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Revision of the absolute configurations of Pallavicinia diterpenoids and further discovery of their Diels-Alder cycloadducts 认领 引用
1
作者 Jiao-Zhen Zhang Cheng-Min Zhang +7 位作者 Yong-Jie Wang Pei-Lin Wu Rui-Feng Liu Ye Li Ming-Zhu Zhu Shuang-Zhi Yuan Ze-Jun Xu Hong-Xiang Lou 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第1期394-398,共5页
Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is c... Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is crucial for the confirmation of absolute configurations.Ignoring critical parameters will lead to false structure,which may confuse the total synthesis and drug development.Herein,the configurations of seven heterogeneous Pallavicinia diterpenoids(PDs) isolated from Pallavicinia liverworts are revised using a combination of single-crystal X-ray diffraction and electronic circular dichroism(ECD) calculations.Meanwhile,identification of five unprecedented PD heterodimers PD-dimers A-E(18-22) along with eleven previously undescribed PDs(5-9,13-17,23) obtained by the reinvestigation of the Chinese liverwort Pallavicinia subciliata have resulted in corrections and support the revised conclusions. 展开更多
关键词 Revision Absolute configurations Pallavicinia diterpenoids Liverwort Single-crystal X-ray diffraction Electronic circular dichroism calculations
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Absolute Quantification of Aging-Associated Glycans in IgG for Biological Age Prediction:Insights from Glycomics and Transcriptomics 认领 引用
2
作者 Huijuan Zhao Jiteng Fan +7 位作者 Jing Han Wenjun Qin Jichen Sha Weilong Zhang Yong Gu Xiaonan Ma Jianxin Gu Shifang Ren 《Engineering》 SCIE EI CSCD 2026年第2期113-125,共13页
Immunoglobulin G(IgG)N-glycans are associated with aging.In this study,we introduce a novel strategy for discovering aging-associated IgG glycans and establish a prediction model on the basis of their absolute concent... Immunoglobulin G(IgG)N-glycans are associated with aging.In this study,we introduce a novel strategy for discovering aging-associated IgG glycans and establish a prediction model on the basis of their absolute concentration alterations.We employed glycomic quantification technology to identify alterations in the amount of IgG glycan in natural aging and antiaging(caloric restriction(CR))models and discovered aging-related glycans.The glycomic analysis revealed key features:downregulation of the bisected glycan GP3(F(6)A2B)and upregulation of the digalactosylated glycan GP8(F(6)A2G2).These glycan changes showed significant fold changes from an early stage.Using external standards of these two glycans,we subsequently measured their absolute concentrations,allowing for us to establish a predictive model,abGlycoAge,for biological aging.The abGlycoAge index suggested a younger state under CR,with an average age reduction of 3.9–14.0 weeks.Additionally,RNA sequencing of splenic B cells revealed that Derl3,Smarcb1,Ankrd55,Tbkbp1,and Slc38a10 may contribute to alterations in GP3 and GP8 during the aging process.In a preliminary therapeutic study,we tested IgG modified with young signature Nglycans(IgG-Ny).High-dose IgG-Ny showed promising results,alleviating aging-related physiological declines,including reductions in inflammatory markers and improvements in organ senescence,particularly in the brain,kidney,and lungs.This research provides new insights into glycan changes during aging and lays the groundwork for potential antiaging therapies.GP3 and GP8 may serve as biomarkers for aging,offering new perspectives on aging mechanisms and therapeutic approaches. 展开更多
关键词 Absolute quantification Immunoglobulin G N-glycome Aging Glycan biomarker
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Active vibration isolation based on absolute-relative dynamic stiffness control via multi-sensor information fusion 认领 引用
3
作者 Zhiwei Huang Jiulin Wu +4 位作者 Fuxiang Zhang Rui Zhou Hu Li Xuedong Chen Wei Jiang 《ENGINEERING Mechanical Engineering》 SCIE CAS CSCD 2026年第2期129-152,共24页
The requirements for isolating outer vibration and suppressing inner disturbances are increasingly stringent and even approaching extreme limits in integrated circuit manufacturing,precision measurement,scientific exp... The requirements for isolating outer vibration and suppressing inner disturbances are increasingly stringent and even approaching extreme limits in integrated circuit manufacturing,precision measurement,scientific experiments,etc.In comparison with passive isolation,active control methods can significantly enhance vibration isolation performance.However,different control strategies are mainly effective in different frequency domains,and performance may deteriorate in some frequency domains due to sensor noises.Active vibration isolation based on absolute-relative dynamic stiffness control via multi-sensor information fusion is proposed in this paper.This method can substantially improve vibration attenuation capability and position stability performances in broad bandwidth,with a particular focus on improving the resonance peak suppression capability in the ultra-low frequency domain.First,the effects of different control strategies on vibration isolation in different frequency domains are analyzed,and the hybrid control strategy is proposed by using both absolute relative signal feedback.Considering the noise characteristics of absolute velocity sensors and relative displacement sensors,different filters are accordingly adopted to improve vibration isolation performance.A one-dimensional experimental platform is established to conduct vibration control experiments under different configurations.The results demonstrate that vibration isolation performance across a wide frequency range can be significantly improved,and the proposed method further proves effective for micro-vibration systems.Typically,transmissibility can be reduced to as low as -30 dB at 1 Hz and -48 dB at 2 Hz,with guarantee of less than -50 dB within 10-50 Hz.Additionally,compliance results show 10-40 dB performance improvements across the broad frequency range(0.1-100 Hz)compared with the passive system. 展开更多
关键词 active vibration control dynamic stiffness multi-sensor information fusion absolute velocity feedback relative displacement feedback
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Research on the absolute measurement of air kerma in superficial X‑ray radiotherapy 认领 引用
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作者 Jun‑Xia Bao Rui Zhao +3 位作者 Xiao Zhang Jin‑Jie Wu Wei‑Cheng Ding Mao‑Yuan Chang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第8期38-49,共12页
Scar formation results from nonregenerative healing after tissue injury.Complications may occur if the scar grows beyond a certain threshold.Superficial X-ray radiotherapy offers significant advantages as an adjuvant ... Scar formation results from nonregenerative healing after tissue injury.Complications may occur if the scar grows beyond a certain threshold.Superficial X-ray radiotherapy offers significant advantages as an adjuvant method for surgical treatment of scars.Following the widespread application of the superficial X-ray radiotherapy system SRT-100,accurate dose measurements are key to the implementation of superficial X-ray radiotherapy.In this study,the absorbed dose measured in superficial X-ray radiotherapy was traced to the primary standard based on air kerma.According to this principle,based on the technical parameters of the SRT-100 system,this study establishes the corresponding reference radiation qualities by relying on an industrial X-ray tube and uses a free-air ionization chamber to obtain the corresponding correction factors through experiments and simulations to realize absolute air kerma measurements and uncertainty evaluations.In this context,air kerma calibration and associated uncertainty evaluations were performed for the parallel-plate transfer ionization chambers PTW23342 and PTW23344.The results show that the mean energies of the fluence spectra simulated at the X-ray tube voltages of 50,70,and 100 kV were 26.2,34.1,and 44.7 keV,respectively.The measured results of the first half-value layer at the three tube voltages were 0.538,1.146,and 2.190 mmAl.The air kerma of three radiation qualities were 1.487,1.436,and 1.268 mGy/s.The expanded measurement uncertainty of air kerma by the free-air ionization chamber was 0.94%(k=2),and the expanded uncertainties of the calibration factor in the two transfer ionization chambers were 1.00%(k=2)and 0.96%(k=2). 展开更多
关键词 Superficial X-ray radiotherapy Air kerma Correction factor Absolute measurement Uncertainty
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Suppression of initial value changes in the dual transponder carrier ranging system for absolute distance measurement 认领 引用
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作者 Tao ZHANG Ziru LI +1 位作者 Zhaobin XU Zhonghe JIN 《ENGINEERING Information Technology & Electronic Engineering》 SCIE EI CSCD 2026年第6期105-116,共12页
The dual transponder carrier ranging system,an enhancement over the dual one-way ranging system,provides highprecision relative distance measurements without imposing stringent time synchronization requirements.Howeve... The dual transponder carrier ranging system,an enhancement over the dual one-way ranging system,provides highprecision relative distance measurements without imposing stringent time synchronization requirements.However,a critical limitation to its use in absolute distance measurement is the initial value change phenomenon,which manifests as abrupt phase changes after every system restart.Through theoretical analysis,the root causes of this phenomenon are identified as a fractional output-to-input frequency ratio in the frequency synthesizer and a non-integer coherent turnaround ratio.To validate the theoretical analysis,simulations are conducted using Simulink,and experimental verification is performed on an S-band and C-band hardware platform.Both simulation and experimental results demonstrate that configuring both ratios as integers effectively suppresses these abrupt phase changes.These findings establish an integer-ratio design rule that is independent of specific frequency plans,providing a general design guideline for coherent transponder ranging systems intended for absolute distance measurement,as well as a reference for frequency planning in other absolute distance measurement systems of the same kind. 展开更多
关键词 Dual transponder Carrier phase ranging Absolute distance measurement Initial value change
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New-onset diabetes and pancreatic cancer:Current evidence on absolute risk and screening feasibility 认领 引用
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作者 Seoung Hoon Kim 《World Journal of Gastrointestinal Oncology》 SCIE 2026年第7期36-42,共7页
Pancreatic ductal adenocarcinoma(PDAC)remains a highly lethal malignancy largely due to delayed diagnosis,prompting growing interest in early clinical signals that may facilitate earlier detection.New-onset diabetes(N... Pancreatic ductal adenocarcinoma(PDAC)remains a highly lethal malignancy largely due to delayed diagnosis,prompting growing interest in early clinical signals that may facilitate earlier detection.New-onset diabetes(NOD)has emerged as one such signal,supported by accumulating epidemiologic evidence demonstrating a temporal association between diabetes onset and subsequent PDAC diagnosis.Recent large population-based studies have confirmed an increased relative risk of PDAC among individuals with glycemically defined NOD,particularly within the first few years after diabetes onset.However,despite this association,the absolute incidence of PDAC in NOD populations remains low,raising critical questions regarding the feasibility and clinical justification of population-wide screening strategies.This discrepancy between relative risk elevation and absolute event probability represents a central challenge in translating epidemiologic findings into actionable clinical practice.Risk stratification models,such as the Enriching NOD for Pancreatic Cancer score,have been proposed to address this gap,yet their real-world performance highlights persistent limitations when applied as stand-alone tools for diagnostic decision-making.This minireview synthesizes recent epidemiologic,modeling,and screening-related evidence to clarify the clinical role of NOD in PDAC detection.Current evidence supports viewing NOD as a gatekeeper for stepwise risk enrichment rather than a screening indication and favors risk-enriched,stepwise diagnostic strategies,with future work focused on prospective validation,integrated biomarkers,and actionable absolute-risk thresholds. 展开更多
关键词 Pancreatic cancer New-onset diabetes Risk stratification Absolute risk Early detection
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Preliminary study on a quantification method and standardization for aquatic microbial loads based on microbial diversity absolute quantitative sequencing 认领 引用 被引量：1
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作者 Wen Li Jing Libin +4 位作者 Li Xiawei Lu Jing Jin Haowei Yang Yongqi Li Xueling 《China Standardization》 2026年第1期68-73,共6页
This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from... This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R2>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration. 展开更多
关键词 absolute quantification microbial load 16S rRNA sequencing spike-in standardization aquatic microbes
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A preliminary study on microbial load quantification method and standardization in fermented foods based on microbial diversity absolute quantitative sequencing:A case study of Inner Mongolia traditional fermented vegetables(lanyancai) 认领 引用
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作者 Xiawei Duan Bin +1 位作者 Lu Jing Yang Yongqi 《China Standardization》 2026年第3期60-65,共6页
Traditional fermented vegetables(lanyancai)in Inner Mongolia are culturally significant fermented foods characterized by intricate microbial communities.However,the empirical traditional production methodologies frequ... Traditional fermented vegetables(lanyancai)in Inner Mongolia are culturally significant fermented foods characterized by intricate microbial communities.However,the empirical traditional production methodologies frequently result in inconsistent product quality.Conventional high-throughput sequencing approaches,which generate relative abundance data,are inherently limited in their capacity to reflect absolute microbial biomass dynamics.This limitation obscures the distinction between quality deterioration attributable to“microbial community succession”and that driven by“total biomass over-accumulation.”To address this methodological gap,this study implemented the Absolute Quantitative Microbiome Profiling(aQMP),utilizing a spike-in normalization strategy to establish a metrological framework for microbial load quantification within this high-salt and high-acid fermented matrix.The data demonstrated the robust stability of this method,enabling precise quantification of total microbial load.Notably,while lactic acid bacteria maintained a dominant relative abundance throughout the process,samples exhibiting quality defects displayed a significant escalation in total microbial load-increasing approximately tenfold compared to samples at the standard fermentation stage.These findings suggest that product quality decline is primarily due to the uncontrolled proliferation of the total microbial biomass rather than the dominance of specific spoilage organisms.This study provides a scientific foundation for the standardized production and quality control of traditional fermented foods through absolute microbial quantification. 展开更多
关键词 absolute quantification microbial load spike-in normalization traditional fermented vegetables quality control standardization
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ENGINet:End-to-end deep learning of the cumulative absolute velocity,Arias intensity,and spectrum intensity prediction for on-site earthquake early warning 认领 引用 被引量：3
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作者 Zhu Jingbao Li Shanyou Song Jindong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2025年第4期943-957,I0002-I0096,共15页
One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(IA),and spectrum intensity(SI)are ... One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(IA),and spectrum intensity(SI)are important parameters for measuring ground motion intensity and assessing earthquake damage.Due to the limited available information in EEW,CAV,IA,and SI cannot be accurately predicted using traditional EEW methods.In this paper,we propose an end-to-end deep learning-based Ground motion Intensity prediction Network(ENGINet)for on-site EEW.The aim of the ENGINet is to predict CAV,IA,and SI rapidly and reliably.ENGINet is based on a convolutional neural network and recurrent neural network.The inputs of the network are three-component acceleration records,three-component velocity records,and three-component displacement records obtained by a single station.The results from the test dataset show that at 3 s after the P-wave arrival,compared with the baseline models and other traditional methods,ENGINet has better performance in predicting CAV,IA,and SI.Our results indicate that ENGINet can quickly and accurately predict CAV,IA,and SI to some extent and has good potential in EEW efforts. 展开更多
关键词 on-site earthquake early warning deep learning cumulative absolute velocity arias intensity spectrum intensity
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Absolutely Clean N-Complexes 认领 引用
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作者 HAN Xia WANG Xin LU Bo 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2025年第2期133-138,共6页
The notion of absolutely clean N-complexes is studied.We show that an N-complex X is absolutely clean if and only if X is Nexact and Z,(X)is an absolutely clean module for each n e Z and i=1,2,..,N.In particular,we pr... The notion of absolutely clean N-complexes is studied.We show that an N-complex X is absolutely clean if and only if X is Nexact and Z,(X)is an absolutely clean module for each n e Z and i=1,2,..,N.In particular,we prove that a bounded above N-complex X is absolutely clean if and only if X,is an absolutely clean module for each n e Z.We also show that under certain hypotheses,an Ncomplex X is Gorenstein AC-injective if and only if Z;(X)is a Gorenstein AC-injective module for each n e Z and t=1,2,.,N. 展开更多
关键词 absolutely clean module absolutely clean N-complex Gorenstein AC-injective N-complex
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Digital PCR-free technologies for absolute quantitation of nucleic acids at single-molecule level 认领 引用
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作者 Xinyi Luo Ke Wang +3 位作者 Yingying Xue Xiaobao Cao Jianhua Zhou Jiasi Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第2期90-98,共9页
Ultrasensitive detection of nucleic acids is of great significance for precision medicine.Digital polymerase chain reaction(dPCR)is the most sensitive method but requires sophisticated and expensive instruments and a ... Ultrasensitive detection of nucleic acids is of great significance for precision medicine.Digital polymerase chain reaction(dPCR)is the most sensitive method but requires sophisticated and expensive instruments and a long reaction time.Digital PCR-free technologies,which mean the digital assay not relying on thermal cycling to amplify the signal for quantitative detection of nucleic acids at the singlemolecule level,include the digital isothermal amplification techniques(d IATs)and the digital clustered regularly interspaced short palindromic repeats(CRISPR)technologies.They combine the advantages of d PCR and IATs,which could be fast and simple,enabling absolute quantification of nucleic acids at a single-molecule level with minimum instrument,representing the next-generation molecular diagnostic technology.Herein,we systematically summarized the strategies and applications of various dIATs,including the digital loop-mediated isothermal amplification(dLAMP),the digital recombinase polymerase amplification(dRPA),the digital rolling circle amplification(dRCA),the digital nucleic acid sequencebased amplification(d NASBA)and the digital multiple displacement amplification(d MDA),and evaluated the pros and cons of each method.The emerging digital CRISPR technologies,including the detection mechanism of CRISPR and the various strategies for signal amplification,are also introduced comprehensively in this review.The current challenges as well as the future perspectives of the digital PCR-free technology were discussed. 展开更多
关键词 Digital bioassay Isothermal amplification Nucleic acid detection Digital CRISPR Cas Absolute quantification
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A high-throughput measurement of critical micelle concentrations based on absolute aggregation-caused quenching probes 认领 引用
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作者 Xin Ji Aun Raza +3 位作者 Jianping Qi Yi Lu Haisheng He Wei Wu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2025年第3期651-653,共3页
Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous ... Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous fluorimetry-based probes have been developed to measure CMCs[3](Fig.S1).However,CMC measurements using these probes suffer from a time-consuming and laborious procedure and large uncertainties,primarily due to their poor photo-stabilities and highly fluctuating fluorescence backgrounds. 展开更多
关键词 high throughput measurement photo stabilities fluorescence backgrounds critical micelle concentration cmc numerous materials science critical micelle concentration fluorimetry based probes absolute aggregation caused quenching
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Absolute Cross Sections for Direct and Dissociative Ionizations of Oxygen Molecule Measured by 350-8000 eV Electron Impact 认领 引用
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作者 Weizhe Huang Taj Wali Khan +3 位作者 Yuting Zhang Enliang Wang Xu Shan Xiangjun Chen 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2025年第2期164-171,I0039,共8页
The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O2^... The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O22+,O22+O+,O2+,and their total)and two Coulomb explosion channels(O++O+and O2++O+)are obtained by putting the data of O2+on the scale of Ar+from O2and Ar gases mixed with a fixed relative flow ratio of 1:1.The experimental errors are assessed by taking uncertainties of various factors into account.The present absolute cross sections are well consistent with the previous data in the overlapped energy range below 1000 eV. 展开更多
关键词 Electron collision Absolute ionization cross section Oxygen molecule
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Absolute blood flow velocity measurement using microsphere tracking in optical coherence tomography 认领 引用
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作者 Huanhuan Yu Mingjie Ni +2 位作者 Dongqing Shang Teng Ma Cuixia Dai 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2025年第6期43-54,共12页
Visualizing blood flow velocity distribution is essential for comprehending the pathogenesis of various diseases and facilitating early diagnosis and treatment.Current hemodynamic studies utilizing optical coherence t... Visualizing blood flow velocity distribution is essential for comprehending the pathogenesis of various diseases and facilitating early diagnosis and treatment.Current hemodynamic studies utilizing optical coherence tomography(OCT)primarily rely on Doppler OCT(D-OCT)and OCT Angiography(OCTA),which measure axial blood vessel velocity or visualize the vascular architecture,respectively.However,these techniques have limitations in accurately quantifying the absolute velocity of red blood cells(RBCs).This study presents a novel method based on microsphere tracking,which enables precise quantification of absolute blood flow velocity along a blood vessel.In phantom experiments,freshly harvested blood mixed with microspheres was infused into a cellulose tube to simulate a single blood vessel.Experimental results,demon-strating an error margin of less than 10%,validated the effectiveness of this method.Blood flow velocities ranging from 0.472 mm/s to 18.9 mm/s were accurately measured.A preliminary in vivo examination of rabbit ear vessels was conducted,further validating the reliability of this method.This study presents a potential method for specific disease diagnosis by detecting tar-geted vessel flow velocity variations using swept-source optical coherence tomography(SS-OCT)combined with microsphere tracking. 展开更多
关键词 Absolute blood flow velocity microsphere tracking swept-source optical coherence tomography
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Absolute parametric instabilities with non-resonant daughter waves in an inhomogeneous plasma 认领 引用
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作者 Kunyu Chen Zhe Gao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2025年第11期153-158,共6页
The existence of absolute parametric instability in an inhomogeneous plasma is revisited in a one-dimensional three-wave model.Non-resonant daughter waves are considered to match the conditions of radio-frequency(RF)-... The existence of absolute parametric instability in an inhomogeneous plasma is revisited in a one-dimensional three-wave model.Non-resonant daughter waves are considered to match the conditions of radio-frequency(RF)-plasma interactions in magnetically confined plasma.Our model shows that such absolute instability has an extremely high threshold and cannot be induced for typical RF-plasma interactions,even if the linear growth rate of the instability achieves the level of ion-cyclotron frequency.As a result,we suggest that it is appropriate to neglect absolute instability when non-resonant daughter waves are involved. 展开更多
关键词 parametric instability absolute instability magnetic confinement fusion
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First acceptance testing of multiple A10 absolute gravimeters in China and analysis of the comparison results 认领 引用 被引量：2
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作者 Xiaotong Zhang Hao Zhou +4 位作者 Ying Jiang Dulin Zhai Gongzhe Wei Hui Li Ziwei Liu 《Geodesy and Geodynamics》 EI CSCD 2023年第4期401-410,共10页
Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the p... Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the purchase and simultaneous testing of 3 A10 absolute gravimeters is unprecedented in China. This study conducted the first acceptance testing of the AGs at 3 locations(the Jiufengshan Gravity Observation Station, the Global Navigation Satellite System Observation Station in Wuhan, and the Jiugongshan Observation Station in Xianning). The results were compared using a method based on expert validation, and the acceptance testing scheme was formulated by referring to the Technical Regulations for Tectonic Environment Monitoring Networks in China and Specifications for Gravimetry Control. Based on the repeatability, precision, and consistency of the measured g values, the results from each instrument were evaluated using the air pressure precision test. Comparing the instrument reference values, the final test results can identify the indicator parameters for 3 A10 AGs, the effects of the surrounding environment, and the related parameters on measurement precision. The precision of A10-059, A10-058, and A10-057 exceeded 0.78 μGal, 0.79 μGal, and 0.42 μGal, respectively.This testing scheme can be used as a reference for conducting acceptance testing of AGs in the future and obtaining absolute gravimetric measurements. 展开更多
关键词 Gravitational acceleration Comparison of absolute gravimeters A10 absolute gravimeters Instrument precision
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Existing conditions of full bandgaps and absolute negative refraction in metallic-dielectric photonic crystal 认领 引用
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作者 董建文 胡新华 汪河洲 《Chinese Physics B》 CAS 2007年第4期1057-1061,共5页
This paper has theoretically studied the characteristic frequencies of band structures in two-dimensional metallic- dielectric photonic crystals. It is demonstrated that a large filling fraction benefits the existence... This paper has theoretically studied the characteristic frequencies of band structures in two-dimensional metallic- dielectric photonic crystals. It is demonstrated that a large filling fraction benefits the existence of absolute photonic band gap, while a smaller filling fraction benefits an absolute negative refraction band. In addition, it also finds that the relation between the cut-off frequency of E-polarized wave and the filling fraction exceeding 10% is content with a linear increasing function, whose coefficients are exponential to the normalized lattice constant. These investigations have significant implications for tuning the operational frequencies to desired applications and manufacturing photonic crystals. 展开更多
关键词 metallic-dielectric photonic crystal absolute photonic band gap absolute negative refraction
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Absolute Instability in Superlattice Miniband Transport 认领 引用
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作者 LEI Xiao-lin 《Chinese Physics Letters》 SCIE EI CAS 1997年第8期605-608,共4页
The possible absolute instability in superlattice miniband transport using the hydrodynamic balance equations for arbitrary energy dispersion is investigated.In contrast to the prediction of the drift-diffusion model ... The possible absolute instability in superlattice miniband transport using the hydrodynamic balance equations for arbitrary energy dispersion is investigated.In contrast to the prediction of the drift-diffusion model that in doped semiconductor superlattices absolute instability occurs closely following the onset of negative differential mobility(NDM),the present analysis shows that a wide-miniband planar superlattice may become absolutely unstable only when it is biased deep in the NDM regime.This result is in agreement with recent experimental findings. 展开更多
关键词 absolute superlattice absolutely
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Review of low timing jitter mode-locked fiber lasers and applications in dual-comb absolute distance measurement 认领 引用 被引量：12
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作者 Haosen Shi Youjian Song +6 位作者 Runmin Li Yuepeng Li Hui Cao Haochen Tian Bowen Liu Lu Chai Minglie Hu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2018年第4期205-217,共13页
Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperatur... Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperature is considerably below one femtosecond at high Fourier frequency. The ultrashort pulse train with ultralow timing jitter enables absolute time-of-flight measurements based on a dual-comb implementation, which is typically composed of a pair of optical frequency combs generated by femtosecond lasers. Dead-zone-free absolute distance measurement with sub-micrometer precision and kHz update rate has been routinely achieved with a dual-comb configuration, which is promising for a number of precision manufacturing applications, from large step-structure measurements prevalent in microelectronic profilometry to three coordinate measurements in large-scale aerospace manufacturing and shipbuilding. In this paper, we first review the sub-femtosecond precision timing jitter characterization methods and approaches for ultralow timing jitter mode-locked fiber laser design. Then, we provide an overview of the state-of-the-art dual-comb absolute ranging technology in terms of working principles, experimental implementations, and measurement precisions. Finally, we discuss the impact of quantum-limited timing jitter on the dual-comb ranging precision at a high update rate. The route to highprecision dual-comb range finder design based on ultralow jitter femtosecond fiber lasers is proposed. 展开更多
关键词 Timing jitter Mode-locked lasers Dual-comb Absolute distance measurement
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Absolute monocyte and lymphocyte count prognostic score for patients with gastric cancer 认领 引用 被引量：10
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作者 Wan Kyu Eo Da Wun Jeong +11 位作者 Hye Jung Chang Kyu Yeoun Won Sung Il Choi Se Hyun Kim Sung Wook Chun Young Lim Oh Tae Hwa Lee Young Ok Kim Ki Hyung Kim Yong Il Ji Ari Kim Heung Yeol Kim 《World Journal of Gastroenterology》 SCIE CAS 2015年第9期2668-2676,共9页
AIM:To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score(AMLPS) in patients with gastric cancer.METHODS:We retrospectively examined the combination of absolute m... AIM:To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score(AMLPS) in patients with gastric cancer.METHODS:We retrospectively examined the combination of absolute monocyte count(AMC) and absolute lymphocyte count(ALC) as prognostic variables in a cohort of 299 gastric cancer patients who underwent surgical resection between 2006 and 2013 and were followed at a single institution.Both AMC and ALC were dichotomized into two groups using cut-off points determined by receiving operator characteristic curve analysis.An AMLPS was generated,which stratified patients into three risk groups:low risk(both low AMC and high ALC),intermediate risk(either high AMC or low ALC),and high risk(both high AMC and low ALC).The primary objective of the study was to validate the impact of AMLPS on both disease-free survival(DFS) and overall survival(OS),and the second objective was to assess the AMLPS as an independent prognostic factor for survival in comparison with known prognostic factors.RESULTS:Using data from the entire cohort,the most discriminative cut-off values of AMC and ALC selected on the receiver operating characteristic curve were 672.4/μL and 1734/μL for DFS and OS.AMLPS risk groups included 158(52.8%) patients in the lowrisk,128(42.8%) in the intermediate-risk,and 13(4.3%) in the high-risk group.With a median followup of 37.2 mo(range:1.7-91.4 mo),five-year DFS rates in the low-,intermediate-,and high-risk groups were 83.4%,78.7%,and 19.8%,respectively.And fiveyear OS rates in the low-,intermediate-,and high-risk groups were 89.3%,81.1%,and 14.4%,respectively.On multivariate analysis performed with patient- and tumor-related factors,we identified AMLPS,age,and pathologic tumor-node-metastasis stage as the most valuable prognostic factors impacting DFS and OS.CONCLUSION:AMLPS identified patients with a poor DFS and OS,and it was independent of age,pathologic stage,and various inflammatory markers. 展开更多
关键词 Monocytes Absolute lymphocyte count Stomach neopla
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