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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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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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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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A High-Order Spatiotemporal Precision-Matching Taylor–Li Scheme for Time-Dependent Problems 被引量:2
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作者 Pengfei WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第12期1461-1471,共11页
Based on the Taylor series method and Li’s spatial differential method, a high-order hybrid Taylor–Li scheme is proposed.The results of a linear advection equation indicate that, using the initial values of the squa... Based on the Taylor series method and Li’s spatial differential method, a high-order hybrid Taylor–Li scheme is proposed.The results of a linear advection equation indicate that, using the initial values of the square-wave type, a result with thirdorder accuracy occurs. However, using initial values associated with the Gaussian function type, a result with very high precision appears. The study demonstrates that, when the order of the time integral is more than three, the corresponding optimal spatial difference order could be higher than six. The results indicate that the reason for why there is no improvement related to an order of spatial difference above six is the use of a time integral scheme that is not high enough. The author also proposes a recursive differential method to improve the Taylor–Li scheme’s computation speed. A more rapid and highprecision program than direct computation of the high-order space differential item is employed, and the computation speed is dramatically boosted. Based on a multiple-precision library, the ultrahigh-order Taylor–Li scheme can be used to solve the advection equation and Burgers’ equation. 展开更多
关键词 Taylor–Li scheme high-order scheme Burgers' equation
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Unveiling the digital renaissance of traditional Chinese medicine:a leap towards holistic healthcare and precision medicine 被引量:1
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作者 Lingyu Linda YE Qinghua PENG Dayue Darrel DUAN 《Digital Chinese Medicine》 2025年第1期1-3,共3页
In the dynamic landscape of modern healthcare and precision medicine,the digital revolution is reshaping medical industries at an unprecedented pace,and traditional Chinese medicine(TCM)is no exception[1-4].The paper... In the dynamic landscape of modern healthcare and precision medicine,the digital revolution is reshaping medical industries at an unprecedented pace,and traditional Chinese medicine(TCM)is no exception[1-4].The paper“From digits towards digitization:the past,present,and future of traditional Chinese medicine”by Academician&TCM National Master Qi WANG(王琦). 展开更多
关键词 digital renaissance traditional chinese medicine tcm precision medicinethe holistic healthcare digital revolution traditional chinese medicine precision medicine medical industries
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Organoid models in oncology:advancing precision cancer therapy and vaccine development 被引量:1
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作者 Yuxuan Xiao Yutao Li +4 位作者 Xilin Jing Lin Weng Xu Liu Qingyun Liu Kezhong Chen 《Cancer Biology & Medicine》 2025年第8期903-927,共25页
Organoids are three-dimensional stem cell-derived models that offer a more physiologically relevant representation of tumor biology compared to traditional two-dimensional cell cultures or animal models.Organoids pres... Organoids are three-dimensional stem cell-derived models that offer a more physiologically relevant representation of tumor biology compared to traditional two-dimensional cell cultures or animal models.Organoids preserve the complex tissue architecture and cellular diversity of human cancers,enabling more accurate predictions of tumor growth,metastasis,and drug responses.Integration with microfluidic platforms,such as organ-on-a-chip systems,further enhances the ability to model tumor-environment interactions in real-time.Organoids facilitate in-depth exploration of tumor heterogeneity,molecular mechanisms,and the development of personalized treatment strategies when coupled with multi-omics technologies.Organoids provide a platform for investigating tumor-immune cell interactions,which aid in the design and testing of immune-based therapies and vaccines.Taken together,these features position organoids as a transformative tool in advancing cancer research and precision medicine. 展开更多
关键词 ORGANOIDS ONCOLOGY precision therapy VACCINE
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Revolutionizing gastroenterology and hepatology with artificial intelligence:From precision diagnosis to equitable healthcare through interdisciplinary practice 被引量:1
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作者 Zhi-Li Chen Chao Wang Fang Wang 《World Journal of Gastroenterology》 2025年第24期25-49,共25页
Artificial intelligence(AI)is driving a paradigm shift in gastroenterology and hepa-tology by delivering cutting-edge tools for disease screening,diagnosis,treatment,and prognostic management.Through deep learning,rad... Artificial intelligence(AI)is driving a paradigm shift in gastroenterology and hepa-tology by delivering cutting-edge tools for disease screening,diagnosis,treatment,and prognostic management.Through deep learning,radiomics,and multimodal data integration,AI has achieved diagnostic parity with expert cli-nicians in endoscopic image analysis(e.g.,early gastric cancer detection,colorectal polyp identification)and non-invasive assessment of liver pathologies(e.g.,fibrosis staging,fatty liver typing)while demonstrating utility in personalized care scenarios such as predicting hepatocellular carcinoma recurrence and opti-mizing inflammatory bowel disease treatment responses.Despite these advance-ments challenges persist including limited model generalization due to frag-mented datasets,algorithmic limitations in rare conditions(e.g.,pediatric liver diseases)caused by insufficient training data,and unresolved ethical issues related to bias,accountability,and patient privacy.Mitigation strategies involve constructing standardized multicenter databases,validating AI tools through prospective trials,leveraging federated learning to address data scarcity,and de-veloping interpretable systems(e.g.,attention heatmap visualization)to enhance clinical trust.Integrating generative AI,digital twin technologies,and establishing unified ethical/regulatory frameworks will accelerate AI adoption in primary care and foster equitable healthcare access while interdisciplinary collaboration and evidence-based implementation remain critical for realizing AI’s potential to redefine precision care for digestive disorders,improve global health outcomes,and reshape healthcare equity. 展开更多
关键词 Artificial intelligence precision medicine GASTROENTEROLOGY HEPATOLOGY Multimodal data integration Deep learning MICROBIOME
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Artificial intelligence and machine learning in spine care:Advancing precision diagnosis,treatment,and rehabilitation 被引量:1
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作者 Aqil M Jawed Lei Zhang +3 位作者 Zhang Zhang Qi Liu Waqas Ahmed Huan Wang 《World Journal of Orthopedics》 2025年第8期14-31,共18页
Artificial intelligence(AI)and machine learning(ML)are transforming spine care by addressing diagnostics,treatment planning,and rehabilitation challenges.This study highlights advancements in precision medicine for sp... Artificial intelligence(AI)and machine learning(ML)are transforming spine care by addressing diagnostics,treatment planning,and rehabilitation challenges.This study highlights advancements in precision medicine for spinal pathologies,leveraging AI and ML to enhance diagnostic accuracy through deep learning algorithms,enabling faster and more accurate detection of abnormalities.AIpowered robotics and surgical navigation systems improve implant placement precision and reduce complications in complex spine surgeries.Wearable devices and virtual platforms,designed with AI,offer personalized,adaptive therapies that improve treatment adherence and recovery outcomes.AI also enables preventive interventions by assessing spine condition risks early.Despite progress,challenges remain,including limited healthcare datasets,algorithmic biases,ethical concerns,and integration into existing systems.Interdisciplinary collaboration and explainable AI frameworks are essential to unlock AI’s full potential in spine care.Future developments include multimodal AI systems integrating imaging,clinical,and genetic data for holistic treatment approaches.AI and ML promise significant improvements in diagnostic accuracy,treatment personalization,service accessibility,and cost efficiency,paving the way for more streamlined and effective spine care,ultimately enhancing patient outcomes. 展开更多
关键词 Spine care Spine artificial intelligence Machine learning diagnostics precision rehabilitation Robotics surgery
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Real-time retrieval of high-precision ZTD maps using GNSS observation 被引量:1
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作者 Qingzhi Zhao Wei Wang +11 位作者 Jinfang Yin Kan Wu Lv Zhou Yibin Yao Pengcheng Wang Jing Su Xiaocheng Wang Han Wang Jia Bao Yumeng Hu Zhou Zhuo Yuting Gao 《Geodesy and Geodynamics》 2025年第5期524-535,共12页
Zenith Tropospheric Delay(ZTD)is an important factor that restricts the high-precision positioning of global navigation satellite system(GNSS),and it is of great significance in establishing a real-time and highprecis... Zenith Tropospheric Delay(ZTD)is an important factor that restricts the high-precision positioning of global navigation satellite system(GNSS),and it is of great significance in establishing a real-time and highprecision ZTD model.However,existing ZTD models only consider the impact of linear terms on ZTD estimation,whereas the nonlinear factors have rarely been investigated before and thus become the focus of this study.A real-time and high-precision ZTD model for large height difference area is proposed by considering the linear and nonlinear characteristics of ZTD spatiotemporal variations and is called the realtime linear and nonlinearity ZTD(RLNZ)model.This model uses the ZTD estimated from the Global Pressure and Temperature 3(GPT3)model as the initial value.The linear impacts of periodic term and height on the estimation of ZTD difference between GNSS and GPT3 model are first considered.In addition,nonlinear factors such as geographical location and time are further used to fit the remaining nonlinear ZTD residuals using the general regression neural network method.Finally,the RLNZ-derived ZTD is obtained at an arbitrary location.The western United States,with height difference ranging from-500 to 4000 m,is selected,and the hourly ZTD of 484 GNSS stations provided by the Nevada Geodetic Laboratory(NGL)and the data of 9 radiosonde(RS)stations in the year 2021 are used.Experiment results show that a better performance of ZTD estimation can be retrieved from the proposed RLNZ model when compared with the GPT3 model.Statistical results show the averaged root mean square(RMS),Bias,and mean absolute error(MAE)of ZTD from GPT3 and RLNZ models are 33.7/0.8/25.7 mm and 22.6/0.1/17.4 mm,respectively.The average improvement rate of the RLNZ model is 33% when compared to the GPT3 model.Finally,the application of the proposed RLNZ model in simulated real-time Precise Point Positioning(PPP)indicates that the accuracy of PPP in N,E and U components is improved by 8%,2%,and 6% when compared with that from the GPT3-based PPP.Meanwhile,the convergence time in N and U components is improved by 23% and 7%,respectively.Such results verify the superiority of the proposed RLNZ model in retrieving realtime ZTD maps for GNSS positioning and navigation applications. 展开更多
关键词 Zenith tropospheric delay Global navigation satellite system RLNZ model precise point positioning
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Multi-objective optimization of grinding process parameters for improving gear machining precision 被引量:1
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作者 YOU Tong-fei HAN Jiang +4 位作者 TIAN Xiao-qing TANG Jian-ping LU Yi-guo LI Guang-hui XIA Lian 《Journal of Central South University》 2025年第2期538-551,共14页
The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can caus... The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can cause changes in cutting force/heat,resulting in affecting gear machining precision.Therefore,this paper studies the effect of different process parameters on gear machining precision.A multi-objective optimization model is established for the relationship between process parameters and tooth surface deviations,tooth profile deviations,and tooth lead deviations through the cutting speed,feed rate,and cutting depth of the worm wheel gear grinding machine.The response surface method(RSM)is used for experimental design,and the corresponding experimental results and optimal process parameters are obtained.Subsequently,gray relational analysis-principal component analysis(GRA-PCA),particle swarm optimization(PSO),and genetic algorithm-particle swarm optimization(GA-PSO)methods are used to analyze the experimental results and obtain different optimal process parameters.The results show that optimal process parameters obtained by the GRA-PCA,PSO,and GA-PSO methods improve the gear machining precision.Moreover,the gear machining precision obtained by GA-PSO is superior to other methods. 展开更多
关键词 worm wheel gear grinding machine gear machining precision machining process parameters multi objective optimization
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The treatment of breast cancer in the era of precision medicine
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作者 Jingwen Bai Yiyang Gao Guojun Zhang 《Cancer Biology & Medicine》 2025年第4期322-347,共26页
The management of breast cancer,one of the most common and heterogeneous malignancies,has transformed with the advent of precision medicine.This review explores current developments in genetic profiling,molecular diag... The management of breast cancer,one of the most common and heterogeneous malignancies,has transformed with the advent of precision medicine.This review explores current developments in genetic profiling,molecular diagnostics,and targeted therapies that have revolutionized breast cancer treatment.Key innovations,such as cyclin-dependent kinases 4/6(CDK4/6)inhibitors,antibodydrug conjugates(ADCs),and immune checkpoint inhibitors(ICIs),have improved outcomes for hormone receptor-positive(HR+),HER2-positive(HER2+),and triple-negative breast cancer(TNBC)subtypes remarkably.Additionally,emerging treatments,such as PI3K inhibitors,poly(ADP-ribose)polymerase(PARP)inhibitors,and m RNA-based therapies,offer new avenues for targeting specific genetic mutations and improving treatment response,particularly in difficult-to-treat breast cancer subtypes.The integration of liquid biopsy technologies provides a non-invasive approach for real-time monitoring of tumor evolution and treatment response,thus enabling dynamic adjustments to therapy.Molecular imaging and artificial intelligence(AI)are increasingly crucial in enhancing diagnostic precision,personalizing treatment plans,and predicting therapeutic outcomes.As precision medicine continues to evolve,it has the potential to significantly improve survival rates,decrease recurrence,and enhance quality of life for patients with breast cancer.By combining cutting-edge diagnostics,personalized therapies,and emerging treatments,precision medicine can transform breast cancer care by offering more effective,individualized,and less invasive treatment options. 展开更多
关键词 Breast cancer precision medicine diagnostic precision personalized therapy
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Advanced Techniques for Precision Assessment in UAV LiDAR Systems
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作者 Hany Abdel-MAKSOUD Tarek Abdel AZIZ +1 位作者 Ahmed S.ELSHARKAWY OsamaMOURSY 《Journal of Geodesy and Geoinformation Science》 2025年第2期90-107,共18页
The increasing use of UAV-based LiDAR systems for high-resolution mapping highlights the need for reliable,field-validated accuracy assessment methods.This study presents a practical technique for evaluating geometric... The increasing use of UAV-based LiDAR systems for high-resolution mapping highlights the need for reliable,field-validated accuracy assessment methods.This study presents a practical technique for evaluating geometric and radiometric performance using georeferenced,high-reflectivity foil targets.The method enables precise extraction of target centers and correction of systematic georeferencing errors through 3D transformation.The approach was applied at the Tora Cement Factory in Cairo,Egypt—an industrial site with complex topography—using a DJI Matrice 300 RTK UAV equipped with the Zenmuse L1 LiDAR sensor and Zenmuse P1 photogrammetric camera.Three test flights were performed at altitudes of 50 m(nadir and oblique)and 70 m(oblique),with a high-resolution Structure-from-Motion(SfM)point cloud generated for reference.After transformation,the global RMSE of the LiDAR dataset was reduced to approximately 2.8∼3.2 cm,improving upon the raw uncorrected accuracy of up to 4.6 cm.Surface-wise comparisons showed RMSEs of 3.1 cm on flat areas,3.8 cm on rugged terrain,and 4.5 cm on vertical structures.Additionally,the RGB data embedded in the LiDAR point cloud exhibited a systematic spatial offset between 18 and 43 cm,with an average internal standard deviation near 5 cm,indicating a potential limitation for radiometric applications.The proposed method offers a cost-effective,accurate,and repeatable solution for UAV LiDAR validation and supports operational deployment,quality assurance,and system calibration in real-world scenarios. 展开更多
关键词 UAV LIDAR precision ACCURACY
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Axillary surgery de-escalation for breast cancer in the era of precision medicine
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作者 Xueying Du Xiao Sun +3 位作者 Yanbing Liu Zhaopeng Zhang Yongsheng Wang Zhao Bi 《Cancer Biology & Medicine》 2025年第8期871-873,共3页
In the era of precision medicine,the breast cancer surgical treatment field is gradually moving toward a de-escalation model.Through precise preoperative assessments and multidisciplinary decision-making,surgical trau... In the era of precision medicine,the breast cancer surgical treatment field is gradually moving toward a de-escalation model.Through precise preoperative assessments and multidisciplinary decision-making,surgical trauma can be decreased,and patients’quality of life can be improved by ensuring safety.Herein,we explore the axillary de-escalation surgery model for breast cancer. 展开更多
关键词 surgical trauma quality life precision medicinethe breast cancer surgery breast cancer precision medicine axillary de escalation
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Special Column on Precision Psychiatry in Mood Disorders
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《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第1期I0001-I0001,共1页
Precision Psychiatry in Mood Disorders refers to the application of precision medicine principles in the field of mood disorders,such as depression and bipolar disorder.It involves the use of advanced technologies,bio... Precision Psychiatry in Mood Disorders refers to the application of precision medicine principles in the field of mood disorders,such as depression and bipolar disorder.It involves the use of advanced technologies,biomarkers,and personalized treatment approaches to improve the accuracy of diagnosis,prognosis,and treatment selection for individuals with mood disorders. 展开更多
关键词 DIAGNOSIS TREATMENT precision
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Frequency shifts of high-order harmonics from ZnO crystals by chirped laser pulses
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作者 Yu Zhao Xiao-Jin Liu +3 位作者 Shuang Wang Xiao-Xin Huo Yun-He Xing Jun Zhang 《Chinese Physics B》 2025年第3期340-346,共7页
We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp a... We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp and blueshifts for those with positive chirp,which is due to the change in the instantaneous frequency of the driving laser for different chirped pulses.The analysis of crystal-momentum-resolved(k-resolved)HHG reveals that the frequency shifts are equal for the harmonics generated by different crystal momentum channels.The frequency shifts in the cutoff region are larger than those in the plateau region.With the increase of the absolute value of the chirp parameters,the frequency shifts of HHG become more significant,leading to the shifts from odd-to even-order harmonics.We also demonstrate that the frequency shifts of harmonic spectra are related to the duration of the chirped laser field,but are insensitive to the laser intensity and dephasing time. 展开更多
关键词 high-order harmonic generation ZnO crystal chirped laser pulse spectral shift
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Accessing polyarene-fused ten-membered lactams via oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation
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作者 Chen-Chang Cui Shao-Qing Shi +4 位作者 Lu-Yao Wang Feng Lin Man-Su Tu Wen-Juan Hao Bo Jiang 《Chinese Chemical Letters》 2025年第6期479-483,共5页
A new oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation reaction ofγ-indolyl phenols as 1,7-dinucleophiles andα,β-alkynals with the aid of Sc(OTf)_(3)is reported,enabling the highly regiosel... A new oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation reaction ofγ-indolyl phenols as 1,7-dinucleophiles andα,β-alkynals with the aid of Sc(OTf)_(3)is reported,enabling the highly regioselective access to unprecedented polyarene-fused ten-membered lactams bearing a bridged aryl-aryl-indole scaffold in moderate to good yields.This protocol demonstrates a broad substrate scope,good compatibility with substituents and complete regioselectivity,providing an organocatalytic modular synthetic strategy for creating medium-sized lactams. 展开更多
关键词 NHC-catalysis high-order annulation Regioselectivity Medium-sized lactams γ-Indolyl phenols
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Unveiling the role of high-order anharmonicity in thermal expansion: A first-principles perspective
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作者 Tianxu Zhang Kun Zhou +5 位作者 Yingjian Li Chenhao Yi Muhammad Faizan Yuhao Fu Xinjiang Wang Lijun Zhang 《Chinese Physics B》 2025年第4期212-219,共8页
Thermal expansion is crucial for various industrial processes and is increasingly the focus of research endeavors aimed at improving material performance.However,it is the continuous advancements in first-principles c... Thermal expansion is crucial for various industrial processes and is increasingly the focus of research endeavors aimed at improving material performance.However,it is the continuous advancements in first-principles calculations that have enabled researchers to understand the microscopic origins of thermal expansion.In this study,we propose a coefficient of thermal expansion(CTE)calculation scheme based on self-consistent phonon theory,incorporating the fourth-order anharmonicity.We selected four structures(Si,CaZrF_(6),SrTiO_(3),NaBr)to investigate high-order anharmonicity’s impact on their CTEs,based on bonding types.The results indicate that our method goes beyond the second-order quasi-harmonic approximation and the third-order perturbation theory,aligning closely with experimental data.Furthermore,we observed that an increase in the ionicity of the structures leads to a more pronounced influence of high-order anharmonicity on CTE,with this effect primarily manifesting in variations of the Grüneisen parameter.Our research provides a theoretical foundation for accurately predicting and regulating the thermal expansion behavior of materials. 展开更多
关键词 high-order anharmonicity Grüneisen parameter thermal expansion first-principles calculations
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A High-Order Scalar Auxiliary Variable Approach for Nonlinear Parabolic Integro-Differential Equations
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作者 YAN Li-na ZHANG Gen-gen HUANG Qiong-ao 《Chinese Quarterly Journal of Mathematics》 2025年第3期262-270,共9页
An efficient and accurate scalar auxiliary variable(SAV)scheme for numerically solving nonlinear parabolic integro-differential equation(PIDE)is developed in this paper.The original equation is first transformed into ... An efficient and accurate scalar auxiliary variable(SAV)scheme for numerically solving nonlinear parabolic integro-differential equation(PIDE)is developed in this paper.The original equation is first transformed into an equivalent system,and the k-order backward differentiation formula(BDF k)and central difference formula are used to discretize the temporal and spatial derivatives,respectively.Different from the traditional discrete method that adopts full implicit or full explicit for the nonlinear integral terms,the proposed scheme is based on the SAV idea and can be treated semi-implicitly,taking into account both accuracy and effectiveness.Numerical results are presented to demonstrate the high-order convergence(up to fourth-order)of the developed schemes and it is computationally efficient in long-time computations. 展开更多
关键词 Parabolic integro-differential equation Scalar auxiliary variable Fredholm equation high-order BDF scheme
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Influence of excited states in high-order harmonic generation at intense mid-infrared field
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作者 Yan Fang Da-Wei Tian +2 位作者 Yue Cao Xiao-Lei Hao Zheng Shu 《Chinese Physics B》 2025年第10期142-147,共6页
We present a comprehensive study on the role of various excited states in high-order harmonic generation of hydrogen atoms driven by a long-wavelength(1500 nm)laser field.By numerically solving the time-dependent Schr... We present a comprehensive study on the role of various excited states in high-order harmonic generation of hydrogen atoms driven by a long-wavelength(1500 nm)laser field.By numerically solving the time-dependent Schrodinger equation(TDSE)and performing a time-frequency analysis,we investigate the influence of individual excited states on the harmonic spectrum.Our results reveal that the 2s excited state primarily contributes to the enhancement of high-energy harmonic yields by facilitating long electron trajectories,while the 2p excited state predominantly suppresses harmonic yields in the lower-energy region(20th-50th orders)by altering the contributions of electron trajectories.Our results highlight the critical role of the excited states in the HHG process,even at longer laser wavelengths. 展开更多
关键词 high-order harmonic generation(HHG) strong-field physics excited-state effect
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Analysis and optimization of microchannel array precision grinding processes with micro-structured micro-grinding tool
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作者 Jianfei JIA Qinghe ZHANG +7 位作者 Wei YANG Honghui YAO Guicheng WU Huan ZHAO Jianhui ZHU Kenan LI Bing GUO Jun QIN 《Chinese Journal of Aeronautics》 2025年第7期669-683,共15页
Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro... Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro-structure has been applied on the micro-grinding tool.A morphology modeling has been established in this study to characterize the surface of microstructured micro-grinding tool,and the grinding performance of micro-structured micro-grinding tool has been analyzed through undeformed chip thickness,abrasive edge width,and effective distance between abrasives.Then deviation analysis,path optimization and parameter optimization of microchannel array precision grinding have been finished to improve processing quality and efficiency,and the deflection angle has the most obvious effects on the rectangular slot depth,micro-structured micro-grinding tool could reduce 10%surface roughness and 20%grinding force compared to original micro-grinding tool.Finally,the microchannel array has been machined with a size deviation of 2μm and surface roughness of 0.2μm. 展开更多
关键词 GRINDING precision grinding Microchannel array MICRO-STRUCTURE Micro-grinding tool
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