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Vibration-induced bias error reduction using loop gain compensation for high-precision fiber optic gyroscopes
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作者 CHEN Heyu QIN Xuexin +2 位作者 XIE Huan KONG Linghai ZHENG Yue 《Journal of Systems Engineering and Electronics》 2025年第1期224-232,共9页
Vibration-induced bias deviation,which is generated by intensity fluctuations and additional phase differences,is one of the vital errors for fiber optic gyroscopes(FOGs)operating in vibration environment and has seve... Vibration-induced bias deviation,which is generated by intensity fluctuations and additional phase differences,is one of the vital errors for fiber optic gyroscopes(FOGs)operating in vibration environment and has severely restricted the applications of high-precision FOGs.The conventional methods for suppressing vibration-induced errors mostly concentrate on reinforcing the mechanical structure and optical path as well as the compensation under some specific operation parameters,which have very limited effects for high-precision FOGs maintaining performances under vibration.In this work,a technique of suppressing the vibration-induced bias deviation through removing the part related to the varying gain from the rotation-rate output is put forward.Particularly,the loop gain is extracted out by adding a gain-monitoring wave.By demodulating the loop gain and the rotation rate simultaneously under distinct frequencies and investigating their quantitative relationship,the vibrationinduced bias error is compensated without limiting the operating parameters or environments,like the applied modulation depth.The experimental results show that the proposed method has achieved the reduction of bias error from about 0.149°/h to0.014°/h during the random vibration with frequencies from20 Hz to 2000 Hz.This technique provides a feasible route for enhancing the performances of high-precision FOGs heading towards high environmental adaptability. 展开更多
关键词 vibration-induced error fiber optic gyroscope(FOG) loop gain
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Detection of co-phasing error in segmented mirror based on extended Young’s interferometry combined with Vision Transformer
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作者 LIU Yin-ling YAO Chi +3 位作者 OUYANG Shang-tao WAN Yi-rong CHEN Mo LI Bin 《中国光学(中英文)》 北大核心 2026年第1期205-218,共14页
Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the... Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the monolithic counterpart,the sub-mirrors must maintain precise co-phasing.Piston error critically degrades segmented mirror imaging quality,necessitating efficient and precise detection.To ad-dress the limitations that the conventional circular-aperture diffraction with two-wavelength algorithm is sus-ceptible to decentration errors,and the traditional convolutional neural networks(CNNs)struggle to capture global features under large-range piston errors due to their restricted local receptive fields,this paper pro-poses a method that integrates extended Young’s interference principles with a Vision Transformer(ViT)to detect piston error.By suppressing decentration error interference through two symmetrically arranged aper-tures and extending the measurement range to±7.95μm via a two-wavelength(589 nm/600 nm)algorithm.This approach exploits ViT’s self-attention mechanism to model global characteristics of interference fringes.Unlike CNNs constrained by local convolutional kernels,the ViT significantly improves sensitivity to inter-ferogram periodicity.The simulation results demonstrate that the proposed method achieves a measurement accuracy of 5 nm(0.0083λ0)across the range of±7.95μm,while maintaining an accuracy exceeding 95%in the presence of Gaussian noise(SNR≥15 dB),Poisson noise(λ≥9 photons/pixel),and sub-mirror gap er-ror(Egap≤0.2)interference.Moreover,the detection speed shows significant improvement compared to the cross-correlation algorithm.This study establishes an accurate,robust framework for segmented mirror error detection,advancing high-precision astronomical observation. 展开更多
关键词 segmented mirror co-phasing piston errors ViT Young’s interference principles
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Reshaping“Cerebellar Inhibition”:Mechanistic Insights and Precision Medicine Perspectives for rTMS in Machado-Joseph Disease
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作者 HAN Ya-Zhen ZHOU Jie +2 位作者 CHEN Yu-Chao GAO Zhong-Ming CHE Xian-Wei 《生物化学与生物物理进展》 北大核心 2026年第2期505-510,共6页
Machado-Joseph disease,or spinocerebellar ataxia type 3(SCA3),represents the most common autosomal dominant cerebellar ataxia worldwide.Despite its progressive and debilitating nature,disease-modifying therapies remai... Machado-Joseph disease,or spinocerebellar ataxia type 3(SCA3),represents the most common autosomal dominant cerebellar ataxia worldwide.Despite its progressive and debilitating nature,disease-modifying therapies remain elusive.Repetitive transcranial magnetic stimulation(rTMS)has emerged as a promising non-invasive intervention;however,its clinical application has been hindered by inconsistent protocols and a lack of mechanistic understanding.A recent landmark study published in Brain Stimulation by Chen et al.addressed these challenges by combining a high-dose intermittent theta-burst stimulation(iTBS)protocol with concurrent transcranial magnetic stimulation-electroencephalography(TMS-EEG).This commentary provides an in-depth analysis of their findings,highlighting the restoration of cerebello-cortical inhibition(CBI)as a key therapeutic mechanism.Furthermore,we discuss the broader implications of this work,proposing that future translational research should integrate accelerated iTBS(aiTBS)paradigms,cortical response measurements(CRM),and individualized neuro-navigation to establish a new era of precision neuromodulation for ataxia. 展开更多
关键词 Machado-Joseph disease(spinocerebellar ataxia type 3 SCA3) transcranial magnetic stimulationelectroencephalography(TMS-EEG) cerebello-cortical inhibition NEUROMODULATION precision medicine
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Forecast errors of tropical cyclone track and intensity by the China Meteorological Administration from 2013 to 2022
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作者 Huanmujin Yuan Hong Wang +2 位作者 Yubin Li Kevin K.W.Cheung Zhiqiu Gao 《Atmospheric and Oceanic Science Letters》 2026年第1期72-77,共6页
This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administratio... This study presents a comprehensive evaluation of tropical cyclone(TC)forecast performance in the western North Pacific from 2013 to 2022,based on operational forecasts issued by the China Meteorological Administration.The analysis reveals systematic improvements in both track and intensity forecasts over the decade,with distinct error characteristics observed across various forecast parameters.Track forecast errors have steadily decreased,particularly for longer lead times,while error magnitudes have increased with longer forecast lead times.Intensity forecasts show similar progressive enhancements,with maximum sustained wind speed errors decreasing by 0.26 m/s per year for 120 h forecasts.The study also identifies several key patterns in forecast performance:typhoon-grade or stronger TCs exhibit smaller track errors than week or weaker systems;intensity forecasts systematically overestimate weaker TCs while underestimating stronger systems;and spatial error distributions show greater track inaccuracies near landmasses and regional intensity biases.These findings highlight both the significant advances in TC forecasting capability achieved through improved modeling and observational systems,and the remaining challenges in predicting TC changes and landfall behavior,providing valuable benchmarks for future forecast system development. 展开更多
关键词 Forecast error Tropical cyclone TRACK INTENSITY
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A Preliminary Study on Controlling Chilo suppressalis in Rice Fields Using Precision Timing and Insecticide Combinations
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作者 Li Wang Jinfeng Zhang +3 位作者 Binbin Li Zhengbo Pen Zhiyuan Yang Anshu Rastogi 《Phyton-International Journal of Experimental Botany》 2026年第2期155-165,共11页
Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population in... Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population investigation and dynamic monitoring of C.suppressalis populations were conducted in the Meishan region of Sichuan,China,from 2023 to 2024.The optimal timing for insecticide application was estimated,followed by field trials evaluating the efficacy of different insecticides.Results demonstrated that the peak emergence of first-generation adults typically occurred in early July(under the environmental conditions of the Meishan region),with the ambient humidity below 75%and temperature around 29◦C.Pesticide efficacy trials show that insecticide combinations exhibited superior control.Notably,a combined treatment of emamectin benzoate⋅methoxyfenozide+chlorantraniliprole achieved the highest control efficacy(90.05%)and a corresponding yield of 12,491.55 kg/ha.All tested treatments were determined to be safe for rice growth.Furthermore,this optimized strategy resulted in notable economic benefits,including a 50%reduction in pesticide usage and cost savings of 4796.15 CNY compared to conventional practices.This study provides valuable insights into sustainable rice production and pest management and,for the first time,proposes a precision application time window based on intelligent monitoring. 展开更多
关键词 Chilo suppressalis RICE precision timing emamectin benzoate CHLORANTRANILIPROLE
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Artificial intelligence and machine learning-driven advancements in gastrointestinal cancer:Paving the way for precision medicine
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作者 Chahat Suri Yashwant K Ratre +2 位作者 Babita Pande LVKS Bhaskar Henu K Verma 《World Journal of Gastroenterology》 2026年第1期14-36,共23页
Gastrointestinal(GI)cancers remain a leading cause of cancer-related morbidity and mortality worldwide.Artificial intelligence(AI),particularly machine learning and deep learning(DL),has shown promise in enhancing can... Gastrointestinal(GI)cancers remain a leading cause of cancer-related morbidity and mortality worldwide.Artificial intelligence(AI),particularly machine learning and deep learning(DL),has shown promise in enhancing cancer detection,diagnosis,and prognostication.A narrative review of literature published from January 2015 to march 2025 was conducted using PubMed,Web of Science,and Scopus.Search terms included"gastrointestinal cancer","artificial intelligence","machine learning","deep learning","radiomics","multimodal detection"and"predictive modeling".Studies were included if they focused on clinically relevant AI applications in GI oncology.AI algorithms for GI cancer detection have achieved high performance across imaging modalities,with endoscopic DL systems reporting accuracies of 85%-97%for polyp detection and segmentation.Radiomics-based models have predicted molecular biomarkers such as programmed cell death ligand 2 expression with area under the curves up to 0.92.Large language models applied to radiology reports demonstrated diagnostic accuracy comparable to junior radiologists(78.9%vs 80.0%),though without incremental value when combined with human interpretation.Multimodal AI approaches integrating imaging,pathology,and clinical data show emerging potential for precision oncology.AI in GI oncology has reached clinically relevant accuracy levels in multiple diagnostic tasks,with multimodal approaches and predictive biomarker modeling offering new opportunities for personalized care.However,broader validation,integration into clinical workflows,and attention to ethical,legal,and social implications remain critical for widespread adoption. 展开更多
关键词 Artificial intelligence Gastrointestinal cancer precision medicine Multimodal detection Machine learning
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Total score of the computer vision syndrome questionnaire predicts refractive errors and binocular vision anomalies
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作者 Mosaad Alhassan Tasneem Samman +5 位作者 Hatoun Badukhen Muhamad Alrashed Balsam Alabdulkader Essam Almutleb Tahani Alqahtani Ali Almustanyir 《International Journal of Ophthalmology(English edition)》 2026年第1期90-96,共7页
AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A... AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A total of 141 healthy computer users underwent comprehensive clinical visual function assessments,including evaluations of refractive errors,accommodation(amplitude of accommodation,positive relative accommodation,negative relative accommodation,accommodative accuracy,and accommodative facility),and vergence(phoria,positive and negative fusional vergence,near point of convergence,and vergence facility).Total CVS-Q scores were recorded to explore potential associations between symptom scores and the aforementioned clinical visual function parameters.RESULTS:The cohort included 54 males(38.3%)with a mean age of 23.9±0.58y and 87 age-matched females(61.7%)with a mean age of 23.9±0.53y.The multiple regression model was statistically significant[R²=0.60,F=13.28,degrees of freedom(DF=17122,P<0.001].This indicates that 60%of the variance in total CVS-Q scores(reflecting reported symptoms)could be explained by four clinical measurements:amplitude of accommodation,positive relative accommodation,exophoria at distance and near,and positive fusional vergence at near.CONCLUSION:The total CVS-Q score is a valid and reliable tool for predicting the presence of various nonstrabismic binocular vision anomalies and refractive errors in symptomatic computer users. 展开更多
关键词 computer vision syndrome refractive errors ACCOMMODATION VERGENCE binocular vision SYMPTOMS
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Engineering revolution of cell membrane-biomimetic nanoparticles:from hybridization strategy innovation to microfluidics-enabled precision fabrication
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作者 Qi Liu Yang Liu +3 位作者 Li Qiao Shiqi Chang Xiafeng Peng Ning-Ping Huang 《Science China Materials》 2026年第3期1369-1393,共25页
With the continuous advancement of bionanomaterial technology,the design and fabrication strategies of biomimetic nanocarriers have undergone significant strategic transformations and innovations.This article systemat... With the continuous advancement of bionanomaterial technology,the design and fabrication strategies of biomimetic nanocarriers have undergone significant strategic transformations and innovations.This article systematically reviews the evolution from single-cell membrane nanovesicles to hybrid cell membrane nanovesicles integrating multiple cell membranes,culminating in cell membrane hybrid lipid nanoparticles(CM-LNPs)combining natural cell membranes or membrane proteins with engineered synthetic phospholipids.This technological progression enables the synergistic retention of multicellular biological functions and the incorporation of advantageous synthetic material properties,such as enhanced engineering flexibility and surface modifiability.Additionally,the article discusses the advantages and limitations of traditional extrusion and ultrasonication methods in the preparation of cell membrane nanovesicles,highlights the benefits and development prospects of novel microfluidic techniques in the preparation of CM-LNPs,and explores the future application prospects and challenges of CM-LNPs in the biomedical field. 展开更多
关键词 cell membrane hybrid lipid nanoparticles BIONANOTECHNOLOGY drug delivery system MICROFLUIDICS precision medicine
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Rateless Polar Codes with Unequal Error Protection Property
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作者 Cui Chen Xiang Wei +1 位作者 Ma Siwei Guo Qing 《China Communications》 2026年第1期10-23,共14页
Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a prom... Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a promising solution due to their outstanding error-correction performance and low complexity.Unequal error protection(UEP)involves nonuniform error safeguarding for distinct data segments,achieving a fine balance between error resilience and resource allocation,which ultimately enhancing system performance and efficiency.In this paper,we propose a novel class of UEP rateless polar codes.The codes are designed based on matrix extension of polar codes,and elegant mapping and duplication operations are designed to achieve UEP property while preserving the overall performance of conventional polar codes.Superior UEP performance is attained without significant modifications to conventional polar codes,making it straightforward for compatibility with existing polar codes.A theoretical analysis is conducted on the block error rate and throughput efficiency performance.To the best of our knowledge,this work provides the first theoretical performance analysis of UEP rateless polar codes.Simulation results show that the proposed codes significantly outperform existing polar coding schemes in both block error rate and throughput efficiency. 展开更多
关键词 matrix extension polar codes rateless coding unequal error protection
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Retaining local chemical effects:An error cancellation strategy for calculating standard gas-phase enthalpy of formation
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作者 Rui Liu Chaoyang Zhang +2 位作者 Linyuan Wang Zhiyu Huang Jian Liu 《Defence Technology(防务技术)》 2026年第1期172-179,共8页
Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches m... Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches may be ineffective for systems with strong localized chemical effects,as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them.To address this issue,we propose the Substructure-Preserved Connection-Based Hierarchy(SCBH),a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation.The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules.Therein,based on the atomization scheme,the reference and test values are derived at the levels of Gaussian-4(G4)and M062X/6-31+G(2df,p),respectively.Compared to commonly used approaches,SCBH reduces the average computational error by half and requires only15%of the computational cost of G4 to achieve comparable accuracy.Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation,substituents with strong electronic effects should be retained preferentially.SCBH can be readily extended to diverse classes of organic compounds.Its workflow and source code allow flexible customization of molecular moieties,including azide,carboxyl,trinitromethyl,phenyl,and others.This strategy facilitates accurate,rapid,and automated computations and corrections,making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation. 展开更多
关键词 Gas-phase enthalpy of formation error cancellation Quantum chemical High throughput
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AI-driven integration of multi-omics and multimodal data for precision medicine
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作者 Heng-Rui Liu 《Medical Data Mining》 2026年第1期1-2,共2页
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ... High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1). 展开更多
关键词 high throughput transcriptomics multi omics single cell multimodal learning frameworks foundation models omics data modalitiesemerging ai driven precision medicine
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OPTIMAL POINT-WISE ERROR ESTIMATE OF TWO SECOND-ORDER ACCURATE FINITE DIFFERENCE SCHEMES FOR THE HEAT EQUATION WITH CONCENTRATED CAPACITY
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作者 Leilei Shi Tingchun Wang Xuanxuan Zhou 《Journal of Computational Mathematics》 2026年第1期61-83,共23页
In this paper,we propose and analyze two second-order accurate finite difference schemes for the one-dimensional heat equation with concentrated capacity on a computa-tional domain=[a,b].We first transform the target ... In this paper,we propose and analyze two second-order accurate finite difference schemes for the one-dimensional heat equation with concentrated capacity on a computa-tional domain=[a,b].We first transform the target equation into the standard heat equation on the domain excluding the singular point equipped with an inner interface matching(IIM)condition on the singular point x=ξ∈(a,b),then adopt Taylor’s ex-pansion to approximate the IIM condition at the singular point and apply second-order finite difference method to approximate the standard heat equation at the nonsingular points.This discrete procedure allows us to choose different grid sizes to partition the two sub-domains[a,ξ]and[ξ,b],which ensures that x=ξ is a grid point,and hence the pro-posed schemes can be generalized to the heat equation with more than one concentrated capacities.We prove that the two proposed schemes are uniquely solvable.And through in-depth analysis of the local truncation errors,we rigorously prove that the two schemes are second-order accurate both in temporal and spatial directions in the maximum norm without any constraint on the grid ratio.Numerical experiments are carried out to verify our theoretical conclusions. 展开更多
关键词 Heat equation with concentrated capacity Finite difference scheme Inner interface matching condition Unconditional convergence Optimal error estimate
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Lighting the way:precision doping in organic semiconductors
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作者 Niansheng Xu Feng Gao 《Science China Materials》 2026年第3期1797-1798,共2页
Doping is essential for modulating semiconductor conductivity,forming p-n junctions,and reducing contact resistance[1].Notably,as organic semiconductors(OSCs)advance toward high performance,flexibility,and miniaturiza... Doping is essential for modulating semiconductor conductivity,forming p-n junctions,and reducing contact resistance[1].Notably,as organic semiconductors(OSCs)advance toward high performance,flexibility,and miniaturization,achieving precise regionally selective doping becomes critical for building complex,highly integrated devices[2].In inorganic semiconductors(e.g.,silicon),sub-100-nanometer regional doping is achievable through photolithography and ion implantation—techniques foundational to modern complementary metaloxide-semiconductor(CMOS)technology[3]. 展开更多
关键词 reducing contact resistance notablyas organic semiconductors oscs advance precision ion implantation techniques inorganic semiconductors egsilicon sub nanometer regionally selective doping LIGHTING modulating semiconductor conductivityforming
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Acute liver failure caused by amino acid or organic acid related inborn errors of metabolism
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作者 Ying Zhou Chi Chen Xin Yang 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期112-114,共3页
Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].... Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5]. 展开更多
关键词 biochemical pathway toxic intermediates metabolic diseases early acute liver failure inborn errors metabolism iems organic acid dysfunction distinct enzyme metabolic processestherefore metabolic pathways
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Perioperative management of pediatric patients with inborn errors of metabolism during liver transplantation
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作者 Susan Paulin Akila Rajakumar +2 位作者 Jagadeesh Menon Naresh Shanmugam Mohamed Rela 《World Journal of Transplantation》 2026年第1期91-102,共12页
Inborn errors of metabolism(IEM)are rare disorders,most are liver-based with liver transplantation(LT)emerging as an effective cure in the pediatric population.LT has been shown to offer a cure or deter disease progre... Inborn errors of metabolism(IEM)are rare disorders,most are liver-based with liver transplantation(LT)emerging as an effective cure in the pediatric population.LT has been shown to offer a cure or deter disease progression and provide symptomatic improvement in patients with IEM.Each metabolic disorder is unique,with the missing enzyme or transporter protein causing substrate deficiency or toxic byproduct production.Knowledge about the distribution of deficient enzymes,the percentage of enzymes replaced by LT,and the extent of extrahepatic involvement helps anticipate and manage complications in the perioperative period.Most patients have multisystem involvement and can be on complex dietary regimens.Metabolic decompensation can be triggered due to the stress response to surgery,fasting and other unanticipated complications perioperatively.Thus,a multidisciplinary team’s input including those from metabolic specialists is essential to develop disease and patient-specific strategies for the perioperative management of these patients during LT.In this review,we outline the classification of IEM,indications for LT along with potential benefits,basic metabolic defects and their implications,details of extrahepatic involvement and perioperative management strategies for LT in children with some of the commonly presenting IEM,to assist anesthesiologists handling this cohort of patients. 展开更多
关键词 Inborn errors of metabolism Anaesthesia for paediatric liver transplantation Metabolic crisis Hyperammonemia in paediatric liver transplantation Perioperative care in metabolic liver diseases
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Harnessing CD146-positive mesenchymal stromal cells for precision therapy in acute respiratory distress syndrome
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作者 Özlem Tomsuk 《World Journal of Stem Cells》 2026年第1期1-7,共7页
Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal ce... Acute respiratory distress syndrome(ARDS)is a life-threatening condition that is characterized by high mortality rates and limited therapeutic options.Notably,Zhang et al demonstrated that CD146+mesenchymal stromal cells(MSCs)exhibited greater therapeutic efficacy than CD146-MSCs.These cells enhance epithelial repair through nuclear factor kappa B/cyclooxygenase-2-associated paracrine signaling and secretion of pro-angiogenic factors.We concur that MSCs hold significant promise for ARDS treatment;however,the heterogeneity of cell products is a translational barrier.Phenotype-aware strategies,such as CD146 enrichment,standardized potency assays,and extracellular vesicle profiling,are essential for improving the consistency of these studies.Further-more,advanced preclinical models,such as lung-on-a-chip systems,may provide more predictive insights into the therapeutic mechanisms.This article underscores the importance of CD146+MSCs in ARDS,emphasizes the need for precision in defining cell products,and discusses how integrating subset selection into translational pipelines could enhance the clinical impact of MSC-based therapies. 展开更多
关键词 Acute respiratory distress syndrome Mesenchymal stromal cells CD146 Nuclear factor kappa B/cyclooxygenase-2 signaling pathway Extracellular vesicles Endothelial barrier repair precision medicine
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Temperature Variable Optimization for Precision Machine Tool Thermal Error Compensation on Optimal Threshold 被引量:11
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作者 ZHANG Ting YE Wenhua +2 位作者 LIANG Ruijun LOU Peihuang YANG Xiaolan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期158-165,共8页
Machine tool thermal error is an important reason for poor machining accuracy. Thermal error compensation is a primary technology in accuracy control. To build thermal error model, temperature variables are needed to ... Machine tool thermal error is an important reason for poor machining accuracy. Thermal error compensation is a primary technology in accuracy control. To build thermal error model, temperature variables are needed to be divided into several groups on an appropriate threshold. Currently, group threshold value is mainly determined by researchers experience. Few studies focus on group threshold in temperature variable grouping. Since the threshold is important in error compensation, this paper arms to find out an optimal threshold to realize temperature variable optimization in thermal error modeling. Firstly, correlation coefficient is used to express membership grade of temperature variables, and the theory of fuzzy transitive closure is applied to obtain relational matrix of temperature variables. Concepts as compact degree and separable degree are introduced. Then evaluation model of temperature variable clustering is built. The optimal threshold and the best temperature variable clustering can be obtained by setting the maximum value of evaluation model as the objective. Finally, correlation coefficients between temperature variables and thermal error are calculated in order to find out optimum temperature variables for thermal error modeling. An experiment is conducted on a precise horizontal machining center. In experiment, three displacement sensors are used to measure spindle thermal error and twenty-nine temperature sensors are utilized to detect the machining center temperature. Experimental result shows that the new method of temperature variable optimization on optimal threshold successfully worked out a best threshold value interval and chose seven temperature variables from twenty-nine temperature measuring points. The model residual of z direction is within 3 μm. Obviously, the proposed new variable optimization method has simple computing process and good modeling accuracy, which is quite fit for thermal error compensation. 展开更多
关键词 precision machine tool thermal error cluster analysis
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Precision Design for Machine Tool Based on Error Prediction 被引量:5
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作者 HUANG Qiang ZHANG Genbao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期151-157,共7页
Digitization precision analysis is an important tool to ensure the design precision of machine tool currently. The correlative research about precision modeling and analysis mainly focuses on the geometry precision an... Digitization precision analysis is an important tool to ensure the design precision of machine tool currently. The correlative research about precision modeling and analysis mainly focuses on the geometry precision and motion precision of machine tool, and the forming motion precision of workpiece surface. For the machine tool with complex forming motion, there is not accurate corresponding relationship between the existing criterion on precision design and the machining precision of workpiece. Therefore, a design scheme on machine tool precision based on error prediction is proposed, which is divided into two-stage digitization precision analysis crucially. The first stage aims at the technology system to complete the precision distribution and inspection from the workpiece to various component parts of technology system and achieve the total output precision of machine tool under the specified machining precision; the second stage aims at the machine tool system to complete the precision distribution and inspection from the output precision of machine tool to the machine tool components. This article serves YK3610 gear hobber as the example to describe the error model of two systems and basic application method, and the practical cutting precision of this machine tool achieves to 5-4-4 grade. The proposed method can provide reliable guidance to the precision design of machine tool with complex forming motion. 展开更多
关键词 complex forming motion machine tool precision design position-pose error error sensibility
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Profile error compensation in precision grinding of ellipsoid optical surface 被引量:4
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作者 Shimeng YU Jiahao ZHU +1 位作者 Peng YAO Chuanzhen HUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第4期115-123,共9页
Optical glass elements with the ellipsoidal surface are used in many critical aerospace instruments,such as satellites,telescope and cameras.Their optical performance is mainly affected by profile accuracy and surface... Optical glass elements with the ellipsoidal surface are used in many critical aerospace instruments,such as satellites,telescope and cameras.Their optical performance is mainly affected by profile accuracy and surface quality.In this paper,a rectangular ellipsoid surface is precisely ground on a BK7 optical glass blank by grating scanning grinding path with a three-axis CNC precision surface grinder.A profile error compensation procedure for ellipsoidal grinding is proposed based on the error analysis about the primary error sources in the XY and YZ projection planes during the grinding process.The mathematical prediction models of the wheel arc profile error,the measurement and wear error of the grinding wheel radiuses are established.By applying the proposed error compensation procedure,the profile accuracy of the ellipsoidal surface was improved from 4 lm to 2 lm in the XY plane,and improved from 15 lm to 5 lm in the YZ plane. 展开更多
关键词 Aspheric lens Ellipsoid surface error compensation Grinding wheel truing precision grinding
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Analysis and Application of Multiple-Precision Computation and Round-off Error for Nonlinear Dynamical Systems 被引量:4
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作者 王鹏飞 黄刚 王在志 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第5期758-766,共9页
This research reveals the dependency of floating point computation in nonlinear dynamical systems on machine precision and step-size by applying a multiple-precision approach in the Lorenz nonlinear equations. The pap... This research reveals the dependency of floating point computation in nonlinear dynamical systems on machine precision and step-size by applying a multiple-precision approach in the Lorenz nonlinear equations. The paper also demoastrates the procedures for obtaining a real numerical solution in the Lorenz system with long-time integration and a new multiple-precision-based approach used to identify the maximum effective computation time (MECT) and optimal step-size (OS). In addition, the authors introduce how to analyze round-off error in a long-time integration in some typical cases of nonlinear systems and present its approximate estimate expression. 展开更多
关键词 multiple-precision numerical calculation round-off error nonlinear dynamical system
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