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A Novel Roll Compensation Method for Two-Axis Transportable Satellite Antennas 被引量:3
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作者 Laiding Zhao Jidong Xie +1 位作者 Xiaodong Bai Zhicheng Qu 《China Communications》 SCIE CSCD 2018年第3期137-148,共12页
Two-axis transportable satellite antennas(TATSAs) have been widely adopted owing to its simple structure and low cost. However, by searching in a wide range, it will take a very long searching time. Under extreme cond... Two-axis transportable satellite antennas(TATSAs) have been widely adopted owing to its simple structure and low cost. However, by searching in a wide range, it will take a very long searching time. Under extreme conditions, it will even fail to work. In this paper, we propose a novel roll compensation(RC) method for the low-cost TATSAs to achieve faster tracking even if when the antenna has no azimuth sensor. By analyzing the influence of roll axis on the system performance, details of the compensation method are derived. Simulation and measurement results indicate that the proposed RC method can effectively reduce the initial searching time for satellite communication. In addition, tracking along with the ellipse path with the RC method provides the highest tracking efficiency. 展开更多
关键词 two-axis transportable satelliteantenna (TATSA) satellite tracking roll com-pensation (RC) searching time.
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Transportable 1555-nm Ultra-Stable Laser with Sub-0.185-Hz Linewidth 被引量:8
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作者 Zhao-Yang Tai Lu-Lu Yan +4 位作者 Yan-Yan Zhang Xiao-Fei Zhang Wen-Ge Guo Shou-Gang Zhang Hai-Feng Jiang 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第9期33-36,共4页
We present two cavity-stabilized lasers at 1555 nm, which are built to be the frequency source for a transportable photonic microwave generation system. The frequency instability reaches the thermal noise limit (7 &#... We present two cavity-stabilized lasers at 1555 nm, which are built to be the frequency source for a transportable photonic microwave generation system. The frequency instability reaches the thermal noise limit (7 ×10-16) of the 10-cm ultra-low expansion glass cavity at 1-10s averaging time and the beat signal of the two lasers reveals a remarkable linewidth of 185mHz. 展开更多
关键词 transportable 1555-nm Ultra-Stable Laser with Sub-0.185-Hz Linewidth
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Laboratory demonstration of geopotential measurement using transportable optical clocks 被引量:1
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作者 刘道信 曹健 +6 位作者 袁金波 崔凯枫 袁易 张平 晁思嘉 舒华林 黄学人 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期272-277,共6页
We report an experimental demonstration of geopotential difference measurement using a pair of transportable ^(40)Ca^(+) optical clocks(TOC-729-1 and TOC-729-3)in the laboratory,each of them has an uncertainty of 1.3&... We report an experimental demonstration of geopotential difference measurement using a pair of transportable ^(40)Ca^(+) optical clocks(TOC-729-1 and TOC-729-3)in the laboratory,each of them has an uncertainty of 1.3×10^(−17) and an instability of 4.8×10^(−15)/√τ.Referenced to a stationary clock of TOC-729-1,the geopotential difference measurements are realized by moving TOC-729-3 to three different locations and the relevant altitude differences are measured with uncertainties at the level of 20 cm.After correcting the systematic shifts(including gravitational red shift),the two-clock frequency difference is measured to be–0.7(2.2)×10^(−17),considering both the statistic(1.0×10^(−17))and the systematic(1.9×10^(−17))uncertainties.The frequency difference between these two clocks is within their respective uncertainties,verifying the reliability of transportable ^(40)Ca^(+) optical clocks at the low level of 10^(−17). 展开更多
关键词 geopotential difference measurement transportable optical clock repeatability evaluation of clocks
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Transportable Identity Construction in Single Mother Family
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作者 徐嗣群 《海外英语》 2020年第20期123-124,共2页
This paper studies single-parent family conversation mainly,the researcher takes 10 hours of recordings in a single-parent family in Shenzhen as data to study conversational identity construction.
关键词 transportable identity single mother identity construction
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Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion 被引量:2
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作者 Zhao Shi Yan Xu +2 位作者 Dunjian Xie Shiwei Xie Amer M.Y.M.Ghias 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2024年第1期189-201,共13页
This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle... This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted lines.Considering the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and RCs.To efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient solution.The effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system. 展开更多
关键词 Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program
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Optimization of temperature characteristics of a transportable 87Rb atomic fountain clock 被引量:2
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作者 Xinwen Wang Kangkang Liu +13 位作者 Henan Cheng Wei Ren Jingfeng Xiang Jingwei Ji Xiangkai Peng Zhen Zhang Jianbo Zhao Meifeng Ye Lin Li Tang Li Bin Wang Qiuzhi Qu Liang Liu Desheng Lü 《Chinese Optics Letters》 SCIE EI CAS CSCD 2019年第8期1-5,共5页
A high-performance transportable fountain clockis attractive for use in laboratories with high-precisiontime-frequency measurement requirements. This Letterreports the improvement of the stability of atransportable ru... A high-performance transportable fountain clockis attractive for use in laboratories with high-precisiontime-frequency measurement requirements. This Letterreports the improvement of the stability of atransportable rubidium-87 fountain clock because of anoptimization of temperature characteristics. This clockintegrates its physical packaging, optical benches,microwave frequency synthesizers, and electronic controlsonto an easily movable wheeled plate. Two optical bencheswith a high-vibration resistance are realized in thiswork. No additional adjustment is required after movingthem several times. The Allan deviation of the fountainclock frequency was measured by comparing it with that ofthe hydrogen maser. The fountain clock got a short-termstability of 2.3×10^-13 at 1 s and long-term stabilityon the order of 10-16 at 100,000 s. 展开更多
关键词 transportable clockis anoptimization
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Dietary micromineral proteinates improve mineral utilization by regulating transport and homeostatic proteins in pigs
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作者 Chao-Yue Ge Chen-Hao Zou +8 位作者 Yu-Jie Lv Wei-Chen Huang Shen-Ao Zhan Xin-Yu Shen Xiao-Xu Wang Hong-Meng Yuan Gang Lin Dong-You Yu Bing Liu 《Life Research》 2026年第1期61-72,共12页
Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,wi... Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,with limited data on the synergistic effects and molecular mechanisms of combined OTMs(Fe,Cu,Mn,Zn)in growing-finishing pigs.Methods:This study aimed to investigate the effects of graded levels of micromineral proteinates(combined OTMs)on growth performance,mineral metabolism,and mRNA expression of mineral regulatory proteins.A total of 360 crossbred Duroc×Landrace×Large White pigs(initial body weight 47.1±4.8 kg)were randomly assigned to 6 dietary treatments:basal diet without microminerals(CON),basal diet with ITMs at commercially recommended levels(IT),and basal diets with 15%(OT 15%),25%(OT 25%),35%(OT 35%)commercially recommended levels(CRL)of combined micromineral proteinates.After a 70-day feeding trial,samples were analyzed using ICP-OES,ELISA,and RT-qPCR.Results:Results showed that reduced levels(15-35%CRL)of micromineral proteinates did not significantly affect average daily gain,average daily feed intake,or feed conversion ratio(gain-to-feed ratio)compared to IT(P>0.05),but significantly increased plasma Cu(1.73-1.83μg/mL)and Zn(1.72-1.97μg/mL)concentrations(P<0.05)and elevated activities of Cu/Zn-superoxide dismutase(32.9-35.9 U/L)and manganese superoxide dismutase(20.5-24.1 U/L)compared to CON(P<0.05),with no significant differences from IT(P>0.05).Fecal excretion of Fe,Cu,Mn,and Zn was significantly reduced by 35-50%in OT 15%-OT 35%groups compared to IT(P<0.05).OT 25%group exhibited the highest apparent absorptivity of Fe(38.5%),Cu(27.8%),and Zn(42.4%)(P<0.05),which was associated with significantly regulated mRNA expression of mineral regulatory proteins:upregulated DMT1,FPN1,ZIP4,and MT1A in the duodenum,and modulated HAMP,ATP7B,ZIP14,and ZnT1 in the liver(P<0.05).Conclusion:In conclusion,dietary supplementation with 25%CRL or less of combined micromineral proteinates can fully meet the nutritional needs of growing-finishing pigs,improve mineral absorptivity,and reduce fecal mineral excretion by regulating intestinal and hepatic mineral transport and homeostatic proteins,providing a sustainable alternative to high-dose ITMs. 展开更多
关键词 trace mineral proteinates apparent absorptivity mineral transporters homeostatic proteins PIGS
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Decadal shift in Northeast China’s precipitation around 2000
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作者 Yawen Liao Tianbao Zhao +1 位作者 Jingpeng Zhang Yankun Sun 《Atmospheric and Oceanic Science Letters》 2026年第1期14-21,共8页
Northeast China(NEC),a critical agricultural and ecological zone,has experienced intensified hydrological variability under global warming,with cascading impacts on food security and ecosystem resilience.This study ut... Northeast China(NEC),a critical agricultural and ecological zone,has experienced intensified hydrological variability under global warming,with cascading impacts on food security and ecosystem resilience.This study utilized observational data and two new generation reanalysis products(i.e.,the fifth major global reanalysis produced by ECMWF(ERA5)and the Japanese Reanalysis for Three Quarters of a Century(JRA-3Q))to investigate the shift changes in precipitation in NEC around 2000 and associated water vapor transport.The analysis identified a pivotal interdecadal shift in 1998/99,transitioning from moderate increases(17.5 mm/10 yr during 1980-1998)to accelerated but more variable precipitation growth(85.4 mm/10 yr post-1999).While the mean precipitation during the post-shift period decreased,enhanced anticyclonic circulation amplified moisture divergence over continental NEC,redirecting vapor flux toward coastal regions.Crucially,trajectory analysis demonstrated regime-dependent moisture sourcing:midlatitude westerlies dominated during wet extremes(44% of trajectories in 1998),whereas East Asian monsoon flows prevailed in drought years(36% of trajectories in 2007).The post-1998 period exhibited increased reliance on localized recycling(45%of mid-tropospheric trajectories),reflecting weakened monsoonal inflow.These findings highlight NEC’s growing vulnerability to competing moisture pathways and atmospheric blocking-a dual mechanism that explains rising extremes despite declining mean precipitation.By reconciling dataset discrepancies(ERA5 vs.JRA-3Q trends)and elucidating circulation-precipitation linkages,this work provides actionable insights for climate-resilient agriculture in NEC’s water-stressed ecosystems. 展开更多
关键词 PRECIPITATION Decadal shift Water vapor transport Northeast China
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ABCA5 lipid transporter is associated with a reduced risk of Parkinson’s disease
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作者 Jasmin Galper Nicolas Dzamko Woojin Scott Kim 《Neural Regeneration Research》 2026年第2期669-670,共2页
A key pathological feature of Parkinson’s disease(PD)is that lysosomes are overwhelmed with cellular materials that need to be degraded and cleared.While the build-up of protein is characteristic of neurodegenerative... A key pathological feature of Parkinson’s disease(PD)is that lysosomes are overwhelmed with cellular materials that need to be degraded and cleared.While the build-up of protein is characteristic of neurodegenerative diseases such as PD and Alzheimer’s disease(AD)and is thought to reflect lysosome dysfunction,lipid accumulation may also contribute to and be indicative of severe lysosomal dysfunction.Much is known about the detrimental effects of glucosylceramide accumulation in PD lysosomes. 展开更多
关键词 neurodegenerative diseases lipid transporter abca LYSOSOME protein build up Alzheimers disease cellular materials Parkinsons disease
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Conversion of infected pine wood into energy charcoal material based on a transportable carbonization system
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作者 Liangmeng Ni Qi Gao +3 位作者 Hao Ren Mengfu Su Shaowen Rong Zhijia Liu 《Biochar》 CSCD 2024年第1期894-910,共17页
To prevent the spread of pine wilt disease(PWD),a transportable carbonization equipment was designed for in-situ treatment of infected pine wood(IPW).The equipment killed all pine wood nematodes(PWNs)in IPW when carbo... To prevent the spread of pine wilt disease(PWD),a transportable carbonization equipment was designed for in-situ treatment of infected pine wood(IPW).The equipment killed all pine wood nematodes(PWNs)in IPW when carbonization temperature was up to 200℃.The optimal laboratory process of infected pine wood charcoal(IPWC)was carbonization temperature of 500℃,heating rate of 3℃min^(−1)and holding time of 0 min.Based on the optimal laboratory process,the transportable carbonization equipment produced IPWC with a fixed carbon content of 79.82%,and ash content of 1.14%and a moisture content of 7.83%,which meets the requirements of EN 1860-2:2005(E)standard.The economic efficiency of incineration(T1 mode),crushing(T2 mode),and transportable carbonization(T3 mode)was evaluated.For each ton of IPW treatment,the profit generated was−75.48 USD in T1 mode,26.28 USD in T2 mode,and 51.91 USD in T3 mode.T3 mode had the highest economic efficiency.These findings will be helpful to provide guidance for the control of PWD and value-added utilization of IPW. 展开更多
关键词 Pine nematode Masson pine transportable carbonization equipment Smoke treatment system Energy properties Economic efficiency
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Stress granules:Guardians of cellular health and triggers of disease
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作者 Meghal Desai Keya Gulati +2 位作者 Manasi Agrawal Shruti Ghumra Pabitra K.Sahoo 《Neural Regeneration Research》 2026年第2期588-597,共10页
Stress granules are membraneless organelles that serve as a protective cellular response to external stressors by sequestering non-translating messenger RNAs(mRNAs)and regulating protein synthesis.Stress granules form... Stress granules are membraneless organelles that serve as a protective cellular response to external stressors by sequestering non-translating messenger RNAs(mRNAs)and regulating protein synthesis.Stress granules formation mechanism is conserved across species,from yeast to mammals,and they play a critical role in minimizing cellular damage during stress.Composed of heterogeneous ribonucleoprotein complexes,stress granules are enriched not only in mRNAs but also in noncoding RNAs and various proteins,including translation initiation factors and RNA-binding proteins.Genetic mutations affecting stress granule assembly and disassembly can lead to abnormal stress granule accumulation,contributing to the progression of several diseases.Recent research indicates that stress granule dynamics are pivotal in determining their physiological and pathological functions,with acute stress granule formation offering protection and chronic stress granule accumulation being detrimental.This review focuses on the multifaceted roles of stress granules under diverse physiological conditions,such as regulation of mRNA transport,mRNA translation,apoptosis,germ cell development,phase separation processes that govern stress granule formation,and their emerging implications in pathophysiological scenarios,such as viral infections,cancer,neurodevelopmental disorders,neurodegeneration,and neuronal trauma. 展开更多
关键词 apoptosis axon regeneration biomolecular condensates germline cell development mRNA transport NEURODEGENERATION NEURODEVELOPMENT PATHOPHYSIOLOGY physiological functions stress granules translation viral infection
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Lactate and lactylation modifications in neurological disorders
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作者 Yu Gu Keyang Chen +5 位作者 Chunyan Lei Xinglong Yang Lu Wang Linhu Zhao Wen Jiang Qionghua Deng 《Neural Regeneration Research》 2026年第5期1681-1697,共17页
Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein ... Research into lactylation modifications across various target organs in both health and disease has gained significant attention.Many essential life processes and the onset of diseases are not only related to protein abundance but are also primarily regulated by various post-translational protein modifications.Lactate,once considered merely a byproduct of anaerobic metabolism,has emerged as a crucial energy substrate and signaling molecule involved in both physiological and pathological processes within the nervous system.Furthermore,recent studies have emphasized the significant role of lactate in numerous neurological diseases,including Alzheimer's disease,Parkinson's disease,acute cerebral ischemic stroke,multiple sclerosis,Huntington's disease,and myasthenia gravis.The purpose of this review is to synthesize the current research on lactate and lactylation modifications in neurological diseases,aiming to clarify their mechanisms of action and identify potential therapeutic targets.As such,this work provides an overview of the metabolic regulatory roles of lactate in various disorders,emphasizing its involvement in the regulation of brain function.Additionally,the specific mechanisms of brain lactate metabolism are discussed,suggesting the unique roles of lactate in modulating brain function.As a critical aspect of lactate function,lactylation modifications,including both histone and non-histone lactylation,are explored,with an emphasis on recent advancements in identifying the key regulatory enzymes of such modifications,such as lactylation writers and erasers.The effects and specific mechanisms of abnormal lactate metabolism in diverse neurological diseases are summarized,revealing that lactate acts as a signaling molecule in the regulation of brain functions and that abnormal lactate metabolism is implicated in the progression of various neurological disorders.Future research should focus on further elucidating the molecular mechanisms underlying lactate and lactylation modifications and exploring their potential as therapeutic targets for neurological diseases. 展开更多
关键词 astrocyte-neuron lactate shuttle theory brain functions brain lactate metabolism central nervous system histone lysine lactylation monocarboxylate transporters nervous system neurodegenerative diseases non-histone lysine lactylation post-translational modifications
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A Hybrid Approach for Pavement Crack Detection Using Mask R-CNN and Vision Transformer Model 被引量:2
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作者 Shorouq Alshawabkeh Li Wu +2 位作者 Daojun Dong Yao Cheng Liping Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期561-577,共17页
Detecting pavement cracks is critical for road safety and infrastructure management.Traditional methods,relying on manual inspection and basic image processing,are time-consuming and prone to errors.Recent deep-learni... Detecting pavement cracks is critical for road safety and infrastructure management.Traditional methods,relying on manual inspection and basic image processing,are time-consuming and prone to errors.Recent deep-learning(DL)methods automate crack detection,but many still struggle with variable crack patterns and environmental conditions.This study aims to address these limitations by introducing the Masker Transformer,a novel hybrid deep learning model that integrates the precise localization capabilities of Mask Region-based Convolutional Neural Network(Mask R-CNN)with the global contextual awareness of Vision Transformer(ViT).The research focuses on leveraging the strengths of both architectures to enhance segmentation accuracy and adaptability across different pavement conditions.We evaluated the performance of theMaskerTransformer against other state-of-theartmodels such asU-Net,TransformerU-Net(TransUNet),U-NetTransformer(UNETr),SwinU-NetTransformer(Swin-UNETr),You Only Look Once version 8(YoloV8),and Mask R-CNN using two benchmark datasets:Crack500 and DeepCrack.The findings reveal that the MaskerTransformer significantly outperforms the existing models,achieving the highest Dice SimilarityCoefficient(DSC),precision,recall,and F1-Score across both datasets.Specifically,the model attained a DSC of 80.04%on Crack500 and 91.37%on DeepCrack,demonstrating superior segmentation accuracy and reliability.The high precision and recall rates further substantiate its effectiveness in real-world applications,suggesting that the Masker Transformer can serve as a robust tool for automated pavement crack detection,potentially replacing more traditional methods. 展开更多
关键词 Pavement crack segmentation TRANSPORTATION deep learning vision transformer Mask R-CNN image segmentation
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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism 被引量:1
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作者 Yujie Yang Xinyi Li +7 位作者 Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo 《Neural Regeneration Research》 SCIE CAS 2025年第1期93-106,共14页
Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.... Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders. 展开更多
关键词 aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease PARKINSONISM positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2
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Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease 被引量:1
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作者 Olivier Kerdiles Méryl-Farelle Oye Mintsa Mi-mba +8 位作者 Katherine Coulombe Cyntia Tremblay VincentÉmond Martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon 《Neural Regeneration Research》 SCIE CAS 2025年第2期574-586,共13页
There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 poly... There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic pathway.First,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal denervation.Four weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 weeks.During this period,the animals had access to a running wheel,which they could use or not.Docosahexaenoic acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars compacta.However,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned striatum.Compared to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned striatum.The present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease. 展开更多
关键词 6-HYDROXYDOPAMINE DOPAMINE dopamine transporter EXERCISE neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3
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基于入口压力调控的二冷气-水喷嘴内部流场特性解析
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作者 何鑫 王慧胜 +5 位作者 崔贺楠 张江山 陈林恒 李明 管敏 刘青 《钢铁》 北大核心 2025年第11期112-122,共11页
喷淋冷却是连铸二冷区的主要冷却方式,喷嘴射流行为直接影响喷淋冷却效果,进而影响连铸坯质量。以某钢厂方坯连铸用气-水扇形喷嘴为研究对象,构建了喷嘴射流仿真模型,探究了喷嘴入口处气、水压力变化对喷嘴内部流体速度、湍动能和涡分... 喷淋冷却是连铸二冷区的主要冷却方式,喷嘴射流行为直接影响喷淋冷却效果,进而影响连铸坯质量。以某钢厂方坯连铸用气-水扇形喷嘴为研究对象,构建了喷嘴射流仿真模型,探究了喷嘴入口处气、水压力变化对喷嘴内部流体速度、湍动能和涡分布的影响规律,揭示了影响喷嘴出口处水流量稳定性的关键因素,提出了相应的调控方法。结果表明,当水压以0.10 MPa的梯度从0.10 MPa增加到0.30 MPa时,液相初始速度逐渐增大,其值分别为2.43、5.45和9.17 m/s;喷嘴内部液相最大速度位置距喷嘴水入口的距离分别为35、29和25 mm,相应的气-液两相速度梯度逐渐降低;液相黏性力增加,湍动能平均值降低,其值分别为367.66、142.43和96.87 m^(2)/s^(2);喷嘴内中心大涡逐渐减小,喷嘴内壁附近的小涡逐渐消失;喷嘴出口水流量变异系数从0.533分别降低至0.505和0.489,有利于改善喷嘴出口流量稳定性。当气压以0.05 MPa的梯度从0.10 MPa增加至0.20 MPa时,液相初始速度先降低后升高,其变化幅度分别为2.44、1.22 m/s;喷嘴内液相最大速度位置保持不变,液相最大速度先升高1.59 m/s,而后降低1.85 m/s;湍动能平均值逐渐增大,其值分别为165.21、367.66和598.90 m^(2)/s^(2);喷嘴内中心大涡扩张或分裂为多个中等涡群,小涡数量增加并向中心迁移;喷嘴出口水流量变异系数从0.514提高至0.533和0.575,喷嘴出口流量稳定性降低。当水压为0.30 MPa、气压为0.10 MPa时,喷嘴出口流量稳定性最佳,可为连铸二次冷却工艺调控提供理论和数据支撑。 展开更多
关键词 连铸 二次冷却 气-水喷嘴 内部流场 出口流量稳定性 数值模拟 VOF(volume of fluid)模型 SST(shear-stress transport)k-ω模型
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Renal glucosuria in children 被引量:2
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作者 Meral Torun Bayram Salih Kavukcu 《World Journal of Clinical Pediatrics》 2025年第1期46-54,共9页
The kidneys play a critical role in maintaining glucose homeostasis.Under normal renal tubular function,most of the glucose filtered from the glomeruli is re-absorbed in the proximal tubules,leaving only trace amounts... The kidneys play a critical role in maintaining glucose homeostasis.Under normal renal tubular function,most of the glucose filtered from the glomeruli is re-absorbed in the proximal tubules,leaving only trace amounts in the urine.Glycosuria can occur as a symptom of generalized proximal tubular dysfunction or when the reabsorption threshold is exceeded or the glucose threshold is reduced,as seen in familial renal glycosuria(FRG).FRG is characterized by persistent glycosuria despite normal blood glucose levels and tubular function and is primarily associated with mutations in the sodium/glucose cotransporter 5A2 gene,which encodes the sodium-glucose cotransporter(SGLT)2.Inhibiting SGLTs has been proposed as a novel treatment strategy for diabetes,and since FRG is often considered an asymptomatic and benign condition,it has inspired preclinical and clinical studies using SGLT2 inhibitors in type 2 diabetes.However,patients with FRG may exhibit clinical features such as lower body weight or height,altered systemic blood pressure,diaper dermatitis,amino-aciduria,decreased serum uric acid levels,and hypercalciuria.Further research is needed to fully understand the pathophysiology,molecular genetics,and clinical manifestations of renal glucosuria. 展开更多
关键词 Sodium-glucose cotransporters Basolateral glucose transporters Familial renal glucosuria Intestinal glucose-galactose malabsorption Fanconi-Bickel syndrome Sodium-glucose cotransporter 2 inhibitors
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Particle transport in fractured geo-energy reservoirs considering the effect of fluid inertia and turbulent flow:A review 被引量:2
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作者 E.A.A.V.Edirisinghe M.S.A.Perera +2 位作者 D.Elsworth S.K.Matthai E.Goudeli 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1906-1939,共34页
Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and... Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and gas extraction.Central to this phenomenon is the transport of proppants,tiny solid particles injected into the fractures to prevent them from closing once the injection is stopped.However,effective transport and deposition of proppant is critical in keeping fracture pathways open,especially in lowpermeability reservoirs.This review explores,then quantifies,the important role of fluid inertia and turbulent flows in governing proppant transport.While traditional models predominantly assume and then characterise flow as laminar,this may not accurately capture the complexities inherent in realworld hydraulic fracturing and proppant emplacement.Recent investigations highlight the paramount importance of fluid inertia,especially at the high Reynolds numbers typically associated with fracturing operations.Fluid inertia,often overlooked,introduces crucial forces that influence particle settling velocities,particle-particle interactions,and the eventual deposition of proppants within fractures.With their inherent eddies and transient and chaotic nature,turbulent flows introduce additional complexities to proppant transport,crucially altering proppant settling velocities and dispersion patterns.The following comprehensive survey of experimental,numerical,and analytical studies elucidates controls on the intricate dynamics of proppant transport under fluid inertia and turbulence-towards providing a holistic understanding of the current state-of-the-art,guiding future research directions,and optimising hydraulic fracturing practices. 展开更多
关键词 Two-phase flows Rock fractures Proppant transport Fluid inertia Turbulent flows Hydraulic fracturing
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Enhanced lymphatic transportation of SLN by mimicking oligopeptide transportation route 被引量:1
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作者 Fuya Jia Xiaoxing Fan +6 位作者 Licheng Wu Yating Wang Jisen Zhang Zhou Zhou Lian Li Jingyuan Wen Yuan Huang 《Asian Journal of Pharmaceutical Sciences》 2025年第3期141-153,共13页
Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen so... Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen source for nourishment.They are mainly transported by oligopeptide transporter-1(PepT-1)which are primarily expressed in the intestine with the characteristics of high-capacity and low energy consumption.Our preliminary research discovered the transmembrane transport of SLN could be improved by stimulating the oligopeptide absorption pathway.This implied the potential of combining the advantages of SLN with oligopeptide transporter mediated transportation.Herein,two kinds of dipeptide modified SLN were designed with insulin and glucagon like peptide-1(GLP-1)analogue exenatide as model drugs.These drugs loaded SLN showed enhanced oral bioavailability and hypoglycemic effect in both type I diabetic C57BL/6mice and type II diabetic KKAymice.Compared with un-modified SLN,dipeptide-modified SLN could be internalized by intestinal epithelial cells via PepT-1-mediated endocytosis with higher uptake.Interestingly,after internalization,more SLN could access the systemic circulation via lymphatic transport pathway,highlighting the potential to combine the oligopeptide-absorption route with SLN for oral drug delivery. 展开更多
关键词 Oral delivery Protein and peptide drugs Solid lipid nanoparticles Lymphatic transportation Oligopeptide transportation
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Karst Trough Control of Solute Transport Processes at Two Karst Groundwater Flow Systems,Western Hubei,Central China 被引量:1
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作者 Yi'an Wang Ruichao Zhao +6 位作者 Lin Ding Shuai Xiong Yin Li Jianwei Bu Wei Chen Hong Zhou Wei Liu 《Journal of Earth Science》 2025年第4期1731-1741,共11页
To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migong... To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migongquan(MGQ))in Sixi valley,western Hubei,China.Highresolution continuous monitoring was utilized to obtain breakthrough curves(BTCs),which were then analyzed using the multi-dispersion model(MDM)and the two-region nonequilibrium model(2RNE)with basic parameters calculated by CXTFIT and QTRACER2.Results showed that:(1)YQD flow system had a complex infiltration matrix with overland flow,conduit flow and fracture flow,while the MGQ flow system was dominated by conduit flow with fast flow transport velocity,but also small amount of fracture flow there;(2)They were well fitted based on the MDM(R^2=0.928)and 2RNE(R^2=0.947)models,indicating that they had strong adaptability in the karst trough zone;(3)conceptual models for YQD and MGQ groundwater systems were generalized.In YQD system,the solute was transported via overland flow during intense rainfall,while some infiltrated down into fissures and conduits.In MGQ system,most were directly transported to spring outlet in the fissureconduit network. 展开更多
关键词 Central China conceptual model karst trough zone multi-dispersion model and two-region nonequilibrium model solute transport processes tracer tests solute transport groundwater flow
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