in circulating concentrations of choline and its metabolites after RPC supplementation.Suckled beef cows were individually fed 0,30,60,and 90 g of RPC(i.e.,0,8.6,17.3 and 25.9 g choline chloride)and blood samples were collected at random times after feeding.There were no differences in plasma concentrations of choline or its metabolites between groups.In the second experiment,effects of feeding 60 g/d RPC from d-1 to 7 relative to timed artificial insemination were examined for suckled beef cows.Feeding RPC did not affect pregnancy or calving rates,pregnancy losses,plasma concentrations of pregnancy-associated glycoproteins,gestation length or calf birth weight.Calves from RPC fed dams were lighter than control calves at~118 days of age(range 75–150;age included in the statistical model)and at weaning at~248 days of age.There was no effect of treatment on hip height at~118 days of age although there was a trend for RPC calves to be shorter at weaning.Weight/height ratio was lower for RPC than control at both 118 and 248 days of age.Treatment did not affect testis weight at~118 days of age.Conclusions Supplementation of RPC during the periconceptional period programmed development to alter calf phenotype in the postnatal period.The net result,reduced body weight,was the opposite of the phenotype caused by the addition of choline to embryo culture medium. 展开更多
关键词 Beef cattle CHOLINE PREGNANCY PROGRAMMING
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Schizophrenia:Genetics,neurological mechanisms,and therapeutic approaches 被引量:1
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作者 Debbie Xiu En Lim Shi Yun Yeo +3 位作者 Zhen You Ashley Chia Aaron Zefrin Fernandis Jimmy Lee John Jia En Chua 《Neural Regeneration Research》 2026年第3期1089-1103,共15页
Schizophrenia is a complex psychiatric disorder marked by positive and negative symptoms,leading to mood disturbances,cognitive impairments,and social withdrawal.While anti-psychotic medications remain the cornerstone... Schizophrenia is a complex psychiatric disorder marked by positive and negative symptoms,leading to mood disturbances,cognitive impairments,and social withdrawal.While anti-psychotic medications remain the cornerstone of treatment,they often fail to fully address certain symptoms.Additionally,treatment-resistant schizophrenia,affecting 30%-40%of patients,remains a substantial clinical challenge.Positive,negative symptoms and cognitive impairments have been linked to disruptions in the glutamatergic,serotonin,GABAergic,and muscarinic pathways in the brain.Recent advances using genome-wide association study and other approaches have uncovered a significant number of new schizophrenia risk genes that uncovered new,and reinforced prior,concepts on the genetic and neurological underpinnings of schizophrenia,including abnormalities in synaptic function,immune processes,and lipid metabolism.Concurrently,new therapeutics targeting different modalities,which are expected to address some of the limitations of anti-psychotic drugs currently being offered to patients,are currently being evaluated.Collectively,these efforts provide new momentum for the next phase of schizophrenia research and treatment. 展开更多
关键词 NEUROINFLAMMATION neuropsychiatric disorders neurotransmitter pathways schizophrenia risk genes treatment resistance
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《周易》的生死观与“生生”哲学
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作者 李善庆 《枣庄学院学报》 2026年第1期119-123,共5页
《周易》的死亡观与儒家生死哲学一脉相承,其特点在于重视祭祀与丧礼,但避谈来世,体现了东亚思想的独特性。现有研究多聚焦“生生”哲学,对“死亡”的探讨则相对匮乏,可能与《周易》强调“变化”、否定终极终结的哲学倾向有关。然而,作... 《周易》的死亡观与儒家生死哲学一脉相承,其特点在于重视祭祀与丧礼,但避谈来世,体现了东亚思想的独特性。现有研究多聚焦“生生”哲学,对“死亡”的探讨则相对匮乏,可能与《周易》强调“变化”、否定终极终结的哲学倾向有关。然而,作为应对灾祸之书,《周易》理应对“死亡”这一最大之“凶”提出应对之道。它既不追求肉体永生,也不许诺来世,而是通过“阴阳互根”的辩证结构,将死亡视为生命的内在组成部分。死亡既属自然现象、不可单纯言“凶”,又从人生角度难以回避其凶性,这一矛盾需从整合视角理解。“生生之谓易”应在生死统一的框架中解读:所谓“生生”,并非仅指向“生”,而是阴阳合一、生死相综之道,体现于永恒变化的当下瞬间。在这种生生的哲学中,“瞬间”作为绝对的实在是“真”,而“永恒”不是遥远的彼岸,而是作为变化现场的主体存在于人自身之中。 展开更多
关键词 生死 生生 瞬间 周易 时中
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Busan Atmosphere Cryosphere Ocean Conference BACO-25:Our Interconnected Earth
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作者 Keith ALVERSON Silvia BLANC +1 位作者 Richard ESSERY Myong-In LEE 《Advances in Atmospheric Sciences》 2026年第5期1095-1101,共7页
The IUGG Associations for Atmosphere,Oceans and Cryosphere—IAMAS,IAPSO and IACS—held a Joint Scientific Assembly in Busan,South Korea,from 20 to 25 July 2025.This was the first joint assembly of all three associatio... The IUGG Associations for Atmosphere,Oceans and Cryosphere—IAMAS,IAPSO and IACS—held a Joint Scientific Assembly in Busan,South Korea,from 20 to 25 July 2025.This was the first joint assembly of all three associations since 2009,when they met in Montreal,Canada.It was the first time any of the associations had been hosted in Korea,and it had been two decades since any of them had met in Asia.The choice of Busan as the venue supported high levels of participation and smooth conference operations.The Local Organizing Committee,chaired by Prof.Kyung-Ja Ha of Pusan National University,oversaw the successful organization of the event.The assembly brought together 1725 participants in total,including 1282 researchers and 443 invited participants and individuals involved in side events,exhibitions,media coverage,and volunteer work.Participants came from 46 countries across Asia,Europe,North America,South America,Africa,and Oceania.IAMAS had 736 participants,IAPSO 321,and IACS 225.Survey data from 951 respondents revealed that Early Career Scientists,defined as those within 10 years of receiving their PhD,accounted for approximately 25%of participants.The demographic profile skewed young,with 66%of attendees in their 20s and 30s.The scientific program was organized by Prof.Seon-Ki Park(Chair),the Secretaries General from all three Associations,and the Local Organizing Committee.Reflecting the theme“Our Interconnected Earth,”the scientific program emphasized integrated approaches to climate systems,addressing climate change and environmental challenges through collaborative,transdisciplinary research. 展开更多
关键词 Interconnected Earth IAMAS Busan joint assembly ATMOSPHERE OCEAN CONFERENCE CRYOSPHERE
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Dynamic income patterns and risk of pancreatic and biliary tract cancers:A nationwide cohort study
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作者 Chung-woo Lee Kunhee Han +7 位作者 Yong-Moon Mark Park Ju-Yeong Park Kyu-Na Lee Dong Wook Shin Seon Mee Kim Youn Seon Choi Kyungdo Han Ga Eun Nam 《Chinese Journal of Cancer Research》 2026年第1期52-66,共15页
Objective:This study aimed to evaluate the associations of baseline income,cumulative income exposure,and income volatility with the incidence of pancreatic and biliary tract cancers in a nationwide Korean cohort.Meth... Objective:This study aimed to evaluate the associations of baseline income,cumulative income exposure,and income volatility with the incidence of pancreatic and biliary tract cancers in a nationwide Korean cohort.Methods:We analyzed 3,361,091 adults aged 30-65 years who underwent the 2012 National Health Insurance Service(NHIS)health screening.Income level was derived from insurance premium data assessed over the five years preceding baseline(2008-2012)and categorized into baseline income quartiles,cumulative exposure to low or high income,and income volatility based on annual percentage changes.Incident pancreatic and biliary tract cancers were identified using diagnostic codes and the copayment reduction registry.Associations were evaluated using Cox proportional hazards models with adjustment for demographic,lifestyle,and clinical covariates,and cumulative incidence was compared using Kaplan-Meier curves.Results:During a median follow-up of 9.6 years,14,469 pancreatic cancers and 6,647 biliary tract cancers were newly diagnosed.Lower baseline income was associated with a higher risk of pancreatic and biliary tract cancers,whereas sustained high-income exposure was associated with reduced risk.Cumulative low-income exposure showed a positive linear trend with pancreatic cancer incidence.Income volatility was modestly associated with pancreatic cancer and was positively associated with biliary tract cancer in the fully adjusted model.These associations were generally consistent across subgroups,with a stronger inverse association between prolonged high-income exposure and pancreatic cancer among individuals without diabetes.Conclusions:Income level and income stability were significantly associated with the incidence of pancreatic and biliary tract cancers.Lower baseline income was associated with higher risk,whereas sustained high-income exposure was protective.Income volatility was associated with increased cancer risk,particularly for biliary tract cancer.These findings highlight the importance of incorporating income dynamics into cancer prevention strategies and addressing socioeconomic instability among vulnerable populations. 展开更多
关键词 Pancreatic cancer biliary tract cancer socioeconomic status income level income dynamics income volatility
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Blood serum from individuals with Alzheimer’s disease alters microglial phagocytosis in vitro
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作者 Barbara Altendorfer Rodolphe Poupardin +21 位作者 Sophie Lefèvre-Arbogast Claudine Manach Dorrain Y.Low Mireia Urpi-Sarda Cristina Andres-Lacueva Raúl González-Domínguez Thomas K.Felder Julia Tevini Marco Zattoni Andreas Koller Reinhold Schmidt Paul J.Lucassen Silvie R.Ruigrok Chiara de Lucia Andrea Du Preez Catherine Helmer Jeanne Neuffer Cécile Proust-Lima Aniko Korosi Cécilia Samieri Sandrine Thuret Ludwig Aigner 《Neural Regeneration Research》 2026年第6期2433-2439,共7页
In Alzheimer’s disease,microglial phagocytosis is engaged in the pathogenesis as it clears abnormal protein accumulations,debris,and apoptotic cells in the early stages of Alzheimer’s disease,but fuels neuroinflamma... In Alzheimer’s disease,microglial phagocytosis is engaged in the pathogenesis as it clears abnormal protein accumulations,debris,and apoptotic cells in the early stages of Alzheimer’s disease,but fuels neuroinflammation and accelerates disease progression in later stages.In vivo parabiosis experiments in aged animals have demonstrated that blood-born factors modulate synaptic plasticity,neurogenesis,and microglial responses.We hypothesize that peripheral factors can modulate microglial function and thereby possibly influence Alzheimer’s disease pathology.The objective of this study is to investigate the effects of Alzheimer’s disease serum on microglial phagocytosis.Here,we use an immortalized human microglial cell line in an in vitro parabiosis assay to investigate the impact of the serum from individuals diagnosed with Alzheimer’s disease(n=30)and age-matched controls(n=30)(PRODEM study)on microglial phagocytosis.Exposure to Alzheimer’s disease serum increased microglial phagocytic uptake of pH-sensitive fluorescent particles and downregulated expression of the lysosomal master regulator transcription factor EB(TFEB)and of ATPase H^(+)transporting lysosomal V1 subunit B2(ATP6V1B2),a component of the vacuolar ATPase.To identify serum components that may relate to changes in phagocytosis,serum samples of the Three-City Study(3C Study)were used.In the 3C Study,blood samples were collected up to 12 years before the onset of cognitive decline or dementia and their serum metabolome is well-defined.Microglia exposed to the serum of future Alzheimer’s disease patients from the 3C Study displayed an increased phagocytic uptake compared with the serum of matched controls,depending on the presence of the apolipoprotein Eε4 allele in the Alzheimer’s disease patients.Furthermore,microglial phagocytosis correlated inversely with serum levels of the omega-3 fatty acid eicosapentaenoic acid.We confirmed this inverse correlation between eicosapentaenoic acid and phagocytosis in the serum samples of the PRODEM cohort.In addition,in vitro testing of eicosapentaenoic acid on microglial phagocytosis showed a concentration-dependent decrease in phagocytic uptake.In conclusion,following incubation with Alzheimer’s disease blood serum,we observed increased microglial phagocytic uptake and the downregulation of TFEB and ATP6V1B2,possibly indicating lysosomal dysfunction.Furthermore,microglial phagocytosis was inversely correlated with serum eicosapentaenoic acid levels,suggesting an important role for dietary eicosapentaenoic acid in microglial function. 展开更多
关键词 Alzheimer’s disease blood serum eicosapentaenoic acid in vitro parabiosis METABOLOME microglia omega-3 fatty acids PHAGOCYTOSIS
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Developing Genetic Variability of Quinoa (<i>Chenopodium quinoa</i>Willd.) with Gamma Radiation for Use in Breeding Programs 被引量:7
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作者 Luz Rayda Gomez-Pando Ana Eguiluz-de la Barra 《American Journal of Plant Sciences》 2013年第2期349-355,共7页
Quinoa (Chenopodium quinoa Willd.) is a staple food produced mainly by small-scale subsistence farmers in Peru’s highland. Dry seeds (cv. Pasankalla) were irradiated with doses of 150 Gy, 250 Gy and 350 Gy. In the M1... Quinoa (Chenopodium quinoa Willd.) is a staple food produced mainly by small-scale subsistence farmers in Peru’s highland. Dry seeds (cv. Pasankalla) were irradiated with doses of 150 Gy, 250 Gy and 350 Gy. In the M1 generation, the germination process was delayed with increasing radiation dose;seedling height, root length and leaf development were most reduced at 250 Gy and at 350 Gy, no plants survived. In M2, the maximum spectrum of chlorophyll mutations corresponded to 150 Gy and the maximum frequency to 250 Gy. The chlorine mutation was predominant, followed by xantha. Changes were registered for branch number, pedicel length, plant height, life-cycle duration, stem and foliage colour, and leaf morphology at the two doses, with improvements in plant type. More than one mutation per plant was found, especially at 250 Gy. In M3, the same spectrum of mutations was observed, along with a valuable change in grain colour. 展开更多
关键词 CHENOPODIUM QUINOA Gamma RAYS MUTANT
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Metabolic reprogramming in skeletal cell differentiation 被引量:2
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作者 Joshua C.Bertels Guangxu He Fanxin Long 《Bone Research》 SCIE CAS CSCD 2024年第3期539-554,共16页
The human skeleton is a multifunctional organ made up of multiple cell types working in concert to maintain bone and mineral homeostasis and to perform critical mechanical and endocrine functions.From the beginning st... The human skeleton is a multifunctional organ made up of multiple cell types working in concert to maintain bone and mineral homeostasis and to perform critical mechanical and endocrine functions.From the beginning steps of chondrogenesis that prefigures most of the skeleton,to the rapid bone accrual during skeletal growth,followed by bone remodeling of the mature skeleton,cell differentiation is integral to skeletal health. 展开更多
关键词 FUNCTIONS SKELETON PROGRAMMING
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An Overview of Tropical Cyclone and Tropical Meteorology Research Progress 被引量:18
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作者 陈联寿 罗会邦 +1 位作者 端义宏 余辉 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第3期505-514,共10页
There has been much progress in the study of tropical cyclones and tropical meteorology in China in the past few years. A new atmospheric field experiment of tropical cyclone landfall with the acronym of CLATEX (China... There has been much progress in the study of tropical cyclones and tropical meteorology in China in the past few years. A new atmospheric field experiment of tropical cyclone landfall with the acronym of CLATEX (China Landfalling Typhoon Experiment) was implemented in July-August 2002. The boundary layer characteristics of the target typhoon Vongfong and the mesoscale structural features of other land-falling typhoons were studied. In addition, typhoon track operational forecasting errors in the last decade have been reduced because the operational monitoring equipment and forecast techniques were improved. Some results from the research program on tropical cvclone landfall, structure and intensity change, inten-sification near coastal waters, interaction between tropical cyclone and mid-latitude circulation, and the interaction among different scales of motion are described in this paper. Four major meteorological scien-tific experiments in China with international cooperation were implemented in 1998: the South China Sea monsoon field experiment (SCSMEX), the Tibetan Plateau field experiment (TIPEX), the Huaihe River basin energy and water cycle experiment (HUBEX), and the South China heavy rain scientific experiment (HUAMEX). Although these field experiments have different scientific objectives, they commonly relate to monsoon activities and they interact with each other. The valuable intensive observation data that were obtained have already been shared internationally. Some new findings have been published recently. Other research work in China, such as the tropical air-sea interaction, tropical atmospheric circulation, and weather systems, are reviewed in this paper as well. Some research results have shown that the rainfall anomalies for different regions in China were closely related to the stages of El Nino events. 展开更多
关键词 tropical cyclones tropical meteorology research progress
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E-technology social support programs for autistic children: Can they work?
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作者 Natalie G Wall Oliver Smith +4 位作者 Linda E Campbell Carmel Loughland Mark Wallis Frans Henskens Ulrich Schall 《World Journal of Psychiatry》 SCIE 2021年第12期1239-1246,共8页
Autism is a neurodevelopmental condition with associated difficulties that present differently across individuals.One such difficulty is recognizing basic and complex facial expressions.Research has previously found t... Autism is a neurodevelopmental condition with associated difficulties that present differently across individuals.One such difficulty is recognizing basic and complex facial expressions.Research has previously found that there are many evidence-based support programs available for building non-verbal communication skills.These programs are frequently administered with a therapist or in a group setting,making them inflexible in nature.Programs hosted on e-technology are becoming increasingly popular,with many parents supportive of them.Applications(apps)that are hosted on technology such as iPads or mobile phones allow users to engage in building skills in real-time social settings and own what they are learning.These technologies are frequently used by autistic children,with apps typically focusing on identifying facial features.Yet at this current time,there are mixed reviews of how to design such programs and what their theoretical backing is,with many studies using a mix of observation and psychological assessments as outcome measures.Eye-tracking and electroencephalography are established methodologies that measure neural processing and gaze behaviors while viewing faces.To better support the field moving forward,objective measures such as these are a way to measure outcomes of apps that are designed for helping children on the spectrum build skills in understanding facial expressions. 展开更多
关键词 AUTISM Facial expression recognition TECHNOLOGY EYE-TRACKING Electroen-cephalography
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引入迷思概念的关键行动编码及其在过程数据诊断分类分析中的应用
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作者 詹沛达 高方方 陈琦鹏 《心理科学》 北大核心 2025年第2期485-503,共19页
迷思概念是指基于个人经验构建地对一些对象、事件或观点的错误理解,额外识别迷思概念有助于明确学生出现错误的具体原因。引入迷思概念的关键行动编码可实现基于过程数据对问题解决技能和迷思概念的联合诊断。通过实证例子阐述新编码... 迷思概念是指基于个人经验构建地对一些对象、事件或观点的错误理解,额外识别迷思概念有助于明确学生出现错误的具体原因。引入迷思概念的关键行动编码可实现基于过程数据对问题解决技能和迷思概念的联合诊断。通过实证例子阐述新编码方式在过程数据诊断分类分析中的应用与表现。结果发现:(1)引入迷思概念可实现对参与者的更精细分类,提供包含问题解决技能和迷思概念的综合诊断反馈;(2)迷思概念的掌握程度与任务最终表现呈中到高程度负相关。总之,新编码方式有助于研究者在过程数据分析中额外利用导致错误结果的问题解决过程所包含的信息,有助于更全面识别导致问题解决成败的具体原因,有益于实施有针对性干预。 展开更多
关键词 认知诊断 过程数据 问题解决 迷思概念 行动序列
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M-M滤波方法在GNSS/INS组合导航中的实用性分析 被引量:1
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作者 常国宾 叶陈旺 +2 位作者 唐琮淏 李京书 桑学凡 《中国惯性技术学报》 北大核心 2025年第4期340-349,共10页
全球导航卫星系统/惯性导航系统(GNSS/INS)组合导航的过程噪声和观测噪声受诸多因素影响,不可避免地呈现重尾非正态分布,缺乏抗差性的Kalman滤波因而会出现性能严重下降。针对此问题,分析了M-M滤波在GNSS/INS组合导航中的抗差实用性。首... 全球导航卫星系统/惯性导航系统(GNSS/INS)组合导航的过程噪声和观测噪声受诸多因素影响,不可避免地呈现重尾非正态分布,缺乏抗差性的Kalman滤波因而会出现性能严重下降。针对此问题,分析了M-M滤波在GNSS/INS组合导航中的抗差实用性。首先,基于M估计对Kalman滤波进行改进,建立M-M滤波模型。其次,分析了M-M滤波的抗差性。当满足小偏差假设且可以为M-M滤波提供较为合理的迭代初值时,M-M滤波的理论广义性在实用中是成立的。最后,对所提方法进行了仿真分析和实测实验验证。实验结果表明,相较于传统Kalman滤波方法,所提方法在北向和天向的定位均方根误差分别降低14.3%和17.1%。 展开更多
关键词 KALMAN滤波 重尾非正态分布 抗差M估计 M-M滤波
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水下航行器地形高程匹配算法研究综述 被引量:1
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作者 熊露 李京书 +1 位作者 饶喆 霍治帆 《水下无人系统学报》 2025年第1期1-14,共14页
水下航行器惯性导航误差随时间推移会不断累积,地形高程匹配技术以地形特征为定位依据,能够根据实测地形为惯性导航系统提供所需的持续位置修正信息,是国内外水下辅助导航领域的研究热点。文章以水下航行器地形匹配高程算法的发展为研... 水下航行器惯性导航误差随时间推移会不断累积,地形高程匹配技术以地形特征为定位依据,能够根据实测地形为惯性导航系统提供所需的持续位置修正信息,是国内外水下辅助导航领域的研究热点。文章以水下航行器地形匹配高程算法的发展为研究对象,首先指出当前水下航行器导航定位所面临的问题,在此基础上介绍了水下航行器地形匹配的基本原理及系统组成,并以水下地形匹配算法的发展为脉络,按序依次阐释了地形匹配算法发展中的主要阶段及典型算法的原理和优缺点;然后,分别介绍了国内外水下地形匹配算法的原理改进和试验应用情况;最后,简要总结国内外在水下地形匹配算法方面研究的侧重点,并结合并行计算、多波束声呐和水下地形特征分析三方面技术的发展,探讨了提高水下匹配算法性能的有效途径,可为本领域研究人员提供借鉴参考。 展开更多
关键词 水下航行器 地形辅助导航 地形高程 地形匹配算法
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原子重力仪动态测量系统中加速度计的现场标定
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作者 黄春福 闫久江 +3 位作者 李安 覃方君 车浩 龚文斌 《飞控与探测》 2025年第2期72-81,共10页
加速度计可用于原子重力仪的振动校正,抑制振动噪声的干扰,提高原子重力仪的动态测量精度,是测量系统中不可缺少的一部分。为了获得更高的器件精度,在使用前需对加速度计误差进行标定。结合原子重力仪动态测量系统,基于加速度计重力矢... 加速度计可用于原子重力仪的振动校正,抑制振动噪声的干扰,提高原子重力仪的动态测量精度,是测量系统中不可缺少的一部分。为了获得更高的器件精度,在使用前需对加速度计误差进行标定。结合原子重力仪动态测量系统,基于加速度计重力矢量模不变原则,将加速度计置于稳定平台多个姿态下测量,对比原子重力仪高精度重力输出,建立代价函数。为了避免迭代方法耗时长、对初始值依赖较大等问题,对代价函数进行简化,推导了线性模型,采用最小二乘方法计算零偏、标度因数和非正交系数等标定参数。开展仿真试验,探究加速度计噪声水平,加速度计姿态数量以及参数初始值对各标定方法的影响,初步证明了本文方法的有效性和精度优势。进一步开展码头系泊条件下的实测试验,结果表明,标定后加速度计输出矢量模的平均值从1.0035 g下降到1.0001 g,更接近重力加速度参考值g,且标准差下降了70.5%。 展开更多
关键词 加速度计 现场标定 原子重力仪 最小二乘法
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Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease
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作者 Ling-Xiao Yi Hui Ren Woon +3 位作者 Genevieve Saw Li Zeng Eng King Tan Zhi Dong Zhou 《Neural Regeneration Research》 SCIE CAS 2025年第11期3193-3206,共14页
The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative disease.Although the detailed patho... The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative disease.Although the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and therapy.The induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease therapies.The current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem cells.The benefits of induced pluripotent stem cell-based research are highlighted.Various dopaminergic neuron differentiation protocols from induced pluripotent stem cells are compared.The emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are evaluated.Finally,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease. 展开更多
关键词 dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches
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Amyloid-beta pathology-induced nanoscale synaptic disruption:the case of the GABA_B-GIRK assembly
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作者 Rafael Lujan Alejandro Martín-Belmonte +1 位作者 Sergi Ferré Francisco Ciruela 《Neural Regeneration Research》 SCIE CAS 2025年第5期1409-1410,共2页
Alzheimer's disease (AD) is characterized by an imbalance between excitatory and inhibitory brain networks,leading to aberrant homeostatic synaptic plasticity.AD has progressively been recognized as syna ptopathy ... Alzheimer's disease (AD) is characterized by an imbalance between excitatory and inhibitory brain networks,leading to aberrant homeostatic synaptic plasticity.AD has progressively been recognized as syna ptopathy and syna ptic dysfunction has been identified as a key component of its pathogenesis (Schirinzi et al.,2020).Syna ptic dysfunction is believed to precede synapse loss,a primary biological correlate of cognitive decline in AD,inevita bly associated with neuronal death. 展开更多
关键词 ALZHEIMER PATHOLOGY
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结直肠癌化疗期间营养状况变化轨迹与癌因性疲乏的关系
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作者 田杨 姚翠 《安徽医学》 2025年第10期1212-1217,共6页
目的 探讨结直肠癌患者化疗期间营养状况变化轨迹与癌因性疲乏的关系。方法 选取南京医科大学第一附属医院(江苏省人民医院)2023年1月至2024年8月收治的197例结直肠癌患者,采用主观整体营养状况评价表(PG-SGA)评估患者化疗前、化疗初期... 目的 探讨结直肠癌患者化疗期间营养状况变化轨迹与癌因性疲乏的关系。方法 选取南京医科大学第一附属医院(江苏省人民医院)2023年1月至2024年8月收治的197例结直肠癌患者,采用主观整体营养状况评价表(PG-SGA)评估患者化疗前、化疗初期、化疗中期、化疗后期营养状况,构建潜类别轨迹模型(LCTM)对营养状况变化轨迹进行分组,并于化疗后期,采用癌因性疲乏自评量表(CRF)评估患者癌因性疲乏症状,记录癌因性疲乏发生率,采用logistic回归分析营养状况变化轨迹与癌因性疲乏的关系。结果 最终有186例患者参与研究。结肠癌患者化疗前、化疗初期、化疗中期、化疗后期PG-SGA总分分别为(4.37±0.31)分、(4.38±0.30)分、(5.46±0.33)分、(6.50±0.42)分。经过LCTM筛选确定3个分类轨迹为最优模型,分别为低-稳定降低型组、中-缓慢升高型组、高-快速升高型组。3组年龄、TNM分期、分化程度、长期卧床、CRF总分及癌因性疲乏发生率比较,差异均有统计学意义(P<0.05)。调整年龄、TNM分期、分化程度、长期卧床后,中-缓慢升高型组、高-快速升高型组癌因性疲乏发生风险较低-稳定降低型组增加1.500倍、4.011倍(P<0.05),且癌因性疲乏发生风险随着PG-SGA总分升高而升高(χ^(2)趋势=146.728,P<0.05)。结论 结直肠癌患者化疗期间营养状况欠佳,随着化疗周期延长呈现恶化趋势,且与癌因性疲乏呈线性相关,需积极关注并开展营养支持。 展开更多
关键词 结直肠癌 化疗期间 营养状况 变化轨迹 癌因性疲乏
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The role of the unfolded protein response pathway in bone homeostasis and potential therapeutic target in cancer-associated bone disease
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作者 Moy E.Muehebach Sarah A.Hostein 《Bone Research》 2025年第5期1047-1064,共18页
The unfolded protein response pathway is an evolutionarily conserved cytoprotective signaling cascade,essential for cell function and survival.Unfolded protein response signaling is tightly integrated with bone cell d... The unfolded protein response pathway is an evolutionarily conserved cytoprotective signaling cascade,essential for cell function and survival.Unfolded protein response signaling is tightly integrated with bone cell differentiation and function,and chronic unfolded protein response activation has been identified in bone disease.The unfolded protein response has been found to promote oncogenesis and drug resistance,raising the possibility that unfolded protein response modulators may have activity as anti-cancer agents.Cancer-associated bone disease remains a major cause of morbidity for patients with multiple myeloma or bone-metastatic disease.Understanding the critical role of unfolded protein response signaling in cancer development and metastasis,as well as its role in bone homeostasis,may lead to novel mechanisms by which to target cancer-associated bone disease.In this review,we summarize the current research delineating the roles of the unfolded protein response in bone biology and pathophysiology,and furthermore,review unfolded protein response modulating agents in the contexts of cancer and cancer-associated bone disease. 展开更多
关键词 unfolded protein response protein response signaling unfolded protein response pathway bone homeostasis cancer associated bone disease cytoprotective signaling cascadeessential promote oncogenesis drug resistanceraising
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